JP2001233472A - Paper feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems of conventional paper feeding devices with arm members supported at both end parts of a separate roller energized upward by a torsion spring wound around a metal rod provided close to the paper feeding device to cause a number of parts and a complicated structure resulting in generation of abnormal sound. SOLUTION: Around a separate roller core 58 provided between a separate roller 23 and a drive shaft 22, a torsion spring 72 to energize an arm 24 upward is wound, one end of the torsion spring 72 is locked to a spring lock part 24e of the arm 24, the other end is locked to a cover part 8a of an automatic paper feeding device 8 on which this paper feeding device 11 is installed, and the torsion spring 72 is disposed between a first gear 52 composing a gear train disposed on the outer side of the arm 24 and the arm 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder for separating stacked paper sheets one by one from an upper layer and transporting the separated paper to a lower side of the transport, comprising: a separate roller supported by a drive shaft;
The present invention relates to a sheet feeding device including an arm member swingably supported at both ends of the separate roller, and a pickup roller rotatably supported at the distal ends of the two arm members.

[0002]

2. Description of the Related Art Conventionally, a separate roller supported by a drive shaft, an arm member supported swingably at both ends of the separate roller, and a rotatable support at the distal ends of both arm members. A paper feeder including a pickup roller has been proposed, and is applied to, for example, a facsimile machine and an automatic document feeder mounted on a copying machine. The arm member of the paper feeding device is constantly urged upward, and the rotation of the drive shaft on which the separate roller is supported causes the arm member and the pickup roller to swing downward against this urging force. It is configured. As a means for urging the arm member upward, a torsion spring wound around a resin rod provided near the paper feeding device has been used.

[0003]

However, in a configuration in which a torsion spring is wound around a resin rod near the paper feeding device as described above, a rod member dedicated to the torsion spring is required, and the number of parts is large. Was also complicated. In some cases, a torsion spring is wound around the drive shaft of the separate roller.However, when the arm member and the pickup roller swing, the drive shaft is made of metal, so that the torsion spring rubs against the metal torsion spring. There is a problem that abnormal noise is generated. In view of the above, the present invention is to provide a sheet feeder in which the number of components is reduced and generation of abnormal noise when swinging a pickup roller or the like is suppressed.

[0004]

The present invention uses the following means in order to solve the above-mentioned problems in the paper feeding apparatus. That is, according to the first aspect of the present invention, a separate roller supported by a drive shaft, an arm member supported swingably at both ends of the separate roller, and a rotatable tip end of both arm members. In a paper feeder having a supported pickup roller, a torsion spring for urging the arm member upward is wound around a core member interposed between the separate roller and the drive shaft.

[0005] Further, in the invention according to claim 2, one end of the torsion spring is locked to the arm member, and the other end is locked to a casing side to which a sheet feeding device is attached.

According to a third aspect of the present invention, a gear train for transmitting a driving force from a drive shaft to a pickup roller is disposed outside one of the arm members, and the gear train and one of the arm members are arranged. And the torsion spring was arranged between them.

[0007]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing a facsimile apparatus equipped with the paper feeder of the present invention, FIG. 2 is a side sectional view of the same, FIG. 3 is a side sectional view showing an automatic paper feeder, and FIG. FIG. 5 is a plan sectional view of the same.

First, a schematic configuration of a facsimile apparatus to which the sheet feeding apparatus of the present invention is applied will be described with reference to FIGS. The facsimile apparatus F has a configuration in which a reading unit 2 is disposed above a recording unit 1, and the reading unit 2 is vertically rotatable with respect to the recording unit 1 about a rotation fulcrum 20.
The recording unit 1 includes a recording device 3 and a paper feed cassette 4 which are vertically arranged therein. After the paper deposited in the paper feed cassette 4 is fed to the recording device 3 for recording, a recording paper discharge tray 5 is provided. It is configured to discharge to

On the other hand, in the reading section 2, the reading device 6 is housed in a reading case 13 having a transparent stationary document mounting surface 14 having a transparent upper surface, and is placed on the stationary document mounting surface 14. The reading device 6 scans the read original, and the reading device 13 reads the original. Also, above the reading case 13, an original holding cover 7 that can be opened and closed around one side thereof is disposed. The original placed on the stationary original placing surface 14 is pressed from above by the holding cover 7.

At one end of the document holding cover 7, an automatic sheet feeding device (ADF device) 8 for automatically feeding a document is attached, and the automatic sheet feeding device 8 is controlled by a sheet feeding device 11 and a conveying device 12. It is configured. Then, the originals placed on the original supply tray 9 are picked up one by one by the paper feeder 11 of the automatic paper feeder 8, transported to one end of the stationary original placing surface 14 by the transporter 12, and read by the reading device. After reading the contents of the document, the document is discharged to a document discharge tray 10 formed on the upper surface of the document pressing cover 7.

That is, the reading unit 2 is used as a flat bed type scanner for scanning the reading device 6 to read a still original, and is a sheet feed type for reading while feeding the original with the reading device 6 fixed in position. It is configured so that it can be used as a scanner.

A key panel 15 is attached to one side of the reading case 13. By operating various operation keys of the key panel 15, the contents of the original are read, and the read contents are transmitted by facsimile. In this case, the destination is set, and the recording device 3 records the received contents and the read contents.

Next, the configuration of the automatic paper feeder 8 will be described. As shown in FIG. 3, a paper feeder 11 is disposed in an upper part of the automatic paper feeder 8, and the paper feeder 11 is rotatable by a drive shaft 22.
3, arms 24 and 25 provided on both sides of the separate roller 23 so as to be swingable (only the arm 24 is shown in FIG. 3), and a pick-up roller rotatably supported by the distal ends of the arms 24 and 25 26 etc.
A torsion spring 72 is fitted on the drive shaft 22, and one end of the torsion spring 72 is engaged with the arm 24, and the other end of the torsion spring 72 is provided with the sheet feeding device 11. Automatic paper feeder 8
Is locked to the cover portion 8a, which is a casing of the above. The torsion spring 72 urges the arm 24 upward, so that the arm 25 and the pickup roller 2
When the paper feed device 6 is urged upward and the paper feeding device 11 is stopped, the pickup roller 26 is rotated upward and is in a standby state. Separate roller 2
3 is in contact with a retard roller 31 urged toward the separate roller 23 side.

The automatic paper feeder 8 having the above-described configuration is used.
When the detecting unit (not shown) detects that the document D is stacked on the document feeding tray 9, the driving shaft 22 is driven to rotate. When the drive shaft 22 is rotationally driven, the drive shaft 22
With the rotation of, the separate roller 23 rotates in the direction of the arrow in FIG. 3, and the pickup roller 26 rotates downward against the urging force. When the pickup roller 26 rotates downward and comes into pressure contact with the upper surface of the document D, the pickup roller 26 stops rotating downward and starts rotating in the direction of the arrow. Then, by rotation of the pickup roller 26, the uppermost document D is fed out between the separate roller 23 and the retard roller 31, and is conveyed downstream.

In this case, until the document D is fed out between the separate roller 23 and the retard roller 31, the retard roller 31 rotates along with the separate roller 23 in the direction of transporting the document D to the downstream side. But
2 between the separate roller 23 and the retard roller 31
After more than one document D is inserted, the retard roller 3
Numeral 1 is configured so that the rotation direction is reversed and the document D is rotated in a direction of pushing the document D back to the document feed tray 9 side. Therefore, the second and subsequent originals D to be fed along with the uppermost original D conveyed downstream are the originals D to be conveyed.
The document is pushed back to the document feed tray 9 by the retard roller 31 rotating while sliding on the surface, and only the document D on the uppermost layer is separated and conveyed.

When the original D is conveyed by the feed roller 32, the original D is pulled, and the pulling force acts on the separate roller 23. When the pulling force of the document D acts, the separate roller 23 idles with respect to the drive shaft 22 because the one-way mechanism described later is incorporated in the separate roller 23. As a result of the rotation of the drive shaft 22 to the first gear 52 being cut off by the idle rotation, the lowering operation of the support arms 24 and 25 is stopped, and the support arms 24 and 25 are connected to the torsion spring 7.
By the force of 2, the pickup roller 26 swings around the drive shaft 22 in a direction to move up, and stops at a standby position corresponding to the next sheet (document D) feeding operation.

Further, the document D is conveyed in a paper feed path 36 by a feed roller 33 and passes over a document reading surface 35 formed of a transparent member such as glass. At this time,
The reading unit 6 reads the contents by the reading device 6 in the reading case 13, and then discharges the document to the document discharge tray 10 through the discharge conveyance path 37 by the discharge rollers 34 and 35.

When the rear end of the document D conveyed at a high speed by the feed roller 32 is conveyed downstream of the separation roller 23 and the retard roller 31, the rotation speed of the separation roller 23 is driven by the drive shaft 22. Then, the pickup roller 26 is rotated downward again to feed out the originals D stacked on the original supply tray 9 again, and thereafter, the above operation is repeated. Then, when all the originals D stacked on the original supply tray 9 are fed out and discharged to the original discharge tray 10, the automatic paper feeder 8 stops its operation. The transport device 12 includes a retard roller 31, feed rollers 32, 33, 34, and 35, a paper feed transport path 36, a discharge transport path 37, and the like.

Next, the paper feeder 11 mounted on the automatic paper feeder 8 configured and operated as described above will be described. As shown in FIG. 4, the drive shaft 22 includes an inner cylindrical body 51.
A separate roller 23, which comes into pressure contact with the retard roller 33, is rotatably fitted to the outside via a roller (shown in FIG. 5). The separate roller 23 includes a separate roller body 59 made of rubber, a soft synthetic resin, or the like, and an inner cylindrical body 51.
The separate roller core 58 and the separate roller main body 59 are configured to be integrally rotated by being press-fitted to a separate roller core 58 rotatably fitted to the outside.

One end 58 of the separate roller core 58
a (a right end in FIGS. 4 and 5), one end 51a of the inner cylinder 51 protrudes outward. Further, a clutch support member is provided outside the one end 51a of the inner cylinder 51. 6
6 are provided. The clutch support member 66 is externally fitted to the drive shaft 22, and is fixed in a rotational direction so as to rotate integrally with the drive shaft 22 by a fixing pin 65 fixed to the drive shaft 22.

A one-way clutch mechanism 47 is provided at one end of the separate roller 23 (right side in FIG. 5).
Is configured. The one-way clutch mechanism 47
The clutch support member 66 provided on the drive shaft 22,
A coil spring 67 having one end fixed to the clutch support member 66, one end 58a of a separate roller core 58 fixed to the other end of the coil spring 67, and an inner cylindrical body located on the inner peripheral side of the coil spring 67 51 and one end 51a. The winding direction of the coil spring 67 is such that the inner diameter is narrowed by the rotation of the clutch support member 66 in the document conveying direction, and the inner diameter is widened by the rotation of the separate roller 23, that is, the rotation of the separate roller core 58 in the document conveying direction. It has been. Further, the outer shape of the one end portion 51a of the inner cylinder 51 is formed smaller than the inner diameter of the coil spring 67 in a state where no external force is applied.

Accordingly, the rotation of the drive shaft 22 rotates the clutch support member 66 to reduce the inner diameter of the coil spring 67, and the inner peripheral surface of the coil spring 67 holds one end 51 a of the inner cylinder 51. The rotation of the drive shaft 22 is transmitted to the inner cylinder 51, and the first gear 52 is driven to rotate.

The base end of the arm 25 is rotatably fitted to a portion inside the one end 58a of the separate roller core 58 to which the coil spring 67 is fitted. That is, the shaft support hole 25 drilled at the base end of the arm 25
A separate roller core 58 is directly supported by the shaft a.

On the other hand, at the other end of the separate roller 23 (the left side in FIGS. 4 and 5), the other end 51b of the inner cylindrical body 51 projects outward of the separate roller 23, and The base end of the arm 24 is rotatably fitted to the other end 51 b of the arm 24 via the other end 58 b of the separate roller core 58. That is, the other end 58b of the separate roller core 58 is directly supported by the shaft support hole 24a formed in the base end of the arm 24. Also,
At the other end 51b of the inner cylinder 51, a first gear 52 is directly attached to the inner cylinder 51 at a portion outside the portion where the arm 24 is fitted, and is integrally rotatable. .

A pickup roller 26 is supported at the tip of the arms 24 and 25. The pickup roller 26 is configured by press-fitting a roller body 20 formed of rubber, soft synthetic resin, or the like to a cylindrical body 57, and is rotatably fitted to the rotating shaft 15. That is, the shaft support hole 24 drilled at the tip of the arm 24
The rotary shaft 45 is rotatably supported by the shaft b, and the cylindrical body 57 is rotatably supported by the shaft support hole 25b drilled at the tip of the arm 25.

The arm 24 and the arm 25 are connected by a connecting shaft 53, and the connecting shaft 53 is disposed between the separate roller 23 and the pickup roller 26. The connecting shaft 53 is formed integrally with the arm 25 and extends from the arm 25 toward the arm 24. A distal end 53 a of the connecting shaft 53 penetrates through the arm 24 and projects outside the arm 24. ing. By connecting the arm 24 and the arm 25 with the connecting shaft 53 in this manner, both the arms 24 and 25 can swing integrally about the drive shaft 22 and the both arms 24 and 25 Is improved in assembling stability. Thereby, the pickup roller 26 can be smoothly rotated while maintaining the parallel state with the drive shaft 22, and it is possible to suppress a one-sided contact when the pickup roller 26 comes into contact with the document D,
It is possible to prevent the skew of the document D and occurrence of a jam.

A second gear 54 is rotatably supported at the distal end 53a of a connecting shaft 53 projecting outward from the arm 24. The second gear 54 meshes with the first gear 52. I have. Further, the other end 45b of the rotating shaft 45 projects outward from the arm 24, and a third gear 46 is rotatably supported on the other end 45b integrally and rotatably.
6 meshes with the second gear 54.

The rotation of the third gear 46 is restricted by a torque limiter 61 provided between the arm 24 and the third gear 46. The torque limiter 61 has a recess 24f formed at the tip of the arm 24.
And an urging plate 63 slidably inserted into the recess 24f.
And a coil spring 62 interposed between the recess 24f and the urging plate 63, and a slip adjusting plate 64 made of felt or the like interposed between the urging plate 63 and the third gear 46. Have. That is, the urging plate 63 is pressed against the third gear 46 via the slip adjusting plate 64, and the rotation of the third gear 46 is restricted by the frictional force of the slip adjusting plate 64.

The third gear 46 is connected to the first gear 5
If the rotation driving force received from the drive shaft 22 via the second and second gears 54 is smaller than the rotation limiting force received from the torque limiter 61, the third gear 46 rotates around the rotation shaft 45. Instead, the arm 24 rotates so as to revolve around the first gear 52 to rotate the arm 24. Further, from this state, when the pickup roller 26 hits a sheet (such as the document D) on the document tray 9 and the rotation of the arm 24 is stopped and stopped, the third gear 46
1 receives a larger torque from the drive shaft 22 than the force for restricting the rotation received from the drive shaft 1.
Start to rotate around 5 centers.

A spring clutch 49 is formed at one end of the rotary shaft 45 (the end on the arm 25 side).
The spring clutch 49 includes a drive-side cylinder 68 fixedly rotatable integrally with the rotation shaft 45, and a cylinder 57 supported rotatably with respect to the drive-side cylinder 68 by the rotation shaft 45.
(The end on the arm 25 side) and a coil spring 69 connecting the drive-side cylinder 68 and the one end 57a of the cylinder 57. The coil spring 69
The inner diameter of the third gear 46 is reduced by the rotation of the third gear 46 in the document conveying direction, and the driving side cylinder 68 and one end 57a of the cylinder 57 are integrally rotatably connected to each other. The rotation of 46 is transmitted to the pickup roller 26. Conversely, the inner diameter of the coil spring 69 is increased by the rotation of the pickup roller 26 in the document conveying direction, the connection between the driving side cylinder 68 and the one end 57a of the cylinder 57 is cut, and the rotation of the third gear 46 is stopped. The transmission is not transmitted to the pickup roller 26.

Here, the arms 24 and 25
Is formed of a resin member having good lubricity such as polyacetal resin. A lubricating material or the like may be contained in the resin member having good lubricity to further improve the lubricity of the resin surface and enhance the slidability of the member in contact with the resin surface. Further, the connecting shaft 53, the inner cylinder 51, the separate roller core 5
8, the cylindrical body 57, the first gear 52, the second gear 54, the third gear 46, and other components of the sheet feeding device 11 may be similarly formed using a resin member having good lubricity.

As described above, by forming the arm 24 and the arm 25 constituting the sheet feeding device 11 with a resin member having a good lubrication, the arm 24 and the arm 25 can be formed without providing a bearing member such as a bearing. The separate roller core 58 is directly supported by the shaft support holes 24a and 25a,
Even when the rotary shaft 45 and the cylindrical body 57 are directly supported by the 4.25 shaft support holes 24b and 25b, smooth rotation performance of the separate roller 23 and the pickup roller 26 can be ensured. .

As described above, the gear train for transmitting the driving force from the drive shaft 22 to the pickup roller 26 is provided by the first gear 52, the second gear 54, and the third gear 5.
6, the first gear 52, the second gear 54, and the third gear 56 constituting the gear train are arranged outside the arm 24. In a conventional sheet feeding device, a gear train for transmitting a driving force from a drive shaft to a pickup roller is disposed inside an arm member that supports the pickup roller. In such a case, it is necessary to first remove the arm member, which makes the operation complicated. However, when the first gear 52, the second gear 54, and the third gear 56 constituting the gear train are attached and detached by disposing the gear train outside the arm 24 as in this example, the arm 24 and the like are used. Work can be performed without removing the gears 52 and 54.
The work of attaching and detaching the 56 can be easily and easily performed.

The first gear 52 constituting the gear train
A gap D is provided between the arm 24 and the separate roller core 58 supporting the arm 24.
The other end 58b of the second member extends to the gap D. A torsion spring 72 for urging the arm 24 upward is fitted around the other end 58b of the separate roller core 58 at the gap D. One end of the torsion spring 72 is locked by the spring locking portion 24e of the arm 24, and the other end is locked by the cover 8a of the automatic sheet feeding device 8 as described above.

As described above, the arm 24 is attached to the separate roller core 58 which is a core member interposed between the main body 59 of the separate roller 23 and the drive shaft 22.
By winding the torsion spring 72 for urging the torsion spring upward, it is not necessary to provide a rod member or the like for winding the torsion spring 72, and the number of parts of the sheet feeding device 11 can be reduced. The structure can be simplified. Further, since the separate roller core 58 around which the torsion spring 72 is wound is formed of a resin material having good lubrication, when the arms 24 and 25 and the pickup roller 26 swing, the separate torsion spring 72 and the separate roller core 58 are separated. Even if the roller core 58 slides, almost no noise is generated.

The torsion spring 72 has one end locked to the arm 24 and the other end locked to the cover 8a. First, the torsion spring 7
2 in a state where one end of the sheet feeding device 2 is locked to the arm 24,
1 to the automatic paper feeder 8, and then the other end of the torsion spring 72 may be engaged with the cover 8a of the automatic paper feeder 8. The assembly of the paper feeder 11 and the attachment of the torsion spring 72 may be performed. This can be easily and easily performed.

Further, by disposing the torsion spring 72 in the gap D between the first gear 52 and the arm 24 constituting the gear train, the structure of the sheet feeding device 11 can be simplified as a whole. Arm 2
4 can be stably and reliably urged upward.

Next, the sheet feeding device 11 configured as described above
Will be described with reference to FIG. As described above, in the sheet feeding device 11 in which the pickup roller 26 is rotated upward, the driving shaft 22 is driven by the driving motor.
Is driven to rotate, the inner diameter of the coil spring 67 of the one-way clutch mechanism 47 is reduced, and the inner peripheral surface of the coil spring 67 causes the one end 51 a of the inner cylinder 51 to move.
Is held, and the rotation of the drive shaft 22 is
And transmitted to the first gear 52, the separation roller 2
3 and the first gear 52 start rotating. In this case, the third gear 56 meshing with the first gear 52 and the second gear 54
The pickup arm 26 does not rotate because its rotation is restricted by the torque limiter 61, and the pickup arm 26 rotates downward around the drive shaft 22. When the downwardly rotated pickup roller 26 comes into pressure contact with the upper surface of the document D, the downwardly rotating operation of the pickup arm 26 stops.

When the rotation is stopped, a torque greater than the force received from the torque limiter 61 is transmitted from the drive shaft 22 to the third gear 56, and the third gear 56 starts rotating.
A rotation driving force is transmitted to the pickup roller 26 via the spring clutch 49 from the rotation shaft 45 that rotates integrally with the third gear 56. This pickup roller 26
, The uppermost sheet of the document D is fed between the separation roller 23 and the retard roller 33 on the downstream side.

As described above, when the fed original D is transported at a high speed by the further downstream feed roller 32, the separate roller 23 is pulled by the transported original D in a direction of increasing the rotation speed. . When the rotation speed of the separate roller 23 becomes high and the overfeed state occurs, the one-way clutch mechanism 47, which is a one-way clutch, rotates the separate roller core 58 more rapidly than the clutch support member 66 and the coil spring 67. Is loosened to increase the inner diameter, and the inner peripheral surface of the coil spring 67 is connected to one end 51a of the inner cylindrical body 51.
, And the transmission of the driving force to the separate roller 23 and the first gear 52 is interrupted. Then, the pickup roller 26 whose downward rotation power has been cut off rotates upward by the urging force of the torsion spring 72 and separates from the paper surface of the document D.

Thereafter, when the rear end of the document D conveyed at a high speed is conveyed downstream of the separation roller 23 and the retard roller 31, the separation roller 23
2, the pickup roller 26 is rotated downward again, and the document D stacked on the document supply tray 9 is fed out again. Thereafter, the above-described operation is repeated.

In this embodiment, an example in which the paper feeder 11 is applied to the facsimile machine F has been described. However, the present invention is not limited to this. It can also be applied to devices.

[0043]

According to the present invention, the following effects can be obtained by employing the above-described configuration in the paper feeding apparatus. First, a torsion spring for urging the arm member upward is wound around a core member interposed between the separate roller and the drive shaft as in claim 1. It is not necessary to provide a rod member or the like specially, so that the number of parts of the sheet feeding device can be reduced and the structure can be simplified. Further, by forming the core member around which the torsion spring is wound with a resin member having good lubrication, it is possible to suppress generation of abnormal noise when the arm member or the like swings.

Further, since one end of the torsion spring is locked to the arm member and the other end is locked to the casing side to which the paper feeding device is attached, the automatic paper feeding device of the paper feeding device is provided. And torsion springs can be easily and easily mounted.

Further, a gear train for transmitting the driving force from the drive shaft to the pickup roller is disposed outside the one arm member, and between the gear train and the one arm member. Since the torsion spring is disposed in the above, the structure of the sheet feeding device can be simplified as a whole, and the arm member can be urged upward stably and reliably.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a facsimile apparatus equipped with a sheet feeding device of the present invention.

FIG. 2 is a side sectional view of the same.

FIG. 3 is a side sectional view showing the automatic sheet feeding device.

FIG. 4 is a plan view showing a sheet feeding device.

FIG. 5 is a plan sectional view of the same.

[Explanation of symbols]

 Reference Signs List 8 Automatic paper feeder 8a Cover 11 Paper feeder 22 Drive shaft 23 Separate roller 24/25 Arm 24e Spring latch 26 Pickup roller 52 First gear 53 Connecting shaft 54 Second gear 56 Third gear 72 Torsion spring

Claims (3)

[Claims] 1. A separate roller supported by a drive shaft, an arm member swingably supported by both ends of the separate roller, and a pickup roller rotatably supported by the distal ends of both arm members. The paper feeding device according to claim 1, wherein a torsion spring for urging the arm member upward is wound around a core member interposed between the separate roller and the drive shaft. 2. The paper feeding device according to claim 1, wherein one end of the torsion spring is locked to the arm member, and the other end is locked to a casing to which the paper feeding device is attached. 3. A gear train for transmitting a driving force from a drive shaft to a pickup roller is arranged outside one arm member, and the torsion spring is arranged between the gear train and one arm member. The sheet feeding device according to claim 1 or 2, wherein