JPH0356331A - Paper feeding device - Google Patents

Abstract

PURPOSE:To feed the lowermost one of stacked sheets alone by setting a front lip edge of an opening in a vacuum tank so that it aligns with the leading end face of a sheet set on the vacuum tank. CONSTITUTION:Upon paper feed, the leading end face of a sheet 12 aligns with a front lip edge of an opening 6 in a vacuum tank 6. As a result, the leading end of the sheet 12 sucked by the opening 6 is surely separated from other sheets 12 thereabove which are floated up by jetted air from a jet hole 11 in a blower tank 10, without being floating up by the jetted air. Accordingly, the lowermost one of the stacked sheets 12 alone can be fed.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a paper feeding device.

BACKGROUND OF THE INVENTION Conventionally, this type of paper feeding device has been used in copying machines, etc., and its usage will be briefly explained with reference to a copying machine shown in FIG. 3 in which the paper feeding device of the present invention is also used. .

Reference numeral 1 designates the main body of the copying apparatus, 2 a paper table consisting of a document table provided on the upper part, 3 an end plate, 4' a paper feeder, 12 a sheet of original, 16 a first turn path, 17 18 is a horizontal conveyance path, 18 is a second turn path, 19 is a conveyance belt, 20 is a platen glass, 21 is a first switching claw, 2
2 is a third turn path, 23 is a paper ejection path, 24 is a paper ejection roller, 25 is a paper ejection port, 26 is a reversal paper ejection port, 27 is a second switching pawl, 28 is a reversal paper ejection path, 29 indicates the sensor respectively.

The operation of the paper feeding device 4' in such a device will be explained with reference to FIG.

When the start key (not shown) of the copying machine 1 is pressed, the blower (not shown) rotates and blows the blowhole 1 of the blower tank 10.
Compressed air is ejected from the paper stack l2, causing the leading edge of the paper stack l2 to rise up. The lowest sheet of paper is attracted to the paper feed belt 7.

Then, the clutches (not shown) of the drive shafts 9 of the paper feed belts 1 to 7 are turned on, and the paper feed belt 7 is rotated counterclockwise to send the lowest sheet of paper attracted thereto to the first turn roller 16. . Sensor 2 installed immediately after this turn roller〕6
9 detects this paper, the intake of the vacuum tank 5' is stopped by the action of a valve (not shown) and the clutch is turned off, but the paper feed belt 7 is rotated by the paper being pulled out, and in this way Feeding of this paper is completed.

Problems to be Solved by the Invention However, in the conventional paper feeding device 4' as described above,
As is clear from FIG. 4, the tip edge of the opening 6' of the vacuum tank 5' is located on the vertical line Vertical line y ahead by distance *Q in direction
Located on '-y'. For this reason, it is difficult for suction force to act on the tip of the paper bundle 12, and especially in the case of curled paper, there is a strong tendency for the paper feed bells 1 and 7 to separate from each other. There was a problem in that it became difficult to fit between the lowest sheet of paper and the sheet above it, making it difficult to separate the two properly, resulting in double feeding.

Furthermore, since the intake holes 8 of the paper feed bells 1 to 7 do not always start feeding paper at the tip edge of the opening 6', the above-mentioned tendency becomes even more pronounced.

Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional paper feeding device, and to separate the lowest sheet of paper on the vacuum tank from its second layer using air blown from the blower tank. It is an object of the present invention to provide a paper feeding device that can reliably perform paper feeding and prevent the occurrence of quintuple feeding.

Means for Solving the Problems In order to achieve the above-mentioned objects, the present invention has the following features: 4. The tip edge of the opening of the vacuum tank is in a position where it coincides with the tip edge surface of the paper placed on the vacuum tank. It is something that

Further, in this invention, the width of the opening of the vacuum tank is made wider than the width of the paper feed belt.

Function: In the paper feeding device of the present invention as described above, when paper is fed, the leading end surface of the paper is in a position aligned with the leading edge of the opening of the vacuum tank, so that it is sucked by the opening and transferred to the blower tank. It will not float up even with the fumes from the top, and will be reliably separated from the second sheet of paper that floats up, allowing only the lowest sheet to be fed.

Furthermore, since the width of the opening is wider than the width of the paper feed belt, even if the intake hole to the paper feed bell 1 is not in the same position as the edge of the tip of the opening, the edge of the tip of the opening The suction prevents the bottom paper from lifting up.

Embodiment 1 The embodiment of the present invention shown in FIGS. 1 and 2 is different from the conventional example described above in the position XX of the edge 11 of the opening 6 of the vacuum tank 5 of the paper feeder 4; The position Y-Y of the leading end surface of the sheet east 12 placed thereon must be at the same position, and the width W of the opening 6 must be the same as that of the sheet feed bell 1.
It is larger than the width W of No. 7, and there is no other particular difference.

Such a paper feeder 4 feeds paper based on exactly the same principle as the conventional paper feeder 4'.

However, in this paper feeding device 4, since the leading edge of the opening 6 and the leading end surface of the paper bundle 12 are in the same position, the opening 6 formed by the vacuum tank 5 and the intake hole 8 of the paper feeding belt 7
Due to the suction action through the paper feeder belt 7, the leading edge of the lowest sheet of paper does not float up from the paper feed belt 7 even though it is caused by the fumes from the blowhole 11 of the proar tank 10. Separation from paper is ensured, and only this paper is fed without double feeding.

Furthermore, since the width of the opening 6 is wider than that of the paper feed bells 1 and 7, there is no possibility that the intake hole 8 of the paper feed bells 1 and 7 may be located behind the tip edge of the opening 6. However, the openings on both sides of the paper feed belt 7 in the opening 6 prevent the lowest paper from floating up.

Effects of the Invention This invention is as described above, and since the leading end edge of the opening of the vacuum tank is in a position that coincides with the leading edge surface of the paper, even if the blower is emitted from the blower tank during paper feeding operation, it will be avoided. The lower paper does not lift up and is reliably separated from the paper above it that floats up, so that only the lowest paper is fed and there is no double feeding, and the width of the opening is Since it is wider than the width of the paper belt, it has the effect of precisely preventing the lowest paper from lifting up, regardless of the position of the intake hole of the paper feed belt.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG.
This figure is a schematic explanatory diagram of a part of a copying machine equipped with a conventional paper feeding device, and FIG. 4 is a diagram similar to FIG. 2 regarding the conventional paper feeding device. 2... Paper table 4... Paper feed device 5... Vacuum pump 6... Opening 7... Paper feed bell 1...
8... Intake hole 10... Proar tank 11... Fumarole 12.
...Paper 8

Claims (1)

[Claims] 1. A paper table, a vacuum tank provided in front of the paper table and having an opening on the top surface, and a plurality of vacuum tanks that are wound around the vacuum tank and moved over the opening. In a paper feeding device that has a paper feeding belt having an intake hole of A paper feeding device characterized by being located at a position that coincides with the leading end surface of a sheet of paper placed thereon. 2. The paper feeding device according to claim 1, wherein the width of the opening of the vacuum tank is wider than the width of the paper feeding belt.