JPH0712353Y2 - Sheet transport device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a sheet conveying device for feeding a sheet to a platen of an image processing apparatus such as a copying machine or an image reader, or an image forming unit.

[Conventional technology]

Generally, a sheet conveying device of this type, for example, an automatic document feeder mounted on a platen of a copying machine, feeds out a sheet set in a paper feed stacker by a pickup roller, and separates the sheet by a separating means. After separating, the leading edge of the sheet is abutted against the stopped registration roller, and in this state, the trailing edge of the sheet is further fed to correct the registration by bending the sheet, and then to the reference position on the platen of the copying machine by the conveyor belt. Transporting. Then, when copying is completed, the conveyance belt is driven to carry the sheet out of the platen, and the sheet is ejected to the sheet ejection stacker by the sheet ejection roller.

However, conventionally, in this type of apparatus, a paper feed system from the pickup roller to the registration roller and a paper ejection system from the registration roller to the paper ejection roller are respectively provided with one motor using a one-way clutch. It is known to control the rotation in one direction by each of forward and reverse rotation.

Further, there is also known one in which the registration roller is provided with an aligning means for correcting the posture of the sheet, and further, one in which the pickup roller is moved up and down and brought into contact with and separated from the sheet by forward and reverse rotation of one motor for each sheet feeding. .

[Problems to be Solved by the Invention] However, in a device that tentatively gathers these conventionally known technologies, forward / reverse rotation of a motor is used, for example, the sheet is fed to the registration roller in forward rotation, and bending is applied here. Even if the posture is corrected, when the motor is switched to reverse rotation and the paper ejection system is driven next, the leading edge of the aligned sheet is fed downstream due to the rotation of the registration rollers, and at the same time the pickup roller is rotated and reversely rotated. Then, while the pickup is completely released from the sheet surface from the state of being pressed downward, the above-mentioned sheet that is bent and fed out to correct the posture is pulled in the opposite direction, and becomes a load of sheet conveyance of the registration roller. Not only that, but this pulling in may disturb the posture of the seat aligned by the bent posture correction.

Further, when the pickup roller is raised and lowered on the sheet and brought into contact with and separated from the sheet, the pickup roller starts rotating simultaneously with the raising and lowering, and particularly when the pickup roller descends and comes into contact with the sheet, the rotation of the pickup roller causes the sheet to move. There was a risk of disturbing the delivery posture.

[Purpose of device]

This invention drives and controls both the paper feed system and the paper discharge system by the forward and reverse operation of one motor to feed sheets one by one, and when feeding from the stacker and from the paper feed system. An object of the present invention is to obtain a sheet conveying apparatus which can always maintain the correct posture of the sheet when delivering the sheet to the conveying system and can achieve these operations with an extremely simple structure.

[Outline of device]

In order to achieve the above-mentioned object, the present invention provides (1) a feeding means that is supported by a sheet accommodated in a sheet feeding stacker so as to be able to come into contact with and separate from the sheet, and separates the sheet fed by the feeding means one by one. And a conveying means for conveying the sheet separated and fed by the separating means, and
A sheet conveying device having a motor capable of rotating in the normal and reverse directions, wherein the feeding means and the separating means are driven by the normal rotation of the motor, and the conveying means is driven by the reverse rotation of the motor. (2) Forward and reverse directions of the motor When the motor is rotated in reverse and a load larger than a predetermined value is applied when the motor rotates in reverse,
Torque limiter, a second torque limiter that receives a rotational force from the first torque limiter, and idles when a load greater than a predetermined value is applied during forward rotation of the motor, and the second torque limiter.
Has a base end supported by the torque limiter, and a support member that rotatably supports the feeding means at a tip end that swings around the base end, and when the motor rotates forward, The load due to the contact of the supporting member with the restriction member provided at the predetermined position in the reverse direction of the supporting member when the motor rotates in the reverse direction while the feeding unit is kept in contact with the seat by the idling of the second torque limiter due to the pressing load. The first torque limiter idles to provide an elevating mechanism that keeps the feeding means in a non-contact state with the seat. (3) The base end of the support member and the rotation shaft of the feeding means are rotated. A sheet conveying device, which is drivingly connected to the center and includes a transmission unit that receives the rotational force from the first torque limiter and transmits the rotational force to the feeding unit when the motor rotates in the normal direction. Is.

[Operation] The automatic sheet feeding device according to the present invention having the above-described configurations (1) to (3) operates as follows.

With the configuration of (1), the leading end portion of the sheet separated in the sheet feeding direction by the single motor in the forward rotation is regulated by the aligning means in the stopped state by the forward rotation of the motor to loosen and align the sheet. After that, by rotating the motor in the reverse direction to cut off the rotational force of the motor to the feeding means and the separating means and hold it in a stopped state, slack is given to the sheet and the aligned sheet is not fed back.
By the aligning means, it is possible to feed the conveying means while keeping the aligned state of the sheets.

With the configuration of (2), after the sheets are aligned by the forward rotation of the motor, the contact state of the sheet with the feeding means is released in synchronization with the timing of conveying the sheets in the reverse rotation.
The aligned state can be maintained without pulling the sheets aligned and conveyed by the aligning means. At the same time, the drive system of the feeding means and the motor are disconnected by the idling of the first torque limiter, and the load on the motor is reduced.

According to the configuration of (3), when the feeding means is moved to the position where the second torque limiter is in contact with the idle seat due to the normal rotation of the motor, and when the first torque limiter is idle due to the reverse rotation of the motor, it is not in contact with the seat. When moving to the position, the rotation of the support member that supports the feeding means and the rotation cycle of the transmitting means coincide with each other, so that the feeding means receives no rotational force from the first torque limiter and the feeding means does not move. Does not rotate. For this reason, particularly, the forward rotation of the motor does not rotate until the feeding means comes into contact with the sheet and idles, so that the sheet can be fed without displacement when the feeding means comes into contact with the sheet.

With the configuration of (4), the operations of (1) to (3) can be automatically repeated until the sheets on the paper feed stacker are exhausted.

[Example of device]

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

<Structure> As shown in FIG. 1, an image processing apparatus, for example, a platen 2 (original setting section) of a copying machine 1 is provided with a sheet conveying apparatus, for example, an automatic original feeding apparatus 3, which can be opened and closed.

The automatic document feeder 3 separates the originals set on the paper feed stacker (original tray) 4 into which the originals are set with the first page facing down, and separates the originals set on the paper feed stacker 4 into one sheet. Separating section 5 for sending out to and a conveying section 6 for conveying the document sent out from the separating section 5 along the platen 2.
A sheet discharging section 7 for reversing and ejecting the document conveyed on the platen 2 by the conveying section 6; and a sheet discharge stacker 8 (sheet discharging tray) for storing the document discharged from the sheet discharging section 7. ), A control device (not shown), and the drive device of FIG.

The paper feed stacker 4 is provided with side edge guides which are movable in opposite directions by the same amount so that the originals are always held at the center in the width direction.

Paper feed guides 9 and 10 that form a paper feed path in the separation unit 5, feeding means for feeding the document set in the paper feed stacker 4, such as a pickup roller 11, and whether the document is set in the paper feed stacker 4 or not. Empty sensor 12 for detecting whether or not, a paper feed roller 13 that rotates in the paper feed direction, a separation roller 14 that rotates in a direction in which the original that follows the original fed by the paper feed roller 13 is retracted, and the width of the original A size detection sensor 15 for detecting the size in the direction, a registration sensor 16, and a conveyance unit such as registration rollers 17 and 18 are provided.

The paper feed roller 13 is attached to the rotary shaft 40 shown in FIG. 2 via a one-way clutch. Further, the paper feed roller 13 and the separation roller 14 constitute a separation means.

Further, the pickup roller 11 has its rotating shaft 42 supported by a pair of arms 44 (supporting members) whose base ends are attached to the rotating shaft 40 via a spring clutch 43 (second torque limiter). Then, the rotary shaft 40 through the gears 58, 59, 60.
Is transmitted to the rotary shaft 42.

The spring clutch 43 is designed to idle when a load larger than a predetermined value is applied during normal rotation of the motor 30, which will be described later.

The transport unit 6 includes a pair of rollers 19 and 20 and the rollers 19 and 20.
A conveyor belt 21 (conveying means) stretched between the plurality of press rollers that presses the conveyor belt 21 against the platen 2 side.
22 and.

As shown in FIG. 2, a pulley 46 is attached to the rotary shaft 45 of the roller 19, and a pulley 48 is attached to the rotary shaft 47 of the roller 20.

The paper discharge unit 7 includes paper discharge guides 23 and 24 that form a paper discharge path.
Synthetic resin sheet 25 attached to the lower end of the paper ejection guide 24
A pinch roller 26 attached to the paper ejection guide 24 and pressed against the conveyor belt 21, a paper ejection sensor 27, and a paper ejection roller 28.
And a leaf spring 29 pressed against the paper discharge roller 28.

As shown in FIG. 2, a pulley is attached to the rotation shaft 49 of the discharge roller 28.
50 is installed, this pulley 50 is a pulley 48 and a round belt
51 connected.

The control device includes, for example, a microcomputer and a sensor
The motor 30, which will be described later, is driven and controlled by the signals 12, 15, 16, 27 and the signal from the copying machine 1.

As shown in FIG. 2, the driving device is a motor 30 that can rotate forward and backward, a pulley 32 attached to a rotating shaft 31 of the motor 30, a pulley 34 attached to the rotating shaft 33, a pulley 32 and a pulley.
Timing belt 35 connecting with 34 and spring clutch 37
A gear 38 attached to the rotary shaft 33 via a (first torque limiter), a gear 39 meshing with the gear 38, a gear 41 attached to the rotary shaft 40 of the paper feed roller 13 and meshing with the gear 39, A gear 52 that meshes with the gear 41, a gear 54 that is attached to the rotating shaft 53 of the separation roller 14 and meshes with the gear 52,
Rotation shaft via one-way clutch (third clutch)
The gear 36 attached to the 33, the gear 56 attached to the rotating shaft 55 of the registration roller 17, and meshing with the gear 36,
It has a gear 57 that meshes with 46 and 56.

The spring clutch 37 is designed to idle when a load larger than a predetermined value is applied when the motor 30 rotates in the reverse direction.

Further, a member that transmits the rotational force of the motor 30 to the pickup roller 11, the paper feed roller 13, and the separation roller 14 by the normal rotation of the motor 30 is the first transmission means, and the reverse rotation of the motor 30 causes the registration roller 17, Motor 30 for the conveyor belt 21 and the paper discharge roller 28
The member for transmitting the rotational force of is the second transmission means.

<Operation> With the above-mentioned configuration, the automatic document feeder operates as follows.

First, when the original is set on the paper feed stacker 4 with the front side facing down, the empty sensor 12 detects the original and the original can be automatically fed.

In such a state, when a paper feed button (not shown) of the copying machine 1 or the automatic document feeder 3 is pressed, a start signal is issued in step S1 as shown in FIG. 3 to start the paper feed operation.

Then, in step S2, the state of the empty sensor 12 is determined, and if it is ON, the motor 30 rotates normally (in the direction of the solid line arrow) in step S3.

As a result, the pulley 32, the timing belt 35, and the pulley 3
4. The rotating shafts 40, 53 rotate in the forward direction via the gears 38, 39, 41, 52, 54.

The arm 44 is lowered by the forward rotation of the rotary shaft 40, and the pickup roller 11 comes into contact with the document. Therefore, the spring clutch 43
The load is applied to and slips, and the pickup roller 11 keeps in contact with the document.

Further, the paper feed roller 13 and the pickup roller 11 are normally rotated by the normal rotation of the rotary shaft 40, and the document is sent out.

On the other hand, the rotation of the rotating shaft 53 causes the separation roller 14 to rotate in a direction in which the document is not fed, and the document that follows the document fed by the sheet feeding roller 13 is rejected to separate the document into one sheet.

By the way, since the one-way clutch is interposed in the gear 36, the gear 36 does not rotate when the motor 30 rotates in the normal direction.

When the document reaches the size detection sensor 15, it is turned on if the document is long in the width direction and remains off if it is long in the length direction.

In step S4, the state of the registration sensor 16 is judged, and if a document is detected, the motor 30 is stopped after a certain time in step S5.

At this time, since the registration rollers 17 and 18 are stopped, the document is bent and the front end of the document is registered and corrected.

By stopping the motor 30, the pickup roller 11, the paper feed roller 13, and the separation roller 14 also stop.

When the motor 30 rotates in the reverse direction (in the direction of the broken arrow) in step S6, the rotating shaft 40 also rotates in the reverse direction, the arm 44 moves up, and the pickup roller 11 separates from the document. When the arm 44 hits a stopper (not shown), the spring clutch 37 is loaded and the gear 38 stops rotating. Therefore, when the pickup roller 11 is raised, the pickup roller 11,
The paper feed roller 13 and the separation roller 14 are stopped.

On the other hand, due to the reverse rotation of the motor 30, the rotational force of the rotary shaft 33 is
Are transmitted to the gears 56, 57, 46, the conveyor belt 21, and the round belt.
The registration roller 17, the conveyor belt 21, and the paper discharge roller 28 rotate via 51.

When the trailing edge of the document passes the registration sensor 16, the size of the document is detected in step S8 by the amount of rotation of the motor after the registration sensor 16 is turned on and the size detection sensor 15 being turned on and off. As a result, the size of the copy sheet is selected or the copy magnification is set according to the detected size.

When the registration sensor 16 detects the trailing edge of the document, counting for determining the document stop position is started.

In step S9, just before the leading edge of the document reaches the stop position,
The motor 30 is spun down to provide document stopping.

When the predetermined count, which would have caused the document to reach the stop position on the platen 2, ends, the motor 30 stops in step S10.

Then, in step S11, the copying operation of the copying machine 1 is performed,
Copied on paper.

When the copying is completed, the motor 30 reverses the rotation again in step S12, and the original on the platen 2 is sent to the paper output unit 7.

In step S13, after the discharge sensor 27 detects the leading edge of the document, the motor 30 is decelerated after a predetermined count, and the document is slowly discharged to the discharge stacker 8.

In step S14, the motor 30 is stopped after a predetermined time has elapsed since the paper discharge sensor 27 detected the trailing edge of the document, and the feeding / feeding of one document is performed.
The paper discharge operation ends in step S15.

In the case of continuous paper feeding, the process returns to step S2, the next original is sent out, and the same operation is performed.

[Effect of device]

According to this invention, utilizing the forward and reverse rotation of a single motor,
The leading end portion of the sheet in the sheet feeding direction separated by the separating means by the normal rotation of the motor is regulated by the aligning means in the stopped state by the normal rotation of the motor to loosen and align the sheet, and then the feeding means by the reverse rotation of the motor. By stopping the rotational force of the motor to the separating means and holding it in the stopped state, the slack is given to the sheet and the sheet in the aligned state is not fed backward, but the aligning means keeps the aligned state of the sheet and feeds out the conveying means. Can
Also, after the sheets are aligned by the forward rotation of the motor, the sheet contacted by the feeding means is released in synchronization with the timing of conveying the sheets in the reverse rotation, so that the sheets aligned and conveyed by the alignment means can be pulled. Without
The alignment can be maintained. At the same time, the drive system of the feeding means and the motor are disconnected by the idling of the first torque limiter, the load on the motor can be reduced, and the second torque limiter idles by the forward rotation of the feeding means. When moving to a position where the first torque limiter idles due to the reverse rotation of the motor and when moving to a non-contact position, the rotation of the support member that supports the feeding means and the rotation cycle of the transmission means match. Therefore, the feeding means does not receive the rotational force from the first torque limiter, and the feeding means does not rotate. For this reason, particularly when the feeding means does not rotate until the feeding means comes into contact with the sheet and rotates idly, the sheet can be fed without displacement when the feeding means comes into contact with the sheet. It is possible to control forward / reverse rotation to feed, align, convey, and discharge sheets, and simultaneously move up and down the feeding means and the drive system of the feeding means, and the sheet position when the feeding means contacts the sheet. It is possible to obtain a sheet conveying device that can be fed without misalignment, in particular, the sheet aligned by the aligning means is not pulled backward, and the load can be reduced to reliably transport the sheet.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 3 are views showing an embodiment of the present invention, FIG. 1 is a sectional view of a schematic structure of an automatic sheet feeding device, and FIG. 2 is a structure of a driving device. FIG. 3 is a flowchart for explaining the operation. DESCRIPTION OF SYMBOLS 1 ... Copier (image processing device), 2 ... Platen, 3 ... Automatic sheet feeding device, 4 ... Paper feed stacker, 5 ... Separation part (separation means), 11 ... Pickup roller (feeding means), 13
… Paper feed rollers, 17, 18… Registration rollers (alignment means), 2
1 ... Conveyor belt, 28 ... Paper discharging roller (paper discharging means), 30 ... Motor, 37 ... Spring clutch (first torque limiter), 43
... Spring clutch (second torque limiter), 58-60 ... Gear (third transmission means)

Claims (1)

[Scope of utility model registration request] 1. A feeding means which is supported by a sheet accommodated in a sheet feeding stacker so as to be able to come into contact with and separate from the sheet and which feeds out the sheet.
The sheet feeding device includes a separating unit that separates and feeds the sheets fed by the feeding unit and a conveying unit that conveys the sheets separated and fed by the separating unit, and has a motor that can rotate forward and backward. Then, in the sheet conveying apparatus in which the forward rotation of the motor drives the feeding means and the separating means, and the reverse rotation of the motor drives the conveying means, the reverse rotation of the motor receives the rotational force in the forward and reverse directions of the motor. At times, a first torque limiter that idles when a load of a predetermined amount or more acts, and a second torque limiter that receives a rotational force from the first torque limiter and idles when a load of a predetermined amount or more acts when the motor rotates in the normal direction. And a support member having a base end portion supported by the second torque limiter, and a support member rotatably supporting the feeding means at a tip end portion swinging around the base end portion, When the motor rotates in the forward direction, the second torque limiter idles due to a pressing load on the seat surface to keep the feeding means in contact with the seat, and when the motor rotates in the reverse direction, the support member moves to a predetermined position in the reverse direction of the support member. An elevating mechanism is provided for keeping the feeding means in a non-contact state with the seat by the first torque limiter idling under a load caused by abutting against the regulation member provided, and the base end portion of the support member and the Drive means connected to each other with the rotation shafts of the feeding means as rotation centers, receiving transmission force from the first torque limiter, and transmitting means for transmitting the rotation force to the delivery means during forward rotation of the motor. Sheet transport device.