JPS5853998B2 - Industrial robot wrist drive force transmission mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a wrist driving force transmission mechanism for an industrial robot.

Figure 1 shows an example of the axis configuration of an industrial robot.
There is a pivot axis for the torso 1, on which the arm frame 2 rests, which performs an upward and downward movement.

There is an arm 3 at the end, which moves back and forth.

Furthermore, there is a wrist attached to the end.

That is, first, there is a wrist bending axis 4 for performing a bending operation,
There is a wrist rotation shaft 5 at the tip of the wrist rotation shaft 5 for rotating the wrist.

By the way, the actuator that drives the movement of the wrist is usually not provided with a thousand words to make the wrist smaller and improve workability, but is installed, for example, on the arm frame 2, and the actuator is used to drive the wrist through a drive shaft, gears, etc. Often moved.

FIG. 2 shows a conventional driving force transmission mechanism in this case.

When the rotatable bending drive shaft 11 rotates with respect to the wrist box 13 via the bearing 12 as shown, the rotational motion is transmitted to the bevel gear 15, the bevel gear 16, the shaft 1γ, and the bending shaft box 18 in this order. The box 18 is made to perform a bending motion.

Further, when the rotatable rotation 1 drive shaft 19 is rotated with respect to the wrist box 13 via a bearing 20 as shown in the figure, the rotational movement is caused by the bevel gear 21, the bevel gear 23, the shaft 24, the bevel gear 25, the bevel gear 26, etc. , the shaft 28, and the wrist tip 29 are rotated.

As shown here, the shaft 24 is rotatable with respect to the wrist box 13 via the bearing 22 and with respect to the bending box 18 via the bearing 30, and the shaft 17 is rotatable with respect to the wrist box 13 via the bearing 14. The shaft 28 is rotatable relative to the bearing 27.
It is made rotatable with respect to the bending shaft box 18 via the bending shaft box 18.

In such a configuration, it is now assumed that the bending drive shaft 11 is rotated and the rotary drive shaft 12 is fixed.

Then, since the bending shaft box 18 rotates around the shaft 17, the bevel gear 26 also rotates around the shaft 17 accordingly.

Since the mating shaft 17 and the shaft 24 are on the same straight line, the bevel gear 26
rotates around the shaft 24 while meshing with the bevel gear 25.

Here, the rotational drive shaft 19 is fixed, and the bevel gear 2
5 is also fixed, so the bevel gear 26 rotates about the shaft 28.

The movement is transmitted to the wrist tip 29 by the shaft 28, and the wrist tip 29 also rotates.

That is, when the bending drive shaft 11 is rotated, the bending shaft box 1
There is a disadvantage that not only the wrist 8 performs a bending motion, but also the wrist tip 29 causes a rotational motion.

In order to correct this, for example, when you want to perform a bending operation, you need to adjust not only the bending drive shaft 11 but also the rotation drive shaft 1
2 must also receive a correction device that rotates them at the same time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wrist drive transmission mechanism that does not have the above-mentioned drawbacks and can transmit rotational drive force without rotating the wrist tip even when the bending drive shaft is rotated.

The present invention will be explained below based on an embodiment shown in FIG.

First, regarding the bending shaft, it is the same as in the case of FIG. The bevel gear 36, shaft 37, and bending shaft box 40 are caused to perform a bending operation.

Next, instead of transmitting the rotational driving force through a planetary gear mechanism that is affected by the movement of the bending shaft as shown in FIG.
2 directly to the wrist tip 39.

That is, when the rotatable drive shaft 45 is rotated with respect to the wrist box 33 via the bearing 44, the rotational motion is transmitted to the universal joint 42, the shaft 38, and the wrist tip 39 in this order, causing the wrist tip 39 to rotate.

The shaft 37 is rotatable relative to the wrist box 33 via the shaft 34, the shaft 46 is rotatable relative to the wrist box 33 via the bearing 43, and the shaft 38 is rotatable relative to the wrist box 33 via the bearing 41. It is rotatable relative to the box 40.

Moreover, the shaft 37, the shaft 46, and the universal joint 42 are installed on the same straight line.

In this way, according to the present invention, even if the bending drive shaft 31 is rotated, the rotational driving force can be transmitted in such a manner that the wrist tip 39 does not rotate. An effective wrist driving force transmission mechanism can be provided in which the number of tongues in the structure is reduced from one to two.

[Brief explanation of drawings]

FIG. 1 is a diagram of the shaft configuration of an industrial robot, FIG. 2 is a diagram of a conventional wrist driving force transmission mechanism, and FIG. 3 is a diagram showing an embodiment of the present invention. 1... Torso, 2... Arm frame, 3...
・Arm, 4... Wrist bending axis, 5... Wrist rotation axis, 11, 31... Bending drive axis, 12, 1
4,20,22,27,32゜34.41.43,44
...Bearing, 13,33...Wrist box, 1
5,16,2L23,25,2635,36...
・・Bevel gear, 17, 24, 28, 37° 38.46・・
...Shaft, 18,40...Bending shaft box, 19.
45...Rotation drive shaft, 29, 39...
・Wrist tip, 42...Universal joint.

Claims (1)

[Claims] 1. In an industrial robot equipped with a bending axis at the wrist and a rotation axis at the tip thereof, a universal joint is provided at a portion of a rotary drive shaft that drives the rotation axis that intersects with the center line of the bending axis, An industrial robot wrist driving force transmission mechanism characterized in that a rotating shaft is driven through this universal joint.