JPH09188426A - Sheet conveying device and image forming device - Google Patents

Abstract

(57) Abstract: The present invention makes it possible to provide a sheet conveying device capable of controlling the driving of a plurality of sheet conveying means by a single plunger, and an image forming apparatus including the same. Has an aim. A pick-up toothless gear 7 connected to a pickup roller 14 is drive-controlled by a toothless link 12 connected to a plunger 11, and a spring clutch mechanism 8 connected to a conveying roller 16 has a toothless link. It is characterized in that it is configured to be driven and controlled by a clutch link 18 interlocking with 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer and a facsimile machine, and more particularly to a sheet conveying apparatus equipped in the image forming apparatus.

[0002]

2. Description of the Related Art A conventional example of a sheet conveying device installed in an image forming apparatus such as a copying machine, a printer, a facsimile machine will be described with reference to FIGS. FIG. 14 is an explanatory plan view showing a configuration of a conventional sheet feeding mechanism, and FIG. 15 is a sectional explanatory view showing a configuration of a conventional sheet feeding mechanism.

14 and 15, a sheet feeding mechanism 101
When the rotational driving force is transmitted to the gear 102 by the drive transmission means (not shown), the gears 103 and 105 that mesh with the gear 102
The gears 104 and 106 meshing with the gears 103 and 105 are driven to rotate.

The rotational driving force transmitted to the gear 104 is transmitted to a sheet pickup mechanism 107 that rotationally drives a pickup roller 115 that feeds out a sheet S stored in a sheet storage means (not shown), and is transmitted to a gear 106. The force is transmitted to the sheet transport mechanism 108 that rotationally drives the transport roller 117 that transports the sheet S fed by the pickup roller 115.

In the seat pickup mechanism 107 in the initial standby state, the pawl 109b urged toward the partly tooth-missing gear 111 side by the pulling force of the spring 109a of the plunger 109.
Is integrally formed with the tooth-chipped gear 111, and is engaged with and stopped by a stopper 111a biased counterclockwise in FIG. 15 about the shaft 114 by the pulling force of the spring 110. The toothless portion of 111 is held so as to face the gear 104, so that the rotational driving force of the gear 104 is not transmitted to the toothless gear 111, and the pickup connected to the toothless gear 111 via the shaft 114. The roller 115 is also held in a stopped state.

At this time, in the sheet conveying mechanism 108,
The claw 112b, which is urged toward the clutch 113 by the pulling force of the spring 112a of the plunger 112, is locked by the stopper 113c that releases the tightening force of the spring 113b, and is transmitted from the gear 106 to the gear 113a of the clutch 113. The generated rotational driving force is cut off in the clutch 113 and is not transmitted to the output side of the clutch 113, and the conveyance roller 117 connected to the output side of the clutch 113 via the shaft 116 is also held in a stopped state.

The sheet feeding mechanism 10 configured as described above
When the command for feeding the sheet S is sent from the main body of the image forming apparatus (not shown) in 1, the electromagnet 109c of the plunger 109 is actuated, the pawl 109b is disengaged from the stopper 111a of the toothless gear 111, and the spring 110 Partial gear 11 due to pulling force
1 rotates in the counterclockwise direction in FIG. 15 about the shaft 114 so that the tooth portion of the toothless gear 111 and the gear 104 mesh with each other, and the gear 104
Is transmitted to the partly tooth-missing gear 111 and the pickup roller 115 having a half-moon shaped cross section is rotated via the shaft 114 to start feeding the sheet S.

Almost at the same time, the plunger 112
The electromagnet 112c of the clutch operates, the claw 112b is disengaged from the stopper 113c of the clutch 113, and the tightening force of the spring 113b is recovered, so that the gear 113
The rotational driving force of 106 is transmitted to the shaft 116 via the clutch 113, and the transport roller 117 is rotated via the shaft 116. Then, the sheet S fed out by the pickup roller 115 is nipped and conveyed by the conveyance roller 117 and the roller 118 which is in pressure contact with the conveyance roller 117.

[0009]

However, in the above-mentioned conventional technique, the plunger 109 for controlling the drive of the pickup roller 115 and the plunger 112 for controlling the drive of the conveying roller 117 are respectively provided. Since they are separately configured, there is a problem that the number of parts increases and the cost increases.

[0010] The present invention is to solve the above problems,
It is an object of the present invention to provide a sheet conveying device capable of controlling the driving of a plurality of sheet conveying means by a single plunger, and an image forming apparatus including the sheet conveying device.

[0011]

A typical configuration according to the present invention for achieving the above object is to control each sheet conveying operation by a plurality of sheet conveying means for conveying a sheet by one plunger. A sheet conveying device having the above-mentioned configuration.

In the above structure, the drive control of the plurality of sheet conveying means is performed by one plunger,
Unlike the conventional example, it is not necessary to provide a plurality of plungers corresponding to the individual sheet conveying means, and the number of parts can be reduced and the cost can be reduced.

Further, the first concrete of the sheet conveying device.
The configuration of the first sheet conveying means for conveying the sheet,
An idler gear, to which a driving force from a driving source is transmitted, in a sheet conveying device that is disposed on the downstream side of the first sheet conveying unit in the sheet conveying direction and includes a second sheet conveying unit that conveys a sheet, A toothless gear capable of engaging / disengaging with the idler gear, the first sheet conveying means connected to the toothless gear, and a first locking portion integrally provided with the toothless gear. A second locking portion integrally provided with the tooth-chipped gear, a first link lever that engages with the first locking portion to suppress rotation of the tooth-chipped gear, The second link lever that engages with the locking portion of No. 2 to suppress the rotation of the partly tooth-missing gear, the plunger that drives the first and second link levers, and the driving force from the driving source are transmitted. Installed on the output side of the spring clutch mechanism. Rotation of the spring clutch mechanism by interlocking with the second sheet conveying means thus provided and the first and second link levers and engaging with a third locking portion provided in the spring clutch mechanism. And a spring clutch control lever that suppresses the above.

According to the above-mentioned first specific structure, when the first and second sheet conveying means are in the standby state, the plunger is actuated to move the first link lever to the first link lever. The spring clutch control lever is engaged with and locked to the locking portion, and the spring clutch control lever is engaged with and locked to the third locking portion of the spring clutch mechanism to operate the first and second sheet conveying means. Hold in a stopped state.

Then, when the conveying operation of the first and second sheet conveying means is started, the plunger is actuated to disengage the first link lever from the first engaging portion and the tooth missing portion. The gear is rotated to mesh with the idler gear, the spring clutch control lever is disengaged from the third engaging portion of the spring clutch mechanism, and the tooth-chipped gear and the spring clutch mechanism are rotated to respectively rotate the first and the first clutch gears. Two
Drive the sheet conveying means.

When the toothless gear makes one full revolution,
The second link lever is engaged and locked with the second locking portion to stop the toothless gear and the first sheet conveying means, and the plunger is operated at a predetermined timing. The second link lever is disengaged from the second locking portion, and the first link lever is engaged and locked with the first locking portion to lock the toothless gear and the first seat. While maintaining the stopped state of the conveying means, at the same time, the spring clutch control lever is engaged and locked with the third locking portion of the spring clutch mechanism to lock the spring clutch mechanism and the second clutch mechanism.
Then, the sheet conveying means is stopped to return to the standby state.

The second concrete of the sheet conveying device
The configuration of the first sheet conveying means for conveying the sheet,
An idler gear, to which a driving force from a driving source is transmitted, in a sheet conveying device that is disposed on the downstream side of the first sheet conveying unit in the sheet conveying direction and includes a second sheet conveying unit that conveys a sheet, A toothless gear capable of engaging / disengaging with the idler gear, the first sheet conveying means connected to the toothless gear, and a first locking portion integrally provided with the toothless gear. A link lever that engages with the first locking portion and suppresses rotation of the toothless gear;
A plunger for driving the link lever, a spring clutch mechanism to which a driving force from a driving source is transmitted, the second sheet conveying means provided on the output side of the spring clutch mechanism, and the link lever. In addition, a spring clutch control lever that engages with a second locking portion provided in the spring clutch mechanism to suppress rotation of the spring clutch mechanism, and operates in conjunction with rotation of the spring clutch mechanism, The present invention is characterized by including a cam mechanism that controls the engagement operation between the spring clutch control lever and the second locking portion.

According to the above-mentioned second specific structure, when the first and second sheet conveying means are in the standby state, the plunger is actuated to move the link lever to the first locking portion. To lock the spring clutch control lever to the second locking portion of the spring clutch mechanism to lock the first and second sheet conveying means. Hold.

When the conveying operation of the first and second sheet conveying means is started, the plunger is actuated to disengage the link lever from the first engaging portion and rotate the tooth-chipped gear. And the idler gear are engaged with each other, the spring clutch control lever is disengaged from the second engaging portion of the spring clutch mechanism, and the tooth-chipped gear and the spring clutch mechanism are respectively rotated to rotate the first and second seats. Drive the transport means.

Then, the plunger is actuated at a predetermined timing before the tooth-missing gear makes one complete rotation to engage the link lever with the first locking portion to lock the tooth-missing tooth. The gear and the first sheet conveying means are stopped. The cam mechanism interlocked with the rotation of the spring clutch mechanism prevents engagement of the spring clutch control lever and the second locking portion of the spring clutch mechanism to operate the second sheet conveying means for a predetermined time. After that, at a predetermined timing, the engagement of the spring clutch control lever with the second locking portion of the spring clutch mechanism by the cam mechanism is released, and the spring clutch control lever moves to the first position of the spring clutch mechanism. The second clutch is engaged with and locked by the second locking portion, and the spring clutch mechanism and the second sheet conveying means are stopped to return to the standby state.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a sheet conveying device and an image forming apparatus having the same according to the present invention will be described with reference to the drawings. First, a first embodiment of a sheet conveying device according to the present invention will be described with reference to FIGS. 1 is an explanatory plan view showing a configuration of a first embodiment of a sheet conveying device according to the present invention, FIG. 2 is an explanatory cross-sectional view showing a configuration of the first embodiment, and FIGS. 3 to 6 are operations of the first embodiment. It is a figure explaining.

More specifically, in an image forming apparatus A shown in FIG.
The sheet feeding mechanism 1 shown in FIGS. 1 to 6 which constitutes a sheet conveying device that feeds out and conveys the sheet S accommodated therein is incorporated.

As shown in FIGS. 1 and 2, the sheet feeding mechanism 1 has various gear trains, which will be described later in detail, provided on the apparatus main body frame, and the sheets accommodated in the sheet cassette B are stored in the sheet cassette B. A pickup toothless gear 7 having a toothless portion is connected via a shaft 13 to a pickup roller 14 having a half-moon shape in cross section, which is a first sheet conveying means for feeding S and serves as a first conveying rotary member. There is.

Further, a conveying roller 16 which is a second sheet conveying means and serves as a second conveying rotary member is disposed on the downstream side of the pickup roller 14 in the sheet conveying direction (hereinafter, simply referred to as "downstream side"). The transport roller 16 is connected via a shaft 15 to the output side of a spring clutch mechanism 8 serving as clutch means.

A roller 17 that rotates in accordance with the rotation of the transport roller 16 is pressed against the transport roller 16, and the sheet S fed by the pickup roller 14 is nipped by the transport roller 16 and the roller 17. Are transported.

A tooth-missing gear cam 7a, which is provided integrally with the pickup tooth-missing gear 7, is arranged in the pickup tooth-missing gear 7, and the tooth-missing gear cam 7a is provided with a toothless gear serving as a first engaging portion. The tooth stopper 7c and the toothless provisional stopper 7b serving as the second locking portion are arranged with a predetermined phase difference.

Further, a toothless link 12 is provided adjacent to the pick-up toothless gear 7 so as to be rotatable about a rotary shaft 12c with respect to the apparatus body frame, and one end of the toothless link 12 is the apparatus body. The core 11a of the plunger 11 fixed to the frame
It is connected to.

A toothless link claw 12a, which serves as a second link lever, is provided at the other end of the toothless link 12 so that the toothless link 12 is actuated by the action of the plunger 11. The tooth link claw 12a can be engaged with the temporary tooth missing stopper 7b provided on the missing tooth gear cam 7a.

A clutch link 18 is provided adjacent to the pick-up toothless gear 7 and the spring clutch mechanism 8 so as to be rotatable about a rotation shaft 18d with respect to the apparatus main body frame. One end of the clutch link 18 is provided. 2 is engaged with the other end of a clutch link spring 19 whose one end engages with the apparatus main body frame, and the clutch link 18 is always centered around the rotating shaft 18d by the pulling force of the clutch link spring 19. It is biased counterclockwise.

At the other end of the clutch link 18, there is provided a clutch link connecting portion 18c which is connected to the toothless link connecting portion 12b at the other end of the toothless link 12, and these connecting portions 12b, 18c constitutes the first link lever,
A clutch link toothless pawl 18b is provided at the tip of the clutch link connecting portion 18c.

The clutch link tooth-missing pawl 18b can be engaged with the tooth-missing stopper 7c in accordance with the rotational movement of the clutch link 18 which is interlocked with the tooth-missing link 12 which is rotated by the action of the plunger 11. Has become.

A clutch link pawl 18a, which serves as a spring clutch control lever, is provided at the other end of the clutch link 18, and the toothless link 12 by the action of the plunger 11 and the rotation of the clutch link 18 interlocked therewith. Depending on the operation, the clutch link claw 18a can be engaged with the stopper 8b serving as a third locking portion that releases the tightening force of the control spring 8c built in the spring clutch mechanism 8.

A tooth-missing spring 10 whose one end is engaged with the apparatus main body frame is engaged with a predetermined position of the tooth-missing gear cam 7a fixed to the pickup tooth-missing gear 7. In the state where the toothless portion faces the pickup idler gear 4, the pickup toothless gear 7 is constantly urged in the counterclockwise direction in FIG. 2 about the shaft 13 by the pulling force of the toothless spring 10. .

In FIG. 2, when the rotational driving force is transmitted to the two-stage gear 2 from drive transmission means connected to a drive source (not shown), the two-stage gear 3 and the idler gear 5 meshing with the two-stage gear 2 rotate. The two-stage gear 3 and the idler gear 5, which are in mesh with the idler gear 5, are driven to rotate.

The pick-up idler gear 4 is arranged at a position where it can mesh with a pick-up tooth-missing gear 7 provided in a sheet pick-up mechanism for rotating and driving a pick-up roller 14 for feeding out the sheet S stored in the sheet cassette B. The pickup idler gear 4 and the pickup toothless gear 7 constitute clutch means for controlling the rotational drive of the pickup roller 14 which is the first sheet conveying means. Further, the transport idler gear 6 is
It meshes with a clutch gear 9 provided on the drive input side of a spring clutch mechanism 8 which is a clutch means.

The pickup roller 14 connected to the pick-up toothless gear 7 by the shaft 13 rotates integrally with the pick-up toothless gear 7 and feeds the sheet S stored in the sheet cassette B. In addition, the spring clutch mechanism 8 and the shaft
The conveyance roller 16 connected by 15 rotates integrally with the clutch control ring 8a, and cooperates with a roller 17 arranged in pressure contact with the conveyance roller 16 so that the sheet S fed by the pickup roller 14 is conveyed. Nip it and transport it further downstream.

As shown in FIG. 3, when the sheet feeding mechanism 1 is stopped and in the standby state, the core 11a of the plunger 11 whose operation is appropriately controlled by the control means C shown in FIG. 1 is at the pulled-out position. Yes, the clutch link connecting portion 18c of the clutch link 18 is biased counterclockwise in FIG. 3 about the rotation shaft 18d by the pulling force of the clutch link spring 19.
Pushes the missing tooth link connecting portion 12b of the missing tooth link 12 to urge the missing tooth link 12 in the clockwise direction of FIG. 3 around the rotation shaft 12c, and the clutch link missing tooth claw of the clutch link 18
18b is hooked and locked by a tooth-missing stopper 7c of a tooth-missing gear cam 7a provided on the pickup tooth-missing gear 7.

Then, the action of the tooth-missing spring 10 that pulls the tooth-missing gear 7 around the shaft 13 in the counterclockwise direction in FIG. 3 and urges the pickup tooth-missing gear 7 in the state shown in FIG. Retained.

At this time, the toothless portion of the pickup tooth-missing gear 7 faces the pickup idler gear 4, and the pickup toothless gear 7 and the pickup idler gear 4 are held in a non-meshing state, and the pickup toothless gear 7 The pickup roller 14 connected to is held in a stopped state.

At the same time, the clutch link spring
A clutch link claw 18a of the clutch link 18 that is pulled by 19 and is biased counterclockwise in FIG. 3 about the rotation shaft 18d is formed on the outer periphery of the clutch control ring 8a provided in the spring clutch mechanism 8. Control spring 8c which is built in the spring clutch mechanism 8 by being locked by the stopper 8b
Is loosened, and the rotational driving force from the clutch gear 9 provided on the drive input side of the spring clutch mechanism 8 is applied to the spring clutch mechanism 8.
Is not transmitted to the output side of the transport roller 16 and is connected to the output side of the spring clutch mechanism 8 and is held in a stopped state.

At this time, the toothless link claw 12a of the toothless link 12
Is retracted to the downstream side in the counterclockwise direction in FIG. 3 of the pick-up tooth-missing gear 7 with respect to the engagement portion of the tooth-missing temporary stopper 7b of the gear-missing gear cam 7a provided in the pick-up missing gear 7. 7 has a toothless gear cam 7a
The toothless temporary stopper 7b is detached.

Next, as shown in FIG. 4, when a command for feeding the sheet S is sent from the main body of the image forming apparatus A and the sheet feeding mechanism 1 is in the feeding state for feeding the sheet S. , The core 11a of the plunger 11 is pulled in the direction of the arrow a in FIG. 4, and the toothless link 12 connected to the core 11a is rotated in the counterclockwise direction in FIG. The tooth link connecting portion 12b pushes the clutch link connecting portion 18c in the direction of arrow b in FIG. 4 against the pulling force of the clutch link spring 19.

Then, the clutch link 18 is rotated in the clockwise direction in FIG. 4 about the rotating shaft 18d, and the clutch link tooth-missing pawl 18b is provided on the pickup tooth-missing gear 7 so that the tooth-missing gear cam 7a is missing. By being disengaged from the tooth stopper 7c, the pickup toothless gear 7 pulled by the toothless spring 10 rotates counterclockwise in FIG. 4 about the shaft 13, and the tooth portion of the pickup toothless gear 7 and the pickup. The idler gear 4 meshes. At this time, the toothless link claw 12a of the toothless link 12 abuts and slides along the outer peripheral surface of the toothless gear cam 7a.

With the above structure, the rotational driving force is transmitted from the pickup idler gear 4 to the pickup tooth-missing gear 7, and the pickup roller 14 connected to the pickup tooth-missing gear 7 via the shaft 13 is centered on the shaft 13. The sheet S accommodated in the sheet cassette B is fed out by rotating counterclockwise in FIG.

At the same time, the rotation axis of the clutch link 18
The clutch link pawl 18a is also disengaged from the stopper 8b of the spring clutch mechanism 8 by the clockwise rotating motion of FIG.
Is closed and the rotational driving force of the clutch gear 9 is transmitted to the conveying roller 16 connected to the output side of the spring clutch mechanism 8, the conveying roller 16 rotates, and the sheet S fed by the pickup roller 14 becomes the conveying roller 16. It is nipped and conveyed by the rollers 17.

As shown in FIG. 5, when the pick-up tooth-missing gear 7 makes one revolution, the tooth-missing link claw 12a sliding along the outer peripheral surface of the tooth-missing gear cam 7a temporarily moves to the tooth-missing gear cam 7a. The pick-up toothless gear 7 and the pick-up roller 14 stop rotating by being hooked on the stopper 7b.

At this time, the clutch link tooth-missing pawl 18b of the clutch link 18 is a drawing of the pickup tooth-missing gear 7 rather than the engagement portion of the tooth-missing gear cam 7a provided on the pickup tooth-missing gear 7 with the tooth-missing stopper 7c. 5 is retracted to the upstream side in the counterclockwise direction and separated from the tooth-chipped stopper 7c of the tooth-chipped gear cam 7a provided on the pickup tooth-chipped gear 7. At this time, the transport roller 16 continues to rotate and transports the sheet S.

Then, when the rear end of the sheet S passes through the nip portion between the transport roller 16 and the roller 17, as shown in FIG. 6, when the plunger 11 releases the force for attracting the core 11a, the clutch link spring is released. The pulling force of 19 causes the clutch link 18 to rotate in the counterclockwise direction in FIG. 6 about the rotating shaft 18d, and the toothless link 12 causes the rotating shaft 12 to rotate.
The core 11a is rotated clockwise about FIG.
Is pulled out in the direction of arrow c in FIG.

When the tooth-missing link 12 rotates in the clockwise direction in FIG. 6 about the rotary shaft 12c, the tooth-missing link claw 12a of the tooth-missing link 12 has a tooth-missing gear cam 7a provided on the pickup tooth-missing gear 7. When the clutch link 18 is disengaged from the toothless temporary stopper 7b of FIG. 6 and then at that time, the clutch link 18 is rotated counterclockwise in FIG. 6 about the rotation shaft 18d by the pulling force of the clutch link spring 19, 18c and the tooth-missing link connecting portion 12b are integrally pushed in the direction of arrow d in FIG. 6, and the clutch link tooth-missing claw 18b becomes the tooth-missing gear cam 7a.
Abuts the outer peripheral surface of.

Then, the pick-up tooth-chipped gear 7 tries to rotate counterclockwise in FIG. 6 around the shaft 13 by the pulling force of the tooth-chipped spring 10, but immediately contacts the outer peripheral surface of the tooth-chipped gear cam 7a. The sliding clutch link toothless pawl 18b is hooked on the toothless stopper 7c and locked, and the toothless portion of the pickup toothless gear 7 is held at a position facing the pickup idler gear 4 so that the pickup toothless gear 7 is The state where the pickup idler gear 4 is not meshed is maintained.

At the same time, the clutch link claw 18a of the clutch link 18 is hooked on the stopper 8b of the spring clutch mechanism 8 and locked, and the drive transmission to the output side of the spring clutch mechanism 8 is released, so that the spring clutch mechanism 8 is released. 8, the rotation of the conveying roller 16 connected to the output side of 8 stops, and
It returns to the initial standby state shown in. Then, the series of control operations described above are repeated to successively feed the subsequent sheets S.

With the above-described structure, in the present embodiment, the driving operation of the pickup roller 14 for feeding the sheet S by rotating about once and the sheet S fed by the pickup roller 14 for a predetermined plurality of rotations are further moved to the downstream side. Since the driving operation of the carrying roller 16 for carrying can be controlled by one plunger 11, the number of parts can be reduced and the cost can be reduced.

Further, in the above-described embodiment, the drive control of the two rotating bodies of the pickup roller 14 and the conveying roller 16 is performed by the single plunger 11, but it is equivalent to the pickup rollers which rotate in synchronization with each other. The present invention can also be applied to the case where there are a plurality of rotation control rotating bodies or a case where there are a plurality of rotating bodies corresponding to the transport rollers that rotate in synchronization with each other.

Next, the second embodiment of the sheet conveying device according to the present invention.
Embodiments will be described with reference to FIGS. 7 to 12. 7 is an explanatory plan view showing the configuration of the second embodiment of the sheet conveying device according to the present invention, FIG. 8 is an explanatory cross-sectional view showing the configuration of the second embodiment, and FIGS. 9 to 12 are operations of the second embodiment. It is a figure explaining.

As shown in FIGS. 7 and 8, a sheet feeding mechanism 51, which is a second embodiment of the sheet conveying apparatus according to the present invention, has various gear trains, which will be described in detail later, provided on the apparatus body frame. A pickup roller 64 having a half-moon-shaped cross section, which is a first sheet conveying unit for feeding out the sheet S accommodated in the sheet cassette B and serves as a first conveying rotating body, has a shaft 63 through a shaft 63. A pickup toothless gear 57 having a toothless portion is connected.

Further, downstream of the pick-up roller 64, there is disposed a second sheet conveying means, ie, a conveying roller 66 which serves as a second conveying rotator, and the conveying roller 66 is a shaft.
Spring clutch mechanism 58 serving as a spring clutch means via 65
Is connected to the output side.

A roller 67, which rotates following the rotation of the transport roller 66, is pressed against the transport roller 66 so that the sheet S fed by the pickup roller 64 is nipped by the transport roller 66 and the roller 67. Are transported.

The pickup tooth-missing gear 57 is provided with a tooth-missing gear cam 57a which is provided integrally with the pickup tooth-missing gear 57, and the tooth-missing gear cam 57a has a toothless gear serving as a first engaging portion. The tooth stopper 57b is arranged at a position substantially opposite to the tooth missing portion of the pickup tooth missing gear 57.

Further, a toothless link 62 is provided adjacent to the pick-up toothless gear 57 so as to be rotatable about a rotary shaft 62c with respect to the apparatus body frame, and one end of the toothless link 62 is provided at the apparatus body. It is fixed to the frame and is connected to the core 61a of the plunger 61 whose operation is appropriately controlled by the control means C shown in FIG.

Further, this one end is engaged with the other end of the toothless link spring 74 whose one end is engaged with the apparatus main body frame, whereby the toothless link 62 is pulled by the toothless link spring 74. Thus, it is constantly urged in the counterclockwise direction in FIG. 8 about the rotary shaft 62c.

A missing tooth link pawl 62a, which serves as a link lever, is provided at the other end of the missing tooth link 62, and the missing tooth link pawl 62a is actuated by the action of the plunger 61 to rotate the missing tooth link claw. 62a can be engaged with the toothless stopper 57b provided on the toothless gear cam 57a.

Further, an idler link 68 is provided adjacent to the pick-up tooth-missing gear 57 so as to be rotatable about a rotation shaft 68c with respect to the apparatus main body frame.
An idler link receiving portion 68a capable of contacting and engaging with the toothless link connecting portion 62b provided at one end of the toothless link 62 is provided at one end of the.

Further, at the other end of the idler link 68, there is provided an idler link pushing portion 68b capable of contacting and engaging with a clutch link connecting portion 69a provided at one end of a clutch link 69 which will be described later.

A rotary shaft 69d is provided adjacent to the idler link 68 and the spring clutch mechanism 58 with respect to the apparatus main body frame.
There is provided a clutch link 69 rotatable about the center of the clutch link 69. One end of the clutch link 69 is engaged with the other end of a clutch link spring 70 whose one end engages with the apparatus main body frame. Is constantly urged in the counterclockwise direction in FIG. 8 about the rotating shaft 69d by the pulling force of the clutch link spring 70.

Further, at the other end of the clutch link 69, as described above, an idler link interlocking with the toothless link 62 is provided.
A clutch link connecting portion 69a capable of abuttingly engaging the idler link pushing portion 68b of the 68 is provided.

A clutch link pawl 69b serving as a spring clutch control lever is provided at the other end of the clutch link 69. The clutch link claws are moved according to the rotating movement of the interlocking clutch link 69.
A stopper 69b serves as a second locking portion that releases the tightening force of the control spring 58c built into the spring clutch mechanism 58.
It is adapted to engage with 58b.

Further, an idler gear 71 is provided which is connected to the shaft 65 of the conveying roller 66, an idler gear 72 is meshed with the idler gear 71, and a timing pin 72a is erected at a predetermined position near the outer periphery of the idler gear 72. Has been done.

A timing cam 73 serving as a cam mechanism is provided adjacent to the idler gear 72 and the clutch link 69 so as to be rotatable with respect to the apparatus main body frame. The timing cam 73 is provided on the outer periphery thereof with the timing of the idler gear 72. A timing arm 73b corresponding to the pin 72a is arranged with a predetermined phase difference in the radial direction. In this embodiment, 6
A case where the six timing arms 73b are provided with a phase difference of 0 ° will be described.

At a predetermined position on the outer peripheral surface of the timing cam 73, there is formed a cam groove 73a into which the clutch link projection 69c provided at a predetermined position of the clutch link pawl 69b of the clutch link 69 can be dropped.

With the above structure, the idler gears 71 and 72 rotate in accordance with the rotation operation of the conveying roller 66, the timing pin 72a of the idler gear 72 engages with the timing arm 73b of the timing cam 73 to rotate the timing cam 73, and the clutch As shown in FIG. 9, the clutch link projection 69c provided on the clutch link claw 69b of the link 69 comes into contact with and slides on the outer peripheral surface of the timing cam 73, and as shown in FIG. It rotates around the moving shaft 69d in the counterclockwise direction in FIG. 9, the clutch link claw 69b is hooked on the stopper 58b and locked, and the conveying roller 66 is stopped.

A tooth-missing spring 60 having one end engaged with the apparatus main body frame is engaged with a predetermined position of the tooth-missing gear cam 57a fixed to the pickup tooth-missing gear 57. In the state where the tooth-missing portion faces the pickup idler gear 4, the pickup tooth-missing gear 57 is always centered around the shaft 63 by the pulling force of the tooth-missing spring 60.
Is biased in the counterclockwise direction.

In FIG. 8, when the rotational driving force is transmitted to the two-stage gear 52 from the drive transmission means connected to a drive source (not shown), the two-stage gear 53 and the idler gear 55 meshing with the two-stage gear 52 are rotationally driven. Then, the pickup idler gear 54 and the transport idler gear 56, which mesh with the two-stage gear 53 and the idler gear 55, are rotationally driven.

The pickup idler gear 54 is arranged at a position where it can mesh with a pickup tooth-missing gear 57 provided in a sheet pickup mechanism for rotationally driving a pickup roller 64 for feeding out the sheet S stored in the sheet cassette B. The pickup idler gear 54 and the pickup toothless gear 57 constitute clutch means for controlling the rotational drive of the pickup roller 64 which is the first sheet conveying means. The transport idler gear 56 meshes with a clutch gear 59 provided on the drive input side of a spring clutch mechanism 58 serving as clutch means.

The pickup roller 64, which is connected to the pickup tooth-missing gear 57 by the shaft 63, rotates integrally with the pickup tooth-missing gear 57 and feeds the sheet S accommodated in the sheet cassette B. In addition, the spring clutch mechanism 58 and the shaft
The conveyance roller 66, which is connected by the 65 and rotates integrally with the clutch control ring 58a, nip the sheet S fed by the pickup roller 64 in cooperation with a roller 67 arranged in pressure contact with the conveyance roller 66. And then transport.

As shown in FIG. 9, when the sheet feeding mechanism 51 is stopped and in the standby state, the core 61a of the plunger 61 is in the pulled-out position, and the tooth-missing link 62 has the tooth-missing link spring 74. The tooth-missing link claw 62a of the tooth-missing link 62 is biased counterclockwise in FIG. 9 by the pulling force about the rotary shaft 62c, and the tooth-missing gear cam 57a of the tooth-missing gear 57 has a tooth-missing gear. It is hooked on the stopper 57b and locked, and the pulling force of the tooth-missing spring 60 holds the tooth-missing portion of the pickup tooth-missing gear 57 in a position facing the pickup idler gear 54, whereby the pickup tooth-missing gear 57 is held. Is held in a state where it does not mesh with the pickup idler gear 54, and the pickup roller 64 is held in a stopped state.

At the same time, the cam groove of the timing cam 73
The position of 73a is such that the clutch link projection 69c is located in the cam groove 73a.
The phase is set so that the clutch link spring 70 pulls and the pivot shaft 69d is used as the center.
The clutch link claw 69b of the clutch link 69 biased in the counterclockwise direction is hooked on the stopper 58b provided on the outer periphery of the clutch control ring 58a of the spring clutch mechanism 58, and is locked in the spring clutch mechanism 58. Control spring 58c
Is loosened, the rotational driving force of the clutch gear 59 is interrupted in the spring clutch mechanism 58 and is not transmitted to the output side of the spring clutch mechanism 58, and the transport roller 66 connected to the output side of the spring clutch mechanism 58 is in a stopped state. Retained.

Next, as shown in FIG. 10, when a command for feeding the sheet S is sent from the main body of the image forming apparatus A and the sheet feeding mechanism 51 is in the feeding state for feeding the sheet S. , The core 61a of the plunger 61 is pulled in the direction of arrow e in FIG. 10 against the pulling force of the toothless link spring 74, and the toothless link 62 connected to the core 61a is centered around the rotation shaft 62c in FIG. The tooth-missing link claw 62a is disengaged from the tooth-missing stopper 57b of the tooth-missing gear cam 57a provided on the pickup tooth-missing gear 57, and the pickup tooth-missing gear 57 becomes a tooth-missing spring.
The pulling force of 60 rotates the shaft 63 in the counterclockwise direction around the shaft 63, and the teeth of the pickup toothless gear 57 meshes with the pickup idler gear 54. The pickup tooth-chipped gear 57 is transmitted by being transmitted to the tooth gear 57, and the pickup roller 64 connected to the pickup tooth-chipped gear 57 via the shaft 63 is rotated to feed the sheet S accommodated in the sheet cassette B.

At the same time, the toothless link connecting portion 62b of the toothless link 62 is an idler link receiving portion of the idler link 68.
Push 68a in the direction of arrow f in Fig. 10 to move the idler link.
When the 68 rotates in the counterclockwise direction in FIG. 10 about the rotation shaft 68c, the idler link pushing portion 68b causes the clutch link connecting portion 69a of the clutch link 69 to move in the direction of arrow g in FIG.
Push in the direction.

As a result, the clutch link 69 rotates in the clockwise direction in FIG. 10 about the rotation shaft 69d against the pulling force of the clutch link spring 70, and the clutch link pawl 69
b is disengaged from the stopper 58b of the spring clutch mechanism 58, the control spring 58c in the spring clutch mechanism 58 is tightened, the rotational driving force of the clutch gear 59 is transmitted to the output side of the spring clutch mechanism 58, and the output side of the spring clutch mechanism 58. The conveying roller 66 rotates via a shaft 65 connected to the sheet, and the sheet S fed by the pickup roller 64 is nipped and conveyed by the conveying roller 66 and the roller 67.

Next, before the pickup partly tooth-missing gear 57 makes one rotation, as shown in FIG. 11, the plunger 61 is moved to the core 61a.
11 is released by the pulling force of the toothless link spring 74 in the direction of arrow h in FIG. 11, the toothless link 62 connected to the core 61a is rotated by the tensile force of the toothless link spring 74. Rotating in the counterclockwise direction in FIG. 11 about the drive shaft 62c, the toothless link pawl 62a contacts the outer peripheral surface of the toothless gear cam 57a.

With the rotation of the pickup tooth-missing gear 57, the tooth-chipped link claw 62a abuts and slides along the outer peripheral surface of the tooth-chipped gear cam 57a, and when the pickup tooth-chipped gear 57 makes one full rotation, The link claw 62a is hooked on the toothless stopper 57b and locked, and the pickup roller 64 stops rotating.

When the plunger 61 releases the force of attracting the core 61a, the toothless link 62 rotates counterclockwise in FIG. 11 about the rotation shaft 62c, and the toothless link 62 is rotated. When the idler link 68 interlocked with is rotated about the rotation shaft 68c in the clockwise direction in FIG. 11, the idler link pushing portion 68b of the idler link 68 and the clutch link connecting portion 69a of the clutch link 69 contact each other. The contact engagement is released and the clutch link 69 is rotated counterclockwise in FIG. 11 about the rotation shaft 69d by the pulling force of the clutch link spring 70, and the clutch link projection 69c of the clutch link pawl 69b is timed. It contacts the outer peripheral surface of the cam 73.

At this time, the clutch link projection 69c is formed in the cam groove.
The clutch link 69 is held as it is because it cannot fall into the 73a, and the clutch link pawl 69b is also held in a state of being disengaged from the stopper 58b of the spring clutch mechanism 58.

As a result, the idler gear 71 connected to the shaft 65 of the conveying roller 66 and the idler gear 72 meshing with the idler gear 71 continue to rotate, and the timing pin 72a provided on the idler gear 72 is attached to the timing arm 73b of the timing cam 73. When engaged, the timing arm 73b is pushed to rotate the timing cam 73 counterclockwise in FIG. 11 about the rotary shaft 73c, and the timing cam 73 is rotated by 60 ° each time the idler gear 72 makes one rotation. At this time,
The clutch link projection 69c of the clutch link pawl 69b comes into contact with the outer peripheral surface of the timing cam 73 and slides.

After the trailing edge of the sheet S passes through the nip portion between the conveying roller 66 and the roller 67, the timing cam is further moved.
When the 73 rotates around the rotation shaft 73c in the counterclockwise direction in FIG. 11 and the clutch link protrusion 69c reaches the position corresponding to the cam groove 73a of the timing cam 73 as shown in FIG. The pulling force of the spring 70 causes the clutch link 69 to rotate counterclockwise in FIG. 12 about the rotation shaft 69d, the clutch link projection 69c to fall into the cam groove 73a, and the clutch link pawl 69b to move the spring clutch mechanism 58.
The spring clutch mechanism
The drive transmission of 58 is released and the rotation of the conveyance roller 66 is stopped.

At this time, the clutch link connecting portion 69a of the clutch link 69 abuts and engages with the idler link pushing portion 68b of the idler link 68 to return to the initial standby state shown in FIG. Then, the series of control operations described above are repeated to successively feed the subsequent sheets S.

With the above-described structure, in the present embodiment, the driving operation of the pickup roller 64 for feeding the sheet S by one rotation and the sheet S fed by the pickup roller 64 for a plurality of predetermined rotations are further moved to the downstream side. Since the driving operation of the carrying roller 66 for carrying can be controlled by one plunger 61, the number of parts can be reduced and the cost can be reduced.

Further, in the above-described embodiment, the drive control of the two rotating bodies of the pickup roller 64 and the conveying roller 66 is performed by the single plunger 61, but it is equivalent to the pickup rollers which rotate in synchronization with each other. The present invention can also be applied to the case where there are a plurality of rotation control rotating bodies or a case where there are a plurality of rotating bodies corresponding to the transport rollers that rotate in synchronization with each other.

Next, an example of an image forming apparatus equipped with the sheet conveying apparatus of each of the above embodiments will be described with reference to FIG.
FIG. 13 is a cross-sectional explanatory view showing the overall configuration of an image forming apparatus equipped with the sheet conveying device according to the present invention. In addition, the first,
Components configured in the same manner as in the second embodiment are given the same reference numerals and description thereof is omitted.

In each of the above-mentioned embodiments, the second sheet conveying means is constituted by the conveying roller pair constituted by the conveying rollers 16 (66) and the rollers 17 (67), but in the present embodiment, the second sheet is formed. A case will be described in which the conveying means is composed of a pair of separating rollers which is a sheet separating means composed of the feed roller 16 (66) and the retard roller 17 (67).

In this embodiment, the feed roller 16 (66) and the retard roller 17 which act as the sheet separating means.
(67) rotationally drives the feed roller 16 (66) in the sheet feeding direction and rotationally drives the retard roller 17 (67) in the opposite direction to the sheet feeding direction, so that the pickup roller 14 is picked up from the sheet cassette B. Only the uppermost one of the sheets S fed out by (64) can be separated and fed.

The image forming apparatus (laser beam printer) A equipped with the sheet conveying apparatus of each of the above embodiments is shown in FIG.
As shown in, the sheet S stored in the sheet cassette B
Is fed out by the pickup roller 14 (64) driven and controlled by the sheet feeding mechanism 1 (51) of the first and second embodiments, and is fed to the feed roller 16 (66) and the retard roller.
Separated one by one by a pair of separation rollers consisting of 17 (67),
The electrophotographic photosensitive drum 83 disposed in the process cartridge 82, which serves as an image forming unit, is conveyed to the image forming unit which is opposed by the conveying rollers 80 and 81 arranged further downstream.

On the other hand, a laser beam based on image information is irradiated from the optical system 84 onto the surface of the uniformly charged photosensitive drum 83 to form a latent image, and the latent image is formed on the process cartridge 82. A toner image is formed by a developing device provided inside.

Then, the sheet S is conveyed to the nip portion between the photoconductor drum 83 and the transfer roller 85 in synchronization with the rotation of the photoconductor drum 83, and a voltage is applied to the transfer roller 85, whereby the surface of the photoconductor drum 83 is transferred. The toner image formed on the sheet S is transferred to the sheet S.

Then, the sheet S after the image transfer is conveyed to a fixing roller pair 86 having a built-in heater to fix the toner image on the sheet S, and the sheet S on which the image is fixed is discharged to the discharging roller pair.
It is configured to be conveyed by 87 and 88 and discharged to a discharge tray 89 provided outside the machine.

In the above embodiment, the first sheet conveying means is constituted by the pickup roller 14 (64) for feeding the sheet S from the sheet cassette B, and the second sheet conveying means is constituted by the conveying roller 16 (66) and the roller. 17 (67) with conveying roller pair or feed roller 16 (66) and retard roller
Although an example in which the separation roller pair composed of 17 (67) is used is shown, the first sheet conveying means may be composed of a sheet separating means as another structure.

Further, in each of the above-mentioned embodiments, the pickup idler gears 4, 54 and the pickup tooth-missing gears 7, 57 are used as clutch means for controlling the rotational driving of the pickup rollers 14, 64 which are the first sheet conveying means. However, the spring clutch may be used as another structure.

In the above-mentioned embodiment, the laser beam printer is exemplified as the image forming apparatus, but the invention is not limited to this, and it can be applied to other image forming apparatuses such as a copying machine and a facsimile machine. Can also be applied to an image forming apparatus equipped with an image forming unit having an inkjet head or a thermal head.

[0099]

Since the present invention has the above-described structure and operation, it is possible to use a single plunger that requires a plurality of plungers to drive and control a plurality of sheet conveying means in the conventional example. By enabling the drive control, it is possible to reduce the number of parts and reduce the cost.

[Brief description of the drawings]

FIG. 1 is an explanatory plan view showing a configuration of a first embodiment of a sheet conveying device according to the present invention.

FIG. 2 is a cross-sectional explanatory view showing the configuration of the first embodiment.

FIG. 3 is a diagram illustrating an operation of the first embodiment.

FIG. 4 is a diagram illustrating the operation of the first embodiment.

FIG. 5 is a diagram illustrating the operation of the first embodiment.

FIG. 6 is a diagram illustrating the operation of the first embodiment.

FIG. 7 is an explanatory plan view showing the configuration of the second embodiment of the sheet conveying device according to the present invention.

FIG. 8 is an explanatory cross-sectional view showing the configuration of the second embodiment.

FIG. 9 is a diagram illustrating the operation of the second embodiment.

FIG. 10 is a diagram illustrating an operation of the second embodiment.

FIG. 11 is a diagram illustrating the operation of the second embodiment.

FIG. 12 is a diagram illustrating an operation of the second embodiment.

FIG. 13 is a cross-sectional explanatory diagram showing an overall configuration of an image forming apparatus including a sheet conveying device according to the present invention.

FIG. 14 is a diagram illustrating a conventional example.

FIG. 15 is a diagram illustrating a conventional example.

[Explanation of symbols]

1 ... Sheet feeding mechanism, 2, 3 ... Two-stage gear, 4 ... Pickup idler gear, 5 ... Idler gear, 6 ... Conveyor idler gear, 7 ... Pickup missing gear, 7a ... Missing gear cam, 7b ... Missing tooth temporary stopper, 7c ... missing tooth stopper, 8 ...
Spring clutch mechanism, 8a ... Clutch control ring, 8b ... Stopper, 8c ... Control spring, 9 ... Clutch gear, 10 ... Missing spring, 11 ... Plunger, 11a ... Core, 12 ... Missing link,
12a ... missing tooth link claw, 12b ... missing tooth link connecting part, 12c ...
Rotating shaft, 13 ... Shaft, 14 ... Pickup roller, 15 ... Shaft, 16
... conveying roller (feed roller), 17 ... roller (retard roller), 18 ... clutch link, 18a ... clutch link claw, 18b ... clutch link missing tooth claw, 18c ... clutch link connecting part, 18d ... rotating shaft, 19 … Clutch link spring,
51 ... Sheet feeding mechanism, 52, 53 ... Two-stage gear, 54 ... Pickup idler gear, 55 ... Idler gear, 56 ... Conveyor idler gear, 57 ... Pickup missing gear, 57a ... Missing gear cam, 57b ... Missing stopper, 58 ... Spring clutch mechanism, 58a
... clutch control ring, 58b ... stopper, 58c ... control spring,
59 ... Clutch gear, 60 ... Missing teeth spring, 61 ... Plunger,
61a ... core, 62 ... missing tooth link, 62a ... missing tooth link claw, 62
b ... missing tooth link connecting part, 62c ... rotary shaft, 63 ... shaft, 64 ... pickup roller, 65 ... shaft, 66 ... transport roller (feed roller), 67 ... roller (retard roller), 68 ... idler link, 68a ... Idler link receiving part, 68b ... Idler link pushing part, 68c ... Rotating shaft, 69 ... Clutch link, 69
a ... Clutch link connecting part, 69b ... Clutch link claw,
69c ... Clutch link protrusion, 69d ... Rotating shaft, 70 ... Clutch link spring, 71, 72 ... Idler gear, 72a ... Timing pin, 73 ... Timing cam, 73a ... Cam groove, 73b ... Timing arm, 73c ... Rotating shaft, 74 ... missing tooth link spring,
80, 81 ... Conveying rollers, 82 ... Process cartridges, 83 ...
Photoconductor drum, 84 ... Optical system, 85 ... Transfer roller, 86 ... Fixing roller pair, 87, 88 ... Ejection roller pair, 89 ... Ejection tray, A
... image forming apparatus, B ... sheet cassette, C ... control means,
S ... sheet

Claims (8)

[Claims] 1. A sheet conveying device, wherein each of the sheet conveying operations by a plurality of sheet conveying means for conveying a sheet is configured to be controlled by a single plunger. 2. A first sheet conveying means for conveying a sheet, and a second sheet conveying means arranged downstream of the first sheet conveying means in the sheet conveying direction for conveying a sheet. A clutch means for transmitting / not transmitting a driving force is provided to each of the first and second sheet conveying means, and the clutch means is controlled to perform the sheet conveying operation of the first and second sheet conveying means. A sheet conveying device, which is provided with one plunger for controlling. 3. The clutch means provided in the first sheet conveying means comprises an idler gear that transmits a driving force and a toothless gear that can engage / disengage with the idler gear. The driving force is transmitted / not transmitted by restricting / releasing, and the clutch means provided in the second sheet conveying means is a spring clutch, and restricts / releasing the clutch control ring by the plunger. The sheet conveying apparatus according to claim 2, wherein the driving force is transmitted / not transmitted by performing the operation. 4. A first sheet conveying means for conveying a sheet, and a second sheet conveying means arranged downstream of the first sheet conveying means in the sheet conveying direction for conveying a sheet. In the sheet conveying device, an idler gear to which a driving force from a drive source is transmitted, a toothless gear that can be engaged / disengaged with the idler gear, the first sheet conveying means connected to the toothless gear, A first locking portion integrally provided with the toothless gear, a second locking portion integrally provided with the toothless gear, and engaging with the first locking portion A first link lever that suppresses rotation of the partly toothed gear, a second link lever that engages with the second locking portion and restricts rotation of the partly toothed gear, and the first and second The driving force from the drive source and the plunger that drives the link lever of The spring clutch mechanism that is reached, the second sheet conveying unit that is provided on the output side of the spring clutch mechanism, the first and second link levers, and the spring clutch mechanism. A sheet conveying device, comprising: a spring clutch control lever that engages with a third locking portion to suppress rotation of the spring clutch mechanism. 5. A first sheet conveying means for conveying a sheet, and a second sheet conveying means arranged downstream of the first sheet conveying means in a sheet conveying direction for conveying a sheet. In the sheet conveying device, an idler gear to which a driving force from a drive source is transmitted, a toothless gear that can be engaged / disengaged with the idler gear, the first sheet conveying means connected to the toothless gear, A first locking portion integrally provided with the tooth-chipped gear, a link lever that engages with the first locking portion to suppress rotation of the tooth-chipped gear, and drives the link lever A plunger, a spring clutch mechanism to which a driving force from a driving source is transmitted, the second sheet conveying means provided on an output side of the spring clutch mechanism, the link lever, and the spring clutch mechanism. Spring clutch control lever that engages with a second locking portion provided in the switch mechanism to suppress rotation of the spring clutch mechanism, and operates in conjunction with rotation of the spring clutch mechanism to perform the spring clutch control. And a cam mechanism that controls an engagement operation between a lever and the second locking portion. 6. The first sheet conveying means is a pickup roller for feeding out the sheet accommodated in the sheet accommodating means, and the second sheet conveying means separates the sheet delivered by the pickup roller. The sheet conveying device according to any one of claims 1 to 5, wherein the sheet conveying device is a pair of separating rollers including a feed roller and a retard roller. 7. The first sheet conveying means is configured to include a first conveying rotating body, the second sheet conveying means is configured to include a second conveying rotating body, and the plunger is provided. 6. The second transport rotator is configured to rotate a predetermined number of times while the first transport rotator makes one rotation by the control of FIG. The sheet conveying device described. 8. A sheet carrying device according to claim 1, further comprising an image forming means for forming an image on a sheet carried by the sheet carrying device according to image information. A characteristic image forming apparatus.