JP2007112558A - Paper feeding device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To drastically reduce contact resistance during operation to slantly take in/out a cassette while enabling regulation in right and left directions by providing flanges for rollers, and to improve the operability of the cassette as a result. <P>SOLUTION: The flanges 21a, 22a serving as regulating parts in the direction orthogonal to the direction to take in/out the cassette 2 are provided in the rail rollers 21, 22 supporting cassette rails 13, 14 mounted to the cassette 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a printer, a copying machine, and a facsimile, and a paper feeding apparatus that supplies a sheet such as recording paper to such an image forming apparatus.

  2. Description of the Related Art Conventionally, image forming apparatuses such as printers, copiers, and facsimiles generally include a paper feeding device that feeds a sheet such as recording paper to an image forming unit. A sheet storage means (hereinafter referred to as a cassette) for storing sheets is known to be detachably attached to the apparatus body.

  In such an image forming apparatus, the cassette serving as the sheet storage means is disposed at the sheet feeding position of the apparatus main body, and at the time of image formation, the sheets stored in the cassette are sequentially conveyed to the image forming unit, and the image forming unit The image is recorded on the sheet.

  In this sheet feeding device, sheets are appropriately stacked and stored, and are detachable from the main body of the image forming apparatus to be replenished as necessary, and are of a pull-out type. A series of operations such as closing is essential.

  In the drawer method, a rail is generally provided on the main body of the image forming apparatus, and a cassette can slide on the rail.

  When pulling out the sheet, the sheet is often replenished, and there is no sheet or the remaining sheet is small. For this reason, since the entire cassette is relatively light, the pulling operation is easy. On the other hand, when the sheet is replenished and closed, the sheet is full or close to it, and the weight of the entire cassette increases. If the closing operation is performed in this state, the frictional force due to the increase in weight increases and the operating force also increases, which is not preferable for the user. Applying grease to the image forming apparatus or cassette, providing a sliding member, or providing a rotatable roller for friction. It is known to reduce the force (see, for example, Patent Document 1).

  As shown in FIG. 14, the guide rails 15 and 16 are provided in the image forming apparatus 1 for loading and unloading the cassette 2, and the cassette rails 13 and 14 are provided on the side of the cassette 2 as shown in FIG. A structure in which the cassette is guided by guide rails 15 and 16 and can guide the cassette in the direction of arrow a is known.

  Further, a sliding member 29 having a low resistance for the purpose of reducing the frictional force on the front side of the guide rails 15 and 16 provided in the image forming apparatus 1 as shown in FIG. Some are known to have 30. This is because the guide rails 15 and 16 are generally formed of sheet metal on the image forming apparatus 1 and the cassette rails 13 and 14 on the side of the cassette 2 are formed of a resin material. 14 shavings and abnormal noise are prevented.

In addition, in order to reduce the frictional force during loading and unloading, it is also known that rollers 21 and 22 are rotatably fixed on the front side of the guide rails 15 and 16 as shown in FIGS. 16 and 17 to further reduce the resistance. Yes.
JP-A-6-92485

  However, the slide members 31 and 32 or the rollers 21 and 22 provided on the guide rails 15 and 16 of the image forming apparatus 1 described above are provided to reduce the frictional force and improve the operability as follows. There is a problem.

  When the cassette is taken in and out, there is no problem if it can be operated so that it can be drawn out in parallel with the direction of arrow a in FIG. 14, but it is difficult to accurately grasp and operate the center of gravity of the cassette 2. Furthermore, since the center of gravity of the entire cassette changes depending on the amount and size of the sheet, and the left and right frictional forces change in and out, the parallel operation is impossible and an inclination as shown by the arrow c always occurs. At this time, although some clearance is provided in the direction perpendicular to the direction of taking in and out of the arrow b direction, the clearance is not excessively increased, but conversely, a certain degree of inclination is restricted. .

  When the inclination occurs, the side surfaces 13a and 14a of the cassette rails 13 and 14 as shown in FIGS. 16 and 17 come into contact with the end portions 15a and 16a of the guide rails 15 and 16, respectively. This contact becomes a large resistance, which hinders the operation of inserting and removing the cassette and impairs the operability.

  When the resistance increases and the operation becomes heavy, the operation force is further increased to increase the resistance, causing problems such as part scraping due to abnormal rubbing, development of abnormal noise, and deterioration of operability.

  The present invention provides a cassette for stacking sheets to be fed to an image forming unit of an image forming apparatus main body, and the cassette is moved between a first position and a second position with respect to the image forming apparatus main body. A roller guide fixed to the image forming apparatus so as to support the cassette, and to restrict the direction perpendicular to the guide direction of the cassette. Further, the roller member is provided with a flange.

  As described above, according to the present invention, by providing a flange on the roller, the contact resistance due to the operation at the time of loading / unloading of the cassette, which also serves as a restriction in the left-right direction, can be greatly reduced. This has the effect of improving the performance.

  Embodiments of the present invention will be described below.

  In FIG. 6, reference numeral 1 denotes a laser beam printer as an image forming apparatus, which has the following functions.

  The cassette 2 is a cassette in which sheets S are stacked and stored, and cassette rails 13 and 14 are integrally formed on both sides. The cassette 2 is configured such that the cassette rails 13 and 14 are guided by a pair of guide rails 15 and 16 provided in the main body of the image forming apparatus, and can be pulled out toward the front side of the sheet of FIG.

  Reference numeral 3 denotes a pickup roller, which feeds out the sheets S stacked on the cassette 2 from the uppermost side. Reference numeral 4 denotes a separation roller pair including a feed roller and a retard roller, which separates the sheets S fed by the pickup roller 3 one by one. Transport.

  Reference numeral 7 denotes a process cartridge containing a known process unit relating to the image forming apparatus, which is detachably provided from the apparatus main body. A photosensitive drum 7a as an image carrier is built in the process cartridge, and a laser image is applied to the photosensitive drum 7a by a laser exposure device 8 according to image information to form a toner image. The Further, the transfer roller 9 is pressed against the photosensitive drum 7a, and the toner image on the surface of the photosensitive drum 7a is transferred to the sheet S when the sheet S passes between the photosensitive drum 7a and the transfer roller 9. A fixing device 10 fixes the toner image by applying heat and pressure to the sheet S on which the toner image is transferred. Then, the sheet S after image fixing is conveyed and discharged by a discharge roller pair 11 to a discharge tray 12 formed on the upper surface of the apparatus.

  Next, the structure of the cassette as the sheet storage means will be described below with reference to FIG. 1. At the bottom of the cassette 2, an intermediate plate 19 for stacking sheets is rotatably held around a rotation center 19a. When the cassette 2 is pulled out, it is dropped to the bottom of the cassette as shown in FIG. When the cassette 2 is stored in the image forming apparatus, the uppermost sheet S on the intermediate plate 19 is controlled to an optimum height that can be fed by the pickup roller 3 by a lift-up mechanism (not shown). In the cassette 2, a pair of width regulating plates 17 that regulate the side surfaces of the sheets S stacked in the cassette 2 are arranged to face each other, and a rear end regulating plate 18 that regulates the rear end in the conveyance direction of the sheet is provided. Has been placed. Marks 20 indicating the upper limit of sheets that can be stacked in the cassette 2 are engraved on the surfaces of the width restricting plate 17 and the rear end restricting plate 18 facing the sheet S.

  Next, guide means for guiding when the cassette of the present invention is taken in and out of the apparatus main body will be described.

  1 is an enlarged view when the cassette 2 is not provided, and a pair of rail rollers 21 and 22 are not shown on the front side of the pair of guide rails 15 and 16 provided in the image forming apparatus main body in FIGS. 4 and 5. The flanges 21a and 22a are provided at the respective end portions to restrict the horizontal direction (arrow b direction) of the cassette 2 with respect to the image forming apparatus. Since the cassette 2 is on the rail rollers 21 and 22, it is possible to reduce the contact resistance and improve the operation force when the cassette is put in and out. Since the flanges 21a and 22a provided at the end portions of the rail rollers 21 and 22 are in contact with the tilted operation in the direction of the arrow c, the cassette rails 13 and 14 as shown in the enlarged view 7 of FIG. The side surfaces 13a and 14a of the guide rails 15 and 16 are not in contact with the front end portions 15a and 16a of the guide rails 15 and 16 as shown in FIGS. The operability can be improved by reducing both frictional forces.

  During the loading / unloading operation, it is difficult to operate the image forming apparatus in parallel as shown in the direction of arrow a in FIG. 1, and it is always tilted in either direction as shown in the direction of arrow c. This is because it is difficult to accurately grasp and operate, and the center of gravity of the entire cassette changes depending on the amount and size of the sheet, and the left and right frictional forces at the time of loading and unloading also change. Therefore, the effect on the operability of the flanges 21a and 22a provided at the end portions of the rail rollers 21 and 22 is great.

  Also, as shown in FIGS. 8 and 9, by providing rotatable cassette rail rollers 23 and 24 on the back side of the cassette rails 13 and 14 provided in the cassette 2, the rail rollers 21 and 22 or the cassette rail rollers are always provided. Since it is supported by 23 and 24, operability can be further improved. The cassette rail rollers 23 and 24 are inclined by their own weight when the cassette 2 is pulled out, and the contact resistance with the guide rails 15 and 16 can be reduced.

(Other embodiments)
The example shown in FIG. 10 is an example in which the position of the flange described in FIG. 7 is provided from the outside to the inside, and the intended effect is the same.

  In the example shown in FIG. 11, the flange 21a is provided only on one side (right side in the figure) of the left and right rail rollers, and the restriction in the direction of the arrow b is performed by the recess 13b of the right cassette rail 13.

  In the example shown in FIG. 12, the flanges 21a and 22a of the rail roller are replaced by the side rollers 27 and 28 which are separate members. The rails 21 and 22 are provided on the guide rails 15 and 16 so as to be freely rotatable. The side surfaces 13a, 14a of the cassette rails 13, 14 are in contact with the side rollers 27, 28 with the inclination of time.

  In FIG. 13, cassette rail rollers 25 and 26 having flanges 25a and 26a on the back side of the cassette rails 13 and 14 of the cassette 2 are rotatably provided. With respect to the inclination when the cassette 2 is put in and out, It is the structure regulated by the edge parts 15b and 16b of a guide rail.

  Although the present invention is not shown in the figure, the above-described ones shown in FIGS. 13 and 4 and 5 are implemented at the same time, not only in the main body of the image forming apparatus, but also in an optional device cassette, etc. The present invention is not limited to the above embodiment, and various modifications can be made without departing from or changing the technical idea of the present invention.

1 is a perspective view of an image forming apparatus according to an embodiment of the present invention. It is a principal part expansion perspective view of the guide means in embodiment of this invention. It is a principal part expansion perspective view of the guide means in embodiment of this invention. It is a principal part expansion perspective view when the cassette in the embodiment of the present invention is pulled out. It is a principal part expansion perspective view when the cassette in the embodiment of the present invention is pulled out. FIG. 3 is a cross-sectional view of the image forming apparatus according to the embodiment of the present invention along the sheet conveyance direction. FIG. 3 is an enlarged cross-sectional view of a main part along the sheet conveying direction of the image forming apparatus according to the embodiment of the present invention. It is a principal part expansion perspective view in embodiment of this invention. It is a principal part expansion perspective view in embodiment of this invention. FIG. 6 is an enlarged cross-sectional view of a main part along a sheet conveying direction of an image forming apparatus according to another embodiment of the present invention. FIG. 6 is an enlarged cross-sectional view of a main part along a sheet conveying direction of an image forming apparatus according to another embodiment of the present invention. FIG. 6 is an enlarged cross-sectional view of a main part along a sheet conveying direction of an image forming apparatus according to another embodiment of the present invention. FIG. 6 is an enlarged cross-sectional view of a main part along a sheet conveying direction of an image forming apparatus according to another embodiment of the present invention. It is a perspective view which shows an example of the conventional image forming apparatus. FIG. 15 is a cross-sectional view along the sheet conveying direction of the image forming apparatus shown in FIG. It is a principal part expansion perspective view of the conventional guide means. It is a principal part expansion perspective view of the conventional guide means.

Explanation of symbols

1 Image forming device
2 cassette
3 Pickup roller
4 Separating roller pair
5 Conveyor roller pair
6 Transport roller pair
7 Process cartridge
8 Laser exposure equipment
9 Transfer roller
10 Fixing device
11 Discharge roller pair
12 Output tray
13 Cassette rail
14 Cassette rail
15 Guide rail
16 Guide rail
17 Width regulating plate
18 Rear end regulating plate
19 Middle plate
20 Upper limit mark
21 Rail roller
22 Rail roller
23 Cassette rail roller
24 Cassette rail roller
25 Cassette rail roller
26 Cassette rail roller
27 Side roller
28 Side roller
29 Sliding member
30 Sliding member

Claims (4)

A cassette in which sheets to be fed to the image forming unit of the image forming apparatus main body are stacked;
Cassette guide means for supporting the cassette so as to be movable in a first position and a second position with respect to the image forming apparatus main body;
With
A roller member that is rotatably fixed to support the cassette is provided in the main body of the image forming apparatus, and a flange is provided in the roller member to enable regulation in a direction orthogonal to the guide direction of the cassette. A paper feeder characterized by. A cassette in which sheets to be fed to the image forming unit of the image forming apparatus main body are stacked;
Cassette guiding means capable of moving the cassette between a first position and a second position with respect to the image forming apparatus main body;
With
A roller member that is rotatably fixed to support the cassette is provided on the cassette, and a flange is provided on the roller member to enable regulation in a direction orthogonal to the guide direction of the cassette. Paper feeding device to be used. A cassette in which sheets to be fed to the image forming unit of the image forming apparatus main body are stacked;
Cassette guiding means capable of moving the cassette between a first position and a second position with respect to the image forming apparatus main body;
With
A rotatable roller member that supports the cassette is provided in the main body of the image forming apparatus, and another rotatable roller member that can be regulated in a direction orthogonal to the guide direction of the cassette. A paper feeding device provided.   An image forming apparatus comprising the paper feeding device according to claim 1.

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