JP2610119B2 - Image recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for recording an information image on recording paper.

[0002]

2. Description of the Related Art As an image recording apparatus for recording an information image on a recording sheet, there is known a printer using a laser light source and having a control device for converting code information into an image signal. This control device is arranged at a lower part in the image recording device.

[0003]

However, in the above-described image recording apparatus, since the control substrate is disposed in the lower portion of the image recording apparatus, the developer scattered from the developing means, the cleaning means, and the like, is left on the control substrate. In such a case, a contact failure or the like occurs and the control board becomes inoperable. Further, there is another problem that heat generated from the fixing unit, the power supply unit, or the control board increases the temperature in the image recording apparatus and adversely affects the control board.
Therefore, the present invention solves the above-described problems, and provides an image recording apparatus that prevents the developer floating in the image recording apparatus from adversely affecting the control substrate and prevents the adverse effect due to a rise in the temperature of the control substrate. The purpose is to:

[0004]

According to a first aspect of the present invention, at least an image bearing member, a latent image forming unit, a developing unit incorporating toner, a transfer unit, and an image bearing unit are provided on a recording sheet fed from a sheet feeding unit. An image recording apparatus that performs image recording in an image forming unit including a cleaning unit that removes residual toner on the surface of a body, fixes an image on a recording sheet by a fixing unit, and discharges the recording sheet outside the apparatus. A recording paper transport path for transporting the recording paper from the paper feeding unit to the fixing unit, a recording paper discharge path for discharging the recording paper after passing through the fixing unit to a recording paper discharge storage unit, an image forming unit, and recording. A control board disposed substantially parallel to a bottom plate of the image recording apparatus in a space formed below the paper conveyance path and the fixing unit; and an image forming unit.
A first shielding portion disposed between the control substrate and the recording paper transport path and the fixing unit so as to cover an upper portion of the control substrate;
A second shielding portion that hangs down from the periphery of the first shielding portion toward the bottom plate of the image recording apparatus so as to cover a portion other than the upper portion of the control board, and forms a space with the first shielding portion; An air flow path provided in a second shielding portion located upstream of the fixing unit with respect to the recording paper conveyance direction in the conveyance path, the air flow path communicating the space with the outside of the space; And air blowing means for flowing air along the control board inside the space and discharging the air to the outside of the image recording apparatus.

[0005]

According to the first aspect of the present invention, since the control board is disposed substantially parallel to the bottom plate of the image recording apparatus, the height of the image recording apparatus increases even if the size of the control board increases. It can be stored without being made. Further, since the first shielding portion and the second shielding portion are disposed between the image forming portion and the control substrate so as to isolate the control substrate, the first shielding portion and the second shielding portion may be disposed on the control substrate by heat generated in the image forming portion. In addition to preventing heat conduction, the developer scattered from the developing unit and the cleaning unit is prevented from being accumulated on the control substrate. Furthermore, since the air blowing means flows air into the space separated by the first shielding portion and the second shielding portion, the air flowing into the space from the air flow path flows along the control board to form an image. The heat generated from the control board is discharged to the outside of the recording apparatus, and is also discharged to the outside of the image recording apparatus.

[0006]

FIG. 1 shows an example of a printer as an image recording apparatus using a semiconductor laser.
An outline of the recording process performed by the computer is described below. In FIG. 1, recording paper 4 is bundled and stacked on a bottom plate 3 of a paper feed tray 2 partially stored in a printer 1, and the uppermost recording paper 4 is separated and conveyed by a paper feed roller 5. It is sent to the roller pair 6. The separation / conveyance roller pair 6 includes an upper roller 6a and a lower roller 6b, and the lower roller 6b rotates in a direction opposite to the recording paper feeding direction (arrow direction) or is held in a stopped state. When a plurality of recording papers 4 have been sent from the paper feed tray 2, only the uppermost recording paper 4 is separated and conveyed in cooperation with the upper roller 6a rotating in the direction of the arrow shown in the figure. The paper feed tray 2 is still attached to the printer 1, and the recording paper 4 is supplied by rotating and opening the cover 55 around the fulcrum 55 a and sliding the recording paper 4 onto the bottom plate 3. Do.
A push-up lever 66 that pushes up the recording paper 4 in the paper feed tray 2 is provided below the paper feed tray 2. The push-up lever 66 is rotated counterclockwise by a driving force of a motor (not shown) via a reduction gear or the like in a state in which the push-up lever 66 is in contact with the bottom plate 3. It is designed to push up. The recording paper end detection lever 67 in contact with the upper surface of the recording paper 4 falls downward by its own weight when the recording paper 4 runs out, and detects the recording paper end in cooperation with the photo interrupter 68.

The recording paper 4 sent by the recording paper separating / conveying roller pair 6 is continuously fed after reaching the position of the registration roller pair 7, and the leading end of the recording paper 4 reaches the position of the recording paper leading end detection sensor 8. In this state, the registration roller pair 7 temporarily stops, and the recording paper 4 also stops this movement. At this time, the recording paper separating / conveying roller pair 6 also stops. After feeding the recording paper 4 by a predetermined amount, the paper feed roller 5 releases a clutch (not shown) and idles. A paper feed unit is composed of the paper feed tray 2, the recording paper separation / conveyance roller pair 6, the registration roller pair 7, and the like.
It is. Recording from this paper feeding unit to the fixing unit 22 described later
A recording paper transport path for transporting paper 4 is formed continuously from the paper feed unit
Have been.

Above the paper feed tray 2, toner as a developer is stored, and a photosensitive member 15 as an image carrier is stored.
Developing means 47 for supplying toner to the printer is provided. The developing means 47 includes a developing container 48, a toner cartridge 4
9, a toner stirring member 50, a doctor blade 51, a developing sleeve 17, and the like.

Incidentally, inside the printer 1, an optical housing 9 as a latent image forming means is provided on the upper portion thereof, and mirrors 11 and 12 are provided in the optical housing 9 in the position shown in FIG. A semiconductor laser light source (not shown), a holographic scanner, a polygon, and the like are arranged at the back of these mirror systems. In the printer 1 having such an optical system, now, when a print signal from the host machine printer 1 receives a photoreceptor 15 of the endless belt is not adapted to start rotating in the direction of the arrow, to Accompanying
First, the surface of the photoconductor is uniformly charged by the charger 16.

On the other hand, signal light corresponding to image information is emitted from the semiconductor laser light source, and this signal light is converted into scanning light by a rotating holographic scanner or polygon.
This scanning light is guided by mirrors 11 and 12, passes through a cylindrical lens 13, and is applied to a uniformly charged surface of the photoreceptor 15, and due to the accompanying exposure, an electrostatic latent is formed on the surface of the photoreceptor. An image is formed. Reference numeral 14 denotes a dust-proof glass.

The electrostatic latent image thus formed is visualized by toner, which is a one-component developer, carried on the surface of the developing sleeve 17. By the way, as described above, the recording paper 4 temporarily stops once the leading end of the recording paper 4 reaches the position of the recording paper leading end detection sensor 8.
After this stop, the registration roller pair 7 starts rotating again,
The leading end of the recording paper 4 sent toward the photoreceptor 15 by this rotation is aptly associated with the leading end of a visible image on the photoreceptor in a transfer section facing a transfer charger 18 as a transfer unit.

Next, in the transfer section, the photosensitive member 15
The recording paper 4 that moves while contacting the
Transfers the toner image on the photoconductor 15, and thereafter,
The leading edge of the recording paper 4 separates from the photoreceptor due to the strength of its own waist,
Thereafter, the recording paper 4 is sent toward the fixing roller pair 23 of the heat fixing unit 22 while being guided by the guide members 19 and 20. The fixing roller pair 23 has a heat source on at least one of the rollers 23a and 23b. When the recording paper 4 passes between the two rollers, the transferred image on the recording paper 4 is thermally fixed, and this fixing is performed. Thereafter, the recording paper 4 is sent toward the recording paper discharge path 25 including the guide plates 41 and 42 while being peeled off from the surface of the roller 23a by the peeling claw 24. While passing through the paper discharge path 25, the recording paper 4 is inverted by 180 ° and discharged from the paper discharge roller pair 26 with the recording image surface facing downward, and is discharged to a paper discharge tray 27 as a recording paper discharge storage unit. Is stored. On the other hand, the toner remaining on the surface of the photoconductor 15 is removed by the fur brush 29 of the cleaning unit 28, and the photoconductor is cleaned.
Be prepared for the next record. The aforementioned photoreceptor 15, optical housing 9,
An image forming unit includes the developing unit 47, the transfer charger 18, the cleaning unit 28, and the like.

Between the lower part of the image forming unit and the bottom of the printer 1, a shielding wall 70 extending from the base 32 of the printer 1 integrally formed of a synthetic resin or the like forms an upper and lower part of the image recording apparatus 1. A space partitioned in the direction is formed. The shielding wall 70 includes a shielding upper wall 70a as a first shielding portion substantially along the recording paper transport path, and a shielding side wall 70b hanging down from the periphery of the shielding upper wall 70a toward the bottom plate of the image recording apparatus 1. It is formed in a box shape. The illustration of both side walls of the shielding side wall 70b is omitted. The power supply unit 33 as an electrical unit, the control circuit board 34 of the printer 1, the controller 31, the fan device 35 as a blower, and the like are stored in the box-shaped interior formed by the shielding wall 70, that is, in the above-described space. ing. The controller 31
It converts code information into image signals, and has a plurality of control boards 31a and 31b. Control board 3
1a and 31b are substantially parallel to the bottom plate of the image recording apparatus 1.
Each is arranged. In addition to the control boards 31a and 31b of the controller 31 and the control circuit board 34, a related printed board 38 related to the optical system is provided on the upper part of the optical housing 9. In FIG. A pattern storage device 39 is provided.

Above the space in which the controller 31 and the like are arranged is a shield frame 36, and the control boards 31a and 31b
Are covered with metal plates 52, respectively. Metal plate 5
2 is detachably attached to the printer 1 by screws. The control boards 31a and 31b are arranged in space,
Since the signal line is covered with the metal plate 52, the signal line is not exposed, noise is not generated, or the noise is not picked up. As a result, occurrence of malfunction can be avoided, The reliability of the printer 1 can be further improved. The power supply unit 33 and the controller 31 are isolated from each other by a shield frame 36.

Charger 16 and transfer charger 18
And the like, ozone is generated, and the entry of the ozone into the lower space below the shielding upper wall 70a is blocked by the shielding upper wall 70a. Further, the shielding side wall 70b is provided with an air intake opening 37 as an air flow path communicating between the inside of the space in which the control circuit board 34 and the like are stored and the outside 71 of the space. Air intake opening 3
Reference numeral 7 is located upstream of the fixing unit 22 with respect to the recording paper transport direction of the recording paper transport path. In the printer 1, the fan device 35 is operated to flow air from the air intake opening 37 into the space where the control boards 31 a and 31 b are stored. The air that has flowed into the space flows along the control boards 31a and 31b, the control circuit board 34, and the power supply unit 33, and is discharged outside the printer 1. The control board 31a,
31b, the control circuit board 34 and the power supply unit 33 are cooled. In this case, the side 33a of the power supply unit 33,
By forming a part of the side portion 36a of the shield frame 36 into a wire mesh structure, the inside of the power supply unit 33 and the control board 31 are formed.
a, 31b and the like can be further cooled.

In the present invention, as shown in FIG. 2, since the control boards 31c and 31d are arranged at the lower part in the printer 1, the control boards can be arbitrarily added downward as needed. FIG. 2 shows two control boards 31c and 31d.
Is shown, but the number is arbitrary. When the control board layer bulges below the bottom of the apparatus main body with the addition of the control board, long legs 5 as shown by reference numeral 56 are used.
By attaching 6, the height of the printer can be adjusted appropriately.

[0017]

As described above, according to the first aspect of the present invention, even if the size of the control board becomes large, it can be stored without increasing the height of the image recording apparatus. It is possible to prevent an increase in the size of the recording device and reduce the size of the device. Further, since the developer scattered from the developing unit or the cleaning unit is prevented from being accumulated on the control substrate, it is possible to prevent the control substrate from being adversely affected by the developer, and to obtain a stable operation of the control substrate. The reliability of the recording device can be improved. Further, heat conduction to the control board due to heat generated in the image forming unit is prevented, and since air flowing into the space from the air flow path emits heat generated from the control board to the outside of the image recording apparatus, The control board can be prevented from being adversely affected by heat from the image forming unit, particularly the fixing unit, and the control board can also be cooled to improve the durability of the control board.

[Brief description of the drawings]

FIG. 1 is a sectional view of an image recording apparatus showing one embodiment of the present invention.

FIG. 2 is a sectional view of a main part of an embodiment in which a control board is added.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image recording apparatus 2 Paper feed tray 6 Recording paper separation conveyance roller pair 7 Registration roller pair 4 Recording paper 9 Optical system as a latent image forming means 15 Photoconductor as an image carrier 18 Transfer charger as a transferring means 22 Fixing unit 28 Cleaning means 31a, 31b, 31c, 31d Control board 32a Shielding wall as shielding member 35 Fan device as blowing means 47 Developing means

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takashi Yokota 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd. (56) References JP-A-49-1117049 (JP, A) Showa 48-75246 (JP, A) Actually open Showa 54-33708 (JP, U)

Claims (1)

(57) [Claims] 1. A cleaning device for removing at least an image carrier, a latent image forming device, a developing device incorporating toner, a transfer device, and a residual toner on the surface of the image carrier on a recording paper fed from a paper feeding unit. An image forming apparatus configured to perform image recording, fix an image on recording paper by a fixing unit, and then discharge the recording paper out of the apparatus. A recording paper conveyance path for conveying the paper, a recording paper discharge path for discharging the recording paper after passing through the fixing unit to a recording paper discharge storage unit, the image forming unit, the recording paper conveyance path, and the A control board disposed substantially in parallel with a bottom plate of the image recording apparatus in a space formed below the fixing unit; and between the image forming section, the recording paper transport path, and the fixing unit and the control board. ,Before A first shielding portion disposed to cover an upper portion of the control substrate, and a first shielding portion hanging down from a periphery of the first shielding portion to a bottom plate of the image recording apparatus so as to cover a portion other than the upper portion of the control substrate. A second shielding unit that forms the space with the first shielding unit; and a second shielding unit that is positioned upstream of the fixing unit with respect to a recording paper transport direction of the recording paper transport path. An air flow path that communicates the space and the outside of the space, air flows into the space from the air flow path, and flows the air along the control board inside the space. And an air blowing means for discharging the air to the outside of the image recording apparatus.