JP6708822B2 - Developer remaining amount detecting device, developing device, image forming apparatus, process cartridge, and developer remaining amount detecting method - Google Patents

Description

The present invention relates to a developer remaining amount detecting device, a developing device, an image forming apparatus , a process cartridge, and a developer remaining amount detecting method.

In recent years, computerization of information has tended to be promoted, and image processing apparatuses such as printers and facsimiles used to output computerized information and scanners used to computerize documents have become indispensable devices. Among such image processing apparatuses, as an image forming and outputting method, an electrophotographic method for performing image forming and outputting by developing an electrostatic latent image formed on a photoconductor and transferring the formed image to a sheet. It has been known.

In an electrophotographic image forming apparatus, a developer is supplied from a container serving as a developer supply source to a developing device that develops an electrostatic latent image formed on a photoconductor. As a method for detecting the remaining amount of the developer supplied as described above, for example, a member for stirring the developer is used to deform the pressure-sensitive sheet, and the member to be detected accompanying the deformation of the pressure-sensitive sheet. Has been proposed (for example, see Patent Document 1).

In the case of the method disclosed in Patent Document 1, the amount of toner in the container is not always reflected uniformly on the deformation of the pressed sheet. In addition, there is a problem in detection accuracy such as a change with time of the pressure-sensitive sheet and adhesion of the developer to the pressure-sensitive sheet.

The present invention has been made in consideration of the above circumstances, and an object thereof is to detect with high accuracy a state in which the remaining amount of the color developer in the developing device is low.

In order to solve the above problems, one embodiment of the present invention is housed in a housing portion included in a developing device which develops an electrostatic latent image formed on an image carrier , and rotates inside the housing portion. A developer remaining amount detecting device that is fixed to a shaft and detects the remaining amount of the developer that is agitated by a stirring unit that rotates inside the accommodating unit . an oscillator for outputting a signal of a frequency, are disposed in the accommodating portion, the opposed to the oscillating unit via the housing of the receiving portion, it is released from the state of being displaced by rotation of the stirring portion The vibration part formed of a material that affects the magnetic flux and vibrates in the direction opposite to the oscillation part, and frequency-related information about the frequency of the oscillation signal of the oscillation part is acquired at a predetermined cycle, and the vibration of the vibration part is obtained. A detection processing unit that detects a vibration state of the vibration unit based on a change in the frequency-related information that changes in accordance with the detection processing unit that detects the remaining amount of the color developer inside the storage unit based on the vibration state . A developer remaining amount detecting device comprising:

According to the present invention, it is possible to detect with high accuracy a state where the remaining amount of the color developer in the developing device is low.

FIG. 3 is a diagram showing a mechanical configuration of an image forming apparatus including a developing device in which a magnetic flux sensor according to an embodiment of the present invention is mounted. FIG. 3 is a side sectional view showing the configuration of the process cartridge according to the embodiment of the present invention. It is a figure which shows the attachment aspect of the magnetic flux sensor to the process cartridge which concerns on embodiment of this invention. It is a figure which shows the attachment aspect of the magnetic flux sensor to the process cartridge which concerns on embodiment of this invention. It is a figure which shows the circuit structure of the magnetic flux sensor which concerns on embodiment of this invention. It is a figure which shows the counting aspect of the output signal of the magnetic flux sensor which concerns on embodiment of this invention. It is a perspective view showing the appearance of the magnetic flux sensor concerning the embodiment of the present invention. It is a block diagram which shows the structure of the controller which acquires the signal of the magnetic flux sensor which concerns on embodiment of this invention. It is a figure which shows the arrangement|positioning relationship of the magnetic flux sensor and diaphragm which concern on embodiment of this invention. It is a figure which shows the effect|action when a magnetic flux passes through the diaphragm which concerns on embodiment of this invention. It is a figure which shows the oscillation frequency of the magnetic flux sensor according to the distance of the diaphragm and magnetic flux sensor which concern on embodiment of this invention. It is a perspective view which shows the diaphragm which concerns on embodiment of this invention. It is a side view which shows the arrangement|positioning relationship of the diaphragm and the stirring member which concern on embodiment of this invention. It is a side view which shows the arrangement|positioning relationship of the diaphragm and the stirring member which concern on embodiment of this invention. It is a top view which shows the arrangement|positioning relationship of the diaphragm and the stirring member which concern on embodiment of this invention. It is a side view which shows the arrangement|positioning relationship of the diaphragm and the stirring member which concern on embodiment of this invention. It is a top view which shows the vibration state of the diaphragm which concerns on embodiment of this invention. It is a side view which shows the relationship between the vibration state of the diaphragm which concerns on embodiment of this invention, and a color developer. It is a figure which shows the time-dependent change of the count value according to the oscillation frequency of the magnetic flux sensor which changes according to the damping of the vibration of the diaphragm which concerns on embodiment of this invention. 6 is a flowchart showing a toner remaining amount detecting operation according to the embodiment of the present invention. It is a figure which shows the analysis aspect of the count value which concerns on embodiment of this invention. It is a figure which shows the sampling period of a count value and the relationship of the vibration period of a diaphragm which concern on embodiment of this invention. It is a figure which shows the space|interval of the magnetic flux sensor and diaphragm which concern on embodiment of this invention. It is a figure which shows the example of the arrangement|positioning height of the magnetic flux sensor and diaphragm which concern on embodiment of this invention. It is a figure which shows the example of the arrangement|positioning height of the magnetic flux sensor and diaphragm which concern on embodiment of this invention. It is a side view which shows the other example of the coil which concerns on embodiment of this invention. It is a front view which shows the other example of the coil which concerns on embodiment of this invention. FIG. 6 is a side sectional view showing another example of the process cartridge according to the embodiment of the present invention. FIG. 6 is a side sectional view showing a configuration of a process cartridge and its periphery according to another embodiment of the present invention. FIG. 6 is a side sectional view showing a configuration of a process cartridge and its periphery according to another embodiment of the present invention. FIG. 6 is a side sectional view showing a configuration of a process cartridge and its periphery according to another embodiment of the present invention. FIG. 6 is a side sectional view showing a configuration of a process cartridge and its periphery according to another embodiment of the present invention. It is a figure which shows the positioning aspect of the process cartridge which concerns on embodiment of this invention. It is a figure which shows the positioning aspect of the process cartridge which concerns on embodiment of this invention.

Embodiment 1.
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, detection of the remaining amount of toner in a developing device that develops an electrostatic latent image formed on a photoconductor in an electrophotographic image forming apparatus will be described as an example.

FIG. 1 is a side view showing an image forming output mechanism included in the image forming apparatus 100 according to the present embodiment. As shown in FIG. 1, the image forming apparatus 100 according to the present embodiment has a configuration in which image forming units 106K to 106Y of respective colors are arranged along a conveyor belt 105 that is an endless moving unit. It is called a tandem type. That is, along the transport belt 105, which is an intermediate transfer belt on which an intermediate transfer image is formed for transfer onto a sheet (an example of a recording medium) 104 that is separated and fed by the sheet feed roller 102 from the sheet feed tray 101, A plurality of image forming units (electrophotographic process units) 106Y, 106M, 106C, and 106K (hereinafter collectively referred to as the image forming unit 106) are arranged in order from the upstream side of the conveying belt 105 in the conveying direction.

Further, the paper 104 fed from the paper feed tray 101 is once stopped by the registration rollers 103, and is sent to the image transfer position from the conveyor belt 105 according to the image forming timing in the image forming unit 106.

The plurality of image forming units 106Y, 106M, 106C, and 106K have the same internal configuration except that the colors of toner images to be formed are different. The image forming unit 106K forms a black image, the image forming unit 106M forms a magenta image, the image forming unit 106C forms a cyan image, and the image forming unit 106Y forms a yellow image. In the following description, the image forming unit 106Y will be specifically described, but the other image forming units 106M, 106C, and 106K are the same as the image forming unit 106Y, and thus the image forming units 106M, 106C, and 106K. With respect to each of the constituent elements, the reference numerals distinguished by M, C, and K are displayed in the drawing instead of Y attached to each constituent element of the image forming unit 106Y, and the description thereof will be omitted.

The conveyor belt 105 is an endless belt spanned by a driving roller 107 and a driven roller 108 which are rotationally driven, that is, an endless belt. The drive roller 107 is rotationally driven by a drive motor (not shown), and the drive motor, the drive roller 107, and the driven roller 108 function as drive means for moving the conveyor belt 105, which is an endless moving means. ..

At the time of image formation, the first image forming unit 106Y transfers the yellow toner image to the rotationally driven conveyance belt 105. The image forming unit 106Y includes a photoconductor drum 109Y as a photoconductor, a charging device 110Y arranged around the photoconductor drum 109Y, an optical writing device 111, a developing device 112Y, a photoconductor cleaner 113Y, and a charge eliminator (not shown). ) Etc. The optical writing device 111 is configured to irradiate each of the photosensitive drums 109Y, 109M, 109C, and 109K (hereinafter, referred to as "photosensitive drum 109" as a whole) with light.

At the time of image formation, the outer peripheral surface of the photoconductor drum 109Y is uniformly charged by the charger 110Y in the dark, and then writing is performed by the light from the light source corresponding to the yellow image from the optical writing device 111, and the static electricity is generated. A latent image is formed. The developing device 112Y visualizes this electrostatic latent image with yellow toner, and as a result, a yellow toner image is formed on the photosensitive drum 109Y.

This toner image is transferred onto the conveyor belt 105 by the function of the transfer device 115Y at a position (transfer position) where the photosensitive drum 109Y and the conveyor belt 105 are in contact with or closest to each other. By this transfer, an image of yellow toner is formed on the conveyor belt 105. After the transfer of the toner image is completed, the photoconductor drum 113Y wipes off the unnecessary toner remaining on the outer peripheral surface by the photoconductor cleaner 113Y, and then the charge is removed by the charge eliminator and stands by for the next image formation.

As described above, the yellow toner image transferred onto the conveyance belt 105 by the image forming unit 106Y is conveyed to the next image forming unit 106M by the roller driving of the conveyance belt 105. In the image forming unit 106M, a magenta toner image is formed on the photosensitive drum 109M by a process similar to the image forming process in the image forming unit 106Y, and the toner image is transferred by being superimposed on the already formed yellow image. To be done.

The yellow and magenta toner images transferred onto the conveyor belt 105 are further conveyed to the next image forming units 106C and 106K, and by the same operation, the cyan toner image formed on the photosensitive drum 109C and The black toner image formed on the body drum 109K is superimposed and transferred onto the already transferred image. In this way, a full-color intermediate transfer image is formed on the conveyor belt 105.

The papers 104 stored in the paper feed tray 101 are fed out in order from the topmost one, and the intermediate transfer image formed on the conveyor belt 105 is formed at a position where the conveyance path comes into contact with the conveyor belt 105 or comes closest to the conveyor belt 105. It is transferred on the paper. As a result, an image is formed on the surface of the sheet 104. The sheet 104 on which an image is formed is further conveyed, the image is fixed by the fixing device 116, and then the sheet is discharged to the outside of the image forming apparatus.

Further, a belt cleaner 118 is provided for the conveyor belt 105. As shown in FIG. 1, the belt cleaner 118 is a cleaning blade that is pressed against the conveyor belt 105 on the downstream side of the transfer position of the image from the conveyor belt 105 to the sheet 104 and on the upstream side of the photosensitive drum 109. And is a developer removing portion that scrapes off the toner adhering to the surface of the transport belt 105.

The image forming unit 106 shown in FIG. 1 is configured as a process cartridge packaged as one unit. The configuration of the process cartridge according to this embodiment will be described with reference to FIG. The toner supply configurations are generally common to the CMYK colors, and the configuration of one image forming unit 106 is shown in FIG.

As shown in FIG. 2, in the process cartridge that is the image forming unit 106, as described in FIG. 1, the charger 110, the developing unit 112, and the photoconductor cleaner 113 are arranged around the photoconductor drum 109. .. These configurations function as a developing mechanism. The charger 110 is configured as a roller and rotates according to the movement of the surface due to the rotation of the photosensitive drum 109. The photosensitive drum 109 is configured to rotate clockwise in the drawing.

As shown in FIG. 2, the developing device 112 includes a developing roller 112a, a developing blade 112b, a supply roller 112c, and a toner containing section 200. The developing roller 112a is a roller that conveys a developer to the surface of the photoconductor drum 109 to develop the electrostatic latent image formed on the photoconductor drum 109. The developing roller 112a is configured to rotate counterclockwise in the figure.

In the developing device 112, the toner, which is supplied onto the surface of the developing roller 112a by the developing blade 112b and has a predetermined thickness, is conveyed to the photosensitive drum 109 side by the rotation of the developing roller 112a. As a result, toner is transferred from the surface of the developing roller 112a to the surface of the photosensitive drum 109 according to the electrostatic latent image formed on the surface of the photosensitive drum 109.

Toner supplied from the toner storage unit 200, which is a storage unit for the developer, is supplied to the developing roller 112a by the supply roller 112c. When the toner inside the toner container 200 is used up, the toner is no longer supplied from the supply roller 112c to the developing roller 112a. It is the gist of the present embodiment to detect the state where the toner amount inside the toner storage unit 200 is low.

The magnetic flux sensor 10 is attached to the outer wall of the housing forming the toner storage unit 200. A diaphragm 201 is attached to the inner wall of the housing. The inner wall provided with the diaphragm 201 is the back side of the outer wall to which the magnetic flux sensor 10 (permeability sensor) is attached in FIG. Therefore, the diaphragm 201 is arranged so as to face the magnetic flux sensor 10.

FIGS. 3A to 3D are views showing how the magnetic flux sensor 10 and the diaphragm 201 in the toner storage unit 200 are attached. The vibration plate 201 is a rectangular plate-shaped component, and is arranged in a cantilever state in which one end in the longitudinal direction is fixed to the housing of the toner storage unit 200. In addition, a weight 202 is arranged at the end of the diaphragm 201 that is not fixed in the longitudinal direction. The weight 202 has a function of adjusting the frequency of vibration of the diaphragm 201 and a function of vibrating the diaphragm 201.

As shown in FIG. 2, a rotating shaft 204 and a stirring member 205 are provided inside the toner storage unit 200 as a structure for stirring the toner inside. The rotation shaft 204 is a shaft that rotates inside the toner storage unit 200. An agitating member 205 is fixed to the rotating shaft 204, and the agitating member 205 rotates as the rotating shaft 204 rotates, so that the toner inside the toner container 200 is agitated. Further, the longitudinal direction of the diaphragm 201 is arranged substantially parallel to the axial direction of the rotary shaft 204.

In addition to stirring the toner, the stirring member 205 has a function of repelling the weight 202 provided on the vibration plate 201 by rotation. As a result, the weight 202 is repelled and the diaphragm 201 vibrates every time the stirring member 205 rotates once. That is, the vibrating plate 201 functions as a vibrating section, and the stirring member 205 functions as a vibration applying section. It is the gist of the present embodiment to detect the remaining amount of toner inside the toner container 200 by detecting the vibration of the diaphragm 201.

FIG. 3A is a perspective view showing the inner wall of the toner storage unit 200 before the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 3B is a perspective view showing the toner storage unit 200 to which the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 3C is a top view showing the toner storage unit 200 to which the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 3D is a cross-sectional view taken along the section line AA of FIG.

When attaching the diaphragm 201 and the magnetic flux sensor 10 as shown in FIGS. 3A to 3D, attachment is performed by adhesion via an adhesive layer. As a result, there is no need to provide a through hole in the wall surface of the housing as in the case of mounting using a fastening member such as a screw. Therefore, it is possible to prevent the toner inside from leaking out from the through hole and scattering to the outer wall of the toner containing unit 200. In other words, the space in which the diaphragm 201 is arranged and the space in which the magnetic flux sensor 10 is arranged are cut off in the direction in which they face each other. Therefore, leakage of toner can be prevented.

Further, according to the mounting modes shown in FIGS. 3A to 3D, since a fastening member such as a screw is not required, the cost is reduced by reducing the number of parts, and the assembling work is facilitated by reducing the fastening work. The productivity can be improved by Further, when the through hole is provided, a seal member or the like for preventing the above-mentioned toner scattering is also required, but this is not necessary in the mounting mode according to the present embodiment, so that further cost reduction and assembly work are possible. Can be facilitated.

Note that FIGS. 3A to 3D are shown on the assumption that the weight 202 and the pedestal are assembled and integrated with the diaphragm 201. With such an integrated structure, the toner container 200 may be assembled as shown in FIG. 3A, or the pedestal, the diaphragm 201, and the weight 202 may be assembled in this order. Further, when attaching the pedestal and the weight 202 to the vibration plate 201, various methods such as welding, welding, caulking, and adhesion can be used.

FIG. 4A to FIG. 4D are diagrams showing other attachment modes of the diaphragm 201 and the magnetic flux sensor 10 according to the present embodiment. FIG. 4A is a perspective view showing the toner storage unit 200 before the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 4B is a perspective view showing the toner container 200 to which the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 4C is a top view showing the toner storage unit 200 to which the vibration plate 201 and the magnetic flux sensor 10 are attached. FIG. 4D is a cross-sectional view taken along the cutting line BB of FIG.

The modes shown in FIGS. 4A to 4D are mounting modes by fitting into ribs that are recesses. Therefore, as shown in FIG. 4A, a rib 200a is provided on an inner wall of the housing of the toner storage unit 200, and a rib 200b is provided on an outer wall thereof.

Then, as shown in FIG. 4A, the vibration plate 201 is fixed to the inside of the housing of the toner storage unit 200 by fitting the vibration plate 201 into the rib 200 a. Further, as shown in FIG. 4D, the magnetic flux sensor 10 is fitted into the rib 200b, so that the magnetic flux sensor 10 is fixed to the outside of the housing of the toner containing unit 200.

Also in the modes shown in FIGS. 4A to 4D, it is possible to prevent the toner from scattering by not providing the through hole in the housing of the toner storage unit 200. Further, it is also the same that the work of fastening the screw is unnecessary and the assembling work becomes easy. Further, it is also possible to reduce the cost by reducing the number of parts such as the fastening member and the seal member.

Here, in the example of FIGS. 4A to 4D, as shown in FIGS. 4A and 4D, the upper end of the pedestal holding the diaphragm 201 is flat with a hook shape. A section 210 is provided. In other words, the flat portion 210 is a structural portion for forming a surface that is substantially perpendicular to the fitting direction when the diaphragm 201 is fitted in the rib 200a.

Accordingly, when the diaphragm 201 is attached to the rib 200a, the flat portion 210 serves as a pressed portion to be pressed by the operator. Therefore, the worker can press the flat portion 210 to push the diaphragm 201 into the rib 200a, and the mounting work can be facilitated.

Although not shown in FIG. 4D, the magnetic flux sensor 10 may be provided with a configuration corresponding to the flat portion 210 of the diaphragm 201. Thereby, the work of pushing the magnetic flux sensor 10 into the rib 200b can be facilitated. According to the modes of FIGS. 4A to 4D, it is possible to reduce the number of adhesive layers as compared with the modes of FIGS. 3A to 3D, so that the cost is further reduced and the work is facilitated. Can be planned.

Moreover, you may combine the aspect by the adhesion shown in FIG.3(a)-(d) and the aspect by the fitting shown in FIG.4(a)-(d). For example, a mode in which the vibration plate 201 is attached and the magnetic flux sensor 10 is attached by fitting, or a mode in which the vibration plate 201 is inserted and the magnetic flux sensor 10 is attached by adhesion can be considered.

Further, in the modes shown in FIGS. 3A to 3D and FIGS. 4A to 4D, by mounting the pedestal on the vibration plate 201, the wall surface of the casing of the toner storage unit 200 and the vibration plate 201. Has secured an interval with. However, this is an example, and a structure corresponding to a pedestal may be provided depending on the shape of the inside of the housing of the toner storage unit 200, and the vibration plate 201 may be attached to the structure.

Next, the internal configuration of the magnetic flux sensor 10 according to the present embodiment will be described with reference to FIG. As shown in FIG. 5, the magnetic flux sensor 10 according to the present embodiment is an oscillation circuit based on a Colpitts type LC oscillation circuit, and includes a plane pattern coil 11, a pattern resistor 12, a first capacitor 13, and a second capacitor 14. , A feedback resistor 15, unbuffer ICs 16 and 17, and an output terminal 18.

The plane pattern coil 11 is a plane coil formed by signal lines patterned in a plane on the substrate that constitutes the magnetic flux sensor 10. As shown in FIG. 5, the planar pattern coil 11 has an inductance L obtained by the coil. In the planar pattern coil 11, the value of the inductance L changes due to the magnetic flux passing through the space facing the plane where the coil is formed. As a result, the magnetic flux sensor 10 according to the present embodiment is used as an oscillating unit that oscillates a signal having a frequency according to the magnetic flux passing through the space where the coil surfaces of the plane pattern coil 11 face each other.

The pattern resistor 12 is a resistor configured by a signal line patterned in a plane shape on the substrate similarly to the plane pattern coil 11. The pattern resistor 12 according to the present embodiment is a pattern formed in a zigzag shape, which creates a state in which current does not easily flow as compared with a linear pattern. Providing the pattern resistor 12 is one of the gist of the present embodiment. In addition, the zigzag shape is, in other words, a shape bent so as to reciprocate a plurality of times in a predetermined direction. As shown in FIG. 5, the pattern resistor 12 has a resistance value R _P. As shown in FIG. 5, the plane pattern coil 11 and the pattern resistor 12 are connected in series.

The first capacitor 13 and the second capacitor 14 are capacitors that form a Colpitts LC oscillator circuit together with the plane pattern coil 11. Therefore, the first capacitor 13 and the second capacitor 14 are connected in series with the plane pattern coil 11 and the pattern resistor 12. A resonance current loop is formed by a loop formed by the plane pattern coil 11, the pattern resistor 12, the first capacitor 13, and the second capacitor 14.

The feedback resistor 15 is inserted to stabilize the bias voltage. Due to the functions of the unbuffer IC 16 and the unbuffer IC 17, a change in the potential of a part of the resonance current loop is output from the output terminal 18 as a rectangular wave corresponding to the resonance frequency.

With such a configuration, the magnetic flux sensor 10 according to the present embodiment oscillates at the frequency f according to the inductance L, the resistance value R _P , and the capacitance C of the first capacitor 13 and the second capacitor 14. The frequency f can be expressed by the following equation (1).

The inductance L also changes depending on the presence and concentration of the magnetic substance near the plane pattern coil 11. Therefore, it is possible to determine the magnetic permeability in the space near the plane pattern coil 11 based on the oscillation frequency of the magnetic flux sensor 10.

In addition, as described above, the magnetic flux sensor 10 in the toner storage unit 200 according to the present embodiment is arranged to face the diaphragm 201 via the housing. Therefore, the magnetic flux generated by the plane pattern coil 11 passes through the diaphragm 201. That is, the diaphragm 201 affects the magnetic flux generated by the planar pattern coil 11 and affects the inductance L. As a result, the presence of the diaphragm 201 affects the frequency of the oscillation signal of the magnetic flux sensor 10. This is one of the gist of the present embodiment. Details will be described later.

FIG. 6 is a diagram showing an aspect of the count value of the output signal of the magnetic flux sensor 10 according to the present embodiment. In principle, the magnetic flux sensor 10 continues to oscillate at the same frequency unless the magnetic flux generated by the plane pattern coil 11 included in the magnetic flux sensor 10 is changed. As a result, as shown in FIG. 6, the count value of the counter uniformly increases as time elapses, and as shown in FIG. 6, at the timings of t1, t2, t3, t4, and t5, aaaah, bbbbbh. , Ccccch, ddddh, and AAAAh are acquired.

The count value at the timing of each, by calculating on the basis of _{T 1, T 2, T 3} , T 4 periods each shown in FIG. 6, the frequency in the period each is calculated. For example, when a reference clock corresponding to 2 (msec) is counted and an interrupt signal is output to calculate a frequency, the count value in each period is divided by 2 (msec) to obtain T1, T2, The oscillation frequency f (Hz) of the magnetic flux sensor 10 in each period of T3 and T4 is calculated.

Further, as shown in FIG. 6, when the upper limit of the count value of the counter is FFFFh, the sum of the value obtained by subtracting ddddd from FFFFh and the value of AAAAh is 2 (msec when calculating the frequency in the period T ₄ . It is possible to calculate the oscillation frequency f (Hz) by dividing by.

As described above, in the image forming apparatus 100 according to the present embodiment, the frequency of the signal oscillated by the magnetic flux sensor 10 can be acquired, and the event corresponding to the oscillation frequency of the magnetic flux sensor 10 can be determined based on the acquired result. it can. Then, in the magnetic flux sensor 10 according to the present embodiment, the inductance L changes according to the state of the diaphragm 201 arranged so as to face the plane pattern coil 11, and as a result, the signal output from the output terminal 18 is changed. The frequency changes.

As a result, in the controller that obtains the signal, it is possible to confirm the state of the diaphragm 201 that is arranged so as to face the plane pattern coil 11. It is one of the gist of the present embodiment to judge the state of the toner as the color developer inside the toner containing section 200 based on the state of the vibration plate 201 confirmed in this way.

As described above, the frequency is obtained by dividing the count value of the oscillation signal by the period. However, if the period for acquiring the count value is fixed, the obtained count value is used as a parameter for indicating the frequency. It is also possible to use it as it is.

FIG. 7 is a perspective view showing an overview of the magnetic flux sensor 10 according to this embodiment. In FIG. 7, the surface on which the planar pattern coil 11 and the pattern resistor 12 described in FIG. 5 are formed, that is, the detection surface facing the space in which the magnetic permeability is to be detected faces the upper surface.

As shown in FIG. 7, a pattern resistor 12 connected in series with the plane pattern coil 11 is patterned on the detection surface on which the plane pattern coil 11 is formed. As described with reference to FIG. 5, the plane pattern coil 11 is a pattern of signal lines spirally formed on a plane. The pattern resistor 12 is a signal pattern formed in a zigzag shape on a plane, and these patterns realize the function of the magnetic flux sensor 10 described above.

The portion formed by the plane pattern coil 11 and the pattern resistor 12 is the magnetic permeability sensor of the magnetic flux sensor 10 according to this embodiment. When the magnetic flux sensor 10 is attached to the toner containing portion 200, this detecting portion is attached so as to face the diaphragm 201.

Next, a configuration for acquiring the output value of the magnetic flux sensor 10 in the image forming apparatus 100 according to this embodiment will be described with reference to FIG. FIG. 8 is a diagram showing the configurations of the controller 20 and the magnetic flux sensor 10 that acquire the output value of the magnetic flux sensor 10. As shown in FIG. 8, the controller 20 according to the present embodiment includes a CPU (Central Processing Unit) 21, an ASIC (Application Specific Integrated Circuit) 22, a timer 23, a crystal oscillation circuit 24, and an input/output control ASIC 30.

The CPU 21 is an arithmetic means and controls the overall operation of the controller 20 by performing arithmetic operations according to a program stored in a storage medium such as a ROM (Read Only Memory). The ASIC 22 functions as a connection interface between the system bus to which the CPU 21, RAM (Random Access Memory), etc. are connected and other devices.

The timer 23 generates an interrupt signal and outputs it to the CPU 21 each time the count value of the reference clock input from the crystal oscillation circuit 24 reaches a predetermined value. The CPU 21 outputs a read signal for acquiring the output value of the magnetic flux sensor 10 according to the interrupt signal input from the timer 23. The crystal oscillator circuit 24 oscillates a reference clock for operating each device inside the controller 20.

The input/output control ASIC 30 acquires the detection signal output from the magnetic flux sensor 10 and converts it into information that can be processed inside the controller 20. As shown in FIG. 8, the input/output control ASIC 30 includes a magnetic permeability counter 31, a read signal acquisition unit 32, and a count value output unit 33. As described above, the magnetic flux sensor 10 according to the present embodiment is an oscillation circuit that outputs a rectangular wave having a frequency according to the magnetic permeability in the space to be detected.

The magnetic permeability counter 31 is a counter that increments a value according to a rectangular wave output from the magnetic flux sensor 10. That is, the magnetic permeability counter 31 functions as a target signal counter that counts the number of target signals whose frequencies are to be calculated. The magnetic flux sensor 10 according to the present embodiment is provided for each toner storage portion 200 connected to the CMYK color developing devices 112, and accordingly, a plurality of magnetic permeability counters 31 are also provided.

The read signal acquisition unit 32 acquires, via the ASIC 22, a read signal that is an instruction to acquire the count value of the magnetic permeability counter 31 from the CPU 21. When the read signal acquisition unit 32 acquires the read signal from the CPU 21, the read signal acquisition unit 32 inputs a signal for causing the count value output unit 33 to output the count value. The count value output unit 33 outputs the count value of the magnetic permeability counter 31 according to the signal from the read signal acquisition unit 32.

The input/output control ASIC 30 is accessed from the CPU 21 via a register, for example. Therefore, the read signal described above is performed by the CPU 21 writing a value to a predetermined register included in the input/output control ASIC 30. The output of the count value by the count value output unit 33 is performed by storing the count value in a predetermined register included in the input/output control ASIC 30, and the CPU 21 acquiring the value. The controller 20 shown in FIG. 8 may be provided separately from the magnetic flux sensor 10, or may be mounted on the substrate of the magnetic flux sensor 10 as a circuit including the CPU 21.

In such a configuration, the CPU 21 detects the vibration state of the diaphragm 201 based on the count value acquired from the count value output unit 33, and detects the toner remaining amount inside the toner containing unit 200 based on the detection result. That is, the detection processing unit is configured by the CPU 21 performing calculation according to a predetermined program. Further, the count value acquired from the count value output unit 33 is used as frequency related information indicating the frequency of the magnetic flux sensor 10 that changes according to the vibration of the diaphragm 201.

Next, the influence of the diaphragm 201 on the oscillation frequency of the magnetic flux sensor 10 according to the present embodiment will be described. As shown in FIG. 9, the surface of the magnetic flux sensor 10 on which the plane pattern coil 11 is formed and the vibration plate 201 are arranged to face each other with the housing of the toner storage unit 200 interposed therebetween. Then, as shown in FIG. 9, a magnetic flux is generated around the center of the plane pattern coil 11, and the magnetic flux penetrates the diaphragm 201.

The diaphragm 201 is composed of, for example, a SUS plate, and an eddy current is generated in the diaphragm 201 when the magnetic flux G ₁ penetrates the diaphragm 201 as shown in FIG. 10. This eddy current generates a magnetic flux G ₂ and acts so as to cancel the magnetic flux G ₁ by the plane pattern coil 11. By canceling the magnetic flux G1 in this way, the inductance L in the magnetic flux sensor 10 decreases. As shown in the above equation (1), when the inductance L decreases, the oscillation frequency f increases.

The strength of the eddy current generated inside the diaphragm 201 in response to the magnetic flux of the plane pattern coil 11 changes depending on the strength of the magnetic flux and the distance between the plane pattern coil 11 and the diaphragm 201. FIG. 11 is a diagram showing the oscillation frequency of the magnetic flux sensor 10 according to the distance between the plane pattern coil 11 and the diaphragm 201.

The strength of the eddy current generated inside the diaphragm 201 is inversely proportional to the distance between the plane pattern coil 11 and the diaphragm 201. Therefore, as shown in FIG. 11, the oscillating frequency of the magnetic flux sensor 10 becomes higher as the distance between the plane pattern coil 11 and the diaphragm 201 becomes narrower, and when it becomes narrower than the predetermined distance, the inductance L becomes too low and oscillates. Will not do.

Therefore, the oscillation frequency is zero in the interval of g ₀ or less. On the other hand, when the distance between the plane pattern coil 11 and the diaphragm 201 becomes wider, the oscillation frequency of the magnetic flux sensor 10 converges to a frequency that is not affected by the eddy current generated inside the diaphragm 201.

In the toner storage unit 200 according to this embodiment, the vibration of the diaphragm 201 is detected based on the oscillation frequency of the magnetic flux sensor 10 by utilizing the characteristics shown in FIG. The gist of the present embodiment is to detect the amount of toner remaining in the toner storage unit 200 based on the vibration of the diaphragm 201 detected in this way. That is, the diaphragm 201 and the magnetic flux sensor 10 shown in FIG. 9 and the configuration for processing the output signals of the magnetic flux sensor 10 are used as the powder detection device according to the present embodiment. This powder detecting device is a developer remaining amount detecting device if used for detecting the remaining amount of toner. Further, the magnetic flux sensor 10 functions as an oscillating unit.

The vibration of the vibration plate 201 repelled by the stirring member 205 is represented by a natural frequency determined by the rigidity of the vibration plate 201 and the weight of the weight 202, and a damping rate determined by an external factor that absorbs the vibration energy. As external factors that absorb the vibration energy, in addition to fixing factors such as a fixing strength of a fixing portion that fixes the vibration plate 201 in a cantilever state, air resistance, and the like, the vibration plate 201 contacts the vibration plate 201 inside the toner containing unit 200. There is toner.

The toner that comes into contact with the vibration plate 201 inside the toner container 200 varies depending on the remaining amount of toner inside the toner container 200. Therefore, by detecting the vibration of the vibration plate 201, it is possible to detect the amount of toner remaining in the toner storage unit 200. Therefore, inside the toner storage unit 200 according to the present embodiment, the stirring member 205 for stirring the toner inside repels the vibration plate 201, and periodically vibrates the vibration plate 201 according to the rotation.

Next, the arrangement of parts around the vibration plate 201 inside the toner storage unit 200 and the configuration for the stirring member 205 to repel the vibration plate 201 will be described. FIG. 12 is a perspective view showing a positional relationship around the diaphragm 201. As shown in FIG. 12, the vibration plate 201 is fixed to the housing of the toner storage unit 200 via a fixing unit 201a that is a pedestal.

FIG. 13 is a side view showing a rotating state of the rotating shaft 204 before the stirring member 205 contacts the weight 202 attached to the vibration plate 201. In FIG. 13, the rotating shaft 204 rotates so that the stirring member 205 rotates clockwise.

As shown in FIG. 13, the weight 202 is a protruding portion that protrudes from the plate surface of the diaphragm 201, and has a shape that is inclined with respect to the plate surface of the diaphragm 201 when viewed from the side. This inclination is configured such that the inclined surface approaches the rotation shaft 204 along the rotation direction of the stirring member 205. The inclined surface of the weight 202 is a portion that is pushed by the stirring member 205 when the stirring member 205 repels and vibrates the diaphragm 201. FIG. 14 is a side view showing a state in which the stirring member 205 is further rotated from the state shown in FIG.

When the stirring member 205 further rotates while being in contact with the weight 202, the diaphragm 201 is pushed and deformed due to the inclination provided on the weight 202. In FIG. 14, the positions of the diaphragm 201 and the weight 202 in a state where no external force is applied (hereinafter, referred to as “steady state”) are indicated by broken lines. As shown in FIG. 14, the vibration plate 201 and the weight 202 are pushed in by the stirring member 205.

FIG. 15 is a top view showing the state shown in FIG. Since the vibration plate 201 is fixed to the inner wall of the housing of the toner storage unit 200 via the fixed portion 201a, the position on the fixed portion 201a side does not change. On the other hand, the end portion on the opposite side where the weight 202 is provided and which is the free end moves to the side opposite to the side where the rotary shaft 204 is provided by being pushed in by the stirring member 205. As a result, the diaphragm 201 bends from the fixed portion 201a as a base point as shown in FIG. In such a bent state, energy for vibrating the diaphragm 201 is stored.

As shown in FIG. 15, the stirring member 205 according to the present embodiment is provided with a cut 205a between a portion in contact with the weight 202 and a portion other than the portion. Accordingly, it is possible to prevent the stirring member 205 from being damaged due to an excessive force applied when the stirring member 205 pushes the weight 202.

A round portion 205b is provided at the starting point of the cut 205a. This makes it possible to disperse the stress applied to the starting point of the notch 205a when the amount of bending of the agitator 205 differs from the notch 205a as a boundary, and to prevent damage to the agitator 205.

FIG. 16 is a side view showing a state where the stirring member 205 is further rotated from the state shown in FIG. In FIG. 16, the position of the diaphragm 201 in the steady state is shown by a broken line, and the position of the diaphragm 201 shown in FIG. 14 is shown by a chain line. The solid line indicates the position of the vibration plate 201 that is bent toward the opposite side by releasing the vibration energy that has been pushed in and stored by the stirring member 205.

FIG. 17 is a top view showing the state shown in FIG. As shown in FIG. 16, when the pressing of the weight 202 by the stirring member 205 is released, the bending energy stored in the diaphragm 201 causes the end portion on the side where the weight 202, which is a free end, is provided to the opposite side. Move to flex.

In the state shown in FIGS. 16 and 17, the vibration plate 201 is in a state away from the magnetic flux sensor 10 which is opposed via the housing of the toner containing unit 200. After that, the vibration plate 201 vibrates to return to the steady state by damping the vibration while repeating the state closer to the magnetic flux sensor 10 than the steady state and the state farther from the steady state.

FIG. 18 is a diagram schematically showing the state of the toner held inside the toner storage unit 200 by dots. As shown in FIG. 18, when toner is present inside the toner storage unit 200, the vibration plate 201 and the weight 202 vibrate and come into contact with the toner. Therefore, the vibration of the vibration plate 201 is attenuated earlier than when the toner does not exist inside the toner storage unit 200. It is possible to detect the amount of toner remaining in the toner storage unit 200 based on the change in the vibration attenuation.

FIG. 19 is a diagram showing changes in the count value of the oscillation signal of the magnetic flux sensor 10 for each predetermined period until the vibration of the diaphragm 201 is attenuated and stopped after the weight 202 is repelled by the stirring member 205. is there. The count value of the oscillation signal of the magnetic flux sensor 10 increases as the oscillation frequency increases. Therefore, the vertical axis of FIG. 19 can be replaced with the oscillation frequency instead of the count value.

As shown in FIG. 19, at timing t ₁ , the stirring member 205 contacts the weight 202 and pushes in the weight 202, so that the vibration plate 201 approaches the magnetic flux sensor 10. As a result, the oscillation frequency of the magnetic flux sensor 10 increases and the count value for each predetermined period increases.

Then, at timing t ₂ , the pressing of the weight 202 by the stirring member 205 is released, and thereafter, the diaphragm 201 vibrates due to the stored vibration energy. When the diaphragm 201 vibrates, the gap between the diaphragm 201 and the magnetic flux sensor 10 is repeatedly centered around a steady state, a wider state and a narrower state. As a result, the frequency of the oscillation signal of the magnetic flux sensor 10 vibrates with the vibration of the diaphragm 201, and the count value for each predetermined period also vibrates.

The vibration amplitude of the diaphragm 201 becomes narrower as the vibration energy is consumed. That is, the vibration of the diaphragm 201 attenuates with time. Therefore, the change in the interval between the diaphragm 201 and the magnetic flux sensor 10 also becomes smaller over time, and as shown in FIG. 19, the change in the count value with time also changes.

Here, as described above, the vibration of the vibration plate 201 is attenuated faster as the amount of toner remaining in the toner storage unit 200 increases. Therefore, it is possible to recognize how the vibration of the diaphragm 201 is attenuated by analyzing the mode of damping the vibration of the oscillation signal of the magnetic flux sensor 10 as shown in FIG. You can know the remaining amount.

Therefore, if the vibration peaks of the count value are P1, P2, P3, P4,... As shown in FIG. 19, for example, the vibration damping ratio ζ of the vibration plate 201 is calculated by the following equation (2). Can be asked. By referring to the ratio of the peak values at different timings as shown in the equation (2), it is possible to cancel the error due to the environmental change and obtain the accurate attenuation rate. In other words, the CPU 21 according to the present embodiment obtains the damping rate ζ based on the ratio of the count values acquired at different timings.

In the above formula (2), P ₁ , P ₂ and P ₅ , P ₆ among the peaks shown in FIG. 19 are used, but this is an example, and other peaks may be used. However, the peak value at the timing t ₂ when the vibration plate 201 is pushed in by the stirring member 205 and is closest to the magnetic flux sensor 10, the error such as the superposition of the sliding noise due to the friction between the stirring member 205 and the weight 202 may occur. Since it is included, it is preferably not included in the calculation target.

Even if the vibration is attenuated earlier due to the presence of the toner inside the toner container 200 as shown in FIG. 18, the vibration frequency of the diaphragm 201 does not change significantly. Therefore, by calculating the ratio of the amplitude of the specific peak as shown in the above formula (2), the attenuation of the amplitude in the predetermined period can be calculated.

Next, the operation of detecting the remaining amount of toner in the toner storage unit 200 according to this embodiment will be described with reference to the flowchart of FIG. The operation of the flowchart shown in FIG. 20 is the operation of the CPU 21 shown in FIG. As shown in FIG. 20, the CPU 21 first detects that the weight 202 is pushed by the stirring member 205 as shown in FIG. 14 to generate vibration (S2001).

As described above, the CPU 21 acquires the count value of the output signal of the magnetic flux sensor 10 from the count value output unit 33 every predetermined period. This count value is C ₀ in the steady state, as shown in FIG. On the other hand, when the weight 202 is pushed in as shown in FIG. 14, the count value increases as the diaphragm 201 approaches the magnetic flux sensor 10. Therefore, the CPU 21 detects that vibration has occurred in S2001 when the count value acquired from the count value output unit 33 exceeds a predetermined threshold value.

Regardless of before and after S2001, the CPU 21 continuously performs the count value acquisition process for each predetermined period as a normal process. Then, after S2001, the CPU 21 acquires the peak value of the vibration of the count value according to the vibration of the diaphragm 201 as shown in FIG. 19 (S2002). In S2002, the CPU 21 specifies the peak value by continuously analyzing the count value acquired every predetermined period.

FIG. 21 is a diagram showing an analysis mode of the count value. Regarding the count value acquired every predetermined period, in addition to the “number n” and “count value S _n ”of each count value, the immediately preceding count value is added. The sign “S _n−1 −S _n ”of the difference between and is shown in the order of acquisition. In the result as shown in FIG. 21, the value immediately before the sign of “S _n−1 −S _n ”is inverted is the peak value. In the case of FIG. 21, Nos. 5 and 10 are adopted as peak values.

That is, the CPU 21 calculates “S _n−1 −S _n ”shown in FIG. 21 for the count values sequentially acquired after S2001. Then, the “count value S _n ”at the timing when the sign obtained as the calculation result is inverted is adopted as the peak value such as P ₁ , P ₂ , P ₃ ... Shown in FIG.

Incidentally, as described above, it is preferable to avoid the value at the timing t ₂ . The value of the timing t ₂ is the first peak after S2001. Therefore, the CPU 21 discards the first value among the peak values extracted by performing the analysis as shown in FIG.

Further, the count value actually obtained may include noise of a high frequency component, and the timing at which the sign of “S _n−1 −S _n ”is inverted at a position other than the peak due to the vibration of the diaphragm 201. May occur. In order to avoid erroneous detection in such a case, it is preferable that the CPU 21 perform smoothing processing on the value acquired from the count value output unit 33 and then perform the analysis shown in FIG. In the smoothing process, a general process such as a moving average method can be adopted.

When the peak value is acquired in this way, the CPU 21 calculates the damping rate ζ by the calculation of the above formula (2) (S2003). Therefore, in S2002, the count value is analyzed in the mode shown in FIG. 21 until the peak value used for the calculation of the attenuation rate is obtained. When using the above formula (2), the CPU 21 analyzes the count value until the peak value corresponding to P ₆ is obtained.

When the damping rate ζ is calculated in this way, the CPU 21 determines whether the calculated damping rate ζ is equal to or less than a predetermined threshold value (S2004). That is, the CPU 21 determines that the toner inside the toner storage unit 200 has fallen below a predetermined amount, based on the magnitude relationship between the ratio of the count values acquired at different timings and the predetermined threshold value. As described with reference to FIG. 18, when a sufficient amount of toner remains inside the toner storage unit 200, the vibration of the vibration plate 201 is quickly attenuated. Therefore, the damping rate ζ becomes small.

On the other hand, when the amount of toner in the toner storage unit 200 decreases, the damping of the vibration of the diaphragm 201 slows accordingly, and the damping rate ζ increases. Therefore, by setting the attenuation rate ζ _S corresponding to the remaining amount of toner to be detected as a threshold value, the remaining amount of toner inside the toner storage unit 200 should be detected based on the calculated attenuation rate ζ. It is possible to judge that the amount has decreased to the “specified amount”).

It should be noted that the amount of toner remaining inside the toner storage unit 200 does not directly affect the vibration damping mode of the vibration plate 201, but the contact state of the toner with respect to the vibration plate 201 changes according to the amount of toner remaining, which causes vibration. The mode of damping the vibration of the plate 201 is determined. Therefore, even if the amount of remaining toner in the toner storage unit 200 is the same, if the contact mode of the toner with respect to the vibration plate 201 is different, the damping mode of the vibration plate 201 is different.

On the other hand, when the remaining amount of toner inside the toner storage unit 200 according to the present embodiment is detected, the toner inside the toner storage unit 200 is constantly stirred by the stirring member 205. Therefore, the contact state of the toner with the vibration plate 201 can be determined to some extent according to the remaining amount of toner. Accordingly, it is possible to avoid the adverse effect that the detection result is different due to the different contact mode of the toner to the vibration plate 201 even if the remaining amount of toner is the same.

As a result of the determination in S2004, if the calculated attenuation rate ζ is less than the threshold value (S2004/NO), the CPU 21 determines that a sufficient amount of toner is held inside the toner storage unit 200, and the process is performed as it is. finish. On the other hand, if the calculated attenuation rate ζ is greater than or equal to the threshold value (S2004/YES), the CPU 21 determines that the toner amount in the toner storage unit 200 is below the specified amount, detects toner depletion, and ends the process. Yes (S2005).

The CPU 21, which has detected toner depletion in the process of S2005, outputs a signal indicating that the remaining amount of toner has fallen below the specified amount to a higher-level controller that controls the image forming apparatus 100. As a result, the controller of the image forming apparatus 100 can recognize the toner exhaustion for a specific color.

Next, the relationship between the frequency of the oscillation signal of the magnetic flux sensor 10 according to the present embodiment, the count value acquisition cycle by the CPU 21 (hereinafter referred to as “sampling cycle”), and the natural frequency of the diaphragm 201 will be described. FIG. 22 is a diagram showing sampled count values for the vibration of the diaphragm 201 for one cycle. In FIG. 22, the vibration period of the diaphragm 201 is T _plate and the sampling period is T _sample .

In order to calculate the damping ratio ζ of the diaphragm 201 with high accuracy in the manner described with reference to FIGS. 19 to 21, it is necessary to acquire the peak value of the vibration of the diaphragm 201 with high accuracy. For that purpose, the number of samples of a sufficient count value for T _plate is required, and therefore T _sample needs to be sufficiently small for T _plate .

In the example of FIG. 22, the number of samples of the count value is 10 for one cycle of T _plate . That is, T _sample is 1/10 of T _plate . According to the aspect of FIG. 22, sampling is always performed within the period of T _{peak in} the figure, and the peak value can be acquired with high accuracy.

Therefore, assuming that the sampling cycle T _{sample of the} CPU 21 is 1 ms, the vibration cycle T _plate of the diaphragm 201 is preferably 10 ms or more. In other words, with respect to the sampling frequency of 1000 Hz of the CPU 21, the natural frequency of the diaphragm 201 is preferably about 100 Hz, more preferably less than that. Such a natural frequency of the diaphragm 201 is realized by adjusting the material of the diaphragm 201, the dimensions including the thickness of the diaphragm 201, and the weight of the weight 202.

On the other hand, if the value of the count value sampled in each sampling cycle is too small, the change in the count value for each sample according to the vibration of the diaphragm 201 becomes small, and the damping rate ζ cannot be calculated accurately. Here, the value of the sampled count value is a value according to the oscillation frequency of the magnetic flux sensor 10.

Generally, the oscillation frequency of the magnetic flux sensor 10 is on the order of several MHz, and when sampling is performed at a sampling frequency of 1000 Hz, a count value of 1000 or more can be obtained at each sampling timing. Therefore, the damping ratio ζ can be calculated with high accuracy by the order of T _plate and T _sample as described above.

However, if the amount of change in the oscillation frequency of the magnetic flux sensor 10 is not sufficient with respect to the change in the distance between the magnetic flux sensor 10 and the diaphragm 201 due to the vibration of the diaphragm 201, the count value with respect to time as shown in FIG. The vibration amplitude becomes smaller. As a result, the change in the damping ratio ζ also becomes small, and the accuracy of the remaining toner amount detection due to the vibration of the diaphragm 201 also deteriorates.

In order to increase the amount of change in the oscillation frequency of the magnetic flux sensor 10 with respect to the change in the distance between the magnetic flux sensor 10 and the diaphragm 201, the arrangement of the magnetic flux sensor 10 and the diaphragm 201 based on the characteristics shown in FIG. It is necessary to determine the interval. For example, as shown by the arrowed section in the figure, the gap between the magnetic flux sensor 10 and the diaphragm 201 is set such that the gap in which the change in the oscillation frequency with respect to the change in the gap between the magnetic flux sensor 10 and the diaphragm 201 is steep is included. It is preferable to determine the interval.

FIG. 23 is a diagram showing an adjustment mode of the arrangement interval between the magnetic flux sensor 10 and the diaphragm 201. As shown in FIG. 23, the gap g between the magnetic flux sensor 10 and the diaphragm 201 is adjusted by adjusting the thickness of the casing of the toner containing unit 200 to which the magnetic flux sensor 10 and the diaphragm 201 are attached, or by fixing the diaphragm 201. The thickness can be adjusted by the thickness of the fixing portion 201a.

As described above, according to the method for detecting the remaining amount of toner according to the present embodiment, the influence of toner on the delicate phenomenon of vibration of the diaphragm 201 is detected. Further, unlike the mode of directly detecting the pressure of the toner and the like, the pressure of the toner is detected through the vibration of the vibrating plate, so that it is possible to increase the remaining amount of the toner in the container without using a pressure sensor or the like whose accuracy is difficult to improve. It is possible to detect with high accuracy.

Further, it is premised that the diaphragm 201 to be sensed by the magnetic flux sensor 10 used as the sensor in the present embodiment is vibrating. Therefore, even if the toner adheres to the vibration plate 201, the adhered toner is shaken off by the vibration, and it is possible to avoid a decrease in the detection accuracy due to the adherence of the toner.

Further, no physical contact is required between the magnetic flux sensor 10 used as the sensor in this embodiment and the diaphragm 201 to be sensed. Therefore, even if the magnetic flux sensor 10 is provided outside the toner container, it is not necessary to make a hole in the housing of the container to secure physical access. Therefore, it can be easily attached and productivity can be improved.

Further, according to the aspect of the present embodiment, the detection of the remaining amount of toner is triggered by the displacement of the vibration plate 201 pressed by the stirring member 205 as in S2001, and after obtaining the peak value thereafter. Executed. Therefore, when the vibration plate 201 is pushed by the stirring member 205 as shown in FIG. 14, the detection result of the toner remaining amount cannot be obtained.

On the other hand, in a case where the pressure sensor or the like detects the pressure according to the remaining amount of toner, the pressure applied by the stirring member that stirs the toner in the container and the pressure generated according to the remaining amount of toner are It is difficult to distinguish and it is difficult to improve the detection accuracy. According to the aspect of the present embodiment, such a problem can be solved.

In the above embodiment, the case where the diaphragm 201, which is a plate-shaped member made of a metal material, is used as an object to be sensed by the magnetic flux sensor 10 has been described as an example. However, this is an example. The condition required for the diaphragm 201 is to generate vibration at a predetermined frequency as described with reference to FIG. 22 and to influence the magnetic flux in accordance with the change in the distance from the magnetic flux sensor 10, and It is to influence the frequency.

In the above-described embodiment, the metal material that cancels out the magnetic flux and decreases the inductance L as it gets closer to the magnetic flux sensor 10 is used, but conversely, the ferromagnetic material that increases the magnetic flux and increases the inductance L as it gets closer to the magnetic flux sensor 10. The material of is also good.

In the above embodiment, the diaphragm 201, which is a plate-shaped member, is the sensing target of the magnetic flux sensor 10 from the viewpoint of affecting the magnetic flux generated by the plane pattern coil 11 of the magnetic flux sensor 10 and the viewpoint of natural frequency. However, this is only an example, and as long as the conditions of vibrating and affecting the magnetic flux are satisfied, a rod-shaped component may be used instead of the plate-shaped component.

Further, in the above-described embodiment, the mode in which the diaphragm 201 is formed by using the material that affects the magnetic flux and the damping of the vibration of the diaphragm 201 is detected by the magnetic flux sensor 10 has been described as an example. However, this is merely an example, and any mode may be used as long as the amount of toner remaining in the container is detected by the influence of the toner on the delicate phenomenon of damping the vibration of the plate member.

Further, it is possible to adjust the above-mentioned specified amount by disposing the vibration plate 201 and the magnetic flux sensor 10 in the toner storage unit 200. 24 and 25 are diagrams showing the relationship between the arrangement of the vibration plate 201 and the magnetic flux sensor 10 in the toner storage unit 200 and the specified amount. In the case of FIG. 24, when the height of the toner held inside the toner storage unit 200 becomes lower than the height of the broken line A shown in the drawing, the toner does not come into contact with the vibration plate 201. Therefore, in the vicinity of the height of the broken line A in the figure, it is detected that the remaining toner amount is below the specified amount.

On the other hand, in the case of FIG. 25, the arrangement height of the diaphragm 201 and the magnetic flux sensor 10 is lower than that in FIG. When the height of the toner held inside the toner storage unit 200 becomes lower than the height of the broken line B shown in the figure, the toner does not come into contact with the vibration plate 201. Therefore, in the vicinity of the height of the broken line B in the figure, it is detected that the remaining toner amount is below the specified amount.

The mode in which the specified amount is adjusted by the arrangement of the vibration plate 201 and the magnetic flux sensor 10 as described above can be used, for example, to adjust the supply state of the toners of each color of CMYK. For example, for a color that is frequently used among CMYK, the diaphragm 201 and the magnetic flux sensor 10 are arranged relatively high as shown in FIG. On the other hand, for colors that are used less frequently, the diaphragm 201 and the magnetic flux sensor 10 are arranged relatively low as shown in FIG. By such adjustment, it becomes possible to efficiently supply the toner according to the frequency of use.

Further, in the above-described embodiment, the toner which is the color developer used in the electrophotographic image forming apparatus has been described as an example of the powder of which the remaining amount is to be detected. However, this is just an example, and it is similarly applicable if it is a powder that has fluidity and affects the vibration of the vibration plate 201 according to the remaining amount, for example, a premix in which toner and carrier are mixed in advance. It is applicable to agents. Further, not only the powder, but any substance that has fluidity and affects the vibration of the vibration plate 201 depending on the remaining amount can be similarly detected as the remaining amount, and the target is the liquid. It is also possible to adopt.

Further, in the above embodiment, the case where the damping rate ζ is calculated by the above equation (2) has been described as an example. However, this is an example, and the average value of the attenuation rates between a plurality of peaks may be used, for example, as in the following Expression (3).

Further, as shown in the following formula (4), the ratio of the peak value may be simply used.

Moreover, in the said embodiment, the case where the plane pattern coil formed by patterning on a board|substrate was used as an example was demonstrated. By forming the coil on a flat surface, it is possible to reduce the thickness in the direction facing the diaphragm 201, which is the object of sensing, and it is possible to suitably achieve miniaturization of the device.

However, even if the coil is not formed in the plane pattern, the same effect can be obtained by forming the coil so that the magnetic flux is generated in parallel to the direction facing the diaphragm 201. 26 and 27 show another example of the coil formation mode. FIG. 26 is a diagram viewed from a direction parallel to the plate surface of the substrate forming the magnetic flux sensor 10, and FIG. 27 is a diagram viewed from a direction perpendicular to the plate surface of the substrate forming the magnetic flux sensor 10.

In the example of FIGS. 26 and 27, the coil 11 ′ is formed by winding and arranging the wiring whose surface is insulated on the substrate that constitutes the magnetic flux sensor 10. Also in the examples of FIGS. 26 and 27, the thickness of the coil 11 ′ can be made sufficiently thin by appropriately selecting the type of wiring, and the device can be downsized.

Further, in the above embodiment, as shown in FIG. 2, the all-in-one type process cartridge having no function of further supplying the toner to the toner storage portion 200 has been described as an example. However, this is only an example, and the present invention can be applied to, for example, a toner replenishment type process cartridge in which a toner cartridge for replenishing the toner in the toner storage unit 200 is detachable. Such an example will be described with reference to FIG.

FIG. 28 is a side sectional view showing a toner replenishment type process cartridge. As shown in FIG. 28, the structure of the process cartridge is almost the same as that of the all-in-one type described in FIG. Further, in the toner replenishment type process cartridge, the toner cartridge 220 for supplying the toner to the toner containing portion 200 is configured to be removable.

As shown in FIG. 28, also in the toner replenishment type process cartridge, the magnetic flux sensor 10 and the vibration plate 201 are provided in the toner containing section 200 to detect the amount of toner inside the toner containing section 200. With such a configuration, it is possible to detect the amount of toner remaining inside the toner storage unit 200 as in the above case. Further, the process cartridge is replaced less frequently than the toner cartridge 220. Therefore, by providing the magnetic flux sensor 10 and the vibration plate 201 on the toner storage unit 200 side instead of the toner cartridge 220, the frequency of replacement of the magnetic flux sensor 10 and the vibration plate 201 can be reduced, and the cost can be reduced.

Embodiment 2.
In the first embodiment, the case where the magnetic flux sensor 10 is attached to the process cartridge has been described as an example. In the present embodiment, the case where the magnetic flux sensor 10 is attached to the main body side of the image forming apparatus 100 will be described as an example. In addition, about the structure attached|subjected with the same code|symbol as Embodiment 1, it shows the same or an equivalent part, and detailed description is abbreviate|omitted.

FIG. 29 is a side sectional view showing the configuration around the image forming unit 106 configured as a process cartridge in the image forming apparatus 100 according to this embodiment. As shown in FIG. 29, the positional relationship between the vibration plate 201 and the magnetic flux sensor 10 in the toner storage unit 200 is the same as that in the first embodiment. The magnetic flux sensor 10 according to the present embodiment is different from that of the first embodiment in that it is attached not to the process cartridge side but to the main body side of the image forming apparatus 100.

FIG. 30 is a side sectional view showing a state in which the process cartridge is removed from the main body of the image forming apparatus 100. As shown in FIG. 30, a sensor holding portion 10 a is provided in a portion of the image forming apparatus 100, to which the process cartridge is attached, facing the toner containing portion 200.

A pressing portion 10c is connected to the sensor holding portion 10a via an elastic body 10b. The magnetic flux sensor 10 is attached to the pressing portion 10c. The elastic body 10b is made of an elastic material such as rubber or spring, and when the process cartridge is removed, the pressing portion 10c is pushed out of the sensor holding portion 10a by the elastic force of the elastic body 10b.

When the process cartridge is attached to the main body of the image forming apparatus 100, the magnetic flux sensor 10 attached to the pressing portion 10c is pressed against the process cartridge by the elastic force of the elastic body 10b, as shown in FIG. As a result, similarly to the first embodiment, the vibration of the diaphragm 201 can be detected by the magnetic flux sensor 10.

FIG. 31 is a side sectional view showing an example in the case of the toner replenishment type process cartridge described in FIG. In the case of FIG. 31 as well, as in FIG. 29, the sensor holding portion 10a is provided at a position facing the toner containing portion 200 at the position where the process cartridge is attached.

FIG. 32 is a side sectional view showing a state in which the process cartridge with the toner cartridge 220 attached is removed from the apparatus main body. As shown in FIG. 32, when the process cartridge is removed, the pressing portion 10c is pushed out from the sensor holding portion 10a by the elastic force of the elastic body 10b.

When the process cartridge is attached as shown in FIG. 31, the magnetic flux sensor 10 is pressed against the process cartridge by the pressing portion 10c via the elastic force of the elastic body 10b, and is arranged so as to face the internal diaphragm 201. .. As a result, similarly to the first embodiment, the vibration of the diaphragm 201 can be detected by the magnetic flux sensor 10.

The process cartridge is positioned with respect to the apparatus main body, and is fixed to a predetermined position when attached to the apparatus main body. Therefore, the vibration plate 201 and the magnetic flux sensor 10 included in the process cartridge are determined in advance by determining the positions of the magnetic flux sensor 10 attached to the sensor holding portion 10a and the pressing portion 10c according to the fixed position of the process cartridge. It becomes the positional relationship. As a result, it is possible to avoid a detection error due to the displacement between the diaphragm 201 and the magnetic flux sensor 10.

FIG. 33 is a diagram showing a positioning mode of the process cartridge. A guide rail 300 as a main body side positioning portion is provided at a position where the process cartridge is attached in the main body of the apparatus. In FIG. 33, the guide rail 300 provided on the apparatus main body side is shown by the hatched area.

A convex portion including the rotation axis of the photosensitive drum 109 projects axially from the process cartridge on both sides, and the convex portion functions as a positioning portion on the process cartridge side. Specifically, as shown in FIG. 33, the process cartridge is mounted on the apparatus main body side such that the above-mentioned convex portion moves along the guide rail 300 provided on the main body side. Then, the above-mentioned convex portion abuts on the terminal end portion of the guide rail 300, whereby the process cartridge is positioned in the apparatus main body, and the mounting is completed. Then, at this time, the tip portion in the mounting direction of the process cartridge is in a state of abutting against the magnetic flux sensor 10.

In such a positioning mode of the process cartridge, the positional accuracy of the guide rail 300 and the magnetic flux sensor 10 in the apparatus main body is increased in advance so that the vibration plate 201 included in the process cartridge when the process cartridge is mounted is The positional accuracy with respect to the magnetic flux sensor 10 can be improved.

FIG. 34 is a diagram showing an example in the case of the toner replenishment type process cartridge described in FIGS. 31 and 32. Also in this case, the process cartridge is mounted on the apparatus main body side so that the convex portion of the process cartridge moves along the guide rail 300 provided on the apparatus main body side, similarly to the positioning mode described with reference to FIG. It

10 magnetic flux sensor 10a sensor holding part 10b elastic body 10c pressing part 11 planar pattern coil 12 pattern resistor 13 first capacitor 14 second capacitor 15 feedback resistor 16, 17 unbuffer IC
18 Output terminal 20 Controller 21 CPU
22 ASIC
23 Timer 24 Crystal Oscillation Circuit 30 Input/Output Control ASIC
31 Permeability Counter 32 Read Signal Acquisition Unit 33 Count Value Output Unit 101 Paper Feed Tray 102 Paper Feed Roller 103 Registration Roller 104 Paper 105 Transport Belt 106K, 106C, 106M, 106Y Image Forming Unit 107 Drive Roller 108 Driven Roller 109K, 109C, 109M, 109Y Photosensitive drum 110K, 110C, 110M, 110Y Charging device 111 Optical writing device 112, 112K, 112C, 112M, 112Y Developing device 112a Developing roller 112b Developing blade 112c Supply roller 113K, 113C, 113M, 113Y Photosensitive cleaner 115K , 115C, 115M, 115Y Transfer device 116 Fixing device 117 Toner bottle 118 Belt cleaner 200 Toner accommodating portion 200a, 200b Rib 201 Vibration plate 201a Fixing portion 202 Weight 204 Rotating shaft 205 Stirring member 205a Cut 205b Round portion 210 Flat portion 220 Toner Cartridge 300 Guide rail

JP, 2013-37280, A

Claims (12)

A stirring unit that is housed in a housing unit of a developing device that develops an electrostatic latent image formed on an image carrier, is fixed to a shaft that rotates inside the housing unit, and rotates inside the housing unit. A developer remaining amount detecting device for detecting the remaining amount of the developer stirred by,
An oscillating unit that outputs a signal of a frequency according to the state of the magnetic flux passing through the opposing space,
The oscillator is disposed inside the accommodating portion, faces the oscillating portion through the housing of the accommodating portion, and is oscillated in a direction facing the oscillating portion by being released from the state displaced by the rotation of the stirring portion. And a vibrating part made of a material that affects the magnetic flux,
Obtaining frequency-related information about the frequency of the oscillation signal of the oscillating unit in a predetermined cycle, detecting the vibration state of the oscillating unit based on the change of the frequency-related information that changes according to the vibration of the oscillating unit, A developing agent remaining amount detection device, comprising: a detection processing unit that detects the remaining amount of the developing agent inside the storage unit based on a vibration state. The vibrating section and the oscillating section are arranged so as to face each other via the housing of the accommodating section,
The developer according to claim 1, wherein a space in which the vibrating portion is arranged and a space in which the oscillating portion is arranged are blocked in a direction in which the vibrating portion and the oscillating portion face each other. Remaining amount detection device. At least one of the vibrating section and the oscillating section is attached to the housing of the accommodating section by adhesion, and the color developer residual amount detecting device according to claim 1 or 2. At least one of the vibrating part and the oscillating part is fitted into the recess of the housing of the accommodating part, and is attached to the housing, and the color developer residual amount detecting device according to claim 1 or 2. One of the vibrating portion and the oscillating portion, which is fitted into and attached to the recess of the housing of the accommodating portion, is constituted by a surface substantially perpendicular to the direction of fitting into the recess and is fitted into the recess. The developer remaining amount detecting device according to claim 4, further comprising a pressed portion that is pressed at the time. The developer remaining amount detecting device according to claim 1, wherein the developer is a toner. Imaging equipment for a developer residual amount detecting device is mounted according to any one of claims 1 to 6. A stirrer fixed to a shaft that rotates inside an accommodating portion that accommodates a developer and stirring inside the accommodating portion to stir the developer, and a space that is attached to the outer wall of the accommodating portion and faces each other. An oscillating unit that outputs a signal having a frequency according to the state of the magnetic flux passing through, and acquires frequency-related information regarding the frequency of the oscillating signal of the oscillating unit at a predetermined cycle to detect the remaining amount of the color developer. A developing device that is attached to and detached from an image forming apparatus having a detection processing unit that
It is formed of a material that affects magnetic flux and is arranged inside the accommodating portion, and when the developing device is attached to the image forming apparatus, faces the oscillation portion through the housing of the accommodating portion. Along with, a vibrating section that vibrates in a direction facing the oscillating section by being released from a state displaced by the rotation of the stirring section,
The detection processing unit detects the vibration state of the vibration unit based on the change in the frequency-related information that changes according to the vibration of the vibration unit, and based on the vibration state, the color developer of the inside of the containing unit. A developing device characterized in that the remaining amount is detected. An image forming apparatus comprising the developing device according to claim 8 . In a process cartridge in which an image carrier, a charging device, a cleaning device, and a developing device are integrally detachable from an image forming apparatus,
A process cartridge comprising the developing device according to claim 8 . An image forming apparatus comprising the process cartridge according to claim 10. A stirring unit that is housed in a housing unit of a developing device that develops an electrostatic latent image formed on an image carrier, is fixed to a shaft that rotates inside the housing unit, and rotates inside the housing unit. A method for detecting the remaining amount of the developer, which detects the remaining amount of the developer stirred by
The oscillation unit outputs a signal of a frequency according to the state of the magnetic flux passing through the opposing space,
The oscillator is disposed inside the accommodating portion, faces the oscillating portion through the housing of the accommodating portion, and is oscillated in a direction facing the oscillating portion by being released from the state displaced by the rotation of the stirring portion. And vibrate the vibrating part formed by the material that affects the magnetic flux,
Obtaining frequency-related information about the frequency of the oscillation signal of the oscillation unit in a predetermined cycle,
Detecting a vibration state of the vibrating unit based on a change in the frequency related information that changes according to the vibration of the vibrating unit,
A method for detecting a remaining amount of a color developer, which is configured to detect the remaining amount of the color developer inside the housing portion based on the vibration state.