JPH0358115B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developing device, and more particularly to a developing device that replenishes developer from a developer replenishing chamber to a developing chamber.

The present invention provides a replenishing means for replenishing the developing chamber with developer from a developer storage chamber, a detecting means S-1 for detecting the amount of developer in the developing chamber, and a detecting means for detecting the amount of developer in the developer storing chamber. In a developing device equipped with S-2, sensors S-1 and S-2 or replenishment means may malfunction, or developer may block in the developer storage chamber, resulting in leakage to the developing chamber. The purpose of the detection means S is to prevent damage to equipment when smooth replenishment of developer becomes impossible.
When the detection signal S-1 is output, the replenishing means is operated to replenish the developer into the developing chamber, and after a predetermined period of time has elapsed since the detection signal S-1 is output, the replenishment means S-1 activates the replenishment means to replenish the developing chamber with developer. To provide a developing device characterized in that, when the developer is not present and the detection means S-2 indicates that there is developer, the image forming device is rendered inactive or an abnormality is displayed.

Examples of the present invention will be described below.

The embodiment shown on the same page is a phenomenon device using a one-component magnetic phenomenon agent. As shown in FIG. 1, this developing device consists of a replenishment toner storage chamber 1 and a developing chamber 2.
A shutter 5 is provided in a communication path 3 between the two chambers 1 and 2 to cause an appropriate amount of toner 4 to be dropped and supplied to the developing chamber 2. Further, a stirring member 6 is provided in the storage chamber 1 near the communication path 3.

In the developing chamber 2, there is a gap between a toner supply sleeve 8 containing a fixed magnet roller 7 and a developing sleeve 10 containing a fixed magnet roller 9.
They are arranged side by side so that they can rotate freely in the same direction at the same speed with d ₂ in between. A blade 11 is arranged with respect to the sleeve 8 with a gap _d1 of 1 mm, for example. This blade 11 is made of a non-magnetic material such as aluminum, and is attached to the partition plate 12 of the two chambers 1 and 2 with a set screw 13. sleeve 10
is opposed to the image forming member (photosensitive drum) 15 at the opening 14 of the developing chamber 2 with a gap _d3 of, for example, 300μ.

The sleeves 8 and 10 are made of a non-magnetic material such as stainless steel, and as shown in FIG. In this configuration, a gear 19 integrated with the shaft 8a of the sleeve 8 is interlocked via a shaft 8a. As the gear 16 rotates in the direction of the arrow, the sleeves 8 and 10 rotate in the direction of the arrow.

The toner adhered to the surface of the rotating sleeve 8 by the magnetic force (N ₂ ') of the magnet roller 7 is regulated by the blade 11 to a uniform thickness of about 1.2 m/m. The adhering toner on this sleeve 8 is
0, the magnet roller 7
The repulsive magnetic force (S ₁ ') of the magnet roller 9, the attractive magnetic force (N ₁ ) of the magnet roller 9, and the electrostatic attractive force of the bias voltage applied to the sleeve 10 by the series-connected DC power supply DC and AC power supply AC. Under the action, it transfers onto the sleeve 10 and forms a thin layer of about 50μ. At a position facing the photosensitive drum 15, the toner on the sleeve 10 is transferred onto the photosensitive drum by receiving the electrostatic attraction force of the latent image formed on the photosensitive drum 15.
The above-mentioned latent image is developed by the jumping development method described in JP-A-55-18656-9.

The toner remaining on the sleeve 10 is separated from the sleeve by the repulsive magnetic force (S ₂ ) of the magnet roller 9, and moves on the inclined bottom surface of the developing chamber 2 in the direction of the dotted arrow.

When the sensor S-1 as a toner remaining amount detection means provided at the bottom of the developing chamber detects a lack of toner in the developing chamber, in response to the detection signal, the solenoid SL-2 shown in FIG. 2 is turned on, and the lever 20 axis 2
Rotate counterclockwise using 1 as the rotation center axis.
As a result, the arm 22 is rotated counterclockwise (in FIG. 1) around the rotating shaft 23 by pulling the dowel 22a engaged with the U groove 20a of the lever 20, and is attached to the rotating shaft 23. The shutter 5 is opened to supply and drop the toner 4 from the replenishment toner storage chamber 1 into the developing chamber 2. On the other hand, when the solenoid SL-2 is turned on, the bent portion 20b of the lever 20 rotates the arm 24 counterclockwise to release the arm 24 from the controller 25.

When the controller 25 becomes free in FIG. 2, a clutch (not shown) is engaged and the rotation of the gear 26 is transmitted to the shaft 6a of the stirring member 3, and the rotation of the stirring member 6 scrapes the toner into the communication path 3.

The above gear 26 is connected to the arm 2 by the controller 25.
When it is stopped at position 4, it is idly rotating on the shaft 6a. As mentioned above, solenoid SL-2 is connected to shaft 6a.
It can be used for timing both the rotation of the shutter 5 and the opening/closing operation of the shutter 5.

In the above configuration, when the sensor S-1 in the developing chamber 2 detects that the amount of toner is low, the solenoid SL-2 turns ON in response to the detection signal from the sensor S-1, and the toner storage chamber 1 is refilled. From there, toner is replenished as described above. Sensor S-
When the supply reaches level 1, the signal from sensor S-1 disappears and solenoid S-2 turns OFF.
Toner supply stops. At that time, if the copy button 105 is pressed and the copying machine is in copy mode, copying is started.

The reason why the developing device is divided into the replenishment toner storage chamber 1 and the developing chamber 2 as described above is that when the developing device is operated with a large amount of toner replenished in the developing chamber 2, the toner in the lower part of the developing chamber is drained from above. This is because it is easily blocked by the weight of the toner. In particular, magnetic toner has a heavy weight per unit volume and is prone to flocking. In addition, frictional heat is generated due to the rotation of the sleeve 8, and the gap d ₁ between the blade 11 and the sleeve 8
When the toner passes through the toner, deterioration of the toner and changes in the triboelectric characteristics are likely to occur.

Therefore, it is better to put the minimum necessary amount of toner in the developing chamber 2 and replenish the toner into the developing chamber each time it is consumed to a certain extent, so that fresh toner can always be used for development. ,
It is economical because the amount of toner that is mixed with foreign matter and thrown away is small.

The amount of toner remaining in the replenishment toner storage chamber is determined by sensor S.
-2 is detected. When the sensor S-2 detects that the amount of toner is running low, a lamp 27 lights up on the operation panel of the copying machine shown in FIG. 3 to indicate where the toner storage chamber 1 is running out of toner. As a method for detecting the presence or absence of toner, this sensor uses, for example, a vibrator, and detects whether or not toner is on the vibrator based on a change in the vibration mode of the vibrator. In addition, a sensor S-2 consisting of a lamp 28 and a light receiving element 29 shown in FIG.
The presence or absence of toner inside is detected.

However, toner detection is prone to malfunction, and the sensor itself is also prone to failures, disconnections, and other accidents. For example, when sensor S-1 detects that the amount of toner in developing chamber 2 is low and replenishes toner from storage chamber 1, the detection signal of sensor S-1 disappears even after a certain period of time has passed. If not, and the sensor S-2 indicates that there is toner in the storage chamber 1, the following accident may occur.

1...Failure of sensor S-1, 2...Failure of sensor S-2, 3...Toner blocks in the storage chamber and is not replenished.In particular, in the case of accident 1, a large amount of toner is sent into the developing chamber, causing solidified toner. Otherwise, toner may enter the bearing and damage the equipment, resulting in a fatal accident.

Therefore, in the present invention, the remaining amount detection sensors S-2 and S-1 in the storage chamber 1 and the developing chamber 2 and a timer circuit are used. ) does not disappear,
When the sensor S-2 indicates that there is toner, the copying operation is stopped and an abnormality is displayed.

FIG. 5 shows a sequence diagram of the developing device of the present invention. In the sequence diagram shown in the figure, when the power is turned on, sensors S-1 and S-2 detect the presence or absence of toner, and when S-2 detects that there is toner and S-1 detects that there is no toner, Solenoid SL-2 operates and starts toner replenishment. When toner replenishment begins, a 4-second timer circuit checks the presence or absence of toner every 4 seconds.

In this developing device according to an embodiment of the present invention, it is set so that an appropriate amount can be replenished in about 4 seconds, but it may be short, long, or continuous. 4
If sensor S-1 remains out of toner after every second and sensor S-2 also out of toner, toner needs to be refilled, and toner replenishment lamp 27
lights up. If sensor S-2 detects that there is toner, even though 4 seconds have passed, sensor S-2
It is strange that -1 remains out of toner, so in this case, the copying operation is stopped, the abnormality lamp 44 is turned on, or the power is turned off.
Of course, it is preferable to perform all three operations as shown. Incidentally, an abnormal location may be displayed on the display 41, which normally indicates the number of copies. After 4 seconds have passed, when sensor S-1 detects that there is toner, turn off solenoid SL-2,
Shift to copy operation. (Step) When both sensors S-2 and S-1 detect the presence of toner, it is checked whether the copy button is pressed or not, and then the copy operation is started. After a predetermined number of copies have been made, the copying operation is stopped. (Step) When both S-2 and S-1 detect that there is no toner, the toner replenishment lamp 27 is turned on. Also, S-
If there is no toner in 2, and if there is toner in S-1, the toner replenishment lamp 27 blinks. (Step) In the developing device according to the present invention, the toner sensor S-2
Even if the printer detects that there is no toner, the developing chamber 2 is configured to contain enough developer to copy 99 sheets or more, and does not check for toner during the copying operation. This is because the sensor may malfunction due to vibration or the amount of toner hitting the sensor may change, and if the copy machine stops due to an out-of-toner signal, the sequence after recovery becomes complicated. After counting the number of sheets, I check whether or not there is toner. In other words, in such a copying machine, even if the toner runs out during the copying operation, if the number of copies is set to 99, the presence or absence of toner in the developing chamber is detected after copying 99 copies, and if there is no toner, the solenoid SL- 2 is turned ON to replenish toner, and when toner replenishment is completed after 4 seconds, copying operation is enabled, and if toner replenishment is not completed, the toner replenishment lamp or error lamp is turned on.

In the developing device according to the present invention, as shown in the sequence diagram of FIG. 5, the sensor S-1 checks the presence or absence of toner every 99 sheets at maximum, that is, after the copying operation is completed.
Even if there is almost no replenishment toner in the storage chamber 1, no problem occurs because there is enough toner in the developing chamber 2 to make 99 or more copies. If you turn on the out-of-toner lamp when 99 copies or more can be copied, it is recommended that you replenish toner in the cartridge when the lamp turns on, so that you do not have to worry about the copying machine stopping due to running out of toner while copying. This has the advantage of being freed from the hassle of having to remember the copy machine sequence and how many copies the operator has made.

Further, in the developing device according to the present invention, if the sensor S
Even if -2 is out of toner, if the toner sensor S-1 in the developing device 2 indicates that there is toner, copying is of course possible. At this time, if the toner replenishment lamp blinks, and when both are out of toner, the toner replenishment lamp will be on and off, etc. If the display method is completely differentiated, the operator will know that the toner is running low, and the toner supply lamp will be turned on and off as soon as possible. It is convenient for the operator because it allows replenishment. That is, in this example, due to the size and cost of the display panel, the display is shared, and the display blinks when there is toner only in sensor S-1, which is closer to the developing area, and lights up when there is no toner in both. However, for example, an additional display may be provided to indicate that the toner is low, or it may be displayed in a different color.

In addition, in FIG. 1, the refill toner storage container 3
0 is a cylindrical inner tube 31 having an opening 31a and a cylindrical outer tube 32 having an opening 32a, which are rotatably fitted together. Since guide convex shapes 33a and 33b are formed asymmetrically on the outer surface of the outer cylinder 32, when the replenishment toner storage container 30 is loaded into the replenishment toner storage chamber 1, the opening 32a always faces downward. Therefore, after loading, the replenishment toner in the middle cylinder 31 is dropped into the storage chamber 1 by rotating the middle cylinder 31 so that its opening 31a matches the opening 32a. 34 is a shaft rotatably provided at the center of the inner cylinder 31, and 35 is a toner scraping member such as a wire attached to the shaft 34.

In FIG. 2, 36 is a protruding shaft of the end face of the inner cylinder 31 passing through the end face of the outer cylinder 32, and 37 is a protruding shaft 3.
This is the engagement member provided at 6. Refill toner storage container 3
0 into the storage chamber 1, the engaging member 37 is inserted in the direction of the U groove 38 on the storage chamber side plate, and after loading, the inner cylinder 31 is inserted so that the opening 31a is aligned with the opening 3 as described above.
By rotating to match 2a,
The engaging member 37 engages with the storage chamber side plate in the direction shown by the chain line, and prevents the replenishment toner storage container 30 from being removed while the toner is being discharged.

In FIG. 3, 40 is a warning display section, 41 is a sheet number display section, 41 is a cassette display section, and 43 is a copy operation section.

As described above, the present invention detects the toner in the toner storage chamber and the developing chamber separately, and when an abnormality occurs, the abnormality is displayed or the operation of each device is immobilized. Equipment is no longer damaged due to breakdowns, etc.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of the developing device of the present invention, FIG. 2 is a side view of the developing device showing the power transmission system, and FIG.
4 is a cross-sectional view of a portion of the replenishment toner storage chamber showing means for detecting the presence or absence of toner, and FIG. 5 is a sequence diagram. 1 is a replenishment toner storage chamber, 2 is a developing chamber, 3 is a communication path, 4 is toner, 5 is a shutter, 6 is a stirring member,
7 and 9 are magnet rollers, 8 and 10 are sleeves, 11 is a blade, 12 is a partition plate, 15 is a photosensitive drum, and S-1 and S-2 are sensors for detecting the presence or absence of toner.

Claims (1)

[Claims] 1. A replenishing means for replenishing the developing chamber with developer from the developer storage chamber, a detecting means S-1 for detecting the amount of developer in the developing chamber, and a detecting means S-2 for detecting the amount of developer in the developing chamber. When the detection signal of the detection means S-1 is output, the replenishment means is activated to replenish the developing chamber with developer, and after a predetermined period of time has elapsed since the detection signal was output. ,
the detection means S-1 indicates a state in which there is no developer;
A developing device characterized in that, when the detecting means S-2 indicates that there is developer, an abnormality display is displayed to disable the image forming device.