JPH11124245A - Sheet feeding device and image processing device - Google Patents

Abstract

An object of the present invention is to prevent the leading edge of a sheet material from being pushed in with a low-cost and simple configuration and to avoid pushing out the sheet material at the moment when a document comes off from a feeding roller or the like. Accordingly, it is an object of the present invention to provide a sheet feeding apparatus and an image processing apparatus which can prevent image disturbance. A representative configuration of a sheet material feeding device and an image processing unit according to the present invention for solving the above problems is as follows.
A sheet material mounting table on which a plurality of sheet materials can be stacked, sheet material regulating means for regulating the leading end of the sheet material placed on the sheet material mounting table, and a sheet material fed separately Sheet material feeding means for feeding the sheet material, and moving the sheet material regulating means to a position where the regulation of the leading end of the sheet material is released with the forward rotation of the sheet material feeding means in the sheet material conveying direction; Along with the rotation, the sheet material is moved to a position where the leading end is regulated, and the sheet material feeding means is provided with a load means that applies a load to rotation when rotating forward and does not apply a load when rotating reversely. It is characterized by comprising.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material feeding apparatus for feeding sheet materials stacked on a mounting table one by one, and a so-called image processing apparatus such as an image reading apparatus or an image forming apparatus equipped with the apparatus. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, an image reading apparatus is provided with a feeding means for continuously feeding a document to be read and an image forming apparatus for continuously feeding a recording sheet as a recording medium. Such feeding means is provided with a sheet material spill-prevention mechanism, which prevents the occurrence of a conveyance failure such as a jam or a double feed due to the feeding of an unnecessarily large number of sheet materials, and enables stacking. It is configured to be able to feed the sheet materials one by one. With this sheet material squeezing prevention mechanism, the user can load the sheet material without paying attention to the leading end position of the sheet material.

As an example of realizing the above-mentioned rush prevention mechanism with a low-cost and simple structure, there is a sheet material feeding device as shown in FIG. 18 proposed in Japanese Patent Application No. 8-55755.
In FIG. 18, a document G stacked on a document table 100 is separated and fed by a separation roller 102, and is nipped and conveyed by a feeding roller 103 and a driven roller 104 to be conveyed.
The image is read out by 6 and discharged by a discharge roller 107a and a discharge roller 107b. In this invention, a stopper 105 having a portion for regulating the leading end of the sheet material at one end and an operating portion 105a to which the driving force is transmitted to the other end is rotatably attached, and the protrusion 10 provided on the driven roller 104
4a is configured to abut on the action portion 105a.

Accordingly, when the driven roller 104 rotates forward in the sheet conveying direction, the stopper 105 is moved to the position where the restriction is released, and when the driven roller 104 rotates reversely, the stopper 105 is moved.
Can be moved to a position where the leading end of the sheet material is regulated. Also, the rotation of the driven roller 104 is detected by rotating the driven roller 104 in the reverse direction so that the projection 104a comes into contact with the action portion 105a.

In the above arrangement, the original G is prevented from sagging between the feed roller 103 and the discharge roller 107a.
The peripheral speed of the discharge roller 107a is slightly higher than the peripheral speed of the feed roller 103. By setting the urging force of the driven roller 104 to be larger than that of the discharge roller 107b, the discharge roller
The difference in speed between the document 107a and the document G, excluding the slack, is absorbed as slippage.

However, at the moment when the trailing edge of the original G passes through the nip between the feed roller 103 and the driven roller 104, the feed roller 103
The original G is pushed from behind by the repulsive force of the rubber. This is because the feed roller 103 for the backlash of the gears existing in the reduction gear train from the motor pinion to the gear provided at the shaft end of the feed roller 103 can be additionally rotated in the transport direction. The same backlash exists for the discharge roller 107a, and the document G pushed out by the feed roller 103 causes an extra rotation in the same direction as the transport direction.

A graph of the original transport distance and time at this time is shown in FIG. 19. When the trailing end of the original G passes through the feeding roller 103 (at the point) as shown in FIG. When the document moves and stops (point (3)) and the backlash of the reduction gear train is eliminated, the document starts moving again (point (3)). The image will be disturbed during the period from.

In order to prevent this, a loading means for applying a predetermined load to the feeding roller 103 is provided.
In order to realize this load means with a low-cost and simple structure, as shown in FIG.
A torsion coil spring 109 is wound around the torsion coil 109, and the tip 109 a of the torsion coil spring 109 abuts on the fixed portion 110. In this state, the rotating shaft 108
Is rotated forward (in the direction of arrow 111), the coil spring 109 is loosened and slides on the outer peripheral surface of the rotary shaft 108, and the loose torque is used for the load on the rotary shaft 108.

[0009]

However, in the push-in prevention mechanism, it is necessary to reversely rotate the feed roller 103 to move the stopper 105 to the sheet material regulating position (hereinafter referred to as an initial position) as described above. . At this time, after the protrusion 104a of the driven roller 104 comes into contact with the stopper action portion 105a to stop the rotation, the feed roller 103 must slide and rotate with the outer peripheral surface of the driven roller 104, Larger torque is required.

When the feeding roller 103 is rotated in the reverse direction (in the direction opposite to the arrow 111) by providing the above-described load means, the torsion coil spring 109 rotates in the tightening direction.
Therefore, the tip 109a of the torsion coil spring 109 is
If the rotation shaft 108 comes into contact with the rotation shaft 108 from the opposite direction, a further load is applied to the rotation shaft 108 or the rotation shaft 108 is further tightened and locked. This may cause the motor of the feed roller 103 to lose synchronism or break.

As a countermeasure against this, it is conceivable to use a powder type torque limiter capable of applying a constant load torque even when the motor rotates forward or backward. However, the powder type torque limiter has a problem that the cost is high.

Accordingly, an object of the present invention is to provide a low-cost and simple structure that can prevent the leading end of a sheet material from sticking in.
An object of the present invention is to provide a sheet feeding apparatus and an image processing apparatus capable of preventing a disturbance of an image by avoiding pushing of a sheet material at the moment when a document is detached from a feeding roller or the like.

[0013]

A typical configuration of a sheet material feeding apparatus and image processing means according to the present invention for solving the above-mentioned problems is a sheet material mounting table capable of stacking a plurality of sheet materials and A sheet material regulating unit for regulating a front end of a sheet material placed on the sheet material placing table, and a sheet material feeding unit for feeding the separated and fed sheet material, wherein the sheet The sheet feed regulating means is moved to a position for releasing the regulation of the front end of the sheet material with the forward rotation of the sheet feeding means in the sheet conveying direction, and is moved to a position for regulating the leading end of the sheet material with the reverse rotation. And a load means for applying a load to the rotation when the sheet material feeding means rotates forward and applying no load when rotating the sheet material feeding means reversely.

[0014] With the above construction, a low-cost and simple structure for preventing the leading end of the sheet material from being rushed is required, and when the feeding roller is rotated in reverse to move the rushing prevention mechanism to the initial position. It is possible to provide a sheet feeding apparatus and an image processing apparatus that do not apply the above load.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a sheet feeding apparatus according to the present invention and an image processing apparatus provided with the sheet feeding apparatus will be described with reference to the drawings. In the present embodiment, a facsimile apparatus is illustrated as an image processing apparatus, and an automatic document feeding apparatus provided in the facsimile apparatus is illustrated as a sheet material feeding apparatus that separates and feeds a sheet material such as a document to be read. ing.

[First Embodiment] A sheet material feeding apparatus and an image forming apparatus according to an embodiment will be described in detail with reference to the drawings. As a sequence of the description, first, the schematic configuration of the facsimile apparatus will be described, and then the configuration and operation of the automatic document feeder to which the present invention is applied will be described.

[Configuration] In a facsimile apparatus as an image processing apparatus shown in FIG. 2, an upper surface cover 4 of an apparatus main body 1 has an original mounting table 4a on which an original G to be read is mounted, and a recording sheet as a recording medium. Recording sheet discharge table for discharging and loading P
A discharge tray 14 for discharging a document to the front of the apparatus body 1 and a cassette for stacking recording sheets on the bottom of the apparatus body 1
10a. Further, an operation section 33 is provided on the upper surface of the apparatus main body 1 so that various settings and operations of the apparatus can be operated.

As shown in FIG. 3, an image reading section 2 for reading an image of a document G and an image recording section 3 for recording an image on a recording sheet P are provided inside the apparatus main body 1.

[Image Reading Unit] The image reading unit 2 includes an upper cover 4 having a document placing table 4a on which a document G can be placed, and a document feeding unit which is a sheet material feeding device for separating and feeding the document G. 7, an upper document guide 9 a and a lower document guide 9 b that form a conveyance path of the document G, a contact image sensor 5 that reads image information of the document G, and a document pressing unit that presses the document G against the contact image sensor 5. 6, a discharge roller pair 8 for discharging the document G, and a discharge tray 14 for stacking the discharged document G
It is composed of

The upper cover 4 is attached to the apparatus main body 1 so as to be openable and closable so that a process cartridge 12e to be described later can be easily replaced or jammed. Also, a slider 4b slidable in the width direction orthogonal to the direction of transport of the original G is provided on the original mounting table 4a, and both ends of the original G placed on the original mounting table 4a are aligned by the slider 4b. Is available.

The contact type image sensor 5 irradiates a laser beam from the LED array as a light source to the image information surface of the original S, and reflects the reflected light from the image information surface to the sensor element by a SELFOC lens (registered trademark). It forms an image and reads image information. The document feeding unit 7 as a sheet feeding apparatus to which the present invention is applied will be described later in detail.

[Image Recording Section] The image recording section 3 includes a cassette section 10 for stacking and storing the recording sheets P, a recording sheet feeding section 11 for separating and feeding the recording sheets P from the cassette section 10, and
Image forming section 12 for forming an image on fed recording sheet P
A laser scanner 13 for irradiating the image forming section 12 with laser light as image information, a discharge tray 14 for stacking and holding recording sheets P to be discharged straight,
It is composed of a recording sheet discharge table 15 for stacking and holding the recording sheets P to be discharged and a transport guide 16 for guiding and supporting the transported recording sheets P. The rear part of the apparatus main body 1 is covered with a rear cover 17.

The cassette unit 10 provided at the bottom of the apparatus main body 1
Inside, a middle plate 10c is provided, and the middle plate 10c is pushed upward by a press-contact member 10b. As a result, the recording sheets P stacked and accommodated on the middle plate 10c are separated by a separation roller.
11a. Feeding starts and separation roller 11
a starts rotating, the recording sheet P is separated from the separation roller 11a.
The sheet is separated one by one by the separation pad 11b pressed against the sheet and is sent out along the separation pad guide 11c.

The recording sheet P is reversed and transported by a transport path formed by a cover-side U-turn guide 17a disposed on the rear cover 17 and a main-unit U-turn guide 17b disposed on the apparatus main body 1 side. 11d and the transport rollers 11e and 11f which are pressed and contact with the transport rollers 11e and rotate accordingly. The transport roller 11d transports the recording sheet P between the photosensitive drum 12a of the image forming unit 12 and the transfer unit 12f in synchronization with the photosensitive drum 12a on which an image (toner image) described later is formed.

Incidentally, the cassette 10a is provided with a movable rear end regulating plate 10d for regulating the rear end surface in accordance with the size of the recording sheets P to be stacked. The cassette 10a in this embodiment has a capacity of approximately 25
The number of sheets is about 0, and the sheet can be pulled out in the front direction of the apparatus body 1 (front loading method). Further, there are two types of recording sheets P that can be stacked and accommodated: A4 size and letter size.

In the image forming section 12, a photosensitive drum 12a as an image bearing member is provided inside a process cartridge 12e.
And a charging unit 12b for uniformly charging the photosensitive drum 12a, a developing unit 12c for developing an electrostatic line image formed on the photosensitive drum 12a,
The cleaning means 12d is integrated. The process cartridge 12e is configured to be detachable from the apparatus main body 1.

When an image is formed, the photosensitive drum 12a is charged in advance by the charging means 12b. Next, a laser beam is emitted from the laser beam oscillator 13a of the laser scanner 13 based on the image signal. The laser light is irradiated on the photosensitive drum 12a by the polygon mirror 13b and the return mirror 13c, and forms an electrostatic latent image on the surface thereof. The formed electrostatic latent image is visualized by the developing means 12c, whereby a toner image is formed on the surface of the photosensitive drum 12a.

A transfer means 12f is in contact with the photosensitive drum 12a, and is configured to transfer a toner image to a recording sheet P conveyed to a nip between the photosensitive drum 12a and the transfer means 12f. As described above, the recording sheet P is synchronized with the photosensitive drum 12a by the transport roller 11d,
The recording sheet P is conveyed so that the leading end of the recording sheet P coincides with the leading end of the toner image.

The recording sheet P onto which the toner image has been transferred is conveyed along a conveyance guide 16, and the toner image is fixed by applying heat and pressure by fixing means 12g.
The recording sheet P on which the image has been fixed is discharged and stacked on the discharge tray 14 or the recording sheet discharge table 15 by the discharge roller 18.

When a jam occurs during the recording operation, the cover such as the upper cover 4 and the rear cover 17 is opened so that the recording sheet P staying inside the apparatus can be easily taken out. Has become.

[Control System] FIG. 4 is a system block diagram of the facsimile apparatus. In FIG. 4, a CPU 21 is a system control unit and controls the entire apparatus. The control program of the CPU 21 is stored in the ROM 22, and the
AM23 is used as a work area. Storage memory 24
Is composed of a DRAM or the like, and stores image data. The registration unit 25 is configured by an SRAM or the like, and stores and reads a set value when performing operation control. The encoding / decoding processing unit has a communication 26 and a reading / recording 29,
Each of them performs a code decoding process exclusively.

The operation unit 33 includes a display unit, a keyboard, and the like, and is used by an operator to perform various input operations. The MODEM (modulator / demodulator) 27 modulates and demodulates a transmission / reception signal of the facsimile apparatus. The NCU (network control unit) 28 has a function of transmitting a selection signal (dial pulse or tone dial) to the communication line 30, and performs an automatic incoming call operation and a line control operation by detecting a ringing tone.

The scanner 32 (image reading section 2) includes a contact image sensor 5 (CS), a document feeding section 7, and the like.
The original is read optically and converted into electrical image data. This image data is subjected to correction processing by the image processing unit 31 and is output as high-definition image data.
The recording unit 34 (image recording unit 3) is configured by a laser beam printer, an ink jet printer, or the like, and outputs high-definition image data generated by the encoding / decoding processing unit 29.

[Document Feeding Section] Next, the configuration and operation of the document feeding section 7 as a sheet feeding apparatus to which the present invention is applied will be described. As shown in FIGS. 5 to 8, the document feeder 7 is driven by a separation roller 7a, a pre-pressing arm 7b pressed against the separation roller 7a, and a feed roller 7c as a driving rotating body. The driven roller 7d as a driven rotating body and the leading end of the original document G placed on the document table 4a are regulated.
It is composed of a stopper 7h which is a sheet material regulating means for releasing.

The discharge roller pair 8 disposed downstream of the close contact type image sensor 5 is composed of a discharge roller 8a and a driven roller 8b which is pressed against and driven to rotate.
The driven roller 8b and the driven roller 7d are pressed by a discharge roller 8a and a feed roller 7c by a leaf spring 7g.

A loading means 40 is provided on the rotating shaft 43 of the feeding roller 7c shown in FIG. The loading means 40 includes, as shown in FIG. 1, a one-way clutch 41 fitted on the rotating shaft 43,
The torsion coil spring 42 is fitted on the outer peripheral surface of the one-way clutch 41. One-way clutch 41 is a rotating shaft
Direction 43 is the direction in which the original G is transported (arrow A direction)
The rotation shaft 43 is configured to lock so as not to apply a load to the rotating shaft 43 when performing reverse rotation.

The torsion coil spring 42 extends one terminal 42a, and the rotation of the torsion coil spring 42 is restricted by bringing the terminal 42a into contact with the fixing portion 46. The torsion coil spring 42 has an inner diameter smaller than the outer diameter of the one-way clutch 41 by a predetermined amount, and when the rotation shaft 43 rotates forward, the torsion coil spring 42 loosens and slides on the outer peripheral surface of the one-way clutch 41. . This frictional resistance is
43, it is possible to prevent the feed roller 7c from moving due to the backlash play,
Image disturbance can be prevented.

Even if the rotating shaft 43 rotates in the reverse direction, the one-way clutch 41 idles.
Even if a rotates reversely by one rotation and abuts against the fixed portion 46, no further rotational force is transmitted, so the rotating shaft 43 locks due to the tightening of the torsion coil spring 42, and the motor loses synchronism or the drive gear train is destroyed. Can be prevented.

As shown in FIG. 8, the driven roller 7d is integrally provided with a projection 7d1 for switching the position of the stopper 7h between the position for regulating the leading end of the sheet material and the position for releasing the same. The stopper 7h is attached so as to be rotatable about a shaft 7h4, has a regulating portion 7h5 at one end for regulating the leading end of the sheet material, and has an operating portion at the other end on which the protrusion 7d1 acts. The action portion has a hook portion 7h1 on the lower surface, a positioning portion 7h2 on the upper surface, and a groove 7h3 at a position corresponding to the axis of the driven roller 7d.

Therefore, when the driven roller 7d rotates forward, the protrusion 7d1 comes into contact with the positioning portion 7h2 to rotate the stopper 7h, and the regulating portion 7h5 moves upward to move the document placing table 4
The restriction on the leading end of the original G placed on the document a is released. When the driven roller 7d rotates in the reverse direction as shown in FIG.
d1 comes into contact with the hooking portion 7h1 to move the regulating portion 7h5 to the initial position and stop the rotation of the driven roller 7d as shown in FIG. The stop of the driven roller 7d is used for detecting the position of the driven roller 7d.

When the document G is placed on the document table 4a, the document G is first sandwiched between the separation roller 7a and the preliminary pressure contact arm 7b pressed against the document G, and then returned to the initial position. The stopper 7h, and does not enter any further. Next, when the document conveyance is started, the stopper 7h is moved to a position where the regulation of the front end of the document is released by the protrusion 7d1 of the driven roller 7d, so that the document G on the document table 4a is separated from the separation roller 7a.
And the pre-pressing arm 7b pressed against it, the sheets are separated and fed one by one. Then, the separated and fed original G is sent to the contact type image sensor (CS) 5 by the feed roller 7c and the driven roller 7d.

As described above, during the reverse rotation, the driven roller 7d stops rotating. Therefore, when a predetermined torque T3 or more is applied, the feed roller 7c, which is a driving rotating body, rotates the outer peripheral surface of the driven roller 7d. Slip and start spinning. Accordingly, the driven roller 7d and the stopper 7h can be reliably returned to the initial positions, and the stopper 7h is not lifted when the document G is placed by placing the document feeding unit 7 on standby in this state. It is possible to reliably prevent the original G from being pushed in.

The slip torque between the feed roller 7c and the driven roller 7d is set to T2, and the driven roller 7d rotates forward to release the stopper 7h when the maximum number of documents G are placed on the document table 4a. Assuming that the release torque of T1 is T1, T1
It is set so that the relationship of <T2 <T3 holds. Note that the slip start torque T3 is set to a value in a range where the motor does not step out.

Here, since the one-way clutch 41 is attached to the rotating shaft 43, no load is added at the time of the reverse rotation, so that the feed roller 7c applies only the torque T2 to the load caused by slippage with the driven roller 7d. Can be For example, if a torque limiter that applies a load in the normal and reverse directions is provided, a larger load will be applied during reverse rotation than during forward rotation. It becomes necessary to mount a motor, which increases the production cost. However, the configuration according to the present invention has an effect that an appropriate motor can be selected because the load by the torque limiter is not involved during the reverse rotation.

As shown in FIG. 11 (a), when the driven roller 7d rotates in the reverse direction, the projection 7d1 may fall into the groove 7h3 depending on the timing. In this state, the stopper 7h cannot descend downward,
It will be in a state of rising. In order to avoid this, after the driven roller 7d is rotated in reverse, FIG.
As shown in (b), if the rotation is made forward (within one rotation), the stopper 7h can be lowered by its own weight. After that, the driven roller 7d is again rotated in the reverse direction (within 1.5 rotations).
By doing so, the driven roller 7d and the stopper 7h can be reliably returned to the initial positions as shown in FIG.

A DS sensor 19a for detecting the presence or absence of a document and a DES sensor 19b for detecting the trailing end of the document are mounted on the upstream side of the feeding roller 7c, and based on information from these sensors 19a. Various operations described below are controlled.

[Operation] Next, the operation of the apparatus main body 1 will be described. First, the operation of initializing the stopper 7h will be described, and then the operation of the entire image processing apparatus will be described focusing on the initialization operation.

[Initialization Operation] The initialization operation of the stopper 7h will be described with reference to FIGS. 12, 14, and 15. FIG. As shown in FIG. 14, the control unit 20 drives the motor M via the motor driver M1 based on signals from the DS sensor 19a and the DES sensor 19b, and
a, The driving force is transmitted to the feeding roller 7c and the like. The image information acquired from the contact type image sensor 5 (CS) is subjected to correction processing by the image processing unit 31 and is passed to the control unit 20.

When the original G is placed on the original placing table 4a as shown in FIG. 12A, the DS sensor 19a is turned ON and the initialization operation is started. FIG. 15 shows the stopper 7h.
5 is a flowchart showing the stiffness of the initialization operation of FIG. The initialization operation is performed by rotating the motor M in the order of reverse rotation (arrow a), forward rotation (arrow b), and reverse rotation (arrow c), and similarly rotates the feed roller 7c by the driving force. .

That is, first, the speed of the motor M is set (S40).
1) Thus, the number of steps S1 to be reversely rotated is determined (S402). And the number of steps S1 minute motor M
Are rotated in reverse (S403-S405). As a result, the protrusion 7d1 of the driven roller 7d comes into contact with the hook 7h1 to move the stopper 7h to the initial position.

However, as described above, there is a case where the timing is kept rising depending on the timing. Therefore, the number of steps S2 is determined (S40
6), the motor M is rotated forward by the number of steps S2 (S4).
07 to S409).

After that, the number of steps S3 for reverse rotation is determined (S410), and the motor M is rotated reversely (S411 to S413) for step S3 to enter a standby state. As a result, the protrusion 7d1 of the driven roller 7d comes into contact with the hook 7h1, and the stopper 7h moves to the initial position as shown in FIG. As a result, the document table 4
The driven roller 7d and the stopper 7h can be reliably returned to the initial position even after the upper cover 4 and the like having the a are opened and the jam is removed, and components such as a sensor for detecting the opening and closing of the upper cover 4 are provided. There is no need to use it, and the apparatus configuration can be reduced in cost.

The number of rotation steps of the motor varies depending on the step angle of the motor.
It is 0 steps. That is, the amount by which the driven roller 7d rotates reversely with respect to the document conveying direction (arrow c) is within 1.5 rotations, and the amount of forward rotation (arrow b) with respect to the document conveying direction is within one rotation. I have to. This allows
The load on the motor and the abrasion of the feed roller 7c are minimized, the durability is improved, and the time required for initialization can be minimized.

[Overall Operation] The overall operation of the image processing apparatus will be described with reference to FIGS. 12 to 14, 16 and 17, focusing on the initialization operation of the stopper 7h. FIG. 16 is a flowchart showing a flow of processing from power-on to a standby state of the image processing apparatus, and FIG. 17 is a flowchart showing a flow of reading control of the image processing apparatus.

First, as shown in FIG. 16, when the power is turned on, the display unit in the operation unit 33 (see FIG. 2) is initialized, and a display such as "PLEASE WAIT" indicating the start-up operation is performed (FIG. 16). S201). Next, the image recording unit 3 is initialized, and it is monitored that the image recording unit 3 enters a standby state (S203). At this time, a data error is detected (S204).
If so, all the image memories are cleared, the image management data is initialized, and a memory clear list is output (S205).

The checksum of the backup RAM for managing the registered data and the like is calculated and compared with the numerical value in the checksum storage area (S206). Here, when a data error is detected (S207), the default value of the registration data is stored again in the registration area (S20).
8).

When the sensor output indicating the presence or absence of a document indicates that there is no document (S209), a white background mylar serving as a white background reference is read and prescanning is performed to store it in the RAM of the scanner unit as shading correction data (S21).
0). Then, the above-described stopper initialization control (FIG. 15)
Reference) (S21I). After initialization is completed,
The state shifts to a state in which key input from the operator can be accepted (standby state), and clock display and the like are performed.

While the output of the DS sensor 19a for detecting the presence or absence of a document is OFF (S301), the image reading section 2 is in a reading standby state. And the output of the DS sensor 19a is ON
Then, the reading control is started.

The DES sensor 19b for detecting the rear end of the original is
In the case of N (S302), there is a possibility that the document G is placed beyond the restricting portion 7h5 of the stopper 7h. In this case, since the initialization of the stopper 7h is meaningless, the initialization operation is not performed. Also, since there is a possibility that the sensor reaches the vicinity of the contact type image sensor 5, the pre-scan operation is not performed.

When the DS sensor 19a is ON and the DES sensor
When 19b is OFF, the stopper 7h is initialized (S
303), a pre-scan operation is performed (S304). Then, the motor M is rotated forward, and the driven roller 7d is rotated in the document conveying direction as shown in FIG. Then, the protrusion 7d1 of the driven roller 7d is engaged with the hook 7h of the stopper 7h.
1 and the stopper 7h is lifted and moved to a position where the regulation of the leading end of the document is released. Therefore, the document table 4a
Is placed between the separation roller 7a and the preliminary press-contact arm 7b, is conveyed by the feed roller 7c and the driven roller 7d, and is brought into close contact with the image sensor 5 (CS).
(S3O5), and the image reading is started.

When the stopper 7h moves to the position where the restriction is released, as shown in FIG. 13A, the stopper 7h rides on the upper surface of the uppermost original G placed by its own weight. Thereafter, each time the driven roller 7d rotates and the projection 7d1 comes into contact with the hook 7h1, it moves upward as shown in FIG. 13B until all the placed originals G are fed. This vertical movement is repeated.
When all the originals G pass through the stopper 7h, the stopper 7h is lowered by its own weight.

When the original G is fed to the reading position, the original G
The image data is read while carrying the image data for one line, and DMA-transferred to the image buffer. The image data is encoded line by line and stored in the image memory (S306). DE
Until the S sensor 19b is turned off and the effective range of one document G is completely read, the reading operation for each line (S
306 to S3O7) are repeated.

If an error occurs during the reading operation of one original G (S3O8), the DS sensor 19a is turned off.
(S3I4) and when the DES sensor I9b is ON (S315), that is, when the rear end of the document G remains in the document feeding section 7, a predetermined amount of paper is fed, and the erroneous document is carried out (S3I6). If the main feeding process is not performed, the trailing end of the document remains sandwiched between the document feeding units. At this time, if the stopper 7h is initialized, the document is entangled and may be damaged. Therefore, after feeding processing for preventing entanglement, an error alarm is sounded and an error display is displayed on the display of the operation unit 33 (S3I7). ).

If no error occurs, the original trailing edge sensor I9
When b is turned ON and the end of the reading range for one sheet is detected, the number of reading lines for one sheet is stored in the image management data (S309). The next manuscript is set and DS
When the sensor I9a is ON, the reading control for one sheet (S3O5 to S309) is repeated (S3I0).
If there is no next original G, the read page number of the original G is written in the image management data, and the reading process of one file is completed (S311). After completely unloading the original (S312), the stopper 7 is moved as shown in FIG.
The initialization operation of h is performed (S3I3), and the process returns to the reading standby state as shown in FIG.

As described above, the initialization operation of the stopper 7h is performed a plurality of times, specifically, twice when the original G is placed and after the original is fed, so that the driven roller 7d and the stopper 7h are always in the initial position. To the standby state.

In the above embodiment, the load means 40
Is provided only on the rotating shaft 43 of the feed roller 7c, but may be provided on the rotating shaft of the discharge roller 8a.

In the above embodiment, a facsimile apparatus having a transmission / reception function has been exemplified as an image processing apparatus. However, the present invention is not limited to this. For example, an image output terminal of an information processing device such as a computer, The present invention may be applied to a copying apparatus combined with a reader or the like, and similar effects can be obtained by applying the present invention to a sheet material feeding apparatus provided in these apparatuses.

In the above-described embodiment, a document to be read is used as an example of a sheet to be fed, but a recording sheet to be printed may be used. The same effect can be obtained even if the present invention is applied to a feeding device.

[0069]

As described above, the sheet feeding apparatus and the image forming apparatus according to the present invention are provided with the load means for applying a load to the sheet material feeding means when rotating forward and applying no load when rotating reversely. As a result, it is possible to prevent the back end of the drive gear train from being excessively rotated by the backlash of the drive gear train at the moment when the trailing edge of the document comes off the sheet feeding means. It can be carried out.

When the sheet feeder is rotated in the reverse direction to move the sheet feeder to the position where the sheet feeder is controlled, the load by the load is not applied. Only the torque to slide with a certain driven roller is needed. Therefore, it is not necessary to cope with an unexpectedly large torque, and there is an effect that an appropriate motor can be selected.

Since the load means is constituted by a one-way clutch and a torsion coil spring, the apparatus can be realized with a low cost and simple structure.

[Brief description of the drawings]

FIG. 1 is a perspective view of a load unit fitted on a feed roller shaft of a sheet material feeding device according to the present embodiment.

FIG. 2 is an external perspective view of the image processing apparatus.

FIG. 3 is a sectional view of the image processing apparatus according to the embodiment.

FIG. 4 is a system block diagram of the image processing apparatus.

FIG. 5 is a cross-sectional view of a sheet material feeding device.

FIG. 6 is a bottom plan view of a path of the sheet material feeding device.

FIG. 7 is a top plan view of a path of the sheet feeding apparatus.

FIG. 8 is a perspective view illustrating a relationship between a feeding roller, a driven roller, and a stopper in the sheet material feeding device.

FIG. 9 is an explanatory diagram of a theory in which a slip between a feed roller and a driven roller is used as a torque limiter.

FIG. 10 is an explanatory diagram showing a method of fixing a stopper in the sheet feeding device during standby.

FIG. 11 is a diagram illustrating the operation of a mechanism for preventing the stopper from being kept up in the sheet material feeding device.

FIG. 12 is a diagram illustrating the operation of the sheet material feeding device.

FIG. 13 is an operation explanatory view of the sheet material feeding device.

FIG. 14 is a block diagram of a control system of the sheet feeding apparatus.

FIG. 15 is a flowchart illustrating a flow of initialization control of a stopper of the sheet feeding apparatus.

FIG. 16 is a flowchart illustrating a flow of processing from power-on to a standby state of the image processing apparatus.

FIG. 17 is a flowchart illustrating a flow of reading control of the image processing apparatus.

FIG. 18 is an explanatory diagram of a change in a feeding speed in a sheet material feeding device according to a conventional example.

FIG. 19 is a diagram illustrating the movement of a document when the feeding speed changes according to the conventional example.

FIG. 20 is a perspective view of a load unit fitted on a feeding roller shaft of a sheet material feeding device according to a conventional example.

[Explanation of symbols]

 G: Document P: Recording sheet 1: Device body 2: Image reading unit 3: Image recording unit 4: Top cover 4a: Document mounting table 5: Contact image sensor 6: Document pressing unit 7: Document feeding unit 7a: Separation Roller 7b Preliminary pressure contact arm 7c Feed roller 7d Follower roller 7d1 Projection 7g Leaf spring 7h Stopper 7h1 Hook 7h2 Positioning part 7h3 Groove 7h4 ... Shaft 7h5 ... Restriction part 8 ... Discharge roller pair 8a … Discharge roller 8b… Follower roller 9a… Upper document guide 9b… Lower document guide 10… Cassette unit 10a… Cassette 10b… Press-contact member 10c… Medium plate 10d… Rear end regulating plate 11… Recording sheet feeding unit 11a… Separation roller 11b … Separation pad 11c… Separation pad guide 11d… Cover roller 11e… Cover roller 11f… Cover roller 12… Image forming unit 12a… Photoconductor drum 12b ... Charging means 12c ... Developing means 12d ... Cleaning means 12e ... Process cartridge 12f ... Transfer means 13 ... Laser scanner 13a ... Laser beam oscillator 13b ... Polygon mirror 13c ... Mirror 14 ... Discharge tray 15 ... Recording sheet discharge table 16 ... Conveyance guide 17 … Rear cover 17a… U-turn guide 18… Discharge roller 19a… DS sensor 19b… DES sensor 21… CPU 22… ROM 23… RAM 24… Storage memory 25… Registration unit 26… Communication encoding / decoding processing unit 27… MODEM 28 ... NCU 29 ... Recording encoding / decoding processing section 30 ... Communication line 31 ... Image processing section 32 ... Scanner 33 ... Operation section 34 ... Recording section 40 ... Loading means 41 ... One-way clutch 42 ... Torsion coil spring 42a ... Terminal 43 ... Rotating shaft 46… fixed part

Claims (8)

[Claims] A sheet mounting table on which a plurality of sheets can be stacked; sheet material regulating means for regulating a tip of the sheet mounted on the sheet mounting table; A sheet material feeding device having a sheet material feeding means for feeding the sheet material, wherein the sheet material regulating means changes the sheet material as the sheet material feeding means rotates forward in the sheet material conveying direction. The sheet material is moved to a position where the regulation of the leading end is released, and is moved to a position where the leading end of the sheet material is regulated as the sheet rotates in the reverse direction. A sheet material feeding device comprising a load means that does not apply a load when rotating. 2. The apparatus according to claim 1, wherein said load means is a one-way clutch fitted on a rotating shaft of said sheet material feeding means, and a torsion coil spring fitted on an outer periphery of said one-way clutch. Item 2. The sheet material feeding device according to Item 1. 3. The torsion coil spring of the load means has an extended terminal, and the terminal comes into contact with a fixing portion provided on the image processing apparatus main body and loosens by sliding on the outer peripheral surface of the one-way clutch. The sheet feeding device according to claim 2, wherein the sheet feeding device is configured. 4. The sheet feeding means comprises a driving rotator and a driven rotator that is pressed against the driving rotator and is driven to rotate. The driven rotator has a protrusion, and the protrusion has a protrusion. 4. The sheet material restricting means is configured to switch between a position for regulating the leading end of the sheet material and a position for releasing the leading end of the sheet material according to reverse rotation and forward rotation of the sheet material feeding means. The sheet material feeding device according to the above. 5. The driven rotator stops rotating by the protrusion contacting the sheet material regulating means when rotating in the reverse direction, and the driving rotator slides on the outer peripheral surface of the driven rotator to reverse the rotation. The sheet feeding apparatus according to claim 4, wherein the sheet feeding apparatus is configured to maintain rotation. 6. The sheet material feeding device according to claim 5, wherein the stop of the driven rotator when the protrusion contacts the sheet material regulating means is used for detecting the position of the driven rotator. apparatus. 7. The rotation control for returning the sheet material regulating means to the initial position is performed by rotating the sheet material feeding means in the reverse direction with respect to the sheet material conveying direction, then rotating forward, and then further rotating in the reverse direction. The sheet material feeding device according to any one of claims 1 to 6, characterized in that: 8. An image processing apparatus having at least one of a reading unit for reading an image and a recording unit for recording an image, wherein a sheet material such as a document to be read or a recording sheet to be recorded is provided. The sheet material feeding device according to any one of claims 1 to 7, wherein the sheet material feeding device separates and feeds the sheet material one by one to the reading means or the recording means. Characteristic image processing device.