JP2008007242A - Paper feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeding device provided with an external air opening and closing mechanism capable of suppressing increase of load as much as possible when mounting and pulling out a paper feeding tray. <P>SOLUTION: This paper feeding device provided with the paper feeding tray for loading a transfer material on it, a storage case body capable of storing or pulling the paper feeding tray in/out of it by slide operation, and a sealing member for shutting off external air provided in a clearance between the paper feeding tray and the storage case body has an external air shutting-off mechanism in which the sealing member is abutted on the paper feeding tray or the storage case body by elastic deformation while the paper feeding tray is stored in the storage case body and the sealing member leaves the paper feeding tray or the storage case body during slide operation for storing or pulling out the paper feeding tray. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a paper feeding device provided in an image forming apparatus such as an electrophotographic copying machine, a printer, and a fax machine, and more particularly, to a paper feeding device having a paper feeding tray that can be taken in and out of the apparatus main body.

  In the image forming apparatus, when the transfer material, which is a sheet loaded on the sheet feeding device, absorbs moisture, the transfer material is easily curled, which causes problems such as a sheet feeding failure and a decrease in electrical resistance of the sheet, resulting in a transfer omission.

  Even if paper is supplied to the paper feed tray immediately after it is taken out of the package, if it is left in that state for a long time, it absorbs moisture inside the paper feed tray (particularly LCT (Large, which is a paper feed tray that accommodates a large capacity). The paper in (Capacity Tray) tends to be left in the apparatus for a long time). This is because the inside air of the paper feed tray is not completely blocked from the outside air of the apparatus main body. To block the inside of the paper feed tray from the outside air, it is sufficient to seal the part (gap) that communicates with the outside air of the paper feed tray. However, the paper feed tray must be pulled out to a position where paper can be supplied via a slide mechanism. is there. However, since a design gap exists between the paper feed tray that is the movable part and the apparatus main body that is the non-movable part, it is difficult to eliminate the gap.

  Therefore, in order to eliminate the gap as much as possible, a seal member made of an elastic material such as sponge or rubber is attached to a portion that communicates with the outside air on the paper feed tray side or the device main body side, and when the paper feed tray is attached to the device main body, There is a method of maintaining the sealing performance of the paper feed tray by elastically deforming and crushing the seal member.

Conventionally, as a measure to prevent moisture from the paper, a heater has been placed under the bottom plate of the paper tray in the main body of the machine so that it can exert a strong heating effect only on the area around the paper. A method of performing dehumidification with respect to this part has been proposed (see, for example, Patent Document 1).
JP-A-5-338833

  However, the method of adhering the elastic seal member to a portion that communicates with the outside air on the paper feed tray side or the apparatus main body side expands the sealed portion as the capacity of the paper feed tray increases, and the seal member accordingly. The length of the slab increases, and the amount of crushing increases. For this reason, when the user pushes the paper feed tray into the main body of the apparatus, a large number of seal members must be pushed at once, which causes problems such as poor loading, and conversely, an extra load must be applied when pulling out the paper feed tray. Occurs. In addition, the method of arranging the heater increases the cost from the viewpoint of electric energy, temperature management, and the like, and causes a problem of increasing the burden on the user.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet feeding device provided with an outside air opening / closing mechanism capable of reducing an increase in load as much as possible when a sheet feeding tray is mounted and pulled out.

  The above object is achieved by the following configuration.

  A paper feed tray on which a transfer material is stacked, a housing case in which the paper feed tray can be housed or pulled out by a sliding operation, and a seal member for blocking outside air provided in a gap between the paper feed tray and the housing case In the sheet feeding device in which the sheet feeding tray is housed in the housing case, the seal member is in pressure contact with the sheet feeding tray or the housing case by elastic deformation, and is housed or pulled out. Therefore, the sheet feeding device has an outside air blocking mechanism for separating the seal member from the sheet feeding tray or the housing case during the sliding operation.

  According to the present invention, the transfer material loaded on the paper feed tray can be shielded from outside air as much as possible, and the slide load during the operation of storing and pulling the paper feed tray into the apparatus main body is reduced.

  Hereinafter, an example of an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  The terminology used in this specification does not limit the technical scope of the invention.

  FIG. 1 is a schematic diagram illustrating an example of the overall configuration of an image forming apparatus including a printer.

  In the figure, 10 is a photoconductor as an image forming body, 11 is a charging device as charging means, 12 is an exposure optical system as image writing means, 13 is a developing device as developing means, and 14 is a surface of the photosensitive body 10. 15 is a cleaning blade, 16 is a developing sleeve, 17 is a transfer pole as a transfer means, 18 is a separation pole as a means for separating the transfer material from the photosensitive member 10, and 19 is a photosensitive material for the transfer material. This is a separation claw for preventing the body 10 from being wound. The photoconductor 10, the charging device 11, the exposure optical system 12, the developing device 13, the transfer electrode 17, the separation electrode 18, the separation claw 19, the cleaning device 14, and the like constitute the image forming unit 1.

  The photoreceptor 10 is formed by forming a photosensitive layer such as a conductive layer, an a-Si layer, or an organic photosensitive layer (OPC) on the outer periphery of a cylindrical metal base formed of, for example, an aluminum material, and the conductive layer is grounded. It is rotated in the clockwise direction indicated by the arrow in the figure.

  20 is a transport belt having a plurality of holes, 21 is a driving roller, 22 is a driven roller, and 23 is a suction box. A plurality of holes are formed in a surface contacting the transport belt 20, and a duct (not shown) The transfer material P is connected to a suction fan or the like and sucks the transfer material P onto the traveling transport belt 20. The conveying means 2 is formed by the conveying belt 20, the driving roller 21, the driven roller 22, the suction box 23, and the like.

  3 is a paper feed unit, 31 is a delivery roller, 32 is a conveyance roller pair, 33 is an entrance roller pair, 34 is a timing roller pair, 4 is a fixing device, 41 is a heat fixing roller, 42 is a pressure roller, and 7 is an image reading unit. Indicates. Reference numeral 5 denotes a paper feeding device that can accommodate a large amount of transfer material, and accommodates A, B, and C paper feeding trays. Each of the paper feed trays A, B, and C is engaged with the housings 5A, 5B, and 5C, and has an outside air opening / closing device 50 that is an outside air blocking mechanism that blocks outside air as much as possible. Details of the housing will be described later.

  Next, the image forming process will be described with reference to FIG.

  When a drive motor (not shown) starts rotating due to the start of image formation (recording), the photoconductor 10 rotates clockwise as indicated by an arrow. At the same time, application of a potential to the photoconductor 10 is started by the charging device 11.

  Image writing of an electrical signal corresponding to the image data from the image reading device 7 is started through the exposure optical system 12 on the photosensitive member 10 after the potential is applied, and the original image is applied to the surface of the photosensitive member 10. An electrostatic latent image is formed, and the electrostatic latent image is reversely developed by the developer conveyed by the developing sleeve 16 of the developing device 13 to become a toner image (visible image).

  On the other hand, when the transfer material P is supplied from the paper feed tray 3 accommodated in the machine, the transfer material P is fed by the feed roller 31 and is conveyed to the timing roller 34 pair through the pre-registration roller 38 and the conveyance roller pair 32. The toner image is synchronized with the toner image on the photoconductor 10, sent out by driving the timing roller pair 34, and fed to the region S between the transfer pole 17 and the photoconductor 10.

  Even in the case of paper feeding from the paper feeding device 5, the transfer material P of the paper feeding tray A (or B, C) is fed by the feeding roller 51, passes through the double feed prevention paper feeding roller pair 52, and then the conveying roller pair 53. Then, the toner is conveyed from the inlet roller pair 33 to the timing roller 34 via a guide plate (not shown), synchronized with the toner image on the photoconductor 10, sent out by driving the timing roller 34, and the transfer pole 17. The sheet is fed to the area S between the photosensitive member 10 and the photosensitive member 10.

  The toner image is transferred onto the transfer material P by a transfer pole 17 to which a voltage having a polarity opposite to that of the toner is applied.

  Thereafter, the photosensitive member 10 continues to rotate, is cleaned by the cleaning device 14, and is directed to the next image formation.

  On the other hand, the transfer material P on which the toner image is placed is subjected to a neutralization action by an AC voltage at the separation pole 18, the adsorption force with the photoconductor 10 is weakened, and the curvature is separated from the photoconductor 10. Note that the separation claw 19 is provided in consideration of the case where the transfer material P is wound around the photoconductor 10 due to environmental humidity or the like.

  The separated transfer material P is sent to the conveying means 2, sucked by the conveying belt 20 by the suction box 23, and conveyed to the fixing device 40. Thereafter, the transfer material P is melted and fixed on the transfer material P by applying heat and pressure while being nipped and conveyed at the nip T between the heat fixing roller 41 and the pressure roller 42. The fixed transfer material P is discharged to a discharge tray 71 by a fixing discharge roller 43.

  The mechanism for blocking the outside air of the paper feed tray according to the present invention will be described below.

  As described above, if left in the paper feed tray for a long time, moisture inside the paper feed tray is absorbed and curling is likely to occur, leading to problems such as poor paper feed and reduced electrical resistance of the paper, resulting in transfer omission.

  This problem can be avoided by preventing outside air from entering the paper feed tray as much as possible.

  The first embodiment of the present invention is a sheet feeding device provided with a mechanism for preventing as much as possible outside air from entering into a housing case that houses a sheet feeding tray.

  FIG. 2 shows an example of a paper feeding device provided with an outside air blocking mechanism provided in the housing case and the paper feeding tray.

  Note that although the housing 5C has been described as an example, the same mechanism can be applied to the housings 5A and 5B.

  FIG. 2A is a cross-sectional view as viewed from the direction of arrow X (see FIG. 1) in a state in which the paper feed tray C is pulled out from the housing 5C.

  FIG. 2B is a cross-sectional view of the state in which the paper feed tray is housed in the housing 5c as viewed from the direction of the arrow X.

  FIG.2 (c) is sectional drawing seen from the arrow Z direction of Fig.2 (a).

  FIG.2 (d) is the top view seen from the arrow Y direction of Fig.2 (a).

  FIG. 3 is an enlarged perspective view of the swing support plate and the cam plate of the seal member.

  FIG. 3A shows a swing support plate, and FIG. 3B shows a cam plate.

  2A is a diagram showing a state in which the paper feed tray C is pulled out from the housing 5C to the front side. An outside air opening / closing device 50 having a function of blocking outside air is attached to the housing 5C. The outside air opening / closing device 50 includes a swing plate 501, an elastic seal member 502, a support shaft 503, a pressure spring 504 having one end fixed to the inner surface of the housing 5C, and the support shaft 503 is housed at both ends. The swing plate 501 is supported by a bearing (not shown) integrated with the housing 5C, and rotates by receiving a force in a direction away from the inner surface of the housing 5C by a pressing spring 504 with the support shaft 503 as a fulcrum. The paper feed tray C is attached to a tray front plate 507 corresponding to the front lid of the housing 5C, a guide rail 508 is laid on the bottom surface S4 of the paper feed tray C, and is provided on the lower inner surface of the housing 5C. In addition, it can be taken in and out via a handle 510 along a rail 509 disposed on a support base (not shown). Further, cam plates 505 that are cam members that engage with the cam followers F integrated with the swing plate 501 are disposed on the four surfaces (the rear side surface S1, the upper surface S2, the front side surface S3, and the bottom surface S4) of the paper feed tray C. Has been.

  That is, in the state in which the paper feed tray C is pulled out from the housing 5C (see FIG. 2A), the cam follower F is in contact with the portion a of the cam plate 505, so that the swing plate 501 is a seal member. The cam follower F slides a part of the cam plate 505 against the pressing spring 504 except for the sliding resistance applied to the seal member 502 by separating the 502 from the outer surface of the paper feed tray C.

  In a state where the paper feed tray C is completely accommodated in the housing 5C (see FIG. 2B), the cam follower F slides on the portion b of the cam plate 505, and at the same time, the swing plate 501 The seal member 502 is rotated by a spring 504 so as to press-contact the outer surface of the paper feed tray C.

  Such an outside air opening / closing device is arranged on the four side surfaces (the rear side surface S1, the upper surface S2, the front side surface S3, and the bottom surface S4) of the paper feed tray C, and when the paper feed tray C is set in the housing case, It is possible to prevent the outside air entering through a slight gap between the tray front plate 507 and the housing 5c as much as possible and prevent moisture on the loaded transfer material. An elastic member 512 for eliminating a gap with the housing 5C is attached to the swing shaft 501 on the support shaft 503 side in the support shaft direction so as to block outside air entering through the gap as much as possible. Further, when the slide operation of pulling out and storing the paper feed tray C is performed, the seal member 502 is separated from the four side surfaces of the paper feed tray C by the action of the cam plate 505, so that the slide load is reduced and the burden on the user is reduced. Can do.

  In the first embodiment, the seal member is held, but the outside air opening / closing mechanism is provided on the housing case side so as to be in pressure contact with the paper feed tray when housed (when paper can be fed). As shown in FIG. 4 (see FIG. 4), the outside air opening / closing mechanism may be provided on the paper feed tray side.

  FIG. 4 is a view showing an outside air opening / closing mechanism provided on the sheet feeding tray side. However, the members having the same functions as those in the configuration of FIG.

  FIG. 4A shows a cross-section in a state where the paper feed tray C is housed in the housing 5C.

  FIG. 4B shows a cross section in a state in which the paper feed tray C is pulled out from the housing 5C.

  In FIG. 4, an outside air opening / closing device 60 having a function of blocking outside air is attached to the paper feed tray C. The outside air opening / closing device 60 includes a swing plate 601, an elastic seal member 602, a support shaft 603, a pressing spring 604 whose one end is fixed to the outer surface of the paper feed tray C, and the like. The swing plate 601 is supported by a bearing (not shown) integral with the paper tray C, and is rotated in a direction in which the seal member 602 is pressed against the inner surface of the housing 5C by a pressing spring 604 with the support shaft 603 as a fulcrum. . The paper feed tray C is attached to a tray front plate 507 corresponding to the front lid of the housing 5C, a guide rail pair 508 is laid on the bottom surface S4 of the paper feed tray C, and is provided on the lower inner surface of the housing 5C. It can be taken in and out via a handle 510 along a rail 509 disposed on a support base (not shown). A cam plate 605 that engages with the cam follower F of the shielding member swinging device 60 is disposed on the four inner surfaces of the housing 5C.

  That is, when the paper feed tray C is pulled out of the housing case 5C from the state where the paper feed tray C is completely housed in the housing 5C, the cam follower F resists the pressing spring 604 and c of the cam plate 605. The sliding plate 601 separates the seal member 602 from the inner surface of the housing, so that the sliding resistance applied to the seal member 602 is eliminated, and the cam follower F slides the d and e portions of the cam plate. The seal member 602 comes out of the housing 5C. At this time, the rocking plate 601 is rotated by a predetermined angle by a stopper (not shown) and stopped. Conversely, when the paper feed tray C is accommodated in the housing 5C, the cam follower F is engaged with the e portion of the cam plate 605 and the seal member 602 is inserted in a state of being separated from the inner surface of the housing 5C. The rocking plate 601 is rotated toward the inner surface of the housing 5C by the pressing spring 504 at the same time as it slides to the portion c through the parts d, e, d, and presses the seal member 602 against the inner surface of the housing 5C. . Such outside air opening and closing devices are arranged on the four surfaces of the paper feed tray C. In this way, it is possible to prevent the outside air entering through a slight gap between the tray front plate 507 and the housing 5C as much as possible and prevent moisture on the loaded transfer material. Note that an elastic member 612 for eliminating a gap with the paper feed tray is attached to the support shaft 603 side of the swing plate 601 in the direction of the support shaft to block outside air entering from the gap as much as possible. Further, when the paper tray C is pulled out and accommodated, the seal member 602 is separated from the inner surface of the accommodating housing 4 by the action of the cam plate 605, so that the sliding load is reduced and the burden on the user is reduced. it can.

1 is a schematic diagram illustrating an example of an overall configuration of an image forming apparatus including a printer. An example of a sheet feeding device provided with an outside air blocking mechanism provided in a housing and a sheet feeding tray is shown. It is the perspective view which expanded the rocking | fluctuation support plate and cam plate of the sealing member. It is a figure which shows the external air opening / closing mechanism provided in the paper feed tray side.

Explanation of symbols

5 Paper feeding device 50, 60 Outside air opening / closing device 50
51 Feed rollers 501 and 601 Swing plates 502 and 602 Seal members 503 and 603 Support shafts 504 and 604 Press springs 505 and 605 Cam plates 507 Front tray plates 508 Guide rails 509 Rails 510 Handles

Claims (2)

A paper feed tray on which a transfer material is stacked, a housing case in which the paper feed tray can be housed or pulled out by a sliding operation, and a seal member for blocking outside air provided in a gap between the paper feed tray and the housing case In the sheet feeding device in which the sheet feeding tray is housed in the housing case, the seal member is in pressure contact with the sheet feeding tray or the housing case by elastic deformation, and is housed or pulled out. Therefore, the sheet feeding device has an outside air blocking mechanism for separating the seal member from the sheet feeding tray or the housing case during the sliding operation. One of the paper feed tray and the housing case is provided with a cam member, and the other is provided with a cam follower. The seal member is attached to a holding member integral with the cam follower and can swing. 2. The outside air blocking mechanism in which the seal member is pressed against or separated from either the sheet feed tray or the housing case by a swinging operation by engagement between the member and the cam follower. Paper feeder.

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