JP3571818B2 - Sheet feeding device and image forming device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a sheet feeding device mounted on an image forming apparatus such as an electrophotographic copying machine, a laser beam printer, and a facsimile, and more specifically, a sheet loaded on a sheet loading unit is brought into contact with or separated from a feeding unit. The present invention relates to a sheet feeding device for feeding a sheet and an image forming apparatus using the sheet feeding device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a sheet feeding device used in an image forming apparatus such as an electrophotographic copying machine and a laser beam printer, as described in Japanese Utility Model Application Laid-Open No. 62-157726, the sheet feeding device is detachably attached to the apparatus main body. Paper cassette is used. The sheet cassette is configured such that a bottom plate (sheet stacking table), which is swingably provided on a bottom plate portion, is swung upward to push up the sheets stacked on the upper surface thereof and press the sheets against a sheet feeding roller. Have been.
[0003]
A lock member for attaching and detaching the cassette is provided on a handle portion of the sheet cassette, and a swing member provided on a cassette receiving stand on the apparatus main body side through a protrusion of the lock member for attaching and detaching the cassette. It is configured to control the operation. In addition, a tongue (tongue) for pushing up the sheet stacking table and a separating member for separating the sheet by contacting the sheet feeding roller are provided, and an interlocking member for interlocking these with the cassette swinging member is provided. The swinging member is operated through the intermediary member so as to press or release the pressing to the sheet feeding roller.
[0004]
Further, in order to adjust the sheet position (lateral registration) in the direction orthogonal to the sheet conveying direction, the apparatus main body is configured so that the receiving portion of the handle of the cassette can be movably adjusted in the direction orthogonal to the sheet conveying direction. The lateral registration is adjusted by shifting the relative position between the main body and the cassette.
[0005]
[Problems to be solved by the invention]
However, when the paper cassette is pulled out of the apparatus main body, there is a possibility that the separation member is kept pressed against the upper surface of the sheet at the beginning of the movement of the cassette, or if the lateral registration of the cassette is adjusted, the separation member is not moved. The timing of releasing the pressing of the sheet changes, so that the pressing of the sheet may not be completely released when the cassette moves, and the sheet may remain in the apparatus when the cassette is pulled out, or the front end of the sheet may be wrinkled after the drawing. was there.
[0006]
SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to prevent a sheet from remaining in the apparatus and wrinkling at a sheet leading end when the sheet is pulled out from the sheet storage means and the apparatus body. The present invention is to provide a sheet feeding device and the like capable of performing such operations.
[0007]
[Means for Solving the Problems]
A typical configuration according to the present invention for achieving the above object is a sheet feeding device in which a sheet storage unit in which sheets are stacked and stored is attached to an apparatus main body and fed by a feeding unit on the apparatus main body side. A sheet stacking unit for stacking and swinging sheets mounted on the sheet storage unit, a separation unit for separating a sheet disposed opposite to the feeding unit, and an apparatus attached to the sheet storage unit; A handle having a locking portion that can be locked or released from the main body, and by operating the handle, the sheet stacking unit and the separating unit are brought into contact with or separated from the feeding unit. And a pressurizing unit for moving the handle, wherein a position where the handle is attached to the sheet storage unit is configured to be slidable in a direction orthogonal to a sheet feeding direction.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of a sheet feeding apparatus according to the present invention and an image forming apparatus using the same will be specifically described with reference to FIGS. 1 to 5 are explanatory diagrams of the configuration of a sheet feeding device, and FIG. 6 is a schematic diagram of a copying machine as an image forming apparatus having the sheet feeding device.
[0009]
Here, the overall configuration of the copying machine will be described first with reference to FIG. 6, and then the configuration of the sheet feeding apparatus will be described with reference to FIGS.
[0010]
(Overall configuration of copier)
In FIG. 6, reference numeral 1 denotes a copying machine main body, which has a reader unit as an image reading unit at the top of the apparatus and an image printer unit as an image forming unit at the bottom of the apparatus. An original table 2 made of a transparent glass plate or the like is provided on the upper surface side of the copying machine body 1. An original O is placed on the original table 2 with the image surface facing downward, and is pressed and fixed by an original cover 3 that is openably and closably mounted near the original table 2.
[0011]
A document O placed on the document table 2 is irradiated with light by a lamp 4 and its light image is formed by a scanning optical system constituted by reflection mirrors 5, 6, 7, 8, 9, 10 and an imaging lens 11. Thereby, an image is formed on the photosensitive drum 12 as an image carrier. The lamp 4 and the reflection mirrors 5, 6, and 7 move at a predetermined speed in the direction of arrow a in FIG.
[0012]
The photosensitive drum 12 is driven to rotate at a predetermined speed in a direction indicated by an arrow in FIG. 6, and is uniformly charged on the drum surface by a primary charger 13. Then, the original image is exposed by the scanning optical system to form an electrostatic latent image. It is formed. Next, toner is supplied by the developing device 14, and the latent image is visualized.
[0013]
On the other hand, the sheets P are stacked and housed in a sheet cassette 15 as a sheet storage means, and the sheet cassette 15 is attached to the lower part of the copying machine main body 1 so as to be able to be pulled out to the near side in FIG. The sheets P stacked and accommodated in the sheet cassette 15 are separated and fed one by one by a pickup roller 16 as a feeding means, and are conveyed by a pair of slip rollers 17 to be nipped by a pair of registration rollers 18 stopped driving. Enter the department.
[0014]
The registration roller pair 18 starts rotating at a timing so that the toner image formed on the photosensitive drum 12 and the leading end of the sheet P coincide with each other, and transfers the sheet P to the surface of the photosensitive drum 12 via a transfer guide (not shown). Send in. The toner image is transferred to the sheet P by applying a voltage having a polarity opposite to that of the toner image by the transfer charger 19, and then the sheet P is separated from the drum surface by the separation charger 20. It is sent to 22. When the sheet P passes through the fixing device 22, heat and pressure are applied, and a transferred image is permanently fixed. Then, the sheet P is conveyed by a pair of discharge rollers 24 via a pair of fixing discharge rollers 23, and is discharged onto a discharge tray 25 provided outside the apparatus. Note that the toner remaining on the drum surface after the image transfer is removed by the cleaning device 26 to prepare for the next image formation.
[0015]
(Configuration of sheet feeding device)
Next, the configuration of the sheet feeding device will be specifically described with reference to FIGS. The sheet cassette 15 is mounted on the lower part of the copying machine main body 1 as described above. In the present embodiment, a so-called front-loading type cassette is used in which the supply of sheets P or replacement with a sheet cassette having a different size is performed by moving the cassette from the front of the apparatus.
[0016]
In FIG. 1, reference numeral 27 denotes a case-shaped cassette body, and a handle 28 for pulling out the cassette 15 from the copying machine body 1 is formed at the lower end of the front side surface 15a. An arrow A direction in FIG. 1 indicates a mounting direction of the sheet cassette 15.
[0017]
At the bottom of the cassette main body 27, an intermediate plate 29 is provided as a sheet stacking means for stacking the sheets P, and the intermediate plate 29 rotatably fixes a fixed end 29a on the sheet rear end side in the sheet conveying direction. Have been. The free end side of the middle plate 29 is configured to be able to swing upward by being urged by a later-described middle arm.
[0018]
Reference numerals 30 and 31 denote side regulating plates as width-direction regulating means, which position the sheets P stacked on the middle plate 29 in the width direction by sliding them in the width direction. The side regulating plates 30 and 31 are connected by a gear (not shown) so as to move synchronously so that the center of the sheet P does not change even when the sheet size changes. Reference numeral 32 denotes a trailing end regulating plate serving as a longitudinal direction regulating means. The trailing end regulating plate slides the sheet P stacked on the middle plate 29 in the longitudinal direction to position the sheet trailing end. The rear end regulating plate 32 is slidably attached to the sheet cassette 15 in the sheet conveying direction so that the operator can change the position according to the sheet size.
[0019]
Next, a pressurizing means is provided on the apparatus main body side facing one side surface of the cassette main body 27, and its configuration will be described below.
[0020]
Reference numeral 33 denotes an apparatus main body side plate. A front lever shaft 34 is inserted through a shaft hole 33a, one end of the front lever shaft 34 is connected to a shaft hole 35a of the front lever 35, and the other end is The arm 36 is connected. A middle lever shaft 37 is inserted into a shaft hole 33b provided substantially at the center in the longitudinal direction of the apparatus body side plate 33, and one end of the middle lever shaft 37 is connected to a shaft hole 38a of the middle lever 38. The other end is connected to a middle arm 40 via an oil damper 39.
[0021]
A link 41 is supported on the apparatus main body side plate 33. Dowels 41a and 41b protruding from both sides of the link 41 in the longitudinal direction are elongated holes 35b formed in the front lever 35 and the middle lever 38, respectively. 38b. That is, the movement of the link 41 is controlled by the front lever 35 and the middle lever 38.
[0022]
One end of a spring 42 is connected to a hole 38 c formed in the middle lever 38, and the other end of the spring 42 is connected to a hole 43 b of the rear lever 43. The rear lever 43 is supported rotatably about the hole 43a by fitting a dowel 33e protruding from the apparatus main body side plate 33 into the hole 43a, and is formed on the apparatus main body side plate 33. A dowel 43c protrudes from the hole 33c to come into contact with a cam surface 27a formed on the side surface of the cassette body 27.
[0023]
The device body side plate 33 is provided with holes 33d on both sides for fitting with a pad arm 44 as a separating means. The pad arm 44 is provided with a dowel 44b for fitting into the hole 33d. The pad arm 44 is supported rotatably about the dowel 44b with respect to the apparatus body side plate 33, and a pad holder 45 fitted to a fitting portion 44a of the pad arm 44 is provided on an upper edge of the link 41. Rotation is regulated by contacting the formed convex portion 41c. The pad arm 44 is pressed by the pickup roller 16 when the cassette is mounted, and separates the sheets P one by one when the sheet feeding operation is started.
[0024]
Reference numeral 46 denotes a pickup roller shaft into which the above-described pickup roller 16 is fitted. Reference numeral 47 denotes a sensor as a detecting means, which detects the presence or absence of the sheet P stacked on the middle plate 29.
[0025]
FIG. 2 is an explanatory perspective view of a handle 28 of the cassette. The handle 28 has a handle portion 28d, and is rotatably supported by fitting a fitting hole 28a into a dowel 48a of a handle support member 48. . A locking spring 28b protruding upward from the handle 28 and a tension spring 49 locking between the upper side of the cassette body 27 and a projection spring protruding from the opposite side of the handle 28d are urged in the direction of arrow C. A projection 28c is provided, and when the cassette body 27 is mounted on the apparatus main body, the locking projection 28b is locked on the apparatus main body to set the cassette at a predetermined position.
[0026]
The handle support member 48 is formed in a π shape, the dowels 48a are provided on both side walls, and a hole 48b is provided on the upper surface so that the locking projection 28b of the handle 28 can protrude. Elongated holes 48c are provided on both sides of the portion 48b. Then, as shown in FIG. 3, the handle supporting member 48 is attached and fixed to the cassette main body 27 with the screw 50 through the elongated hole 48c.
[0027]
The mounting position of the handle support member 48 with respect to the cassette main body 27 is slidable within the range of the elongated hole 48c. When the cassette main body 27 is mounted on the apparatus main body, the elongated hole 48c is oriented in a direction orthogonal to the sheet conveying direction. It is formed to be long. Therefore, the adjustment of the sheet position (horizontal registration) in the direction orthogonal to the sheet conveyance direction is performed by changing the position of the apparatus main body and the cassette main body 27 by sliding the handle support member 48 to change the position with respect to the cassette main body 27. It can be done by doing.
[0028]
Next, an operation of attaching and detaching the sheet cassette 15 to and from the apparatus main body will be described with reference to FIG.
[0029]
FIG. 4A shows a state immediately after the cassette main body 27 is set at a predetermined position of the apparatus main body. When the cassette main body 27 is set, the cassette main body 27 is moved in the direction indicated by an arrow A in FIG. Do not push on rails. At this time, the cam surface 27a provided on the side surface of the cassette body 27 and the dowel 43c protruding from the rear lever 43 come into contact with each other, and in conjunction with the movement of the cassette body 27, the rear lever 43 turns around the shaft hole 43a as an arrow. Rotate in the B direction. At this time, the spring 42 connected to the rear lever 43 has not been under tension until then. However, the middle lever 38 connected to the spring 42 is pulled by the rear lever 43 and the arrow D about the middle lever shaft 37 is taken as the center of the arrow D. Force to rotate in the direction works.
[0030]
When the cassette main body 27 is pushed in, the convex portion 27c protruding from the upper edge of the cassette main body 27 comes into contact with the regulating surface 51a of the lateral registration block 51, and the locking convex portion 28b of the handle 28 is It passes through the lower surface and rotates in the direction of arrow C around the fitting hole 28a by the restoring force of the spring 49, so that the lateral register block 51 is sandwiched between the convex portion 27c and the locking convex portion 28b. At this time, the front lever 36 rotates in the direction of arrow E, the middle lever 38 and the middle arm 40 rotate in the direction of arrow D, and the link 41 moves in the direction of arrow F. By this series of operations, the convex portion 41c formed on the upper edge of the link 41 pushes up the pad holder 45 in the direction of arrow G, and the pad arm 44 integrally attached to the pad holder 45 is supported by the pickup roller shaft 46. When the middle arm 40 rotates in the direction of arrow D at the same time, the free end side of the middle plate 29 shown in FIG. 1 is pushed up, and the sheet P stacked on the middle plate 29 is picked up. It is brought into contact with the roller 16.
[0031]
In the above state, when the copying operation is started and the sheet feeding operation is started, the pickup roller 16 is driven to rotate, and only the uppermost sheet P is separated and fed by cooperation with the pad arm 44, and the predetermined position is set. Is formed.
[0032]
Next, the operation when the sheet cassette 15 is pulled out from the copying machine main body 1 will be described with reference to FIG. First, the handle 28 d of the handle 28 of the cassette body 27 is gripped and rotated in the direction of arrow C ′ against the elastic force of the spring 49. As a result, the cassette main body 27 can be pulled out in the direction of arrow A 'by rotating the locking projection 28b away from the lateral registration block 51 and rotating it to a position where it can pass through the lower surface of the block 51.
[0033]
The projection 28c of the handle 28 rotates the front arm 36 in the direction of arrow E 'against the elastic force of the spring 42, and rotates the middle lever 38 and the middle arm 40 in the direction of arrow D'. Accordingly, the link 41 moves in the direction of the arrow F ', and the pad arm 44 pressed by the convex portion 41c moves in the direction of the arrow G'. Accordingly, the lifting of the middle plate 29 by the middle arm 40 is released, and the sheet P is separated from the pickup roller 16, and the pad arm 44 is also separated from the pickup roller 16.
[0034]
At this time, as shown in FIG. 5, when the mounting position of the handle support member 48 with respect to the cassette body 27 is changed in the lateral registration direction, the position of the handle 28 with respect to the cassette body 27 changes. The relative position between the apparatus main body (horizontal registration block 51) and the cassette main body 27 to be locked by the portion 28b changes. Therefore, the lateral registration of the sheet P stored in the cassette main body 27 and the apparatus main body is adjusted.
[0035]
However, the relative position between the handle 28 itself, the apparatus body, and the apparatus body side plate 33 attached to the apparatus body does not change. That is, even if the position of the handle 28 with respect to the cassette body 27 is changed, the interval between the center of rotation 28a of the handle 28 and the position where the protrusion 28c presses the forearm 36 does not change. Therefore, when the cassette body 27 is pulled out by operating the handle 28, the timing of releasing the pad arm 44 is always constant without being changed by the lateral registration adjustment. Therefore, when the cassette main body 27 is pulled out from the apparatus main body, the pressing of the sheet P is reliably released regardless of the lateral registration adjustment, and problems such as remaining sheets due to incomplete release and generation of wrinkles at the sheet end are prevented. Is what is done.
[0036]
When adjusting the position of the handle support member 48 with respect to the cassette body 27, as shown in FIG. 3A, a scale 48d is provided in the elongated hole 48c, and an arrow 50a is provided in the screw 50. It is possible to easily perform the adjustment while visually confirming how much the horizontal registration adjustment has been made.
[0037]
In the above-described embodiment, a copying machine is exemplified as an image forming apparatus. However, the present invention is not limited to this. For example, a laser beam printer, a facsimile apparatus, or another image forming apparatus such as a word processor may be used. Of course it is possible.
[0038]
【The invention's effect】
As described above, the present invention is configured such that the position where the handle is attached to the sheet storage means is slidable in a direction orthogonal to the sheet feeding direction, so that the sheet storage means is pulled out from the apparatus main body regardless of the lateral registration adjustment. In addition, the pressing means for moving the sheet stacking means and the separating means to a position where the sheet stacking means and the sheet feeding means come into contact with or separate from the sheet feeding means can be reliably operated. For this reason, problems such as the sheet remaining at the separation position when the sheet storage means is pulled out and the occurrence of wrinkles on the sheet leading end side can be solved.
[0039]
Further, when the mounting position of the handle is slid, if the slide amount can be checked on the scale, the lateral registration adjustment can be easily performed.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating a sheet feeding apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic perspective explanatory view of a handle and a handle support member.
3A and 3B are schematic explanatory views of a handle and a handle supporting member, wherein FIG. 3A is a plan explanatory view and FIG. 3B is a front explanatory view.
4A and 4B are explanatory diagrams of attaching and detaching a cassette to and from the apparatus main body, wherein FIG. 4A is an explanatory diagram at the time of mounting, and FIG.
FIG. 5 is an explanatory diagram of the relative positional relationship between the apparatus main body, the cassette main body, the handle, the apparatus main body side plate, and the sheet when the lateral registration is adjusted by changing the position of the handle with respect to the cassette main body.
FIG. 6 is a schematic diagram illustrating the configuration of an image forming apparatus having a sheet feeding device.
[Explanation of symbols]
P ... sheet, 1 ... copier body, 2 ... document table, 3 ... document pressure plate, 4 ... lamp, 5-10 ... reflection mirror, 11 ... image forming lens, 12 ... photosensitive drum, 13 ... primary charger, 14 Developing device, 15 Sheet cassette, 15a Front side, 16 Pickup roller, 17 Slip roller pair, 18 Register roller pair, 19 Transfer charger, 20 Separation charger, 21 Transport device, 22 Fixing device, 23: fixing discharge roller pair, 24: discharge roller pair, 25: discharge tray, 26: cleaning device, 27: cassette body, 27a: cam surface, 28: handle, 28a: fitting hole, 28b, 28c ... Projection, 28d Handle part, 29 Middle plate, 29a Fixed end, 30, 31 Side control plate, 32 Rear end control plate, 33 Device side plate, 34 Lever shaft, 35 Front lever, 35b , 38b ... long hole 36 front arm, 37 middle lever shaft, 38 middle lever, 39 oil damper, 40 middle arm, 41 link, 42 spring, 43 rear lever, 44 pad arm, 44a fitting portion, 45: pad holder, 46: pickup roller shaft, 47: sensor, 48: handle support member, 48a: dowel, 48b: hole, 48c: elongated hole, 48d: scale, 49: tension spring, 50: screw, 50a ... Arrow, 51 ... horizontal cash register block, 51a ... regulating surface

Claims (4)

In a sheet feeding apparatus in which a sheet storage unit in which sheets are stacked and stored is mounted on the apparatus main body and fed by a feeding unit on the apparatus main body side,
Sheet loading means capable of loading and swinging sheets mounted on the sheet storage means,
Separating means for separating a sheet disposed opposite to the feeding means,
A handle attached to the sheet storage means and having a locking portion that can be locked or unlocked with respect to the apparatus main body;
By operating the handle, pressurizing means for moving the sheet stacking means and the separating means to a position where the sheet stacking means and the separating means abut or separate from the feeding means,
With
A sheet feeding device, wherein a position where the handle is attached to the sheet storage means is slidable in a direction orthogonal to a sheet feeding direction. 2. The sheet feeding device according to claim 1, wherein a long hole is provided in a handle supporting member for supporting the handle, and the handle supporting member is attached to the sheet storage means via the long hole. 3. The sheet feeding device according to claim 2, wherein a scale is provided in a long hole portion of the handle support member so that a sliding amount of the handle with respect to the sheet storage means can be checked. A sheet feeding device according to any one of claims 1 to 3,
Image forming means for forming an image in accordance with image information on a sheet fed by the sheet feeding device;
An image forming apparatus comprising:

Images