JP2004269256A - Sheet material feeder, image reader, image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet feeder, automatically detecting the lowering state of the transport force due to adhesion of oil, decreasing the transport speed to lower the document return force of a reverse roller, and heightening the follow-up performance between a roller or a belt and a document. <P>SOLUTION: When the transport and separating performance of a pickup roller 7 and a paper feed belt 9 are remarkably lowered to cause slip of a document, the rotating speed of the pickup roller 7 is decreased. Whereupon, the transport performance is heightened so that the copy operation is continued even in the status of stopping the copying operation as a non-feed jam in the past. The pulses of a pulse motor for driving the pickup roller 7 are counted to detect a change in the speed of the pickup roller 7, whereby a simple determination condition can be used as a threshold even in the case where the arrival time of the leading edge of the document to a contact sensor 11 is not uniform. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a sheet material supply device and an image reading and feeding device used for an image forming apparatus such as a copying machine and a facsimile. More specifically, the present invention relates to a sheet material supply device that conveys a sheet material and supplies it to an image forming unit of an image forming apparatus, and an image reading device that supplies a sheet document to an image reading unit of the image forming device. Further, the present invention relates to an image forming apparatus using such a sheet material supply device or an image reading device.

  2. Description of the Related Art There are various types of paper feeders for supplying transfer paper to an image forming unit of an image forming apparatus such as a copying machine, and a document feeder for feeding a document from which an image is to be read. Of these, the type that has become popular today is the FRR paper feed system. In this method, one sheet of the sheet material stacked on the separation set portion is called by a calling means such as a calling roller called a pickup roller, and this is called by a feed belt and a reverse roller arranged downstream in the sheet material conveying direction. These are separated and transported one by one. At present, this method is common.

  In a conventional document feeder of this type, the front side of a document is set upward. That is, the image is set on the document stacking section so that the image surface can be seen by the user. Then, the original is turned upside down while the separated original is conveyed in the apparatus. When the document arrives at the reading unit (exposure unit) of the image forming apparatus, the image surface of the document set upward can be read from below. The original whose image has been read is discharged as it is. The surface of the discharged document faces downward. Therefore, by sequentially placing the originals to be discharged on the upper side, the reading of a plurality of originals is completed without changing the page order.

  By the way, in recent years, in particular, in a document conveying apparatus for conveying a document to an exposure unit, there is a problem of responding to diversification of a used document. For example, there is an increasing need to use a copy sheet output as a color copy as a document and copy the image. However, many color copy originals have a surface coated with silicone oil, and the oil adheres to a pickup roller or a paper feed belt, so that the conveying force of the original decreases as the number of sheets passed increases. In some cases, problems such as non-feeding and paper jam (jam) may occur.

  That is, as described above, when the document is set with the front side facing upward and fed, as long as the silicone oil does not adhere to both sides of the document, the adhesion of the silicone oil occurs on the feed belt (separation belt) and the pickup roller, It does not occur on the reverse roller. For this reason, the balance between the document returning force by the reverse roller and the conveying force by the paper feeding belt is out of order. This is because, while the conveyance force by the paper feed belt decreases, the return force of the reverse roller does not change much, and the slip ratio of the document increases.

  There is known an apparatus configuration in which the pickup roller and the separation belt are rotated by the forward rotation of the drive motor, and the pull-out roller is rotated by the reverse rotation of the same drive motor, thereby reducing the size. This apparatus has a mechanism for correcting skew. This mechanism transports the original more than the required length during the forward rotation of the drive motor when separating and transporting the original, and abuts the leading end of the original against the stopped pull-out roller, making the leading end of the original perpendicular to the transport direction. Align to make it. In this mechanism, a sensor (abutting sensor) disposed immediately before a document is abutted against a pull-out roller is used to set a transport path (a transport distance on a machine layout) and a transport amount for abutting the document. It is supposed to do.

  In addition, a technique for maintaining the copy speed at a predetermined amount, which does not improve the document conveyance performance, has also been proposed. In this mechanism, the pickup roller is brought into contact with the sheet material, the pickup roller is rotated according to the movement of the sheet material, and the rotation is detected by an encoder attached to the rotating shaft, and the difference in the feeding amount of the sheet material is detected. If there is, the rotation speed of the pickup roller (constant speed determined at the start of rotation) and the rotation start timing are controlled (for example, see Patent Document 1).

  Further, a technique has been proposed in which the rotation continuation time of the pickup roller is extended according to the extent that the conveyance distance of the document when the pickup roller is rotated for a predetermined time is less than a predetermined distance (for example, see Patent Document 1). 2). The jam is prevented by making the actual transport distance of the original by the pickup roller substantially equal to a predetermined distance.

JP-A-10-101238 JP-A-6-271149

  However, aging of the pickup roller, in particular, reduction in the frictional force between the pickup roller and an original made of paper or the like due to contamination, adhesion of paper dust, oil, or the like is not considered in the above-described conventional technology. Attention must also be paid to the frictional force between the originals when processing a plurality of originals, the electrostatic attraction between the originals, their changes, and the like. This causes a reduction in the conveying force in the FRR sheet feeding method, and causes a non-sheet feeding in which the document is not properly fed.

  In the technique of Patent Document 1, no consideration is given to slippage when passing a color original or the like to which oil has adhered. For this reason, the transport amount of the document may be less than the required amount, and the leading edge of the document may not hit the pull-out roller, and non-feeding may occur.

  Of course, oil-less color copiers are being developed, but many color copiers currently on the market are still oil-treated. As described above, the above problem is likely to occur when a color image is transferred to the front side of a document.

  Further, in the technique of Patent Document 2, when an original that easily slips is used, the rotation time of the pickup roller increases while the original is slipping, so that the original is damaged by a pencil-written original or thin paper.

  Therefore, the present invention has a function of automatically detecting a state in which the conveyance force is reduced due to oil adhesion or the like, reducing the document return force by lowering the conveyance speed, and using a conveyance device such as a roller or a belt to transfer the document. It is an object of the present invention to provide a sheet supply apparatus, an image reading apparatus, and an image forming apparatus using the same for feeding a document or a sheet, which can increase the followability between sheets and reduce the rate of non-feeding.

  The sheet material supply device according to the first aspect of the present invention is configured to rotate the sheet material while being in contact with the stacked sheet materials, and to feed the sheet material, and by rotatingly contacting the fed sheet material. A separating mechanism for separating the overlapped and fed sheet material into one sheet, comprising a rotating member for feeding the sheet material and a blocking means for preventing conveyance of the overlapped and fed sheet material; and the feeding means and / or the rotation. Driving means for driving the member, sheet material detecting means for detecting the leading end of the sheet material, driving amount detecting means for detecting the driving amount of the driving means, and a detection result of the sheet material leading end by the sheet material detecting means. And a control means for variably controlling the rotation speed of the feed-out means and / or the rotating member.

According to a second aspect of the present invention, in the sheet material supply apparatus according to the first aspect, the control unit temporarily changes the rotation speed of the feeding unit and / or the rotating member, and thereafter, the sheet detection unit changes the rotation speed of the sheet material. When the leading end is not detected and the driving amount of the driving means does not reach the predetermined driving amount, the control means changes the rotation speed of the feeding means and / or the rotating member again.

  According to a third aspect of the present invention, in the sheet material feeding apparatus according to any one of the first and second aspects, the control means has a plurality of threshold values for changing a rotation speed of the feeding means and / or the rotating member. Features.

  According to a fourth aspect of the present invention, in the sheet material supply device according to any one of the first to third aspects, it is preferable that at least one of the sheet material detection units is arranged downstream of the separation mechanism in a sheet conveying direction. , At least one unit is disposed on a transport path between the separation mechanism and the feeding unit.

  According to a fifth aspect of the present invention, in the sheet material supply device of the fourth aspect, at least one sheet material detecting unit is disposed on a transport path between the separation mechanism and the feeding unit.

  According to a sixth aspect of the present invention, in the sheet supply apparatus according to any one of the first to fifth aspects, a display unit capable of displaying an operation state is provided, and the sheet detection unit is configured to switch the separation mechanism in a sheet conveying direction. Downstream, and disposed on the transport path between the separation mechanism and the feeding means, and when the slip amount at the feeding means exceeds a predetermined slip amount, the control means displays the display means with the display means. Displaying information prompting replacement of the feeding means, and when the slip amount in the separation mechanism exceeds a predetermined slip amount, the control means displays information prompting replacement of the rotating member on the display means. It is characterized by.

  According to a seventh aspect of the present invention, in the sheet material feeding apparatus of the sixth aspect, when the slip amount continuously exceeds a predetermined slip amount, the information is displayed on the display means.

According to an eighth aspect of the present invention, in the sheet material supply device according to the first to seventh aspects, the driving amount detecting unit detects a driving time of the driving unit.

  According to a ninth aspect of the present invention, in the sheet feeding apparatus according to any one of the first to eighth aspects, the driving means for driving the feeding means is a pulse motor, and the driving amount detecting means is configured to determine the number of pulses of the pulse motor. Is detected.

  According to a tenth aspect, in the sheet feeding apparatus according to any one of the first to ninth aspects, the feeding means is a pickup roller.

  An image reading apparatus according to an eleventh aspect is characterized in that a sheet original is fed using the sheet material supply apparatus according to any one of the first to tenth aspects.

  An image forming apparatus according to a twelfth aspect is characterized in that a sheet document is fed using the image reading apparatus according to the eleventh aspect.

  According to the present invention, the conveyance force in the feeding means for feeding out the sheet material and the separation mechanism for separating the sheet material into one sheet is significantly reduced, and the slip of the document occurs, so that the sheet cannot be conventionally fed. In a situation where the operation of the apparatus has to be interrupted, the operation can be continued by lowering the rotation speed of the feeding means.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to an embodiment shown in the drawings. The embodiment described below relates to an automatic document feeder (hereinafter, referred to as an ADF) used in a device that conveys a document to be read to a fixed reading device and reads an image while conveying the document at a predetermined speed. However, it is needless to say that the present invention is not limited to this example and can be applied to various sheet material supply devices. Further, the image forming apparatus including the sheet material supply device or the image reading device according to the present invention is not limited to the illustrated example.

  FIG. 1 is a sectional view conceptually showing an image forming apparatus such as an electrophotographic copying machine or a printer according to the present invention. The image forming apparatus of the present embodiment mainly includes a reading unit 600 for reading a document, an image forming unit 610 for forming an image, an automatic document feeder (ADF) 620, a document discharge tray 630 for stacking documents sent from the ADF 620, The paper feed unit 680 includes paper feed cassettes 640 to 670 and a paper discharge unit 690 for stacking recording paper.

  Inside the image forming unit 610, a photoconductor 611 as an image carrier is arranged. The photoconductor 611 is driven to rotate clockwise in the drawing, and the surface is charged to a predetermined potential by the charging device 612. Further, the writing unit 613 irradiates a laser beam L light-modulated according to image information read by the reading unit 600, and exposes the surface of the charged photoconductor 611 with the laser beam L. An electrostatic latent image is formed on the surface of 611. After the electrostatic latent image is developed by the developing device 614, it is transferred to the recording medium P fed between the photoconductor 611 and the transfer device 615 by the transfer device 615 facing the electrostatic latent image. The surface of the photoconductor 611 after the transfer of the toner image is cleaned by the cleaning device 616.

  The plurality of paper cassettes 640 to 670 arranged below the image forming unit 610 accommodate recording media P such as paper or a bundle thereof, and send out the recording media P from any of the paper cassettes 640 to 670. Then, the toner image formed on the surface of the photoconductor 611 as described above is transferred to the surface of the recording medium P. Next, the recording medium P is passed through a fixing device 617 in the image forming unit 610 to fix the toner image transferred to the surface of the recording medium P by the action of heat and pressure. The recording medium P that has passed through the fixing device 617 is conveyed by a discharge roller pair 618, discharged to a discharge tray 690, and stacked.

  FIG. 2 is a cross-sectional view illustrating a basic configuration of the ADF according to one embodiment of the present invention. 3 is a perspective view showing a paper feed drive system, FIG. 4 is a read / conveyance drive system, FIG. 5 is a lower reversing section drive system, FIG. 6 is a paper ejection drive system, and FIG. 7 is a perspective view showing an upper reversal section drive system. FIG. 8 is an electrical block diagram.

  The ADF includes a document setting unit A for setting a bundle of documents 1 to be read, a separation feeding unit B for separating and feeding the documents 1 one by one from the set document bundle, and The registration section C, which functions to first abut against and align the surface of the original 1 and pulls out and transports the aligned original 1, turns the transported original 1, and transports the original surface toward the reading side (downward). A document feeder E for reading an image of the original 1 from below the slit glass; a switchback unit F for reversing the front and back of the original 1 after reading; and a switchback unit F for switching back. An intermediate transport unit G for returning the original 1 to the registration unit C again, a switchback unit H for temporarily holding the original 1 after reading the back surface, and a switchback unit H for inverting the original 1 and discharging the original 1 out of the machine. And a stack unit J for stacking and holding the original 1 after reading, and as shown in FIG. 8, a driving unit for driving these transport operations, and controlling a series of operations. It has a controller unit to perform. Note that the switchback unit F, the intermediate transport unit G, the switchback unit H, and the reversing paper discharge unit I are used when reading images on both sides of the original 1.

  One bundle of originals to be read is set on the original table 2 including the movable original table 3 with the original surface facing upward. Further, the width direction of the bundle of documents 1 is positioned by a side guide (not shown) in a direction perpendicular to the transport direction. The bundle of originals 1 is detected by the set filler 4 and the set sensor 5 and transmitted to the main body control unit 212 through an interface (I / F: not shown; the same applies hereinafter). Further, the first document length sensor 34 and the second document length sensor 35 provided on the document table surface for detecting the document length determine the approximate length of the document 1 in the transport direction. As the sensors 34 and 35, it is preferable to use a reflection type sensor or an actuator type sensor capable of detecting even one document. Therefore, it is necessary to provide a sensor arrangement that can determine at least whether the document is the same size vertically or horizontally.

  The movable document table 3 can be moved up and down in the directions of arrows a and b in FIG. 2 by a bottom plate raising motor 105 not shown in FIG. When the set filler 4 and the set sensor 5 detect that the document 1 has been set, the bottom plate raising motor 105 is rotated forward to raise the movable document table 3 so that the uppermost surface of the document bundle contacts the pickup roller 7. The pickup roller 7 is operated by a cam mechanism by a pickup motor 101 also not shown in FIG. 2 in the directions of arrows c and d shown in the figure. When the movable table 3 moves up, the pickup roller 7 is pushed by the upper surface of the original on the movable table 3 and moves up in the direction of arrow c. The table lift detection sensor 8 can detect the upper limit position of the pickup roller 7.

  When a print key is pressed from a main body operation unit 211 (see FIG. 8) of the image forming apparatus main body 200 and a document feed signal is transmitted from the main body control unit 212 to the ADF controller 100 via the I / F, a pickup is performed. The roller 7 is driven to rotate by the normal rotation of the paper feed motor 102 shown in FIG. 3, and picks up several (ideally one) originals 1 on the original table 2. The rotation direction of the pickup roller 7 is the direction in which the uppermost document is conveyed to the paper feed port, and is the left direction in FIG.

  The paper feeding belt 9 is driven in the paper feeding direction by the forward rotation of the paper feeding motor 102, and the reverse roller 10 is driven to rotate in the direction opposite to the paper feeding by the normal rotation of the paper feeding motor 102, and the uppermost document and its lower part are driven. , And only the top document is fed out and fed. Specifically, the reverse roller 10 comes into contact with the paper feed belt 9 directly or at a predetermined pressure with the document 1 interposed therebetween. When the reverse roller 10 is in direct contact with the paper feeding belt 9 or in a state of being in contact with one document, it rotates counterclockwise as the paper feeding belt 9 rotates. When two or more originals enter between the paper feed belt 9 and the reverse roller 10, the above-described co-rotating force is set to be lower than the torque of the torque limiter. Therefore, the reverse roller 10 rotates clockwise, which is the original driving direction, and functions to push back an unnecessary document, thereby preventing a double feed in which two or more documents are fed and conveyed. In the following description, this portion will be referred to as a separating portion as necessary.

  The document 1 separated into one sheet by the action of the paper feed belt 9 and the reverse roller 10 is further conveyed by the paper feed belt 9, the leading end is detected by the abutting sensor 11, and the pull-out roller is further advanced and stopped. Hits 12 Thereafter, the document 1 is fed by a predetermined distance determined from the detection of the butting sensor 11, and is eventually pressed against the pull-out roller 12, causing the document 1 to bend by a predetermined amount. By stopping the paper feed motor 102 in this state, the driving of the paper feed belt 9 is stopped. At this time, the pickup roller 101 is retracted from the upper surface of the document 1 by rotating the pickup motor 101, and the document 1 is fed only by the conveyance force of the paper feed belt 9. As a result, the leading end of the original 1 constitutes the pull-out roller 12 and enters the nip of the lower pair of rollers, whereby the leading end is aligned (skew correction).

  The pull-out roller 12 has a skew correction function as described above, and is a roller for transporting the skew-corrected document after separation to the turn roller 14, and is driven by the reverse rotation of the paper feed motor 102. When the paper feed motor 102 rotates in the reverse direction, the pull-out roller 12 and the turn roller 14 are also driven, but the pickup roller 7 and the paper feed belt 9 are not driven.

  In the figure, reference numeral 13 denotes a document width sensor. A plurality of document width sensors 13 are arranged in the depth direction (the direction perpendicular to the paper surface of the drawing), and detect the size of the document 1 conveyed by the pull-out roller 12 in the width direction orthogonal to the conveyance direction. The length of the original 1 in the transport direction is read by the abutting sensor 11 at the leading end and the trailing end of the original 1, the number of motor pulses during these readings is counted, and the count value is converted to obtain the length of the original 1. Is detected. When the original 1 is conveyed from the registration section C to the turn section D by driving the pull-out roller 12 and the turn roller 14, the conveyance speed in the registration section C is set to be higher than the conveyance speed in the reading conveyance section E. The processing time for sending the original 1 to the reading unit can be reduced. The use of the number of motor pulses to detect the feeding amount of the original 1 is merely an example. If the driving means is different, the feeding amount of the document 1 may be detected by counting other appropriate operating amounts.

  When the leading edge of the document is detected by the reading entrance sensor 15, before the leading edge of the document 1 enters the nip of the pair of upper and lower rollers constituting the reading entrance roller 16, the document transport speed is read and is read at the same speed as the transport speed. Start deceleration in order to At the same time, the reading motor 103 is driven to rotate forward to drive the reading entrance roller 16, the reading roller 19, and the reading exit roller 21. 4, when the reading motor 103 rotates, the driving force is transmitted to the pulley 321 and the pulley 322, and the driving force transmitted from the pulley 322 to the pulley 324 is transmitted to the reading exit roller 21 and the reading entrance roller 16 respectively. , And the driving force transmitted to the pulleys 324 and 325 causes the reading roller 19 to rotate.

  When the registration sensor 17 detects the leading edge of the document 1, the main controller 212 is notified of the effective image in the sub-scanning direction on the image surface at the timing when the leading edge of the document 1 reaches the reading unit 201 (determined by the pulse count of the reading motor 103). A gate signal indicating the area is transmitted until the trailing edge of the document passes through the reading unit 201. When reading one side of the document 1, the lower reversing switching claw 23 and the double-side switching claw 30 are at positions indicated by solid lines, and the document that has passed the reading and transporting unit E is transported to the stack unit J. At this time, when the leading edge of the document 1 is detected by the paper discharge sensor 22, the paper discharge motor 104 is driven to rotate forward to rotate the paper discharge roller 28 in a counterclockwise direction. Immediately before the trailing edge of the document exits the nip of the pair of upper and lower rollers of the delivery roller 28 (determined by the pulse count of the delivery motor 104 from the detection of the trailing edge of the document 1 by the delivery sensor 22), The drive speed of the motor. This is for controlling the discharged document 1 so as not to fly out of the discharge tray 29. As shown in FIG. 6, when the discharge motor 104 rotates, a driving force is transmitted to the pulleys 341 and 343, and the discharge roller 28 is rotated.

  Here, the advance operation of the next original 1 when reading one side of the original 1 will be described. When the abutting sensor 11 detects the rear end of the original 1, the paper feeding motor 102 is stopped once at the timing when the rear end of the original 1 has passed through the pull-out roller 12 (detected by the pulse count of the paper feeding motor 102), and then again It is driven to rotate in the forward direction. With this operation, the feeding operation of the next original 1 is started. At this time, the drive of the turn roller 14 is stopped, but since the one-way clutch is incorporated in the timing pulley 313, the turn roller 14 rotates continuously. The next original 1 fed is awaited in a state where the original 1 is abutted against the pull-out roller 12. When the preceding original 1 reaches a certain position (in this example, the rear end of the original 1 passes through the reading entrance sensor 15 and is located near the reading entrance roller 16), the paper feed motor 102 is driven to rotate in the reverse direction. The next original 1 is conveyed from the pull-out roller 12.

  FIG. 9 is a diagram showing a drive system showing the operation of a plurality of sheets of a two-sided original. With reference to FIG. 9, a case where a document whose both sides are to be read will be described. The process up to reading the first side (front side) of the document 1 is the same as when reading the document on one side only. However, the advance operation of the next original is not performed during the reading operation of the first side, and the next original 1 is on the original table 2 (FIG. 9A). When the leading edge of the document 1 passes through the registration sensor 17, the double-sided switching claw 30 is turned on by a solenoid (SOL in the figure, the same applies hereinafter) 112 for driving the double-sided switching claw, so that the arrow i → j direction in FIG. Go to Then, the first surface of the document 1 is read by the reading unit 201 of the reading / transporting unit E, and is guided from the lower inversion switching claw 23 to the switchback unit F through the discharge roller 28 and the upper portion of the both-side switching claw 30 (FIG. 9). (B, C)).

  At the timing when the leading edge of the document passes the paper discharge sensor 22, the paper discharge motor 104 is driven to rotate forward, and the paper discharge roller 28 is rotated counterclockwise, and at the same time, the upper reversing motor 107 is driven to rotate forward. The upper reversing roller 31 is also rotated counterclockwise. When the trailing end of the document is detected by the paper ejection sensor 22, the speed of the paper ejection motor 104 and the upper reversing motor 107 is increased so as to be higher than the reading conveyance speed, and the reading motor 103 stops. After the paper discharge sensor 22 detects the rear end of the document, the SOL 112 for the double-side switching claw is turned off at the timing when the rear end of the document 1 passes through the paper discharge roller 28 (determined by the pulse count of the paper discharge motor 104). The double-sided switching claw 30 returns in the direction of arrow j → i in FIG. Next, when the upper reversing sensor 32 detects the trailing end of the document 1, the upper reversing motor 107 is switched from normal rotation driving to reverse rotation driving, whereby the rotation direction of the upper reversing roller 31 changes from counterclockwise to clockwise, As a result, the switchback operation of the document 1 is started (FIG. 9D). As shown in FIG. 7, when the upper reversing motor 107 rotates, the driving force is transmitted to the pulleys 347 and 348 to rotate the upper reversing roller 31.

  By driving the paper feed motor 102 in the reverse direction at this timing, the relay roller 33, the pull-out roller 12, and the turn roller 14 rotate in the feed direction. The original 1 is sent again to the registration section C and the turn section D via the intermediate conveyance section G, and when the reading entrance sensor 15 detects the leading end of the original 1, the original 1 projects into the reading entrance roller 16 which is stopped with a predetermined bending. And the paper feed motor 102 stops once. The amount of deflection of the original 1 is determined according to the pulse count of the paper feed motor 102. Thus, alignment (skew correction) of the leading edge when reading the second surface of the document 1 is performed (FIG. 9E).

  Then, the sheet feeding motor 102 is again driven to rotate in the reverse direction, and the reading motor 103 is driven to rotate in the normal direction, so that the original 1 is sent to the reading and conveying section E. When the registration sensor 17 detects the leading end of the original 1, the lower inversion switching (not shown) is performed. When the nail SOL 110 is turned on, the lower inversion switching claw 23 moves in the direction of arrow f → e in FIG.

  Next, reading of the second side of the document is started by the reading unit 201, and when the paper discharge sensor 22 detects the leading end of the document 1, the lower reversing roller 106 drives the lower reversing motor 106 forward to rotate the lower reversing roller 25 counterclockwise. The document 1 passes through the lower portion of the lower reversing switching claw 23 and is guided to the switchback portion H (FIG. 9F). When the paper discharge sensor 22 detects the trailing end of the original 1 on which the reading of the second side is completed, the SOL 110 for the lower inversion switching claw is turned OFF in accordance with the pulse count of the lower inversion motor 106, whereby the lower inversion switching is performed. The claw 23 is caused to return to the direction indicated by the arrow e → f in FIG. 1 and the lower reversing motor 106 is stopped to hold the rear end of the document on the lower reversing roller 25 and enter a standby state (FIG. 9G). . As shown in FIG. 5, when the lower reversing motor 106 rotates, the drive is transmitted to the pulleys 344, 345, and 346 to rotate the lower reversing roller 25 and the auxiliary roller 27.

  Next, the advance operation at the time of double-sided reading will be described. When the upper reversing sensor 32 detects the trailing edge of the original when the original on which the reading of the first side has been completed is transported from the switchback F to the intermediate transport unit G, the timing at which the trailing edge of the original has passed through the pull-out roller 12 (feeding (Determined by the pulse count of the motor 102), the rotation direction of the paper feeding motor 102 is switched from the reverse rotation driving to the normal rotation direction, thereby starting the feeding of the next original 1. Thereafter, the operation is performed at the same timing as in the case of single-sided reading. The leading edge of the next original 1 is aligned by the pull-out roller 12 of the registration unit C (FIG. 9F), and is sent to the reading / conveying unit E from the turn unit D. When the registration sensor 17 detects the leading edge of the next original 1, the double-sided switching claw 30 moves from arrow i to arrow j in FIG. The next original 1 passes through the upper portion of the reading output roller 21 and the lower inversion switching claw 23 while passing through the first surface while being read by the reading section 201, passes through the discharge roller 28 and the upper portion of the both-side switching claw 30, and enters the switchback section F. The sheet is conveyed (FIG. 9 (H)), and the double-sided switching claw 30 returns to the direction from arrow j to i (FIG. 9 (I)). Thereafter, reading of the second side of the next original 1 is performed in the same process as described above.

  By performing such an operation, the reading of the first and second surfaces is completed, and the next document 1 is overtaken by the switchback unit H in the standby state. By turning on the SOL 111 for the lower inverted discharge switching claw (not shown) at the timing when the double-sided switching claw 30 returns in the direction of arrow j → i, the lower inverted discharge switching claw 24 is moved in the direction of arrow h → g in FIG. Move. By driving the lower reversing motor 106 in the reverse direction, the lower reversing roller 25 and the auxiliary roller 27 rotate clockwise, and the original 1 is conveyed from the reversing discharge unit I to the stack unit J. By turning off the SOL 111 for the lower inverted discharge switching claw at the timing when the leading edge of the original document is held by the discharge roller 28 (determined by the pulse count of the lower reverse motor 106), the lower inverted discharge switching claw 24 is turned to the arrow g → Return to h direction. The auxiliary roller 27 is provided in order to reduce the load caused by winding the document around the inner guide plate (not shown).

  Next, when the trailing edge of the document 1 is detected by the lower reversing sensor 26, the timing immediately before the trailing edge of the document 1 falls out of the nip between the pair of upper and lower rollers of the sheet discharging roller 28 (the sheet discharging motor 104), as in the case of single-sided sheet discharging. The driving speed of the paper discharge motor 104 is reduced to control the document 1 so as not to fly out of the paper discharge tray 29 (FIG. 9 (J)). The operation is completed by repeating the above operation for the number of originals for which image reading is required.

  In this embodiment, when the document is separated, the driving force is transmitted to the pulley 301, the pulley 302, the gear 305, and the gear 306 when the sheet feeding motor 102 rotates forward as indicated by a solid arrow in FIG. Further, the driving force transmitted to the gears 306 and 307 rotates the sheet feeding belt 9, and the driving force is transmitted to the gear 308, the gear 309, the gear / pulley 310, and the pulley 311, and simultaneously drives the pickup roller 7 and the sheet feeding belt 9 to rotate. It is possible to do. The driving force transmitted to the gears 306 and 314 causes the reverse roller 10 to rotate. At this time, the drive is not transmitted to the gear / pulley 303 coaxial with the gear 305 and the gear 304 coaxial with the gear 314 due to the action of the one-way clutch. When the paper feed motor 102 rotates in the reverse direction during paper feeding, the driving force is transmitted to the pulley 301, the pulley 302, and the gear / pulley 303 to rotate the reverse roller 10 as shown by the broken line in FIG. The driving force transmitted to the gear / pulley 303 and the pulleys 312, 313, 315, and 316 causes the pull-out roller 12, the turn roller 14, and the relay roller 33 to rotate. At this time, the driving force is not transmitted to the gear 305 and the gear 304 coaxial with the gear / pulley 303 by the action of the one-way clutch. In addition, by driving the pickup roller 7 and the paper feed belt 9 by the same drive source, an efficient and compact device configuration can be obtained.

  First Embodiment A first embodiment of the present invention will be described with reference to FIGS. When the copy button on the main body operation unit 211 is pressed down, a document feed signal is issued from the main body control unit 212, and upon receiving this signal, the controller 100 of the apparatus drives the paper feed motor 102 in the normal rotation direction. As shown in FIG. 3, the reverse roller 10 rotates in the direction of returning the original every time the drive is applied in the forward / reverse rotation of the paper feed motor 102. That is, while the paper feed motor 102 is being driven, it always keeps rotating to prevent the subsequent document from entering. Further, the pickup roller 7 and the paper feed belt 9 are stopped when the paper feed motor 102 rotates in the reverse direction without being driven.

  By the normal rotation of the pickup roller 7, the uppermost sheet of the bundle of the original 1 is conveyed to the separation section. The motor speed of the paper feed motor 102 at that time is, for example, about 2300 pps (pulse per second). Since the feed amount per pulse of the stepping motor 102 is 0.253 mm / pulse from the gear ratio, the feed motor 102 rotates at a linear speed of about 580 mm / sec. The uppermost original 1 of the original bundle conveyed by the pickup roller 7 is conveyed to the separation nip of the paper feed belt 9 and the reverse roller 10 and is completely separated into one sheet. The loaded lower original 1 is pushed back by the reverse roller 10. The document 1 separated into one sheet is checked by the butting sensor 11 as to whether it is normally conveyed. The controller 100 has a function of counting the total number of steps from the start of the rotation of the paper feed motor 102, and compares the count value with the state of detection of the leading end of the butting sensor 11 so as to convey the original 1. Can be determined whether a slip has occurred.

  If the oil adheres significantly to the pickup roller 7 or the paper feed belt 9 due to the passage of the oiled original, the main body control unit 212 converts the transport path length into a pulse before the abutting sensor 11 detects the leading end of the original 1. A state occurs where the threshold value is added to the number of pulses for driving the sheet feeding motor 102. Then, the sheet is normally processed as a non-feeding jam. In this example, however, these non-feeding jams can be saved even a little. That is, as described above, the slip of the document 1 occurs when the return force of the reverse roller 10 becomes stronger than the document conveying force of the sheet feeding belt 9 and the pickup roller 7 and the balance of the force is lost. Therefore, by lowering the rotation speed of the reverse roller 10, the balance between the collapsed returning force and the conveying force can be recovered.

  Referring to FIG. After the start of the normal rotation of the paper feed motor 102 (step 1), the controller 100 counts the number of motor pulse application counts or clears a timer counter of an internal timer (step 2). Next, it is detected whether the butting sensor 11 has detected the leading edge of the document 1 (step 3). If the abutment sensor 11 cannot detect the leading end of the document 1, it is determined whether the speed of the paper feed motor 102 is the minimum speed (step 4). It is determined whether or not the counted number of pulses or time exceeds a pulse threshold or a time threshold (step 5). The pulse threshold or the time threshold is the theoretical number of pulses or the time required to convey the document 1 from the pickup roller 7 to the butting sensor 11. If it exceeds, the rotation speed of the paper feed motor 102 is reduced from, for example, 2300 pps to 1500 pps (step 6). When decelerating to 1500 pps, instead of a continuous deceleration operation, it may be stopped once and then restarted to 1500 pps. By lowering the rotation speed of the pickup roller 7 and the paper feed belt 9, the reduced frictional force can be effectively used, and the followability can be improved. Next, the pulse threshold or the time threshold is changed to a value larger than the current value and rewritten (step 7), and the process returns to step 3 to judge whether the butting sensor 11 has detected the leading end of the document 1 and determine whether it is detected. If so, the abutment amount of the document 1 is set, and the remaining pulses required to rotate the paper feed motor 102 are set (step 10).

  If it is determined in step 4 that the speed of the paper feeding motor 102 is the minimum speed, another pulse threshold or time threshold having a value that is significantly larger than the pulse threshold or time threshold in step 5 is counted. Is determined (step 8). If it has exceeded, a non-feeding jam is detected (step 9). If not, return to step 3. As described above, although the time for performing the jam detection and detecting the leading edge of the original 1 varies, the leading edge of the original 1 is detected by the abutting sensor 11 within the total jam detection distance in terms of the amount of advance of the original 1. If it does, the frequency of non-feeding is minimized by not stopping the apparatus. In addition, by setting a value exceeding the threshold value as the threshold value of the jam detection, the sensor-unreached jam after the deceleration is detected, and the jam is stopped when a slip document that cannot be conveyed is passed.

  A second embodiment of the present invention will be described with reference to FIGS. In this embodiment, as shown in FIG. 12, a plurality of sensors are arranged between the separation unit and the pull-out roller 12. In this embodiment, two sensors (abutment sensor 11 and slip detection sensor 500) are arranged. Since it is more effective to make the determination to lower the rotation speed of the roller as early as possible, the slip detection sensor 500 is disposed at a position immediately after one document is separated from the document bundle. The transport path length of the document 1 from the pickup roller 7 to the slip detection sensor 500 is converted into a pulse or a time, and is set as a pulse threshold or a time threshold, respectively. If the number of pulses or the time counted from the start of rotation of the paper feeding motor 102 exceeds the pulse threshold or the time threshold, the motor speed of the paper feeding motor 102 is reduced. The operation of the present embodiment is almost the same as the operation of the first embodiment as shown in FIG. In step 2, after the motor pulse application count is counted or the timer counter of the internal timer is cleared, the leading edge of the document 1 is detected by the slip detection sensor 500. If the leading edge of the document 1 cannot be detected by the slip detection sensor 500, the process proceeds to step 4 and thereafter. If the trailing edge of the document 1 can be detected, it is detected whether the butting sensor 11 has detected the leading edge of the document 1 (step 10). . If the abutting sensor 11 cannot detect the leading edge of the document 1 even if the pulse threshold value or the time threshold value is exceeded, the same determination as in step 8 is performed in step 11 and jam detection is performed (step 12). If the abutment sensor 11 detects the leading end of the original 1, the abutment amount of the original 1 is set, and the remaining pulses required to rotate the paper feed motor 102 are set (step 13).

  A third embodiment of the present invention will be described with reference to FIGS. 2, 11, 13 (A), (B) and (C). In this embodiment, as shown in FIG. 13A, a slip detection sensor 500 is arranged on the upstream side (right side in the drawing) of the separation unit in the document transport direction. This is the most efficient arrangement in a case where a large number of originals are not stacked or an original having a large feeding mass such that the second and subsequent originals are not fed. In some cases, the document cannot be conveyed due to idle rotation of the pickup roller 7 as well as slippage due to the effect of the blocking force of the reverse roller 10. In such a case, the gripping force is increased by reducing the rotation speed. By transporting, non-feeding jams can be reduced. The other operations are as shown in FIG. 11 and are substantially the same as the operations in FIG. FIGS. 13B and 13C are diagrams showing the arrangement of the slip detection sensor 500. FIG.

  Fourth Embodiment A fourth embodiment of the present invention will be described with reference to FIGS. In the present embodiment, as shown in FIG. 14, slip detection sensors 500 and 501 are arranged on the upstream and downstream sides of the separation unit. It is more efficient if there are a plurality of slip detection sensors 501 on the downstream side. In this embodiment, two slip detection sensors are arranged, but the number is not limited to this. When the document 1 exceeds a threshold value set before the document 1 reaches the slip detection sensor 500 on the upstream side, control is performed so that the rotation speed of the roller is reduced from that point. Also, the document 1 that has reached the position detected by the slip detection sensor 500 within a predetermined time often slips due to the effect of the blocking force of the reverse roller 10. By setting the threshold value based on the pulse and time again by the downstream slip detection sensor 501 disposed immediately after the separation unit, slip is detected earlier and the rotation speed of the roller is reduced. That is, the threshold determination in the operation flow of FIG. 11 is performed twice.

  A fifth embodiment of the present invention will be described with reference to FIGS. In this embodiment, as shown in FIG. 15, when the abutment sensor 11 cannot detect the leading end of the document, the rotation speed of the paper feed motor 102 is reduced to a maximum of two times. That is, there are three types of rotation speeds of the paper feeding motor 102. When the leading edge of the document reaches the abutting sensor 11 by the first threshold value, the document is conveyed at 2300 pps without changing the speed (step 5). After the start of the rotation of the paper feed motor 102 (step 1), the controller 100 counts the number of motor pulse application counts or clears a timer counter of an internal timer (step 2). Next, it is detected whether the butting sensor 11 has detected the leading edge of the document 1 (step 3). If the abutting sensor 11 cannot detect the leading end of the document 1, it is determined whether or not the speed of the paper feed motor 102 is the minimum speed (step 4). It is determined whether or not the rotation speed of the paper feed motor 102 has been changed (step 6). If the rotation speed has not been changed, the speed is reduced from, for example, 2300 pps to 1500 pps (step 6). Step 7). Then, the pulse threshold or the time threshold is changed to a value larger than the current value and rewritten (step 8). As a result, the abutment sensor 11 performs detection in a decelerated state. If the leading edge of the document 1 cannot be detected even if the threshold value is exceeded, control for further reducing the motor speed is performed. In this case, since it is determined in step 6 that the motor speed has been changed, the operations in steps 9 and 10 are performed, for example, the motor speed is reduced from 1500 pps to the minimum speed of 1000 pps (step 9). The operations in steps 10 to 12 are the same as those in steps 8 to 10 in FIG.

  A sixth embodiment of the present invention will be described with reference to FIGS. Steps 1, 2, 4 to 9 in FIG. 16 are the same as those in FIG. In the present embodiment, as shown in FIG. 14, slip detection sensors 500 and 501 are arranged on the upstream and downstream sides of the separation unit, and the slip on the downstream side from the upstream slip detection sensor 500 when passing through the separation unit. The transport time up to the detection sensor 501 is compared with the transport time from the start of driving the pickup roller 7 to the slip detection sensor 500 (steps 3 and 12). Thereby, when it is determined that the slip amount due to the reverse roller 10 is small and the idling by the pickup roller 7 is the main cause of the slip, the low speed drive is performed at the time when the slip sensor 501 downstream of the separation unit is passed. Return the motor to the speed at which rotation started. That is, if the tip cannot be detected by the slip detection sensor 501 on the downstream side even after exceeding the threshold or the time set as the threshold (step 14), the motor speed is reduced from, for example, 2300 pps to 1500 pps (step 15). If the tip is detected by the slip detection sensor 501 on the downstream side without exceeding the threshold value or the time set as the threshold value, it is compared with the buffer contents (step 19). In (Step 20), the motor speed is accelerated and returned to the speed at the start of rotation (Step 21), and the operation ends with the detection of the leading end by the butting sensor 11 (Step 22). Operations in other steps are almost the same as those in FIG.

  That is, as shown in FIG. 16, two-step threshold determinations of slip detection by the slip detection sensor 500 and slip detection by the slip detection sensor 501 after passing the slip detection are performed. If there is, control is performed to reduce the speed of the motor. The time required to reach each of the slip detection sensors 500 and 501 is measured and buffered, and when the slip amount at the pickup roller 7 is large and the slip amount at the separation unit is small, the speed of the paper feed motor 102 is reduced again. Set to 2300 pps. This embodiment is effective when the transport path length from the pickup roller 7 to the upstream slip detection sensor 500 is substantially equal to the transport path length from the upstream slip detection sensor 500 to the downstream slip detection sensor 501.

  A seventh embodiment of the present invention will be described with reference to FIGS. Since the basic operation flow is the same as that of FIG. 16, the different points will be described. In this example, when the leading edge of the document 1 is detected by the slip detection sensor 500 on the upstream side, the transport distance on the machine layout, that is, the transport path length is compared with the actual transport distance obtained by converting the time. Calculation is performed to determine the slip ratio at this portion, the obtained value is buffered, and the counter is cleared to measure the slip ratio up to the next detection point (step 10).

  The flow in FIG. 18 shows the details of step 10 in FIG. After calculating and buffering the slip ratio (step 10a), determining whether or not a slip has occurred (step 10b), and clearing the counter when no slip has occurred (step 10f), the process proceeds to step 11 in FIG. In step 10a, when it is recognized that the slip ratio at this portion is a threshold value and that a slip has occurred, for example, it is displayed on the main body operation unit 211 of the image forming apparatus that the replacement time has come (step 10e). . FIG. 19 shows an example of the main body operation unit 211. The display unit 211a at the top displays a message such as "It is time to replace the pickup roller and paper feed belt. Of course, such display can be performed not by the main body of the image forming apparatus but by the ADF 620. Also, the display is not limited to the character display. A simple lamp lighting or blinking may be used.

  Steps 10c and 10d show an optional operation in the case where the display on the main body operation unit 211 is performed when the state determined as the occurrence of the slip occurs two or more times. The number of occurrences of slips is counted and counted, for example, two or three consecutive times. By determining whether or not a slip has occurred based on the count value, the reliability of the display on the main body operation unit 211 is improved.

  Also, even when the leading end of the document 1 is detected by the slip detection sensor 501 on the downstream side, the slip ratio from the slip detection sensor 500 to the slip detection sensor 501 is obtained as in step 10 (step 19). Then, the two slip ratios are compared to determine whether or not the slip is only due to the idle rotation of the pickup roller 7 (step 20). In step 20, “A” indicates a slip at the pickup roller 7, and “B” indicates a slip to the paper feed belt 9. When it is determined that the slip is only due to the idle rotation of the pickup roller 7, in other words, the slip amount of the paper feed belt 90 is equal to or less than a predetermined value, the motor speed change determination as described above is performed. (Step 21) If the motor has already been driven at a low speed, resetting to the original speed is performed again (Step 22). That is, by accelerating the motor speed, it is possible to shorten the time for transporting the original to the pull-out roller 12 and increase the production efficiency. On the other hand, if it is determined that not only the pickup roller 7 but also the paper feed pelt 10 has slipped and slipped at two locations, the motor speed is not accelerated and the abutting sensor 11 detects the leading edge of the original 1. After the presence or absence, the same operation as in the already described embodiment is performed.

In each of the embodiments described above, a method of counting the number of pulses for driving the motor or counting the number of pulses using an encoder can be adopted as the number of pulses. In each of the embodiments described above, a drive source for rotating the pickup roller 7 and a drive source for rotating the sheet feeding belt 9 may be provided separately. In this case, the respective motors are rotated at the same linear speed at the start of sheet feeding. An optimum motor speed can be set for each of the pickup roller 7 and the paper feed belt 9.

  As described above, when the conveyance force of the pickup roller and / or the paper feed belt is significantly reduced and the slip of the sheet material occurs, the conveyance speed of the sheet material is reduced by lowering the rotation speed of the pickup roller. The operation can be continued without sacrificing productivity without causing a non-feeding jam.

  In addition, by counting the number of pulses of the pulse motor that drives the pickup roller and the sheet feeding belt, the speed of the pulse motor changes during the operation, and the time until the sheet material reaches the position detected by the sensor is constant. Even when the condition is not satisfied, the control can be performed by the feed amount of the sheet material, no extra software processing is required, and a simple determination condition can be set as the threshold.

  Further, by detecting the feeding amount of the sheet material by measuring the time and changing the rotation speed of the sheet feeding motor based on the detected information, the present invention can be used in an apparatus that does not use a step motor.

  In addition, by providing a plurality of conditions for changing the speed of the paper feeding motor, for example, a plurality of threshold conditions for reaching the abutting sensor, the rotation speed of the paper feeding motor can be reduced in stages, and the feeding more suitable for the degree of slippage can be achieved. The rotation speed of the paper motor can be set, and the occurrence of non-feeding can be further reduced.

  In addition, once the conveyance speed of the sheet material fed from the pickup roller is changed, and then the conveyance speed of the pickup roller is changed again at a predetermined timing, it is determined whether only slippage due to idle rotation of the pickup roller has occurred. Can be detected, and in that case, the high-speed conveyance is performed again from the point when the sheet has passed through the separation mechanism, so that a decrease in productivity can be minimized.

  In addition, by devising the arrangement of the sensors, the slip of the sheet material can be detected earlier, and the decrease in productivity can be further reduced. For example, by detecting a state in which the sheet material has not yet reached the detection position immediately after being separated into one sheet, reliable slip detection can be performed. Then, a high-quality sheet material can be supplied without interrupting the operation of the apparatus.

  In addition, by disposing the sensors both upstream and downstream of the separation unit, it is possible to distinguish between a case where the slip at the feeding unit is large and a case where the slip at the separation unit is large. By displaying which member causes the slip on the operation screen, it is possible to notify the user that the time for replacing the member has come. Before the paper cannot be completely fed due to an increase in the slip amount due to the deterioration of the members or the like, the replacement of the members can be urged, and the reliability for the user can be improved. The following method can be used to increase the reliability of such display.

  That is, even if one of the bundles of sheet materials is detected as slip, and a slip during continuous conveyance of the next sheet material is detected from a state in which the feeding speed is changed, the fact is displayed on the screen of the operation unit. Display an appropriate message. Then, slips and non-feeding caused by setting the stapled original bundle can be distinguished from other cases, and unnecessary message display can be eliminated.

1 is a cross-sectional view conceptually showing an image forming apparatus such as an electrophotographic copying machine or a printer according to the present invention. FIG. 1 is a cross-sectional view illustrating a basic configuration of a read original document processing apparatus (ADF) according to an embodiment of the present invention. FIG. 2 is a paper feed drive system diagram of FIG. 1. It is the same reading conveyance drive system diagram. It is a lower inversion part drive system diagram. FIG. 3 is a sheet ejection drive system diagram. It is a reverse part drive system diagram same as the above. It is the same electrical equipment block diagram. FIG. 9 is a drive system diagram showing the operation of the same two-sided document when a plurality of sheets are used. FIG. 4 is an operation flowchart of the first embodiment of the present invention. It is an operation | movement flowchart of the 2nd Example. It is a block diagram of the 2nd Example. It is a block diagram (A) of the 3rd Example, and is a figure (B) and (C) which show a slip detection sensor and its arrangement. It is a block diagram of the 4th Example. It is an operation | movement flowchart of the 5th Example. It is an operation | movement flowchart of the 6th Example. It is an operation | movement flowchart of the same 7th Example. It is an operation | movement flowchart of the same 7th Example. It is a figure of a main part operation part and a display part in a 7th example.

Explanation of reference numerals

REFERENCE SIGNS LIST 1 original 2 original table 3 movable original table 4 set filler 5 set sensor 7 pickup roller 8 table rise detection sensor 9 paper feed belt 10 reverse roller 11 butting sensor 12 pullout roller 13 original width sensor 14 turn roller 15 reading entrance sensor 16 reading Inlet roller 17 Registration sensor 19 Reading roller 21 Reading exit roller 22 Discharge sensor 23 Lower reversing switching claw 27 Auxiliary roller 28 Discharging roller 29 Discharge tray 30 Double-side switching claw 31 Upper reversing roller 32 Upper reversing sensor 33 Relay roller 100 ADF controller Reference Signs List 101 Pickup motor 102 Feed motor 103 Reading motor 104 Discharge motor 105 Bottom plate raising motor 106 Lower reversing motor 107 Upper reversing motor 112 Solenoid for double-side switching claw drive 20 The image forming apparatus main body 201 reading portion 211 the manipulation section 211a display unit 212 the main control unit 500 to 501 slip detection sensor 600 reading unit 610 the image forming unit 620 an automatic document feeder (ADF)
640 to 670 paper feed cassette 680 paper feed unit 690 paper discharge unit 611 photoconductor 612 charging device 613 writing unit 614 developing device 615 transfer device 616 cleaning device L laser beam P recording medium

Claims (12)

Feeding means for rotating and feeding the sheet material while abutting on the stacked sheet material,
A rotating member that feeds out the sheet material by rotatingly contacting the fed-out sheet material, and a blocking unit that prevents conveyance of the overlapped and fed-out sheet material, and separates the overlapped and delivered sheet material into one sheet Separation mechanism,
Driving means for driving the feeding means and / or the rotating member;
Sheet material detecting means for detecting the leading edge of the sheet material;
Driving amount detecting means for detecting a driving amount of the driving means,
A sheet material supply device, comprising: a control unit that variably controls a rotation speed of the feeding unit and / or the rotation member based on a detection result of a sheet material front end by the sheet material detection unit. The sheet material supply device according to claim 1,
The control means temporarily changes the rotation speed of the feeding means and / or the rotating member,
Thereafter, when the sheet material detecting means does not detect the leading end of the sheet material and the driving amount of the driving means does not reach a predetermined driving amount, the control means reduces the rotation speed of the feeding means and / or the rotating member. A sheet material supply device characterized by being changed again. The sheet material supply device according to claim 1 or 2,
A sheet material feeding apparatus, wherein the control means has a plurality of threshold values for changing a rotation speed of the feeding means and / or the rotating member. The sheet material supply device according to any one of claims 1 to 3,
A sheet material supply device, wherein at least one sheet material detecting means is disposed downstream of the separation mechanism in a sheet conveying direction. In the sheet material supply device according to claim 4,
A sheet material supply device, wherein at least one sheet material detecting means is disposed on a transport path between the separation mechanism and the feeding means. The sheet material supply device according to any one of claims 1 to 5,
Display means capable of displaying an operation state,
The sheet material detection unit is disposed on the downstream side of the separation mechanism in the sheet conveyance direction, and on a conveyance path between the separation mechanism and the feeding unit,
When the slip amount at the feeding means exceeds a predetermined slip amount, the control means displays information urging replacement of the feeding means on the display means, and the slip amount at the separation mechanism is a predetermined slip amount. When the amount exceeds the amount, the control means displays information urging replacement of the rotating member on the display means. 7. The sheet material feeding apparatus according to claim 6, wherein when the slip amount continuously exceeds a predetermined slip amount, the information is displayed on the display unit. The sheet material supply device according to claim 1, wherein
The sheet supply device, wherein the driving amount detecting unit detects a driving time of the driving unit. The sheet material supply device according to any one of claims 1 to 8,
The driving means is a pulse motor,
The sheet material supply device, wherein the drive amount detection means detects the number of pulses of the pulse motor. The sheet material supply device according to any one of claims 1 to 9,
2. The sheet feeding apparatus according to claim 1, wherein the feeding unit is a pickup roller. An image reading apparatus for feeding a sheet document using the sheet material supply apparatus according to any one of claims 1 to 10. An image forming apparatus for feeding a sheet document using the image reading apparatus according to claim 11.

Images