JP2021177205A - Electrode cleaning device, electrifying device including the electrode cleaning device, and image forming apparatus - Google Patents

Abstract

To clean a discharge wire of an electrifier without damaging the wire as much as possible, while reducing manufacturing cost.SOLUTION: An electrode cleaning device cleans a discharge wire 221 of an electrifier 22, and comprises moving means that reciprocates a cleaning head 61 holding a cleaning pad that is in contact with a discharge electrode to clean the discharge electrode along the discharge wire 221. The moving means includes a first moving mechanism that manually moves the cleaning head 61 on a forward path, and a second moving mechanism that accumulates displacement of the cleaning head on the forward path as position energy in an energy accumulation mechanism 64, and moves the cleaning head 61 on a return path using the accumulated position energy.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to an electrode cleaning device for a discharge electrode in a charging device, a charging device provided with the electrode cleaning device, and an image forming device provided with the charging device.

In an electrophotographic image forming apparatus, after charging the surface of a photoconductor to a uniform potential with a charger, the surface of the photoconductor is exposed and scanned to form an electrostatic latent image, and toner is applied to the electrostatic latent image. The toner image is supplied to generate a toner image, the toner image is transferred onto the sheet, and then the toner image is thermally fixed by a fixing device.

As the above-mentioned charger, a corona charger is usually often used. The corona charger has a configuration in which a high voltage of several kV is applied to a discharge wire stretched in a shield case of the charger body to discharge the corona and charge the surface of the photoconductor.

In such a charger, when dust such as paper dust or a substance (discharge product) generated by corona discharge adheres to the discharge wire, that part does not discharge and uneven charging occurs, which causes image quality. It also causes deterioration.

Therefore, a device for cleaning the discharge wire (electrode cleaning device) has been conventionally proposed.

For example, a method in which a cleaning member such as a cleaning pad is brought into contact with the discharge wire, and the cleaning pad is manually reciprocated in the longitudinal direction along the tensioning direction of the discharge wire with a rod with a handle to clean the discharge wire (. Patent Document 1) has been proposed.

Further, a method of automatically cleaning the discharge wire by reciprocating the cleaning pad along the discharge wire by a screw feeding mechanism using a motor (Patent Document 2) has also been proposed.

JP-A-2010-85704 Japanese Unexamined Patent Publication No. 2008-134305

However, as in Patent Document 1, when the user manually moves the cleaning pad, the moving state of the cleaning pad tends to be unstable, and the time required for reciprocating cleaning becomes long. , There is a problem that the time for applying unnecessary tension to the discharge wire becomes long and the discharge wire is easily damaged.

Furthermore, normally, the maintenance door on the front of the device is opened to insert and remove the cleaning rod, but maintenance is performed with the rod protruding toward you without inadvertently pushing the rod to the end on the return trip. If the door is closed, the rod itself may bend due to collision with the protruding rod, or a force may be applied to the discharge wire in an unnatural direction via the cleaning pad to damage the discharge wire.

In this regard, Patent Document 2 discloses a configuration in which the cleaning pad is reciprocated by a screw feed mechanism driven by a motor. According to this configuration, the cleaning pad is stably moved without being stopped during the movement. At the same time, since the cleaning pad can be returned to the initial position by using a position sensor or the like, it is considered that the problem as in Patent Document 1 is unlikely to occur.

However, according to the technique of Patent Document 2, large-scale equipment such as a motor, a position sensor, and a screw feed mechanism is required, and a significant increase in manufacturing cost is unavoidable.

The present disclosure has been made in view of the above circumstances, and is an electrode cleaning capable of smoothly cleaning the discharge electrode while suppressing the manufacturing cost and reducing the risk of damage to the discharge electrode as much as possible. It is an object of the present invention to provide a charging device including the device and the electrode cleaning device, and an image forming device.

In order to achieve the above object, one aspect of the present disclosure is an electrode cleaning device for cleaning a discharge electrode stretched in a space inside a shield case of a charger, and a cleaning member for cleaning the discharge electrode. The cleaning head is provided with a moving means for reciprocating the cleaning head from the first position, which is the initial position, to the second position, which is the end position of the outward path, along the tensioning direction of the discharge electrode, and the moving means is a traction member. A first moving mechanism that manually moves the outward path of the cleaning head via the It is characterized by being provided with a second moving mechanism for moving the return route.

Further, in another aspect according to the present disclosure, the second moving mechanism includes an energy storage unit that stores the potential energy as elastic energy due to deformation of the elastic body.

Further, in another aspect according to the present disclosure, the elastic body is either a spring spring, a mainspring spring, or rubber.

Further, in another aspect of the present disclosure, the energy storage unit has a remaining force to move the cleaning head beyond the first position and further in the direction opposite to the second position on the return route. In the embodiment, the elastic energy is released.

Further, in another aspect according to the present disclosure, the elastic body is a spring, and the energy storage unit converts the amount of movement of the cleaning head in the outward path into the amount of winding of the spring. The second moving mechanism releases the elastic energy stored in the energy storage unit to move the return path of the cleaning head via the gear mechanism.

Further, in another aspect according to the present disclosure, the gear mechanism includes an input side rotary gear that is rotationally driven by movement of the cleaning head in the outward path, an output side rotary gear to which the Zenmai spring is connected, and the input side. The gear ratio switching unit is provided with a gear ratio switching unit for switching the gear ratio of the output side rotating gear to the rotating gear, and the gear ratio switching unit has a gear ratio when the cleaning head is moved on the return path and a gear ratio when the cleaning head is moved on the outward path. The gear ratio is switched so as to be larger than.

Further, in another aspect according to the present disclosure, the traction member in the first moving mechanism is a long rod that can be inserted and removed along the tensioning direction of the discharge electrode, and is in the longitudinal direction of the rod. A rack is formed along the above, and the input side rotating gear in the gear mechanism is a pinion that meshes with the rack.

Further, in another aspect according to the present disclosure, the first position and the second position are located outside the chargeable range of the charger in the stretching direction of the discharge electrode.

Further, in another aspect according to the present disclosure, the cleaning head is provided with a separating mechanism for separating the cleaning member from the discharge electrode when the cleaning head is in at least the first position of the first position and the second position.

Further, in another aspect according to the present disclosure, the cleaning head is attached to a sliding substrate slidably attached to the shield case of the charger in a direction parallel to the tensioning direction of the discharge electrode. The cleaning member is held so that the sliding substrate can be changed in posture between a first posture in which the cleaning member contacts the discharge electrode and a second posture in which the cleaning member is separated from the discharge electrode. The cleaning member holding body is provided, and when the cleaning head approaches the at least the first position, the protrusions arranged at the at least the first position of the cleaning member holding body are provided. The structure is such that the posture of the cleaning member holder is changed from the first posture to the second posture by abutting a part of the cleaning member holder.

Further, in another aspect according to the present disclosure, the cleaning member is separated from the discharge electrode while the cleaning head moves on the outward path, and the cleaning member is moved while the cleaning head moves on the return path. It is equipped with a contact state switching mechanism that contacts the discharge electrode.

Further, in another aspect according to the present disclosure, the cleaning head is slidably attached to the guide groove of the shield case of the charger in a direction parallel to the tensioning direction of the discharge electrode. A cleaning member holder that holds the cleaning member and is rotatably supported by the sliding substrate, and a lever member that is connected to a rotation support shaft of the cleaning member holder. The member is connected to the cleaning head via the lever member, and by manually pulling the traction member in the outward path direction, the lever member swings in the first direction, and the cleaning member holder However, in a state where the cleaning member is changed from the first posture in which the cleaning member is in contact with the discharge electrode to the second posture in which the cleaning member is separated from the discharge electrode, the cleaning head moves in the outward path and the cleaning head moves in the return path. The lever member swings in the second direction opposite to the first direction, and the cleaning member holder returns from the second posture to the first posture to bring the cleaning member into contact with the discharge electrode. As a result, it functions as the contact state switching mechanism.

Further, another aspect according to the present disclosure is a charging device having a discharge electrode and a cleaning means for cleaning the discharge electrode, and the electrode cleaning device is provided as the cleaning means. ..

Further, in another aspect of the present disclosure, the peripheral surface of the photoconductor is charged by a charging means, an electrostatic latent image is formed on the photoconductor by exposure scanning, and then developed with a developer to form a developer image. It is an image forming apparatus to be subjected to, and is characterized in that the above-mentioned charging apparatus is provided as the charging means.

According to the above configuration, the cleaning head having the cleaning member is manually moved on the outward route, and on the return route, the cleaning head is automatically moved by using the potential energy accumulated by the position change of the cleaning head on the outward route. Can be cleaned. As a result, unstable manual cleaning is limited to the outward route, reducing the risk of damaging the discharge electrode by half, and the return route can be automatically restored instead of manually, so there is a problem of accidentally forgetting to return the cleaning head. Does not occur. Further, since it is not necessary to use a motor or the like for moving the cleaning head, the manufacturing cost can be suppressed.

It is a schematic diagram for demonstrating the structure of the tandem type color copying machine which is an example of the image forming apparatus which concerns on embodiment of this disclosure. It is an overview perspective view of the charger in the said copying machine. It is the figure which looked at the said charger from the bottom side. It is a perspective view which shows an example of the structure of the cleaning head in the said charger. It is a perspective view which shows the state which the outer plate was removed when the cleaning head is located at the back end portion of a shield case. FIG. 5 is a diagram showing a state in which an outer plate is attached to a pad holder and an intermediate member in the state of FIG. 5 and a cleaning head is assembled. It is a figure which shows the structure of the energy storage mechanism for automatically moving a cleaning head in a return path in the said charger. (A) and (b) are diagrams for explaining the operation of the energy storage mechanism in the middle of the outward path and the middle of the return path of the cleaning head, respectively. (A) and (b) are diagrams for explaining a mechanism (cleaning pad separating mechanism) for separating the cleaning pad from the discharge wire when the cleaning head returns to the initial position in the charger, respectively. 9 is a diagram for explaining the positional relationship between the protrusion and the pad holder in the cleaning pad separation mechanism of FIG. 9 in the height direction (direction in which the rotation axis of the pad holder extends). It is a figure for demonstrating the main part of the electrode cleaning apparatus which concerns on the modification of this disclosure. (A) and (b) are diagrams for explaining the operation when the cleaning head in the electrode cleaning device of FIG. 11 moves on the outward path. (A) and (b) are diagrams for explaining the operation when the cleaning head in the electrode cleaning device of FIG. 11 moves on the return path. It is the schematic which shows the modification of the energy storage mechanism in the electrode cleaning apparatus which concerns on this disclosure. It is the schematic which shows another modification of the energy storage mechanism in the electrode cleaning apparatus which concerns on this disclosure.

Hereinafter, an example in which the charger provided with the electrode cleaning device according to the embodiment of the present disclosure is applied to a tandem type color copier (hereinafter, simply referred to as “copier”) will be described.

(1) Overall Configuration of Copier FIG. 1 is a schematic diagram for explaining the overall configuration of the copying machine 1 according to the present embodiment.

As shown in the figure, the copying machine 1 is roughly divided into an image reader unit R and a printer unit P.

<Image leader section>
The image reader unit R includes a scanner unit 10 that optically reads a document image and converts it into an image signal, and a document transport unit (ADF unit) 11 provided above the scanner unit 10.

The document transport unit 11 feeds the originals one by one from the document bundle set in the document feed tray 11a and conveys the originals to the reading position R1 on the platen glass 10a, and the scanner unit 10 displays the original image at the reading position R1. After being read, it is ejected onto the document ejection tray 11c.

The scanner unit 10 emits light from a linear light source 10b composed of an LED array or the like, and condenses the reflected light from a document passing through the reading position R1 on a line sensor 10d via a condensing lens group 10c.

The line sensor 10d is formed by arranging a plurality of CCDs (Charge Coupled Devices) in a straight line in a direction parallel to the main scanning direction, and converts the reflected light from the incident document into an electric signal in the printer unit P. Output to the control unit 50.

<Printer section>
The printer unit P includes an image forming unit 20, a paper feeding unit 30, a fixing unit 40, a control unit 50, and the like, and has been transmitted from another terminal via a network or a document image read by the image reader unit R. An image is formed on a sheet based on the image data.

The image forming unit 20 includes an intermediate transfer belt 26 that is orbitally driven in the arrow direction by a drive source (not shown), and process units 20Y, 20M, 20C, which are arranged along the vertical traveling surface of the intermediate transfer belt 26. It has 20K.

The process units 20Y, 20M, 20C, and 20K image toner images of each color of yellow (Y), magenta (M), cyan (C), and black (K), respectively.

Since all of these process units 20Y to 20K have the same configuration except for the color of the toner used, only the configuration of the process unit 20Y will be described as a representative.

The process unit 20Y is centered on the photoconductor drum 21Y, and a charger 22Y, an exposure device 23Y, a developer 24Y, and the like are arranged around the photoconductor drum 21Y.

The outer peripheral surface of the photoconductor drum 21Y is uniformly charged to a predetermined potential by the charger 22Y.

The exposure device 23Y modulates and drives the laser light source based on the image data acquired by the image reader unit R (or the image data included in the received print job) to expose the surface of the charged photoconductor drum 21Y. Scan. As a result, an electrostatic latent image is formed on the outer peripheral surface of the photoconductor drum 21Y.

The electrostatic latent image is developed with yellow toner by the developer 24Y, and the developed toner image is primary transferred onto the intermediate transfer belt 26 by the voltage applied to the primary transfer roller 25Y.

Transferring M-color, C-color, and K-color toner images formed by shifting for a predetermined time on the photoconductor drums of the other process units 20M, 20C, and 20K overlaid on the same position on the intermediate transfer belt 26. To form a color toner image.

The toner image transferred on the intermediate transfer belt 26 is conveyed to the secondary transfer position facing the secondary transfer roller 27 by the orbiting motion of the intermediate transfer belt 26.

On the other hand, the paper feed unit 30 has the paper feed cassettes 31 to 33, feeds out the sheet from the designated paper feed cassette, transfers the sheet to the secondary transfer position at the timing by the resist roller 34, and transfers the sheet to the secondary transfer position on the intermediate transfer belt 26. The toner image of is secondarily transferred onto the sheet.

The sheet on which the toner image is transferred passes through the nip portion formed by the heating roller 41 and the pressure roller 42 of the fixing portion 40, is thermally fixed, and then is placed on the discharge tray 29 via the discharge roller 28. Is discharged to.

(2) Configuration of Charger Next, the configuration of the chargers 22Y to 22K will be described with reference to the drawings. In the present embodiment, the chargers 22Y to 22K in each process unit 20M to 20K all have the same configuration. Therefore, the subscripts Y to K will be omitted below.

Further, for convenience of explanation, the vertical direction merely indicates the relative vertical relationship in each drawing, and does not indicate the absolute vertical relationship.

FIG. 2 is an overall external perspective view of the charger 22 as viewed from above (the side having the discharge opening 220 facing the peripheral surface of the photoconductor drum 21), and the longitudinal direction (Y-axis direction) thereof is , It is parallel to the rotation axis of the photoconductor drum 21 (FIG. 1), and the lower left side in the drawing is the front side (front side) of the copying machine 1.

The main body of the charger 22 is a shield case 222 made of a metal such as aluminum, end covers 223 and 224 made of an insulating resin material attached to both ends in the longitudinal direction thereof, and end covers 223 and ends. A discharge wire 221 stretched between the portion cover 224 and the charger 22 in a direction parallel to the longitudinal direction (Y-axis direction) of the charger 22 is included.

The discharge wire 221 is made of, for example, a tungsten wire plated with gold or the like, and is stretched between the end cover 223 and the end cover 224, and at one end of the discharge wire 221 via a tension spring (not shown). By being held by the end cover 223 (or 224), a constant tension is applied to the discharge wire 221.

A discharge opening 220 is formed between the end cover 223 and the end cover 224, exposing the discharge wire 221. The length L0 (length in the longitudinal direction of the chargeable range) of the discharge opening 220 in the longitudinal direction (Y-axis direction) is equal to the width of the axially charged region of the photoconductor drum 21 to be charged. Set.

Further, the end cover 224 is provided with an extension portion 225 extending toward the front side.

The charger 22 further includes an electrode cleaning device 60 for cleaning the discharge wire 221. The electrode cleaning device 60 is connected to the cleaning head 61 (in FIG. 2, a state of waiting at a position (initial position) under the end cover 223) and the cleaning head 61, and is connected to the cleaning head 61 in the Y-axis direction. An operation rod 62 extending in parallel and an energy storage mechanism 64 for accumulating energy when the operation rod 62 is manually pulled toward the front side (direction of arrow A) and returning the cleaning head 61 to the initial position are provided. Be prepared.

(3) Electrode Cleaning Device (3-1) Cleaning Head FIG. 3 is a bottom view of the charger 22 of FIG. 2 when viewed from below.

As shown in the figure, a guide groove 226 extending in the longitudinal direction (Y-axis direction) of the discharge opening 222 is formed on the bottom surface of the shield case 222, and the cleaning head 61 is formed along the guide groove 226. It is possible to slide from the initial position P11 to the outward end position (turning position) P12.

The initial position P11 and the outward end position P12 are arranged outside the discharge opening 220 having a length L0 in the longitudinal direction, respectively.

In the present embodiment, the distance L1 between the initial positions P11 and P1 and the distance L2 between the outbound terminal positions P12 and P2 are the cleaning head 61 when the cleaning head 61 is located at the position P11 or the position P12. The cleaning pads 6113 and 6114 (see FIG. 4) are at least a distance that is not within the chargeable range between positions P1 and P2 in a plan view, and at least the portion within the chargeable range of the discharge wire 221 is cleaned. The distance is set so that the pair of cleaning pads 6113 and 6114 can be reliably cleaned by contacting the discharge wires 221 by the reciprocating movement between the positions P11 and P12 of the head 61.

FIG. 4 is a perspective view showing a configuration when only the cleaning head 61 is viewed from diagonally above the left side of FIG.

As shown in the figure, the cleaning head 61 is formed by combining a pad holder 611, an intermediate member 612, and an outer plate 613.

A rotating shaft 6115 is erected on the upper surface of the main body 6110 of the pad holding body 611 (see FIG. 5), and the rotating shaft 6115 penetrates the shaft holes of the intermediate member 612 and the outer plate 613, and the tip thereof Projects from the surface of the outer plate 613, an E-ring 614 for retaining the retaining member is fitted into the peripheral groove 6115a of the rotating shaft 6115, and the pad holder 611 is rotatably supported by the intermediate member 612 and the outer plate 613. It is composed.

As shown in FIG. 4, two pad holding portions 6111 are placed on the lower surface of the main body portion 6110 of the pad holding body 611 at positions symmetrical with respect to the axis of the rotating shaft 6115 (see FIG. 9A). , 6112 are erected, and cleaning pads 6113 and 6114 made of an elastic material such as rubber or sponge are attached as cleaning members at positions where they come into contact with the respective discharge wires 221 with an adhesive or the like.

Further, the tip end portion of the operating rod 62 is fitted and fixed in the fitting hole 6132 of the rod holding portion 6131 provided on the upper surface of the outer plate 613 (see FIG. 6).

FIG. 5 is a perspective view showing a state in which the outer plate 613 is removed when the cleaning head 61 is located at the back end portion (initial position P11) of the shield case 222.

As shown in FIG. 9A, both ends of the intermediate member 612 in the X-axis direction are located on the back sides of the inner edges 226a and 226b of the guide groove 226 of the shield case 222, and each end is the inner surface of the shield case 222. The intermediate member 612 can move in the shield case 222 in the Y-axis direction while maintaining its posture.

Returning to FIG. 5, an engaging pin 6116 and a shaft support pin 6117 are erected on the upper surface of the main body portion 6110 of the pad holder 611, and the frame 6118 is rotatably attached to the shaft support pin 6117. ..

A boss portion 6121 is formed in the shaft hole of the intermediate member 612. The position of the upper surface of the boss portion 6121 is slightly higher than the position of the apex of the engaging pin 6116 and the shaft support pin 6117.

As shown in FIG. 5, the width of the guide groove 226 in the X-axis direction is wide at the initial position, which allows the pad holder 611 to rotate and discharges the cleaning pads 6113 and 6114. This is for releasing the contact state with the wire 221. Details will be described later.

FIG. 6 shows a state in which the end portion of the rotating shaft 6115 in FIG. 5 is inserted into the shaft hole of the outer plate 613, the outer plate 613 is mounted on the intermediate member 612, and the E-ring 614 is attached. As a result, the outer plate 613 and the intermediate member 612 sandwich the inner edge portions 226a and 226b of the guide groove 226 from above and below, and the cleaning head 61 is slidably held along the guide groove 226 (with the intermediate member 612). Together with the outer plate 613, it becomes a "sliding substrate").

The tip of the operating rod 62 is fitted and fixed to the rod holding portion 6131 of the cleaning head 61. Although not shown in particular, the E-ring is attached to the portion of the tip of the operating rod 62 that protrudes from the rod holding portion 6131 so that the operating rod 62 does not come off from the rod holding portion 6131 even if the operating rod 62 is pulled strongly. desirable.

In the present embodiment, the user picks the knob portion 63 formed at the front end of the operation rod 62 and pulls it out toward the front (direction of arrow A in FIG. 2) to pull the cleaning head 61 to the initial position (P11 in FIG. 3). ) To the turning position (outward route end position P12 in FIG. 3) by the end cover 224 on the front side (outward route), and the position change at this time is stored in the energy storage mechanism 64 as potential energy and picked by the user. When the unit 63 is released, the cleaning head 61 is automatically returned to the initial position P11 by the potential energy stored in the energy storage mechanism 64.

(3-2) Energy Storage Mechanism (a) Basic Configuration FIG. 7 is a perspective view of the energy storage mechanism 64 according to the present embodiment when viewed from diagonally above left of FIG. 3, so that the internal structure can be easily understood. , A part of the side surface and the upper surface of the housing 641 of the energy storage mechanism 64 are removed.

The housing 641 of the energy storage mechanism 64 is attached to a frame (or end cover 224) (not shown) in the apparatus, and the energy storage mechanism 64 is attached to the movement of the operation rod 62 in the longitudinal direction. It is in a relatively fixed state.

A rack 621 is formed on the energy storage mechanism 64 side of the operation rod 62 along the longitudinal direction of the operation rod 62. The energy storage mechanism 64 includes a pinion 642 that meshes with the rack 621, a movable gear 643, a first intermediate gear 644, a second intermediate gear 645, a two-stage gear 646, and a mainspring 647 (second moving mechanism).

The two-stage gear 646 is formed by stacking a small-diameter gear 6461 and a large-diameter gear 6462 on top of each other and fixing them to a shaft 6443. Further, the central end of the mainspring 647 is fixed to the shaft 6443, and the outer end 6471 is fixed to the pin 6472 erected in the housing 641.

The first intermediate gear 644 meshes with the small diameter gear 6461, and the second intermediate gear 645 meshes with the large diameter gear 6462.

Further, the shaft 6432 of the movable gear 643 has a first position in which the movable gear 643 meshes with the first intermediate gear 644 and a second position in which the movable gear 643 meshes with the second intermediate gear 645 through the elongated hole 6431 of the housing 641. It is supported to be movable between and.

The shaft 6432 is urged toward the second position by a tension spring 6433 whose one end is locked to the locking portion 6433a (see FIG. 8A) of the housing 641.

The tip of the operation rod 62 is connected to the rod holding portion 6131 of the cleaning head 61 (FIG. 6), and the intermediate portion thereof is held by the sliding holding portion 2241 provided on the end cover 224. As a result, it is held so that it can be inserted and removed along the longitudinal direction of the charger 22 (the direction in which the discharge wire 221 is stretched) (first moving mechanism).

(A) Operation explanation FIGS. 8 (a) and 8 (b) are diagrams showing the operation of the energy storage mechanism 64 in the outward route and the return route, respectively.

First, the user opens the maintenance door (not shown) on the front surface of the device, picks the knob portion 63 (FIG. 3), pulls out the operation rod 62 toward the front side (direction of arrow A), and pulls out the cleaning head. The 61 is moved from the initial position P11 to the outward end position (turning position) P12 (see FIG. 3) (outward route).

At this time, as shown in FIG. 8A, as the operation rod 62 moves in the A direction, the pinion 642 meshing with the rack 621 rotates clockwise, whereby the shaft 6432 of the movable gear 643 becomes , It is moved in the direction of the first intermediate gear 644 against the urging force of the tension spring 6433 and meshes with the first intermediate gear 644.

The first intermediate gear 644 meshes with the small diameter gear 6461 of the two-stage gear 646 to rotate the shaft 6436 counterclockwise and wind the mainspring 647 (FIG. 7). That is, the position change in the manual movement of the cleaning head 61 on the outward path is converted into the elastic energy of the mainspring 647 and accumulated.

At this time, the winding amount of the mainspring 647 is the gear ratio of the pinion 642, which is the input side gear, to the small diameter gear 6461 on the output side (= (the number of teeth of the output side gear) / (the number of teeth of the input side gear)). Determined by (1st gear ratio).

When the user pulls out the cleaning head 61 to the front end position P12 of the outward path and then releases the knob portion 63, the elastic energy of the spring 647 is released, and as shown in FIG. 8B, the shaft 6463 is moved. Rotate clockwise.

Since the pinion 642 is stopped immediately before this, the movable gear 643 is moved to the second position where it meshes with the second intermediate gear 645 by the urging force of the tension spring 6433, and the large-diameter gear of the two-stage gear 646. The clockwise rotational force of 6462 causes the pinion 642 to rotate counterclockwise via the second intermediate gear 645 and the movable gear 643, resulting in movement of the rack 621 in the B direction, which causes the cleaning head 61 to be in its initial position. Move the return route toward P11.

On the outward trip, the rotational force of the pinion 642 is finally transmitted to the small-diameter gear 6461 (first gear ratio), and on the contrary, on the return trip, the pinion 642 is rotated by the rotational force of the large-diameter gear 6462 (first gear ratio). 2 gear ratio).

By moving the movable gear 643 in this way, the gear ratio of the output gear to the gear of the input shaft can be switched, so that the movable gear 643 functions as a “gear ratio switching unit”.

Since the outbound and inbound routes are the same distance, the number of rotations of the pinion 642 required for each movement is the same, but in the outbound and inbound routes, the final gear (output side gear) with respect to the pinion 642 (input side gear) Since the gear ratios are different (first gear ratio <second gear ratio), the number of rotations of the shaft 6436 required for the return movement is less than the number of rotations for accumulating the elastic energy of the outward movement.

Therefore, when the cleaning head 61 advances on the return path and reaches the initial position, the spring 647 does not completely release the accumulated elastic energy, and a spare force for further moving the cleaning head 61 in the return path remains. This ensures that the cleaning head 61 is completely returned to the initial position P11.

However, in this case, every time the cleaning head 61 is reciprocated, elastic energy that is not gradually released is accumulated in the mainspring 647, and eventually the mainspring 647 is wound off and moved to the outbound terminal position P12 on the outbound route. If the operation rod 62 is forcibly pulled, the spring 647 may be damaged.

Therefore, in the present embodiment, the tooth missing portion 6211 is provided in the portion corresponding to the pinion 642 of the rack 621 when the cleaning head 61 returns to the initial position (see FIG. 8B). As a result, after the cleaning head 61 is surely returned to the initial position, the pinion 642 is idled at the missing tooth portion 6211, so that all the elastic energy remaining in the mainspring 647 can be released and reset. As described above, there is no risk of the spring 647 being damaged.

Alternatively, the inner end of the mainspring 647 may be coupled to the shaft 6464 via a torque limiter. This also makes it possible to avoid the possibility that the spring 647 is wound too much and damaged.

In this way, the cleaning head 61 is configured to automatically move to the initial position P11 on the return route by the elastic energy stored in the energy storage mechanism 64 on the outward route. Compared to the unstable manual movement, the risk of causing unnecessary damage to the discharge wire 221 is halved, and the cleaning head 61 automatically returns to the initial position when the knob 63 is released. Therefore, there is no trouble that the operation rod 62 is inadvertently forgotten to be returned and the maintenance door is closed. In addition, the manufacturing cost can be significantly reduced as compared with the case where the cleaning head is moved by driving the motor.

(3-3) Cleaning Pad Separation Mechanism Cleaning of the discharge wire 221 is not performed very frequently, and the cleaning pads 6113 and 6114 come into contact with the discharge wire 221 even while the cleaning head 61 is waiting at the initial position. If this is done, unnecessary tension will be constantly applied to the discharge wire 221 and the life of the discharge wire 221 may be shortened.

Therefore, in the present embodiment, when the cleaning head 61 returns to the initial position P11, the pad holder 611 rotates around the rotation shaft 6115, and the cleaning pads 6113, 6114 and the discharge wire 221 are automatically in contact with each other. Is configured to be released (cleaning pad separation mechanism).

FIG. 9A is a plan view of the cleaning head 61 when it approaches the end cover 223 on the return route when viewed from the discharge opening 220 side.

At this stage, the top 6118 (see FIG. 5) arranged on the back surface of the pad holder 611 comes into contact with the straight portion (the portion extending parallel to the discharge wire 221) of the inner edge portion 226b of the guide groove 226, and also Cleaning because the engaging pin 6116 (see FIG. 5) erected on the back surface of the pad holder 611 is in contact with the straight portion (the portion extending parallel to the discharge wire 221) of the inner edge portion 226a of the guide groove 226. The posture of the pad holder 611 is maintained while the contact pressure between the pads 6113 and 6114 and the discharge wire 221 remains constant.

When the cleaning head 61 advances further toward the initial position P11, the tip of the protrusion 2231 provided on the end cover 223 is located below the attachment position of the cleaning pad 6114 of the pad holding portion 6112 (root). Contact.

When the guide groove 226 is further advanced in the B direction from this position, the inner edge portions 226a and 226b of the guide groove 226 are retracted to the inner edge portion 226c and the inner edge portion 226d, respectively, and the width of the guide groove 226 is widened. The pin 6116 is released from the restraint of the guide groove 226.

After that, the pad holding portion 6112 is given a component force to rotate counterclockwise by the tapered portion 2231a of the protruding portion 2231, and the pad holding body 611 cleans the cleaning pad 6113 as shown in FIG. 9B. The pad 6114 rotates in the direction away from the discharge wire 221 and the rotation of the pad holder 611 stops in a state where the linear side side portion 6110a of the main body portion 6110 is in contact with the flat portion 2232 of the end cover 223. , As it is, wait until the next cleaning operation is executed.

FIG. 10 describes the positional relationship between the protrusion 2231 provided on the end cover 223 and the pad holder 611 in the Z-axis direction (direction of the rotation axis 6115 of the pad holder 611) in FIG. 9B. Therefore, it is a side view of the vicinity of the end cover 223 when the shield case 222 is removed.

As shown in the figure, the protrusions 2231 provided on the end cover 223 are the upper surface of the main body 6110 of the pad holding body 611, and the cleaning pads 6113 and 6114 of the pad holdings 6111 and 6112 in the Z-axis direction. It is provided so as to project in a direction parallel to the Y-axis direction between the mounting position and the mounting position.

Returning to FIG. 9B, when the operation rod 62 is pulled out through the knob portion 63 in the next cleaning operation, the operation opposite to the above is executed. That is, the contact between the pad holding portion 6112 and the protrusion 2231 is released, the frame 6118 is brought into contact with the tapered portion 226e at the inner edge of the guide groove 226, and the pad holding body 611 is rotated clockwise. NS.

After that, the frame 6118 abuts on the inner edge portion 226b of the guide groove 226, and the engaging pin 6116 abuts on the inner edge portion 226a. The contact position is restored and the discharge wire 221 is cleaned.

At the initial position P11, in addition to the configuration in which the cleaning pads 6113 and 6114 are separated from the discharge wire 221 as described above, the cleaning pad separating mechanism similar to the above is also generated when the cleaning head 61 reaches the outward path end position P12. May be provided.

In this case, the dust and discharge products scraped off on the outward route are once separated from the discharge wire 221 to drop the cleaning pads 6113 and 6114 from the cleaning pads 6113 and 6114, and the dust and discharge products are dropped from the cleaning pads 6113 and 6114 on the return route. There is an advantage that it is possible to suppress the occurrence of inconvenience such as leaving the dust and the like collected in the above on the discharge wire 221.

In this example, the protrusion 2231 comes into contact with the base of the pad holding portion 6112 of the pad holding body 611, and the pad holding body 611 is rotated counterclockwise as shown in FIG. 9B. However, if the portion where the protrusion 2231 abuts gives a force to rotate (change the posture) the pad holder 611 so that the cleaning pads 6113 and 6114 are separated from the discharge wire 221 as described above, the pad It may be brought into contact with other suitable parts of the holder 611.

<Modification example>
Although the embodiment according to one aspect of the present disclosure has been described above, it goes without saying that the present invention is not limited to the above-described embodiment, and the following modifications can be considered.

(1) In the above embodiment, the cleaning pads 6113 and 6114 are brought into contact with the discharge wire 221 on both the outward path and the return path of the operation rod 62, the cleaning head 61 is manually moved on the outward path, and the energy storage mechanism is moved on the return path. The discharge wire 221 was cleaned on the outward route and the return route by automatically recovering using the elastic energy of 64.

As a result, the risk of damaging the discharge wire 221 can be halved as compared with the case where the reciprocating movement of the conventional cleaning head 61 is manually operated.

In this modification, this is further improved, and in the manual outbound route, only the cleaning head 61 is moved without bringing the cleaning pads 6113 and 6114 into contact with the discharge wire 221. It is characterized by having a contact state switching mechanism that switches to the contact state and cleans the discharge wire 221 only on the return path that automatically moves by the elastic energy stored in the energy storage mechanism 64 on the outward path. ..

FIG. 11 is a perspective view showing a connected state of the cleaning head 61 and the operating rod 62, which are the main parts of the contact state switching mechanism in this modified example, and the outer plate 613 (see FIG. 4 and the like) is shown for convenience of explanation. It is omitted.

Two pad holding portions 6111 and 6112 are erected on the lower surface of the main body portion 6110 of the pad holding body 611 of the cleaning head 61 at positions symmetrical with respect to the center of rotation, and the cleaning pads 6113 and 6114 are respectively erected. It will be pasted.

Further, two regulation pins 6119a and 6119b are erected on the upper surface of the main body 6110, and regulate the rotation angle around the rotation shaft 6115 of the pad holder 611 on the outward path and the return path, respectively.

A plate-shaped lever member 6140 is formed above the rotating shaft 6115, and a through hole 6141 is formed in the lever member 6140.

On the other hand, a large-diameter head 622 is attached to the tip of the operating rod 62 via a reduced-diameter portion 623, and the reduced-diameter portion 623 is loosely inserted into the through hole 6141 of the lever member 6140.

Both sides of the plate-shaped lever member 6140 are provided with boss portions 6142 and 6143 that communicate with the through hole 6141 (the boss portion 6143 is hidden behind the lever member 6140 in FIG. 11 and cannot be seen). )reference).

As shown in the plan view of FIG. 12A, each of the boss portions 6142 and 6143 has a shape in which the top surface is cut diagonally, whereby the cleaning head 61 is formed according to the moving direction of the operation rod 62. The surface 62a to which the reduced diameter portion 623 of the operation rod 62 is connected, or the surface 622a to which the reduced diameter portion 623 of the head 622 is connected, and the tops of the boss portions 6142 and 6143, respectively, in a state of being rotated by a predetermined angle. The surface is in close contact with the surface, and the operability and stability when the cleaning head 61 is reciprocated are improved.

The axial length L3 of the reduced diameter portion 623 and the inner diameter of the through hole 6141 of the lever member 6140 are such that the operation rod 62 is in the A direction (outward route: FIG. 12 (a)) and the B direction (return route: FIG. 13 (a), respectively. )) Is set to a size that allows a predetermined amount of rotation of the pad holder 611 when moving.

FIG. 12A is a plan view of the cleaning head 61 during outward movement when viewed from the bottom surface side. In this drawing, the outer plate 613 is omitted so that the operation in the present modification can be easily understood. There is.

In FIG. 12A, when the user pulls the operation rod 62 in the A direction on the outward path, the lever member 6140 also swings in the A direction, so that the pad holder 611 rotates counterclockwise (counterclockwise) in FIG. 12A. Rotating clockwise), the regulation pin 6119a erected on the main body portion 6110 of the pad holder 611 is moved in the A direction while maintaining the posture of being in contact with the inner edge portion 226b of the guide groove 226.

FIG. 12B is a plan view of the state in FIG. 12A as viewed from the upper surface side (discharge opening 220 side) of the charger 22.

As shown in FIG. 12B, when the main body 6110 of the pad holder 611 is in this rotational position, the pad holders 6111 and 6112 are moving in the direction away from the discharge wire 221 and the cleaning pad 6113. , 6114 are separated from the discharge wire 221.

As a result, when the outbound route is manually moved, the cleaning pads 6113 and 6114 do not come into contact with the discharge wire 221 and the cleaning operation is not executed. Therefore, the discharge wire 221 is not damaged by the manual operation.

On the other hand, FIG. 13A is a view when the cleaning head 61 during the return route movement is viewed from the bottom surface side, and the illustration of the outer plate 613 is omitted in this figure as well so that the operation in this modification can be easily understood. ing.

As described above, in the return path, the operating rod 62 moves in the B direction of FIG. 13A due to the elastic energy stored in the energy storage mechanism 64, whereby the lever member 6140 also swings in the B direction. Therefore, the main body portion 6110 of the pad holder 611 rotates clockwise (clockwise), the regulation pin 6119b comes into contact with the inner edge portion 226b of the guide groove 226, and cleaning is performed in a state where further rotation is restricted. The head 61 is moved in the B direction.

13 (b) is a plan view of the state in FIG. 13 (a) when viewed from the upper surface side of the charger 22.

As shown in FIG. 13B, when the main body portion 6110 is in this rotational posture, the pad holding portions 6111 and 6112 move in the direction close to the discharge wire 221 and the cleaning pads 6113 and 6114 are constant. It is in contact with the discharge wire 221 by pressure contact force.

That is, in this modification, the cleaning pads 6113 and 6114 can be prevented from contacting the discharge wire 221 when the outward path is manually moved, and inconveniences associated with the manual operation (movement speed and pull-out direction become unstable). Therefore, it is possible to avoid damaging the discharge wire 221 and liable to cause uneven cleaning, etc.), and on the return route, the energy storage mechanism with the cleaning pads 6113 and 6114 in contact with the discharge wire 221. Since it moves stably due to the elastic energy stored in 64, uneven cleaning does not occur, and the discharge wire 221 can be reliably cleaned.

In the above embodiment, the tip of the operating rod 62 is fixed to the rod holding portion 6131 of the outer plate 613, but in this modification, for example, the operating rod 62 penetrates the rod holding portion 6131. The reduced diameter portion 623 provided at the tip of the operating rod 62 is loosely inserted into the through hole 6141 of the lever member 6140 as described above to respond to the insertion / removal movement of the operating rod 62. Therefore, the lever member 6140 can be configured to swing.

(2) Modification Example of Energy Storage Mechanism In the above embodiment, the energy storage mechanism 64 is positioned on the outward path of the cleaning head 61 via a gear mechanism such as a pinion 642 that meshes with a rack 621 provided on the operation rod 62. The change is converted into elastic energy (potential energy due to the elastic force of the spring 647) and stored, but the energy storage mechanism according to the present disclosure is not limited to such a configuration.

For example, as shown in FIG. 14, a tension spring 650 is provided between the spring locking portion 2233 and the spring locking portion 6133 of the outer plate 613 of the cleaning head 61 on the end cover 223 on the initial position side of the charger 22. You may try to hang it up.

In this case, even if the cleaning head 61 moves from the initial position P11 to the outward end position P12, a tension spring 650 of an appropriate size that maintains the restoring force without plastic deformation is used.

Further, the size of the tension spring 650 and / or the locking position of the spring is set so that the tension spring 650 is slightly extended from its natural length even when the cleaning head 61 is in the initial position P11. desirable. As a result, the cleaning head 61 can be reliably returned to the initial position on the return route.

If it is a spring spring, a compression spring may be used instead of the tension spring. Also, other elastic materials such as elongated strip-shaped or rope-shaped rubber can be used.

Further, the energy storage mechanism may convert the position change of the cleaning head 61 on the outward path into potential energy due to gravity instead of potential energy due to elastic force and store it.

FIG. 15 is a schematic side view of the charger 22 showing a modified example in this case.

As shown in the figure, a moving force larger than the static friction between the cleaning head 61 and the guide groove 226 of the shield case 222 is applied to return the cleaning head 61 from the outward end position P12 to the initial position P11. The weight 663 of the weight required for the above is hung by the wire 662, and the other end of the wire 662 is fastened to the wire fastening portion 6134 of the cleaning head 61 via the pulley 661.

The length of the wire 662 from the pulley 661 to the weight 663 is set to be longer than the moving distance of the cleaning head 61 on the outward route. In order to prevent the weight 663 from shaking due to the vibration of the copying machine 1, for example, a guide rod extending in the vertical direction is installed in the apparatus of the copying machine 1, and the weight 663 is configured to move up and down along the guide rod. You may.

In the modified examples shown in FIGS. 14 and 15, it is not necessary to form the rack 621. Therefore, instead of the operating rod 62 as a member (traction member) for pulling out the cleaning head 61 toward the front on the outward route, For example, it is possible to use a wire or the like.

(3) In the energy storage mechanism 64 in the above embodiment, the gear ratio between the input side gear and the output side gear in the gear mechanism is made different depending on the movable gear 643 between the outward path and the return path, but the outward path and the return path are different. If the cleaning head 61 is assembled so that the mainspring 647 is slightly involved when the cleaning head 61 is in the initial position P11 without switching the gear ratio, the spring will return on the return route unless the elasticity of the mainspring deteriorates. It is considered that the cleaning head 61 can be reliably returned to the initial position P11.

(4) A grid electrode may be arranged at the discharge opening of the charger 22 and a predetermined voltage may be applied to the grid electrode so that the electrocharged position becomes an optimum value.

(5) In the above embodiment, only one discharge wire is provided, but two or more discharge wires 221 are stretched in parallel in the shield case so that the cleaning pad is in contact with each of them. The cleaning head 61 may be configured.

Further, instead of the case where the discharge electrode is a wire as described above, for example, a thin band-shaped discharge electrode whose edge on the discharge side is processed into a saw blade shape may be used.

(6) In the above embodiment, the cleaning pad has been described as an example of the cleaning member, but the member is not limited to the cleaning pad as long as it is a member that can be cleaned by contacting the discharge wire.

(7) In the above embodiment, the charger 22 is used to charge the peripheral surface of the photoconductor drum 21, but for example, to remove the potential remaining on the peripheral surface of the photoconductor drum 21 in advance. It can also be used as a static eliminator.

(8) In the above embodiment, the tandem type color copier has been described, but the present invention is not limited to this, and any image forming apparatus including a charger may be used as a fax machine or a printer-dedicated machine. Further, a monochrome printer may be used instead of a color printer.

≪Supplement≫
The electrode cleaning device, the charging device, and the image forming device according to the present invention have been described above based on the embodiments and modifications, but the present invention is not limited to the above embodiments and modifications. .. By arbitrarily combining the components and functions in the embodiment and the modified example, the form obtained by applying various modifications that a person skilled in the art can think of, and the embodiment and the modified example without departing from the spirit of the present invention. The realized form is also included in the present invention.

The present invention is suitable as a technique for cleaning the discharge electrode of a charging device in an electrophotographic image forming device.

1 Copier 10 Scanner unit 20 Printer unit 30 Paper feed unit 40 Fixing unit 60 Electrode cleaning device 61 Cleaning head 62 Operation rod 64 Energy storage mechanism (energy storage unit)
220 Discharge opening 221 Discharge wire 222 Shield case 223, 224 End cover 226 Guide groove 226a to 226d Inner edge of guide groove 611 Pad holder (cleaning member holder)
612 Intermediate member 613 Outer plate 621 Rack 642 Pinion 643 Movable gear 644 1st intermediate gear 645 2nd intermediate gear 646 2-stage gear 2231 Protrusion 6111, 6112 Pad holding part 6113, 6114 Cleaning pad (cleaning member)
6115 Rotating shaft 6116 Engagement pin 6117 Shaft support pin 6118 Top 6119a, 6119b Regulation pin 6140 Lever member

Claims (14)

An electrode cleaning device that cleans the discharge electrodes stretched in the space inside the shield case of the charger.
A moving means for reciprocating a cleaning head having a cleaning member for cleaning the discharge electrode from the first position, which is the initial position, to the second position, which is the end position of the outward path, along the tensioning direction of the discharge electrode. Prepare,
The means of transportation is
A first moving mechanism that manually moves the outward path of the cleaning head via a traction member, and
A second moving mechanism that stores a change in the position of the cleaning head on the outward path as potential energy and uses the stored potential energy to move the return path of the cleaning head.
An electrode cleaning device characterized by being provided. The electrode cleaning device according to claim 1, wherein the second moving mechanism includes an energy storage unit that stores the potential energy as elastic energy due to deformation of the elastic body. The electrode cleaning device according to claim 2, wherein the elastic body is any one of a spring spring, a mainspring spring, and rubber. The energy storage unit releases the elastic energy in such a manner that there is a remaining force for moving the cleaning head beyond the first position and further in the direction opposite to the second position on the return path. The electrode cleaning device according to claim 2 or 3, wherein the electrode cleaning device is characterized. The elastic body is a spring and is
The energy storage unit
A gear mechanism for converting the amount of movement of the cleaning head on the outward path into the amount of winding of the mainspring spring is provided.
The electrode according to claim 2 or 3, wherein the second moving mechanism releases the elastic energy stored in the energy storage unit to move the return path of the cleaning head via the gear mechanism. Cleaning device. The gear mechanism
The input side rotary gear that is rotationally driven by the movement of the cleaning head on the outward path,
The output side rotary gear to which the mainspring is connected and
A gear ratio switching unit for switching the gear ratio of the output side rotary gear to the input side rotary gear is provided.
The fifth aspect of claim 5, wherein the gear ratio switching unit switches the gear ratio so that the gear ratio when the cleaning head moves in the return path is larger than the gear ratio when the cleaning head moves in the outward path. Electrode cleaning device. The traction member in the first moving mechanism is a long rod that is removably arranged along the tensioning direction of the discharge electrode.
The electrode cleaning device according to claim 6, wherein a rack is formed along the longitudinal direction of the rod, and the input side rotating gear in the gear mechanism is a pinion that meshes with the rack. The first position and the second position are located outside the chargeable range of the charger in the stretching direction of the discharge electrode, according to any one of claims 1 to 7. Electrode cleaning device. The electrode according to claim 8, further comprising a separating mechanism for separating the cleaning member from the discharge electrode when the cleaning head is in at least the first position of the first position and the second position. Cleaning device. The cleaning head
A sliding substrate that is slidably attached to the shield case of the charger in a direction parallel to the tensioning direction of the discharge electrode.
The cleaning member is held so that the sliding substrate can be changed in posture between a first posture in which the cleaning member contacts the discharge electrode and a second posture in which the cleaning member is separated from the discharge electrode. Cleaning member holder and
With
In the separation mechanism, when the cleaning head approaches the at least the first position, the protrusion arranged at the at least the first position comes into contact with a part of the cleaning member holding body to hold the cleaning member. The electrode cleaning device according to claim 9, wherein the posture of the body is changed from the first posture to the second posture. While the cleaning head moves on the outward path, the cleaning member is separated from the discharge electrode, and while the cleaning head moves on the return path, a contact state switching mechanism for bringing the cleaning member into contact with the discharge electrode is provided. The electrode cleaning device according to claim 1, further comprising. The cleaning head
A sliding substrate that is slidably attached to the guide groove of the shield case of the charger in a direction parallel to the tensioning direction of the discharge electrode.
A cleaning member holder that holds the cleaning member and is rotatably supported by the sliding substrate.
A lever member connected to a rotary support shaft of the cleaning member holder and
With
The traction member is connected to the cleaning head via the lever member, and by manually pulling the traction member in the outward path direction, the lever member swings in the first direction and the cleaning member. The cleaning head moves on the outward path in a state where the holding body is changed from the first posture in which the cleaning member is in contact with the discharge electrode to the second posture in which the cleaning member is separated from the discharge electrode.
When the cleaning head moves on the return path, the lever member swings in the second direction opposite to the first direction, and the cleaning member holder returns from the second posture to the first posture to remove the cleaning member. The electrode cleaning device according to claim 11, wherein the electrode cleaning device functions as the contact state switching mechanism by being brought into contact with the discharge electrode. A charging device having a discharge electrode and a cleaning means for cleaning the discharge electrode, characterized in that the electrode cleaning device according to any one of claims 1 to 12 is provided as the cleaning means. Charging device. An image forming apparatus that charges the peripheral surface of a photoconductor by a charging means, forms an electrostatic latent image on the photoconductor by exposure scanning, and then develops the photoconductor with a developing agent to form a developing agent image.
An image forming apparatus comprising the charging apparatus according to claim 13 as the charging means.

Images