JPS613161A - Paper feed device - Google Patents

Abstract

PURPOSE:To make the titled device light in weight and compact, to reduce its cost, to curtail its man-hour, and to obtain its high reliability, by providing a point of application of a wire in the vicinity of the center of gravity of a paper feed base, and also providing a lifting rail and a lifting roller between the center of gravity of the paper feed base and the point of application of the wire. CONSTITUTION:One sheet of the upper most position of a form 12 contained in a laminated state on a feed paper base 11 by a form supply means 18 passes through between a lower guide plate 19a and an upper guide plate 19b of a guide means 19 and it is fed to under a paper feed roller 22 of the body. The paper feed roller 22 is rotated by a copying operation of a copying machine, and the form is fed into the inside of the copying machine. When said operation is repeated and the form on the paper feed base 11 decreases, a descent of a position of the uppermost position of the form 12 is detected by a sensor 23, and by driving a driving means 17, a drum 16 is rotated, a wire 15 is wound up and the paper feed base 11 is made to ascend, and when it ascends to a prescribed position, it is detected by the sensor 23 and the driving means 17 is stopped. By repeating such an operation, the paper feed base 11 continues to ascend by holding a position of the form of the uppermost position on the paper feed base 11 at an exact height.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a paper feeding device that can be attached to a copying machine or the like to feed a large amount of paper.

Conventional configurations and their problems In recent years, as copiers have become faster and more voluminous copies have become available, there has been a growing demand for larger capacity paper feed cassettes in the market. is proposed.

Hereinafter, a conventional large-capacity paper feeder will be described with reference to the drawings. Figure 1 is a cross-sectional view of a conventional large-capacity paper feeder.
FIG. 2 is a plan view of the same. In FIGS. 1 and 2, 1 is a paper feed table, 2 is a lifting rail, 3 is a lift roller, 4 is a chain that drives the paper feed table 1, 6 is a sprocket that drives the chain 4, and 6 is a sprocket 6. 7 is a guide member for regulating the position of the paper feed tray 1 in the Y direction; 8 is a rail on which the guide member 7 slides; 9 is the center of gravity position when paper is stored; It is a one-way clutch.

In the large-capacity paper feeder configured as described above, the drive device 6
By rotating the splot 5 and moving the chain 4 in the vertical direction, the paper feed table 1 is raised and lowered in the vertical direction. However, in such a drive using a chain, the minimum diameter of the sprocket 5 is limited and a plurality of sprockets 6 must be used, resulting in large space limitations. Therefore, it becomes difficult to arrange the chain's action point near the center of gravity of the paper feed table 10, and it has to be placed at the tip of the paper feed table 1 away from the center of gravity. As a result, a large moment is applied to the paper feed tray 1, the lifting roller 3, the lowering rail 2, etc. during lifting and lowering, so these members are limited in terms of strength.1. The plate thickness must be increased or the shape must be increased, making it extremely difficult to create a lightweight and compact design.

In addition, since the paper feed table 1 is likely to become distorted when raised and lowered, the lifting rollers 3, the lifting rails 2, etc. must also be installed near the chain 4, which makes it difficult to arrange other paper feeding means. Not affected. Furthermore, since the shapes of the lifting rollers and the lifting rails are flat, it is difficult to regulate their positions in the Y direction, and guide members 7 and rails 8 are required. Furthermore, a one-way clutch 10 is interposed between the drive device 6 and the sprocket 6 so that force is not forcibly applied by the drive device 6 even if the safety 1r's arms and hands are jammed.

Therefore, the above configuration has the disadvantage of being structurally complex and expensive. Furthermore, in order to accommodate these complex mechanisms, the depth and height of the large-capacity paper feeder increases, resulting in an unnecessarily large installation space.
It had the disadvantage that it was difficult for women to handle because it was heavy.

OBJECTS OF THE INVENTION An object of the present invention is to eliminate the above-mentioned conventional drawbacks, and to provide a large-capacity paper feeding device that is simple in structure, lightweight, compact, inexpensive, and highly reliable.

5. Structure of the Invention A paper feeding device of the present invention comprises: a paper feeding tray for storing sheets in a stacked state; a paper feeding means for contacting and feeding out the uppermost sheet on the paper feeding tray; and this paper feeding means. a lifting rail that maintains the orientation of the paper feed table; and a lifting roller that cooperates with the lifting rail.

The paper feed tray is suspended vertically by a suspension device that suspends the paper feed platform and a drive unit that drives the suspension device up and down, and the point of action of the suspension device is provided near the center of gravity of the paper feed platform, and
Said lifting rail and said! 1. The present invention is characterized in that a lowering roller is provided between the center of gravity of the paper feed tray and the point of action of the suspension.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Fig. 3 is a cross-sectional view of a large-capacity paper feeder according to the present invention, Fig. 4 is an explanatory view of the elevating operation of the paper feed tray, and Figs. 5 and 6 are explanatory views of the elevating rail and elevating roller. be.

In FIGS. 3 to 6, 11 is a paper feed tray, and 12 is paper stored in a stacked state. The paper feed tray 11 is inclined in the direction in which the paper travels so that the front end is lower than the rear end, so that when placing paper on the paper feed tray 11, it is easy to align the leading edge of the paper. It has become. Reference numeral 13 denotes a lift rail, and 14 denotes a lift roller fixed to the paper feed table 11. The lifting roller 14 moves while rolling on the inner surface of the lifting rail 13. 15 is a wire that supports the paper feed table.

16 is a drum for winding the wire 16; 17 is a drum 16;
18 is a paper supply means such as a friction roller, 19 is a guide means, 20 is a frame, 21 is a cover, 22 is a paper feed roller of the main body of the copying machine, and 23 is an upper limit sensor.

In FIG. 4, the load W of the sheets 12 stacked on the sheet feed tray 11? The tension applied to the wire 15 is balanced. On the other hand, the moment acting on the paper feed tray 11 is determined by the product of the load W and the distance from the center of gravity to the point of action of the wire, and this moment acts as a force F1 that causes the elevating roller 14 to act on the elevating rail in the vertical direction. do. Therefore, Wx
The relationship L,=F,xL2 holds true. In this embodiment, by moving the point of action of the wire 16 as close to the center of gravity as possible, the value of Ll is reduced, the moment acting on the paper feed tray 11 is reduced, and the force applied to the lifting rail 13 is reduced.
．． By reducing the size, the paper feed tray 11 and the elevating rail 13 are made smaller and lighter. Further, by arranging the elevating rail 13 and the elevating roller 14 between the center of gravity of the paper feed tray 11 and the point of action of the wire 16, twisting during elevating and lowering operations is prevented and reliable elevating and lowering operations are realized.

The sixth factor is a plan view of the relationship between the elevating rail 13 and the elevating roller 14, and the elevating rail 13 only supports the moment of the paper feed table 11 and has the effect of regulating the position in the IY direction. It has an inner surface with a radius of curvature R2 that is approximately the same as the radius of curvature R5 of the lowering roller 14.

Furthermore, the minimum dimension of the open portion in the Y direction is made smaller than the maximum outer diameter dimension B of the metal roller 14 to prevent displacement in the Y direction. This allows the position of the paper feed table 11 to be adjusted without a separate guide or rail.

Note that the shapes of the lifting rail 13 and the lifting roller 14 are as follows:
It may also have a concave shape as shown in FIG.

In this case as well, the relationship R4 in R8, C<D may be established.

The operation of the paper feeding device in the large-capacity paper feeding machine of this embodiment configured as described above will be described below. First, the topmost sheet of the sheets 12 stored in a stacked state on the sheet feed tray 11 from the sheet supply means 181C passes between the lower guide plate 191LJ and the lower guide plate 19b of the guide means 19, and passes through the sheet feed roller 22 of the main body. It is sent to the bottom. The paper feed roller 22 rotates due to the copying operation of the copying machine, and feeds paper into the interior of the copying machine.

When the number of sheets on the paper feed tray 11 decreases by repeating the above operations, the sensor 23 detects the lowering of the uppermost position of the sheet 12, and the driving means 17 is driven to move the drum 1.
6 is rotated to wind up the wire 16 and raise the paper feed table 11. When it rises to a predetermined position, it is detected by the sensor 23 and the driving means 17 is stopped. By repeating such operations, the paper feed tray 11 continues to rise while maintaining the position of the uppermost sheet on the paper feed tray 11 at an accurate height.

As described above, according to this embodiment, a large-capacity sheet feeding device that performs reliable lifting and lowering operations with an extremely simple structure is realized.

Effects of the Invention As is clear from the above description, the present invention comprises a paper feed tray for storing sheets in a stacked state, a lift rail for maintaining the posture of the paper feed tray, and a lift roller that cooperates with the lift rail. , a wire that suspends the paper feed tray, and a drum that drives the wire.

and a driving means for driving the drum, and as a result, an extremely simple structure can be achieved without a complicated and expensive mechanism. Further, by providing the point of action of the wire near the center of gravity of the paper feed table, and providing the lifting rail and the lifting roller between the center of gravity of the paper feed table and the point of action of the wire, the paper feed table and Since the moment acting on the elevating rail can be reduced, the paper feed table and the elevating rail can be made smaller and lighter. Also,
! Since the frictional resistance of the I-lowering roller can also be reduced, the drive device can be made smaller and more energy efficient. Furthermore, since the position in the Y direction can be regulated using only the 'fl lowering roller and the lifting rail, no sliding parts for regulating the position in the Y direction are required, and the number of parts can be reduced and the load caused by rolling friction can also be significantly reduced. Furthermore, by suspending the paper feed tray with wires, even if you accidentally jam your arm or hand under the paper feed tray while it is lowering, no force will be applied to the drive unit. This eliminates the need for a special one-way clutch for safety reasons. Furthermore, there is no need for any pulleys for wire routing, making it possible to significantly reduce the number of parts and assembly man-hours.

In this way, the present invention has an extremely simple structure and mechanism, so there is no need to increase the depth or height of the large-capacity paper feeder to accommodate these mechanisms, and the installation space can also be reduced. .

Furthermore, the weight can be significantly reduced, making it lightweight and compact, making it easy for even women to handle, and the significant simplification of the structure has the advantage of being lightweight and compact, reducing costs, reducing man-hours, and achieving high reliability. is obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional large-capacity paper feeder. FIG. 2 is a plan view of the same, FIG. 3 is a sectional view showing an embodiment of a large-capacity paper feeder according to the present invention, and FIG. 4 is a sectional view of a conventional large-capacity paper feeder. FIG. 6 is an enlarged view of the raising and lowering operation of the paper feed table in the same apparatus, and FIG. 11... Paper feed table, 12... Paper stored in a stacked state, 13... Elevating rail, 14...
...°・v1 descending roller, 15...Wire, 1
6...Drum, 17...Driving means, 18...
... Paper supply means, 19 ... Guide means. Figure 1 Figure 3 Figure 4 Figure 5 Figure 6

Claims (3)

[Claims] (1) A paper feed tray that stores sheets in a stacked state, a paper supply means for contacting and feeding out the uppermost sheet on the paper feed tray, and copying of the paper fed out by the paper feed means. a lifting rail for maintaining the posture of the sheet feeding tray; a lifting roller that cooperates with the lifting rail; and a suspension device for suspending the sheet feeding tray; and a driving means for driving the suspension device up and down, the suspension device is suspended so as to be able to rise and fall freely, and the point of action of the suspension device is provided near the center of gravity of the paper feed table, and the lifting rail and the lifting roller are connected to the center of gravity of the paper feed table. and a point of action of the suspension device. (2) A patent characterized in that the shape of the elevating rail has a radius of curvature that is approximately the same as the outer peripheral shape of the elevating roller, and the minimum dimension of the open part of the elevating rail is smaller than the maximum outer diameter dimension of the elevating roller. A paper feeding device according to claim 1. (3) The suspension device is a wire, the upper end of the wire is fixed to a wire drum, the other end is fixed to a paper feed tray, and the paper feed tray is raised and lowered by rotationally driving the wire drum. A paper feeding device according to claim 1, characterized in that: