Sheet accommodating device and image forming apparatus

Abstract

Provided is a sheet accommodating device and an image forming apparatus, the sheet accommodating device including: a sheet accommodating body that accommodates a sheet and is attached to an apparatus main body so as to be capable of being pulled out and drawn in; an engagement mechanism provided to either the apparatus main body or the sheet accommodating body; and a pull-in mechanism provided on the other one of the device main body and the sheet accommodating body, the pull-in mechanism having a guide groove that is engaged with the engagement mechanism and guides a pull-in operation of the sheet accommodating body, and the guide groove being provided with a resistance acting portion that causes a resistance to act on the pull-in operation of the sheet accommodating body.

Description

Technical Field

[0001] This invention relates to a sheet receiving device and an image forming device. Background Technology

[0002] Previously, technologies related to sheet receiving devices, such as those disclosed in Patent Document 1 and Patent Document 2, have been proposed.

[0003] In Patent Document 1, the groove of the guide mechanism is composed of a straight section parallel to the installation direction of the sheet receiving mechanism and a curved section provided downstream of the straight section in the installation direction and bent toward the swing fulcrum of the pull-in mechanism.

[0004] In Patent Document 2, the forming range of the inlet opening in the direction orthogonal to the sheet receiving section mounting direction is set to be the same as or less than the forming range of the guide groove in the direction orthogonal to the sheet receiving section mounting direction.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2006-151687

[0006] Patent Document 2: Japanese Patent Application Publication No. 2008-184245 Summary of the Invention

[0007] The purpose of this invention is to adjust the pulling force of the sheet container compared to a case where the guide groove of the pulling mechanism does not have a resistance part.

[0008] The invention described in Scheme 1 is a sheet receiving device, which comprises:

[0009] A sheet housing that holds the sheet and can be pulled out and pulled in and installed on the main body of the device;

[0010] The joining mechanism is disposed in either the device body or the sheet housing; and

[0011] A pull-in mechanism, disposed in another of the device body or the sheet container, has a guide groove that engages with the engagement mechanism to guide the pull-in action of the sheet container, and a resistance part is provided in the guide groove to cause resistance to the pull-in action of the sheet container.

[0012] Furthermore, resistance refers to the force exerted by another object as a reaction to the force when an object comes into contact with and applies a force to it. Here, resistance refers to the force exerted by the resistance part of the guide groove on the engagement mechanism as a reaction to the force when the engagement mechanism comes into contact with and applies a force to the resistance part of the guide groove of the pull-in mechanism.

[0013] The invention described in Scheme 2 is the sheet receiving device described in Scheme 1, wherein,

[0014] The resistance element is positioned at the beginning of the pull-in action of the guide groove onto the sheet housing.

[0015] The invention described in Scheme 3 is the sheet receiving device described in Scheme 2, wherein,

[0016] The resistance section is formed by a region that causes the guide groove to bend and / or curve in the pulling direction of the sheet housing.

[0017] The invention described in Scheme 4 is the sheet receiving device described in Scheme 3, wherein,

[0018] The resistance section is composed of a region that is bent multiple times in the pulling direction of the sheet housing.

[0019] The invention described in Scheme 5 is the sheet receiving device described in Scheme 1, wherein,

[0020] The guide groove is provided with a facilitating part to promote the pulling-in action of the sheet accommodating body.

[0021] The invention described in Scheme 6 is the sheet receiving device described in Scheme 5, wherein,

[0022] The promoting part is disposed at the end of the pulling action of the guide groove into the sheet container.

[0023] The invention described in Scheme 7 is the sheet receiving device described in Scheme 6, wherein,

[0024] The promoting section is composed of a region in which the guide groove is formed into a straight line.

[0025] The invention described in Scheme 8 is the sheet receiving device described in Scheme 5, wherein,

[0026] The guide groove has a curved portion between the resistance portion and the promoting portion, which bends in a direction that intersects with the pulling direction of the sheet accommodating body.

[0027] The invention described in Scheme 9 is the sheet receiving device described in Scheme 8, wherein,

[0028] The curved portion is formed as an arc with a specified radius of curvature.

[0029] The invention described in Scheme 10 is an image forming apparatus, comprising:

[0030] Sheet receiving mechanism, for receiving sheet; and

[0031] An image forming mechanism forms an image on the sheet.

[0032] The sheet receiving device described in any one of Schemes 1 to 9 is used as the sheet receiving mechanism.

[0033] Invention Effects

[0034] According to the first aspect of the present invention, compared with the case where there is no resistance part in the guide groove of the pull-in mechanism, the pull-in force of the sheet accommodating the device body that can be pulled out and pulled in can be adjusted.

[0035] According to the second aspect of the invention, compared to the case where the resistance part is located further back than the starting end of the pull-in action of the guide groove on the sheet container, it is possible to counteract excessive pushing force on the sheet container earlier.

[0036] According to the third aspect of the present invention, compared with the case where the guide groove is formed as a straight line in the pulling direction of the sheet container by the resistance action part, the resistance can be effectively applied to the sheet container.

[0037] According to the fourth aspect of the present invention, compared with the case where the resistance part is formed by a single bent area in the pulling direction of the sheet container, the resistance can be applied to the sheet container more effectively.

[0038] According to the fifth aspect of the present invention, compared with the case where the guide groove does not have a promoting part, the sheet container can be reliably pulled in.

[0039] According to the sixth aspect of the present invention, compared with the case where the promoting part is located upstream of the middle of the pulling action, the sheet accumulator can be reliably pulled into the predetermined position.

[0040] According to the seventh aspect of the present invention, compared with the case where the guide groove of the promoting part is formed in a curved shape, the pulling-in function can be effectively performed.

[0041] According to the eighth aspect of the present invention, compared with the case where a promoting part is continuously provided in the guide groove along with the resistance part, it is possible to smoothly transition from the effect of resistance on the sheet container to the effect of promoting force on the sheet container.

[0042] According to the ninth aspect of the present invention, compared with the case where the curved portion is formed into an arc shape with a changing radius of curvature, a substantially constant pulling force can be applied to the sheet housing.

[0043] According to the tenth aspect of the present invention, compared with the case where the sheet receiving device described in any one of aspects 1 to 9 is not used as a sheet receiving mechanism, the pulling force of the sheet receiving body that is pulled out and pulled in can be adjusted, thereby improving operability. Attached Figure Description

[0044] The embodiments of the present invention will be described in detail with reference to the following figures.

[0045] Figure 1 This is an overall structural diagram of an image forming apparatus that utilizes the sheet receiving device according to Embodiment 1 of the present invention.

[0046] Figure 2 This is a structural diagram showing the image forming section of the image forming apparatus according to Embodiment 1 of the present invention.

[0047] Figure 3 This is a perspective structural diagram showing the paper tray of the sheet receiving device according to Embodiment 1 of the present invention.

[0048] Figure 4 This is a cross-sectional structural diagram showing the main parts of the sheet receiving device according to Embodiment 1 of the present invention.

[0049] Figure 5 This is a three-dimensional structural diagram showing the sheet material receiving device.

[0050] Figure 6 This is a perspective structural diagram of the main body of the image forming apparatus to which the sheet receiving device according to Embodiment 1 of the present invention is applied.

[0051] Figure 7 This is a plan view showing the installation state of the locking pin.

[0052] Figure 8 This is a planar structural diagram showing the pull-in device.

[0053] Figure 9 This is a planar structural diagram showing the pull-in device.

[0054] Figure 10 This is a three-dimensional structural diagram representing the pull-in device.

[0055] Figure 11 This is a three-dimensional structural diagram of the bracket.

[0056] Figure 12 This is a structural diagram representing a mechanical one-way clutch.

[0057] Figure 13 This is a structural diagram showing the main parts of the existing pull-in device.

[0058] Figure 14 This is an enlarged structural diagram showing the main part of the pull-in device in the sheet receiving device according to Embodiment 1 of the present invention.

[0059] Figure 15 This is a structural diagram showing the main part of the pull-in device in the sheet receiving device according to Embodiment 1 of the present invention.

[0060] Figure 16 This is a structural diagram illustrating the operation of the pull-in device in the sheet receiving apparatus according to Embodiment 1 of the present invention.

[0061] Figure 17 This is a structural diagram illustrating the operation of the pull-in device in the sheet receiving apparatus according to Embodiment 1 of the present invention.

[0062] Figure 18 This is a structural diagram representing a comparative example.

[0063] Figure 19 This is a structural diagram showing the main part of the pull-in device in the sheet receiving device according to Embodiment 2 of the present invention.

[0064] Label Explanation

[0065] 1-Image forming apparatus, 5-Recording paper, 50-Sheet receiving device, 51-Paper supply tray, 77-Connecting pin, 80-Pull-in device, 81-Receiving box, 82-Bracket, 94-99a-Gear, 91-Guide groove, 910-Resistance action part. Detailed Implementation

[0066] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0067] [Implementation Method 1]

[0068] Figure 1 and Figure 2 This is a diagram showing an image forming apparatus that uses the sheet receiving device according to Embodiment 1. Figure 1 This provides an overall overview of the image forming apparatus. Figure 2 The magnified view shows the main parts of the image forming apparatus (image generating device, etc.). Figure 1 In the diagram, the symbol X represents the horizontal direction (width direction) of the image forming apparatus, the symbol Y represents the rear side direction of the image forming apparatus, and the symbol Z represents the vertical direction of the image forming apparatus.

[0069] <Overall Structure of the Image Forming Apparatus>

[0070] The image forming apparatus 1 according to Embodiment 1 is configured as a color copier, for example. This image forming apparatus 1 has an image reading device 2 at the upper end of the apparatus body 1a that reads an image of an original (not shown). In addition to copying the image of the original read by the image reading device 2, the image forming apparatus 1 also functions as a color printer or the like that that records image information sent from a host computer (not shown).

[0071] The image forming apparatus 1 includes, within its main body 1a, a plurality of image generating devices 10, an intermediate transfer device 20, a sheet holding device 50 as described in Embodiment 1, and a fixing device 40. The plurality of image generating devices 10 form toner images developed using a toner constituting a developer. The intermediate transfer device 20 holds each toner image formed by the image generating device 10 and ultimately transfers it to a secondary transfer position on a recording paper 5, which is an example of a sheet. The sheet holding device 50 holds and supplies the recording paper 5 to be supplied to the secondary transfer position of the intermediate transfer device 20. The fixing device 40 fixes the toner images on the recording paper 5 that have been transferred by the intermediate transfer device 20. The plurality of image generating devices 10 and the intermediate transfer device 20 constitute an image forming mechanism for forming images on the recording paper 5. Furthermore, the main body 1a of the image forming apparatus 1 is formed from support structure components and an outer casing, etc.

[0072] The image generating apparatus 10 consists of four image generating devices 10Y, 10M, 10C, and 10K, each specifically designed to generate tonal images of four colors: yellow (Y), magenta (M), cyan (C), and black (K). These four image generating devices 10 (Y, M, C, K) are arranged in a row at an angle within the internal space of the apparatus body 1a.

[0073] like Figure 1 or Figure 2 As shown, the image generating apparatuses 10 for yellow (Y), magenta (M), cyan (C), and black (K) (Y, M, C, K) each include a rotating photosensitive drum 11, which serves as an image holder for holding electrostatic latent images. Around the photosensitive drum 11 are arranged a charging device 12, an exposure device 13, a developing device 14, a primary transfer device 15, a drum cleaning device 16, etc. The charging device 12 charges the peripheral surface (image holding surface) of the photosensitive drum 11 capable of forming images to the required potential. The exposure device 13 irradiates the charged peripheral surface of the photosensitive drum 11 with light based on image information (signal) to form electrostatic latent images of each color having a potential difference. The developing device 14 develops the electrostatic latent images using a toner of the corresponding color (Y, M, C, K) developer to form toner images. The primary transfer device 15 transfers each toner image onto an intermediate transfer device 20. The drum cleaning device 16 removes and cleans toner and other residues that remain on the image holding surface of the photosensitive drum 11 after a single transfer.

[0074] The photosensitive drum 11 is formed by creating an image holding surface on the circumferential surface of a grounded cylindrical or cylindrical substrate, having a photoconductive layer (photosensitive layer) made of a photosensitive material. The photosensitive drum 11 is supported so that it is powered by a drive device (not shown) and rotates in the direction indicated by arrow A.

[0075] like Figure 2 As shown, the charging device 12 consists of a contact-type charging roller 121 arranged in contact with the photosensitive drum 11. A cleaning roller 122 for cleaning the surface of the charging roller 121 is arranged on the back side of the charging roller 121. A charging voltage is supplied to the charging roller 121 of the charging device 12. As the charging voltage, when the developing apparatus 14 is performing reverse development, a voltage or current with the same polarity as the charging polarity of the toner supplied from the developing apparatus 14 is supplied.

[0076] The exposure apparatus 13 illuminates the peripheral surface of the charged photosensitive drum 11 with light composed of image information from the original document read by the image reading device 2 or image information input to the image forming apparatus 1, thereby forming an electrostatic latent image. The image information from the original document read by the image reading device 2 or image information input to the image forming apparatus 1 by any mechanism during the formation of the latent image is transmitted to the exposure apparatus 13.

[0077] The exposure device 13 is composed of an LED printhead, which uses LEDs (Light Emitting Diodes) arranged along the axial direction of the photosensitive drum 11 as a plurality of light-emitting elements to irradiate light corresponding to image information onto the photosensitive drum 11 to form an electrostatic latent image.

[0078] The developing apparatus 14 is configured such that a developing roller 141, a stirring supply component 142, a stirring conveying component 143, and a layer thickness limiting component 144 are arranged inside a frame 140. The frame 140 has an opening opposite the photosensitive drum 11 and a developer-containing chamber. The developing roller 141 holds the developer 4 and conveys it to the developing area opposite the photosensitive drum 11. The stirring supply component 142 is composed of a screw conveyor or the like, which supplies the developer 4 through the developing roller 141 while stirring it. The stirring conveying component 143 is composed of a screw conveyor or the like, which conveys the developer 4 to the stirring supply component 142 while stirring it. The layer thickness limiting component 144 limits the amount (layer thickness) of the developer 4 held on the developing roller 141. In this developing apparatus 14, a power supply device (not shown) supplies a developing voltage between the developing roller 141 and the photosensitive drum 11. As a developer for four colors, for example, a two-component developer containing a non-magnetic toner and a magnetic carrier can be used.

[0079] The primary transfer device 15 is a contact-type transfer device equipped with a primary transfer roller, which contacts and rotates around the photosensitive drum 11 via the intermediate transfer belt 21, and is supplied with a primary transfer voltage. As the primary transfer voltage, a DC voltage with a polarity opposite to the charging polarity of the toner is supplied by a power supply device not shown.

[0080] like Figure 2As shown, the drum cleaning device 16 comprises a main body 160, a cleaning plate 161, and a delivery component 162. The main body 160 is formed as a container with a partial opening. The cleaning plate 161 is configured to contact the peripheral surface of the photosensitive drum 11 after one transfer with the required pressure to remove and clean residual toner and other adhering substances. The delivery component 162 comprises a spiral conveyor, etc., which conveys the toner and other adhering substances removed by the cleaning plate 161 in a manner that recovers them and delivers them to a recovery system (not shown).

[0081] like Figure 1 As shown, the intermediate transfer device 20 is positioned above each image generating device 10 (Y, M, C, K) along the vertical direction Z. This intermediate transfer device 20 mainly consists of an intermediate transfer belt 21, a plurality of belt support rollers 22-25, a secondary transfer device 30, and a belt cleaning device 26. Figure 2 As shown, the intermediate transfer belt 21 rotates in the direction indicated by arrow B while passing through the primary transfer position located between the photosensitive drum 11 and the primary transfer device 15. A plurality of belt support rollers 22-25 hold the intermediate transfer belt 21 from its inner surface in a desired state and support it rotatably. The secondary transfer device 30 is disposed on the outer peripheral surface (image holding surface) of the intermediate transfer belt 21 supported by the belt support rollers 25 to transfer the toner image on the intermediate transfer belt 21 to the recording paper 5. The belt cleaning device 26 removes and cleans any toner, paper dust, or other residues remaining on the outer peripheral surface of the intermediate transfer belt 21 after passing through the secondary transfer device 30.

[0082] The support roller 22 is configured as a drive roller that is rotated and driven by a drive device (not shown). The support roller 23 is configured as a surface-smoothing roller that maintains the moving position of the intermediate transfer belt 21. The support roller 24 is configured as a counter roller that faces a sensor (not shown). The support roller 25 is configured as a support roller for secondary transfer.

[0083] The secondary transfer device 30 is a contact-type transfer device equipped with a secondary transfer roller 31. The secondary transfer roller 31 contacts and rotates at the secondary transfer position on the outer peripheral surface of the intermediate transfer belt 21, which is supported by the support roller 25 in the intermediate transfer device 20, and is supplied with a secondary transfer voltage. Furthermore, a DC voltage exhibiting a polarity opposite to or the same as the charging polarity of the toner is supplied to the secondary transfer roller 31 or the support roller 25 of the intermediate transfer device 20 as the secondary transfer voltage.

[0084] like Figure 2As shown, the cleaning device 26 comprises a main body 260, a cleaning plate 261, and a delivery component 262. The main body 260 is formed as a partially open container. The cleaning plate 261 is configured to contact the circumferential surface of the intermediate transfer belt 21 after the secondary transfer with the required pressure to remove and clean residual toner and other adhering substances. The delivery component 262 comprises a screw conveyor or the like, which conveys the toner and other adhering substances removed by the cleaning plate 261 in a manner that recovers them and delivers them to a recovery system (not shown).

[0085] The fixing device 40 is configured to include a heating rotating body 41 and a pressure rotating body 42. The heating rotating body 41 is formed into a roller or belt type that is heated by a heating mechanism to maintain the surface temperature at a desired temperature. The pressure rotating body 42 is formed into a roller or belt type that contacts and rotates with a predetermined pressure approximately along the axial direction of the heating rotating body 41. An exit roller 43 for conveying the recording paper 5 that has undergone fixing treatment is provided at the exit of the fixing device 40. In this fixing device 40, the contact portion where the heating rotating body 41 contacts the pressure rotating body 42 becomes the fixing treatment portion for performing the required fixing treatment.

[0086] The sheet receiving device 50 is positioned below the image generating devices 10 (Y, M, C, K) in the vertical direction Z along the yellow (Y), magenta (M), cyan (C), and black (K) axes. This sheet receiving device 50, as an example of a sheet receiving body, mainly consists of a plurality of (or a single) paper trays 51, a push roller 52, a feed roller 53a, and a stop roller 53b. The paper trays 51 hold recording paper 5 of the desired size and type. The push roller 52 feeds the recording paper 5 from the paper trays 51. The feed roller 53a and stop roller 53b separate and supply the recording paper 5 fed by the push roller 52 one sheet at a time. The paper trays 51 are, for example, mounted so that they can be pulled out toward the front side (the side facing the user during operation), or, in the example, the front side of the paper surface. The sheet receiving device 50 will be described in detail later.

[0087] A paper feed path 56 is provided between the sheet receiving device 50 and the secondary transfer device 30. The paper feed path 56 is composed of a plurality of (or a single) paper transport roller pairs 54, 55 or transport guides (not shown) that transport the recording paper 5 from the sheet receiving device 50 to the secondary transfer position. The paper transport roller pairs 55 are configured, for example, as registration rollers to adjust the transport timing of the recording paper 5. Furthermore, a paper discharge conveyor 58 is provided at the upper part of the fixing device 40 along the vertical direction Z for discharging the fixed recording paper 5 from the exit roller 43 of the fixing device 40 to the sheet discharge device 60. The sheet discharge device 60 is disposed at the upper part of the device body 1a. The paper discharge conveyor 58 includes a first paper discharge conveyor path 57a to a fourth paper discharge conveyor path 57d.

[0088] The sheet discharge device 60 includes a first discharge tray 61, a second discharge tray 62, and a third discharge tray 63. The first discharge tray 61 and the second discharge tray 62 are cylindrical discharge trays located on the upper part of the device body 1a. The third discharge tray 63 is disposed on the side (left side in the figure) of the paper discharge conveyor section 58 facing outwards. Inside the paper discharge conveyor section 58 are a first paper discharge conveyor path 57a, a third paper discharge conveyor path 57c, and a fourth paper discharge conveyor path 57d. The first paper discharge conveyor path 57a includes a first paper discharge roller pair 64 for branching from the second paper discharge conveyor path 57b to discharge the recording paper 5 to the first discharge tray 61. The third paper discharge conveyor path 57c includes a second paper discharge roller pair 66 for branching from the second paper discharge conveyor path 57b to discharge the recording paper 5 to the second discharge tray 62. The fourth paper discharge conveyor path 57d has a third paper discharge roller pair 67 for branching off from the third paper discharge conveyor path 57c to discharge the recording paper 5 to the third discharge tray 63.

[0089] In addition, Figure 1 In the diagram, symbol 68 represents a pair of paper conveying rollers located midway along the second paper discharge conveying path 57b. Symbol G1 represents the first switching gate branching off the first paper discharge conveying path 57a from the second paper discharge conveying path 57b. Symbol G2 represents the second switching gate branching off the third paper discharge conveying path 57c from the fourth paper discharge conveying path 57d.

[0090] And, as Figure 1As shown, a double-sided conveying path 70 is provided inside the main body 1a of the device. During the period when the recording paper 5, on which an image is formed on one side, is held by the first paper discharge roller pair 64, the double-sided conveying path 70 switches the rotation direction of the first paper discharge roller pair 64 from the forward direction to the reverse direction. The double-sided conveying path 70 includes a paper transport roller pair 69 that re-conveys the recording paper 5 with its reversed sides to the paper transport roller pair 55.

[0091] exist Figure 1 In the diagram, symbols 145 (Y, M, C, K) represent toner cartridges containing at least a toner-containing developer supplied to the corresponding developing apparatus 14. A plurality of toner cartridges 145 (Y, M, C, K) are arranged in a direction perpendicular to the paper surface.

[0092] Furthermore, in Figure 1 In the diagram, symbol 200 indicates a control device that centrally controls the operation of the image forming apparatus 1. The control device 200 includes a CPU (Central Processing Unit) or ROM (Read Only Memory), RAM (Random Access Memory) (not shown), or a bus or communication interface connected to these CPUs or ROMs.

[0093] <Operation of the image forming apparatus>

[0094] The following describes the basic image forming operation based on the image forming apparatus 1.

[0095] Here, the operation of using the four image generation devices 10 (Y, M, C, K) to form a panchromatic image composed of the tonal images of the four colors (Y, M, C, K) will be described.

[0096] If the control device 200 receives an instruction to request an image forming action (printing), the image forming device 1 activates four image generating devices 10 (Y, M, C, K), an intermediate transfer device 20, a secondary transfer device 30, a fixing device 40, etc.

[0097] Then, in each image generating apparatus 10 (Y, M, C, K), firstly, each photosensitive drum 11 is rotated in the direction indicated by arrow A, and each charging device 12 charges the surface of each photosensitive drum 11 to the desired polarity and potential. Next, the exposure device 13 illuminates the surface of the charged photosensitive drum 11 with light, which is emitted based on the image signal obtained by converting the image information input to the image forming apparatus 1 into each color component (Y, M, C, K). Then, an electrostatic latent image of each color component, consisting of the desired potential difference, is formed on the surface of the charged photosensitive drum 11.

[0098] Next, each developing unit 14 supplies toner of the corresponding color (Y, M, C, K) charged to the desired polarity to the electrostatic latent image of each color component formed on the photosensitive drum 11 from the developing roller 141, so that it can be electrostatically attached for development. Through this development, the electrostatic latent image of each color component formed on each photosensitive drum 11 is developed as a toner image of the four colors (Y, M, C, K) developed by the toner of its corresponding color.

[0099] Next, the toner images of each color formed on the photosensitive drums 11 of each image generation device 10 (Y, M, C, K) are transferred to the primary transfer position. Then, the primary transfer device 15 performs a primary transfer while the toner images of each color are sequentially superimposed on the intermediate transfer belt 21 which rotates in the direction indicated by arrow B of the intermediate transfer device 20.

[0100] Furthermore, in each image generating device 10 (Y, M, C, K) after one transfer operation, the drum cleaning device 16 scrapes away the adhering material to clean the surface of the photosensitive drum 11. As a result, each image generating device 10 (Y, M, C, K) is ready to perform the next image generating operation.

[0101] Next, in the intermediate transfer device 20, the toner image transferred once by the rotation of the intermediate transfer belt 21 is held and conveyed to the secondary transfer position. On the other hand, in the sheet receiving device 50, the required recording paper 5 is fed to the paper feed path 56 in conjunction with the image generation operation. On the paper feed path 56, the paper conveying roller pair 55, which serves as the registration roller, feeds the recording paper 5 and supplies it to the secondary transfer position in conjunction with the transfer period.

[0102] At the secondary transfer position, the secondary transfer roller 31 of the secondary transfer device 30 transfers the toner image on the intermediate transfer belt 21 onto the recording paper 5. Furthermore, in the intermediate transfer device 20 after the secondary transfer is completed, the belt cleaning device 26 removes and cleans any remaining toner or other residues on the surface of the intermediate transfer belt 21 after the secondary transfer.

[0103] Next, the recording paper 5, with the toner image transferred twice, is peeled off from the intermediate transfer belt 21 and the secondary transfer roller 31 and conveyed to the fixing device 40. In the fixing device 40, the recording paper 5 after the secondary transfer is guided through the contact portion between the rotating heating rotor 41 and the pressure rotor 42. This performs the required fixing process to fix the unfixed toner image onto the recording paper 5. Finally, after fixing, the recording paper 5, during the image forming operation (image forming only on one side), is discharged via the first paper discharge conveyor path 57a to the fourth paper discharge conveyor path 57d onto any one of the first discharge trays 61 to the third discharge tray 63 located on the upper part of the device body 1a.

[0104] Furthermore, when images are formed on both sides of the recording paper 5, the first paper ejection roller pair 64 conveys the recording paper 5 with an image formed on one side to the ejection direction of the first ejection tray 61. Then, while the first paper ejection roller pair 64 holds the rear end of the recording paper 5, the rotation direction of the first paper ejection roller pair 64 is switched to the reverse direction. The recording paper 5 conveyed in the opposite direction by the first paper ejection roller pair 64 is conveyed to the double-sided conveying path 70 equipped with the paper conveying roller pair 69, etc., and is conveyed again to the paper conveying roller pair 55 in a reversed state. The paper conveying roller pair 55 delivers the recording paper 5 in conjunction with the transfer period and supplies it to the secondary transfer position. An image is formed on the reverse side of the recording paper 5 and fixed. The recording paper 5 with the image fixed on the reverse side is ejected via any one of the first paper ejection conveying paths 57a to 4th paper ejection conveying paths 57d to any one of the first ejection trays 61 to 3rd ejection trays 63 provided on the upper part of the device body 1a.

[0105] Through the above actions, a recording paper 5 is output, which has a full-color image composed of a combination of four color tones formed on one or both sides.

[0106] <Structure of the Sheet Receiving Device>

[0107] like Figure 1As shown, the image forming apparatus 1 includes a sheet receiving device 50. The sheet receiving device 50 is configured to exist inside the apparatus body 1a and below the yellow (Y), magenta (M), cyan (C), and black (K) image generating devices 10 (Y, M, C, K) along the vertical direction Z. The apparatus body 1a of the image forming apparatus 1 also serves as the apparatus body of the sheet receiving device 50. This sheet receiving device 50 mainly consists of a plurality of (four in the example shown) paper trays 51, push rollers 52, feed rollers 53a, and stop rollers 53b. The paper trays 51 receive recording paper 5 of the desired size and type. The push rollers 52, feed rollers 53a, and stop rollers 53b feed the recording paper 5 one sheet at a time from each paper tray 51.

[0108] As described above, the paper tray 51 is, for example, installed so that it can be pulled out toward the front side (the side that the user faces during operation) of the device body 1a, which in the example is the front side of the paper surface.

[0109] like Figure 3 As shown, the paper tray 51 is configured as a generally rectangular box with a height corresponding to the number of sheets of recording paper 5 contained inside, and a fully open upper surface. The paper tray 51 includes a bottom wall portion 511, left and right side walls portions 512 and 513, and front and rear walls portions 514 and 515. The bottom wall portion 511 is formed into a generally rectangular shape in plan. The left and right side walls portions 512 and 513 are arranged to the left and right along the horizontal direction X of the bottom wall portion 511. Furthermore, the front and rear walls portions 514 and 515 are arranged to the front and rear along the rear side direction Y of the bottom wall portion 511. The front of the paper tray 51 is formed into an operation panel 516. The operation panel 516, together with the front panel (not shown) of the device body 1a, constitutes the appearance shape of the front of the device body 1a. The operation panel 516 of the paper tray 51 is provided with a handle portion 517 for the user to hold when pulling the paper tray 51 out of the device body 1a or pushing (pulling) it into the device body 1a.

[0110] A detection mechanism (not shown) is provided in the main body 1a of the device. This detection mechanism detects the pulling out of the paper feed tray 51 when the user holds the handle 517 of the operation panel 516 and pulls it out from the main body 1a. In addition, this detection mechanism can also serve as a size detection mechanism 520b for detecting the size of the recording paper 5, which will be described later.

[0111] A base plate 518 for stacking multiple sheets of recording paper 5 is disposed on the bottom wall 511 of the paper supply tray 51. The base plate 518 is rotatably mounted on the front and rear walls 514 and 515 of the paper supply tray 51 with a pivot point 518a as its center. The pivot point 518a is provided at the front and rear ends of the base plate 518 along the rear side direction Y. As a result, the downstream end 518c of the base plate 518 along the paper supply direction can rotate upward. A drive member 519 is rotatably disposed on the back side of the downstream end 518c of the base plate 518 along the paper supply direction. Figure 3 Part of the drive component 519 is shown in dashed lines; its middle portion 519a is formed in a crank shape. The front end of the drive component 519 is rotatably mounted to the bottom wall portion 511 of the paper feed tray 51 via a pivot support portion 519b. A connecting portion 519c, which receives the driving force from the device body 1a, is provided on the rear wall portion 515 of the paper feed tray 51. Figure 5 As shown, when the paper supply tray 51 is installed in the paper supply position of the device body 1a, the drive component 519 transmits driving force from the drive mechanism 520a provided in the device body 1a via the connecting component 519c and rotates in the desired direction to drive the required angle.

[0112] Furthermore, if the paper supply tray 51 is pulled out from the main body 1a, the base plate 518 separates from the drive mechanism 520a on the side of the main body 1a and descends to the bottom wall 511 by its own weight. Additionally, Figure 3 This indicates that the base plate 518 has descended to the bottom wall section 511.

[0113] On the other hand, when the detection mechanism (not shown) detects that the paper feed tray 51 is installed in the paper feed position of the device body 1a, the base plate 518 is moved upward by the drive member 519 via the drive mechanism 520a on the device body 1a side and the connecting member 519c. Then, the base plate 518 stops at the paper feed position where the uppermost recording paper 5 in the paper feed tray 51 abuts against the push roller 52.

[0114] like Figure 3As shown, an end guide plate 521 and side guide plates 522 and 523 are disposed on the bottom wall portion 511 of the paper supply tray 51. The end guide plate 521 abuts against and is positioned at the upstream end of the recording paper 5 housed inside the paper supply tray 51 along the paper supply direction. The side guide plates 522 and 523 abut against and are positioned at their respective ends along the width direction intersecting the paper supply direction. The end guide plate 521 is mounted on the bottom wall portion 511 of the paper supply tray 51 in a manner that allows it to move along the paper supply direction of the recording paper 5 and remain in a stopped position. Furthermore, the side guide plates 522 and 523 are mounted on the bottom wall portion 511 of the paper supply tray 51 in a manner that allows them to move only an equal distance along the width direction intersecting the paper supply direction with reference to the center of the width direction intersecting the paper supply direction and remain in a stopped position. The paper supply tray 51 supplies the recording paper 5 with reference to the center portion along the back side direction Y intersecting the paper supply direction (so-called center alignment). A size recognition mechanism (not shown) is arranged on the rear wall 515 of the paper supply tray 51, facing rearward. This size recognition mechanism identifies the size of the recording paper 5 based on the positions of the end guide plate 521 and the side guide plates 522 and 523. Figure 5 As shown, the size recognition mechanism is detected by the size detection mechanism 520b, which is composed of a plurality of switches on the side of the device body 1a.

[0115] The base plate 518 is provided with a plurality of planar rectangular openings 524 that allow the movement of the end guide plate 521 and the side guide plates 522 and 523.

[0116] In the sheet receiving device 50, such as Figure 4 As shown, the push roller 52 is rotatably positioned at a position corresponding to the downstream end of each paper tray 51 along the paper feeding direction, in a manner that allows for desired timing. The push roller 52 abuts against and supplies the surface of the uppermost recording paper 5 mounted on the base plate 518.

[0117] Furthermore, in the sheet receiving device 50, the feed roller 53a and the deflector roller 53b are arranged downstream of the push roller 52 along the paper feeding direction. The feed roller 53a and the deflector roller 53b are driven to rotate at a desired timing. The feed roller 53a and the deflector roller 53b press against each other, conveying only the uppermost sheet of recording paper 5 supplied by the push roller 52 downstream along the paper feeding direction. On the other hand, the deflector roller 53b is forced to rotate in the opposite direction to the feed roller 53a. The deflector roller 53b conveys the second and subsequent sheets of recording paper 5 supplied together with the uppermost sheet of recording paper 5 in the opposite direction to the paper feeding direction. Then, the deflector roller 53b plays a role in preventing the separation of multiple sheets of recording paper 5 supplied at the same time.

[0118] The push roller 52, feed roller 53a and deflector roller 53b are positioned relative to each paper tray 51 on the rear side along the width direction intersecting the paper feeding direction of the recording paper 5.

[0119] like Figure 4 As shown, an inlet plate 525 is provided on the left side wall 512 at the downstream end of the paper feed tray 51 along the paper feed direction. The inlet plate 525 guides the front end of the recording paper 5, which is supplied by the push roller 52 to the front side along the width direction intersecting the paper feed direction of the recording paper 5, into the engagement part of the feed roller 53a and the blocking roller 53b.

[0120] The main body 1a of the device is provided with a guide member 526, which serves as a guide member. The guide member 526 guides the recording paper 5 supplied from the paper tray 51 by the push roller 52, the feed roller 53a and the deflection roller 53b upward along the vertical direction Z.

[0121] like Figure 6 As shown, the sheet receiving device 50 is mounted on a plurality of support frames 71, 72, etc., constituting the device body 1a of the image forming apparatus 1. Horizontal frames 73, front plates 74, partition plates 75, and zoning plates 76 are provided on the support frames 71, 72 by means of fastening with bolts (not shown). The horizontal frames 73 are respectively arranged on the left and right sides of the device body 1a along the horizontal direction X. On the left and right horizontal frames 73, the left and right sidewalls 512, 513 of the paper supply trays 51 are pulled out and pushed in via guide rails and guide rollers (not shown). Yellow (Y), magenta (M), blue-green (C), and black (K) image generating devices 10 (Y, M, C, K) are mounted on the front plate 74. The partition plates 75 separate the image generating devices 10 (Y, M, C, K) from the sheet receiving device 50. The zoning plates 76 zonify the plurality of paper supply trays 51 of the sheet receiving device 50. The sheet receiving device 50 includes a push roller 52, a feed roller 53a, and a stop roller 53b, which are mounted on the horizontal frame 73 on the left.

[0122] like Figure 1 As shown, the recording paper 5, supplied from the sheet receiving device 50 and guided by the guide member 526 to the upper part along the vertical direction Z, is conveyed to the secondary transfer position via a paper feed conveying path 56 consisting of a plurality of (or a single) paper conveying roller pairs 54, 55 or conveying guides not shown.

[0123] <Structure of the sheet receiving device's pull-in mechanism>

[0124] The sheet receiving device includes: a joining mechanism disposed in either the device body or the sheet receiving body; and a pulling mechanism disposed in the other of the device body or the sheet receiving body, and having a guide groove that engages with the joining mechanism to guide the pulling action of pulling the sheet receiving body into the interior of the device body.

[0125] In the sheet receiving device 50 according to Embodiment 1, such as Figure 6 As shown, an engagement pin 77, as an example of an engagement mechanism, is provided on the main body 1a of the device. The engagement pin 77 is formed into a cylindrical shape from a metal such as stainless steel. The engagement pin 77 is mounted on the front end of the swing arm 78 in an upright position facing upwards along the vertical direction Z. Figure 7 As shown, the swing arm 78 is oscillatingly disposed at the front end of the horizontal frame 73 located on the left side of the device body 1a along the horizontal direction X, with fulcrum 78a as the center. In the swing arm 78, a limiting plate 78b disposed at the end opposite to the engaging pin 77 relative to the fulcrum 78a limits the swing angle by engaging with a fan-shaped slot 79 that opens in the horizontal frame 73.

[0126] like Figure 6 As shown, the sheet receiving device 50 has a pull-in device 80 on the paper supply tray 51 side, which serves as an example of a pull-in mechanism. The pull-in device 80 performs a pull-in action by engaging with a connecting pin 77 on the device body 1a side to pull the paper supply tray 51 into the device body 1a. Figure 3 As shown, the pull-in device 80 is installed on the back side of the operation panel 516, which is fixed to the front end of the paper supply tray 51 in the rear direction Y and the downstream end in the paper supply direction. Alternatively, the engagement pin 77 can be disposed on the paper supply tray 51, and the pull-in device 80 can be disposed on the back side of the device body 1a, such as the end of the device body 1a. However, when the pull-in device 80 is disposed on the paper supply tray 51, compared to when it is disposed on the back side of the device body 1a, the installation space on the back side of the device body 1a can be omitted, thereby enabling miniaturization of the device body 1a.

[0127] like Figure 8 As shown, the pull-in device 80 is configured as a relatively low, flat box-shaped structure with one end (the upper end in the figure) protruding in a trapezoidal shape toward the rear side along the rearward direction Y. Figure 9 and Figure 10 As shown, the pull-in device 80 generally includes a receiving box 81, a bracket 82, a helical spring 83, a plurality of gears 94-98, and a low-torque damper 99, etc.

[0128] like Figure 8 As shown, the container 81 consists of a main body 810 and a cover 811 that closes the upper surface of the main body 810. Figure 9 As shown, the box body 810 has a bottom wall 812 and an outer peripheral wall 813 that covers the entire circumference of the bottom wall 812. The local height of the bottom wall 812 of the box body 810, that is, the position of the bottom wall 812 along the vertical direction Z, is different. The bottom wall 812 is set as follows: the area where the guide groove 91 described later is provided is relatively high, and the area where a plurality of gears 94 to 98 and a low torque damper 99 are provided is relatively low.

[0129] The outer peripheral wall 813 of the box body 810 has left and right side walls 814 and 815 located along the horizontal direction X, and front and rear side walls 816 and 817 located along the rear side direction Y. For example... Figure 9 As shown, the rear sidewall 817 of the box body 810 is composed of a first rear sidewall 817a, an inclined wall 817b, and a second rear sidewall 817c. The first rear sidewall 817a is located at the rearmost end along the rearward direction Y and is shorter along the horizontal direction X. The inclined wall 817b is inclined from the right end of the first rear sidewall 817a toward the front end along the rearward direction Y. The second rear sidewall 817c is located at the frontmost end along the rearward direction Y and is longer along the horizontal direction X. An inlet 90 for the engaging pin 77 on the side of the inlet device body 1a is provided on the first rear sidewall 817a of the box body 810. Figure 9 As shown, the inlet 90 is formed into a roughly V-shaped form with two side surfaces 90a and 90b that are inclined to the left and right at approximately 45 degrees relative to the rear side direction Y, which is the direction of pulling in. Furthermore, a cutout 816a is provided on the front side wall 816 of the box body 810 to allow the bracket 82 to rotate.

[0130] like Figure 8 As shown, the box body 810, with the bracket 82, coil spring 83, multiple gears 94-98, and low-torque damper 99 housed within it, has its upper surface closed by a snap-fit ​​cover 811. In the figure, reference numerals 818a and 818b denote snap-fit ​​joints. Furthermore, reference numeral 818c denotes a fixing piece that is positioned and fixed by engaging with a not shown groove provided on the inner surface of the cover 811. Additionally, as... Figure 10 As shown, the box body 810 is mounted via mounting holes 819 provided at the three corners of the bottom wall 812 (see reference). Figure 9 ) Secure it to the paper supply tray 51 with screws 86.

[0131] like Figure 9 and Figure 10As shown, a guide groove 91 is provided on the bottom wall 812 of the box body 810 in communication with the inlet 90 of the first rear side wall 817a. A raised wall 92 is formed around the entire outer periphery of the guide groove 91, causing the bottom wall 812 of the box body 810 to stand upright towards the inward. The inner circumferential surface 92a of this raised wall 92 functions as a guide surface for the guiding engagement pin 77.

[0132] Inside the box body 810, a bracket 82 is rotatably mounted, which rotates by engaging with a coupling pin 77. For example... Figure 11 As shown, the bracket 82 is constructed as a hollow frame with a roughly rectangular cross-section by bending a metal plate. The bracket 82 has an upper end portion 820 and a lower end portion 821 arranged approximately parallel to each other. The upper end portion 820 and the lower end portion 821 of the bracket 82 are connected to each other by a side wall portion 822 located at the end on the guide groove 91 side. The bracket 82 is configured as a hollow structure in which the upper end portion 820 and the lower end portion 821 are separated vertically from each other, except for the side wall portion 822. In addition, on the bracket 82, a limiting plate 823 is provided at the end opposite to the side wall portion 822, bent downward from the end of the upper end portion 820, to limit the position of the coil spring 83. Furthermore, on the lower end portion 821 of the bracket 82, a stop piece 824 is provided at the end opposite to the inlet 90 of the side wall portion 822, bent upward. The stop plate 824 stops the clockwise rotation of the bracket 82 by abutting against the inner side of the inclined wall 817b of the box body 810.

[0133] The bracket 82 is rotatably supported on the box body 810 and the cover 811 by rotating shafts 825 and 826. The rotating shafts 825 and 826 are configured to protrude in the vertical direction at the upper end 820 and the lower end 821 of the bracket 82, respectively.

[0134] A connecting member 84 is integrally provided on the lower end 821 of the bracket 82, on the end facing the inlet 90. The connecting member 84 has a connecting groove 841 that engages with the connecting pin 77. The connecting member 84 is formed of synthetic resin or the like. The connecting member 84 is fitted to the bracket 82 by clamping the front end of the lower end 821 of the bracket from both sides, or fixed to the bracket 82 by means of adhesive or the like. The connecting groove 841 has a straight portion 841a arranged in a straight line along one side 90a of the inlet 90, and a bent portion 841b that is bent shorter along the pull-in direction at the inner end of the straight portion 841a. The opening ends 842 and 843 of the connecting groove 841 are formed in a curved shape so that the connecting pin 77 can be inserted. Alternatively, the connecting groove 841 may be formed directly as a metal plate constituting the bracket 82.

[0135] like Figure 9As shown, one end 831 of a coil spring 83, which constitutes an example of a force-applying mechanism that applies a rotational torque to the bracket 82, is engaged with the bracket 82. Figure 11 As shown, one end 831 of the helical spring 83 is locked onto a locking portion 827a, which has a smaller outer diameter, provided on a locking pin 827 located near the side wall portion 822 of the bracket 82. Furthermore, as... Figure 10 As shown, the other end 832 of the helical spring 83 is locked onto the locking portion 85a of the locking pin 85 mounted below the right side wall 815 of the box body 810. The helical spring 83 is always in the extended state, so that the tensile force corresponding to the spring constant of the helical spring 83 acts on the bracket 82.

[0136] In bracket 82, such as Figure 9 As shown, before engaging with the engagement pin 77, the engagement groove 841 is in a stopped position, slightly rotated clockwise from its position opposite the inlet 90. At this time, the coil spring 83 is located slightly closer to the rear side of the paper feed tray 51, i.e., above, than the rotation axes 825 and 826 of the bracket 82. As a result, a clockwise torque is applied to the bracket 82 by the contraction force of the coil spring 83. In addition, the bracket 82 is stopped by abutting against the inner side of the box body 810 via the stop plate 824.

[0137] In bracket 82, such as Figure 6 As shown, the paper tray 51 is pushed into the interior of the device body 1a of the image forming apparatus 1, thereby causing the engaging pin 77 on the device body 1a side to move from the inlet 90 into the guide groove 91. Thus, in the bracket 82, as... Figure 9 As shown, the engaging pin 77 engages with the engaging groove 841, and rotates counterclockwise as the engaging pin 77 moves. Consequently, the coil spring 83 moves closer to the front of the paper feed tray 51 than the rotation axes 825 and 826 of the bracket 82. Figure 9 The movement moves downwards and to the center. As a result, a counterclockwise torque is applied to the bracket 82 by the contraction force of the helical spring 83.

[0138] Then, as the engaging pin 77 moves along the guide groove 91 inside the box body 810, the bracket 82 rotates counterclockwise under the rotational torque exerted by the contraction force of the coil spring 83.

[0139] like Figure 9 and Figure 10As shown, a plurality of gears 94 to 98 are arranged inside the box body 810 to transmit the rotation of the bracket 82 to the low-torque damper 99. A first gear 94 is fixed on the bracket 82. The first gear 94 rotates together with the bracket 82. The bracket 82 rotates within the box body 810 by the required angle (approximately 180 degrees). On the first gear 94, teeth 941 constituting the first gear 94 are provided only in the area where the bracket 82 rotates. Specifically, teeth 941 are formed on the first gear 94 within the range of the bracket 82's rotatable angle, i.e., approximately 180 degrees.

[0140] like Figure 10 As shown, the first gear 94 has an insertion port 942 at its center opening, into which the rotating shaft 826 of the bracket 82 is inserted in a non-rotating state. Furthermore, on the first gear 94, at a position opposite to the area where the teeth 941 are located, there is a roughly triangular-shaped abutment portion 943 extending radially outward. When the first gear 94 and the bracket 82 rotate clockwise together, the abutment portion 943 abuts against the inner surface of the inclined wall 817b of the box body 810, and together with the stop plate 824, stops the rotation of the bracket 82.

[0141] The first gear 94 meshes with the second gear 95, which constitutes a plurality of speed-increasing gear sets. The number of teeth n2 of the second gear 95 is less than the number of teeth n1 converted to a full revolution of the first gear 94. The outer diameter R1 of the first gear 94 is greater than the outer diameter R2 of the second gear 95. Furthermore, the symbols R1, R2, etc., indicating the outer diameters of the first gear 94 or the second gear 95 are omitted from the illustration. Therefore, the rotation of the first gear 94 is increased according to the ratio of the number of teeth and transmitted to the second gear 95. Below the second gear 95, a third gear 96 is arranged coaxially and rotatably with respect to the rotation axis 99b. The outer diameter R3 of the third gear 96 is greater than the outer diameter R2 of the second gear 95. The number of teeth n3 of the third gear 96 is greater than the number of teeth n2 of the second gear 95. The second gear 95 and the third gear 96 constitute a mechanical one-way clutch 100. Figure 12 As shown, a plurality of protrusions 95b, each with a right-angled triangular cross-section, are evenly spaced circumferentially around the rotation axis 99b on the lower surface 95a of the second gear 95. Conversely, a plurality of protrusions 96b, each with a right-angled triangular cross-section, are evenly spaced circumferentially around the rotation axis 99b on the upper surface 96a of the third gear 96, each with a right-angled triangular cross-section, which mesh with the protrusions 95b of the second gear 95. The second gear 95 is in pressure contact with the third gear 96 via a coil spring 101. The coil spring 101 is pressed against the inner surface of the cover 811 by mounting the cover 811 to the box body 810.

[0142] In the mechanical one-way clutch 100, when the second gear 95 rotates clockwise, the protrusion 95b of the second gear 95 meshes with the protrusion 96b of the third gear 96, transmitting rotational force to the third gear 96. Conversely, when the second gear 95 rotates counterclockwise, the inclined surface of the protrusion 95b of the second gear 95 slides onto the inclined surface of the protrusion 96b of the third gear 96, and the rotational force of the second gear 95 is not transmitted to the third gear 96. Therefore, when the paper feed tray 51 is pulled out from the device body 1a, if the bracket 82 rotates clockwise, the second gear 95 rotates counterclockwise, and the rotation of the bracket 82 is not transmitted to the third gear 96 via the mechanical one-way clutch 100.

[0143] Furthermore, the third gear 96 meshes with the fourth gear 97. The outer diameter R4 of the fourth gear 97 is smaller than the outer diameter R3 of the third gear 96. The number of teeth n4 of the fourth gear 97 is less than the number of teeth n3 of the third gear 96. A fifth gear 98 is coaxially and integrally mounted on the fourth gear 97. The outer diameter R5 of the fifth gear 98 is larger than the outer diameter R4 of the fourth gear 97. The number of teeth n5 of the fifth gear 98 is more than the number of teeth n4 of the fourth gear 97.

[0144] The fifth gear 98 meshes with the sixth gear 99a disposed in the low torque damper 99. The outer diameter R6 of the sixth gear 99a is smaller than the outer diameter R5 of the fifth gear 98. The number of teeth n6 of the sixth gear 99a is less than the number of teeth n5 of the fifth gear 98. The low torque damper 99 is fixed to the bottom wall 812 of the housing body 810, which is formed one level lower. In the low torque damper 99, if a rotational force (torque) is applied to its sixth gear 99a, the torque is limited to a relatively low and approximately constant torque. The torque damper is, for example, a buffer device that uses the viscous resistance of oil to limit the torque acting on the rotating shaft of the sixth gear 99a to a constant value. The low torque damper 99 is configured such that the value of the torque that can be limited is relatively low. Compared with the high torque damper, the low torque damper 99 is smaller and less expensive.

[0145] In this embodiment 1, the rotation of the bracket 82 is transmitted to the low-torque damper 99 via a multi-stage (3-stage) speed-increasing gear train consisting of a plurality of gears 94 to 98. Conversely, the limiting torque of the low-torque damper 99 is amplified and transmitted to the bracket 82 via the plurality of gears 94 to 98. Therefore, in the pull-in device 80 according to this embodiment 1, even when a small and inexpensive low-torque damper 99 is used, a sufficiently large limiting torque can be applied to the bracket 82.

[0146] However, in the existing sheet receiving device 50, such as Figure 13 As shown, the guide groove 91 of the pull-in device 80 is shaped as an arc with a roughly defined radius of curvature.

[0147] Therefore, in the existing sheet receiving device 50, if the user forcefully pushes the paper supply tray 51 into the device body 1a, the rotational torque acting on the bracket 82 via the engaging pin 77 of the device body 1a becomes excessive. Consequently, the low-torque damper 99, which limits the rotation of the bracket 82 to a roughly constant torque, may not function effectively. Thus, the following technical problem arises: the pulling speed of the paper supply tray 51 unexpectedly increases, making it impossible to sufficiently decelerate the paper supply tray 51.

[0148] On the other hand, in the existing sheet receiving device 50, the guide groove 91 is shaped as an arc with a roughly predetermined radius of curvature. Therefore, the pulling force acting on the paper supply tray 51 is roughly constant. As a result, when the paper supply tray 51 is pushed into the interior of the device body 1a, the pulling force acting on the paper supply tray 51 is insufficient, which may result in poor pulling of the paper supply tray 51.

[0149] In particular, in existing sheet receiving devices 50, in order to achieve cost reduction, a low-torque damper 99 is sometimes used as a component constituting the pull-in device 80, or parts such as the one-way clutch 100 are omitted and replaced with mechanical parts. Therefore, in existing sheet receiving devices 50, the following technical problems arise due to deviations in the internal reaction force generated when the paper supply tray 51 is installed on the device body 1a. Specifically, in existing sheet receiving devices 50, due to insufficient limiting torque based on the low-torque damper 99 or operational delays caused by the omission of the one-way clutch 100, there may be areas where the pull-in speed of the paper supply tray 51 is too fast or where the pull-in force is insufficient.

[0150] Therefore, the sheet receiving device according to Embodiment 1 is configured such that a resistance action part is provided in the guide groove of the pulling mechanism to cause resistance to the pulling action of the sheet receiving body, so as to adjust the pulling force of the sheet receiving body.

[0151] Furthermore, in the sheet receiving device according to Embodiment 1, the resistance part is disposed at the beginning end of the pull-in action of the guide groove on the sheet receiving body.

[0152] Furthermore, in the sheet receiving device according to Embodiment 1, the resistance section is composed of a region that bends and / or flexes the guide groove in the pulling direction of the sheet receiving body. Also, the resistance section is composed of a region that bends multiple times in the pulling direction of the sheet receiving body.

[0153] That is, such as Figure 10 and Figure 14As shown, the sheet receiving device 50 according to Embodiment 1 has a resistance part 910 in the guide groove 91 provided in the receiving box 81 of the pull-in device 80, which is composed of a region that bends and / or flexes the guide groove 91 in the pull-in direction of the paper supply tray 51.

[0154] like Figure 14 As shown, the resistance unit 910 is disposed at the end of the guide groove 91 at the beginning of the pull-in action, i.e., at the inlet 90 side. The resistance unit 910 is composed of a bending portion 911 that bends the guide groove 91 at the end located at the inlet 90 side by approximately 90 degrees, and a bending portion 912 that bends the guide groove 91 at the front end of the bending portion 911 to an angle greater than 90 degrees. The bending directions of the bending portion 911 and the bending portion 912 are set to be opposite to each other. The beginning of the pull-in action of the guide groove 91 is arranged in a straight line along one side 90a of the inlet 90. Then, the bending portion 911 of the resistance unit 910 is formed by a short bend of approximately 90 degrees from a short straight section continuous with the beginning of the pull-in action of the guide groove 91.

[0155] The outer peripheral surface 911a of the bent portion 911 of the resistance action portion 910 is formed in an arc shape. Therefore, the connecting pin 77 with a circular cross-section makes smooth contact with the outer peripheral surface 911a of the bent portion 911. Furthermore, both the inner and outer peripheral surfaces 912a and 912b of the bent portion 912 of the resistance action portion 910 are formed in a curved shape.

[0156] In the guide groove 91, the intermediate portion 913, which is continuous with the resistance part 910, is formed into an arc shape of a long strip with a predetermined radius of curvature. The intermediate portion 913 has a center O of the arc at a desired distance along a direction intersecting the pull-in direction. When the engaging pin 77 moves in the intermediate portion 913 of the guide groove 91, it is subjected to a pull-in force along the pull-in direction by means of the helical spring 83.

[0157] Furthermore, in the sheet receiving device 50 according to Embodiment 1, the guide groove 91 includes a facilitating part 914 that promotes the pulling-in action of the paper supply tray 51. The facilitating part 914 is disposed at the end end of the pulling-in action of the guide groove 91 on the paper supply tray 51. The facilitating part 914 is formed as a straight line that is slightly inclined from the end end of the middle part 913 relative to the back side direction Y, which is the pulling direction. Therefore, the engaging pin 77, which moves along the facilitating part 914, moves in a direction away from the rotation axes 825, 826 of the bracket 82, that is, the pulling force exerted by the bracket 82 increases, thereby promoting the pulling-in action.

[0158] <Function of Sheet Receiving Device>

[0159] In the sheet receiving device according to Embodiment 1, as described below, compared with the case where there is no resistance part in the guide groove of the pulling mechanism, the pulling force of the sheet receiving body can be adjusted.

[0160] That is, in the sheet receiving device 50 according to Embodiment 1, such as Figure 6 As shown, when replenishing the paper supply tray 51 with recording paper 5, the user pulls the paper supply tray 51 out to the front side of the device body 1a. Then, the recording paper 5 is replenished into the paper supply tray 51. Then, the paper supply tray 51 is installed in the paper supply position inside the device body 1a by the user pushing it into the device body 1a through the handle 517 of the operation panel 516.

[0161] At this time, if the paper supply tray 51 is pushed into the device body 1a to a certain extent, the engaging pin 77 of the device body 1a is guided into the interior from the inlet 90 of the pull-in device 80 provided on the paper supply tray 51. At this time, if Figure 7 As shown, the engagement pin 77 is located at any position within the movable range of the swing arm 78. Figure 14 As shown, the inlet 90 of the pull-in device 80 opens in a generally V-shaped planar shape. Therefore, the engaging pin 77 is inserted into the interior of the inlet 90 along the two sides 90a, 90b of the generally V-shaped planar opening of the inlet 90 of the pull-in device 80.

[0162] The paper tray 51 is guided into the interior of the pull-in device 80 via the connecting pin 77 of the main body 1a, and is connected to the main body 1a via the connecting pin 77 and the pull-in device 80. Figure 15 As shown, if the engaging pin 77 is inserted from the inlet 90 into the interior of the pull-in device 80, it moves into the guide groove 91, which is continuously provided with the inlet 90. A resistance part 910 is provided at the beginning of the pull-in action of the guide groove 91, i.e., at the entrance of the guide groove 91. Therefore, if the engaging pin 77 moves from the inlet 90 into the guide groove 91, it is resisted by the resistance part 910 provided at the beginning of the pull-in action of the guide groove 91.

[0163] like Figure 15As shown, the resistance section 910 of the guide groove 91 includes a bent section 911 that bends approximately 90 degrees in the direction of introduction from the inlet 90, and a bent section 912 that bends at an angle greater than 90 degrees to the bending direction of the bent section 911. Therefore, the traveling direction of the engaging pin 77 changes approximately 90 degrees when it comes into contact with the outer peripheral surface 911a of the bent section 911 constituting the guide groove 91. At this time, it is assumed that a pulling force F1 acts on the engaging pin 77 in the pulling direction. Thus, the engaging pin 77 receives a resistance -F2, which is approximately equal to and in the opposite direction to the contact force F2, which is a component of the pulling force F1 on the outer peripheral surface 911a, by contacting the bent section 911. Simultaneously, a pushing force F3, which reduces the pulling force F1 in a direction parallel to the outer peripheral surface 911a of the bent section 911, acts on the engaging pin 77.

[0164] Similarly, when the engaging pin 77 passes through the bend 912 of the resistance part 910, it is resisted from the inner and outer peripheral surfaces 912a and 912b of the bend 912, and the initial pulling force F1 is greatly reduced.

[0165] Furthermore, in the pull-in device 80 according to Embodiment 1, such as Figure 16 As shown, when the engaging pin 77 moves in the resistance part 910 of the guide groove 91, the bracket 82, which engages with the engaging pin 77, rotates counterclockwise. The rotation of the bracket 82 is then transmitted to the low-torque damper 99 via the first gear 94 to the fifth gear 98. Therefore, the limiting torque based on the low-torque damper 99 is amplified via the first gear 94 to the fifth gear 98 and acts on the rotation of the bracket 82.

[0166] As a result, when the engaging pin 77 moves within the resistance section 910, in addition to the resistance from the resistance section 910, a limiting torque amplified by the first gear 94 to the fifth gear 98, based on the low-torque damper 99, also acts. Therefore, even when the user forcefully pushes the paper tray 51 into the device body 1a, the pulling force of the engaging pin 77 is significantly reduced by the resistance section 910, and the rotational torque of the bracket 82 is limited, thus applying a braking effect to the pushing action of the paper tray 51.

[0167] Then, as Figure 17 As shown, the engaging pin 77 moves towards the promoting portion 914 via the middle portion 913 of the guide groove 91. The promoting portion 914 of the guide groove 91 is linear and is positioned away from the rotation axes 825 and 826 of the bracket 82. Therefore, a sufficient counterclockwise rotational torque is applied to the engaging pin 77 passing through the promoting portion 914 of the guide groove 91 by the slightly elongated helical spring 83. Thus, the engaging pin 77 can be reliably pulled into the end of the promoting portion 914 of the guide groove 91.

[0168] Therefore, according to the sheet receiving device 50 of this embodiment 1, compared with the case where the guide groove 91 of the pulling device 80 does not have a resistance part 910, even when the paper supply tray 51 is forcefully pushed into the interior of the device body 1a, sufficient braking force can be applied to the paper supply tray 51.

[0169] Furthermore, according to the sheet receiving device 50 of this embodiment 1, compared with the case where the guide groove 91 of the pulling device 80 does not have a promoting part 914, the pulling force acting on the paper supply tray 51 is not insufficient, and the paper supply tray 51 can be reliably pulled into the interior of the device body 1a.

[0170] Comparative example Figure 18 This is a structural diagram representing a comparative example.

[0171] In this comparative example, the end of the guide groove 91 on the inlet side is formed in a straight line along the pull-in direction. Therefore, the following technical problem exists: when the paper supply tray 51 is forcefully pushed in, it is impossible to decelerate, and the low torque damper does not function.

[0172] [Implementation Method 2]

[0173] Figure 19 This is a structural diagram showing the sheet receiving device according to Embodiment 2.

[0174] In the sheet receiving device according to Embodiment 2, the shape of the guide groove is different from that in Embodiment 1.

[0175] That is, in the sheet receiving device 50 according to Embodiment 2, such as Figure 19 As shown, the resistance part 910 of the guide groove 91 is composed of bending parts 911a and 911b that bend multiple times (twice in the example) in the pulling direction of the paper supply tray 51, and a single bending part 912.

[0176] Thus, in the sheet receiving device 50 according to Embodiment 2, the resistance part 910 of the guide groove 91 is configured to consist of a plurality of bent parts 911c, 911d and a bent part 912, thereby increasing the resistance acting on the connecting pin 77 and sufficiently slowing down the pulling speed of the paper supply tray 51.

[0177] Other structures and functions are the same as in Embodiment 1, therefore their descriptions are omitted.

[0178] Furthermore, in the above embodiment, the case of forming an image by electrophotography as an image forming apparatus has been described, but it is not limited to this, and the image may also be formed by other methods such as inkjet printing.

[0179] Furthermore, in the described embodiment, the sheet holding device is applied to the image forming apparatus, but it is not limited to this. Of course, the sheet holding device can also be applied to other devices such as a paper feeding device for paper feeding.

[0180] Furthermore, in the described embodiment, the case in which the connecting pin is provided on the device body and the pull-in device is arranged on the paper supply tray is explained, but it is not limited to this, and it is also possible to configure the connecting pin to be provided on the paper supply tray and the pull-in device to be arranged on the device body.

[0181] (Postscript) (((1)))

[0183] A sheet receiving device comprising:

[0184] A sheet housing that holds the sheet and can be pulled out and pulled in and installed on the main body of the device;

[0185] The joining mechanism is disposed in either the device body or the sheet housing; and

[0186] A pull-in mechanism, disposed in another of the device body or the sheet container, has a guide groove that engages with the engagement mechanism to guide the pull-in action of the sheet container, and a resistance part is provided in the guide groove to cause resistance to the pull-in action of the sheet container. (((2)))

[0188] According to the sheet receiving device described in ((1)), wherein,

[0189] The resistance element is positioned at the beginning of the pull-in action of the guide groove onto the sheet housing. (((3)))

[0191] According to the sheet receiving device described in ((2)), wherein,

[0192] The resistance section is formed by a region that causes the guide groove to bend and / or curve in the pulling direction of the sheet housing. (((4)))

[0194] According to the sheet receiving device described in ((3)), wherein,

[0195] The resistance section is composed of a region that is bent multiple times in the pulling direction of the sheet housing. (((5)))

[0197] According to the sheet receiving device described in ((1)), wherein,

[0198] The guide groove is provided with a facilitating part to promote the pulling-in action of the sheet accommodating body. (((6)))

[0200] According to the sheet receiving device described in ((5)), wherein,

[0201] The promoting part is disposed at the end of the pulling action of the guide groove into the sheet container. (((7)))

[0203] According to the sheet receiving device described in ((6)), wherein,

[0204] The promoting section is composed of a region in which the guide groove is formed into a straight line. (((8)))

[0206] According to the sheet receiving device described in ((5)), wherein,

[0207] The guide groove has a curved portion between the resistance portion and the promoting portion, which bends in a direction that intersects with the pulling direction of the sheet accommodating body. ((9)))

[0209] According to the sheet receiving device described in ((8)), wherein,

[0210] The curved portion is formed as an arc with a specified radius of curvature. (((10)))

[0212] An image forming apparatus comprising:

[0213] Sheet receiving mechanism, for receiving sheet; and

[0214] An image forming mechanism forms an image on the sheet.

[0215] The sheet receiving device described in any one of (((1))) to (((9))) is used as the sheet receiving mechanism.

[0216] According to the sheet receiving device involved in (((1))), compared with the case where there is no resistance part in the guide groove of the pulling mechanism, the pulling force of the sheet receiving body that is installed in the main body of the device can be adjusted.

[0217] According to the sheet receiving device involved in ((2)), compared with the case where the resistance part is located further back than the starting end of the pull-in action of the guide groove on the sheet receiving body, it is possible to resist the excessive pushing force on the sheet receiving body earlier.

[0218] According to the sheet receiving device involved in ((3)), compared with the case where the guide groove is formed in a straight line in the pulling direction of the sheet receiving body by the resistance action part, the resistance can be effectively applied to the sheet receiving body.

[0219] According to the sheet receiving device involved in ((4)), compared with the case where the resistance part is formed by a single bending area in the pulling direction of the sheet receiving body, the resistance can be applied to the sheet receiving body more effectively.

[0220] According to the sheet receiving device involved in ((5)), compared with the case where the guide groove does not have a promoting part, the sheet receiving body can be reliably pulled in.

[0221] According to the sheet receiving device involved in ((6)), compared with the case where the promoting part is located on the upstream side more than the middle of the pulling action, the sheet receiving body can be reliably pulled into the predetermined position.

[0222] According to the sheet receiving device involved in ((7)), compared with the case where the guide groove of the promoting part is formed into a curved shape, it can effectively play the role of pulling in.

[0223] According to the sheet receiving device involved in ((8)), compared with the case where a promoting part is continuously provided in the guide groove along with the resistance part, it is possible to smoothly transition from the effect of resistance on the sheet receiving body to the effect of promoting force on the sheet receiving body.

[0224] According to the sheet receiving device involved in (9), compared with the case where the curved part is formed into an arc shape with a changing radius of curvature, a roughly constant pulling force can be applied to the sheet receiving body.

[0225] According to the image forming apparatus described in (((10))), compared to the case where the sheet receiving device described in any one of (((1))) to (((9))) is not used as a sheet receiving mechanism, the pulling force of the sheet receiving body that is pulled out and pulled in to the main body of the apparatus can be adjusted, thereby improving operability.

[0226] The embodiments of the present invention described above are provided for illustrative purposes. Furthermore, these embodiments do not encompass the entirety of the invention, nor do they limit the invention to the disclosed methods. It will be apparent to those skilled in the art that various modifications and variations will be readily understood. These embodiments were chosen and described to most readily explain the principles and applications of the invention. Thus, those skilled in the art can understand the invention through various modifications that are assumed to be optimized for specific uses of various embodiments. The scope of the invention is defined by the foregoing claims and their equivalents.

Claims

1. A sheet receiving device, comprising: A sheet housing that holds the sheet and can be pulled out and pulled in and installed on the main body of the device; The joining mechanism is disposed in either the device body or the sheet housing; and A pull-in mechanism, disposed in another of the device body or the sheet container, has a guide groove that engages with the engagement mechanism to guide the pull-in action of the sheet container, and a resistance part is provided in the guide groove to cause resistance to the pull-in action of the sheet container.

2. The sheet receiving device according to claim 1, wherein, The resistance element is positioned at the beginning of the pull-in action of the guide groove onto the sheet housing.

3. The sheet receiving device according to claim 2, wherein, The resistance section is formed by a region that causes the guide groove to bend and / or curve in the pulling direction of the sheet housing.

4. The sheet receiving device according to claim 3, wherein, The resistance section is composed of a region that is bent multiple times in the pulling direction of the sheet housing.

5. The sheet receiving device according to claim 1, wherein, The guide groove is provided with a facilitating part to promote the pulling-in action of the sheet accommodating body.

6. The sheet receiving device according to claim 5, wherein, The promoting part is disposed at the end of the pulling action of the guide groove into the sheet container.

7. The sheet receiving device according to claim 6, wherein, The promoting section is composed of a region in which the guide groove is formed into a straight line.

8. The sheet receiving device according to claim 5, wherein, The guide groove has a curved portion between the resistance portion and the promoting portion, which bends in a direction that intersects with the pulling direction of the sheet accommodating body.

9. The sheet receiving device according to claim 8, wherein, The curved portion is formed as an arc with a specified radius of curvature.

10. An image forming apparatus comprising: Sheet receiving mechanism, for receiving sheet; and An image forming mechanism forms an image on the sheet. The sheet receiving device according to any one of claims 1 to 9 is used as the sheet receiving mechanism.

Images