JPS61174058A - Paper feeding device - Google Patents

Abstract

PURPOSE:To provide optimum copying speed for a sheet feeder of an image creating device by allowing a plurality of transporters to operate overlapped with one another, wherein the relative position of a sheet retaining member can be changed in the operating direction of transporters. CONSTITUTION:To transport sheets 19 of A3 format by a sheet feeder 10, the relative positions of two sets of roller chains 14 are changed by a clutch 17 to allow grippers 18 of the two chains to approach each other, and now the leading edge of a sheet 19 is grasped by that of the grippers 18 which is situated at the roller chain 14 on the lagging side seen in the sheet traveling direction, i.e. on the outer side. To transport sheets 20 of A4 format, on the other hand, the arrangement is so altered that diver 15 of the inner roller chain 14 is situated approx. in the middle of two divers 16 installed on the outer roller chain 14, and the spacing of these divers 15, 16 is set to A4 format. Then the two roller chains 14 rotate in linkage, and their grippers 18 transport the sheet 20. This will eliminate unused spaces on the sheet path to result in enhancement of the copying efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a paper feeding device of an image forming apparatus that obtains a final image quality by overlapping and transferring images onto paper a plurality of times.

(Prior Art) Conventionally, for example, a color electrophotographic copying machine prints originals in red (
R), green (G), and blue (B), and each color separation image obtained is treated with a developing agent (
Cyan (C), magenta (M).

Yellow (Y)), and the developed images are sequentially superimposed and transferred onto paper to form a color image. The quality of the images formed by this overlapping transfer depends on the positional accuracy (
(Presence or absence of registration deviation) K is greatly influenced.

In order to ensure high positional accuracy, the prior art mechanically increases the accuracy using, for example, a device as shown in FIG. 5 or 6.

That is, in FIG. 5, a plurality of self-forming devices (1) (three in this figure) are arranged in series, and in order to sequentially overlap and transfer each image formed by each self-forming device, Paper (2
) is gripped and conveyed to the bottom of each image forming device (1).The path of grits & (3) is formed in a circular chain (4). A notched drum (
8) It is a multiformed type.

(Problems to be Solved by the Invention) However, in these conventional devices, the circumferential length of the chain and notched drum is determined by the maximum paper size used, and in order to improve copying efficiency, multiple The spacing between the grits 19 of the device provided with the grits is similarly set according to the maximum paper size used. Therefore, when copying with these devices using paper smaller than the maximum paper size, the time required for one copy cycle is the same as when using the maximum paper size, resulting in wasted work time. For example, in a device that can transport AM size and A4 size paper, the mutual spacing between the plurality of grits is set to match the large A3 size paper, and the small size During A4 size copying, after one gripper passes through the paper gripping point, it takes an additional time equivalent to A3 size until the next gripper is brought to this gripping point.

For this reason.

The copying speed is approximately 1/2 that of an A4 size printer.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper feeding device for an image forming apparatus which eliminates the drawbacks of the prior art described above and which allows optimum copying efficiency to be obtained at all times regardless of paper size.

(Means for Solving the Problems) That is, the above object of the present invention is to provide a paper feeding device comprising a conveying body to which a plurality of paper holding members are fixedly installed, in which the plurality of conveyance bodies are superimposed on each other. This is achieved by a paper feeding device characterized in that the relative position of the paper holding member is variable in the direction of movement of the conveying body.

(Example) Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram explaining a paper feeding device according to an embodiment of the present invention, FIG. 1(a) is a plan view, and FIG.
A-A arrow view of a). In addition, in this example, A6
A case will be described in which a sheet of A4 size is conveyed by a conveyor made of a roller chain.

In addition, in the apparatus of this embodiment, a paper holding member that grips the leading edge of the paper is formed with ties and grippers described later, and although not shown in FIG. Multiple pieces are arranged along the direction.

In FIG. 1, the paper feeding device (10) according to the present invention includes a set of a drive shaft (11) and a driven shaft (12) arranged side by side with a predetermined interval, and the drive shaft (11) and the driven shaft (12). Driven shaft (12)
The roller chain is generally composed of four sprockets (1) each pivoted at opposing positions, and four roller chains (14) that are meshed with these sprockets (13) and rotate. The roller chain (14)
The two chains arranged on the inside and the two chains arranged on the outside are connected to each other by a plurality of tie bars (15, 16) attached to the chains (14), respectively, forming a paired structure. The spacing between the two connected roller chains (14) is the same as the width of A3 size paper (
(the length in the direction perpendicular to the conveyance direction). Moreover, these two sets of roller chains (14) each have a drive shaft (1
(1) side sprockets) (one of which is rotatably mounted on the shaft through a clutch (17), and a plurality of tights fixed to these roller chains (14)) The relative positions of (15, 16) are freely variable in the moving direction of the roller chain (14).

In addition, the two sets of roller chains (14) are provided with adjacent ties 19 and 19 that are slightly longer so that they substantially match the length of A-size paper (length in the conveyance direction).

Furthermore, each of the tights (15, 16) is provided with grits 08) on its outer surface for gripping the leading edge of the paper.

When conveying an A6 size paper (19) by the paper feeding device (10) provided in this way, the two sets of roller chains (14) are connected to the clutch (1) as shown in FIG.
7) whose relative position is changed by Glitz J? (18) are provided substantially close to each other. The -A3 size paper (19) is held by the gripper (1a) located on the delayed side in the paper movement direction (outward r3 in this figure).
．． The leading edge of the paper is gripped by a gripper provided in the z-a-n and is conveyed. At this time, the inner side Ronilla Doo Aets does not hold the paper, and the outer mouth? ? - In cooperation with Unaboots, the rotating mano becomes non-rotating.

Next, when A4 size paper (20) is transported, two sets of rows 9. f age (
14) can be changed relative to each other.

That is, the outer t! 7ffi9- is varied so that the tie bar (15) of the inner c3-rachie:>H4) is placed approximately in the center position of the two tights (i6, 16) provided on the age (14), Tie A-(15,
16) The interval is set to the length of A4 size paper. Once the relative positions of the two sets of 05Utoeta (14, 14) have been set in this way, the next step is Ryoro-? Now'ri'-n (14,1
4) starts to rotate in cooperation, and both [! lJ-La+Coutts (
14, 14) Gritsu' (18) K Yoshi paper (20)
transport. Therefore, there is no empty space on the path of the two former consorts, improving copying efficiency.

In the above-described embodiment, a roller chain is used as the rotating body, but other chain members may also be used. Furthermore, a belt member can be used in place of the chain member.

FIG. 4 shows another embodiment of the invention.

This embodiment device has two notched drums (21, 22) loosely fitted as rotating bodies for conveying paper.

These notched drums (21, 22) each have a pair of frames (
23) is one tie bar with grits A (24)
(25), and the length of the paper approximately corresponds to the maximum paper size used by each station, for example, A3 size paper. In addition, two notched drums (2
1 and 22) are each rotatably provided on their own so that their relative positions in the circumferential direction can be varied.

When A6 size paper is transported, the tights (25, 25) are close to each other, and when A4 size paper is transported, each tights (25, 25) are close to each other.
, 25) are set at opposing positions on the circumferential surface of the drum, and the paper is conveyed by both drums (2L22).

(Effects of the Invention) As described above, according to the paper feeding device of the present invention, a plurality of rotating bodies moving on the same path are provided.

By changing the relative positions of these rotating bodies according to the paper size, it is possible to eliminate wasted space on the path of the rotating bodies and carry out conveyance that always provides the optimum copying speed.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a paper feeding device according to an embodiment of the present invention, FIG. 1(a) is a plan view thereof, and FIG. FIG. 2 is a diagram illustrating the conveyance of A6 size paper using the apparatus shown in FIG. 1, FIG. 3 is a diagram similarly illustrating the conveyance of A4 size paper, and FIG. A perspective view of a paper feeding device according to an embodiment, and FIGS. 5 and 6 are views for explaining a conventional example. Reference numeral 10 in the figure... paper feed device, 16... sprocket 14... el-ra f-ane, 15
．． 16.25...Tights-17...
Clutch, 18.24... Grits/zo 21
．． 22. River... Notched drum wi1 Figure 2 fM Figure 4 Figure 5 Practice 6 @

Claims (1)

[Claims] 1) In a paper feeding device consisting of a conveying body to which a plurality of paper holding members are fixedly attached, the plurality of conveyance bodies move in a manner that overlaps each other, and the relative positions of the paper holding members are is variable in the moving direction of the conveying body. 2) The paper feeding device according to claim 1, wherein the conveying body is provided by an annular chain member. 3) The paper feeding device according to claim 1, wherein the conveying body is provided by an annular belt member. 4) The paper feeding device according to claim 1, wherein the conveying body is provided by a notched drum.