JP3165365B2 - Toner supply mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner supply mechanism applied to a developing device of an image forming apparatus such as a copying machine, a printer, and a facsimile.

[0002]

2. Description of the Related Art An image forming apparatus has an image forming section provided with a photosensitive drum which is rotated at a constant speed, and transfers a document image formed by toner formed on the surface of the photosensitive drum to a transfer paper. Is configured to perform copying by fixing. After the surface of the photosensitive drum is uniformly charged, the photosensitive drum is exposed to a light image obtained by reading an original to form a latent image, and further, toner is adsorbed to be exposed.

[0003] The supply of toner to the surface of the photosensitive drum is
This is performed by a toner supply mechanism of the developing device. The developing device has a developing roller therein which is parallel to the photosensitive drum and is opposed to the photosensitive drum via a small gap. The toner is guided from the outer peripheral surface through the gap by the rotation of the developing roller. The toner is supplied to the outer peripheral surface of the body drum, whereby a toner image is formed on the outer peripheral surface of the photosensitive drum. And the toner supply mechanism
The toner is circulated using a screw conveyor or the like attached to the developing device as described above.

[0004]

In recent years, in order to meet the demand for downsizing of the image forming apparatus, the above-mentioned developing apparatus has been considered to be compact, and in order to realize this, a part of the toner supply mechanism is provided outside the frame. It is being considered to arrange them. However, when a part of the toner supply mechanism is disposed outside the frame, the developing device is detachably fitted in a predetermined frame, whereas the toner supply mechanism extends inside and outside the frame. Therefore, when the developing device is to be removed from the frame, a predetermined portion of the toner supply mechanism must be disassembled beforehand so that maintenance operations are extremely difficult. The problem that it becomes troublesome arises.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a toner supply mechanism capable of facilitating an operation of attaching and detaching a developing device to and from a frame, thereby facilitating a maintenance operation of an image forming apparatus. It is intended to provide.

[0006]

According to the first aspect of the present invention,
A toner supply mechanism for supplying toner to a photosensitive drum rotatably provided on a frame in an apparatus body of an image forming apparatus, wherein the toner supply mechanism is mounted on the frame so as to face the photosensitive drum, a developing device for supplying toner to the surface, and a toner hopper for reserving the toner supplied to the developing device, provided with a relay conveying unit that is provided between the toner hopper and the developing device, the relay conveying means, cylinder Swivel arm with screw conveyor inside
A pivotable arm that can supply toner from the toner hopper to the developing device;
It is possible to change the posture by turning between the retracted position retracted to a position that does not interfere with the mounting and demounting operation of the developing device with respect to the frame .
Thus, it is attached to the toner hopper .

According to the present invention, the toner is supplied to the photosensitive drum by the developing device while being transported through the transport path including the toner hopper, the relay transporting means set in the relayable position, and the developing device. Processing is performed. When the developing device is removed from the frame during a maintenance operation or the like, the interference state of the relay conveying unit with the developing device is eliminated by displacing the relay conveying unit to the retracted posture, so that it is troublesome to remove a screw. The developing device can be removed from the frame without performing any operation. Then, after the developing device is mounted on the frame in a state in which the relay conveying means is set in the retracted position, the toner is supplied to the photosensitive drum by returning the relay conveying device to the relayable position.

[0008] Then, relay transfer means medium is formed by a swivel arm screw conveyor is furnished to the tubular body, the pivoting arm, so as to pivot between the RELAY possible posture and the retracted posture DOO because attached to Nahoppa, by displacing the retracted position to pivot the pivot arm in a relay enabled position, detachable operating of the developing device relative to the frame comes to be said row. Then, by returning the turning arm to the relayable position with the developing device attached to the frame, toner can be supplied to the photosensitive drum.

In the invention according to the first aspect, the toner
As a specific configuration of the over supply structures, and trough the swivel arm,
The gutter is formed by a lid that covers the upper part of the gutter.
Is the toner from the toner hopper at the center of rotation on the base end side.
The toner introduction hole to receive the
In the part, connect the connecting cylinder downward from the lower part on the tip side of the gutter part.
By connecting the connecting cylinder to the developing device.
The toner hopper and the developing device are mutually
The connection may be made (claim 2).

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a toner supply mechanism according to the present invention, in particular, a toner supply mechanism (hereinafter referred to as a toner recycle mechanism) for circulating toner removed from a photoreceptor drum to a transfer device for developing again. 2) is an overall perspective view showing an embodiment of a copying machine to which the present invention is applied, and FIG. 2 is an internal configuration diagram thereof. The copying machine 1 includes a copying machine main body 1a and a document placing portion 1b disposed on the top of the copying machine main body 1a.
Is formed by including an optical mechanism 2, an image forming section 3 having a photosensitive drum 31, a sheet transport mechanism 4, a reversing mechanism 5, and a duplex unit 6.

The document placing portion 1b is a document holding portion for opening and closing a surface of a contact glass 1c mounted on a top opening of the copying machine main body 1a, and a document is set by manual operation. In addition, as the document placing portion 1b,
An automatic document feeder may be used, which is above the contact glass 1c and in which the stacked originals are carried one by one onto the contact glass 1c, set at the exposure position, and carried out after reading the original.

The optical mechanism 2 includes a contact glass 1c.
The original on the home position H. A first optical system 21 having a light source 211 composed of a halogen lamp and a reflecting mirror 212 that scans at the time of forward movement with reference to P, and a plurality of reflections for guiding the original image irradiated by the light source 211 and reflected on the original surface to the image forming unit 3 A second optical system 22 having mirrors 221 and 222, a lens 23 for forming the original image on the surface of the photosensitive drum 31,
A pair of guide rails 24 for guiding the first and second optical systems 21 and 22 in a reciprocating direction (indicated by arrows in FIG. 2), and the first and second optical systems 21 and 22 along the guide rails 24. Each is provided with a drive unit (not shown) that runs at a predetermined speed. The reflecting mirror 223 guides the original image passing through the lens 23 to the exposure position of the photosensitive drum 31.

The light from the light source 211 is directed toward a document set on the contact glass 1c, and is reflected on the document surface to obtain a document image. The original image is reflected by the reflecting mirrors 212, 221, and 222 as indicated by a dashed line in the figure, passes through the lens 23, and is guided to the exposure position of the photosensitive drum 31 via the reflecting mirror 223.

The image forming section 3 includes a photosensitive drum 31 rotated at a constant speed in a clockwise direction by a driving means (not shown), and a main charging section 32 around the photosensitive drum 31 from an upstream side in the rotation direction. , A developing unit 33, a toner collecting roller unit 34, a transfer unit 35, a separating unit 36, and a cleaning unit 37. The photosensitive drum 31 is a main charging unit 32
After the surface is uniformly charged, the original image is exposed to form an electrostatic latent image. This electrostatic latent image is made visible by attaching toner in the developing unit 33, and then transferred to transfer paper in the transfer unit 35. The transfer paper on which the toner image has been transferred is separated from the photosensitive drum 31 by the separation unit 36, and then guided to a fixing unit 46 described later.

The paper transport mechanism 4 is detachably provided at a lower position of the copying machine main body 1a. The paper transport mechanism 4 includes a plurality of paper feed cassettes C for storing transfer paper of a predetermined size in a stacked state. Paper feed rollers 411 and 412 for feeding the transfer paper one by one from the printer, separating roller pairs 421 and 422 for preventing double feeding of the fed paper, pairs of transport rollers 431 to 434, registration rollers for secondary paper feeding A pair 44 is provided. Further, a transport belt 45 stretched between a pair of rotating rollers 451 and 452, a fixing unit 46, a discharge roller pair 47, and a discharge tray 48 are provided downstream of the photosensitive drum 31. Transport guide section 40
Is for transporting the sheet fed from the separating roller pair 42 to the discharge roller pair 47, and is composed of plate-like bodies having a required width and arranged opposite to each other. Bypass tray 4
Reference numeral 9 designates a sheet for manually setting transfer paper of a required size. The sheet 9 includes a paper feed roller 413 and a separating roller pair 423, and merges with the transport guide section 40 on the downstream side. The fixing unit 46 includes an upper heat roller 461 and a lower pressure roller 462. The heat roller 461 is provided with a heater inside, and the pressure roller 462 is pressed against the heat roller 461 with a required pressure.

Paper cassette C or manual feed tray 4
The transfer paper fed from 9 by the paper feed rollers 411 to 413 is fed to the registration roller pair 44 via the respective conveyance roller pairs 431 to 434. The transfer paper conveyed to the registration roller pair 44 is secondarily fed in synchronization with the start timing of exposure scanning of the optical mechanism 2, and is transferred to the transfer unit 3.
5, the toner image is transferred. The transfer paper onto which the toner image has been transferred is conveyed to a fixing unit 46 via a conveyance belt 45, where the toner image is fixed on the transfer paper,
After that, the paper is discharged to a paper discharge tray 48.

The reversing mechanism 5 is a part of the conveyance guide section 40 between the fixing section 46 and the discharge roller pair 47, and rotates the transfer paper around the horizontal axis 511 by an electromagnetic solenoid (not shown). A direction switching plate 51 is provided for switching between a rotation position for guiding in the direction and a rotation position for guiding in the direction of the double-sided unit 6, which will be described later. The reverse paper guide 52, a pair of transport rollers 53 in the middle of the reverse paper guide 52, and a pair of discharge rollers 54 provided at the downstream end of the reverse paper guide 52. The transfer paper whose direction has been switched to the double-sided unit unit 6 is conveyed downward along the reversing paper guide 52, and the fixing unit is formed at a curved portion formed at a portion of the reversing paper guide 52 where the pair of conveying rollers 53 is provided. The curl formed at 46 is corrected, and the pair of discharge rollers 54 is straightened as much as possible.
It is led to.

The duplex unit 6 is for copying on both sides of a transfer sheet, and includes an intermediate tray 7 having a unit main body 60 and a re-feeding mechanism 8. The intermediate tray unit 7 includes an intermediate tray 71 on which the inverted transfer sheet is placed, and a sheet knocking unit 7 above the intermediate tray 71.
2, a nip roller 73, a paper guide 74, and a rotating plate 75 which falls on its own surface by its own weight and rotates with the transfer of the paper. The paper guide 74 is provided on the rotating plate 7.
5 is provided only on the front side of the mounting position of 5, and is pivotally supported at the upper portion and is inclined rearward with its own weight or a slight urging force downward to abut on the intermediate tray 71. The transfer paper carried out of the intermediate tray 71
On the surface of the transfer paper, and the leading edge of the transfer paper is
5 prevents stock mistakes.

The re-feeding mechanism 8 includes a re-feeding guide portion 81 formed of a plate-like body which is formed below the intermediate tray 71 and is opposed to the intermediate tray 71 at a predetermined interval. Slightly forward in the re-feeding direction, a re-feed roller 82 provided with an upper peripheral surface partially exposed, a reversing roller 83 in front of the re-feed roller 82, and a pair of rotating rollers 841 and 842
A separating belt 84 that is stretched between and rotates in a direction opposite to the re-feeding direction while being in contact with the peripheral surface of the reversing roller 83, and is disposed at an appropriate position of the re-feeding guide portion 81 at a required interval. It is formed to have a pair of re-feed rollers 851 to 853. Further, at the sheet nip position where the rotating roller 841 and the reversing roller 83 of the separating belt 84 face each other, a flexible sheet body 86 hangs downward from the unit main body 60, and the lower end thereof contacts the reversing roller 83. Installed in contact.

It should be noted that the double-sided unit 6 is provided with
The paper feed cassette C is slidable from the front side in place of the double-sided unit at this mounting position, so that a three-stage paper feed cassette can be provided. It is possible. In this case, a portion corresponding to the sheet feeding roller 411 and the separating roller pair 421 may be configured as a feeding unit, and the feeding unit may be loaded before inserting the sheet feeding cassette C.

When the transfer paper is sent from the pair of unloading rollers 54 onto the intermediate tray 71, the paper hitting portion 72 rotates and presses the rear end of the transfer paper (the front end when re-feeding) from above. The remaining curls are forcibly regulated straight, and in this state, the nip roller 73 rotates in the re-feeding direction to transfer the transfer sheet to the sheet nip position between the reversing roller 83 and the sheet body 86 to secure the nip state. And front alignment. The transfer state of the transfer paper is monitored by a rotary encoder (not shown) provided on a rotation shaft of the rotary plate 75. In this state, when there is an instruction to start re-feeding, that is, a back copy operation, the re-feed roller 82, the reversing roller 83, and the separation belt 84 start rotating, and the sheet is pressed by the hitting portion 72 from above. The paper is fed out one by one in order from the lowermost transfer paper, and is fed to the position where it joins with the transport guide unit 40 via the re-feed guide unit 81.
The guide roller 33 is guided to the photosensitive drum 31 by a pair of registration rollers 44. The transfer sheet on which the toner image has been transferred to the back surface is discharged to a discharge tray 48 via a discharge roller pair 47.

Hereinafter, the toner recycling mechanism according to the present invention will be described in detail with reference to the drawings. FIG. 3 shows the copying machine body 1
FIG. 3A is a perspective view illustrating an embodiment of a frame 3a that supports a developing device 330 in FIG. FIG. 4 is a partially cutaway perspective view showing an embodiment of the toner recycling mechanism supported by the frame 3a. The developing device 330 is mounted on a predetermined frame 3a in the copying machine main body 1a and fastened. The state is shown. FIG. 5 shows a state in which the fastening of the developing device 330 is released. FIG. 6 is a partially cutaway perspective view showing an embodiment of the developing device 330 pulled out from the frame 3a. FIG. 7 is a partially cutaway perspective view of the toner hopper, and FIG.
FIG. Hereinafter, in FIGS. 3 to 7, the XX direction is expressed as a width direction, the YY direction is expressed as a front-rear direction, and the near side of the drawing is expressed as a front or a front part, and the opposite side is expressed as a rear or a rear part. I do.

FIG. 3 shows the inside of the copying machine main body 1a (FIG. 2).
A frame 3a for supporting a developing device 330 (FIG. 4) as shown in FIG. The frame 3a includes a square base 3b formed at the bottom, a pair of side plates 3c erected from both sides in the width direction of the square base 3b, and a bottom plate 3d formed at the front of the bottom inside the square base 3b. It has a basic configuration.

An open portion 3e is formed at the rear of the bottom plate 3d in the square base 3b and is open. The photosensitive drum 31 (FIG. 4) is disposed between the side plates 3c above the open portion 3e. The transfer section 35 and the separation section 3 are provided below the section 3e.
6 (FIG. 2). Further, a cleaning unit 3 is provided between the side plates 3c at the rear end of the square base 3b.
7, a cleaning device 370 is provided.

A space for disposing the developing device 330 is set above the bottom plate 3d, and the developing device 330 introduced into this space is supported by the bottom plate 3d and provided at the front edge of the square base 3b. The developing device 330 is fastened to the frame 3a by the fastening means 3f (FIG. 4). On the outer wall surface of the left side plate 3c, there is provided a hook plate 30c extending in the front-rear direction and protruding outward from the vertical center of the side plate 3c. A toner hopper 336 (FIGS. 4, 5, and 7) forming a part of the recycling mechanism 335 is attached to 3 a.

The right side plate 3 corresponding to the opening 3e
c, a shaft hole 31a that supports a support shaft (not shown) of the photosensitive drum 31 is provided, and the collected toner T (FIG. 7) is placed on the left side plate 3c corresponding to the cleaning device 370. A toner outlet hole 37a for guiding to the toner hopper 336 is provided.

As shown in FIGS. 4 and 5, the fastening means 3f includes a pair of fastening arms 3g provided at the front edge of the square base 3b and a tip end of the fastening arms 3g. A holding plate 3h bridged so as to extend, and a later-described pivot arm 3 attached to the back surface of the center of the holding plate 3h in the width direction.
390. The fastening arm 3g is connected to the developing device 3 set in the square base 3b.
The base 30 is bent and formed so as to correspond to the outer shape of the front surface, and a base end thereof is rotatably supported by a front edge of the square base 3b so as to be rotatable around a horizontal axis (not shown).

At the base end of the fastening arm 3g, a detent piece 3 projecting toward the inside of the square base 3b as shown in FIG.
While the j is provided, a leaf spring 3k is fixed to the inside of the front edge of the square base 3b so as to press the moderation piece 3j on both sides toward the edge of the square base 3b. The moderating piece 3j is connected to the developing device 33 by the fastening means 3f.
0 in the fastening position (FIG. 4), the force of the leaf spring 3k is applied in the counterclockwise direction around the horizontal axis, and in the open position in which the fastening means 3f is opened (FIG. 5), the leaf spring 3k is attached. The three-dimensional shape is set so as to receive a clockwise force around the horizontal axis by the force, thereby stabilizing the fastening posture and the opening posture of the fastening means 3f.

The recycling mechanism 33 according to the present invention
Reference numeral 5 denotes a transport unit in the developing device 330 and the cleaning device 370 supported by the frame 3a, and a toner hopper 336. A screw conveyor is used as the transport means.

As shown in FIGS. 6 and 8, the developing device 330 includes a casing 331 and the casing 33.
A screw conveyor 337 installed in the front side of 1;
Toner supply roller (developing roller) installed on the rear side
332. The casing 33
1 has a long three-dimensional shape in the width direction, and a low terrace portion 331a is formed in front of the long three-dimensional shape.
Behind the terrace 3 bulges upward from the terrace 331a.
31b are formed. A toner introduction hole 3310 for guiding the toner T into the casing 331 is formed in a substantially central upper surface of the plateau portion 331b.

The screw conveyor 337 includes:
A first conveyor 337a disposed in the terrace portion 331a of the casing 331 so as to extend in the width direction;
Adjacent to and parallel to conveyor 337a, casing 33
The second conveyor 337 disposed in the first plateau 331b
and a third conveyor 337c adjacent to and parallel to the second conveyor 337b and disposed substantially in the center of the plateau 331b.

A partition wall 333 is erected between the first conveyor 337a and the second conveyor 337b and between the second conveyor 337b and the third conveyor 337c, and the first conveyor 337a is formed by the partition wall 333. And a second transport space 331 for transporting the toner T by the second conveyor 337b.
d is formed, and a third conveyor 337 c is provided between the rear partition wall 333 and the toner supply roller 332.
Toner supply roller 332 while conveying toner T
A toner supply space 331e for supplying the toner T is formed.

Each of the partition walls 333 has a central portion communication opening 333a at its central portion and both side portions, respectively.
And a side communication opening 333b. The first transfer space 331c is formed by the communication openings 333a and 333b.
Between the second transfer space 331d and the second transfer space 3
The toner T can flow between the toner supply space 31d and the toner supply space 331e.

Each of the conveyors 337a, 337b, 33
7c are interlocked with each other by a gear 337d provided at the left end thereof, and the direction of the spiral is different at the center. And
While the conveyors 337a, 337b, and 337c are rotated, the toner T is supplied from the toner introduction hole 3310 to the first position.
By being introduced into the transport space 331c, the toner T
Are connected to the central communication opening 333a and the side communication opening 33.
3b, they are mixed while being conveyed in the first conveyance space 331c and the second conveyance space 331d so as to draw an eight-shape, are carried into the toner supply space 331e, and rotate there. It is supplied to the surface.

The casing 331 has a toner supply window 334 on its rear surface over the entire length in the longitudinal direction, and the photosensitive drum 31 via the toner supply window 334.
Is supplied to the surface of the toner.

The cleaning device 370 has a long box-shaped casing 371 provided with a toner collecting port 371a on the front surface over the entire length in the width direction, a casing 371 provided inside the casing 371, and a leading end portion of the photosensitive drum 31. A web-shaped wiping member 372 set to be in contact with the surface, and a collection conveyor 373 composed of a screw conveyor and arranged at a lower portion inside the casing 371 so as to extend in the longitudinal direction.
It consists of:

With the cleaning device 370,
After the separation process in the separation unit 36, the photosensitive drum 31
The toner T attached to the surface of the photosensitive drum 31 is scraped off by the wiping member 372 by the rotation of the photosensitive drum 31.
The toner is collected in the casing 371 through the toner collecting port 371a.

As shown in FIGS. 4, 5, and 7, the toner hopper 336 has an agitating tank 338 having an arcuate bottom in a sectional view and a bottom surface higher than the bottom surface of the agitation tank 338. And a toner transport shelf 339 positioned on the side of the frame 3a. An introduction hole 338 c for introducing the toner T from the cleaning device 370 is provided on the rear wall surface of the stirring tank 338 on the side of the frame 3 a, and the toner T conveyed by the collection conveyor 373 is provided.
Is introduced into the stirring tank 338 through the introduction hole 338c.

The stirring tank 338 is provided with a stirring shaft 338a extending in the front-rear direction, and a stirring member 338b is integrally attached to the stirring shaft 338a. The stirring member 338b has stirring blades that protrude from the stirring shaft 338a in opposite directions and extend in the front-rear direction. A flexible member is attached to the tip of each stirring blade, and the rotation of the stirring member 338 b causes the flexible member to rub the inner wall surface of the stirring tank 338, thereby being introduced into the stirring tank 338. The used toner T is sufficiently mixed.

Above the toner transport shelf 339, there is provided a hopper inner conveyor 339a comprising a screw conveyor extending in the front-rear direction. By driving the conveyor 339a in the hopper, the toner T in the stirring tank 338 stirred by the stirring member 338b passes through a transfer passage in a turning arm (relay transfer means) 3390, which will be described later, and develops through the toner introduction hole 3310. Casing 3 of device 330
31 is introduced.

The stirring shaft 338a penetrates the front wall of the stirring tank 338 and protrudes to the outside. A joint 338d is provided at the tip of this protruding portion. A drive shaft of a drive motor (not shown) is connected to the joint 338d, and the drive shaft drives the stirring shaft 338a via the joint 338d. Also,
The center axes of the stirring shaft 338a and the hopper inner conveyor 339a penetrate the rear outer wall of the toner hopper 336 and protrude to the outside, and these shafts are interconnected by a predetermined gear 336a (FIG. 7). . Accordingly, the conveyor 339a in the hopper is also rotated by the rotation of the stirring shaft 338a driven by the drive motor (not shown).

The toner transport shelf 339 has a toner outlet hole 339b (FIG. 7) at its front end.
Is a pivot arm 339 through the toner outlet hole 339b.
It is derived toward 0. An annular joint 339c protruding downward is provided at an edge of the toner outlet hole 339b. In addition, stirring tank 3
A bearing 338e is provided at the front end of the shaft 38 so as to protrude in the horizontal direction in the direction of the frame 3a.

The revolving arm 3390 is formed by a gutter portion 3391 having a semicircular lower portion in cross section, and a lid portion 3392 which covers the upper portion and is integrated with the gutter portion 3391. In this swivel arm 3390, a toner introduction hole 3393 corresponding to the toner outlet hole 339b is formed in a cover 3392 on the base end side (left side in FIG. 7), and an edge of the toner introduction hole 3393 is formed. An annular joint 3394 externally fitted to the annular joint 339c of the toner hopper 336 protrudes upward. At the bottom of the gutter portion 3391, a vertical shaft 3395 which slidably fits in the shaft hole of the bearing 338e is hung down.

The annular joint 3394 on the turning arm 3390 side is fitted to the annular joint 3394 on the toner hopper 336 side, and the vertical shaft 3395
Is fitted into the shaft hole of the bearing 338e, so that the turning arm 3390 can turn around the vertical axis 3395.

As shown in FIG. 5, the swivel arm 3390 has a connecting cylinder 3396 communicating with the inside at the lower part on the tip side of the gutter 3391. The outer diameter of the connection cylinder 3396 is set to be slightly smaller than the inner diameter of the toner introduction hole 3310 of the casing 331 of the developing device 330, and as a result, the turning arm 3390 moves the developing device 330 as shown in FIG. The connection cylinder 3396 is fitted in the toner introduction hole 3310 in a state where the connection cylinder 3396 is located on the terrace portion 331a of the third arm 331a, so that the inside of the turning arm 3390 and the inside of the casing 331 communicate with each other.

The revolving arm 3390 has an in-arm conveyor 3397 composed of a screw conveyor disposed inside the revolving arm 3390 so as to extend in the longitudinal direction. The central axis of the in-arm conveyor 3397 protrudes outside from the distal end wall of the gutter 3391, and a first clutch 3398 is provided at the distal end.

On the other hand, the casing 331 is
1a, a pair of brackets 331f in the width direction are provided upright in a substantially right half portion.
A driving force transmission shaft 331g (FIG. 4) is rotatably supported around its own axis. A second clutch 331h opposed to the first clutch 3398 is provided at the left end of the power transmission shaft 331g, and the transfer of the revolving arm 3390 in which the second clutch 331h and the first clutch 3398 come into contact with each other. In the posture (posture in which toner can be relayed) (FIG. 4), the rotation of the power transmission shaft 331g is transmitted to the in-arm conveyor 3397.

The power transmission shaft 331g between the second clutch 331h and the left bracket 331f is fitted with a coil spring 331i for urging in the direction of extension. As shown in FIG. 4, the first clutch 3398 and the second clutch 33
1h is in contact therewith. This contact state can be released by moving the power transmission shaft 331g rightward with a finger, and by doing so, as shown in FIG.
Since the first clutch 3398 and the second clutch 331h are separated from each other, in this state, the turning arm 3390 turns the pulling arm 3390 forward and pulls it forward to open and close the developing device 330 with respect to the frame 3a (evacuation). posture)
become.

A gear 331j is provided at the right end of the power transmission shaft 331g, and the driving rotation of a drive motor (not shown) is transmitted to the power transmission shaft 331g via the gear 331j. Note that this gear 331j is
The gear 331 meshes with a gear provided on the right end of the first conveyor 337a, and also meshes with a gear provided on the toner supply roller 332 via an intermediate gear.
The rotation of j causes the first to third conveyors 337a to 337
As c rotates through the gear 337d, the toner supply roller 332 also rotates.

According to the structure of the recycling mechanism 335, as shown in FIG.
And the developing device 330 and the turning arm 3390 are fastened by the fastening means 3f.
36 and the conveyor 33 in the hopper.
9a, the in-arm conveyor 3397, the screw conveyor 337 (FIGS. 6 and 8) in the developing device 330 and the toner supply roller 332, and the recovery conveyor 373 in the cleaning device 370 are driven, so that the toner T ( FIG. 8) shows the stirring member 338b.
The toner is introduced into the swivel arm 3390 by the toner transport shelf 339 while being stirred by the conveyor 339 in the arm.
7 of the developing device 330 conveyed by the
1 is supplied.

Then, the toner T supplied into the casing 331 is transferred to each of the conveyors 337a, 337b, 337c.
The first transfer space 331c and the second transfer space 331d.
The toner is supplied to the surface of the photosensitive drum 31 from the toner supply window 334 by the rotation of the toner supply roller 332 in the toner supply space 331e.

Next, the toner T adsorbed on the surface of the photosensitive drum 31 is transferred to transfer paper by the transfer unit 35 by the rotation of the photosensitive drum 31, and the toner T remaining on the photosensitive drum 31 is rotated in the rotation direction. The charge is neutralized in the separation section 36 on the vulcanization side, so that the charge is easily separated from the photosensitive drum 31.
In the cleaning device 370, the wiping member 372 scrapes off the surface of the photosensitive drum 31 to remove the casing 3.
Collected in 71. The collected toner T is returned to the toner hopper 336 by driving the collection conveyor 373, and is thereafter circulated and conveyed.

Next, the developing device 33 for the frame 3a
The attachment / detachment operation of 0 will be described. In a state where the developing device 330 is mounted on the frame 3a (FIG. 4), to remove the developing device 330 from the frame 3a by a maintenance operation or the like, the casing 331 is pressed and fastened by the pressing plate 3h, and the turning arm is pressed by the pressing piece 3i. 339
By pulling forward the fastening means 3f that has fastened 0, the fastening arm 3g rotates clockwise around the horizontal axis of the front edge of the square base 3b against the urging force of the leaf spring 3k. This causes the fastening means 3f to assume the open position. By pulling the swing arm 3390 forward in this state, as shown in FIG. 5, the fastening means 3f also rotates clockwise around the vertical axis 3395 (FIG. 7) to assume an open posture protruding forward. . In this state, as shown by a white arrow in FIG. 5, the casing 331 of the developing device 330 is once pulled up and pulled forward, whereby the developing device 330 is detached from the frame 3a. By performing an operation reverse to this operation, the developing device 330 is mounted on the frame 3a.

According to the present invention, as described in detail above, in the toner T recycling mechanism 335 in the developing device 330, the toner hopper 33 provided outside the frame 3a is provided.
6 by rotating a swivel arm 3390, which is a transfer passage of the toner T at a connection portion with the developing device 330, around a vertical axis 3395, and thereby a transfer posture in which the swivel arm 3390 communicates with the inside of the developing device 330; Since it is rotatable between an open position that does not hinder the attaching and detaching operation of the device 330, it is difficult to remove the screwing when removing the developing device 330 mounted on the frame 3a as in the related art. Without performing the operation, the user can perform the detachment operation of the developing device 330 with respect to the frame 3a by a one-touch operation of pulling the connection cylinder 3396 forward or pushing it backward, which is extremely convenient in that the maintenance operation of the developing device 330 is easily performed. It is.

[0055]

According to the first aspect of the present invention, the relay conveying means is retracted to a position where the toner can be supplied from the toner hopper to the developing device and to a position where the relay does not interfere with the operation of attaching and detaching the developing device to and from the frame. When the developing device is detached from the frame, the relay conveyance means is displaced to the retracted posture when the developing device is detached from the frame, so that the interference state of the relay conveyance device with the developing device is eliminated. The developing device can be removed from the frame without performing a troublesome operation such as removing screws that have been used, and after the developing device is mounted on the frame in a state where the relay conveyance means is set in the retracted posture. By returning the relay conveying means to the relay-possible posture, the toner can be supplied to the photoreceptor drum. Efficacy in simplifying the maintenance operations on the developing device and a photosensitive drum that Tsu is large.

Further , since the relay conveying means is formed by a swivel arm provided with a screw conveyor, the relay conveying means can be made simple, which is advantageous in reducing the cost of the apparatus. .

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing an embodiment of a copying machine to which a toner supply mechanism according to the present invention is applied.

FIG. 2 is an internal configuration diagram of the copying machine shown in FIG.

FIG. 3 is a perspective view showing one embodiment of a frame that supports a developing device in a copying machine main body.

FIG. 4 is a partially cutaway perspective view showing one embodiment of a toner recycling mechanism supported by a frame, and shows a state in which a developing device is mounted on and fastened to the frame.

FIG. 5 is a partially cutaway perspective view showing one embodiment of a toner recycling mechanism supported by a frame, showing a state in which the fastening of the developing device to the frame is released.

FIG. 6 is a partially cutaway perspective view showing an embodiment of the developing device pulled out of the frame.

FIG. 7 is a partially cutaway perspective view showing an embodiment of the toner hopper.

FIG. 8 is a schematic cross-sectional view taken along line AA of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier 2 Optical mechanism 3 Image formation part 31 Photoreceptor drum 32 Main charging part 33 Developing part 3a Frame 3b Rising base 3f Fastening means 3g Fastening arm 3h Holding plate 330 Developing device 331 Casing 335 Recycling mechanism 336 Toner hopper 338a Stirrer 339a Inner Conveyor 337 Screw Conveyor 337a First Conveyor 337b Second Conveyor 337c Third Conveyor 370 Cleaning Device 371 Casing 372 Wiping Member 373 Collection Conveyor 3390 Swivel Arm (Relay Conveyance Means) 3391 Gutter 3392 Lid Conveyor 3397 Arm Conveyor

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satoru Yonemoto 1-2-28 Tamazo, Chuo-ku, Osaka City Inside Mita Kogyo Co., Ltd. (72) Inventor Ikuo Makie 1-2-28 Tamazo, Chuo-ku, Osaka Mita Inside Industrial Co., Ltd. (72) Takashi Nagashima 1-2-2, Tamazo, Chuo-ku, Osaka-shi Mita Industrial Co., Ltd. (56) References JP-A-6-110329 (JP, A) JP-A-4-298773 ( JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 13/08-13/095 G03G 15/08-15/095

Claims (2)

(57) [Claims] 1. A toner supplying mechanism for supplying the toner to the photosensitive drum which is rotatably provided on the frame of the apparatus main body of an image forming apparatus, is mounted so as to be opposed to the photosensitive drum to the frame A developing device for supplying toner to the outer peripheral surface of the photosensitive drum, a toner hopper for storing the toner to be supplied to the developing device, and a relay conveying means interposed between the toner hopper and the developing device; The conveying means has a screw conveyor inside the cylindrical body.
Formed by a swiveling arm,
The toner hopper is attached to the toner hopper so that the attitude can be changed by turning between a relayable position at which toner from the toner hopper can be supplied to the developing device and a retracted position retracted to a position that does not interfere with the attaching / detaching operation of the developing device with respect to the frame. A toner supply mechanism. 2. The swing arm according to claim 1, further comprising: a gutter portion;
And a lid covering the upper part.
The toner from the toner hopper is applied to the rotation center position on the end side.
Having a toner introduction hole perforated to receive
The gutter section is protruded downward from the lower part on the tip side of the gutter section.
Connecting cylinder connected to the developing device.
The rotation of the toner hopper and the developing device
The toner supply mechanism according to claim 1, wherein the toner supply mechanism is configured to be connected to each other through a system .