Workpiece holding device

Abstract

Provided is a workpiece holding device capable of reliably holding even a heavy workpiece and removing the held workpiece without applying a load.　In the workpiece holding device, an adhesive holding material 2 having self-adhesiveness is attached to one surface of a belt-like sheet 1 capable of elastic deformation, the belt-like sheet 1 is locked to a pedestal block 5 having a locking part 4 while the adhesive holding material 2 is directed outward, and an integrating means is provided which integrates a base surface 5a of the pedestal block 5 and another surface 1a of the belt-like sheet 1 by bringing these into close contact with each other. When holding the workpiece, the pedestal block 5 and the belt-like sheet 1 are integrated by the integrating means, and a workpiece holding surface is formed to adhere and hold the workpiece. When removing the workpiece, the integrating of the pedestal block 5 and the belt-like sheet 1 is released, the base surface of the pedestal block and the other surface of the belt-like sheet are separated from each other, and the workpiece can be detached from the workpiece holding surface.

Description

Work holding device

[0001] This invention relates to a workpiece holding device that holds a workpiece using a self-adhesive adhesive holding material, and more particularly to a workpiece holding device that is capable of holding even a heavy workpiece and that can remove the held workpiece without applying a load to it.

[0002] When transporting or picking up various workpieces such as semiconductor wafers and glass substrates, generally, a vacuum chuck that holds the workpiece by vacuum suction or an electrostatic chuck that holds the workpiece by electrostatic suction is used.

[0003] However, vacuum chucks cannot be used in pressure-reducing devices. Furthermore, with thin, fragile workpieces, vacuum marks may remain after chucking, and in some cases, the workpiece may even be damaged. On the other hand, electrostatic chucks may not be able to hold certain workpiece materials, or may require a high voltage to increase the chucking force. Therefore, several alternative methods that can hold workpieces in a simple manner without being limited by the type of workpiece and without equipment constraints are being investigated.

[0004] For example, a device has been proposed in which adhesive tape wound on a supply roll is wound onto a take-up roll while unused adhesive tape with strong adhesive strength is constantly supplied, and two adhesive tapes are used to hold the workpiece by their adhesive surfaces adhering to the workpiece, and then a pressure pin is used to press the gap between the two adhesive tapes from above, pushing the held workpiece downward and peeling it off (see Patent Document 1).

[0005] In addition, an electronic component transfer head has been proposed in which an electronic component (workpiece) is adhered by pressing the adhesive surface of an adhesive tape from above with a pressing block, and then the pressing block is raised while holding the electronic component, and at that time, the periphery of the electronic component is abutted against a guide member to prevent the electronic component itself from rising, thereby peeling off the electronic component (see Patent Document 2).

[0006] Furthermore, a picking device has been proposed in which adhesive tape is supplied between a supply side tape holder and a recovery side tape holder to adhere a workpiece, and after the workpiece has adhered, an excitation rotor with an eccentric cam located above the adhesive area is moved up and down to shake off the workpiece and peel it off (see Patent Document 3).

[0007] On the other hand, a device has been proposed in which a workpiece is held by a holding means having an adhesive coating layer coated with an adhesive, and then, when the workpiece is to be released, a plurality of air chambers located above the holding means that can be inflated with air are inflated, thereby bending the holding means and separating the workpiece from the adhesive coating layer (see Patent Document 4).

[0008] In addition, a work transport device has been proposed in which a self-adhesive adhesive layer is laminated on the surface of an endless belt, which is then turned into a belt conveyor using a drive roller and a driven roller, and which transports workpieces adhesively held by the adhesive layer (see Patent Document 5).

[0009] Japanese Patent Laid-Open No. 2-190287 Japanese Patent Laid-Open No. 2001-85896 Japanese Patent Laid-Open No. 2018-176289 Japanese Patent Laid-Open No. 2014-509953 Japanese Patent Laid-Open No. 2014-162571

[0010] When using adhesive tape to hold a workpiece as described above, it is necessary to exert sufficient holding force on the workpiece. At the same time, it is also important to know how to separate the held workpiece.

[0011] For example, when using an adhesive tape in which an adhesive is applied to a tape substrate such as cellophane, the holding force (adhesion force) on the workpiece can be increased by increasing the adhesive surface (bonding surface) on the workpiece.

[0012] However, in order to peel off the adhesive tape adhered to the workpiece, various measures are required as described in the above-mentioned Patent Documents 1 to 3. Moreover, in doing so, a large load is applied to the workpiece.

[0013] On the other hand, unlike adhesive tapes coated with adhesive, when the workpiece is adhesively held in place by a self-adhesive adhesive holding material such as that described in Patent Document 5, or when a partially cross-linked silicone resin such as that mentioned in Patent Document 4 (paragraph 0033 of the specification) is used, the force required to peel the workpiece off is relatively small.

[0014] However, if the adhesive strength is weak, the type of workpiece that can be held is limited. In particular, depending on the weight of the workpiece, the adhesive holding surface that adheres the workpiece may bend or twist, causing the workpiece to fall. Therefore, there is a trade-off between increasing the adhesive holding strength of the workpiece and being able to separate the workpiece with as little load as possible.

[0015] Therefore, the inventors conducted extensive research into a means of securely holding the workpiece while also enabling it to be separated with as little stress as possible on the workpiece. As a result, they discovered that by attaching a self-adhesive adhesive holding material to an elastically deformable strip-shaped sheet and using this strip-shaped sheet in combination with a base block, all of the above problems could be solved, and they completed the present invention.

[0016] Therefore, an object of the present invention is to provide a work holding device that can securely hold even a heavy workpiece and can separate the held workpiece without placing a load on it.

[0017] In other words, the present invention is a work holding device that holds a work using a self-adhesive adhesive holding material, comprising: a strip-shaped sheet having the adhesive holding material attached to one surface thereof and capable of elastic deformation; a base block having a base surface; and an integration means for tightly adhering and integrating the base surface of the base block with the other surface of the strip-shaped sheet; when holding a work, the integration means integrates the base block and the strip-shaped sheet to form a work holding surface and adhesively hold the work; and when removing the work, the integration means releases the integration of the base block and the strip-shaped sheet, separates the base surface of the base block from the other surface of the strip-shaped sheet, and peels the work from the work holding surface.

[0018] The workpiece holding device of the present invention comprises a strip-shaped sheet having the adhesive holding material attached to one surface thereof and capable of elastic deformation, a base block having a base surface, and an integration means for tightly adhering and integrating the base surface of the base block with the other surface of the strip-shaped sheet.

[0019] When holding a workpiece, the base block and the strip-shaped sheet are integrated by the integration means, and the strip-shaped sheet is aligned with the base surface of the base block to form a workpiece holding surface. This prevents deformation of the elastically deformable strip-shaped sheet, and also enables the adhesive holding material attached to the strip-shaped sheet to abut against the workpiece with a workpiece holding surface that is flush with the workpiece, ensuring reliable adhesive holding of the workpiece.

[0020] On the other hand, when removing the workpiece, the integration of the base block and the strip-shaped sheet by the integration means is released, and the base surface of the base block is separated from the other surface of the strip-shaped sheet. In other words, by returning the adhesive holding material that forms the workpiece holding surface to a deformable state, it becomes possible to lift the strip-shaped sheet from the workpiece adhesively held on the workpiece holding surface, and the workpiece can be peeled off from the workpiece holding surface.

[0021] In this way, by attaching a self-adhesive adhesive holder to an elastically deformable strip-shaped sheet and combining this strip-shaped sheet with a base block, when holding a workpiece, the base block and the strip-shaped sheet are integrated to form a workpiece holding surface, which makes it possible to reliably hold even heavy workpieces. Furthermore, when removing the workpiece, the integration of the base block and the strip-shaped sheet by the integration means is released, and the base block and the strip-shaped sheet are separated, allowing the held workpiece to be easily separated without applying any load to the workpiece.

[0022] Here, the strip-shaped sheet need only be capable of elastic deformation so as to follow the attachment and detachment of the workpiece as described above, and there are no particular restrictions on the material, etc., but for example, it may be made of resin, such as a resin film, or metal, or it may be made of paper, cloth, etc.

[0023] Furthermore, the adhesive holding material is self-adhesive. This differs from commercially available adhesive tapes (adhesive tapes) in which an adhesive is applied to a substrate such as cellophane, and the adhesive holding material itself is adhesive (self-adhesive). Therefore, with adhesive tapes, once applied and peeled off from the target object (workpiece), the adhesive strength of the adhesive decreases, ultimately rendering the tape unusable. However, with self-adhesive adhesive holding materials, workpieces can be repeatedly held and peeled off. In this case, cleaning the surface allows for further repeated use.

[0024] Suitable examples of such self-adhesive adhesive retaining materials include those made of resins such as silicone rubber, ethylene-propylene-diene rubber (EPDM), butyl rubber, fluorine-based resins, urethane-based resins, acrylic resins, etc. Among these, those that can exert van der Waals forces, a type of intermolecular force, at the interface with the workpiece to be adhesively retained are preferred.

[0025] The base block preferably has a base surface along which the strip sheet is placed to form a workpiece holding surface, and also has a locking portion that can lock the strip sheet while the adhesive holding material attached to the strip sheet faces outward. The base block may be made of metal, resin, or other materials, but is not particularly limited.

[0026] Furthermore, the integration means may be any means capable of bringing the base surface of the base block and the other surface of the strip sheet into close contact with each other to form a workpiece holding surface, and capable of releasing this state to separate the base surface of the base block and the other surface of the strip sheet. While there are no particular limitations on the specific means, the following means are preferred.

[0027] In other words, the integration means is formed by an electromagnet attached to the base block and a strip-shaped sheet made of a magnetic material, and by supplying an excitation current to the electromagnet, the inner surface of the strip-shaped sheet can be brought into close contact with the base surface of the base block.

[0028] The integrating means is formed by a suction pump connected to the base block and a suction port that sucks the inner surface of the strip sheet, and the inner surface of the strip sheet and the base surface of the base block can be tightly attached by sucking air with the suction pump.In addition to these, for example, an electrostatic chuck may be provided on the base block side to generate an electrostatic attraction force and tightly attach the inner surface of the strip sheet to the base surface of the base block.

[0029] In the workpiece holding device of the present invention, when removing the workpiece, the workpiece may be peeled off from the workpiece holding surface while restricting the movement of the workpiece with a workpiece restricting means that restricts the movement of the workpiece toward the base block. More specifically, when removing the workpiece from the workpiece holding surface, the workpiece can be peeled off from the workpiece holding surface while pressing the upper surface of the workpiece with the workpiece restricting means, thereby making it possible to remove the workpiece more reliably.

[0030] Furthermore, as described above, the workpiece holding device of the present invention may be provided with a through-hole that penetrates from the base block to the strip-like sheet when the base block and the strip-like sheet are in close contact with each other to form the workpiece holding surface. That is, a through-hole is provided that penetrates from the top surface (the surface opposite the base surface) or side surface of the base block to the strip-like sheet, and the adhesive holding state of the workpiece on the workpiece holding surface is detected by observing the gas flow within this through-hole. For example, if gas leaks through the through-hole when a workpiece is held on the workpiece holding surface, this indicates that the workpiece is not in close contact with the workpiece holding surface.

[0031] The workpieces to be adhesively held by the workpiece holding device of the present invention are not particularly limited as long as they can be adhesively held by a self-adhesive adhesive holding material, and examples include semiconductor wafers, glass substrates, and materials made of various materials such as metal materials such as aluminum and stainless steel, and resin films, etc. Materials and parts used in manufacturing processes can also be adhesively held as workpieces.

[0032] According to the present invention, workpieces can be held with sufficient adhesive strength and can be separated without applying any load to the held workpieces. Therefore, even heavy workpieces can be held without dropping, and even thin and weak workpieces can be separated without scratching or damaging them.

[0033] Furthermore, since the workpiece holding device of the present invention adhesively holds the workpiece using a self-adhesive adhesive holding material, it is versatile and can be used for any type or shape of workpiece, and is not subject to any particular restrictions in terms of equipment. Therefore, it can be used in a wide range of applications, such as as a workpiece transport device for transporting various types of workpieces, or as part of a robot hand that picks up works.

[0034] FIG. 1 is an explanatory perspective view from above of a workpiece holding device according to the present invention. FIG. 2 is an explanatory side view of a workpiece holding device according to the present invention. FIG. 3 is an explanatory plan view from below of a workpiece holding device according to the present invention. FIG. 4(a) is a schematic explanatory view showing a case where a workpiece is adhesively held using the workpiece holding device, and FIG. 4(b) is a schematic explanatory view showing a case where the workpiece is removed. FIG. 5 is a schematic explanatory view showing how the adhesive holding state of a workpiece is observed using a through-hole that penetrates from the base block to the adhesive holder, where (a) shows a case where the workpiece is correctly held, and (b) shows a case where the workpiece is not correctly held. FIG. 6 is a schematic explanatory view showing a through-hole that penetrates from the base block to the adhesive holder, where (a) is a side view and (b) is a plan view from below. FIG. 7 is a schematic explanatory view showing a modified example of a through-hole that penetrates from the base block to the adhesive holder, where (a) is a side view and (b) is a plan view from below. 8A and 8B are schematic explanatory views showing another modified example of a through hole that penetrates from the base block to the adhesive holder, where (a) is a side view and (b) is a plan view from below.

[0035] The present invention will be specifically described below with reference to the drawings, although the present invention is not limited to these details.

[0036] Figures 1 to 3 show an example of a workpiece holding device according to the present invention. Fig. 1 is an explanatory perspective view of this workpiece holding device X from above. Fig. 2 is an explanatory side view, and Fig. 3 is an explanatory plan view from below. In this workpiece holding device X, a self-adhesive adhesive holder 2 is attached to one surface 1a of an elastically deformable strip-shaped sheet 1, and the strip-shaped sheet 1 is engaged with a base surface 5a of a base block 5 having engaging portions 4 on both ends, with the adhesive holder 2 facing outward.

[0037] Furthermore, two electromagnets 6 are embedded inside the base block 5, and by forming the strip sheet 1 from a magnetic material, they constitute an integration means for integrating the base surface 5a of the base block 5 with the inner surface 1b (the surface not having the adhesive holding material 2) of the strip sheet 1. In other words, by supplying an excitation current to the coil of the electromagnet 6 from a power source not shown, the inner surface 1b of the strip sheet 1 made of a magnetic material such as iron, stainless steel, or a resin sheet containing iron powder and the base surface 5a of the base block 5 can be brought into close contact with each other, forming a work holding surface S for holding a workpiece.

[0038] In this work holding device X, a base block 5 is housed inside a work holding portion 7 having a U-shaped cross section, and four support columns 8 are erected on the base block 5, penetrating the U-shaped work holding portion 7, with an upper plate 9 attached to the tips of the columns. Furthermore, upper and lower guides 10 that guide the up and down movement of the base block 5 are attached to both ends of the U-shaped work holding portion 7, and an air cylinder 11 is attached to the center of the U-shaped work holding portion 7. A rod 11a of the air cylinder 11 is fixed to the U-shaped work holding portion 7, and also passes through the base block 5, with the tip of the rod 11a also fixed to the strip-shaped sheet 1. During work removal (dechucking), which will be described later, the rod 11a, together with the U-shaped work holding portion 7, acts as a work restricting means for restricting movement of the work w toward the base block 5.

[0039] Here, the adhesive holding material 2 is made of silicone rubber, ethylene-propylene-diene rubber (EPDM), butyl rubber, fluorine-based resin, urethane-based resin, acrylic resin, or the like, and has self-adhesive properties that exhibit van der Waals forces, a type of intermolecular force. In this example, as shown in FIG. 3 , the workpiece holding device X has adhesive holding materials 2 provided at two locations on the outer surface 1a of the strip-shaped sheet 1. Furthermore, a non-adhesive rubber holding material 3, which has no adhesiveness, is provided between the two adhesive holding materials 2 and is aligned in thickness (height) with the adhesive holding materials 2. Furthermore, in this workpiece holding device X, non-adhesive holding materials 3 are also provided on both ends of the strip-shaped sheet 1. These adhesive holding materials 2 and non-adhesive holding materials 3 are aligned at the same height (flush) when the base block 5 and the strip-shaped sheet 1 are integrated by an integration means consisting of the electromagnet 6 and the strip-shaped sheet 1 to form the workpiece holding surface S.

[0040] To hold a workpiece using this workpiece holding device X, first, as shown in FIG. 4( a), an excitation current is passed through the coil of the electromagnet 6 constituting the integration means, causing the inner surface 1b of the magnetic strip 1 to come into close contact with the base surface 5a of the base block 5. Next, in this state, the workpiece w is brought relatively close to the workpiece holding surface S, and the adhesive holding material 2 on the workpiece holding surface S adhesively holds the workpiece w. At this time, the base block 5 may press the adhesive holding material 2 on the workpiece holding surface S against the workpiece w via the upper plate 9. Alternatively, the integration means may be used to integrate the base block 5 and the strip 1, while the workpiece w is brought relatively close to the workpiece holding surface S to adhesively hold the workpiece w. Alternatively, the integration means may be used to bring the strip 1 relatively close to the workpiece w and abut it against it, and then integrate the base block 5 and the strip 1.

[0041] On the other hand, when removing the workpiece, as shown in FIG. 4( b), first, the integration between the base block 5 and the strip sheet 1 by the integration means is released. Next, the air cylinder 11 is operated to push up the upper plate 9, separating the base surface 5a of the base block 5 from the other surface 1b of the strip sheet 1. That is, when the air cylinder 11 operates (the rod of the air cylinder 11 is extended), the upper plate 9 is pushed up by the rod of the air cylinder 11, causing the base block 5 to rise, and the strip sheet 1 to rise at the engagement portion of the base block. At this time, the center of the strip sheet 1 is pressed against the workpiece w by the rod 11a fixed to the U-shaped workpiece pressing portion 7. Similarly, the tip of the U-shaped workpiece pressing portion 7 presses down on the top surface of the workpiece w, restricting the movement of the workpiece w toward the base block 5. As a result, both ends of the strip sheet 1 are rolled up, and the workpiece w is peeled off from the workpiece holding surface S. In this example of the work holding device X, the rod 11a is located approximately in the center of the strip sheet 1, but for example, the air cylinder 11 may be provided on the end side of the strip sheet so that one side of the strip sheet 1 is pressed while the remaining end is rolled up, thereby peeling the work off the work holding surface S.

[0042] In this example, as an integration means for integrating the base block 5 of the workpiece holding device X with the strip sheet 1, the strip sheet 1 is formed of a magnetic material and an electromagnet 6 is attached to the base block 5 so that the inner surface 1b of the strip sheet 1 and the base surface of the base block 5 can be brought into close contact with each other. However, other methods may also be used, for example, by forming suction holes in the base surface 5a of the base block 5 and using a suction pump or the like to attract the inner surface 1b of the strip sheet 1 and the base surface 5a of the base block 5. Also, an attraction electrode may be incorporated in the base block 5 to generate an electrostatic attraction force on the base surface 5a, so that the inner surface 1b of the strip sheet 1 and the base surface of the base block 5 can be brought into close contact with each other.

[0043] Furthermore, in the present invention, a through-hole 12 may be provided that penetrates from the base block 5 to the band-shaped sheet 1 when the base block 5 and the band-shaped sheet 1 are in close contact with each other to form the workpiece holding surface S. This allows the adhesive holding state of the workpiece W on the workpiece holding surface S to be detected by observing the gas flow in the through-hole 12. For example, as shown in FIG. 5 , with the workpiece W held on the workpiece holding surface S, a test gas is supplied from the base block 5 to the inlet of the through-hole 12 at a supply pressure P. After confirming the initial pressure, the pressure is continuously observed over time. If the gas pressure remains the same as the initial pressure (no leaks), it is determined that the workpiece W is properly adhesively held on the workpiece holding surface S (FIG. 5( a)). On the other hand, if the gas pressure changes from the initial pressure (if the pressure drops by the amount of a leak), it is determined that the workpiece W is not properly adhesively held on the workpiece holding surface S (FIG. 5( b)).

[0044] While Figure 5 above shows an example in which a test gas is supplied, the pressure can also be checked by exhausting the air from the through-hole 12 with a pump. If there is no leak, the ultimate vacuum pressure will be constant, and it will be determined that the workpiece w is properly adhesively held on the workpiece holding surface S (Figure 5(a)). On the other hand, if the ultimate vacuum pressure is low (if the pressure increases by the amount of the leak), it will be determined that the workpiece w is not properly adhesively held on the workpiece holding surface S (Figure 5(b)). In addition to the pressure determination method, a similar determination can also be made by monitoring the flow rate with a flow meter.

[0045] In the previous example of the workpiece holding device X, through-holes 12 are provided from the side surface of the base block 5 to the adhesive holder 2 of the strip sheet 1. However, as shown in FIG. 6, for example, the through-holes 12 may be configured to penetrate the thickness direction of the base block 5. Alternatively, the adhesive holder 2 on the strip sheet 1 side may be configured to include a first adhesive holder 2a and a second adhesive holder 2b surrounding it, with a closed gas flow path formed between the first and second adhesive holders 2a and 2b. Furthermore, as shown in FIG. 7, multiple through-holes 12 may be provided to penetrate to the adhesive holder 2 attached to the strip sheet 1 in accordance with the planar shape of the adhesive holder 2. Furthermore, as shown in FIG. 8, the through-holes 12 may be connected to each other within the base block 5 so that the number of outlets of the through-holes 12 on the strip sheet 1 side does not match the number of inlets of the through-holes 12 on the base block 5 side.

[0046] Experimental Example: An experiment was conducted to adhesively hold a test workpiece using the workpiece holding device X described above. Here, the strip-shaped sheet 1 was made of elastically deformable SUS410 (martensitic stainless steel: ferromagnetic), measuring 30 mm wide, 130 mm long, and 1 mm thick. The adhesive holding material 2 consisted of two self-adhesive adhesive holding materials measuring 30 mm wide, 30 mm long, and 1 mm thick, and one non-adhesive holding material 3 measuring 10 mm wide, 30 mm long, and 1 mm thick. These were aligned at d = 5 mm on one side 1a of the strip-shaped sheet 1 and bonded with an acrylic adhesive, as shown in Figure 3 above. Two non-adhesive holding materials 3 measuring 6 mm wide, 34 mm long, and 1 mm thick were also prepared and bonded to both ends of the strip-shaped sheet 1 with an acrylic adhesive, so that the adhesive holding materials 2 and the non-adhesive holding materials 3 were aligned at the same height. The adhesive holding material 2 has self-adhesive properties that allow it to adhesively hold the test workpiece in place by the van der Waals force of the surface when it comes into contact with the surface of the test workpiece.

[0047] Three types of workpieces (all made of aluminum alloy) were prepared as the workpieces to be adhesively held: test workpiece w1, 200 mm wide x 200 mm long x 10 mm thick, and weighing 1.1 kg; test workpiece w2, 250 mm wide x 250 mm long x 10 mm thick, and weighing 1.7 kg; and test workpiece w3, 300 mm wide x 450 mm long x 10 mm thick, and weighing 3.7 kg. These were placed on a flat table and adhesively held using workpiece holding device X, and the presence or absence of falling was confirmed as follows.

[0048] First, to adhesively hold a test workpiece using the workpiece holding device X, the rod of the air cylinder 11 was retracted, the adhesive holding material 2 of the strip sheet 1 was brought into contact with the surface of the test workpiece, the upper plate 9 was pressed against the base block 5, and then DC 24V was supplied to the two electromagnets 6 (the electromagnets were turned on). This caused the other surface 1b of the elastically deformable strip sheet 1 to tightly adhere to the base surface 5a of the base block 5 (suppressing deformation of the elastically deformable strip sheet 1), forming a workpiece holding surface P and enabling adhesive holding of the test workpiece. The electromagnet 6 had a diameter of 15 mm and a length of 15 mm, and had a surface magnetic flux density of approximately 19 mT when supplied with DC 24V and an adhesive force of 25 N when supplied with DC 24V.

[0049] In this state, the workpiece holding device X was lifted approximately 5 cm and maintained for 300 seconds, and the test workpiece was evaluated as ◯ if it was able to be held by the workpiece holding device X without dropping during that time, and x if it fell. Also, for comparison, the test workpiece was evaluated for dropping when the workpiece holding device X was lifted in the same manner as above without supplying current (DC 24 V) to the electromagnet 6 (the electromagnet was turned off). The results are shown in Table 1.

[0050] Although not subject to evaluation in this experimental example, when removing the test workpiece held on the workpiece holding surface P, the lifted workpiece holding device X was lowered to place the test workpiece on the table. The supply of current (24V DC) to the two electromagnets 6 was then stopped, releasing the integration between the base block 5 and the strip sheet 1. This rendered the strip sheet 1 deformable. Then, the air cylinder 11 was pushed out with an air supply pressure of approximately 0.3 MPa, moving the upper plate 9 upward and lifting the base surface 5a of the base block 5. The non-adhesive holding material 3 attached to the center of one surface 1a of the strip sheet 1 remained pressed against the test workpiece, deforming the strip sheet 1 and separating the base surface 5a of the base block 5 from the other surface 1b of the strip sheet 1. The adhesive holding material 2 was then peeled off from the surface of the test workpiece by being lifted from the end of the strip sheet 1, and the test workpiece was removed. The air cylinder 11 was a double-acting air cylinder with a cylinder tube diameter of 12 mm and a stroke of 10 mm, and its operation was controlled by an electromagnetic valve.

[0051]

[0052] As shown in Table 1, the workpiece holding device X of the present invention was able to adhesively hold all three types of test workpieces w1 to w3 of different weights. On the other hand, when current was not supplied to the electromagnet 6 and the base block 5 and the strip-shaped sheet 1 were not integrated, the test workpieces w1 to w3 could not be properly held. Of these, the test workpieces w1 and w2 could be lifted from the table together with the workpiece holding device X, but they fell within 20 seconds. Furthermore, the test workpiece w3 could not even be lifted from the table using the workpiece holding device X. In other words, with the workpiece holding device X of the present invention, the elastically deformable strip-shaped sheet was integrated with the base block, suppressing its deformation, thereby suppressing deformation of the adhesive holding material itself, and thus enabling even heavy workpieces to be reliably adhesively held.

[0053] As described above, according to the present invention, it is possible to hold a workpiece with sufficient adhesive force and to separate the held workpiece without applying a load to it. Moreover, since the workpiece holding device of the present invention adhesively holds a workpiece by the van der Waals force of the surface, it is versatile and can be used for any type or shape of workpiece. For example, it can be used as a workpiece transport device for transporting various types of workpieces, as part of a robot hand that picks up works, or for fixing works, and can be used in a wide range of applications.

[0054] 1: Strip-shaped sheet, 2: Adhesive holding material, 3: Non-adhesive holding material, 4: Locking portion, 5: Base block, 5a: Base surface, 6: Electromagnet, 7: Workpiece holding portion, 8: Support, 9: Upper plate, 10: Upper and lower guides, 11: Air cylinder, 11a: Rod, 12: Through hole

Claims

1. A workpiece holding device that holds a workpiece using a self-adhesive adhesive holding material, a belt-shaped sheet having the adhesive holding material attached to one surface thereof and capable of elastic deformation; a base block having a base surface; and an integration means for tightly contacting and integrating the base surface of the base block and the other surface of the belt-shaped sheet, the integration means is formed by an electromagnet attached to the base block and the strip-shaped sheet made of a magnetic material, and by supplying an excitation current to the electromagnet, the inner surface of the strip-shaped sheet and the base surface of the base block can be brought into close contact with each other; When holding the workpiece, the base block and the strip-shaped sheet are integrated by the integration means to form a workpiece holding surface and adhesively hold the workpiece; This work holding device is characterized in that, when removing the workpiece, the integration between the base block and the strip-shaped sheet by the integration means is released, the base surface of the base block is separated from the other surface of the strip-shaped sheet, and the workpiece is pulled off from the work holding surface.

2. A workpiece holding device that holds a workpiece using a self-adhesive adhesive holding material, a belt-shaped sheet having the adhesive holding material attached to one surface thereof and capable of elastic deformation; a base block having a base surface; and an integration means for tightly contacting and integrating the base surface of the base block and the other surface of the belt-shaped sheet, the integration means is formed by a suction pump connected to the base block and a suction port that sucks the inner surface of the strip-shaped sheet, and by sucking air with the suction pump, the inner surface of the strip-shaped sheet can be brought into close contact with the base surface of the base block; When holding the workpiece, the base block and the strip-shaped sheet are integrated by the integration means to form a workpiece holding surface and adhesively hold the workpiece; This work holding device is characterized in that, when removing the workpiece, the integration between the base block and the strip-shaped sheet by the integration means is released, the base surface of the base block is separated from the other surface of the strip-shaped sheet, and the workpiece is pulled off from the work holding surface.

3. A workpiece holding device that holds a workpiece using a self-adhesive adhesive holding material, a belt-shaped sheet having the adhesive holding material attached to one surface thereof and capable of elastic deformation; a base block having a base surface; and an integration means for tightly contacting and integrating the base surface of the base block and the other surface of the belt-shaped sheet, the integration means is an electrostatic chuck provided on the base block, and an electrostatic attraction force is generated by the electrostatic chuck, thereby making it possible to bring the inner surface of the belt-shaped sheet into close contact with the base surface of the base block; When holding the workpiece, the base block and the strip-shaped sheet are integrated by the integration means to form a workpiece holding surface and adhesively hold the workpiece; This work holding device is characterized in that, when removing the workpiece, the integration between the base block and the strip-shaped sheet by the integration means is released, the base surface of the base block is separated from the other surface of the strip-shaped sheet, and the workpiece is pulled off from the work holding surface.

4. 4. The workpiece holding device according to claim 1, wherein when removing the workpiece, the workpiece is peeled off from the workpiece holding surface while being restricted by a workpiece restricting means that restricts movement of the workpiece toward the base block.

5. A workpiece holding device as described in any one of claims 1 to 3, wherein the base block has a locking portion, and the strip-shaped sheet is locked to the locking portion of the base block with the surface having the adhesive retaining material facing outward.

6. A work holding device as described in any one of claims 1 to 3, wherein when the base block and the strip-shaped sheet are in close contact to form a work holding surface, a through hole is provided that passes from the base block to the adhesive holding material, and by observing the gas flow rate or pressure within the through hole, the adhesive holding state of the work on the work holding surface can be detected.