JPH0617122Y2 - Image forming device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a charger cleaner device for an electrostatic copying machine.

[Prior Art] Toners and foreign substances are likely to adhere to the charge wire in the charging device of the copying machine and the inner surface of the casing due to long-term use. Further, if the charge wire is contaminated, the discharge becomes unstable or the image quality deteriorates. It was badly affecting other units.

Therefore, a cleaning device is provided for dirt on the charger, but since this operation was operated manually by a service person or user, the contamination state during cleaning is not constant, and time and labor are required for maintenance. It was something that required.

[Object] The present invention provides an image forming apparatus provided with a cleaner device that reliably and automatically cleans dirt of a plurality of charge wires and a casing provided in a copying machine.

[Configuration] In order to achieve the above object, the present invention is configured as follows.

A plurality of chargers having a cleaning member for cleaning the charge wire or the shield member, a unit for bringing the cleaning member into contact with the wire or the shield member, and a moving unit for moving the contact unit along the wire or the shield member. In an image forming apparatus equipped with a cleaning device that operates the cleaning members of a plurality of chargers at different times to clean the wires or shield members of a plurality of chargers, a unit for detecting the temperature of the fixing unit and an image forming unit. When the detection means detects that the temperature is equal to or lower than a predetermined value when the power of the apparatus main body is turned on, a means for activating the moving means and a fixing temperature during cleaning of the wire or the shield member by the operation of the moving means If the value reaches the specified value, after cleaning the wire or shield member being cleaned, the next wire or seal Image forming apparatus having a control means for controlling not to perform the cleaning of the member.

<Embodiment> An embodiment according to the present invention will be described with reference to the drawings.

When the print key of the operation unit of the copying machine shown in FIG. 1 is turned on, the main motor rotates and the drum 1 starts, and at the same time, the photoconductor drum 1 is charged by the charging charger 2. Then, the eraser 3 releases charges other than the copy size.

Next, the light from the illumination unit 4 illuminates the document, and the reflected light is erased on the photosensitive drum 1 via the first mirror 5, the second mirror 6, the third mirror 7, the lens, and the fourth mirror 8. The part that did not exist is illuminated and an electrostatic latent image of the document is formed there. This electrostatic latent image is developed by the developing unit 9, and the toner image is transferred from the first tray 11 or the second tray 12 selected by the transfer unit 10 onto the paper which is fed by the registration rollers 13 at the same timing. Transcribed. The sheet on which the image is transferred has the image fixed by the fixing unit 14 and is ejected to the copy receiving unit 15. On the other hand, the toner residue remaining on the drum 1 is cleaned by the cleaning unit 16, the photosensitive drum is further discharged by the discharging lamp 17, and is charged again by the charging charger 2 to shift to the next copying operation.

In the figure, reference numeral 18 denotes a pre-transfer charger, 19 denotes a separation charger, and 20 denotes a pre-cleaning charger, which are provided around the photosensitive drum 1.

A charger cleaner is provided in each charger to clean the charge wire and the inner surface of the casing. The charger cleaner shown in FIG. 2 is a cleaner installed in the charging charger 2.

In the figure, a charge wire 22 is stretched in a casing 21 in a state of being connected to an electrode 23. Also, pulleys at both ends
A cleaning member (cleaner) 26 is swingably attached to one side of the cleaner wire 25 hung over 30.
The cleaner wire 25 is driven by the motor 27, and the cleaner 26 slides in the casing 21 as the cleaner wire 25 moves left and right to clean the charge wire 22 and the casing inner surface 24 while contacting them.

The movement of the cleaner 26 is controlled as follows.
The cleaner 26 moves along with the cleaner wire 25, and stops at the end thereof by the stopper 28 on the electrode 23 side (A side). At this time, the cleaner wire 25 drive motor 27 is locked and a lock signal is output. After a certain period of time, the cleaner wire 25 drive motor 27 is driven in the opposite direction to the previous time to slidably move the cleaner 26 to the motor 27 side (B side) and stopped by the stopper 29. Furthermore, the motor 27 is driven in the opposite direction to the previous time, the cleaner 26 is moved to the A side, and when the cleaner 26 is stopped by the stopper 28,
It is designed to stop the motor 27.

Although only the cleaner for the charging charger has been described here, the pre-transfer charger 18, the transfer charger 1
0, the separation charger 19, and the pre-cleaning charger 20 also have cleaners of similar structure, and their movement and action are similar.

Next, the cleaner control circuit of the copying machine will be described with reference to FIG.

First of all, the input signal includes a switch SW ₁ (a switch for switching between the power-on state and the number of copies) and a switching SW ₂ (a switch for operating the power-on period and also depending on the number of copies). Signal, reset SW (switch for resetting abnormality detection flag)
Signal, a thermistor signal for detecting the fixing temperature, and a manual SW input signal for manually operating the charger cleaner. The thermistor signal is set so that the change in resistance value with temperature of the thermistor can be detected.
It is input via the / D converter. The above input signals are input to the microcomputer. This microcomputer has a ROM (Read On Memory), RA
It is composed of M (random max memory) and CPU (central processing unit). In particular, RAM is a non-volatile memory backed up by a battery.

Next, a motor drive circuit for operating the charger cleaner is connected to each charger output port, and forward rotation output and reverse rotation output are connected to one motor, and the input signal from the motor drive circuit is connected. Lock signal is being input. Further, an abnormality indicator is provided to give a warning by the abnormality detection signal of the charger cleaner.

Next, a motor drive circuit for directly operating the charger cleaner will be described with reference to FIG.

When a normal rotation signal to _{"1", Q 7, Q 1, Q} 2, Q 6 is applied a positive voltage to the + side of the motor turned ON, the motor rotates forward.

When a reverse rotation signal to _"1", and _{Q 8, Q 3, Q 4} , Q 5 is ON, joined by positive voltage to one side of the motor, the motor is reversed.

When a voltage is applied to the motor and the motor is rotating, a current flows through R ₆ . The voltage of R ₆ at this time is amplified by the non-inverting amplifier and input to the + terminal of the comparator (IC1). When the motor is not energized, the voltage on R ₆ is OV and the voltage on the + terminal of the comparator is low. Therefore,
The lock signal is also "0".

The voltage of R ₆ rises when the motor is rotating due to the voltage applied to it, but the lock signal is “0” because it is below the threshold voltage of the comparator.

When the motor is energized and is not rotating, the current of the motor increases and the voltage of R ₆ also rises, so the threshold voltage of the comparator is exceeded and the lock signal becomes “1”. In this way, the cleaner moves,
This lock signal is output when stopped by a stopper.

FIG. 5 shows a RAM map and a 1/0 map.

The RAM map flag has six types of motor control flags (request, initial completion, forward rotation completion, reverse rotation completion, abnormality detection, and abnormality flags), and each flag is from the cleaner drive motor M ₁ of each charger to the motor. Up to M ₄ are assigned to each bit. In particular, the request flag and the abnormality flag are assigned to the non-volatile memory.
The control flag includes a switching flag for switching the operation mode and a rising flag for detecting the rising of the manual switch.

The counter is 2 bytes for the number of copies, 2 bytes for CCHG1 for cleaner control, CCHG
There is 1 byte of TM. Particularly, the number counter is allocated as a non-volatile memory because it needs to be stored even when the power of the copying machine is turned off. (In the case of this embodiment,
Since the RAM is backed up by the battery, the area that is not cleared when the power is turned on is called a non-volatile memory. The area that is cleared when the power is turned on is a volatile memory. ) 1/0 map The input signal includes a lock signal (for each motor), and the switch signals include switching SW ₁ and SW ₂ reset SW. Since the signal of the fixing thermistor is input through the A / D converter, it enters the computer side as 8-bit data. There is also an input signal for the manual switch.

The output signals include forward / reverse rotation signals of each motor. Also, there is an output of an abnormality display.

The operation of the control mechanism configured as above will be described.

When the power of the copying machine is turned on, the microcomputer starts executing the program. When the main execution of the charger cleaner control program starts, the charger cleaner control program is executed.

Next, the control program of the charger cleaner will be described with reference to the main flowchart shown in FIG.

First, the functions of the switches will be described.

Manual switch This is a switch that is manually operated by a service person. When this switch is turned on, each cleaner operates only once.

Changeover switch 1 When this switch is OFF, the main SW of the copying machine is turned on.
When set to N, each cleaner operates only once if the fixing temperature is below a certain temperature t ° C. Further, in this operation mode, when the temperature reaches t ° C. during one cycle operation of the cleaner, only the cleaner that is operating at that time completes the reverse rotation operation and stops, and does not move to the operation of the next cleaner. If the fixing temperature has already reached t ° C. when the power is turned on, the cleaner does not operate. When this switch is ON, the above OFF operation is not performed, but when the number of copies reaches, for example, 5000, it is operated for one cycle. Since the number of copies is stored in the non-volatile memory, the count value is not cleared even when the power is turned off. Then, the counter is cleared after the operation of one cycle is completed.

Changeover switch 2 When this switch is ON, the operation is a combination of the operation mode when the changeover SW1 is OFF and the operation mode when it is ON.

That is, one cycle operation is performed when the power is turned on (under the condition that the fixing temperature is t ° C. or less), and when the number of copies reaches 5000 sheets.

Next, the operation of the flowchart will be described.

First, it is checked whether the manual switch is ON. If it is OFF, the rising flag of the manual switch is set to 0, and then the ON check of the main motor is performed.

Although not shown, the main motor is a motor that drives a photoconductor drum of a copying machine, a conveyance roller, a belt, a roller, or the like. Therefore, this motor is turned on during operation during copying.
is doing. The reason why the main motor is ON is determined mainly because the cleaner is not operated during copying.

If the main motor is ON, the contents of the reverse rotation flag are put in the initial completion flag and the forward rotation completion flag as they are. This is so that when the main motor rotates when the initial or normal rotation is completed, the cleaner that has not completed the reverse rotation starts from the initial again. Therefore, those that have been completed up to reverse rotation remain unchanged, and those that have completed halfway have their initial completion and forward rotation completion flags cleared. Then, the request flag is set so that it becomes the next motor after the motor whose reverse rotation has been completed.
I'm getting an ET. As a result, at the time of the next operation, the motor next to the motor whose reverse rotation is completed is started by the initial operation.

Next, if the main motor is off, the door OPEN of the copying machine is checked. If the door is open, the contents of the reverse rotation completion flag are put in the initial completion / forward rotation completion flag and the request flag is set to the motor next to the motor that has completed the reverse rotation, as in the above-described operation. In this case as well, when the door is opened while the cleaner is operating, the operation performed halfway is canceled. In the case of a copying machine, when the door is opened, it is not in a working state from the viewpoint of safety.

Next, if the door is closed, the switch SW2 is checked. If it is OFF, the switching SW1 is checked. If it is OFF, the mode is one cycle operation when the power is ON. First, the number counter is set to 0,
Check the fixing temperature. The fixing temperature is a predetermined temperature t
If it is below ℃, each motor is cycled one cycle (M ₁ → M ₂
→ M ₃ → M ₄ ) only. This assumes a cleaner operation once a day. Therefore, in this case, the number counter is irrelevant. If the fixing temperature is equal to or higher than t ° C., it is checked whether or not the cleaner motor is turned on. If Yes, the cleaner control must be continued, so the cleaner control is performed. If No, it is checked whether the forward rotation flag and the reverse rotation flag are equal, and if they are equal, the switching flag is set to 1 and RET. If they are different, it indicates that the cleaner position is not the home position. Must be done. After this, the flow is for operating the cleaner for one cycle.

Next, the operation when the manual SW is turned on will be described. Manual S
If W is ON, it is checked whether or not the rising flag of the manual switch is 1, and since it is 0 at first, the M ₁ request flag is set to 1 and other flags (initial completion flag, forward rotation completion flag, reverse rotation completion flag) are set to 0, and RET is set. To do. Next time the main is executed, since the rising flag is set to 1, the flow moves to the flow for operating the cleaner for one cycle.

Next, the operation when the switch SW1 is turned on will be described. If the changeover switch SW2 is OFF and the changeover switch SW1 is ON, the mode is activated depending on the number of copies. First, it is checked whether the number counter is 5000 or more. M ₂ if
The request flag is set to 1, the other flags (see above) are set to 0, and RET is performed. If the number of copies is 5,000 or more, move to the flow of operating the cleaner for one cycle.

Next, the operation when the switch SW2 is turned on will be described. Switching S
When W2 is ON, it is checked whether the switching flag is 1, and since it is 0 at first, the process goes to No, and the operation flow when the power is ON is performed. If the fixing temperature is t ° C. or lower, the switching flag is set to 1 after the cleaning operation for one cycle is completed. After that, since the switching flag is 1, the mode shifts to the mode that operates depending on the number of copies.

Next, the flow of operating the cleaner for one cycle will be described.

First, the request flag is checked.

When all the request flags are 0 (the memory content is 0 at the beginning), the request flag of M1 is set to 1.
If any of the request flags is set to 1, the above process is skipped and the initial completion flag is checked. This is an initial completion check for a motor whose request flag is 1. Below, check the forward rotation complete flag and the reverse rotation complete check:
This is a check for a motor whose request flag is 1.

If the initial completion flag is 0, go to the initial routine and RET. If the initial completion flag is 1 and the forward rotation flag is 0, the routine goes to the forward rotation routine and RET is performed.

If the initial completion flag is 1, the forward rotation completion flag is 1 and the reverse rotation flag is 0, the routine goes to the reverse rotation routine and RET is performed. If the reverse rotation flag is 1, check the reverse rotation flags of all the motors.
To do. If not, just RET.

In this way, one cycle of one charger motor cleaning operation is completed. That is, initial (operation to reverse the motor to return the cleaner to the home position) → forward rotation (operation to rotate the motor in the forward direction to move the cleaner in the direction opposite to the home position) → reverse rotation (reverse the motor to the home position) The operation of returning the cleaner in the opposite direction to the home position) is one cycle.

Next, the case where the changeover switch is ON will be described. This is a mode in which the operation of the cleaner is controlled by the total number of copies. At this time, if the number of sheets is 5000 or more, the operation of the cleaner is started. If not, the request flag of M ₁ is set to 1 and all initial completion / normal rotation / completion / reverse rotation completion flags are set. To 0 and RE
T.

The operation when the number of sheets counter reaches 5000 or more is shown below.

Then, the number counter is set to 0.

[Effects] The charge wire or the shield member is not rapidly soiled by using a copying machine, and the soiling is easier to remove if it is frequently cleaned before it becomes severe. Therefore, it suffices to clean the charge wire or the shield member once a day, and if it is carried out more than that, power is wasted. Also, excessive cleaning of the wire can reduce the life of the wire.

However, according to the present invention, since the cleaning is automatically performed when the image forming apparatus main body is turned on, the cleaning is guaranteed to be performed once a day, and further, when the fixing temperature is lower than the predetermined value. By doing so, it is possible to prevent unnecessary cleaning when the power is turned off to save electricity, or when the power is turned on again after the power is turned off during inspection, and also when the heat fixing unit is in the copy ready state. Therefore, the lost time can be prevented.

Further, in an image forming apparatus that sequentially cleans a plurality of chargers, if the fixing temperature is lowered when the power is turned on, the cleaning of the charger is started. Therefore, the cleaning is finished even if the fixing temperature rises during the cleaning. According to the present invention, if the fixing temperature exceeds a predetermined value during the cleaning of the wire or the shield member, after the completion of cleaning of the charger during cleaning, the operator of the next Since the cleaning is not performed, the above problems can be prevented.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a copying machine using the present invention, FIG. 2 is a top view of a charger cleaner device, FIG. 3 is a circuit diagram of the copying machine, FIG. 4 is a circuit diagram of a motor drive, and FIG. The figure shows R
AM map and 1/0 map, FIG. 6 is a main flow chart. 1 ... Photosensitive drum, 2 ... Charging charger, 18 ... Pre-transfer charger, 19 ... Separation charger, 20 ... Pre-cleaning charger, 21 ... Casing, 22 ... Charge wire, 26 ... Cleaning member ( Cleaner), 27 ... Motor.

Claims (1)

[Scope of utility model registration request] 1. A cleaning member for cleaning a charge wire or a shield member, means for abutting the cleaning member on the wire or shield member, and moving means for moving the abutting means along the wire or shield member. An image forming apparatus equipped with a plurality of chargers having a plurality of chargers, which operates the cleaning members of the plurality of chargers at different times to clean the wires or shield members of the plurality of chargers, detects the temperature of the fixing unit. And a means for activating the moving means when the detection means detects that the temperature is equal to or lower than a predetermined value when the image forming apparatus main body is powered on. If the fixing temperature reaches a specified value during cleaning, after cleaning the wire or shield member being cleaned, the next wire Or the image forming apparatus characterized by cleaning of the shield member and a control means for controlling not to perform.