JPH05228882A - Stopper unit of turning device - Google Patents

Abstract

PURPOSE:To dispense with any trouble for installation besides being compact in size, and get rid of such a fear as being damaged, in a stopper unit of a turning device available in an industrial robot or the like. CONSTITUTION:This stopper unit is provided with a stationary side stopper 12 installed in a turning stationary side member 11, a piezoelectric-crystal element 16 converting a pressure variation in compressible fluid filled up in an internal closed space 15 installed in a turnable member 10 on almost the same radius with the stationary side stopper 12, into an electric signal, and a movable side stopper 13 with two piston rods 14a, 14b supported slidably in the turning direction. With this constitution, a change of pressure in the compressible fluid to be produced by contacting the piston rod 14a with the stationary side stopper 12, is detected by the piezoelectric crystal element 16 whereby any overrun is detected, while rotation of the turnable member 10 is stoppable by means of elasticity in the compressible fluid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turning device stopper device for detecting an overrun and limiting the operating range of an operating shaft of a turning device which rotates about an axis used in an industrial robot or the like.

[0002]

2. Description of the Related Art As a conventional device of this type, a stopper device for a turning device of an industrial robot will be described below.

As shown in FIGS. 3 and 4, when the robot main body rotates about the turning axis, the turning movable member 2 is moved.
Rotates in the direction indicated by the arrow A, and the adjustable overrun dog 8 attached to the turning movable member 2 is attached to the pedestal 6 for the limit switch installed on the turning fixed side member 1. By making contact with the limit switch 5 for running, overrun detection is performed, and further, the movable side stopper 7 mounted on the turning movable member 2,
The fixed stopper 3 attached to the swivel fixed member 1
By making contact with the fixed-side stopper 3 via the elastic body 4 attached thereto, the rotation of the swiveling movable member 2 is stopped and the operating range of the swiveling shaft is limited.

[0004]

However, in the above conventional structure, the limit switch 5 for overrun is used.
The installation space for the fixed side stopper 3 and the installation space for the fixed side stopper 3 need to be provided with different turning rotational diameters, which makes the turning device large, and it takes a lot of time to adjust the dog 8 for overrun, and it is fixed. Since the stoppers come into contact with each other, there is a problem that the stopper device may be damaged in some cases.

An object of the present invention is to solve the above-mentioned conventional problems, and an object thereof is to provide a stopper device for a swivel device, which is compact, hassle-free installation, and is free from damage.

[0006]

In order to achieve this object, a stop device of a swivel device of the present invention comprises a fixed stopper provided on a swivel fixed member and a fixed stopper with respect to a swivel axis. It has a piezoelectric conversion element that converts a pressure change of a compressible fluid that fills the closed space inside the swivel movable member on the same radius into an electric signal, and a piston rod that is slidably supported in the swivel direction. It is provided with a movable stopper.

[0007]

With this configuration, the piezoelectric conversion element detects the pressure change of the compressible fluid caused by the contact of the piston rod with the fixed side stopper to detect the overrun, and the elasticity of the compressible fluid is used for swirling. The rotation of the movable member will be stopped.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a movable stopper 13 is attached to the swivel movable member 10 via a pedestal 9 by a mounting bolt 17. The closed space 15 inside the movable stopper 13 is filled with a compressive fluid, and a piezoelectric conversion element 16 that converts a pressure change of the compressible fluid into an electric signal is incorporated. In addition, piston rods 14 a and 14 b are mounted on the movable stopper 13 so as to be slidable relative to the movable stopper 13 in the turning direction of the turning member 10. On the other hand, the turning fixed side member 1
A fixed-side stopper 12 is attached to 1 by a mounting bolt 18.

The operation of the stopper device of the turning device configured as described above will be described below.

When the swingable member 10 swings in the direction shown by the arrow A beyond the predetermined operating range, the piston rod 14a (14b in the case of the reverse swinging direction) abuts on the fixed stopper 12 and the piston rod 14a. The pressure change of the compressive fluid in the movable stopper 13 caused by the sliding of the movable stopper 13 in the direction indicated by the arrow B is detected by the piezoelectric conversion element 16 to detect the overrun, and the swing drive power is detected. It is possible to stop the rotation of the orbiting movable side member 10 by the elasticity of the compressive fluid.

As described above, according to this embodiment, since the turning overrun detecting means and the rotation stopping means are integrated, the turning diameter of the turning part of the turning device can be small, and the structure of the turning part can be made compact. In addition, unlike the conventional example, adjustment of the dog 8 for overrun is unnecessary, installation is not troublesome, and the elasticity of the compressible fluid is used to stop the rotation of the revolving rotary unit. Therefore, damage to the stopper device can be prevented.

[0013]

As is apparent from the above description of the embodiments, the present invention rotates the fixed-side stopper provided on the fixed-side turning member and the fixed-side stopper on the turning axis substantially on the same radius. A piezoelectric exchange element for converting a pressure change of a compressible fluid filled in a closed space provided inside a movable member into an electric signal, and a movable side stopper having a piston rod slidably supported in a turning direction. With such a configuration, it is possible to realize a compact stopper device for a swivel device, which does not require much labor for installation and is free from damage.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the concept of a main part of a stopper device of a turning device according to an embodiment of the present invention.

FIG. 2 is a schematic plan view partially showing a cross section of a main part of a stopper device of the swivel device.

FIG. 3 is a schematic plan view partially showing a cross section of a main part of a stopper device of a conventional swivel device.

FIG. 4 is a sectional view taken along line XX ′ in FIG.

[Explanation of symbols]

 10 swivel movable member 11 swivel fixed side member 12 fixed side stopper 13 movable side stoppers 14a, 14b piston rod 16 piezoelectric conversion element

Claims (1)

[Claims] 1. A fixed-side stopper provided on a swivel-fixed member and an internal closed space provided on a swivel-movable member on a radius substantially the same radius as the fixed-side stopper with respect to a swivel axis. A piezoelectric transducer for converting a pressure change of a compressive fluid into an electric signal and a movable stopper having a piston rod slidably supported in a turning direction are provided, and the piston rod comes into contact with the fixed stopper. A stopper device for a swivel device, wherein a change in pressure of the compressive fluid is detected by the piezoelectric conversion element, overrun detection is performed, and rotation of the swivel movable member is stopped by elasticity of the compressible fluid.