Sheet conveying device and image forming apparatus including the same

Abstract

The invention relates to a sheet conveying device and an image forming apparatus including the same. A sheet conveying apparatus includes a cassette storage unit, a sheet storage cassette, and a sheet conveying unit. The sheet storage cassette includes a cassette base portion that stores a sheet-like recording medium, and is pluggable with respect to a cassette storage portion. The sheet conveyance unit is provided in the cassette storage unit and conveys the recording medium stored in the sheet storage cassette. A pair of fixed side rails made of metal is installed on the box containing part. The cartridge base part is made of resin, and a pair of inner rails are integrally formed on the side surfaces of the cartridge base part, and the pair of inner rails and the pair of fixed side rails are connected in a slidable manner.

Description

Technical Field

[0001] The present invention relates to a sheet conveying device and an image forming apparatus equipped with the same. The sheet conveying device includes a sheet storage box in which a sheet-shaped recording medium is loaded and stored in a box base. Background Art

[0002] In image forming apparatuses such as copiers, printers, and facsimile machines, a sheet storage cassette capable of appropriately loading sheets (paper) of various sizes is provided so as to be insertable and removable with respect to a main body of the image forming apparatus.

[0003] The sheet storage box is installed in the box storage part of the image forming apparatus body so as to be inserted and pulled out by a slide rail having an outer rail provided on the image forming apparatus body side and an inner rail provided on the sheet storage box side.

[0004] Since sheet storage boxes are mostly made of resin, there are the following problems: the bottom of the box is bent due to the load of paper acting on the bottom of the box, and the side of the box tilts inward. When the side of the box tilts inward, the position accuracy between the sheet storage box and the slide rail is reduced, and the sheet storage box inserted into the main body of the image forming device cannot be reliably positioned, so there is a possibility of paper feeding failures such as skewing (skewed) and non-feeding of paper. In recent years, in order to accommodate large-sized paper exceeding A3 size, the sheet storage box itself has been enlarged. Therefore, the weight of the paper that can be stored in the sheet storage box is also heavier, and the tilting of the side of the box is more significant. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] An object of the present invention is to provide a sheet conveying device and an image forming apparatus, which can improve the strength of a cassette side surface with a simple structure, thereby reliably positioning a sheet storage cassette in a cassette storage portion.

[0007] (II) Technical solution

[0008] Regarding the first structure of the sheet conveying device of the present invention, it is characterized in that it comprises: a box storage portion; a sheet storage box, which has a box base for storing sheet-shaped recording media and is pluggable relative to the box storage portion; and a sheet conveying portion, which is arranged in the box storage portion and conveys the recording medium stored in the sheet storage box, and a pair of metal fixed side rails are installed in the box storage portion, the box base is made of resin, and a pair of inner rails are integrally formed on the side of the box base, and the pair of inner rails are slidably connected to the pair of fixed side rails.

[0009] Furthermore, the present invention is an image forming apparatus including: a sheet conveying device having the above-described structure; and an image forming unit for forming an image on a recording medium conveyed by the sheet conveying device.

[0010] (III) Beneficial effects

[0011] According to the first structure of the present invention, an inner track is integrally formed on the side of the box base to improve the strength of the side, thereby preventing the side from tipping inward. Therefore, the strength of the side can be ensured without using auxiliary components, and the positioning accuracy of the side can be improved. In addition, the positional relationship between the recording medium stored in the box base and the sheet conveying part on the box storage part side is stabilized, thereby preventing the occurrence of recording medium conveying failures.

[0012] Furthermore, according to the second configuration of the present invention, an image forming apparatus is obtained in which a recording medium conveyance failure is unlikely to occur. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic cross-sectional view showing the internal structure of an image forming apparatus 100 including a sheet conveying device 120 according to an embodiment of the present invention.

[0014] Figure 2 This is a perspective view of the appearance of the paper feeding cassette 1a as seen from above.

[0015] Figure 3 This is a partial perspective view of the inner side surface of the cassette housing portion 101 on the downstream side in the paper feeding direction as viewed from the cassette insertion direction.

[0016] Figure 4 This is a perspective view of the vicinity of the end portion 41d on the downstream side in the insertion direction of the inner rail 41 as viewed from the upstream side in the insertion direction.

[0017] Figure 5 This is a perspective view of the vicinity of the end portion 41 d on the downstream side in the insertion direction of the inner rail 41 as viewed from the downstream side in the insertion direction.

[0018] Figure 6 It is a cross-sectional view showing a state in which the inner rail 41 of the paper feeding cassette 1 a is engaged with the outer rail 42 and the middle rail 43 of the cassette storage portion 101 . DETAILED DESCRIPTION

[0019] Embodiments of the present invention will be described below with reference to the accompanying drawings. Figure 1 1 is a side cross-sectional view showing the internal structure of the image forming apparatus 100 including the sheet conveying device 120 according to one embodiment of the present invention. In addition, the solid arrows in the figure indicate the conveying path of the paper P and the conveying direction.

[0020] exist Figure 1In the image forming apparatus 100, a cassette storage unit 101 is arranged at the lower part. The cassette storage unit 101 is provided with two paper feed cassettes 1a and 1b. Bundles of paper P such as cut paper before printing are loaded and stored inside the paper feed cassettes 1a and 1b, and the paper feed units 117a and 117b provided in the main body of the image forming apparatus 100 separate the paper P from the bundle of paper P one by one and feed them out. The cassette storage unit 101, the paper feed cassettes 1a and 1b, and the paper feed units 117a and 117b constitute a sheet conveying device 120.

[0021] The paper feeding unit 117a includes a pickup roller 29a provided corresponding to the paper feeding cassette 1a, a feed roller 30a, and a retard roller 31a pressed against the feed roller 30a. The paper feeding unit 117b includes a pickup roller 29b provided corresponding to the paper feeding cassette 1b, a feed roller 30b, and a retard roller 31b pressed against the feed roller 30b.

[0022] A manual paper feeder 102 is provided outside the upper right side of the image forming apparatus 100. The manual paper feeder 102 can be loaded with paper of a size or thickness different from that of the cassette storage unit 101, or sheets fed one by one such as OHP sheets, envelopes, postcards, and forms.

[0023] A paper conveying unit 103 is disposed in the image forming apparatus 100. The paper conveying unit 103 is located on the downstream side in the paper feeding direction, i.e., on the right side, with respect to the cassette storage unit 101, and is located on the downstream side in the paper feeding direction, i.e., on the left side, with respect to the manual paper feeding unit 102. The paper P fed from the cassette storage unit 101 is conveyed vertically upward along the side surface of the main body of the image forming apparatus 100 by the paper conveying unit 103, and the paper P fed from the manual paper feeding unit 102 is conveyed horizontally.

[0024] A document conveying device 104 is disposed on the upper surface of the image forming apparatus 100, and an image reading unit 105 is disposed below the document conveying device 104. When copying a document, a plurality of documents are loaded on the document conveying device 104. The document conveying device 104 separates and conveys the documents one by one, and the image reading unit 105 reads image data of the document.

[0025] An image forming section 106 and a transfer section 107 are arranged on the downstream side of the paper conveying direction of the paper conveying section 103 and below the image reading section 105. In the image forming section 106, an electrostatic latent image of the original image is formed based on the image data read by the image reading section 105, and the electrostatic latent image is developed to form a toner image. On the other hand, in synchronization with the formation timing of the toner image in the image forming section 106, the paper P is conveyed from the cassette storage section 101 to the transfer section 107 via the paper conveying section 103. The toner image formed in the image forming section 106 is transferred to the paper P in the transfer section 107.

[0026] A fixing section 108 is disposed downstream of the transfer section 107. The paper P to which the toner image is transferred in the transfer section 107 is conveyed to the fixing section 108, and passes through the nip portion of a fixing roller pair composed of a heating roller and a pressure roller, so that the toner image on the paper P is fixed to form a permanent image. The paper P discharged from the fixing section 108 is discharged to a paper discharge tray 111, which is provided on the outer side of the left side surface of the image forming apparatus 100.

[0027] Next, a specific structure of the paper feed cassette 1 a detachably attachable to the image forming apparatus 100 will be described. Figure 2 This is a perspective view of the appearance of the paper feed box 1a as viewed from the upper front surface side. In addition, although the structure of the paper feed box 1a is described here, the structure of the paper feed box 1b is exactly the same. Figure 2 In FIG. 1 , an arrow A indicates an insertion direction of the paper feeding cassette 1 a into the cassette housing portion 101 , an arrow A′ indicates a pull-out direction, and an arrow B indicates a paper feeding direction of paper from the paper feeding cassette 1 a .

[0028] The paper feed cassette 1a is stored in Figure 1 The cassette storage section 101 of the image forming apparatus 100 shown in FIG. The main body of the paper feed cassette 1a, that is, the cassette base 10 is a flat box-shaped resin with an open top surface, and the paper P is loaded and stored from the top surface direction. In the cassette storage section 101 inside the image forming apparatus 100, a paper feed unit 117a (see FIG. 117 ) is provided above the paper feed cassette 1a. Figure 1 ), paper P (refer to Figure 1 ) Figure 2 The box cover 3 is installed on the side 10a of the front surface side of the box base 10. The surface side ( Figure 2 The left front side of the cassette cover 3 is exposed to the outside and constitutes a part of the outer surface of the main body of the image forming apparatus 100. The cassette cover 3 is provided with a gripping portion 3a for gripping when inserting and removing the paper feeding cassette 1a relative to the cassette storage portion 101.

[0029] An inner rail 41 is provided on the outer side of a pair of side surfaces 10b parallel to the insertion and removal direction (arrow AA' direction) of the box base 10. The inner rail 41 is made of resin and is formed integrally with the box base 10. The inner rail 41 is formed at a position closer to the lower end of the side surface 10b (the bottom surface of the box base 10) than the upper end (the opening of the box base 10) along the vertical direction of the side surface 10b.

[0030] The inner rail 41 is aligned with the middle rail 43 (see Figure 6 ) and move the paper feed box 1a along the Figure 2 The cartridge is horizontally slid in the direction of arrow A shown and inserted into the cartridge storage portion 101 .

[0031] Inside the box base 10, there are provided: a paper loading plate (not shown) for loading the paper P, a pair of width limit indicators 11a for positioning the paper P loaded on the paper loading plate in the width direction, and a rear end indicator 11b for aligning the rear end of the paper P loaded on the paper loading plate by being arranged at a position corresponding to the size of the paper P.

[0032] Since the paper P is directed toward the paper conveying unit 103 (refer to Figure 1 ) is fed in the direction of arrow B, so a pair of width limit indicators 11a for positioning the paper P in the width direction are provided so as to be reciprocable in a direction (arrow AA′ direction) orthogonal to the paper feeding direction along an indicator guide groove 12a formed in the box base 10. In addition, a rear end indicator 11b for aligning the rear end of the paper P is provided so as to be reciprocable in parallel with the paper feeding direction (arrow B direction) along an indicator guide groove 12b formed in the box base 10.

[0033] Figure 3 This is a partial perspective view of the inner side surface of the downstream side of the paper feeding direction of the cassette storage portion 101 as viewed from the cassette insertion direction. Figure 3 As shown, the paper feed units 117a and 117b are supported in a detachable manner on the cassette storage portion 101, and the cassette storage portion 101 is formed on a pair of side frames 100a and 100b (in the rear side and the front side of the image forming apparatus 100) arranged opposite to each other. Figure 3 , between the side frames 100b on the front side (not shown).

[0034] A deceleration contact and separation lever 60 is provided below the pickup rollers 29a and 29b. Since the paper feed cassettes 1a and 1b are installed in the cassette storage portion 101, the deceleration contact and separation lever 60 is pressed, allowing the deceleration rollers 31a and 31b (see Figure 1 ) moves toward the feed rollers 30a and 30b, causing the feed roller 30a to contact the retardation roller 31a and the feed roller 30b to contact the retardation roller 31b, respectively, to form a paper feed roller pair.

[0035] The outer rail 42 is fixed to the side frame 100a. The outer rail 42 has a main body 42a in the shape of a long and thin plate, and a pair of bent edges 42b formed by bending both side ends of the main body 42a in the longitudinal direction. The cross-sectional shape of the outer rail 42 in the direction perpendicular to the longitudinal direction is substantially C-shaped. The middle rail 43 (see FIG. 1 ) is inserted into the outer rail 42 in a slidable manner. Figure 6 The inner rail 41 is inserted into the middle rail 43 in a slidable manner (refer to Figure 2 ), the inner track 41 is formed on the side surface 10b of the box base 10.

[0036] Figure 4 and Figure 54 is a perspective view of the vicinity of the end portion 41d on the downstream side of the insertion direction of the inner rail 41 as viewed from the upstream side and the downstream side of the insertion direction. Figure 4 and Figure 5 , it is shown that on one side of the box base 10 ( Figure 2 The inner track 41 is formed on the side surface 10b of the box base 10 (the front side of the paper), but on the other side of the box base 10 ( Figure 2 The inner track 41 formed on the side 10b (on the depth side of the paper) also has exactly the same structure.

[0037] The inner rail 41 has: an elongated flat plate-shaped main body 41a extending in the insertion and removal direction of the paper feed cassette 1a; and a pair of guide ribs 41b protruding outward at both side ends of the main body 41a in the longitudinal direction. The cross-sectional shape of the inner rail 41 in the direction perpendicular to the longitudinal direction is similar to that of the outer rail 42 and the middle rail 43 (both refer to Figure 6 ) are roughly C-shaped with opposite directions.

[0038] In addition, an anti-drop component 50 is installed in the inner rail 41 (see Figure 2 The anti-slip component 50 prevents the inner rail 41 from being detached from the middle rail 43. The anti-slip component 50 is attached to the downstream side of the insertion direction of the center portion of the inner rail 41 in the longitudinal direction.

[0039] On the downstream side of the insertion direction of the anti-dropping member 50 ( Figure 4 ), a plurality of (six in this case) reinforcing ribs 41c extending in the vertical direction are formed between the guide ribs 41b. The reinforcing ribs 41c are formed to improve the strength of the inner rail 41.

[0040] The end 41d of the inner rail 41 on the downstream side in the insertion direction protrudes further toward the downstream side in the insertion direction than the side surface 10c on the downstream side in the insertion direction of the cassette base 10. Thus, when the paper feed cassette 1a is inserted into the cassette storage section 101, the end 41d of the inner rail 41 is aligned with the middle rail 43 on the cassette storage section 101 side (see Figure 6 ) It is easy to coordinate the position.

[0041] like Figure 5 As shown, a pair of inclined portions 45 are formed at the end portion 41d on the downstream side of the inner rail 41 in the insertion direction. The pair of inclined portions 45 are respectively formed on the pair of guide ribs 41b of the inner rail 41. More specifically, the upper guide rib 41b of the pair of guide ribs 41b is formed with an inclined portion 45 that is inclined downward toward the insertion direction. The lower guide rib 41b is formed with an inclined portion 45 that is inclined upward toward the insertion direction. That is, the pair of inclined portions 45 are respectively inclined toward the inner side of the width direction of the inner rail 41 as they move toward the downstream side in the insertion direction.

[0042] Figure 61 is a cross-sectional view showing a state where the inner rail 41 of the paper feed cassette 1a is engaged with the outer rail 42 and the middle rail 43 of the cassette storage section 101. A pair of outer rails 42 and a middle rail 43 are mounted on the cassette storage section 101 at positions opposite to the pair of inner rails 41 formed on the paper feed cassette 1a. The middle rail 43 is made of metal and has the same shape as the outer rail 41, and has a main body 43a and a pair of bent edges 43b formed by bending both end edges of the main body 43a in the longitudinal direction.

[0043] A first ball bearing 51 is disposed inside a pair of bent edges 42b of the outer rail 42. The first ball bearing 51 holds a plurality of balls rotatably at predetermined intervals along the length direction. The first ball bearing 51 faces the outer side of a pair of bent edges 43b of the middle rail 43. Since the balls of the first ball bearing 51 roll between the bent edges 42b and 43b, the middle rail 43 is held slidably on the outer rail 42.

[0044] A second ball bearing 52 is disposed inside a pair of bent edges 43b of the middle rail 43. The second ball bearing 52 holds a plurality of balls rotatably at predetermined intervals along the length direction. The second ball bearing 52 faces the outer side of a pair of guide ribs 41b of the inner rail 41. Since the balls of the second ball bearing 52 roll between the bent edges 43b and the guide ribs 41b, the inner rail 41 is held slidably on the middle rail 43.

[0045] By inserting the paper cassette 1a into the cassette housing 101, the inner rails 41 are inserted into the outer rails 42. When the paper cassette 1a is inserted to a predetermined position (paper feeding position) in the cassette housing 101, the inner rails 41 are completely accommodated in the middle rails 43, and the middle rails 43 are completely accommodated in the outer rails 42.

[0046] When the paper feeding cassette 1a is inserted into the paper feeding position, a pressing rib (not shown) provided on the side surface 10b of the cassette base 10 presses against a decelerating contact separation lever 60 (see FIG. 1 ) provided on the cassette storage portion 101. Figure 3 ) is pressed. When the deceleration contact separation lever 60 is pressed, the deceleration roller 31a (refer to Figure 1 ) is pushed up by the deceleration contact and separation mechanism (not shown) and abuts against the feed roller 30a.

[0047] When replenishing the paper P to the paper cassette 1a, the paper cassette 1a is pulled out from the cassette housing 101. When the paper cassette 1a is pulled out from the cassette housing 101 to a predetermined position (paper replenishment position), the inner rails 41 are completely pulled out from the middle rails 43 and the middle rails 43 are completely pulled out from the outer rails 42.

[0048] At this time, the anti-dropping member 50 (see Figure 2) is engaged with the engaging portion (not shown) of the middle rail 43, thereby preventing the inner rail 41 from falling off from the middle rail 43. In addition, the anti-falling component installed on the middle rail 43 is engaged with the engaging portion (not shown) of the outer rail 42, thereby preventing the middle rail 43 from falling off from the outer rail 42.

[0049] On the other hand, when the paper supply unit 117a in the box storage section 101 is removed for maintenance, or when a paper jam is handled in the box storage section 101, the engagement between the anti-slip component 50 and the middle rail 43 is released while the paper supply box 1a is pulled out to the maximum, the inner rail 41 is pulled out from the middle rail 43, and the paper supply box 1a is removed.

[0050] According to the structure of this embodiment, the inner rail 41 is integrally formed on the side 10b of the box base 10 to improve the strength of the side 10b, thereby preventing the side 10b from tipping inward. Therefore, the strength of the side 10b can be ensured without using auxiliary components, and the positioning accuracy of the side 10b can be improved. In addition, the positional relationship between the paper P stored in the box base 10 and the paper supply unit 117a on the box storage portion 101 side is stabilized, thereby preventing the occurrence of paper supply failure.

[0051] In addition, the positional accuracy of the pressing rib formed on the side surface 10 b is also improved, so when the paper feeding cassette 1 a is inserted into the paper feeding position, the deceleration contact separation lever 60 can be reliably pressed by the pressing rib.

[0052] In addition, the outer rail 42 and the middle rail 43 disposed on the cassette storage portion 101 side are made of metal, and the first ball bearing 51 and the second ball bearing 52 are provided on the outer rail 42 and the middle rail 43, respectively. Thus, the outer rail 42 and the middle rail 43 slide smoothly, and the middle rail 43 and the inner rail 41 slide smoothly. Therefore, compared with a structure in which a guide rib made of resin formed on the paper feed cassette 1a side and a guide rail made of resin formed on the cassette storage portion 101 side are engaged and slid, the paper feed cassette 1a can be smoothly inserted and pulled out.

[0053] In addition, a reinforcing rib 41c extending in the vertical direction is formed between the guide ribs 41b on the downstream side of the inner rail 41, more specifically, on the downstream side of the anti-slip member 50 with respect to the insertion direction, thereby ensuring the strength of the inner rail 41. This prevents the inner rail 41 from being deformed or damaged when the paper P is replenished to the cassette base 10 in a state where the paper feed cassette 1a is pulled out to the maximum extent.

[0054] In addition, by making the end 41d of the inner rail 41 on the downstream side in the insertion direction protrude further downstream in the insertion direction than the side surface 10c of the box base 10 on the downstream side in the insertion direction, the position matching of the end 41d of the inner rail 41 and the middle rail 43 is facilitated.

[0055] Furthermore, by forming a pair of inclined portions 45 at the end 41d on the downstream side in the insertion direction of the inner rail 41, the end 41d of the inner rail 41 can be easily inserted between the bent edges 43b of the middle rail 43. Therefore, the paper feed cassette 1a can be easily installed in the cassette storage unit 101.

[0056] In addition, the present invention is not limited to the above-mentioned embodiment, and various changes can be made without departing from the scope of the present invention. For example, in the above-mentioned embodiment, the inner rail 41 is formed at a position close to the bottom surface of the side surface 10b, but the inner rail 41 can also be formed at other positions of the side surface 10b. In addition, as long as the strength of the inner rail 41 can be ensured, the reinforcing rib 41c formed on the inner rail 41 can be formed at more than one place.

[0057] In the above embodiment, a slide rail composed of the inner rail 41, the outer rail 42, and the middle rail 43 and extending and retracting in three stages is used, but a slide rail composed of only the outer rail 42 and the inner rail 41 and extending and retracting in two stages may also be used.

[0058] The present invention can be used for a sheet storage box for loading and storing sheet-shaped recording media in a box base. By using the present invention, a sheet conveying device and an image forming device can be provided, which can improve the strength of the box side with a simple structure, so that the sheet storage box can be reliably positioned in the box storage part.

Claims

1. A sheet conveying device, comprising: Box storage unit; A sheet storage box having a box base for storing sheet-shaped recording media and being insertable and removable with respect to the box storage portion; and a sheet conveying unit, which is provided in the cassette storage unit and conveys the recording medium stored in the sheet storage cassette; The sheet material conveying device is characterized in that: A pair of metal fixed side rails are installed in the box storage portion. The case base is made of resin, and a pair of inner rails are integrally formed on the side of the case base. The pair of inner rails are slidably connected to the pair of fixed-side rails.

2. The sheet material conveying device according to claim 1, characterized in that: The fixed side track is composed of a pair of outer tracks and a pair of center tracks. The outer track is fixed to the inner side surface of the box storage portion. The middle rail is slidably connected to the outer rail. The pair of inner rails are slidably connected to the pair of outer rails via the pair of middle rails.

3. The sheet material conveying device according to claim 1, characterized in that: The inner rail has a flat plate-shaped main body and a pair of guide ribs. The main body extends in the insertion and removal direction of the sheet storage box. The guide ribs protrude outward at both side ends along the length direction of the main body. On the main body, one or more reinforcing ribs extending in a vertical direction are formed between the pair of guide ribs.

4. The sheet material conveying device according to claim 3, characterized in that: The inner rail has an anti-slip component, which is arranged on the main body to prevent the inner rail from detaching from the fixed side rail. The reinforcing rib is formed on a downstream side of the anti-slip member with respect to an insertion direction of the sheet storage box.

5. The sheet material conveying device according to claim 1, characterized in that: With respect to the insertion direction of the sheet storage case, an end portion of the inner rail on the downstream side protrudes further toward the downstream side in the insertion direction than a side surface of the case base on the downstream side in the insertion direction.

6. The sheet material conveying device according to claim 1, characterized in that: The inner rail is formed at a position of the side surface closer to a lower end portion than to an upper end portion.

7. The sheet material conveying device according to claim 1, characterized in that: The sheet conveying unit comprises: a feed roller for conveying the recording medium stored in the sheet storage box; A deceleration roller capable of contacting and separating relative to the feed roller; as well as a deceleration contact and separation lever, which makes the deceleration roller contact or separate with respect to the feed roller, The deceleration contact and separation lever is pressed in a state where the sheet storage cassette is inserted into the cassette storage portion.

8. An image forming apparatus comprising: The sheet conveying device and the image forming unit according to any one of claims 1 to 7, The image forming section forms an image on a recording medium conveyed by the sheet conveying device.

Images