JP2000242046A - Automatic original feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an automatic original feeder constituted so that a curled original can be pressed without giving supply resistance according to the number of stacking sheets (height) of the originals set at a supply table and a document is prevented from being skewed because it gets over a side fence when it is supplied. SOLUTION: A pressing plate 82b pressing the upper surface of the original housed in the supply table 6 is provided in the side fence 81b. Then, the plate 82b is constituted so that an adjustment means (a pressing plate motor 91b, a rack 89b, a pinion 92b and the like) can be moved in an upper and a lower directions based on information detected by an original height detection means (a document height sensor 95, a sensor feeler 96, an original height feeler 98 and the like).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an automatic document feeder in an image forming apparatus such as a copying machine.

[0002]

2. Description of the Related Art In a conventional automatic document feeder of an up-feed type mounted on a copying machine main body, when a document is stacked on a feed table with an image side facing upward, a document set is detected by a document set sensor. Is done. Then, when the document set is detected, the bottom plate of the sheet feeding table is raised in the sheet feeding preparation operation, and the upper surface of the document is pressed against the call roller. When the user presses the start button of the apparatus main body after ascending to the sheet supply appropriate position in this state, a copy operation is started.

The sheet feeding table is provided with side fences for regulating the width direction of the document bundle (the direction perpendicular to the sheet feeding direction). 11 and 12, a front fence (hereinafter, referred to as a front fence) 75a of a side fence slidable in the width direction along a rail 72, and fixed to face the front fence 75a. A rear fence (hereinafter, referred to as a rear fence) 75b of the arranged side fence, and a front pressing member 7 provided at an upper end of the front fence 75a in the sheet feeding direction.
7a, and a rear pressing member 77b provided above the front end of the rear fence 75b in the paper feeding direction. The pressing members 77a and 77b such as the roof are constituted by, for example, a mold plate, a leaf spring, a film, and the like. When the original is curled on the side fence side during paper feeding and skewed to the right and left with respect to the transport direction, the document is prevented from rising, and the original is prevented from being fed obliquely beyond the side fence. Is what you do.
FIG. 12 is a schematic diagram viewed from the direction A in FIG.
Related devices of this type include, for example,
No. 147433.

[0004]

In the above prior art,
The position of the pressing member provided on the side fence (the height from the upper surface of the paper feed table) is fixedly set in accordance with the maximum number of documents to be loaded on the paper feed table. When the number of documents is small, the above-described operation cannot be performed, and there is a problem that the curled document skews over the side fence during paper feeding. If the position of the pressing member is set to be lower and fixed so as to be smaller than the maximum number of sheets to be stacked, the pressing member itself serves as a sheet feeding resistance, causing the document to be skewed at the time of sheet feeding, or to a side position after the document is set. Inconveniences such as not being able to regulate the horizontal direction of the document by sliding the fence are caused.

SUMMARY OF THE INVENTION An object of the present invention is to improve such a problem and to curl a curled document without causing a sheet feeding resistance in accordance with the number of sheets (height) set on the sheet feeding table. The object of the present invention is to provide an automatic document feeder capable of preventing a skew from occurring over a side fence during paper feeding.

[0006]

According to the first aspect of the present invention,
Storing means for storing a plurality of documents in a stacked state, provided in the storing means, a width direction regulating means for regulating the width direction of the documents accommodated in the storing means, provided in the width direction regulating means, Pressing means for pressing the upper surface of the document stored in the storing means, and adjusting means for adjusting the height position of the pressing means arbitrarily by moving the pressing means in the up-down direction; The upper surface of the document is pressed according to the stacking height of the stored document.

According to a second aspect of the present invention, in the first aspect, the adjusting means moves the pressing means in a vertical direction based on input information input by a switch operation.

According to a third aspect of the present invention, there is provided a document height detecting means for detecting whether or not a pressing means is provided at a stacking height of the documents stored in the storing means, and Control means for controlling the amount of movement by which the adjusting means moves the pressing means in the vertical direction based on the detection information.

According to a fourth aspect of the present invention, in the third aspect, the control means lowers the pressing means to contact the upper surface of the document based on the detection information of the document height detecting means, and then controls the pressing means. The distance between the upper surface of the document and the pressing means is maintained by raising the document by a predetermined amount.

According to a fifth aspect of the present invention, in the fourth aspect, a home position detecting means for detecting whether the pressing means is at a home position, and a pressing means when all the originals stored in the storing means have been fed. Control means for raising the means to the home position.

According to a sixth aspect of the present invention, in the first to fifth aspects, the adjusting means includes a driving motor for driving the pressing plate in a vertical direction, and converting a rotational force of the driving motor into a vertical movement of the pressing plate. And a rack and pinion mechanism.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. [First Embodiment] FIGS. 1 and 2 show the configuration of an automatic document feeder mounted on the main body of a copying machine according to a first embodiment of the present invention, and FIG. 2 shows a configuration of a control unit.

Automatic document feeder (hereinafter referred to as ADF)
1 is mounted on the main body 2 of the image forming apparatus (copier). The ADF 1 includes a paper feed unit 70 including a paper feed / separation mechanism including a separation belt 9 and a separation roller 10,
3 and a discharge unit 90 including the discharge roller 16 and the like. The ADF 1 also receives a copy start signal (FIG. 2) transmitted from the main unit 2 by pressing a start button (not shown) of the operation unit 43 of the main unit 2.
Input means (CPU) for receiving and inputting a paper feed start signal shown in FIG.
29 etc.). The feed start signal raises the bottom plate 7 to a predetermined position (a position in contact with the upper surface of the document), starts the operation of rotating the call roller 8 and starts the operation of feeding the document 5 on the feed table 6. is there. Also, the CPU 29
, The separation roller 9, the separation belt 9, the separation roller 10, the pull-out roller 11, and the conveyance roller 12
Is driven by a paper feed motor (configured with a stepping motor in this embodiment) 30.

In the paper feed section 70, the sheet-shaped originals 5 are stored in a stacked state, and both side edges of the original 5 in the width direction are regulated by side fences (= width direction regulating means) 81. The configured paper feed table 6 (=
Accommodation means), an original set sensor 21 for detecting that an original is set on the paper feed table 6, a call roller 8 for contacting the uppermost original contained in the paper supply table 6 and feeding the original. And a bottom plate 7 which lifts the document feeding direction side of the document 5 accommodated in the sheet feeding table 6 and rises to a position where the top document is brought into contact with the call roller 8.

The front end of the side fence 81 is shown in FIG.
And a front-side pressing plate (= pressing means) 82a
Are provided with rails 83a and 83b for slidably moving the rails, and the front pressing plate 82a is provided with a slide member 85 that slides on the rails 83a and 83b. The front pressing plate 82a is fixed to the leaf spring 84 by screws together with the slide member 85, and can be moved up and down by sliding on the rails 83a and 83b by the slide member 85. It is configured so that it does not fall due to resistance.

With such a configuration, the user presses the upper surface of the original on the paper feed table 6 by setting the front pressing plate 82a at the original height when the original is set. FIG.
In the figures, the front fence (hereinafter referred to as the front fence) 81a and the front pressing plate 82a of the side fence are shown, but the other (the rear fence and the rear pressing plate (= pressing means) of the side fence 81) is similarly configured. ing. In the present embodiment, the rails 83a and 83b, the slide member 8
5, the leaf spring 84, etc. constitute the adjusting means.

The shapes of the front and rear pressing plates are not limited to this embodiment, but may be, for example, as shown in FIG. In the configuration of FIG. 3A, a plate-like rail 83 and a pressing plate 82 c (mold formation) that can slide and sandwich the rail 83 are provided inside the side fence, and the pressing plate 82 c is vertically moved along the rail 83. It is possible to move. In this case, the dimensional tolerance between the rail 83 and the rail receiving portion of the pressing plate 82c is made strict to cause friction. In the configuration of FIG. 3B, the rail receiving portion 85a (mold formation) of the pressing plate 82d and the pressing portion (leaf spring) 84
a is formed separately, and the leaf spring 84a is screwed and fixed. The rail shape inside the side fence is the same as that in FIG. In the configuration of FIG. 3C, the rail receiving portion 85b (mold formation) of the pressing plate 82e and the pressing portion (leaf spring) 84b are separately formed, and the leaf spring 84b is formed.
Is fixedly inserted into the rail receiving portion 85b. The rail shape inside the side fence is the same as that in FIG. In the configuration of FIG. 3D, the rail receiving portion 85c (mold formation) of the pressing plate 82f and the pressing portion (thickness 0.2)
(A 0.3 mm film) 84c is formed separately, and the film 84c is bonded and fixed to the rail receiving portion 85c. The rail shape inside the side fence is shown in Fig. 3.
Same as (a).

Further, the CPU 29 obtains the detection information from the original set sensor 21, the paper feed position sensor 50, and the like, and sends the bottom plate 7 via a motor driver (Tr array) to the bottom plate up / down motor (in this embodiment, a stepping motor). Configuration) 3
3 is driven up and down by driving control. That is, the bottom plate 7 is configured to be able to move up and down in the a and b directions about the rotation fulcrum 7a by driving the bottom plate up / down motor 33.

The call roller 8 is held by a call roller bracket (not shown). The call roller bracket has one of two levers (consisting of two arms) rotatable around a paper feed drive shaft (not shown). Arm ends are in contact. Further, the other arm end of the lever is in contact with a cam (not shown) provided on the drive shaft of the motor 35 for raising and lowering the roller. The cam is rotated by driving the motor 35 for raising and lowering the call roller, so that the call roller 8 moves up and down in the c and d directions.

With such a configuration, when the document is not set, the call roller 8 is lifted in the direction c by the lever. When the document set sensor 21 detects a document set, the urging of the lever is released by the rotation of the cam driven by the motor 35 for raising and lowering the call roller, and the call roller 8 descends in the direction d by its own weight. When the bottom plate 7 is raised in the direction a by the driving of the bottom plate up / down motor 33, the call roller 8 which has been lowered as described above comes into contact with the upper surface of the original on the bottom plate 7 and is pushed up in the direction c.
The paper feed sensor 14 is configured to determine the appropriate paper feed position (the raised position of the bottom plate 7) by detecting the call roller 8.

The paper feed belt 9 is driven by a paper feed motor 30 in the paper feed direction.
, Which is configured to perform a separating operation of separating the lowermost document from the uppermost document and feeding only the uppermost document. The separation roller 10 is supported on a separation roller shaft via a torque limiter (not shown). When an external force greater than the torque of the torque limiter is applied to the separation roller 10, the separation roller 10 rotates in the opposite direction to the sheet feeding, and Even if a smaller external force is applied, the sheet is not rotated in the opposite direction to the sheet feeding.

The feed shaft of the feed roller around which the paper feed belt 9 is stretched is provided with a feed gear with a one-way clutch, and the feed shaft is configured to support the feed roller and the feed gear with the one-way clutch. Have been. Since the roller shaft of the call roller 8 is connected to the one-way clutch feed gear via a gear, when the paper feed motor 30 is driven in the paper feed direction, the paper feed belt 9 rotates in the paper feed direction and , The call roller 8 also follows the sheet feeding direction. On the other hand, when the paper feeding motor 30 is driven in the direction opposite to the paper feeding direction, the driving force is not transmitted to the paper feeding belt 9 by the operation of the one-way clutch, and the driving force is not transmitted to the calling roller 8. ,
The call roller 8 does not follow.

The pull-out roller 11 is driven by a paper feed motor 30, and conveys the original conveyed by the paper supply belt 9 to the conveying roller 12 after the original is separated.

The pull-out sensor 51 is an optical reflection type sensor, which detects the original conveyed by the pull-out roller 11 and detects the length of the original from the motor pulse by detecting the leading and trailing edges of the original. Also used to detect. When the pull-out sensor 51 detects the leading edge of the original, the operation of separating the original ends, and the original is conveyed onto the contact glass 19 via the conveying roller 12. At this time, the driving direction of the paper feeding motor 30 is changed from the normal rotation during the separating operation to the reverse rotation. As a result, the drive to the call roller 8 and the paper feed belt 9 is not transmitted as described above, and the pull-out roller 1
1 and the transport roller 12 are driven to rotate in the direction of transporting the document, and the separation roller 10 is driven to rotate in the direction opposite to the transport of the document. When the original is transported by the pull-out roller 11 and the transport roller 12, the call roller 8 presses the upper surface of the original bundle, so that the lower original can be prevented from being entrained and transported to the separation unit.

Further, the original width sensor 62 is set at 3 in the depth direction.
This is an optical reflection type sensor arranged in a row and used for detecting the width of a document.

The registration sensor 15 is connected to the transport roller 1.
2 is an optical reflection type sensor for detecting the original conveyed by the scanner 2 and is used as a timing sensor for stopping the original on the contact glass 19 and JA.
It also serves for M detection and document length detection.

The transport belt driving roller 52 of the transport section 80 has an endless belt (transport belt) 1 made of rubber or cloth.
The transport belt 13 is rotated by driving a transport belt driving roller 52 by a transport motor (in this embodiment, a stepping motor) 31.

The transport belt 13 is attached to an original scale 20.
And the contact belt 19 and the conveyor belt 1
The document enters between the contact glass 3 and the contact glass 19, and the document includes the contact glass 19, the document, and the transport belt 13.
The document is conveyed over the contact glass 19 due to the difference in friction coefficient between the document and the document. The end of the original scale 20 is slightly higher than the upper surface of the contact glass 19, and the skew is corrected by setting the original end against the end of the original scale 20 to correct the skew. Is configured to read.

In the paper discharge section 90, a paper discharge sensor (in the present embodiment, constituted by an optical reflective sensor) 18
Is for detecting a document conveyed by the conveyance belt 13. On the other hand, the detection information of the reversing sensor (constituted by an optical reflection sensor in the present embodiment) 26 is used as a trigger for changing timing control of the switching claw for changing the transport direction at the time of paper discharge or reversal.

The paper discharge roller 16 and the single-sided paper discharge roller 5
5. The double-sided paper discharge roller 59 is controlled by the CPU 29, and is a paper discharge motor (in this embodiment, a stepping motor).
2 driven. For example, when discharging a single-sided document, the discharge switching claw 56 is switched by the reversing solenoid to the direction in which the document is transported in the direction e. In this way, the original is conveyed by the paper discharge roller 16 and the single-sided paper discharge roller 55 and discharged to the single-sided paper discharge tray 17. Also,
When the two-sided document is reversed and transported onto the contact glass 19, the paper discharge switching claw 56 is switched so that the document is transported in the f direction, and the paper discharge inversion switching claw 58 is moved in the h direction by a reverse solenoid (not shown). The document is switched so that the document is conveyed. In this state, the document is conveyed by the paper discharge roller 16, and is fed onto the contact glass 19 with the document surface inverted.

The inverted document is transferred to a single-sided paper discharge tray 1
When it is discharged to 7, the page order of the document bundle is reversed, which is inconvenient.
The reversal document is discharged onto the double-sided discharge tray 60. At this time, the paper discharge switching claw 56 is moved
The document is switched in the direction g so that the document can be conveyed, and the document is discharged onto the both-side discharge tray 60 by the two-side discharge roller 59.

The reversing sensor 26 is an optical reflection type sensor, and the discharge switching claw 5 at the time of document reversal and at the time of double-sided discharging.
6 is used as a trigger of the change timing control and as a trigger of the change timing control of the discharge reversal switching claw 58 at the time of double-sided discharge.

The single-sided paper discharge tray 17 is provided in the apparatus main body 2 so as to be detachable, and is configured to detect whether or not it is mounted on the apparatus main body 2 by the tray sensor 64.

Further, the ADF 1 is attached to the ADF 1 by lift-up means (not shown) on the side of the main body 2 such as a hinge.
It has a lift-up sensor (optical reflective sensor) 27 for detecting that 1 has been lifted up. In the present embodiment, each of the motors 30 to 33 and 35 is configured to be independently drivable.

On the other hand, the main body 2 includes an image reading section (scanner) 61, an image forming section (not shown), and the like. The scanner 61 is located in the scanner unit, and includes a mirror, a light source, an imaging lens, a shading plate, and a photoelectric conversion element (C
CD line sensor), a scanner motor, and the like. The scanner 61 irradiates the original 5 placed on the contact glass 19 with light from a light source below the contact glass 19 in the pressure plate mode or the automatic paper feed mode, and is driven by the scanner motor to sequentially move in the sub-scanning direction. The reflected light from the original 5 is imaged on a light receiving surface of a CCD line sensor via a mirror and an image forming lens on a line-by-line basis, and the image surface of the original 5 is sequentially converted into an image signal (image data).

The image forming section comprises a scanning optical system (not shown), a writing optical system such as a mirror, a photosensitive member, a developing device, a transfer device, a separating device, a fixing device, and the like. After performing image processing such as scaling processing on the obtained image signal, an image is formed by a known electrophotographic process. That is, a writing operation is performed in the writing system to form an electrostatic latent image on the photoconductor,
The toner is adhered to the electrostatic latent image, developed and visualized.
At the same time as the image forming operation, copy paper in a paper feed cassette corresponding to the size of the document is supplied, and the toner image on the photoconductor is transferred to the copy paper. The copy sheet after the transfer is separated from the photoreceptor, and is discharged after the toner image is fixed by the fixing device.

Next, the configuration of the control unit (= control means) of the copying machine of the present embodiment will be described. As shown in FIG.
The ADF 1 mounted on the main body 2 of the copying machine has a CPU 29 for controlling the operation of the ADF 1, and the CPU 29
Each sensor 15, 21, 26, 27, 50, 51, 54,
62, a detection signal from each of the motors 30 to 33, 35, a control signal (a sheet start signal, etc.) transmitted through a communication means (serial communication line) with the main body 2,
Alternatively, a cover open signal indicating that the covers 24 and 25 are open is input.

The CPU 29 controls the sensors 15, 21
In addition to transmitting information indicated by the signal from the CPU or the like to the CPU 41 of the main body 2, it controls driving of each of the motors 30 to 33 and 35 based on a control signal transmitted from the CPU 41. For example, when the document set sensor 21 detects that the document 5 has been set on the sheet feeding table 6 and the bottom plate 7, the detection information is transmitted to the CPU 41 as a document set signal by the CPU 29 via the communication unit. Or,
When the lift-up sensor 27 detects that the ADF 1 has been lifted up with the hinge as a fulcrum,
The detection information is transmitted by the CPU 29 to the CPU 41 as a lift-up signal via the communication means. The RAM 28 stores an operation mode (such as a one-sided / two-sided copy mode) input and set from the operation unit 43 of the main body 2, and updates the stored content every time the operation mode is changed. Further, the RAM 28 stores a document size in the transport direction or a document size in the width direction calculated based on the document detection information of the pull-out sensor 51 and the registration sensor 15.

On the other hand, the main body 2 of the copying machine has a CPU 41 for controlling the entire apparatus. The CPU 41 is provided with detection information signals from various sensors 44 of the main body 2 and an input / output unit (not shown drive motor). And various loads such as clutches) 45
, A variety of signals from the operation unit 43, a signal transmitted from the ADF 1 via the communication unit, or an information signal such as a document JAM or a serviceman call. The CPU 41 performs drive control of the input / output unit 45, display control of the operation unit 43, and the like based on the information indicated by the signal thus received and input.
The CPU 2 transmits a signal indicating a copy operation mode or various control signals including a paper feed start signal for starting the paper feed operation by driving and rotating the call roller 8 to the CPU 2.
9 to control the paper feeding operation of the ADF 1.

The operation unit 43 includes various button keys such as a start button and numeric keys (not shown),
It has a D display and the like, and is configured so that setting of each operation mode and operation start / stop instructions can be performed by a user operation.
Further, when the start button is pressed after the document set is detected, the CPU 41 stores the pressed information in the RAM 4.
2 in the predetermined area, and the ADF1
To send a feed start signal to the printer. By doing so, AD
In F1, the feeding roller 8 is automatically driven and rotated to start the sheet feeding operation.

Next, the operation of the ADF 1 in the automatic paper feed mode of this embodiment will be described. The user sets the document 5 such that the leading end of the document 5 in the paper feeding direction comes into contact with the document abutting member 22 and moves the side fence 81 on a rail (not shown) to regulate the width direction of the document 5. On this occasion,
The front-side pressing plate 82a and the rear-side pressing plate (not shown in FIG. 2) are set at predetermined uppermost positions. After setting the original, the user lowers the front-side pressing plate 82a and the rear-side pressing plate to set the original at the document height. To press the upper surface of the original.

When the original 5 is set on the paper feed table 6 and the start button is pressed, the bottom plate up / down motor 33 is driven to move upward with the rise of the bottom plate 7 and to move the call roller up and down. When the call motor 8 is driven by the driving motor 35, the call roller 8 comes down and is pressurized. Thereafter, the separation roller 9 and the separation roller 1 are rotated from the uppermost position of the document 5 by rotating the calling roller 8 in the sheet feeding direction.
0 is fed to the separation mechanism. The separation mechanism
The originals separated one by one are placed on a contact glass 1 by a pull-out roller 11, a transport roller 12, and a transport belt 13.
The image data is read by an optical element such as a CCD by the exposure of the exposure unit. At this time, the document is stopped at a position where the leading edge of the document abuts on the document scale 20.

In the present embodiment, information on the document length detected by the pull-out sensor 51 and the registration sensor 15 is transferred to the RAM 28 when the document is conveyed onto the contact glass 19 for reading an image and stopped. It is memorized. As a method for calculating the document length, as described above, the feed motor 30 and the transport motor 31 are constituted by the stepping motors. It is obtained for each document by multiplying the number of driving steps while the pull-out sensor 51 detects the presence of the document during paper. Regarding the determined document length, for example, if there is one document on the contact glass 19, the length of the document is stored in the first storage memory of the RAM 28.
If there are a plurality of upper documents, the length of the second document is stored in the second storage memory, the length of the third document is stored in the third storage memory, and so on. It is memorized.

In this configuration, the feed motor 30 and the transport motor 31 can be independently driven as described above, so that the original on the contact glass 19 is discharged before the next original is fed. This is because it is possible to arbitrarily change whether a plurality of originals are arranged on the contact glass 19 and how long the arranged originals are spaced. In this manner, the sheets are sequentially fed from the top document, and when the feeding of the final document is completed, the bottom plate 7 that has lifted the leading end of the document is lowered.

On the other hand, when the reading of the image has been completed and the document has arrived at the entrance of the paper discharge section 90, in the single-sided mode, it is detected by the paper discharge sensor 54, and the paper discharge roller 16 is driven to drive the single-sided paper discharge tray. It is discharged to 17. In this case, the discharge switching claw 56 is switched so that the document is transported in the direction e, and the document is transported by the discharge roller 16 and the single-side discharge roller 55 and discharged to the single-side discharge tray 17. Each time one document is discharged, the contents of the second storage memory are stored in the first storage memory and the contents of the third storage memory are stored in the second storage memory.
The document length is shifted and stored in the storage memory. Since the transport motor 31 is constituted by a stepping motor, for example, while the document is being transported to the paper discharge unit 90, the pulse of the transport motor 31 is counted, and the number of pulses per one step of the transport motor 31 is calculated. By multiplying the document feed amount, the document transport distance on the transport belt 13 can be known.

Further, the discharge sensor 54 of the discharge section 90 detects discharge JAM and discharge deceleration timing. For example, regarding the paper ejection JAM detection, the pulse of the paper ejection motor 32 after the leading edge of the original has passed the paper ejection sensor 54 is counted, and the result is multiplied by the original feed amount of the paper ejection motor 32 per step. This is performed by knowing the document conveyance distance at the paper discharge roller 16 after passing through the sensor and comparing with the document length. Therefore, the length of the document and the transport distance of the document can be accurately known without being affected by a change in the transport speed, and the criterion based on the transport distance at the time of JAM detection can be changed according to the document size.

In the case of the double-sided mode, the two-sided original after the single-sided reading is turned over and the discharge rollers 1
The sheet is conveyed to a reading position on the contact glass 19 by 6. Thus, the original is turned over and the contact glass 1
The document is then sent to a reading position on the document 9 and the back side of the document is read by the scanner 61. Here, if the inverted document after the double-sided reading is discharged to the single-sided paper output tray 17, the page order of the document bundle is reversed, which is inconvenient. Therefore, the discharge of the inverted document is performed by the double-sided paper discharging roller 59 as described above. 60.

According to the present embodiment, the side fence 81
The user can arbitrarily move the pressing plate 82a and the like up and down by the side rails 83a and 83b and the corresponding slide members 85 and the like, so that the upper surface of the document can be pressed according to the document height without obstructing the document setting. Actions can be taken. The curl habit of a stiff original can be corrected by the user operating the pressing plate to perform a pressing operation according to the height of the original. Further, according to the present embodiment, even after the document is set, the side fence 81 can be moved in the width direction to regulate the width direction of the document.
Easy to use.

[Second Embodiment] FIG. 5 shows the configuration of a paper feed table according to a second embodiment of the present invention, and FIGS. 6 and 7 (views A in FIG. 6) show the paper feed table. 3 shows a configuration of a front pressing plate of a front fence in a table. Since the overall configuration of the image forming apparatus of this embodiment is substantially the same as that of the first embodiment, FIGS. 1 and 4 will be used, and the same components will be denoted by the same reference numerals and description thereof will be omitted. .

In the present embodiment, as shown in FIG. 5, the pressing plate 8 is provided on the front side (the front fence 81a side) of the sheet feeding table 6.
2a and 82b, and a lowering switch 87 for lowering the pressing plates 82a and 82b. The user can switch these switches 86 and 87.
By pressing the front pressing plate 82a and the rear pressing plate 8
2b is configured to move up and down at the same height. By pressing the up switch 86 and the down switch 87, a signal is sent to the CPU 29 of the control unit (ADF1 side).
During the input of this signal, the CPU 29 sets the front pressing plate up / down motor 91a constituted by a stepping motor.
(Shown in FIGS. 6 and 7) and a pressing plate up / down motor (not shown) on the rear side are driven forward and reverse to rotate the pressing plates 82a and 82b.
Is raised / lowered.

The drive mechanism (= rack and pinion mechanism) of the front pressing plate 82a in the front fence 81a is as shown in FIGS. 6 and 7, and the rack 89a attached to the front pressing plate 82a and the inside of the front fence 81a. And a pinion 92a provided on a front-side pressing plate vertical motor 91a (= drive motor) is engaged with the front-side pressing plate 82a by driving the pressing plate vertical motor 91a. Although FIGS. 6 and 7 illustrate the front fence 81a and the front pressing plate 82a, the rear fence (hereinafter, referred to as a rear fence) 81b and the rear pressing plate 82b of the side fence are similar to the front fence. Having a configuration. Then, the pressing plates 82a and 82b are set at the same position (home position),
a, a pressing plate vertical motor 91a on the front side and a rear pressing plate vertical motor (not shown) for driving the 82b,
Control is performed in synchronization with the number of drive pulses based on the home position. In the present embodiment, the rack 89
a, the pinion 92a, etc. constitute the adjusting means.

Although not shown in this embodiment,
In order to detect the home position of the rear pressing plate 82b, a pressing plate sensor (in the present embodiment, constituted by an optical reflective sensor) is provided near the home position, and the end of the rear pressing plate 82b has a home position. A filler for position detection is provided. The pressing plate sensor is connected to the rear pressing plate 8.
When the filler provided at the end of 2b shields light, it detects that the rear pressing plate 82b is at the home position. The detection information of this pressure plate sensor is stored in the CP of the control unit.
U29, and the CPU 29 presses the pressing plates 82a, 82b.
To the home position. The pressing plate 82
The configuration for detecting the home position b is the same as in the third embodiment described later.

With this configuration, the user sets the document 5 such that the leading end of the document 5 in the sheet feeding direction comes into contact with the document abutting member 22, and then moves the front fence 81a to the rail 8
8, the width direction of the original 5 is regulated. After the original is set, the user keeps pressing the lowering switch 87 to drive the pressing plate up / down motors 91a and the like in both fences, and the pressing plates 82a and 82b descend from the home position and press the upper surface of the original. Thereafter, when the start button is pressed, the sheet feeding / transporting operation is started, and after the sheet passing procedure for all the originals on the sheet feeding table 6 is completed, the user presses the up switch 86 so that the CPU 29 Then, the pressing plates 82a and 82b are raised by reversely driving the pressing plate vertical motors on the rear side and the front and rear sides when the pressing plates 82a and 82b reach the home position based on the detection information of the pressing plate sensor. Of the pressing plate up / down motor is stopped.

According to this embodiment, the user can operate the ascending switch 86 and the descending switch 87 to move the pressing plates 82a and 82b up and down as desired.
The pressing operation of the upper surface of the original can be performed according to the height of the original without obstructing the setting of the original. The curl habit of a stiff original can be corrected by the user continuing to press the lowering switch 87 and performing a pressing operation according to the height of the original.

[Third Embodiment] FIG. 8 shows the position of the pressing plate when a document is not set in the third embodiment of the present invention, and FIG. 9 shows the position of the pressing plate when the document is set. . Since the overall configuration of the image forming apparatus according to the present embodiment is substantially the same as that of the second embodiment, FIG. 1, FIG. 4, FIG. 6, FIG.
And the same reference numerals are given to the same components, and the description is omitted.

As shown in FIGS. 8 and 9, in the present embodiment, a document height sensor (to detect whether the rear pressing plate 82b is set at the height of the document bundle set on the sheet feeding table 6). In this embodiment, the optical reflection type sensor is used.)
95 and the like are provided on the rear pressing plate 82b of the rear fence 81b fixedly disposed on the sheet feeding table 6. The pressing plate 82b is provided with a document height filler 98 fixedly supported by a rotatable fulcrum shaft 97 and arranged so as to slightly protrude from the lower surface of the pressing plate 82b.
An arm 99 and a sensor filler 96 are also fixedly supported by the device 7. Further, a return spring 101 is attached to the arm 99.
The other end of the return spring 101 is attached to another arm provided on the pressing plate 82b.

Therefore, the arm 99 is connected to the return spring 10
1, the original height filler 98 and the sensor filler 96 are urged to rotate clockwise, so that the original height filler 9 of the pressing plate 82b is rotated.
The fulcrum shaft 97 is configured not to rotate counterclockwise even if the curl document 8 contacts the original.

When the original height filler 98 contacts the upper surface of the original bundle, the original height filler 98 rotates about the fulcrum shaft 97, and the sensor filler 96 also rotates about the fulcrum shaft 97. When the sensor filler 96 is displaced from the light shielding position of the document height sensor 95, the document height sensor 95 detects that the pressing plate 82b has descended to the upper surface of the document bundle.

In this embodiment, a pressing plate sensor (in the present embodiment, constituted by an optical reflection sensor) 93 is provided near the home position of the rear pressing plate 82b in order to detect the home position of the rear pressing plate 82b. A configuration is such that a filler 94 provided at the end of the rear pressing plate 82b shields the pressing plate sensor 93 from light, thereby detecting that the rear pressing plate 82b is at the home position.

The detection signals from the document height sensor 95 and the pressing plate sensor 93 are sent to the CPU 29 of the ADF1 side control unit, and based on these signals, the CPU 29 controls the front and rear pressing plate vertical motors 91a, 91b is driven and controlled. In the present embodiment, a document height sensor 95, a document height filler 98, a fulcrum shaft 97, a sensor filler 96, an arm 9
The return spring 101 and the like constitute a document height detecting means, and the pressing plate sensor 93, the filler 94 and the like constitute a home position detecting means.

Next, the operation of the pressing plates 82a and 82b in this embodiment will be described with reference to FIG. In step 1001, when the user presses the start button after setting the document bundle on the sheet feeding table 6, the CPU
29 is a front and rear pressing plate vertical motor 91a, 91
b is driven forward.

In step 1002, the pinion 92a, 92b is driven by the forward rotation of the pressing plate up / down motors 91a, 91b.
b rotates forward, and the racks 89a, 89b meshing with the pinions 92a, 92b descend, whereby the pressing plate 8
2a and 82b start descending from the home position (position A).

In step 1003, the document height sensor 9
5 is ON, that is, as described above, the document height sensor 9
The CPU 29 determines whether or not the pressing plate 82b is in contact with the upper surface of the document bundle by checking whether the sensor plate 5 is shielded from light by the sensor filler 96 provided on the rear pressing plate 82b (OFF / ON). As a result, if the rear pressing plate 82b is not in contact with the upper surface of the document bundle, the process returns to step 1002 to continue the forward rotation driving of the pressing plate vertical motors 91a and 91b.
If the pressing plate 82b is in contact with the upper surface of the document bundle, the process proceeds to step 1004.

In step 1004, the CPU 29 stops driving the pressing plate up / down motors 91a and 91b and stops lowering the pressing plates 82a and 82b. This is the pressing plate 8
By stopping 2a and 82b at the document height position (upper surface of the document bundle), even if there is a curled document, it is surely pressed,
This is because the original is normally fed.

In step 1005, the CPU 29 starts the reverse driving of the pressing plate up / down motors 91a and 91b. This is because when the sheet feeding operation is started in a state where the pressing plates 82a and 82b press the upper surface of the document bundle, the pressing plate itself becomes a sheet feeding resistance, and the pressing plates 82a and 82b are raised by a predetermined amount from this state. .

In step 1006, the pressing plates 82a, 82b are raised by 1 mm by driving the pressing plate up / down motors 91a, 91b in reverse rotation by a predetermined number of pulses.

In step 1007, the pressing plates 82a and 82b are raised by 1 mm as described above, and then the driving of the pressing plate vertical motors 91a and 91b is stopped.
The descent of 82b is stopped.

In step 1008, the CPU 29 drives the paper feed motor 30 to start the paper feed operation.

In step 1009, the CPU 29 drives the pressing plate up / down motors 91a and 91b to rotate forward in accordance with the number of sheets fed, and controls the interval between the upper surface of the original bundle and the pressing plates 82a and 82b to be constant. This is because a smooth paper feeding operation is performed by adjusting the distance between the upper surface of the document bundle and the pressing plates 82a and 82b to a reduction in the height of the document bundle accompanying the progress of the paper feeding operation.

In step 1010, the CPU 29 determines whether reading of the original set on the paper feed table 6 has been completed based on the detection signal (original end signal) from the original set sensor 21. As a result, if all the readings have not been completed, the flow returns to step 1009 and the pressing plate up / down motor 91 according to the number of sheets fed together with the sheet feeding operation.
The forward rotation drive of steps a and 91b is continued, and when reading is completed, the process proceeds to step 1011.

In step 1011, the CPU 29 starts the reverse rotation driving of the pressing plate up / down motors 91 a and 91 b.

In step 1012, the pressing plates 81a, 91b are driven by the reverse rotation of the pressing plate vertical motors 91a, 91b.
82b rises to the home position.

In step 1013, the CPU 29 determines whether or not the pressing plates 82a and 82b have reached the home position, based on whether or not the filler 94 blocks the pressing plate sensor 93 (OFF / ON) as described above. As a result, if the pressing plates 82a and 82b have not reached the home position, the process returns to step 1012 to return to the pressing plate vertical motor 9
1a and 91b continue to be driven in reverse rotation, and the pressing plates 82a and 82b
If b has reached the home position, step 101
Proceed to 4.

In step 1014, the CPU 29 stops driving the pressing plate vertical motors 91a and 91b, and
2a and 82b are stopped at the home position.

According to the present embodiment, since the pressing plates 82a and 82b of the side fence 81 come into contact with each other and press the upper surface of the document bundle in accordance with the height of the document bundle, the curled document can also be reliably pressed. Accordingly, it is possible to prevent the fed document from being skewed, and to improve the transport quality of the document. Further, according to the present embodiment, after the pressing plates 82a and 82b of the side fence 81 descend and press the upper surface of the document bundle in accordance with the height of the document bundle, the pressing plates 82a and 82b are raised by a predetermined amount, and Since an appropriate distance is maintained between the upper surface of the bundle and the pressing plate, the pressing plate does not give a feeding resistance to the fed document, and skew due to the pressing plate itself can be prevented.

[0076]

According to the first, second and sixth aspects of the present invention,
The pressing means (= pressing plate) for pressing the upper surface of the document stored in the storing means (= feeding table) by the user's operation, and the adjusting means (= drive motor, rack and pinion mechanism, etc.) move up and down. This allows the height of the pressing means to be adjusted arbitrarily and presses the upper surface of the document, so that curling can be performed without generating sheet feeding resistance in accordance with the number (height) of stacked documents set in the storage means. While holding down the manuscript,
It is possible to prevent a skew from occurring when the document exceeds the width direction regulating means (side fence) at the time of paper feeding.

According to the third, fourth, fifth and sixth aspects of the invention, the amount of movement of the pressing means by the adjusting means is controlled based on the detection information of the document height detecting means (= document height sensor, etc.). Therefore, the curl document can be held down without causing a sheet feeding resistance according to the number of loaded documents set in the storage means regardless of the user's operation, and the document can be skewed beyond the width direction regulating means during paper feeding. Can be prevented from occurring.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an automatic document feeder mounted on a copying machine main body according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a front fence end of a side fence of the copying machine according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a shape of a pressing plate of a side fence of a copying machine according to another embodiment of the present invention.

FIG. 4 is a diagram illustrating a configuration of a control unit of the copying machine according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a configuration of a main part of a sheet feeding table of a copying machine according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a configuration of a front fence end of a side fence of a copying machine according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of FIG. 6 as viewed from a direction A.

FIG. 8 is a diagram showing a configuration of a rear fence end of a side fence in a copying machine according to a third embodiment of the present invention.

FIG. 9 is a diagram showing a configuration of a rear fence end of a side fence in a copying machine according to a third embodiment of the present invention.

FIG. 10 is a flowchart illustrating an operation of a pressing plate when a copying machine feeds paper according to a third embodiment of the present invention.

FIG. 11 is a diagram showing a configuration of a main part of a paper feed table in a conventional automatic document feeder.

FIG. 12 is a cross-sectional view of FIG. 11 viewed from the direction A.

[Explanation of symbols]

Reference Signs List 1 automatic document feeder 2 image forming device 5 document 6, 71 paper feed table 21 document set sensor 29, 41 CPU 43 operation unit 75a, 75b, 81, 81a, 81b side fence 77a, 77b pressing member 82a, 82b, 82c, 82d, 82e, 82f Pressing plate 86 Up switch 87 Down switch 89a, 89b Rack 91a, 91b Pressing plate up / down motor 92a, 92b Pinion 93 Pressing plate sensor 95 Original height sensor

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H076 BA15 BA22 BA41 BA48 BA62 EA14 3F343 FA03 FB02 FC12 GA02 GB02 GC01 GD01 HA12 HA33 HB01 HD07 HD08 HD09 HE04 HE17 HE20 HE23 LA04 LA14 LC07 LD10 LD22 MA04 MA09 MA32

Claims (6)

[Claims] An accommodating means for accommodating a plurality of documents in a stacked state; a width direction regulating means provided in the accommodating means for regulating a width direction of the documents accommodated in the accommodating means; Pressing means provided on the means and pressing the upper surface of the document stored in the storing means, and adjusting means for arbitrarily adjusting the height position of the pressing means by moving the pressing means vertically. An automatic document feeder, wherein the upper surface of the document is pressed in accordance with the stacking height of the document stored in the storage means. 2. The automatic document feeder according to claim 1, wherein said adjusting means moves the pressing means in a vertical direction based on input information input by a switch operation. 3. An original height detecting means for detecting whether or not a pressing means is provided at a stacking height of the originals stored in the storing means, and the adjusting means based on detection information of the original height detecting means, wherein the adjusting means comprises a pressing means. 2. The automatic document feeder according to claim 1, further comprising control means for controlling a moving amount of moving the document in a vertical direction. 4. The control means according to claim 1, wherein the control means lowers the pressing means to contact the upper surface of the document based on the detection information of the document height detecting means, and then raises the pressing means by a predetermined amount to make the pressing means contact the upper surface of the document. 4. The automatic document feeder according to claim 3, wherein a distance from the means is maintained. 5. A home position detecting means for detecting whether the pressing means is at the home position, and a control means for raising the pressing means to the home position when the feeding operation of all the originals stored in the storing means is completed. The automatic document feeder according to claim 4, further comprising: 6. The adjusting means includes a drive motor for driving the pressing plate in a vertical direction, and a rack and pinion mechanism for converting a rotational force of the driving motor into a vertical movement of the pressing plate. 6. The automatic document feeder according to claim 1, wherein: