Holding device

Abstract

To provide a gripping device that can grip an appropriate amount of objects every time, using a fluid-pressure actuator that bends (curls) while shrinking.SOLUTION: Fluid-pressure actuators 10, which are used in a gripping device 1, include cylindrical tubes that are inflated and shrunk by pressure of fluid, and sleeves which are structures with stretching properties having fiber cords oriented in a predetermined direction twisted therein, and which cover outer peripheral surfaces of the tubes. Spoon-shaped storage parts 50 are provided at tip parts of the fluid-pressure actuators 10. The gripping device is provided with a partition plate 30 that blocks opening surfaces 50a of the storage parts 50 when the fluid-pressure actuators do not bend or when the actuators bend.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a gripping device that uses a fluid pressure actuator that curls when contracted. [Background technology]

[0002] Conventionally, a widely used fluid pressure actuator that uses gas or liquid to expand and contract a tube is a structure having a rubber tube that expands and contracts using air pressure and a sleeve that covers the outer surface of the tube (the so-called McKibben type).

[0003] Such McKibben type fluid pressure actuators are also known to have a structure that curves (curls) when contracted (see Patent Document 1). Specifically, Patent Document 1 discloses a gripping device that uses a plurality of such fluid pressure actuators to grip an object (which may also be called a workpiece). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-088999 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned gripping device using a fluid pressure actuator has the following problems: Specifically, it is difficult to grip an appropriate amount of objects at one time, and the amount of objects that can be gripped may increase or decrease.

[0006] The following disclosure has been made in consideration of the above circumstances, and aims to provide a gripping device that can grip an appropriate amount of an object each time while using a fluid pressure actuator that curves (curls) when contracted. [Means for solving the problem]

[0007] One aspect of the present disclosure is a gripping device (e.g., gripping device 1) that uses a fluid pressure actuator (fluid pressure actuator 10) that bends when contracted, the fluid pressure actuator including a cylindrical tube (tube 110) that expands and contracts due to fluid pressure and a sleeve (sleeve 120) that is an elastic structure in which fiber cords oriented in a predetermined direction are woven and covers the outer peripheral surface of the tube, a spoon-shaped storage portion (storage portion 50) is provided at a tip portion (tip portion 300) of the fluid pressure actuator, and a partition plate (partition plate 30) that closes an opening surface (opening surface 50a) of the storage portion when the fluid pressure actuator is not bent or is curved. Effect of the Invention

[0008] According to the gripping device described above, it is possible to grip an appropriate amount of an object each time while using a fluid pressure actuator that curves (curls) when contracted. [Brief description of the drawings]

[0009] [Figure 1] 1(a), (b) and (c) are perspective views of a gripping device 1 according to this embodiment. [Diagram 2] 2(a) to (d) are side and bottom views of the gripping device 1. FIG. [Diagram 3] FIG. 3 is a side view of the fluid pressure actuator 10. [Figure 4] FIG. 4 is a cross-sectional view of the actuator body 100 taken along the radial direction DR. [Diagram 5] FIG. 5 is an explanatory diagram of the behavior of the fluid pressure actuator 10. As shown in FIG. [Figure 6] 6(a), (b), and (c) are diagrams showing an example of the operation of the gripping device 1. [Figure 7] 7(a), (b) and (c) are perspective views of a gripping device 1A according to a modified example. [Figure 8] 8(a) to (d) are side and bottom views of the gripping device 1A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and the description thereof will be omitted as appropriate.

[0011] (1) Overall configuration of the gripping device 1(a), (b), and (c) are perspective views of the gripping device 1 according to this embodiment. Specifically, Fig. 1(a) is a perspective view of the gripping device 1 when the fluid pressure actuator 10 is not bent. Fig. 1(b) is a perspective view of the gripping device 1 when the fluid pressure actuator 10 is bent. Fig. 1(c) is a perspective view of the gripping device 1 when one of the fluid pressure actuators 10 is bent.

[0012] 2(a) to (d) are side views and bottom views of the gripping device 1. Specifically, Fig. 2(a) and (b) respectively show a side view and bottom view of the gripping device 1 (when the fluid pressure actuator 10 is not bent (contracted)). Fig. 2(c) and (d) respectively show a side view and bottom view of the gripping device 1 (when the fluid pressure actuator 10 is bent (contracted)).

[0013] The gripping device 1 uses a plurality of fluid pressure actuators 10 (flexible, flexible soft actuators) that curve (curl) when contracted. The gripping device 1 can grip an object (which may be called a workpiece) using the plurality of fluid pressure actuators 10. The gripping device 1 may be used as a robot hand, etc.

[0014] The gripping device 1 includes a shovel unit 15, a mounting base 20, and a partition plate 30. The shovel unit 15 includes a fluid pressure actuator 10 and a storage section 50.

[0015] The fluid pressure actuator 10 is attached to a mounting base 20. Specifically, a base end portion 200 (not shown in FIGS. 1 and 2, see FIG. 3) of the fluid pressure actuator 10 is attached to the mounting base 20.

[0016] A spoon-shaped container 50 is provided at the tip 300 (see FIG. 3) of the fluid pressure actuator 10. The container 50 is concave so as to be able to hold an object scooped up by operating (contracting and expanding) the fluid pressure actuator 10. The shovel unit 15 including the container 50 may be called a shovel, a cup, a bucket, or another similar term.

[0017] The partition plate 30 is provided to separate the multiple shovel units 15. Specifically, the partition plate 30 is flat and provided between two shovel units 15. That is, the fluid pressure actuator 10 (shovel units 15) may be provided on both sides of the partition plate 30.

[0018] The partition plate 30 is provided so as to close the opening surface 50a of the accommodation portion 50 when the fluid pressure actuator 10 is not curved (contracted).

[0019] (2) Schematic configuration of fluid pressure actuator 3 is a side view of the fluid pressure actuator 10 according to the present embodiment. R FIG.

[0020] The fluid pressure actuator 10 has an actuator body 100 , a base end 200 and a tip end 300 .

[0021] The actuator body 100 is composed of a tube 110 and a sleeve 120. Fluid flows into the actuator body 100 via a connection port 211a.

[0022] As a basic characteristic, the actuator body 100 is configured such that the actuator body 100 is moved in the axial direction D AX It shrinks in the radial direction D R In addition, the actuator body 100 expands in the axial direction D of the actuator body 100 due to the outflow of fluid from the tube 110.AX It expands in the radial direction D R Such a change in shape of the actuator body 100 causes the fluid pressure actuator 10 to function as an actuator.

[0023] In this embodiment, a McKibben type fluid pressure actuator having such basic characteristics is used, and the axial direction D AX By providing a restraining member 150 (not shown in FIG. 3, see FIGS. 4 and 5, etc.) that restrains (may also be called regulating or limiting, the same applies below) the compression of AX The orthogonal direction, i.e., the radial direction D R It can be curved (curled).

[0024] The fluid used to drive the fluid pressure actuator 10 may be either a gas such as air, or a liquid such as water or mineral oil. In particular, the fluid pressure actuator 10 has high durability capable of withstanding hydraulic driving in which high pressure is applied to the actuator body 100.

[0025] The connection port 211a is connected to a drive pressure source for the fluid pressure actuator 10, specifically, a hose (pipe) connected to a gas or liquid compressor. The fluid that flows in via the connection port 211a passes through a passage hole (not shown) and flows into the inside of the actuator body 100, specifically, into the inside of the tube 110.

[0026] The tube 110 is a cylindrical body that expands and contracts due to the pressure of the fluid. The tube 110 is made of an elastic material such as butyl rubber, since it repeatedly expands and contracts due to the fluid. In addition, when the fluid pressure actuator 10 is hydraulically driven, it is preferable to use at least one material selected from the group consisting of NBR (nitrile rubber), which has high oil resistance, chloroprene rubber, and epichlorohydrin rubber.

[0027] The sleeve 120 is cylindrical and covers the outer circumferential surface of the tube 110. The sleeve 120 is an elastic structure in which fiber cords oriented in a predetermined direction are woven, and diamond shapes are repeated by crossing the oriented cords. By having such a shape, the sleeve 120 undergoes pantograph deformation and follows the contraction and expansion of the tube 110 while regulating it.

[0028] It is preferable to use fiber cords of aromatic polyamide (aramid fiber) or polyethylene terephthalate (PET) as the cords constituting the sleeve 120. However, the cords are not limited to these types of fiber cords, and may be, for example, cords of high-strength fibers such as PBO fiber (polyparaphenylene benzobisoxazole).

[0029] In this embodiment, a restraining member 150 is provided between the tube 110 and the sleeve 120.

[0030] Restraint member 150, axial direction D AX It is not compressed in the radial direction D R (which may be referred to as the deflection direction). That is, the restraint member 150 is deformable only along the axial direction D AX Resistance to compression along the axial direction D AX Orthogonal direction (radial direction D R ) can be transformed into

[0031] In other words, the restraining member 150 is AX It is difficult to deform along the radial direction D R In addition, being deformable may be rephrased as being able to be curved or curled.

[0032] In addition, the restraining member 150 is arranged in a radial direction D at a position on the outer periphery of the tube 110 where the restraining member 150 is provided. R It also has the function of restricting (limiting) the outward expansion of the tube 110 (and the sleeve 120).

[0033] In this embodiment, the restraining member 150 is disposed inside the sleeve 120, specifically, in a space on the radial inner side of the sleeve 120, in the axial direction D AX In this embodiment, the restraining member 150 is formed by using a leaf spring.

[0034] The dimensions of the leaf spring are not particularly limited, and may be selected depending on the size of the fluid pressure actuator 10 and the required force to be generated. The material of the leaf spring is also not particularly limited, but typically may be a material that is easy to bend and resistant to compression, such as a metal such as stainless steel. For example, the restraining member 150 may be formed of a thin plate of carbon fiber reinforced plastic (CFRP). CFRP is less susceptible to plastic deformation than metal, and therefore the fluid pressure actuator 10 is more likely to return to its original straight state after bending.

[0035] The base end 200 is located on the mounting base 20 side. The above-mentioned connection port 211a is formed in the base end 200. AX The device may be provided with a mechanism for sealing one end of the device.

[0036] The tip portion 300 is located on the side of the accommodation portion 50. The tip portion 300 has a groove 310 in the axial direction D of the actuator body 100. AX A mechanism for sealing the other end of the connector may be provided.

[0037] The sealing mechanism of the actuator main body 100 provided at the base end 200 and the tip end 300 may be similar to that of the fluid pressure actuator disclosed in JP 2021-088999 A, for example.

[0038] (3) Behavior of the Fluid Pressure Actuator 10 Fig. 5 is an explanatory diagram of the behavior of the fluid pressure actuator 10. The fluid pressure actuator 10 shown in Fig. 5 is in a state in which the base end 200 side is fixed and the tip end 300 side is freely movable. In other words, the base end 200 side is the fixed end and the tip end 300 side is the free end.

[0039] As described above, when the fluid flows into the fluid pressure actuator 10, the fluid flows in the axial direction D AX However, since the restraining member 150 is provided, the AX Contraction along is constrained (regulated).

[0040] In other words, the restraining member 150 formed of a hard member such as a leaf spring plays a role like a backbone, and the restraining member 150 is arranged in the radial direction D on the opposite side (the lower side in FIG. 5 ) to the position on the outer periphery of the tube 110 and the sleeve 120 where the restraining member 150 is provided. R By expanding outward, the axial direction D AX The dimension of the fluid pressure actuator 10 at the position becomes shorter, and the fluid pressure actuator 10 (specifically, the actuator body 100) bends along direction D1. Note that direction D1 may be called the bending direction. Also, to make it easier to recognize that the fluid pressure actuator 10 bends in direction D1, a mark M (see FIG. 3) may be provided to indicate the position where the restraining member 150 is provided.

[0041] The restraining member 150 is provided between the rubber tube 110 and the sleeve 120 and is arranged in the axial direction D AX Resistance to compression in the perpendicular direction (radial direction D R ) and is disposed at a portion of the actuator body 100 in the circumferential direction.

[0042] In other words, the actuator body 100 (McKibben) moves in the axial direction D AX 1, the portion where the restraining member 150 is arranged cannot contract because the portion of the restraining member 150 has high compressive rigidity. On the other hand, the other portions of the actuator body 100 try to contract along the perpendicular direction (the radial direction D R ) is generated, causing the restraint member 150 to bend with the restraint member 150 as its back surface.

[0043] (4) Operation of the gripping device 1 6(a), (b), and (c) show an example of the operation of the gripping device 1. Specifically, Fig. 6(a), (b), and (c) show an example of the operation of the gripping device 1 scooping up a granular object W. As shown in Fig. 6(a), (b), and (c), the gripping device 1 functions as a robot hand and may be movably supported by a support part.

[0044] As shown in Fig. 6(a), by contracting and curving the fluid pressure actuator 10, a space is formed between the partition plate 30 and the storage section 50 (specifically, the opening surface 50a). With the shovel unit 15 in the open state in this manner, the gripping device 1 is moved to a desired position so as to scoop up the target object W. The gripping device 1 may be moved manually or mechanically.

[0045] As shown in FIG. 6(b), when the fluid pressure actuator 10 is put into a non-contracted state, the fluid pressure actuator 10 returns from a curved state to a straight state, the space between the partition plate 30 and the storage section 50 (opening surface 50a) disappears, and the object W is held within the storage section 50.

[0046] As shown in FIG. 6(c), the gripping device 1 is further moved to another desired position and the fluid pressure actuator 10 is contracted and bent again, whereby a space is formed between the partition plate 30 and the storage section 50, and the object W held in the storage section 50 falls.

[0047] The object W is not particularly limited, but the gripping device 1 can be suitably used for, for example, plating various ingredients contained in a lunch box or the like.

[0048] (5) Example of changes Next, a modified example of the gripping device 1 will be described. Figures 7(a), (b), and (c) are perspective views of a gripping device 1A according to the modified example. Specifically, Figure 7(a) is a perspective view of the gripping device 1A when the fluid pressure actuators 10 are not contracted. Figure 7(b) is a perspective view of the gripping device 1A when the fluid pressure actuators 10 are contracted. Figure 7(c) is a perspective view of the gripping device 1A when some of the fluid pressure actuators 10 are contracted.

[0049] Fig. 8(a)-(d) are side and bottom views of the gripping device 1A. Specifically, Fig. 2(a) and (b) respectively show a side and bottom view of the gripping device 1A (when the fluid pressure actuator 10 is not contracted). Fig. 2(c) and (d) respectively show a side and bottom view of the gripping device 1A (when the fluid pressure actuator 10 is contracted).

[0050] In the gripping device 1A, the partition plate 30A has a cross shape when viewed from the bottom of the gripping device 1A. Four shovel units 15 each composed of a fluid pressure actuator 10 and a storage section 50 are provided.

[0051] The fluid pressure actuators 10 (shovel units 15) are provided in four spaces separated by the partition plate 30A. The partition plate does not have to be cross-shaped, and may form a plurality of spaces (e.g., three or five), and the fluid pressure actuators 10 may be provided in each of the spaces separated by the partition plate.

[0052] Each of the fluid pressure actuators 10 can operate (contract and expand) independently. Therefore, the gripping device 1A can handle a greater number of predetermined unit amounts of objects W in one operation cycle (from scooping up the objects W to releasing them) compared to the gripping device 1. Specifically, the gripping device 1 is provided with two shovel units 15 and can handle two unit amounts of objects W, whereas the gripping device 1A is provided with four shovel units 15 and can handle four unit amounts of objects W.

[0053] (6) Actions and Effects According to the above-described embodiment, the following advantageous effects can be obtained. For example, according to the gripping device 1, the tip portion 300 of the fluid pressure actuator 10 is provided with a spoon-shaped housing portion 50, and a partition plate 30 is provided to close the opening surface 50a of the housing portion 50 when the fluid pressure actuator 10 is not curved (contracted).

[0054] Therefore, the scooped objects W do not spill out, and a roughly constant amount of objects W is held in the storage section 50. In other words, the shovel unit 15 can more reliably grip (hold) an appropriate amount of objects W at one time.

[0055] That is, the gripping device 1 (and gripping device 1A) can grip an appropriate amount of object every time using a fluid pressure actuator that curves (curls) when contracted.

[0056] In addition, the fluid pressure actuator 10 (shovel unit 15) may be provided on both sides of the partition plate 30. This makes it possible to handle a greater number of objects W of a given unit amount in one operation cycle (from scooping up the objects W to releasing them).

[0057] Furthermore, in the gripping device 1A, the partition plate 30A is cross-shaped when viewed from the bottom of the gripping device 1A, and four shovel units 15 are provided. Therefore, a larger number of objects W of a given unit amount can be handled in one operation cycle (from scooping up the objects W to releasing them).

[0058] (7) Other embodiments Although the embodiment has been described above, it will be apparent to those skilled in the art that the present invention is not limited to the description of the embodiment and that various modifications and improvements are possible.

[0059] For example, to more accurately determine the amount of object W held by the storage unit 50, an additional partition plate may be provided on the upper surface side within the storage unit 50. Also, in the above-described embodiment, the partition plate 30 is provided so as to close the opening surface 50a of the storage unit 50 when the fluid pressure actuator 10 is not curved (contracted), but the partition plate 30 may be provided so as to close the opening surface 50a of the storage unit 50 when the fluid pressure actuator 10 is curved.

[0060] Although the gripping device 1 and the gripping device 1A are provided with a plurality of shovel units 15, the number of shovel units 15 may be one.

[0061] In the above-described embodiment, the flexibility of the fluid pressure actuator is ensured by using the restraining member 150, but the flexibility of the fluid pressure actuator may be ensured by a different structure. For example, by providing a flexible frame material with a part made of bellows around the periphery of the fluid pressure actuator, when the fluid pressure actuator contracts, the fluid pressure actuator may bend with the bellows part on the inside.

[0062] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]

[0063] 1, 1A gripping device 10 Fluid pressure actuator 15 Shovel Unit 20 Mounting base 30, 30A Partition plate 50 Storage unit 50a opening surface 100 Actuator body 110 Tube 120 Sleeve 150 Restraint member 200 Proximal end 211a Connection port 300 Tip W Object

Claims

1. A gripping device using a fluid pressure actuator that bends when contracted, the fluid pressure actuator is a soft actuator having flexibility, A spoon-shaped housing portion is provided at a tip end of the fluid pressure actuator, A gripping device provided with a partition plate that closes the opening surface of the accommodation portion when the fluid pressure actuator is not bent or is bent.

2. The fluid pressure actuator includes: A cylindrical tube that expands and contracts due to fluid pressure; A stretchable structure in which fiber cords oriented in a predetermined direction are woven, and a sleeve that covers the outer circumferential surface of the tube; The gripping device of claim 1 .

3. The gripping device according to claim 1 or 2, wherein the fluid pressure actuators are provided on both sides of the partition plate.

4. The partition plate forms a plurality of spaces, The gripping device according to claim 1 or 2, wherein the fluid pressure actuator is provided in each of the plurality of spaces partitioned by the partition plate.

5. The gripping device according to claim 2 , wherein the fluid pressure actuator includes a restraining member provided inside the sleeve and extending from one end side to the other end side in the axial direction of the tube.

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