JPH01310879A - Link mechanism of industrial robot - Google Patents

Abstract

PURPOSE:To reduce the lateral width dimension of a robot body by permitting a driving means for the first and second robot arms to be piled and arranged in a robot machine body in the longitudinal arrangement by shifting the supporting point of a link mechanism rearward. CONSTITUTION:A link mechanism 30 for transmitting the turning driving force of the second driving means 19 onto the second robot arm 6 is formed by sepa rating one joint of a parallel four-node link mechanism to two shifted nodes. In other words, the supporting point of the first robot arm 5 and the supporting point of a link member 31 connected with the second driving means 19 in the link mechanism 30 are installed with a deflection. Therefore, the first and second driving means 18 and 19 can be arranged inside a turning base 17, shifted in the longitudinal direction. Therefore, the width dimension W1 of the robot machine body can be reduced markedly, and the small-sized robot can be manu factured, and the generation of the interference at a site can be dissolved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a link mechanism for an industrial robot, and in particular, the present invention relates to a link mechanism for an industrial robot, and in particular, to reduce the width of the body structure of an industrial robot so that it can be easily connected to other robot bodies and surrounding equipment. The present invention relates to a link mechanism for an industrial robot that can prevent the occurrence of interference.

[Conventional technology]

Industrial robots, especially articulated robots, include a first robot arm (W-axis arm) that can swing back and forth using one end as a fulcrum on the rotating body of the robot body, and a pivot point at the top of the first robot arm. The structure includes a second robot arm that is attached to the robot arm and is swingable, and an end effector is provided at the tip of the second robot arm so as to have multiple degrees of freedom of movement.
It is widely used in welding robots, painting robots, etc.

This type of articulated Lojosoto is shown in Figure 3 as an example.
The robot arm 5 swings and turns with its lower end as the fulcrum F (W
At the upper end of the first robot arm 7, one place 6a of the rear end portion of the second robot arm 6 is attached to the swivel base 7 so as to be able to swing (swivel around the U axis). The first and second robot arms 5.6 are pivoted and connected to each other.
The drive source for rotating around the axis and the U-axis includes first and second drive means 8.9 each consisting of a drive motor and a speed reducer, located on both sides of the lower end fulcrum of the first robot arm 5. By being attached in a laterally protruding structure from the swivel table 7, one first drive means 8 directly drives the first robot arm 7, and the other second drive means 9 generally drives the first robot arm 7. The second robot arm 6 is driven via a parallel four-bar linkage mechanism 10 provided at the rear of the robot arm 5. That is, the parallel four-bar linkage mechanism 10 includes a link member 11 extending rearward from the fulcrum F of the first robot arm 5, one end 12a of which is pivotally connected to the link member 11, It has a link member 12 pivotally connected to the rearmost end 6b of the arm 6, and has the above-mentioned pivot point 6a, fulcrum F, t.
The lX landing points 12a and 6b form four nodes. When this is viewed from arrows ■--■ in FIG. 3, it becomes the parallel four-bar link mechanism 10 schematically illustrated in FIG. 4. In this case, conventionally, a first driving means 8 for driving the first robot arm 5 is used.
Since the link mechanism 10 is a parallel four-bar link mechanism, the second driving means for driving the second robot arm 6 via the link mechanism 10 is always arranged coaxially on the axis passing through the fulcrum F. It has a similar configuration.

[Problems to be solved by the invention]

As described above, each driving means for driving the first and second robot arms of the articulated robot is a robot body, that is,
If the structure protrudes from both sides of the swivel table, the width W of the robot body. (See Figure 3). Therefore, many industrial robots of this type are installed side by side at robot work sites, etc.
When the robot is used or when various types of equipment that cooperate with the industrial robot are placed around it, it is inevitable that the drive means provided with the protruding structure described in 1. Since it is necessary to secure the installation area of the robot with enough margin to enable it to turn without causing interference with the robot, there is a problem that ultimately the equipment cost increases. Therefore, the present invention provides a structure for Roboso I- that solves these problems, and particularly provides an improved structure for the link mechanism.

[Means of solution and action]

That is, according to the present invention, a first robot movable part that is movable with one end as a fulcrum; a second robot movable part that is movable with a fulcrum at the other end of the first robot movable part; The tenth pot is horizontally installed and connected to one end of the movable part, and the first
a first driving means for driving the movable part of the robot; a link mechanism having a fulcrum at a position shifted rearward from one end of the first movable part of the robot; There is provided a link mechanism for an industrial robot, comprising: a drive means and a second drive means provided in a front-back arrangement and driving the second moving part via the link mechanism; According to such a configuration, since the fulcrum of the link mechanism is configured to be shifted rearward, the first and second drive means are also configured to be shifted in position in the front and back arrangement, unlike in the case of a coaxial arrangement. , it is possible to eliminate the lateral protruding structure and to integrate and arrange it in the center of the robot body, thereby reducing the width of the robot body. Hereinafter, the present invention will be explained in more detail based on Examples.

〔Example〕

FIG. 1 shows an example of an industrial articulated robot equipped with a link mechanism according to the present invention, and FIG. 2 shows the configuration of the link mechanism according to the present invention in comparison with FIG. FIG.

Referring to FIG. 1, the first and second robot arms 5.6 of the industrial articulated robot are constructed in the same manner as the articulated robot shown in FIG. The pivot joint 17, to which the lower end is pivoted and attached, has first and second drive means 18 for swinging and pivoting the first and second robot arm 5.6 about the W axis and the U axis. It has a structure in which approximately .19 is built-in. In this case, the link mechanism 30 that transmits the turning driving force of the second drive means 19 to the second robot I/arm 6 is a parallel four-bar link mechanism as shown in the schematic diagram of the mechanism in FIG. One node is separated and shifted into two nodes to create a separate structure. That is, the fulcrum F1 of the first robot arm 5 and the fulcrum F of the link member 31 connected to the second driving means 19 in the link mechanism 30.
2 and 2 are set apart from each other by a distance f, so
The necessity of arranging the first and second drive means 18, 19 on the same axis is no longer necessary, but they are arranged offset back and forth. It is now possible. For this reason, it is possible to provide both drive means 18, 19 inside the swivel base 17 in a front-back arrangement, and moreover, to arrange them together in the center of the swivel base 17. As a result, as is obvious from FIG.
) Width dimension W of body a. This allows for even greater reductions.

According to the present invention, the link mechanism 30 is different from the parallel four-bar link mechanism 10 used in the conventional multi-joint Robosol l-, in that the two nodes F and F2 are separated and staggered. . According to the conventional parallel four-bar link 10, the second
When receiving the turning driving force from the driving means 9, the link member 11 and the second robot arm 6 always operate while maintaining a parallelogram, so the operating angles are equal. According to the link mechanism 30, the length dimension of the link member 31 and the distance τJ between the two rear pivot points 6a and 6b of the second robot arm 6 can be formed to be different from each other in FIG. As a result, by appropriately selecting the ratio of the drawing method, it is possible to configure the second robot arm 6 so that the operating angle is larger than the operating angle of the link member 31. Therefore, Although the link mechanism 30 itself is configured on a small scale, the operating angle of the robot arm can be increased, and it is also possible to secure a large operating area with a compact robot body.

〔Effect of the invention〕

As can be understood through the description of the embodiments above, according to the present invention, the structure of the link mechanism provided at the joint part of an industrial robot is obtained by separating one node from the conventional parallel four-bar link mechanism. For this purpose, the driving means for driving the first and second robot arms, which are the first and second movable parts of the robot, are arranged coaxially (inside the robot body in a front-back arrangement). Since they can be stacked and arranged, it has become possible to reduce the width of the robot body.In other words, it has promoted compactness, and as a result, it has been possible to eliminate inconveniences such as interference at robot work sites. This not only prevents damage to the robot due to interference, but also contributes to improving safety.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of an industrial articulated robot equipped with a link mechanism according to the present invention, FIG. 2 is a schematic mechanical diagram showing the configuration of the link mechanism according to the present invention, and FIG. The figure is a perspective view showing the configuration of a conventional industrial robot, and Figure 4 is the same.
FIG. 2 is a schematic diagram of a conventional parallel four-bar linkage mechanism. 5... First robot arm, 6... Second robot arm, 6a, 6b... Pivot point, 17... Swivel base, 30...
... Link mechanism, 31.32... Link member, F+, F2... Fulcrum, W,... Width dimension of robot body.

Claims (1)

[Claims] 1. A first robot movable part movable with one end as a fulcrum;
a second robot movable part that has a fulcrum at the other end of the first robot movable part and is movable; and a second robot movable part that is horizontally installed and connected to one end of the first robot movable part to drive the first robot movable part. and a link mechanism having a fulcrum at a position rearwardly shifted from one end of the first robot movable part, the link mechanism being horizontally installed and connected to the fulcrum, and arranged front and rear with the first driving means. and the second link via the link mechanism.
A link mechanism for an industrial robot, comprising: a second driving means for driving a movable part of the robot. 2. The link mechanism is formed as a four-bar link mechanism having first to fourth nodes driven by the second driving means, the first node forming a fulcrum of the link mechanism,
The link mechanism for an industrial robot according to claim 1, wherein the second robot movable part and the link mechanism are coupled by the fourth node.