JP2542078B2 - Industrial robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an industrial robot equipped with a gravity compensation mechanism,
In particular, the present invention relates to an improvement of a vibration preventing structure of a roller chain reversing portion of a gravity compensation mechanism.

[Conventional technology]

FIGS. 4 to 6 show a conventional industrial robot in which a gravity compensation mechanism is incorporated into the industrial robot disclosed in, for example, Japanese Patent Laid-Open No. 63-278776. ) Is a boom of a robot which moves up and down by driving a ball screw (3) incorporated in the robot body (4), (4) is a counter weight arranged in the robot body (2), (5)
Is a guide rail for guiding the lifting and lowering of the counterweight (4), (6) is a sprocket rotatably arranged on the upper part of the robot body (2), and (7) is a guide attached to the counterweight (4). A guide shoe slidingly contacting the rail (5), (8) a bracket to which the sprocket (6) is attached, (9) a fixing bolt for fixing the bracket (8) to the robot body (2), (11) ) Is a roller chain that connects the boom (1) and the counterweight (4), and an intermediate portion is wound around the sprocket (6). Reference numeral (12) is a cover for covering the reversal portion composed of the sprocket (6).

The conventional industrial robot is configured as described above, and since the boom (1) is connected to the counterweight (4) having almost the same weight as the boom via the roller chain (11), its gravity is compensated. It

[Problems to be Solved by the Invention]

In the conventional industrial robot as described above, since the sprocket (6) is used in the reversing part of the roller chain (11), if the roller chain (11) wears and grows over the years, the roller chain (11) may become worn. There is a problem that the meshing condition between the (11) and the sprocket (6) deteriorates and vibration occurs. In this case, large maintenance such as replacement of the roller chain (11) is required, and there is a problem that maintenance cost increases.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain an industrial robot that generates less vibration and noise even if wear and elongation of the roller chain occurs due to long-term use.

[Means for solving the problem]

The industrial robot according to the present invention is an industrial robot in which a vertical movement unit and a counterweight of the robot are connected to each other via a roller chain wound around the reversing unit to form a gravity compensation mechanism. A chain roller guide made of synthetic resin having excellent wear resistance and self-lubricating property is detachably attached.

[Action]

In the present invention, the roller chain is turned over along the chain roller guide. Since this roller chain roller guide is made of synthetic resin having excellent wear resistance and self-lubricating property, the contact R with the roller chain can be increased without taking up space, thereby lowering the hardness and vibrating, Noise can be reduced. Further, even if the wear is severe under bad conditions such as dust and sand, the chain roller guide can be detached and replaced, so that the chain roller guide can be easily replaced.

〔Example〕

1 and 2 show an embodiment of the present invention, in which the same reference numerals as those in FIGS. 4 to 6 designate the same or corresponding parts. (10) is a chain roller guide attached to the reversing portion, which is made of a synthetic resin having excellent wear resistance and self-lubricating property, such as ultra-high-molecular polyethylene or 6.6 nylon. The chain roller guide (10) has a shape obtained by dividing an elliptical plate into two along the major axis. The chain roller guide (10) is attached to the bracket (8) and the fixing bolt (9) is attached. By removing
The bracket (8) can be attached / detached and replaced integrally.

In the industrial robot configured as described above, the roller chain (11) is in sliding contact with the outer peripheral surface of the chain roller guide (10), and the chain roller guide (10)
Flip along. At this time, the chain roller guide (1
Since 0) is formed of synthetic resin having excellent wear resistance and self-lubricating property, the contact R with the roller chain (11) can be increased without taking up a space. Therefore, the hardness of the chain roller guide (10) can be reduced, and vibration and noise can be reduced.

Further, since the chain roller guide (10) can be easily replaced by removing the fixing bolt (9), there is no problem even when used under bad conditions such as dust and sand.

FIG. 3 shows another embodiment of the present invention, in which the chain roller guide (10) is attached to the outer peripheral portion of a bracket (8) having a shape obtained by dividing an elliptical plate into two along the major axis. It is formed in such a gate shape and is detachably attached to the bracket (8) via the fixing bolt (9).

With this structure, the amount of material used for the chain roller guide (10) can be reduced, and the chain roller guide (10) can be stably supported even when the hardness of the chain roller guide (10) is low. .

〔The invention's effect〕

As described above, according to the present invention, a chain roller guide formed of synthetic resin having excellent wear resistance and self-lubricating property is detachably attached to the reversing portion of the roller chain, and the roller chain is Since it guides, even if the roller chain wears and stretches due to long-term use, vibration and noise are less likely to occur, and it is easy to replace the chain roller guide when worn. . Moreover, since the chain roller guide having self-lubricating property is used, there is little vibration and noise, the up-and-down moving part can be moved at high acceleration and high speed, and the number of operations per unit time is large,
There is also an effect that a highly efficient industrial robot can be provided. Furthermore, no lubricant is required, and even if the vertical moving part is moved at high acceleration and high speed, the lubricant does not scatter around, so a clean atmosphere can be maintained, for example in a clean food field. There is also an effect that an industrial robot used in the environment can be provided. Furthermore, since the chain roller guide can be easily replaced, the replacement can be completed in a short time, work interruption can be shortened, and an industrial robot having a high operating rate can be provided.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an industrial robot showing an embodiment of the present invention, FIG. 2 is an enlarged view of its reversing portion, and FIG. 3 is a view corresponding to FIG. 2 showing another embodiment of the present invention. FIG. 4 is an overall configuration diagram showing a conventional industrial robot, FIG. 5 is a left side view of FIG. 4, which is equivalent to FIG. 1, and FIG. 6 is an enlarged view of the reversing unit of FIG. (1) …… Boom, (2) …… Robot body, (4) …… Counter weight, (8) …… Bracket, (9) …… Fixing bolt, (10) …… Chain roller guide, (11) ) …… Roller chain. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. An industrial robot having a gravity compensating mechanism in which a vertically moving part of a robot and a counterweight are connected to each other via a roller chain wound around a reversing part, wherein the reversing part has abrasion resistance. An industrial robot characterized in that a chain roller guide made of synthetic resin having excellent self-lubricating property is detachably attached.