JP4597212B2 - Sheet stacking apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, a multifunction machine, an image reader, a sorter, and a finisher, an original reading apparatus, and a sheet processing apparatus. In particular, the present invention relates to a sheet stacking apparatus for discharging and stacking sheets and an image forming apparatus including the sheet stacking apparatus.

  2. Description of the Related Art Conventionally, in a sheet stacking device provided in an image forming apparatus such as a copying machine, a laser printer, a facsimile, etc., a stacking base is provided so that sheets discharged from a discharge port formed on the upper part of the apparatus main body can be stacked. The sheet stacking apparatus is known and is in practical use. The invention described in Patent Document 1 is proposed as an invention relating to such a sheet stacking apparatus.

  In the invention described in Patent Document 1, the sheet stacking device is provided in the upper part of the image forming apparatus main body. According to such a configuration, since the space above the image forming apparatus main body is used, the space for the sheet stacking apparatus can be reduced, and at the same time, the user can easily handle the stacked sheets. Also excellent.

JP 2002-145503 A

  However, in the above-described conventional sheet stacking apparatus, since the sheet discharge port is exposed to the outside, the operation noise of the drive motor and the like generated inside the image forming apparatus main body is released through this discharge port, so that noise is generated. It was a factor that increased. In addition, since a stacking tray for stacking discharged sheets is provided outside the image forming apparatus main body, noise during sheet discharge is a noise source. Further, the rubbing noise of discharged sheets and already stacked sheets has become a noise source.

  In view of this, the present invention provides an operation sound of the image forming apparatus discharged from the discharge port, a sound of the sheet when the sheet is discharged, and a sound of the sheet when the discharged sheet is rubbed against the already loaded sheet. An object of the present invention is to provide a sheet stacking apparatus and an image forming apparatus that are difficult to leak to the outside.

To achieve the above object, according to the present invention, a discharge port for discharging the sheet is formed on the upper surface of the instrumentation Okimoto body, and a first tray for stacking sheets discharged from the discharge port in the sheet stacking apparatus, the stacked a first position facing the first tray above from the outlet, it is supported on the upper surface of the front KiSo Okimoto body, luciferyl over preparative discharged from the discharge port 2 A second stacking tray that can be switched to a position, and the second stacking tray is disposed at the first position when a sheet having a predetermined discharge direction length is discharged, and the predetermined discharge direction length. sheet stacking apparatus according to claim Rukoto disposed in said second position is provided when the long sheet discharge direction length is discharged than is.

  As described above, according to the present invention, when the second stacking tray is switched to the first position, the second stacking tray can cover the discharge port and the sheet. As a result, the operation sound of the sheet stacking device released from the discharge port, the sound of the sheet when the sheet is discharged, and the sound of the sheet when the discharged sheet rubs against the already stacked sheet leaks to the outside It becomes difficult to do.

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of a laser beam printer (hereinafter referred to as “image forming apparatus 100”) as an example of an image forming apparatus according to the first embodiment of the present invention. The image forming apparatus 100 includes a deck 101 that stores a recording sheet P as a “sheet” that is a “sheet”, and includes a pickup roller 102 that feeds the recording sheet P out of the deck 101. Further, the image forming apparatus 100 includes a deck sheet feeding roller 103 that conveys the recording sheet P fed by the pickup roller 102, and a retard that forms a pair with the deck sheet feeding roller 103 to prevent double feeding of the recording sheet P. A roller 104 is provided.

  A recording sheet P is transported downstream of the deck sheet feeding roller 103 in the transport direction of the recording sheet P to the deck 101 and further downstream in the transport direction of the recording sheet P (hereinafter simply referred to as “downstream”). A paper feeding / conveying roller 105 is provided. Further, a registration roller pair 106 that conveys the recording sheet P in synchronization with the image forming operation is disposed on the downstream side.

  Further, downstream of the registration roller pair 106, a process cartridge C constituting an image forming unit that forms a toner image on the photosensitive drum 108 based on a laser beam from a laser scanner unit 107 (to be described later) is provided in the main body of the image forming apparatus. On the other hand, it is detachably mounted.

  The process cartridge C is provided with a rotatable photosensitive drum 108, a charging roller 109, a developing device 110, and a cleaning device (not shown) around it. At the time of image formation, the surface of the photosensitive drum 108 is uniformly charged by the charging roller 109 and a latent image is formed by selective exposure from the laser scanner unit 107. Develop to make visible image. Then, by applying a transfer bias voltage to the transfer roller 111, the toner image is transferred to the recording sheet P that has been conveyed to form an image. Further, downstream of the transfer roller 111, a conveyance guide 112 and a fixing device 113 that thermally fixes the toner image transferred onto the recording sheet P are provided.

  The fixing device 113 includes a heating roller 119a that is a rotating body having a heating body 118 (halogen heater) therein, and a pressure roller 119b that is a rotating body that presses the heating roller 119a. Further, the fixing device 113 includes a sheet separating device 117 in the vicinity of the downstream side of the pressure contact portion between the heating roller 119a and the pressure roller 119b.

  The recording sheet P that has passed through the press contact portion is sent to the discharge roller 115 by the conveying roller pair 114. The sheet on which images or characters are printed by such a series of image forming processes is then discharged to the first stacking tray 121 formed on the upper portion of the image forming apparatus 100 via the discharge port 116 by the discharge roller 115. Loaded.

  Next, the configuration of the sheet stacking device 120 provided integrally with the image forming apparatus 100 will be described with reference to FIGS. FIG. 2 is a cross-sectional view showing an outline of the configuration of the sheet stacking device 120, and FIG. 3 is a plan view of the sheet stacking device 120. FIG. 4 is a cross-sectional view showing the operation of the sheet stacking device 120.

  As shown in FIG. 2, a convex cover portion 131 that covers the discharge roller 115 that discharges the recording sheet P is formed on the upper portion of the sheet stacking device main body 120 a of the sheet stacking device 120. A flat surface portion 133 is formed on the upper surface of the sheet stacking apparatus main body 120a so as to be continuous with the lower portion of the side surface 132 of the cover portion 131 and spread in a flat shape. A first stacking tray 121 is defined on the side of the flat portion 133 close to the discharge port 116. A receiving surface 134 that extends to a position lower than the first stacking tray 121 and that can receive the second stacking tray at the second position is extended to the side farther from the discharge port 116 of the first stacking tray 121. Further, a step portion 131b is formed at a corner where the upper surface portion 131a and the side surface 132 of the cover portion 131 intersect. As will be described later, the step portion 131b can receive the second stacking tray at the first position.

  A discharge port 116 for discharging the recording sheet P is formed on the side surface 132 of the cover portion 131 at a position adjacent to the discharge roller 115. The aforementioned first stacking tray 121 is formed below the discharge port 116 and stacks the recording sheets P discharged from the discharge port 116. A columnar support portion 100 a is formed from the surface of the receiving surface 134. A hole 100b is formed in the support portion 100a.

  In addition, a second stacking tray 122 is provided above the discharge port 116 so as to face the first stacking tray 121 and cover the recording sheet P discharged from the discharge port 116. In the first position, the second stacking tray 122 is positioned above the discharge port 116 and can cover the first stacking tray 121. A support portion 122 a is formed on one end side of the second stacking tray 122. A support shaft 123 is formed in a convex shape on the support portion 122a. The support shaft 123 is arranged so as to be orthogonal to the discharge direction of the recording sheet P. A support shaft 123 is inserted into the hole 100b, the second stacking tray 122 is rotatably supported by the support shaft 123, and the second stacking tray 122 is configured to be rotatable about the support shaft 123 (see FIG. 3). In the second position, a sheet stacking surface 122 b that is a “recording material stacking surface” is formed on the second stacking tray 122 so as to face the first stacking tray 121. The second stacking tray 122 functions as an extension tray that is temporarily used when stacking a large size recording sheet P that is longer in the conveyance direction of the recording sheet P than a small size sheet.

  Normally, when a small-sized recording sheet P1 that is used as a standard and has a predetermined length in the conveyance direction is printed, the recording sheet P1 is discharged from the discharge port 116 as shown in FIG. It is loaded on the surface of the tray 121. At this time, there are an operating sound S1 emitted from the discharge port 116, a sound S2 generated when the recording sheet P1 is discharged, and a rubbing sound S3 generated by rubbing with the recording sheet P1 already stacked. appear. These sounds are a major factor in increasing the noise level of products.

  When the second stacking tray 122 is switched to the first position facing the first stacking tray 121, the second stacking tray 122 can cover the discharge port 116 and the recording sheet P1. As a result, the operation sound S1 of the sheet stacking device 120 discharged from the discharge port 116 can be made difficult to leak outside. Further, a sound S2 of the recording sheet P generated when the recording sheet P1 is discharged, a rubbing sound S3 generated by rubbing with the recording sheet P2 on which the discharged recording sheet P1 is already stacked, and the like. It is possible to block the sound emitted upward and make it difficult to leak out.

  Further, when the second stacking tray 122 is disposed at the first position, the step portion 131b receives the end of the second stacking tray 122. Then, since the side surface 132 and the second stacking tray 122 are continuous, the soundproofing effect is improved when the image forming apparatus main body and the second stacking tray 122 are continuous.

  Further, when the second stacking tray 122 rotates around the support shaft 123 and is disposed at the first position, the second stacking tray 122 is disposed to face the first stacking tray 121, so that the second stacking tray 122 The tray 122 does not require a required area or place in a direction parallel to the horizontal plane.

  Next, as shown in FIG. 2, when the second stacking tray 122 in the first position rotates in the direction of arrow A about the support shaft 123 and reverses, as shown in FIG. It is supported on the upper surface of the sheet stacking apparatus main body 120a and switched to the second position where the sheets can be stacked.

  When the sheet stacking surface 122b of the second stacking tray 122 appears on the upper side, the second stacking tray 122 is disposed adjacent to the first stacking tray 121 so that the sheet stacking surface 122b extends in the discharge direction of the recording sheet P1. Expanded. Accordingly, it is possible to stack a large size recording sheet P3 that is longer in the transport direction than a small size sheet. Since the leading edge of the recording sheet P3 is prevented from dropping down or the recording sheet P3 is dropped, the stackability and alignment of the recording sheets P3 are improved. Also, the stacking area of the recording sheets P3 can be expanded only when it is desired to discharge the recording sheet P3 that is long in the discharging direction of the recording sheet P3.

  When the second stacking tray 122 is switched to the second position, the cover of the sheet stacking device main body 120a is configured so that the second stacking tray 122 is in close contact with the surface of the receiving surface 134 adjacent to the first stacking tray 121. Will increase. Accordingly, the effect of blocking the operating sound S4 generated inside the image forming apparatus 100 is increased, and the sound pressure released to the outside of the sheet stacking apparatus main body 120a is reduced.

(Second Embodiment)
Next, a sheet stacking apparatus according to the second embodiment will be described with reference to FIGS. In addition, about the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 5 and 6, a first stacking tray 121 for stacking small sizes is formed on the upper surface of the sheet stacking apparatus main body 120a, and a second stacking tray 130 is attached to the sheet stacking apparatus main body 120a. The second stacking tray 130 is a tray on which a large size recording sheet P1 that is longer in the conveyance direction of the recording sheet P1 than a small size is stacked. A support shaft 130 a is formed on the inner side of the base end of both arms of the second stacking tray 130. The support shaft 130a is arranged so as to be orthogonal to the discharge direction of the recording sheet P. Further, on the surface of the second stacking tray 130, a sheet stacking surface 130b that is a “recording material stacking surface” for stacking the recording sheets P1 discharged from the discharge port 116 is formed. On the other hand, a hole 200b is formed on the side surface of the sheet stacking apparatus main body 120a. Since the support shaft 130a is inserted into the hole 200a, the second stacking tray 130 is supported so as to be swingable about the support shaft 130a.

  Further, locking claws 130 c as locking means are formed on both arms of the second stacking tray 130. A hole 200b and a hole 200c for inserting the locking claw 130c are formed in the side wall of the sheet stacking apparatus main body 120a. The hole 200b is formed at substantially the same height as the support shaft 130a, and the hole 200c is formed at a position higher than the support shaft 130a.

  When the locking claw 130c enters the hole 200c, the second stacking tray 130 is held at the first position located above the discharge port 116. Further, when the locking claw 130c enters the hole 200b, the second stacking tray 130 is held at the second position in close contact with the stacking surface of the first stacking tray 121 (the upper surface of the sheet stacking device main body 120a). In addition, the structure which used the damper with a friction effect | action for the rocking | swiveling center part instead of the above-mentioned latching claw 130c may be sufficient.

  As shown in FIG. 5, when printing and discharging a recording sheet P <b> 1 (small size paper) of a predetermined transport direction length that is used as a standard, the second stacking tray 130 is the second stack tray 130 above the discharge port 116. Switch to 1 position. At this time, as described in the first embodiment, the second stacking tray 130 covers the discharge port 116 and the recording sheet P1. As a result, the operation sound S1 of the sheet stacking device 129 discharged from the discharge port 116 can be prevented from leaking outside. Further, the sound S2 of the recording sheet P1 generated when the recording sheet P1 is discharged, the rubbing sound S3 generated by the rubbing with the recording sheet P2 when the discharged recording sheet P1 is already stacked, etc. It is possible to block the sound radiated to the outside and make it difficult to leak out.

  On the other hand, when discharging a large size recording sheet P3 whose length in the conveyance direction of the recording sheet P1 is longer than that of the small size paper, the second stacking tray 130 swings in the direction of arrow B in FIG. Then, as shown in FIGS. 6 and 7, the second stacking tray 130 is switched to the second position. In the second position, a large size recording sheet P3 longer than the small size paper is stacked on the sheet stacking surface 130b of the second stacking tray 130. In this case, the leading edge of the recording sheet P3 is prevented from dropping downward or the recording sheet P3 is prevented from dropping, so that the stackability and alignment of the sheets are improved.

  Further, when the second stacking tray 130 is switched to the second position shown in FIG. 7, the second stacking tray 130 is brought into close contact with the first stacking tray 121 and the thickness of the cover of the sheet stacking apparatus main body 120a is increased. . As a result, the effect of blocking the operating sound S4 generated inside the image forming apparatus 100 is increased, and the sound pressure released to the outside of the sheet stacking apparatus main body is reduced.

  In the second embodiment described above, the second stacking tray 130 is used as an extension tray. However, the second stacking tray 130 may be configured to be used as an auxiliary tray for sorting stacked sheets.

  As shown in FIG. 8, when the second stacking tray 130 is rotated about the support shaft 130a and disposed at the second position, the sheet stacking surface 130b of the second stacking tray 130 is directed upward. The second stacking tray 130 is loaded with the recording sheets P5. In a state where the recording sheet P5 already printed is stacked on the sheet stacking surface 130b of the second stacking tray 130, the second stacking tray 130 swings around the support shaft 130a and is above the discharge port 116. It is switched to 1 position (two-dot chain line). Since the sheet stacking surface 130b of the second stacking tray 130 is directed upward, the second stacking tray 130 can be disposed at the first position in a state where the recording sheets P5 are stacked. Then, the recording sheet P <b> 6 discharged later is stacked on the surface of the first stacking tray 121 positioned below the second stacking tray 130. In this way, the recording sheet P6 to be printed later is easily sorted and convenience is improved.

  When an image forming apparatus is shared and used by a large number of people using a network, it is often necessary to search for and retrieve the sheet output by the user from among the stacked sheets. If someone else's job starts and prints while you are looking for the output sheet, you must wait until the job is finished. Alternatively, if an act of searching for a sheet output from the stacking tray without waiting for completion of printing is performed, the next sheet is prevented from being discharged, and curling or jamming may occur. Therefore, when the second stacking tray 130 is used for sorting sheets, it is convenient for handling discharged and stacked sheets.

  In the first embodiment and the second embodiment, the configuration in which the second stacking trays 122 and 130 are rotated or swinged as extension trays and the position is switched is shown. However, the second stacking trays 122 and 130 are detachable. It may be a configuration. According to such a configuration, the second stacking trays 122 and 130 can be mounted on the sheet stacking device main body 120a when necessary.

  The second stacking trays 122 and 130 shown in the first embodiment and the second embodiment may be formed of a member having a high sound transmission loss of 10 dB or more such as glass. According to such a material, the sound insulation effect of the second stacking trays 122 and 130 is improved. Further, the second stacking trays 122 and 130 may be formed of a member having a high sound absorption coefficient of 0.1 or more, such as a fiber or a foam material. According to such a configuration, the sound absorption effect of the second stacking trays 122 and 130 is improved. Further, the second stacking trays 122 and 130 may be formed of a member having a loss factor of 0.01 or more such as a damping material. According to such a configuration, the vibration damping effect of the second stacking trays 122 and 130 is improved. Alternatively, the sound insulation, sound absorption, and vibration suppression characteristics of the second stacking trays 122 and 130 may be further improved by using the above-described material as a part of the second stacking trays 122 and 130.

  In the first embodiment and the second embodiment, the configuration of manually switching the positions of the second stacking trays 122 and 130 has been described. However, the configuration of automatically switching the second stacking trays 122 and 130 is described. Also good. For example, a normal image forming apparatus includes a detecting unit that detects the length in the conveyance direction of the recording sheet P1 used for printing. The second stacking trays 122 and 130 may include automatic position switching means that is “switching means” that automatically moves using a drive source such as a motor or a solenoid. According to such a configuration, it is possible to automatically switch the positions of the second stacking trays 122 and 130 based on the detection signal obtained from the detection means, and the operability is further improved. Then, a sheet having a predetermined conveyance direction length used as a standard is automatically stacked on the first stacking tray 121 by the function of the detection unit and the automatic position switching unit, and the sheet having a large conveyance direction length is used. Can be stacked on the second stacking trays 122 and 130.

  In the first and second embodiments, the second stacking trays 122 and 130 suppress upward sound propagation. In addition, it is also possible to attach a sound blocking cover for blocking the transmission of sound in the lateral direction to the second stacking trays 122 and 130.

  In the first embodiment and the second embodiment, the configuration in which the sheet stacking apparatus according to the present invention is integrally incorporated in the image forming apparatus has been described. However, for example, the sheet stacking apparatus is provided separately from the image forming apparatus. The present invention is effective even when applied to a finisher that performs predetermined processing.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention. 1 is a cross-sectional view illustrating a schematic configuration of a sheet stacking device included in an image forming apparatus. 3 is a plan view of the sheet stacking apparatus. FIG. FIG. 10 is a cross-sectional view illustrating the operation of the sheet stacking apparatus. FIG. 6 is a cross-sectional view illustrating a schematic configuration of a sheet stacking apparatus included in an image forming apparatus according to a second embodiment of the present invention. 3 is a plan view of the sheet stacking apparatus. FIG. FIG. 10 is a cross-sectional view illustrating the operation of the sheet stacking apparatus. FIG. 10 is a cross-sectional view illustrating the operation of the sheet stacking apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 120 Sheet stacking apparatus 120a Sheet stacking apparatus main body 100a Support part 116 Ejection port 129 Sheet stacking apparatus 121 First stacking tray 122, 130 Second stacking tray 122b, 130b Sheet stacking surface 123, 130a Support shaft 131b Stepped part P1 Recording sheet

Claims (7)

A discharge port for discharging the sheet is formed on the upper surface of the instrumentation Okimoto body, the sheet stacking apparatus having a first tray for stacking sheets discharged from the discharge port,
A first position facing the first tray above from the outlet, is supported on the upper surface of the front KiSo Okimoto body, switchable and a second position for stacking Cie over preparative discharged from the discharge port A second loading tray ,
The second stacking tray is disposed at the first position when a sheet having a predetermined discharge direction length is discharged, and a sheet having a discharge direction length longer than the predetermined discharge direction length is discharged. sheet stacking apparatus according to claim Rukoto disposed in said second position when. The second tray is rotatably supported between the first position and the second position around a support shaft perpendicular to the discharge direction of the sheet over preparative, sheet stacking surface of said second tray is The second stacking tray is directed downward when the second stacking tray is disposed at the first position, and is directed upward when the second stacking tray is disposed at the second position. The sheet stacking apparatus described in 1. The second tray is rotatably supported between the first position and the second position around a support shaft perpendicular to the discharge direction of the sheet over preparative, sheet stacking surface of said second tray is 2. The sheet stacking apparatus according to claim 1, wherein the second stacking tray is directed upward regardless of whether the second stacking tray is disposed at the first position or the second position. Detection means for detecting a discharge direction length of the sheet to be discharged, automatically switch the switching means the second tray on the basis of the detection signal to one of said first position or said second position of said detecting means The sheet stacking apparatus according to claim 1, further comprising: The second tray, the front KiSo Okimoto sheet stacking apparatus according to any one of claims 1 to 4, characterized in that it is detachable from the body. Image forming means for forming an image on a sheet, the image forming apparatus characterized by comprising a, a sheet stacking apparatus according to any one of claims 1 to 5 for stacking sheets having images formed. An image forming means for forming an image on a sheet and the sheet stacking apparatus according to claim 1 for stacking the image-formed sheet, and formed on an upper surface of the image forming apparatus main body above the discharge port. , images forming device you further comprising a stepped portion for receiving an end portion of said second tray when said second tray is disposed in the first position.

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