JP7701833B2 - Grip device and industrial robot - Google Patents

Description

The present invention relates to a gripping device and an industrial robot.

A gripping device with a bag-shaped gripping body is known as a gripping device intended to grip a workpiece (Patent Document 1). In the gripping device according to Patent Document 1, the gripping body has a palm portion and multiple finger portions that protrude from the periphery of the palm portion and fall toward the palm portion by deforming the palm portion in the thickness direction. By reducing the pressure inside the gripping body, the palm portion deforms in the thickness direction, and the multiple finger portions elastically deform so as to fall toward the palm portion. As a result, the multiple finger portions come into contact with the surface of the workpiece and grip the workpiece.

JP 2017-185553 A

In the gripping device disclosed in Patent Document 1, when multiple fingers are tilted down to grip a workpiece with the multiple fingers, damage such as dents may occur to the workpiece. One method for gripping the workpiece without leaving dents on the workpiece is to make the fingers flexible to improve their ability to conform to the shape of the workpiece. However, making the fingers flexible reduces the gripping force, and there is a risk that the workpiece may fall off the gripping device when the gripping device is moved while gripping the workpiece.

The present invention aims to provide a gripping device and industrial robot that can prevent damage to a workpiece while maintaining gripping force.

The gripping device according to the present invention comprises a palm portion, a number of finger portions protruding from the periphery of the palm portion and collapsing toward the palm portion by deforming the palm portion in the thickness direction, and an elastic portion that has a higher flexibility than the finger portions and is provided on the finger portions so as to be deformable in the direction opposite to the direction in which the finger portions collapse.

The industrial robot according to the present invention is equipped with the above-mentioned gripping device.

According to the present invention, by providing an elastic part, the elastic part can grasp the workpiece by clamping it while following the shape of the workpiece, so that it is possible to prevent damage to the workpiece while maintaining the gripping force.

FIG. 1 is a schematic diagram illustrating an example of an industrial robot to which a gripping device according to an embodiment is applied. FIG. 2 is a partial cross-sectional view showing a gripping device according to an embodiment. FIG. 2 is a partial cross-sectional view of the gripping device according to the embodiment, showing a state in which the palm portion is deformed in the thickness direction. 4 is a cross-sectional view taken along line IV-IV shown in FIG. 2. FIG. 2 is a partial cross-sectional view showing a state in which the gripping device according to the embodiment is used. FIG. 2 is a perspective view showing a state in which the gripping device according to the embodiment is used. FIG. 11 is a cross-sectional view of a gripping device according to a first modified example of the embodiment. FIG. 11 is a cross-sectional view of a gripping device according to a second modified example of the embodiment. FIG. 11 is a cross-sectional view of a gripping device according to a third modified example of the embodiment. FIG. 11 is a cross-sectional view of a gripping device according to a fourth modified example of the embodiment. FIG. 13 is a cross-sectional view of a gripping device according to a modified example 5 of the embodiment. FIG. 13 is a cross-sectional view of a gripping device according to a sixth modified example of the embodiment. FIG. 13 is a partial cross-sectional view showing a state in which a gripping device according to a sixth modified example of the embodiment is used. FIG. 13 is a cross-sectional view of a gripping device according to a seventh modified example of the embodiment. FIG. 23 is a cross-sectional view of a gripping device according to an eighth modified example of the embodiment.

The following describes in detail the embodiments of the present invention with reference to the drawings. The embodiments and modifications described below are examples of the present invention, and the present invention is not limited thereto. In the following description of the embodiments and modifications, similar configurations are given similar reference numerals, and descriptions will be omitted as appropriate.

1. Embodiment (Overall Configuration)
1 shows the configuration of an industrial robot 12 to which a gripping device 10A according to this embodiment is applied. The industrial robot 12 is an orthogonal robot, and includes a rail 14, a moving body 16 that moves along the rail 14, and an air cylinder 18 fixed to the moving body 16. The rail 14 is provided so as to be movable in the Y-axis direction in the drawing.

The air cylinder 18 has a cylinder tube 19 and a piston rod 20 that is provided so as to be movable forward and backward relative to the cylinder tube 19. Pipes 21 and 22 are provided to the cylinder tube 19. The piston rod 20 can be moved forward and backward relative to the cylinder tube 19 by supplying and discharging gas through the pipes 21 and 22. A gripping device 10A is provided at the tip of the piston rod 20 via a detachable part 24 that is connected to an adapter plate 23. The adapter plate 23 is fixed to the tip of the piston rod 20 by a bolt (not shown).

The industrial robot 12 can grasp the workpiece W placed on the horizontal base 26 with the gripping device 10A and move it in the X-axis, Y-axis, and Z-axis directions.

Figure 2 shows a partial cross-sectional view of the gripping device 10A. Figure 2 shows the gripping device 10A removed from the detachable part 24. The gripping device 10A has a gripping body 28 that is attached to the piston rod 20 via the detachable part 24. The gripping body 28 can be made of a material that is airtight, elastic, and flexible, such as natural rubber, synthetic rubber, or various elastomers. The material of the gripping body 28 does not necessarily have to be a single type of material, and may be a composite material made by combining different types of materials. The hardness of the gripping body 28 measured in accordance with the durometer hardness test (type A) of JIS K6253 is preferably about 60 to 90.

The grip body 28 has a palm portion 30 and multiple finger portions 32A protruding from the periphery of the palm portion 30. The palm portion 30 is generally disk-shaped. The finger portions 32A are formed integrally with the palm portion 30, and two finger portions 32A are provided to sandwich the palm portion 30. A predetermined distance is formed between the finger portions 32A. Three or more finger portions 32A may be provided radially to surround the palm portion 30.

The inner surface 34 of the finger portion 32A is formed integrally with the palm portion 30. The finger portion 32A is solid. The material of the finger portion 32A may be the same as that of the palm portion 30 or a different material, and it does not need to be uniform, but may be a composite material that combines different materials or may contain additives such as fillers.

When a force is applied to the palm portion 30 and the palm portion 30 is deformed in the thickness direction (Z direction), the inner surface 34 of the grip body 28 is pulled by the palm portion 30. As a result, as shown in FIG. 3, the finger portion 32A is elastically deformed so as to fall toward the palm portion 30.

The force that deforms the palm portion 30 in the thickness direction (Z direction) is applied to the palm portion 30 using gas. The deformation of the palm portion 30 using gas will be specifically described with reference to Figures 2 and 3.

The grip body 28 is formed in a bag shape with an opening on the side opposite to the surface on which the palm portion 30 and the finger portion 32A are formed. The opening of the grip body 28 is sealed by the case 40, and an internal space 29 is formed by the inner surface of the grip body 28 and the case 40. The grip body 28 and the case 40 are fixed together by a band 41 wrapped around the outer circumference of the grip body 28.

The case 40 is preferably made of a metal such as stainless steel, or a hard resin such as plastic. The case 40 has a tubular portion 42, an upper portion 43 provided at the upper end of the tubular portion 42, and a joint 44 provided on the upper portion 43. The tubular portion 42 is a cylindrical member. The upper portion 43 is a disk-shaped member. The tubular portion 42 and the upper portion 43 are formed integrally. A through hole 45 is provided in the center of the upper portion 43, penetrating it in the thickness direction. The joint 44 communicates with the through hole 45. The joint 44 is screwed to the upper portion 43 via a sealing material 46. The joint 44 is connected to the detachable portion 24 in a one-touch manner so as to be freely attached and detached.

The detachable part 24 is a one-touch joint, one end of which is connected to the adapter plate 23 and the other end of which is connected to the joint 44. The detachable part 24 is connected to the joint 44 when the joint 44 is inserted in the insertion direction, and is disconnected from the joint 44 by pushing the release part 47 in the insertion direction. The detachable part 24 is not limited to a one-touch joint, and may be a joint that is connected to the joint 44 by a screw.

The detachable part 24 has an intake and exhaust port 48 on its periphery. The intake and exhaust port 48 is connected to one end of a pipe (not shown). The other end of the pipe is connected to a vacuum pump, for example, via a three-way valve. The three-way valve has a vacuum port, an intake and exhaust port, and an air release port, with the vacuum port connected to the vacuum pump, the intake and exhaust port connected to the gripping device 10A, and the air release port connected to the atmospheric pressure space. Through the pipe connected to the intake and exhaust port 48, gas flows from the internal space 29 to the vacuum pump and from the atmospheric pressure space to the internal space 29. The detachable part 24 is fixed to the adapter plate 23 by screwing a bolt into the adapter plate 23 through a mounting hole (not shown) provided on the top surface.

When gas is sucked from the internal space 29 of the grip body 28 using a vacuum pump, the palm portion 30 is pulled in the thickness direction (Z direction) together with the gas in the internal space 29. In other words, a force that deforms the palm portion 30 in the thickness direction (Z direction) is applied to the palm portion 30. In this way, in this embodiment, the gas is used to deform the palm portion 30 in the thickness direction.

The gripping device 10A includes an elastic portion 50A that has higher flexibility than the finger portion 32A. The elastic portion 50A is provided on the finger portion 32A so that it can deform in the direction opposite to the direction in which the finger portion 32A falls. The deformation of the elastic portion 50A will be described in detail with reference to FIG. 4.

Figure 4 shows a cross-sectional view taken along line IV-IV in Figure 2. Finger portion 32A has a base 35 extending from palm portion 30 (see Figure 2) and a pair of protrusions 36A, 37A protruding from base 35. The external shapes of base 35 and pair of protrusions 36A, 37A can be selected as appropriate, and may be, for example, a rectangular parallelepiped, a square prism, a triangular prism, a cylinder, a square pyramid, a truncated square pyramid, a truncated cone, etc.

The pair of protrusions 36A, 37A are spaced apart from each other when viewed in the direction in which the finger portion 32A falls, and a cavity is formed between the pair of protrusions 36A, 37A.

The elastic portion 50A is formed in a bag shape and is placed over the finger portion 32A so as to cover the pair of protrusions 36A, 37A. Because there is a cavity between the pair of protrusions 36A, 37A, the elastic portion 50A can be deformed to fit between the pair of protrusions 36A, 37A. In this way, the elastic portion 50A can be deformed in the opposite direction to the direction in which the finger portion 32A falls.

Figure 5 shows a partial cross-sectional view of the gripping device 10A when gripping a workpiece W, and Figure 6 shows an oblique view of the gripping device 10A when gripping a workpiece W. When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32A fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W in a pinched manner. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

The ability to conform to the shape of the workpiece W is influenced by a combination of the material properties (e.g., flexibility, viscoelasticity, and hardness) and mechanical structure (e.g., thickness and structures that contribute to deformation, such as bellows) of the elastic portion 50A. The material properties and mechanical structure of the elastic portion 50A can be appropriately selected according to the required conformability.

The surface of the elastic part 50A may be provided with a non-slip surface such as a rib. In this case, the friction between the elastic part 50A and the workpiece W is improved, and the workpiece W can be prevented from falling off the gripping device 10A.

When the elastic part 50A is removed from the finger part 32A, it is smaller than the outer shape of the finger part 32A and is placed over the finger part 32A in an expanded state. This makes it easy to remove the elastic part 50A. Therefore, if the elastic part 50A is damaged, for example, the elastic part 50A can be easily replaced.

A ring groove 38 is formed on the outer peripheral surface of the base 35 of the finger portion 32A, and the elastic portion 50A is hooked onto the ring groove 38. This prevents the elastic portion 50A from falling off the finger portion 32A, and more reliably prevents the workpiece W from falling off the gripping device 10A.

(Action and Effects)
The operation and effects of the industrial robot 12 equipped with the gripping device 10A configured as above will be described. Note that the conditions shown below are examples. As shown in Fig. 1, the industrial robot 12 has an origin in a state in which the piston rod 20 is retracted into the cylinder tube 19 and the air cylinder 18 is contracted. In the initial state of the gripping device 10A, the pressure in the internal space 29 (see Fig. 2) in the gripping body 28 is atmospheric pressure. That is, the three-way valve is in a state in which the supply and exhaust port is blocked from the vacuum port and connected to the atmosphere release port.

The industrial robot 12 positions the gripping device 10A on the vertical line of the workpiece W placed on the base 26 by moving the moving body 16 along the rail 14. Next, the industrial robot 12 extends the air cylinder 18 by advancing the piston rod 20 from the cylinder tube 19 until the finger portion 32A reaches the side of the workpiece W.

The three-way valve is then switched so that the supply and exhaust port is disconnected from the atmosphere release port and connected to the vacuum port. This causes the gripping device 10A to suck in the gas from within the gripping body 28 through the piping, reducing the pressure in the internal space 29 in the gripping body 28 to, for example, -0.03 MPa or less.

As shown in FIG. 5, the palm portion 30 is deformed in the thickness direction as if being sucked in. As the palm portion 30 deforms in the thickness direction, the inner surface 34 of the finger portion 32A is pulled toward the center of the palm portion 30. This causes the finger portion 32A to elastically deform so as to fall toward the palm portion 30. This causes the elastic portion 50A to come into contact with the surface of the workpiece W. As described above, the gripping device 10A grips the workpiece W by reducing the pressure inside the gripping body 28.

Then, the industrial robot 12 can lift the workpiece W from the base 26 by retracting the piston rod 20 into the cylinder tube 19 and contracting the air cylinder 18. Furthermore, the industrial robot 12 can freely move the workpiece W in the horizontal direction by the moving body 16 moving along the rail 14 and the rail 14 moving in the Y-axis direction.

After moving to the desired location, the industrial robot 12 extends the air cylinder 18 by advancing the piston rod 20 from the cylinder tube 19 until the workpiece W comes into contact with the base 26. Next, the three-way valve is switched to a state in which the supply and exhaust port is disconnected from the vacuum port and connected to the atmosphere release port. This causes gas to flow from the atmosphere release port through the piping into the internal space 29 of the gripping body 28. As the pressure in the internal space 29 of the gripping body 28 returns to atmospheric pressure, the palm portion 30 is pushed out and returns to its original state. As the palm portion 30 returns to its original state, the fingers 32A open and release the workpiece W.

Next, the industrial robot 12 retracts the piston rod 20 into the cylinder tube 19 and contracts the air cylinder 18, thereby detaching the gripping device 10A from the workpiece W. In this way, the industrial robot 12 can move the workpiece W placed on the base 26 to the desired position by gripping it with the gripping device 10A.

The gripping device 10A is provided with an elastic portion 50A, so that as the finger portion 32A falls toward the palm portion 30, the elastic portion 50A deforms to follow the shape of the workpiece W, gripping the workpiece W in a pinched manner. This makes it possible to prevent damage to the workpiece W while maintaining the gripping force.

The gripping device 10A is particularly suitable for gripping multiple objects in sequence that are soft, fragile, and not uniform in shape, such as food products.

2. Modification 1
A gripping device 10B according to a first modified example of the above embodiment will be described with reference to Fig. 7. Fig. 7 shows a cross-sectional view of the gripping device 10B corresponding to Fig. 4 .

In the first modification, the elastic portion 50B is different from the above embodiment in that it is not placed over the finger portion 32A, but is stretched between the pair of protrusions 36A, 37A like a paddle. In the first modification, the elastic portion 50B has higher flexibility than the finger portion 32A, and is provided on the finger portion 32A so that it can deform in the opposite direction to the direction in which the finger portion 32A falls. Although not shown, when the workpiece W is placed between the elastic portions 50B and the palm portion 30 is deformed in the thickness direction, the finger portion 32A falls toward the palm portion 30 and the elastic portion 50B deforms while following the shape of the workpiece W, and grips the workpiece W by pinching it. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

The elastic portion 50B may be formed integrally with the pair of protrusions 36A, 37A.

In the first modification, the material properties and mechanical structure of the elastic portion 50B can be appropriately selected according to the required conformity. The surface of the elastic portion 50B may be provided with a non-slip surface such as a rib.

3. Modification 2
A gripping device 10C according to a second modified example of the above embodiment will be described with reference to Fig. 8. Fig. 8(a) shows a cross-sectional view of the gripping device 10C corresponding to Fig. 4, and Fig. 8(b) shows a cross-sectional view taken along line VIIB-VIIB shown in Fig. 8(a).

In the second modification, the elastic portion 50A in the above embodiment and the elastic portion 50B in the first modification are provided. That is, the gripping device 10C has the elastic portion 50B as a first elastic membrane attached to the finger portion 32A, and the elastic portion 50A as a second elastic membrane superimposed on the elastic portion 50B. In the second modification, when the workpiece W is placed between the elastic portions 50A and the palm portion 30 is deformed in the thickness direction, the finger portion 32A falls toward the palm portion 30 and the elastic portions 50A and 50B deform while following the shape of the workpiece W, and grip the workpiece W by pinching it. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

In the example shown in FIG. 8, a gap is provided between the elastic portion 50A and the elastic portion 50B, but the elastic portion 50A and the elastic portion 50B may be in contact with each other. When the elastic portion 50A and the elastic portion 50B are in contact with each other, the elastic portion 50A and the elastic portion 50B may be bonded to each other entirely or locally in a pattern. When locally bonded, a pattern may be provided on the surface of the elastic portion 50A to match the shape of the bonded portion.

4. Modification 3
A gripping device 10D according to a third modified example of the above embodiment will be described with reference to Fig. 9. Fig. 9(a) shows a cross-sectional view of the gripping device 10D corresponding to Fig. 4, and Fig. 9(b) shows a cross-sectional view taken along line VIIIB-VIIIB shown in Fig. 9(a).

In the third modification, the finger portion 32D has a columnar portion 36D extending from the base portion 35 and a plate-like portion 37D provided at the tip of the columnar portion 36D, instead of the pair of protrusions 36A, 37A (see FIG. 4, etc.) of the finger portion 32A in the above embodiment. The plate-like portion 37D is formed, for example, in a circular shape.

The columnar portion 36D supports the plate-shaped portion 37D away from the base portion 35. The cross section of the columnar portion 36D is smaller than the cross sections of the base portion 35 and the plate-shaped portion 37D, and a cavity is formed between the base portion 35 and the plate-shaped portion 37D. In other words, a cavity is formed around the columnar portion 36D.

The elastic portion 50A is placed over the finger portion 32D so as to cover the columnar portion 36D and the plate portion 37D. Because there is a cavity between the base portion 35 and the plate portion 37D, the elastic portion 50A can be deformed to enter between the columnar portion 36D and the plate portion 37D. In this way, the elastic portion 50A can be deformed in the direction opposite to the direction in which the finger portion 32D falls.

When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32D fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it were pinched. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

5. Modification 4
A gripping device 10E according to a fourth modified example of the above embodiment will be described with reference to Fig. 10. Fig. 10 shows a cross-sectional view of the gripping device 10E corresponding to Fig. 4 .

In the fourth modification, the finger portion 32E has a pair of protrusions 36E, 37E protruding from the base portion 35, and a columnar portion 39E provided between the pair of protrusions 36E, 37E. The columnar portion 39E extends from the base portion 35 along the pair of protrusions 36E, 37E. The protrusions 36E and the columnar portion 39E are spaced apart from each other when viewed in the direction in which the finger portion 32E falls. Similarly, the protrusions 37E and the columnar portion 39E are spaced apart from each other. In other words, cavities are formed between the protrusions 36E and the columnar portion 39E, and between the protrusions 37E and the columnar portion 39E.

The elastic portion 50A is placed over the finger portion 32E so as to cover the pair of protrusions 36E, 37E and the columnar portion 39E. Because there is a cavity between the protrusion 36E and the columnar portion 39E, and between the protrusion 37E and the columnar portion 39E, the elastic portion 50A can be deformed to enter between the protrusion 36E and the columnar portion 39E, and between the protrusion 37E and the columnar portion 39E. In this way, the elastic portion 50A can be deformed in the opposite direction to the direction in which the finger portion 32E falls.

When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32E fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it were pinched. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

6. Modification 5
A gripping device 10F according to a fifth modified example of the above embodiment will be described with reference to Fig. 11. Fig. 11(a) shows a cross-sectional view of the gripping device 10F corresponding to Fig. 4, and Fig. 11(b) shows a cross-sectional view taken along line XB-XB shown in Fig. 11(a).

In the fifth modification, the finger portion 32F has a groove forming portion 36F extending from the base portion 35. The groove forming portion 36F has a U-shaped cross section, and a groove 37F is formed by the groove forming portion 36F. A cavity is formed by the groove 37F.

The elastic portion 50A is placed over the finger portion 32F so as to cover the groove forming portion 36F. Because the groove 37F of the groove forming portion 36F is hollow, the elastic portion 50A can be deformed to enter the groove 37F. In this way, the elastic portion 50A can be deformed in the direction opposite to the direction in which the finger portion 32F falls.

When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32F fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it were pinched. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

7. Modification 6
A gripping device 10G according to a sixth modified example of the above embodiment will be described with reference to Fig. 12 and Fig. 13. Fig. 12 shows a cross-sectional view of the gripping device 10G corresponding to Fig. 4, and Fig. 13 shows a cross-sectional view of the gripping device 10G corresponding to Fig. 2.

In variant 6, multiple through holes 37G are formed in the finger portion 32G, penetrating in the direction in which the finger portion 32G falls, and the through holes 37G form cavities. The elastic portion 50A is placed over the finger portion 32G so as to cover the through holes 37G. Because the through holes 37G are hollow, the elastic portion 50A can deform to enter the through holes 37G. In this way, the elastic portion 50A can deform in the opposite direction to the direction in which the finger portion 32G falls.

As shown in FIG. 13, the gripping device 10G is suitable for gripping a workpiece W having multiple protrusions. When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32G fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it is sandwiched between them. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

In the example shown in FIG. 12, four through holes 37G are formed in the finger portion 32G, but the number of through holes 37G can be changed as appropriate and may be one, two, three, five or more.

8. Modification 7
A gripping device 10H according to a seventh modified example of the above embodiment will be described with reference to Fig. 14. Fig. 14(a) shows a cross-sectional view of the gripping device 10H corresponding to Fig. 4, and Fig. 14(b) shows a cross-sectional view taken along line XIIIB-XIIIB shown in Fig. 14(a).

In the seventh modification, the finger portion 32H has three columnar portions 36H extending from the base portion 35. The columnar portions 36H are spaced apart from one another, and a cavity is formed by the multiple columnar portions 36H. Two columnar portions 36H are located closer to the side where the finger portion 32H falls than the other columnar portions 36H, and the entry of the elastic portion 50A into the cavity between the two columnar portions 36H is not impeded by the other columnar portions 36H.

The elastic portion 50A is placed over the finger portion 32H so as to cover the multiple columnar portions 36H. Because the inside of the columnar portion 36H is hollow, the elastic portion 50A can be deformed to enter between the two columnar portions 36H located on the side where the finger portion 32H falls. In this way, the elastic portion 50A can be deformed in the direction opposite to the direction in which the finger portion 32H falls.

When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the finger parts 32H fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it were pinched. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

9. Modification 8
A gripping device 10I according to an eighth modified example of the above embodiment will be described with reference to Fig. 15. Fig. 15 shows a cross-sectional view of the gripping device 10I corresponding to Fig. 4 .

In the eighth modification, the gripping device 10I includes a pair of protruding members 36I, 37I protruding from the finger portion 32I. The pair of protruding members 36I, 37I are inserted into the finger portion 32I with a gap between them when viewed in the direction in which the finger portion 32I falls, and a cavity is formed between the pair of protruding members 36I, 37I. The pair of protruding members 36I, 37I have higher rigidity than the finger portion 32I. The pair of protruding members 36I, 37I are made of, for example, a metal such as stainless steel, or a hard resin such as plastic.

The elastic portion 50A is placed so as to cover the pair of protruding members 36I, 37I together. In other words, the elastic portion 50A is provided on the finger portion 32I via the pair of protruding members 36I, 37I. Because there is a cavity between the pair of protruding members 36I, 37I, the elastic portion 50A can deform to enter between the pair of protruding members 36I, 37I. In this way, the elastic portion 50A can deform in the opposite direction to the direction in which the finger portion 32I falls.

When the workpiece W is placed between the elastic parts 50A and the palm part 30 is deformed in the thickness direction, the fingers 32I fall toward the palm part 30 and the elastic parts 50A deform while following the shape of the workpiece W, gripping the workpiece W as if it were pinched. Therefore, it is possible to prevent damage to the workpiece W while maintaining the gripping force.

The pair of protruding members 36I, 37I has higher rigidity than the finger portion 32I, so deformation of the pair of protruding members 36I, 37I is small. This improves insertion between multiple workpieces W that are closely spaced. Since deformation of the pair of protruding members 36I, 37I when gripping a workpiece W is small, it contributes to improving the gripping force.

Although the embodiment and modifications 1 to 8 have been described above, the present invention is not limited to the above embodiment and modifications 1 to 8, and can be modified as appropriate within the scope of the spirit of the present invention. The embodiment and modifications 1 to 8 may be combined, or modifications 1 to 8 may be combined with each other. For example, a combination of the gripping device 10H shown in FIG. 14 and the gripping device 10I shown in FIG. 15, a combination of the gripping device 10F shown in FIG. 11 and the gripping device 10G shown in FIG. 12, and a combination of the gripping device 10C shown in FIG. 8 and the gripping device 10D shown in FIG. 9 are possible.

The elastic parts 50A, 50B need only be deformable in the direction opposite to the direction in which the fingers 32A, 32D to 32I fall, and do not necessarily need to be hollow. For example, in the above embodiment, a member (e.g., a sponge) that is more flexible than the finger 32A may be disposed between the pair of protrusions 36A, 37A of the finger 32A.

The elastic parts 50A and 50B may be made of a single material, or may be made of a combination of multiple materials, including rigid members.

10A to 10I Grip device 12 Industrial robot 30 Palm portion 32A, 32D to 32I Finger portion 36I Protruding member 37I Protruding member 38 Annular groove 50A, 50B Elastic portion

Claims (5)

A palm portion and
a plurality of finger portions provided around the palm portion and protruding therefrom, the finger portions being tilted toward the palm portion by deformation of the palm portion in a thickness direction;
an elastic portion having a higher flexibility than the finger portion and provided on the finger portion so as to be deformable in a direction opposite to a direction in which the finger portion falls,
The elastic portion is formed in a bag shape and is placed over the finger portion in an expanded state. An annular groove is formed on the outer circumferential surface of the finger,
The gripping device according to claim 1 , wherein the elastic portion is hooked onto the annular groove. The gripping device according to claim 1 or 2 , wherein the elastic portion includes a first elastic film attached to the finger portion and a second elastic film overlapping the first elastic film. A palm portion and
a plurality of finger portions provided around the palm portion and protruding therefrom, the finger portions being tilted toward the palm portion by deformation of the palm portion in a thickness direction;
an elastic portion provided on the finger portion, the elastic portion having a higher flexibility than the finger portion and being deformable in a direction opposite to a direction in which the finger portion falls;
a protruding member having a higher rigidity than the finger portion and protruding from the finger portion,
A gripping device, wherein the elastic portion is provided on the finger portion via the protruding member. An industrial robot comprising the gripping device according to any one of claims 1 to 4 .

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