JPH06124036A - Electrifier - Google Patents

Abstract

PURPOSE:To provide an electrifier capable of preventing the breaking of an electrifying wire and always keeping the tensile force of the electrifying wire constant by simplifying the winding route of the electrifying wire. CONSTITUTION:In the electrifier constituted including the electrifying wire 6, a pulley for supplying the electrifying wire 6 and a take-up pulley 13 and extending the electrifying wire 6 between both pulleys 4 and 13, a torque limiter is included in the take-up pulley 13 and also, a means for stopping rotation in the direction opposite to the taking up direction of the take-up pulley 13 is provided. Thus, the torque limiter is included in the take-up pulley 13 so that a wire tension pulley is not required, the winding route of the electrifying wire 6 is simplified to reduce the probability of the occurrence of the breaking of the electrifying wire 6 and also, always keep the tensile force of the electrifying wire 6 constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device in an image forming apparatus.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic apparatus, an electrostatic recording apparatus and a magnetic recording apparatus, a charging device for applying a voltage to a discharge wire to generate a discharge charges a photosensitive drum as an image carrier. It is well known in the art to be used as a charging device, a transfer device for transferring an image from a photosensitive drum onto paper, a separator for separating the paper from the photosensitive drum, and a static eliminator for neutralizing the photosensitive drum. In general, this type of charging device stretches a charging wire such as tungsten via wire fixing tools provided at both ends of the conductive shield case, and applies high voltage electricity to the charging wire to generate corona discharge. In this way, the surface of the photosensitive drum is charged by this.

By the way, in an image forming apparatus, a powder developer (hereinafter referred to as toner) is supplied to a latent image formed on a photosensitive drum, an insulating drum, a magnetic drum or the like as an image carrier to form the latent image. It is equipped with a developing device for visualizing.

However, the above-mentioned toner scatters along with the airflow that flows in the vicinity of the surface layer of the image carrier due to the movement of the image carrier, and not only causes pollution in the image forming apparatus, but also in the image forming apparatus. Adversely affect the operation of various image forming means. For example, if the scattered toner adheres to a charging device, a transfer separation device, or the like, uneven charging may occur,
The current may easily leak, and problems such as transfer failure, separation failure, and contamination of transfer material (paper or the like) may occur.

As means for solving the above problems, conventionally,
There is known a system in which a charging wire of a charging device is (automatically) fed and wound up after every predetermined number of copies and replaced with a new wire portion (US Pat. No. 3,499,1).
No. 43, Japanese Utility Model Laid-Open No. 47-9433, JP-A No. 50-345
No. 42), and in order to prevent the vibration noise of the charging wire during discharging, and to prevent the fluctuation of the height due to the vibration of the charging wire during discharging, in the charging device of the type that feeds out the charging wire. In addition, a structure in which a tensioner member is biased by using a tension spring or the like is generally adopted for the charging wire.

[0006]

However, in the structure in which the tensioner member applies tension to the charging wire, there is a possibility that the following problems may occur. That is,
By using the tensioner member, the winding path of the charging wire becomes complicated, the winding workability of the charging wire becomes poor, and the contact amount between the charging wire and other pulleys including the tensioner member increases, which in turn Has a high probability of wire breakage, which is a problem in terms of reliability.

In order to solve the above-mentioned problems, it has been proposed to incorporate a spiral spring in the wire reel. In this structure, the tension of the charging wire changes as the feeding of the charging wire progresses from the wire reel. There is a problem and it is impossible to completely prevent wire slack or wire breakage.

Therefore, the object of the first aspect of the present invention is to simplify the winding path of the charging wire to prevent the breakage of the charging wire and to keep the tension of the charging wire constant at all times. To provide a charging device.
By the way, when the charging wire is newly stretched or when the charging wire is cut for some reason and must be re-stretched, the work is difficult and the serviceability is poor.

Therefore, the object of the second invention is to provide a charging device which can easily stretch the charging wire and can prevent the once stretched charging wire from loosening or coming off. Especially.

On the other hand, in the conventional charging device, toner, dust and the like are attracted and adhered to the unused charging wire portion wound around the feeding pulley due to discharge,
There is a problem in that the charging wire becomes dirty and the discharge effect is reduced, and uneven charging and leakage easily occur.

Therefore, an object of the third invention is to provide a charging device capable of preventing the charging wire from being contaminated and suppressing uneven charging and leakage.

Further, in the conventional charging device, since the pulley for winding the charging wire is directly driven, stress is applied to the charging wire at the pulley portion. It is easily deteriorated due to the adhesion of dust and the like.

When the charging wire is broken,
Since there is no special holding means for the charging wire, not only the charging wire after use but also the unused charging wire is scattered, and a serviceman must be called to newly stretch the charging wire. Since it takes time for the service person to reattach the charging wire, the image forming apparatus stops during that time.

Therefore, the object of the fourth aspect of the invention is to prevent the charging wire from being cut so that the charging function is not lost even if the charging wire is cut, and the charging device can be easily replaced. To provide.

By the way, in the conventional charging device, the cleaning member is provided so that the unused charging wire wound around the feeding pulley becomes dirty, but this cleaning member is contacted with the charging wire, or Alternatively, since it is sandwiched, it becomes a hindrance when replacing the charging wire, and there is a problem that the exchangeability of the charging wire is significantly impeded.

Therefore, an object of the fifth invention is to provide a charging device which can improve the exchangeability of the charging wire.

By the way, in the conventional charging device, the cleaning of the charging wire is stopped until the serviceman replaces it with a new pulley at the time when all the charging wires of the feeding pulley are paid out, and the deterioration of the image occurs. Will end up. In addition, when the charging wire is gradually fed out depending on the number of copies, there is a problem that the life per unit length of the charging wire becomes extremely shorter than that of a normal charging wire that is stretched.

Therefore, an object of the sixth invention is to provide a charging device capable of extending the life of the charging wire.

[0019]

In order to achieve the above object, a first aspect of the present invention comprises a charging wire, a feeding pulley and a winding pulley for the charging wire, and the charging wire is stretched between the pulleys. In the charging device formed by mounting,
The winding pulley is provided with a means for enclosing a torque limiter therein and for preventing rotation of the winding pulley in a direction opposite to the winding direction.

According to a second aspect of the present invention, there is provided a charging device comprising a charging wire, a feeding pulley and a winding pulley for the charging wire, wherein the charging wire is stretched between the two pulleys. One of the features is that a one-way clutch is provided.

A third aspect of the present invention is a charging device comprising a charging wire, a pulley for feeding out the charging wire, and a winding pulley, wherein the charging wire is stretched between both pulleys. Is arranged upstream of the discharge area with respect to the blower.

A fourth aspect of the present invention is a charging device comprising a charging wire, a charging wire feeding means, and a charging wire winding means, wherein the charging wire is at least between the charging wire feeding means and the charging use area. Charging wire supporting and conveying means for supporting and conveying the charging wire at the same time is provided between the winding means and the charging use area.

A fifth aspect of the present invention is a charging device comprising a charging wire, a pulley for feeding the charging wire, and a winding pulley, wherein the charging wire is stretched between both pulleys. Alternatively, the charging wire is released in association with the removal of at least one of the winding pulleys.

A sixth aspect of the present invention is a charging device comprising a charging wire, a pulley for feeding the charging wire and a pulley for winding the charging wire, wherein the charging wire is stretched between both pulleys. Control means for controlling the feeding from the feeding pulley in the winding pulley direction (first direction) and control means for controlling the feeding of the charging wire from the winding pulley in the feeding pulley direction (second direction). Is provided.

[0025]

According to the first aspect of the present invention, since the winding limiter includes the torque limiter therein, the pulley for wire tension is not required, and the winding path of the charging wire is simplified and the charging wire is broken. The probability is reduced and the tension of the charging wire can be kept constant at all times.

According to the second aspect of the invention, for example, if the winding pulley is provided with a one-way clutch, the winding pulley can be freely rotated with respect to the drive source when the charging wire is stretched. Wiring work is facilitated and serviceability is improved. Further, since the pulley does not rotate in the reverse direction, the once-tensioned charging wire will not be loosened or come off.

According to the third aspect of the present invention, since the feeding pulley is arranged on the upstream side of the blower with respect to the discharge area of the charging wire, toner or toner is not applied to the unused portion of the charging wire wound around the feeding pulley. Prevents dust from collecting,
Contamination of the charging wire is prevented and uneven charging and leakage are suppressed.

According to the fourth aspect of the present invention, since tension or stress is not directly applied to the feeding portion and the winding portion of the charging wire, the charging wire is prevented from being cut, and even if the charging wire is cut, it is used. Alternatively, there is no fear that the unused charging wire will fall apart, and the charging device will not lose its function unless the charging wire is cut in the charging use area, and it is not necessary to stop the image forming apparatus. In addition, the workability of recharging the charging wire is also improved.

According to the fifth aspect of the invention, since the cleaning member for the charging wire is released in association with the attachment / detachment of the pulley, the cleaning member does not get in the way when the charging wire is replaced, and the exchangeability of the charging wire is improved. To be

According to the sixth aspect of the present invention, when the charging wire is unwound, the wound charging wire is unwound in reverse to recycle the charging wire, so that the life of the charging wire can be extended. .

[0031]

【Example】

[First Invention] An embodiment of the first invention will be described below with reference to the accompanying drawings.

<First Embodiment> A first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a perspective view in which a part of the charging device according to the first embodiment is broken away, and in this figure, the detailed structure for positioning to the copying machine is omitted. 2 is an exploded perspective view of the pulley and the sleeve shaft.

In the figure, 1 is a shield plate made of a material such as SUS, and 2 and 3 are front and rear blocks made of nonflammable resin. Reference numeral 4 denotes a pulley rotatably supported around a shaft 5 integral with the front block 2, and an unused charging wire 6 is wound around the pulley 4 a plurality of times.

Further, 7 and 8 are wire pulleys provided on the rear block 3 side, and the pulleys 7 and 8 are rotatably supported by metal shafts 10 and 11 provided upright on a support plate 9. A charging wire 6 is wound around them as shown.

By the way, the support plate 9 is fixed to the rear block 3 by a long screw 12, and the top of the long screw 12 contacts a high-voltage connector of the main body of the copying machine (not shown). Is supplied. Therefore, high voltage power is supplied to the charging wire 6 from the support plate 9 through the shafts 10 and 11 and the metal pulleys 7 and 8.

Then, the other end of the charging wire 6 fed from the pulley 4 passes through the pulleys 7 and 8 and the pulley 13
To be wound up. The pulley 13 constitutes a so-called torque mitter capable of rotating with a constant torque, and as shown in FIG.
A medium such as magnetic powder is enclosed between the pulley 13 which is the housing and the sleeve shaft 14 which is fitted therein, and the pulley 13 is rotatable on the shaft 15 which is integral with the front block 2. Supported by. Then, when the torque is equal to or higher than the constant torque, the sleeve shaft 14 idles with respect to the pulley 13. A handle portion 14a is integrally formed with the sleeve shaft 14.

Further, a spur gear 13a is integrally formed on the pulley 13, and the gear 13a is rotatably supported by a shaft 16 which is integral with the front block 2 and has only one direction inside thereof. A gear 17 having a built-in one-way clutch that allows rotation (in the present example, the feeding direction of the charging wire 6 (arrow direction)) is meshed. With this configuration, rotation of the pulley 13 in the direction opposite to the wire winding direction is blocked, and the loosening of the charging wire 6 is prevented.

Further, a screw 18 is provided on the feeding side of the charging wire 6 of the front block 2, and the charging wire 6 is provided.
One end of is fixed by a screw 18.

With the above construction, when the charging wire 6 is replaced, the work is carried out in the following procedure.

First, the screw 18 fixing one end of the charging wire 6 is loosened.

Next, the handle portion 14a of the sleeve shaft 14 of the pulley 13 is operated to rotate the pulley 13, the used charging wire 6 is wound around the pulley 13, and the pulley 4 is rotated.
The unused charging wire 6 is fed out from.

When the replacement of the charging wire 6 is completed, the screw 18 is tightened to fix one end of the charging wire 6, and then the handle portion 14a of the sleeve shaft 14 is operated to further wind the charging wire 6 around the pulley 13. take. Since the pulley 13 has a built-in torque limiter as described above, the sleeve shaft 14 idles with respect to the pulley 13 when the torque exceeds a predetermined wire tension, so that the charging wire 6 is stretched with a predetermined tension. Will be hung. After the charging wire 6 is stretched, the pulley 13 is prevented from being reversed by the gear 17 having the built-in one-way clutch as described above, so that the charging wire 6 is not loosened.

<Second Embodiment> Next, a second embodiment will be described with reference to FIGS. Incidentally, FIG. 3 is a perspective view in which a part of the charging device according to the second embodiment is cut away, and FIG. 4 is an exploded perspective view of a pulley and a sleeve shaft of the charging device. In these drawings, FIGS. The same elements as those indicated by are denoted by the same reference numerals.

In this embodiment, the winding pulley 19 of the charging wire 6 and the sleeve shaft 20 constitute a torque liter, and the sleeve shaft 20 is integrally formed with the gear 20a. It is rotatably supported by a shaft 15 which is integral with the block 2. As in the first embodiment, the gear 20a meshes with the gear 17 having a built-in one-way clutch for preventing reverse rotation, and the gear 22 of the motor 21 for driving the pulley 13 fixed to the front block 2 meshes with the gear 20a. There is.

The pulley 4 on the payout side is provided with a cylindrical portion 4a whose surface is covered with rubber.
The same roller 23 made of rubber is in contact with.

The roller 23 is attached to a lever 25 having a shaft 24 integral with the front block 2 as a rotation center, and the lever 25 is rotated by a tension spring 26 hooked on a part of the front block 2. The roller 23 is urged to rotate in a direction in which it contacts the cylindrical portion 4a of the pulley 4.

Further, a solenoid 27 is attached to the lever 25, and the operation of the solenoid 27 causes the roller 2 to move.
3 is configured to be rotationally biased in a direction away from the cylindrical portion 4a of the pulley 4.

Thus, in this embodiment, the charging wire 6 is automatically replaced when a predetermined number of copies is reached. That is, when a predetermined number of sheets are counted by the microprocessor unit (MPU) of the copying machine body,
The solenoid 27 is actuated and the roller 23 is separated from the cylindrical portion 4a of the pulley 4, so that the pulley 4 is free to rotate.

After that, the motor 21 is energized to wind the charging wire 6 and the unused charging wire 6 is paid out from the pulley 4. By controlling the exchange of the charging wire 6 of a predetermined length by the operating time of the motor 21, when the motor 21 is stopped and the exchange of the charging wire 6 is completed, the energization of the solenoid 27 is stopped and the roller 23 is rotated by the spring 26. Is urged by the cylindrical portion 4a of the pulley 4
And the feeding side of the charging wire 6 is fixed.

After that, the winding pulley 19 is rotated via the sleeve shaft 20 so as to energize the motor 21 and apply tension to the charging wire 6. At this time, since the pulley 19 and the sleeve shaft 20 compose a torque limiter as described above, when the torque corresponding to a predetermined wire tension or more is exceeded, the sleeve shaft 20 idles with respect to the pulley 19 and the charging wire is charged. 6 is stretched with a predetermined tension.

In the above embodiments, the charging wire 6 is reciprocated and wound. However, if the pulleys 7 and 8 are replaced by the payout side pulley 4, the charging wire is not reciprocated and wound ( That is, it is clear that the present invention can be applied to a single wire system instead of two. [Second Invention] An embodiment of the second invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 5 is a partially cutaway plan view of the charging device according to the first embodiment of the second invention, and FIG. 6 is a side cross-sectional view of the charging device partially broken. .

In the figure, 1 and 1'denotes shield plates, 2 front blocks, 3 rear blocks, and 6 charging wires.

Further, 4 is a payout pulley, 13 is a take-up pulley, and the charging wire 6 wound around the payout pulley 4 passes through a power feeding pulley 7 and is wound around the take-up pulley 13. Has been.

The power feeding pulley 7 is rotatably supported by the shaft 10 fixed to the electrode 29, and has a power feeding side screw 31.
A high voltage is applied to the charging wire 6 through the electrode 29, the shaft 10 and the power feeding pulley 7.

Thus, in this embodiment, the winding pulley 1
3 is supported by a shaft 15 fixed to the front block 2 via a one-way clutch 33 so as to be rotatable only in the direction of arrow A in the figure. The take-up pulley 13 is provided with teeth, and a gear 34 meshes with the teeth. The gear 34 is rotationally driven by the motor 36 via the one-way clutch 35.

The motor 36 causes the gear 34 to rotate in the direction of arrow B in the figure, and as a result, the winding pulley 13 rotates in the direction of arrow A to wind the charging wire 6.

Thus, when the charging wire 6 is broken,
To reattach the charging wire 6, it is only necessary to manually rotate the winding pulley 13 in the direction of the arrow A. At this time, the one-way clutch 35 works to rotate the gear 34 freely with respect to the motor 36. Since the rotational force of the take-up pulley 13 is not transmitted to the motor 36 and the take-up pulley 13 does not reverse, the take-up pulley 13 is once wound around the take-up pulley 13. The charging wire 6 does not come loose or come off. When the charging wire 6 is stretched, the charging wire 6 is placed on the positioning portions 37, 38, 3
By passing through 9, the height of the stretched charging wire 6 is kept constant.

As shown in FIG. 7, the winding pulley 13 may be supported by the output shaft 40 of the motor 36 via the one-way clutch 33. At this time, it is necessary to prevent the winding pulley 13 from rotating in the reverse direction by the gear head of the motor 36.

<Second Embodiment> Next, a second embodiment of the second invention will be described with reference to FIGS. 8 and 9. In addition, FIG. 8 shows the second
FIG. 9 is a plan view of a drive system of the charging device according to the embodiment, and FIG. 9 is a sectional view of the same side.

Since tension must be applied to the charging wire 6 when the charging wire 6 is stretched, in the present embodiment, the feeding pulley 4 is provided with a brake (not shown).

When the charging wire 6 is stretched, it is possible to wind the charging wire 6 around the winding pulley 13 while visually observing the winding wire, and sometimes while slightly feeding the feeding pulley 4.

However, when the charging wire 6 is set on the image forming apparatus and wound on the winding pulley 13 by the driving force of the motor 36, the tension applied to the charging wire 6 becomes unstable and sometimes becomes excessive. As a result, the charging wire 6 may be broken. Therefore, the charging wire 6 is previously
It becomes difficult to set the tension applied to the.

Therefore, in this embodiment, the winding pulley 13 is supported on the shaft 15 via the one-way clutch 33, and the gear portion thereof is rotatably supported on the shaft 41 fixed to the front block 2. It meshes with the gear 42.

The gear 42 is the output shaft 40 of the motor 36.
And meshes with a gear 34 supported via a one-way clutch 35. And one more on the output shaft 40
One gear 43 is supported via a one-way clutch 44. The rotation lock directions of the one-way clutches 35 and 44 are the same as the output shaft 40.

The gear 43 meshes with a gear 46 rotatably supported by a shaft 45 fixed to the front block 2,
It also meshes with the gear portion engraved on the feeding pulley 4.

Thus, when the winding pulley 13 is manually rotated, the output shaft 40 of the motor 36 is rotated from the gear 42 side through the feeding pulley 4 which rotates as the charging wire 6 is wound. Rotational force is not transmitted from the side either. On the contrary, when the motor 36 is driven, the driving force can be transmitted to the feeding pulley 4 and the winding pulley 13.

It is also possible to apply tension to the charging wire 6 after pulling the charging wire 6 by pulling the feeding pulley side (not shown) with a spring or the like, instead of braking the feeding pulley 4. . Further, after pulling the charging wire 6, the front block 2 and the like are displaced to widen the distance between the power feeding pulley, the feeding pulley 4, and the winding pulley 13, whereby tension can be applied to the charging wire 6. [Third Invention] An embodiment of the third invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
A description will be given based on 0. 10 is a plan view of the charging device according to this embodiment.

In FIG. 10, 4 is a feeding pulley,
A winding pulley 13 is driven by a drive motor (not shown).

The drive motor is controlled by the main body of the image forming apparatus (not shown), so that the charging wire 6 is wound around the winding pulley 13.

Thus, in this embodiment, when the charging wire 6 is discharged, the air blower 50 blows air toward the feeding pulley 4, and the wind winds up through the shield plate 1 which also serves as a duct. It is sent to the pulley 13. This prevents the scattered toner and dust from adhering to the discharge wire 6 wound around the delivery pulley 4, prevents the charging wire 6 from becoming dirty, and suppresses uneven charging and leakage. .

Further, by guiding the flow of wind to the ozone removing device 51, the ozone generated by the discharge is removed.

<Second Embodiment> Next, a second embodiment of the third invention will be described with reference to FIG. Note that FIG. 11 is a plan view of the charging device according to the second embodiment.

In this embodiment, the drive gear 47 drives the feeding pulley 4 and the winding pulley 13, and the charging wire 6 is sent via the relay pulley 48.

Thus, also in this embodiment, the blower 5
0 for feeding out pulley 4 and winding pulley 13
The air is blown toward and is guided to the ozone removing device 51 through the shield plate 1 which also serves as a duct, and the same effect as that of the first embodiment is obtained. [Fourth Invention] An embodiment of the fourth invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 12 is a plan view of a charging device according to a first embodiment of the present invention. In FIG. 12, 1 is a shield plate, 2 and 3 are front and rear blocks, respectively.
12 is a power feeding unit.

Further, 7 is a tensioner pulley, and the tensioner pulley 7 is attached to a support member 9 attached to the rear block 3, which is urged by a tension spring 38 serving as tensioner pulley urging means to charge the charging wire. 6 is given a constant tension. The tensioner pulley 7 is made of a conductive material (such as brass) and changes the direction of the charging wire 6. Further, the tensioner pulley 7 is integrated with the power feeding unit 12, and the high voltage applied to the power feeding unit 12 is conducted to the charging wire 6.

Further, 4 is a charging wire feeding pulley, 13 is a charging wire winding pulley, 52 is a pulley pressing roller (52a is a feeding side roller, 52b a winding side roller), and 53 is a charging wire conveying belt (53).
a is a feeding side belt, 53b is a winding side belt),
Reference numeral 54 is a conveyor belt driving roller, 55 is a charging wire supporting roller (55a is a feeding side roller, and 55b is a winding side roller) and is driven by the conveyor belt 53.

The charging wire 6 is supported by the charging wire conveying belt 53 and the supporting roller 55, and is charged by the leaf spring 56 (56a is a feeding side spring and 56b is a winding side spring) attached to the front block 2. The wire 6 is pressed with a force larger than the tension of the wire 6 (the wire pull-out force is pressed so as to be larger than the tension of the wire), and the charging wire 6 is fed by the driving of the conveyor belt drive roller 54. ing.

Further, the charging wire 6 wound around the feeding pulley 4 and the winding pulley 13 has the feeding pulley 4 and the winding pulley pressing roller 52b at a predetermined pressure.
The charging wire 6 is pressed by the charging wire transport belt 53 by the
Even when the charge is cut, the unused charging wire 6 and the used charging wire 6 wound around the feeding pulley 4 and the winding pulley 13 do not come apart. As described above, the charging wire support roller 55 presses the charging wire 6 so that the wire pull-out force becomes larger than the tension of tension, but since the charging wire 6 is biased by the leaf spring 56, this biasing force is applied. The roller pressure can be released by a force in the opposite biasing direction which is greater than the pressure. Further, at least the surfaces (surface layers) of the charging wire supporting roller 55 and the charging wire transport belt 53 are made of an insulating member having a predetermined elasticity.

Next, the drive unit of the charging wire transport belt 53 will be described with reference to FIGS. 13 and 14. 13 is a plan view of the drive unit, and FIG. 14 is a side sectional view of the drive unit.

When the charging wire 6 begins to deteriorate due to toner scattering or the like, a signal for a step angle corresponding to the stretched length of the charging wire 6 which has been used until now is supplied from a main body control device (not shown) to a drive motor. Applied to M. Then, the conveyor belt drive roller 54b is provided via a gear 54b 'provided coaxially or integrally with the conveyor belt drive roller 54b.
Rotation of the conveyor belt driving roller 5
Via a conveyor belt 53b suspended on 4b, a gear 52b 'provided coaxially or integrally with the winding pulley pressing roller 52b, and a gear 13' provided coaxially or integrally with the winding pulley 13 Take-up pulley 1
3 rotates counterclockwise. As a result, the deteriorated charging wire 6 is wound around the winding pulley 13, and at the same time, the gears 54b ′, 57 and the conveyor belt driving roller 54 are wound.
The conveyor belt drive roller 54a rotates clockwise through a gear 54a 'that is the same as or integrally provided with a,
By this rotation, the conveyor belt 53a suspended by the conveyor belt drive motor 54a, the gear 52a 'provided coaxially or integrally with the feeding pulley pressing roller 52a,
The unused charging wire 6 is fed from the feeding pulley 4 by a length of the charging wire 6 which has been used so far, via a gear 4 ′ provided coaxially or integrally with the feeding pulley 4.

<Second Embodiment> Next, a second embodiment of the fourth invention will be described with reference to FIG. 15 is a plan view of the charging device according to the second embodiment.

In FIG. 15, reference numeral 60 is a pulley pressing roller (60a is a payout side roller, 60b is a take-up side roller), 61 is a charging wire carrying drive roller (61a is a payout side roller, 61b is a takeup side roller), and 62 is a reference numeral. Is a charging wire supporting roller (62a is a feeding side roller,
62b is a winding side roller, 63 is a charging wire supporting roller urging spring (63a is a feeding side spring, and 63b is a winding side spring).

Thus, in this embodiment, at least the surface (surface layer) of each roller 60, 61, 62, 63 is made of an insulating material having a predetermined elasticity. In the first embodiment, the charging wire 6 is supported by the conveyor belt 53 at a predetermined pressure, whereas in the present embodiment, the roller pairs 60 to 63 directly support the charging wire 6 by a predetermined pressure. It is designed to be transported.

<Third Embodiment> Next, a third embodiment of the fourth invention will be described with reference to FIG. 16 is a plan view of the charging device according to the third embodiment.

In FIG. 16, 70 is a pulley pressing roller, 71 is a charging wire conveying roller, 72 is a charging wire supporting roller (72a is a feeding side roller, 72b is a winding side roller), and 73 is a charging wire supporting roller urging spring. (73a is a feeding side spring and 73b is a winding side spring).

In the first and second embodiments, the pulley pressing rollers 52 and 60 and the transport driving rollers 54 and 61 are independently provided on the feeding side and the winding side, respectively. One pulley retainer roller 7
0, the charging wire 6 is sandwiched by a transport roller 71 at a predetermined pressure and transported. Further, similarly to the second embodiment, at least the surface (surface layer) of each roller 70, 71, 72 is made of an insulating member having a predetermined elasticity.

In the above second and third embodiments, as the pulley pressing member, the rollers 60 and 70, at least the surfaces of which are made of an insulating material having a predetermined elasticity, are used. It may be composed of an insulating felt pad or the like that is not damaged, and if the supporting member of the pulley pressing member has a predetermined elasticity, it is not necessary to give elasticity to the pulley pressing member.

Further, in the above-mentioned first to third embodiments,
Although the charging wire 6 is made to make a U-turn,
By providing the pulleys 4 and 13 on the rear block 3 side and providing a means for conducting the high voltage applied to the power feeding section 12 between the supporting and conveying means, the same effect can be obtained even if the charging wire 6 does not make a U-turn. It is possible to obtain. [Fifth Invention] An embodiment of the fifth invention will be described below with reference to the accompanying drawings.

FIG. 17 is a plan view of a charging device according to the fifth invention, FIG. 18 is a side view of a feeding pulley of the charging device,
19 is a plan view of the feeding pulley, FIG. 20 is a side view when the feeding pulley is inserted, and FIG. 21 is a plan view showing a state (released state) of the cleaning member when the feeding pulley is removed.

In the figure, 4 is a feeding pulley, 13
Is a winding pulley driven by a drive motor (not shown).

The drive motor is controlled by the main body of the image forming apparatus (not shown), and the charging wire 6 is fed by the feeding pulley 4.

By the way, the feeding pulley 4 has
A cleaning member 80 formed of an elastic body is provided, and the cleaning member 80 removes toner and dust attached to the charging wire 6 of the feeding pulley 4 when a voltage is applied to the charging wire 6. The cleaning member 80 is the shaft 8
The intermediate portion of the link 83 is rotatably attached to the front ends of a pair of links 83, and a return spring 84 is interposed between the other ends of the links 83.
Is urged in the opening (release) direction of the cleaning member 80.

By the way, the feeding pulley 4 is shown in FIG.
As shown in FIG. 7, the receiving shaft 86 slidably inserted from the left side of the drawing, and thereby freely supported by the spring 85.
18 comes into contact with the shaft 4a of the feeding pulley 4 and escapes, and the receiving shaft 86 eventually fits with the shaft 4a of the feeding pulley 4 as shown in FIG. By engaging the member 80 with the link 83, the cleaning member 8
When 0 is closed, the charging wire 6 is sandwiched as shown in FIG. 19 to clean it.

Thus, in this embodiment, the link 83 is rotated about the shaft 82 by the return spring 84 as shown in FIG. 21 in conjunction with the operation of removing the feeding pulley 4, and the cleaning member 80 is released. Therefore, the cleaning member 80 does not get in the way when the charging wire 6 is replaced,
The exchangeability of is improved.

FIG. 22 shows another embodiment of the structure for releasing the cleaning member 80. [Sixth Invention] An embodiment of the sixth invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 23 is a plan view of a charging device according to a first embodiment of the sixth invention, and FIGS. 24 and 25 are side sectional views of the charging device.

In the charging device according to this embodiment, the rotation of the drive motor 90 capable of forward and reverse rotation is transmitted to the winding pulley 13 via the drive belt 91, and the charging wire 6 is wound from the feeding pulley 4 to be wound. It is sent in the direction of the pulley 13 (first direction).

In this embodiment, the feeding pulley 4 or the winding pulley 13 is made of a conductive member, and a voltage is applied to the charging wire 6 via the pulley 4 or 13 made of a conductive member. Discharge occurs on the charging wire 6. In the figure, 1 is a shield plate.

The discharge of the charging wire 6 causes the scattered toner and dust in the image forming apparatus to adhere to the unused charging wire 6 of the feeding pulley 4, so that charging is performed through the wire cleaning member 92 composed of an elastic member. The wire 6 is unwound, and the unwound charging wire 6 passes through the image forming area to remove toner and dust adhering to the image forming area by the wire cleaning member 93 made of an elastic member, and then is wound around the winding pulley 13. It is stored and stored.

When the charging wire 6 is fed out and the charging wire 6 of the feeding pulley 4 is fed to the end (FIG. 25), the conductive flag 94 connected to the charging wire 6 is pulled out from the feeding pulley 4, and this is detected by the sensor. 95, the feeding of the charging wire 6 is stopped.

Then, after a fixed amount of image (amount not causing image deterioration) is formed, the reverse rotation is controlled, the drive motor 90 is rotated in the reverse direction, and the discharge wire 6 having a substantially image forming region length is wound. It is sent from the take-up pulley 13 in the direction of the pay-out pulley 4 (second direction) and is wound around the pay-out pulley 4. This is because the charging wire 6 for this area has not been cleaned after discharging, and is wound outside during image formation to prevent image defects. By such reverse rotation control of the drive motor 90, the pulley 4 that has been operating as a payout pulley until now is taken up.
As a result, the charging wire 6 that has been used once can be cleaned and reused, and the life of the charging wire can be extended.

By the way, a sensor 96 is also provided on the winding pulley 13 side, and the driving is stopped by detecting a sensor (not shown) that appears when the charging wire 6 is fed to the end. Alternatively, reverse rotation control is performed. The serviceman call may be displayed on the operation unit by detecting the flag by the sensor 96.

The sensors 95 and 96, the cleaning member 92,
The flag 93 and the flag 94 are installed outside the image forming area of the charging wire 6.

By the way, as a method of feeding the charging wire 6, there are a method of always feeding at a constant speed and a method of intermittently feeding a fixed amount outside the image formation.

<Second Embodiment> Next, a second embodiment of the sixth invention will be described with reference to FIGS. Incidentally, FIG.
27 and 27 are plan views of the charging device according to the second embodiment.

In this embodiment, the feeding pulley 4 and the winding pulley 13 are rotated by the drive motor 90,
The charging wire 6 is sent out via the relay pulley 97. The relay pulley 97 is made of a conductive member, and a voltage is applied to the charging wire 6 via the relay pulley 97 to cause discharge on the charging wire 6.

The discharge of the charging wire 6 causes the scattered toner and dust to adhere to the unused charging wire of the feeding pulley 4, so that the cleaning member 92 made of an elastic member is sent out through the charging wire 6 and the charging wire 6 is discharged. Passes through the image forming area via the relay pulley 97, and after the toner and dust adhering to the image forming area is removed by the cleaning member 92,
It is wound up and stored on the winding pulley 13.

When the charging wire 6 of the feeding pulley 4 is fed to the end as shown in FIG. 27, the pulley 4
When the flag 94 wound around is pulled out and the flag 94 is detected by the sensor 95, the drive motor 90 is controlled to rotate in the reverse direction, and the charging wire 6 is fed backward.
As a result, the charging wire 6 is reused as in the first embodiment, and the life of the charging wire 6 is extended.

A flag (not shown) is also provided on the pulley 13 side, which has been used as a winding pulley up to now, similarly to the pulley 4, and the flag is provided by the sensor 96.
Is detected, the drive motor 90 is stopped and the reverse rotation is controlled.

[0114]

As is apparent from the above description, according to the first aspect of the present invention, since the winding pulley has the torque limiter therein, the pulley for wire tension is not required, and the winding path of the charging wire is eliminated. Is simplified and the probability of breakage of the charging wire is reduced, and the tension of the charging wire can be always kept constant.

According to the second aspect of the invention, for example, if the winding pulley is provided with a one-way clutch, the winding pulley can be freely rotated with respect to the drive source when the charging wire is stretched. Wiring work is facilitated and serviceability is improved. Further, since the pulley does not rotate in the reverse direction, the once-tensioned charging wire will not be loosened or come off.

According to the third aspect of the invention, since the feeding pulley is arranged on the upstream side of the blowing device with respect to the discharge area of the charging wire, toner or toner is not collected on the unused portion of the charging wire wound around the feeding pulley. Prevents dust from collecting,
Contamination of the charging wire is prevented and uneven charging and leakage are suppressed.

According to the fourth invention, tension or stress is not directly applied to the feeding part and the winding part of the charging wire, so that the charging wire is prevented from being cut, and even if the charging wire is cut, it is used. Alternatively, there is no fear that the unused charging wire will fall apart, and the charging device will not lose its function unless the charging wire is cut in the charging use area, and it is not necessary to stop the image forming apparatus. In addition, the workability of recharging the charging wire is also improved.

According to the fifth aspect of the invention, since the cleaning member for the charging wire is released in association with the attachment / detachment of the pulley, the cleaning member does not get in the way when the charging wire is replaced, and the exchangeability of the charging wire is improved. To be

According to the sixth aspect of the present invention, when the charging wire is unwound, the wound charging wire is unwound to recycle the charging wire, so that the life of the charging wire can be extended. .

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a charging device according to a first exemplary embodiment of the first invention.

FIG. 2 is an exploded perspective view of a pulley and a sleeve shaft of the charging device according to the first exemplary embodiment of the first invention.

FIG. 3 is a partially cutaway perspective view of a charging device according to a second embodiment of the first invention.

FIG. 4 is an exploded perspective view of a pulley and a sleeve shaft of a charging device according to a second embodiment of the first invention.

FIG. 5 is a partially cutaway plan view of the charging device according to the first exemplary embodiment of the second invention.

FIG. 6 is a side sectional view in which a part of the charging device according to the first embodiment of the second invention is cut away.

FIG. 7 is a side sectional view of a main part of a charging device according to a modification of the first embodiment of the second invention.

FIG. 8 is a plan view of a drive system of the charging device according to the second exemplary embodiment of the second invention.

FIG. 9 is a side sectional view of a drive system of the charging device according to the second exemplary embodiment of the second invention.

FIG. 10 is a plan view of the charging device according to the first exemplary embodiment of the third invention.

FIG. 11 is a plan view of a charging device according to a second embodiment of the third invention.

FIG. 12 is a plan view of the charging device according to the first exemplary embodiment of the fourth invention.

FIG. 13 is a plan view of a driving unit of the charging wire transport belt of the charging device according to the first exemplary embodiment of the fourth invention.

FIG. 14 is a side sectional view of a driving unit of a charging wire transport belt of a charging device according to a first exemplary embodiment of the fourth invention.

FIG. 15 is a plan view of a charging device according to a second embodiment of the fourth invention.

FIG. 16 is a plan view of a charging device according to a third embodiment of the fourth invention.

FIG. 17 is a plan view of a charging device according to a fifth aspect of the invention.

FIG. 18 is a side view of a feeding pulley of the charging device according to the fifth aspect of the invention.

FIG. 19 is a plan view of a feeding pulley of a charging device according to a fifth aspect of the invention.

FIG. 20 is a side view showing a state when the feeding pulley is inserted.

FIG. 21 is a plan view showing a state (released state of the cleaning member) when the feeding pulley is removed.

FIG. 22 is a view similar to FIG. 21 according to another embodiment of the fifth invention.

FIG. 23 is a plan view of the charging device according to the first exemplary embodiment of the sixth invention.

FIG. 24 is a side sectional view of the charging device according to the first exemplary embodiment of the sixth invention.

FIG. 25 is a side sectional view of the charging device according to the first exemplary embodiment of the sixth invention.

FIG. 26 is a plan view of the charging device according to the second embodiment of the sixth invention.

FIG. 27 is a plan view of the charging device according to the second embodiment of the sixth invention.

[Explanation of symbols]

 4 Pulling Pulley 6 Charging Wire 13 Winding Pulley 33, 35, 44 One Way Clutch 50 Blower 52, 60, 70 Pulley Holding Roller 53 Charging Wire Conveying Belt 54 Conveying Belt Driving Roller 55, 62, 72 Charging Wire Supporting Roller 61 , 71 Charging wire transport drive roller 80 Cleaning member 90 Drive motor 92, 93 Cleaning member 94 Flag 95, 96 Sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriaki Koyanagi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (21)

[Claims] 1. A charging device comprising a charging wire, a feeding pulley and a winding pulley for the charging wire, wherein the charging wire is stretched between both pulleys, and a torque is applied to the winding pulley. A charging device comprising a limiter and means for preventing rotation of a winding pulley in a direction opposite to a winding direction. 2. A charging device comprising a charging wire, a feeding pulley and a winding pulley for the charging wire, wherein the charging wire is stretched between both pulleys, and at least one of the pulleys is one-way. A charging device having a clutch. 3. The charging device according to claim 2, wherein a driving force from a driving source is transmitted to at least one of the pulleys, and one-way clutches are provided on the pulley and the driving source, respectively. 4. The charging device according to claim 2, wherein a one-way clutch is provided in each of the driving force transmission paths between the both pulleys and a driving source that drives the pulleys. 5. A charging device comprising a charging wire, a pulley for feeding the charging wire and a winding pulley, wherein the charging wire is stretched between both pulleys. The charging device is characterized in that it is arranged on the upstream side of the discharge area. 6. A charging device including a charging wire, a charging wire feeding means, and a charging wire winding means, wherein the charging wire winding means is at least between the charging wire feeding means and the charging use area. 2. A charging device, comprising: a charging wire supporting and conveying means for supporting and conveying the charging wire at the same time between a charging area and a charging use area. 7. The charging device according to claim 6, wherein the charging wire feeding means and the charging wire winding means are interlocked with or driven by the charging wire supporting and conveying means. 8. The charging device according to claim 6, wherein the charging wire supporting and conveying means holds down the charging wire with a force that is at least larger than a tension of the charging wire in a charging use area. 9. The charging wire pressing means for pressing the charging wire of at least the feeding pulley of the charging wire feeding means and the winding pulley portion of the charging wire winding means is provided. Charging device. 10. The charging device according to claim 6, wherein the charging wire supporting and conveying means also serves as the charging wire pressing means. 11. The charging device according to claim 6, wherein the support of said charging wire supporting and conveying means can be released. 12. The charging device according to claim 6, wherein at least a surface of a portion of the charging wire supporting and conveying means that is in contact with the charging wire is formed of an insulating elastic member. 13. A charging wire, comprising: a charging wire feeding pulley and a winding pulley.
A charging device comprising a charging wire stretched between both pulleys, wherein the charging wire is released in association with the removal of at least one of the feeding pulley and the winding pulley. 14. The charging device according to claim 13, wherein the cleaning member is set in association with attachment of at least one of the feeding pulley and the winding pulley. 15. A charging wire, comprising: a charging wire feeding pulley and a winding pulley.
In a charging device in which a charging wire is stretched between both pulleys, a control means for controlling the feeding of the charging wire from the feeding pulley in the winding pulley direction (first direction) and the charging wire winding 2. A charging device, characterized in that a control means for controlling the feeding from the feeding pulley in the feeding pulley direction (second direction) is provided. 16. The cleaning member for cleaning the charging wire is provided immediately after the charging wire of the feeding pulley is unwound and immediately before the charging wire of the winding pulley is wound. Charging device. 17. The feeding pulley and the winding pulley are driven on the same axis.
5. The charging device according to item 5. 18. A flag and a detection unit for detecting the flag outside the image forming unit of the charging wire are provided at the end portions of the charging wire of the feeding pulley and the winding pulley, and the detection unit detects the flag. The charging device according to claim 15, further comprising control means for controlling the feeding direction of the charging wire by detection. 19. The charging device according to claim 15, wherein the feeding pulley and the winding pulley are driven on the same shaft, and a cleaning member for cleaning the feeding wire for feeding and winding at the same time is provided. apparatus. 20. The charging device according to claim 15, wherein the feeding amount of the charging wire in the second direction within a fixed time is larger than the feeding amount of the charging wire in the first direction within a fixed time. . 21. A control means for winding up a charging wire having a length substantially equivalent to an image forming area outside during image formation after the feeding direction of the charging wire is changed from the first direction to the second direction. The charging device according to claim 15, wherein the charging device is provided.