JPH1090983A - Wire cleaner device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire cleaner capable of preventing the formation of abnormal images caused by locking of a cleaning means in the middle of a process, automatically releasing midway stop caused by slight stains of the cleaning means and preventing the formation of abnormal images, the occurrence of jamming or the deterioration of image forming work caused by the midway stop which is caused by the slight stains of the cleaning means. SOLUTION: A wire cleaner device is composed of, in a corona discharging device, a cleaning means 111 for cleaning a charge wire, a motor 112 for moving this cleaning means 111, an abnormality determining means 113 for determining the midway stop of the cleaning means 111 and a control means 114 for forcibly moving the cleaning means 111 by giving energy larger than usual to the motor 112 based on the determination of the cleaning means midway stop made by the abnormality determining means 113.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire cleaner for cleaning a charge wire of a corona discharge device in a copying machine, a facsimile, a printer, or the like.

[0002]

2. Description of the Related Art A corona discharge device causes unevenness in corona discharge due to contamination of a charge wire, and when used as a charging device in an image forming apparatus such as a copying machine, the unevenness of the corona discharge causes an image on the image due to uneven charging. White streaks occur, and when used as a transfer device in an image forming apparatus, image transfer loss (white spots) occurs due to unevenness of corona discharge. When used as a separation device in an image forming apparatus, There is a fear that recording paper separation failure may occur due to unevenness of corona discharge. Therefore, in order to prevent these problems in advance, a wire cleaner for cleaning the charge wire of the corona discharge device is currently used. In this wire cleaner, a cleaning means including a pad or the like is reciprocated by a motor, and the cleaning means cleans the charge wire in the corona discharge device. When the cleaning means moves from the home position at one end of the charge wire to the other end of the charge wire and stops at the stopper, an overcurrent flows through the motor, and when the cleaning means returns to the home position and stops. Overcurrent flows to the motor. Then, by detecting the overcurrent flowing through the motor, the cleaning unit moves from the home position to the other end of the charge wire, and detects that the cleaning unit moves from the other end of the charge wire to the home position. Is reversed or stopped, and one cleaning operation is completed by one reciprocating movement of the cleaning means.

[0003]

In the above-described wire cleaner, since the developing unit in the image forming apparatus uses ultra-fine particles called toner, the cleaning means becomes dirty with toner from the developing unit due to repeated use. The load increases.
Then, the toner may adhere to the charge wire due to the scattering of the toner from the developing unit, and the cleaning unit may stop halfway due to an increase in the load. In this case, the charge wire is disconnected due to heat generated by the motor. An abnormal image or jam occurs. Further, by detecting an overcurrent flowing to the motor, it is detected that the cleaning means has moved from the home position to the other end of the charge wire, and that the cleaning means has moved from the other end of the charge wire to the home position. Therefore, even if the cleaning means locks for some reason on the way between the home position and the other end of the charge wire, the cleaning means reaches the home position or the other end of the charge wire due to the overcurrent of the motor. If the cleaning means is locked in the middle between the home position and the other end of the charge wire, copying work or the like in a copying machine or the like is performed, and an abnormal image of white spots and white streaks is detected. I will come out. Therefore, if the cleaning means stops on the way, it is conceivable to detect it with a sensor and display an abnormal operation, stop the machine and display a serviceman's call, but this is due to cleaning with slight dirt. Even if the means is stopped halfway, the machine is stopped and the image forming operation cannot be performed until the repair by the service person is completed, so that the image forming operation of the image forming apparatus is deteriorated.

The present invention solves the above-mentioned drawbacks, can prevent the occurrence of an abnormal image due to the locking of the cleaning means halfway, and can automatically cancel the halfway stop of the cleaning means due to slight dirt. An object of the present invention is to provide a wire cleaner device capable of preventing occurrence of an abnormal image or a jam due to a slight stop of a cleaning unit due to a slight contamination and deterioration of an image forming operation of an image forming apparatus.

[0005]

Means for Solving the Problems To achieve the above object, the invention according to claim 1 is a cleaning means for cleaning a charge wire in a corona discharge device as shown in FIG.
11 and a motor 112 for moving the cleaning means 111
The abnormality determination means 113 for determining that the cleaning means 111 has stopped halfway, and the cleaning means 111 forcibly stops the cleaning means 111 by applying a larger energy to the motor 112 by the determination of the cleaning means halfway stop. And control means 114 for moving to

According to a second aspect of the present invention, as shown in FIG. 2, a cleaning means 121 for cleaning while moving a charge wire in a corona discharge device, a motor 122 for moving the cleaning means 121, and a motor 122 An overcurrent detecting means 123 for detecting a flowing overcurrent, a home sensor 124 for detecting the cleaning means 121 at a home position on one end side of the charge wire, and an overcurrent detecting means 12
An abnormality judging means 125 for judging an abnormality in the movement of the cleaning means 121 using the detection signal of No. 3 and the detection signal of the home sensor 124. And vibration generating means 126 for applying vibration.

According to a third aspect of the present invention, as shown in FIG. 3, the cleaning means 131 for cleaning the corona discharge device while moving the charge wire, the motor 132 for moving the cleaning means 131, and the cleaning means 131 An abnormality determining means 133 for determining that the cleaning means 131 has stopped halfway, and a vibration generating means 134 for applying vibration to the cleaning means 131 based on the cleaning means halfway stop determination of the abnormality determining means 133.

[0008]

FIG. 5 to FIG. 10 show a mechanism in an embodiment of the present invention. This embodiment is for charging (or may be for transfer or static elimination) in a copying machine.
It is built into a corona discharge device. The corona discharge device includes end blocks 1 at both ends of the pair of side plates 11 and 12.
3 and 14 are integrally fixed and a back plate 15 is fixed above the side plates 11 and 12 to form a shield case. In the shield case, two charge wires 16 and 17 are arranged in parallel and both ends thereof are arranged. Are fixed to the end blocks 13 and 14. This corona discharge device is arranged such that an opening 19 on the lower side of a shield case is opposed to a photoreceptor 18 in a copying machine or the like, and charge wires 16 and 17 perform corona discharge by applying a high voltage by a drive circuit and move. The photoconductor 18 inside is uniformly charged. A partition 20 is formed between the end blocks 13 and 14 and the opening 19 in the shield case.

The mechanism of the wire cleaner device is incorporated in the corona discharge device, and the back plate 15 in the shield case is provided.
A motor 21 and a pulley 22 are attached to one end of the pulley 2.
2 are connected. Another end is attached to the other end of the back plate 15.
Pulley 24 is attached, and wire 25 is connected to pulley 2
2, 24, and the hook portions 27, 2 of the cleaning means 26
8 is fixed. Further, a pair of rails 29 and 30 are attached to the back plate 15 in parallel with the charge wires 16 and 17, and the cleaning means 26 is guided by the rails 29 and 30 to reciprocate. The cleaning means 26 includes a support table 31 engaged with the rails 29 and 30 and four feet 32 to 35 planted on the support table 31. The cleaning pads 36 to 39 are arranged on the charge wires 16 and 17 side.
Has been fixed. The cleaning means 26 is stored at a home position outside the charged area (opening 19) when not in use. In this home position, the cleaning means 26 is kept in an upright state without being inclined in contact with the cut wall portion 20 and the cleaning pad is provided. 36 ~
39 is not in contact with the charge wires 16 and 17. When the motor 21 is energized to rotate the pulley 22 via the worm gear mechanism 23, the wire 25 is driven to move the cleaning means 26 from the home position to the charge wires 16,1.
7 to the other end. As a result, the cleaning means 26 moves along the rails 29 and 30 in an inclined state. When the cleaning means 26 reaches the other end of the charge wires 16 and 17 and hits the end block 14, the motor 21 rotates in the reverse direction, and the cleaning means 26 cleans the charge wires 16 and 17 while returning to the home position. At this time, the cleaning means 26 is tilted in the opposite direction to the forward movement, and the cleaning pad 36
３９39 all rub against the charge wires 16 and 17 to clean them. When the cleaning means 26 reaches the home position, the motor 21 stops and the charge wire 16,
Cleaning of 17 is completed.

The sensor 41 is attached to one end of the shield case, and detects the cleaning means 26 at its home position. When the cleaning means 26 reaches the home position on the other end side of the charge wires 16 and 17 and hits the end block 14, the cleaning means 26 is detected by the sensor 42 attached to the shield case.

FIG. 4 shows a circuit section of this embodiment. In the figure, reference numeral 83 denotes a cleaning means control CPU (microcomputer) as control means; 85, a motor drive section for driving the motor 21; 86, a current detection section for detecting a current flowing through the motor 21; A position detection unit 88 for detecting whether the cleaning means 26 is at the home position based on the detection signal, and a main CPU 88 for controlling the main body of the copying machine.

FIG. 11 shows a part of the processing flow of the CPU 83 and the processing flow of the main CPU 88. In this embodiment, when a specific condition is reached in the copying machine, the cleaning means control CPU 83 is operated by a signal output from the main CPU 88. In a state where the copying machine is not performing a copying operation, the cleaning unit 26 is always waiting at a home position detected by one of the sensors 41 and 42.
If neither of the sensors 41 and 42 can detect the cleaning means 26, it is determined that the cleaning means 26 has stopped halfway, and the operation is performed according to the flowchart of FIG. That is, when a signal is input from the main CPU 88 to the cleaning means control CPU 83 after the main switch of the copier is turned on, the cleaning means control CPU 83 first clears the counter n, and applies a voltage to the motor 21 to the motor drive unit 85. Let it. Therefore, the motor 21 moves the cleaning means 26 from the home position to clean the charge wires 16 and 17. The CPU 83 determines whether or not the cleaning unit 26 is at the home position about 2 seconds after the voltage is applied to the motor 21 (after the cleaning unit 26 has reached the stable operation area).
When the cleaning unit 26 is not at the home position, it is determined whether or not an overcurrent is flowing to the motor 21 from the output signal of the current detection unit 86 if the cleaning unit 26 is not at the home position. It is determined whether or not the cleaning means 26 is locked on the way. If no overcurrent is flowing through the motor 21, the CPU 83 causes the motor drive unit 85 to continuously apply the same voltage to the motor 21. If the initially set voltage is applied to the motor 21 as it is, the motor 21 is driven until the cleaning means 26 is detected by one of the sensors 41 and 42, and the cleaning means 26 reaches the home position and either Is detected by the sensor of C
The PU 83 checks the counter n, and since the counter n is 0, the motor driving unit 85 stops driving the motor 21 to stop the cleaning unit 26 at the home position.

If the initial voltage is not applied to the motor 21 until the cleaning means 26 reaches the home position,
That is, if an overcurrent flows to the motor 21 before the cleaning means 26 reaches the home position, the CPU 83 checks that the counter n is 0, assuming that the motor 21 is locked in the middle, and since this is 0, the motor driving unit 85 A large energy is given to the motor 21 by increasing the drive voltage of the motor 21 by 1.2 times. As a result, most of the minor locks of the cleaning means 26 are released.

The large energy applied to the motor 21 is set in eight steps. The CPU 83 checks at every two second intervals whether the cleaning means 26 is at the home position and checks whether an overcurrent is flowing through the motor 21. If the cleaning means 26 is not at the home position and an overcurrent is flowing through the motor 21 while checking whether or not the motor 21 is in the home position, the driving voltage of the motor 21 is increased by one step by the motor driving unit 85 and the counter n is counted up. Go. Thus, the CPU 8
Reference numeral 3 denotes an abnormality determining unit that determines that the cleaning unit 26 has stopped halfway. In this case, the upper limit of the drive voltage of the motor 21 is 1.6 times the normal voltage. This is the motor 21
To release the lock with as light a load as possible.
The overcurrent of the motor 21 is set in each step, and when the current detection unit 86 detects a current of about twice or more of the normal current in each step, the CPU 83 determines that the current is an overcurrent. For example, the overcurrent of each step is set to the following value or more.

[0015]

[Table 1]

If the cleaning means 26 operates before the drive voltage of the motor 21 reaches the upper limit drive voltage, the drive voltage of the motor 21 remains unchanged and the cleaning means 26 continues to operate. At the time point when either of the sensors 41 and 42 detects the value, the CPU 83 sets the counter n
Is checked, and since this is not 0, the drive voltage of the motor 21 is returned to the initially set voltage by the motor drive unit 85, and then the motor is stopped and a signal is sent to the main CPU 83 to enable copying. However, if the cleaning unit 26 stops again before reaching the home position, the CPU 83 causes the motor drive unit 85 to step up the current drive voltage of the motor 21 by one more step, and applies more excessive energy to the motor 21. When the cleaning means 26 operates again, the operation is the same as described above. However, also at this time, the upper limit of the drive voltage of the motor 21 is set to 1.6 times the normal voltage.

The driving voltage of the motor 21 is set to 1.6 of the normal voltage.
If the cleaning means 26 does not operate even if it is doubled, the motor 21 may generate heat.
Turns off the motor 21 by causing the motor drive unit 85 to return the drive voltage of the motor 21 to the initially set voltage.
An abnormal signal is sent to 88. The main CPU 88 causes the display unit to display a serviceman call according to the abnormal signal,
The copy operation is disabled in the copy disabled mode.

According to this embodiment, when the cleaning means is locked, the cleaning means is forcibly moved by applying a larger energy than usual to the motor, so that the cleaning means can be automatically released from being stopped halfway due to slight dirt. It is possible to prevent the occurrence of an abnormal image or a jam due to the stoppage of the cleaning unit due to a slight dirt, and to prevent the image forming apparatus from deteriorating the image forming operation.

FIG. 12 shows a part of the embodiment according to the second and third aspects of the invention, and the same parts as those in FIG. 5 are denoted by the same reference numerals. In this embodiment, the home sensor 4
1 is provided, but the sensor 42 is not provided. Further, the position detecting section 87 is omitted, and the cleaning means control C
A PU 83 that performs the processing shown in FIG. 13 is used as the PU.

First, during normal operation, the cleaning means control C
The PU 83a causes the motor driving unit 85 to rotate the motor 21 clockwise to move the cleaning unit 26 from the home position, and sets 1 to a counter n as shown in FIG. Then, the CPU 83a increments the counter n in step A, and causes the motor drive unit 85 to rotate the motor 21 clockwise for 2 seconds. Next, the CPU 83a takes in the average current value of the motor 21 detected by the current detection section 86, and determines whether or not this current value is a normal value in step B. In this case CP
The U83a determines that the average current value of the motor 21 is abnormal if the average current value is 60 mA or more, and that the average current value is normal if the average current value is 60 mA or less. Therefore, the CPU 83a constitutes an overcurrent detecting means for detecting an overcurrent flowing through the motor 21. During normal operation, the average current value of the motor 21 is 30 mA, and the CPU 83a determines in step M that K =
2 and the motor driving unit 85
The rotation of 1 is continued for 30 seconds. Next, the CPU 83a takes in the average current value of the motor 21 detected by the current detection unit 86 in step D, and determines in step E whether or not this current value is a normal value. If the average current value of the motor 21 is a normal value, the CPU 83a sets the current detection unit 86 every 3 seconds.
The retrieving of the average current value of the motor 21 detected in step (1) and the determination of whether the current value is a normal value are repeatedly performed. When the cleaning means 26 reaches the ends of the charge wires 16 and 17 and a current greater than a normal value flows through the motor 21, the CPU 8
3a is step F, 25 seconds from the start of rotation of the motor 21.
It is determined whether or not c has elapsed. That is, CPU
83a constitutes abnormality determination means for determining a movement abnormality of the cleaning means 26 using the detection signal of the overcurrent detection means (overcurrent detection result) and the detection signal of the home sensor 41. Here, the cleaning means 26 is moved for 25 seconds both in the forward movement and in the backward movement.
If so, the entire area of the charge wires 16 and 17 can be moved. During normal operation, 25 seconds or more have elapsed since the start of rotation of the motor 21, the CPU 83a determines in step G whether K is 3 or not. Then, since K is 2, the CPU 83a sets K = 3, and in step H, causes the motor driving unit 85 to rotate the motor 21 counterclockwise for 30 seconds to move the cleaning unit 26 back. Then, the CPU 83
a returns to step D, and repeats taking in the average current value of the motor 21 detected by the current detection unit 86 every 3 seconds and determining whether or not this current value is a normal value. Thereafter, the cleaning means 26 returns to the home position and the motor 2
When a current equal to or greater than the normal value flows through the CPU 1, the CPU 83a determines in step F whether or not 25 seconds have elapsed since the start of rotation of the motor 21. Since 25 seconds or more have elapsed since the start of the left rotation of the motor 21 during normal operation, the CPU 83a determines in step G whether K is 3 or not. Then, since K is 3, the CPU 83a checks the signal from the home sensor 41 in step L to determine whether or not the cleaning unit 26 is at the home position. If the cleaning unit 26 is at the home position, the process ends. I do.

When the movement of the cleaning means 26 is not normal, for example, when the motor 21 is rotated clockwise for 2 seconds, the cleaning means 26 is locked to the charge wires 16 and 17 and the current of the motor 21 is determined to be normal in step B. When it is determined that the value is equal to or more than the value, the CPU 83a increments the counter n in
1 is rotated left by 2 seconds. Then, the CPU 83a takes in the average current value of the motor 21 detected by the current detection section 86, and determines whether or not this current value is a normal value in step J. If the average current value of the motor 21 is not a normal value, the CPU 83a proceeds to step A if the counter n is 10 or less.
Therefore, the motor 21 alternately repeats clockwise rotation and counterclockwise rotation every 2 seconds to apply vibration to the cleaning means 26. Therefore, the CPU 83a constitutes a vibration generating unit that applies vibration to the cleaning unit 26 based on the abnormality (lock of the cleaning unit 26) determined by the abnormality determining unit. If the average current value of the motor 21 does not reach a normal value even if the counter n reaches 10, the CPU 83a turns on a display unit (not shown) to perform a serviceman call, and stops the machine. When the average current value of the motor 21 becomes a normal value due to the unlocking of the cleaning unit 26 due to the vibration,
For example, when the motor 21 is rotating clockwise, the CPU 83a proceeds from step B to step M to return to the normal driving operation of the motor 21. When the motor 21 is rotating counterclockwise, the CPU 83a sets K = 1 from step J. After that, the process proceeds to step C to return to the normal driving operation of the motor 21.

The cleaning means 26 is provided with the charge wire 16,
17 and when it is determined in step F that 25 seconds or more have not elapsed since the start of rotation of the motor 21, the CPU 83a checks whether K is 2 (whether the motor 21 is being driven to rotate right). , K = 2, the process proceeds to step I, and if K = 2, the process proceeds to step A to cause the motor 21 to alternately rotate clockwise and counterclockwise every 2 seconds to apply vibration to the cleaning means 26 as described above. If it is determined in step L that the cleaning means 26 is not at the home position, the process proceeds to step H.

According to this embodiment, when the cleaning means is locked, vibration is applied to the cleaning means, so that the intermediate stop of the cleaning means due to minor dirt can be automatically released, and the cleaning means can be stopped halfway due to minor dirt. It is possible to prevent occurrence of an abnormal image or a jam and deterioration of an image forming operation of the image forming apparatus.

[0024]

As described above, according to the first aspect of the present invention, the cleaning means for cleaning the charge wire in the corona discharge device, the motor for moving the cleaning means, and the fact that the cleaning means has stopped halfway. The cleaning means is provided with an abnormality judging means for judging and a control means for giving a larger energy than usual to the motor and forcibly moving the cleaning means by the judgment of the cleaning means halfway stop by the abnormality judging means. It is possible to prevent the occurrence of abnormal images caused by locking with the device, and to automatically cancel the halfway stop of the cleaning means due to slight dirt. It is possible to prevent the jam and the deterioration of the image forming operation of the image forming apparatus.

According to the second aspect of the present invention, a cleaning means for cleaning the corona discharge device while moving the charge wire, a motor for moving the cleaning means, and an overcurrent detecting means for detecting an overcurrent flowing through the motor. A home sensor that detects the cleaning unit at a home position on one end side of the charge wire; and an abnormality that determines a movement abnormality of the cleaning unit using a detection signal of the overcurrent detection unit and a detection signal of the home sensor. Since the determination unit and the vibration generation unit that applies vibration to the cleaning unit based on the cleaning unit movement abnormality determination of the abnormality determination unit are provided, it is possible to prevent the occurrence of an abnormal image due to the locking of the cleaning unit halfway. In addition, the stoppage of the cleaning means due to slight dirt can be automatically released, and the stoppage of the cleaning means due to slight dirt can cause an abnormal image or jam. It is possible to prevent the deterioration of the image forming operation of the fine image forming apparatus occurs.

According to the third aspect of the present invention, a cleaning means for cleaning the corona discharge device while moving the charge wire, a motor for moving the cleaning means, and an abnormality for judging that the cleaning means has stopped halfway. Determining means;
A vibration generating means for applying vibration to the cleaning means by the cleaning means halfway stop determination of the abnormality determining means, so that it is possible to prevent the occurrence of an abnormal image due to the locking of the cleaning means on the way, and The intermediate stop due to slight dirt can be automatically canceled, and it is possible to prevent the abnormal stop, the jam, and the deterioration of the image forming operation of the image forming apparatus caused by the partial stop of the cleaning unit due to slight dirt.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the invention according to claim 1;

FIG. 2 is a block diagram showing the invention according to claim 2;

FIG. 3 is a block diagram showing the invention according to claim 3;

FIG. 4 is a circuit diagram showing a circuit section of one embodiment of the invention according to claim 1;

FIG. 5 is an explanatory diagram of the embodiment.

FIG. 6 is a schematic side view showing a part of the embodiment.

FIG. 7 is a sectional view taken along line II-II of FIG.

FIG. 8 is a perspective view showing one end of the back plate side of the embodiment.

FIG. 9 is a perspective view showing a part of the end block side of the embodiment.

FIG. 10 is a perspective view showing the other end of the back plate side of the embodiment.

FIG. 11 is a flowchart showing a processing flow of a CPU in the embodiment.

FIG. 12 is an explanatory view of an embodiment of the invention according to claims 2 and 3;

FIG. 13 is a flowchart showing a processing flow of a CPU in the embodiment. 111, 121, 131 Cleaning means 112, 122, 132 Motor 113 Abnormality determination means 114 Control means 123 Overcurrent detection means 124 Home sensor 125 Abnormality determination means 133 Abnormality determination means 126, 134 Vibration generation means

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Tetsuya Fujioka 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd.

Claims (3)

[Claims] 1. A cleaning means for cleaning a charge wire in a corona discharge device, a motor for moving the cleaning means, an abnormality determining means for determining that the cleaning means has stopped halfway, and a cleaning means for the abnormality determining means. A control unit for applying a larger energy than usual to the motor based on the halfway stop determination and forcibly moving the cleaning unit. 2. A cleaning means for cleaning a corona discharge device while moving a charge wire, a motor for moving the cleaning means, an overcurrent detection means for detecting an overcurrent flowing through the motor, and one end of the charge wire. A home sensor for detecting the cleaning unit at the home position on the side, an abnormality determination unit for determining a movement abnormality of the cleaning unit using a detection signal of the overcurrent detection unit and a detection signal of the home sensor, and determining the abnormality. And a vibration generating means for applying vibration to the cleaning means when the cleaning means moves abnormally. 3. A cleaning means for cleaning a corona discharge device while moving a charge wire, a motor for moving the cleaning means, an abnormality judging means for judging that the cleaning means has stopped halfway, and this abnormality judging means. And a vibration generating means for applying vibration to the cleaning means based on the determination of the cleaning means halfway stop.