JPS6039092A - Wrist device for robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small wrist device that is provided at the tip of an industrial robot, a positioning device, etc., and is capable of pointing on an n-spherical surface and has a wide operating range.

Wrist devices installed in industrial robots, positioning devices, etc. are required to be as small as possible and have a wide range of motion, depending on the type of work they are being performed on (approaching or inserting into work objects).

In order to expand the range of motion in conventional industrial robot wrist devices for 3-axis rotation, for example, as shown in Figure 1, three concentric input shafts are installed at the tip of R1 of the robot. 2
．． 3.4 and these inputs 11MI2. 3. 4
A first rotation axis 5 degrees concentric with the second rotation axis 6, which is perpendicular to the first rotation axis 5. A third rotating shaft 7 is provided on the second rotating shaft 6 and perpendicular thereto, and by offsetting the axes of these three rotating shafts 5.6.7 to each other, each rotating shaft 5.6.7 The driving force transmission mechanisms 8 of 3 are prevented from interfering with each other.
However, since the three rotating shafts 5, 6, and 7 are provided offset, the wrist device l becomes larger.1. In addition, when moving and positioning the hand unit attached to the wrist device I, it is necessary to make corrections due to offset by operating rotational axes other than the intended rotational axis or the operating axis of the arm of the robot body. We have fixed the problems such as installing dummy points to prevent the joint parts and the supports of each rotating shaft 5, 6, 7 from interfering with the work object, which caused trouble in working in narrow spaces. arise.

Therefore, as shown in FIG. 2, in order to avoid increasing the size of the wrist device due to the offset of the three rotating axes, the first rotating shaft 5. Second rotating shaft6. A mechanism in which the third rotating shafts 7 are arranged orthogonally to each other has also been proposed, and a driving force transmission mechanism using bevel gears etc. 9
Use.

However, such a structure has a structural drawback in that the range in which interference occurs with the bevel gears, etc. of the driving force transmission mechanism 9 of each rotating shaft 5°6.7 is large, and the operating range of the wrist strap R1 is narrowed.

In addition, as shown in FIG. 3, three concentric input shafts 2.
3.4, the first rotating shaft 5 is provided coaxially and the second rotating shaft 6 is provided to diagonally intersect with the first rotating shaft 5.
The third rotating shaft 7 is provided diagonally intersecting with the rotating shaft 6, and the second rotating shaft 6 is disposed diagonally to achieve miniaturization and expansion of the operating range.

However, since the second rotating shaft 6 is arranged diagonally, it is necessary to operate two or three axes for the operation and teaching operations of the hand section attached to the tip of the wrist device, making the operation complicated and the control system complicated. The disadvantage is that

It is an object of the present invention to eliminate such conventional drawbacks, and to provide a robot wrist device that is compact, has a wide range of motion, and has good operability. The configuration of the present invention that achieves this object includes a first rotating shaft that rotates around the concentric input shafts that are driven through three concentrically arranged input shafts, and a first rotating shaft that is orthogonal thereto. In a wrist device for a robot comprising two rotation axes and a third rotation axis perpendicular to the second rotation axes, the robot wrist device is arranged such that the axes of these three rotation axes intersect at one point, wherein the second rotation axis and The present invention is characterized in that an intermediate shaft is provided in parallel, and the driving force of the input shaft is transmitted to the second and third rotating shafts, respectively, via the intermediate shaft.

Hereinafter, one embodiment of the present invention will be described in detail based on all the drawings.

FIG. 4 is a sectional view of an embodiment of the robot wrist device of the present invention.

Inside the tip of the robot's arm 10 is a ml input shaft 11 that has a concentric triple structure. Second input shaft 12, third input shaft 1
The three inputs 14II of No. 3 are attached via bearings so as to be rotatable relative to each other, and the first input shaft 11 is disposed at the outermost periphery.

The first rotating shaft 14 has a cylindrical shape and is integrated with the first input shaft 11, and is used for simultaneous movement with the three input shafts 11, 12 and 13.
The machine is designed to rotate.

Next, the second rotating shaft 15 is perpendicular to the first rotating shaft 14, passes through the first rotating shaft 14, and is attached via a bearing. Also,
An intermediate shaft 16 parallel to the second rotation shaft 15 is installed on the first rotation shaft 14 on the proximal side of the second rotation shaft 15 via a bearing. Then, for driving the first rotating shaft 14, a second
A bevel gear 17 is integrally attached to the tip of the input shaft 12,
The bevel gear 18 that meshes with the bevel gear 17 is the intermediate shaft 16.
It is rotatably attached to one end via a bearing. Further, the spur gear 1 is integrally formed with the bevel gear 18 on the intermediate shaft 16.
9 is attached, and a spur gear 20 that meshes with the flat wheel 19 is fitted on one end of the second rotating shaft 15, so that the driving force of the human-powered shaft 12 is perpendicular to the first rotating shaft 14. It is intended to be transmitted to A cylindrical support frame 21 is attached to the second rotating shaft 15 and is perpendicular to the axis thereof, and is located on the inner circumference of the first rotating shaft 14 .

Furthermore, the third [! 1li1 rotation axis 22 is the second rotation 1i11
15, and is rotatably supported on the inner periphery of the support frame 21 via a bearing, and a radial mounting flange 23 is fitted to the tip thereof. In order to drive this third rotating shaft 22, a bevel gear 24 is provided at the tip of the third input shaft 13.
A bevel gear 25 meshing with the bevel gear 24 is fitted onto the other end of the intermediate shaft 16, and a spur gear 26 is integrally attached to the bevel gear 25. A spur gear 27 that meshes with this spur gear 26 is rotatably supported by a bearing on the other end of the second rotating shaft 15, and an umbrella wheel 28 is attached integrally with this spur gear 27, and the third rotating shaft 15 rotates. Axis 2
The driving force of the third input shaft 13 is transmitted by meshing with an umbrella wheel 29 fitted to the base end of the third input shaft 13.

These first rotating shafts 14. Second rotating shaft 15. Third rotation axis 2
The axes of 22 intersect at one point O.

In addition, a cover 30 is attached to the first rotating shaft 14 so as to cover the intermediate portion between the robot 10 and the hand attachment flange 23.

In the robot wrist device configured as described above, the rotation of the first input shaft 11 is controlled by a drive control mechanism (not shown), so that the first rotary shaft 14, which is integrated with the first input shaft 11, is rotated coaxially with the first input shaft 11 and rotates around the entire wrist. The rotation of the second input shaft 12 is controlled by a drive control mechanism (not shown) to rotate the first rotation shaft 1.
4, the support frame 21 is rotated by a second rotation m15 orthogonal to the second rotation m15. Further, by controlling the rotation of the third input shaft 13 by a drive control mechanism (not shown), the third rotating shaft 22 perpendicular to the second rotation l1II15 is rotated, and the hand attachment flange 23 is rotated.

Therefore, by combining the rotational movements of these three rotational axes 14.15°22, the hand mounting flange 23 can be rotated 11114.15.22 to form an arbitrary spherical shape centered on the point O. can be oriented in the direction of

Moreover, # is located on the first rotating shaft 14 and the third rotating shaft 22.
: Due to its structure, it is possible to freely rotate many times in any direction without being subject to restrictions such as drying of each part. On the second rotating shaft 15, the engagement center point of the driving umbrella wheel 17, 18 and the driving umbrella wheel 28 of the third rotating shaft 22.
．． 29 is misaligned with the engagement center point, and the center point of the bevel wheel 24.25 has a loose fit, and the center point of the bevel wheel 28.29 is misaligned.
Since the meshing center point of
By rotating the umbrella wheel 5, mechanical interference between the umbrella wheel 29, the umbrella wheel 17, and the umbrella wheel 24 can be avoided, and the operating range can be widened.

Further, since the axes of the first to third rotating shafts 14, 15, and 22 are perpendicular to each other, each rotating shaft can be operated based on orthogonal coordinates, making the operation easy and the control system simple.

In the above embodiment, a bevel wheel and a spur gear are used as a transmission system for driving force from each input shaft to each rotating shaft. It is also possible to use a system. Further, this wrist device can also be used as a positioning device for industrial robots and other devices.

As specifically explained above in conjunction with the embodiments, according to the present invention, an intermediate shaft is installed parallel to the second rotating shaft, and the second rotating shaft and the third rotating shaft are respectively driven via this intermediate shaft. So the 411IIIil of the three rotation axes is 1
Even if the wrist device rotates on three axes that intersect at a point, the structure can be simplified and the size can be reduced. In addition, interference between various parts can be avoided and the operating range can be widened.

[Brief explanation of the drawing]

1 to 3 are schematic configuration diagrams of conventional robot wrist devices, respectively, and FIG. 4 is a longitudinal sectional view of an embodiment of the robot wrist device of the present invention. In the drawing, lO is the arm of the robot, 11 is the first input axis, 12I/'i is the second human power axis, 13 is the third human power axis, 14 is the first rotation axis, 15 is the second rotation axis, 16 is An intermediate shaft, 214'j support frame, 22 a third rotating shaft, and 23 a hand mounting flange. . % Applicant Mitsubishi Heavy Industries, Ltd. Sub-Agent Patent Attorney Shibu Hikari Ishi (and 1 other person)

Claims (1)

[Claims] The first one rotates about the concentric input shaft l1811 which is driven respectively through three concentrically arranged input shafts.
It has a rotation axis, a second rotation axis perpendicular to the second rotation axis, and a third rotation axis perpendicular to the second rotation axis, and is arranged so that the @ lines of these three rotation axes intersect at one point. In the robot wrist device, an intermediate axis is provided parallel to the second rotation axis,
A wrist device for a robot, characterized in that the driving force of the input shaft is transmitted to the second and third rotating shafts via the intermediate shaft.