JP2006240801A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper sheet tray capable of preventing interference of a rack member (inner tray member) of a side fence and an extension tray with a simple composition. <P>SOLUTION: The rack members 7a, 7b respectively connected to a pair of side fences 4 (only one of them, a side fence 4a, is shown in the figure) are in the paper sheet tray. Racks (not shown in the figure) provided for the respective rack members are engaged with a pinion gear 9. The rack members 7a, 7b are provided with arms 10, 10 as engagement parts. When the side fences 4 move, the arms 10, 10 are in slide contact with ribs 11, 11 and the friction force of the arms and the ribs prevents the rack members 7a, 7b from falling, which prevents the interference with the extension tray 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paper tray in an image forming apparatus such as a copying machine, a printer, and a facsimile, and more particularly to a paper tray having an extension tray.

JP 2003-312904 A JP 11-59922 A JP-A-7-223758

  In recent years, in image forming apparatuses such as copying machines, printers, and facsimiles, a so-called front loading type apparatus in which a sheet feeding cassette or tray is pulled out to the front side of the apparatus main body to supply paper is becoming mainstream. ing. Also, a printer equipped with a manual paper feeder on the side surface of the apparatus main body is widely used for printing or copying on special paper or interrupt copying.

  In the manual paper feeder, in order to cope with various paper sizes, the paper tray (manual tray) is provided with a tray extending means for stacking a large size paper in addition to a normal paper stacking portion. There are many. Examples of conventional tray extending means are shown in FIGS.

  The tray extension means 52 shown in FIG. 9 is rotatably mounted on the end portion of the tray 51 by a shaft 53 so that it can be pulled out from the tray 51 and stored in the tray 51.

  Further, the tray extension means 54 shown in FIG. 10 is slidably supported on the tray 51, and is configured to be able to be pulled out from the tray 51 and stored in the tray 51.

  Generally, these tray extension means are pulled out from the tray when large-size sheets are fed, and the rest are stored in the tray. However, such a tray extension means has a drawback that it lacks rigidity for stacking a large amount of (a large number of) sheets. In addition, when the sheets are stacked, the end of the sheet (the end in the width direction) falls, which may adversely affect the image, particularly transfer failure in a color machine.

  Therefore, a configuration has been proposed in which a large extension tray 55 as shown in FIG. 11 is slidably supported on the tray 51 and can be pulled out from the tray 51 and stored in the tray 51. For example, Patent Document 1 describes a manual feed tray including an extension tray.

  By the way, the paper feed tray is usually provided with side fences for guiding both ends in the paper width direction. Generally, in order to cope with various paper sizes (paper widths), the side fence is provided so as to be movable in the paper width direction (direction orthogonal to the paper feeding direction). As a configuration in which the side fence can be moved in the paper width direction, in the case of transporting paper based on the center reference, rack members (members in the tray) are provided integrally or attached to the side fences on both sides, and each side fence is provided. A configuration (rack and pinion system) is widely used in which a pair of side fences are moved at an equal distance from the center reference by meshing the rack with a pinion gear. For example, Patent Documents 2 and 3 describe a manual feed tray having a side fence by a rack and pinion method.

  FIG. 12 shows an example of a manual feed tray having an extension tray and a rack and pinion type side fence. This figure is a cross-sectional view of the manual feed tray cut along a plane orthogonal to the paper feeding direction. In this figure, the direction perpendicular to the drawing is the paper feeding direction.

  As shown in the figure, a pair of side fences 56a and 56b are provided on the upper surface of the tray 51 for guiding both sides in the sheet width direction. The side fences 56a and 56b are provided so as to be movable in the left-right direction in the figure. A rack member 57a is provided on the left side fence 56a, and a rack member 57b is provided on the right side fence 56b. The racks provided on the rack members 57a and 57b are meshed with a pinion gear 58 disposed therebetween. An extension tray 55 is provided in the tray inner space below the racks 57 a and b and the pinion gear 58 so as to be movable in a direction perpendicular to the drawing.

  When the side fences 56a and 56b are opened as shown in FIG. 12, there is no problem because the rack members 57a and 57b are pressed against the pinion gear 58 attached to the tray 51, but as shown in FIG. In addition, when the side fences 56a and 56b are moved to the center (when small-size paper is fed), the tips of the rack members 57a and 57b are lowered downward, and the extension tray 55 (not shown in FIG. 13) is used. There is a problem that the extension tray 55 cannot be moved due to interference. As shown in FIG. 14, this occurs because the rack member 57 bends or falls downward by its own weight with the attachment portion 59 to the side fence 56 as a fulcrum.

  In order to prevent this, as shown in FIG. 15, it is conceivable to provide a cover 60 that prevents interference between the rack member 57 and the extension tray 55. However, the cost increases due to an increase in the number of parts, and the thickness of the tray increases. As a result, there is a problem that the size of the entire image forming apparatus is increased.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a paper tray and an image forming apparatus that can solve the above-described problems in the conventional paper tray and can prevent interference between the rack member of the side fence and the extension tray with a simple configuration. .

  According to the present invention, there is provided a paper tray including a movable side fence that guides the paper width direction and an extension tray that can be housed and pulled out. A tray inner member that moves in the tray; and an engagement portion provided on the tray inner member is engaged with a sliding contact portion provided on a case of the paper tray, and the engagement portion is moved when the side fence is moved. This is solved by being brought into sliding contact with the sliding contact portion.

Further, it is preferable that the engaging portion is engaged with the sliding contact portion by member elasticity.
Moreover, it is preferable that the engaging portions are provided at both ends in the longitudinal direction of the tray inner member.

  In addition, the side fence includes a pair of side fences that guide both sides in the paper width direction, the tray inner member of each side fence has a rack portion, and the rack portion is a gear supported in the paper tray. It is preferable that the pair of side fences are provided so as to be movable in a direction orthogonal to the paper feeding direction while maintaining an equal distance from the paper conveyance reference.

  Further, according to the present invention, the above problem is solved by an image forming apparatus comprising the paper tray according to any one of claims 1 to 4 as a manual feed tray.

  According to the paper tray of the present invention, the engaging portion provided on the tray inner member is engaged with the sliding contact portion provided on the case of the paper tray, and the engaging portion is slidably contacted with the sliding contact portion when the side fence is moved. Therefore, the drop of the tray inner member is prevented, and the interference between the tray inner member and the extension tray is prevented. Therefore, the operation of the extension tray is not hindered.

  In addition, since the configuration is simple, the number of parts does not increase and the cost increase can be suppressed. Furthermore, the thickness of the tray does not increase and the size of the image forming apparatus is not increased.

  According to the configuration of the second aspect, since the engaging portion is engaged with the sliding contact portion by the member elasticity, it is not necessary to provide a complicated pressing mechanism or the like, and it is possible to prevent the tray configuration from becoming complicated and to suppress an increase in cost.

According to the configuration of the third aspect, since the engaging portions are provided at both ends in the longitudinal direction of the tray inner member, it is possible to more reliably prevent the tray inner member from dropping.
According to the configuration of claim 4, a pair of side fences that guide both sides in the paper width direction are provided as side fences, the tray inner member of each side fence has a rack portion, and the rack portion is supported in the paper tray. Since the pair of side fences are meshed with each other and are provided so as to be movable in the direction orthogonal to the paper feeding direction while maintaining the same distance from the paper conveyance reference, the tray inner member in the rack and pinion type paper tray, that is, the rack member Can be prevented and interference with the extension tray can be prevented.

  According to the image forming apparatus of the fifth aspect, since the paper tray in which the members in the tray are prevented from dropping is provided as the manual feed tray, the operation of the extension tray in the manual feed tray is not hindered. For this reason, even when a large-size sheet is fed from the manual feed tray, it is possible to prevent the sheet from sagging at the trailing edge of the sheet, and the image quality is not adversely affected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 and 2 are external perspective views showing an example of a paper tray according to the present invention. This paper tray 1 is used as a manual feed tray of an image forming apparatus (FIG. 8) described later, and is hereinafter referred to as a manual feed tray 1.

  As shown in the figure, the manual feed tray 1 includes a tray cover 2 that constitutes a part of the exterior cover of the image forming apparatus, a manual feed base 3 that is a paper stacking portion, and a pair of left and right side fences 4a that guide both sides in the paper width direction. 4b, extension tray 5 and the like. The tray cover 2 and the manual feed base 3 constitute a tray case, and the extension tray 5 can be stored and pulled out of the tray case as shown in FIGS. As shown in FIG. 4, the extension tray 5 is pulled out and the sheets are stacked.

5 and 6 are a perspective view and a bottom view of the side fences 4a and 4b and a rack member (a member in the tray) provided on the side fence.
As shown in these drawings, rack members 7a and 7b are provided integrally or attached to the side fences 4a and 4b, respectively. Racks 8 and 8 are provided on opposite sides of the rack members 7a and 7b, and the racks 8 and 8 of both side fences are meshed with a pinion gear 9 that is rotatably supported on the lower surface of the manual feed table 3 ( (See also FIG. 3). By this rack and pinion, the pair of side fences 4a and 4b move from the center of the gear 9 (from the sheet conveyance reference) while maintaining an equal distance from each other. A portion (not shown) for connecting the side fence 4 and the rack member 7 is fitted in the slit 6 of the manual feed table 3 shown in FIG. 1, and the side fences 4 a and 4 b are connected to the manual feed table 3. The top moves in a direction perpendicular to the paper feeding direction.

  Arms (engaging portions) 10 and 10 are provided at the front end portions of the rack members 7a and 7b so as to protrude obliquely. As shown in FIGS. 3 and 4, ribs (sliding contact portions) 11 and 11 are provided so as to protrude from the lower surface of the manual feed table 3, that is, the inner surface of the tray 1. When the side fences 4 a and 4 b and the rack members 7 a and 7 b are set on the tray 1, the arm 10 is arranged so that the arm 10 at the front end of the rack member comes into contact with the side surface of the rib 11 as shown in FIGS. Set by bending.

  Since the rack members 7a and 7b are resin members in this example, the arm 10 has appropriate elasticity, and in the initial state, the arm 10 projects obliquely as shown in FIG. By bending the arm 10 and engaging the side surface of the rib 11 as shown in FIG. 7, the tip of the arm 10 is urged toward the rib 11 as shown by the arrow D in FIG. 11 is engaged. Thereby, when the rack members 7a and 7b move along with the movement of the side fences 4a and 4b, the arm 10 moves while sliding on the rib 11, and a frictional force is generated between them. This frictional force prevents the front ends of the rack members 7a and 7b from dropping downward in FIGS. Therefore, a space for moving the extension tray 5 disposed in the tray 1 located below the rack members 7a and 7b is secured, and the rack members 7a and 7b and the extension tray 5 do not interfere with each other. The extension tray 5 can be prevented from being pulled out and stored.

In this example, since the arms 10 are formed at both end portions in the longitudinal direction of the rack members 7a and 7b, the rack members 7a and 7b are more reliably prevented from falling.
The side fence 4 and the rack member 7 may be an integral part, or may be configured to connect both as separate parts.

  Moreover, the structure which attaches the part of the arm 10 to the rack member 7 separately from the rack member 7 may be sufficient. Moreover, the structure which presses an arm part to the rib 11 by biasing means, such as a spring, is also possible.

  In the manual feed tray of this example, the interference between the rack members 7a and 7b and the extension tray 5 can be prevented with a simple configuration, the number of parts does not increase, and the cost increase can be suppressed. Further, the thickness of the manual feed tray is not increased, and the size of the image forming apparatus is not increased. Further, the extension tray 5 can have a size (width) substantially equal to the width of the manual feed tray 1, and even when a large size paper is fed from the manual feed tray, it is possible to prevent sagging of both ends of the paper, thereby reducing the image quality. I will not let you.

Next, an example of an image forming apparatus including the manual feed tray 1 will be described with reference to FIG.
The image forming apparatus shown in FIG. 8 is a so-called tandem type full-color apparatus, which is configured as a copying apparatus with an image reading unit. The copying apparatus of this example has an apparatus main body 100 mounted on a paper feed table 200, a scanner 300 is disposed at the top of the apparatus main body 100, and an automatic document feeder (ADF) 400 is further provided thereon. is there.

  An intermediate transfer unit 20 having an endless belt-like intermediate transfer member 21 as the center is disposed at the approximate center of the apparatus main body 100. Four image forming units 30 are arranged side by side along the upper side of the intermediate transfer belt 21. In each image forming unit 30, devices necessary for the electrophotographic process are arranged around the photosensitive drum 31.

  The intermediate transfer belt 21 is stretched around a plurality of support rollers so as to be able to rotate and convey clockwise in the drawing. Inside the intermediate transfer belt 21, a transfer roller as a primary transfer unit is disposed at a position facing the photosensitive drum 31 of each image forming unit.

  An exposure device 40 is disposed above each image forming unit 30. Write light from the exposure device 40 is applied to the photosensitive drum 31 of each image forming unit 30.

  A transfer belt 22 is disposed below the intermediate transfer unit 20. One roller that supports the transfer belt 22 is configured as a secondary transfer roller, and secondarily transfers an image on the intermediate transfer belt 21 to a recording material (transfer paper or the like).

  A fixing device 23 is provided on the left side of the transfer belt 22. The transfer belt 22 also has a function of conveying the sheet after image transfer to the fixing device 23. A paper discharge tray 24 is provided on the left side of the fixing device 23. A manual feed tray 1 is provided on the side of the apparatus opposite to the paper discharge tray 24. The manual feed tray 1 is configured to be openable and closable with respect to the apparatus main body 100.

  A sheet reversing unit 25 is provided at the lowermost part of the apparatus main body 100. The paper feed table 200 is provided with two stages of paper feed cassettes 27 and 27.

  Now, when making a copy using the color copying apparatus of this example, the original is set on the original tray or contact glass of the ADF 400. Then, when a start switch provided on an operation panel (not shown) is pressed, the scanner is driven, and reflected light from the light source is reflected by a mirror to enter a reading sensor through an imaging lens (not shown) to read document information.

  Similarly, when a start switch provided on the operation panel is pressed, the intermediate transfer belt 21 is rotated and conveyed by a drive motor (not shown). At the same time, the photoconductors 31 are rotated in the individual image forming units 30 to form black, yellow, magenta, and cyan monochrome images on the photoconductors 31, respectively. These single color images are sequentially transferred onto the intermediate transfer belt 21 to form a composite color image.

When the start switch is pressed, the paper is fed out from the paper feed table 200 or the manual feed tray 1 and is brought into contact with the registration roller 33 to be temporarily stopped.
Then, the registration roller 26 is rotated in synchronization with the composite color image on the intermediate transfer belt 21, the sheet is fed between the intermediate transfer belt 21 and the transfer belt 22, and the image is transferred by the secondary transfer unit to transfer the sheet. Record a color image on top. The sheet after the image transfer is sent to the fixing device 23 where the toner image is fixed and discharged to the discharge tray 24.

  Since the manual feed tray 1 includes the extension tray 5 as described above, it is possible to manually feed even a large size paper. At this time, by providing the large extension tray 5, even when a large size paper is manually fed, the image quality is not deteriorated due to the falling edge of the paper. Further, since the rack members 7a and 7b of the side tray of the manual feed tray are configured so as not to interfere with the extension tray 5, the extension tray 5 can be prevented from being pulled out and stored. Since the thickness of the manual feed tray does not increase, the size of the entire image forming apparatus does not increase.

Although the present invention has been described above with reference to the illustrated examples, the present invention is not limited thereto.
The configuration for preventing the rack member from hanging down in the paper tray is applicable not only to the manual feed tray but also to a tray having a side fence and a paper feed table. For example, the present invention can also be applied to a document feeder in a facsimile or the like.

  The paper tray according to the present invention is not limited to an electrophotographic image forming apparatus, and can be used as a manual feed tray of an image forming apparatus using an arbitrary image forming system such as an ink jet system.

It is an external perspective view showing an example of a paper tray according to the present invention. FIG. 6 is an external perspective view of the paper tray from another direction. It is sectional drawing of the paper tray. It is sectional drawing for demonstrating drawer | drawing-out of an extension tray. It is a perspective view of a side fence and a rack member (tray inner member). It is a bottom view of a side fence and a rack member (member in a tray). It is a partial top view which shows a mode that the arm of the rack member and the rib of the tray were engaged. FIG. 2 is a cross-sectional view illustrating an example of an image forming apparatus including the paper tray of FIG. 1 as a manual feed tray. It is a perspective view which shows an example of the conventional tray extension means. It is a perspective view which shows another example of the conventional tray extension means. It is a perspective view which shows an example of the conventional paper tray which has an extension tray. It is sectional drawing which shows an example of the manual feed tray which has an extension tray and a side fence. It is sectional drawing which shows the depression of the rack member in the tray. It is a partial side view which shows the attachment part to the side fence of a rack member. It is sectional drawing which shows an example of the conventional tray which prevented the rack member from falling.

Explanation of symbols

1 Paper tray (bypass tray)
2 Tray cover 3 Manual feed table 4a, 4b Side fence 5 Extension tray 6 Slit 7a, 7b Rack member (in-tray member)
8 rack 9 pinion gear 10 arm (engagement part)
11 Rib (sliding contact part)
100 Copier body

Claims (5)

In a paper tray comprising a movable side fence that guides the paper width direction and an extension tray that can be stored and pulled out,
The tray has a tray inner member that is integrally or connected to the side fence and moves in the paper tray, and the engaging portion provided in the tray inner member is engaged with the sliding contact portion provided in the case of the paper tray. The paper tray is characterized in that the engagement portion is brought into sliding contact with the sliding contact portion when the side fence is moved. The paper tray according to claim 1, wherein the engaging portion is engaged with the sliding contact portion by member elasticity. The paper tray according to claim 1, wherein the engaging portion is provided at both ends in the longitudinal direction of the tray inner member. The side fence includes a pair of side fences that guide both sides in the paper width direction, the tray inner member of each side fence has a rack portion, and the rack portion is engaged with a gear supported in the paper tray. 2. The paper tray according to claim 1, wherein the pair of side fences are provided so as to be movable in a direction orthogonal to the paper feeding direction while maintaining an equal distance from the paper conveyance reference. An image forming apparatus comprising the paper tray according to claim 1 as a manual feed tray.

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