Sheet storage device and image forming apparatus

Abstract

The present invention provides a sheet storage device and an image forming apparatus that enable the driven gear teeth to smoothly engage with the drive gear teeth when the sheet storage container is inserted into the sheet storage device body, and that also reduce the pull-out load. [Solution] The sheet storage device 200 is configured such that a first virtual straight line γ1 passing through the first rotation axis α1 of the drive-side gear 231 and the second rotation axis α2 of the driven-side gear 241 is displaceable by the insertion and removal operation of the sheet storage container 220 to the sheet storage device body 210. When the sheet storage container 220 is inserted into the sheet storage device body 210, the first angle φ1 made between the first virtual straight line γ1 and the second virtual straight line γ2 along the insertion / removal direction S is greater than 0 degrees, and the second angle φ2 made between the first virtual straight line γ1 and the second virtual straight line γ2 at the point when the driven-side gear 241 is separated from the drive-side gear 231 is smaller than the first angle φ1.

Description

Technical Field

[0001] The present disclosure relates to a sheet storage device provided in an image forming apparatus such as a copying machine, a multifunction peripheral, a printer, and a facsimile apparatus, and an image forming apparatus.

Background Art

[0002] A sheet storage device generally includes a sheet storage container (paper feed cassette), and the sheet storage container is provided so as to be insertable and removable with respect to the sheet storage device main body.

[0003] As such a sheet storage device, there are a cross-direction insertion / removal type in which the sheet storage container is provided so as to be insertable and removable in an insertion / removal direction in a direction orthogonal to the sheet conveyance direction with respect to the sheet storage device main body, and a conveyance-direction insertion / removal type in which the sheet storage container is provided so as to be insertable and removable in an insertion / removal direction in the sheet conveyance direction with respect to the sheet storage device main body.

[0004] Further, as a sheet storage container, there is one having a sheet placement portion on which sheets are placed and a container-side driving force transmission mechanism that transmits a driving force for lifting up the sheet placement portion to the sheet placement portion. In this case, the sheet storage device main body has a drive source and a main body-side driving force transmission mechanism that transmits the driving force from the drive source to the container-side driving force transmission mechanism.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in a sheet storage device of the intersecting direction insertion / extraction type that lifts up the sheet placement section, the sheet storage container is inserted into and removed from the sheet storage device body in an insertion / extraction direction intersecting the transport direction. For example, the main body side drive force transmission mechanism and the container side drive force transmission mechanism may each be provided with a drive-side same-rotation parallel shaft gear and a driven-side same-rotation parallel shaft gear that meshes with the drive-side same-rotation parallel shaft gear when the sheet storage container is inserted into the sheet storage device body. Here, "same-rotation parallel shaft gear" refers to a gear in which an internal gear and an external gear mesh and rotate in the same direction such that the axes of the two gears that mesh with each other are coaxial.

[0007] On the other hand, in a sheet storage device of the transport direction insertion / extraction type that lifts up the sheet placement section, the sheet storage container is inserted into and removed from the sheet storage device body in the transport direction. For example, the drive side reversing parallel shaft gear and the driven side reversing parallel shaft gear may be provided in the main body side drive force transmission mechanism and the container side drive force transmission mechanism, respectively. Here, "reversing parallel shaft gear" refers to a gear in which the external gears of two gears that mesh with each other mesh so that their axes are parallel and they rotate in opposite directions. A typical example is a spur gear.

[0008] In a sheet storage device of the intersecting direction insertion / removal type, the drive-side same-rotating parallel shaft gear and the driven-side same-rotating parallel shaft gear mesh with each other, so the load when pulling the sheet storage container out of the sheet storage device body is such that it does not hinder the removal operation.

[0009] In contrast, in a sheet storage device of the conveying direction insertion / removal type, the external gears of the drive-side reversing parallel shaft gear and the driven-side reversing parallel shaft gear mesh with each other, resulting in the following disadvantages.

[0010] Figure 12 is a schematic diagram illustrating a reference example of a sheet storage device 200X designed to minimize the extraction load when the sheet storage container 220X is pulled out from the sheet storage device body 210X. Figure 13 is a schematic diagram illustrating a reference example of a sheet storage device 200X designed so that the driven gear tooth meshing portion 241aX smoothly engages with the drive gear tooth meshing portion 231aX when the sheet storage container 220X is inserted into the sheet storage device body 210X.

[0011] The sheet storage device 200X includes a sheet storage container 220X. The sheet storage container 220X has a sheet mounting section 221X (sheet mounting plate) and a container-side drive force transmission mechanism 240X. The sheet mounting section 221X is on which the sheet P is placed. The container-side drive force transmission mechanism 240X transmits a driving force to the sheet mounting section 221X to lift it up. As a result, the sheet mounting section 221X can be lifted up by the driving force transmitted from the container-side drive force transmission mechanism 240X, and consequently, the leading edge (the downstream end in the transport direction W) of the sheet P placed on the sheet mounting section 221X can be positioned upward. In this example, the sheet mounting section 221X rotates around a first rotation axis β1 perpendicular to the transport direction W of the sheet P. The sheet storage container 220X further includes a push-up member 222X. The lifting member 222X is located below the sheet mounting section 221X and rotates around the second rotation axis β2 along the first rotation axis β1 to push up the sheet mounting section 221X. As a result, the container-side drive force transmission mechanism 240X can transmit the driving force to the sheet mounting section 221X via the lifting member 222X to lift up the sheet mounting section 221X.

[0012] The sheet storage device body 210X includes a drive source 213X and a body-side drive force transmission mechanism 230X. The body-side drive force transmission mechanism 230X transmits the drive force from the drive source 213X to the container-side drive force transmission mechanism 240X.

[0013] The sheet storage container 220X is provided so as to be insertable and removable from the sheet storage device body 210X in the insertion / removal direction S in the transport direction W.

[0014] The main body drive force transmission mechanism 230X has a drive-side reversing type parallel shaft gear (hereinafter simply referred to as the drive-side gear in this section) 231X to which the drive force is transmitted.

[0015] The container-side drive force transmission mechanism 240X has a driven-side reversing parallel shaft gear (hereinafter simply referred to as the driven-side gear in this section) 241X that can mesh with the drive-side gear 231X when the sheet storage container 220X is inserted into the sheet storage device body 210X.

[0016] When the sheet storage container 220X is inserted into the sheet storage device body 210X and the sheet mounting section 221X is lifted up, the drive-side gear 231X is unable to rotate due to the deactivation of the drive source 213X, and at least the load of the sheet mounting section 221X is applied to the driven-side gear 241X via the container-side drive force transmission mechanism 240X.

[0017] Here, as shown in Figure 12, if the sheet storage device 200X is configured such that the angle between the first virtual straight line γ1 passing through the first rotation axis α1 of the drive-side gear 231X and the second rotation axis α2 of the driven-side gear 241X and the second virtual straight line γ2 along the insertion / removal direction S is 0 degrees (they overlap), then the drive-side gear tooth meshing portion 231aX and the driven-side gear tooth meshing portion 241aX at the point where the drive-side gear 231X and the driven-side gear 241X mesh is parallel or approximately parallel to the insertion / removal direction S of the sheet storage container 220X. Therefore, when the sheet storage container 220X is inserted into the sheet storage device body 210X and the sheet mounting section 221X is lifted up, the drive-side gear 231X is in a non-rotatable state, and even if a load is applied to the driven-side gear 241X, the pull-out load when the sheet storage container 220X is pulled out of the sheet storage device body 210X is the smallest.

[0018] However, in this configuration, when the sheet storage container 220X is inserted into the sheet storage device body 210X, if the drive-side gear tooth meshing portion 231aX and the driven-side gear tooth meshing portion 241aX are facing each other, the driven-side gear tooth meshing portion 241aX will collide with the drive-side gear tooth meshing portion 231aX, and therefore the driven-side gear tooth meshing portion 241aX cannot smoothly mesh with the drive-side gear tooth meshing portion 231aX.

[0019] Therefore, as shown in Figure 13, the sheet storage device 200X is configured such that the first virtual line γ1 is angled φ with respect to the second virtual line γ2 (angle φ>0), which allows the drive-side gear tooth meshing portion 231aX and the driven-side gear tooth meshing portion 241aX to be positioned obliquely with respect to the insertion / removal direction S. This allows the driven-side gear tooth meshing portion 241aX to be inserted into the sheet storage device body 210X at an oblique angle, thereby enabling the driven-side gear tooth meshing portion 241aX to smoothly mesh with the drive-side gear tooth meshing portion 231aX.

[0020] However, in a configuration where the drive-side gear meshing portion 231aX and the driven-side gear meshing portion 241aX are positioned at an angle with respect to the insertion / removal direction S, the drive-side gear 231X is unable to rotate, and a load is applied to the driven-side gear 241X. As the angle φ between the first virtual line γ1 and the second virtual line γ2 increases, the gear meshing force of the driven-side gear meshing portion 241aX against the drive-side gear meshing portion 231aX increases when the sheet storage container 220X is pulled out of the sheet storage device body 210X, and the pulling load increases accordingly.

[0021] In this regard, Patent Document 1 discloses a sheet storage device having a gear-side arm that escapes when the phases of the drive gear and the sector gear are misaligned. However, this does not resolve the inconveniences related to the engagement of the driven gear teeth in the sheet storage container with the drive gear teeth in the sheet storage device body when inserting or removing the sheet storage container from the sheet storage device body.

[0022] Therefore, an object of the present disclosure is to provide a sheet storage device and an image forming apparatus that can smoothly mesh a driven-side gear tooth meshing portion with a driving-side gear tooth meshing portion when a sheet storage container is inserted into the sheet storage device main body, and can reduce the pulling load when the sheet storage container is pulled out from the sheet storage device main body.

Means for Solving the Problems

[0023] In order to solve the above problems, a sheet storage device according to the present disclosure includes a sheet placement portion for placing sheets, and a container-side driving force transmission mechanism for transmitting a driving force for lifting up the sheet placement portion to the sheet placement portion, and includes a sheet storage container having the above, and the sheet storage container is provided so as to be insertable and removable in the insertion and removal direction in the sheet conveyance direction with respect to a sheet storage device main body having a driving source and a main body-side driving force transmission mechanism for transmitting the driving force from the driving source to the container-side driving force transmission mechanism. The main body-side driving force transmission mechanism has a driving-side reverse-type parallel shaft gear to which the driving force is transmitted, and the container-side driving force transmission mechanism has a driven-side reverse-type parallel shaft gear that can mesh with the driving-side reverse-type parallel shaft gear when the sheet storage container is inserted into the sheet storage device main body. A first virtual straight line passing through a first rotation axis of the driving-side reverse-type parallel shaft gear and a second rotation axis of the driven-side reverse-type parallel shaft gear is configured to be displaceable by an insertion and removal operation of the sheet storage container with respect to the sheet storage device main body, and a first angle formed by the first virtual straight line and a second virtual straight line along the insertion and removal direction when the sheet storage container is inserted into the sheet storage device main body is larger than 0 degrees, and a second angle formed by the first virtual straight line and the second virtual straight line when the sheet storage container is pulled out from the sheet storage device main body and the driven-side reverse-type parallel shaft gear is separated from the driving-side reverse-type parallel shaft gear is smaller than the first angle.

[0024] Further, an image forming apparatus according to the present disclosure includes the sheet storage device according to the present disclosure.

Effects of the Invention

[0025] According to the present disclosure, when the sheet storage container is inserted into the sheet storage device main body, the driven-side gear tooth engagement portion can be smoothly engaged with the driving-side gear tooth engagement portion, and the pulling load when the sheet storage container is pulled out from the sheet storage device main body can be reduced.

Brief Description of the Drawings

[0026] [Figure 1] It is a cross-sectional view showing an image forming apparatus according to the present embodiment. [Figure 2] In the sheet storage device, it is a perspective view seen from obliquely above the front side of a state where an example of the sheet storage container is pulled out from the sheet storage device main body. [Figure 3] In the sheet storage device, it is a perspective view seen from obliquely below the front side of a state where an example of the sheet storage container is pulled out from the sheet storage device main body. [Figure 4] In the sheet storage device, it is a schematic diagram schematically showing a state where the sheet storage container is inserted into the sheet storage device main body. [Figure 5] It is a front view showing the main body side driving force transmission mechanism in a state where the sheet storage container is pulled out from the sheet storage device main body. [Figure 6] It is a front view showing the meshing state of the driven-side gear and the driving-side parallel shaft gear when the sheet storage container is inserted into the sheet storage device main body. [Figure 7] It is a front view showing the state of the driven-side parallel shaft gear and the driving-side parallel shaft gear when the sheet storage container is pulled out from the sheet storage device main body and the driven-side parallel shaft gear is separated from the driving-side parallel shaft gear. [Figure 8] It is a perspective view seen from the back side of the driving-side parallel shaft gear, the upstream-side parallel shaft gear, the support member, the driven-side gear, and the arc-shaped gear. [Figure 9] It is a perspective view seen from the back side of an example of a restricting portion that restricts the swinging of the support member. [Figure 10] It is a rear view seen from the back side of an example of a restricting portion that restricts the swinging of the support member. [Figure 11]This is a rear view of another example of a restricting mechanism that limits the oscillation of a support member, viewed from the rear. [Figure 12] This is a schematic diagram illustrating a reference example of a sheet storage device designed to minimize the pulling load when the sheet storage container is pulled out from the sheet storage device body. [Figure 13] This is a schematic diagram illustrating a reference example of a sheet storage device in which the driven gear teeth meshing portion smoothly engages with the driving gear teeth meshing portion when the sheet storage container is inserted into the sheet storage device body. [Modes for carrying out the invention]

[0027] The embodiments of this disclosure will be described below with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

[0028] (Image forming apparatus) Figure 1 is a cross-sectional view showing an image forming apparatus 100 according to this embodiment. In the figure, the left-right direction is denoted as X, the right side as X1, and the left side as X2. The direction perpendicular to the left-right direction X is denoted as the depth direction Y, the front side as Y1, and the back side as Y2. The vertical direction perpendicular to the left-right direction X and the depth direction Y is denoted as Z. The following explanation will be given accordingly.

[0029] The image data handled by the main body 110 of the image forming apparatus 100 corresponds to either a color image using black (K), cyan (C), magenta (M), and yellow (Y), or a monochrome image using a single color (e.g., black). For this reason, four photoreceptor drums 1 (an example of an image carrier), chargers 2, print heads 3, developing units 4, primary transfer units 5, and drum cleaning units 6 are provided to form four types of toner images corresponding to each color, and these are associated with black, cyan, magenta, and yellow, respectively, forming four image stations Pa, Pb, Pc, and Pd. Note that the image forming apparatus 100 may also be a monochrome image forming apparatus.

[0030] At each image station Pa, Pb, Pc, and Pd, the chargers 2-2 uniformly charge the surface 1a of the photoreceptor drums 1-1, which are rotated in a predetermined rotation direction R, to a predetermined potential. The print heads 3-3 expose the surface 1a of the photoreceptor drums 1-1, forming an electrostatic latent image on the surface 1a of the photoreceptor drums 1-1. The developing device 4 develops the electrostatic latent image on the surface 1a of the photoreceptor drums 1-1, forming a toner image on the surface 1a of the photoreceptor drums 1-1. As a result, toner images of each color are formed on the surface 1a of each photoreceptor drum 1-1. The drum cleaning devices 6-6 remove and recover residual toner from the surface 1a of the photoreceptor drums 1-1. The primary transfer devices 5-5 sequentially transfer the toner images of each color on the surface 1a of each photoreceptor drum 1-1 onto an intermediate transfer belt 23 that moves circulating by the drive rollers 21 and driven rollers 22 of the belt drive device 20, forming a color toner image on the intermediate transfer belt 23. The belt cleaning device 7 removes and recovers residual toner from the intermediate transfer belt 23.

[0031] A transfer nip section TN is formed between the intermediate transfer belt 23 and the transfer roller 81 of the secondary transfer device 8. The transfer roller 81 of the secondary transfer device 8 traps the sheet P, such as recording paper, which has been transported through the sheet transport path 11, in the transfer nip section TN and transports it together with the intermediate transfer belt 23, while transferring the color toner image on the surface of the intermediate transfer belt 23 onto the sheet P. The fixing device 9 traps the sheet P between a fixing member (fixing belt 91 in this example) and a pressurizing member (pressure roller 92 in this example), heats and pressurizes it, and fixes the color toner image on the sheet P.

[0032] The sheet P is pulled out from the sheet storage device 200 by the pickup roller 12, transported through the sheet transport path 11, passes through the secondary transfer device 8 and the fixing device 9, and is delivered to the discharge tray 15 via the discharge roller 31. The sheet transport path 11 is equipped with a registration roller 16 and the like. The registration roller 16 temporarily stops the sheet P, aligns the leading edge of the sheet P, and then starts transporting the sheet P in accordance with the timing of the toner image transfer at the transfer nip section TN between the intermediate transfer belt 23 and the transfer roller 81. The sheet P is transported along the sheet transport path 11 with the center of the image forming apparatus body 110 as the reference point (center reference) in the direction of the rotation axis (left-right direction X) of the photoreceptor drums 1 to 1.

[0033] Figures 2 and 3 are perspective views of the sheet storage device 200, showing an example of a sheet storage container 220 being pulled out from the sheet storage device body 210, viewed from the front, diagonally above and diagonally below, respectively. In Figure 3, the cover member covering the main body-side drive force transmission mechanism 230 has been removed. Figure 4 is a schematic diagram illustrating the state in which the sheet storage container 220 is inserted into the sheet storage device body 210 in the sheet storage device 200.

[0034] As shown in Figures 2 to 4, the sheet storage device 200 includes a sheet storage container 220 (paper feed cassette). The sheet storage container 220 has a sheet mounting section 221 (see Figures 2 and 4) (sheet mounting plate) and a container-side drive force transmission mechanism 240 (see Figures 2 and 4). The sheet mounting section 221 is on which the sheet P is placed. The container-side drive force transmission mechanism 240 transmits a driving force to the sheet mounting section 221 to lift it up. This allows the sheet mounting section 221 to be lifted up by the driving force transmitted from the container-side drive force transmission mechanism 240, and consequently, the leading edge (downstream end in the transport direction W) of the sheet P placed on the sheet mounting section 221 can be positioned upward. In this example, the sheet mounting section 221 rotates around a first rotation axis β1 perpendicular to the transport direction W of the sheet P. Here, rotation refers to rotation of 360 degrees or more, and rotation refers to rotation of less than 360 degrees. The sheet storage container 220 further has a push-up member 222. The push-up member 222 is located below the sheet mounting section 221 and rotates around a second rotation axis β2 along a first rotation axis β1 to push up the sheet mounting section 221. As a result, the container-side drive force transmission mechanism 240 can transmit a driving force to the sheet mounting section 221 via the push-up member 222 to lift up the sheet mounting section 221.

[0035] The sheet storage device body 210 includes a drive source 213 (see Figure 4) (stepping motor) and a body-side drive force transmission mechanism 230 (see Figures 3 and 4). The body-side drive force transmission mechanism 230 transmits the drive force from the drive source 213 to the container-side drive force transmission mechanism 240 when the sheet storage container 220 is inserted into the sheet storage device body 210.

[0036] The sheet storage container 220 is provided so as to be insertable and removable from the sheet storage device body 210 in the insertion / removal direction S in the transport direction W.

[0037] The main body-side drive force transmission mechanism 230 has a drive-side reversing type parallel shaft gear (hereinafter simply referred to as the drive-side gear in this section) 231 (see Figures 3 and 4) to which the drive force is transmitted.

[0038] The container-side drive force transmission mechanism 240 has a driven-side reversing parallel shaft gear (hereinafter simply referred to as the driven-side gear in this section) 241 (see Figures 2 and 4) that can mesh with the drive-side gear 231 when the sheet storage container 220 is inserted into the sheet storage device body 210.

[0039] More specifically, the drive source 213 is provided in the sheet storage device body 210 and transmits the driving force from the body-side drive force transmission mechanism 230 and the container-side drive force transmission mechanism 240 to the sheet mounting section 221 via the push-up member 222.

[0040] In other words, the sheet mounting section 221 is provided on the sheet storage container 220 so as to be rotatable around a first rotation axis β1 along the left-right direction X (width direction) perpendicular to the conveying direction W of the sheet P (with the first rotation axis 211 as the pivot point). The sheet storage container 220 houses the sheet P placed on the sheet mounting section 221. The push-up member 222 is provided on the sheet storage container 220 so as to be rotatable around a second rotation axis β2 (with the second rotation axis 212 as the pivot point) below the tip side of the sheet mounting section 221 (downstream of the center in the conveying direction W). As a result, the push-up member 222 can move the tip side of the sheet mounting section 221 from the lower limit position to the upper limit position (sheet supply position) by rotating around the second rotation axis β2.

[0041] Figure 5 is a front view showing the main body-side drive force transmission mechanism 230 when the seat storage container 220 is withdrawn from the seat storage device body 210. Figure 6 is a front view showing the meshing state of the driven gear 241 and the drive gear 231 when the seat storage container 220 is inserted into the seat storage device body 210. Figure 7 is a front view showing the state of the driven gear 241 and the drive gear 231 at the point when the seat storage container 220 is withdrawn from the seat storage device body 210 and the driven gear 241 separates from the drive gear 231.

[0042] The main body drive force transmission mechanism 230 includes a drive-side gear train 230a consisting of a plurality of main body gears. In this example, the drive-side gear train 230a consists of a drive-side gear 231, an upstream reversing parallel shaft gear (hereinafter simply referred to as the upstream gear in this section) 232, an intermediate reversing parallel shaft gear (hereinafter simply referred to as the intermediate gear) 233, and a motor reversing parallel shaft gear (hereinafter simply referred to as the motor gear) 234.

[0043] The motor gear 234 receives the driving force from the rotating shaft 213a (see Figure 4) of the drive source 213. The intermediate gear 233 meshes with the motor gear 234 and the upstream gear 232 to transmit the driving force from the motor gear 234 to the upstream gear 232. The intermediate gear 233 and the motor gear 234 are rotatably supported on the main frame FL of the seat housing device body 210. The upstream gear 232 meshes with the intermediate gear 233 and the drive-side gear 231 to transmit the driving force from the intermediate gear 233 to the drive-side gear 231.

[0044] The drive-side gear 231 meshes with the upstream-side gear 232 and the driven-side gear 241 in the container-side drive force transmission mechanism 240 when the sheet storage container 220 is inserted into the sheet storage device body 210, and transmits the driving force from the upstream-side gear 232 to the driven-side gear 241. The driven-side gear 241 is rotatably supported on the outer surface of the sheet storage container 220.

[0045] The container-side drive force transmission mechanism 240 includes a driven-side gear train 240a consisting of a plurality of container-side gears. In this example, the driven-side gear train 240a consists of a driven-side gear 241 and an arc-shaped reversing parallel shaft gear (hereinafter simply referred to as an arc-shaped gear) 242.

[0046] The driven gear 241 meshes with the drive gear 231 and the arc-shaped gear 242 in the main body drive force transmission mechanism 230 when the sheet storage container 220 is inserted into the sheet storage device body 210, and transmits the driving force from the drive gear 231 to the arc-shaped gear 242. The arc-shaped gear 242 is fixed to the second rotation axis 212 of the push-up member 222. The arc-shaped gear 242 transmits the driving force from the driven gear 241 to the second rotation axis 212 of the push-up member 222. As a result, when the sheet storage container 220 is inserted into the sheet storage device body 210, the drive source 213 rotates, causing the push-up member 222 to rotate around the second rotation axis β2 via the drive gear 231 and the driven gear 241, and consequently the tip of the sheet mounting section 221 to be raised around the first rotation axis β1. On the other hand, when the sheet storage container 220 is pulled out from the sheet storage device body 210, the engagement between the drive-side gear 231 and the driven-side gear 241 is released, thereby releasing the upward push of the push-up member 222 towards the sheet mounting section 221, and the tip of the sheet mounting section 221 descends.

[0047] In this state, when the sheet storage container 220 is inserted into the sheet storage device body 210 and the sheet mounting section 221 is lifted up, the drive-side gear 231 is unable to rotate due to the deactivation of the drive source 213, and at least the load of the sheet mounting section 221 is applied to the driven-side gear 241 via the container-side drive force transmission mechanism 240.

[0048] In the conveying direction insertion / removal type sheet storage device 200, the drive-side gear 231 and the driven-side gear 241 have external gears that mesh with each other, so if left as is, the pull-out load on the sheet storage container 220 will be large. That is, as the angle φ between the first virtual straight line γ1 passing through the first rotation axis α1 and the second rotation axis α2 and the second virtual straight line γ2 along the insertion / removal direction S of the sheet storage container 220 increases, the gear meshing force of the driven-side gear tooth meshing portion 241a against the drive-side gear tooth meshing portion 231a when the sheet storage container 220 is pulled out of the sheet storage device body 210 increases, and the pull-out load increases accordingly. Here, "gear tooth meshing portion" refers to the part of the gear teeth that mesh with each other and are in contact.

[0049] (Regarding this embodiment) In this respect, in this embodiment, the first virtual straight line γ1 is configured to be displaceable by inserting and removing the sheet storage container 220 from the sheet storage device body 210.

[0050] When the sheet storage container 220 is inserted into the sheet storage device body 210, the first angle φ1 between the first virtual line γ1 and the second virtual line γ2 is greater than 0 degrees.

[0051] At the point when the seat storage container 220 is pulled out from the seat storage device body 210 and the driven gear 241 separates from the drive gear 231, the second angle φ2 formed by the first virtual line γ1 and the second virtual line γ2 is smaller than the first angle φ1.

[0052] In this embodiment, the sheet storage device 200 is configured such that when the sheet storage container 220 is inserted into the sheet storage device body 210, the first virtual line γ1 is oblique to the second virtual line γ2 (first angle φ1 > 0). This allows the direction of the drive-side gear tooth meshing portion 231a and the driven-side gear tooth meshing portion 241a to be oblique to the insertion / removal direction S. As a result, when the sheet storage container 220 is inserted into the sheet storage device body 210, the driven-side gear tooth meshing portion 241a can be inserted into the drive-side gear tooth meshing portion 231a at an angle, thereby allowing the driven-side gear tooth meshing portion 241a to smoothly mesh with the drive-side gear tooth meshing portion 231a.

[0053] Furthermore, the angle φ between the first virtual line γ1 and the second virtual line γ2 when the sheet storage container 220 is inserted into the sheet storage device body 210 is a first angle φ1 that is greater than 0 degrees and less than 90 degrees. The first angle φ1 is not limited to this, but can be exemplified as being around 25 to 35 degrees. In this example, the first angle φ1 is set to 30 degrees.

[0054] When the sheet storage container 220 is inserted into the sheet storage device body 210, and the operator initiates a withdrawal operation of the sheet storage container 220 from the sheet storage device body 210, the drive-side gear 231 and the driven-side gear 241 displace while remaining meshed and in contact. As the drive-side gear 231 and the driven-side gear 241 displace, the angle φ between the first virtual line γ1 and the second virtual line γ2 becomes smaller than the first angle φ1, and the second angle φ2 (<φ1) is reached when the driven-side gear 241 separates from the drive-side gear 231 after the withdrawal operation of the sheet storage container 220 from the sheet storage device body 210 has begun. The second angle φ2 is not limited to this, but can be exemplified as being around 20 to 25 degrees. In this example, the second angle φ2 is set to 23.5 degrees. The angle φ is obtained when the drive gear 231 moves in the pulling direction S2, pulled along by the driven gear 241, from the first angle φ1, and moves in the pulling direction S2, pulling along the drive gear 241, resulting in the second angle φ2.

[0055] In this case, with respect to the withdrawal direction S2 of the sheet storage container 220, the angle between the direction of the drive-side gear tooth meshing portion 231a and the driven-side gear tooth meshing portion 241a at the point where the drive-side gear 231 and the driven-side gear 241a mesh (first virtual line γ1) and the insertion / removal direction S (second virtual line γ2) becomes gentler. As a result, the gear meshing force of the driven-side gear tooth meshing portion 241a against the drive-side gear tooth meshing portion 231a when the sheet storage container 220 is pulled out of the sheet storage device body 210 becomes smaller, and the operator can pull out the sheet storage container 220 from the sheet storage device body 210 with less force. In other words, the gear meshing force of the driven-side gear tooth meshing portion 241a against the drive-side gear tooth meshing portion 231a when the sheet storage container 220 is pulled out of the sheet storage device body 210 can be reduced, and the pulling load can be reduced accordingly.

[0056] Therefore, when the sheet storage container 220 is inserted into the sheet storage device body 210, the driven gear tooth meshing portion 241a can smoothly engage with the drive gear tooth meshing portion 231a, and the pulling load when the sheet storage container 220 is pulled out from the sheet storage device body 210 can be reduced.

[0057] In this embodiment, as the sheet storage device 200 is pulled out of the sheet storage container 220 and the driven gear 241 moves in the separation direction, which is the pulling direction S2, away from the drive gear 231, the second angle φ2 gradually decreases from the first angle φ1.

[0058] In this way, as the driven gear 241 moves in the withdrawal direction S2 (separation direction), the second angle φ2 gradually decreases from the first angle φ1, allowing the operator to smoothly pull out the sheet storage container 220 from the sheet storage device body 210.

[0059] <First Embodiment> In this embodiment, the main body drive force transmission mechanism 230 further includes an upstream gear 232. The upstream gear 232 meshes with the drive gear 231. In the seat housing device 200, the upstream rotation axis α3 of the upstream gear 232 is located on the driven gear 241 side (pull-out direction S2 side) than the first virtual vertical line ε1 passing through the first rotation axis α1 of the drive gear 231.

[0060] As shown in Figure 6, when the sheet storage container 220 is inserted into the sheet storage device body 210, the second rotation axis α2 of the driven gear 241 is located on the insertion direction S1 side (drive gear 231 side) of the sheet storage container 220, relative to the second virtual vertical line ε2 passing through the upstream rotation axis α3 of the upstream gear 232.

[0061] In this configuration, when the sheet storage container 220 is inserted into the sheet storage device body 210, the driven gear tooth meshing portion 241a can engage with the drive gear tooth meshing portion 231a more smoothly.

[0062] Furthermore, as shown in Figure 7, when the sheet storage device 200 is pulled out of the sheet storage container 220 and the driven gear 241 moves away from the drive gear 231, the second rotation axis α2 is positioned on the side of the sheet storage container 220 in the pulling direction S2, relative to the second virtual vertical line ε2.

[0063] In this configuration, the pulling load when the sheet storage container 220 is pulled out from the sheet storage device body 210 can be further reduced.

[0064] <Second Embodiment> In this embodiment, as shown in Figure 6, the rotational trajectory λ of the outer circumference of the driven gear 241 is lower than the first rotation axis α1 of the drive gear 231 when the sheet storage container 220 is inserted into the sheet storage device body 210. That is, the rotational trajectory λ of the outer circumference of the driven gear 241 is located below the second virtual straight line γ2 that passes through the first rotation axis α1 when the sheet storage container 220 is inserted into the sheet storage device body 210.

[0065] In this configuration, when the sheet storage container 220 is inserted into the sheet storage device body 210, the driven gear tooth meshing portion 241a can engage with the drive gear tooth meshing portion 231a more smoothly.

[0066] Furthermore, as shown in Figure 7, the rotational trajectory λ of the outer circumference of the driven gear 241 is higher than the first rotation axis α1 of the drive gear 231 at the time when the sheet storage container 220 is pulled out from the sheet storage device body 210 and the driven gear 241 separates from the drive gear 231. In other words, the rotational trajectory λ of the outer circumference of the driven gear 241 is located above the second virtual straight line γ2 that passes through the first rotation axis α1 at the time when the sheet storage container 220 is pulled out from the sheet storage device body 210 and the driven gear 241 separates from the drive gear 231.

[0067] In this configuration, the pulling load when the sheet storage container 220 is pulled out from the sheet storage device body 210 can be further reduced.

[0068] <Third Embodiment> By the way, if the outer diameter of the driven gear 241 is larger than the outer diameter of the driving gear 231, the size of the sheet storage container 220 in the vertical Z direction will increase accordingly.

[0069] In this respect, in this embodiment, as shown in Figure 4, the outer diameter r2 of the driven gear 241 is smaller than the outer diameter r1 of the drive gear 231.

[0070] In this configuration, the outer diameter r2 of the driven gear 241 is smaller than the outer diameter r1 of the drive gear 231, which allows the size of the sheet storage container 220 in the vertical Z direction to be reduced accordingly.

[0071] <Fourth Embodiment> Figure 8 is a perspective view of the drive gear 231, the upstream gear 232 and the support member 235, as well as the driven gear 241 and the arc-shaped gear 242, viewed from the rear side.

[0072] In this embodiment, the main body-side drive force transmission mechanism 230 further includes a support member 235 (link plate). The support member 235 rotatably supports the drive-side gear 231 and the upstream-side gear 232 when they are meshed together, and is also capable of oscillating around a pivot axis δ that is coaxial with the upstream rotation axis α3 of the upstream-side gear 232 (with the pivot axis 235c as the fulcrum).

[0073] In this configuration, the drive gear 231 can be easily and reliably oscillated around the pivot axis δ relative to the upstream gear 232 while maintaining the rotational movement of the drive gear 231 and the upstream gear 232 by the support member 235. This makes it easy to realize a configuration in which the first virtual straight line γ1 can be displaced by inserting and removing the sheet storage container 220 from the sheet storage device body 210.

[0074] More specifically, the support member 235 comprises a support member body 2351, a first rotation axis 235a, a second rotation axis 235b, and a swing axis 235c. The support member body 2351 constitutes a plate-shaped swing arm portion extending along the direction of a third virtual straight line γ3 passing through the first rotation axis α1 and the upstream rotation axis α3. The first rotation axis 235a is erected on the drive-side gear 231 side of the support member body 2351. The drive-side gear 231 is provided on the support member body 2351 so as to be rotatable around the first rotation axis α1 (with the first rotation axis 235a as the pivot point). The second rotation axis 235b is erected on the upstream-side gear 232 side of the support member body 2351. The upstream gear 232 is mounted on the support member body 2351 so as to be rotatable around the upstream rotation axis α3 (with the second rotation axis 235b as the pivot point). The oscillating shaft 235c is erected on the support member body 2351 on the opposite side from the upstream gear 232, coaxial with the second rotation axis 235b. The support member body 2351 is supported on the main frame FL of the seat housing device body 210 so as to be rotatable around the oscillating axis δ (with the oscillating shaft 235c as the pivot point).

[0075] <Fifth Embodiment> Figures 9 and 10 are a perspective view and a rear view, respectively, of an example (236a) of a restricting part 236 that restricts the swinging of the support member 235, viewed from the rear side.

[0076] However, when the sheet storage container 220 is pulled out from the sheet storage device body 210, the engagement between the drive-side gear 231 and the driven-side gear 241 is disengaged, causing the support member 235 to swing in the pulling direction S2 around the oscillation axis δ by its own weight or a biasing member (in this example, its own weight), causing the drive-side gear 231 to move downward, and making it impossible to maintain the support member 235 in a position where the driven-side gear tooth engagement portion 241a can smoothly engage with the drive-side gear tooth engagement portion 231a. If this occurs, the driven-side gear tooth engagement portion 241a may not be able to smoothly engage with the drive-side gear tooth engagement portion 231a when the sheet storage container 220 is inserted into the sheet storage device body 210.

[0077] In this regard, the seat storage device 200 has a restricting section 236 (see Figures 9 and 10).

[0078] The restricting section 236 restricts the swing of the support member 235 in the pulling direction S2 around the swing axis δ when the sheet storage container 220 is pulled out from the sheet storage device body 210, by disengaging the drive gear 231 and the driven gear 241.

[0079] In this way, by restricting the swing of the support member 235 in the withdrawal direction S2 around the swing axis δ when the sheet storage container 220 is pulled out from the sheet storage device body 210, the support member 235 can be maintained in a position where the driven gear tooth meshing portion 241a smoothly engages with the drive gear tooth meshing portion 231a. Therefore, when the sheet storage container 220 is inserted into the sheet storage device body 210, the driven gear tooth meshing portion 241a can smoothly engage with the drive gear tooth meshing portion 231a.

[0080] <Fifth Embodiment-1> In this embodiment, the restricting portion 236 restricts the swing of the support member 235 from a first swing position at a first angle φ1 to a second swing position at a second angle φ2 when the sheet storage container 220 is pulled out from the sheet storage device body 210, in the direction of the pull-out S2.

[0081] In this configuration, when the sheet storage container 220 is pulled out from the sheet storage device body 210, the direction of the drive-side gear tooth meshing portion 231a and the driven-side gear tooth meshing portion 241a (second virtual straight line γ2) can be maintained at a second angle φ2 (23.5 degrees in this example) with respect to the insertion / removal direction S (first virtual straight line γ1). This makes it easier to insert the driven-side gear tooth meshing portion 241a into the drive-side gear tooth meshing portion 231a at an angle when the sheet storage container 220 is inserted into the sheet storage device body 210, and therefore the driven-side gear tooth meshing portion 241a can smoothly mesh with the drive-side gear tooth meshing portion 231a.

[0082] More specifically, the support member body 2351 is provided with a restricted portion 235d (see Figures 8, 9, and 10). The restricted portion 235d protrudes from the support member body 2351 on the side opposite to the drive-side gear 231 and the upstream-side gear 232. The main frame FL of the seat housing device body 210 is provided with a through hole FLa (Figures 9, 10, and 11) through which the restricted portion 235d passes. The restricting portion 236 includes a part of the through hole FLa. Specifically, the through hole FLa provided in the main frame FL has a pair of edges (236a, 236b) along the radial direction E centered on the oscillation axis δ. The restricting portion 236 includes a pair of edges (236a, 236b). One edge 236a is located below the restricted portion 235d and comes into contact with the restricted portion 235d due to the oscillation of the support member 235 in the first oscillation direction M1. At this time, the angle φ between the first rotation axis α1 and the second virtual straight line γ2 becomes the second angle φ2 (the angle at which it contacts the restricted portion 235d). The other edge portion 236b is located above the restricted portion 235d and contacts the restricted portion 235d due to the swing of the support member 235 in the second swing direction M2, which is opposite to the first swing direction M1. At this time, the angle φ between the first rotation axis α1 and the second virtual straight line γ2 becomes a predetermined third angle (the angle at which it contacts the restricted portion 235d) which is larger than the first angle φ1. In this example, the restricted portion 235d is formed by punching out a die from the support member body 2351 and then bending it to the opposite side from the drive-side gear 231 and the upstream-side gear 232.

[0083] <Fifth Embodiment-2> Figure 11 is a rear view of another example (236c) of the restricting part 236 that restricts the swinging of the support member 235, viewed from the rear side.

[0084] In this embodiment, the restricting portion 236 includes a biasing member 236c (a coil spring in this example). The biasing member 236c allows the support member 235 to swing from a first swing position at a first angle φ1 to a second swing position at a second angle φ2 when the sheet storage container 220 is pulled out from the sheet storage device body 210, and biases the support member 235 toward the insertion direction S1 when the engagement between the drive-side gear 231 and the driven-side gear 241 is released, so that the support member 235 returns to the first swing position and is maintained in the first swing position.

[0085] In this configuration, when the sheet storage container 220 is pulled out from the sheet storage device body 210, the biasing member 236c allows the operator to smoothly pull out the sheet storage container 220 from the sheet storage device body 210. Furthermore, even if the meshing between the drive-side gear 231 and the driven-side gear 241 is disengaged, the direction of the drive-side gear tooth meshing portion 231a and the driven-side gear tooth meshing portion 241a (second virtual straight line γ2) can be maintained at a first angle φ1 (30 degrees in this example) with respect to the insertion / removal direction S (first virtual straight line γ1). This makes it easier to insert the driven-side gear tooth meshing portion 241a into the drive-side gear tooth meshing portion 231a at an angle when the sheet storage container 220 is inserted into the sheet storage device body 210, and therefore the driven-side gear tooth meshing portion 241a can smoothly mesh with the drive-side gear tooth meshing portion 231a.

[0086] More specifically, the restricted portion 235d extends radially in the direction E. The main frame FL is provided with a locking portion FLb that extends radially in the direction E. The locking portion FLb is erected from the side of the main frame FL opposite to the support member 235. The biasing member 236c is provided between the restricted portion 235d and the locking portion FLb on the support member 235, and in its natural length maintains the support member 235 in the first swing position. In this example, the locking portion FLb is located below the restricted portion 235d and is compressed when allowing the support member 235 to swing from the first swing position to the second swing position.

[0087] <Sixth Embodiment> In this embodiment, the drive-side gear 231 is biased by its own weight or by a force component in the direction of contact with the driven-side gear 241 due to a biasing member (in this example, its own weight).

[0088] In this configuration, the drive-side gear tooth meshing portion 231a and the driven-side gear tooth meshing portion 241a can be made to mesh more easily.

[0089] This disclosure is not limited to the embodiments described above, and can be implemented in a variety of other ways. Therefore, these embodiments are merely illustrative in all respects and should not be constrained. The scope of this disclosure is defined by the claims and is not restricted by the text of the specification. Furthermore, any variations or modifications falling within the equivalent scope of the claims are all within the scope of this disclosure. [Explanation of Symbols]

[0090] 100 Image forming apparatus 200-sheet storage device 210 Sheet storage device main body 211 First moving axle 212 Second drive axle 213 Power source 213a Rotation axis 220-sheet storage container 221 Sheet mounting section 222 Push-up member 23 Intermediate transfer belt 230 Main unit side drive force transmission mechanism 230a Drive-side gear train 231 Drive-side gear (an example of a drive-side reversing parallel shaft gear) 231a Drive side gear tooth meshing portion 232 Upstream gear (an example of an upstream reverse-rotating parallel shaft gear) 233 Intermediate gear 234 Motor Gear 235 Support member 2351 Support member body 235a First rotation axis 235b Second rotation axis 235c oscillating axis 235d Regulated part 236 Regulatory Department 236a One edge 236b The other edge 236c Biasing member 240 Container-side driving force transmission mechanism 240a Driven gear train 241 Driven gear (an example of a driven reverse-rotating parallel shaft gear) 241a Driven gear tooth meshing portion 242 Arc-shaped gear E radial direction FL main frame FLa through hole FLb locking part P Sheet S Insertion / removal direction S1 Insertion direction S2 Pull-out direction W Conveying direction X Left / right direction Y (depth direction) Z vertical direction r1 Outer diameter r2 Outer diameter α1 First rotation axis α2 Second rotation axis α3 Upstream rotation axis β1 First Axis Line β2 Second Axis Line γ1 First virtual line γ2 Second virtual line γ3 Third virtual line δ oscillation axis ε1 First virtual vertical line ε2 Second virtual vertical line λ Rotation trajectory φ angle φ1 1st angle φ2 2nd angle

Claims

1. A sheet storage container comprising a sheet placement section for placing a sheet, and a container-side drive force transmission mechanism for transmitting a driving force to the sheet placement section for lifting the sheet placement section, The sheet storage device is provided so as to be insertable and removable in the insertion and removal direction in the transport direction of the sheet, with respect to a sheet storage device body having a drive source and a main body drive force transmission mechanism that transmits the drive force from the drive source to the container-side drive force transmission mechanism, The main body side drive force transmission mechanism has a drive side reversing type parallel shaft gear to which the drive force is transmitted, The container-side driving force transmission mechanism has a driven-side reversing-type parallel shaft gear that can mesh with the driving-side reversing-type parallel shaft gear when the sheet storage container is inserted into the sheet storage device body, The first virtual straight line passing through the first rotation axis of the drive-side reversing parallel shaft gear and the second rotation axis of the driven-side reversing parallel shaft gear is configured to be displaceable by inserting and removing the sheet storage container from the sheet storage device body. When the sheet storage container is inserted into the sheet storage device body, the first angle formed by the first virtual line and the second virtual line along the insertion / removal direction is greater than 0 degrees. A sheet storage device characterized in that the second angle formed by the first virtual line and the second virtual line at the time when the sheet storage container is pulled out from the sheet storage device body and the driven-side reversing parallel shaft gear separates from the drive-side reversing parallel shaft gear is smaller than the first angle.

2. A sheet storage device according to claim 1, A sheet storage device characterized in that the second angle gradually decreases from the first angle as the sheet storage container is pulled out from the sheet storage device body and the driven-side reversing parallel shaft gear moves in a direction away from the drive-side reversing parallel shaft gear, which is the direction in which the sheet storage container is pulled out.

3. A sheet storage device according to claim 1, The main body side drive force transmission mechanism further includes an upstream reverse-type parallel shaft gear that meshes with the drive side reverse-type parallel shaft gear, The upstream rotation axis of the upstream reversing parallel shaft gear is located on the driven reversing parallel shaft gear side of the first virtual vertical line passing through the first rotation axis of the drive reversing parallel shaft gear, When the sheet storage container is inserted into the sheet storage device body, the second rotation axis of the driven-side reversing parallel shaft gear is located on the insertion side of the sheet storage container, and the second virtual vertical line passing through the upstream rotation axis of the upstream-side reversing parallel shaft gear is located on the insertion side of the sheet storage container. A sheet storage device characterized in that, at the time the sheet storage container is pulled out from the sheet storage device body and the driven-side reversing parallel shaft gear separates from the drive-side reversing parallel shaft gear, the second rotation axis is located on the side of the sheet storage container pulling out direction relative to the second virtual vertical line.

4. A sheet storage device according to claim 1, A sheet storage device characterized in that the rotational trajectory of the outer circumference of the driven-side reversing parallel shaft gear is lower than the first rotation axis of the drive-side reversing parallel shaft gear when the sheet storage container is inserted into the sheet storage device body, and higher than the first rotation axis of the drive-side reversing parallel shaft gear at the time when the sheet storage container is withdrawn from the sheet storage device body and the driven-side reversing parallel shaft gear separates from the drive-side reversing parallel shaft gear.

5. A sheet storage device according to claim 1, A seat housing device characterized in that the outer diameter of the driven-side reversing parallel shaft gear is smaller than the outer diameter of the driving-side reversing parallel shaft gear.

6. A sheet storage device according to claim 3, The seat storage device is characterized in that the main body side driving force transmission mechanism rotatably supports the driving side reversing parallel shaft gear and the upstream side reversing parallel shaft gear while they are meshed together, and further includes a support member that is pivotable around a pivot axis coaxial with the upstream rotation axis of the upstream side reversing parallel shaft gear.

7. A sheet storage device according to claim 6, A sheet storage device characterized by having a restricting part that restricts the swinging of the support member around the pivot axis toward the pulling direction when the sheet storage container is pulled out from the sheet storage device body, by disengaging the drive-side reversing parallel shaft gear and the driven-side reversing parallel shaft gear.

8. A sheet storage device according to claim 7, The sheet storage device is characterized in that the restricting portion restricts the swing of the support member from a first swing position, which is the first angle, to a second swing position, which is the second angle, when the sheet storage container is pulled out from the sheet storage device body.

9. A sheet storage device according to claim 7, The sheet storage device is characterized in that the restricting portion allows the support member to swing from a first swing position at a first angle to a second swing position at a second angle when the sheet storage container is pulled out from the sheet storage device body, and includes a biasing member that biases the support member toward the insertion direction when the engagement between the drive-side reversing parallel shaft gear and the driven-side reversing parallel shaft gear is released, so that the support member returns to the first swing position and is maintained in the first swing position.

10. An image forming apparatus characterized by comprising a sheet storage device according to any one of claims 1 to 9.

Images