Hand part, object gripping device and sheet for hand part assembly

Abstract

To stably grip even a heavy object, compared to such a conventional structure as to sandwich the object from both sides.SOLUTION: A hand part (51) includes: a sheet-like suspension part (52) capable of suspending a handle part (9a) of an object (9'); a first link part (54) whose one end (54a) is connected to one end (52a) of the suspension part (52); a second link part (56) whose one end (56a) is connected to other end (54b) of the first link part (54), and to which other end (52b) of the suspension part (52) is connected; a third link part (58) whose one end is connected to other end (56b) of the second link part (56), and that regulates movement of the second link part (56), when the handle part (9a) of the object (9') is suspended on the suspension part (52); and a supported part (60) which is connected to the other end of the third link part (58), and is supported on the tip end of an object griping device (1).SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a hand part that contacts an object, an object gripping device in which the hand part is disposed at a tip portion to grip the object, and a hand part assembly sheet for assembling the hand part, and more particularly, to a hand part, an object gripping device, and a hand part assembly sheet capable of suspending an object.

Background Art

[0002] Regarding an object gripping device, also called a robot arm or a manipulator, which moves an article displayed on a product display shelf in a convenience store or a supermarket, grips and moves an object such as a product produced in a factory, or moves a sterilized tool, an article at risk of infection, a biological sample, etc. at a medical site, the technique described in Patent Document 1 below is known.

[0003] Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2021-094642) describes a configuration in which an object gripping device (100) that grips an object with a pair of gripping members (106) moves the respective gripping members (106) in a direction of approaching and separating from each other to sandwich (grip) the object from both sides with the gripping members (106), lift it, and move it.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] (Problems of the Prior Art) In the technique described in Patent Document 1, the object is held in a state of being sandwiched from both sides. Therefore, the object is held by the frictional force between the side surface of the object and the gripping member. Therefore, when the object is heavy, if the frictional force is insufficient, there is a risk that the object may fall, and there is a problem that it is difficult to stably grip and move the object. In order to increase the frictional force, it is necessary to use a material with a large coefficient of friction or to increase the force of sandwiching from both sides with a gripping member corresponding to the normal force. There is a limit to the material with a large coefficient of friction, and if the sandwiching force is increased too much, there are problems such as deformation of the object. In particular, as the situation and field where the object gripping device is used, attention may be required in terms of hygiene in the food, pharmaceutical, medical fields, etc. In such fields, in order to maintain a hygienic environment, the part (hand part) that directly contacts the object may preferably be disposable. Therefore, if the hand part becomes expensive by using a material with a large coefficient of friction, there is a problem that the cost increases when the expensive hand part is discarded. In addition, if food, drugs, and medical devices are sandwiched with a large force, there is also a risk of damage to the food and containers.

[0006] The technical problem of the present invention is to stably grip even a heavy object compared to the conventional configuration of sandwiching the object from both sides.

Means for Solving the Problems

[0007] In order to solve the above technical problem, the hand part of the invention described in claim 1 is a sheet-like hanging part that contacts the handle part of the object and can hang the handle part, a first link part having one end connected to one end of the hanging part, a second link part having one end connected to the other end of the first link part and the other end of the hanging part connected thereto, a third link part that restricts the movement of the second link part when one end is connected to the other end of the second link part and the handle part of the object is hung on the hanging part, a supported part that is connected to the other end of the third link part and supported by the tip of the object gripping device, characterized by comprising

[0008] The invention according to claim 2 is, in the handle part according to claim 1, a first joint part that rotatably connects between the other end of the first link part and one end of the second link part, a second joint part that rotatably connects between the other end of the second link part and one end of the supported part, comprising rotating with the first joint part and the second joint part, the first link part and the second link part facing and approaching each other, and the second link part and the supported part facing and approaching each other with the first link part interposed therebetween in a folded state, and being deformable between the folded state and an unfolded state in which the first link part, the second link part, and the supported part are separated characterized by this.

[0009] The invention according to claim 3 is, in the handle part according to claim 2, the hanging part, the first link part, the second link part, and the supported part being formed by folding a single sheet characterized by this.

[0010] The invention according to claim 4 is, in the handle part according to claim 3, the first joint part and the second joint part having spring properties that act on a force to shift from the folded state to the unfolded state by the elastic restoring force of the sheet characterized by this.

[0011] In order to solve the above technical problem, the object gripping device of the invention according to claim 5 a sheet-like hanging part that contacts the gripping part of the object and can hang the gripping part, a first link part having one end connected to one end of the hanging part, a second link part having one end connected to the other end of the first link part and the other end of the hanging part connected thereto, and a supported part having one end connected to the other end of the second link part, and a handle part having the same It has a socket part that supports the supported part at the tip, and an arm part that moves the hand part in a direction approaching and separating from the object. It is characterized by comprising the above.

[0012] In order to solve the above technical problem, the sheet for assembling a hand part according to the invention of claim 6 is A sheet for assembling a hand part that bends and assembles a hand part that contacts an object, A sheet-like hanging part that contacts the handle part of the object and can hang the handle part, A first link part with one end connected to one end of the hanging part, A second link part with one end connected to the other end of the first link part and the other end of the hanging part connected thereto, A supported part with one end connected to the other end of the second link part and supported at the tip of the object gripping device, It is characterized by comprising the above.

Advantages of the Invention

[0013] According to the inventions described in claims 1, 5, and 6, compared with the conventional configuration that sandwiches an object from both sides, even a heavy object can be stably gripped. According to the invention described in claim 2, compared with the case where it cannot be deformed between the folded state and the unfolded state, the hand part can be made compact in the folded state, space can be saved, and more hand parts can be accommodated in the same space. According to the invention described in claim 3, a hand part can be formed by folding a single sheet, and manufacturing and assembly can be simplified compared with the case of assembling a plurality of parts. According to the invention described in claim 4, it can be automatically shifted from the folded state to the unfolded state due to its spring property.

Brief Description of the Drawings

[0014]

Figure 1

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Figure 15

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Figure 21

Best Mode for Carrying Out the Invention

[0015] Next, with reference to the drawings, specific examples of embodiments of the present invention (hereinafter referred to as examples) will be described, but the present invention is not limited to the following examples. In the following description using the drawings, illustrations other than the members necessary for the description are appropriately omitted for ease of understanding.

Example

[0016] FIG. 1 is an explanatory diagram of an object gripping device according to Embodiment 1 of the present invention. In FIG. 1, a robot arm 1 as an example of the object gripping device according to Embodiment 1 of the present invention has an arm portion 2. The arm portion 2 has a plurality of arm link portions 3 (3a to 3c) extending in a rod shape, arm joint portions 4 (4a to 4d) that rotatably connect the arm link portions 3a to 3c to each other, and a tip portion 6 supported by the tip arm link portion 3c. Each arm joint portion 4 has a built-in motor (not shown), and it is possible to rotate and move the tip-side arm link portion 3 with respect to the base-side arm link portion 3. Note that the drive source for moving the arm link portion 3 is not limited to a motor, and an air cylinder, a solenoid, or the like can also be used. Further, although the case where the arm joint portion 4 can rotate around one axis is illustrated, it is not limited thereto, and a configuration that can rotate around two or more rotation axes or a universal joint or the like can also be adopted. The tip portion 6 has a base portion 7 as an example of a drive portion and a socket portion 8 as an example of a detachable support portion. In Embodiment 1, two socket portions 8 are provided.

[0017] (Description of the hand portion) (Description of the hand portion for curved surfaces) FIG. 2 is a side view of the hand portion for curved surfaces according to Embodiment 1. FIG. 3 is a developed view of the hand portion for curved surfaces according to Embodiment 1 and is an explanatory diagram of a sheet for hand portion assembly. Each socket part 8 supports a first hand part 11 that contacts and grips an object 9. The first hand part 11, which is an example of the hand part for the curved surface in the first embodiment, is arranged in a pair in a symmetric state.

[0018] The first hand part 11 of the first embodiment is formed by bending a single hand part assembly sheet 31 shown in FIG. 3. The hand part assembly sheet 31 is preferably made of a resin material such as paper, plastic, or rubber, but can also be made of a metal material such as aluminum foil or a non-woven fabric. It is also possible to use a composite material in which a metal or cloth is coated (coated) on the surface of paper or resin. The hand part assembly sheet 31 can be processed (cut out) into a desired shape using a laser processing machine or the like. Note that the method of processing into the desired shape is not limited to a configuration using a laser processing machine, and press processing or manual cutting by a person is also possible. In FIG. 3, the cutting part is shown by a solid line, the mountain fold part is shown by a broken line, and the valley fold part is shown by a one-dot chain line.

[0019] In FIG. 2, the first hand part 11 of the first embodiment has a gripping part 12 facing the object 9. In FIGS. 2 and 3, the gripping part 12 is formed in a flat plate shape or a sheet shape extending in the longitudinal direction along the one end part 12a side to the other end part 12b side. Therefore, the gripping part 12 is configured to be able to bend or deflect along the longitudinal direction. In FIG. 2, on the inner side of the gripping part 12, which is the side where the first hand parts 11 face each other, a contact surface 12c that can contact the object 9 is formed.

[0020] In FIGS. 2 and 3, one end part 14a of the first link part 14 is connected to one end part 12a of the gripping part 12. The first link part 14 is in a form bent around the parts of the one end parts 12a and 14a with respect to the gripping part 12, and the first link part 14 and the gripping part 12 can be relatively inclined and rotated. In FIG. 3, in the sheet 31 for hand part assembly of the first embodiment, link reinforcing portions 14e and 14f are provided on both sides in the short direction (width direction) with respect to the link main body portion 14d of the first link portion 14. Restoration assisting portions 14g are formed on the inner end side in the width direction of each of the link reinforcing portions 14e and 14f. The restoration assisting portion 14g is formed in a shape in which the sheet is folded back. The restoration assisting portion 14g of the first embodiment is not adhered to either the link main body portion 14d or the link reinforcing portions 14e and 14f. A plurality of claw portions 14e1 are formed at the outer end portion in the width direction of the first link reinforcing portion 14e. A plurality of openings 14f1 are formed in the second link reinforcing portion 14f corresponding to the claw portions 14e1. The opening 14f1 of the first embodiment is formed in a rectangular shape extending in the width direction. In a state where the first hand portion 11 is assembled, the claw portions 14e1 are fitted into the openings 14f1.

[0021] A plurality of joint portions 16 (16a to 16d) are arranged between the gripping portion 12 and the first link portion 14. The first joint portion 16a to the fourth joint portion 16d are arranged at intervals from the one end portions 12a and 14a toward the other end portions 12b and 14b, and the lengths of the joint portions 16a to 16d are formed to be longer toward the other end portions 12b and 14b side. Therefore, the interval between the gripping portion 12 and the first link portion 14 is formed wider on the other end portions 12b and 14b side than on the one end portions 12a and 14a side. In FIG. 3, in the first hand portion 11 of the first embodiment, in the sheet 31 for hand part assembly, the first joint portion 16a to the third joint portion 16c are formed on the side of the gripping portion 12. After bending the first joint portion 16a to the third joint portion 16c, the end portion on the first link portion 14 side is connected by attaching it to the surface of the first link portion 14 with an adhesive or glue or the like.

[0022] A plurality of folding portions (an example of a deployment assisting portion) 16b2 are formed in the middle of the second joint portion 16b in the length direction (the direction from the gripping portion 12 toward the first link portion 14). The folding portion 16b2 is configured in the same manner as the restoration assisting portion 14g. In the third joint portion 16c, a folding portion 16c2 is provided in the middle in the longitudinal direction, and a second folding portion (an example of a development assisting portion, an example of a gripping force assisting portion) 16c3 is also formed in the central portion 16c1.

[0023] The fourth joint portion 16d is formed on the extension of the other end portion 14b of the first link portion 14 in the hand portion assembly sheet 31 of FIG. 3. After being bent at the other end portion 14b of the first link portion 14, the fourth joint portion 16d connects the first link portion 14 and the gripping portion 12 by inserting a joint portion connecting piece 16d3 into a connecting slit 12b1 at the other end portion 12b of the gripping portion 12. In the fourth joint portion 16 of the first embodiment, a folding portion 16d2 is provided in the same manner as the second joint portion 16b and the third joint portion 16c. In the first embodiment, as the joint portion 16, a configuration in which four joint portions of the first joint portion 16a to the fourth joint portion 16d are provided is exemplified, but it is not limited thereto. It is also possible to have three or less, or five or more.

[0024] A supported portion 18 is connected to the other end portion 12b of the gripping portion 12 via a first joint portion 17. In FIGS. 2 and 3, the supported portion 18 of the first embodiment is configured to have a triple thickness by folding and bonding three supported main body portions 18a in the hand portion assembly sheet 31. Further, the supported portion 18 of the first embodiment has an overhanging portion 18b that protrudes laterally from the side surface of the supported main body portion 18a. Furthermore, the supported portion 18 of the first embodiment has a connecting band portion 18c. The tip end portion 18c1 of the connecting band portion 18c is fixed to the side surface of the supported main body portion 18a opposite to the base end portion 18c2 of the connecting band portion 18c with an adhesive or the like. Then, by inserting a supported connecting piece 14c extending from the other end portion 14b of the first link portion 14 into the gap between the connecting band portion 18c and the supported main body portion 18a, the other end portion 14b of the first link portion 14 is connected to the supported portion 18. In the first embodiment, the length of the supported connecting piece 14c is formed to be long, and is configured to be freely movable in the longitudinal direction with respect to the connecting band portion 18c during folding and unfolding described later.

[0025] FIG. 4 is a schematic explanatory view of the deployment and folding of the hand part of Example 1. FIG. 4A is an explanatory view of the deployed state, and FIG. 4B is an explanatory view of the folded state. In FIG. 4, in the first hand part 11 of Example 1, it is bent at one end parts 12a and 14a which are the connecting parts between the gripping part 12 and the first link part 14, and is bent at the base end part of the supported connecting piece 14c which is the connecting part between the first link part 14 and the supported part 18. It is bent at one end parts of the joint parts 16a to 16d which are the connecting parts between the respective joint parts 16a to 16d and the gripping part 12, and at the other end parts of the joint parts 16a to 16d which are the connecting parts between the respective joint parts 16a to 16d and the first link part 14. Furthermore, by bending at the central parts 16a1 to 16d1 of the respective joint parts 16a to 16d, it can be deformed from the deployed state shown in FIG. 4A to the folded state shown in FIG. 4B. In the state where the first hand part 11 is folded, as shown in FIG. 4B, the first link part 14 and the gripping part 12 face and are close to each other, and the supported part 18 and the gripping part 12 face and are close to each other with the first link part 14 interposed therebetween. Therefore, the first hand part 11 can be folded into a substantially flat plate shape, and the folded state can be maintained by pressing the gripping part 12 and the supported part 18 (the overhanging part 18b thereof) with an external force such as a finger or a member, an external member.

[0026] FIG. 5 is an explanatory view of the positional relationship between the claw part and the opening part of Example 1. FIG. 5A is an explanatory view in the deployed state, and FIG. 5B is an explanatory view in the folded state. When the external force is released from the state where the first hand part 11 is folded, the first hand part 11 shifts from the folded state shown in FIG. 4B to the deployed state shown in FIG. 4A by the elastic restoring force (spring property) of the joint parts 16a to 16d where the hand part assembly sheet 31 is bent. In the first hand portion 11 of the first embodiment, in the unfolded state shown in FIGS. 4A and 5A, the link reinforcing portions 14e and 14f are open with respect to the link main body portion 14d, and as a whole, the first link portion 14 has a triangular cross section as shown in FIG. 5A. On the other hand, in the folded state shown in FIGS. 4B and 5B, the link reinforcing portions 14e and 14f are closed and are folded in a state of facing and approaching the link main body portion 14d. In a configuration where the link reinforcing portions 14e and 14f are not provided, the first link portion 14 is composed of only one sheet (that is, only the link main body portion 14d), and has weak rigidity. When the object 9 contacts the contact surface 12c and a force is applied to the first hand portion 11, it may bend and be difficult to grip. In contrast, in a configuration where the link reinforcing portions 14e and 14f are provided, the cross section is triangular, and the overall rigidity is improved compared to a configuration of only one sheet, making it easier to grip the object 9.

[0027] When the first hand portion 11 changes from the folded state to the unfolded state, the restoring force of the hand portion assembly sheet 31 is used for the unfolding of the link reinforcing portions 14e and 14f. When using the restoring force of the hand portion assembly sheet 31, depending on the material, it may not return to the angle required for unfolding when folded along the fold line. However, in the first embodiment, the restoring auxiliary portion 14g is provided, and the angle required for unfolding is reduced to half of the case where the restoring auxiliary portion 14g is not provided. As an example, when it is desired to deploy the link reinforcing portions 14e and 14f by 60° with respect to the link main body portion 14d, in a configuration without the restoring auxiliary portion 14g, it is necessary to deploy 60° with the restoring force of the sheet. However, if the restoring auxiliary portion 14g is provided, the restoring auxiliary portion 14g can be deployed by 30° with respect to the link main body portion 14d, and the link reinforcing portions 14e and 14f can be deployed by 30° with respect to the restoring auxiliary portion 14g. Therefore, by providing the restoring auxiliary portion 14g, even when using a sheet material with a weak restoring force, it is possible to easily deploy to the target posture (target state, target deployment angle) using the restoring force of the sheet material. In the first embodiment, the configuration of providing one (one stage) of the restoring auxiliary portion 14g is exemplified, but it is also possible to adopt a configuration of providing multiple stages according to the restoring force of the sheet material and the target deployment angle.

[0028] Also, in the first hand part 11 of the first embodiment, the folded-back parts 16b2 to 16d2 are provided at the joint parts 16b to 16d. Therefore, similar to the restoration assisting part 14g, the elastic restoration of the joint parts 16b to 16d facilitates the transition from the folded state to the unfolded state, and even when the object 9 contacts the gripping part 12 and the joint parts 16a to 16d receive a force in the direction of bending, the reaction force and the restoring force act, making it easier to apply a force for gripping the object 9. In particular, in the first embodiment, by providing the second folded-back part 16c3, the unfolding of the third joint part 16c is promoted until the state shown in FIG. 4A, and the first hand part 11 can surely and easily transition to the unfolded state without remaining in an insufficient unfolded state.

[0029] FIG. 6 is an explanatory diagram of the operation of the hand part shown in FIGS. 2 to 5. FIG. 6A is an explanatory diagram of the comparative example, and FIG. 6B is an explanatory diagram of the first embodiment. In the first hand part 11 shown in FIGS. 2 to 5, the gripping part 12 is supported by a plurality of joint parts 16a to 16d having elastic force from the inside. Therefore, when the gripping part 12 contacts the surface of the object 9, in the configuration without joint parts, as shown in FIG. 6A, the gripping part is pushed as a whole, whereas in the first embodiment, as shown in FIG. 6B, the portion 41 between the one end part 12a of the gripping part 12 and the first joint part 16a, the portion 42 between the first joint part 16a and the second joint part 16b, the portion 43 between the second joint part 16b and the third joint part 16c, the portion 44 between the third joint part 16c and the fourth joint part 16d, and the portion 45 between the fourth joint part 16d and the other end part 12b of the gripping part 12 are each likely to have a shape along the outer surface of the object 9. Therefore, even for an object 9 having a curved outer surface, the contact area becomes wide, and it becomes easy to grip stably.

[0030] (Explanation of the hanging hand part) FIG. 7 is an explanatory diagram of the hanging hand part of the first embodiment. FIG. 7A is a schematic diagram, and FIG. 7B is a perspective view. FIG. 8 is a development view of the hanging hand part of the first embodiment and is an explanatory diagram of the hand part assembly sheet. Each socket part 8 can support and mount a second hand part 51 that can be used for a purpose different from that of the first hand part 11. The second hand part 51, which is an example of the hand part for suspension in the first embodiment, has a gripping part 52 that contacts the handle part 9a of the object 9'. In FIGS. 7 and 8, the gripping part 52 is formed in a flat plate shape or a sheet shape extending from one end part 52a side to the other end part 52b side. Therefore, the gripping part 52 is configured to be capable of bending or deflecting. In FIG. 7, a contact surface 52c capable of contacting the object 9' is formed on the surface of the gripping part 52. In FIG. 8, a second connecting piece 52d is formed on the other end part 52b side of the gripping part 52. Further, on the other end side of the second connecting piece 52d, a fixing part 52e is formed, and peeling prevention parts 52f folded and attached to the fixing part 52e are provided at both end parts in the width direction of the fixing part 52e.

[0031] In FIGS. 7 and 8, one end part 54a of the first link part 54 is connected to one end part 52a of the gripping part 52. The first link part 54 is in a form bent around the parts of the one end parts 52a and 54a with respect to the gripping part 52, and the first link part 54 and the gripping part 52 can be inclined and rotated relative to each other. In FIG. 8, in the hand part assembly sheet 81 for suspension in the first embodiment, the first link part 54 has a first link main body part 54d, first link reinforcing parts 54e and 54f, a first restoring auxiliary part 54g, a first claw part 54e1, and a first opening part 54f1 configured in the same manner as the link main body part 14d, link reinforcing parts 14e and 14f, restoring auxiliary part 14g, claw part 14e1, and opening part 14f1 described above.

[0032] In FIGS. 7 and 8, the other end part 54b of the first link part 54 is rotatably connected to a second link part 56 via a first joint part 55. The first joint part 55 is configured in the same manner as the first restoring auxiliary part 54g, and the restoring force of the hand part assembly sheet 81 acts on the first link part 54 in a direction to open it with respect to the second link part 56. As a result, a force (tension) for pulling the gripping part 52 in the longitudinal direction acts. The second link portion 56 has a second link main body portion 56d, second link reinforcing portions 56e, 56f, a second restoration assisting portion 56g, a second claw portion 56e1, and a second opening portion 56f1, similar to the link main body portion 14d, link reinforcing portions 14e, 14f, restoration assisting portion 14g, claw portion 14e1, and opening portion 14f1.

[0033] In FIG. 8, on the other end portion 56b side of the second link main body portion 56d, a reinforcing portion 56h is formed. The reinforcing portion 56h is attached to the second link main body portion 56d in a folded-back state with an adhesive or the like. Therefore, the portion of the reinforcing portion 56h is reinforced with the sheet being double (the thickness of the sheet being twice). Also, a second connecting slit 56i is formed in the second link main body portion 56d at substantially the center in the longitudinal direction. By inserting the second connecting piece 52d of the gripping portion 52 into the second connecting slit 56i, the gripping portion 52 and the second link portion 56 are connected in a rotatable state. Further, the fixing portion 52e of the gripping portion 52 is fixed to the second link main body portion 56d with an adhesive or the like.

[0034] On the other end portion 56b side of one of the second link reinforcing portions 56e, a first bending reinforcing portion 56j is formed. The first bending reinforcing portion 56j is folded back and attached to the outer surface side of the second link reinforcing portion 56e. On the outer end portion in the width direction of the other second link reinforcing portion 56f, a second bending reinforcing portion 56m is formed. The second bending reinforcing portion 56m is folded back and attached to the second link reinforcing portion 56f. In the reinforcing portion 56h, a third bending reinforcing portion 56k is formed on the other end portion 56b side in the longitudinal direction and on the second bending reinforcing portion 56m side in the width direction. The third bending reinforcing portion 56k is folded back and attached to the outer surface side of the reinforcing portion 56h. Also, in the reinforcing portion 56h, second peeling prevention portions 56n are formed on the other end side in the longitudinal direction than the third bending reinforcing portion 56k and on both sides in the width direction.

[0035] On the other end side of the reinforcing portion 56h of the second link portion 56, a third link portion 58 is connected via a second joint portion 57. The third link portion 58 is formed with a third link main body portion 58d, third link reinforcing portions 58e and 58f, a third restoring auxiliary portion 58g, a third claw portion 58e1, and a third opening portion 58f1, similar to the link main body portion 14d, link reinforcing portions 14e and 14f, restoring auxiliary portion 14g, claw portion 14e1, and opening portion 14f1. Further, the third link portion 58 is formed with deflection reinforcing portions 58j, 58k, and 58m for the same purpose as the respective deflection reinforcing portions 56j, 56k, and 56m of the second link portion 56.

[0036] The second joint portion 57 is configured in the same manner as the first restoring auxiliary portion 54g and the first joint portion 55, and applies a force in the opening direction to the second link portion 56 with respect to the third link portion 58 by the restoring force of the hand unit assembly sheet 81. In the first embodiment, due to this force, the portions of the third link reinforcing portions 58e and 58f and the third deflection reinforcing portion 58k of the third link portion 58 come into contact with the portion where the second link main body portion 56d, the reinforcing portion 56h, and the third deflection reinforcing portion 56k overlap. As a result, the second link portion 56 is designed not to open more than 90 degrees with respect to the third link portion 58. And even when a heavy load of the object 9' is applied to the gripping portion 52 and a force in the opening direction of the second link portion 56 with respect to the third link portion 58 acts, the overlapping portion of the reinforcing portion 56h etc. and the third link reinforcing portions 58e and 58f, and the third deflection reinforcing portion 58k are in contact and abutment, making it easier to receive the load. Therefore, when a load acts, the movement of the second link portion 56 with respect to the third link portion 58 is restricted. Also, when a load acts, the second link reinforcing portions 56e and 56f are likely to bend, but in the first embodiment, the deflection of the second link reinforcing portions 56e and 56f is suppressed by being reinforced by the first deflection reinforcing portion 56j and the second deflection reinforcing portion 56m.

[0037] The peeling prevention portion 52f is attached to the side surface of the second link portion 56 (the portion where the second connection slit 56i overlaps the fixing portion 52e) in order to prevent the fixing portion 52e from peeling off from the second link main body portion 56d. Similarly, the second peeling prevention part 56n is attached so as to straddle from the side surface of the second link main body part 56d to the outer surfaces of the second link reinforcing parts 56e and 56f in order to prevent the reinforcing part 56h from peeling off from the second link main body part 56d.

[0038] Note that the reinforcing part 56h of the second link part 56 has the function of reinforcement as described above, but also has the function of shifting the connection location between the second link part 56 and the third link part 58 not to the end of the second link part 56 but to the inside of the second link part 56. By shifting the connection location between the second link part 56 and the third link part 58 to the inside of the second link part 56, when an object is suspended, the third link reinforcing parts 58e and 58f will be pressed against the second link part 56, restricting the angle between the second link part 56 and the third link part 58 to 90 degrees or less, and enabling it to be used as a hook shape (the shape of a hanging hook claw).

[0039] On the other end 58b side of the third link part 58, a supported part 60 is connected via a third joint part 59. The third joint part 59 has a third connecting piece 59a formed on the outer side in the width direction. The supported part 60 is configured to be three - layer thick by being bonded together, similar to the supported part 18. Also, in the supported part 60 of the second hand part 51 of the first embodiment, a third connecting slit 60a into which the third connecting piece 59a is inserted is formed. After the third connecting piece 59a is inserted into the third connecting slit 60a, it is bent inward, and the third joint part 59 and the supported part 60 are attached with an adhesive. If the third joint part 59 and the supported part 60 are simply fixed with only an adhesive, there is a risk of peeling when an object is suspended and a load is applied. In contrast, in the first embodiment, by inserting the third connecting piece 59a into the third connecting slit 60a, it is in a form where it is hooked by the third connecting piece 59a, making it difficult for the third joint part 59 and the supported part 60 to peel off.

[0040] In addition, in the first embodiment, the third joint portion 59 is provided to shift the connection position between the third link portion 58 and the supported portion 60 inward, similar to the aforementioned reinforcing portion 56h. That is, when the end of the supported portion 60 is the connection position with the third link portion 58, the supported portion 60 may fall off from the socket portion 8 when an object is suspended. Therefore, it is desirable that the connection position between the third link portion 58 and the supported portion 60 be shifted from the end of the supported portion 60.

[0041] FIG. 9 is a schematic explanatory view of the deployment and folding of the hand portion of the first embodiment. FIG. 9A is an explanatory view of the deployed state, and FIG. 9B is an explanatory view of the folded state. In FIG. 9, in the second hand portion 51 of the first embodiment, it is bent at one end portions 52a and 54a which are the connecting portions between the gripping portion 52 and the first link portion 54, bent at the first joint portion 55 which is the connecting portion between the first link portion 54 and the second link portion 56, bent at the second joint portion 57 which is the connecting portion between the second link portion 56 and the third link portion 58, bent at the third joint portion 59 which is the connecting portion between the third link portion 58 and the supported portion 60, and also bent at the central portion of the gripping portion 52, so that it can be deformed from the deployed state shown in FIG. 9A to the folded state shown in FIG. 9B. When the second hand portion 51 is in the folded state, as shown in FIG. 9B, the first link portion 54 and the second link portion 56 face and are close to each other with the gripping portion 52 interposed therebetween, the second link portion 56 and the third link portion 58 face and are close to each other with the first link portion 54 interposed therebetween, and the supported portion 60 is folded in a state of facing and being close to the second link portion 56 with the third link portion 58 and the first link portion 54 interposed therebetween. Also, similar to the first hand portion 11, the second hand portion 51 can shift from the folded state to the deployed state by the elastic restoring force (spring property) of the hand portion assembly sheet 81 at the joint portions 55 and 57.

[0042] In the second hand part 51 shown in FIGS. 7 to 9, the gripping part 52 can contact the handle part 9a of the object 9' and suspend and hold the object 9'. Also, in the second hand part 51 of the first embodiment, it is configured to naturally shift to the deployed state with springiness. That is, a force in the direction in which the sheet-like gripping part 52 expands is applied, and a force to withstand the load of the gripping part 52 is applied. Therefore, even a heavy object 9' can be stably gripped and suspended by the second hand part 51.

[0043] (Description of the tip) (Description of the base part) FIG. 10 is an explanatory diagram of an example of the base part of the first embodiment. FIG. 10A is an explanatory diagram of a state in which the socket part is attached, FIG. 10B is an explanatory diagram of a state in which the hand part is opened, and FIG. 10C is an explanatory diagram of a state in which the hand part is removed. In FIG. 10, the base part 7 of the first embodiment has a base base 101 supported by the arm link part 3c. A motor 102 as an example of a drive source is supported by the base base 101. A shaft 103 as an example of a shaft part extending toward the tip of the robot arm 1 is supported by the base base 101. A slider 104 as an example of an operating body is supported on the shaft 103 so as to be movable along the axial direction. The slider 104 has a rack 104a that meshes with the output gear of the motor 102, and can reciprocate between the hand release position shown in FIG. 10B and the hand removal position shown in FIG. 10C along the axial direction by the forward and reverse rotation of the motor 102. Also, a pair of transmission protrusions 104b (only one on the front side is shown in FIG. 10) as an example of a transmission part connected to the transmitted part of the socket part 8 are arranged on the slider 104.

[0044] FIG. 11 is an explanatory diagram of the locking part for attachment and detachment. Further, a pair of socket support portions 106 facing each other with the shaft 103 interposed therebetween are formed on the base base portion 101. The socket portion 8 is detachably supported on each socket support portion 106. A positioning protrusion 107 is supported on each socket support portion 106. Further, a lock hole 108 is formed in the flange portion 101a near the positioning protrusion 107 on the base base portion 101. In Example 1, the number of the positioning protrusions 107 and the lock holes 108 is a configuration of two sets of two each, but the number can be one or three or more.

[0045] FIG. 12 is an explanatory view of another example of the base portion. FIG. 12A is an explanatory view of a state where the socket portion is mounted. FIG. 12B is an explanatory view of a state where the hand portion is opened. FIG. 12C is an explanatory view of a state where the hand portion is removed. FIG. 13 is an explanatory view of another example of the base portion. FIG. 13A is an explanatory view of a state where the socket portion is mounted. FIG. 13B is an explanatory view of a state where the hand portion is opened. FIG. 13C is an explanatory view of a state where the hand portion is removed. Instead of the base portion 7 capable of mounting two socket portions 8 as shown in FIG. 10, as shown in FIGS. 12 and 13, the base portions 7′ and 7″ capable of mounting three socket portions 8 may be used.

[0046] In the base portion 7′ shown in FIG. 12, three socket portions 8 can be mounted symmetrically with respect to the point centered on the shaft 103. Therefore, three transmission protrusions 104b are provided on the slider 104′ (only two are shown in FIG. 12), and the socket support portion 106′ is also formed in a triangular shape. In the base portion 7″ shown in FIG. 13, one socket portion 8 can be mounted on the right side in FIG. 13, and two socket portions 8 can be mounted on the left side in FIG. 13. Therefore, one transmission protrusion 104b is provided on the right side and two transmission protrusions 104b are provided on the left side on the slider 104″ as well. One set of positioning protrusions 107 and lock holes 108 are arranged on the right side and two sets of positioning protrusions 107 and lock holes 108 are arranged on the left side on the socket support portion 106″.

[0047] (Description of Socket Portion) FIG. 14 is an explanatory view of the socket portion of Example 1. FIG. 14A is a perspective view, FIG. 14B is a view seen from the direction of arrow XIVB in FIG. 14A, FIG. 14C is a view seen from the direction of arrow XIVC in FIG. 14A, FIG. 14D is a view seen from the direction of arrow XIVD in FIG. 14A, FIG. 14E is a view seen from the direction of arrow XIVE in FIG. 14A, and FIG. 14F is a view seen from the direction of arrow XIVF in FIG. 14A. FIG. 15 is an explanatory view of the housing portion of the socket portion of Example 1. FIG. 15A is a perspective view, FIG. 15B is a view seen from the direction of arrow XVB in FIG. 15A, FIG. 15C is a view seen from the direction of arrow XVC in FIG. 15A, FIG. 15D is a view seen from the direction of arrow XVD in FIG. 15A, FIG. 15E is a view seen from the direction of arrow XVE in FIG. 15A, and FIG. 15F is a view seen from the direction of arrow XVF in FIG. 15A. FIG. 16 is an explanatory view of the operation of the socket portion of Example 1. FIG. 16A is an explanatory view of the state where the hand portion is open, FIG. 16B is an explanatory view of the state where the hand portion is closed, and FIG. 16C is an explanatory view of the state where the hand portion is removed.

[0048] In FIGS. 14 to 16, the socket portion 8 of Example 1 has a housing portion 111. The housing portion 111 of Example 1 has a pair of left and right side wall portions 112 and a connecting wall portion 113 that connects the ends of the side wall portions 112. In FIGS. 14F and 15F, a pair of positioning holes 113a into which the positioning protrusions 107 are fitted are formed in the connecting wall portion 113. Further, a lock member 115 that fits into the lock hole 108 is supported by the connecting wall portion 113. The lock member 115 has a push portion 115a that is pushed and operated by a person's finger, a lock protrusion 115b that can be inserted into and retracted from the lock hole 108, and a spring 115c that biases the lock member 115 in the direction in which the lock protrusion 115b is inserted into the lock hole 108. In FIGS. 14 to 16, a slide rack 114 is movably supported inside each side wall portion 112. Rack teeth are formed on the upper surface of the slide rack 114. One slide rack 114 is connected by a connecting bar 116. A transmitted hole 116a into which the transmission protrusion 104b is fitted is formed in the connecting bar 116.

[0049] FIG. 17 is an explanatory view of the gear to be transmitted in Example 1, FIG. 17A is a perspective view, and FIG. 17B is an exploded view. A combined gear 117 is engaged with the rack teeth of the slide rack 114. In FIG. 17, the combined gear 117 of Example 1 includes a first notched gear 117a, a second notched gear 117b coaxial with the first notched gear 117a, and a sector cam 117c coaxial with the second notched gear 117b. The second notched gear 117b is engaged with the rack teeth of the slide rack 114. The second notched gear 117b is formed with a wider range of gear teeth than the first notched gear 117a, and the first notched gear 117a is formed with gear teeth in a range corresponding to the range for opening and closing the first handle portion 11. The parts 114 to 117 to be transmitted in Example 1 are constituted by the slide rack 114, the connecting bar 116, and the combined gear 117.

[0050] In FIGS. 14 to 16, a first gear 118 as an example of a first transmission part is rotatably supported on the side of the combined gear 117. The first gear 118 has a first engaging portion 118a that meshes with the first notched gear 117a, and a first idle portion 118b that is provided adjacent to the first engaging portion 118a and does not mesh with the first notched gear 117a and with which drive is not transmitted. The first engaging portion 118a is formed in a range corresponding to the first notched gear 117a. Therefore, in a state where the combined gear 117 rotates and the first gear 118 stops, the sector cam 117c continues to contact the first idle portion 118b while sliding, so as not to rotate the first gear 118.

[0051] Also, a second gear 119 as an example of a second transmission part is rotatably supported coaxially and inside the first gear 118. The second gear 119 has a second engaging portion 119a that meshes with the second notched gear 117b. The second engaging portion 119a is formed in a range corresponding to the second notched gear 117b. Therefore, with respect to the rotation phases of the combined gear 117, the first gear 118, and the second gear 119, the second engaging portion 119a is arranged at a position corresponding to the first idle portion 118b.

[0052] FIG. 18 is an explanatory view of an end face cam, FIG. 18A is a side view, FIG. 18B is a cross-sectional view taken along line XVIIIB-XVIIIB of FIG. 18A, and FIG. 18C is a cross-sectional view taken along line XVIIIC-XVIIIC of FIG. 18A. Inside the second gear 119, an end face cam 121, which is an example of an operating member for manual attachment and detachment, is rotatably supported. The end face cam 121 can rotate integrally with the second gear 119 about a rotation center 121a. In FIGS. 15 and 18, on the inner surface side of the pair of left and right end face cams 121, a first guide rib 131, which is an example of a first guiding portion, is formed radially outside about the rotation center 121a. The first guide rib 131 is formed in an arc shape, and a recess 131a is formed in the middle portion in the circumferential direction of the arc. On both sides in the circumferential direction with respect to the recess 131a, inclined surfaces 131b and 131c are formed. On the inner surface side of the end face cam 121, a second guide rib 132, which is an example of a second guiding portion, is formed radially inside the first guide rib 131. The second guide rib 132 is formed in an arc shape, and a recess 132a is formed at the outer end portion in the circumferential direction of the arc. An inclined surface 132b is formed on the inner side in the circumferential direction with respect to the recess 132a.

[0053] In FIG. 14, inside the end face cam 121, a socket rotating portion 122, which is an example of a supporting portion, is supported. The socket rotating portion 122 is configured to be rotatable about a rotation shaft 122a integrally with the first gear 118. The socket rotating portion 122 is formed in a box shape having a hand portion accommodation space 123 inside. In the hand portion accommodation space 123, a push-out plate 124 is disposed, and the push-out plate 124 is pushed outward by a spring 126, which is an example of a biasing member. A plurality of hand portions 11 and 51 can be accommodated in the hand portion accommodation space 123. The outermost hand portions 11 and 51 are in a deployed state, and the inner hand portions 11 and 51 are held in a folded state.

[0054] FIG. 19 is an explanatory view of a state in which the end face cam has moved to the removal position. FIG. 19A is a sectional view of the main part, FIG. 19B is an explanatory view of the part of the first guide rib, and FIG. 19C is an explanatory view of the part of the second guide rib. FIG. 20 is an explanatory view of a state in which the end face cam has moved to the extrusion position. FIG. 20A is a sectional view of the main part, FIG. 20B is an explanatory view of the part of the first guide rib, and FIG. 20C is an explanatory view of the part of the second guide rib. FIG. 21 is an explanatory view of a state in which the end face cam has moved to the use position. FIG. 21A is a sectional view of the main part, FIG. 21B is an explanatory view of the part of the first guide rib, and FIG. 21C is an explanatory view of the part of the second guide rib.

[0055] In FIGS. 14 and 19 to 21, a pair of first hand pressing parts 136 are supported at positions corresponding to the first guide rib 131 on the socket rotating part 122. The first hand pressing part 136 is supported by the socket rotating part 122 at the part of the first base end part 136a, and a first holding part 136c having a bent shape inside the socket rotating part 122 is formed at the first tip part 136b. A first guided projection 136d protruding outward is formed on the outer surface of the first tip part 136b. Note that the first hand pressing part 136 is composed of a leaf spring such that the first tip part 136b is biased outward. Therefore, the first guided projection 136d is configured to contact the inner surface of the first guide rib 131, and when the first guide rib 131 moves as the end face cam 121 rotates, the first guided projection 136d moves along the unevenness of the first guide rib 131.

[0056] In FIGS. 14 and 19 to 21, a pair of second hand pressing portions 137 are supported at positions corresponding to the second guide rib 132 on the socket rotating portion 122. The second hand pressing portion 137 is configured in the same manner as the first hand pressing portion 136, and has a second base end portion 137a, a second tip end portion 137b, a second holding portion 137c, and a second guided projection 137d. The second holding portion 137c of the second hand pressing portion 137 is disposed at a position outside the internal space of the socket rotating portion 122 with respect to the first holding portion 136c. Specifically, it is disposed at a position outside by a length considering the thickness of the supported portions 18, 60 of the hand portions 11, 51 with respect to the first holding portion 136c.

[0057] In FIG. 19, when the end face cam 121 moves to the removal position shown in FIG. 19, the second guided projection 137d reaches the position of the recess 132a of the second guide rib 132, and deforms outward by the elastic force of the leaf spring of the second hand pressing portion 137, and the second guided projection 137d contacts the recess 132a. The deformation of the second hand pressing portion 137 is not limited to the leaf spring, and it is also possible to add a coil spring or the like to cause deformation. Therefore, the second holding portion 137c also moves outward, and the second holding portion 137c no longer holds the supported portions 18, 60 of the hand portions 11, 51. Accordingly, the hand portions 11, 51 are detached from the socket portion 8 and removed. At this time, the first guided projection 136d is in contact with the inner surface 131d of the first guide rib 131. Therefore, the first holding portion 136c is held inward and contacts and holds the supported portions 18, 60 of the hand portions 11, 51 that are accommodated most outwardly within the socket rotating portion 122. With the detachment of the used hand portions 11, 51, the outermost hand portions 11, 51 that were held and folded by the first holding portion 136c are deployed.

[0058] In FIG. 20, when the end face cam 121 rotates from the position shown in FIG. 19 and moves toward the extrusion position shown in FIG. 20, the second guided projection 137d passes through the inclined surface 132b from the position of the recess 132a and contacts the inner surface 132c of the second guided rib 132. Accordingly, the second hand pressing portion 137 is elastically deformed inward, and the second holding portion 137c moves inward. Then, at the extrusion position shown in FIG. 20, the first guided projection 136d reaches the position of the recess 131a of the first guide rib 131. Thus, the first hand pressing portion 136 is elastically deformed outward, and the first holding portion 136c moves outward. Accordingly, the hand portions 11, 51 held by the first holding portion 136c are no longer held, and the hand portions 11, 51 are pushed outward by the extrusion plate 124. The hand portions 11, 51 pushed out by the extrusion plate 124 contact the second holding portion 137c where the outermost supported portions 18, 60 are moving inward, stop, and are held.

[0059] In FIG. 21, when the end face cam 121 rotates from the extrusion position shown in FIG. 20 and moves toward the use position shown in FIG. 21, the first guided projection 136d passes through the inclined surface 131c from the position of the recess 131a and contacts the inner surface 131d of the first guide rib 131. Accordingly, the first hand pressing portion 136 is elastically deformed inward, and the first holding portion 136c moves inward. At this time, the first holding portion 136c is inserted between the outermost hand portion 11, 51(11-1) accommodated in the socket rotating portion 122 and the second outermost hand portion 11, 51(11-2). That is, the supported portion 18, 60 of the second outermost hand portion 11, 51(11-2) is held by the first holding portion 136c. Then, at the use position in FIG. 21, when the socket rotating portion 122 rotates, the outermost hand portion 11, 51, that is, the deployed hand portion 11, 51 also rotates, and can grip or suspend an object.

[0060] Therefore, in the robotic arm 1 of the first embodiment, when the motor 102 operates, the sliders 104, 104', 104'' move along the shaft 103. As the sliders 104, 104', 104'' move, the connecting bar 116, the slide rack 114, and the combination gear 117 move and rotate. As the sliders 104, 104', 104'' move toward the tip side, the socket rotating part 122 rotates together with the first gear 118. Therefore, the hand parts 11, 51 supported by the socket rotating part 122 close inward. Therefore, it is possible to grip the object 9 disposed between the first hand parts 11, or insert the gripping part 52 of the second hand part 51 into the handle part 9a of the object 9'.

[0061] When the sliders 104, 104', 104'' move further toward the tip side than the state where the hand parts 11, 51 are closed, the first gear 118 engages with the first idle part 118b, and the drive is transmitted only to the second gear 119, and only the end face cam 121 operates. Therefore, the hand parts 11, 51 are removed. When the hand parts 11, 51 are removed, the hand parts 11, 51 accommodated inside are pushed out to the outside by the push-out plate 124 and shift from the folded state to the unfolded state. Therefore, by operating one motor 102, it is possible to open / close and remove the hand parts 11, 51. Also, it is possible to automatically remove the hand parts 11, 51, and when switching the hand parts 11, 51 or replacing the hand parts 11, 51 contaminated in a sanitary environment, etc., the operator can replace them with new hand parts 11, 51 without touching them.

[0062] In particular, in the robot arm 1 of the first embodiment, a common socket portion 8 can be attached to the base portions 7, 7', 7". Therefore, by making the socket portion 8 common, while reducing costs, it is possible to grip with two or three hand portions 11, 51 according to the shape and size of the objects 9, 9'. Further, for example, only the hand portion 11 is accommodated in one socket portion 8, only the hand portion 51 is accommodated in another socket portion 8, and the hand portion 11 and the hand portion 51 are alternately attached to still another socket portion 8. It is also possible to easily switch the hand portions 11, 51 only by replacing the socket portion 8 according to the application. Note that the hand portions 11, 51 are not limited to those illustrated in the embodiments, and any hand portion can be used as long as the supported portions 18, 60 have a common configuration.

[0063] Furthermore, in the robot arm 1 of the first embodiment, with the operation of one motor 102, it is possible to open and close (grip and release the object 9) the hand portions 11, 51 and also possible to remove them. Therefore, compared with a configuration that uses a separate motor for removal, costs can be reduced. Also, in the robot arm 1 of the first embodiment, it is possible to operate a plurality (two or three) of socket portions 8 with one motor 102, and compared with the case where a motor is provided for each socket portion 8, costs can be reduced.

[0064] (Modified Example) Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Modified examples (H01) to (H05) of the present invention are illustrated below. (H01) In the above embodiment, a configuration in which the robot arm 1 is used for moving an article has been illustrated, but the present invention is not limited to this. For example, it can also be applied to inventory management of the object 9, recognition of the customer's purchase object 9 in a unmanned store, and the like.

[0065] (H02) In the above embodiment, a configuration in which two or three socket portions 8 are attached to the base portions 7, 7', 7" has been illustrated, but the present invention is not limited to this. For example, it is also possible to use four or more. (H03) In the above embodiments, it is desirable to provide reinforcing portions and the like for each of the hand portions 11 and 51, but it is also possible to adopt a configuration without providing them. (H04) In the above embodiments, it is desirable that the hand portions 11 and 51 be formed of a single sheet, but the present invention is not limited thereto. It is also possible to adopt a configuration in which each part is separately formed and assembled. For example, it is also possible to make changes such as forming the gripping portion 12 of a thick sheet material with high rigidity and forming other parts of a thin sheet material.

[0066] (H05) In the above embodiments, it is desirable that a plurality of hand portions 11 and 51 be accommodated in the socket portion 8 and automatically exchanged one after another, but the present invention is not limited thereto. It is also possible to adopt a configuration in which only one hand portion 11 or 51 can be mounted.

Explanation of Reference Numerals

[0067] 1... Object gripping device, 2... Arm portion, 9′... Object, 9a... Gripping portion, 51... Hand portion, 52... Suspension portion, 54... First link portion, 55... First joint portion, 56... Second link portion, 57... Second joint portion, 60... Supported portion, 81... Sheet for assembling hand portion.

Claims

1. A sheet-like hanging part that can contact a handle part of an object and hang the handle part; a first link portion having one end connected to one end of the hanging portion; a second link portion having one end connected to the other end of the first link portion and having the other end of the hanging portion connected thereto; a third link portion that restricts movement of the second link portion when one end of the third link portion is connected to the other end of the second link portion and a handle portion of the object is hung on the hanging portion; a supported portion connected to the other end of the third link portion and supported by a tip portion of an object grasping device; A hand unit comprising:

2. a first joint portion rotatably connecting the other end of the first link portion and one end of the second link portion; a second joint portion rotatably connecting the other end of the second link portion and one end of the supported portion; Equipped with The first joint portion and the second joint portion are rotated to deform between a folded state in which the first link portion and the second link portion face each other and are close to each other and the second link portion and the supported portion face each other and are close to each other across the first link portion, and an unfolded state in which the first link portion, the second link portion, and the supported portion are separated from each other. The hand unit according to claim 1 .

3. The hanging portion, the first link portion, the second link portion and the supported portion are formed by folding a single sheet. The hand unit according to claim 2 .

4. the first joint portion and the second joint portion have a spring property that applies a force for transitioning from the folded state to the unfolded state by an elastic restoring force of the seat; The hand portion according to claim 3 .

5. a hand unit having a sheet-like hanging unit capable of contacting a handle unit of an object to hang the handle unit, a first link unit having one end connected to one end of the hanging unit, a second link unit having one end connected to the other end of the first link unit and the other end connected to the hanging unit, and a supported unit having one end connected to the other end of the second link unit; an arm portion having a socket portion at a tip end thereof for supporting the supported portion, the arm portion moving the hand portion in a direction approaching or moving away from an object; An object gripping device comprising:

6. A hand unit assembly sheet for assembling a hand unit that comes into contact with an object by folding the hand unit, A sheet-like hanging part that can contact a handle part of an object and hang the handle part; a first link portion having one end connected to one end of the hanging portion; a second link portion having one end connected to the other end of the first link portion and having the other end of the hanging portion connected thereto; a supported portion having one end connected to the other end of the second link portion and supported by a tip end of an object grasping device; A sheet for assembling a hand unit, comprising:

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