This application claims the benefit of priority from Japanese Patent Application No. 2004-241946, filed on Aug. 23, 2004, the entire contents of which are incorporated by reference herein.
1. Field of the Invention
The present invention relates to a sheet feeding apparatus, and an image processing apparatus including this sheet feeding apparatus.
2. Description of the Related Art
Hitherto, an original feeding apparatus used in a scanner, copying machine, or the like, includes leading end regulating means for regulating leading ends of originals stacked up in an original stock unit, and a pickup roller for picking up and conveying stacked originals. The original feeding apparatus further includes a separating apparatus for separating and conveying the plural picked up and conveyed originals by one sheet each. The leading end regulating means is disposed between the pickup roller and the separating apparatus. The leading end regulating means prevents the leading end of an original from being pushed into the separating apparatus when the user stacks up a pile of originals on the original stock unit. The leading end regulating means also functions to align the leading ends of originals set by the user in the original stock unit. The pickup roller is movable to a position away from the stacking space so as not to hinder the user from stacking up the originals in the original stock unit.
Originals stacked up in the original stock unit are released from regulation of original leading ends of the original when the leading end regulating means is moved away. Then, the pickup roller descends to the top of the stacked originals and presses the originals from above. By the pickup roller, the originals are picked up and conveyed toward the separating apparatus. Driving means for moving the leading end regulating means, and driving means for raising or lowering the pickup roller, are individually provided. Or, for moving the leading end regulating means, and for raising or lowering the pickup roller, individual drive mechanisms using clutches and cams are respectively provided. Besides, as disclosed in Japanese Patent Application Laid-Open (JP-A) No. 8-310668, No. 2003-40475, and Japanese Patent Publication No. 3335973, by making use of lifting and lowering motion of the pickup roller, it is proposed to regulate the swing or the release of the regulation of the leading end regulating means.
In the prior art, however, individual driving means or individual driving mechanisms are used for moving the position of the leading end regulating means for regulating the leading ends of the originals, and for driving the pickup roller in a lifting and a lowering motion. Hence, it has been difficult to reduce the size and to lower the cost of the apparatus.
In the technologies disclosed in JP-A No. 8-310668, No. 2003-40475, and Japanese Patent Publication No. 3335973, the originals conveyed by the pickup roller are released from the swing regulation, and are advanced forward by pushing away the leading end regulating means located at the leading end regulating position. Therefore, when feeding thin originals, for example, leading ends of originals may be folded. Further, in the technologies disclosed in JP-A No. 8-310668 and Japanese Patent Publication No. 3335973, the escaping direction of swingable leading end regulating means is above the originals. Hence, if the leading end of an original is curled to the upper side, the leading end of an original may be rolled into the leading end regulating means, which is pushed away upward, and paper feeding may be disturbed.
The invention is devised to solve the problems of the prior art, and it is an object thereof to provide a sheet feeding apparatus simplified in the structure of leading end regulating means and the pickup roller lifting and lowering mechanism. It is another object of the invention to provide a sheet feeding apparatus capable of feeding a wide variety of sheets smoothly, while lowering the cost by reducing the size of the apparatus and curtailing the number of parts.
A representative configuration of the invention for achieving the objects includes a feeding unit for feeding sheets stacked up in a sheet stock unit, and a leading end regulating member for regulating the leading ends in a feeding direction of sheets stacked up in the sheet stock unit, in which the feeding unit is provided so as to contact with or move away from the sheets, and the leading end regulating member moves between a regulating position for regulating the leading end of a sheet in the sheet conveying route, and a retreat position for releasing from a leading end regulation of a sheet by moving away from the sheet conveying route, the leading end regulating member holds the feeding unit at a position away from the sheets at the regulating position, and brings the feeding unit into contact with sheets at the retreat position.
According to the invention, the lifting and lowering drive mechanism of feeding means required hitherto can be omitted, and the apparatus size is reduced, the number of parts is curtailed, and the cost is lowered, and further, various types of sheets can be fed smoothly, including thin sheets and curled sheets, so that the reliability of the apparatus is enhanced.
a) and 5(b) show essential parts of a sheet feeding apparatus in the second embodiment, in which
Referring now to the drawings, preferred embodiments of the invention are specifically described below.
The following embodiments relate to a sheet feeding apparatus for originals intended to feed originals or sheets like originals to be read one by one. The invention is not limited to this example, alone, but the same effects are obtained when it is applied in a sheet feeding apparatus for printing a medium intended to feed recording papers or other sheets to be recorded one by one.
The following embodiments show an example of an image reading apparatus as an image processing apparatus. But not limited to this example alone, the invention may also be applied to a printer or other image processing apparatus, including an image recording unit for recording an image on a sheet to be recorded. The invention is also applicable to an image reading unit for reading an image on a sheet to be read. Further, the invention is applicable to a copying machine, including an image recording unit for recording an image on a sheet to be recorded, other image processing apparatus, such as a facsimile apparatus, or other image processing apparatuses, such as a complex machine combining these functions. The same effects are obtained by applying the invention in the sheet feeding apparatus used in such an image processing apparatus.
In the following embodiments, a sheet feeding apparatus integrally incorporated in an image processing apparatus is explained, but the invention is not limited to this embodiment alone, and the sheet feeding apparatus may be detachable from the image processing apparatus, and the same effects are obtained by applying the invention in the sheet feeding apparatus.
A first embodiment of the invention is explained with reference to the drawings.
In
Reference numeral 111 is a pickup roller as feeding means. The pickup roller 111 feeds sheets S stacked up in the sheet stock unit 100a toward the inside of the apparatus. This pickup roller 111 is supported by a roller holding member 112. The roller holding member 112 is supported rotatably about shaft 113a of a feed roller 113 described below. The pickup roller 111 is supported movably between the abutting position abutting against the top of sheets S stacked up in the sheet stock unit 100a and the departing position not disturbing the stacking, about the shaft 113a of the feed roller 113. The feeding unit is composed of pickup roller 111 and roller holding member 112.
Reference numeral 115 is a sheet regulating member as leading end regulating means. The sheet regulating member 115 is intended to prevent the leading ends of sheets set by the user in the sheet stock unit 100a from being pushed into the separating apparatus 110. The sheet regulating member 115 is also to align the leading ends of sheets. The sheet regulating member 115 is designed to move away from the conveying route of sheets S when the image forming apparatus starts a scanning operation. The sheet regulating member 115 is capable of swinging on the lower side as a hinge. The sheet regulating member 115 is a member capable of selecting a standing state and an inclined state. The sheet regulating member 115 is held in a standing state in a stopped state of the image reading apparatus 100, that is, the regulating position (POSITION A in
Reference numeral 110 is a separating apparatus (separating means) for sorting a plurality of sheets into each sheet. The separating apparatus 110 is composed of a feed roller 113 rotating normally in a conveying direction, and a separating roller 114 rotating reversely. The separating apparatus 110 separates the sheets fed by the pickup roller 111 into each sheet, and conveys to the downstream side. As shown in an overall configuration of the image forming apparatus in
An image reading operation of the image reading apparatus 100 having such a configuration is explained below. When an image reading operation is started, the sheet regulating member 115 moves from the upright regulating position for regulating the leading ends of sheets (double dotted chain line position in
The image of sheet S is read by the front image reading unit 140 and back image reading unit 150. That is, the image formed on the front or back of the sheet S is scanned while passing through the front image reading unit 140 or back image reading unit 150, and the front or back image information is issued outside as an electrical signal. After the image is read, the sheet S is conveyed by roller pairs of conveyance rollers 123, 124, and driven rollers 133, 134, and discharged into the discharge stock unit 100b.
Referring to
The sheet feeding apparatus in the image reading apparatus includes, as described above, pickup roller 111 for feeding the sheets S stacked up in the sheet stock unit 100a, and separating apparatus 110 for separating the plurality of sheets S into each sheet. The sheet feeding apparatus further includes a sheet regulating member 115 for regulating the leading ends in the feeding direction of sheets S stacked up in the sheet stock unit 100a.
Further, as mentioned above, the pickup roller 111 is provided so as to contact with or depart from the sheets S. The sheet regulating member 115 is designed to move between the regulating position for regulating the leading ends of sheets S shown in
The sheet regulating member 115 moves to the regulating position shown in
The drive mechanism of the sheet regulating member, and the relation between the sheet regulating member and the pickup roller are explained below.
As shown in
The drive mechanism of the sheet regulating member 115 is not limited to the configuration explained above, and similar effects are obtained by using, for example, a solenoid.
The roller holding member 112 has a contact surface 112a to contact with the leading end portion 115a of the sheet regulating member 115 as shown in
Further, as shown in
A second embodiment of the invention is described by referring to the drawings.
A general overall configuration of an image reading apparatus, including the sheet feeding apparatus, is the same as in the foregoing embodiment, and the same members are identified with the same reference numerals, and an explanation is not described. Characteristic portions of the embodiment are described below.
In this configuration, as shown in
The pickup roller 111 is rotated and driven by a drive transmission mechanism of gears and other components provided at the roller end. As shown in
The motion of sheet regulating member 215 and pickup roller 111 is explained. At the home position, the sheet regulating member 215 is in an upright (inverted) state, and the sheet regulating member 215 is located at the regulating position for regulating the leading ends of sheets S (solid line position in
When the pickup roller 111 begins to rotate in the sheet feeding direction, the sheet regulating member 215, provided coaxially on the pickup roller 111, swings to incline from the regulating position indicated by a solid line in
When all sheets in the sheet stock unit are fed, or interruption of sheet feeding is instructed, the pickup roller 111 rotates reversely. The sheet regulating member 215 receives this reverse driving force by way of the torque limiter 230. Therefore, the sheet regulating member 215 moves from the retreat position indicated by double dotted chain line in
According to the embodiments, the same effects as in the foregoing embodiment can be obtained, and further complicated structure of each driving force transmission route can be avoided, because the sheet regulating member 215 is provided rotatably on the pickup roller 111 coaxially.
a) and 5(b) are diagrams of a paper feeding and conveying apparatus in a third embodiment.
In the foregoing embodiments, the separating apparatus 110 is composed of feed roller 113 and separation roller 114, but the invention is not limited to this structure alone, and, for example, the separating apparatus may be composed of feed roller 113 and separation pad 116, and by using such a separating apparatus, the same effects as in the foregoing embodiments may be obtained, as shown in
Number | Date | Country | Kind |
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2004-241946 | Aug 2004 | JP | national |
Number | Name | Date | Kind |
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4905984 | Haigh | Mar 1990 | A |
6307621 | Endo et al. | Oct 2001 | B1 |
6792241 | Nakagawa et al. | Sep 2004 | B2 |
20030026633 | Nakagawa et al. | Feb 2003 | A1 |
Number | Date | Country |
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06305595 | Nov 1994 | JP |
8-310668 | Nov 1996 | JP |
3335973 | Aug 2002 | JP |
2003-40475 | Feb 2003 | JP |
Number | Date | Country | |
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20060038339 A1 | Feb 2006 | US |