JPH07253127A - Rotation axis rotation stop mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] Expand the range of rotation and simplify the structure. [Structure] A groove 4 having a predetermined depth is circumferentially formed on the surface of a rotary shaft 1 which is rotatably fitted in the shaft hole 3, and a recess 6 having a predetermined depth is also circumferentially formed in the shaft hole 3. Form. A space having the sum of the depths of the groove 4 and the recess 6 is formed in the overlapping portion, and the ball 7 is inserted into the space. The outer diameter of the ball 7 is substantially equal to the height of the space in which it is stored. When the rotary shaft 1 is rotated, the ball 7 rotates and revolves at an angular velocity almost half that of the rotary shaft 1. When the ball 7 reaches the end of the recess 6, the revolution is stopped and only the rotation occurs. When the rotary shaft 1 is further rotated in this state,
The protrusion 5 makes one round and rotates until it reaches the ball 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation shaft detent mechanism used in a rotation mechanism section for limiting the rotation range of a rotation shaft to a predetermined range.

[0002]

2. Description of the Related Art Conventionally, in order to limit the range of rotation of a shaft supported by a bearing in a rotatable state, a rotation stopping mechanism is provided. Generally, the engaging portion is formed on the surface of the rotating shaft, the engaging member is provided on the bearing side in a protruding manner, and when the rotating shaft rotates by a predetermined angle, the engaging portion and the engaging member are separated from each other. Some come into contact with each other to prevent rotation.

[0003]

However, in this mechanism, the rotation range of the rotary shaft is an angle obtained by subtracting the angle occupied by the engaging portion in the rotation direction from one rotation, and is less than one rotation. Therefore, in order to obtain a rotation range that exceeds one rotation, it is necessary to connect gears or the like to these detent mechanisms to amplify the rotation angle, which causes a problem that the mechanism becomes complicated. It was The present invention has been made to solve the above problems, and an object of the present invention is to provide a rotation stopping mechanism for a rotating shaft capable of setting a rotation range exceeding one rotation.

[0004]

In order to achieve the above-mentioned object, the present invention provides a concave portion having a constant depth formed in a part of the surface of the rotating shaft in the direction of rotation, and rotatably fitted to the rotating shaft. A recess having a constant depth formed in the rotational direction of the inner surface of the shaft hole to be fitted and having a constant depth, and inserted into a space formed by overlapping the two recesses in a state where the rotary shaft is fitted in the shaft hole, And a rotating body having a diameter substantially equal to the dimension of the space in the thickness direction.

[0005]

In the present invention, in the space where the rotary shaft and the recess of the shaft hole are overlapped with each other while the rotary shaft is fitted in the shaft hole,
A rotating body having a diameter approximately equal to the thickness dimension of the space is inserted. As a result, when the rotation shaft and the shaft hole rotate relatively,
The rotating body rolls in the circumferential direction in the spaces displaced from each other. When the two recesses are displaced and the ends of the two recesses approach each other, the rotating body is sandwiched between the end portions, and further rotation of the rotating shaft and the shaft hole is stopped.

When the rotary shaft and the shaft hole are rotated in the opposite directions from this state, the rotary body rolls in the circumferential direction again, but when the ends of the both recesses located at the positions opposite to those before approach, the rotary body rotates. The body is likewise pinched between the ends, and further rotation of the rotary shaft and shaft bore is restrained. In this way, the rotation range of the rotary shaft and the shaft hole, which is restricted by the both concave portions and the rotating body, is obtained as the sum of the lengths of the both concave portions. More precisely, it is the sum of the angles by which the rotating body can revolve and move in both recesses, and the value is close to a maximum of two rotations.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a transverse sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA of FIG. In both figures, 1 is a rotary shaft, and the rotary shaft 1 is rotatably inserted through a shaft hole 3 formed in a bearing 2. It should be noted that the thrust direction and the radial direction are fixed between the rotary shaft 1 and the bearing 2 at a portion not shown. Further, the rotary shaft 1 is formed with a groove 4 as a recess having a predetermined depth in the circumferential direction on the surface thereof, and the length of the groove 4 extends over substantially the entire circumference except some unprocessed protrusions 5.

A recess 6 having a predetermined depth is formed in the shaft hole 3 in the circumferential direction. A space having the sum of the depths of the groove 4 and the recess 6 is formed in the overlapping portion. The ball 7, which is a rotating body, is inserted into this space. The outer diameter of the ball 7 is substantially equal to the height of the space in which it is stored. When the rotary shaft 1 is rotated counterclockwise from the state shown in FIG. 1, the ball 7 rotates clockwise in the clockwise direction and revolves counterclockwise at almost half the angular velocity of the rotary shaft 1. When the ball 7 reaches the upper left end of the recess 6, the revolution is stopped and only the rotation occurs. In this state, the rotary shaft 1 continues to rotate counterclockwise. Then, the protrusion 5 makes one round and reaches the lower right of the ball 7, and presses the ball 7 to stop the rotation.

Next, when the rotary shaft 1 is rotated in the opposite clockwise direction, the ball 7 rotates counterclockwise and revolves clockwise in an angular velocity almost half that of the rotary shaft 1. When the ball 7 reaches the lower right end of the recess 6, the revolution is stopped and only the rotation occurs. From this state, the rotary shaft 1 continues to rotate further clockwise. Then, the protrusion 5 makes a round and reaches the upper left of the ball 7, presses the ball 7, and the rotation is stopped. The rotation range of the rotary shaft 1 when the rotary shaft 1 is rotated in both directions in this way is, as can be seen by focusing on the rotation range of the protrusion 5 of the rotary shaft 1, in addition to one rotation, it is almost concave. The angle is 6 plus the length. That is, the rotation of the rotary shaft 1 can be restricted within the range of the rotation angle of 360 degrees or more.

Although not shown here, if the recessed portion 6 is further lengthened to leave a part of the unmachined portion and has a length close to the entire circumference, the rotation range of the rotary shaft 1 can be expanded to an angle close to two rotations. That is, in this mechanism, the angle at which the ball 7 can revolve in the groove 4 of the rotary shaft 1 and the ball 7 in the recess 6 of the shaft hole 3.
Is the rotation range of the rotary shaft 1. As described above, in the embodiment, the groove 4 and the recess 6 having the length for obtaining the required rotation angle are formed in the rotation shaft 1 and the shaft hole 3, respectively, and the ball 7 is inserted between them, and the structure is almost 2 It is possible to obtain a rotation stopping mechanism for a rotation shaft that regulates an arbitrary rotation angle within a rotation range close to rotation.

Although the ball 7 is used as the rotating body in the embodiment, a roller may be used. Further, in the embodiment, the groove 4 is formed on the rotary shaft 1 and the recess 6 is formed on the shaft hole 3. However, the recess may be formed on the rotary shaft 1 and the groove may be formed on the shaft hole 3, or both may be formed. Is also possible.

[0012]

As described above, according to the present invention, it is extremely simple to form a recess in the rotating shaft and the shaft hole which rotate relative to each other, and insert the rotary body in the space formed by the recess. Due to the mechanism, a rotation range of up to 2 rotations can be obtained. This rotation stop mechanism for rotating shafts is used in various industrial fields, including the rotating part of manipulators that are rotated.
It can be used for a rotation mechanism section that limits the rotation range to a predetermined range.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

[Explanation of symbols]

 1 rotary shaft 2 bearing 3 shaft hole 4 groove 5 protrusion 6 recess 7 ball

Claims (1)

[Claims] 1. A recess having a constant depth formed in a part of the surface of the rotating shaft in the rotating direction, and a part of the inner surface of the shaft hole rotatably fitted to the rotating shaft in the rotating direction. And a rotary body having a diameter substantially equal to the dimension of the space in the thickness direction, which is inserted into a space formed by overlapping the recess with the fixed depth and the rotary shaft fitted in the shaft hole. And a rotation stop mechanism for the rotating shaft.