JPH03282485A - Image forming device - Google Patents

Abstract

PURPOSE:To improve throughput by generating a signal indicating an error state for tentatively interrupting image recording and operating a cleaning mechanism based on an error state display signal. CONSTITUTION:The counted value of a RAM 23 is added at every recording action. When the counted value is a prescribed value, for instance, 1500, a CPU 21 sends an image recording action stopping signal and simultaneously, the driving signal of a motor 19. When the error state such that a paper feeding tray has no sheets, etc., occurs in a device before a counter reaches 1500, the image recording action stopping signal and simultaneously, a motor driving signal are sent from the CPU 21 with a detecting signal from an error detecting sensor 25. At this time, the image recording action is tentatively interrupted, simultaneously, the reversal rotary action of the motor 19 is started, and the cleaning action of a doctor blade is carried out during an image recording action stopping period. Thus, the image recording action only to carry out the cleaning of the doctor blade of a developing unit is almost prevented from being tentatively stopped, and the throughput of the device is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image recording apparatus such as a copying machine, a printer facsimile, etc., which is equipped with a mechanism for cleaning a doctor blade of a developing device.

[Conventional technology]

Generally, in image recording devices such as copying machines, printers, and facsimile machines, a latent image is formed on an image carrier by a print head, etc., and magnetic toner is attached to the surface of a developing roller in the form of spikes on the image carrier. The developing devices are arranged to face each other, and the spike-shaped toner of the developing devices is brought into contact with the image carrier to develop a latent image.

This spike-shaped toner is formed so that the toner stored in the developing device is regulated by a doctor blade and adhered to the sleeve of the developing roller, so that the height of the spike is kept constant. However, if this doctor blade is clogged with toner lumps, spikes of toner are not generated in some areas, resulting in a state in which a portion of the recorded image appears white.

Conventionally, in order to remove the toner lumps, an apparatus has been proposed in which a member is provided for cleaning the tip of a doctor blade disposed opposite to the sleeve of the developing roller. A mechanism has also been proposed in which the cleaning member is operated by a motor at certain time intervals to clean the doctor blade.

[Problem to be solved by the invention]

By the way, in a device equipped with a cleaning mechanism in which the cleaning member is operated by a motor at predetermined time intervals as described above, if the cleaning mechanism is configured to perform the cleaning operation every time 500 images are recorded, for example, the jib When the timing for recording the 500th image comes in the middle of the process, the image recording operation is temporarily stopped and the cleaning operation is started. After the cleaning operation is completed, an operation is performed to start the image recording operation again.

However, when the blade cleaning timing comes in the middle of a job, the image recording operation is temporarily stopped and the blade cleaning is performed, so the image recording operation cannot be performed during the cleaning operation, and the throughput (output amount per unit time) is reduced. ) is a problem that decreases.

The present invention has been made in order to solve the above-mentioned problems in conventional image recording apparatuses. The purpose is to provide a recording device.

[Means and operations for solving the problem] In order to solve the above-mentioned problems, the present invention provides an image recording apparatus having a mechanism for cleaning a doctor blade of a developing device. and means for operating the cleaning mechanism based on the error status display signal.

With this configuration, the cleaning mechanism operates to clean the doctor blade while the recording operation is interrupted in the image recording apparatus due to some reason such as out of paper or stacker full.

Therefore, there are fewer opportunities to stop the image recording operation to perform blade cleaning, and the throughput of the apparatus can be improved.

[Example] Next, an example will be described. FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of the image recording apparatus of the present invention, FIG. 2 is an enlarged bottom view showing the developing unit, and FIG. 3 is a sectional view of FIG. 2. In a certain figure, 1 is an elevator type paper feed tray, 2 is a paper stacked on the paper feed tray 1, and 3 is a paper feed roller that conveys the paper 2 stacked on the paper feed tray 1 to a transfer recording position. , 4 is a print head for forming a latent image on the image carrier 5, 6 is a developing device for developing the latent image formed on the image carrier 5, and 7 is the developed image carrier 5. 8 is a cleaning device for removing residual toner on the image carrier 5 after the transfer, and 9 is a discharge stunning force.

As shown in FIGS. 2 and 3, the developing device 6 is rotatably driven by a drive system (not shown), and includes a sleeve 11 on which toner is attached in the form of spikes, and a spike-shaped toner 12 that is attached to the sleeve 11. a doctor blade I3 having an inclined surface at its tip and disposed opposite to the sleeve 11 in order to maintain a constant height; The hook is movably held on a shaft 16 extending between the frames 15, 15, and is arranged so as to be able to slide along the side surface of the doctor blade 13. A blade cleaner 17 is mounted on the doctor blade cleaner support member 14, with its distal end along the inclined surface and the distal end inclined surface of the doctor blade 13, and its distal end is positioned in the gap between the distal end of the doctor blade 13 and the sleeve 11. It's stuck like that.

The cleaner support member 14 also has a wire 2 wound around a pulley of a motor 19 fixed to the support Fi1B.
One of the two ends of the doctor blade 13 is fixed via a spring 21, and the cleaner support member 14 moves between the left end and the right end in FIG. It is constructed so that it can be cleaned with.

FIG. 4 is a block configuration diagram of the control unit, in which 21 is a CPU that controls the device, 22 is a ROM in which a control program is written, 23 is a RAM that stores a count value of the number of recorded sheets, 24 is a peripheral interface, 25 is a group of sensors for detecting error states of the device. When the error detection sensor 25 detects an error state such as out of paper, the CPU 21 sends a drive signal for the motor 19 along with an image recording operation stop signal, and the image recording operation is interrupted and the motor 19 is rotated for 5 seconds at a time. The doctor blade 13 is driven in the reverse direction, and the blade cleaner 17 performs a cleaning operation of the doctor blade 13. Further, the count value of the RAM 23 is charged for each recording operation, and when the count value reaches a predetermined value, for example, 1500, the CPU 21 similarly sends out a drive signal for the motor 19 together with an image recording operation stop signal. ing.

Next, the operation of the image recording apparatus configured as described above will be explained. First, when the power of the apparatus is turned on, the motor 19 is driven to clean the doctor blade 13 of the developing unit 6, as shown in the flowchart of the program that generates the blade cleaning timing of the CPU that controls the entire apparatus as shown in FIG. is performed, and the count value of the counter of the RAM 23 that generates the cleaning timing is set to O.

Next, when you start the recording operation, paper 2 is inserted from paper feed tray L.
is fed by the paper feed roller 3 toward the transfer recording position. In synchronization with the feeding of the paper 2, a latent image is formed on the image carrier 5 by the print head 4, and this latent image is transferred to the developing device 6.
The toner image is developed into a toner image, which is transferred onto the paper 2 by a transfer roller at the transfer recording position, and the transferred paper 2 is discharged and stacked on the stacker 9. On the other hand, residual toner is removed from the image carrier 5 by a cleaning device 8.
One image recording cycle is completed and the next image recording operation is awaited.

In this way, each time one image is recorded, the counter counts up, and when the counter reaches 1500, the apparatus is temporarily stopped, the motor 19 is rotated in the forward and reverse directions, and the doctor blade 13 of the developing unit 6 is rotated. A cleaning operation is performed, whereby the cleaner support member 14 holding the blade cleaner 17 moves from the left end home position to the right end, and then returns to the left end home position, and the blade cleaner 17 moves between the sleeve 11 and the doctor blade. 13 to remove toner lumps clogging the gap.

If an error condition occurs in the apparatus, such as the paper feed tray 1 being out of paper or the stacker 9 being full, before the counter reaches 1500, the CPU 21 sends an image recording operation stop signal based on the detection signal from the error detection sensor 25. A motor drive signal is sent.

As a result, the image recording operation is temporarily interrupted, and the motor 19 starts to operate in forward and backward directions, and the cleaning operation of the doctor blade 13 is performed during the period when the image recording operation is stopped. When this cleaning operation of the doctor blade 13 is performed, the counter is reset and waits for the next image recording operation. Since the time required for cleaning the doctor blade 13 by reciprocating the blade cleaner 17 is about 10 seconds, the blade cleaning operation can be completed before the operator clears the error state.

In this embodiment, the maximum loading capacity of the elevator-type paper feed tray l is 1200 sheets, so if a method of replenishing 1200 sheets of paper is used after the paper runs out, the paper will run out. A cleaning operation of the doctor blade will be carried out only at certain times. If a method is used in which paper is added to the paper feed tray after several hundred images have been recorded, the apparatus will temporarily stop after recording 1,500 images and perform a doctor blade cleaning operation.

In this manner, the image recording operation of the image recording apparatus is almost never temporarily stopped just for cleaning the doctor blade of the developing device, so that the throughput of the image recording apparatus is improved.

In the above embodiment, the cleaning mechanism is operated when the number of recorded sheets reaches a predetermined value, but the recording time is counted and the cleaning mechanism is operated when the recording leap reaches a predetermined time. It may be configured as follows. Furthermore, the cleaning operation based on error detection can be performed not only when there is no paper or when the stacker is full, but also when a paper jam is detected.

〔Effect of the invention〕

As described above based on the embodiments, according to the present invention, the cleaning mechanism of the doctor blade is operated based on the signal indicating the error layer that temporarily stops the image recording operation. The doctor blade is cleaned while the image recording operation is paused due to an error condition such as Error Condition, thus reducing the chance of stopping the image recording operation just to clean the doctor blade and improving the throughput of the device. can be done.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of an image recording apparatus according to the present invention, FIG. 2 is an enlarged bottom view showing the configuration of the developing unit, and FIG. FIG. 4 is a block diagram of the control section, and FIG. 5 is a flowchart showing the operation for generating cleaning timing. In the figure, 1 is a paper feed tray, 2 is paper, 3 is a paper feed roller, 4 is a print head, 5 is an image carrier, 6 is a developing device, 7 is a transfer roller, 8 is a cleaning device, 9 is a stacker, 1
1 is a sleeve, 12 is a spike-shaped toner, 13 is a doctor blade, 14 is a doctor blade cleaner holding member, 17 is a blade cleaner, 19 is a motor, and 20 is a wire.

Claims (1)

[Scope of Claims] 1. In an image recording apparatus having a mechanism for cleaning a doctor blade of a developing device, means for generating a signal indicating an error state for temporarily interrupting image recording; 1. An image recording device comprising: means for operating a cleaning mechanism. 2. The image recording device according to claim 1, further comprising:
An image recording apparatus comprising: means for counting recording time or the number of recorded sheets; and means for operating the cleaning mechanism when the counting means counts a predetermined value.