JP2024034873A - gripping device - Google Patents

Abstract

An object of the present invention is to provide a gripping device that is compact and can increase the stroke of a gripper. A gripping device 10 includes a drive source 12, rotating bodies 20a and 20b connected to the drive source 12, and one longitudinal end rotatably connected to a portion other than the center of the rotating bodies 20a and 20b. the driving members 28a, 28b, the grips 32a, 32b connected to the other ends of the driving members 28a, 28b in the longitudinal direction, and the driving members 28a, 28b such that they are slidable in the longitudinal direction. 28a, 28b and rotatable sliding receiving parts 36a, 36b. [Selection diagram] Figure 1

Description

The present invention relates to a gripping device.

The gripping device is attached to the tip of the arm of the robot, grips a target article such as a semiconductor, and transports the target article gripped by the gripping device by movement of the arm of the robot. As such a gripping device, those described in Patent Documents 1 to 3 are known, for example.

Japanese Patent Application Publication No. 2005-161454 Japanese Patent Application Publication No. 2021-175591 JP2021-120179 direction

However, the gripping device described in Patent Document 1 is configured such that an arm member is connected to a piston that moves in the vertical direction, and the gripping body is moved left and right by rotation of this arm member, so that the gripping body can be moved from side to side. is limited to a small amount. Furthermore, since the gripping device described in Patent Document 2 is configured to move the gripping body by connecting it to a linearly moving actuator, the gripping device described in Patent Document 1 has a stroke of the gripping body. is limited. Furthermore, the gripping device described in Patent Document 3 is configured to convert the drive of a linearly moving actuator into movement of the gripping body via a cam mechanism, so the device is large due to the provision of the cam mechanism. I have no choice but to.

SUMMARY OF THE INVENTION An object of the present invention is to provide a gripping device that is compact and capable of increasing the stroke of a gripper.

A first aspect of the present invention includes a driving source, a rotating body connected to the driving source, a driving member having one longitudinal end rotatably connected to a portion other than the center of the rotating body, and a rotating body of the driving member. The gripping device includes a gripping body connected to the other end in the longitudinal direction, and a rotatable sliding receiving part that receives the driving member so that the driving member can slide in the longitudinal direction.

A second aspect of the present invention is the gripping device according to the first aspect, further including a parallel movement mechanism that moves the gripping body in parallel.

A third aspect of the present invention is the gripping device according to the first aspect or the second aspect, wherein the drive source and the rotating body are connected via a worm gear.

A fourth aspect of the present invention is the gripping device according to the third aspect, wherein the rotating body is constituted by a worm wheel that meshes with the worm gear.

A fifth aspect of the present invention is the gripping device according to the third or fourth aspect, wherein two of the rotating bodies are arranged with the worm gear in between, and the gripping body is connected to each of them via the drive member. .

According to the present invention, one end of the driving member is connected to the rotating body and the other end is connected to the gripping body, and the driving member is received by the rotatable sliding receiving part so that the driving member is slidable in the axial direction. As a result, the entire device is compact and the stroke of the gripping body can be increased.

FIG. 1 is a front view showing a gripping device according to an embodiment of the present invention. FIG. 3A is a front view of the gripping device according to an embodiment of the present invention, and FIG. FIG. 3A shows a state in which the gripping member of the gripping device according to the embodiment of the present invention is opened to the maximum extent except for the front side fixing plate, and FIG. 3A is a front view and FIG.

Next, embodiments for carrying out the present invention will be described with reference to the drawings. 1 to 3 illustrate a gripping device 10 according to an embodiment of the invention. 1 to 3, the vertical direction of the paper is the Z direction, the direction perpendicular to the Z direction, the horizontal direction of the paper is the X direction, the Z direction, and the direction perpendicular to the X direction, which is perpendicular to the paper. is the Y direction.

The gripping device 10 is attached to the tip of a robot arm, for example in the Z direction. A motor 12 as a drive source is arranged at the upper part of the gripping device 10 in the Z direction. The motor 12 includes a servo motor, a stepping motor, and the like.

The motor 12 is fixed to the motor attachment part 14 in the -Z direction. Furthermore, a motor shaft 16 protrudes from the center of the motor 12 in the −Z direction. The motor shaft 16 is rotatably supported by the motor mounting portion 14 . This motor shaft 16 protrudes from the motor mounting portion 14 in a direction −Z, and a worm gear 18 is fixed to this protruding portion. A bearing portion 19 is provided further in the -Z direction of the worm gear 18, and the motor shaft 16 is rotatably supported by this bearing portion 20. Worm gear 18 rotates around the Z axis.

Wall wheels 20a and 20b as rotating bodies are arranged on both sides of the worm gear 18 in the X direction. The worm gear 18 and the wall wheels 20a, 20b mesh in the X direction. The wall wheels 20a, 20b rotate around rotating shafts 22a, 22b located at the center of the wall wheels 20a, 20b. The rotating shafts 22a, 22b are connected to a front side fixing plate 24 (shown in FIG. 1, but not shown in FIGS. 2 and 3) provided to sandwich the wall wheels 20a, 20b in the Y direction, and a rear side fixing plate 24 (shown in FIG. It is rotatably supported by a fixed plate 26.
In the drawings, if there are two identical parts, a will be assigned to the number of the part placed in the +X direction, and b will be given to the number of the part placed in the -X direction.

The front side fixing plate 24 and the back side fixing plate 26 are fixed to each other. Further, the front-side fixing plate 24 and the back-side fixing plate 26 are fixed to the motor mounting portion 14 and bearing portion 19 described above.

The drive members 28a, 28b extend in the longitudinal direction and are formed into a shaft shape with a circular cross section, for example, and one end of the drive members 28a, 28b is rotatably attached to the worm wheels 20a, 20b via the first drive member support shafts 30a, 30b. is connected to. The first drive member support shafts 30a, 30b are provided at locations other than the centers of the worm wheels 20a, 20b. When the worm wheels 20a, 20b rotate, the first drive member support shafts 30a, 30b revolve around the rotation axes 22a, 22b of the worm wheels 20a, 20b while rotating relative to the worm wheels 20a, 20b. As shown in FIGS. 2(a) and 3(a), the first drive member support shafts 30a, 30b are arranged at an angle of approximately 90 degrees above the rotation shafts 22a, 22b of the worm wheels 20a, 20b in the Z direction, for example. Rotate.

Further, the other longitudinal ends of the drive members 28a, 28b are connected to grips 32a, 32b via third links 48a, 48b, which will be described later. That is, the third links 48a, 48b are provided with second drive member support shafts 34a, 34b, and the other longitudinal ends of the drive members 28a, 28b are rotatably connected to the second drive member support shafts 34a, 34b. Furthermore, grips 32a and 32b are fixed to the third links 48a and 48b.

Further, the intermediate portions in the longitudinal direction of the driving members 28a, 28b are received by sliding receiving portions 36a, 36b so as to be slidable in the longitudinal direction of the driving members 28a, 28b. That is, the sliding receiving parts 36a, 36b are formed in a cylindrical shape, and the driving members 28a, 28b are inserted into the cylindrical sliding holes formed inside the sliding receiving parts 36a, 36b. , 28b are slidably supported by the sliding receiving portions 36a, 36b.

As shown in FIGS. 2(b) and 3(b), the sliding receiving parts 36a and 36b are rotated by the sliding receiving part support plate 40 and the back side fixing plate 26 by the sliding receiving part support shafts 38a and 38b. freely supported. The sliding receiving part support plate 40 is fixed to the motor mounting part 14. One end of the sliding receiving portions 36a, 36b rotates around the rotating shafts 22a, 22b of the worm wheels 20a, 20b via the first driving member support shafts 30a, 30b. Since the drive members 28a, 28b rotate around the slide receiver support shafts 38a, 38b while sliding on the slide receivers 36a, 36b, their movement is not hindered by the rotation of the worm wheels 20a, 20b. There is no.

The parallel movement mechanisms 42a, 42b are mechanisms for moving the grips 32a, 32b in parallel. In this embodiment, the parallel movement mechanisms 42a, 42b are composed of first links 44a, 44b, second links 46a, 46b, and third links 48a, 48b. The first links 44a, 44b are provided parallel to the drive members 28a, 28b. Further, one ends of the first links 44a, 44b are rotatably connected to the second links 46a, 46b via first link upper support shafts 50a, 50b. Further, the other ends of the first links 44a, 44b are connected to third links 48a, 48b via first link lower support shafts 52a, 52b. The distance between the centers of the first link upper support shafts 50a, 50b and the centers of the first link lower support shafts 52a, 52b is the same as the distance between the centers of the first drive member support shafts 30a, 30b and the second drive member support shaft 34a. , 34b.

Further, the second links 46a, 46b and the third links 48a, 48b are provided in parallel. The distance between the center of the first link upper support shafts 50a, 50b and the center of the first drive member support shaft 30a, 30b is the distance between the center of the first link lower support shaft 52a, 52b, the second drive member support shaft 34a, 34b.

Therefore, since the driving members 28a, 28b, the first links 44a, 44b, the second links 46a, 46b, and the third links 48a, 48b form a parallelogram, FIGS. 2(a), (b) and 3( As can be understood by comparing a) and (b), the gripping bodies 32a and 32b are always kept facing each other with respect to the movement of the drive members 28a and 28b.

Note that, as shown in FIG. 2(b), FIG. 3(a), and (b), a guide member 54 is inserted into the second links 46a and 46b. In this embodiment, the guide member 54 is fixed to one second link 46b and is movably inserted into the other second link 46a, and The other second link 46a is guided so that the link 46a moves linearly.

Further, as shown in FIGS. 2(b) and 3(b), cuts 56a and 56b are formed near the inner sides of the sliding receiving part support shafts 38a and 38b of the sliding receiving part support plate 40 described above. is formed. Further, strain gauges 58a and 58b are provided so as to straddle the cuts 56a and 56b. As is well known, the strain gauges 58a and 58b are constructed of Wheatstone bridge circuits and detect strain. In this embodiment, the gripping bodies 32a, 32b move from the expanded state shown in FIG. The receiving part support shafts 38a, 38b receive a force in the direction of spreading in the X direction, and this force causes the cuts 56a, 56b to strain in the direction of spreading in the X direction.The strain is detected by the strain gauges 58a, 58b. The gripping force of the gripping bodies 32a and 32b can be detected by the output of the gripper 58b.

In the above configuration, as shown in FIGS. 2A and 2B, when the motor 12 is driven from a state where the grips 32a and 32b want to be closed, the worm gear 18 rotates together with the motor shaft 16 around the Z axis. When the worm gear 18 rotates around the Z-axis, the worm wheels 20a, 20b that mesh with the worm gear 18 rotate around the Y-axis around the rotating shafts 22a, 22b. That is, one worm wheel 20a rotates clockwise around the rotating shaft 22a, and the other worm wheel 20b rotates counterclockwise around the rotating shaft 22b. When the worm wheels 20a, 20b rotate, the first drive member support shafts 30a, 30b also rotate about the rotation shafts 22a, 22b.

When the first drive member support shafts 30a, 30b similarly rotate around the rotation shafts 22a, 22b, one end of the drive members 28a, 28b rotates in an arc shape; The slide receiving parts 36a, 36b rotate about the sliding receiving part support shafts 38a, 38b while sliding on the sliding receiving parts 36a, 36b, so that their movement is not hindered.

When the sliding receiving parts 36a, 36b rotate around the sliding receiving part support shafts 38a, 38b while the driving members 28a, 28b slide on the sliding receiving parts 36a, 36b, the third links 48a, 48b and the grip The motor 12 stops at the stage when the bodies 32a and 32b are expanded in the X direction and are expanded to the states shown in FIGS. 3(a) and 3(b).

Next, in order to grip the target article placed between the grippers 32a and 32b, the rotation direction of the motor shaft 16 of the motor 12 is reversed from the state shown in FIGS. 3(a) and 3(b) and the motor 12 is rotated. When the motor shaft 16 rotates in the opposite direction, the worm gear 18 rotates in the opposite direction, and the worm wheels 20a, 20b rotate in the opposite direction about the rotating shafts 22a, 22b. When the worm wheels 20a, 20b rotate in the opposite direction, the drive members 28a, 28b move, and the grips 32a, 32b move in the direction of narrowing and hit the target article. When the gripping bodies 32a, 32b hit the target object, the strain gauges 56a, 56b detect the gripping force of the gripping bodies 32a, 32b, and when the target gripping force is obtained, the motor 12 is stopped and the target article is gripped. complete.

When opening and closing the gripping bodies 32a, 32b in this manner, since the parallel movement mechanisms 42a, 42b are connected to the drive members 28a, 28b, the gripping bodies 32a, 32b can be moved in parallel, and the target object can be easily grasped.

As described above, in the above embodiment, the worm wheels 20a, 20b are connected to the worm gear 18, and the worm wheels 20a, 20b and the grips 32a, 32b are slidably and Since they are connected by rotatably supported drive members 28a and 28b, the gripping device 10 can be downsized, and although the gripping force of the gripping bodies 32a and 32b on the target component is small, the stroke of the gripping bodies 32a and 32b is small. can be made larger.

In the above embodiment, two rotating bodies are used to move the two gripping bodies, but in other embodiments, one gripping body is fixed and one rotating body is used to move the two gripping bodies. The object article may be gripped by moving one gripper.

10 Gripping device 12 Motor 14 Motor mounting part 16 Motor shaft 18 Worm gear 19 Bearing part 20a, 20b Worm wheel 22a, 22b Rotating shaft 22a Rotating shaft 24 Front side fixing plate 26 Back side fixing plate 28a, 28b Drive member 30a, 30b Drive member Support shafts 32a, 32b Grips 34a, 34b Drive member support shafts 36a, 36b Sliding receivers 38a, 38b Sliding receiver support shafts 40 Sliding receiver support plates 42a, 42b Parallel movement mechanism 44a, 44b First link 46a , 46b Second link 48a, 48b Third link 50a, 50b First link upper support shaft 52a, 52b First link lower support shaft 54 Guide member 56a, 56b Notch 58a, 58b Strain gauge

Claims (5)

A driving source,
a rotating body connected to the drive source;
a driving member having one longitudinal end rotatably connected to a portion other than the center of the rotating body;
a gripping body connected to the other longitudinal end of the driving member;
a sliding receiving part that receives the driving member so that the driving member is slidable in a longitudinal direction and is rotatable;
A gripping device having a The gripping device according to claim 1, further comprising a parallel movement mechanism that moves the gripping body in parallel. The gripping device according to claim 1, wherein the drive source and the rotating body are connected via a worm gear. 4. The gripping device according to claim 3, wherein the rotating body includes a worm wheel that meshes with the worm gear. 4. The gripping device according to claim 3, wherein two of the rotating bodies are arranged with the worm gear in between, and the gripping body is connected to each of them via the drive member.