JP2556905Y2 - Electrophotographic equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus used as a facsimile, a printer, or a copying machine, and more particularly, to a cleaning mechanism provided with a cleaning mechanism capable of transporting residual toner removed from a photosensitive drum to a drum shaft end. The present invention relates to an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, an electrophotographic apparatus applied as a facsimile, a printer, or a copying machine is known. This type of apparatus generally visualizes a toner image carried on a photosensitive drum by a developing device. Thereafter, the toner image is transferred to a recording sheet guided to a transfer position in synchronization with a registration roller, and the recording sheet is discharged along a discharge path after image fixing while being transported along a transport path. After the toner image is transferred, the residual toner adhering to the photoconductor drum is removed by using a cleaning mechanism, and then the drum surface is uniformly charged by using an eraser and a charger, so that the above operation can be repeated. . This type of cleaning mechanism generally includes a cleaning blade that scrapes off toner adhered to the surface of the photoconductor drum, and a screw-shaped transport member that guides the scraped toner to a collection bottle disposed on the drum shaft end side. I have.

[0003]

It is necessary to replace the collection bottle appropriately for every number of printed sheets. Therefore, the printing is continued without knowing that the toner is full and the inside of the machine is caused by overflow. Not only is there a danger, the user is also forced to replace the collection bottle regularly,
Maintenance work becomes complicated.

Although it is conceivable to increase the volume of the recovery bottle in order to solve such a drawback, it is a design problem to arrange a large-capacity toner recovery container at a limited location such as the shaft end of the cleaning mechanism. Is increased, and this is contrary to the demand for downsizing the device.

A second conveying member is provided so as to extend between the shaft end (end) of the conveying member (hereinafter referred to as a screw shaft) and the developing container, and the conveying member allows the residual toner to be stored in the developing container. The proposed device has been proposed. (Japanese Patent Publication No. 57-18187)

In the above-mentioned prior art, in order to make it possible to reuse the residual toner contained in the developing container, the residual toner is mixed with a sufficiently large amount of developer to destroy bridge caking and the like of the residual toner. Although the powder is returned to a stable powder state, such a configuration that the developer can be reused always requires a sufficient amount of the developer in the developing container, and also in order to break the caking. A mixing means is required, rather than complicating the structure and restricting the design. In addition, paper powder and the like are mixed in the residual toner, so that the developer returns to a highly pure and highly stable developer. It is difficult to make it.

The provision of the second transport member as described above requires an independent drive source for driving the transport member,
The configuration of the apparatus becomes complicated and the size of the apparatus is restricted.

In order to solve such a drawback, it is conceivable to connect the transport member to a drive system on the apparatus main body side. However, in such a configuration, synchronization with the screw shaft side is not necessarily achieved, and the stellate shaft end side is not provided. , The residual toner may overflow.

In view of the drawbacks of the prior art, the present invention provides a toner collecting section (container, space) in the apparatus, but does not complicate the apparatus configuration and does not hinder the miniaturization of the apparatus. An object of the present invention is to provide an electrophotographic apparatus capable of forming a collection unit and exchanging the collection unit at an accurate interval without causing overflow.

[0010]

SUMMARY OF THE INVENTION The present invention has a spiral blade extending in a direction parallel to the drum axis for conveying the residual toner removed from the photosensitive drum to the end of the drum axis. A first conveying unit including a screw shaft, a residual toner collecting unit disposed on a drum shaft end side of a toner container detachably attached to a developing device that forms a toner image on the photosensitive drum side, and a drum shaft In a plane orthogonal to the drum shaft on the end side, the terminal end of the screw shaft constituting the first transporting means is arranged downward, and the toner receiving port of the residual toner collecting section is arranged upward, and the space between the two is arranged. A second transporting means which is disposed obliquely upwardly as if being bridged,
The second conveying means is composed of a rubber-like belt in which partition walls made of a flexible elastic material are erected at predetermined intervals on an outer peripheral surface, a pulley for rotating the belt, and a frame body for covering these. The partition wall is configured to be curved rearward on the inner wall surface of the frame on the upstream side in the belt rotation direction of the residual toner discharge port on the belt mechanism side provided at a position facing the residual toner receiving port while being configured with a belt mechanism. A biasing means for biasing the elastic force is provided.

[0011]

According to the present invention, since the amount of developer used in the toner container and the amount of residual toner discharged are highly correlated, the volume of the toner collecting section is reduced by the amount of developer in the toner container. If the setting is made in accordance with the above, the toner container replacement time and the collection unit replacement time match, and the toner container replacement time can be automatically determined by the developer detection sensor and the number of printed sheets. The collection section can be exchanged with the container with high accuracy.

In addition, the fact that the second conveying means is located at the end of the drum shaft, together with the collecting portion, allows the toner container to be disposed not at the center or rear side of the toner container but in an area outside the image forming area on the end of the drum shaft. Even when a cleaning mechanism and a developing device are disposed on both sides of a photosensitive drum, for example, the second conveying means may be used to connect the two in a straight line without detouring around the drum. As a result, the configuration can be simplified.

Further, in the present invention, via a second conveying means extending along a surface direction orthogonal to the drum axis,
In order to communicate between the end of the conveying means and the toner collection unit,
The collection position of the collection unit is not limited to the end of the first transport means, in other words, the vicinity of the cleaning mechanism, and can be arranged at the most preferable position in the apparatus. In this case, since the toner container has a rotating shaft for stirring, it is not driven only from the screw shaft of the first conveying means as shown in the embodiment described later, but by using the rotating shaft on the toner container side. Second
It is also possible to drive the transfer means, and the design freedom is high in this aspect as well.

In this case, in the present invention, in particular, the second
The conveying means is a belt mechanism comprising a rubber-like belt in which partition walls made of a flexible elastic material are provided upright at predetermined intervals on an outer peripheral surface, a pulley for rotating the belt, and a frame body surrounding these. With this configuration, the pulley can be directly fitted to the end of the rotary shaft, and the width and thickness can be set smaller than the number of parts, so that space can be saved, which is preferable.

Further, the belt is constituted by a rubber belt in which partition walls made of a flexible elastic material are erected at predetermined intervals on the outer peripheral surface, so that the residual toner dropped onto the belt from the screw shaft is formed. Can be reliably held and transported in the space sandwiched between the upper and lower partition walls without slipping down. As a result, even when the belt mechanism is disposed obliquely upward, residual toner does not accumulate at the lower part of the belt. Reliable transport is possible.

Particularly, in the present invention, the partition wall is curved rearward on the inner wall surface of the frame on the upstream side in the belt rotation direction of the residual toner discharge port on the side of the belt mechanism provided at a position facing the residual toner receiving port. By providing the urging means for urging the elastic force, the toner adhering to the partition walls and the toner stored in the space between the partition walls by the urging force are forcibly discharged to the toner collecting unit side. In addition, the cleaning is performed every time the belt rotates, and the contamination of the residual toner on the belt does not occur.

Further, since the residual toner is not simply dropped by gravity but is introduced into the toner receiving port of the collecting section with an urging force in accordance with gravity, the residual toner is scattered in a wide range in the collecting section and spread to a uniform wide range. Therefore, even if the collecting section is enlarged as in the related art, there is no possibility that a toner hill is formed in a part and the residual toner overflows from the toner receiving port.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; However, unless otherwise specified, dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Not just.

FIG. 1 shows the internal configuration of an electrophotographic apparatus according to an embodiment of the present invention. In detail, the apparatus has a substantially rectangular shape with the right side in the drawing as an operation surface side, and a photosensitive drum 1 is disposed at a substantially central portion thereof.
The exposure optical system 2, the developing unit 3 at the right side, the transfer unit 4 below, and the cleaning mechanism 5, the eraser 6, and the charging unit 61 at the left side are arranged at the upper position along the rotation direction. A known electrophotographic process is performed while rotating the body drum 1 in the direction of the arrow.

Below the photosensitive drum 1, a transfer unit 10 in which the transfer unit 4 and the paper feed cassette 13 are integrated is disposed over almost the entire area of the apparatus. Opening 2 provided on the operation surface side on the right side in the figure
1 and can be integrally pulled out together with the paper feed cassette 13.

That is, the transport unit 10 includes a paper feed cassette housing 11 formed substantially over the entire bottom area of the apparatus.
A unit body 12 having a conveyance path formed on the upper surface of the storage section 11 along a direction substantially tangential to the transfer position of the drum 1
The main body is composed of a paper feed roller 8, a registration roller 9,
The transfer unit 4 and the conveyance guide 14 extending to the entrance end of the fixing unit 30 are arranged / formed.

In the storage section 11, a paper feed cassette 13 is provided.
Is detachably mounted, and the transfer unit 10 is mounted on the apparatus main body side or the transfer unit 1
After the attachment / detachment 0 is detached, the sheet feeding cassette 13 can be taken out.

On the other hand, the fixing unit 30 comprises a fixing roller pair 31
And a discharge roller pair 32 disposed on the exit side thereof. The switching operation of the switching lever 23 disposed on the downstream side of the fixing unit 30 causes the recording material after image fixing to pass through the reversing guide 24 and the discharge roller 27. The paper discharge to the upper surface of the apparatus and the paper discharge to a paper discharge tray 25 provided on the left side wall of the apparatus can be selectively performed.

The main body of the apparatus includes a housing portion 26 on the upper wall of the apparatus extending from the left side wall including the reversing guide 24 to the upper surface of the developing device 3 through the paper discharge section on the upper surface of the apparatus. The toner container detachably attached to the upper portion of the developing device 3 is configured to be easily replaceable.

Next, a description will be given of the cleaning mechanism 50, the toner container 70, and the mechanism for collecting the residual toner, which are main components of the present invention. First, the cleaning mechanism 5
As shown in FIG. 1, a cleaning blade 51 for scraping off residual toner attached to the drum peripheral surface and a screw shaft 5 for conveying the scraped toner to the drum shaft end side.
Consists of two. As shown in FIG. 1, the screw shaft 52 is formed so as to surround a spiral blade 54 in a spiral shape around a drive shaft 53 extending in parallel with the drum 1, and a downstream side of the screw shaft 52 in the helical rotation direction, A drive shaft end 52a extending further from the opening 18 of the drum frame 19 for supporting the drum 1 toward the outer wall of the apparatus, and having a rectangular cross section at the extended end.
To protrude.

Reference numeral 60 denotes the open end 1 of the drum frame 19.
9a and a second fitting portion 63a fitted and held in the concave portion 19b of the frame 19 via the pulley bearing 64.
The transport mechanism 60 includes a drive pulley 61 fitted to the screw shaft end 52a, a driven pulley 65 disposed at a position facing an opening 72 of a toner collecting section 71 described later, and both pulleys. A belt 62 stretched between the belts 61 and 65 and a frame 63 surrounding these belts, and along the inner side wall space of the apparatus located outside the recording paper transport path, in other words, on the axial end side of the photosensitive drum 1 The narrow space is connected to the drum shaft 1a.
And extends obliquely upward toward the toner container 70 along a plane perpendicular to the plane.

The drive pulley 61 has a shaft hole 61a formed in the shaft end on the other end while supporting one end on the side wall surface of the frame 63, and is configured to be fittable with the screw shaft end 52a.
The belt 62 is formed of a rubber belt having a partition wall 66 made of a flexible elastic material provided on the outer peripheral surface at predetermined intervals. As shown in FIG. 2, the frame 63 has a substantially oval shape surrounding the belt 62, and has an opening 63 c on the drive pulley 61 side that can be fitted to the drum frame opening end 19 a, and a portion below the driven pulley 65. The side facing the opening 72 of the toner collecting section 71 is opened to form a toner outlet 63d.

The ceiling wall above the driven pulley 65 of the frame 63 is formed in a knife edge shape so as to gradually become narrower along the moving direction of the belt 62, and the partition wall 66 is gradually directed rearward. The partition wall 66 is configured to be capable of reversing while elastically releasing the pressure contact at the stepped portion 67a at the end of the edge 67 while being bent.

As shown in FIG. 4, the toner collecting portion 71 is integrally formed by using an engaging hole 78 of an engaging plate 79 provided on the side end of the toner container 70 and an engaging projection 77 provided on the toner collecting portion 71 side. The side facing the belt 62 mechanism is formed obliquely along the belt 62 while extending along the side of the developing unit 3 to the lower end thereof in order to increase the residual toner storage volume. An opening 72 is formed on the side of the belt mechanism 60 facing the toner discharge port 63d. In the drawing, reference numeral 68 denotes an agitating member for agitating the accumulated toner in the collection container, and exposes a rotating shaft end 69a to a wall surface 71a facing the toner container 70. On the other hand, the toner container 70
The other end of a toner agitating shaft (not shown) connected to a toner supply driving source (not shown) is provided on the wall surface side of the Key hole 7
The rotation shaft end 69a is configured to be fitted to 5a. Therefore, the collecting section 71 can be taken out together with the toner container 70 upward.

Next, the operation of the present invention will be described. First, the residual toner on the peripheral surface of the photosensitive drum 1 is scraped off by the cleaning blade 51, and then the screw shaft 52 is rotated to use the spiral blade 54 to convey the residual toner to the axial end of the drum 1. At this time, the spiral blade 54
Since the toner enters the frame 63 of the belt mechanism 60, the toner can be smoothly carried into the mechanism 60.

Since the driving pulley 61 of the belt mechanism is connected to the screw shaft 52, the belt mechanism 60 rotates in synchronization with the screw shaft 52, and the partition wall 66 of the belt 62 is used. Then, the residual toner is directly conveyed to the driven pulley 65 side.

While the partition wall 66 is gradually curved backward by the knife edge 67 on the driven pulley 65 side, the pressing is released at the end of the edge 67 and the partition wall 66 is urged forward by a repulsive force. It will go around the driven pulley 65. As a result, the toner between the partition walls 66 is forcibly discharged to the toner collecting section 71 together with the toner adhered to the partition walls 66 by the urging force.

After the above state is repeated for each printing and set-up operation, when the empty indication of the developer in the toner container 70 is made by a sensor (not shown), the housing on the upper wall of the apparatus reaching the upper surface of the developing apparatus 3 The unit 26 is divided and opened, and the toner container 70 is replaced together with the collecting unit 71.

[0034]

As described above, according to the present invention, even if a toner collecting section (container, space) is provided in the apparatus, the apparatus configuration is not complicated and the apparatus is not obstructed in downsizing. The toner collecting section can be formed, and the collecting section can be replaced at an accurate interval without causing overflow. Further, according to the present invention, as described above, the second transport means including the belt mechanism is provided between the screw shaft and the toner collecting section, but the drive source of the second transport means is not required, and the second transport means is not required. Also, the toner can be collected smoothly without any risk of overflow or accumulation of residual toner.
And so on.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram showing a configuration of an axial end side of a cleaning mechanism of the electrophotographic apparatus shown in FIG. 3;

FIG. 2 is a schematic diagram showing a configuration of a toner collecting unit of the image forming apparatus shown in FIG.

FIG. 3 is an overall configuration diagram of the electrophotographic apparatus according to the embodiment of the present invention.

FIG. 4 is a schematic perspective view of the toner container shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor drum 5 cleaning mechanism 3 developing device 70 toner container 71 residual toner collecting unit 50 transport unit (51 connection unit) 60 second transport unit 61, 65 pulley 62 belt

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-81067 (JP, A) JP-A-61-186979 (JP, A)

Claims (1)

(57) [Scope of request for utility model registration] 1. A method for removing residual toner removed from a photosensitive drum.
Direction parallel to the drum shaft to transport to the drum shaft end
From the screw shaft, which has a spiral blade on the shaft
And a developing device for forming a toner image on the photosensitive drum side.
Is located on the drum shaft end side of the toner container
The remaining toner collecting section, and the above-mentioned plane in a plane orthogonal to the drum shaft at the end of the drum shaft.
Lower the end of the screw shaft that constitutes the first conveying means
The toner receiving port of the residual toner collecting section is
And tilt them diagonally upwards as if they span between them.
And a second transporting means disposed on the outer peripheral surface at predetermined intervals.
Rubber belt having a partition wall made of conductive material erected and the bell
Consists of pulleys that rotate
A belt mechanism, and the belt provided at a position facing the residual toner receiving port.
Upstream of the residual toner discharge port on the belt mechanism
The partition wall is curved rearward on the inner wall of the frame
An electrophotographic apparatus provided with an urging means for urging a force.