JP2015083506A - Image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image formation device capable of improving the jam processing ability of a feeding part.SOLUTION: An image formation device 100 includes: a device body 1; a paper cassette 5; a pickup roller 7a which feeds a recording medium from the paper cassette 5; a feed roller 7b; a retard roller 7c; a holding member 10 which holds the retard roller 7c and causes the retard roller 7c to be placed in pressure contact with or separated from the feed roller 7b; a cover member 8 which is disposed at one side surface of the device body 1 and may open and close; and a lever member 11 which rotates in conjunction with opening operation of the cover member 8 and thereby engages with the holding member 10 so that a nip between the feed roller 7b and the retard roller 7c is released.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus including a feeding unit (a pickup roller, a feed roller, a retard roller) that feeds a recording medium from a recording medium storage cassette.

  2. Description of the Related Art Conventionally, there has been known an image forming apparatus including a sheet feeding unit (feeding unit) that feeds a sheet from a sheet feeding cassette (recording medium storing cassette) that stores sheet-like sheets (recording medium). The paper feed unit includes a pickup roller that feeds paper, a feed roller that transports the paper fed from the pickup roller, and a retard roller that presses against the feed roller to form a nip portion.

  In such an image forming apparatus, when a paper jam occurs in the paper feeding unit, usually, the paper feeding cassette is pulled out, the nip between the feed roller and the retard roller is released, and the paper is removed from the paper feeding unit. There is also known a configuration in which the nip of the paper feeding unit is automatically released when the paper feeding cassette is pulled out.

  However, in the conventional image forming apparatus, it is necessary to pull out the paper feed cassette and put the hand into the opening portion to remove the paper, so that it is difficult to improve the jam handling performance. Even if the nip of the paper feeding unit is automatically released when the paper feeding cassette is pulled out, when paper remains in the paper feeding unit, the paper feeding cassette is pulled out in the direction perpendicular to the paper feeding direction. The paper may be damaged.

  Therefore, an image forming apparatus is also known in which a cover member that can be opened and closed with respect to the apparatus main body is provided adjacent to the side of the sheet feeding unit. In this structure, the jam processing can be performed from the side surface of the apparatus main body by opening the cover member.

  An image forming apparatus capable of releasing the nip of the paper feeding unit is disclosed in, for example, Patent Documents 1 and 2.

JP-A-8-151165 JP-A-10-167502

  However, in the structure in which the cover member is simply provided on the side surface of the apparatus main body, since the paper is nipped by the paper feeding unit, it is easily damaged when the paper is removed, and it is difficult to improve the jam handling performance. There is a problem.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of improving the jam handling performance of a feeding unit.

  In order to achieve the above object, an image forming apparatus of the present invention includes an apparatus main body, a recording medium storage cassette that is attached to the apparatus main body and stores a recording medium, a pickup roller that feeds the recording medium from the recording medium storage cassette, A feed roller that conveys the recording medium fed from the pickup roller, a retard roller that presses against the feed roller to form a nip portion, a holding member that holds the retard roller and presses or separates from the feed roller, and a holding member And a biasing member that presses the retard roller against the feed roller to form a nip pressure, and is disposed on one side of the apparatus main body, adjacent to the downstream side of the feed roller in the recording medium conveyance direction. By opening and closing the cover member and rotating in conjunction with the opening operation of the cover member It comprises a lever member that engages the retaining member to release the nip between the feed roller and the retard roller, the.

  According to the present invention, the lever member engaged with the holding member is provided so as to release the nip between the feed roller and the retard roller by rotating in conjunction with the opening operation of the cover member. Thereby, when a jam of the recording medium occurs at the nip portion between the feed roller and the retard roller, the nip can be automatically released by opening the cover member. For this reason, it is possible to prevent the recording medium from being damaged and to improve the jam handling property.

1 is a perspective view illustrating a structure of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a structure around a sheet feeding unit of the image forming apparatus according to the embodiment of the present disclosure. FIG. 2 is a perspective view illustrating a structure around a sheet feeding unit of an image forming apparatus according to an embodiment of the present invention, and a perspective view illustrating an internal structure of a lower right portion of FIG. FIG. 3 is a bottom view illustrating the structure of a sheet feeding unit and a holding member of the image forming apparatus according to the embodiment of the present invention. 5 is a perspective view showing the structure around the lever member of the image forming apparatus according to the embodiment of the present invention from the lower side, and is a perspective view showing the structure of the left side (the back side of the apparatus) in FIGS. is there. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3 with the cover member of the image forming apparatus according to the embodiment of the present invention closed. FIG. 4 is a cross-sectional view showing a state where the cover member of the image forming apparatus according to the embodiment of the present invention is opened along the line AA in FIG. 3. It is the elements on larger scale of FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  An image forming apparatus 100 according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the image forming apparatus 100 includes an apparatus main body 1 and an image reading apparatus 2 disposed on an upper part thereof.

  In the image reading device 2, an image reading unit for reading image information of a document on the contact glass 2a is provided. The image reading unit includes a scanner lamp that illuminates the document during copying, a scanning optical system equipped with a mirror that changes the optical path of reflected light from the document, a condensing lens that focuses the reflected light from the document, And a CCD sensor or the like (not shown) that converts the imaged image light into an electrical signal, and reads a document image and converts it into image data.

  An operation panel 3 having operation buttons and a display unit is provided on the front portion of the image reading apparatus 2. A platen (not shown) that presses the document placed on the contact glass 2a is provided on the upper part of the image reading device 2 so as to be opened and closed. On the platen, an automatic document feeder (not shown) may be provided that automatically and sequentially feeds one document at a time from the document bundle onto the contact glass 2a.

  Between the image reading apparatus 2 and the apparatus main body 1, an in-body discharge space 4 is provided that is largely open toward the left side and the front.

  A plurality (two in this case) of paper feed cassettes (recording medium storage cassettes) 5 for storing sheets (recording media) are detachably provided on the front surface of the apparatus body 1. The attachment / detachment direction of the paper feed cassette 5 with respect to the apparatus main body 1 is orthogonal to the paper conveyance direction (recording medium conveyance direction) from the paper supply cassette 5.

  Inside the apparatus main body 1, there are provided an image forming unit, a fixing unit, a paper transport path 6 (see FIG. 2) and the like (not shown). The image forming unit forms an image by transferring a toner image onto a supplied sheet based on image data read by the image reading device 2. The image forming unit includes a photosensitive drum that carries an electrostatic latent image, a charging unit that charges the surface of the photosensitive drum, and an exposure that forms an electrostatic latent image corresponding to a document image on the surface of the photosensitive drum with a laser beam or the like. Unit, a developing unit for forming a toner image by attaching a developer to the formed electrostatic latent image, a transfer roller for transferring the toner image to a sheet, a cleaning blade for removing residual toner on the surface of the photosensitive drum, and the like. Yes. The fixing unit fixes the toner image on the paper by heating and pressurizing the paper on which the toner image is transferred. The sheet conveyance path 6 (see FIG. 2) extends upward along the right side surface of the apparatus main body 1 and conveys the sheet from the sheet feeding cassette 5 to the image forming unit.

  Further, as shown in FIG. 2, at the lower right side inside the apparatus main body 1, a sheet feeding section (feeding section) 7 for feeding sheets from the sheet feeding cassette 5 and one side surface (right side face) of the apparatus main body 1 are provided. An openable / closable cover member 8 is provided adjacent to the right side (downstream side in the sheet conveying direction) of the sheet feeding unit 7.

  One sheet feeder 7 is provided for each sheet cassette 5, and two sheet feeders 7 are provided in this embodiment. The sheet feeding unit 7 conveys the sheet to the sheet conveyance path 6 disposed on the upper right side.

  The cover member 8 is configured to be swingable about a fulcrum (not shown) provided below the side surface of the apparatus main body 1. The cover member 8 is provided with a contact portion 8a (see FIG. 6) on which a lever member 11 described later is contacted.

  The paper feed unit 7 includes a pickup roller 7a that feeds paper from the paper feed cassette 5, a feed roller 7b that transports paper fed from the pickup roller 7a, and a retard roller 7c that presses against the feed roller 7b to form a nip portion. And. By feeding the pickup roller 7a while being pressed against the paper, the paper feeding is started. When a plurality of sheets are fed simultaneously by the pickup roller 7a, the sheet is picked up by the feed roller 7b and the retard roller 7c, and only the uppermost sheet is conveyed toward the sheet conveying path 6.

  The pickup roller 7a and the feed roller 7b are rotatably held in the housing 9 as shown in FIGS. 2 and 3, and the retard roller 7c is attached to the housing 9 as shown in FIGS. The holding member 10 is rotatably held. The holding member 10 is urged in a direction (upward) from the retard roller 7c toward the feed roller 7b by an urging member 14 (see FIGS. 4 and 5) formed of a tension coil spring. Specifically, the urging member 14 rotates a nip control lever (nip release member) 13 (see FIGS. 2 and 4) in a predetermined direction. The nip control lever 13 urges the holding member 10 upward. Thereby, the retard roller 7c is pressed against the feed roller 7b with a predetermined pressing force.

  Further, as shown in FIG. 5, an attachment shaft 9 a to which the lever member 11 is rotatably attached is provided on the back side of the apparatus of the housing 9 (left side in FIGS. 3 and 4). The mounting shaft 9a and the lever member 11 are disposed outside the paper passage area. A torsion coil spring 12 that urges the lever member 11 in the second direction (the clockwise direction in FIGS. 6 and 7) is attached to the rotation shaft (attachment shaft 9 a) of the lever member 11. The urging force of the torsion coil spring 12 against the lever member 11 is larger than the pressing force of the retard roller 7c against the feed roller 7b by the urging member 14. 6 to 8 show the state seen from the back side of FIGS. 2, 3 and 5, and the arrangement of each member is reversed to the left and right of FIG. 2, FIG. 3 and FIG. .

  The lever member 11 has an abutment piece 11a that abuts against the abutment portion 8a of the cover member 8 with the cover member 8 closed as shown in FIG. 6, and the cover member 8 that opens as shown in FIG. And a pressing piece 11b that engages with the engaging protrusion 10a of the holding member 10 in a state.

  Accordingly, as shown in FIG. 6, when the cover member 8 is closed, the contact portion 8a of the cover member 8 contacts the contact piece 11a of the lever member 11, and the lever member 11 moves in the first direction (the opposite direction of FIG. 6). Rotate clockwise. Then, the engagement between the pressing piece 11b and the engaging protrusion 10a of the holding member 10 is released. Thereby, the holding member 10 moves to the feed roller 7b side by the urging force of the urging member 14, and the retard roller 7c is pressed against the feed roller 7b with a predetermined pressing force.

  On the other hand, as shown in FIGS. 7 and 8, when the cover member 8 is opened, the cover member 8 is separated from the lever member 11, and the lever member 11 is moved in the second direction (first direction and the first direction by the urging force of the torsion coil spring 12. Rotate in the opposite direction. Then, the pressing piece 11b of the lever member 11 presses the engaging protrusion 10a of the holding member 10 in a direction (downward) away from the feed roller 7b. Thereby, the nip between the retard roller 7c and the feed roller 7b is released. The holding member 10 rotates about the rotation center 10b, and the retard roller 7c is pressed against or separated from the feed roller 7b about the rotation center 10b of the holding member 10.

  Moreover, the retard roller 7c is connected to the drive shaft 17 via the retard shaft 15 and the universal joint 16 as shown in FIG. For this reason, even if the retard roller 7c rotates about the rotation center 10b, the retard roller 7c can be driven (rotated) by the drive shaft 17.

  The nip control lever 13 is configured to release the nip between the retard roller 7c and the feed roller 7b in conjunction with the drawing operation of the paper feed cassette 5. The nip control lever 13 can be a rotating member that rotates via a link mechanism in conjunction with, for example, gripping the grip portion 5a (see FIG. 1) of the paper feed cassette 5. When the grip portion 5a is gripped by the operator, the nip control lever 13 is rotated, and one end of the nip control lever 13 is engaged with the holding member 10, whereby the holding member 10 is separated from the feed roller 7b. The nip between the retard roller 7c and the feed roller 7b may be released by moving in the direction (downward). Alternatively, the nip control lever 13 can be a lever member that is configured in the same manner as the relationship between the cover member 8 and the lever member 11, for example, and rotates according to the attachment / detachment operation of the paper feed cassette 5. When the nip control lever 13 is engaged with the holding member 10 in conjunction with the pulling-out operation of the paper feed cassette 5, the holding member 10 moves in a direction away from the feed roller 7b, and the retard roller 7c and the feed roller 7c are fed. The nip with the roller 7b may be released.

  In this image forming apparatus 100, when a jam occurs in the paper feeding unit 7, the cover member 8 is opened by the operator as shown in FIG. Then, in conjunction with the opening of the cover member 8 by the operator, the nip between the retard roller 7c and the feed roller 7b is released. At this time, if a jam has occurred in the paper feeding unit 7, the paper P is removed from the side surface (portion where the cover member 8 is opened) of the apparatus body 1 by the operator. Thereafter, after the jam processing is performed by the operator, a nip between the retard roller 7c and the feed roller 7b is formed in conjunction with the closing of the cover member 8.

  In the present embodiment, as described above, the lever member that engages with the holding member 10 to release the nip between the feed roller 7b and the retard roller 7c by rotating in conjunction with the opening operation of the cover member 8 as described above. 11 is provided. Accordingly, when a paper jam occurs at the nip portion between the feed roller 7b and the retard roller 7c, the nip can be automatically released by opening the cover member 8. For this reason, it is possible to prevent the paper from being damaged, and to improve the jam handling performance.

  Further, as described above, when the cover member 8 is closed, the cover member 8 contacts the lever member 11 and the lever member 11 rotates in the first direction, whereby the lever member 11 and the holding member 10 are engaged. Is released, and the holding member 10 is rotated by the biasing member 14 to form a nip, and the cover member 8 is separated from the lever member 11 by the opening operation of the cover member 8, and the lever member 11 is moved in the second direction. When the lever member 11 is engaged with the holding member 10 and the holding member 10 is rotated by the lever member 11, the nip is released. Accordingly, the nip can be easily formed in conjunction with the closing operation of the cover member 8, and the nip can be easily released in conjunction with the opening operation of the cover member 8.

  Further, when the lever member 11 is rotated in the first direction by the closing operation of the cover member 8, a gap is formed between the lever member 11 and the holding member 10 (the relationship between the lever member 11 and the holding member 10). Will be released). As a result, the lever member 11 can be prevented from coming into contact with the holding member 10 in a state where the cover member 8 is closed, so that the lever member 11 can be prevented from pressing the holding member 10 and releasing the nip. can do.

  Further, as described above, the urging force of the torsion coil spring 12 against the lever member 11 is larger than the pressing force of the retard roller 7c against the feed roller 7b. Thereby, when the lever member 11 presses the holding member 10, the retard roller 7c can be easily separated from the feed roller 7b.

  Further, as described above, the above-described nip control lever 13 that engages with the holding member 10 may be provided so as to release the nip in conjunction with the pulling-out operation of the paper feed cassette 5. In this case, it is possible to improve the jam handling performance when the paper feeding cassette 5 is pulled out to perform the jam handling. Such a configuration is particularly effective when the attachment / detachment direction of the paper feed cassette 5 with respect to the apparatus main body 1 is orthogonal to the paper transport direction (recording medium transport direction) of the paper feed cassette 5.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above-described embodiment, the example in which the lever member 11 presses the holding member 10 in conjunction with the opening operation of the cover member 8 has been described, but the present invention is not limited to this, and the operation is performed in conjunction with the opening operation of the cover member 8. The lever member 11 may be engaged so as to pull the holding member 10.

  In the above embodiment, the example in which the attachment / detachment direction of the paper feed cassette 5 with respect to the apparatus main body 1 is orthogonal to the paper transport direction is shown, but the present invention is not limited to this, and the attachment / detachment direction with respect to the apparatus main body 1 is paper. The present invention can also be applied to a paper feed cassette parallel to the transport direction. That is, the present invention can also be applied when the paper feed cassette 5 is attached and detached in the left-right direction (parallel to the paper transport direction) in FIG.

1 Device body 5 Paper feed cassette (recording medium storage cassette)
7a Pickup roller 7b Feed roller 7c Retard roller 8 Cover member 9a Mounting shaft (rotating shaft)
10 holding member 11 lever member 12 torsion coil spring 13 nip control lever (nip releasing member)
14 Biasing member 100 Image forming apparatus

Claims (4)

The device body;
A recording medium storage cassette mounted on the apparatus main body and storing a recording medium;
A pickup roller for feeding out the recording medium from the recording medium storage cassette;
A feed roller for conveying the recording medium fed from the pickup roller;
A retard roller that presses against the feed roller to form a nip portion;
A holding member that holds the retard roller and presses or separates it from the feed roller;
A biasing member that presses the retard roller against the feed roller to form a nip pressure by biasing the holding member;
An openable / closable cover member disposed adjacent to one side of the apparatus main body on the downstream side in the recording medium conveyance direction of the feed roller;
A lever member that engages with the holding member so as to release a nip between the feed roller and the retard roller by rotating in conjunction with the opening operation of the cover member;
An image forming apparatus comprising: When the cover member closes, the cover member comes into contact with the lever member, and the lever member rotates in the first direction, so that the engagement between the lever member and the holding member is released, and the biasing force is applied. By rotating the holding member by a member, the nip is formed,
The cover member is separated from the lever member by the opening operation of the cover member, and the lever member rotates in a second direction opposite to the first direction, whereby the lever member is engaged with the holding member. The image forming apparatus according to claim 1, wherein the nip is released when the holding member is rotated by the lever member. A torsion coil spring for urging the lever member in the second direction is provided on the rotation shaft of the lever member,
The image forming apparatus according to claim 1, wherein an urging force of the torsion coil spring against the lever member is larger than a pressing force of the retard roller against the feed roller.   The image according to any one of claims 1 to 3, further comprising a nip releasing member that engages with the holding member so as to release the nip in conjunction with a pulling operation of the recording medium storage cassette. Forming equipment.