JP4888060B2 - Feeding department - Google Patents

Description

  The present invention relates to a feeding unit.

  The image forming apparatus includes a feeding unit that feeds a sheet-like recording medium for forming an image to the image forming unit. The feeding unit includes a recording medium storage unit that stacks and stores sheet-like recording media and is detachably mounted on the mounting unit of the apparatus main body. Then, in this recording medium accommodating portion, a bottom plate (bottom plate) on which sheet-like recording media are stacked is raised by an elastic member, and the bottom plate is pushed up so as to come into contact with the sheet conveying member that feeds the recording medium at a substantially constant pressure. The method is generally adopted.

  In such a bottom plate push-up system, when the recording medium accommodating portion is attached to the attachment portion, the bottom plate can be freely raised according to the amount of the recording medium loaded on the bottom plate. Further, when pulling out or inserting the recording medium accommodating portion, the bottom plate is lowered to prevent interference with the sheet conveying means, and when the user replenishes or supplies the recording medium by pulling out the recording medium accommodating portion. In order to supply a recording medium without being affected by an elastic member or the like, the bottom plate is maintained in a lowered state.

Specifically, both ends of the bottom plate are pushed down, and the engaging portion provided at the center of the bottom plate is engaged with the engaged portion of the recording medium accommodating portion, thereby maintaining the bottom plate in a lowered state ( For example, see Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4.)
JP 05-058476 A JP 2004-043189 A Japanese Patent Laid-Open No. 2002-347954 JP 2001-253567 A

  However, in such a configuration, when both ends of the bottom plate are pushed down, the bottom plate is bent or twisted, so that the central portion floats with respect to both ends. For this reason, the engaging part in the center part of the bottom plate does not sufficiently lower and does not engage with the engaged part. Therefore, it is necessary to increase the strength of the bottom plate or increase the stroke.

  The present invention has been made to solve the above problem, and an object of the present invention is to more reliably engage an engaging portion provided on a bottom plate of a recording medium accommodating portion with an engaged portion.

In order to achieve the above object, the feeding unit according to claim 1 accommodates a sheet-like recording medium, a recording medium accommodating unit that is detachably mounted on a mounting unit of the apparatus main body, and the recording medium accommodating The bottom plate is provided so as to be able to swing and is held by the elastic member, and the bottom plate is provided at both ends of the bottom plate in the width direction perpendicular to the feeding direction of the recording medium and is pushed down. and the bottom plate is pressed portion which is pressed down against the elastic force of the elastic member by, provided in the press section, while being operated to push down the bottom plate, the projecting the mounting portion above the said bottom plate An operation unit that abuts on a contact portion provided on the mounting portion and pushes down the pressing portion when the recording medium accommodating portion is inserted, and is provided at a lower portion of the pressing portion, and the pressing portion is pressed down. Thus, an engaging portion that engages with the engaged portion provided in the recording medium accommodating portion, provided in the pressing portion protrudes outward in the width direction than the operating portion, provided in the recording medium housing portion And a support portion that moves along the guide portion .

  In the feeding unit according to claim 1, an operation unit that is operated when the bottom plate is pushed down, and an engagement unit that is pushed down together with the operation unit and engages with an engaged part provided in the recording medium housing unit. The pressing part comprised integrally is provided.

  Therefore, when the operating portion is pushed down, for example, the engaging portion is lowered without the bottom plate being affected by bending or the like. That is, the pressing amount (moving amount) of the operation unit is the moving amount of the engaging unit. Therefore, the engaging portion is reliably engaged with the engaged portion without increasing the stroke. Further, it is not necessary to increase the strength of the bottom plate by increasing the thickness of the bottom plate to prevent bending.

Further, the pressing portions are provided at both end portions in the width direction orthogonal to the feeding direction of the recording medium on the bottom plate. Therefore, the posture of the bottom plate after the engagement is stabilized.

Moreover, since the operation part protrudes upwards from a bottom plate, it is easy to push down. Moreover, it can reduce in size in the width direction.

According to a second aspect of the present invention , in the configuration according to the first aspect , the contact start position where the operation portion of the pressing portion contacts the contact portion is closer to the insertion direction than the support portion. It is characterized by being.

In the feeding unit according to the second aspect, the contact start position at which the operation unit contacts the contact unit is located on the insertion direction side with respect to the support unit. Therefore, when the recording medium accommodating portion is inserted into the mounting portion, the pressing start can be made earlier. Therefore, in the insertion process of the recording medium accommodating portion, the operation portion is pushed down faster than the conventional method of pushing down the supporting portion. That is, the bottom plate is pushed down more quickly. Therefore, for example, it is possible to prevent problems such as the recording medium on the bottom plate being caught by the mounting portion. Moreover, since the inclination of the contact portion can be made gentler than the conventional method of pushing down the support portion, the insertion resistance can be reduced.

  Further, since it is not necessary to dispose the contact portion in the width direction from the recording medium housing portion, the size can be reduced in the width direction.

According to a third aspect of the present invention, in the configuration according to the first or second aspect , the engaged portion moves in a substantially horizontal direction and engages with the engaging portion. .

In the feeding portion according to the third aspect , the engaged portion moves in a substantially horizontal direction and engages with the engaging portion, so that the size can be reduced in the vertical direction.

According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, when the recording medium storage unit is mounted on the mounting unit, the engaged unit is The recording medium accommodating portion is positioned in the mounting direction by engaging with a step portion provided in the mounting portion.

In the feeding unit according to the fourth aspect , since the engaged portion is engaged with the stepped portion provided in the mounting portion and the recording medium accommodating portion is positioned in the mounting direction, it is different from the engaged portion. The positioning member is not required (the engaged portion also serves as the positioning member). Therefore, the number of parts is small.

  As described above, according to the present invention, the engaging portion provided on the bottom plate of the recording medium accommodating portion is securely engaged by the engaged portion.

  Hereinafter, an image forming apparatus including a feeding unit according to an exemplary embodiment of the present invention will be described with reference to the drawings.

  An image forming apparatus 10 shown in FIG. 1 forms an image on a recording sheet P (see FIG. 2) as a sheet-like recording medium based on image information input from an external apparatus.

  A paper feed cassette 20 serving as a recording medium storage unit is disposed in the mounting unit 50 at the lower part of the apparatus main body 12.

  As shown in FIGS. 1 and 2, the paper feed cassette 20 is inserted and removed in the insertion / removal direction (arrow S direction) from the attachment port 18 of the attachment unit 50 formed on the front surface of the apparatus body 12. It is supposed to be removable.

  In the present embodiment, the paper feed cassette 20 and the mounting unit 50 correspond to the feeding unit described in the claims.

  Further, along the arrow S in FIG. 1, the left front side is the apparatus front side (front side), and the right back side is the apparatus back side.

  As shown in FIG. 3, the paper feed cassette 20 is formed in a box shape and includes a cassette body 22 that accommodates recording paper P (see FIG. 2). The cassette body 22 includes a rectangular bottom surface 24 and a frame wall 25 that forms an outer frame along the outer periphery of the bottom surface 24. A bottom plate 26 is provided on the bottom surface 24 of the cassette body 22 and is lifted in the upward direction by the elastic force of springs 60 and 62 (see FIG. 5) as elastic members. P (see FIG. 2) is loaded. Details of the bottom plate 26 will be described later.

  Then, the recording paper P accommodated in the paper feed cassette 20 is sent out in the feeding direction (arrow T direction) by a sheet conveying means (not shown). The recording paper P delivered from the paper feed cassette 20 is conveyed to an image forming section (not shown) in the image forming apparatus 10 shown in FIG. Discharged.

  The image forming method of the image forming unit of the image forming apparatus 10 may be any method. For example, an electrophotographic system or an inkjet system may be used. Alternatively, a thermal transfer method or an impact dot method may be used.

  Further, the sheet-like recording medium is not limited to the recording paper P. Any sheet-like recording medium capable of forming an image may be used. For example, an OHP sheet may be used.

  Now, as shown in FIG. 3, frame walls 25 </ b> A arranged on both sides in the width direction (arrow W direction) orthogonal to the feeding direction (arrow T direction) of the recording paper P in the cassette body 22 of the paper feed cassette 20. , B are provided with two side guide portions 30A, 30B. These side guide portions 30A and 30B are positioned in the width direction of the recording paper P by hitting the end of the recording paper P (see FIG. 2) accommodated in the cassette body 22 in the width direction.

  The side guide portions 30A and 30B have a substantially rectangular plate shape, and are arranged so that the plate surfaces are substantially parallel to the frame walls 25A and 25B on both sides. Slide portions 32A and 32B extending in a direction away from the frame walls 25 on both sides (inward direction in the width direction W) are formed below the side guide portions 30A and 30B. And these slide parts 32A and 32B are arrange | positioned so that it may rank in parallel mutually. In addition, rack teeth H are formed on the sides facing each other in the slide portions 32A and 32B.

  A pinion 34 that can mesh with the rack teeth H of the slide portions 32A and 32B is rotatably attached to the center portion of the bottom surface 24 in the width direction (arrow W direction). Accordingly, in conjunction with the movement of one side guide portion 30A (or 30B), the other side guide portion 30B (or 30A) maintains the same distance from the center of the pinion 34 while maintaining the width direction (arrow W direction). Move to.

  The bottom plate 26 is substantially H-shaped in plan view, with the fulcrum 05 (see FIG. 4) on the back side of the apparatus as a fulcrum fulcrum (hereinafter referred to as “the tip 26F of the bottom plate 26”). Can be moved up and down. Further, it is constantly urged upward by springs 60 and 62 (see FIG. 5).

  As shown in FIG. 5, pressing portions 100 </ b> A and 100 </ b> B are provided at both ends in the width direction of the front end portion 26 </ b> F of the bottom plate 26.

  In the following, A is appended after the reference (100) like the pressing part 100A, and B is attached after the reference (100) like the other pressing part 100B. In addition, various members and the like corresponding to one pressing part 100A are denoted by A, and various members and the like corresponding to the other pressing part 100B are denoted by B after the code. Furthermore, only one (or the other) may be illustrated and described, and the other (or one) may be omitted or described. Alternatively, when there is no need to distinguish between one and the other, A and B may be omitted for explanation.

  As shown in FIG. 6, the pressing portion 100 includes a guide pin 102 that protrudes outward in the width direction.

  These guide pins 102 are formed on the frame walls 25 </ b> A and 25 </ b> B on both sides in the width direction of the cassette body 22, protrude from the long holes 27 whose longitudinal direction is the vertical direction, and move along the long holes 27.

  Further, the pressing unit 100 is provided with an operation unit 104 that protrudes upward. When viewed in the width direction, the operation unit 104 has a triangular plate shape with the top as a vertex. Note that the apex portion 105 of the operation portion 104 is located on the back side of the apparatus with respect to the guide pin 102 (see FIGS. 4 and 11).

  Further, the pressing portion 100 is provided with a hook portion 106 that protrudes downward. The hook portion 106 can be engaged with a latch portion 150 provided in the cassette body 22.

  Then, as shown in FIGS. 6, 7, and 8, the guide pin 102 moves along the long hole 27 (see FIGS. 4 and 11) by pressing the operation unit 104 of the pressing unit 100 downward. At the same time, the bottom plate 26 is lowered. Furthermore, the hook portion 106 engages with the latch portion 150 by moving the hook portion 106 downward together with the operation portion 104. By engaging the hook portion 106 with the latch portion 150, the bottom plate 26 can be maintained in the lowered state.

  In the present embodiment, the operation unit 104 and the hook unit 106 are integrally formed. However, it does not necessarily have to be integrally molded. After the operation portion and the hook portion are formed as separate members, the operation portion and the hook portion may be integrated by joining (bonding, screwing, press-fitting, etc.).

  In FIG. 6, the latch portion 150 is urged outward in the width direction (horizontal direction) by a spring 152 (see also FIG. 5). Then, when the inclined portion 107 at the tip of the hook portion 106 comes into contact, the latch portion 150 moves and engages in the width direction.

  Further, as shown in FIGS. 4 and 5, the end portion 154 on the outer side in the width direction of the latch portion 150 protrudes outward from the frame walls 25 </ b> A and 25 </ b> B of the cassette body 22. Then, after the hook portion 106 is engaged with the latch portion 150, when the end portion 154 of the latch portion 150 is pushed inward in the width direction, the engagement is released.

  As shown in FIG. 11, the contact part 300 with which the operation part 104 of the pressing part 100 comes into contact hangs down from the upper part of the mounting part 50. When viewed in the width direction, the contact portion 300 has a trapezoidal shape in which the lower base is shorter than the upper base.

  Next, the operation of the bottom plate 26 when the paper feed cassette 20 is inserted into the mounting portion 50 with the bottom plate 26 raised will be described.

  As shown in FIG. 12A, the paper feed cassette 20 is inserted from the mounting opening 18 (see FIG. 2) of the mounting portion 50. The operation unit 104 of the pressing unit 100 contacts the inclined surface 302 of the contact unit 300.

  As shown in FIG. 12B, when the paper feeding cassette 20 is further inserted, the apex portion 105 of the operation unit 104 of the pressing unit 100 is pushed down along the inclined surface 302 of the contact unit 300. At the same time, the bottom plate 26 and the hook portion 106 are lowered.

  As shown in FIG. 12C, when the sheet feeding cassette 20 is further inserted, the operation unit 104 of the pressing unit 100 is further pressed down, the hook unit 106 is engaged with the latch unit 150, and the bottom plate 26. Is kept in a lowered state. Therefore, when the paper feed cassette 20 is mounted on the mounting portion 50, interference between the recording paper P and the transport member is prevented.

  It should be noted that in advance (before the paper feed cassette 20 is inserted into the mounting unit 50), the user depresses the operation unit 104 of the pressing unit 100 to engage the hook unit 106 with the latch unit 150, and the bottom plate 26 is lowered. The paper cassette 20 may be inserted into the mounting unit 50 after the state has been reached.

  As shown in FIG. 12D, when the paper feeding cassette 20 is further inserted, the paper cassette 20 hits the convex portion 55 (see FIG. 9) protruding from the side wall in the width direction of the mounting portion 50, thereby causing the width direction. Pushed inward to disengage.

  Then, as shown in FIG. 10, the latch portion 150 is applied to the step portion 56 provided on the back side of the device of the convex portion 55 shown in FIG. 9 by the urging force of the spring 152 (see FIGS. 6, 7, etc.). By engaging the end 154 in the width direction, positioning in the mounting direction (arrow S direction) of the sheet feeding cassette 20 is performed.

  Next, the operation of this embodiment will be described.

  A pressing unit integrally configured with an operation unit 104 that is operated when the bottom plate 26 is pushed down and a hook unit 106 that is pushed down together with the operation unit 104 and engages a latch unit 150 provided in the sheet feeding cassette 20. 100.

  Therefore, when the operation unit 104 is pushed down, the hook unit 106 is lowered without being affected by, for example, the bending of the bottom plate 26. That is, the pressing amount (movement amount) of the operation unit 104 becomes the movement amount of the hook unit 106. Therefore, the hook portion 106 is reliably engaged with the latch portion 150 without increasing the stroke. Further, it is not necessary to increase the strength of the bottom plate 26 more than necessary by increasing the thickness of the bottom plate 26 to prevent bending.

  Further, the pressing portions 100 are provided at both end portions in the width direction of the bottom plate 26. Therefore, the posture of the bottom plate 26 after the engagement is stabilized.

  Further, as described with reference to FIGS. 12A to 12C, the contact start position where the operation unit 104 contacts the contact unit 300 is closer to the insertion direction than the guide pin 102 (on the right side in FIG. 12). )It is in. Therefore, when the paper feed cassette 20 is inserted into the mounting portion 50, the pressing start can be accelerated. Therefore, in the process of inserting the paper feed cassette 20, the operation unit 104, that is, the bottom plate 26 is pushed down quickly. Therefore, it is possible to prevent problems such as the recording paper P on the bottom plate 26 being caught by the mounting opening 18 (see FIG. 2) of the mounting portion 50.

  This will be described below by comparing with a conventional configuration.

  As shown in FIG. 13, the guide pin 902 provided at the end in the width direction of the bottom plate 926 moves along the long hole 927. In addition, when the guide pin 902 comes into contact with the contact portion 900 and is pressed down, the hook portion 906 provided at the center in the width direction of the bottom plate 926 is lowered, and the hook portion 906 is engaged with the latch portion 950. To do.

  FIG. 14 is a continuous view corresponding to FIG. 12 and showing the operation of the bottom plate 926 when the paper feed cassette 920 is inserted into the mounting portion 950 with the bottom plate 926 raised.

  As can be seen from a comparison between FIGS. 12A and 12B and FIGS. 14A and 14B, when the paper feed cassettes 20 and 920 are inserted into the mounting portions 50 and 950, the pressing start is performed in this embodiment. You can see that is faster.

  Therefore, as shown in FIGS. 12C and 14C, the inclined surface 302 of the contact portion 300 is used to engage the hook portions 106 and 906 with the latch portions 150 and 950 at substantially the same insertion position. The inclination of the inclined surface 932 of the contact portion 900 must be tighter than the inclination of (the inclined surface 932 is closer to the vertical). Therefore, the insertion resistance of the paper feed cassette 20 is smaller in this embodiment. Also, the push-down operation is smooth.

  Further, since the guide pin 902 protrudes in the width direction from the paper feed cassette 920, it is necessary to dispose the contact portion 900 in the width direction from the paper feed cassette 920. On the other hand, in the present embodiment, the operation unit 104 protrudes upward from the bottom plate 26 and does not stick out in the width direction, so that the contact part 300 also does not stick out in the width direction from the sheet feeding cassette 20. Therefore, the present embodiment can be downsized in the width direction.

  Further, since the latch portion 150 moves in a substantially horizontal direction (width direction) and engages with the hook portion 106, it can be downsized in the vertical direction.

  Furthermore, as shown in FIG. 10, the latch unit 150 also serves as a positioning member in the mounting direction of the paper feed cassette 20, so the number of parts is reduced.

  In addition, this invention is not limited to the said embodiment. For example, a configuration in which a pressing portion in which the operation portion and the hook portion are integrated may be provided in the side guide portions 30A and 30B.

1 is a perspective view illustrating an image forming apparatus including a feeding unit according to the present invention. FIG. 3 is a perspective view illustrating the image forming apparatus in a state where a paper feed cassette is pulled out. It is a perspective view which shows a paper feed cassette. It is a perspective view which shows the principal part of a paper feed cassette. It is a front view which shows typically the feeding part of this invention. It is a front view of the feeding part of the present invention which shows the state where the bottom plate rose. FIG. 7 is a schematic diagram of a feeding unit according to the present invention in which a pressing part is pushed from the state of FIG. 6 to engage a hook part and a latch part and a bottom plate is maintained in a lowered state. It is a side view of the state which the hook part and latch part of the pressing part engaged. The convex part and level | step-difference part of a mounting part are shown typically, (A) is a perspective view, (B) is a top view. It is a perspective view in the state where the end of the latch portion was engaged with the stepped portion and positioned. It is a side view which shows typically the feeding part of this invention. It is explanatory drawing which shows operation | movement of the bottom plate at the time of inserting a paper feeding cassette in a mounting part in the state which the bottom plate of the feeding part of this invention raised in order from (A) to (D). It is a side view which shows the conventional feeding part typically. It is explanatory drawing which shows operation | movement of the bottom plate at the time of inserting a paper feeding cassette in a mounting part in the state which the bottom plate of the conventional feeding part raised, in order from (A) to (D).

Explanation of symbols

20 Paper cassette (recording medium storage)
26 Bottom plate
27 Long hole (guide part)
50 Mounting part 56 Step part 60 Spring (elastic member)
62 Spring (elastic member)
100 Pressing part 102 Guide pin (supporting part)
104 Operation part 106 Hook part (engagement part)
150 Latch part (engaged part)
300 Contact portion P Recording paper (recording medium)

Claims (4)

A recording medium storage unit for storing a sheet-like recording medium and detachably mounted on the mounting unit of the apparatus main body;
A bottom plate that is slidably provided in the recording medium container, and can lift the accommodated recording medium by the elastic force of an elastic member;
A pressing portion provided at both ends of the bottom plate in the width direction orthogonal to the feeding direction of the recording medium, and the pressing down the pressing down the bottom plate against the elastic force of the elastic member ;
An abutting portion provided at the pressing portion and operated when the bottom plate is pushed down , and protruding above the bottom plate and provided at the mounting portion when the recording medium accommodating portion is inserted into the mounting portion. An operation unit that abuts against and depresses the pressing unit;
An engaging portion that is provided at a lower portion of the pressing portion and engages with an engaged portion provided in the recording medium housing portion by the pressing portion being pressed down ;
A support portion provided in the pressing portion, protruding outward in the width direction from the operation portion, and moving along a guide portion provided in the recording medium housing portion;
A feeding unit comprising: 2. The feeding unit according to claim 1 , wherein a contact start position where the operation unit of the pressing unit contacts the contact unit is located closer to the insertion direction than the support unit. The feeding unit according to claim 1, wherein the engaged portion moves in a substantially horizontal direction and engages with the engaging portion. When the recording medium accommodating portion is attached to the attachment portion, the engaged portion is engaged with a step portion provided in the attachment portion,
The feeding unit according to any one of claims 1 to 3, wherein the recording medium accommodating unit is positioned in a mounting direction .

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