JP3208616B2 - Charging device for image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Object of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electrostatic transfer process, such as an electrostatic copying machine and a printer, and more particularly to a charging device for the image forming apparatus.

[0002]

In a known image forming apparatus as described above, when an electrostatic latent image is formed on an image carrier, a toner image formed on the image carrier is transferred to a transfer material such as paper. In such a case, it is necessary to use a charging unit in order to apply a charge to the surface of the image carrier, the surface of the transfer material, or the like, which is to be charged.

The charging means used for this purpose includes:
Conventionally, a corona discharge device in which a charging wire is stretched in a shield case opened to the charged surface side and a bias voltage is applied thereto has been widely used.

However, in this type of image forming apparatus, the toner used for forming a toner image is fine particles of the order of microns, and it is difficult to perform the development and transfer steps while maintaining a sealed state. And fine paper powder generated from paper that is frequently used as a transfer material,
Various foreign substances such as rosin, talc, and other deposits, dust, and the like are present in a floating state in the image forming apparatus, and adhere to a charging wire to cause charging unevenness and charging failure.
The possibility of deterioration of image quality due to this was inevitable.

In order to cope with such a problem, a cleaning member provided with a member for sandwiching the charging wire is moved along the charging wire by driving means disposed near the charger, and the cleaning member is rubbed and cleaned. Have already been proposed. By the way, since this type of charger is usually treated as a consumable,
The charger including the cleaning member and the driving means for driving the cleaning member are formed separately, and only the charger including the cleaning member is detachably configured. Hereinafter, such a thing will be described.

FIG. 25 is a side view schematically showing the configuration of a known image forming apparatus, in which a cylindrical image carrier 12 having an axis perpendicular to the paper surface rotates and runs in the direction of the arrow shown in FIG.
The surface photosensitive layer is uniformly charged by the primary charger 1, and an image signal L is applied to the charged surface to form an electrostatic latent image. When the latent image reaches a developing site where the developing device 14 is disposed, toner is supplied from the developing device, and the latent image is visualized to become a toner image. Furthermore, this toner image
When the transfer material arrives at the transfer site where the transfer charger is disposed, a transfer material (not shown) is supplied to the transfer site from the transport path 17, and at the same time, a transfer bias is applied to the transfer charger 15 so that the toner image on the image carrier side is Is transferred to the transfer material. Thereafter, the transfer material is separated from the image carrier 12 and is conveyed to a fixing portion (not shown) via the conveyance path 18.

FIG. 26 is a perspective view of the image forming apparatus as described above, in which the image carrier and the transfer charger at the transfer portion are removed and only the driving section of the cleaning member is shown. It has a rail member 28 fixed to the upstream side of the path 18 and having a slit 28c extending in the longitudinal direction at the bottom. A screw 29 is provided below the rail member 28.
b is disposed and the worm gear 29 provided at the end thereof
A worm 29e provided on the output shaft of a motor 29d that can rotate forward and reverse is engaged with c.

Although not shown, a drive block is engaged with the screw 29b, and the screw 29b moves in either the left or right direction with the rotation of the motor. A rotatable engaging claw 129h, which is biased clockwise (as viewed from above) by a spring 31, is pivotally attached to a portion of the drive block projecting upward from the slit 28c.

When the charger 15 is mounted, the charger 15 is disposed in parallel above the above-mentioned driving unit. At this time, an engaging rod body protruding from the cleaning member provided on the charger to the outside of the bottom surface of the shield case. (described below), by rotating the engaging pawl 129h against the resilience of the spring 31 engages the engaging rod in the recess 129h ₁ engaging claws 129h. Therefore, by driving the motor thereafter, the drive block,
The cleaning member can be moved along the charging wire via the engaging claw 129h and the rod, and can be rubbed and cleaned. Reference numerals 29g and 29f are microswitches for detecting the position of the drive unit.

[0010] "Figure 27a" through "Figure 27c" is the above-described mechanism, the relationship between the rod protruding downward of the cleaning member side with engaging claws 129h charger (in the figure is indicated by reference numeral 126a ₂₎ It shows. In the configuration of the drive unit as shown in FIG. 26, when the charger is inserted from the lower left in the figure, the rod 12 protruding downward from the charger side.
Although 6a ₂ comes into contact with the claw portion 129h ₂ engaging claws 129h side, the insertion speed of this time the charger is too fast, the engaging claw 1
As a result, as shown in FIGS. 27B and 27C, the rod body exceeds the engaging claw 129h, and thereafter, the rod body, and thus the cleaning member, are moved. There is a possibility that a situation may occur in which it cannot be moved.

Further, as shown in FIG.
Since there is a play G between the rail members 28 on which the driving unit (indicated by the reference numeral 133) supporting the driving unit 29h is guided, as shown in the drawing, the driving unit moves leftward as shown in FIG.
Inevitably possibility of engaging the occurrence of situation in which no floor well with the rod 126a ₂ of 29h and the charger side is generated. Further, when the cleaning member reaches a predetermined end position,
In order to detect this, it is necessary to dispose detection means such as a microswitch at both ends of the stroke of the cleaning member, which requires a correspondingly large space and is disadvantageous in cost.

The present invention has been made in order to cope with such a situation, and has a charging device provided with a driving means having an engaging claw removably engaging with the cleaning member on the charger side as described above. When the cleaning member is moved in any direction, the engaging member on the driving section side is engaged with the driving member, so that it is impossible to travel in one direction as described above. It is an object of the present invention to provide a charging device which can reliably prevent the movement of the cleaning member and does not require any special means for detecting the moving end of the cleaning member.

In order to achieve the above object, the present invention is directed to a charging device guide portion provided on an image forming apparatus main body side, a driving portion provided therein, and a charging device detachably mounted on the guide portion. A cleaning member provided on the container and slidably rubbing the charging wire driven by the driving unit, wherein the engaging member provided on the cleaning member is engaged with the engaging member on the driving unit side. A driving unit for driving the cleaning member, wherein the engaging member on the driving unit can be engaged with the engaging member on the cleaning member in any of the traveling directions. A charging device (1) for an image forming apparatus, wherein an engaging member on the cleaning driving member side is securely engaged with an engaging member on the driving unit side during one reciprocation of the driving unit. , Sifting the above (1),
The charging device (2) of the image forming apparatus, wherein the engaging member on the cleaning member side has play at the engaging portion with respect to the engaging member on the driving unit side, or (1) or ( 2) In the control of (2), when the charging device is guided along the guiding portion, the control of the movement of the driving portion is performed such that the side opposite to the entrance side is at a stop position during reciprocation of the driving portion. A charging device (3) for an image forming apparatus, comprising: In any one of the above (1) to (3), at least one of the wall surfaces of the guide portion parallel to the traveling direction of the drive unit guides the drive unit, and the charging of the image forming apparatus is performed. Device (4).

With this configuration, the cleaning member provided on the charger can be reliably held and cleaned by the drive unit disposed on the main body side, and the space for the charging device can be saved and the cost can be reduced. Also contributes to down.

[0015]

FIG. 1 is an end view showing the structure of a transfer portion of an image forming apparatus as shown in FIG. 25 described above. A rail member 28 is disposed in the vicinity of the cylindrical image carrier 12 extending in a direction perpendicular to the plane of the paper, in parallel with the image carrier, and a charger 15 having a shield case 27 at an inner position thereof.
Is arranged.

In the illustrated case, three charging wires 25 are disposed in the shield case 27, and each charging wire 25 is sandwiched between pads, which will be described later, disposed on a movable cleaning member 26. It is arranged to be.

The cleaning member 26 is made equipped with suitable elasticity synthetic resin, the holder 26a and which is formed thereto and an arm 26a ₁ 3 pairs of the illustrated case. The holder 26a engages with a slit 28c formed in the longitudinal direction of the bottom of the shield case 27 so as to be slidable in that direction, that is, in the direction perpendicular to the paper surface. The arm 2
6a ₁ is Yes formed in two split has a length that its free end reaches the charging wire, felt inside, by arranging the pads 26b made of an elastic material such as sponge Atsute, these pads 26b sandwiches the charging wire 25. Further, from the bottom of the cleaning member 26, a rod 26a ₂
Are projected, and this engages with a lower drive unit described later.

FIG. 2 is a perspective view of a driving section showing an embodiment of the present invention. The basic configuration is as described in FIG.
6 ", corresponding portions are denoted by the same reference numerals, and a description thereof will be omitted unless necessary.

[0019] In this device, the elastic engaging and disengaging portion 29'H 2 is claw _29'H. Is Yes formed, by a spring 31, which is biased in a clockwise direction as viewed from illustrated above, the stopper portion 33a It shall be positioned. As shown in FIG. 3A, the stopper portion 33a
b, and this part is a bar 26a on the cleaning member side.
₂ is formed as a fixed wall.

As shown in FIGS. 3A to 3C,
Rod 26a ₂ of the cleaning member side is Kitasa has a portion that engages with the drive unit including the engagement claw 29'H ( "Figure 3c"), the further relative movement to the left in the figure, the rod body 26a ₂ There together to deform it engages the resilient disengaging portion 29'H ₂ of the engaging claw, said against the elasticity of the spring 31 by rotating the engaging pawl in a counterclockwise direction elastic engaging and disengaging (See “Fig. 3
b "), and then, as shown in FIG.
₂ comes into contact with the fixed wall 33b and thereafter travels rightward in the figure together with the drive unit.

The overall image of the cleaning operation may be the same as that shown in the flowchart shown in FIG.

In the case of this device, since the drive section side for locking the rod on the cleaning member side is formed in a fixed wall shape, the drive section side moves rapidly at the time of engagement, or the drive section moves to a predetermined position. Even if the charger is rapidly inserted in a case where the charging member is not provided, it is possible to prevent a situation in which the cleaning member passes through the driving unit before the engagement claw returns by the action of the spring 31. Also,
Since the stopper portion 33a is integrated with the fixed wall 33b, it is possible to avoid a situation in which the rod body passes through the engagement claw through the gap between the rail member 28 and the driving portion.

[0023] "Figure 4" is a side cross-sectional view showing another embodiment, the engaging portion of the said rod of the rod 226a ₂ and the drive unit 229 which were now projecting cleaning member 226 in FIG. 2
29h ₂ is shown. In this case, the engaging portion 22
9h ₂ is Yes so as to the rod and disengage moving in the vertical direction using the elasticity of the material serving as the synthetic resin itself, can save Yotsute horizontal space in such a configuration, returns Since a spring is unnecessary, it leads to cost reduction.

FIG. 5 shows another embodiment, which shows the configuration of a drive unit for driving the cleaning member of the charger. The basic configuration is the same as that shown in FIG. 26. engaging claw 2 rod body 26a ₂ projecting downward in the cleaning member side
The cleaning member 26 travels while holding the charging wire 25 by engaging with the charging wire 25.

Returning to FIG. 1, the charger 15 and the cleaning member 26 are detachably attached to the rail member 28. That is, guide portions 27c provided at the ends of the shield case 27 engage with side walls 28a formed on both sides in the longitudinal direction of the rail member 28, so that the shield case 27
Is attached to the rail member 28. At this time, the guide portion 2 is provided by a spring 28b disposed on the side wall 28.
7c is pressed upward and the charging wire 25 is
.

An engaging claw 29h disposed on the drive section 26 side is pivotally mounted on a drive block 29a screwed into the screw 29b, and is always clockwise (as viewed from above in FIG. 5).
To be biased by a spring 31 and is in contact with the stopper portion 33a, and a recess 29h ₁ disengaging rod 26a ₂ of the cleaning member, and the resilient disengaging member 29h _2. Further, as shown by reference numeral 29j in FIG. 6, the tip of the engaging claw is inclined so as to approach the pivot position.

[0027] The engagement claw 29h positional relationship between the rod body 26a _2, usually, as shown in "Figure 6", the engaging claw of the recess 2
9h1 is either located leftward of the rod body 26a _2, or, as shown in "Figure 7" is the one rod body 26a ₂ is located at the inclined portion of the elastic engaging and disengaging portion 29h ₂ engaging claws .

[0028] For the former, by the drive unit 26 is moved, "7" to the rod 26a ₁ abuts on the elastic engaging and disengaging portion 29h ₂ as, engagement disengaging portion of the elastic spring 31 acts Into the recess 29h ₁ against the engaging claw 29h
And welfare to the original position by the action of the spring 31, the rod body 26a ₁ is seated in the recess 29h _1, the drive unit and the cleaning member is operatively integrated ( "Figure 8").

As shown in FIG. 9, when the rod 26a is to the left of the engaging claw 29h, that is, outside the engaging claw 29h, the driving unit 26
Is moved to the left in the drawing, so that the rod 26a abuts on the tip inclined portion 29j of the engaging claw 29h, and then the engaging claw 29h is rotated counterclockwise in the drawing against the action of the spring 31 ( "Figure 10"), then the rod body enters the recess 29h ₁ engaging claws operatively integrating the cleaning member side and the driving unit ( "Figure 11"). Also, in order to pull out the charger from the driving portion side from the engaged state as shown in FIGS. 8 and 11, the elastic engaging / disengaging portion on the engaging claw side at the locking portion between the engaging claw and the rod body. By setting the shape of
It can be easily separated by pulling against its elasticity.

In short, the engaging claw 29h on the driving section side
Even taking a charger side of the rod body 26a ₂ and which of the related position, by moving the engaging claw 29h in either direction, so that it can transmit the motion of the drive unit to the cleaning member of the charging device securely connecting rod 26a ₂ claws 29h, the ready state. Further, when pulling out the charger from the image forming apparatus, "Figure 6c", by pulling from the engagement, such as "Figure 6f" the charger downward in the drawing, the rod body 26a ₂ is disengaged portion 29h ₂ Can be pulled out while being deflected against its elasticity.

The operation of the present apparatus will be described with reference to the flowchart shown in FIG. When power is turned on to the apparatus in step S1 in the figure, the process proceeds to step S2, where it is determined whether the microswitch on the standby position side is on or off. When it is ON, that is, when the drive block 29a is at the standby position of the rail member 28, the process proceeds to step 4 and the motor 29
Rotates forward. If the micro switch is off, the process proceeds to step S3 where the motor rotates in the reverse direction to drive the drive block 29a.
To the standby position.

When the drive motor rotates forward (step 4),
As a result, the screw 29b rotates and the drive block 29a travels from one end of the rail member 28 to the other end. This rod 26a ₂ of the cleaning member is disposed in the charger also moves along with the charging wire cleaning is done in this process.

Then, the process goes to step 5 to judge whether the micro switch on the opposite side is on or off. If it is on, the process moves to step 6 where the motor stops. If it is off, the motor returns to step 4 and the motor reverses.

After a lapse of a predetermined time after the motor is stopped, the motor starts to reversely rotate, and the drive block 29a, and thus the cleaning member 26, also travels in the opposite direction to the previous one to clean the charging wire. Reach the standby position. Then, the process goes to step 8 to turn on the micro switch on the standby side,
Judge off.

If it is ON, that is, if the drive block 29a has returned to the standby position, the routine proceeds to step 9, where the motor stops, and the cleaning operation ends. If it is off, the process returns to step 7 to continue the reverse rotation of the motor.

[0036] As described above, the drive side of the engaging claw 29h and rods 26a ₂ of the cleaning member side, it is made the relationship between the two positions and what state, either the engaging claw 29h The bar 26a ₂ on the cleaning member side
By connecting the forward and reverse rotation functions of the motor as described above, it is possible to reliably prevent the engagement claw and the rod from becoming locked, Even when stopped at the position, it returns once to the standby position and then reciprocates, so that the torsional torque is not generated in the screw and the cleaning operation can be always performed stably.

Further, even if the charger is suddenly inserted, the drive means to be engaged with the cleaning member is located at the back side as viewed from the insertion side, so that when the two are brought into contact with each other, no trouble is caused and trouble occurs. Can be prevented beforehand, and since the rod on the charger side and the engaging claw on the drive section engage after being inserted into the rail member for a long distance, the charger can be inserted obliquely by the rail member,
The rod of the cleaning member can be reliably guided to the engaging claw by preventing the inclination of the rod.

Further, when the drive unit moves rapidly at the time of engagement, or when the drive unit is not at a predetermined position, such as before moving the motor after assembling, the charger is suddenly inserted, so that the cleaning member is removed. Even if the rod body exceeds the drive unit, both are securely engaged as shown in FIGS. 6 to 11 during one reciprocation of the drive unit. I can do it.

Further, by rods 26a ₂ of the cleaning member side sets the size of both such that there is adequate clearance between the recess 29h ₁ of the engagement claw 29h, drives the motor In this case, the moving range is slightly smaller than the range that can be moved manually, and as shown in FIG.
It is possible to prevent the cleaning member from colliding with m and 27n to apply an excessive load to the motor.

In the above apparatus, two micro switches are used.
With only f, if the switch detects that the cleaning member is at the standby position at the start of cleaning and then performs cleaning, the same operation as described above can be achieved. Of course, an optical sensor or the like can be used instead of the microswitch. Further, as a driving unit of the driving unit, a driving unit may be attached to a belt, a wire, or the like instead of the screw, and reciprocated. In this case, since a belt and a pulley are used instead of the screw, the worm, and the worm gear, the configuration is simplified and the cost is advantageous.

The case where the present invention is applied to a transfer charger has been described above. However, it can be easily understood that the present invention can be applied to other chargers such as a primary charger.

FIG. 14 is a side sectional view of a main part showing another embodiment, and portions corresponding to those of the above-described apparatus are denoted by the same reference numerals.

In this apparatus, the cleaning member 2 of the charger is used.
Bar body 2 projecting downward from rail 26 in the direction of rail member 28
26a ₂ is adapted to engage with a vertically moving claw portion 229a ₂ provided on the drive portion 229 to compensate for a change in the relative positional relationship between the cleaning member side protrusion and the drive portion side claw portion. in order to form the other claw portion 229j as shown, securely during one reciprocation of the drive unit rod 226a ₂ it is enabled to capture. Other operations are the same as those of the above-described device.

According to such a configuration, the spring 31 in the above-mentioned device is not required, and only the elasticity of the synthetic resin itself as the constituent material can be used, and the space in the horizontal direction can be saved, which is advantageous in cost.

FIG. 15 shows a driving unit for driving the cleaning member of the charger cleaning means at the transfer site. Since they have substantially the same configuration and operation as those of the embodiments described above, they will be briefly described.

Reference numeral 18 denotes a transport path for transporting the transferred transfer material to the fixing portion, and a rail member 18 is disposed upstream of the transport path and below the image carrier (not shown).
A charger (not shown) is to be inserted and removed along this.

A slit 28c is provided in the bottom of the rail member 28 in the longitudinal direction, and a drive block (reference numeral 29a in FIG. 1) which is guided and slid by an edge of the slit 28c is provided below the rail member 28. And the screw 29b arranged at the bottom. A worm gear 29c is attached to an end of the screw 29b, and is engaged with a worm 29e provided on an output shaft of a forward / reverse rotatable motor 29d mounted at an appropriate position in the apparatus main body. Therefore, by driving the motor, the drive block 29a
It will travel along b.

Above the drive block 29a, an engaging claw 29h is pivotally supported inside the rail member, and the engaging claw 29h is provided with a cleaning member disposed in the charger. recess 29h ₁ to be engaged (sign 26a ₂ of "Figure 1") rod which extends to the rail member is formed,
It is further provided resilient disengaging portion 29h _2. Further, a spring 31 is locked to the engaging claw 29h, whereby the spring is constantly biased clockwise and positioned by the stopper portion 33a. Since the configuration of the above-described portions is shown in the above-mentioned "FIG. 1", the details are omitted.

FIGS. 16A to 16C are explanatory views showing the operation of the engaging claw 29h in the above-mentioned device. When the charger is inserted in the direction of the outlined arrow in the drawing, the rod on the cleaning member side is shown. 26a ₂ abuts on the elastic engaging / disengaging portion 29h ₂ of the engaging claw to rotate the engaging claw counterclockwise in the figure against the action of the spring 31, so that the rod moves beyond the elastic engaging / disengaging portion. Recess 29h ₁
After that, the rod body moves in the recess under the control of the driving unit, and the cleaning member connected to the rod body cleans the charging wire.

The control of the drive unit is performed as shown in the block diagram of FIG. 17, and the control means 30 is an R which stores the control contents of the entire image forming apparatus including the drive unit 29.
The OM 30b and an RA used as a work area for the CPU 30a and for temporarily storing various data.
M30c and an interface 30d. On the output side of the interface, there are a reading system (not shown) such as a reflection mirror, a primary charger 13, a developing unit 14, a transfer charger 15, a pickup roller for taking out a transfer material from a cassette, and transporting the transfer material to a transfer portion. Transport rollers (not shown), a transport path 18 and the like are connected.

As described above, when the charger is inserted into the image forming apparatus along the rail member 28, the engaging claws 29h are disposed on the charger as shown in FIGS. 16A to 16C. It engages the rod 26a ₂ of the cleaning member enters a standby state.

When a cleaning start signal is issued by the control system 30, the motor 29d is rotated forward in step S1 in the flowchart shown in FIG. 18 to rotate the screw 29b. This drive block 29a travels from one end to the other end of the rail member 28 is guided by the slit 28c, the cleaning member 26 by a connecting engagement claw 29h and the rod body 26a ₂ are sandwiching the charging wire 25 Cleaning Is performed.

Next, at step S2, a predetermined time t
₁ it is determined whether the elapsed reverses motor shifts to step S3 is time t ₁ after the lapse.

As a result, the cleaning member starts to move to the standby position while rubbing and cleaning the charging wire again.

[0055] then determines the elapsed time t ₂ in step S4, stops the motor shifts to step S5 after t ₂ elapses to end the cleaning.

In the above case, the relationship between the times t ₁ and t ₂ is represented by t
_{If 1} ≦ t ₂ is set, even if the cleaning member stops during the reciprocating operation due to some obstacle, the return time is longer, so that the cleaning member can be prevented from stopping in the middle of the image.

FIG. 19 shows another embodiment of the above control operation. Step S1 shown in FIG.
0, S11 are additional, after reversing the original motor in step S10, is adapted to determine the elapsed time shifts t ₀ to the step S11. Step S
By adding 11, it is possible to surely perform a series of cleaning operations after the driving unit and the cleaning member accompanying the driving unit are always drawn to the standby side of the rail member.

In this case, the time t ₀ is set to be slightly longer than the time required for the drive unit to move the rail member, so that the rotation of the motor is only stopped due to an overload such as a DC motor. This is convenient because the drive unit is located at the standby position after step S11 no matter where the drive unit is located.

FIG. 20 shows an embodiment in which a micro switch 29f for detecting the position of the drive unit is disposed at one end of the movement of the drive unit, and FIG. 20 shows the operation thereof. It is a flowchart.

In this chart, the times t ₀ , t ₁ , and t ₂ are all set slightly longer than the time during which the drive unit travels the stroke. Initially, the motor is reversed in step S21 to draw the drive unit to the standby position. At this time, step S
After the time t ₀ has elapsed of 22 not turned microswitch 29f is, when repeating the loop shown part (a) to step S30 assuming that problems such as the drive unit is stopped in the middle is occurring Then, the motor is stopped and an abnormality is displayed (step S31).

When the drive unit normally reaches the position of the microswitch 29f due to the reverse rotation of the motor, this turns on (step S23), and the motor starts normal rotation (step S2).
4) Yes. Hereinafter, steps S24 and S25 are “FIG. 18”.
Steps S1 and S2 are the same.

Steps S26 to S28 are the same as steps S21 to S13, and the motor is stopped after the charging wire is normally cleaned (step S29).

With this configuration, the stop of the drive unit can be detected and displayed, so that a failure or the like due to continued operation in an irregular state can be prevented.

FIG. 22 is a perspective view showing another embodiment. In this apparatus, the output of the motor 29d is transmitted to the drive section, except that a belt is used instead of a screw. There is no difference from each device.

As can be seen particularly from FIG. 23, below the rail member 28, one end is provided on a pulley 155 provided on the output shaft of the motor 29d, and the other end is provided on a pulley 156 provided on the opposite end of the rail member. Endless belt 151 suspended on
(Not limited to an endless belt), and a driving unit 2 for driving a cleaning member of a charger on the belt.
9 'is attached.

A disk 153 that rotates together with the output shaft of the motor 29d is attached to the opposite side of the output shaft. A large number of openings are formed in the disk in the circumferential direction as shown in FIG. 24, and as shown in FIG. 22, a photo interrupter is provided at a suitable position on the rail member or other immovable part. Yes,
Thus, the rotation angle of the motor can be detected.

[0067] Since in this manner are configured, since the amount of movement of the drive unit 29 'by the driving of the motor can be known by connexion to the rotation angle of the motor, the "13" in the time t _i in the flowchart below Instead, the movement of the driving unit is controlled by the rotation angle of the motor, and the cleaning of the charging wire can be similarly performed.

It is easy to understand that the same control can be performed by using a stepping motor instead of using the above-mentioned open disk, or by using a linear motor running on a rail member. By the way.

[0069]

As described above, according to the present invention, the image forming apparatus is provided with a cleaning member for holding the charging wire of the charging device and cleaning it by rubbing it. In a charging device including a driving unit that is driven in the extending direction to be engaged with and disengaged from the cleaning member and drives the cleaning member, even if a charger is rapidly mounted on the driving unit side or inserted in an irregular direction. It is possible to prevent a failure or a failure from occurring in the normal locking of the cleaning member on the charger side and the engaging / disengaging means on the driving section side, and to control the driving of the driving section based on time. Since the microswitch can be omitted, space saving and cost reduction are effective.

[Brief description of the drawings]

FIG. 1 is a sectional view of a charger and a driving unit of a charging device according to the present invention.

FIG. 2 is a perspective view of a main part of a driving unit showing an embodiment of the present invention.

FIG. 3 is an explanatory view showing a mode of engagement and disengagement of an engaging portion and a rod body of the device.

FIG. 4 is a sectional side view of a main part showing another embodiment.

FIG. 5 is a perspective view of a driving unit that drives a cleaning member of the charger.

FIG. 6 is an explanatory view showing an engagement and disengagement state of an engagement claw on a driving unit side and a rod on a cleaning member side.

FIG. 7 is an explanatory diagram showing another state of the above.

FIG. 8 is an explanatory view showing still another state of the above.

FIG. 9 is an explanatory view showing still another state of the above.

FIG. 10 is an explanatory view showing another state of the above.

FIG. 11 is an explanatory view showing still another state of the above.

FIG. 12 is a flowchart showing the operation of the charging device.

FIG. 13 is a plan view showing a movable range of the charger shield case and the cleaning member.

FIG. 14 is a sectional side view of a main part showing another configuration of the driving unit.

FIG. 15 is a perspective view of a drive unit showing still another embodiment.

FIG. 16 is an explanatory diagram showing a mode of engagement and disengagement between the engagement claw and the mother body

FIG. 17 is a block diagram of control means of the entire apparatus including a driving unit.

FIG. 18 is a block diagram showing the operation of the above device.

FIG. 19 is a flowchart showing another operation mode.

FIG. 20 is a perspective view of a drive unit showing still another embodiment.

FIG. 21 is a flowchart showing the operation of the above.

FIG. 22 is a perspective view of a drive unit showing still another embodiment.

FIG. 23 is a side sectional view of the essential part of the same.

FIG. 24 is a front view of a disk used in the above device.

FIG. 25 is a schematic side view of an image forming apparatus suitable for applying the present invention.

FIG. 26 is a perspective view of a drive unit for driving the cleaning member used in the above.

FIG. 27 is an explanatory view showing a mode of engagement and disengagement between the engaging claw and the rod according to the first embodiment;

FIG. 28 is a main part plan view showing the configuration of the engaging claw;

Claims (4)

(57) [Claims] An image forming apparatus includes: a charger guide disposed on a main body side of the image forming apparatus; a driver disposed on the charger guide; and a charger which is detachably mounted on the guide. A cleaning member for nipping and rubbing the driven charging wire; an engagement member provided on the cleaning member is engaged with the engagement member on the driving unit side to drive the cleaning member by the driving unit; In the charging device of the image forming apparatus, the engaging member on the driving unit side can engage with the engaging member on the cleaning member side in traveling in any direction, and during one reciprocation of the driving unit. A charging device for an image forming apparatus, wherein an engaging member on a cleaning drive member side is securely engaged with an engaging member on a driving unit side. 2. The charging device for an image forming apparatus according to claim 1, wherein the engaging member on the cleaning member side has a play at the engaging portion with respect to the engaging member on the driving unit side. . 3. A control means for controlling the movement of the driving unit so that the charging unit is guided along the guiding unit so that the opposite side of the charging unit to a stop position during reciprocation of the driving unit. 3. The charging device for an image forming apparatus according to claim 1, wherein the charging device comprises: 4. The driving device according to claim 1, wherein at least one of the wall surfaces of the guide portion parallel to the traveling direction of the driving portion guides the driving portion. Charging device for an image forming apparatus.