JPH03133858A - Sheet conveying device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of choking with sheet and production of wrinkles because of the side end part of a sheet being difficult to separate away from a roller body by a method wherein the central lines of a pair of roller bodies brought into contact with the side end parts on both sides of a specified sheet are positioned inside the end parts on both sides of the specified sheet. CONSTITUTION:A pair of roller bodies 21 and 22 are arranged so that central lines C of the roller bodies 21 and 22 making contact with the end parts on both sides of a specified sheet are positioned inside end parts P1 on both sides of a specified sheet P. Therefore, the side end parts P1 of the sheet P are difficult to separate away from the roller bodies 21 and 22. Besides, since a notch apex 11a of a triangular shape formed on the downstream side of each of through-holes 11 and 12 is positioned outside the side end part P1 of the specified sheet P, there is no fear of the corner of the sheet P being hooked to an oblique edge positioned outside the apex 11a and extending from the outside to the inside in the direction of the width of the sheet P.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a paper feed device in an image forming apparatus such as a copying machine, and a paper conveyance device applied to an automatic document conveyance device installed in the image forming apparatus. It is related to the device.

<Prior Art> Conventionally, as shown in FIG. 6, the above-mentioned paper conveyance device has a plurality of roller bodies 91 on a rotating shaft 90 of a book in order to accommodate paper of multiple sizes. Arranged rollers 92
and a paper guide plate 93, and a portion of each roller body 91... is formed through a through hole 94... provided in the paper guide plate 93 and corresponding to each of the roller bodies 91... It is arranged and configured to protrude from the paper guide surface 95 of the guide plate 93.

In addition, in order to prevent the leading edge of the paper from getting caught in the downstream edge 96 of the through holes 94, the edge 96 is cut out in a triangular shape as shown in the figure.
Alternatively, as shown in FIG. 8 (Tayama), the above-mentioned edge 96 is bent inward.In particular, the manufacturing process can be simplified by eliminating the need for a bending process, so the former triangular shape Notches are commonly used.

<Problems to be Solved by the Invention> However, in the above-mentioned paper conveyance device, in order to correct the paper being conveyed so that it is not slanted, and when the width detection switch detects the side edge of the paper, the paper may escape. In order to prevent this and ensure that the side edges of the paper are detected,
It is necessary to arrange the roller body 91 so as to correspond to the side edge of the paper as much as possible, and when the roller body 91 is arranged so as to contact the side edge of the paper, the side edge of the paper and the roller body 91 It was difficult to set the positional relationship between the two and the following problems occurred.

That is, if the center line C of the roller body 91 is outside the side edge P1 of the paper P, as shown by the dashed line in FIG. body 9
1, which may cause a paper jam (paper jam) or cause the paper P to wrinkle.

On the other hand, as shown in FIG. 7 (b+), when the center line C of the roller body 91 is inside the side edge P1 of the paper P,
A corner P2 of the paper P is caught on a beveled edge 96b extending from the outside in the width direction of the paper toward the inside, which is located outside the apex 96a of the edge 96' cut out in a triangular shape on the downstream side of the through hole 94. There have been problems such as paper jams, folding of the corner P2, and so-called edge folding.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a paper transport device that can reliably transport paper without the risk of paper jams, edge folds, wrinkles, etc.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the paper conveying device of the present invention has a paper conveyance device in which, among the roller bodies, a pair of roller bodies that abut the image side edge of the paper are aligned with their respective center lines. are arranged on the rotating shaft inwardly from the positions of both ends of the paper, and the triangular notches of the through holes corresponding to the pair of roller bodies are located at the respective vertices. It is characterized in that it is formed in a state in which it is positioned outside both side edges of the paper.

Function> In the paper conveying device of the present invention having the above configuration, the center line of the pair of roller bodies that abuts on both side edges of the specific paper is located inside than the both side edges of the specific paper. , Since the roller body is arranged, the side edge of the paper is difficult to come off from the roller body. Moreover, since the apex of the triangular notch formed on the downstream side of the through hole is located outside the side edge of the paper, the corner of the paper is There is no risk of getting caught on the beveled edge going from the outside to the inside.

<Example> Below, a paper conveying device of the present invention will be described with reference to drawings showing examples.

As shown in FIG. 5, the paper conveyance device of this embodiment, in an automatic document conveyance device A installed in an image forming apparatus B such as a copying machine, feeds documents placed on a document tray A1 one by one. This is applied to the part of the registration roller that is used to carry documents into the device, and is arranged so as to be inclined from the top to the bottom from the document entry port A2 toward the inside of the device, as shown in Figures 1 to 4. The document guide plate 1 includes a document guide plate 1, and a transport roller 2, which is disposed above the document guide plate 1 and serves as the upper roller of a pair of registration rollers.

The conveying roller 2 includes a rotating shaft 20 disposed orthogonally to the conveying direction of the document, a roller body 21° 21 arranged on the rotating shaft 20 that is compatible with large documents, and a roller body 21 that is compatible with small documents. roller bodies 22° 22, each roller body 21,
22 . . . are partially protruded downward from the document guide surface 10 , which is the lower surface of the document guide plate 1 , through through holes 11 , 12 , . . . provided in the document guide plate 1 .

Of the roller bodies 21, 22..., the roller bodies 21, 21 at both ends are attached to both ends P1 of the large document P.
, Pl, so that each center line C is located inside the side edge P1 of the large document P, as shown by the dashed line in FIGS. 1 and 2. The through holes 11, 11 corresponding to the roller bodies 21, 21 at both ends have triangular notches formed on the downstream side thereof, and the respective apexes 11a is positioned outside the side edge P1 of the document P.

When the original P is conveyed in the direction shown by the arrow in FIG. 2, the original P
The corner P2 of the triangular notch is guided by the beveled edge 11c inside of the apex 11a without being caught by the beveled edge 11b of the triangular cutout, and is conveyed smoothly.

The automatic document feeder into which the paper feeder is incorporated is comprised of the following members.

That is, as shown in FIG. 4, the paper conveyance device
Sequentially from the document entrance A2 side, a feed roller 3 that feeds out the document set on the document tray A1;
a support arm 5 that supports the document, and a paper feed roller 4 that feeds the document sent out by the delivery roller 3 to the conveyance roller 2.
, a reverse feed roller 6 that pairs with the paper feed roller 4, a support arm push-up means 8 that pushes up the support arm 5, the conveyance roller 2, and a driven roller 9 that pairs with the conveyance roller 2. The document fed from the paper feed section A3 is conveyed to a predetermined position on the document placement plate B1 of the image forming apparatus B, and the exposed document is removed from the apparatus. It also includes a document conveyance belt A4 for ejecting documents.

As shown in FIGS. 1 and 3, the paper feed roller 4 includes a rotating shaft 41 driven by a motor, and a plurality of roller bodies provided on the rotating shaft 41 at predetermined intervals in the axial direction. 42..., and the drive of the motor is controlled so that it rotates once every time one document is sent out. Further, a notch 42a is provided in a part of the outer periphery of the roller body 42, and after feeding the document, the paper feed roller 4 stops with the notch 42a facing downward, and the pair is separated. A gap is formed between the reverse feed roller 6 and the reverse feed roller 6, so as not to interfere with the document conveyance by the conveyance roller 2 and the document conveyance belt A4.

The reverse feed roller 6 is used to prevent more than one original from being fed, and is rotated in the opposite direction when the original is transported.

The delivery roller 3 is connected to a shaft 31 that rotates following the rotation shaft 41 via a timing belt 7 (see FIGS. 1 and 3), and a shaft 31 that is mounted on the shaft 31 at a predetermined interval in the axial direction. A roller body 32 is provided.

The support arm 5 has a base end rotatably supported by the rotating shaft 41 of the paper feed roller 4, and a shaft 31 of the delivery roller 3 rotatably fitted into a hole 51 provided at the distal end. By rotating around the rotation shaft 41, the feed roller 3 attached to the tip can be moved to two positions: a lower position where it comes into contact with the originals set on the original tray A1, and an upper position where it moves away from the originals. It is possible to move between.

The support arm push-up means 8 includes a rotating shaft 81 and a protrusion 5 at the proximal end of the supporting arm 5.
2, and a push-up piece 82 that abuts on.

To explain the operation of each of the above parts, first, the rotation shaft 81 of the support arm push-up means 8 rotates in the direction shown by the arrow in FIG. is released, the support arm 5 rotates downward,
The feeding roller 3 at the tip comes into contact with the original on the original tray A1. Next, the delivery roller 3 rotates to send out the top document, and the paper feed roller 4 feeds the top document to the transport roller 2, and the transport roller 2 and the document transport belt A4 disposed on the downstream side. The document is transported to a predetermined position on the document placement plate B1. After the document is conveyed, the rotation shaft 81 of the support arm push-up means 8 further rotates, and the push-up piece 82 engages with the protrusion 52 of the support arm 5.
is pushed upward to separate the feed roller 3 from the document.

In the figure, S1 is a document set detector that detects when a document is set in document tray A1, A5 is a restraining member that allows the document to be sent out only when necessary, and S2 is a device that detects the leading edge and end of the document. document length detector, which measures the length of the document;
S3 is a document width detector that measures the width of the document.

The document length detector S2 and the document width detector S3 are normally arranged at the same distance from the document entrance A1 in the document transport direction, and the leading edge of the document is detected simultaneously by the rain detectors S2 and S3. , is programmed to measure the width of the sheet and to start measuring the document length by the document length detector S2.

However, if the document is conveyed obliquely and the document width detector S3 is delayed in detecting the document width when the document length detector S2 starts measuring the document length, there is a possibility that the document width cannot be measured correctly. Therefore, so that the leading edge of the document is detected by the document width detector S3 before the document length detector S2, the document width detector S3 is set at the document entrance A1 rather than the document length detector S2. It is preferable to place them nearby.

Note that the paper conveyance device according to the present invention is not limited to the above embodiments.

For example, in the above embodiment (1), the roller bodies 21 which come into contact with the side edges I of the large sheet of paper at both ends of the conveyance roller 2.
21 and the apexes 11a, lla of the triangular notches of the through holes 11.11 corresponding to the roller bodies 21, 21.
The positional force of the present invention was that of the inner roller body 22.22 force (of the inner roller body 22). The structure of the present invention can also be applied to the positions of the apexes of the triangular cutouts of the bodies 22, 22 and the corresponding through holes 12.12.

In addition, in the above embodiment, the force exerted by the conveyance roller 2 (the four roller bodies 21, 22, etc.) may be 3 or 5 or more. Also good.

In the above embodiment, the configuration power of the present invention is applied to the registration rollers of the automatic document conveyance device, and the configuration of the paper conveyance device of the present invention is applied to the registration rollers of the automatic document conveyance device. It can also be applied to the paper feeding roller of the paper cassette/gutter, the paper refeeding roller of the intermediate tray, or (first of all, other conveyance rollers) in the forming apparatus.

In addition, various design changes can be made without changing the gist of the invention.

<Effects of the Invention> The paper conveying device of the present invention is configured as described above, and the center line of the roller body of 1 sentence 1 that comes into contact with both side edges of the specific paper is closer than the both side edges of the specific paper. Since the roller body is located on the inside, the side edge of the paper is difficult to come off the roller body force 1, and paper jams, wrinkles, etc. are prevented from occurring. The apex of the triangular notch formed on the downstream side of the through hole corresponding to % is located outside the side edge of the paper.
Therefore, there is no risk of the corner of the paper getting caught on the beveled edge outside the apex, and it is guided by the beveled edge inward from the apex and is conveyed smoothly, preventing paper jams, edge folds, etc. is prevented.

[Brief explanation of the drawing]

FIG. 1 is a bottom view showing the registration rollers and their surrounding parts of an automatic document feeder to which the paper feeder of the present invention is applied;
Figure 2 is an enlarged bottom view of the main parts of the registration roller.
FIG. 3 is a perspective view showing the entire automatic document feeder, FIG. 4 is a sectional view showing the internal structure of the main parts of the automatic document feeder, and FIG. FIG. 6 is a bottom view showing the registration rollers of an automatic document feeder having the configuration of a conventional paper transport device; FIG. 7 (al city) is a perspective view showing the registration rollers installed in an image forming apparatus; An enlarged bottom view of the main parts in Figure 8 (
a) is a sectional view showing another example of a conventional paper conveying device;
FIG. 3 is a bottom view of the above-mentioned another paper conveyance device. DESCRIPTION OF SYMBOLS 1... Guide plate, 1 11.12... Through hole, 11 2... Conveyance roller, 2 21.22... Roller body, P... Paper, P 0... Guide surface, a ... Vertex, 0... Rotation axis, C... Center line, 1... Side end. ■... Guide plate 11... Through hole 11a... Vertex 2... Conveying roller 20... Rotating shaft 21... Roller body C... Center line P... Paper Pl... Side edge part Fig. 5 (a) 6 4 0 9] C...Center line P...Paper Pl...Side edge part

Claims (1)

[Scope of Claims] 1. A conveyance roller in which a plurality of roller bodies are arranged on a rotating shaft, and a guide plate for guiding paper, the guide plate having a triangular shape on the downstream side in the paper conveyance direction. In a paper conveying device in which a part of each roller body protrudes from a guide surface of a guide plate through a through hole cut out in the shape of are arranged on the rotating shaft with their respective center lines located inside the positions of both ends of the paper, and triangular notches in the through holes corresponding to the pair of roller bodies are provided. A paper conveyance device characterized in that the vertices of the paper are located outside both ends of the paper.