Robot hand fixture and robot hand

Abstract

To provide a robot hand jig which simplifies a structure of a robot hand as much as possible and uses only power of the robot hand to achieve downsizing, low costs, and good position accuracy.SOLUTION: A robot hand jig 1 holds a workpiece and a tool and includes a pair of facing movable plates 12 each having a positioning part 13 which has a shape capable of engaging with a robot hand 2 and fixes a position of the robot hand jig 1, and a holding part 14 which holds a workpiece; and a base part 11 to which the movable plates are slidably connected through a compression spring 15 and a slider mechanism 16.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a robot hand fixture and a robot hand. [Background technology]

[0002] In recent years, robots have been increasingly used in production equipment to handle small-lot, high-mix production. When changing product types, it is easier to change setups compared to when using conventional production equipment.

[0003] In recent years, robots have become increasingly multi-functional, with a single robot being able to handle multiple workpieces or hold and process tools at the same time.

[0004] When handling workpieces or tools with a robot, the workpieces or tools are often grasped using a robot hand installed at the tip of the robot. When various workpieces or tools need to be grasped by a robot hand, it is often difficult to grasp them with the same hand because the shapes of the workpieces and tools are different. Therefore, multiple robot hands with gripping parts that match the shapes of the workpieces and tools to be grasped may be required.

[0005] One method known for dealing with such cases is to have the robot itself attach a robot hand jig to the robot hand, allowing the shape of the gripping part to be appropriately changed to match the shape of the workpiece or tool to be gripped.

[0006] Patent Document 1 discloses a method for attaching and detaching fingers at the tip of a robot hand, in which a finger exchange device is used to make the finger portion at the tip of the robot hand detachable, allowing the finger shape to be selected.

[0007] Patent Document 2 discloses a method for attaching and detaching a robot hand, in which a shank attached to the hand can be chucked using an air cylinder mechanism provided at the tip of the robot, and by preparing a hand with a shank, the hand can be selected.

[0008] Patent Document 3 discloses a robot hand that can grip a workpiece having an irregular surface by controlling the internal pressure of a gripping bag portion attached to the hand portion. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2013-94930 A [Patent Document 2] Japanese Patent Publication No. 61-214987 [Patent Document 3] JP 2013-220508 A Summary of the Invention [Problem to be solved by the invention]

[0010] However, the technique of Patent Document 1 requires a dedicated finger replacement device and a power source for the device, which is large in size and expensive.

[0011] The technology of Patent Document 2 requires a supply of air pressure to chuck the hand, and therefore has a complex structure.

[0012] The technology in Patent Document 3 is capable of gripping irregularly shaped workpieces, but in order to perform precise movements, has poor positional accuracy.

[0013] In view of the above problems, the present invention aims to provide a robot hand jig and robot hand that are small, low-cost, and have good positioning accuracy by simplifying the structure of the device as much as possible and using only the power of the robot hand. [Means for solving the problem]

[0014] One aspect of the present invention is a robot hand jig for gripping a workpiece or a tool, comprising a pair of opposing movable plates having a positioning portion that is shaped to engage with the robot hand and fixes the position relative to the robot hand, and a gripping portion that grips the workpiece, a compression spring, and a slider mechanism. The movable plate is moved in the direction in which the gripping part opens and closes through the a base portion slidably connected to the base portion; The shape of the positioning portion that engages with the robot hand is provided on the surface of the movable plate that is located in front of the direction in which the gripping portion opens. This is a robot hand jig characterized by the above.

[0015] Another robot hand jig according to the present invention is a robot hand jig for gripping a workpiece or a tool, comprising a pair of opposed movable plates each having a positioning portion shaped to engage with a robot hand and for fixing a position, and a gripping portion for gripping a workpiece, and a base portion to which the movable plates are slidably connected via a compression spring and a slider mechanism; When the positioning unit is gripped by a robot hand, the compression spring is compressed to apply a reaction force to the robot hand. It is characterized by:

[0016] In the above robot hand jig, the base portion may be provided with a catch portion that is engaged with a stand on which the robot hand jig is placed when not in use.

[0017] In the above robot hand jig, the movable plate may have a plurality of gripping portions.

[0018] Another aspect of the present invention is a robot hand that grips any one of the robot hand jigs described above, the robot hand having a positioning engagement portion shaped to engage with the positioning portion. Effect of the Invention

[0019] According to the robot hand fixture of the present invention, the robot hand fixture can be easily and accurately replaced with a single robot hand, and workpieces and tools of various shapes can be grasped with high positional accuracy, making it possible to construct a small, low-cost robot hand. [Brief description of the drawings]

[0020] [Figure 1]FIG. 1 is a schematic diagram showing an example of a robot hand jig according to the present invention. [Diagram 2] FIG. 1 is a schematic diagram showing an example of a robot hand according to the present invention. [Diagram 3] 1A to 1C are schematic diagrams showing a method of using the robot hand jig and the robot hand of the present invention and a method of gripping a workpiece. [Figure 4] 1A and 1B are diagrams showing a state in which a robot hand jig of the present invention and a robot hand are installed on a robot. [Diagram 5] 1A to 1C are schematic diagrams showing a method of gripping a tool by a robot hand jig of the present invention, or a method of gripping a tool by a robot hand. [Figure 6] FIG. 1 is a schematic diagram showing an example of a robot hand jig stand according to the present invention. [Figure 7] 1 is a schematic diagram showing a method of using the robot hand jig and the robot hand jig stand of the present invention. FIG. [Figure 8] FIG. 1 is a structural diagram showing an example of a robot hand jig of the present invention. [Figure 9] 1 is a diagram showing an example of gripping a workpiece using a robot hand jig and a robot hand according to the present invention. FIG. [Figure 10] 1 is a diagram showing an example of gripping a workpiece using a robot hand jig and a robot hand according to the present invention. FIG. [Figure 11] FIG. 13 is a diagram showing an example of gripping a tool using the robot hand of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The embodiments of the robot hand jig and the robot hand according to the present invention will be described with reference to the drawings. The embodiments shown below show devices and methods for embodying the technical ideas of the invention, and do not limit the materials, shapes, structures, arrangements, etc. of the components to the embodiments shown below.

[0022] FIG. 1 is a schematic diagram showing an example of the outline of a robot hand jig of the present invention. FIG. 2 is a schematic diagram showing an example of the outline of a robot hand of the present invention. As shown in the front view of FIG. 1(a) and the side view of FIG. 1(b), the robot hand jig 1 has a shape that engages with the robot hand, in this example, a mountain shape, and a pair of opposed movable plates 12 having a positioning part 13 that fixes the position of the robot hand jig 1 relative to the robot hand and a gripping part 14 that grips a workpiece that is an object to be handled by the robot hand are connected in a slidable manner to a base part 11 by a compression spring 15 and a slider mechanism 16, respectively. In addition, a catch part 17 is disposed on the base part 11. The slider mechanism 16 can be configured by appropriately adopting a known linear motion mechanism such as a linear shaft, a ball guide, a spline, a linear guide, or a ball screw.

[0023] 2, the robot hand 2 has a flange portion 23 that is connected to the robot, and a pair of hand portions 21 can be opened and closed in a closing direction 201 and an opening direction 202. The hand portions 21 are provided on the inside with a positioning engagement portion 22 shaped to engage with the positioning portion 13 of the robot hand jig 1, in this example, a valley-shaped positioning engagement portion 22.

[0024] The positioning engagement portion 22 of the robot hand 2 and the positioning portion 13 of the robot hand jig 1 are not limited to this example, and any shape and structure can be adopted as long as they have shapes that allow engagement with each other. Also, a plurality of such mutually engaging structures may be provided. By forming mutually engaging shapes on the robot hand jig and the robot hand, the robot hand jig can be easily and accurately fixed when the robot hand jig is replaced.

[0025] Figure 3(a) shows the state before the robot hand jig 1 is attached to the robot hand 2, Figure 3(b) shows the state after attachment, and Figure 3(c) shows the state in which the attached robot hand jig 1 is gripping workpiece A.

[0026] As shown in FIG. 3(a), before the robot hand jig 1 is attached to the robot hand 2, it is desirable to set the compression spring 15 in a state in which it is slightly compressed to give it an initial deflection.

[0027] 3(b), by pinching and gripping the movable plate 12 of the robot hand jig 1 with the robot hand 2, the positioning portion 13 of the robot hand jig 1 receiving the spring reaction force 101 is fitted into the positioning engagement portion 22 of the robot hand 2, and the robot hand 2 and the robot hand jig 1 are positioned. At this time, the base portion 11 is not pinched by the robot hand 2.

[0028] By further reducing the opening amount of the hand portion 21 of the robot hand from the state shown in Fig. 3(b), the gap between the movable plates 12 of the robot hand jig 1 also narrows as shown in Fig. 3(c), and the workpiece A can be gripped by the gripping portion 14. At this time, the spring reaction force 101 becomes larger than in the case of Fig. 3(b).

[0029] In the state shown in FIG. 3(c), the robot hand 2 receives a spring reaction force 101 and a gripping reaction force 102, and therefore needs to be able to tolerate these two forces. For this reason, the compression spring 15 is set to a spring constant based on the force required for positioning the robot hand 2 and the robot hand jig 1. The number is selected appropriately by calculating the allowable deflection from the required stroke amount.

[0030] The shape of the compression spring 15 is not limited, but a coil spring or a leaf spring is generally suitable.

[0031] 4, when the robot hand jig 1 is used to grip the workpiece A, the robot hand jig 1 and the workpiece A are connected to the robot 3 via the robot hand 2. Therefore, it is preferable to design the robot hand 2, the robot hand jig 1, and the workpiece A so that the total weight is equal to or less than the transportable weight of the robot 3.

[0032] As shown in Fig. 5(a), when gripping tool B, a robot hand jig 1 attached to a robot hand can grip tool B. Also, as shown in Fig. 5(b), if a positioning part B1 is provided on tool B, tool B can be gripped directly by a robot hand 2.

[0033] 6, the stand 4 for storing and holding the robot hand jig when not in use is provided with a locking portion 41. This locking portion 41 is a part that corresponds to and locks onto the catch portion 17 of the robot hand jig 1, and can engage with the catch portion 17 to fixedly hold the robot hand jig 1.

[0034] FIG. 7(a) shows the robot hand jig 1 in an installed state before being gripped by the robot hand 2, and FIG. 7(b) shows the state after being gripped.

[0035] 7(a), the robot hand jig 1 is placed stationary under its own weight with the catch portion 17 of the robot hand jig 1 fitted into the locking portion 41 of the stand 4 of the robot hand jig. Note that the catch portion 17 of the robot hand jig 1 may be provided in multiple locations corresponding to the locking portions 41 of the stand 4.

[0036] When using the robot hand jig 1, the robot hand jig 1 is first grasped and lifted by the robot hand 2 as shown in FIG. 7(b) before use.

[0037] The method of installing the robot hand jig 1 is not limited to the above, as long as the structure can ensure the positional relationship between the robot 3 and the robot hand jig 1.

[0038] An example of gripping a workpiece using the robot hand jig and robot hand of the present invention will be described in more detail below, but the present invention is not limited to the following example.

[0039] Fig. 8 shows an example of a robot hand jig 1 of the present invention. Fig. 8(a) shows a front view, Fig. 8(b) shows a side view, and Fig. 8(c) shows a bottom view, and explanation will be given using these. A pair of opposed movable plates 12 each having a positioning portion 13 and a gripping portion 14 are slidably connected to a base portion 11 by a compression spring 15 and a slider mechanism 16. In addition, a catch portion 17 is disposed on the base portion 11. Also, each of the grips has a pair of gripping portions 14a and 14b which are different in shape from each other. The compression spring 15 is installed with an initial deflection, for example, in a state where a spring reaction force of about 30 N is generated. In this example, three catch portions 17 are arranged so as to surround the center of gravity of the robot hand jig 1. The total weight of the robot hand jig 1 obtained by this structure was about 760 g.

[0040] Fig. 9 shows the robot hand jig 1 attached to the inside of the robot hand 2, with the workpiece A being gripped by the gripper 14a. Fig. 10 shows the workpiece A being gripped by the gripper 14b. Figs. 9(a) and 10(a) are front views, and Figs. 9(b) and 10(b) are side views. The surface view is shown. The gripping parts 14a and 14b are provided so that the same workpiece A can be gripped at two different positions depending on the situation. The gripping position and direction can be determined taking into consideration the work content for the workpiece A and the controllability of the robot when transporting the workpiece A.

[0041] The weights of the robot hand jig 1 and the robot hand 2 were 760g and 1700g, respectively, for a total of 2460g. For example, if a Universal Robot UR3e robot with a payload capacity of 3000g is used, it can transport a workpiece weighing up to 540g. The weight of workpiece A shown in Figures 9 and 10 is about 60g, and it can be transported without any problems.

[0042] Figure 11 shows a state in which tool B is gripped by robot hand 2. Figure 11(a) shows a front view, and Figure 11(b) shows a side view. In cases where it is not possible to provide a positioning part B1 directly on the tool B, an exterior part B2 that fits the shape of the tool B is attached to the tool B, and the positioning part B1 is provided on the exterior part B2, so that the tool B can be grasped by the robot hand 2. [Explanation of symbols]

[0043] 1. Robot hand fixture 11 Base 12 Movable plate 13 Positioning section 14...grip part 14a...Gripping part 14b...Gripping part 15 Compression spring 16 Slider mechanism 17 Catch part 101 Spring reaction force 102...Gripping reaction force 2. Robot Hand 21 Hand section 22 Positioning engagement portion 23 Flange section 201...Closing direction 202...Opening direction 3. Robot 4. Robot hand fixture stand 41 .... Locking portion A...Work B Tools B1: Positioning part B2 Tool Case

Claims

1. A robot hand fixture for gripping a workpiece or a tool, A pair of opposed movable plates each having a positioning portion that is shaped to engage with a robot hand and fixes a position, and a gripping portion that grips a workpiece; a base portion to which the movable plate is connected via a compression spring and a slider mechanism so as to be slidable in a direction in which the gripping portion opens and closes; Equipped with A robot hand jig, characterized in that the shape of the positioning portion that engages with the robot hand is provided on a surface of the movable plate that is located forward in the direction in which the gripping portion opens.

2. A robot hand fixture for gripping a workpiece or a tool, comprising: A pair of opposed movable plates each having a positioning portion that is shaped to engage with a robot hand and fixes a position, and a gripping portion that grips a workpiece; a base portion to which the movable plate is slidably connected via a compression spring and a slider mechanism; Equipped with A robot hand jig characterized in that, when the positioning portion is grasped by the robot hand, the compression spring contracts to apply a reaction force to the robot hand.

3. 3. A robot hand jig according to claim 1, wherein the base portion is provided with a catch portion for engaging with a stand on which the robot hand jig is placed when not in use.

4. 3. The robot hand jig according to claim 1, wherein the movable plate has a plurality of gripping portions.

5. A robot hand that grasps the robot hand jig described in claim 1 or 2, characterized in that it has a positioning engagement portion shaped to engage with the positioning portion.

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