JP2539662B2 - Sheet feeding device - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a sheet feeding device that feeds a laminated sheet such as a prepaid card, a flexible printed circuit board, a film, or a green sheet one by one.

[Prior art]

Conventionally, as a method of sending out the laminated sheets one by one by blowing out air, for example, Japanese Patent Publication No. 396310
As shown in No. 6, the air is ejected from the air ejection port provided on the flat plate toward the top of the stacked sheets, and the top sheet is levitated by the Bernoulli chuck that causes decompression according to Bernoulli's theorem. Is a device which is brought into contact with the peripheral surface of a roller provided below the ejection port and is fed out by the rotation of the roller. Alternatively, Japanese Utility Model Sho 49-139781 and Japanese Utility Model Sho 61-197037
As shown in No. 3, a belt is arranged below the suction port of a suction device that sucks air to suck the sheet, and the sheet is sent out by bringing the sheet into contact with the lower surface of the belt.

[Problems to be Solved by the Invention]

Due to the progress of electronics related technology in recent years, one thin sheet, one soft sheet or one brittle sheet is laminated one by one on an inspection machine, press machine, printing machine, etc. without adhering or deforming scratches or dirt. The process of sending them out one by one has become necessary. For example, it is a prepaid card, a flexible printed circuit board, a ceramic green sheet, and the like, and these sheets have a problem that scratches, stains, and deformations lead to defective products. As a part of the conventional technology, as described above,
In the −6310 publication, a sheet is levitated by a Bernoulli chuck that ejects air toward the sheet from an air ejection port provided on a flat plate to generate a negative pressure, and the levitated sheet is brought into contact with the peripheral surface of the roller. The sheet is sent out by the rotation of the roller, but in this case, the contact area between the sheet and the roller is small, and excessive force is applied to the sheet at that portion, which may deform or damage the sheet. Further, when the sheet comes off from the lower portion of the suction tool, the sheet is inclined and it becomes impossible to feed it horizontally. Moreover, since the contact area between the sheet and the roller is small, the sheet could not be sent out in a predetermined direction without the guide plate. Further, in the Bernoulli chuck, since the diameter of the air ejection port cannot be increased, the change in the flow rate ejected from the air ejection port due to the displacement in the direction perpendicular to the surface of the held sheet is small, so that the holding force for the sheet is reduced. Especially, since the holding and restoring force is small, the holding stability is poor, and there is a drawback that the sheet is dropped due to a small vibration or a deviation of the sheet. Further, in the above-mentioned Japanese Utility Model Publication No. 49-139781, a suction port of a contact-type suction device that sucks air by sucking air is provided in a space between parallel belts at a height higher than the lower running line of the belt. , The sheet is sent by contacting the belt, but this one uses a suction type suction tool, so the center part of the sheet tends to warp, contacting the suction tool, causing scratches, Sometimes it becomes impossible to send out. If the sheet is relatively flexible like the prepaid card, the central portion is likely to be warped. For this reason, it is important to keep the balance between the suction force for holding and the amount of warping, and in general, it is necessary to reduce the belt interval, and in addition, in order to hold the suction device, each suction tool is placed in a narrow gap between the belts. It was not economical because the number of belts and the number of suction tools increased, and it was difficult to adjust the air suction amount. Incidentally, the above-mentioned No. Sho 61-197037 is a system in which an air suction port is provided on the upper surface of a belt with holes, and a sheet is sucked and sent in contact with the lower surface of the belt. The wear was severe, the amount of dust was large, the environment was bad, and the belt had to be changed frequently, which was not economical.

[Means for Solving the Problems]

In order to solve the above problems, the present invention is a sheet feeding device that sequentially feeds stacked sheets from the uppermost sheet, and is a pair of belts that have an upper traveling portion and a lower traveling portion and that circulate. Are formed in parallel with each other across the space and at the same height in the space of the conveying tool provided with an air inlet into which high-pressure air flows, and downward from the periphery of the space. A non-contact type sheet suction tool in which a bowl-shaped base portion forming a downward-opening cushion chamber is formed inside by the formed peripheral wall portion and the suction surface on the lower surface of the base portion does not contact the sheet is the transport tool. Are arranged with a horizontal gap between them, and the suction surface is directed downward at a height higher than the lower surface of the lower traveling portion, and the sheet is movable up and down in a stationary frame and is fed out of the sheet. Placed on a lifting platform that rises according to Can be solved by providing a sheet feeding apparatus, characterized in that the.

[Action]

A pair of revolving belts having an upper traveling portion and a lower traveling portion are provided parallel to each other across a space and at the same height, and provided in the space of the transportation tool. When air is ejected from the non-contact type sheet suction tool to the uppermost sheet of the stacked sheets, the average pressure between the suction surface and the space between the sheets falls below atmospheric pressure, and the sheet floats in the air, and the suction surface Is contacted with the lower surface of the lower traveling portion of the belt, which is provided at a uniform height below, i.e., horizontally, and is sent out as the belt moves. Therefore, since the seat that floats in the air contacts the lower running portion of the belt over the entire length, the contact area between the seat and the belt is large, and no local force is applied to the seat.
The sheet is not bent, distorted, or damaged, and is always held horizontally even if it is disengaged from the lower surface of the sheet suction tool, and it is possible to accurately feed the sheets horizontally without tilting. . Further, since the sheet suction device is a non-contact type and a small gap is formed between the sheet suction device and the sheet, even if the air supply amount is excessive, the sheet is not bent more than a certain amount, and the distance between the belts is increased. Since it can be widely adopted, the number of belts can be reduced, and along with this, the number of sheet suction tools themselves can be reduced, and the apparatus can be simplified and the cost can be reduced. Further, even if the air supply amount is excessively large, the sheet does not come into contact with the sheet suction tool, so that the operation of the apparatus is easy. Further, since the seat is in the stationary frame, it can be sent out to a predetermined position without being displaced during the ascent / descent. Further, the non-contact type sheet suction tool used in the present invention has the lower open cushion chamber, so that it has an ejector effect and a Bernoulli effect as a negative pressure generating mechanism that becomes a suction force, and a positive pressure generation that becomes a repulsive force. As a mechanism, it has a fixed pressure air cushion effect and an air flow cushion effect, and is 1.4 times more attractive and 1.3 times more repulsive than conventional so-called Bernoulli chucks that have air outlets on a flat plate. Therefore, efficient operation is possible. Further, since the non-contact type sheet suction device has the lower opening cushion chamber, the diameter of the air ejection port is larger than that of the conventional Bernoulli chuck, so that the held seat is prevented from being displaced in the vertical direction. Since the change in the amount of air blown out is large and the holding force on the sheet, especially the holding restoring force, is great, the holding stability is excellent, and the sheet is not dropped due to vibration or sheet misalignment, so the sheet is delivered reliably. improves.

【Example】

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the apparatus of the present invention is one in which a sheet suction tool A is arranged on a conveyor tool B using a belt, and the sheet suction tool A as shown in FIG. A device similar to the patent No. 1563948 invented by K.K. The sheet suction tool A is an air inlet 1 into which high-pressure air C flows.
The upper portion 2 provided with the above and the peripheral wall portion 3 extending downward from the periphery of the upper portion 2 are provided with a bowl-shaped base portion D having a space for forming a downwardly opened cushion chamber 5 therein, while The base portion D has a flat and wide suction surface 4 formed at the lower end of the peripheral wall portion 3 at the same height over the entire circumference. This sheet suction tool A supplies air from the air inlet 1 when the suction surface 4 is arranged above the seat 6 at a large distance h, and when the air is jetted toward the seat 6, the cushion chamber 5 and the suction chamber are sucked. The space between the surface 4 and the seat 6 is decompressed by the ejector effect and the Bernoulli effect, and the seat 6
Pull up. When the seat 6 is pulled up and the distance h becomes small, the pressure in the space formed by the cushion chamber 5 and the suction surface 4 and the seat 6 rises due to the pressure chamber type air cushion effect and the cushion effect of the air flow, and the seat 6 Push down. According to the above principle, the sheet 6 is the sheet suction tool A.
It is kept in the air without touching. Thus, the sheet suction tool A is formed as a non-contact type that does not contact the sheet 6. FIG. 4 shows the relationship between the distance h and the force F acting on the sheet 6 (the positive sign indicates the force to push down the sheet 6). W indicates the weight of the sheet 6. The distance between the sheet suction tool A and the sheet 6 becomes small and h <c
Then, F <−W, and the sheet 6 floats up. At h = b, the suction force becomes maximum, and when h <a, the force of pushing down the sheet 6 works. The sheet suction tool A used in the present invention as described above has an ejector effect and a Bernoulli effect as a negative pressure generating mechanism serving as a suction force, and a pressure chamber type air cushion effect and an air flow effect as a positive pressure generating mechanism serving as a repulsive force. It has a cushioning effect, the suction force is 1.4 times, and the repulsion force is 1.4 times greater than that of a so-called Bernoulli chuck in which a conventional flat plate is provided with an air outlet.
1.3 times better. Further, since the sheet suction tool A has the cushion chamber, the diameter of the air ejection port is larger than that of the conventional Bernoulli chuck, so that the change in the air ejection amount with respect to the displacement of the held sheet 6 in the perpendicular direction is large, Since the holding force for the sheet 6, particularly the holding restoring force is large, the holding stability is excellent, and the sheet is not dropped due to vibration or deviation of the sheet. The carrier B is provided above the frame 7, and the frame 7 is surrounded by a front wall 11 on the side where the sheet 6 is taken out, a pair of side walls 12 and 12, and a rear wall 20, and a large number of layers are stacked. A rectangular tube wall that guides the seat 6 is formed. Further, an elevating table 13 for elevating and lowering the laminated sheets 6 is provided in the frame 7, and horizontal shafts 10 and 18 on both sides of the horizontal shafts 10 and 18 which are bridged over the columns 21 and 22 are provided in front of and behind the upper portions of the side walls 12 and 12. Two belts B1 and B1 are stretched around pulleys 16, 16 and 17, 17 having a diameter. As a result, the belts B1 and B1 form the conveying tool B which is parallel to the upper portion of the frame 7 and has a space. The shaft 10 is connected to a motor 9 and is driven so that the lower traveling portion 8 is on the delivery side of the sheet 6. The lower surfaces of the two belts B1 and B1 are arranged parallel to each other at the same height. The sheet suction tool A is attached to the upper part of the support column 21 by the bracket 14, and the base portion D of the sheet suction tool A is the above-mentioned 2
The belts B1 and B1 are arranged in a space between the belts B1 and B1 with a gap G in the horizontal direction. Further, the sheet suction tool A is provided with the suction surface 4 facing downward and at a height higher than the lower surface of the lower traveling portion 8 of the belts B1 and B1. The air inlet 1 is connected to a high pressure air source via a pipe and a valve (not shown). The lifting table 13 has a distance that allows the uppermost sheet 6 stacked on the upper surface thereof to be sucked (see FIG.
= Near b), the lift bar 15 is sequentially raised while being detected by the position sensor. Next, the operation of the sheet feeding device of the present invention will be described. When the sheet 6 stacked on the elevator 13 rises and the uppermost sheet 6 reaches a predetermined position, high-pressure air is supplied to the air inlet 1 of the sheet adsorbing tool A toward the uppermost sheet 6. Erupted. Based on the above-mentioned principle, only one sheet 6 at the uppermost position immediately floats up to the suction surface 4 based on the above-mentioned principle, and the lower surface of the lower traveling portion 8 of the belts B1 and B1 provided below the suction surface 4 is Contact. Since the belts B1 and B1 are moving in the sheet feeding direction, the sheet 6 that is in contact with the lower traveling portion 8 of the belts B1 and B1 is horizontally fed together with the movement of the lower traveling portions 8 of the belts B1 and B1. When the sheet is sent out, the lift bar 15 raises the next uppermost sheet 6 stacked on the elevating table 13 to a predetermined position, sucks and floats by the sheet suction tool A, and sequentially sends out. The sheets 6 stacked in this way are sent out one after another, and when the operation of the last one is completed, this is automatically detected, and when the ejection of air is stopped, the rotation of the simultaneous belts B1, B1 is stopped. As the sheet suction tool A of this example, the same one as the patent No. 1563948 relating to the inventor of the present invention is used as described above,
The suction force, repulsion force and holding stability are far superior to those of the prior art.

【The invention's effect】

As described above, the device of the present invention can accurately convey even a flexible sheet such as a prepaid card without damaging it, and the simplification of the device improves economy and maintainability. Further, since the sheet suction device is a non-contact type, even if the amount of supplied air becomes excessive, the sheet does not come into contact with the sheet suction device to be sucked, so that the operation is easy. Compared to other Bernoulli chucks, the holding force for the sheet, especially the holding and restoring force is large, so it is excellent in holding stability.Because the sheet does not drop due to vibration or deviation of the sheet, the reliability of feeding the seam is improved. did.

[Brief description of drawings]

FIG. 1 shows an external view of an embodiment of the present invention. FIG. 2 shows a side sectional view of an embodiment of the present invention. FIG. 3 shows a side sectional view of the sheet suction tool A. FIG. 4 is a diagram showing the relationship between the suction distance of the sheet suction tool A and the suction force. In the figure: 1: Air inlet 4: Suction surface 5: Cushion chamber 6: Seat 8: Lower running part of belt B1 9: Motor 13: Lifting table A: Sheet suction tool B1: Belt B: Conveyor tool G: Gap C: High Pressure Air D: Base

Claims (1)

(57) [Claims] 1. A sheet feeding device for sequentially feeding stacked sheets from the uppermost sheet, wherein a pair of belts having an upper traveling portion and a lower traveling portion are arranged in parallel with each other with a space therebetween. In addition, inside the empty space of the conveyors arranged at the same height, an upper portion provided with an air inlet for high-pressure air and a peripheral wall portion formed downward from the periphery of the upper portion are provided inside. A non-contact type sheet suction tool that forms a bowl-shaped base that forms an open-bottomed cushion chamber, and the suction surface of the lower surface of the base does not contact the sheet, forms a horizontal gap between the conveyance tool and the conveyance tool. Separately and with the suction surface facing downward at a height higher than the lower traveling portion lower surface, the seat is movable up and down in a stationary frame, and rises according to the delivery of the seat. It is characterized by being stacked and placed on Door delivery device.