JP2009190877A - Paper feeder for image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder for an image forming device, determining the quality of a backside of used paper fed from a manual backside paper feeder and feeding only the high-quality backside of the used paper, for reusing the rear surface of recording paper (backside of the used paper) with an image recorded on a front surface. <P>SOLUTION: The backside of the used paper fed from the manual backside paper feeder 44 is conveyed to a bypass conveyance path 46. A backside paper processing section 60 provided on the bypass conveyance path 46 is composed of an auxiliary separating device 61, a paper powder removing device 65, a waviness detection device 71, and the like. The auxiliary separating device 61 separates the backside of the used paper double fed (fed together), and the paper powder removing device 65 removes paper powder or the like. Further, the waviness detection device 71 detects the waviness (corrugation) of the backside of the used paper, and only the reusable high quality backside of the used paper having few waviness is conveyed to a first paper feeding cassette, and waits to be fed. The non-reusable backside of the used paper having large waviness is conveyed to a waste paper stacker 42, and is not fed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to a paper feeding device of an image forming apparatus such as a copying machine or a printer.

  In an image forming apparatus such as a copying machine or a printer, in addition to an image reading unit that reads a document image, an image forming unit that forms a read image as a visible image on the surface of an image carrier, a paper feeding unit to an image forming unit A paper feed unit that feeds the recording paper toward the head, a paper discharge unit that ejects the recording paper on which an image formed by the image forming unit is recorded, and the like are provided.

  Briefly explaining the image forming operation of the image forming unit, a laser beam modulated by the image signal output from the image reading unit is projected onto the surface of the image carrier whose surface is uniformly charged, and an image latent image is formed. It is formed. The formed image latent image is developed with toner loaded in the developing device, and a toner image is formed on the surface of the image carrier. The formed toner image is transferred and fixed on the recording paper fed from the paper feeding unit to the transfer position, and the recording paper with the image formed on the surface is ejected to the paper ejection tray of the paper ejection unit.

  In such an image forming apparatus, recently, as part of environmental conservation, there is a case where the back side of a used recording paper (hereinafter referred to as a back paper) on which an image is recorded is used or recycled paper is used. However, when such backing paper or recycled paper is used as recording paper, the friction on the surface of the recording paper is large, and there is a large difference in surface friction depending on the type and state of the recording paper.

  For this reason, in a configuration in which, for example, a pickup roller is brought into contact with the uppermost recording paper loaded in a paper feeding cassette and the recording paper is fed by rotation as in a paper feeding device of a conventional image forming apparatus, the uppermost recording is performed. In some cases, one or a plurality of recording sheets under the sheet may also be “taken” (hereinafter referred to as “multiple feeding”) that is sent out by friction between the recording sheets.

  As a countermeasure, a pressing roller and a bending roller are provided in addition to the pickup roller. When feeding is started, the pressing roller is brought into contact with the recording paper while the rotation of the pressing roller is stopped. There has been proposed one in which recording sheets are separated from each other by rotation and only the uppermost recording sheet is fed (see Patent Document 1).

In addition, for example, there has been proposed a recording paper turning means provided in a paper feeding cassette, and only the topmost recording paper loaded in the paper feeding cassette is turned and fed by the turning means (see Patent Document 2). .
JP 2002-187638 A JP-A-9-278200

  The conventional paper feeding means for preventing double feeding of recording paper is a paper feeding means for preventing double feeding in a paper feeding cassette, and is not necessarily suitable as a paper feeding means when using a back paper. In other words, unlike unused recording paper, the end of the paper bundle is not aligned properly, and paper dust and dust are attached to the recording paper. There has been a need to improve the paper passing quality of the paper feeding means, such as when a jam occurs or the paper is conveyed at an angle.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a paper feeding device of an image forming apparatus provided with a paper feeding means that can feed and transport paper with a high paper passing quality even when using a back paper. To do.

The present invention solves the above-mentioned problems, and the invention according to claim 1 includes an image forming unit that forms an image on a recording sheet, and a plurality of sheet feeding units including a manual sheet feeding device that feeds the recording sheet. In the paper feeding device of the image forming apparatus that feeds the image forming unit from any one of the selected plurality of paper feeding means, whether or not the recording paper fed from the manual paper feeding device is used is inappropriate. A detour conveyance path to be determined, a return conveyance path for conveying the recording sheet conveyed from the detour conveyance path to a sheet feeding means other than the manual sheet feeding device, and a disposal recording sheet for storing a disposal recording sheet that is not suitable for image recording Storage means, and when recording paper inappropriate for use is found in the recording paper transported through the return transport path via the detour transport path, the recording paper is transported as waste recording paper to the waste recording paper storage means. 1 is a sheet feeding device of a featured image forming apparatus.

  A plurality of paper feeding units other than the manual paper feeding device are paper feeding units capable of storing the recording paper conveyed from the return conveyance path.

  On the detour conveyance path, auxiliary papering means, paper dust removing means, and recording paper distortion detecting means for determining whether or not the recording paper is used are arranged.

  In addition, a plurality of paper feeding units other than the manual paper feeding device include a regulation plate for aligning the stored recording paper.

  Further, the paper feeding device of the image forming apparatus includes a paper feeding unit that stores the recording paper according to a degree of the recording paper distortion detected by the recording paper distortion detecting unit arranged on the detour conveyance path, or Assume that the waste recording paper storage means is selected.

  As described above, the feature of the present invention is that the bypass conveyance path for determining whether or not the recording sheet fed from the manual sheet feeder is appropriate and the manual feeding of the recording sheet conveyed from the bypass conveyance path. A recording paper transporting the return transport path through the detour transport path, comprising a return transport path for transporting to a paper feed means other than the apparatus and a waste recording paper storage means for storing a waste recording paper unsuitable for image recording; When an unsuitable recording paper is found, the recording paper is conveyed to a waste recording paper storage means as a waste recording paper.

  With this configuration, the back side of the recording paper on which the image is recorded is reused (hereinafter referred to as the back paper). Therefore, when the back paper is fed from the manual paper feeding device, the back paper is moved along the detour conveyance path. Determine whether or not recording paper is suitable for use, and if there is no distortion often found on the backing paper, or if it can be reused even if there is some distortion, it is stored in the paper feeding means and re-feeded. If the recording paper is unsuitable to be reused as recording paper because it has been detected as being distorted, the recording paper is transported to the waste recording paper storage means and prohibited from being used. Can be selected and fed.

  Hereinafter, a paper feeding device of an image forming apparatus according to an embodiment of the present invention will be described.

  FIG. 1 is a front sectional view for explaining the outline of a sheet feeding device of an image forming apparatus according to an embodiment of the present invention. A document table 12 is disposed on the upper surface of the image forming apparatus 1 and a scanner 13 is disposed on the lower surface thereof. The image reading unit 10 is arranged. The scanner 13 reads a document image placed on the document table 12 and outputs it as an image signal to an image forming unit 20 described later.

  The image forming unit 20 includes a charging roller 22, a laser beam device 23 that projects laser light modulated by an image signal onto the photosensitive member 21, a developing device 24, and the like around a photosensitive member 21 that rotates at a predetermined constant speed. The transfer roller 25 and a cleaning device 26 that cleans toner remaining on the photoreceptor 21 are configured.

  The fixing unit 30 fixes the toner image transferred onto the recording paper (including the backing paper) conveyed from the image forming unit 20. The fixing unit 30 includes a fixing roller 31, a pressure roller 32, and an inside of the fixing roller 31. It is comprised from the fixing heater 33 arrange | positioned.

  Next, the paper feed unit 40 will be described. In the image forming apparatus according to this embodiment, the paper feed unit 40 is a first paper feed cassette 41, a second paper feed cassette 43, a waste paper stacker 42 as waste recording paper storage means, and a manual paper feed device. A manual back paper feeding device 44 is provided. It should be noted that the manual backsheet paper feeding device 44 can also be used as a normal manual paper feeding device.

  The paper feed unit 40 is provided with a normal conveyance path 45 that conveys the recording paper, a detour conveyance path 46, a discharge conveyance path 47, and a return conveyance path 48.

  The normal conveyance path 45 is a conveyance path for conveying the recording paper fed from the paper feed cassette to the fixing unit 30 through the image forming unit 20.

  The detour conveyance path 46 is a conveyance path that branches from the upstream side of the image forming unit 20 of the normal conveyance path 45 and goes to the return conveyance path 48 via the backing paper processing unit 60.

  The return conveyance path 48 is a conveyance path for conveying the backing paper processed by the backing paper processing unit 60 to the first paper feeding cassette 41, the second paper feeding cassette 43, and the waste paper stacker 42.

  A plurality of transport rollers are arranged in the normal transport path 45, the detour transport path 46, the discharge transport path 47, and the return transport path 48, and configured to transport the recording paper in the transport direction.

  A first switching guide 51 is arranged at a branch portion between the normal conveyance path 45 and the detour conveyance path 46, and the conveyance path is switched by a solenoid controlled by a control device (not shown).

  On the return conveyance path 48, a second switching guide 52 for directing the recording paper to be conveyed to the first paper feed cassette 41 and a third switching guide 53 for directing the recording paper to be conveyed to the waste paper stacker 42 are arranged. Has been.

  The configurations and operations of the first paper feed cassette 41, the second paper feed cassette 43, the waste paper stacker 42, the manual back paper feed device 44, and the back paper processing unit 60 will be described in detail later. Next, the operation of the recording paper conveyance device of the image forming apparatus will be described.

  First, a power supply is turned on to drive a motor (not shown) to start a preparation operation for an image forming operation, such as starting rotation of the photosensitive member 21 of the image forming apparatus and the conveyance roller of the recording paper conveyance apparatus. An original image is placed on the original platen 12, and the start of an image forming operation is instructed from an operation panel (not shown).

  The scanner 13 reads a document image on the document table 12 and outputs it as an image signal to the laser beam device 23 of the image forming unit 20.

  The surface of the photoreceptor 21 of the image forming unit 20 is uniformly charged by the charging roller 22. Laser light modulated by an image signal is projected from the laser light device 23 onto the surface of the photoconductor 21 to form an image latent image. The latent image formed on the surface of the photosensitive member 21 is developed with toner loaded in the developing device 24 to form a toner image.

  In accordance with the timing at which the toner image formed on the surface of the photosensitive member 21 moves to the transfer position, the recording paper P having a desired size is transferred from either the first paper feed cassette 41 or the second paper feed cassette 43 to the normal conveyance path 45. The toner image on the surface of the photosensitive member is transferred onto the recording paper (including the back paper) by the action of the transfer roller 25 at the transfer position.

  The recording paper (including the backing paper) onto which the toner image has been transferred is conveyed to the fixing unit 30 and passes between the fixing roller 31 and the pressure roller 32 that are in pressure contact with each other, and is subjected to fixing processing. The recording sheet P that has been subjected to the fixing process is discharged to a discharge tray (not shown) through a discharge conveyance path 48, and one image forming process is completed. The toner remaining on the photosensitive member 21 without being transferred to the recording paper P is cleaned by the cleaning device 26.

  The above is the case where the recording paper is fed from either the first paper feeding cassette 41 or the second paper feeding cassette 43, but the recording paper or backing paper R that is not the backing paper is supplied from the manual-feed backing paper feeding device 44. Can also be fed. In this case, the first switching guide 51 is set so that the fed recording paper or backing paper R is directed toward the image forming unit 20, and the recording paper or backing paper fed from the manual backing paper feeder 44. R is conveyed to the transfer position of the image forming unit 20. The processing after the transfer processing of the toner image formed on the surface of the photoreceptor 21 is the same as the processing when the paper is fed from the paper feeding cassette.

  Next, the manual sheet feeding device 44 and the sheet R feeding operation will be described. 2A and 2B are diagrams for explaining the configuration and operation of the manual paper backing device 44. FIG. 2A is a front view of the manual paper backing device 44, and FIG. FIG. 2C is a cross-sectional view, FIG. 2C is an enlarged view near the side regulation, and FIG. 2D is a diagram for explaining a state in which the back paper R on the manual back paper feed table is reduced.

  With reference to FIGS. 2A to 2D, the configuration and operation of the manual-back backing paper feeder 44 will be described. The manual-feed backing paper feeding device 44 is disposed on the upper surface of the backing paper stacking table 44a and the backing paper stacking table 44a, and a push-up plate 44b that is rotatably disposed by a hinge 44ax at the rear end of the backing paper stacking table 44a. Pickup roller 44c, paper feed roller 44d, paper roller 44e connected by lever 44j, guide plate 44f for guiding the back paper fed by paper feed roller 44d and paper feed roller 44e, and back on back paper stacking table 44a It comprises a sensor switch 44g for detecting the presence or absence of paper and a side regulating plate 44h provided on the backing paper stacking table 44a.

  The operation will be described. A bundle of backing paper R is stacked on the push-up plate 44b on the upper surface of the backing paper stacking table 44a. At this time, as shown in FIG. 2B and FIG. 2C, the side of the backing paper R on the backing paper stacking table 44a is regulated by the side regulating plate 44h. In addition to being irregular, the surface of the backing paper R is also wavy, that is, swelled as shown by the broken lines in FIGS. 2 (a) to 2 (c).

  When the control device (not shown) commands the feeding of the backing paper R, the lever 44j is lowered by a driving mechanism (not shown) to bring the pickup roller 44c into contact with the uppermost backing paper R on the push-up plate 44b. The pickup roller 44c, the paper feed roller 44d, and the separating roller 44e start rotating by a driving device (not shown), and the paper feed of the backing paper R is started.

  The push-up plate 44b, which is rotatably arranged by the hinge 44ax at the rear end of the backing paper stacking table 44a, is configured to turn around the hinge 44ax by a drive mechanism (not shown). When the backing paper R on the paper stacking table 44a decreases, the inclination angle of the push-up plate 44b increases, the contact between the uppermost backing paper R on the push-up plate 44b and the pickup roller 44c is maintained, and paper feeding continues. However, the rush angle of the fed backing paper R into the guide plate 44f becomes small as shown in FIG. For this reason, it is assumed that a reliable sheeting is ensured by using the auxiliary sheeting device 61 on the detour conveyance path 46 disposed on the downstream side of the manual sheet-feeding sheet feeding device 44 described later.

  When there is no manual sheet paper R on the back sheet stacking table 44a, it is detected by the sensor switch 44g, and a detection signal is sent to a control device (not shown) to indicate that the manual sheet paper R is empty.

  Next, the backing paper processing unit 60 provided on the detour conveyance path 46, which is a feature of the present invention, will be described. The backing paper processing unit 60 includes an auxiliary whispering device 61, a paper dust removing device 65, a swell detection sensor device 71, and a cleaner 75.

  FIG. 3 is a diagram for explaining the configuration of the auxiliary roller 61. The auxiliary roller 61 includes a paper feed roller 61a, a pickup roller 61b coupled by a lever 61f biased by a spring 61e, a solenoid 61d, and a paper feed roller 61a. And a roller 61c that is urged by a spring 61g, a guide plate 61h, a detection switch 61j, and the like.

  The operation will be described. When the backing paper R conveyed on the detour conveyance path 46 is detected by the detection switch 61j, the solenoid 61d is activated, and the pickup roller 61b at the standby position is lowered to the operating position and contacts the backing paper R. . The backing paper R fed by the pickup roller 61b is guided by the guide plate 61h and passes through the nip portion between the feeding roller 61a and the separating roller 61c, and the fed backing paper R is rolled up and separated one by one. Then, it is conveyed to the paper dust removing device 65 at the subsequent stage.

  Even if there is a backing paper R that has been transported by being transported over the bypass transport path 46 from the manual-feed backing paper feeder 44, a large number of the backing paper R that has been transported by being transported in a double feed is transported in a multiple manner. Since it is not conveyed, there is no need for a push-up plate or the like in the manual-feeding paper feeder 44, and the entry angle to the guide plate 61h is substantially constant, so that stable and reliable paper-making processing is executed. .

  As apparent from FIG. 1, the paper dust removing device 65 includes a brush roller 65a, a filter 65b, and an exhaust fan 65c. Paper dust, dust, etc. adhering to the front / back surface of the backing paper R are removed by the rotating brush roller 65a and the exhaust fan 65c, and conveyed to the subsequent swell detection sensor device 71.

  4A and 4B are diagrams for explaining the configuration of the swell detection sensor device 71. FIG. 4A is a front view thereof, and FIG. 4B is a side view as viewed from the conveyance direction of the recording paper. The swell detection sensor device 71 includes a swell detection lever 71M disposed at the center in the width direction of the backing paper R on the detour conveyance path 46, a swell detection lever 71P disposed at the right edge in the width direction of the backing paper R, and the back. The wave detection lever 71Q disposed at the left edge of the width direction of the paper R, the wave detection sensors 71Mx and 71My that detect the movement of the wave detection lever 71M, the wave detection sensors 71Px and 71Py that detect the movement of the wave detection lever 71P, And swell detection sensors 71Qx and 71Qy for detecting the motion of the swell detection lever 71Q.

  When the undulation of the backing paper R is small, the movement of the undulation detection levers 71M, 71P, 71Q is small, and detection signals are output only from the undulation detection sensors 71Mx, 71Px, 71Qx. In addition, when the undulation of the backing paper R is large, the movement of the undulation detection levers 71M, 71P, 71Q is large, and detection signals are output from the undulation detection sensors 71Mx, 71Px, 71Qx and the undulation detection sensors 71My, 71Py, 71Qy. The backing paper R that has passed through the swell detection sensor device 71 is conveyed to a subsequent cleaner 75.

  Further, by processing the detection signals of the swell detection sensors 71Mx, 71Px, 71Qx, 71My, 71Py, 71Qy, it is also possible to detect the backing paper R in which the corners of the paper have been broken. In addition to the undulation of the backing paper R, the quality of the backing paper can also be detected.

  The detection signal output from the undulation detection sensor device 71 is input to a control device (not shown), and the quality of the backing paper R is determined. 2 is conveyed to the paper feed cassette 43 or the waste paper stacker 42. That is, when the detection signal is output from any of the undulation detection sensors 71Mx, 71Px, 71Qx and there is no detection signal from any of the undulation detection sensors 71My, 71Py, 71Qy, the undulation of the backing paper R is small and can be used. It is determined.

  Further, when the detection signal is output from any of the undulation detection sensors 71Mx, 71Px, 71Qx and the detection signal is output from any of the undulation detection sensors 71My, 71Py, 71Qy, the undulation of the backing paper R is large. It is determined that it cannot be used.

  The cleaner 75 is composed of a pair of rollers, and is for cleaning the front surface / back surface of the backing paper R.

  Next, the operation of judging the quality of the backing paper R fed from the manual backing paper feeding device 44 and transporting it to the first paper feeding cassette 41, the second paper feeding cassette 43 or the waste paper stacker 42 will be described. To do.

  A command to convey from the control device (not shown) to the first paper feed cassette 41, the second paper feed cassette 43, or the waste paper stacker 42 according to the quality of the back paper R fed from the manual back paper feed device 44 Is output, the first switching guide 51 arranged at a portion where the normal conveyance path 45 and the detour conveyance path 46 branch is operated, and the conveyance path is moved from the normal conveyance path 45 toward the detour conveyance path 46. Switched. The backing paper R fed from the manual backing paper feeder 44 is transported from the normal transport path 45 to the detour transport path 46 via the first switching guide 51.

  First, in the auxiliary sheeting device 61 of the backing paper processing unit 60 on the detour conveyance path 46, the double-fed backing paper R is rolled and separated one by one. In the paper dust removing device 65, paper dust, dust and the like adhering to the front surface / back surface of the backing paper R are removed by a rotating brush roller 65a. In the undulation detection sensor device 71, the undulation of the backing paper R is detected. The output detection signal is input to a control device (not shown), and the quality of the backing paper R is determined. The backing paper R that has passed through the swell detection sensor device 71 is cleaned by the cleaner 75 on the front surface / back surface, and is transported toward the return transport path 48.

  The second switching guide 52 and the third switching guide 53 on the return conveyance path 48 are operated based on the determination result of the quality of the backing paper R based on the detection signal of the swell detection sensor device 71 input to the control device.

  That is, when it is determined that the quality of the backing paper R is sufficiently usable, the second switching guide 52 is operated and the first paper feed cassette 41 having a larger capacity than the other paper feed cassettes is operated from the return conveyance path 48. The paper path on the return conveyance path 48 is switched from the rear end of the first paper feed cassette 41 to the inside of the cassette.

  When the quality of the backing paper is insufficient but it is determined that it can be used for test printing or the like, the second switching guide 52 and the third switching guide 53 are set to the inoperative positions, and the second conveying guide 48 is set to the second from the return conveyance path 48. The transport path is switched to the paper feed cassette 43, and the backing paper on the return transport path 48 is transported from the rear end of the second paper feed cassette 43 into the cassette.

  When it is determined that the quality of the backing paper is unusable, the second switching guide 52 is set to the inoperative position, the third switching guide 53 is set to the operating position, and the waste paper stacker is returned from the return conveyance path 48. The transport path is switched to 42. The backing paper on the return conveyance path 48 is conveyed from the rear end of the waste paper stacker 42 to the inside thereof.

  Next, the configurations of the first and second paper feed cassettes and the waste paper stacker will be described. The first paper feed cassette 41 is configured to have a larger capacity than the second paper feed cassette 43. The basic configuration is the same as the first paper feed cassette 41 and the second paper feed cassette 43, and the waste paper stacker 42 is obtained by omitting the paper feed mechanism 40a from the first paper feed cassette 41. The configuration of the one paper feed cassette 41 will be described.

  FIG. 5 is a front cross-sectional view illustrating the configuration of the first paper feed cassette 41, and FIG. 6 is a plan view illustrating the configuration of the first paper feed cassette 41.

  The first paper feed cassette 41 includes a push-up plate 41b that is pushed up by a push-up lever 41a that is operated by a drive mechanism (not shown) on the bottom surface of the paper feed cassette, as in the conventional paper feed cassette, and is housed in the paper feed cassette. A width direction regulating plate 41d for regulating the width direction position of the back paper (same for recording paper) and a rear end regulating plate 41e for regulating the rear end position of the back paper (same for recording paper). The width direction restricting plate 41d and the rear end restricting plate 41e are adjusted according to the size of the back paper to be stored (the same applies to the recording paper) and are the same as those of the conventional paper feed cassette. Omitted.

  A paper feed mechanism 40a is arranged above the push-up plate 41b of the paper feed cassette. The paper feed mechanism 40a includes a paper feed roller 42a, a separation roller 42b, and others in addition to the pickup roller 41c.

  An insertion guide 41g is disposed above the rear end regulating plate 41e so as to face the terminal end of the return conveyance path 48. An insertion roller mechanism 41h is disposed on the insertion guide 41g. The insertion roller mechanism 41h includes an insertion roller 41j that is rotatably disposed at the tip of the swing lever 41f, an insertion roller 41m that is disposed opposite the conveyance roller 40y that is disposed at the exit of the return conveyance path 48, and an insertion roller. A mechanism actuating solenoid 41k and a return spring 41n are provided. When the swing lever 41f is operated by the inserting roller mechanism actuating solenoid 41k, the inserting roller 41j is configured to be movable between an operating position and a standby position.

  7 is a front cross-sectional view of the first paper feed cassette 41. FIG. 7A shows a state when the back paper R is fed, and FIG. 7B shows the storage of the back paper R conveyed from the return conveyance path 48. FIG. 7C shows a state at the time of detecting the storage state of the backing paper R. FIG. 8 is a plan view showing the vicinity of the arrangement of the first paper feed cassette 41, the push-up lever 41a, and the lift-up detection sensor 41w.

  With reference to FIG. 7A, the operation of feeding the backing paper R by the first paper feeding cassette 41 will be described. During paper feeding, the backing paper R stacked on the push-up plate 41b is pushed up by the push-up lever 41a and brought into contact with the pickup roller 41c, and is sent out by the rotation of the pickup roller 41c. Then, the uppermost one backing paper R stacked on the push-up plate 41b is fed toward the transport roller 40s through the paper feed roller 42a and the separation roller 42b.

  Next, the storing operation of the backing paper R conveyed through the return conveyance path 48 will be described with reference to FIGS. When the leading edge of the backing paper R conveyed from the return conveyance path 48 reaches the insertion guide 41g and is detected by a detection switch (not shown), the insertion roller mechanism operation solenoid 41k (see FIG. 5) of the insertion roller mechanism 41h is activated. Then, the insertion roller 41j that is normally in a standby position (a position that does not contact the backing paper R) is brought into contact with the conveyed backing paper R. The insertion roller 41j is driven by a drive source (not shown), and the backing paper R conveyed from the return conveyance path 48 is stored from the rear end of the first paper feed cassette 41. Note that the storage operation of the backing paper R is executed in a state where the push-up plate 41b is lowered.

  Next, with reference to FIG. 7C, a storage state detection device for the back paper in the paper feed cassette will be described. Here, the storage state detection device for the back paper R in the first paper feed cassette 41 will be described, but the same applies to the second paper feed cassette 43.

  The detection of the storage state of the backing paper includes detection of the state where the backing paper R is full in the paper feed cassette and detection of the remaining amount of backing paper. Note that these configurations are the same for other paper feed cassettes.

  First, detection of a state in which the backing paper R conveyed from the return conveyance path 48 is full in the first paper feed cassette 41 will be described.

  The detection of the state where the backing paper R is full is detected by a detection device including a detection lever 41v and a detection switch 41u arranged above the push-up plate 41b of the paper feed cassette. That is, the detection lever 41v gradually rotates in response to the storage of the backing paper R, and when the backing paper R becomes full, the detection switch 41u is turned on, and it is detected that the backing paper R is full.

  Next, detection of the remaining amount of the backing paper R will be described. The remaining amount of the backing paper R is detected from the amount of rotation of the roller arm 41t that holds the pickup roller 41c and the push-up lever 41a. That is, in the initial state, the push-up lever 41a turns off the lift-up detection sensor 41w, but as the backing paper R is fed, the push-up lever 41a gradually rotates to push up the push-up plate 41b and turn on the lift-up detection sensor 41w. And Further, when the push-up lever 41a rotates, the backing paper R on the push-up plate 41b comes into contact with the pickup roller 41c to be in a pressure contact state. This pressure contact state is detected when the roller arm 41t turns off the fixed position sensor 41x.

  The amount of rotation of the push-up lever 41a from the OFF state of the lift-up detection sensor 41w until the fixed position sensor 41x is turned off is detected by a sensor (not shown), and the remaining amount of the backing paper R can be detected.

  Next, a back paper alignment mechanism that aligns the back paper R in the paper feed cassette will be described. The paper feed cassette is provided with sensors for detecting the paper passing direction and the backing paper size in the direction perpendicular to the paper passing direction (backing paper width direction).

  FIG. 9 is a front sectional view for explaining the restriction plate (width direction restriction plate and rear end restriction plate) of the first paper feed cassette 41, and FIG. 10 is a plan view for explaining the restriction plate of the first paper feed cassette 41. . The first paper feed cassette 41 is provided with a width direction restricting plate 41d for restricting the position in the width direction of the stored backing paper R and a rear end restricting plate 41e for restricting the rear end of the stored backing paper R. ing. The width direction restricting plate 41d and the rear end restricting plate 41e are manually adjusted in accordance with the size of the backing paper R to be stored when the first paper feed cassette 41 is removed from the main body of the image forming apparatus 1. In addition, the position of the rear end regulating plate can be adjusted.

  At a position corresponding to the bottom surface of the sheet feeding cassette of the main body of the image forming apparatus 1, a width direction restricting plate driving mechanism 55, a rear end restricting plate driving mechanism 56, a sheet width direction sensor 55s, and a sheet rear end sensor 56s are arranged. The width direction regulating plate 41d and the rear end regulating plate 41e are configured to be driven to predetermined positions according to the size of the backing paper.

  When the first paper feed cassette 41 for storing the backing paper R is mounted on the main body of the image forming apparatus 1 and the size information of the backing paper R to be stored is input, the width direction regulating plate 41d and the trailing edge regulating plate 41e are Move to a position with a little margin than the predetermined position. When one sheet of the backing paper R conveyed from the return conveyance path 48 to the first sheet cassette 41 through the insertion guide 41g is conveyed, it is provided at a position corresponding to the bottom surface of the sheet cassette of the image forming apparatus main body. The width direction restricting plate drive mechanism 55 operates the width direction restricting plate 41d and the rear end restricting plate drive mechanism 56 operates the rear end restricting plate 41e to align the conveyed backing paper R at a predetermined position. .

  After the alignment operation, the width direction restricting plate 41d and the rear end restricting plate 41e are moved again to a position having a margin more than a predetermined position to prepare for receiving the backing paper R to be conveyed next. Thereafter, this operation is repeated every time one backing paper R is transported, and the alignment operation is continued until there is no transported backing paper R.

  As described above, the embodiment of the present invention has been described by taking the case where the backing paper R is reused as an example. However, the recycled paper can be used in the same manner instead of the backing paper R, and is used in the present invention. The paper is not limited to the backing paper R. In the case of recycled paper, paper dust or the like adheres to the recording paper, which may interfere with paper feeding. Since the paper feeding device of the present invention is equipped with a paper dust removing device, the recycled paper is not immediately loaded into the paper feeding cassette and fed, but once fed from the manual backside paper feeding device, the paper dust is removed. Then, it is preferable to select and feed a paper feed cassette storing the recycled paper.

  The present invention relates to a paper feeding device of an image forming apparatus such as a copying machine or a printer, and in particular, feeds the back side (back paper) of a recording paper on which an image is recorded from a manual paper feeding device for reuse. Only the back paper of good quality that can be tolerated is accommodated in the paper feed cassette, and the back paper of reduced quality that cannot withstand reuse is the paper feeding device of the image forming apparatus that is accommodated in the waste paper cassette.

1 is a front cross-sectional view illustrating an outline of a paper feeding device of an image forming apparatus according to an embodiment of the invention. 3A and 3B are diagrams illustrating a configuration of a manual reverse paper feed device. The figure explaining the structure of an auxiliary burning device. The figure explaining the structure of a wave | undulation detection sensor. FIG. 3 is a front cross-sectional view illustrating the configuration of a first paper feed cassette. The top view explaining the structure of the 1st paper feed cassette. The front view explaining the structure of a 1st paper feed cassette. The top view explaining operation | movement of a 1st paper feed cassette. FIG. 6 is a front cross-sectional view illustrating a restriction plate of a first paper feed cassette. The top view explaining the control board of a 1st paper feed cassette.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Image reading part 12 Document stand 13 Scanner 20 Image forming part 21 Photoconductor 22 Charging roller 23 Laser beam device 24 Developer 25 Transfer roller 26 Cleaning device 30 Fixing part 31 Fixing roller 32 Pressure roller 33 Fixing heater 40 Paper Feed Unit 40a Paper Feed Mechanism 40s Carry Roller 40y Carry Roller 41 First Paper Feed Cassette 42 Waste Paper Stacker 43 Second Paper Feed Cassette 44 Manual Back Paper Feeder 41a Push-up Lever 41b Push-up Plate 41c Pick-up Roller 41d Width Restriction Plate 41e Rear end regulating plate 41g Insertion guide 41h Insertion roller mechanism 41j Insertion roller 41k Insertion roller mechanism operation solenoid 42a Paper feed roller 42b Separation roller 44a Backing paper stacking table 44b Push-up plate 44c Pickup roller 44d Paper feed roller 44e Roller 44f guide plate 44g sensor switch 44h side regulating plate 44j lever 45 normal conveying path 46 detour conveying path 47 discharge conveying path 48 return conveying path 51 first switching guide 52 second switching guide 53 third switching guide 55 width direction regulating plate Drive mechanism 55s Paper width direction sensor 56 Rear edge regulating plate drive mechanism 56s Paper rear edge sensor 60 Back paper processing unit 61 Auxiliary paper roller 61a Paper feed roller 61b Pickup roller 61c Paper roller 61d Solenoid 61e, 61g Spring 61h Guide plate 61j Detection switch 65 Paper dust removing device 65a Brush roller 65b Filter 65c Exhaust fan 71 Waviness detection sensor device 71M, 71P, 71Q Waviness detection lever 71Mx, 71My, 71Px, 71Py, 71Qx, 71Qy Waviness detection sensor

Claims (5)

An image forming unit that forms an image on recording paper; and a plurality of paper feeding units including a manual paper feeding device that feeds the recording paper, and is formed from any one of the selected plurality of paper feeding units. In a paper feeding device of an image forming apparatus that feeds an image portion,
A detour conveyance path for determining whether or not the recording paper fed from the manual paper feeder is appropriate,
A return conveyance path for conveying the recording sheet conveyed from the detour conveyance path to a sheet feeding means other than the manual sheet feeding device;
A waste recording paper storage means for storing a waste recording paper not suitable for image recording;
When an unsuitable recording sheet is found on a recording sheet conveyed through the return conveyance path via the detour conveyance path, the image forming apparatus conveys the recording sheet as a disposal recording sheet to a disposal recording sheet storage unit. Paper feeder. The image forming apparatus according to claim 1, wherein the plurality of paper feeding units other than the manual paper feeding device are paper feeding units capable of storing recording paper conveyed from the return conveyance path. The paper feeder for the device. 2. The recording paper distortion detecting means for determining whether or not the use of the recording paper is appropriate is disposed on the detour conveyance path. Feeding device of the image forming apparatus. 2. The sheet feeding device of the image forming apparatus according to claim 1, wherein the plurality of sheet feeding units other than the manual sheet feeding device include a regulation plate for aligning the stored recording sheets. The paper feeding device of the image forming apparatus includes a paper feeding means for storing the recording paper or a waste recording according to a degree of distortion of the recording paper detected by the recording paper distortion detecting means arranged on the detour conveyance path. 2. A paper feeding device for an image forming apparatus according to claim 1, wherein a paper storage means is selected.

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