Robot hand

Abstract

To provide a robot hand which can prevent the position of a hand part from undesirably varying and down-size.SOLUTION: A robot hand 1 comprises an oscillation-type actuator 4, an angle adjustment mechanism 5 which adjusts the rotation angle of the oscillation-type actuator 4, and a hand part 3 connected to the oscillation-type actuator 4 via a hand connection member 6. The angle adjustment mechanism 5 includes: a cam member 8, provided on the shaft 4b of the oscillation-type actuator 4; and an adjuster 9, provided on the actuator body 4a of the oscillation-type actuator 4 to be capable of separating from, and contacting with the cam faces 8a, 8a of the cam members 8. The cam member 8 and the hand connection member 6 are integrally provided. The adjuster 9 has an adjustment screw 4 which contacts the cam faces 8a, 8a and an adjustment screw mounting member 11 which mounts this adjustment screw 4.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a robot hand having an oscillating actuator used, for example, at the tip of an industrial robot or the like.

Background Art

[0002] As the oscillating actuator, for example, a rotary actuator has been proposed which includes a shaft oscillating mechanism in which a vane is swingably provided via a vane shaft in an oscillating chamber within an actuator main body to oscillate the vane shaft by fluid pressure, and a stroke adjusting mechanism for adjusting the oscillating stroke of the vane shaft (Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the mechanism of Patent Document 1 is used on one shaft of an oscillating actuator with both shafts of the vane shaft protruding to implement an angle adjustment function, a hand connection member for connecting the hand portion to the other shaft and a sensor for detecting rotation are to be attached. For this reason, the robot hand becomes large in the axial direction of the oscillating actuator. If the cam member fixed to the vane shaft and the hand connection member are separate bodies, when a fixation deviation occurs between the cam member and the vane shaft due to impact or the like, the start point and end point of the operation of the hand portion change. For this reason, the hand portion may interfere with other members or equipment, and the apparatus to which the robot hand is attached may stop.

[0005] The object of the present invention is to provide a robot hand that prevents the position of the hand from changing undesirably and that can be miniaturized. [Means for solving the problem]

[0006] The robot hand of the present invention comprises a rocking actuator and An angle adjustment mechanism for adjusting the rotation angle of the aforementioned oscillating actuator, The swing-type actuator comprises a hand portion connected to the swing-type actuator via a hand connection member, The angle adjustment mechanism includes a cam member provided on the shaft of the oscillating actuator and an adjustment tool provided on the actuator body of the oscillating actuator, which is capable of contacting and separating from the cam surface of the cam member. The cam member and the hand connection member are provided integrally. The phrase "integrally provided" means that the cam member and the hand connection member are in a state where they do not become misaligned or loose due to vibration, movement, etc.

[0007] With this configuration, since the cam member and the hand connection member are integrally mounted, positional misalignment between the cam member and the hand connection member caused by the movement of the robot hand is eliminated. This prevents the hand's position from changing undesirably. Therefore, interference between the hand and other components or equipment can be prevented. Furthermore, because the cam member and the hand connection member are integrally mounted, the angle adjustment mechanism and the hand connection member can be implemented on one axis side of the oscillating actuator. In this case, it becomes possible to reduce the overall axial size of the robot hand compared to conventional structures where the angle adjustment mechanism is mounted on one axis side and the hand connection member is mounted on the other axis side.

[0008] The adjustment device comprises an adjustment screw that contacts the cam surface and an adjustment screw mounting member for attaching the adjustment screw, and this adjustment screw mounting member may be provided separately on the actuator body. In this case, even if the cam member and the hand connection member are integrated, the range of motion of the hand can be easily changed by providing various adjustment screw mounting members that allow the orientation of the adjustment screw to be changed. This increases the versatility of the robot hand. Since the adjustment screw mounting member is provided separately on the actuator body, the processing of the actuator body is simplified, and manufacturing costs can be reduced. By changing the mounting angle of the adjustment screw, the range of motion of the hand can be significantly changed even after the robot hand has been assembled.

[0009] The adjustment device comprises an adjustment screw that contacts the cam surface and an adjustment screw mounting member for attaching the adjustment screw, and this adjustment screw mounting member may be integrally provided with the actuator body. In this case, the adjustment screw mounting member is more resistant to impact than in a structure where the adjustment screw mounting member is provided separately from the actuator body, making it less likely for the starting and ending points of the oscillation to shift.

[0010] The angle adjustment mechanism may be provided with multiple positioning means for positioning the cam surface of the cam member and the adjustment tool in one direction and the other direction of oscillation. In this case, by providing multiple positioning means, the cam surface and the adjustment tool can be positioned in one direction and the other direction of oscillation, thereby simplifying the structure of the angle adjustment mechanism and reducing manufacturing costs.

[0011] The adjusting tool may be provided on one surface of the actuator body near the shaft and may be brought into contact with the cam surface at a position where the rotational moment of the hand portion is less than or equal to a predetermined value. The aforementioned specified values ​​are arbitrarily determined through design, etc., and are determined by finding appropriate values ​​through, for example, testing and simulation, or both. In this case, the impact acting on the cam surface of the adjuster and cam member can be mitigated, thereby increasing the durability of the robot hand. Effects of the Invention

[0012] The robot hand of the present invention includes an oscillating actuator, an angle adjustment mechanism that adjusts the rotation angle of the oscillating actuator, and a hand portion connected to the oscillating actuator via a hand connection member, wherein a cam member of the angle adjustment mechanism and the hand connection member are integrally provided. This makes it possible to prevent the position of the hand portion from changing undesirably and to reduce the size of the robot hand. Brief Description of the Drawings

[0013] [Figure 1] It is a perspective view of the robot hand according to the first embodiment of the present invention. [Figure 2] It is a front view showing one aspect of the angle adjustment mechanism of the same robot hand. [Figure 3] It is a front view showing another aspect of the angle adjustment mechanism of the same robot hand. [Figure 4] It is a perspective view of a robot hand in which a part of the same angle adjustment mechanism is partially modified. [Figure 5] It is a front view showing one aspect of the angle adjustment mechanism of the same robot hand. [Figure 6] It is a front view showing another aspect of the angle adjustment mechanism of the same robot hand. [Figure 7] It is a perspective view of the robot hand according to the second embodiment of the present invention. [Figure 8] It is a front view showing one aspect of the angle adjustment mechanism of the same robot hand. [Figure 9] It is a front view showing another aspect of the angle adjustment mechanism of the same robot hand. Modes for Carrying Out the Invention

[0014] [First Embodiment] The robot hand according to the embodiment of the present invention will be described with reference to Figures 1 to 3. <Schematic Configuration of the Entire Robot Hand> As shown in Figure 1, the robot hand 1 is attached to, for example, the distal end of the arm portion 2 (Figure 2) of an industrial robot. As the industrial robot, for example, a vertical articulated robot or a horizontal articulated robot can be applied. The robot hand 1 includes a swing-type actuator 4 which is a drive source for changing the rotation angle of the hand portion 3, an angle adjustment mechanism 5 for adjusting the rotation angle of the swing-type actuator 4, and the hand portion 3 connected to the swing-type actuator 4 via a hand connection member 6. For example, after gripping the workpiece W with the hand portion 3 at a predetermined position as shown in Figure 2, the posture of the workpiece W can be changed as shown in Figure 3, and the workpiece W can be placed at a predetermined position.

[0015] <swing-type actuator> The swing-type actuator 4 in Figure 1 operates using a fluid such as compressed air, for example. The swing-type actuator 4 is, for example, a vane-type actuator including an actuator main body 4a having a rectangular parallelepiped shape and provided with a swing chamber, and a shaft 4b having a vane that rotatably swings within the swing chamber. The swing-type actuator 4 is also referred to as a rotary actuator. The shaft 4b protrudes by a predetermined length in one axial direction C1 from the housing that is the actuator main body 4a. The swing-type actuator 4 has an operating range that is greater than the range adjustable by the angle adjustment mechanism 5. A mechanism (not shown) that limits the operating angle may be provided inside the swing-type actuator 4.

[0016] <hand portion> The hand portion 3 is capable of detachably holding a predetermined workpiece, and in the present embodiment, a parallel chuck that causes the gripping portions 7, 7 to open and close with compressed air is applied. The hand portion 3 is rotatably connected to the shaft 4b of the swing-type actuator 4, and the swing-type actuator 4 changes the rotation angle of the hand portion 3. The parallel chuck includes a chuck main body 3a, and gripping portions 7, 7 that are supported at the distal end portion of the chuck main body 3a so as to be parallel and slidable. The parallel chuck allows the workpiece to be attached and detached by the gripping portions 7, 7. In addition to the parallel chuck, the hand portion 3 can employ a chuck operated by compressed air such as a three-jaw or four-jaw chuck (not shown), a suction pad, an electric hand, or the like.

[0017] <Regarding angle adjustment mechanism, etc.> The angle adjustment mechanism 5 includes a cam member 8 and an adjustment tool 9 that can contact and separate from the cam surfaces 8a, 8a of the cam member 8. The angle adjustment mechanism 5 in this embodiment is provided outside the actuator body 4a. The cam member 8 is fixed to a shaft 4b that protrudes from the actuator body 4a in one axial direction and has a substantially triangular prism shape. The cam member 8 is fixed so as not to rotate relative to the shaft 4b. The bottom surface of the substantially triangular prism shape of the cam member 8 faces one surface of the actuator body 4a, and its two sides form cam surfaces 8a, 8a. As shown in Figures 2 and 3, the cam surfaces 8a, 8a, which are the contact surfaces of the cam member 8, are set to a predetermined angle.

[0018] As shown in Figure 1, the adjustment device 9 is provided on the actuator body 4a. The angle adjustment mechanism 5 is provided with multiple (at least two) adjustment screws 10, which are positioning means for positioning the cam surfaces 8a, 8a of the cam member 8 and the adjustment device 9 in one direction and the other direction of oscillation. Specifically, as shown in Figures 2 and 3, the adjustment device 9 has two adjustment screws 10, 10 that contact the cam surfaces 8a, 8a, and an adjustment screw mounting member 11 to which the two adjustment screws 10, 10 are attached.

[0019] As shown in Figure 1, the adjustment tool 9 is provided on one surface of the actuator body 4a near the shaft 4b, and is brought into contact with the cam surfaces 8a, 8a at a position where the rotational moment of the hand portion 3 is less than or equal to a predetermined value. The predetermined value is a value arbitrarily determined by design, etc., and is determined by finding an appropriate value through either or both of testing and simulation. The adjustment screw mounting member 11 is provided separately from the actuator body 4a. Specifically, the adjustment screw mounting member 11 is detachably attached to one surface of the actuator body 4a by a plurality of bolts 12. Through holes are provided parallel to the axial direction at both longitudinal ends of the adjustment screw mounting member 11, through which each bolt 12 is inserted. The actuator body 4a is provided with female threads into which each bolt 12 inserted through the through holes is screwed.

[0020] The adjustment screw mounting member 11 is provided with female threads for attaching, that is, for supporting, two adjustment screws 10, 10 so that they can move freely. In the adjustment screw mounting member 11 of this embodiment, the adjustment screws 10, 10 are arranged parallel to each other at a predetermined distance apart and perpendicular to the axial direction. Each adjustment screw 10 is, for example, a set screw with a hexagonal socket, and the length of the adjustment screw 10 protruding from the adjustment screw mounting member 11 can be changed by inserting a tool into the hexagonal socket and rotating it. As shown in Figures 2 and 3, the operating angle of the robot hand 1 is determined by the contact between the cam surfaces 8a, 8a of the cam member 8 and the tip surfaces 10a, 10a of the two adjustment screws 10, 10 attached to the adjustment screw mounting member 11.

[0021] As shown in Figure 1, the cam member 8 and the hand connecting member 6 are integrally provided. Specifically, the hand connecting member 6 is formed in the shape of a long plate protruding from one side of the cam member 8 adjacent to the cam surfaces 8a, 8a. The hand connecting member 6 is integrally provided on the aforementioned side of the cam member 8. These cam member 8 and hand connecting member 6 are made of a single material, such as a non-ferrous metal such as aluminum or a steel plate. The phrase "integrally provided" means, in principle, that the cam member 8 and the hand connecting member 6 are not made by joining multiple elements with bolts or the like, but are formed from a single material, for example, by forging, machining, etc., as part of or as a whole of a single object. However, this also includes cases where multiple elements are integrated by welding, casting, insert molding, etc.

[0022] As shown in Figures 2 and 3, the angle between the hand connecting member 6 and the adjustment screw 10 is designed so that the cam surface 8a, which is the contact surface of the cam member 8, and the tip surface 10a of the adjustment screw 10 are parallel to each other when in contact. This reduces the pressure when the contact surface of the cam member 8 and the tip surface 10a of the adjustment screw 10 are in contact, and also prevents deviations in the operating angle of the robot hand 1 due to repeated use.

[0023] As shown in Figure 1, to prevent the adjustment screws 10 from loosening due to impact and vibration when the cam member 8 and the adjustment screws 10 come into contact, it is advisable to either fix the adjustment screws 10 with nuts 13, apply a thread locker to the adjustment screws 10, or do both. Alternatively, each adjustment screw 10 may be firmly fixed with two nuts. To avoid interference between the integrated cam member 8 and hand connection member 6 and the adjustment screws 10, the position where the adjustment screws 10 are installed can be changed by the design of the cam member 8 in the integrated cam member 8 and hand connection member 6.

[0024] Counterbore portions 14 are formed on the longitudinal tip and longitudinal middle portion of the surface of the hand connecting member 6, and through holes parallel to the axial direction C1 are provided near the center of each counterbore portion 14. One side surface of the chuck body 3a is provided with a female thread into which each bolt 15 inserted through the through hole is screwed. In this way, the hand portion 3 is fixed to the hand connecting member 6.

[0025] <Effects and Effects> As described above, with the robot hand 1, since the cam member 8 and the hand connecting member 6 are integrally provided, the phase difference, or positional misalignment, between the cam member 8 and the hand connecting member 6 caused by the movement of the robot hand 1 is eliminated. This prevents the position of the hand part 3 from changing undesirably. Therefore, interference between the hand part 3 and other members or equipment can be prevented. Furthermore, because the cam member 8 and the hand connecting member 6 are integrally provided, the angle adjustment mechanism 5 and the hand connecting member 6 can be mounted on one axis 4b side of the oscillating actuator 4. In this case, it is possible to make the robot hand as a whole more compact in the axial direction compared to conventional structures in which the angle adjustment mechanism is mounted on one axis side and the hand connecting member is mounted on the other axis side.

[0026] The adjustment tool 9 has adjustment screws 10, 10 that contact the cam surfaces 8a, 8a, and an adjustment screw mounting member 11 to which the adjustment screws 10, 10 are attached. The adjustment screw mounting member 11 is provided separately on the actuator body 4a. Therefore, even if the cam member 8 and the hand connection member 6 are integrated, the operating range of the hand 3 can be easily changed by providing various adjustment screw mounting members 11 that can change the orientation of the adjustment screws 10. This increases the versatility of the robot hand 1. Because the adjustment screw mounting member 11 is provided separately on the actuator body 4a, the processing of the actuator body 4a is simplified, and manufacturing costs can be reduced.

[0027] The angle adjustment mechanism 5 is provided with multiple adjustment screws 10, which are positioning means for positioning the cam surfaces 8a, 8a of the cam member 8 and the adjustment tool 9 in one direction and the other direction of oscillation. By providing multiple adjustment screws 10, the cam surfaces 8a, 8a and the adjustment tool 9 can be positioned in one direction and the other direction of oscillation, thereby simplifying the structure of the angle adjustment mechanism 5 and reducing manufacturing costs.

[0028] The adjustment tool 9 is provided on one surface of the actuator body 4a near the axis 4b, and is brought into contact with the cam surfaces 8a, 8a at a position where the rotational moment of the hand portion 3 is less than or equal to a predetermined value. In this case, the impact acting on the cam surfaces 8a, 8a of the adjustment tool 9 and the cam member 8 can be mitigated, thereby increasing the durability of the robot hand 1.

[0029] <Regarding other embodiments> In the following description, parts corresponding to matters previously described in each embodiment will be denoted by the same reference numerals, and redundant explanations will be omitted. When only a part of the configuration is described, the other parts of the configuration will be the same as those in the previously described embodiment unless otherwise specified. Identical configurations will produce the same effects. Not only are combinations of the parts specifically described in each embodiment possible, but partial combinations of embodiments are also possible, provided that there are no particular problems with the combination.

[0030] [Modified forms of the angle adjustment mechanism: Figures 4-6] Figure 4 shows that the operating range of the hand part 3 can be greatly changed by changing the mounting angle of the adjustment screw 10. In this modified configuration, the operating range of the hand part 3 is set to 60 degrees, as shown in Figures 5 and 6 when the angle adjustment mechanism 5 is in operation. The adjustment screw mounting member 11A in Figure 4 is arranged so that the two adjustment screws 10, 10 are separated by a predetermined distance, move closer to each other as they approach the tip surface, are non-parallel to each other, and are perpendicular to the axial direction C1.

[0031] By simply changing the adjustment screw mounting member 11 (Figure 1) of the first embodiment to the adjustment screw mounting member 11A as shown in Figure 4, the operating range of the hand portion 3 can be easily changed. This increases the versatility of the robot hand 1. By changing the mounting angle of the adjustment screw 10, the operating range of the hand portion 3 can be significantly changed even after the robot hand 1 has been assembled. In this modified form, only changing the operating range of the hand portion 3 to 60 degrees is shown, but the operating range of the hand portion 3 can be arbitrarily changed by changing the mounting angle of the adjustment screw 10. Other modified forms of the robot hand 1 have the same configuration as the first embodiment and provide the same effects as the first embodiment.

[0032] [Second embodiment: Integrated adjustment screw mounting member, Figures 7-9] As shown in Figure 7, the adjustment tool 9 has adjustment screws 10, 10 that contact the cam surfaces 8a, 8a, and an adjustment screw mounting member 11B to which these adjustment screws 10, 10 are attached. This adjustment screw mounting member 11B may be integrally provided with the actuator body 4a. Specifically, the adjustment screw mounting member 11B is formed in the shape of a rectangular plate that protrudes axially from the right side of one surface of the actuator body 4a as shown in Figure 7. The adjustment screw mounting member 11B is integrally provided with the aforementioned surface of the actuator body 4a.

[0033] These actuator bodies 4a and adjustment screw mounting members 11B are made of a single material, such as aluminum or steel plate. The phrase "integrally provided" means, in principle, that the actuator body 4a and adjustment screw mounting members 11B are not made by joining multiple elements with bolts or the like, but are formed from a single material, for example, by forging, machining, etc., as part of or as a whole of a single object. However, this also includes cases where multiple elements are integrated by welding, casting, insert molding, etc.

[0034] Figures 8 and 9 show the angle adjustment mechanism 5 in operation. With the adjustment screw mounting member 11B integrally provided with the actuator body 4a, the adjustment screw mounting member 11B is more resistant to impact than in a structure where the adjustment screw mounting member is provided separately from the actuator body, making it less likely for the start and end points of the oscillation to shift.

[0035] The angle adjustment mechanism may be provided inside the actuator body. Alternatively, a cover or other covering member may be detachably provided to cover at least a part of the actuator body, so that the angle adjustment mechanism is covered by the covering member. In this case, the covering member can be detached from the actuator body to easily adjust the angle adjustment mechanism, and the movable part of the angle adjustment mechanism can be prevented from being exposed by covering the angle adjustment mechanism with the covering member when the robot hand is in operation.

[0036] In a rocking actuator, the shaft having the vanes may protrude from both axial directions of the housing, which is the actuator body. In this case, an angle adjustment mechanism and a hand connection member can be mounted on one shaft side of the rocking actuator, and a rotation sensor or the like for detecting the rotation angle can be attached to the other shaft side. Oscillating actuators are not limited to vane type; they may also be piston type, and oil can be used as the working fluid. Other types of electrically operated oscillating actuators can also be applied. To reduce the impact when the cam surface (the contact surface of the cam member) and the tip surface of the adjustment screw come into contact, an impact-absorbing member such as an elastic body may be attached to the tip surface of the adjustment screw or the cam surface of the cam member. The adjustment screw may also be used as a shock absorber as a mechanism to reduce impact.

[0037] In a configuration where the adjustment screw mounting member is provided separately from the actuator body, position fixing means such as positioning pins may be provided on the oscillating actuator to prevent misalignment of the mounting position when replacing the adjustment screw mounting member. For example, on one surface of the actuator body 4a in Figure 4, a positioning pin is provided on the mating surface with the adjustment screw mounting member 11A. Multiple positioning pins are provided along the longitudinal direction of the adjustment screw mounting member 11A. Such position fixing means can more reliably and easily prevent misalignment of the mounting position when replacing the adjustment screw mounting member 11A, and the hand portion 3 can be positioned with high precision.

[0038] A robot hand may be attached to the output of an XYZ-shaped linear actuator extending in three orthogonal axes, or to the output of a linear actuator extending in two orthogonal axes.

[0039] While embodiments of the present invention have been described above, the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0040] 1...Robot hand, 3...Hand section, 4...Oscillating actuator, 4a...Actuator body, 4b...Shaft, 5...Angle adjustment mechanism, 6...Hand connecting member, 8...Cam member, 8a...Cam surface, 9...Adjuster, 10...Adjustment screw (positioning means), 11, 11A, 11B...Adjustment screw mounting members

Claims

1. Oscillating actuator and An angle adjustment mechanism for adjusting the rotation angle of the aforementioned oscillating actuator, The oscillating actuator is connected to a hand portion via a hand connecting member, and the hand portion has a chuck body and a gripping portion supported at the tip of the chuck body that allows the workpiece to be attached and detached. The angle adjustment mechanism includes a cam member provided on the shaft of the oscillating actuator and an adjustment tool provided on the actuator body of the oscillating actuator, which is capable of contacting and separating from the cam surface of the cam member. A robot hand in which the cam member and the hand connecting member are integrally provided, the hand connecting member is formed in the shape of a long plate protruding from one side adjacent to the cam surface, and one side of the chuck body is attached to the longitudinal tip of this long plate-shaped hand connecting member.

2. The robot hand according to claim 1, wherein the adjustment device comprises an adjustment screw that contacts the cam surface and an adjustment screw mounting member for attaching the adjustment screw, and the adjustment screw mounting member is provided separately from the actuator body.

3. The robot hand according to claim 1, wherein the adjustment device comprises an adjustment screw that contacts the cam surface and an adjustment screw mounting member for attaching the adjustment screw, and the adjustment screw mounting member is integrally provided with the actuator body.

4. A robot hand according to claim 1 or claim 2, wherein the angle adjustment mechanism is provided with a plurality of positioning means for positioning the cam surface of the cam member and the adjustment tool in one direction of oscillation and in the other direction.

Images