JP2009126648A - Paper feeding device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeding device of simple structure comprising a paper feeding tray lock mechanism and a bottom plate push-up mechanism with a small number of parts, and to provide an image forming device with the same. <P>SOLUTION: A coupling member 56 is formed with a cylindrical recessed hole 56a, into which an end 85b of a rotating rod 85 can be inserted, in a central part thereof. The coupling member has an insertion groove 56d connected to the recessed hole 56a and radially extended from the center shaft of a rotary output shaft 58 in parallel with the rotary output shaft 58 to the bottom 56e of the recessed hole 56 inside of a free end 56c and formed with four notches having a width larger than the diameter of engagement protrusions 87a and 87b, into which the engagement protrusions 87a and 87b can be inserted, in the peripheral wall 56b. Further, the peripheral wall 56b of a terminal end 56d1 of the insertion groove 56d is formed with an engagement groove 56f, which is connected to the insertion groove 56d and which is formed of a notch having a diameter larger than the diameter of the engagement protrusions 87a and 87b, in the circumferential direction of the coupling member 56. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet feeding device having a sheet feeding tray that is detachably mounted on an apparatus main body, and an image forming apparatus such as a copying machine, a facsimile, and a printer including the sheet feeding tray.

In recent years, copying machines, printing apparatuses, printers, and the like have been required to reduce each operation force as accessibility support that can be easily operated by the elderly and the disabled due to consideration for the elderly and the disabled. There are similar demands regarding the setting force and pull-out force of the paper feed tray. Currently, the mainstream paper feed tray lock system is equipped with a bearing attached to the guide section that guides the paper feed tray in the direction of storage of the paper feed tray. A system is adopted in which the paper tray can be smoothly pulled out and stored, and the paper feed tray is pulled in the storage direction by a spring or the like.
In such a system, there is provided a lock means for preventing the movement of the paper feed tray in the pull-out direction so that the paper feed tray does not easily jump out due to vibration or impact, and at the same time the paper feed tray is set by this lock means. It has been proposed to lock the paper feed tray and unlock the locking means by a switch on the touch panel of the image forming apparatus. (For example, see Patent Document 1)

A sheet feeding device provided in the image forming apparatus is generally configured so that sheets stacked on the bottom plate of the sheet feeding tray can be fed one by one from the uppermost one. Then, in order to feed the sheets stacked on the bottom plate of the sheet feeding tray one by one from the uppermost one to the image forming unit, a feeding means such as a sheet feeding roller attached above the sheet feeding tray is used. It is necessary to bring the paper to be fed into contact. For this purpose, the entire bottom plate on which the paper in the paper feed tray is stacked can be moved up and down with the whole paper kept horizontal, and the front end of the paper in the feeding direction according to the remaining amount of the loaded paper. A system in which the bottom plate can be moved by tilting the tip of the bottom plate so that it can move up and down so that the sheet angle can be changed to a position where the sheet can be fed by a paper feed roller disposed above and raised. Etc. are used.
For example, as the latter method, as described in Patent Document 1 described above, a rotating rod is attached to the bottom surface of the paper feed tray, and a rotating lever that rotates with the rotation of the rotating rod is attached to one end of the rotating rod. The tip of the rotating lever is brought into contact with the bottom plate of the paper feed tray, and the tip of the rotating lever is rotated in accordance with the rotation of the rotating rod to move the tip of the bottom plate up and down. In this case, in order to rotate the rotating rod, the other end of the rotating rod is detachably connected to the rotation output shaft from the rotation driving means via the coupling member. In order to detachably connect the rotating rod, an engaging protrusion protruding from the outer periphery of the rotating rod is formed at the other end of the rotating rod, and the rotating output shaft into which the engaging protrusion can be inserted into the coupling member An insertion groove extending radially from the center axis of the coupling member to the inside from the end surface of the coupling member is provided, and the paper feed tray is pushed into the image forming apparatus and housed, whereby the engagement protrusion is inserted into the insertion groove of the coupling member. The rotation of the rotary drive means is transmitted to the rotary rod.
JP 2005-178925 A

As described above, in order to support accessibility, the sheet feeding device needs to include a lock unit that prevents the movement of the sheet feed tray and a unit that pushes up the bottom plate. Since the means and the pushing-up means for the bottom plate are respectively constituted by separate means, there is a problem that not only the structure is complicated, but the number of components is increased and the cost is increased.
The present invention has been made in consideration of the above circumstances, and has a simple structure and a small number of components, and includes a paper feed tray lock mechanism and a bottom plate push-up mechanism, and an image forming apparatus including the same. The purpose is to provide.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a paper feed tray that is detachably attached to the apparatus main body, and a paper feed when the paper feed tray is set at a predetermined position of the paper feed device In the paper feeding device having a paper push-up means for pushing up the bottom plate of the tray and bringing the uppermost paper of the paper stack placed on the bottom plate into contact with the feeding means, the paper push-up means pushes up the bottom plate A push-up member, and a rotating rod attached to the bottom surface of the paper feed tray, connected to the push-up member at one end, and an engaging means for connecting to a rotation driving means attached to the apparatus main body at the other end The rotating rod engaging means has an engaging protrusion protruding from the outer periphery of the rotating rod, and the rotational driving means is a coupling that engages with the engaging protrusion on the rotational output shaft of the rotational driving means. A coupling member, and the coupling member extends radially from the center axis of the rotation output shaft into which the engagement protrusion can be inserted and extends in parallel with the center axis of the rotation shaft from the end surface to the inside of the coupling member. An insertion groove, and an insertion groove that is connected to the inner end of the insertion groove and extends in the circumferential direction of the coupling. When the engagement protrusion is inserted into the insertion groove and the coupling member is rotated in a predetermined rotation direction by the rotation driving means, the engagement groove of the coupling member and the engagement protrusion are engaged. The sheet feed tray is prevented from being detached from the apparatus main body.

The invention according to claim 2 is the paper feeding device according to claim 1, wherein the push-up member is a rotating lever having one end connected to the rotating rod and the other end having a push-up portion that pushes up the bottom plate. It is characterized by.
The invention according to claim 3 is the paper feeding device according to claim 1 or 2, wherein a plurality of the engaging protrusions are arranged at predetermined intervals in the circumferential direction of the rotating rod, and the coupling member is inserted. A plurality of grooves and engaging grooves are formed corresponding to the positions of the engaging protrusions.
According to a fourth aspect of the present invention, in the paper feeding device according to any one of the first to third aspects,
The insertion groove and the engagement groove of the coupling member are formed more than the number of the engagement protrusions.
According to a fifth aspect of the present invention, there is provided an image forming apparatus including a paper feeding device and an image forming unit that forms an image on a sheet fed from the paper feeding device. It is a paper feeding device given in any 1 paragraph of 1 thru / or 4.

  According to the present invention, the coupling member includes an insertion groove extending radially from a center axis of the rotation output shaft into which the engagement protrusion can be inserted and extending from the end surface of the coupling member to the inside, and the insertion groove The engaging groove is connected to an inner end and extends in the circumferential direction of the coupling. The engaging groove can be inserted into the inserting groove of the coupling member. When the coupling member is inserted and rotated in a predetermined rotational direction by the rotation driving means, the engagement groove of the coupling member and the engagement protrusion are engaged, and the paper feed tray is detached from the apparatus main body. By preventing detachment, it is possible to provide a sheet feeding device including a sheet feeding tray locking mechanism and a bottom plate push-up mechanism and an image forming apparatus having the same with a simple structure and a small number of components. Become

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of a digital multi-function peripheral as an image forming apparatus according to an embodiment of the present invention. The digital multifunction machine 1 basically includes an image forming unit A, a paper feeding unit B, and a fixing unit C.
The image forming unit A includes a drum-shaped photoconductor 2 and an image forming element provided along the outer periphery thereof. The image forming element is rotated counterclockwise in the drawing (the rotation of the photoconductor 2) on the outer periphery of the photoconductor 2. The charging unit 3, the developing unit 4, the transfer unit 5, the cleaning blade 6, and the charge eliminating lamp 27 are provided in the same direction. Optical writing with a laser beam L is performed between the charging unit 3 and the developing unit 4 on the exposed surface of the photoreceptor 2. The laser beam L is emitted to the surface of the photoreceptor 2 from the optical scanning device 7 having a scanning optical system such as a polygon mirror and an imaging lens (not shown), and is substantially axially directed to the surface of the photoreceptor 2. Scanning is performed in the (main scanning direction).

  The charging unit 3 charges the surface of the photoconductor 2 to a predetermined potential. Optical writing is performed by the laser beam L, and an electrostatic latent image is formed on the surface of the photoconductor 2. The electrostatic latent image is developed with toner by the developing unit 4, transferred to a sheet P conveyed from a sheet feeding unit B described later by a transfer unit 5 using a transfer belt 5a, and sent to the fixing unit C side. The toner remaining on the surface of the photosensitive member 2 is scraped off by the cleaning blade 6, and the surface of the photosensitive member 2 is discharged by the discharging lamp 27, and then rotates again toward the charging unit 3. That is, charging, optical writing, development, transfer, cleaning, and static elimination processes are performed during one rotation of the photosensitive member 2, and this operation is repeated for each image (each image formation on a sheet).

The paper feed unit B includes four stages of paper feed trays 8, 9, 10, and 11 and a paper feed unit 12 provided at the upper part on the exit side of the paper feed trays 8 to 11 in the paper transport direction (arrow D direction). 13, 14, 15, a vertical conveyance path 20 including conveyance roller pairs 16, 17, 18, 19 for guiding sheets drawn from the respective paper feeding units 12 to 15 to the image forming unit A side, and a vertical conveyance path 20 is mainly composed of a registration roller pair 21 provided on the most downstream side in the sheet conveying direction. The side plates 20a and 20b forming the vertical conveyance path 20 are configured to be openable around the lower hinge as shown in the figure, and a jam has occurred on the vertical conveyance path 20 or the exit side of the paper feed units 12-15. In this case, the side plates 20a and 20b can be opened to perform jam processing. A registration sensor 21a is provided on the upstream side of the registration roller 21 in the sheet conveying direction so that the presence / absence of a sheet at the registration roller 21 position can be detected.
The fixing unit C includes a fixing unit 23 that includes a heating roller 23 a and a pressure roller 23 b provided immediately downstream of the transfer unit 5 in the sheet conveyance direction. A paper discharge path 25a for discharging the paper P to the paper discharge tray 26 via the paper roller 25 and a double-sided conveyance path 24a for carrying out the paper P to a double-side unit (not shown) are provided.

  Next, a paper feeding device that feeds the paper P one by one from the paper feeding trays 8, 9, 10 and 11 to the registration roller pair 21 will be described with reference to the drawings. FIG. 2 is a diagram showing a schematic configuration of the paper feed tray 8 used in the paper feed device according to the embodiment of the present invention. The paper feed tray 8 according to the present embodiment includes a bottom plate 81 that is supported by a bearing portion 82 on a support shaft 8a formed on a side wall of a box-like body that is open upward, and is rotatably attached. . Around the bottom plate 81, an end fence 88 that regulates the position of the end of the paper P and a side fence 89 that regulates the position of the side edge of the paper P are respectively in front of and behind the paper feed tray 8 (the feeding direction of the paper P described later). F) and a side (in a paper feed tray insertion direction E, which will be described later) are movably attached, moved in accordance with the size of the paper P stored in the paper feed tray 8, and moved. The positions of the rear end and the side end are regulated. A rotating rod 85, which is one constituent member of a sheet push-up means (not shown) for pushing up the bundle of sheets P, is attached to the end of the bottom plate 81 opposite to the bearing portion 82. The paper push-up means 50 is connected to a rotation drive means 51, a rotation rod 85, and a rotation output shaft 58 of the rotation drive means 51, which will be described later, and a coupling member 56 detachably connected to the rotation rod 85. , And a push-up member (described later) that is connected to the rotary rod 85 and moves the bottom plate 81 up and down as the rotary rod 85 rotates.

FIG. 3 is a cross-sectional view of the paper feed tray cut along line AA in FIG. FIG. 4 is a view showing a state where the bottom plate of the paper feed tray shown in FIG. 3 is raised. FIG. 5 is a cross-sectional view showing a state in which the paper feed tray shown in FIG. FIG. 6 is a cross-sectional view of a paper feeding device in which the paper feeding tray shown in FIG.
The rotating rod 85 is disposed in parallel to the insertion direction (arrow E direction) of the paper feed tray 8 with respect to the apparatus main body 1 and is rotatably supported by a support member 83 on the bottom wall 8 b of the paper feed tray 8. ing. A rotating lever 86, which is an example of the push-up member, is connected to one end 85a of the rotating rod 85. As shown in FIGS. 3 and 4, the rotating lever 86 rotates in the vertical direction (arrow G direction) with the rotation of the rotary rod 85, and as shown in FIG. Comes into contact with the bottom surface 81b of the bottom plate 81 to push up and rotate the front portion 81c of the bottom plate 81. As a result, as shown in FIG. 5, the front end Pa of the bundle of sheets P stacked on the bottom plate 81 is also pushed up.
When the uppermost sheet P of the bundle of sheets stacked on the bottom plate 81 pushed up in this way comes into contact with the paper supply roller 12a of the paper supply unit 12, this contact is detected as shown in FIG. Detected by the filler 89a of the sensor 89, the rotational drive of the rotational drive means 51 described later is stopped. As the rotation of the rotation driving means 51 is stopped, the rotation of the rotating rod 85 is also stopped, the pushing-up action of the rotating lever 86 against the bottom plate 81 is stopped, and the sheet feeding roller 12a and the uppermost sheet P are properly brought into contact with each other. It will be. As a result, the uppermost sheet P of the sheet bundle on the bottom plate 81 is fed out one by one by the rotation of the sheet feeding roller 12a, and the sheet P can be fed into the above-described conveyance path 20.

  A columnar engagement protrusion 87 that engages with a coupling member 56 to be described later is provided at an end portion 85 b opposite to the end portion connected to the rotation lever 86 of the rotation rod 85. Two protrusions are formed so as to protrude from the outer periphery in a direction orthogonal to the rotation shaft 85c (see FIG. 2). When the paper feed tray 8 is inserted into the apparatus main body 1 from the E direction (see FIG. 2) along the guide rail 30 formed on the apparatus main body 1, the engaging protrusion 87 of the rotating rod 85 is As shown in FIG. 6, a coupling member 56 connected to a rotation output shaft 58 of a rotation driving means 51 attached to the apparatus main body is detachably connected.

FIG. 7 is a perspective view showing a state in which the coupling member and the engaging protrusion of the rotating rod according to the embodiment of the present invention are detached. FIG. 8 is a perspective view showing a coupling member according to another embodiment of the present invention. FIG. 9 is a perspective view showing a state in which the coupling member and the engaging protrusion of the rotating rod according to another embodiment of the present invention are detached.
As shown in FIG. 7, the rotation drive means 51 includes a drive motor 52, a worm gear 53 attached to the output shaft of the drive motor 52, a worm wheel 54 that meshes with the worm gear 53, and a spur gear that meshes with the worm wheel 54. 55, a coupling member 56 attached to the rotation output shaft 58 of the spur gear 55 is provided. The coupling member 56 has a cylindrical shape, and a concave hole 56a into which the end portion 85b of the rotating rod 85 can be inserted is formed at the center. And it connects with the concave hole 56a of the coupling member 56, and it is parallel to the rotation output shaft 58 to the surrounding wall 56b radially from the central axis of the rotation output shaft 58 and from the free end 56c to the bottom 56e of the inner concave hole 56b. An insertion groove 56d having a width larger than the diameter of the engagement protrusions 87a and 87b extending into the groove and having four notches into which the engagement protrusions 87a and 87b can be inserted.

Further, an engagement groove 56f that is connected to the insertion groove 56d and has a cut larger in diameter than the diameters of the engagement protrusions 87a and 87b is formed on the peripheral wall 56b of the end portion 56d1 of the insertion groove 56d. Is formed. Accordingly, the engaging protrusions 87a and 87b of the rotating rod 85 are inserted into the insertion groove 56d of the coupling member 56, and the coupling member 56 is rotated in the direction in which the rotation driving means 50 is operated to raise the rotating lever 86. Then, the engagement protrusions 87a and 87b move from the insertion groove 56d of the coupling member 56 to the engagement groove 56f and engage with each other. As a result, with the rotation of the coupling member 56, the rotational force is transmitted and the rotating rod 56 rotates to raise the rotating lever 86. When the rotation of the coupling member 56 is stopped in this state, the engaging protrusions 87a and 87b of the rotating rod 84 engage with the engaging groove 56d of the coupling member 56, so that the paper feed tray 8 is opposite to the insertion direction E. The movement in the direction is prevented, and it is possible to prevent the paper feed tray 8 from being accidentally detached from the apparatus main body 1.
In this embodiment, four insertion grooves 56d are formed in the two engagement protrusions 87a and 87b so as to increase the opportunities for insertion of the tip 85b of the rotating rod 85 into the coupling member 56. ing. However, as shown in FIG. 8, two insertion grooves 56d and engagement grooves 56f of the same number as the engagement protrusions 87a and 87b can be formed in the coupling member 56. In this case, the interval between the engagement grooves 56f can be increased, and the strength of the coupling member 56 can be improved.

Further, as shown in FIG. 9, the number of the engagement protrusions is four, the insertion grooves 56d and the engagement grooves 56f of the coupling member 56 are the same number, and are inserted at positions corresponding to the positions of the engagement number protrusions. When the groove 56d is formed, the engagement with the engagement protrusions 87a, 87b, 87c, and 87d and the engagement grooves 56f1, 56f2, 56f3, and 56f4 (56f3 and 56f4 are not shown) is more reliable. It is possible to prevent the sheet feeding tray 8 from being accidentally detached from the apparatus main body 1.
In order to disengage the engagement protrusions 87a, 87b, 87c, 87d from the engagement grooves 56f1, 56f2, 56f3, 56f4, the rotation drive means is rotated in the reverse direction in the direction in which the rotation lever 86 is lowered. If stopped, the engaging protrusions 87a, 87b, 87c, 87d abut against the guide wall 56d2 of the insertion grooves 56d11, 56d12, 56d13, 56d14, and can move in the direction opposite to the E direction. The drawer 8 can be pulled out.
Moreover, in the said embodiment, the rotation lever 86 was used as a raising member of the baseplate 81, the front part of the baseplate 81 was pushed up, and it was made to push up in the state inclined. However, the structure is not limited to this structure, and the bottom plate 81 is moved up and down in parallel with the bottom portion 81a of the paper feed tray 8 by using a worm gear or the like that transmits the rotational force of the guide member and the rotary rod 85 in the vertical direction as a push-up member. You can also do it.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. It is a top view of the paper feed tray used with the paper feeder of one embodiment by the present invention. It is sectional drawing cut | disconnected by the AA line shape of FIG. It is sectional drawing which shows the state which raised the bottom plate of the paper feed tray shown in FIG. FIG. 4 is a cross-sectional view illustrating a state where the paper feed tray illustrated in FIG. 3 is mounted on the apparatus main body. FIG. 3 is a cross-sectional view of a paper feeding device in which the paper feeding tray shown in FIG. It is a perspective view which shows the state which removed the coupling member of one Embodiment by this invention, and the engagement protrusion of a rotating rod. It is a perspective view which shows the coupling member of other embodiment by this invention. It is a perspective view which shows the state which released | separated the coupling member and engaging protrusion of the rotating rod of other embodiment by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Apparatus main body, 2 Photoconductor, 3 Charging unit, 4 Developing unit, 5 Transfer unit, 6 Cleaning blade, 7 Optical scanning device, 8 Paper feed tray, 8a Support shaft, 8b Bottom wall, 9, 10, 11 Paper feed tray 12, 13, 14, 15 Paper feed unit, 16, 17, 18, 19 Transport roller pair, 20 Transport path, 21 Registration roller pair, 23 Fixing unit, 50 Push-up means, 51 Rotation drive means, 56 Coupling member, 56a concave hole, 56b peripheral wall, 56c free end, 56d insertion groove, 56e bottom part, 56f engagement groove, 58 rotation output shaft, 81 bottom plate, 82 bearing part, 83 support member, 84 detection sensor, 85 rotation rod, 85a one end, 85b other end, 85c rotating shaft, 86 rotating lever, 87a, 87b, 87c, 87d engaging protrusion

Claims (5)

A paper feed tray that is detachably attached to the apparatus main body, and a sheet bundle placed on the bottom plate by pushing up the bottom plate of the paper feed tray when the paper feed tray is set at a predetermined position of the paper feed device. In a paper feeding device having a paper pushing-up means for bringing the uppermost paper into contact with the feeding means,
The paper push-up means is a push-up member that pushes up the bottom plate;
A rotating rod attached to the bottom surface of the paper feed tray, connected to the push-up member at one end, and an engaging means for connecting to a rotation driving means attached to the apparatus main body at the other end;
The rotating rod engaging means has an engaging protrusion protruding from the outer periphery of the rotating rod,
The rotation drive means has a coupling member that engages with the engagement protrusion on the rotation output shaft of the rotation drive means,
The coupling member includes an insertion groove extending radially from the center axis of the rotation output shaft into which the engagement protrusion can be inserted and extending in parallel with the center axis of the rotation shaft from the end surface to the inside of the coupling member. An insertion groove that is connected to the inner end of the insertion groove and that can be inserted into the engagement protrusion extending in the circumferential direction of the coupling, and the insertion groove;
When the engagement protrusion is inserted into the insertion groove of the coupling member and the coupling member is rotated in a predetermined rotation direction by the rotation driving means, the engagement groove and the engagement of the coupling member are A paper feeding device characterized in that a projection is engaged to prevent the paper feeding tray from being detached from the main body. The paper feeding device according to claim 1.
The paper feeding device, wherein the push-up member is a rotating lever having one end connected to the rotating rod and having a push-up portion that pushes up the bottom plate at the other end. The sheet feeding device according to claim 1 or 2,
A plurality of the engaging protrusions are arranged at predetermined intervals in the circumferential direction of the rotating rod,
A plurality of insertion grooves and engagement grooves of the coupling member are formed corresponding to the arrangement positions of the engagement protrusions. The paper feeding device according to any one of claims 1 to 3,
The paper feeding device, wherein the insertion groove and the engagement groove of the coupling member are formed more than the number of the engagement protrusions. In an image forming apparatus comprising a sheet feeding device and an image forming unit that forms an image on a sheet fed from the sheet feeding device,
The image forming apparatus according to claim 1, wherein the sheet feeding device is the sheet feeding device according to claim 1.

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