JPS61162435A - Cut sheet supply device - Google Patents

Abstract

PURPOSE:To make the press-contact forces of feed rollers acting upon on the left and right sides of a paper sheet to be used, substantialy equal to each other, by shifting the gravitational center of the feed roller to a substantially center position in the lateral direction of the sheet with the use of a weight in accordance with the size of paper sheets. CONSTITUTION:A shaft 3 is rotated for every paper feed, and this rotation is transmitted to a feed roller 6. The uppermost paper sheet is separated from the paper sheets subsequent to the second one, since both left and right corners of the uppermost one come off from separating pawls 2, 2 due to the feed-out force provided by the rotation of the roller 6. The thus separated uppermost paper sheet is fed into between guide plates. At this time, a movable weight 10 is slid to left and right along a guide rod 11 to adjust the slide position in accordance with the size of the sheets so that the gravitational center of the feed roller is shifted to a substantially middle point position W' or W'' of a paper sheet to be used in the lateral direction. With this arrangement the press contact forces on the left and right sides of a paper sheet are substantially equal to each other for vaious size paper sheets, and therefore, no oblique feed trouble may be caused, thereby it is possible to feed paper sheets smoothly one by one.

Description

Detailed Description of the Invention A. Purpose of the Invention [Industrial Field of Application] The present invention provides a method for cutting sheets by pressing a feeding roller onto the top surface of stacked cut sheets (sheets, hereinafter referred to as paper). The present invention relates to a cut sheet feeding device that separates and feeds sheets one by one.

[Conventional technology]

The above-mentioned feeding devices include cassette type, deck type and g! il
It is used as a paper feeding device for paper such as paper, electrostatic recording paper, electrofax paper, etc.

In the cassette type, paper is loaded and stored in a paper storage cassette with a built-in middle bottom plate that is supported by a push-up spring to freely swing up and down, and the cassette is loaded into the feeding device, and the paper is fed to the top surface of the paper stored in the cassette. The stacked sheets are fed out one by one from the top one by one by pressure contact of the feeding roller on the feeding device side. In response to the decrease in the weight of the stored paper as the paper is sequentially fed out and consumed, the middle bottom plate, that is, the stored paper, is automatically successively lifted up by a push-up spring, and the weight of the stored paper is increased regardless of the decrease in paper consumption. The top position level is always maintained substantially integrally at a predetermined reference position level. However, the relationship between the weight of the stacked paper and the push-up spring force that allows the upper surface level of the stacked paper to be maintained at a constant level is not wide, and the paper storage capacity of the cassette is limited to about 250 to 500 sheets. be done.

In the deck type, paper is loaded on a deck plate that is driven vertically by an elevator mechanism powered by a motor, etc. (or a container loaded with paper is stored), and a feeding roller is pressed against the top surface of the stored paper. It feeds and feeds sheets one by one starting from the top of the stack. Then, a level sensor detects a gradual decrease in the level of the top surface of the stacked paper as the paper is sequentially fed out and consumed, and the deck plate is sequentially moved upward each time it is detected that the level has fallen to the allowable lower limit level. , the top surface position level of the stacked paper is always maintained within a predetermined reference position level range. This deck type can store a larger amount of paper at one time than the cassette type, and can continuously perform a large amount of copying without interrupting work to replenish paper midway through.

The paper feed roller is normally held upward from the top surface of the stacked paper in a non-contact manner, and is brought into downward dynamic pressure contact with the top surface of the stacked paper each time paper is fed.In this case, the roller is always rotated in the paper feeding direction, or There are two types of rollers: one in which the roller is pressed against the top surface of the stacked sheets and then rotated, and the other in which the roller is always pressed against the upper surface of the stacked sheets and the roller is driven to rotate in the sheet feeding direction each time the sheets are fed.

[Problem that the invention seeks to solve]

By the way, the conventional paper feeding device of the above type,
When feeding small size paper, the skew feeding phenomenon was likely to occur.

The smaller the paper size, the more the paper will move in the left and right direction (perpendicular to the paper feeding direction) with respect to the center of gravity of the feeding roller.
This is because the position of the intermediate point of the paper is significantly shifted, and as a result, the pressure contact force of the feeding roller acting on the left and right sides of the paper becomes uneven.

The present invention aims to solve this problem.

Summary: Structure of the Invention [Means for Solving the Problems] The present invention provides a cut sheet feeding device that separates and feeds stacked cut sheets one by one by bringing a feeding roller into pressure contact with the upper surface of the stacked cut sheets. The cut sheet feeding device is characterized in that it is equipped with a movable weight that shifts the center of gravity of the feeding roller in a direction substantially perpendicular to the sheet feeding direction.

[For production]

That is, depending on the size of the paper loaded and stored in the cassette or deck plate, a movable weight is used to shift the center of gravity of the feeding roller to approximately the midpoint in the left-right direction of the paper. The feeding roller pressure contact force acting on the right side is approximately equalized. Therefore, with this procedure,
It is possible to smoothly feed sheets of various sizes without the problem of skew feeding due to an imbalance in the pressure contact force of the feeding roller acting on the left and right sides of the sheet.

〔Example〕

The drawings show the main parts of the feeding device of the present invention, with FIG. 1 being a plan view, FIG. 2 being a sectional view, and FIG. 3 being a front view.

P is the paper stacked and stored in the cassette or on the deck plate (both omitted in the figure), la, 1b, and IC are the dimensions of the front and left and right sides of the stacked and stored paper P.
? ++7-f: jl tjl 1 h e 1
r: Separation claws for one sheet of paper are provided at the left and right corners of the front side of the top surface of the paper, respectively. In this example, the left and right regulating plates lb/IC are fixed in place as one side plate 1b as a reference side plate, and the other side 1c is a movable plate that can be positioned to widen or narrow the distance from the fixedly fixed reference side plate 1b according to the paper size used. This is the side plate. 1 and 3 are A4 size sheets, FIG. 4 is a LGL size sheet, and FIG. 5 is a postcard size sheet of paper that is regulated and stored between the fixed side plate 1b and the movable side plate la.

3 is a feeding roller rotation drive shaft, 4 is a rocking plate attached to the shaft so as to be freely rotatable while restricting movement in the axial direction, and 5 is a rotating shaft with restricting movement in the axial direction to the rocking plate. Freely bearing feed roller shafts 6(1)-6(2) are four feed rollers mounted at intervals along the length of the feed roller shaft. Each of the feeding rollers is attached to the shaft 5 via a one-way clutch 6a that allows rotation in the paper feeding direction with respect to the shaft 5.

7 and 8 are timing pulleys fixed to the shafts 3 and 5, 9 is a timing belt suspended around both pulleys, 10
is a weight for shifting the center of gravity of the feeding roller, which is provided on the upper surface of the swing plate 4 so as to be able to slide freely along a guide rod 11 disposed in a direction substantially perpendicular to the sheet feeding direction. Reference numeral 12-12 is a guide plate for the fed paper, and reference numeral 13 is a pair of registration rollers (or a relay conveyance roller).

In the case of the device of this example, the feeding roller 6 can freely swing up and down about the shaft 3 via the swinging plate 5, and its own weight (members 4 to 1)
It is constantly pressed against the upper surface of the loaded paper P with an overall weight of 1). In this case, the paper P used is A4 size (other LTR-
85-84), the four feeding rollers 6(1) to 6(0) are in contact with the top surface of the paper as shown in Figure 1-3.In the case of LGL size, the four feeding rollers 6(1) to 6(0) are in contact with the top surface of the paper as shown in Figure 4. like 6
The feeding roller in (4) is out of the paper surface, and the feeding roller in 6(1) to 6(
The three feeding rollers of 3) are in contact with each other. In the case of postcard size, feeding rollers 6(4) and 6(3) are outside the paper surface, and only two feeding rollers 6(1) and 6(2) are in contact with each other.

The shaft 3 is rotated at a predetermined number of rotations clockwise in FIG. 2 by a drive system (not shown) every time paper is fed.

The rotation of this shaft 3 is as follows: pulley 7 → belt 9 → pulley 8
→ Axis 5 → Feed roller 6 via one-way clutch 6a
This causes the feeding roller 6 to rotate clockwise in FIG. 2, which is the paper feeding direction.

A feeding force acts on the uppermost sheet of the stacked storage sheets P that the feeding roller 6 is in pressure contact with, and the left and right corners of the front side of the uppermost sheet ride up from the lower side of the separating claws 2 and 2 to the upper side. When the paper is removed from the separating claw, it is separated from the next and subsequent sheets. The separated uppermost sheet of paper is fed between the guide plates 12 and 12 by the subsequent rotation of the feed roller 6, and then the feed timing is adjusted by the registration roller pair 13 and conveyed into the machine such as an electrophotographic device. be done.

If the weight 10 for shifting the center of gravity position of the feed roller is not provided, the center of gravity W of the feed roller will always remain at approximately the middle position in the longitudinal direction of the feed roller shaft 5, and the paper used will be at the first position. As shown in Figure 103, in the case of A4 size paper, which is a large size paper, the position approximately corresponds to the middle position in the left-right direction of the paper, and the pressure contact force of the feed roller acting on the left and right sides of the paper is approximately equalized. There is. If the paper being used is LGL size, where 0 is off the paper surface as shown in Fig. 4, the intermediate position of the paper with respect to the center of gravity W of the feeding roller is as shown in Fig. 4. As a result, the paper pressing force of the feed roller 6 (3) that contacts the left side of the paper is greater than that of the feed roller 6 (1) that contacts the right side of the paper, and the pressure between the two An unbalance occurs in the paper pressure contact force.If the paper used is a postcard size that is even smaller and the feed rollers 6 (4) and 6 (3) come off the paper surface as shown in Figure 5, the feed roller The intermediate position of the paper is further shifted to the right with respect to the center of gravity W of ), and the degree of unbalance in the paper pressure contact force between the two becomes even greater than in the case of Fig. 4.Thus, the m of the above-mentioned upper and reverse rollers for the left and right sides of the paper Due to the unbalance of paper flow, skew feeding is likely to occur when small size paper is fed.

Therefore, it can be moved according to the size of the paper used! Slide the weight 10 left and right along the guide rod 13 to adjust the position so that the center of gravity of the feed roller is approximately at the midpoint in the left-right direction of the size paper being used (position W' in Figure 4, position W in Figure 5). Take steps to shift it. As a result, the pressure contact force of the feeding rollers acting on the left and right sides of sheets of various sizes is approximately equalized, so that both sheets can be fed smoothly without any skew feeding troubles.

The weight 10 can be detachably attached to the swing plate 4 using a coin screw, a magnet, etc., and the center of gravity 1w can be shifted by attaching it to an appropriate position on the plate 4 as necessary. It is also possible to use a combination of weights of various weights to increase or decrease the pressing force of the feeding roller against the paper as required.

Of course, the present invention can also be applied to a feeding device in which the feeding roller 6 is normally lifted up and away from the top surface of the paper P, and then lowered when feeding the paper.

C. Effects of the Invention According to the present invention, the above-mentioned problem of skewed paper feeding can be solved, and the intended purpose can be well achieved.

[Brief explanation of drawings]

The drawing shows the main part of one embodiment of the device of the present invention.
2 is a sectional view, FIG. 3 is a front view, and FIGS. 4 and 5 are front views when the paper size used is small. P is a loaded paper, 6 is a feeding roller, and Wl-Wl is a weight for adjusting pressure contact force.

Claims (1)

[Claims] (1) In a cut sheet feeding device that separates and feeds stacked cut sheets one by one by pressing the feeding roller against the upper surface of the cut sheets, the center of gravity of the feeding roller is set almost perpendicular to the sheet feeding direction. A cut sheet feeding device characterized in that it is equipped with a movable weight that shifts in a direction in which the cut sheet is fed.