JPH0648005B2 - Precision multiple position setting cylinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to an improvement of a pneumatic or hydraulic cylinder for stopping and moving a working arm of a robot at an arbitrary position.

(B) Conventional Technology Conventionally, a pneumatic or hydraulic cylinder is used to stop the movement of the working arm of the robot. As a technique for determining the stop position of the piston rod of the cylinder, the movement of the piston rod is counted by a pulse motor or stepping motor, and when the predetermined number of pulses to reach an arbitrary position is recognized, the movement of the piston rod It was always used to stop the

(C) Problems to be Solved by the Present Invention However, pulse motors and stepping motors are expensive devices. Therefore, it is an object of the present invention to provide a cylinder that is inexpensive, precise, and capable of multiple positioning by improving the cylinder itself.

(D) Means for Solving the Problems The present invention is a precision multi-position setting cylinder having the following configuration.

Pneumatic or hydraulic cylinders.

One end of the piston rod of the cylinder is connected to an external device (for example, a robot working arm).

Pneumatic or hydraulic supply holes (air holes in the embodiment) are formed near both ends in the longitudinal direction of the cylinder.

A stopper ring having positioning grooves formed on its outer peripheral surface is inserted into about half of the piston rod in the cylinder, which is opposite to the end of the external device connecting end.

Piston rings that are hermetically sealed with respect to the inner wall of the cylinder are inserted and fixed on both sides of the stopper ring in the piston rod operating direction (before and after the piston rod moving forward and backward). As a result, the stopper ring is fixed.

A clamp claw passage window is opened near the center of the cylinder at a position between the front and rear piston rings even when the piston rod reciprocates.

A clamp cylinder equipped with a clamp claw corresponding to the positioning groove of the stopper ring is provided outside the clamp claw passage window.

Stop the movement of the piston rod by making the clamp claw jump into the positioning groove and clamping.

(E) Example An example will be described below with reference to the drawings. FIG. 1 is a sectional view showing an embodiment of the present invention. In the figure, 1 is a position setting cylinder, which may be either a pneumatic cylinder or a hydraulic cylinder, but the illustrated embodiment is a pneumatic cylinder.

The position setting cylinder has pressure air holes 14 and 1 in the cylinder head 2 and the cylinder end frame 10.
5 is almost the same as an opened normal cylinder, but two clamp claw passage windows 18 and 19 are opened above and below the center of the position setting cylinder 1 in the longitudinal direction.

One end of the piston rod 3 of the cylinder 1 can be connected to a working arm, and a half portion in the opposite direction is formed in a slightly thin shape as a mounting portion of the stopper ring 8. In FIG. 1, reference numeral 16 shown by a dotted line to surround the position setting cylinder 1 is a mounting frame.

A stopper ring 8 is aligned and fixed on one side of the piston rod 3 in the position setting cylinder 1, that is, on the right side in FIG. The stopper ring 8 may have any positioning groove 11 having a desired number and a desired pitch, but in the embodiment, one positioning groove 11 is provided at the center in order to improve accuracy.
A large number of individual stopper rings 8 formed with are used. When using the individual stopper ring 8 having only a single positioning groove 11, the stop accuracy is ± 0.0015.
The accuracy can be increased to about mm.

Each of the stopper rings 8 is as shown in the perspective view of FIG. 2, has a predetermined thickness, that is, a thickness corresponding to the pitch width according to the determined position, and has a clamp claw 5 at the center. The matching positioning groove 11 is formed in a tapered shape.

The piston rod 3 penetrates through the stopper ring 8,
The stopper ring 8 is fixed by fixing the piston rings 4 sealed on both sides to the piston rod 3.

As a result, both sides of the stopper ring 8 in the position setting cylinder 1 are sealed by the two piston rings 4, and even if the clamp claw passage windows 18 and 19 are opened near the center of the position setting cylinder 1, the position setting cylinder 1 still functions as a pneumatic cylinder. The function can be retained. In the figure, 9 is a stopper nut of the stopper ring 8 and the piston ring 4.

Clamp claw passage window 18 of position setting cylinder 1,
On the outside of 19, a clamp cylinder 6 having a clamp claw 5 matching the positioning groove 11 at the tip is attached to the mounting frame 16 with the clamp claw 5 facing the clamp claw passage windows 18 and 19. Reference numeral 7 in the drawing denotes a clamp guide for accurately guiding the clamp claw 5 to the positioning groove 11.

FIG. 3 is a cross-sectional explanatory view showing the relationship between the stopper ring 8 and the clamp claw 5. As shown in FIG. 3, the clamp claw 5 is always provided with the stopper ring 8 even when the clamp cylinder 6 is retracted. It is biased by a braking spring 17 so as to hold the outer peripheral surface.

FIG. 4 is a partially enlarged sectional view showing the mounting positions of the forward movement sensor 12 and the backward movement sensor 13 in which the clamp claw 5 and the clamp cylinder 6 are omitted. The forward movement sensor 12 and the backward movement sensor 13 can use an appropriate detection device,
Both of the sensors 12 and 13 are embedded in the clamp claw guide 7 with their detection openings opened, and are arranged at positions where the stopper ring 8 can be detected from the gap between the clamp claw 5 and the end of the clamp claw passage window 19. . The role of both sensors 12, 13 is to detect a predetermined stop position, that is, the positioning grooves 11 of the multiple stopper rings 8.

(F) Action of the Invention The present invention will be described assuming that air pressure is applied from the right side in FIG.

First, when the clamp cylinder 6 retracts from the state in which the position setting cylinder 1 is clamped at a predetermined position and stopped, the clamped state of the stopper ring 8 having the positioning groove 11 clamped by the clamp claw 5 is released. The backward movement of the clamp cylinder 6 is detected by a detection device (not shown) provided separately, and a backward movement signal is transmitted.

This retract signal causes the position setting cylinder 1 to
Pressure air is sent through the air hole 15, and the piston rod 3 moves leftward in the drawing. The moving forward sensor 12 moves the positioning groove 1 of the stopper ring 8 that moves from the gap between the clamp claw 5 and the end of the clamp claw passage window 19.
Detect 1 and count.

By counting a predetermined number, the next stop position is determined, the clamp cylinder 6 is moved forward, the predetermined positioning groove 11 is clamped by the clamp claw 5, and the piston rod 3 is accurately stopped at the positioned position. .

(G) Effect of the Invention As described above, according to the present invention, the stop position can be accurately determined only by the cylinder without using a pulse motor or the like.

Position setting cylinder 1 with clamp claw passage window 1
Even if 8 and 19 are opened or the piston rod 3 reciprocates, it is always between the sealed front and rear piston rings 4, so that the function as a pneumatic or hydraulic cylinder can be maintained.

Since the stop positioning of the piston rod 3 is performed by the positioning groove 11 of the stopper ring 8, the stop position can be arbitrarily changed only by changing the part of the stopper ring 8.

This is an application example of the present invention, but by using two position setting cylinders of the present invention to move the work arm, X
The stop position of the work arm can be determined by the biaxial operation of the Y axis, and the stop position by the XYZ triaxial operation can be determined by using three arms.

[Brief description of drawings]

1 is a sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of a stopper ring, FIG. 3 is a sectional explanatory view showing a relationship between a stopper ring and a clamp pawl, and FIG. The drawing is a partially enlarged sectional view showing the mounting positions of the forward movement sensor and the backward movement sensor. 1 …… Position setting cylinder 2 …… Cylinder head 3 …… Piston rod 4 …… Piston ring 5 …… Clamp claw 6 …… Clamp cylinder, 7 …… Clamp claw guide 8 …… Stopper ring, 9 …… Ring Stop nut 10 …… Cylinder end frame, 11 …… Positioning groove 12 …… Advance sensor, 13 …… Reverse sensor 18,19 …… Clamp claw passage window

Claims (1)

[Claims] 1. A cylinder in which a piston rod is actuated by supplying air pressure or hydraulic pressure from supply holes formed near both ends in the longitudinal direction of the cylinder, and one end of the piston rod is connected to an external device for use. Insert a stopper ring with a positioning groove on the outer peripheral surface so that multiple positioning grooves are arranged on the opposite side of the piston rod in the cylinder opposite to the external device connecting end. Insert and fix the hermetically sealed piston ring to the inner wall of the cylinder, and open the clamp claw passage window at a position near the center of the cylinder between the piston rings on both sides even when the piston rod reciprocates. Clamp cylinder equipped with clamp claws corresponding to the positioning groove of the stopper ring on the outside Provided, so jump into the clamp jaws into the positioning groove, precision number position setting cylinder, characterized in that stopping the movement of the piston rod by clamping.