JPS62241685A - Hand 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 hand for an industrial robot that attaches and detaches a workpiece to and from a machine tool such as an NC lathe.

2. Description of the Related Art As a conventional robot hand of this type, for example, the one shown in FIG. 3 is known. In the figure, reference numeral 20 denotes a robot arm, in which a control rotation means (not shown), such as a DC servo motor, is housed in its tip, and its rotational drive shaft projects downward as a downward wrist shaft 21. The wrist 22 is attached to.

The wrist 22 is equipped with a controlled rotation means (such as a DC servo motor).
(not shown) is housed, and its rotary drive shaft projects forward as a forward wrist shaft 23, and a hand 24 for holding two workpieces is attached to the distal end.

Two sets of gripping claws 25A, 25 [1
has been established.

Therefore, for example, an unprocessed workpiece placed in a vertical position on a barlet having a horizontal surface is carried into the chuck 27 of the NCJM'li having a horizontal axis, and a processed workpiece held in a horizontal position by the chuck is transferred. The procedure for unloading the pallet onto a horizontal surface is as follows.

■ Grip the unprocessed workpiece W1 with the gripping claws 25B (4th a)
figure).

■Turn the forward wrist shaft 23 90 degrees to make the unprocessed workpiece W8
is held horizontally, and the processed workpiece W2 is gripped by the gripping claws 25A (Fig. 4b).

■Turn the forward wrist shaft 23 by 180 degrees to remove both workpieces W1,
Reverse the position of W2 (Figure 4C).

■ Load the unprocessed workpiece W into the chuck 27 of the NC lathe m26, and grip the unprocessed workpiece W with the chuck 27 (
Figure 4d).

(2) Rotate the forward wrist shaft 23 by 90 degrees in the opposite direction to (2) and place the processed workpiece W2 in a vertical position on the horizontal surface of the barre throat 28 (Fig. 4e).

Suppose that 11 is to enter η. In the conventional robot hand mentioned above, since it is necessary to control and rotate the forward wrist shaft 23 at a plurality of rotation angles and directions, a controlled rotation means such as a DC servo motor is used as a rotational drive source for the forward wrist shaft 23. is stored on the wrist 22.

Since the control rotation means such as a DC servo motor is heavy, the supporting rigidity of the robot arm 20 and the like must be increased, which increases the size of the robot device. Moreover, since the control rotation means is expensive, it increases the cost of the robot device.

In addition, the gripping claws 25A, 2 of the hand 24 holding two workpieces
5B are provided so as to protrude outward from the mutually opposing sides of the two-workpiece holding hand 24, so that the NC lathe 2
The external dimensions when the workpieces W, , W are held in the position of being attached to and removed from the chuck 27 of 6 (Figs. 3 and 4b)
(see figure) is large. Therefore, it is often impossible to use it for attaching and detaching workpieces to and from small-sized NC lathes.

Furthermore, from the start to the completion of attachment and detachment of the workpieces W, W2, the hand 24 holding two workpieces, that is, the forward wrist shaft 23, is rotated by a total of 3 degrees at rotation angles of 90 degrees, 180 degrees, and reverse 90 degrees. As a result, the cycle time becomes long and the operability becomes poor.

The present invention was developed in view of the background of the prior art, and aims to reduce the weight and the external dimensions of the hand holding two workpieces, significantly shorten the cycle time, and improve workability. The present invention also aims to provide a robot hand that achieves cost reduction.

The robot hand according to the present invention for carrying out "n' The two-workpiece holding hand has two sets of gripping claws, and the axis of the rotating shaft is set on an extension of a straight line that bisects the intersection angle of the two central axes.

In the present invention, by rotating the hand holding two workpieces together with the rotating shaft once at a rotation angle of 90 degrees in either the forward or reverse direction, the workpieces can be held in a position for attaching and detaching the workpieces.

Fig. 1 is a schematic side view showing one embodiment of the present invention.
A control rotation means 2 such as a C servo motor is housed, and its rotary drive shaft projects downward as a downward wrist shaft 3, and a wrist 4 is attached so as to be rotatable at the same time.

A rotating means 5 consisting of a rotary actuator is housed in the wrist 4, and its rotating shaft 6 projects obliquely downward.
A hand 7 holding two works is attached to the tip so as to be rotatable at the same time. The center axis C of the hand 7 holding the two workpieces
Two sets of gripping claws 8A and 8B are arranged such that 1 and C2 intersect at right angles. That is, one gripping claw 8A is provided to protrude laterally from the vertical side surface 7a of the hand 7 holding two workpieces, and the other gripping claw 8B is provided on the horizontal lower surface 7b of the hand 7 holding the two workpieces.
It protrudes downward from the The axis of the rotating shaft 6 is set on an extension of a straight line C3 that bisects the intersection angle θ of the central axes C1 and C2 of the two sets of gripping claws 8A and 8B.

Next, the operation of the above configuration will be explained.

■ Grip the unprocessed workpiece W placed vertically on the horizontal surface of the pallet l-P with one gripping claw 8B (second
Figure a).

■The gripping jaws 8^ grip the machined workpiece W2, which has been gripped in a horizontal position by the chuck 9^ of the NC lathe 9, for example.
Figure 2b).

■ Drive the rotating means 5 to rotate the rotating shaft 6 and the hand 7 holding the two workpieces by 180 degrees in either the forward or reverse direction, and move the positions of the workpieces W, , W2 as shown in Fig. 2C. Replace. That is, the unprocessed workpiece W1 is held in a horizontal position, and the processed workpiece W2 is held in a vertical position.

■ Place the unprocessed workpiece Wl on the chuck 9A of the NC lathe 9, and grip the unprocessed workpiece W with the chuck 9A (
Figure 2d).

■ Place the processed workpiece W2 in a vertical position on the horizontal surface of the pallet P (Fig. 2e).

In this way, the rotating shaft 6 and the hand 7 holding two workpieces are
By rotating the axis 80 degrees, two sets of workpiece gripping claws 88, 8
Since the position of B is configured to be reversed, the rotary actuator can serve as the rotation drive source for the rotating shaft 6 and the hand 7 holding two workpieces.

In addition, since the central axes C1 and C2 of the two sets of gripping claws 8A and 8B are arranged to intersect at right angles, the outer dimension L2 (see FIGS. 1 and 2c) is different from the conventional outer dimension. is significantly reduced in comparison.

Furthermore, the cycle time can be shortened since the two-workpiece holding hand 7, that is, the rotating shaft 6, is rotated only once during the period from the start to the end of the attachment and detachment of the works W, , W2.

As described above, according to the present invention, two sets of gripping claws are arranged on the hand holding two workpieces attached to the rotating shaft of the rotating means so that the central axis intersects at right angles. However, since the axis of the rotating shaft is set on the extension of the straight line that bisects the intersection angle of the central axis, the positions of the two sets of gripping claws can be reversed just by rotating the rotating shaft once 180 degrees. Therefore, a lightweight rotary actuator can be used instead of a DC servo motor as the rotation means, and the weight and cost of the robot device can be reduced.

In addition, since the external dimensions are reduced as mentioned above, small N
Workpieces can be attached to and removed from the C lathe, expanding the range of use.

Furthermore, since the hand holding two workpieces only needs to be rotated once from the start to the completion of attachment/detachment of the workpieces, cycle time can be shortened and work efficiency can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an embodiment of the present invention, FIGS. 2a to 2e are schematic explanatory views showing the operation order, FIG. 3 is a schematic side view of a conventional example, and FIGS. 4a to 4e. FIG. 2 is a schematic explanatory front view showing the order of operations. 5... Rotating means, 6... Rotating shaft, 7... Work 2
Individual hands, 8A, 8B...2 sets of gripping claws, C,...
C2...Central axis line, C2...Straight line. Figure 1 (a) (b) Figure 2 (Zone 1) (C) Figure 2 (Part 2) Figure 3 (a) (b) Figure 4 (fol)

Claims (2)

[Claims] (1) A two-workpiece holding band attached to the rotating shaft of the rotating means and rotating simultaneously with the rotating shaft;
A robot hand comprising a pair of gripping claws, wherein the axis of the rotating shaft is set on an extension of a straight line bisecting each intersection of the two central axes. (2) The robot hand according to claim 1, wherein the rotating means is a rotary actuator.