JP2008013373A - Automatic document feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic document feeder capable of preventing fingers of a user from touching a paper feeding roller. <P>SOLUTION: This automatic document feeder 10 includes a document feeding tray 11 for placing a document, a document feeding mechanism 12 having a casing structure and having the paper feeding roller 21b feeding the document to a document reading position, and a protective cover member 41 arranging and covering an opening part 21c receiving the document feeding mechanism 12 from the document feeding tray 11. The protective cover member 41 is rotatably supported at its one end by a document feeding mechanism casing, and is provided with a projection part 51 on its free end side for protecting the paper feeding roller 21b in a state of closing the protective cover member 41. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention is used in an image forming apparatus such as a copying machine, a printer, or a facsimile machine, and automatically separates a plurality of documents one by one and automatically feeds them to an image reading device such as a scanner device. It is about.

In general, an image forming apparatus includes an automatic document feeder that separates a large number of documents (hereinafter referred to as a document bundle) one by one and feeds them to an image reading device such as a scanner device. This type of automatic document feeder separates documents one by one from a document stacking unit (document feeding tray) on which a document bundle is placed and a document bundle placed on the document placing unit. And a document feeding mechanism for feeding paper.

In the single-sided printing mode, a document fed from the document feeding mechanism is sent to a document reading position (for example, an image reading device), where an image on the document is read, and then a document feed tray. The paper is discharged to a document discharge tray or the like disposed on the lower side. Then, according to the image data read by the image reading device, for example, an image is formed on a recording sheet or the like according to an electrophotographic process.

On the other hand, in the double-sided printing mode, the original on which the image on one side is read by the image reading device is reversed, and is fed again to the image reading device by the document feeding mechanism, and the image on the other side is read. It will be. For this reason, in the automatic document feeder, a document reversing unit (document reversing tray) is disposed between the document feeding tray and the document discharge tray, and the document reversing tray is used in the duplex printing mode. The original is reversed.

Then, a document reversing tray is arranged below the document feed tray, so that the document is switched back and then reversed and returned to the reading position, thereby shortening the document transport path when reading both sides of the document. ing.

As described above, the automatic document feeder has a document feeding tray, a document feeding mechanism, a document reversing tray, and a document discharge tray. The documents are reversed one by one on the document reversing tray. As a result, the distance between the document feed tray and the document reversing tray is extremely small.

On the other hand, in order to protect the document feeding mechanism, the document feeding mechanism is covered with a protective cover member that can be opened and closed. In the document feeding mechanism, when a document jam (hereinafter simply referred to as jam) occurs on the document feeding tray side, the protective cover member is opened to perform jam processing, while jamming occurs on the document reversing tray side. When this occurs, because the document reversing tray is located below the document feeding tray, the protective cover member is opened, and then the document feeding tray is lifted to expose the document reversing tray and jam processing is performed. Will do. The protective cover member functions as a document conveyance guide. That is, the protective cover member also serves as a document conveyance guide.

By the way, in the automatic document feeder as described above, a user who notices a miscopy or the like may suddenly pull out a document on the document reversing tray during copying or the like. If the document does not exist, the automatic document feeder may continue unnecessary operations. In order to prevent such a problem, in the double-sided printing mode, when the document transported to the document reversing tray is pulled out by the user, the transport operation is stopped and a jam is displayed to stop the waste transport operation. (See Patent Document 1).
JP-A-10-161361 (paragraph (0042) to paragraph (0047), FIGS. 6 and 10)

As described above, when a jam occurs in the document feeding mechanism, the protective cover member is opened anyway. When opening the protective cover member, hold the free end side of the protective cover member. If the mechanism opens the protective cover member, it may inadvertently touch the paper feed roller provided in the document feed mechanism. If the user touches the paper feed roller, an unexpected failure will occur in the paper feed roller. May end up. Further, if the user accidentally touches the paper feed roller that is being rotated with a finger or the like, the user may be injured by the paper feed roller.

On the other hand, when opening and closing the protective cover member, for example, if a separate opening and closing lever is provided and the protective cover member is opened and closed by operating the lever, the paper feed roller is hardly touched as described above. This time, there is a problem that the mechanism for opening and closing the protective cover member becomes complicated and the number of parts increases.

Furthermore, when a jam occurs on the document reversing tray side, it is necessary to open the protective cover member and lift the document feeding tray. However, it is troublesome to perform the jam processing with the document feeding tray lifted. For this reason, a mechanism such as a stopper for holding the document feed tray in a lifted state is required, and the number of parts also increases in this respect.

An object of the present invention is to provide an automatic document feeder that does not touch a paper feed roller in a document feeding mechanism when a protective cover member is opened and closed.

Another object of the present invention is to provide an automatic document feeder that can easily perform jam processing by reducing the number of parts.

  An automatic document feeder according to the present invention includes a document placement portion on which a document is placed, a document feed mechanism having a feed roller for feeding the document to a document reading position, and the document feed mechanism. A protective cover member that covers and covers an opening for receiving a document from the document placing portion, and the sheet feeding in a state where the protective cover member is closed on a side of the opening of the protective cover member A protrusion for protecting the roller is provided (claim 1).

As described above, if a protrusion that protects the paper feeding roller in a state where the protective cover member is closed is provided on the side of the opening of the protective cover member, the user's finger toward the opening is provided. In some cases, the finger cannot be inserted at the position corresponding to the paper feed roller, and the paper feed roller is not touched by mistake.

In the above configuration, the document feeding mechanism has a housing structure, and the protective cover member is rotatably supported at one end by the housing of the document feeding mechanism, and the free end side is the opening side. And it is desirable for the said free end side to function as a site | part operated with a finger, when opening the said protective cover member (Claim 2).

According to this configuration, even when a finger is inserted into the gap when opening the protective cover member with the free end side of the protective cover member, the finger cannot be inserted at a position corresponding to the paper feed roller, Never accidentally touch the paper feed roller.

For example, when the protective cover member is closed, the protruding portion desirably protrudes downward from the other portion of the free end (Claim 3). Further, it is particularly desirable that the width of the protruding portion in the axial direction of the paper feed roller is longer than the axial length of the paper feed roller.

In this way, when the protective cover member is closed, the protruding portion protrudes downward from the other portion of the free end, and the width of the protruding portion in the feed roller axial direction is the axial length of the feed roller. If it is longer than this, when the protective cover member is formed, the projecting portions can be formed together, and the paper feed roller can be reliably protected.

According to the present invention, the projecting portion that protects the paper feed roller in a state in which the protective cover member is closed is provided on the opening portion side of the protective cover member. Even if the finger is inserted, the finger cannot be inserted at a position corresponding to the paper feed roller, and there is an effect that the finger is not touched by mistake.

Further, in the present invention, when the protective cover member is closed, the protruding portion protrudes downward from the other portion of the free end, and the width of the protruding portion in the feed roller axial direction is set to the axial direction of the feed roller. Since the length is longer than the length, when the protective cover member is formed, the projecting portions can be formed together, and the sheet feeding roller can be reliably protected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention only to the description unless otherwise specified. It is just an example.

First, referring to FIG. 1, an illustrated automatic document feeder 10 is used together with an image forming apparatus (for example, a copying machine) and is disposed on the upper surface side of a main body of an image forming apparatus (not shown). The automatic document feeder 10 includes a document feed tray 11 and a document feed mechanism 12, and a document bundle is placed on the document feed tray 11. In the document feeding mechanism 12, the documents are separated one by one from the document bundle placed on the document feeding tray 11, and an image reading position (for example, an image reading device: FIG. (Not shown).

Although not shown in FIG. 1, a document reversing tray is disposed on the lower side of the document feeding tray 11, and as described above, a result of conveying the documents one by one on the document reversing tray. The distance between the document reversing tray and the document feed tray 11 is very small. A document discharge tray may be disposed below the document reversing tray.

The automatic document feeder 10 is connected to the image forming apparatus main body by, for example, a hinge mechanism, and can be opened and closed with respect to the image forming apparatus main body. The document feeding mechanism 12 is disposed on the rear side of the document feeding tray 11, and the document feeding mechanism 12 includes a document feeding roller unit (hereinafter simply referred to as a sheet feeding roller unit) 21. The document feed roller unit 21 includes a roller housing 21a, a pickup roller (pickup roller) 21b, a feed roller (feed roller: not shown), a separation mechanism described later, and the like. The pickup roller 21b and the feed roller are housed in a roller housing 21a, and the separation mechanism is provided on the base side of the automatic document feeder 10 so as to face the feed roller. The pickup roller and the feed roller collectively function as a paper feed roller.

The upper surface of the roller housing 21a is flat and extends leftward in the figure, and an opening 21c is formed at the right end in the figure. The aforementioned pickup roller 21b is accommodated in the roller housing 21a and is rotatably supported by the roller housing 21a by a shaft body (not shown) extending in a direction orthogonal to the longitudinal direction of the roller housing 21a. A part of the outer peripheral surface of the pickup roller 21b is exposed from the upper surface of the roller housing 21a.

As shown in the figure, a shaft body 31 is rotatably supported between the side surfaces 12b of the casing (feeding mechanism casing) 12a of the document feeding mechanism 12 so as to be orthogonal to the longitudinal direction of the roller housing 21a. The shaft body 31 passes through the roller housing 21a in the vicinity of the left end portion of the roller housing 21a. The shaft body 31 is rotationally driven by a motor or the like. A feed roller (not shown) is connected to the shaft body 31 and is accommodated in the roller housing 21a.

The roller housing 21a is rotatably supported by the shaft body 31, and is lowered when paper is fed (document reading), and the pickup roller 21b is in contact with the upper surface of the document bundle. On the other hand, when no paper is fed, the roller housing 21a is raised, and the pickup roller 21b is separated from the document surface. The bundle of documents placed on the document feed tray 11 is inserted into the roller housing 21a through the opening 21c, and the document is picked up by the pickup roller 21b. Although not shown, as described above, the base side of the automatic document feeder 10 is provided with a separation mechanism (for example, a retard roller, a separation pad, etc.), and the document picked up by the pickup roller 21b by the separation mechanism. In this case, only one of the sheets is separated and the document is fed to the image reading position by the feed roller 31a.

One end (left end in the figure) of the document feed tray 11 is rotatably attached to a front end (right end in the figure) of the feeding mechanism housing 12a by a shaft member extending in a direction orthogonal to the longitudinal direction of the roller housing 21a. As will be described later, the document feed tray 11 rotates around the shaft member.

The document feed tray 11 is provided with a document guide 11a for adjusting the document size so as to be movable in a direction orthogonal to the longitudinal direction of the roller housing 21a. When the document is placed, the document guide 11a is adjusted to adjust the document guide 11a to the document size.

On the other hand, one end of the protective cover member 41 is rotatably attached to the rear end (left end in the figure) of the feeding mechanism housing 12a by a shaft member extending in a direction orthogonal to the longitudinal direction of the roller housing 21a. When the protective cover member 41 is rotated and the protective cover member 41 is opened (the state shown in FIG. 1 is the state in which the protective cover member 41 is opened), the document feeding mechanism 12 is exposed. The protective cover member 41 is provided with a stopper member (not shown). When the protective cover member 41 is opened at a predetermined angle, the protective cover 41 is held at that position by the stopper member.

In the illustrated example, this predetermined angle is an angle at which the weight of the protective cover member is applied to the rear side even when the protective cover member is opened, and the protective cover member 41 is held by the stopper member. Then, the protective cover member 41 does not naturally rotate in the closing direction.

If the front end (right end in the figure: free end) of the protective cover member 41 is grasped by hand from the state shown in FIG. 1 and is rotated to the front side around the shaft member, the protective cover member 41 is rotated in the closing direction. Thus, the document feeding mechanism 12 is covered.

An engaging portion 41c is provided outside the side surface 41b of the protective cover member 41, and this engaging portion 41c is provided inside the side surface of the feeding mechanism housing 12a when the protective cover member 41 is closed. Locked to the locking portion 12c. When the protective cover member 41 is opened, if the free end of the protective cover member 41 is held by hand and pulled upward, the engaging portion 41c is detached from the locking portion 12c and rotates.

By the way, when the protective cover member 41 is closed, the document feeding mechanism 12 is covered with the protective cover member 41, but the document feeding tray 11 is moved to the document feeding mechanism 12, that is, the feeding roller 21b. When the protective cover member 41 is closed in order to feed the document, a gap exists between the free end of the protective cover member 41 and the bottom surface of the feeding mechanism housing 12a. The distance is such that a finger can be inserted because the protective cover member 41 is rotated by holding the free end of the protective cover member 41 when opening.

Therefore, when opening the protective cover member 41, a finger is inserted into the gap, but the pickup roller 21b is located slightly behind the free end of the protective cover member 41. When the protective cover member 41 is opened with the vicinity of the center of the protective cover member 41, a finger may inevitably touch the pickup roller 21b.

In the example shown in FIG. 1, a protruding portion (gap restricting portion) 51 is formed at the center of the free end of the protective cover member 41, and the length of the protruding portion 51 (perpendicular to the longitudinal direction of the roller housing 21a). Is longer than the width of the pickup roller 21b (the width in the direction perpendicular to the longitudinal direction of the roller housing 21a). That is, the free end portion of the protective cover member 41 is partially formed with a wide width, and the wide portion becomes the protruding portion 51. When the protective cover member 41 is closed, the gap of the portion corresponding to the pickup roller 21b is reduced by the protruding portion 51, and the finger cannot be inserted.

In this way, when the protective cover member 41 is closed, the gap defined by the free end of the protective cover member 41 and the bottom surface of the feeding mechanism housing 12a is larger than the other portions at the position corresponding to the pickup roller 21b. Becomes too small to insert a finger.

Therefore, when the protective cover member 41 is opened, the finger is inserted at a portion other than the portion where the protruding portion 51 is formed to hold the protective cover member 41, and the finger does not touch the pickup roller 21b.

Next, processing when a document jam (jam) occurs will be described. Assuming that a jam has occurred between the document feed tray 11 and the document feeding mechanism 12, the protective cover member 41 is gripped by hand and the protective cover member 41 is rotated as described above. When the protective cover member 41 is opened, the document feeding mechanism 12 is exposed. Therefore, the document jammed in the document feeding mechanism 12 may be removed. Then, after the jam processing, the protective cover member 41 is closed as described above.

At this time, as described above, since the finger cannot be inserted into the gap at the portion corresponding to the pickup roller 21b, the pickup roller 21b is not touched with the finger. Further, if the protective cover member 41 is opened to a predetermined angular position, the protective cover member 41 is held by the stopper member. As a result, the protective cover member 41 does not rotate in the closing direction even if the hand is released. Can be jammed.

On the other hand, when a jam occurs between the document feeding mechanism 12 and the document reversing tray, the protective cover member 41 is opened as described above, and then the document feeding tray 11 is pulled up to Rotate around the member. Then, as shown in FIG. 2, when the upper surface of the document feed tray 11 is brought into contact with the free end (projecting portion 51) of the protective cover 41 and the hand is released, the document feed tray 11 is moved by the protective cover member 41. Will be supported.

At this time, since the document feed tray 11 is rotated by more than 90 ° from the mounting position shown in FIG. 1, it does not rotate to the original position even if the hand is released.

As described above, after the document feeding tray 11 is rotated and supported by the protective cover member 41, a document jammed in the document feeding mechanism 12 may be processed. Note that the document reversing tray is not shown in FIG. Then, after the jam processing is performed, the document feed tray 11 is rotated to the original position, and the protective cover member 41 is closed.

In this way, when the protective cover member 41 is opened, it is possible to avoid touching the pickup roller acting as the paper feed roller with a finger, and when the document feed tray is opened, the protective cover member is Since the document feeding tray is supported, there is no need to provide a separate member for supporting the document feeding tray when the document feeding tray is opened. As a result, the number of parts can be reduced, and jam processing can be easily performed.

1 is a perspective view showing an example of an automatic document feeder according to the present invention with a protective cover member opened. FIG. FIG. 2 is a perspective view illustrating a state in which a document feed tray of the automatic document feeder illustrated in FIG. 1 is opened (lifted).

Explanation of symbols

10 Automatic Document Feeder 11 Document Feed Tray (Document Placement Section)
12 Document Feeding Mechanism 21 Document Feeding Roller 21a Roller Housing 21b Pickup Roller 41 Protective Cover Member 51 Projection

Claims (4)

A document placement section on which a document is placed;
A document feeding mechanism having a sheet feeding roller for feeding the document to a document reading position;
A protective cover member that covers and covers the document feeding mechanism by providing an opening for receiving a document from the document placement unit;
An automatic document feeder according to claim 1, wherein a protrusion is provided on the side of the opening of the protective cover member to protect the paper feed roller in a state in which the protective cover member is closed. The document feeding mechanism has a housing structure;
One end of the protective cover member is rotatably supported by the casing of the document feeding mechanism, the free end side is the opening side, and the free end side opens the protective cover member. The automatic document feeder according to claim 1, wherein the automatic document feeder functions as a part operated by a finger.   3. The automatic document feeder according to claim 2, wherein when the protective cover member is closed, the protruding portion protrudes downward from the other portion of the free end.   4. The automatic document feeder according to claim 3, wherein a width of the protruding portion in the axial direction of the paper feed roller is longer than an axial length of the paper feed roller.

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