JPH0229479B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an article transfer device that transfers articles by the rotational movement and axial movement of a rotating shaft that has an article gripping mechanism at its tip and is equipped with a rotating arm. .

Conventionally, in such article transfer devices, separate drive devices are used for the rotational movement and axial movement of the rotation axis, and the completion of the previous operation is detected and the start of the next operation is commanded. This has the disadvantage that the control circuit becomes complicated and the operating time becomes longer.

On the other hand, in the conventional method, cam grooves are formed on the outer circumferential surface and the end surface, and the rotating shaft is moved in the axial direction by the cam groove formed on the outer circumferential surface, and the turning shaft is rotated according to the change in the radial position of the cam groove formed on the end surface. Some devices are designed to rotate the shaft, thereby performing the series of operations necessary for transferring the article, but since the two cams are in separate locations and both cams perform the rotational movement, the device is difficult to operate. The disadvantage was that the whole structure became complicated and large.

In order to solve such conventional problems, the present invention uses a second cam that is rotatable concentrically on a rotation axis and a first cam that is fixed to the main body of the device, and also uses a second cam follower and a first cam follower. The purpose of this is to reduce the size of the device by attaching the two on the same axis, and to obtain a high-speed, small-sized article transfer device.

Embodiments of the invention will be described below based on the drawings.

FIG. 1 shows an embodiment in which the article transfer device according to the present invention is applied to a workpiece changing device of an NC lathe.

The article transfer device 1 is attached to a headstock 2. A chuck 3 attached to the headstock 2 holds a completed workpiece B. Further, although the explanation is omitted, a workpiece A to be processed is placed on the conveyance table 7.
Through a series of operations of the article transfer device 1, the first article gripping device 4 transfers the processed workpiece B to the conveyor table 7, and the second article gripping device 5 transfers the unprocessed workpiece A to the chuck 3.

Next, the article transfer device 1 will be explained in detail with reference to FIG.

A pivot shaft 10 is built into the bearing 9, which is fixed to the main body 8, so as to be able to move in the axial direction and rotate, and the pivot arm 6 is fixedly attached to the tip of the pivot shaft. Further, at both ends of the swing arm, a first article gripping device 4 and a second article gripping device 5 are provided.
is installed. Also, the camshaft 1 is attached to the rotation shaft 10.
4 is fixed, and a second cam follower 16 and a first cam follower 15 are incorporated therein, and each cam follower fits into the second cam groove 12a and the first cam groove 13a.

On the other hand, the second cam 12 is fixed to a second shaft 17, and its movement in the axial direction is restricted via the second shaft, and only rotational movement is possible. Further, the second cam 12 is formed with a second cam groove 12a. FIG. 3 shows a developed view of the cam groove 12a. As shown in the figure, the second cam groove 12a is formed from a corner 12b and two spiral parts 12c that extend from the corner 12b along the pivot shaft 10.

Since the first cam 13 is fixed to the device main body 8 via the bearing 9, its axial movement and rotational movement are restricted. Also, the first cam 13 has a first cam groove 1.
3a is formed. Fig. 4 shows the first cam groove 13.
A developed view of a is shown. The first cam groove 13a is the pivot shaft 1
It is formed from two straight portions 13b parallel to the axial direction of 0 and a circular arc portion 13c connecting one end of the two straight portions 13b.

Next, the operation will be explained starting with the motor 18 which is the power source. When the motor 18 rotates, the first timing pulley 20 rotates via the first shaft 19. This rotation is transmitted to the second timing pulley 22 by the timing belt 21, and the second
The timing pulley 22 rotates.

This rotation rotates the second shaft 17 via the key 11. Furthermore, the rotation of the second shaft 17 is controlled by the second cam 12.
is transmitted to.

Next, the rotation of the second cam 12 is transmitted to the pivot shaft 10. To make the explanation easier to understand, FIG. Cam groove 12a and first cam groove 1
3a, the second cam follower 16, and the first cam follower 15 are shown in FIG. Second cam 12
Due to the rotation of the second cam follower 16, the second cam follower 16 tries to move according to the second cam groove 12a, but the movement in the axial direction is restricted by the first cam groove 13a formed in the first cam 13 and the first cam follower 15. , the rotation of the second cam 12 causes the second cam follower 1 to rotate.
6 and the camshaft 14 to the pivot shaft 10, and the pivot shaft 10 rotates 90 degrees. The second cam 12 tries to rotate further, but this time the first cam 13
Since the turning direction is restricted by the first cam groove 13a and the first cam follower 15 formed in
move in the axial direction. At this time, the first cam groove 13a
Since the first cam follower 15 is guided so as to be able to move only in the axial direction, it does not rotate but only moves in the axial direction.

In order to perform the opposite movement, the motor 18 is reversed to perform the opposite movement as described above.

Next, when carrying out a series of operations for transferring articles, it is necessary to rotate the motor 18 forward, reverse, and stop, and three limit switches are used to control these operations. This will be explained.

A first gear 23 is fixed to the second shaft 17, and the rotation of the second shaft 17 is transmitted to the second shaft 17 through the first gear 23.
The signal is transmitted to gear 24. A first dog 26 and a second dog 2 are connected to the second gear 24 via a mounting plate 32.
7. The third dog 28 is fixed, and these three dogs cause the first limit switch 29,
When the second limit switch 30 and the third limit switch 31 are turned on and off, the amount of rotation of the motor 18,
Controls the direction of rotation.

On the other hand, the first article gripping device 4 and the second article gripping device 5 are operated by compressed air supplied from the hole 25a of the rotary joint 25. Compressed air supplied from the rotary joint 25 passes through a first pipe 33 and a second pipe 34 and is supplied to the two article gripping devices.

As described above, in the article transfer device of the present invention, a pivot shaft is attached to the main body so as to be movable in the axial direction and pivotable, and the pivot shaft is arranged concentrically with the pivot shaft, so that the axial motion is regulated and the pivot shaft is rotatable. It consists of a second cam, a first cam fixed to the main body, a second cam follower attached to one camshaft 14 fixed to the rotation shaft, a first cam follower, etc. This has the advantage that the transfer device can be manufactured with a simple structure without increasing its size.

That is, in the article transfer device of the present invention, the pivot axis,
The first cam and the second cam are arranged concentrically,
Moreover, one camshaft fixed to the pivot shaft passes through the first cam groove and the second cam groove.

Therefore, if the second cam is rotated relative to the first cam whose movement is restricted, the overlapping of the first cam groove and the second cam groove will change, and the rotation axis will be changed by the cam shaft passing through them. Perform rotational movement and axis movement separately.

Therefore, in the present invention, there is no need to provide separate camshafts for the axial direction and for the rotational direction, and it is possible to use only one camshaft. Moreover, since other parts such as springs are not required, the number of parts can be reduced and the structure can be simplified.

Furthermore, since neither the first cam nor the second cam moves in the axial direction, a compact structure with a reduced axial length can be realized.

[Brief explanation of drawings]

Figure 1 shows the article transfer device related to this invention.
An example of application to a workpiece changing device for an NC lathe is shown.
2 is a cross-sectional view taken along the arrow in FIG. 1, FIG. 3 is a developed view of the second cam groove 12a in FIG. 2, and FIG. 4 is a first cam groove 13a in FIG. 2.
FIG. 5 is a cross-sectional view along the - arrow in FIG. 2, and FIG. 6 is a developed view of the second cam groove 1 in FIG.
2a shows the positional relationship between the first cam groove 13a, the second cam follower 16, and the first cam follower 15. FIG. 7 shows the relationship between the rotation angle of the second cam 12 and the displacement of the pivot shaft 10 in FIG. 4...First article gripping device, 5...Second article gripping device, 6...Swivel arm, 8...Device main body, 10
... Rotating shaft, 12 ... Second cam, 13 ... First cam, 14 ... Camshaft, 15 ... First cam follower, 16 ... Second cam follower, 18 ... Motor.

Claims (1)

[Scope of Claims] 1. An article transfer device, comprising: a pivot shaft 10 built into the main body of the device so as to be movable in the axial direction and pivotable; a central portion fixed to the tip of the pivot shaft 10, and article gripping mechanisms at both ends. a cylindrical first cam 13 fixed to the apparatus main body and arranged concentrically with the pivot shaft 10; a cylindrical second cam 12 which is arranged and rotatable with axial movement restricted; one cam shaft 14 fixed to the pivot shaft 10 so as to be orthogonal to the pivot center; A first cam groove 13a is inserted into a first cam follower attached to the cam shaft and is bored in a side surface of the first cam; a second cam groove 12a, and a drive device that drives the second cam 12 in forward and reverse directions; The second cam groove 12a is formed from a corner part 12b that overlaps the arc part 13c in the turning direction, and a corner part 12b that overlaps the arc part 13c in the turning direction.
An article transfer device characterized in that it is formed from two spiral portions 12c extending from b to the straight portion 13b.