JPS62199377A - Tool attitude holder for industrial 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 Field of the Invention The present invention relates to a tool posture holding device for a highly versatile industrial robot used for inserting, extracting, assembling, etc. parts in high-mix, low-volume production.

Prior art Recently, this type of versatile industrial robot has been attracting attention, but in particular, when multiple work stations are set up around one robot, the ground contact area of the robot is Since it is necessary to have a small robot with a wide working area, many articulated robots I~, which have a plurality of horizontally pivotable arms, are in use.

This articulated robot 1 has a first
It has a first arm 4 that rotates around a support 3 in response to rotation of a motor 9, and a rotating shaft 12 that rotates in response to rotation of a second motor 11 is disposed at the tip of this first arm 4. There is. A second arm 13 is fixed to the lower end of this rotary shaft 12 and configured to rotate together with the second arm 13, and a tool shaft 16 holding a tool 32 is held at the tip thereof so as to be movable up and down and rotatable. ing. Further, the articulated robot 1 has a tool posture holding device below the first arm 4 and the second arm 13. This tool posture holding device has a first sprocket 27a fixedly located around the support column 3 and below the first arm 4.

Further, a plurality of rows of second sprocket parts 28 are rotatably arranged under the rotating shaft 12 at the tip of the first arm 4, and a first sprocket part 28 is disposed between the first sprocket l-27a and
A chain 29 is wound. Further, a third sprocket 30 that rotates together with the tool shaft 16 at the tip of the second arm 13 is fixed to the tool shaft 16, and a second chain 31 is wound between it and the second sprocket portion 28. There is.

Problems to be Solved by the Invention In this tool posture holding device, even if the first arm 4 and the second arm 13 turn and the direction of the rotating shaft 12 changes, the first sprocket 27a and the second sprocket portion 28 do not move. The second sprocket portion 28 maintains a constant posture with respect to the first arm 4 by the wound first chain 29.

Therefore, the second chain 31 wound between the second sprocket part 28 and the third sprocket 30 does not rotate at all even if the second arm 13 rotates and the direction of the second arm 13 changes. The shaft 16 and the tool 32 fixed thereto can also maintain a constant posture. However, even if the first sprocket 27a is fixed to the support column 3, as the first arm 4 rotates, the engagement position of the first chain 29 with the first sprocket 27a changes sequentially. If the first sprocket 27a and the first chain 29 are exposed, the worker's hands, clothes, etc. will get caught between the first sprocket 27a and the first chain 29, which is not only extremely dangerous, but also dangerous. A cover 33 or the like is required to prevent foreign objects from getting caught between the first sprocket 27a and the first chain 29, and the robot 1
There are disadvantages such as an increase in the cost of ~.

Means for Solving the Problems The present invention aims to eliminate the above-mentioned drawbacks, and includes a first arm that rotates about a column in response to rotation of a first motor. Further, a rotating shaft that rotates in response to rotation of the second motor is disposed at one end of the first arm, and the second arm is fixed to one end of the rotating shaft so as to rotate together with the rotating shaft.

A tool shaft having a tool is rotatably held at the tip of the second arm, and the tool is configured to move to a predetermined position in response to rotation of each motor.

A first sprocket located within a first arm is fixed to the column. Further, a rotatable second sprocket part is arranged around the rotation axis at the tip of the first arm, and the second sprocket part has a sprocket located in the first arm and a sprocket located in the second arm. Sprockets 1 to 1 are provided. Roughly speaking, the tool shaft has a third arm rotatable integrally with the tool shaft and located within the second arm.
A sprocket is attached, and the sprockets 1 to 1 in each arm are wound by a chain located in the respective arm.

Effect: In the industrial robot, even if the first arm and the second arm turn, the first sprocket is fixed to the column, so the first chain does not rotate. Therefore, although the direction of the rotation axis changes as the first arm turns, the second sprocket portion does not rotate and the attitude of the second sprocket portion does not change. Therefore, the second chain and the third sprocket also maintain a constant attitude, and the tool shaft and the tool fixed thereto are held in the attitude before the first arm and the second arm rotate. Moreover, since the first sprocket and the first chain are housed within the first arm,
The operator's hands, clothes, etc. will not be caught between the first sprocket and the first chain.

Further, since the sprocket and chain are housed within the first arm and the second arm, it is possible to completely prevent foreign objects from getting caught between the sprocket and the chain.

EXAMPLE Hereinafter, an example will be described based on the drawings. In FIG. 1, reference numeral 1 is an articulated industrial robot, which has a column 3 fixed to a cylindrical base 2. As shown in FIG.

At the top of this support 3 is a first arm 4 that is aligned with its axis.
The first arm 4 has a horizontal cylindrical part 4a extending in the horizontal direction and cylindrical parts 4b extending in the vertical direction at both ends thereof.
It consists of Further, the horizontal cylindrical portion 4a of the first arm 4 has a partition wall 4C so as to connect the cylindrical portions 4b at both ends, and the space above the partition wall 4C is a part for storing various wirings, and the space above the partition wall 4C will be described later. It is configured to accommodate the first chain 29.

The base of the first arm 4 is inserted through the support column 3 so as to cover it, but a cross roller is provided between the lower part of the first arm 4 and the bearing stand 6 fixed to the mounting portion 3a of the support column 3. A bearing 7 is arranged so that the first arm 4 can pivot around the column 3. Further, an output shaft of a CYCLO reduction gear (trade name) 8 is fixed to the upper end of the support column 3, and a CYCLO reduction gear 8 fixed to the input shaft of the CYCRO reduction gear 8 is fixed to the upper end of the first arm 4. The drive shaft of the first motor 9 is fixed, and the rotation of the first motor 9 is decelerated and transmitted to the first arm 4. Furthermore, a pulse encoder 10 is provided at the upper end of the first motor 9.
is fixed, and the rotation angle of the first motor 9 is configured to be detected.

A second motor 11 is fixed to the upper part of the cylindrical portion 4b at the tip of the first arm 4, and the input shaft of the Zycro speed reducer 18a is connected to the drive shaft of the second motor 11. A rotating shaft 12 is connected to the output shaft of the cyclo reducer 8a, and an @2 arm 13 is fixed to the lower end of the rotating shaft 12.

Further, a cross roller bearing 7a is disposed between the second arm 13 and the first arm 4 via a bearing stand 6a fixed to the bearing case 14, and a cross roller bearing 7a is disposed between the second arm 13 and the first arm 4.
When the second arm 13 rotates in response to the rotation of the second motor 11, the second arm 13 is configured to pivot at the tip of the first arm 4.

The second arm 13 is formed in substantially the same shape as the first arm 4, and a bearing sleeve 15 is rotatably held in a cylindrical portion at the tip thereof. A tool shaft 16 that is integrally rotatable and vertically movable is disposed on this bearing sleeve 15, and a coupling tool 19 that can be raised and lowered integrally with a nut portion 18b, which will be described later, is fixed to the upper end of this tool shaft 16. ing. Further, the tool shaft 1 is provided at the tip of the second arm 13.
A screw shaft 18a extending parallel to the second arm 13 is rotatably arranged at that position, and when it rotates under the rotation of a third motor 20 horizontally fixed in the upper space of the second arm 13, the nut portion is rotated. 18b is configured to move up and down along the screw shirt t-18a.

A sleeve 21, which forms part of the tool posture holding device, is fixed around the support column 3 by a spun ring 22, and a first sprocket portion 28 is fixed to the sleeve 21. Further, the first sprocket portion 27 is arranged so as to press the span ring 22 with its lower end, and is configured to be firmly fixed to the support column 3. Moreover, the first sprocket part 27 has a first sprocket 27a located inside the cylindrical part 4b of the first arm 4, and there is a first sprocket 27a between the first sprocket 27a and a second sprocket t-28a to be described later. A horizontally extending first chain 29 is wound within the arm 4.

A second sprocket portion 28 is arranged around the rotating shaft 12 so as to be rotated while being sandwiched between the bearing stand 6a and the bearing case 14. The second sprocket portion 28 includes a second sprocket 28a that is rotatable within the first arm 4 and a second sprocket 28b that is rotatable within the second arm 13.
The first chain 29 is wound around the upper second sprocket 2&a. Also, the second
A second chain 31 extending horizontally within the second arm 13 is wound between the sprocket 28b and a third sprocket 30 fixed to the bearing sleeve 15. Moreover, the second chain 31 is arranged so as to pass six times through the upper space of the second arm 13, and is configured to be separated from the third motor 20 arranged in the upper space.

In the above industrial robot, the first T: part 9 and the second
When the motor 11 is driven, the 17th arm 4 turns around the support 3 at a predetermined angle, and the second arm 13 rotates around the first arm 4.
The tip of the arm 4 rotates at a predetermined angle. Therefore, the second
The tool 32 fixed to the tool shaft 16 at the tip of the arm 13 reaches above a predetermined position.

Thereafter, when the third motor 20 is driven and the screw shaft 18a rotates, the tool fIIl 116 is lowered to a predetermined position as the nut portion 18b is raised and lowered, and the tool shaft 1
A tool 32 integral with 6 can reach a predetermined position.

At this time, even if the first arm 4 and the second arm 13 turn, the first chain 29Ij3 and the second sprocket part 28 do not rotate because the first sprocket 27a is fixed to the support column 3. Therefore, the rotating shaft 12 changes its direction due to the rotation of the first arm 4, and the second sprocket 1-28b does not change its direction, but maintains its posture constant. Therefore, the second link 31 and the third link
The sprocket 30 also includes the first arm 4a3 and the second arm 1.
3, the tool shaft 16 can maintain its attitude and maintain a constant attitude. Furthermore, the engagement position of the first chain 29 with the first sprocket 27a changes as the first arm 4 rotates, but since this engagement part is completely within the first arm 4, the operator can Do not bite hands, clothing, etc.

As described in detail, the present invention has a structure in which all the mechanisms for maintaining a constant posture of the tool shaft, which is rotatably and movably raised and lowered at the tip of the arm, are contained within the arm. This prevents dangerous chains and sprockets from being exposed, and prevents workers' hands, clothes, etc. from being exposed when the first chain sequentially changes the engagement position with the first sprocket as the first arm rotates during robot adjustment work. Not only is it possible to provide an extremely safe robot 1~ with no pinching of the This eliminates the need for a cover to prevent foreign matter from entering the engaging portion, and has advantages such as being able to provide an inexpensive robot with fewer parts.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of the present invention, and FIG. 2 is an overall explanatory view of a conventional example. 1 industrial robot, 2 base, 3 pillar,
3a mounting part, 4 first arm,
4a horizontal cylinder part, 4b cylinder part, 4C
Partition wall, 56.6a Bearing stand, 7.7a Cross roller bearing, 8.8a, Zycro reduction gear, 9 1st motor, 10 Pulse encoder, 11 2nd motor, 12 Rotating shaft,
13 second arm, 14 bearing case,
15 bearing sleeve, 16 tool shaft,
17 18a Screenshot 1~. 18b nut 1~ part, 19
Connector, 20 Third motor, 21
Installation is with sleeve, 22 Span ring, 27
First sprocket portion, 27a first sprocket. 2
8 2nd sprocket i~ part,

Claims (1)

[Claims] The first arm 4 is arranged to rotate about the support 3 in response to the rotation of the first motor 9, and a rotating shaft 12 is arranged at one end of the first arm 4 to rotate in response to the rotation of the second motor 11. A second arm 13 is fixed to one end, and a tool shaft 16 is rotatably held at the tip of the second arm 13, and a tool 32 is held by this.
In an industrial robot configured to move a robot to a predetermined position, a first sprocket 27a located in a first arm 4 is fixed around a support 3, and A rotatable second sprocket portion 28 is disposed, and the second sprocket portion 28 is provided with a second sprocket 28a located within the first arm 4 and a second sprocket 28b located within the second arm 13. A second
A tool posture holding device characterized in that a third sprocket 30 located within an arm 13 is attached, and a chain is wound around the sprocket within each arm.