JP2005206274A - Paper feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder capable of easily carrying out jam processing of recording paper, even in a carrying passage for the recording paper horizontally traveling in an image forming device. <P>SOLUTION: A first carrying portion 41 is fixed to a frame 43, and a second carrying portion 42 is slidably supported by the frame 43. The frame 43 is slidably supported in the image forming device. By sliding of the frame 43 and the second carrying portion 42, any one of a first state that the first and second carrying portions 41, 42 are stored in the image forming device, a second state that the first carrying portion 41 alone is drawn out of the image forming device, and a third state that the first and second carrying portions 41, 42 are drawn out of the image forming device can be selectively set. Either one of a second or a third states is reported according to a collecting position of the recording paper, so that jam processing of the recording paper can be easily carried out. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a paper feeding device that conveys and supplies recording paper for image recording to an image forming apparatus.

  In recent years, in an image forming apparatus, since various types of optional units are selectively mounted while the apparatus is downsized, the mounting positions of the optional units are limited. For example, since the front surface of the image forming apparatus is used for user operations and the back side thereof is often approached to a wall surface or the like, optional units cannot be mounted on the front and back surfaces. Further, if a sheet post-processing function (such as stapling) and a sorter are mounted as an optional unit, one side of the image forming apparatus is occupied. Alternatively, if a paper feed cassette is mounted as an optional unit, the lower part of the image forming apparatus is occupied. Furthermore, if a recording paper manual feed mechanism and a large-capacity paper feed unit are mounted as optional units, the other side of the image forming apparatus is occupied.

  In such an image forming apparatus, the downsizing of the apparatus is implemented, the internal mechanism is densified, and the mounting position of the optional unit is limited. Therefore, it is necessary to set the recording paper conveyance path accordingly. For this reason, the conveyance path may extend long in the image forming apparatus. When the transport path is long, special measures are required to prevent the recording paper from being taken out when a jam occurs in which the recording paper is caught and stayed in the middle of the transport.

For example, Patent Document 1 includes a paper feed cassette disposed in the lower part of the image forming apparatus and a conveyance path for pulling out recording paper from the paper feed cassette and transporting it upward. A technique is disclosed in which the visibility of the conveyance path of the recording paper is improved and the jam processing is facilitated.
JP 2002-274675 A

  By the way, in the image forming apparatus, even if the recording paper is caught and stays in any part of the transport path, a plurality of parts of the transport path can be opened or the stay of the recording paper is detected so that the recording paper can be taken out. Are often displayed.

  However, if the conveyance path of the recording paper is long, even if the recording paper staying place is detected and displayed, it is not known which part of the conveyance path should be opened, and eventually many places are opened. In many cases, all of these points were inspected, and it took time to clear the jam.

  Accordingly, the present invention has been made in view of the above-described conventional problems, and provides a paper feeding device capable of quickly performing jam processing of recording paper even when the recording paper conveyance path is long. Objective.

  In order to solve the above-described problems, the present invention provides a paper feeding device that conveys and supplies recording paper for image recording to an image forming apparatus, is slidably supported with respect to the image forming apparatus, and is accommodated in the image forming apparatus. In this state, the conveying means for conveying the recording paper along the conveying path, the recording paper position detecting means for detecting the position of the recording paper on the conveying path, and the recording paper retained in the middle of the conveying path by the recording paper position detecting means And a notifying means for notifying the moving position of the conveying means from which the recording paper can be taken out based on the detected position of the recording paper.

  In the present invention, the conveying means is supported by the first and second conveying sections that sequentially convey the recording paper in the image forming apparatus, and is slidably supported with respect to the image forming apparatus, and the first and second conveying sections. And a frame for connecting and supporting the image forming apparatus so as to be able to contact and separate from each other, and the notifying means has a state in which only the first conveying section has moved out of the image forming apparatus as the moving position of the conveying means, and the first and second conveying sections Is informed of any of the states of having moved out of the image forming apparatus.

  Further, in the present invention, the state in which only the first transport unit is moved out of the image forming apparatus is set in order to remove the recording paper staying between the first and second transport units.

  In the present invention, the state in which the first and second transport units are moved out of the image forming apparatus is set in order to remove the recording paper staying in the second transport unit.

  Furthermore, in the present invention, the second transport unit forms a transport path for the recording paper between the upper guide and the lower guide, and supports the upper guide so that it can be opened and closed.

  In the present invention, the first transport unit forms a transport path for the recording paper between the first transport unit and an auxiliary guide provided on the image forming apparatus side, and the first transport unit is connected to the outside of the image forming apparatus. As the transport unit moves, the first transport unit and the auxiliary guide are separated from each other, and the transport path is opened.

  According to the present invention, when the position of the recording paper staying in the middle of the conveying path is detected by the recording paper position detecting means, the conveying means can take out the recording paper based on the detected position of the recording paper. The movement position of is notified. For this reason, if the conveying means is moved to the informed movement position, the recording paper can be taken out easily and quickly.

  The conveying unit is slidably supported with respect to the image forming apparatus and the first and second conveying units that sequentially convey the recording paper, and the first and second conveying units are connected and supported so as to be able to contact and separate from each other. And a frame. Then, the notifying unit is either a state in which only the first transport unit is moved out of the image forming apparatus or a state in which the first and second transport units are moved out of the image forming apparatus as the moving position of the transport unit. Is informed. For example, when the recording sheet is caught by the first conveyance unit, the state in which only the first conveyance unit has moved out of the image forming apparatus is notified, and when the recording sheet is caught by the second conveyance unit, A state in which the second transport unit has moved out of the image forming apparatus is notified. For this reason, regardless of which of the first and second transport sections the recording paper is caught in, the recording paper can be easily and quickly taken out by setting any state.

  The second transport unit forms a transport path for the recording paper between the upper guide and the lower guide, and supports the upper guide so that it can be opened and closed. Accordingly, the upper guide can be opened to open the transport path of the second transport section, and the recording paper caught on this transport path can be easily and quickly removed.

  Further, the first transport unit forms a transport path for the recording paper between the first transport unit and the auxiliary guide provided on the image forming apparatus side, so that the first transport unit moves outside the image forming apparatus. As a result, the first conveyance unit and the auxiliary guide are separated from each other, and the conveyance path is opened. For this reason, even if the recording paper is caught on the transport path, the transport path can be opened and the recording paper can be easily and quickly removed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a side view showing Embodiment 1 of the image forming apparatus of the present invention. 2 is an enlarged side view showing the main part of the image forming apparatus shown in FIG. The image forming apparatus of the present embodiment is a color laser printer that records a color image on a recording sheet, and includes an exposure unit 1, image forming stations Pa, Pb, Pc, Pd, an intermediate transfer belt unit 2, a fixing unit 3, and a sheet. A transport device 4 and a paper feeding device 5 are provided.

  In this image forming apparatus, recording sheets are respectively stacked and accommodated in a plurality of sheet feeding cassettes 6. In the paper transport device 4, the recording paper in one of the paper feed cassettes 6 is pulled out one by one by the pickup roller 7-1 and the recording paper is transported to the registration roller pair 8 by the transport roller pair 4-1.

  Alternatively, the recording paper is placed on the manual paper feed tray 9 or is stacked and accommodated in the large-capacity paper feed unit 10. In the paper feeder 5, the recording paper in the manual paper feed tray 9 is pulled out by the pickup roller 7-2, or the recording paper is received from the large-capacity paper feeding unit 10, and the recording paper is transferred to each conveying roller pair 4-7, 4 -8 to the registration roller pair 8 of the sheet conveying device 4.

  In the paper transport device 4, the recording paper is temporarily stopped by the pair of registration rollers 8, the front ends of the recording paper are aligned, and the front end of the recording paper is formed on the intermediate transfer belt 11 of the intermediate transfer belt unit 2. The recording sheet is conveyed to the secondary transfer roller 12 by the registration roller pair 8 at a timing overlapping with the registration roller 8.

  The image forming stations Pa, Pb, Pc, and Pd respectively form black (K), cyan (C), magenta (M), and yellow (Y) toner images, and transfer the toner images of the respective colors to the intermediate transfer belt unit. 2 is transferred to the intermediate transfer belt 11. These image forming stations Pa, Pb, Pc, and Pd include developing devices 21a to 21d, photosensitive drums 23a to 23d, chargers 24a to 24d, cleaner units 25a to 25d, and the like.

  Each of the photosensitive drums 23a to 23d is pressed by the primary transfer rollers 26a to 26d via the intermediate transfer belt 11, and has the same peripheral speed as that of the intermediate transfer belt 11 that rotates and moves in the arrow direction B. It is rotated together with the transfer belt 11. The primary transfer rollers 26 a to 26 d also rotate following the intermediate transfer belt 11 at the same peripheral speed as the intermediate transfer belt 11 that rotates and moves in the arrow direction B.

  Each of the chargers 24a to 24d is of a roller type, a brush type, or a charger type that is in contact with the photosensitive drums 23a to 23d, and uniformly charges the surfaces of the photosensitive drums 23a to 23d.

  The exposure unit 1 includes a laser light source (not shown) that emits a laser beam to each of the photosensitive drums 23a to 23d, a polygon mirror 1a that guides each laser beam to each of the photosensitive drums 23a to 23d, and a plurality of laser beams. Each of the photosensitive drums 23a to 23d is irradiated with each laser beam while modulating each laser beam according to the image data, and the surface of each photosensitive drum 23a to 23d is respectively provided. The electrostatic latent image is formed.

  The exposure unit 1 may be a writing head in which light emitting elements such as EL and LED are arranged in an array.

  Each of the developing devices 21a to 21d has a toner of each color, and attaches the toner of each color to the electrostatic latent image on the surface of each of the photoconductor drums 23a to 23d, so that each photoconductor drum 23a to 23d. A toner image of each color is formed on the surface. These toner images are transferred from the photosensitive drums 23a to 23d to the intermediate transfer belt 11 and superimposed.

  The intermediate transfer belt unit 2 includes an intermediate transfer belt 11, primary transfer rollers 26a to 26d, a driving support roller 31, driven support rollers 32, a secondary transfer roller 33, and the like, and drives the intermediate transfer belt 11. The primary transfer rollers 26 a to 26 d and the secondary transfer roller 33 are pressed against the intermediate transfer belt 11 by being supported by the support roller 31 and the driven support rollers 32 so as to be rotatable.

  The intermediate transfer belt 11 is formed of a synthetic resin film having a thickness of about 100 μm to 150 μm, for example. The secondary transfer roller 33 is supported so as to be movable left and right. When the secondary transfer roller 33 is moved rightward, the intermediate transfer belt 11 is sandwiched between the secondary transfer roller 33 and the drive support roller 31 to form a nip region. The drive support roller 31 functions as a backup roller for the secondary transfer roller 33, and rotates with the respective nip areas between the primary transfer rollers 26a to 26d and the photosensitive drums 23a to 23d downstream. When driven, the intermediate transfer belt 11 is pulled and rotated in the arrow direction B. Thereby, each nip area is stably maintained.

  In order to more stably form the nip areas between the primary transfer rollers 26a to 26d and the photosensitive drums 23a to 23d, the primary transfer rollers 26a to 26d and the photosensitive drums 23a to 23d are formed. Preferably, one of them is made of a hard material and the other is made of an elastic material.

  Each of the primary transfer rollers 26a to 26d is formed, for example, by coating the outer periphery of a metal shaft having a diameter of 8 mm to 10 mm with a conductive elastic material (EPDM, urethane foam, or the like). The primary transfer rollers 26a to 26d are opposite in polarity to the toner charging polarity in a state where the intermediate transfer belt 11 is sandwiched between nip regions between the primary transfer rollers 26a to 26d and the photosensitive drums 23a to 23d. Are applied to the toner on the surfaces of the photosensitive drums 23a to 23d via the intermediate transfer belt 11, and the toner on the surfaces of the photosensitive drums 23a to 23d is attracted to the intermediate transfer belt 11. To transcribe. As a result, the toner images of the respective colors are transferred to the intermediate transfer belt 11 and superimposed.

  In addition, as each primary transfer roller 26a-26d, you may use a brush etc. instead of a roller.

  The cleaning unit 34 is, for example, a cleaning blade that is in sliding contact with the surface of the intermediate transfer belt 11 and removes toner remaining on the surface of the intermediate transfer belt 11 to prevent fogging of an image to be printed next time.

  The toner images of the respective colors transferred and superimposed on the intermediate transfer belt 11 in this way are conveyed to the nip area between the drive support roller 31 and the secondary transfer roller 33 as the intermediate transfer belt 11 rotates. Then, the leading edge of each color toner image on the intermediate transfer belt 11 and the leading edge of the recording paper conveyed by the registration roller pair 8 are aligned, and the respective color toner images and the recording paper are overlapped to form each color toner image. Is transferred to the recording paper.

  Subsequently, the recording paper is conveyed to the fixing unit 3, where it is sandwiched between the pressure roller 3a and the heating roller 3b. As a result, the toner of each color on the recording paper is heated and melted and mixed, and the toner image of each color is fixed as a color image on the recording paper.

  Further, the recording paper is transported to the paper discharge tray 35 by the paper transport device 4 and discharged here face down.

  Note that it is also possible to form a monochrome image using only the image forming station Pa and transfer the monochrome image to the intermediate transfer belt 11 of the intermediate transfer belt unit 2. Similarly to the color image, this monochrome image is also transferred from the intermediate transfer belt 11 to the recording paper and fixed on the recording paper.

  When printing on both sides of the recording paper as well as on both sides, the image on the surface of the recording paper is fixed by the fixing unit 3, and then the recording paper is conveyed by the conveying roller pair 4-3 of the paper conveying device 4. In the middle, the conveying roller pair 4-3 is stopped and then reversely rotated, the recording paper is passed through the reversing path 4 r of the paper conveying device 4, the recording paper is turned upside down, and the recording paper is transferred to the registration roller pair 8. As in the case of the front surface of the recording paper, the image is recorded and fixed on the back surface of the recording paper, and the recording paper is discharged to the paper discharge tray 35.

  By the way, in such an image forming apparatus, recording sheets from the manual sheet feeding tray 9 and the large capacity sheet feeding unit 10 are conveyed from the right side to the left side of the image forming apparatus by the sheet feeding apparatus 5, and the image forming apparatus is moved in the horizontal direction. And then conveyed to the secondary transfer roller 12 through the registration roller pair 8. For this reason, if the recording paper is caught in the middle of conveyance by the paper feeding device 5, the recording paper stays in the image forming apparatus, and in this state, it is difficult to remove the recording paper.

  Therefore, in this embodiment, the paper feeding device 5 is divided and the paper feeding device 5 can be moved out of the image forming apparatus, thereby facilitating the removal of the recording paper. FIG. 3 is an enlarged side view showing the paper feeding device 5.

  As apparent from FIG. 3, the paper feeding device 5 includes a manual paper feed tray 9, a first transport unit 41, an auxiliary guide 41 </ b> A, a second transport unit 42, and a frame 43. The frame 43 is a frame that fixedly supports both sides of the first transport unit 41 and slidably supports both sides of the second transport unit 42. For example, the 2nd conveyance part 42 is arrange | positioned between a pair of rails (not shown) of the flame | frame 43, and the both edges of the 2nd conveyance part 42 are supported along each rail of the flame | frame 43 so that sliding is possible. By sliding the second transport unit 42 along the frame 43, the second transport unit 42 can be moved closer to or away from the first transport unit 41.

  The frame 43 is supported so as to be slidable in the horizontal direction between the exposure unit 1 in the image forming apparatus and the upper sheet cassette 6. For example, both edges of the frame 43 are slidably supported by a pair of rails in the image forming apparatus. By sliding the frame 43, the frame 43 can be pulled out of the image forming apparatus.

  The sliding direction of the frame 43 is a horizontal direction or a slightly upward direction. In addition, the sliding direction of the second transport unit 42 along the frame is also a horizontal direction or a slightly upward direction. Accordingly, the first and second transport units 41 and 42 slide in the horizontal direction or slightly upward to the right. Usually, as will be described later, when the manual paper feed tray 9 is pulled by hand and the frame 43 is slid out of the image forming apparatus, the manual paper feed tray 9 is slightly lifted and pulled. If the direction is horizontal or slightly upward, the slide operation of the frame 43 is facilitated. In addition, since the slide direction of the frame 43 is the horizontal direction or slightly upward to the right, the left end of the frame 43 does not rise upward during the slide of the frame 43, and the first and second transport units 41. , 42 does not contact the upper exposure unit 1. If the slide direction of the frame 43 is a downward direction, the slide operation of the frame 43 is uncomfortable, the left end of the frame 43 is raised upward, and the first and second transport units 41 and 42 are exposed. The unit 1 is contacted and an impact is applied to the exposure unit 1. Since the exposure unit 1 has a complicated optical path in which a polygon mirror and a plurality of mirrors are combined, if the exposure unit 1 receives an impact, the optical path is distorted and the quality of the recorded image is deteriorated.

  The manual feed tray 9 is pivotally supported by the lower end shaft 44 at the right end of the first transport unit 41, and one end of the connecting rod 45 is slidably fitted and supported by a side groove 9a. The other end of the connecting rod 45 is pivotally supported by a shaft 46 of the image forming apparatus main body. When the manual paper feed tray 9 is lifted in the arrow direction C, the manual paper feed tray 9 rotates around the shaft 44, one end of the connecting rod 45 moves to one end of the groove 9a, and the manual paper feed tray 9 moves to the image. It overlaps the side wall of the forming apparatus main body. Further, when the manual paper feed tray 9 is pushed down in the direction opposite to the arrow direction C, the manual paper feed tray 9 rotates and one end of the connecting rod 45 moves to the other end of the groove 9a and is caught. 9 is held in a slightly inclined state, and the manual paper feed tray 9 is opened. With the manual paper feed tray 9 opened, a recording paper is placed on the manual paper feed tray 9, and this recording paper is pulled out by the first transport unit 41.

  Instead of pivoting the manual sheet feed tray 9 on the right end of the first transport unit 41, the manual sheet feed tray 9 may be pivoted on the right end of the frame 43.

  The first transport unit 41 receives the recording paper from the manual paper feed tray 9 and transports it to the second transport unit 42, and receives the recording paper from the large-capacity paper feed unit 10 and receives the second transport unit 42. The lower conveyance path 52 is conveyed to the upper side, and the upper conveyance path 51 and the lower conveyance path 52 are merged on the second conveyance section 42 side. The auxiliary guide 41A is fixed to the image forming apparatus side, and forms a part of the lower conveyance path 52 between the auxiliary guide 41A and the lower side surface of the first conveyance unit 41.

  A pickup roller 7-2 and a separating plate 53 are arranged at the entrance of the upper conveyance path 51, and each conveyance roller pair 4-4, 4-5 is arranged along the upper conveyance path 51. The pickup roller 7-2 is pivotally supported by the shaft 54 of the support piece 53. The support piece 53 is pivotally supported by the main body of the first transport unit 41, and the pickup roller 7-2 is positioned at one of the positions P1 and P2 by the rotational movement of the support piece 53. The pickup roller 7-2 is separated from the separating plate 53 when positioned at the position P1, and is pressed against the separating plate 53 when positioned at the position P2. When the pickup roller 7-2 is rotationally driven in a state where the pickup roller 7-2 is in pressure contact with the separation plate 53, the recording paper on the opened manual paper feed tray 9 is moved to the pickup roller 7-2 and the separation plate. The sheets are separated one by one from among the sheets 53, and the recording paper is pulled out by the pickup roller 7-2. Then, the recording sheet is conveyed to the second conveyance unit 42 through the upper conveyance path 51 by the respective conveyance roller pairs 4-4 and 4-5.

  In the lower conveyance path 52, a conveyance roller pair 4-6 is arranged. The recording paper from the large-capacity paper feeding unit 10 enters from the entrance of the lower transport path 52 and is transported to the second transport section 42 through the lower transport path 52 by the transport roller pair 4-6. The upper roller and the lower roller of the conveying roller pair 4-6 are distributed and provided to the first conveying portion 41 and an auxiliary guide 41A fixed to the image forming apparatus side.

  A hook 55 is pivotally supported on the upper side of the first transport unit 41, and the tip of the hook 55 is biased downward by a spring (not shown). The hook 55 is connected to a lever (not shown) via a link mechanism (not shown), and the tip of the hook 55 is raised by the operation of the lever.

  The second transport unit 42 includes a transport path 56 that receives the recording paper from the first transport unit 41 and transports the recording paper to the registration roller pair 8.

  The junction 56 a of the conveyance path 56 faces the junction of the upper conveyance path 51 and the lower conveyance path 52 of the first conveyance unit 41. Further, on the conveyance path 56, the respective conveyance roller pairs 4-7 and 4-8 are arranged. The recording sheet is transported to the junction 56a of the transport path 56 through one of the upper transport path 51 and the lower transport path 52 of the first transport unit 41, and transported by the transport roller pairs 4-7 and 4-8. 56 is conveyed to the registration roller pair 8.

  The second transport unit 42 includes an upper guide 42-1 and a lower guide 42-2, and the left end of the upper guide 42-1 is pivotally supported by a shaft 57 of the lower guide 42-2. When the right end of the upper guide 42-1 is lifted, the upper guide 42-1 is opened and the transport path 56 is opened.

  In order to reliably convey the recording paper, the upper roller and the lower roller of each of the conveying roller pairs 4-4 to 4-8 are pressed against each other, and the recording paper is sandwiched between the upper roller and the lower roller. It is.

  FIG. 4 is a side view showing a drive system of the sheet feeding device 5. As shown in FIG. 4, the rotation of the drive shaft 61a of the drive motor 61 is transmitted to the shaft 4-8a of the lower roller of the conveying roller pair 4-8 through a gear unit 62 composed of a plurality of gears. The side roller is driven to rotate, and the upper roller of the conveying roller pair 4-8 is driven to rotate. Then, the rotation of the output shaft of the gear unit 62 is transmitted to the shaft 4-7a of the lower roller of the conveying roller pair 4-7 through the pulley unit 63 comprising a combination of a plurality of pulleys and a plurality of belts. The lower roller of 4-7 is driven to rotate, and the upper roller of the conveying roller pair 4-7 is driven to rotate. At the same time, the rotation of the output shaft of the pulley unit 63 is transmitted through the gear unit 64 to the upper roller shaft 4-6a of the transport roller pair 4-6 and the lower roller shaft 4-5a of the transport roller pair 4-5. These upper and lower rollers are driven to rotate, and the lower roller of the conveying roller pair 4-6 and the upper roller of the conveying roller pair 4-5 are driven to rotate. Further, the rotation of the output shaft of the gear unit 64 is transmitted through the gear unit 65 to the shaft 4-4a of the transport roller pair 4-4 and the shaft 7-2a of the pick-up roller 7-2, so that the transport roller pair 4-4 and the pick-up are picked up. The roller 7-2 is driven to rotate.

  In this way, the conveying roller pairs 4-4 to 4-8 and the pickup roller 7-2 are rotationally driven, and the recording paper is pulled out and conveyed.

  However, since the gear units 62, 64, 65 and the pulley unit 63 are dispersedly arranged in the image forming apparatus main body and the first and second transport units 41, 42, the frame 43 is slid from the inside of the image forming apparatus. When pulled out and the second transport unit 42 is slid along the frame 43 and separated from the first transport unit 41, the pulley unit 63 of the second transport unit 42 and the gear unit 64 of the first transport unit 41 are separated. The pair of transport rollers 4-4 to 4-6 and the pickup roller 7-2 of the first transport unit 41 are not driven to rotate. In addition, as shown in FIG. 6, when the frame 43 is further slid and pulled out from the inside of the image forming apparatus, and the second conveying unit 42 is further slid along the frame 43 and moved to the outside of the image forming apparatus, The unit 62 is separated in the middle, and the transport roller pairs 4-7 and 4-8 of the second transport unit 42 are not driven to rotate.

  On the other hand, in the image forming apparatus, optical paper sensors 71 and 72 are provided above the first and second transport units 41 and 42 of the paper feeding device 5, and the exit of the transport path 56 of the second transport unit 42. A mechanical paper sensor 73 is provided in the vicinity.

  The optical paper sensor 71 includes, for example, a light emitting element and a light receiving element, and irradiates light from the light emitting element to the upper conveyance path 51 and the lower conveyance path 52 through the opening portion of the first conveyance unit 41, and each of the conveyance paths 51, When the recording sheet is conveyed along the line 52, the light reflected by the recording sheet is incident on the light receiving element, and the presence or absence of the recording sheet in each of the conveying paths 51 and 52 is detected. Similarly, the optical paper sensor 72 includes, for example, a light emitting element and a light receiving element. Light that is reflected by the recording paper while being conveyed enters the light receiving element, and the presence or absence of the recording paper in the conveyance path 56 is detected.

  Further, the mechanical paper sensor 73 includes a movable piece 73a supported so as to be swingable, and a limit switch (not shown) that is turned on / off in accordance with the swing of the movable piece 73a. The swing of the movable piece 73a when contacting the recording sheet from the conveyance path 56 of the unit 43 is detected by a limit switch, and the presence or absence of the recording sheet in the vicinity of the exit of the conveyance path 56 is detected.

  Now, such a sheet feeding device 5 is normally set in a first state in which it is mounted in the image forming apparatus as shown in FIG. At this time, the frame 43 is disposed between the exposure unit 1 and the upper sheet cassette 6, and the first and second transport units 41 and 42 are accommodated in the image forming apparatus. Further, as shown in FIG. 8, the hook 55 of the first transport unit 41 is hooked on the convex portion 66 on the image forming apparatus side, and the convex portion 42 a of the second transport unit 42 is engaged with the concave portion 41 a of the first transport unit 41. The pin 42b at the tip of the second transport unit 42 is fitted into the hole 67 on the image forming apparatus side. In this state, the spring 41b in the concave portion 41a of the first conveyance portion 41 presses the convex portion 42a of the second conveyance portion 42, so that the pin 42b at the tip of the second conveyance portion 42 is in the hole 67 on the image forming apparatus side. The second conveyance unit 42 is positioned by being pressed. At the same time, the hook 55 of the first transport unit 41 pulls the convex portion 66 on the image forming apparatus side, and the first transport unit 41 is positioned. Further, the first and second transport units 41 and 42 are also positioned by being sandwiched inside the image forming apparatus main body.

  In this first state, the manual paper feed tray 9 is pushed down and opened, and the recording paper is placed on the manual paper feed tray 9. The recording paper is pulled out from the manual paper feed tray 9 by the pickup roller 7-2 of the first transport unit 41, and is transferred to the second transport unit 42 through the upper transport path 51 by the transport roller pairs 4-4 and 4-5. It is conveyed and conveyed to the registration roller pair 8 through the conveyance path 56 by the respective conveyance roller pairs 4-7 and 4-8 of the second conveyance section 42.

  Alternatively, the recording sheet is conveyed from the large capacity sheet feeding unit 10 to the first conveying unit 41. The recording sheet is guided to the lower conveyance path 52 of the first conveyance section 41 and conveyed to the second conveyance section 42 through the lower conveyance path 52 by the conveyance roller pair 4-6. Are conveyed to the registration roller pair 8 through the conveyance path 56 by the respective conveyance roller pairs 4-7 and 4-8.

  During the conveyance by the sheet feeding device 5 as described above, the recording sheet may be caught as described above, and the recording sheet may stay in the image forming apparatus. In this case, it is difficult to remove the recording paper in the first state.

  Therefore, first, as shown in FIG. 9, the tip of the hook 55 of the first transport unit 41 is lifted by the operation of a lever (not shown) to remove it from the convex portion 66 on the image forming apparatus side, and the manual feed tray 9 is manually moved. The frame 43 is slid out of the image forming apparatus. At this time, since the first transport unit 41 is fixedly supported by the frame 43, the first transport unit 41 follows the frame 43 and is slid out of the image forming apparatus and separated from the auxiliary guide 41A fixed to the image forming apparatus side. To do. Further, the upper roller and the lower roller of the pair of transport rollers 4-6 are separated from each other because the first transport unit 41 and the auxiliary guide 41A are provided separately. Thereby, the lower conveyance path 52 of the first conveyance unit 41 is opened. Further, since the second transport unit 42 is slidably supported by the frame 43 and is sandwiched and positioned inside the image forming apparatus main body, the second transport unit 42 does not follow the frame 43 and remains in the image forming apparatus. 43 is caught on one end. As a result, the sheet feeder 5 is set to the second state.

  In this second state, since the front and rear of the first transport unit 41 are opened, the recording paper staying in the upper transport path 51 of the first transport unit 41 can be easily removed, and the lower transport path 52 Therefore, the recording paper staying in the lower conveyance path 52 can be easily removed.

  Further, as shown in FIG. 10, the second transport unit 42 is pulled out by holding it, the second transport unit 42 is slid out of the image forming apparatus along the frame 43, and the second transport unit 42 is moved to the first transport unit. Approach part 41. As a result, the sheet feeder 5 is set to the third state.

  In this third state, as shown in FIG. 11, the upper guide 42-1 of the second transport unit 42 can be opened and the transport path 56 can be opened, so that it stays in the transport path 56 of the second transport unit 42. It is possible to easily remove the recording paper.

  Therefore, even if the recording paper stays in the long paper feeding device 5 that cuts the image forming apparatus substantially in the horizontal direction, the manual paper feeding tray 9 is pulled and the frame 43 is slid out of the image forming apparatus, so that the second state Or by further pulling out the second conveyance unit 42 and sliding the second conveyance unit 42 out of the image forming apparatus along the frame 43 to set the third state. If the guide 42-1 is opened, the recording paper can be easily jammed.

  Further, in this embodiment, when the recording paper stays in the paper feeding device 5, the recording paper staying position is detected by each of the optical paper sensors 71 and 72 and the mechanical paper sensor 73, and according to this staying position. Thus, either the second state or the third state is notified, and the jam processing is further facilitated. For example, when the recording paper stays in the first transport unit 41, a second state in which the recording paper staying in the first transport unit 41 can be easily removed is notified. Further, when the recording paper stays in the second transport unit 42, a third state in which the recording paper staying in the second transport unit 42 can be easily removed is notified. Therefore, if one of the notified second and third states is set, the jamming process of the recording paper can be performed quickly.

  FIG. 12 is a block diagram showing a circuit configuration for informing the first to third states. As shown in FIG. 12, the control unit 74 inputs detection outputs of the optical paper sensors 71 and 72 and the mechanical paper sensor 73. Based on the detection outputs of the sensors 71, 72 and 73, A recording paper staying time is counted for each position of the sensors 71, 72, 73, and when the recording paper staying time exceeds a certain level, the recording paper stays at the position of the sensor detecting the recording paper. Is determined. Then, the control unit 74 displays any one of the first to third states on the display unit 75 according to the position where the recording paper stays, and also displays the occurrence of the jam.

  For example, if it is determined that the recording paper is staying at the position of the sensor 71, the second state and the occurrence of jam are displayed on the display unit 75. When the recording paper stays at the position of the sensor 71, the recording paper stays in either the upper transport path 51 or the lower transport path 52 of the first transport unit 41, and in the second state. The jam treatment is preferable.

  Also, when it is determined that the recording paper is staying at the position of each sensor 71, 72, the second state and the occurrence of jam are displayed on the display unit 75. When the recording paper stays at the positions of the sensors 71 and 72, the recording paper stays between the first transport unit 41 and the second transport unit 42, and the jam processing in the second state is performed. preferable.

  Further, if it is determined that the recording paper is staying at the position of each sensor 72 or 73, the third state and the occurrence of jam are displayed on the display unit 75. When the recording paper stays at the position of each sensor 72 or 73, the recording paper stays in the second transport unit 42, and jamming in the third state is preferable.

  In addition to displaying the first to third states, notification may be made by voice or the like, or by display and voice.

  As described above, in the sheet feeding device 5, the first conveyance unit 41 is fixed to the frame 43, the second conveyance unit 42 is slidably supported by the frame 43, and the frame 43 is slidably supported in the image forming apparatus. In the first state in which the first and second transport units 41 and 42 are accommodated in the image forming apparatus, only the first transport unit 41 is pulled out of the image forming apparatus by sliding the frame 43 and the second transport unit 42. Since either the second state or the third state in which the first and second transport units 41 and 42 are pulled out of the image forming apparatus can be selectively set, jamming of the recording paper caught during the transport is possible. Can be easily performed.

  Further, since the upper transport path 51 and the lower transport path 52 are provided in the first transport unit 41, and the transport paths 51 and 52 are joined and connected to the transport path 56 of the second transport unit 42, a simple configuration However, paper can be fed from the manual paper feed tray 9 and the large-capacity paper feed unit 10 together.

  Further, instead of detecting the staying position of the recording sheet and notifying the staying position, either one of the second and third states is notified according to the staying position. It can be set and jammed immediately. If only the staying position is to be notified, the user cannot know whether the jam processing can be performed quickly if either the second or third state is set, and trial and error are necessary. The jam processing time becomes longer.

  In addition, this invention is not limited to the said Example, It can deform | transform variously. For example, although the upper conveyance path 51 and the lower conveyance path 52 are provided in the first conveyance unit 41, any one of the conveyance paths may be provided. Moreover, you may change arbitrarily the length of the 1st and 2nd conveyance parts 41 and 42. FIG.

  Further, the positioning mechanism of the first and second transport units 41 and 42 is not limited to the one shown in FIG. 8, and can be variously modified. For example, as shown in FIG. 13A, the hook 55 of the first transport unit 41 is hooked on the convex portion 66 on the image forming apparatus side, and the convex portion 41 c of the first transport unit 41 becomes the concave portion 42 c of the second transport unit 42. The pins 81, 81 of the first conveying unit 41 are fitted into the holes 82, 82 on the image forming apparatus side, and the pins 42 b at the tip of the second conveying unit 42 are fitted into the holes 67 on the image forming apparatus side. You may make it match. In this state, the spring 42d in the concave portion 42c of the second conveying portion 42 presses the convex portion 41c of the first conveying portion 41, so that the pin 42b at the tip of the second conveying portion 42 is in the hole 67 on the image forming apparatus side. The second conveyance unit 42 is positioned by being pressed. At the same time, the hook 55 of the first transport unit 41 pulls the convex portion 66 on the image forming apparatus side, and the pins 81 and 81 of the first transport unit 41 are vertically moved by the spring 83 (shown in FIG. 13B). The first conveying unit 41 is positioned by being pressed and pressed into the holes 82 and 82 on the image forming apparatus side.

  When the first and second transport units 41 and 42 are pulled out, the tip of the hook 55 of the first transport unit 41 is raised by operating a lever (not shown) as shown in FIG. The manual feed tray 9 is pulled by hand, the pins 81, 81 of the first transport unit 41 are removed from the holes 82, 82, and the frame 43 (not shown) is removed. ) Is slid out of the image forming apparatus.

  Further, as shown in FIG. 14A, the two hooks 86, 86 of the first transport unit 41 are hooked on the convex portions 85, 85 on the image forming apparatus side, and the pin 42b at the tip of the second transport unit 42 forms the image. The first and second transport units 41 and 42 may be positioned in a state of being fitted in the hole 67 on the apparatus side. The hooks 86 and 86 are pivotally supported on the side wall of the first transport unit 41, their tips are biased downward by a spring (not shown), are connected to each other via a link mechanism 87, and are linked. It is also connected to a lever (not shown) via a mechanism (not shown).

  When the first and second transport units 41 and 42 are pulled out, the tips of the hooks 86 and 86 of the first transport unit 41 are raised by operating a lever (not shown) as shown in FIG. It is removed from the respective convex portions 85, 85 on the image forming apparatus side, the manual paper feed tray 9 is pulled by the hand, and the frame 43 (not shown) is slid out of the image forming apparatus.

1 is a side view showing Embodiment 1 of an image forming apparatus of the present invention. FIG. 2 is an enlarged side view showing a main part of the image forming apparatus in FIG. 1. FIG. 2 is an enlarged side view showing a paper feeding device in the image forming apparatus of FIG. 1. FIG. 4 is a side view showing a drive system of the sheet feeding device of FIG. 3. It is a side view which shows the other state of the drive system of FIG. It is a side view which shows another state of the drive system of FIG. FIG. 4 is a side view showing a state in which the first and second transport units of the paper feeding device of FIG. 3 are accommodated. FIG. 4 is a side view illustrating a positioning mechanism of first and second transport units of the paper feeding device of FIG. 3. FIG. 4 is a side view illustrating a state in which a first transport unit of the sheet feeding device illustrated in FIG. 3 is pulled out. FIG. 4 is a side view illustrating a state in which a second transport unit of the paper feeding device in FIG. 3 is pulled out. FIG. 4 is a side view showing a state where the second transport unit of the paper feeding device of FIG. 3 is pulled out and opened. FIG. 4 is a block diagram illustrating a circuit configuration of the sheet feeding device in FIG. 3. (A) is a side view which shows the modification of the positioning mechanism of a 1st and 2nd conveyance part, (b) is a side view which shows the state which pulled out the 1st conveyance part. (A) is a side view which shows the other modification of the positioning mechanism of a 1st and 2nd conveyance part, (b) is a side view which shows the state which pulled out the 1st conveyance part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exposure unit 2 Intermediate transfer belt unit 3 Fixing unit 4 Paper conveyance device 5 Paper feed device 6 Paper feed cassette 7-1, 7-2 Pickup roller 8 Registration roller pair 9 Manual feed tray 10 Large capacity paper feed unit 21, 21a -21d Developing device 23, 23a-23d Photosensitive drums 24a-24d Chargers 25a-25d Cleaner unit 41 First transport unit 42 Second transport unit 43 Frames 71, 72 Optical paper sensor 73 Mechanical paper sensor 74 Control unit 75 Display unit Pa, Pb, Pc, Pd Image forming station

Claims (6)

In a paper feeding device that conveys and supplies recording paper for image recording to an image forming apparatus,
A conveying unit that is slidably supported with respect to the image forming apparatus and that conveys the recording paper along the conveying path in a state of being accommodated in the image forming apparatus;
Recording paper position detecting means for detecting the position of the recording paper on the conveyance path;
When the position of the recording paper staying in the middle of the conveyance path is detected by the recording paper position detection means, the moving position of the conveyance means from which the recording paper can be taken out is notified based on the detected position of the recording paper. And a notifying unit. The conveying unit is supported so as to be slidable with respect to the image forming apparatus and the first and second conveying units that sequentially convey the recording paper in the image forming apparatus, and the first and second conveying units can be brought into contact with and separated from each other. A frame that supports connection,
The notifying means notifies the moving position of the conveying means of either the state in which only the first conveying unit has moved out of the image forming apparatus or the state in which the first and second conveying units have moved out of the image forming apparatus. The sheet feeding device according to claim 1, wherein:   3. The sheet feeding device according to claim 2, wherein the state in which only the first conveyance unit moves to the outside of the image forming apparatus is set to remove the recording paper staying between the first and second conveyance units. Paper device.   3. The sheet feeding device according to claim 2, wherein the state in which the first and second transport units are moved out of the image forming apparatus is set in order to remove the recording paper staying in the second transport unit. .   The sheet feeding device according to claim 2, wherein the second transport unit forms a transport path for the recording sheet between the upper guide and the lower guide, and supports the upper guide to be openable and closable.   The first conveyance unit forms a conveyance path for the recording paper between the first conveyance unit and an auxiliary guide provided on the image forming apparatus side. With the movement of the first conveyance unit to the outside of the image forming apparatus, The sheet feeding device according to claim 1, wherein the first conveyance unit and the auxiliary guide are separated from each other to open the conveyance path.

Images