JP3097438B2 - Roller device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, in a facsimile or the like as an image forming apparatus, a toner image formed on the surface of a photosensitive drum 101 is transferred by a transfer electrode 102 as shown in FIG. The fixing device 1 transfers the transferred copy sheet 103 without using a sheet conveyance belt.
There is one configured so that it can be directly transported to the printer 04. Here, FIG. 6 is a configuration diagram illustrating an example of an image forming process of a conventional image forming apparatus.

According to this configuration, instead of omitting the paper transport belt, it is necessary to newly provide a pre-transfer roller 105 upstream of the transfer electrode 102 with respect to the paper transport direction. Not only reduces the body size but also reduces product costs.

A pre-transfer roller 105 drives a driving device to apply a conveying force for conveying the toner image to the copy sheet 103 separated from the surface of the photosensitive drum 101 by the separation electrode 106 to the fixing device 104. (Not shown) so as to be rotatable.

[0005]

However, in the above configuration, the assemblability is not always simple in order to ensure that the rotational force from the driving device can be transmitted to the pre-transfer roller 105. There was also a problem in maintenance such that it could not be easily removed during inspection.

[0006]

According to the present invention, there is provided a plate-shaped frame having a notch formed therein, a groove rotatably supporting a roller, and being fitted into and removed from an edge of the notch. And bent in a substantially “heavy” shape
When the groove is fitted to the edge of the notch, the supporting member has a support member having at least a lower portion of the supporting member, and the supporting member always lifts the supporting member elastically. And a resilient member.

[0007]

According to a first aspect of the present invention, a plate-like frame having a notch formed therein and a roller are rotatably supported, and are fitted to an edge of the notch so as to be freely inserted and removed. A support member having a groove portion provided on the plate-shaped frame, wherein the groove portion is fitted to an edge of the cutout portion, the support member abuts at least a lower portion of the support member, and always lifts the support member elastically. And a provided elastic body.

According to a second aspect of the present invention, the roller is a roller that conveys the sheet to the fixing device side, and is provided upstream of a transfer device that transfers an image to the sheet based on the conveying direction of the sheet. The elastic body is a roller device that is a spring member.

[0009]

According to the first aspect of the present invention, the notch is formed in the plate-like frame, the support member rotatably supports the roller, and the groove is freely fitted into and removed from the edge of the notch. The elastic body is provided on the plate-shaped frame, and when the groove is fitted to the edge of the notch, the elastic body comes into contact with at least a lower portion of the support member, and the support member always has elasticity. lift. This allows
The support member is reliably supported with a predetermined elasticity, and the roller can be removed by pulling out the groove from the edge of the notch.

According to a second aspect of the present invention, the notch portion is formed in the plate-shaped frame, and the support member is provided on an upstream side of a transfer device for transferring an image to the sheet based on a sheet conveying direction. A roller that rotatably supports a roller that conveys the sheet to the fixing device side, has a groove that is freely fitted into and removed from an edge of the notch, and a spring member is provided on the plate-shaped frame; When the groove is fitted to the edge of the notch, the groove abuts at least the lower portion of the support member, and always lifts the support member elastically. Thus, the support member is reliably supported with a predetermined elasticity, and the roller can be removed by pulling out the groove from the edge of the cutout.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external perspective view of a copying machine having a roller device according to an embodiment of the present invention, in which a front panel of the copying machine has been removed, and an upper portion of the copying machine has been lifted so that the internal structure can be seen. FIGS. 2 and 3A and 3B are perspective views showing the configuration of the roller portion of the roller device of the present embodiment. The configuration of the present embodiment will be described with reference to FIG. I do.

As shown in FIG. 1, the upper part of the copying machine main body 1 is separated from the lower part for the purpose of making it easy to check the internal condition at the time of inspection or the like and to facilitate the work. Then, with the right side of the main body as a fulcrum, it is lifted diagonally upward from the left side and can be held as it is.

In FIG. 1, there is a paper feed port (not shown) on the right side of the copying machine main body 1, and the photosensitive drum 2 is moved when the upper part of the copying machine main body 1 is securely fitted to the lower part. 1
The driving spur gear 4 of the driving device 3 provided on the lower rear side
And a drum-side spur gear 5 to be meshed with the back side flange portion 2a at one end thereof. Further, the photosensitive drum 2 has a transmission spur gear 6 for transmitting a rotational force to a pre-copying roller 7 as a roller of the present invention on a front side flange portion 2b at the other end of the photosensitive drum 2, and the above-described copying machine It is rotatably held at a predetermined position on the upper part of the main body 1. The pre-transfer roller 7 moves the paper (not shown) based on the conveyance direction.
On the upstream side of the transfer electrode 17, a pair of notches 31, which will be described later, are provided on the front plate frame 9 and the rear plate frame 10 fixed to the lower upper surface of the copying machine main body 1, respectively.
(See FIG. 4 (a)).
A separation electrode (not shown) for separating the paper from the surface of the photosensitive drum 2 is provided on the downstream side of the transfer electrode 17 for transferring the original image onto the paper, and the transferred toner image is provided on the downstream side thereof. A fixing device 14 for fixing the sheet to the sheet is provided, and a sheet discharge port 15 is further provided downstream thereof. The pre-copy roller 7 mainly conveys the paper to the fixing device 14, but also applies a separating force for separating the paper on which the transfer has been completed before from the surface of the photosensitive drum 2. Can be done.

As shown in FIG. 2, a pair of bearings 11 and 12 as supporting members of the present invention have the same shape provided on both sides of the pre-transfer roller 7 to rotatably support the roller shaft 7a. A roller spur gear 1 before transfer
Reference numeral 3 denotes a roller shaft 7a on the further front side (right side in the drawing) of the bearing portion 11 provided on the front side, with reference to the case viewed from the front side of the copying machine main body 1 (hereinafter referred to as the same reference).
The upper portion of the copying machine main body 1 is to be engaged with the transmission spur gear 6 of the photosensitive drum 2 when the upper portion of the copying machine main body 1 is securely fitted to the lower portion as described above, and the roller portion 7b Is a rubber roller that is provided between the pair of bearing portions 11 and 12 and that is formed so as to cover the entire circumference of the roller shaft 7a and that conveys paper. Further, the bearing portion 12 located on the back side is held at the back end portion of the roller shaft 7a in a positional relationship as if the bearing portion 11 provided on the front side was moved in parallel. . The purpose of using two identical parts as the pair of bearing parts 11 and 12 is to use common parts and dies to reduce total cost and prevent assembly errors of parts. It is to improve the assemblability and reliability. Further, the pair of bearing portions 11 and 12 are held in such a manner as to have a positional relationship as if the above-mentioned one component was moved in parallel with respect to the roller shaft 7a.
By using two identical parts as a pair of bearings having a substantially “H” shape for the reason described below,
This is because a predetermined function can be exhibited. Here, FIG. 2 shows the pre-transfer roller 7 of this embodiment.
It is a perspective view of.

Further, since the detailed portions of the pair of bearing portions 11 and 12 are the same parts, based on the bearing portions 11 provided on the front side, the parts shown in FIGS.
This will be described with reference to FIG. Here, FIG.
FIG. 4 is an enlarged perspective view of a pre-transfer roller shown in FIG. FIG. 3B is a perspective cross-sectional view showing a cross section of the bearing portion shown in FIG.

As shown in FIG. 3A, the bearing 11
Has a substantially cylindrical support portion 11a for rotatably supporting the roller shaft 7a, and a bearing protrusion 11b protruding from a part of the support portion 11a in a direction perpendicular to the axial direction of the roller shaft 7a is substantially " It is formed in the shape of a letter "", and the short side of the letter "" is connected to the support portion 11a side. Here, the reason why the bearing projection 11b has a substantially “H” shape is to take into account the mechanical action, the component arrangement, and the like. The front end of the bearing projection 11b has a front end 21 that is closer to the roller shaft 7a than the front end 21.
, And a step portion 23 is provided between them.
Numeral 2 is continuous with the left and right side surfaces formed between both the front surface and the rear surface of the bearing projection 11b with a smooth curved shape.

As described above, the bearing projections 11 having different lengths from the roller shaft 7a at the distal end between the near side and the far side.
Regarding b, a bent portion 11c having a substantially “H” shape from the front end portion 21 is formed on the left and right side surfaces on the side where the step portion 23 of the below-described front side projection portion 21a having the front end portion 21 exists. The notch grooves 24 and 25 (see FIG. 3 (b)) having a predetermined width A (see FIG. 3 (b)) and a predetermined depth are provided straight in a region slightly beyond the point. As shown in FIG. 3 (b), the cross-sectional shape has a cutout shape of an “L” near the stepped portion 23, and a bent portion 1 near the stepped portion 23.
Up to a point slightly beyond 1c, the groove shape is a U-shape. Further, the notch grooves 24 and 25 are formed in the bearing protrusion 11.
b are formed on the same plane perpendicular to the axial direction of the roller shaft 7a on both left and right side surfaces of the cutout groove 2.
The bottom surfaces 4 and 25 are parallel and maintain a constant distance B. Here, the notch grooves 24 and 25 are assumed to be temporary boundaries, and the near side of the bearing protrusion 11b including the notch grooves 24 and 25 is referred to as the near side protrusion 21a.
The bearing projection 11b, which is adjacent to this and has the distal end portion 22 on the back side, and which is further on the back side than the boundary portion, is referred to as the back side projection portion 22a. Further, the thickness of the rear projection 22a (based on the axial direction of the roller shaft 7a in the thickness direction) is formed so as to be larger at least at the front end portion than the thickness of the front projection 21a.

On the other hand, the front and back plate frames 9, 1
0 (FIG. 4A) (FIG. 4A shows the front plate frame 9 and the rear plate frame 10
As shown in the figure, when the copier main body 1 is viewed from the front, a cutout portion 31 of the same shape that is inclined at a predetermined angle from the upper left to the lower right of the copier main body 1.
Are formed one by one. The notch width W is slightly larger than the distance B between the bottom surfaces of the notch grooves 24 and 25 (W> B), and the edge 31 of each notch 31 is provided.
a and the thickness t in the vicinity thereof are the above-described notch grooves 24,
25 is slightly smaller than the width A (t <A), and the notch depth D of the notch 31 is equal to the notch groove 2.
It is configured to be longer than the length of 4,25.
The inclination direction of the notch 31 substantially coincides with the inclination direction of the upper portion of the copying machine main body 1 when the upper portion of the copier main body 1 is separated from the lower portion and lifted obliquely upward from the left side with the right side of the main body as a fulcrum. ing. Here, FIG. 4A is a side view of the plate-side frame 9 on the near side as viewed from the near side, and shows a state where the pre-transfer roller 7 is not attached.

A coil spring 32 as an elastic body of the present invention is attached to each of the plate frames 9 and 10 at a predetermined position. As shown in FIG.
As shown in (a), so as to cross the notch 31,
The notch grooves 2 attached to the inner surface of each of the upper frames 9 and 10 and provided in the bearing projection 11b.
4 and 25 are fitted to the edge 31a of the notch 31 (see FIG. 4D), and the distal end 22 on the far side contacts the coil spring 32 (see FIG. 4B). Further, it is configured such that the bearing projection 11b can be pushed in with a force that overcomes the restoring force of the coil spring 32 (see FIG. 4C). Here, FIG. 4B is a side view of the front plate frame 9 as viewed from the front side. The pre-transfer roller 7 is attached, and the rear end portion 22 is in contact with the coil spring 32. FIG. 4C shows the state.
FIG. 5 is a side view of the plate-side frame 9 on the front side as viewed from the front side, showing a state in which the bearing projection 11b is pushed in with a force that overcomes the restoring force of the coil spring 32 from the state shown in FIG. I have. Further, FIG.
(B) it is a Y ₁ -Y ₂ cross-sectional view along a line such as a bearing protrusion 11b shown in.

In the above configuration, FIGS.
The operation of this embodiment will be described with reference to (a) to (d).

When performing maintenance or the like of the pre-transfer roller 7 or the like, the worker releases the lock (not shown) between the upper and lower portions of the copying machine main body 1 and lifts the diagonally upward from the left side with the right side of the main body as a fulcrum. Then, the upper part of the copying machine body 1 is opened.

When the upper part of the copying machine body 1 is opened, the photosensitive drum 2 held at a predetermined position on the upper part moves upward and meshes with the driving spur gear 4 and the pre-transfer roller side spur gear 13. The state is released. Until then, the pre-transfer roller 7, which has been pressed by the predetermined force from the photosensitive drum 2 via the pre-transfer roller side spur gear 13, etc.,
The notch grooves 24 and 25 provided in the cutouts 1 and 12 are fitted to the edge 31 a of the notch 31, and the tip 21 abuts against the coil spring 32, and the coil spring 32
Thus, a state of being held elastically at a predetermined position is maintained by a balance with a restoring force acting in a direction of lifting with a predetermined elastic force. However, since the predetermined force applied to the pre-transfer roller 7 from the photosensitive drum 2 is removed, the leading end 21 is lifted by the predetermined elastic force of the coil spring 32, and the pre-transfer roller 7 is It moves slightly obliquely upward while maintaining the state of being held.

In order to remove the pre-transfer roller 7 held in the notch portion 31 in this manner, the upper left part of the copying machine main body 1 is separated from the lower part, and the left upper part is largely open. By lifting the pre-transfer roller 7 in the direction of, the roller is completely pulled out from the notch 31 and can be easily removed.

When the necessary maintenance is completed for the removed pre-transfer roller 7, the operator attaches the pre-transfer roller 7 to the above-mentioned predetermined place again.

That is, the notch grooves 24, 25 provided in the pair of bearing portions 11, 12 of the pre-transfer roller 7 are fitted to the corresponding edge portions 31a of the pair of notch portions 31, respectively. At this time, the distal end portion 22 on the far side abuts on the coil spring 32 (see FIG. 4B) and is held at one end.

Then, the upper part of the copying machine main body 1 in the opened state is moved downward and fitted to the lower part, whereby the copying machine 1 is automatically locked.

When the upper part of the copying machine body 1 is moved downward, the photosensitive drum 2 moves downward, so that the pre-transfer roller side spur gear meshed with the transmission spur gear 6 provided on the photosensitive drum 2. 13 and the like, and the coil spring 3
The pair of bearings 11, with a force that overcomes the restoring force of 2,
12 slides obliquely downward, and is elastically held at a predetermined position. At this time, the thickness of the rear projection 22a, whose tip abuts against the coil spring 32, is thicker than the thickness of the front projection 21a in consideration of the relationship with the diameter of the coil spring 32 and the like. To coil spring 32
Will not come off. Further, when receiving a force applied from the photosensitive drum 2 or the like, as described above, each of the bearing portions 11, 1
In order to allow the slide 2 to smoothly slide the edge 31a of the notch 31, the front protrusion 21a having the notch grooves 24 and 25 is longer than the rear protrusion 22a. With such a structure, the notch grooves 24,
25 can be made as long as possible, and the notch 31
Since the number of contact portions with the edge portion 31a increases, the movement of each of the bearing portions 11 and 12 becomes more stable.

As described above, the pair of bearing portions 11 and 12
Is held elastically at a predetermined position by the restoring force of the coil spring 32 in a substantially vertical direction, and the notch grooves 24 and 25 are formed in the corresponding plate-shaped frames 9 and 10. Since the pair of cutouts 31 are fitted to the edges 31a of the pair of cutouts 31, they are securely held without shifting in the horizontal direction, and the attachment and detachment of the pre-transfer roller 7 can be easily performed. Further, from this, it is clear that the assembly in the manufacturing process of the pre-transfer roller 7 becomes easy.

In the above embodiment, a case where a coil spring is used as the elastic body of the present invention has been described. However, the present invention is not limited to this. For example, a leaf spring, rubber, or a cushion material having elasticity may be used. Does not matter.

In the above embodiment, the notches 24, 2
5 is closer to the coil spring 32.
Although the case where it is formed to be longer than the rear side protruding portion 22a that abuts on the elastic body has been described, the present invention is not limited to this. The contact may be configured to be longer.

Further, in the above-described embodiment, the case where the thickness of the rear projection 22a whose leading end abuts on the coil spring 32 is made thicker than the thickness of the front projection 21a has been described. Instead, for example, both may have the same thickness, or the contact surface that contacts the elastic body is inclined as shown in FIG. A certain coil spring 32 may have a structure that is difficult to come off. In short, the elastic body abuts.
The shape of the lower part of the support member does not matter. Here, FIG. 5 is an explanatory view showing another example of the shape of the lower portion of the support member, and FIG. 4B shows the front-side bearing projections, the coil springs, and the like of the front-side plate-shaped frame 9 in FIG. It is an arrow view when it sees according to Q.

In the above-described embodiment, the case where two identical parts are used as the pair of bearing portions 11 and 12 as the supporting members has been described. However, the present invention is not limited to this. As a matter of course, different parts may be used.

Further, in the above embodiment, the case where the coil spring 32 as the elastic body is attached to the back side of each plate-like frame has been described. However, the present invention is not limited to this.
Both may be attached to the front side of the board frame, or one of them may be attached to the front side of the board frame,
The other side may be the back side. In short, as long as the elastic body is attached to the plate-like frame, the attaching position of the elastic body does not matter.

Further, in the above-described embodiment, the case where the pre-transfer roller 7 as a roller has a configuration in which the rotational force is directly transmitted from the photosensitive drum 2 has been described. However, for example, the rotational force transmission path is indirect. Alternatively, the rotational force may be transmitted from another drive device, and the transmission path of the rotational force or the type of the drive device that generates the rotational force is not limited.

The present invention is applicable not only to a copying machine but also to other image forming apparatuses having a roller device such as a printer and a facsimile.

[0037]

As is evident from the above description, the present invention has the advantage that it is easier to assemble and can be easily removed and attached as compared with the prior art.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a copier having a roller device according to an embodiment of the present invention, in which a front panel is removed and an upper portion of the main body is lifted so that an internal structure can be seen.

FIG. 2 is a perspective view of a pre-transfer roller of the present embodiment.

3 (a); FIG. 3 (b) is an enlarged perspective view mainly showing a bearing portion on the near side of the pre-transfer roller shown in FIG. 2; FIG. 3 (b); two points in the bearing portion shown in FIG. 3 (a). Perspective cross-sectional view showing a cross section taken along a plane indicated by a chain line

FIG. 4A is a side view of the plate-side frame on the near side as viewed from the front side in a state where the pre-transfer roller is not mounted. FIG. 4B is a state in which the pre-transfer roller is mounted. FIG. 4 (c) is a side view of the front plate frame viewed from the front side. FIG. 4 (b) shows a state in which the bearing projection is pushed in with a force that overcomes the restoring force of the coil spring from the state shown in FIG. 4 (b). side viewed plate on the frame of the front side from the front side. Figure 4 (d); Figure 4, such bearing projections indicated by (b) Y ₁ -
Y ₂ arrow cross-sectional view

FIG. 5 is an explanatory view showing another example of the shape of the lower part of the support member, in which the near-side bearing protrusion, the coil spring, and the like of the near-side plate-like frame are viewed in accordance with the arrow Q shown in FIG. Arrow view in case

FIG. 6 is a configuration diagram illustrating an example of an image forming process of a conventional image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier main body 2 Photosensitive drum 2a Back side flange part 2b Front side flange part 3 Drive device 4 Driving spur gear 5 Drum side spur gear 6 Transmission spur gear 7 Roller before copying 7a Roller shaft 9 Front plate frame 10 Back plate frame 11, 12 Bearing 11a Support 11b Bearing projection 21 Front end 22 Front end 23 Step 24, 25 Notch groove 31 Notch 32 Coil spring

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hideo Fukuda 1-2-28 Tamazo, Chuo-ku, Osaka-shi, Osaka Mita Kogyo Co., Ltd. (56) References JP-A-5-313506 (JP, A) JP-A-5-313506 Hei 5-134573 (JP, A) Actually open Hei 3-53948 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/16 G03G 15/20 G03G 15/00 510 G03G 15/00 550

Claims (2)

(57) [Claims] And 1. A cutout portion is formed plate-like frame, rotatably supports the rollers has a groove portion freely fitted or disconnect the edges of the notch, "to" substantially
A support member having a shape bent in the shape of , when the groove is fitted to the edge of the notch,
An elastic body provided on the plate-shaped frame, the elastic body being in contact with at least a lower portion of the support member and always lifting the support member elastically. 2. The image forming apparatus according to claim 1, wherein the roller is a roller that conveys the sheet to the fixing device side.
The roller device according to claim 1, wherein the elastic member is provided on an upstream side of a transfer device that transfers an image to the sheet, and the elastic body is a spring member.