1. Field of the Invention
The present invention relates to a sheet feed device for clamping and feeding a sheet, such as a sheet feed device used for an image forming apparatus such as a copying machine and a laser beam printer.
2. Description of the Related Art
Conventionally, the image forming apparatus such as a copying machine and a laser beam printer include the configuration having a door to be opened or closed with respect to the apparatus main body at the time of for example the paper jamming process. In order to facilitate the paper jamming process, there is a configuration of opening the sheet feeding path (sheet clamping) by separating a feed roller pair for clamping and feeding the sheet according to the door opening and closing operation, that is, by separating the rollers comprising the roller pair.
As to the configuration of the door to be opened or closed, for example, one to be opened or closed around the lower side of the door comprising the apparatus side surface exterior as the rotation center, one to be slid and moved in the right and left direction as it is (substantially parallel to the apparatus installation surface), or the like can be presented. For preventing damage of the feed roller pair to be moved away at the time of releasing clamping of the sheet as mentioned above, a configuration of opening or closing by moving parallel the other roller with respect to one roller in the roller axis direction is preferable.
For example, as shown in
However, in the case the rotation shaft of the door to be opened or closed with respect to the apparatus main body is provided on the lower side of the door, or in the case the door is slid and moved in the right and left direction in the above-mentioned conventional examples, unless the grip for opening or closing the door is disposed in the substantial center of the door, the opening and closing operation cannot be executed smoothly, and thus a problem of the poor operability is involved.
Furthermore, in the case the rotation axis of the door is provided in the lower side of the door, at the time of opening or closing the door, the user should open the door while supporting the same with the hands, and a problem of the poor operability is involved.
Moreover, in the case the door is slid and moved in the right and left direction as it is, the door can hardly be slid and moved smoothly unless the front and rear sides of the door are well balanced (in the direction substantially orthogonal to the moving direction), and thus a problem of the poor operability is involved. Furthermore, for sliding and moving the door easily and smoothly, a problem of the complication of the mechanism for sliding and moving the door is involved.
Therefore, in order to improve the user operability, as shown in
As shown in
For example, in the case the other roller 10 of the feed roller pair is an intermediate transfer belt for bearing a toner image (the reference numeral 152 in
Accordingly, an object of the present invention is to provide a sheet feed device and an image forming apparatus with a good user operability even in the case of separating and releasing a feed roller pair by opening a door from the front side to the deeper side with the rotation axis provided on the deeper side, capable of preventing damage of the members such as the feed roller pair according to the door opening and closing operation.
Still another object of the present invention will become apparent while reading the following detailed explanation with reference to the accompanied drawings.
Hereinafter, with reference to the drawings, preferable embodiments of the present invention will be explained in detail. However, the size of the constituent parts, the material, the shape, the relative arrangement thereof, or the like described in the following embodiments can be optionally changed according to the configuration of the apparatus to adopt the present invention and the various conditions so that the scope of the present invention is not limited thereby unless there is specific description.
First, with reference to
In
An image forming part 115 comprises a photosensitive drum 112, a charge roller 106 for evenly charging the surface of the photosensitive drum 112, a laser unit 109 for forming a latent image on the photosensitive drum 112 by irradiating an image light, a rotary developing unit 151 for forming a toner image on the photosensitive drum 112, an intermediate transfer belt 152 in which the toner image developed on the surface of the photosensitive drum 112 is transferred, a transfer inner roller 10 for collectively transferring the toner image on the intermediate transfer belt 152 to a sheet S, a cleaner 126 for removing the toner remaining on the photosensitive drum 112 after transferring the toner image, or the like. The photosensitive drum 112 develops an electrostatic latent image formed by a light image irradiated from the laser unit 109 on the surface of the photosensitive drum 112 charged by the charge roller 160 and successively transfer and superimpose the same onto the intermediate transfer belt 152. The toner image on the intermediate transfer belt 152 is transferred onto the sheet S collectively by the transfer inner roller 10 of the secondary transfer part. The sheet S is supplied selectively one by one from a sheet cassette 127 by a feeding part 128.
A fixing device 122 for fixing a toner image on the sheet S being fed as a permanent image, and a discharge roller pair 124 for discharging the sheet S with the toner image fixed by the fixing device 122 from the image forming apparatus main body 101 are provided successively on the downstream side of the image forming part 115. A discharge part 125 for receiving the sheet S discharged by the discharge roller pair 124 is provided outside the image forming apparatus main body 101.
Furthermore, the image forming apparatus according to this embodiment comprises a secondary transfer part having a transfer outer roller 5 and a transfer inner roller 10 as the feed roller pair for clamping and feeding the sheet, and a sheet feed device having doors 1, 2 having the rotation axis on the apparatus main body deeper side, for supporting the one transfer outer roller 5 of the secondary transfer part.
As shown in
Hereinafter, with reference to
The ordinary state is the door closed state shown in
The outer door 1 is to be rotated with respect to the apparatus main body rear side plate 9 by the outer door hinge shaft 1a as the rotation axis of the entire door, and the apparatus main body front side as the free end is engaged with the apparatus main body front side plate 8 by an unshown lock mechanism. The inner door 2 is rotated with respect to the outer door 1 by the inner door hinge shaft 2, and it positions the door and stop the rotation thereof by receiving the positioning part 1c provided on the free end side of the outer door 1 at the positioning part 2e provided on the free end side. Moreover, the inner door 2 has the transfer outer roller 5 constituting the secondary transfer part as the feed roller pair such that the transfer outer roller is forced by the pressure springs 4a, 4b so as to press the transfer inner roller 10. According to the pressure, the sheet S is clamped and fed by the transfer roller pair 5, 10 via the intermediate transfer belt 152. Moreover, the gap between the outer door 1 and the inner door 2 constituting the door forms a feeding path for guiding the sheet (see
Next, the movement of the above-mentioned constituent elements at the time of opening the door will be explained. As shown in the state in
Then, as shown in
Moreover, as shown in
At the time of closing the door, it is operated in the opposite order (FIG. 5→FIG. 1→FIG. 4→
As mentioned above, according to this embodiment, even in the case of separating and opening the feed roller pair by opening the door from the front side to the deeper side with the rotation axis provided on the deeper side, by gradually opening the inner door with respect to the outer door 1 about the outer door hinge shaft 1a, since one of the roller 5 of the feed roller pair 5, 10 is moved substantially parallel with respect to the other roller 10 in the axis direction, the user operability is good. Furthermore, since the feed roller pair 5, 10 is opened or closed substantially parallel in the axis direction, damage of the feed roller pair accompanied by the door opening or closing operation can be prevented.
Although the configuration of supporting or releasing the support of the opening angle β of the outer door 1 and the inner door 2 is provided in the lock mechanism shown in
As shown in
Since the other schematic configuration of the apparatus is same as that shown in
According to the lock mechanism, at the time of separating and opening the feed roller pair by opening the doors from the front side to the deeper side with the rotation shaft provided on the deeper side, the user operability is good. Furthermore, since the feed roller pair 5, 10 is opened or closed substantially parallel in the axis direction, damage of the feed roller pair accompanied by the door opening or closing operation can be prevented.
Although an example of the transfer roller pair 5, 10 constituting the secondary transfer part is explained as the feed roller pair for clamping or releasing the clamp according to the opening or closing operation of the doors 1, 2 in the configuration shown in
In an image forming apparatus for transferring a toner image formed on the photosensitive drum 31 as the image bearing member in an image forming part onto a sheet fed from a feeding part by the transfer roller 32, as shown in
Either in the case of this configuration, or in the case of separating and opening the feed roller pair by opening the doors from the front side to the deeper side with the rotation axis provided on the deeper side, the user operability is good. Furthermore, since the feed roller pair 31, 32 is opened substantially parallel in the axis direction, damage of the feed roller pair accompanied by the door opening or closing operation can be prevented.
Furthermore, the next configuration can also be adopted. As the feed roller pair for clamping or releasing the clamp according to the opening or closing operation of the doors 1, 2, a roller pair comprising each of the rollers of the feed roller pair to be driven by a gear can be used.
Here, a registration roller pair 41, 44 is shown as an example. As shown in
Since the other schematic configuration of the apparatus is same as that shown in
According to the registration roller pair of the configuration, by disposing the registration roller 44 of the registration roller pair on the inner door 2 of the doors 1, 2 shown in
Although an example of one pair of the feed roller pair for clamping or releasing the clamp according to the opening or closing operation of the doors comprising the outer door and the inner door in a sheet feed device or an image forming apparatus is explained in this embodiment, the present invention is not limited thereto, and a plurality of the feed roller pairs for clamping or releasing the clamp according to the opening or closing operation of the doors comprising the outer door and the inner door in a sheet feed device or an image forming apparatus can be provided.
For example, both the transfer roller pair 5, 10 as the feed roller pair and the registration roller pair 41, 44 as the feed roller pair may be opened or closed substantially parallel in the axis direction according to the opening or closing operation of the doors comprising the outer door 1 and the inner door 2. According to this configuration, not only the same effect as in the above-mentioned embodiment can be obtained but also the user operability can further be improved since the feeding path can be opened in a wider range.
Out of the doors comprising the outer door 1 and the inner door 2, the inner door 2 comprises a first feed part 201 for feeding a sheet with respect to the apparatus main body, and a second feed part 202 for feeding the sheet with respect to an outer door 1. The first feed part 201 and the second feed part 202 constituting the inner door 2 have the float configuration with springs 207, 208 provided therebetween. In the figure, the reference numerals 201a, 201b denote limiting members for limiting separation of the feed parts 201, 202 by more than a predetermined amount by the springs 207, 208.
In the first feed part 201 disposed on the apparatus main body side of the inner door 2, one of the transfer outer roller 5 constituting the secondary transfer part as the feed roller pair is forced by a spring 209 so as to be supported rotatably by a supporting member 217 swayable about the fulcrum 217a. Furthermore, one of the registration roller 44 of the registration roller pair as the feed roller pair is forced by a spring 211 so as to be supported rotatably by a bearing 210 movable parallel by an unshown slide mechanism. Moreover, the first feed part 201 is positioned by positioning parts 201c, 201d provided on the first feed part 201 side and positioning parts 203, 204a provided on the apparatus main body side.
Moreover, in the figure, the reference numeral 201e denotes a feed guide provided in the inner door 2 for forming a feeding path for guiding a sheet on the first feed part side of the inner door 2. The reference numerals 204, 212 denote feed guides provided on the apparatus main body side for forming the feeding path for guiding a sheet together with the feed guide on the first feed part side of the inner door 2.
In contrast, in the second feed part 202 disposed on the outer door side of the inner door 2, one of a feed roller 214 of a feed roller pair 213, 214 for feeding a sheet in the feeding path with respect to the outer door 1 is forced by a spring 216 so as to be supported rotatably by a bearing 215 movable parallel by an unshown slide mechanism. Moreover, the second feed part 202 is positioned by positioning parts 202a, 202b provided on the second feed part 202 side and outer door positioning parts 205a, 206a provided on the outer door 1 side.
Moreover, in the figure, the reference numerals 205, 206 denote feed guides provided in the outer door 1 for forming a feeding path for guiding a sheet together with the feed guide formed by the second feed part 202 of the inner door 2.
Since the other schematic configuration of the apparatus is same as that shown in
Accordingly, in the apparatus for separating and opening the feed roller pair by opening the door from the front side to the deeper side with the rotation axis provided on the deeper side, since a plurality of the feeding paths disposed between the door and the apparatus main body can be opened or closed, and the feed parts (a plurality of the feed roller pairs) for clamping and feeding the sheet in the feeding paths can be opened or closed substantially parallel in the axis direction, not only the damage of the feed roller pair accompanied by the door opening or closing operation can be prevented but also the user operability can further be improved.
Since the second feed part disposed between the outer door 1 and the inner door 2 is the feed roller pair 213, 214 and the offset amount of the roller with respect to the normal direction of the roller and the hinge shaft in the roller axis direction is small, the roller can hardly be flawed, and even in the case it is flawed, since the roller pair is the feed roller pair as mentioned above, the feed failure cannot be generated by the feeding force deterioration derived from several flaws.
Although the number of the developing units provided in the rotary developing unit as the rotation type developing unit has not been described specifically in the above-mentioned embodiment, the number of use is not limited, and it can be set optionally as needed.
Moreover, although an example of a copying machine as the image forming apparatus is shown in the embodiment, the present invention is not limited thereto. For example, other image forming apparatus such as a printer, and a facsimile machine, image forming apparatus using a transfer drum instead of a transfer belt as the intermediate transfer member for transferring and superimposing toner images of each color successively on the transfer drum, and transferring the transferred toner images collectively onto a transfer medium, or image forming apparatus using a transfer material bearing member such as a transfer feed belt, and a transfer drum for transferring and superimposing toner images of each color successively on the transfer member bore on the transfer material bearing member may be used as well. By adopting the present invention to the sheet feed device used for the image forming apparatus, the same effect can be obtained.
Moreover, although an example of a sheet feed device for feeding a sheet such as a recording paper as the recording subject has been described in the embodiment, the present invention is not limited thereto. For example, by adopting the present invention to the sheet feed unit for feeding a sheet such as an original as the reading subject, the same effect can be obtained.
Moreover, although an example of the electrophotographic system as the recording system has been described in the embodiment, it is not limited thereto. For example, another recording system such as the ink jet system can be used as well.
Number | Date | Country | Kind |
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2003-061889 | Mar 2003 | JP | national |
Number | Name | Date | Kind |
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3661383 | Morrison | May 1972 | A |
6145828 | Arai | Nov 2000 | A |
6308029 | Yamamoto | Oct 2001 | B1 |
6564019 | Ahn et al. | May 2003 | B2 |
6782223 | Yoshida | Aug 2004 | B2 |
Number | Date | Country | |
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20040175210 A1 | Sep 2004 | US |