JPS6347242A - Sheet conveying device - Google Patents

Abstract

PURPOSE:To prevent improper feeding of a sheet by making the elastic material of the surface layer part harder than the elastic material of the center part of a conveying roller which is opposite to a sheet handling table, and making the friction coefficient of said roller larger than that of said sheet handling table. CONSTITUTION:A center part elastic material 56 is provided around the core metal 53 of a conveying roller 17 and, further, a surface layer part elastic material 52 is provided on its outside and the surface layer part elastic material 52 is made harder than the center part elastic material 56. Further, the friction coefficient of the surface of the surface part elastic material 52 is made larger than that of a sheet handling table 14 in its vicinity. A sheet which is discharged out of the sheet handling table 14 by means of a conveying belt 13 is fed by means of the conveying roller 17. Thereby, a sheet can be prevented from slackening, enabling the accurate feeding of a sheet while preventing the disturbance of a picture image.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a sheet conveying device that conveys sheets on a sheet processing table.

A sheet processing table is a table on which a sheet is placed in order to perform predetermined processing on the sheet. For example, contact glass in copying machines falls under this category. In this case, image exposure work as a predetermined process is performed on the sheet placed on the contact glass.

As a moxibustion sheet conveying device, one shown in FIG. 6 is conventionally known. This conventional device conveys a sheet, for example, an original 73, on a contact glass 72 using rubber rollers 71, 71, and attempts to read an image of the original 73 through the contact glass 72 during the conveyance.

In this conventional sheet conveying device, the rubber roller 71
．． Since the sheet is held down by the presser 71, the presser foot pressure is not sufficient, and the presser foot pressure is unstable, and as a result, sheet feeding errors are likely to occur.

Furthermore, since sufficient presser foot pressure cannot be maintained, the so-called nip width is narrow, which also tends to cause poor feeding. When a sheet feeding failure occurs, the processing performed on the sheet, such as image exposure operation in a copying process, becomes inaccurate. Furthermore, sponge rollers are easily soiled and, as a result, sheet stains are more likely to occur.

OBJECTS In view of the above points, an object of the present invention is to provide a sheet conveying device that can improve sheet feeding defects and accurately process sheets.

The purpose of the above is to create an elastic member that is placed opposite a sheet processing table for contact glass, etc., has an elastic member in the center, and has a surface layer harder than the center and a higher coefficient of friction than the sheet processing table. This is achieved by providing a conveyance roller that is .

Hereinafter, the present invention will be explained based on examples.

In FIG. 1, sheets, for example, originals Di, D2, . D3 is loaded. A sheet feeding means 50 is connected to the sheet placing section 1 .

The sheet feeding means 50 includes a circular roller 2 having a circular cross section with a part of its outer periphery cut off, a push plate 7 made of a flexible material, and a separating roller 3 rotating counterclockwise. ,
It has a separating member 4 that is pressed against the separating roller 3 with appropriate pressure by a spring 5, pull-out rollers 10 and 11, and guide plates 8 and 9 that connect these members to form a sheet conveyance path. .

At the exits of the guide plates 8 and 9, the 10E of the sheet conveying belt 13 is placed facing the contact glass 14 as a sheet processing table. The sheet conveying belt 13 is supported by two rollers 15 and 16, and rotates in both directions, as shown in A and 2, by the rotation of at least one of the rollers.

A recycling feeding means 51 is provided on the 10E side of the sheet conveying belt 13. This recycling feeding means 5
1 includes a conveyance roller 17, auxiliary rollers 21 and 22, paper discharge rollers 27 and 28, and guide plates 23 and 24 that connect these members to form a sheet conveyance path.

A reversing feeding means 52 is provided at the 20F, which is the sheet entrance/exit on the opposite side to the 10E of the sheet conveyance belt 13. This reversing feeding means 52 includes a reversing roller 31 that rotates counterclockwise, a sheet peeling claw 29, and a switching claw 3.
0, discharge rollers 33, 34, etc. 32 is a cover, and 36 is a guide plate.

The contact glass 14 is a transparent glass, and an exposure optical system 60 and a photoreceptor 61 are arranged below it. The exposure optical system 60 performs a predetermined process, that is, an image exposure action, on the original placed on the contact glass 14, and includes a lamp 62 and four mirrors 63.
, 64, 65, 66, and a lens 67. When there is an original on the contact glass 14, the light emitted from the lamp 62 is reflected by the original, and the reflected light is irradiated onto the photoreceptor 61 as a light image via mirrors 63 to 66 and a lens 67. By irradiating this light image, an electrostatic latent image is formed on the photoreceptor 61, and a well-known copying process is performed on this latent image.

In this embodiment, the exposure optical system 6o has the following three types depending on one selection.
Two modes of operation can be adopted. One is to fix the exposure optical system 60 in the illustrated state and illuminate the document moving on the contact glass 14 with the lamp 62 at position (3) (fixed mode). The other one is to scan and move the lamp 62, mirrors 63 to 66, and lens 67 in the Y-Y direction to expose and scan the document located between position 2 and position W (large movement mode). The remaining one is
Position 1 from position Z corresponding to the left end of the sheet conveyance belt 13
It scans and moves a small range up to w (small movement mode).

The outline of the configuration has been described above, and its operation will be described below.

First, originals DI, D2. D3 is placed. The image surface is facing upward. The lower several sheets of these originals are sent out by the omitted circle roller 2, and the lowest one of these documents, that is, D3, is sent out by the separation roller 3 and the separation member 4.
Another manuscript D2. The sheet is separated from Di and sent to pull-out rollers 10 and 11, and further sent to sheet conveying belt 13 from No. 10E. At this time, sheet conveyor belt 1
3 is rotating in the A direction (counterclockwise), and therefore,
The document D3 is conveyed to the right over the contact glass 14 by the sheet conveying belt 13 (FIG. 2P).

When the trailing edge of the document is detected by the sensor 37 and a predetermined period of time has elapsed, the rotational direction of the sheet conveying belt 13 is reversed to the clockwise direction (direction B).
This causes the document to move toward the conveyance rollers 17. Conveyance roller 1
The document D3 transported by the sheet transport belt 1
10E of the sheet feeding means 50, and is further prevented from floating by the floating prevention piece 38 formed by bending the guide plate 9 of the sheet feeding means 50.
Sent to 7. At this time, the conveyance roller 17 is rotating clockwise, so the document D3 is transferred to the contact glass 14.
from there to the guide plates 23 and 24 (Fig. 2C)
.

At this time, the exposure optical system 60 is placed in the fixed mode. Therefore, the guide plates 23, 24 are moved by the conveyor roller 17.
The image of the document D3 being conveyed in
exposed to light. The original document D3 on which the exposure work has been completed is directly ejected to the sheet d section 1 by the ejection rollers 27 and 28.

Since the original D3 is reversed while being conveyed along the guide plates 23 and 24, the image surface of the ejected original D3 faces upward. This is the same state as the first draft D3 when it was first set (Fig. 2H).

When the copying work for the original D3 is completed, the copying work for the original D2. A similar copying operation is performed for Di. When the copying of the original document D1, which is the topmost sheet, is completed and the document D1 is discharged onto the sheet stacking section 1 by the paper discharge rollers 27, 28, the documents DI, D2, . The loading status of D3 is exactly the same as the original loading status, so the original
1, it becomes possible to copy the document D3 again.

In this way, recycling automatic paper feeding is achieved in which a plurality of originals are circulated one by one and repeatedly copied.

In this embodiment, as shown in FIG. 3, the conveyance roller 17 has a cylindrical sponge-like elastic member 56 fixed to a metal core 53 (for example, 5 us 41.6 mm).
It is made by covering the surface layer of 6 with an elastic tube 52. The elastic tube 52 in the surface layer is made of a material that is harder than the sponge-like elastic member 56 in the center and has a higher coefficient of friction than the contact glass 14 that is the sheet processing table, such as E PDM processed with resin. The one that has been given is used. Especially the coefficient of friction is μ=0.5~0
．． About 9 is good. Since the transport roller 17 is illuminated by the lamp 62, the elastic member 52, which is the surface layer thereof,
A white one is better.

Since the conveyance roller 17 is made of the elastic member 56 which is soft in the center and the elastic member 52 which is slightly hard in the surface layer, the contact glass 14 is moved as shown in FIG.
A sufficient nip width WD can be obtained between the two, and the presser foot pressure can also be made uniform. Therefore, the conveyance of the document is stabilized, and image exposure by the exposure optical system 60 is stabilized. As a result, the photoreceptor 6
A uniform and high-quality latent image is created on the surface of the image.

In addition, the 37th code|symbol 54 is a bearing of the core metal 53.

The above explanation is based on the apparatus shown in FIG.
3 is for automatic recycle feeding, but in addition to the recycle automatic feeding mode, this device has two different feeding modes: an automatic feeding mode for large-sized originals and an automatic feeding mode for small-sized originals. You can take it.

Include-size original automatic feeding mode This mode allows dog-sized originals (e.g., A3, 84 or larger) to be fed in sheets instead of being circulated (recycled) between the sheet placement section 1 and the contact glass 14 as described above. A plurality of originals placed on the placement section 1 are sequentially fed one by one onto the contact glass 14, and then automatically ejected to a predetermined ejection position and into pages.

In this mode, the lowest document D3 is separated from the other documents Di and D2 by the separation roller 3.

Thereafter, the process until reaching the position V opposite the conveyance roller 17 is the same as in the above-mentioned recycle feeding mode.

In this mode, after that, the conveyance roller 17 and the sheet 1-
11, the rotation of the feed belt 13 stops, and the document stops at this position on the contact glass 14.

The exposure optical system 60 is conditionally set to adopt the above-mentioned large movement mode, and exposes and scans the document stopped on the contact glass 14 from position (2) to position (W). When the lamp 62 (FIG. 1) returns to position V and the exposure scan is completed, the conveyance roller 17 and the sheet conveyance belt 13 both begin to rotate counterclockwise, and the document D3 is placed on the contact glass 1.
4 Move to the right on the top. Then, after being reversed by the first reversing roller 31, the document is discharged onto the document stacker 35 by the discharge rollers 33 and 34.

In this way, in this mode, the original is placed on the contact glass 14.
It is fixed at the top and the exposure optical system 60 is moved to perform exposure.

Small-sized original automatic feeding mode This mode is the same as the large-sized original automatic feeding mode described above, but the difference is that small-sized originals are fed instead of large-sized originals. It is.

In this mode, the exposure optical system 60 takes the aforementioned small movement mode. In other words, the exposure scan is about mW from position Z.
It is carried out within the range of

The lowermost document D3 is sent to the seal conveyor belt 13 via the separation roller 3 in the same manner as in the large-size document feeding mode. In this mode, the document D3 then stops at that position, and the conveyance roller 17 does not return to the position (2). In this state, the exposure optical system 60 scans and moves from position Z to position W to perform image exposure work.

In this case, since the M document is small in size, sufficient exposure can be performed even in the short distance from position 2 to position W. Also, by making the process shorter, cost savings and shorter work times can be achieved.

Effects As described above, according to the present invention, since the conveying roller is constructed by dividing the hard and soft elastic members into a center portion and a surface layer portion, sheet feeding defects can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of one embodiment, FIG. 2 is a schematic diagram showing how the sheet is conveyed, FIG. 3 is a partially cutaway perspective view of the conveying roller, and FIG. 4 is a side sectional view of the conveying roller. FIG. 5 is a schematic diagram showing another sheet conveyance situation, and FIG. 6 is a side view of the conventional example. 14... Sheet processing table (contact glass) 17...
- Conveyance rollers D1 to D3... Sheet (original) 52... Front elastic member 56... Center elastic member

Claims (1)

[Claims] In a sheet conveying device that conveys sheets on a sheet processing table, it is arranged opposite to the sheet processing table, the center part is an elastic member, and the surface layer is harder than the center part and has an elastic material with a higher coefficient of friction than the sheet processing table. A sheet conveyance device characterized by having a conveyance roller as a member.