JPH10232519A - Automatic document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily execute the operation of exchanging a carrying belt and positioning a belt unit. SOLUTION: In this automatic document feeder in an image forming device constituted so that one belt unit consists of the carrying belt 4 for carrying a document, plural supporting rollers 3 for rotatably supporting the carrying belt 4 and a supporting frame freely rotatably supporting these supporting rollers 3 and is detachably attached to a device main body, the supporting rollers 3 are freely rotatably attached to a tensile force applying belt 16 which is slidably fitted to the main body of the belt unit, in the direction of extending the belt and a cam 18 abutted on the tensile force applying bracket 16, for moving it is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an automatic document feeder in an image forming apparatus such as an electrophotographic copying machine.

[0002]

2. Description of the Related Art For example, in an electrophotographic copying machine,
In order to increase the efficiency of the copying operation, an automatic document feeder that sequentially feeds a document onto a platen glass is used. The automatic document feeder is provided with a transport belt that transports the paper along the surface of the platen glass, but becomes dirty or deteriorated when used for a long time. For this reason, it is necessary to periodically replace the transport belt, but in the conventional automatic document transport apparatus, there is a problem that it takes time to replace the transport belt.

FIGS. 8, 9 and 10 are a schematic sectional view, a schematic plan view of a main part and a schematic side view of a main part showing an example of a conventional automatic document feeder. The automatic document feeder A is provided so as to freely open and close the upper surface of the copying machine main body B.
The apparatus main body C of the automatic document feeder A includes a document feed roller 32 for feeding out a document 31 placed on the upper surface of the apparatus main body C, and a document 31 fed by the document feed roller 32. Document feed roller 3 for transporting onto platen glass 33 provided on the upper surface
4, a transport belt 4 for transporting the original on the platen glass 33, an original receiver 35 from which the copied original is discharged, and the like.

The transport belt 4 is rotatably supported by a drive-side support roller 2, a tension-side support roller 3, and a belt roller 36. The drive-side support roller 2 is directly rotatably mounted on the support frame 37, and rotational force is transmitted from the drive device 15 via a drive gear 38. On the other hand, the tension side support roller 3 is rotatably mounted on a tension applying bracket 39, and the tension applying bracket 39 includes a bracket fixing screw 40.
Is fixed to the support frame 37. The belt roller 36 is rotatably attached to the support frame 37.

The support frame 37 is fixed to the apparatus body frame 43 by a unit fixing screw 41. At this time, the positioning of the support frame 37 with respect to the apparatus main body frame 43 is performed by positioning the positioning pins 42 provided on the support frame 37 side.
This is performed by fitting into a positioning hole formed on the side.

A belt unit 44 is constituted by the support frame 37, the belt roller 36 attached to the support frame 37, and the like.

A front cover 45 is fixed to the apparatus body frame 43 by a cover fixing screw 46 so as to cover the front surface of the belt unit 44, and a cover 47 is formed so as to cover the other side surface and the upper surface of the belt unit 44. Are fixed by a cover fixing screw 48.

In the conventional automatic document feeder shown in FIGS. 8, 9 and 10, when the transfer belt 4 is replaced,
Loosen the screws 46 and 48 and remove the two covers 45 and 4
Remove 7

Next, the belt unit 44, which comprises the conveyor belt 4 and the drive-side support roller 2 and the tension-side support roller 3 and the support frame 37, is loosened by loosening three screws 41 and three. Remove from

In order to replace the conveyor belt 4, one of the support rollers 3 supported by a tension applying bracket 39 fixed to a support frame 37 by a bracket fixing screw 40 is further rotated by the screw 40 (front and rear sides of the apparatus). ) Is loosened to remove the transport belt 4 in the axial direction of the driving-side support roller 2 and the tension-side support roller 3 in a state where the belt tension is eliminated. The assembling is performed in the reverse order, but the fixing of the tension applying bracket 39 for applying tension to the belt 4 is performed as follows.
The belt 4 is held in tension and stopped by the bracket fixing screw 40.

The positioning of the belt unit 44 is as follows.
The two positioning pins 42 on the unit side are inserted into the positioning holes of the apparatus main body frame 43 on the apparatus main body C side, and are fixed by the unit fixing screws 41.

[0012]

As described above, in the conventional automatic document feeder, since the work of replacing the transfer belt 4 and positioning the belt unit 44 is complicated, the maintenance work time is reduced to 5 to 5. There was a problem that it took 10 minutes. Further, there is a problem that a work space for placing the removed unit is required.

[0013] Japanese Utility Model Publication No. 8-3398 discloses that one belt supporting roller and a belt roller are formed as a unit so that the transfer belt can be easily replaced, and a swing center shaft provided on a supporting frame. At the time of belt replacement, remove the belt unit from the automatic document feeder main body, remove the fixing screw, and swing the roller unit around the swing center, Although it is disclosed that the belt is replaced, the technique disclosed in the same publication also requires the belt unit to be separated from the apparatus main body to loosen the belt tension, and thus has the same problem as the above technique. there were.

Accordingly, an object of the present invention is to make it possible to easily carry out the work of replacing the conveyor belt and positioning the belt unit.

[0015]

According to the present invention, there is provided a transport belt for transporting a document, a plurality of support rollers for rotatably supporting the transport belt, and a support frame for rotatably supporting these support rollers. In an automatic document feeder in an image forming apparatus in which the unit is detachably attached to an apparatus main body, one of the plurality of support rollers slides in a belt stretching direction with respect to the unit main body. The tension applying bracket is rotatably attached to the tension applying bracket which is attached so as to be capable of moving the tension applying bracket in contact with the tension applying bracket.

[0016]

The means for moving the tension applying bracket may be a cam which is attached to a rotating shaft and abuts against the tension applying bracket, or the unit for disposing the unit at an operating position of the apparatus main body. It can be a cam provided on the apparatus main body side that comes into contact with the tension applying bracket.

Further, positioning means for engaging the unit and automatically positioning the unit with respect to the apparatus main body when the unit is disposed at the operating position of the apparatus main body may be further provided.

Further, the positioning means can be constituted by a positioning pin formed on the unit side and a positioning hole formed on the apparatus body side into which the positioning pin is inserted.

Further, it is desirable that the driving device provided on the apparatus main body side and the rotating member provided on the unit side are connected via power transmission means which can be separated and connected in the axial direction.

Further, in the present invention, a cover for covering the unit is provided, and a side of the cover on which the unit is attached / detached is a rotatable cover, and the rotatable cover is provided on an inner surface of the rotatable cover. A unit pressing means for pressing the unit toward the back of the apparatus main body when the cover is closed, and a lock mechanism for maintaining the rotatable cover closed.

Further, the present invention is characterized in that it has a guide member for pulling out the unit from the apparatus main body.

[0022]

1 and 2 are a plan view and a side view of a main portion of a partially cut-out portion showing an embodiment of an automatic document feeder according to the present invention. Members corresponding to those in the conventional example shown in FIGS. 8, 9 and 10 are denoted by the same reference numerals.

Rear-side support frame 1 arranged opposite
a and the front side support frame 1b, the drive side support roller 2 and the tension side support roller 3 are rotatably mounted, and the transport belt 4 is wound around the drive side support roller 2 and the tension side support roller 3. Have been. Positioning pins 5 and 6 are provided on the rear side support frame 1a and the front side support frame 1b, respectively, so as to protrude to the rear side of the apparatus main body. By fitting into positioning holes 7c and 7d formed in the rear vertical plate 7a and the front vertical plate 7b, respectively, the frame 7 is composed of support frames 1a and 1b, support rollers 2 and 3, a conveyor belt 4, and the like. The belt unit 8 is fixed while being positioned with respect to the apparatus body frame 7.

Between the rear vertical plate 7a of the apparatus body frame 7 and the front support frame 1b, the belt unit 8 can be pulled out in front of the apparatus body, that is, rightward in FIGS. For this purpose, there are provided two guide members 9 each composed of slide rails 9a and 9b slidably engaged with each other.

A part of the top plate 7d of the apparatus body frame 7 is
A body-side cover 10 that extends in the front-rear direction of the apparatus body and covers the rear and upper sides of the apparatus body frame 7 is screwed to the rear end 7e of the top plate 7d with screws 11. A rotating cover 13 is attached to the front end 7f of the top plate via a shaft 12.
Are rotatably mounted. This rotating cover 13
The unit pressing projection 13a which comes into contact with the front support frame 1b when the rotating cover 13 is closed
Is provided.

The transport belt 4 is rotatably supported by the drive side support roller 2 and the tension side support roller 3. The drive-side support roller 2 is directly rotatably mounted on the support frames 1a and 1b, and rotational force is transmitted from a drive device 15 via a coupling 14 including a pair of coupling halves 14a and 14b that mesh with each other. You. On the other hand, the tension side support roller 3 is rotatably attached to the tension applying bracket 16 as shown in FIGS. The tension applying bracket 16 is supported on the rear side by engaging a pin 1c protruding from the frame 1a with a guide elongated hole 16a formed in the tension applying bracket 16 and extending in the belt stretching direction. It is movably attached to the frame 1a in the belt stretching direction. Although not shown, the front side has a similar structure. An end of the tension applying bracket 16 on the side opposite to the support roller 3 constitutes a cam receiving portion 16b with which a cam 18 rotationally driven by a cam shaft 17 abuts.
The camshaft 17 is provided with a lever (not shown) for manual operation. Further, the camshaft 17 may be driven by a motor (not shown).

Next, in the automatic document feeder described above,
The operation when replacing the belt will be described.

First, as shown in FIG. 5, the rotating cover 13 is opened, and the belt unit 8 is pulled out along the guide member 9. In this state, as shown in FIG. 4A, the cam 18 is in contact with the cam receiving portion 16b of the bracket 16 for applying tension, and a predetermined tension is applied to the transport belt 4. Next, as shown in FIG. 4B, the camshaft 17 is manually operated by a lever (not shown) provided on the camshaft 17 or a motor (not shown) connected to the camshaft 17. ), The cam 18 is automatically rotated in the direction of arrow A so that the cam 18 does not come into contact with the cam receiving portion 16b of the bracket 16 for tension application. Thereby, the tension applying bracket 16 can be moved toward the drive-side support roller 2 along the guide elongated hole 16a, and the transport belt 4 is in a loosened state. Therefore, the transport belt 4 can be easily taken out. Then, in this state, after a new conveyor belt 4 is wound around the drive side support roller 2 and the tension side support roller 3,
By rotating the cam shaft 17 so that the cam 18 comes into contact with the tension applying bracket 16, a predetermined tension is applied to the transport belt 4.

During the above-mentioned work of replacing the conveyor belt 4,
Since the belt unit 8 is supported by the guide member 9 in a state where the belt unit 8 is pulled out from the apparatus main body, there is no need to place the belt unit 8 on a workbench.
Can be moved to a place where work is easy.

Next, when installing the belt unit 8 in which the conveyor belt 4 has been replaced into the apparatus main body, the belt unit 8 is pushed into the apparatus main body from the state shown in FIG. When the belt unit 8 is pushed into the inside of the apparatus main body, as shown in FIGS.
The positioning pins 5 provided on the front main body frame 7 are fitted into positioning holes 7c formed in the rear vertical plate 7a of the apparatus main body frame 7, and the positioning pins 6 provided on the front support frame 1b are connected to the front of the apparatus main body frame 7. Side vertical plate 7
The belt unit 8 is fitted in the positioning hole 7d formed in the main body frame 7b. Note that the tips of the positioning pins 5 and 6 are
It has a tapered shape so that it can be easily inserted into c and 7d.

Next, when the rotating cover 13 is closed, the unit pressing protrusion 13 formed on the inner surface of the rotating cover 13 is formed.
a, the belt unit 8 is pushed toward the back side of the apparatus main body, and the belt unit 8 is
Is fixed. Note that the rotating cover 13 is provided with a lock mechanism (not shown) for maintaining the closed state when the rotating cover 13 is closed.

When the belt unit 8 is mounted in the apparatus main body, the coupling 14 is in the engaged state, and the rotational force is transmitted from the driving device 15 to the driving support roller 2 via the coupling 14. Then, the transport belt 4 rotates.

In the example shown in FIG. 3 and FIG.
Although the conveyor belt 4 is loosened by using 8, other structures can be adopted.

FIG. 6 is a partially cutaway plan view showing another configuration example for loosening the transport belt when the transport belt is replaced. In the example shown in FIG. 6, a cam support member 19 is provided which extends in the axial direction of the conveyor belt 4 from the inner surface of the apparatus main body frame 7a on the back side, and the cam support member 19 has an inclined projecting toward the support roller 3 side. The cam 20 is attached.
The inclined cam 20 has an inclined surface inclined toward the support roller 3 toward the back of the apparatus main body.

On the other hand, the tension applying bracket 21 engages the pin 1a with a guide elongated hole 21a formed in the tension applying bracket 21 and extending in the belt stretching direction, similarly to the tension applying bracket 16. As a result, it is movably attached to the rear support frame 1a in the belt stretching direction. The end of the tension applying bracket 21 opposite to the support roller 3 is bent inward in the width direction of the conveyor belt 4 to form a cam receiving portion 21b which comes into contact with the inclined cam 20.

In the normal state, as shown in FIG. 6A, the cam receiving portion 21 of the tension applying bracket 21 is provided.
b is pushed by the inclined cam 20 in the direction of the support roller 3, and a predetermined tension is applied to the transport belt 4.

When the belt unit 8 is pulled out of the apparatus main body, as shown in FIG. 6B, the press-contact state of the inclined cam 20 and the cam receiving portion 21b is released, and the tension applying bracket 21 is moved to the guide slot 21a. Along with the drive-side support roller 2 so that the transport belt 4 is in a loosened state. Therefore, the transport belt 4 can be easily taken out.

In the above-described embodiment, a detachable coupling is used as a mechanism for transmitting a rotational force from the apparatus main body to the belt unit 8. However, as shown in FIG. A pair of gears 22a and 22b each having a curved surface at the end on the meshing side may be used in order to avoid collision between the tooth tips at the time of mounting.

[0039]

According to the present invention, the belt can be loosened by a simple operation such as turning the lever or attaching and detaching the belt unit without completely removing the tension applying bracket. And maintenance work can be performed easily in a short time.

Since the belt unit is automatically positioned by the mounting operation of the belt unit, manual positioning work is not required.

Further, since the belt unit can be taken out and fixed only by opening and closing the rotating cover, screwing work becomes unnecessary, and the work is extremely simplified.

Also, when the belt unit is pulled out of the apparatus main body, since the belt unit is connected to the apparatus main body, there is no need for a work space for placing the belt unit on the floor. The unit can be moved to a position where work can be easily performed.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a main part of a partially cutaway showing an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a main part showing an embodiment of the present invention.

FIG. 3 is a schematic plan view of a main part of a notch showing a belt tension applying mechanism in an embodiment of the present invention.

FIG. 4 is a schematic side view of a main part showing a belt tension applying mechanism according to the embodiment of the present invention.

FIG. 5 is an explanatory view showing a state in which the belt unit is pulled out from the apparatus main body in the embodiment of the present invention.

FIG. 6 is an explanatory diagram of another configuration example of the belt tension applying mechanism in the embodiment of the present invention.

FIG. 7 is an explanatory diagram of another configuration example of the drive transmission unit in the embodiment of the present invention.

FIG. 8 is a schematic sectional view showing a state of use of a conventional automatic document feeder.

FIG. 9 is a schematic plan view of a main part of a conventional automatic document feeder.

FIG. 10 is a schematic cross-sectional view of a main part of a conventional automatic document feeder.

[Explanation of symbols]

1a ... Rear side support frame, 1b ... Front side support frame, 1c ... Pin, 2 ... Drive side support roller, 3 ... Tension side support roller, 4 ... Transport belt, 5, 6 ... Positioning pin,
7: Device body frame, 7a: Rear vertical plate, 7b: Front vertical plate, 7c, 7d: Positioning hole, 8: Belt unit, 9: Guide member, 9a, 9b: Slide rail, 10: Body side cover, 11 ... screw, 12 ... shaft, 13
... Rotating cover, 13a ... Unit pressing projection, 14 ... Coupling, 14a, 14b ... Coupling half, 15 ...
Drive device, 16: Bracket for applying tension, 16a: Slot, 17: Cam shaft, 18: Cam, 19: Cam support member, 20: Inclined cam, 21: Bracket for applying tension, 2
1a: Guide slot, 21b: Cam receiving part

Claims (8)

[Claims] A transport belt for transporting a document, a plurality of support rollers for rotatably supporting the transport belt, and a support frame for rotatably supporting these support rollers are configured as a single unit. An automatic document feeder in an image forming apparatus detachably attached to an apparatus body, wherein one of the plurality of support rollers is slidably attached to a body of the unit in a belt stretching direction for tension application. An automatic document feeder, wherein the automatic document feeder is rotatably attached to a bracket, and is provided with means for moving the tension applying bracket by contacting the tension applying bracket. 2. The automatic document feeder according to claim 1, wherein the means for moving the tension applying bracket is a cam attached to a rotating shaft and abutting on the tension applying bracket. 3. The apparatus according to claim 2, wherein the means for moving the tension applying bracket is a cam provided on the apparatus main body side which comes into contact with the tension applying bracket when the unit is arranged at the operating position of the apparatus main body. 2. The automatic document feeder according to claim 1, wherein: 4. A positioning means for engaging with the unit when positioning the unit in the operating position of the apparatus main body and automatically positioning the unit with respect to the apparatus main body. 2. The automatic document feeder according to claim 1, wherein: 5. The positioning device according to claim 4, wherein the positioning means comprises a positioning pin formed on the unit side and a positioning hole formed on the apparatus body side into which the positioning pin is inserted. Automatic document feeder. 6. A driving device provided on the apparatus main body side and a rotating member provided on the unit side are connected via power transmission means which can be separated and connected in the axial direction. Item 2. The automatic document feeder according to Item 1. 7. A cover for covering the unit is provided, and a side on which the unit is attached / detached is a rotatable cover, and the rotatable cover is closed on an inner surface of the rotatable cover. 2. The apparatus according to claim 1, further comprising: a unit pressing unit that presses the unit toward the back side of the apparatus main body when the unit is pressed, and a lock mechanism that maintains the rotatable cover closed. Automatic document feeder. 8. The automatic document feeder according to claim 1, further comprising a guide member for pulling out the unit from the apparatus main body.