Vacuum pad

Abstract

To provide a vacuum pad capable of sucking and moving pieces of sheet-like and film-like work, one by one.SOLUTION: A vacuum pad 1 comprises a main body 2 which has a space part 2a formed communicating with an external vacuum source 6 and a pair of a first arm 3 and a second arm 4 in a hollow shape which extend from the main body 2 while communicating with the space part 2a, and the main body 2 has a fitting part 2b fitted with an external holder 9 and an expansion part 5 contracting when the space part 2a is decompressed and expanding when the space part 2a is released from being decompressed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vacuum pad used in a work transfer device that transfers works one by one.

Background Art

[0002] In various manufacturing facilities such as packaging facilities, printing facilities, and bookbinding facilities, there is known a work transfer device that has a vacuum pad for adsorbing a work by a vacuum pressure and transfers the works one by one.

[0003] When adsorbing and transferring sheet-like or film-like works including paper and synthetic paper one by one, the works may be adsorbed in a state where a plurality of works are stuck together by Coulomb force. In addition, the suction force of the vacuum pad may reach below the work, and the works may be adsorbed in a state where a plurality of works are stuck together. As a countermeasure against the adsorption of the works to each other, attempts have been made to separate the works from other works attached to the lower surface of the work by blowing air from the outside while the vacuum pad is adsorbed to the upper surface of the work, and attempts have been made to separate the work from other works attached to the lower surface of the work by bending the work while the vacuum pad is adsorbed to the upper surface of the work (Patent Document 1: Japanese Patent Laid-Open No. 8-337328, Patent Document 2: Japanese Patent Laid-Open No. 2010-064814, Patent Document 3: Japanese Patent Laid-Open No. 2012-086950, Patent Document 4: Japanese Patent Laid-Open No. 2017-218260).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] Among the prior arts, a configuration in which a plurality of vacuum pads perform different operations to carry out adsorption operations and separation operations requires a large number of components and a complex control mechanism. On the other hand, a configuration using a vacuum pad with a simple structure requires an additional separation device that blows air from the outside.

[0006] In recent years, with the efforts to reduce microplastic waste, there has been a trend to replace plastic films with synthetic papers containing paper fibers, and there is a market demand for a highly versatile vacuum pad that can accommodate changes in work materials. In addition, there is a market demand for a vacuum pad that can control desired operations with a simple control mechanism without additional capital investment in complex control mechanisms, separation devices, and other equipment.

Means for Solving the Problems

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a vacuum pad that operates with a simple control mechanism and can adsorb and move sheet-like or film-like workpieces one by one.

[0008] As one embodiment, the above problems are solved by the solutions disclosed below.

[0009] The vacuum pad according to the present invention is used in a work moving device that moves a sheet-like or film-like work, and includes a main body in which a space portion communicating with an external vacuum source is formed, and a pair of hollow-shaped first arms and second arms extending from the main body while communicating with the space portion. The main body is characterized by having a mounting portion to which an external holder communicating with the external vacuum source is attached, and an expansion and contraction portion that contracts by depressurization of the space portion and expands by release of the depressurization of the space portion.

[0010] According to this configuration, as the expansion and contraction part contracts due to the decompression of the space part, the first arm and the second arm approach each other while adsorbing and bending the workpiece, so that the adsorbed workpiece can be separated from other workpieces. Then, the workpiece is moved to a desired movement location by the workpiece transfer device, and as the expansion and contraction part expands due to the release of the decompression of the space part, the first arm and the second arm move away from each other to release the workpiece, so that the workpiece can be placed at the desired movement location. Therefore, it operates with a simple control mechanism and can adsorb and move workpieces one by one.

[0011] As an example, for the workpiece at the uppermost position in a workpiece aggregate where a plurality of workpieces are stacked, it is configured to adsorb the workpiece and bend the workpiece with the decompression and release the workpiece with the release of the decompression. According to this configuration, even for a workpiece aggregate where a plurality of workpieces are stacked, it is easy to adsorb and move workpieces one by one.

[0012] As an example, suction cups are respectively arranged at the tips of the first arm and the second arm. According to this configuration, it is easy to adsorb the workpiece with the decompression. As an example, joints are respectively arranged in the middle of the first arm and the middle of the second arm, and the first arm and the second arm are bent by the joints in the direction in which the suction cups approach each other. According to this configuration, it is easy to make the suction surfaces of the pair of suction cups flush in the initial state, so it is easy to simultaneously adsorb the pair of suction cups to the workpiece when adsorbing the workpiece. Moreover, it is easy to adsorb the workpiece with the decompression and bend the workpiece. And when releasing the workpiece with the release of the decompression, it is easy to return the workpiece to a flat state. Moreover, when continuously adsorbing the workpiece in the state of the release of the decompression, it is easy to simultaneously adsorb the pair of suction cups to the workpiece.

[0013] As an example, it is a vacuum pad of an integral structure made of an elastomer, elastic rubber, or a composite material thereof. With this configuration, while minimizing the number of parts to facilitate manufacturing, it can also be configured to be easily separated and recycled after consumption. As an example, it is a vacuum pad having a rotationally symmetric shape of 180° around the axis. With this configuration, it can be configured to be easily attached to an external holder, and when specialized for adsorbing and moving workpieces one by one, it can be formed into the most reasonable shape.

[0014] As an example, the telescopic part has a partition part arranged on the axis to partition the space part. As an example, the telescopic part has a bellows part arranged on the axis and contracting and expanding in a direction symmetric with respect to the axis. According to this configuration, it is easy to uniformly reduce the fluid pressure in the first arm and the second arm and uniformly release the pressure reduction. Moreover, it is easy to uniformly contract and uniformly expand the side of the main body where the first arm is connected and the side of the main body where the second arm is connected.

Advantages of the Invention

[0015] According to the present invention, a vacuum pad that operates with a simple control mechanism and can adsorb and move sheet-like or film-like workpieces one by one can be realized.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

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Figure 11

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The vacuum pad 1 of the present embodiment is used in a workpiece transfer device 14 that transfers a sheet-like or film-like workpiece W1, and is adsorbed to the workpiece W1 at the uppermost position in a workpiece aggregate W in which a plurality of workpieces are stacked, causing the workpiece W1 to bend as the pressure is reduced, moving the workpiece W1 to a desired transfer location while maintaining the reduced pressure, and releasing the workpiece W1 as the pressure is released to place the workpiece W1 at the desired transfer location. This embodiment is applicable to all general sheet-like or film-like workpieces W1 such as paper, synthetic paper, resin sheets, resin films, or composites of paper and resin, or paper or synthetic paper with metal vapor deposition. In all the drawings for explaining the embodiment, members having the same function are denoted by the same reference numerals, and repeated explanations may be omitted.

[0018] As shown in FIG. 11, an external holder 9 is provided at the tip of a work transfer device 14 constituted by a robot arm or the like, and a vacuum pad 1 is attached to the external holder 9. Examples of the work transfer device 14 include an assembly / conveyance robot and a take-out machine exemplified by a scalar robot or the like. As an example, the work transfer device 14 is applied to various manufacturing facilities such as packaging facilities, printing facilities, and bookbinding facilities.

[0019] The external holder 9 is connected to an external vacuum source 11 via a flow path 12 made of a tubular body such as a tube, and a flow path switching valve 13 is provided in the middle of the flow path 12. The main body 2 of the vacuum pad 1 has a space portion 2a communicating with the external vacuum source 11. The flow path switching valve 13 is configured to switch between a position where the space portion 2a in the vacuum pad 1 is depressurized and a position where the pressure reduction of the space portion 2a is released and the atmosphere is opened. For example, by switching the flow path switching valve 13 to a negative position to depressurize the space portion 2a in the vacuum pad 1, the work W1 can be adsorbed. For example, by switching the flow path switching valve 13 to a positive position to release the pressure reduction of the space portion 2a in the vacuum pad 1, the work W1 can be released. Details of the usage mode of the vacuum pad 1 will be described later.

[0020] As an example, the vacuum pad 1 is an integral structure made of an elastomer, elastic rubber, or a composite material thereof. Examples of the elastomer or elastic rubber include nitrile rubber, silicone rubber, urethane rubber, fluororubber, butadiene rubber, NBR, HNBR, EPDM, and other known elastic resin materials.

[0021] First, the configuration of the vacuum pad 1A in the first example will be described below.

[0022] (First Example) FIG. 1 is a schematic perspective view showing a vacuum pad 1A according to the present embodiment. FIGS. 2 to 4 are views showing the usage mode of the vacuum pad 1A. FIG. 5 is a longitudinal sectional view of the vacuum pad 1A. Here, in order to easily explain the positional relationship of each part of the vacuum pad 1A, the directions are indicated by arrows X, Y, and Z in the figure. The Z-direction arrow in the figure is upward, and the reverse direction of the Z-direction arrow in the figure is downward.

[0023] As shown in FIG. 1, the vacuum pad 1A has a shape that is rotationally symmetric by 180° around the axis P1. As shown in FIGS. 1 to 5, the vacuum pad 1A includes a main body 2 having a space portion 2a communicating with an external vacuum source 11, and a pair of hollow-shaped first arms 3 and second arms 4 extending from the main body 2 while communicating with the space portion 2a. The main body 2 has a mounting portion 2b to which an external holder 9 communicating with the external vacuum source 11 is attached, and an expansion and contraction portion 5 that contracts by the decompression of the space portion 2a and expands by the release of the decompression of the space portion 2a.

[0024] As shown in FIGS. 1 to 5, the main body 2 has a substantially cylindrical mounting portion 2b to which an external holder 9 communicating with the external vacuum source 11 is attached. The mounting portion 2b has a mounting hole 2c formed in accordance with the outer diameter of the external holder 9. With this configuration, the vacuum pad 1A can be easily attached to the external holder 9.

[0025] As shown in FIG. 5, the expansion and contraction portion 5 has a partition portion 5a disposed on the axis P1 and partitioning the space portion 2a. In the upper part of the main body 2, a first arm 3 having a hollow portion 3a communicating with the space portion 2a and a second arm 4 having a hollow portion 4a communicating with the space portion 2a are disposed.

[0026] As shown in FIGS. 1 to 5, a thin portion 3c with a recessed upper side is formed at the base of the first arm 3, and a thin portion 4c with a recessed upper side is formed at the base of the second arm 4. With this configuration, the first arm 3 and the second arm 4 can easily move closer to each other and move away from each other.

[0027] At the tip of the first arm 3, a suction cup 3d with a suction surface 3e facing downward is arranged, and at the tip of the second arm 4, a suction cup 4d with a suction surface 4e facing downward is arranged. In the middle of the first arm 3, a joint portion 3b is arranged, and in the middle of the second arm 4, a joint portion 4b is arranged. Due to the joint portion 3b and the joint portion 4b, the first arm 3 and the second arm 4 are bent in a direction in which the suction cups 3d and 4d approach each other. That is, in the initial state or the state where the decompression is released, the suction surfaces 3e and 4e are set flush. With this configuration, the suction to the workpiece W1 can be stably performed, and the workpiece W1 can be stably placed at a desired moving location.

[0028] At a position between the joint portion 3b and the suction cup 3d in the first arm 3, a connecting portion 6 that connects the first arm 3 and the main body 2 is arranged. Also, at a position between the joint portion 4b and the suction cup 4d in the second arm 4, a connecting portion 7 that connects the second arm 4 and the main body 2 is arranged. With this configuration, the first arm 3 and the second arm 4 can be easily moved closer to each other in conjunction with the contraction operation of the main body 2. Moreover, the first arm 3 and the second arm 4 can be easily moved away from each other in conjunction with the expansion operation of the main body 2.

[0029] Subsequently, based on the examples shown in FIGS. 2 to 4, the usage mode of moving the workpiece W1 will be described below.

[0030] As shown in FIG. 2, in a workpiece assembly W in which workpieces W1, W2, ···, Wn (n is a natural number of 3 or more) are stacked in order from above, with respect to the workpiece W1 at the uppermost position, the vacuum pad 1A attached to the tip of the workpiece moving device 14 is lowered from above, and the pair of suction cups 3d and 4d are placed on the upper surface of the workpiece W1.

[0031] Following the state of FIG. 2, as shown in FIG. 3, the flow path switching valve 13 is switched to the negative position to depressurize the space portion 2a in the vacuum pad 1A, so that the suction pads 3d and 4d are adsorbed to the workpiece W1, the workpiece W1 is bent, and the vacuum pad 1A is lifted to separate the workpiece W1 from the other workpiece W2. By depressurizing and bending the workpiece W1, it can be easily separated from the other workpiece W2.

[0032] Following the state of FIG. 3, the workpiece W1 is moved to a desired moving location. Then, as shown in FIG. 4, the flow path switching valve 13 is switched to the positive position to release the depressurization of the space portion 2a in the vacuum pad 1A, thereby releasing the workpiece W1. By releasing the depressurization, the workpiece W1 returns from its self-weight or the state where it is bent in addition to its self-weight to the original flat state by the restoring force, and separates from the suction pads 3d and 4d and is placed at the desired moving location.

[0033] According to the present embodiment, it operates with a simple control mechanism and can adsorb and move sheet-like or film-like workpieces W1 one by one. The present embodiment does not require additional capital investment such as a complex control mechanism or a separation device. Therefore, it can be easily applied to various manufacturing facilities such as existing packaging facilities, printing facilities, and bookbinding facilities.

[0034] Subsequently, the configuration of the vacuum pad 1B of the second example will be described below.

[0035] (Second example) FIG. 6 is a schematic perspective view showing the vacuum pad 1B according to the present embodiment. FIGS. 7 to 9 are views showing the usage mode of the vacuum pad 1B. FIG. 10 is a longitudinal sectional view of the vacuum pad 1B.

[0036] As shown in FIG. 6, the vacuum pad 1B has a 180° rotationally symmetric shape around the axis P1. The second example will be mainly described with differences from the above-described first example.

[0037] As shown in FIG. 10, the telescopic part 5 is arranged on the axis P1 and has a bellows part 5b that contracts and expands in a direction symmetric with respect to the axis P1. The bellows part 5b is formed by continuously connecting a mountain part that protrudes downward and outward and a valley part that is recessed upward and inward. Two or more mountain parts are formed, and preferably, two or more and four or less mountain parts are formed. One more valley part is formed than the mountain part. As an example, three mountain parts are formed and four valley parts are formed. Instead of the bellows part 5b, it is also possible to adopt a configuration in which one downward mountain part arranged on the axis P1 is formed, and two upward valley parts are formed on both sides of the mountain part.

[0038] In the telescopic part 5 of the main body 2, a first arm 3 having a hollow part 3a communicating with the space part 2a and a second arm 4 having a hollow part 4a communicating with the space part 2a are arranged. As an example, in the telescopic part 5, constricted parts 5c are respectively formed above the first arm 3 and above the second arm 4. With this configuration, the operation in which the first arm 3 and the second arm 4 approach each other as the telescopic part 5 contracts is enlarged, so that the work W1 can be gently bent and separated from the other work W2 easily. And, since the operation in which the first arm 3 and the second arm 4 move away from each other as the telescopic part 5 expands is enlarged, the gently bent work W1 can be stably placed at a desired moving location.

[0039] Subsequently, based on the examples shown in FIGS. 7 to 9, the usage mode of moving the work W1 will be described below.

[0040] As shown in FIG. 7, in a work assembly W in which works W1, W2, ···, Wn (n is a natural number of 3 or more) are stacked in order from above, with respect to the work W1 at the uppermost position, the vacuum pad 1B attached to the tip of the work moving device 14 is lowered from above, and the pair of suction pads 3d and the suction pad 4d are placed on the upper surface of the work W1.

[0041] Following the state of FIG. 7, as shown in FIG. 8, the flow path switching valve 13 is switched to the negative position to reduce the pressure in the space portion 2a of the vacuum pad 1B, so that the suction pads 3d and 4d are adsorbed to the workpiece W1, the workpiece W1 is bent, and the vacuum pad 1B is lifted to separate the workpiece W1 from the other workpiece W2. By reducing the pressure and bending the workpiece W1, it can be easily separated from the other workpiece W2.

[0042] Following the state of FIG. 8, the workpiece W1 is moved to a desired moving location. Then, as shown in FIG. 9, the flow path switching valve 13 is switched to the positive position to release the pressure reduction in the space portion 2a of the vacuum pad 1B, thereby releasing the workpiece W1. By releasing the pressure reduction, the workpiece W1 returns from its self-weight or the state where it is bent in addition to its self-weight to the original flat state by the restoring force, and separates from the suction pads 3d and 4d and is placed at the desired moving location.

[0043] In the above example, the vacuum pad 1 configured to be attached to the external holder 9 has been described, but it is not limited to this example. In this embodiment, there may be a case where the vacuum pad 1 is provided with a holder, and it is also possible to use a vacuum pad 1 integrated with the holder. The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the present invention.

Explanation of Reference Numerals

[0044] 1, 1A, 1B Vacuum pads 2 Body, 2a Space portion, 2b Mounting portion, 2c Mounting hole 3 First arm, 3a Hollow portion, 3b Joint portion, 3c Thin-walled portion, 3d Suction pad, 3e Adsorbing surface 4 Second arm, 4a Hollow portion, 4b Joint portion, 4c Thin-walled portion, 4d Suction pad, 4e Adsorbing surface 5 Telescopic portion, 5a Partition portion, 5b Bellows portion, 5c Constricted portion 6 Connecting portion 7 Connecting portion 9 External holder 11 External vacuum source 12 Flow path 13 Flow path switching valve 14 Work transfer device Axis P1 W Work assembly Workpieces W1, W2, ···, Wn

Claims

1. A workpiece moving device used in moving a sheet-like or film-like workpiece includes a main body in which a space communicating with an external vacuum source is formed, and a pair of hollow first and second arms extending from the main body while communicating with the space, the main body having an attachment section to which an external holder communicating with the external vacuum source is attached, and an expandable section which contracts when the space is decompressed and expands when the space is released from the decompression. A vacuum pad characterized by:

2. A suction cup is provided at each of the tip of the first arm and the tip of the second arm, and a joint is provided at each of the middle of the first arm and the middle of the second arm, and the first arm and the second arm are bent by the joint in a direction in which the suction cups approach each other. The vacuum pad according to claim 1 .

3. An integral structure made of elastomer, elastic rubber, or a composite of these, with a 180° rotational symmetry shape around an axis 3. The vacuum pad according to claim 1 or 2.

4. The expandable portion is configured to have a partition portion disposed on the axis and partitioning the space portion, or the expandable portion is configured to have a bellows portion disposed on the axis and contracting and expanding in directions symmetrical with respect to the axis.

3. The vacuum pad according to claim 1 or 2.

5. The workpiece at the top of a workpiece assembly in which a plurality of workpieces are stacked is suctioned by the pressure reduction, while the workpiece is bent, and the workpiece is released by releasing the pressure reduction.

3. The vacuum pad according to claim 1 or 2.

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