JP4474139B2 - Sheet material feeding apparatus, image forming apparatus, image reading apparatus, and copying machine - Google Patents

Description

  The present invention relates to a sheet material feeding device, a document reading device, an image forming apparatus, and a copying machine that feed a sheet material accommodated in a sheet material accommodating portion to a processing portion that performs processing on the sheet material.

  In a processing apparatus such as an image forming apparatus or an image reading apparatus, a pair of registration rollers (registration means) is disposed on the upstream side of the image forming section or the image reading section in the sheet material conveyance path, and further on the upstream side of the registration rollers. A conveying roller is disposed on the surface.

  The registration roller controls the timing at which the sheet material is conveyed to a processing unit such as an image forming unit and an image reading unit. The leading end of the sheet material conveyed on the sheet material conveyance path is abutted against the registration roller. At this time, a predetermined amount of bending occurs in the sheet material due to the force acting from the registration rollers. And in order to supply a sheet | seat material to a process part favorably, it was important to generate | occur | produce a moderate bending in a sheet | seat material.

  However, there is a disadvantage that the conveyance force for conveying the sheet material to the position where the registration roller is disposed is reduced due to the deterioration of the conveyance roller with time, and the amount of bending of the sheet material is insufficient. The conveying roller has an elastic member having a high friction coefficient on the surface in order to reliably convey the sheet material. However, the elastic member is worn over time, so that the outer diameter of the conveying roller is reduced, and the conveying roller. A reduction in the coefficient of friction of the surface occurs. And since the rotation speed in a drive source is set based on the outer diameter, the conveyance roller has a problem that the conveyance force of the conveyance roller decreases as the outer diameter of the conveyance roller decreases with time. was there. This problem may be exacerbated by an increase in the number of sheets processed in accordance with recent increases in sheet material conveyance speed.

Therefore, as a technique for coping with deterioration over time of such a conveyance roller, for example, by measuring the time required to convey the sheet material, and adjusting the driving speed of the motor based on the obtained measurement result, Some adjust the time required for the sheet material to reach the resist means (see, for example, Patent Document 1 and Patent Document 2) .

  However, in the prior art including Patent Document 1 and Patent Document 2, there is a concern that the configuration of the apparatus may be complicated, for example, an apparatus for measuring the time required for transporting the sheet is required.

  On the other hand, deterioration with time of the transport roller can be predicted to some extent. For this reason, for example, the amount of bending of the sheet material can be easily adjusted without performing feedback control as in Patent Document 2.

  An object of the present invention is to provide a sheet material feeding apparatus, an image forming apparatus, an image reading apparatus, and a copying machine that can easily adjust the amount of deflection of the sheet material in the registration means.

  The present invention has the following configuration.

(1) a sheet material conveyance path disposed between a sheet material accommodating portion that accommodates the sheet material and a processing portion that performs processing on the sheet material;
A conveying roller that is disposed along the sheet material conveying path and conveys the sheet material to the downstream side in the sheet material conveying direction;
The sheet material is disposed on the downstream side of the conveyance roller in the sheet material conveyance path, the sheet material is temporarily stopped by applying a force to the leading end side of the sheet material conveyed by the conveyance roller, and the sheet material is placed on the processing unit. A registration roller for controlling the conveyance timing, and a registration roller capable of changing a rotation start timing via a registration roller clutch;
Storage means for storing a data table indicating the relationship between the number of sheets processed and the registration value corresponding to the time from when it is detected that the leading edge of the sheet has reached the registration roller until the registration roller starts rotating When,
Control means for controlling the timing at which the registration rollers start rotating so that the amount of deflection of the sheet material becomes substantially constant by controlling the registration roller clutch based on a data table stored in the storage means; ,
With
The data table shows the amount of increase in the resist value every time the number of sheet materials processed in the initial period from the start of use until the number of sheets processed reaches a predetermined value, after the number of sheets processed reaches the predetermined value. In this case, the number of processed sheet materials is larger than the amount of increase in the resist value every time a certain number of sheets are increased .

  In this configuration, the sheet material feeding apparatus includes a sheet material conveyance path, a conveyance roller, a registration unit, a storage unit, and a control unit. The sheet material is conveyed to the downstream side of the sheet material conveyance path by the conveyance roller. On the downstream side of the conveyance roller in the sheet material conveyance path and upstream of the processing unit, registration means for controlling the timing of conveying the sheet material to the processing unit is arranged. A typical example of the registration means is a pair of registration rollers. Note that a closing mechanism that temporarily closes the sheet material conveyance path may be used as the registration means.

  The sheet material conveyed to the downstream side of the sheet material conveyance path by the conveyance roller comes into contact with the registration unit, and stops due to the force of the registration unit. At this time, the sheet material bends according to the amount of force acting on the sheet material from the resist means. The amount of this force is determined by the magnitude, direction, and action time of the force applied to the sheet material from the resist means.

  The present invention pays attention to the fact that the conveying force changes due to the change in the state of the conveying roller over time, and the bending of the sheet material due to the action of the force from the registration means changes. Specifically, in the present invention, the storage unit stores a relationship between an expected state change of the conveying roller with time and a deflection amount of the sheet material. Further, the stored contents of the storage means are used for the control means. Then, the control means controls at least one of the conveying roller and the registration means so that the bending of the sheet material becomes substantially constant regardless of the change of the conveying roller with time.

( 2 ) An image forming apparatus in which a sheet material conveyance path is formed between a sheet material container and an image forming unit, and an image forming process is performed on the sheet material in the image forming unit,
The sheet material feeding device according to (1 ) is provided.

  In this configuration, a sheet material feeding device capable of adjusting the bending of the sheet material is mounted on the image forming apparatus. Here, a printer is a typical example of the image forming apparatus.

( 3 ) An image reading apparatus in which a sheet material conveyance path is formed between the sheet material container and the image reading unit, and the image reading unit performs an image reading process on the sheet material.
The sheet material feeding device according to (1 ) is provided.

  In this configuration, a sheet material feeding device capable of adjusting the bending of the sheet material is mounted on the image reading device. Here, a scanner is a typical example of the image reading apparatus.

( 4 ) A copying machine that performs an image forming process based on an image read by an image reading unit,
The image reading apparatus according to ( 3 ) is provided.

  In this configuration, a sheet material feeding device capable of adjusting the deflection of the sheet material is mounted on the copying machine. Here, a copy machine is a typical example of a copying machine.

  According to the present invention, the following effects can be obtained.

(1) The amount of force acting on the sheet material from the registration means can be automatically adjusted according to the predicted change in the state of the conveying roller. For this reason, it is possible to prevent a trouble caused by a conveyance failure of the sheet material in the processing unit with a simple configuration.

(2) By referring to the data table, it is possible to quickly grasp the operation contents for maintaining the amount of force acting on the sheet material from the registration means almost always, and the processing speed of the sheet material feeding device It becomes possible to improve.

(3) Even if the outer diameter of the conveying roller decreases with time or the frictional force on the surface of the conveying roller decreases, the conveying force of the conveying roller is adjusted to act on the sheet material from the resist means. It is possible to keep the amount of force almost constant.

(4) Regardless of the change in the state of the transport roller over time, it is possible to maintain the sheet material deflection caused by the force applied from the registration means to the sheet material substantially constant.

(5) Regardless of the change in the state of the transport roller over time, it is possible to maintain the sheet material flexure caused by the force applied from the registration means to the sheet material substantially constant. In particular, the bending of the sheet material can be maintained substantially constant without changing the timing for operating the registration means.

(6) Even if the conveyance speed deteriorates with time, it is possible to prevent the conveyance force of the conveyance roller from decreasing. In addition, it becomes possible to keep the amount of bending of the sheet material within a certain range regardless of the deterioration of the conveying roller with time.

(7) It is possible to prevent the sheet material from being poorly conveyed in the image forming unit, and the image forming process can be performed stably.

(8) It is possible to prevent the sheet material from being poorly conveyed in the image reading unit, and it is possible to stably perform the image reading process.

(9) It is possible to prevent the sheet material from being poorly conveyed in the image forming unit, and it is possible to stably perform the copying process.

  In the following, embodiments of the document conveying device, the document forming device, the image reading device, and the copying machine of the present invention are provided with reference to the drawings.

  FIG. 1 is a perspective view illustrating a configuration of a copying machine 100 according to the first embodiment. As shown in the figure, the copying machine 100 includes a document reading unit 1 that reads image data of a document, and an image forming unit 2 that executes image forming processing based on the image data read by the document reading unit 1.

  FIG. 2 is a diagram showing a schematic configuration inside the copying machine 100. As shown in the figure, the document reading unit 1 is configured of a platen glass 21 (21A, 21B) on which a document is placed, and an image of the document placed on the document table 21 (21A, 21B). A scanner optical system 10 for reading and a document transport device 30 for sequentially transporting documents stacked on the document tray 31 to a document reading position on the document table 21 (21A, 21B) are provided. In the present embodiment, the document reading unit 1 constitutes the document reading device of the present invention.

  FIG. 3 is a diagram illustrating an internal configuration of the document reading unit 1. The scanner optical system 10 is disposed below the document table 21 (21A, 21B), and includes a light source unit 13, a mirror unit 14, an imaging lens 11, and a photoelectric conversion element (hereinafter referred to as a CCD) 12. Yes. The light source unit 13 includes a light source 13A that emits illumination light for reading a document, a concave reflector 13B that condenses the illumination light for reading emitted from the light source 13A at a predetermined reading position on the document table 21, and the document. 13C, and a mirror 13D having a reflecting surface inclined by 45 degrees with respect to the surface of the document table 21 in order to change the optical path of the light passing through the slit 13C by 90 degrees.

  The mirror unit 14 has a pair of mirrors 14 (14A, 14B) arranged so that the reflection surfaces are orthogonal to each other in order to guide the light reflected by the mirror 13D in the light source unit 13 to the CCD 12.

  The light source unit 13 and the mirror unit 14 are configured to reciprocate in a direction parallel to the document table 21 indicated by an arrow A. Here, the arrangement position P1 of the light source unit 13 shown in the drawing is a traveling document reading position, the arrangement position P2 is a stationary document reading start position, and the arrangement position P3 is a return position at the time of maximum document reading. Further, in order to make the optical path length from the original to the CCD 12 constant, the moving speed of the mirror unit 14 is set to half of the moving speed of the light source unit 13. The light source unit 13 and the mirror unit 14 are moved by a stepping motor, a servo motor, or the like.

  The imaging lens 11 forms an image of the reflected light from the original on the CCD 12. The CCD 12 generates an electrical signal based on the reflected light from the document. Here, the imaging lens 11 and the CCD 12 constitute a CCD reading unit.

  A document mat 5 made of an elastic material is disposed on the bottom surface of the document conveying device 30 that faces the document table 21 (21A, 21B) when the document conveying device 30 reads. Further, as shown in FIG. 3, in the document conveying device 30, a document conveying path R having a two-stage structure including a curved portion from the document tray 31 through the document reading position to the sheet discharge tray 32, that is, A document conveyance path R having a horizontal U-shape with the U-shape inclined about 90 degrees to the left is formed. Along the document conveyance path R, the uppermost document accommodated in the document tray 31 from the upstream side is picked up by the pulling roller 41, and the document picked up by the pulling roller 41 is separated to double transport the document. Separating / conveying roller 42 for preventing the paper, conveying rollers 43 to 45 for conveying the document that has passed the separating / conveying roller 42 further downstream of the document conveying path R, and a registration roller for adjusting the timing for guiding the document to the document reading position 46 is arranged. In this embodiment, the registration roller 46 constitutes the registration means of the present invention.

  A plurality of detectors for detecting a document are disposed between the document tray 31 and the paper discharge tray 32 via the document transport path R. The document tray 31 is provided with a document detector 51 for detecting the presence or absence of a document, and a first size detection sensor 50 and a second size detection sensor 57 for detecting a document size. A document size detector 69 is disposed below the document table 21A. Furthermore, from the upstream side along the document transport path R, a call roller position detector 52 for detecting the position of the call roller 41 in the height direction, and paper feed detectors 53 to 55 for detecting a fed document, Is arranged. Each of these paper feed detectors 53 to 55 outputs a predetermined signal to the control unit 41 described later when the conveyance of the paper is detected. In this embodiment, the rotation start timing of the registration roller 46 is controlled by a signal output from the paper feed detector 55.

  A CIS (Contact Image Sensor) 21 is disposed on the opposite side of the document table 21B across the document conveyance path R so as to face the document table 21B. The CIS 21 includes, for example, an image sensor and a light guide (lens array such as a SELFOC lens) arranged in an array, a light source (LED array light source or fluorescent lamp), and the like.

  In the document transport path R, the document is transported downstream by the transport rollers 43 to 45. Whether or not the document is transported properly on the document transport path R is detected by the paper feed detectors 53 to 55. The The curved portion in the document transport path R has a curvature that can stably transport all kinds of documents, and the thickest document among the readable documents, that is, the document with the highest waist can be smoothly smoothed. It has a curvature that can be conveyed.

  On the downstream side of the curved portion in the document transport path R, a resist / skew correction region 6 is formed so that an inclination angle with respect to the document table 21 (21A, 21B) becomes small. The alignment of the leading edge of the document is executed in the skew correction region 6.

  In the registration / skew correction region 6, the conveyance roller 45 and the registration roller 46 can correct the registration and skew of the document between the conveyance roller 45 located on the downstream side of the document conveyance path R and the registration roller 46. The state of the original surface is substantially flat and the friction with the guide surface of the original conveyance path R is reduced. In the registration / skew correction region 6, the leading edge of the sheet conveyed by the conveying roller 45 is abutted against the registration roller 46, and an appropriate amount of bending occurs in the sheet. It should be noted that the distance between the conveyance roller 45 and the registration roller 46 only needs to be larger than the length in the conveyance direction of the minimum size document among the documents that can be processed as the document conveyance device.

  Here, the description will be made again with reference to FIG. As shown in the figure, the image forming unit 2 is disposed below the image reading unit 1. In this embodiment, the image forming unit constitutes the image forming apparatus of the present invention. The image forming unit 2 includes a plurality of paper cassettes (251, 252, 253) for storing paper on which image forming processing is performed, and a manual feed tray 254 for manually setting paper on which image forming processing is performed. ing. In the vicinity of the paper cassettes (251, 252, 253) and the manual feed tray 254, a pickup roller 41 'for picking up the uppermost paper stored therein and a separation / conveyance roller 42' for preventing double feeding of the paper Is arranged.

  Further, the image forming unit 2 includes a paper discharge roller 219 for discharging the paper on which the image forming process has been performed to the outside of the image forming unit 2. A paper transport path R ′ is formed between the paper cassettes (251, 252, 253) and the manual feed tray 254 and the paper discharge roller 219. A photosensitive drum 222 as an image carrier is disposed in the vicinity of the sheet conveyance path R ′.

  Around the photosensitive drum 222, a charging device 223, an exposure device 227, a developing device 224, a transfer device 225, a charge eliminating device 226, and a cleaning device 226 are disposed. The charger 223 charges the photosensitive drum 222 to a predetermined potential. The exposure device 227 forms an electrostatic latent image on the photosensitive drum 222 based on the input image data. The developing device 224 supplies a developer to the electrostatic latent image formed on the photosensitive drum 222 to form a developer image. The transfer device 225 transfers the developer image formed on the surface of the photosensitive drum 222 onto the paper on the paper transport path R ′. The static eliminator 226 neutralizes the surface of the photosensitive drum 222. The cleaning device 226 collects an excessive developer image attached on the photosensitive drum 222.

  A registration roller 46 ′ and a paper feed detector 55 ′ are arranged on the upstream side of the transfer position between the photosensitive drum 222 and the transfer device 225 in the paper transport path R ′. Conveying rollers (45 ', 44', 43 ') for conveying the paper are disposed upstream of the registration roller 46' and the paper feed detector 55 'in the paper conveying direction.

  A fixing roller 217 is disposed on the downstream side of the transfer position in the sheet conveyance path R ′. The fixing roller 217 fixes the unfixed developer image attached to the paper to the paper. A flapper is disposed between the fixing roller 217 and the paper discharge roller 219 in the paper transport path R ′. The flapper 219 switches the transport destination of the paper on which the image forming process has been performed to either the paper discharge roller or the switchback transport path 221.

  During double-sided printing, the leading edge and trailing edge of the paper are reversed in the switchback conveyance path 221. The switchback transport path 221 communicates with the duplex unit 255. For this reason, the sheet to be printed on both sides is conveyed again to the transfer position via the switchback conveyance path 221 and the duplex unit 255.

  FIG. 4 is a block diagram showing the configuration of the copying machine 100. As shown in FIG. The copying machine 100 includes a control unit 41. The control unit 41 includes a scanner optical system 10, a size detection sensor 57, a size detection sensor 50, a lift motor 61, a document detector 51, a counter 62, a call roller position detector 52, paper feed detectors 53 to 55, a call The insertion clutch 63, registration roller clutch 64, document transport motor 65, paper discharge detector 56, storage unit 66, CIS 15, and operation unit 71 are electrically connected.

  The scanner optical system 10 is provided with a scanning motor 68 such as a step pink motor and a light source unit detector 67 in addition to the above-described components. The counter 62 counts the total number of times the document reading process has been executed. The elevating motor 61 is a drive source for the elevating plate that contacts the bottom surface of the document. The operation unit 71 receives a command input from the user to the copying machine 100. The storage unit 66 stores a correction table described later. Here, the memory | storage part 66 comprises the memory | storage means of this invention.

  The document transport motor 65 transmits driving force to each of the drawing roller 41, the separation / conveyance roller 42, the transport rollers 43 to 45, the registration roller 46, and the paper discharge roller 47. In this embodiment, the conveyance rollers 43 to 45 and the paper discharge roller 47 start rotating after the supply and conveyance of the original document is started, and continue to rotate until the original document is discharged to the discharge tray 32.

  The registration roller clutch 64 controls the rotation / stop of the registration roller 46 by switching on / off the rotational driving force transmitted from the document conveying motor 65 to the registration roller 46. The registration roller 46 is normally stopped and rotates only when the document is guided to the document reading position at a certain timing. The operation of the registration roller clutch 64 is controlled based on a signal output from the paper feed detector 55 when the leading edge and the trailing edge of the conveyed document are detected.

  The copying machine 100 is characterized in that even when the above-described transport rollers 43 to 45 are deteriorated with time, control is performed so that a substantially constant force is applied from the registration rollers 46 to the document.

  FIG. 5 is a diagram illustrating the relationship between the number of document processed sheets and the outer diameters of the transport rollers 43 to 45. As shown by the curve in the figure, the outer diameters of the transport rollers 43 to 45 generally decrease rapidly from the start of use to the 200,000th sheet. When the number of documents processed exceeds 200,000, the outer diameters of the transport rollers 43 to 45 gradually decrease thereafter.

  FIG. 6 shows the influence of a decrease in the outer diameter of the transport rollers 43 to 45. In this embodiment, the copying machine 100 is set so that the registration roller 46 rotates 166 msec after the paper feed detector 55 detects the leading edge of the document. Further, the document conveyance speed in the copying machine 100 is set to 225 mm / sec.

  The same roller member is used as each of the transport rollers 43 to 45, and an elastic member having a high friction coefficient is provided on the surface in order to reliably transport the document. As shown in the figure, the outer diameter of the transport rollers 43 to 45 before use is 16.150 mm. At this time, the leading edge of the conveyed document is abutted against the registration roller 46, and a force acts from the registration roller 46, thereby causing the document to bend by 2.42 mm.

  When the number of originals to be processed is about 100,000, the outer diameters of the transport rollers 43 to 45 are reduced by about 1.9% to 15.845 mm. At this time, the deflection generated in the document due to the force acting on the leading edge of the document from the registration roller 46 is reduced to 1.71 mm.

  When the number of documents processed is about 200,000, the outer diameters of the transport rollers 43 to 45 are reduced by about 2.3% to 15.776 mm. At this time, the amount of bending of the original is further reduced to 1.55 mm. Furthermore, when the number of processed documents reaches about 800,000, the outer diameters of the transport rollers 43 to 45 are reduced by about 4.6% to 15.410 mm. At this time, the amount of bending of the document is only 0.69 mm.

  As described above, as the number of documents processed increases, the amount of document deflection significantly decreases. For this reason, when the conveyance of the document temporarily stopped by the registration roller 46 is restarted and the document is guided to the document reading position, a conveyance failure is likely to occur.

  Therefore, in the present embodiment, the time from when the paper feed detector 55 detects the leading edge of the document to when the registration roller 46 starts rotating is adjusted according to the decrease in the outer diameter of the transport rollers 43 to 45. The document is adjusted so that the amount of bending of the document becomes substantially constant regardless of the change of the conveying roller with time. Here, the amount of bending is substantially constant means a range of plus or minus 0.10 mm of a reference amount of bending (here, 2.42 mm). However, the “substantially constant range”, that is, the range of the amount of deflection allowed for good conveyance can be set to an optimum range according to the use environment regardless of the value of this embodiment.

  As described above, the reference time (reference time T) from when the paper feed detector 55 detects the leading edge of the document to when the registration roller 46 starts rotating is 166 msec. Here, the corrected time T ′ is calculated by adding the correction amount according to the number of originals conveyed to the reference time T. Then, when the post-correction time T ′ elapses after the paper feed detector 55 detects the leading edge of the document, the rotation of the registration roller 46 is started.

  FIG. 7 shows a data table stored in the storage unit 66, and shows the relationship between the number of documents processed and the registration value. Here, the resist value is expressed in 100 steps from 0 to 99. The registration value is set to “50” when there is no need for correction. In this embodiment, every time the resist value increases by 1, the post-correction time T ′ increases by 1. On the contrary, every time the resist value decreases by 1, the post-correction time T ′ decreases by 1.

  Since the resist value at which the deflection is appropriate differs for each apparatus, the resist value can be changed and set even in the initial stage. FIG. 7 shows an example in which “50” is set as a resist value that can obtain an appropriate deflection in the initial stage, and this is stored as a data table. That is, when the registration value is set to “47” in the initial stage, 3 is subtracted from the registration value to be applied when the number is 100,000 (100K) to 800,000 (800K). Specifically, in FIG. 7, control is performed with a registration value of “50” for 100,000 sheets (100K) and “51” for 200,000 sheets (200K).

  FIG. 7 shows registration values to be applied when the number of originals conveyed is 100,000 (100K) to 800,000 (800K). In the copying machine 100 of the present embodiment, the control unit 41 determines the timing for turning on the registration roller clutch 64 with reference to the data table.

  FIG. 8 shows an example of the deflection amount adjustment control in the copying machine 100. The amount of bending of the document is adjusted by controlling the rotation start timing of the registration roller 46 in a state where the conveying rollers 43 to 45 are continuously rotated. As a result, the force acting on the document from the registration roller 46 is adjusted to be substantially constant. As shown in FIG. 6, the corrected deflection amount is maintained in the range of 2.36 mm to 2.42 mm regardless of the decrease in the outer diameter of the transport rollers 43 to 45.

  FIG. 9 shows another example of bending amount adjustment control in the copying machine 100. In the control in FIG. 9, the time from when the leading edge of the document is detected by the paper feed detector 55 to when the rotation of the transport roller 45 is stopped is adjusted. When the leading edge of the document is detected by the paper feed detector 55, the document contacts the registration roller 46 after a certain time. Therefore, in the control in FIG. 9, the time for stopping the rotation of the conveying roller 45 after the leading edge of the document comes into contact with the registration roller 46 is adjusted. As a result, the force acting on the document from the registration roller 46 can be adjusted, and the amount of bending of the document can be adjusted. This control is performed by means (not shown) such as a clutch for controlling the rotation of the transport roller 45.

  In the control in FIG. 9, for example, the timing for stopping the rotation of the conveyance roller 45 is delayed as the registration value becomes larger than 50, and the timing for stopping the rotation of the conveyance roller 45 is advanced as the registration value becomes smaller than 50. Good. Such control can be effectively used when the rotation start timing of the registration roller 46 is fixed in order to match the timing of the image forming process on the photosensitive drum 222.

As described above, in the present embodiment, the correspondence between the rotation start timing of the registration roller 46 and the rotation stop timing of the conveyance roller 45 and the registration value, and the relationship between the number of document conveyance processing and the registration value to be applied are stored in the storage unit 66. Therefore, the control unit 41 can easily adjust the amount of bending of the document based on the stored contents of the storage unit 66.

  In the above-described embodiment, the control contents of the registration roller 46 and the conveyance rollers 43 to 45 disposed in the document reading unit 1 have been described, but the same control is performed on the registration roller 46 disposed in the image forming unit 2. 'And the control contents of the transport rollers 43' to 45 'can be used. This makes it possible to keep the deflection of the sheet guided to the image forming position substantially constant.

  Furthermore, the control for adjusting the amount of bending of the sheet material including the original and the paper is not limited to the above-described control. For example, control suitable for the use state of the copying machine 100 is adopted, such as controlling the document transport motor 65 based on the registration value stored in the document storage unit 66 and adjusting the rotation speed of the transport rollers 43 to 45. can do. In this case, the rotation speed of the conveyance rollers 43 to 45 increases as the registration value becomes larger than 50, and the rotation speed of the conveyance rollers 43 to 45 decreases as the registration value becomes smaller than 50.

1 is a perspective view showing a configuration of a copying machine according to the present invention. 1 is a diagram showing an outline of an internal configuration of a copying machine according to the present invention. It is a figure which shows the internal structure of an image reading part. 1 is a block diagram showing a configuration of a copying machine according to the present invention. It is a figure which shows the relationship between the number of sheets of a sheet material, and the outer diameter of a conveyance roller. It is a figure which shows the effect of this invention. It is a figure which shows the relationship between the number of sheets processed, and a resist value (correction value). It is a figure which shows an example of the method of adjusting the bending of the sheet | seat material in the copying machine of this invention. It is a figure which shows an example of the method of adjusting the bending of the sheet | seat material in the copying machine of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1- Image reading part 2- Image formation part 41- Control part 45- Conveyance roller 46- Registration roller 55- Paper feed detector 100- Copy machine

Claims (4)

A sheet material conveyance path disposed between a sheet material accommodating portion that accommodates the sheet material and a processing portion that performs processing on the sheet material;
A conveying roller that is disposed along the sheet material conveying path and conveys the sheet material to the downstream side in the sheet material conveying direction;
The sheet material is disposed on the downstream side of the conveyance roller in the sheet material conveyance path, the sheet material is temporarily stopped by applying a force to the leading end side of the sheet material conveyed by the conveyance roller, and the sheet material is placed on the processing unit. A registration roller for controlling the conveyance timing, and a registration roller capable of changing a rotation start timing via a registration roller clutch;
Storage means for storing a data table indicating the relationship between the number of sheets processed and the registration value corresponding to the time from when it is detected that the leading edge of the sheet has reached the registration roller until the registration roller starts rotating When,
Control means for controlling the timing at which the registration rollers start rotating so that the amount of deflection of the sheet material becomes substantially constant by controlling the registration roller clutch based on a data table stored in the storage means; ,
With
The data table shows the amount of increase in the resist value every time the number of sheet materials processed in the initial period from the start of use until the number of sheets processed reaches a predetermined value, after the number of sheets processed reaches the predetermined value. The sheet material feeding apparatus is characterized in that the sheet material processing number in the sheet is larger than the increment of the resist value every time the fixed number of sheets is increased . An image forming apparatus in which a sheet material conveyance path is formed between a sheet material storage unit and an image forming unit, and an image forming process is performed on the sheet material in the image forming unit,
An image forming apparatus comprising the sheet material feeding device according to claim 1. An image reading apparatus in which a sheet material conveyance path is formed between a sheet material storage unit and an image reading unit, and performs image reading processing on a sheet material in the image reading unit,
An image reading apparatus comprising the sheet material feeding device according to claim 1. A copying machine that performs image forming processing based on an image read by an image reading unit,
A copying machine comprising the image reading apparatus according to claim 3.

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