JPH10274311A - Drive control device, sheet feeding device, image forming device, and image reading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the unnecessary interference between a chipped gear and a second gear so as to stabilize the operation by providing a locking means for locking the chipped gear at a position, in which a chipped tooth part of the chipped gear and the second gear face to each other and gear surfaces thereof do not interfere with each other. SOLUTION: A chipped gear 4 is provided with a chipped cloth tooth part 4a and a claw 4b to be locked with a lock claw 11b. At a home position, the chipped tooth part 4a and a second gear 9 are positioned opposite to each other, and the claw 4b to be locked is locked with the lock claw 11b. When the rotation is started, lock of the lock claw 11b with the claw 4b to be locked is released, Sheets 1 are separated for feeding one by one by the rotation control of a feeding roller 2. Thereafter, at the time of carrying the sheet with a carrying means provided in the downstream, the feeding roller 2 is about going to be rotated by the friction force generated between the feeding roller 2 and the sheet 1 to be carried, but the claw 4b to be locked of the chipped gear 4 is locked by the lock claw 11b of a hook 11 so as to maintain the home position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for a drive control device using a toothless gear, and more particularly, for a sheet feeding device provided in an image forming apparatus such as a printer or a copying machine and an image reading apparatus such as an image scanner. The present invention relates to a drive control device.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus such as a copying machine and a printer, and an image reading apparatus such as an image scanner have been provided with a sheet feeding device.
In some cases, a drive control device that drives and controls the feed roller with a toothless gear is used.

FIG. 5 shows an example of this type of drive control device.

This is a perspective view showing a conventional feed roller drive control device.

Reference numeral 101 denotes a conveyed sheet (or sheet bundle), and reference numeral 102 denotes a feeding roller.
02 and a separation pad (not shown).
1 is fed while being separated one by one.

A drive control device for controlling the driving of the feed roller 102 includes a rotary shaft 103, a toothless gear 104 interlocked with the rotary shaft, an auxiliary gear 105 which always meshes with the toothless gear 104, and an auxiliary gear 105. The first gear 106 for transmitting the starting rotational force to the tooth gear, the second gear 109 for rotating the toothless gear started to rotate by the first gear in the same direction, and both the first and second gears mesh with each other. A planetary gear, a first gear 106, a second gear 109, an arm 108 connecting the three gear shafts of the sun gear 110, and a drive gear 107 for rotating the sun gear forward and backward freely. ing.

[0007] With this configuration, sheet feeding is performed as follows.

First, the driving gear 107 rotates clockwise, the sun gear 110 rotates counterclockwise, and the first gear 106 and the second gear 109 rotate clockwise. At the same time, the arm 108 rotates counterclockwise around the axis of the sun gear due to friction with the sun gear.

As a result, the first gear 10 connected to the arm
6 meshes with the auxiliary gear 105, and after the rotation direction is reversed by the auxiliary gear 105, applies a clockwise rotational force to the toothless gear 104.

As soon as the toothless portion of the toothless gear 4 comes out of the position facing the gear 9, that is, the home position, by the initial rotation force, the gear 7 starts to reversely rotate counterclockwise immediately. Then, the arm 108 rotates clockwise, the second gear 109 meshes with the toothless gear 104, and the toothless gear 104 rotates until it returns to the home position again.

By these operations, the feeding roller 102
Is intended to realize a rotation control of a predetermined angle (360 ° in the case of the figure).

[0012]

However, in the above prior art, the second gear 109 is provided with the toothless gear 104.
When returning to the home position after meshing with
When the missing tooth portion 04 comes to a position completely opposed to the second gear 109 (a position where the mutual tooth surfaces do not interfere with each other), the missing tooth gear 1
There was no guarantee that 04 would stop.

That is, the second gear 109 and the toothless gear 10
When the sheet 4 is located at the home position and the sheet 1 is being conveyed, the rotational force due to the frictional force generated between the feed roller 102 and the sheet 101 acts on the toothless gear 104,
The toothless gear 104 rotates, and the home position cannot be maintained. That is, the feed roller 102
In addition, the toothless gear 104 associated therewith rotates together.

In this case, the toothless gear 104 rotates beyond the home position, and the tooth surface of the second gear 109 and the tooth surface of the toothless gear 104 interfere with each other. The problem had arisen.

Also, the second gear 109 to the missing gear 104
On the other hand, when the rotation resistance of the rotary shaft 103 is large (heavy), the rotation is stopped at a position where the rotational force enough to rotate the toothless gear 104 and the rotary shaft 103 (including the feed roller 102) cannot be transmitted. When a large transport load is applied to the sheet 101 for some reason, the missing gear may stop at a position where the sheet 101 cannot completely reach the home position.

Also in this case, the tooth surface of the second gear 109 and the tooth surface of the toothless gear 104 interfere with each other, causing a problem that sound is generated or, in a severe case, the tooth surface of the gear is destroyed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to eliminate unnecessary interference between a toothless gear and a second gear and to stabilize operation. It is another object of the present invention to provide a high-quality drive control device.
Another object of the present invention is to provide a high-quality sheet feeding device, an image forming device, and an image reading device using the drive control device.

[0018]

According to the present invention, there is provided a toothless gear for transmitting rotation of a drive source to a rotary shaft by a predetermined angle, a standby position, and a stationary toothless gear. A first gear that can move between two positions, i.e., an initial rotation position that applies an initial rotational force to the first gear, and a second gear that starts meshing with the partial gear by rotation of the partial gear by the initial rotational force of the first gear.
And the first and second gears are used to convert the toothless gear from a position where the toothless part faces the second gear to a position where the toothless part next faces the second gear. In the drive control device for rotating, the locking means for locking the toothless gear at a position where the toothless part of the toothless gear and the second gear face each other and the tooth surfaces of both gears do not interfere with each other is provided. It is characterized by.

The locking means may lock in conjunction with the movement of the first gear.

In particular, the locking means may be locked or released using the moving force of the first gear.

The locking means may release the locking by moving the first gear to the start rotation position.

It is preferable that the locking means include an engaging portion that engages with the shaft of the first gear and a locking claw that locks the toothless gear.

The locking means may release the locking using the rotational force of the first gear.

In particular, the locking means may release the locking by rotation of the first gear at the time of starting rotation.

It is preferable that the locking means includes a gear portion that meshes with the first gear and a locking claw that locks the toothless gear. Further, the locking means includes biasing means for rotating the toothless gear from a position where the toothless portion of the toothless gear and the second gear face each other to a position where the tooth surfaces of both gears do not interfere with each other. I do.

On the other hand, the first gear is a planetary gear, and it is preferable that the first gear moves between the start rotation position and the standby position by planetary movement around the sun gear.

The second gear, like the first gear, is a planetary gear that planetarily moves around the sun gear.
The shafts of the gear and the sun gear are connected by one arm. When the second gear is in the starting rotation position, the first gear is in the non-meshing position with the toothless gear, and the second gear is in the standby position. It is also preferable that the two gears work together so that the first gear is in the meshing position with the toothless gear at the time.

It is also preferable that the planetary movement is performed by rotating a sun gear.

The locking means may be provided integrally with the arm.

In the sheet feeding apparatus, it is preferable that a feeding roller is provided on a rotation shaft of the drive control device, and the sheet is fed by rotating the feeding roller by a predetermined angle.

There is also provided an image forming apparatus having a sheet feeding section having the above-mentioned sheet feeding apparatus, and an image forming section for forming an image on a sheet fed by the sheet feeding section. It is suitable.

It is also preferable that the image reading apparatus has a document feeding section provided with the above-mentioned sheet feeding apparatus, and an image reading section for reading an image of the document fed by the document feeding section. is there.

[0033]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, shape, relative arrangement, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

(Embodiment 1) A drive control device according to a first embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a perspective view of the case where the drive control device is used in a sheet feeding device. FIG. 1 shows a drive control device according to the present embodiment except for the sheet 1 and the feed roller 2. Device. The configuration will be described below.

Among them, 3 is a rotary shaft for outputting a drive controlled by the drive control device, 4 is a toothless gear that is interlocked with the rotary shaft 3 and transmits rotation to the rotary shaft 3 as it is,
Reference numeral 5 denotes an auxiliary gear disposed at a position that always meshes with the toothless gear 4, reference numeral 6 denotes a first gear that transmits an initial rotational force to the toothless gear via the auxiliary gear, and reference numeral 9 denotes a toothless member that has started rotating by the first gear. The second gear 10 for rotating the gear in the same direction, and the first gear 10
A sun gear meshing with both the gear 6 and the second gear 9 and using both gears as planetary gears; 8 is an arm connecting the three gear shafts of the first gear 6, the second gear 9 and the sun gear 10; Reference numeral denotes a driving gear as a driving source for rotating the sun gear in the forward and reverse directions.

Reference numeral 11 denotes a hook, an engaging portion 11a for engaging the shaft of the first gear, a locking claw 11b for locking the toothless gear, and a shaft serving as a fulcrum of the operation of the hook 11. 1
1c.

On the other hand, the toothless gear has a toothless portion 4a and a locked claw 4b locked by the locking claw 11b.
The locking claw 11b and the locked claw 4b constitute locking means. With the drive control device having the above configuration, drive control and sheet feeding are performed as follows.

First, as a home position, the toothless portion 4a of the toothless gear 4 and the second gear 9 are located at positions facing each other.
The locking claw 11b has locked the locked claw 4b.

At the start of rotation, an input is made from outside to rotate the drive gear 7 clockwise.

When the driving gear 7 rotates clockwise, the sun gear 10 rotates counterclockwise, and the first gear 6 and the second gear 9 rotate clockwise. At the same time, the arm 8 rotates counterclockwise around the axis of the sun gear due to friction with the sun gear.

Thus, the first gear 6 connected to the arm 8
Moves obliquely upward to the right in the figure, and the engaging portion 11a of the hook 11 that engages with the shaft of the first gear 6 is also urged upward. As a result, the entire hook 11 rotates clockwise about the shaft 11c, and the locking between the locking claw 11b and the locked claw 4b is released. At the same time, the first gear 6 moves to the start-rotation position, that is, the position where the first gear 6 meshes with the auxiliary gear 5, and after the rotation direction is reversed by the auxiliary gear 5, applies a clockwise start-rotation force to the toothless gear 4.

As soon as the toothless portion of the toothless gear 4 comes out of the position facing the gear 9, that is, the home position, by the initial rotation force, the gear 7 starts to reversely rotate counterclockwise immediately. The arm 8 rotates clockwise, the first gear 6 moves to the standby position, the second gear 9 meshes with the toothless gear 4, and the toothless gear 4
Is rotated by the second gear 9 until it returns to the home position again.

With these operations, rotation control of the feed roller 2 at a predetermined angle (360 ° in the case of the drawing) is realized.
The sheet is separated and fed one by one by passing through a nip between a separation sheet (not shown) and a feeding roller.

Thereafter, the sheet may be further conveyed by conveying means provided further downstream, and at this time, the feeding roller 2 tries to rotate with the sheet 1 being conveyed due to frictional force generated between the sheet and the sheet. , The locked claw 4b of the toothless gear 4
The home position can be maintained by locking the locking claw 11b of the hook 11. That is, the rotation of the feed roller 2, the rotating shaft 3, and the toothless gear 4 can be suppressed, and interference between the tooth surface of the toothless gear 4 and the tooth surface of the second gear can be prevented.

The hook 11 may be rotated by interlocking the arm 11 with the engaging portion 11a of the hook 11 to lock and release the claw.

The above-described sheet feeding apparatus can be applied to an image forming apparatus or an image reading apparatus.

In this case, by providing a sheet feeding section provided with the sheet feeding apparatus of the present application and an image forming section for forming an image on the sheet fed from the sheet feeding section, the sheet feeding section is provided. A high-quality image forming apparatus capable of performing stable sheet feeding in the feeding section can be provided.
It should be noted that a portion other than the sheet feeding portion, such as an image forming portion provided in the image forming apparatus, may be appropriately applied with a conventional configuration, and a detailed description thereof will be omitted.

Similarly, according to the provision of the document feeder provided with the sheet feeder and the image reading section for reading the image of the document fed from the document feeder, the document feeder is also provided. It is possible to provide a high-quality image reading apparatus capable of performing stable feeding of a document in the feeding unit. In this case as well, the portions other than the document feeding section may appropriately apply the conventional configuration.

(Embodiment 2) FIG. 2 is a perspective view of a drive control device according to a second embodiment of the present invention used in a sheet feeding device.

In the first embodiment, the hook 11 is provided as the locking means. However, in this embodiment, a locking portion 8a is provided as a locking means on a part of the arm 8, and the tooth missing portion is provided. Gear 4
And the locked claw. That is, at the start of rotation, the arm 8 itself rotates counterclockwise about the axis of the sun gear 10, so that the second gear 9
The locking portion 8a provided on the side releases the locking with the locked claw 4b, and at the same time, the first gear 6 moves to the start rotation position to rotate the toothless gear 4. Thereafter, the first gear 6 immediately returns to the standby position, and the toothless gear 4 is rotated by the second gear 9 until the toothless portion 4a comes to a position facing the second gear 9 as shown in the figure. At the same time, the locking portion 8a locks the locked claw 4b to prevent the sheet 1 from rotating the feed roller 2, the rotating shaft 3 and the toothless gear 4.

Other configurations and operations are the same as those of the first embodiment, and therefore, the same components will be denoted by the same reference characters and description thereof will be omitted.

According to this embodiment, it is not necessary to provide a hook as a separate member, the number of parts and the number of assembling steps can be reduced, and an improvement in productivity can be achieved as compared with the first embodiment.

(Embodiment 3) FIG. 3A is a perspective view of a drive control device according to a third embodiment of the present invention used in a sheet feeding device, and FIG. FIG. In the above-described first embodiment, the hook 11 that releases the lock using the moving force of the first gear 6 is provided as the locking means, but in the present embodiment, the rotation of the first gear 6 A hook 12 is provided for releasing the lock using force.

The hook 12 is provided coaxially with the auxiliary gear 5 and is provided at a position where it can mesh with the first gear 6 and has a gear portion 12a having an outer diameter slightly larger than the auxiliary gear, and a locking claw 12b.
The locking claw 12b is configured to lock with the locked claw 4b of the toothless gear 4. The hook 12 is provided rotatably about a shaft 12c,
It is constantly urged in a clockwise rotation direction by an unillustrated urging member (for example, an elastic member such as a spring).

With this configuration, the arm 8 can be used at the start of rotation.
Rotates counterclockwise about the sun gear 10 axis,
First, the first gear 6 meshes with the gear portion 12a of the hook 12 to rotate the hook 12 counterclockwise against the urging force of the urging member. Thereby, the locking between the locking claw 12b and the locked claw 4b is released (a chain line in FIG. 3B). Next, the meshing between the first gear 6 and the gear portion 12a is disengaged by the counterclockwise rotation of the hook 12, the first gear 6 moves to the start rotation position, meshes with the auxiliary gear 5, and the toothless gear 4 To rotate. Thereafter, the first gear 6 immediately returns to the standby position, and the toothless gear 4 is rotated by the second gear 9 until the toothless portion 4a comes to a position facing the second gear 9 as shown in the figure. Then, the locking claw 12b returned to the original position by the urging force
Locks the claw 4b to prevent the sheet 1 from rotating the feed roller 2, the rotating shaft 3, and the toothless gear 4.

Other structures and operations are the same as those of the first embodiment, so that the same components are denoted by the same reference characters and description thereof is omitted.

According to the present embodiment, since the operation of the hook is performed by the meshing of the gears, the transmission rate of the force is good, and
The hook can be operated reliably.

(Embodiment 4) FIG. 4 (a) is a perspective view of a drive control device according to a fourth embodiment of the present invention used in a sheet feeding device, and FIG. (C) is an enlarged perspective view of the toothless gear 4 as viewed from above.

In the first to third embodiments, the external rotating force acting on the toothless gear 4 due to corotation or the like is supported by the locking means, and the toothless portion of the toothless gear and the second gear face each other. In this invention, the position where the tooth surfaces of both gears do not interfere with each other is set as the home position. On the other hand, when the rotational resistance of the rotating shaft 3 is large (heavy), or when a large transport load is applied to the sheet 1 for some reason, the sheet 1 is missing at a position where it cannot completely reach the home position. Sometimes the toothed gear stopped.

Therefore, in the present embodiment, as a preventive measure, the locking means according to the third embodiment is moved from the position where the toothless portion of the toothless gear and the second gear face each other, to the teeth of both gears. An urging means for rotating the toothless gear to a position where the surface does not interfere is provided.

Here, the urging means is mainly a C-shaped washer-shaped member shown as 4c in FIG.
In particular, as shown in FIG. 4C, the locked claw 4b is arranged so as to be located substantially at the center of the groove 4d of 4c. Further, both ends 4e and 4f of 4c are slopes, and the slope 4e on the downstream side in the rotation direction of the toothless gear 4 is the slope 4f on the upstream side.
The slope is steeper than that.

On the other hand, the hook 12 has substantially the same structure as that of the third embodiment, but is provided so as to be movable in the axial direction. It is always pressed.

With such a configuration, the urging means operates as follows. In FIG. 4C, the relative position of the locking claw 12b with respect to the toothless gear 4 is indicated by a chain line for convenience.
(Actually, the toothless gear 4 rotates in the direction of arrow B.) At the home position, as in the above-described embodiment, the locking claw 12b and the locked claw 4b abut to engage the toothless gear 4. In a stopped state (FIG. 4A,
(B) solid line, (c) chain line α).

When the arm 8 rotates counterclockwise about the axis of the sun gear 10 at the start of rotation, first, the first gear 6 and the gear portion 12a of the hook 12 mesh with each other, and the urging force of the urging member is applied. The hook 12 is rotated counterclockwise against the above. Thereby, the locking between the locking claw 12b and the locked claw 4b is released (a chain line in FIG. 4B, a chain line β in FIG. 4C).

Further, when the hook 12 rotates counterclockwise, the meshing between the first gear 6 and the gear portion 12a is released, and the first gear 6 moves to the start rotation position, and the auxiliary gear 5
To rotate the toothless gear 4 (dotted line γ in FIG. 4C). Thereafter, the first gear 6 immediately returns to the standby position, and at the same time, the locking claw 12b returns to the locking position (the dashed line δ in the figure) by the clockwise urging force applied to the hook 12.

The toothless gear 4 is rotated by the second gear 9 until the next toothless part 4 a comes to a position facing the second gear 9. At this time, the locking claw 12b is pressed against the slope 4f against the urging force C.
(The chain line ε in the figure). That is,
4c functions as a cam for the locking claw 12b. On this occasion,
In order for the locking claw to move smoothly in the axial direction, the slope 4f
It is better to have a gentle slope.

The tooth surface 4g of the toothless gear 4 is the second gear 9
The slope 4e is disposed immediately below the position where the locking claw 12b exists in the state where it is barely in contact with the tooth surface of FIG. Thereby, the locking claw 12b is moved in the axial direction C along the slope 4e by the urging force C. on the other hand,
The toothless gear 4 is rotated to a position where the tooth surface 4g does not interfere with the tooth surface of the second gear 9 due to the B-direction component of the force applied by the urging force C to the slope 4e. In this case, the slope 4e
Is desirably so steep that the rotational force applied to the toothless gear 4 by the urging force C becomes sufficiently large.

When the toothless gear 4 is rotated by the urging means to a position where the tooth surface 4g and the tooth surface of the second gear 9 do not interfere with each other, the locking claw 12b locks the locked claw 4b and the seat 1 prevents the feed roller 2, the rotating shaft 3 and the toothless gear 4 from rotating together.

The other configuration and operation are the same as those of the third embodiment, so that the same components are denoted by the same reference characters and description thereof is omitted.

According to the present embodiment, the toothless portion of the toothless gear and the second gear surely face each other and the tooth surfaces of both gears do not interfere with each other irrespective of the transport load or the like. The toothless gear can be locked, and drive control can be stably performed.

[0072]

As described above, according to the present invention,
There is no unnecessary interference between the toothless gear and the second gear, and a high-quality drive control device with stable operation can be provided. Further, it is possible to provide a high-quality sheet feeding device, an image forming device, and an image reading device using the drive control device.

[Brief description of the drawings]

FIG. 1 is a perspective view of a drive control device according to a first embodiment of the present invention used in a sheet feeding device.

FIG. 2 is a perspective view of a drive control device according to a second embodiment of the present invention used in a sheet feeding device.

FIG. 3A is a perspective view of a drive control device according to a third embodiment of the present invention used in a sheet feeding device, and FIG. 3B is an end view of the drive control device as viewed in a direction A. is there.

FIG. 4 (a) is a perspective view of a drive control device according to a fourth embodiment of the present invention used in a sheet feeding device, FIG. 4 (b) is an end view of the drive control device viewed from a direction A, (C) is an enlarged perspective view of the toothless gear 4.

FIG. 5 is a perspective view of a conventional drive control device used in a sheet feeding device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 sheet 2 feed roller 3 rotating shaft 4 toothless gear 5 drive gear 6 first gear 7 drive gear 8 arm 9 second gear 10 sun gear 11, 12 hook

Claims (16)

[Claims] 1. A toothless gear for transmitting rotation by a drive source to a rotary shaft by a predetermined angle, a standby position, and an initial rotation position for applying an initial rotational force to a stationary toothless gear. A first gear that is possible, and a second gear that starts to mesh with the missing gear by rotation of the missing gear due to the rotational force of the first gear. A drive control device for rotating a tooth gear from a position where the missing tooth portion faces the second gear to a position where the next missing tooth portion faces the second gear, further comprising: A drive control device comprising a locking means for locking the toothless gear at a position where the two gears face each other and the tooth surfaces of the two gears do not interfere with each other. 2. The drive control device according to claim 1, wherein said locking means locks in conjunction with movement of said first gear. 3. The drive control device according to claim 2, wherein the locking means locks or releases the moving gear using a moving force of the first gear. 4. The drive control device according to claim 3, wherein the locking means releases the locking by moving the first gear to the start rotation position. 5. The locking means according to claim 1, wherein said locking means includes an engaging portion for engaging with a shaft of said first gear, and a locking claw for locking said toothless gear. 5. The drive control device according to 4. 6. The drive control device according to claim 2, wherein the locking means releases the locking by using a rotational force of the first gear. 7. The drive control device according to claim 6, wherein the locking means releases the locking by rotation of the first gear during start-up rotation. 8. The apparatus according to claim 6, wherein said locking means comprises a gear portion meshing with said first gear, and a locking claw locking said toothless gear. The drive control device according to any one of the preceding claims. 9. The urging means for rotating the toothless gear from a position where the toothless part of the toothless gear and the second gear face each other to a position where the tooth surfaces of both gears do not interfere with each other. The drive control device according to any one of claims 1 to 8, comprising: 10. The first gear is a planetary gear, and moves between the start rotation position and the standby position by planetary movement around a sun gear.
10. The drive control device according to any one of items 9. 11. The second gear, like the first gear,
A planetary gear that planetarily moves around the sun gear,
The respective axes of the first gear, the second gear, and the sun gear are connected by one arm. When the second gear is in the start-rotation position, the first gear is in a non-meshing position with the missing tooth gear. The drive control device according to claim 10, wherein when the two gears are in the standby position, the two gears are interlocked so that the first gear is in a meshing position with the toothless gear. 12. The drive control device according to claim 10, wherein the planetary movement is performed by rotating the sun gear. 13. The drive control device according to claim 11, wherein said locking means is provided integrally with said arm. 14. A driving control device according to claim 1, wherein a feed roller is provided on a rotating shaft, and the sheet is fed by rotating the feed roller by a predetermined angle. A sheet feeding device. 15. A sheet feeding section provided with the sheet feeding apparatus according to claim 14, and an image forming section for forming an image on a sheet fed by the sheet feeding section. An image forming apparatus comprising: 16. A document feeder provided with the sheet feeder according to claim 14, and an image reading unit for reading an image of a document fed by the document feeder. Image reading device.