JP5832486B2 - Joint device for parallel robot - Google Patents

Description

  The present invention relates to a joint device used for a parallel robot.

4 and 5 show an example of a conventional parallel robot. This parallel robot includes three support walls 15 connected upright at equal intervals by a triangular horizontal plate, three motors 11 mounted to face each of the support walls 15, and a joint device. The joint device is composed of a total of three arms 10 that are connected to each other by motors 11. Only one arm 10 will be described below.
Each arm 10 includes one link 12 and two rods 13. One end of the link 12 is coupled to the motor 11 so as to be coaxially rotatable about a rotation shaft (not shown) of the motor 11 so as to transmit the power of the motor. In the rod 13, one end of the rod 13 is connected to the other end of the link 12 by a ball joint 132 so that the rod 13 can be interlocked by the power transmitted by the link 12, and the other end of the rod 13 is connected to the bracket 14 by a ball joint 134. . When one end of the link 12 is rotated by the driving force from the motor 11, the rod 13 rotates in a three-dimensional direction with respect to the link 12 using the ball joint 132 as a fulcrum, and the bracket 14 is moved by the arm 10. The support wall 15 is moved up and down and moved to the left and right with reference to the support wall 134 (see Patent Document 1).

US Pat. No. 5,333,514

In the parallel robot described above, the ball joint 132 or 134 for connecting the link 12 and the rod 13 or the rod 13 and the bracket 14 is provided with a ball. Since it is provided in a large size, there are problems in that the positioning accuracy due to the movement of the bracket is lowered, and wear is caused by rattling of the ball with respect to the ball housing portion.
An object of this invention is to provide the joint apparatus of the parallel robot which can aim at positioning with high precision.

  In order to achieve the above object, a joint device for a parallel robot according to the present invention is a joint device used for a parallel robot having a plurality of power sources each having a rotation axis serving as a rotation center. A plurality of arms that are connected to each other at a predetermined angular interval so as to be rotationally driven by the corresponding power source; and one bracket that is connected together at the other end of each of the arms. A transmission member connected to and supported by the corresponding power source so as to transmit a driving force from the power source so as to be rotatable in a circumferential direction that is a direction around a central axis along the rotation center; and An interlocking member that is rotatably connected between the transmission member and the bracket, and the transmission member and the interlocking member are connected so as to be interlocked with each other. Thus, the first transmission member is provided so as to be rotatable about a first axis along a second direction perpendicular to the first direction, which is a direction in which the transmission member extends toward the interlocking member. The first axis is parallel to the first direction so that the bearing unit, the first bearing unit, and the corresponding one end of the interlocking member on the transmission member side are coupled to each other. The interlocking member such that two second bearing units rotatably provided around a second axis perpendicular to the axis and the other end of the corresponding interlocking member that is away from the one end are rotatably connected. Two third bearing units rotatably provided around the third axis parallel to the second axis at the other end, the other end of the interlocking member, and the third bearing unit, The bra One fourth bearing unit provided so as to be rotatable about a fourth axis that is parallel to the first axis and perpendicular to the third axis so as to be connected to each other. It is characterized by having.

  According to the joint device of the parallel robot according to the present invention, since the transmission member, the interlocking member, and the bracket are rotatably connected via the corresponding bearing unit, a ball joint is not used as in the conventional case. Since there is no gap for assembly and rolling, there is no wear due to rattling in the gap, and it can be used for a long time. Furthermore, since the gap is not provided, the positioning accuracy due to the movement of the bracket can be greatly increased, so that the machining accuracy can also be improved.

It is an assembly perspective view which shows the structure of the joint apparatus of the parallel robot which concerns on this invention. It is a perspective view which expands and shows a part of joint apparatus of the parallel robot of FIG. It is a disassembled perspective view of the interlocking member in FIG. It is a perspective view which shows an example of the joint apparatus of the conventional parallel robot. FIG. 5 is a partial exploded perspective view of FIG. 4.

EXAMPLE An example of the present invention will be described below with reference to the drawings. Note that the specific terms and expressions used in this specification are not intended to limit the present invention but to provide an understandable description of the present invention.
FIG. 1 is an assembled perspective view showing a configuration of a joint device 100 for a parallel robot according to the present invention. As shown in the figure, the joint device 100 of the parallel robot is used for a parallel robot having a plurality of, for example, three motors 9 as power sources each having a rotation axis (not shown) serving as a rotation center. . The joint device 100 of the parallel robot includes three arms 1, three prestress units 4, and one bracket 5.
In the present embodiment, the motor 9 is illustrated as being used to rotationally drive the arm 1, but the present invention is not limited to this, and the arm 1 may be rotationally driven using, for example, manual power or magnetic force as a power source. In addition, since the connection between the motor 9 and the arm 1 is the same as that of the prior art, detailed description is omitted.
Each arm 1 uses a link structure in which one end of each arm is connected to a corresponding motor 9 so as to be able to be rotated and driven at a predetermined angular interval, and each arm 1 transmits a driving force from the motor 9. A transmission member 2 movably connected to the motor 9, an interlocking member 3 connected to the transmission member 2 so as to be interlocked, and between the transmission member 2 and the interlocking member 3 and between the interlocking member 3 and the bracket 5. And a plurality of bearing units 31, 32, 34, and 35 (see FIG. 3).
The transmission member 2 uses a flat link member, and one end of the transmission member 2 is connected to the corresponding motor 9 so that the driving force from the motor 9 is transmitted. The circumference is a direction around the central axis along the rotation center of the motor 9. It is connected and supported so as to be rotatable in the direction.
2 and 3 together, the interlocking member 3 is rotatably connected between the transmission member 2 and the bracket 5 so as to interlock with the transmission member 2, for example, the first bearing unit. 31 is a direction along the first axis O1 along the second direction O perpendicular to the first direction L, which is the direction extending in the longitudinal direction toward the interlocking member 3 of the transmission member 2. Two rods 33 connected between both ends in the axial direction X1 and both ends in the fourth axial direction X2, which is a direction along the fourth axis O4 of the fourth bearing unit 35, are provided. Have.
The first bearing unit 31 is provided so as to be rotatable about the first axis O1 so that the transmission member 2 and the interlocking member 3 are connected to each other, and a pair of first members connected to each other. Angular ball bearings 311 and 311 and two first bearing frames 312 connected to the corresponding first angular ball bearings 311 so that the second bearing unit 32 is disposed on each of them.
The second bearing unit 32 is parallel to the first direction L and connected to the first direction so that the first bearing unit 31 and one end of the corresponding interlocking member 3 on the transmission member 2 side are connected. It is provided so as to be rotatable about a second axis O2 perpendicular to the axis O1, and passes through the corresponding rod 33 and is connected to the corresponding first bearing frame 312 together with the penetrated rod 33. A first ball bearing 321 is disposed.
The third bearing unit 34 is connected to the other end of the interlocking member 3 so that the other end of the corresponding interlocking member 3 separated from one end and a fourth bearing unit 35 described below are rotatably connected. The second bearing unit 35 of the fourth bearing unit 35 corresponding to the second rod 33 that passes through the corresponding rod 33 and passes through the corresponding rod 33 is provided to be rotatable about a third axis O3 parallel to the second axis O2. A second ball bearing 341 is provided that is connected to the bearing frame 352.
The fourth bearing unit 35 is parallel to the first axis O1 and the third axis O3 so that the other end of the interlocking member 3, the third bearing unit 34, and the bracket 5 are connected. A pair of second angular ball bearings 351 are provided so as to be rotatable around a right-angled fourth axis O4, and the third bearing unit 34 is disposed in each pair. And two second bearing frames 352 connected to each of the second angular ball bearings 351.
The first bearing frame 312 and the second bearing frame 352 are formed to have a U-shaped cross section and open to the rod 33 side so as to sandwich the corresponding rod 33.
In this example, the second bearing unit 32 and the third bearing unit 34 are respectively provided at both ends in the axial direction Z of the rod 33. Further, each of the second bearing units 32 is provided at each of both ends of the first bearing unit in the first axial direction X1 corresponding to the rod 33. The third bearing unit 34 is provided at each end of the fourth bearing unit 35 in the fourth axial direction X2 corresponding to the rod 33.
A plurality of prestress units 4 are provided in accordance with the interlocking member 3 so as to apply prestress to the interlocking member 3, and are provided on both ends in the axial direction Z, which is the direction along the axis center of the rod 33. Each of the prestress modules 41 includes two holding members 411 connected to the two rods 33 at right angles to the axial direction Z, and the two holding members 411. And an elastic member 412 provided to be connected.
In this example, the holding member 411 uses a claw member in which a holding hole is formed so as to hold the corresponding rod 33. In this example, the elastic member 412 uses, for example, a spring member that has a hook shape in which both end portions hook and hold the holding member 411.
When the holding member 411 is pulled by the elastic member 412, the prestress unit 4 is pulled by pulling the rod 33 connected and held by the holding member 411, via the second bearing unit 32 and the third bearing unit 34. The prestress is transmitted to the first bearing unit 31 and the fourth bearing unit 35. In this way, the corresponding first angular ball bearings 311 and the second angular ball bearings 351 can be pushed and closely connected to each other.
As described above, the transmission member 2 and the interlocking member 3, and the interlocking member 3 and the bracket 5 are rotatably connected via the ball bearings 321 and 341, respectively, and the corresponding first angular ball bearings 311 and the first Since the two angular ball bearings 351 can be tightly coupled to each other by the prestress unit 4, the gap between the ball housing portion and the ball in the ball joint 132 or the ball joint 134 as in the prior art is eliminated. It is possible to greatly eliminate wear caused by shakiness and to be used for a long time. Furthermore, according to the joint device 100 of the parallel robot according to the present invention, since there is no gap, the positioning accuracy by the movement of the bracket 2 can be greatly increased, so that the processing accuracy is also improved.

  The joint device for a parallel robot according to the present invention is useful for a parallel robot with high machining accuracy.

100 Joint device 1 of parallel robot 1 Arm 2 Transmission member 3 Interlocking member 31 First bearing unit 311 First angular ball bearing 312 First bearing frame 32 Second bearing unit 321 First ball bearing 33 Rod 34 Third Bearing unit 341 Second ball bearing 35 Fourth bearing unit 351 Second angular ball bearing 352 Second bearing frame 4 Prestress unit 41 Prestress module 411 Holding member 412 Elastic member 5 Bracket 9 Motor L First Direction O second direction O1 first axis O2 second axis O3 third axis O4 fourth axis X1 first axis direction X2 fourth axis direction Z axis direction

Claims (6)

A joint device used for a parallel robot having a plurality of power sources each having a rotation axis serving as a rotation center,
A plurality of arms, each one end of which is connected to be driven to rotate by the power source corresponding to each other at a predetermined angular interval;
A bracket having the other ends of the arms connected together,
Each said arm
A transmission member that is connected and supported by the corresponding power source so as to transmit a driving force from the power source so as to be rotatable in a circumferential direction that is a direction around a central axis along the rotation center;
An interlocking member rotatably connected between the transmission member and the bracket so as to interlock with the transmission member;
A first along a second direction perpendicular to the first direction, which is a direction in which the transmission member extends toward the interlocking member, so that the transmission member and the interlocking member are connected to each other. One first bearing unit rotatably provided about the axis of
The second bearing unit is parallel to the first direction and perpendicular to the first axis so that the first bearing unit is connected to one end of the corresponding interlocking member on the transmission member side. Two second bearing units rotatably provided about the axis of
The other end of the corresponding interlocking member that is separated from the one end is rotatably connected to the other end of the interlocking member about a third axis that is parallel to the second axis. Two third bearing units;
A fourth axis that is parallel to the first axis and perpendicular to the third axis is connected so that the other end of the interlocking member, the third bearing unit, and the bracket are connected. One fourth bearing unit rotatably provided as a center,
Furthermore, each comprises a plurality of prestress units provided so as to apply prestress to the interlocking member corresponding to each interlocking member,
The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
Each of the pre-stress units has two pre-stress modules provided respectively on both end sides in the axial direction that is a direction along the axial center of the rod,
Each of the prestress modules includes two holding members that are connected to each of the two rods at right angles to the axial direction, and an elastic member that is connected between the two holding members. And
The first bearing unit is coupled to each of a pair of first angular ball bearings coupled to each other and the corresponding first angular ball bearings such that the second bearing unit is disposed on each of the first angular ball bearings. Two first bearing frames that are
The fourth bearing unit is coupled to a pair of second angular ball bearings that are coupled to each other and the second angular ball bearing that corresponds to the third bearing unit so that the third bearing unit is disposed respectively. have a two second bearing frame being,
The first bearing frame and the second bearing frame have a U-shaped cross section so as to sandwich the corresponding rod, and are formed to open to the rod side,
By pulling the corresponding rods to each other by the pre-stress module, the pair of first angular ball bearings and the pair of second angular ball bearings are pushed so as to approach each other and tightly contact each other. Concatenated,
A joint device for a parallel robot. The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
Each of the second bearing units has a first ball bearing that is arranged to be connected to the corresponding first bearing frame together with the rod penetrated through the corresponding rod. The joint device for a parallel robot according to claim 1, wherein the joint device is a parallel robot. The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
Each of the third bearing units has a second ball bearing which is disposed in connection with the corresponding second bearing frame together with the rod penetrating through the corresponding rod. The joint device for a parallel robot according to claim 1. The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
The said 2nd bearing unit and said 3rd bearing unit are each provided in the both ends of the axial direction which is a direction along the axial center of the said corresponding rod, respectively. The joint device of the parallel robot described. The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
2. The parallel robot according to claim 1, wherein the second bearing unit is provided at each end of the first bearing unit in the first axial direction corresponding to each of the rods. Joint device. The interlocking member is a direction along each of both ends in the first axial direction, which is a direction along the first axis of the first bearing unit, and along the fourth axis of the fourth bearing unit. Having two rods connected between each of the four axial ends,
2. The parallel robot according to claim 1, wherein the third bearing unit is provided at each of the both ends in the fourth axial direction of the fourth bearing unit corresponding to each of the rods. Joint device.

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