JP2002307372A - Safety mechanism for rotational joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safety mechanism for a rotational joint preventing an arm or a hand of an operator from being caught by the rotational joint. SOLUTION: A fan-shaped plate 7 having a rotational axis 6 of a second arm 5 as a center is attached on a first arm 4 or the second arm 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety mechanism for preventing a worker's arm or hand from being caught in a rotary joint of an industrial robot, particularly a parallel link robot.

[0002]

2. Description of the Related Art A parallel link robot is a robot in which a plurality of sets of links are arranged in parallel between a base plate and a movable table, and the plurality of sets of links are operated to freely control the position and posture of the movable table. is there. FIG.
FIG. 1 is a conceptual diagram showing a configuration of a conventional parallel link robot. In the figure, 1 is a base plate, 2 is a movable table, and 3 is a link connecting the base plate 1 and the movable table 2. The link 3 includes a first arm 4 and a second arm 5. One end of the first arm 4 is rotatably attached to the base plate 1, and the other end of the first arm 4 is connected to the second arm 5. , And the other end of the second arm 5 is rotatably attached to the movable table 2. The first arm 4 and the second arm 5 open and close like scissors for freely changing the included angle by a drive mechanism (not shown).

[0003]

However, this parallel link robot has a first arm 4 and a second arm 5
There was a problem that the worker's arm or hand was caught between them, causing unexpected injury. Of course, in normal operation, the robot and the worker are separated by a safety fence, so there is no danger of such an accident.However, when the worker approaches the robot for repair adjustment, etc. Such an accident occurs. Accordingly, an object of the present invention is to provide a safety device for a rotating joint that prevents a worker's arm or hand from being caught by the rotating joint.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises a first arm and a second arm rotatably supported by a first arm. In a safety mechanism of a rotary joint that opens and closes an arm like scissors, a fan-shaped plate centered on a rotation axis of the second arm is attached to the first arm or the second arm. Alternatively, an openable and closable bellows is attached between the first arm and the second arm.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a structural view of a safety mechanism of a rotary joint showing an embodiment of the present invention, and FIG.
(B) is a side view. In the figure, 4 is a first arm and 5 is a second arm. The second arm 5 is pivotally supported by the first arm 4 so as to be rotatable about an axis 6,
It has a "ku" shape. Reference numeral 7 denotes a fan-shaped plate fixed to the second arm 5. The center of the sector of the plate 7 coincides with the axis 6. As shown in the side view, the plate 7
Is smaller than the gap between the first arm 4 and the second arm 5, the first arm 4 and the plate 7 are rotated when the second arm 5 rotates with respect to the first arm 4. Do not interfere with each other. Note that the plate 7 may be fixed to the first arm 4. As described above, since the rotating joint shown in the embodiment includes the plate 7, it is possible to prevent a worker's hand or arm from entering the “<” shape of the first arm 4 and the second arm 5. be able to.

FIGS. 2A and 2B are views for explaining the operation of the fan-shaped plate 7. FIG. 2A shows a state in which the angle between the first arm 4 and the second arm 5 is maximized, and FIG. ) Indicates a state in which the angle is closed to a minimum. The central angle θ of the sector is the first
The angle between the first arm 4 and the second arm 5 is larger than the maximum angle, so that even if the arm is opened to the maximum, the hand of the worker does not enter the inside of the "" shape. . Also, the radius R of the sector is selected so that a gap G is obtained such that the hand or the like of the operator is not pressed outside the sector even if the arm is closed to the minimum angle. It does not damage the hands of others.

Next, another embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a front view of a rotary joint safety device according to another embodiment of the present invention. Reference numeral 8 denotes a fan-shaped bellows attached to be sandwiched between the first arm 4 and the second arm 5. The bellows 8 expands and contracts freely in the circumferential direction of the fan, but since it is a rubber bellows having rigidity in the radial direction,
The hand or the like of the worker can prevent the hand or the arm of the worker from entering the inside of the “<” shape of the first arm 4 and the second arm 5.

As described above, according to the present invention,
Since a fan-shaped plate or bellows is provided at the rotating joint of the industrial robot, the effect of preventing accidents in which the hand or arm of the worker accidentally enters the rotating joint and pinches the worker's hand, etc. is there.

[Brief description of the drawings]

FIG. 1 is a structural view of a safety mechanism for a rotary joint according to an embodiment of the present invention, wherein (a) is a front view and (b) is a side view.

FIGS. 2A and 2B are diagrams for explaining the function of a fan-shaped plate showing an embodiment of the present invention, wherein FIG. 2A shows a state in which the angle of the rotating joint is maximized, and FIG. It shows the state that it was turned on.

FIG. 3 is a front view of a rotary joint safety mechanism according to another embodiment of the present invention.

FIG. 4 is a conceptual diagram showing a configuration of a conventional parallel link robot.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Base plate 2 Movable table 3 Link 4 1st arm 5 2nd arm 6 Axis 7 Plate 8
bellows

Claims (2)

[Claims] 1. A rotating joint safety mechanism for rotatably supporting a second arm on a first arm and opening and closing the first arm and the second arm like scissors. A safety mechanism for a rotary joint, wherein a fan-shaped plate centered on a rotation axis of a second arm is attached to the first arm or the second arm. 2. A rotating joint safety mechanism for pivotally supporting a second arm on a first arm to open and close the first arm and the second arm like scissors. A safety mechanism for a rotary joint, wherein a bellows which can be freely opened and closed is attached between a first arm and the second arm.