JPH0339628Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a stopper that limits the rotation angle of a multi-rotation mechanism and is equipped with a buffer mechanism.

(Prior art and problems) Conventionally, this type of mechanism was a pawl stopper mechanism or a sliding ring mechanism, but in the pawl stopper mechanism, the pawl stopper piece fixed to the rotating shaft and the fixed pin on the fixed side were Since the structure is such that the moving pawl stopper piece is in close contact with the shaft and the shaft can freely rotate, it has been difficult to add a buffer mechanism to the pawl portion. In addition, in the stopper ring mechanism, as shown in Fig. 3, an elastic body was attached to the stopper part 1' of the stopper ring 1, and an elastic body was added to the fixing pin 2 to soften the impact, but the contact position of the elastic body was Since the elastic body is constant, damage to the elastic body is severe and miniaturization is difficult. Furthermore, when the thickness of the elastic body is increased, there are drawbacks such as variations in the stopping angle. Moreover, the stopper ring 1 has a sliding bearing structure, and care must be taken to increase rotational torque and lubricate the sliding surface.

The present invention solves the drawbacks of the prior art, and since the contacting part of the shock absorber is not structured so that it always contacts at a fixed position, the life of the elastic body is long, and the braking effect is maintained when the rotating body stops. It also provides a stopper that gives the same effect.

(Means for solving the problem) A pair of grooves that limit the rotation angle are provided in each of the rotating body and the fixed plate facing it, and a pair of rope balls are placed on both sides with one elastic ball sandwiched between the grooves. By arranging the rotary body, the stopping of the rotating body is buffered by the elastic force of the elastic ball, and the elastic ball compressed by the two rope balls expands slightly before stopping, so that the space between it and the inner surface of the groove is reduced. It is characterized by the fact that it generates frictional resistance, which applies a brake to the rotation of the rotating body.

(Embodiment) The embodiment of the present invention shown in FIG. 1 will be explained in detail below. Components that are the same as or equivalent to those shown in FIG. 3 are given the same reference numerals.

Fig. 1 is a partial cross-sectional view of an embodiment in which a stopper of about one and a half rotations is incorporated in the rotary drive unit of the present invention, and Fig. 2 is a diagram showing the groove portion of the stopper, showing the upper surface of the fixed plate 5. A similar groove 4' is also formed on the lower surface of the rotating plate 4.
There is.

A discontinuous concentric groove 4 is provided on the fixed plate 5 (pressing plate of the bearing 8) so that the two rope balls 6 and the elastic ball 7 sandwiched between them can move freely and stop at a predetermined rotation angle. Elastic balls 7, such as balls made of urethane rubber or the like, are arranged at ' and 5', and rope balls 6 are arranged on both sides thereof.

The above-mentioned ball 3 is attached to the final end of each of the fixed plate 5 and the rotating plate 4.
The rotary plate 4 stops when it is pinched. Rotating plate 4
When stopping, the elastic ball 7 is moved by the two rope balls 6.
is compressed, so the stop does not come with a sudden impact. Furthermore, when the elastic balls 7 are pressed by the rope balls 6, they swell slightly within the grooves 4' and 5', creating frictional resistance between them and the inner surfaces of the grooves, which causes the rotating plate to apply the brakes. It will stop after the

The damping effect can be adjusted by changing the hardness of the elastic body and increasing the number of spheres in the elastic body. The position where the elastic ball contacts the steel ball is indeterminate because the elastic ball rotates freely within the groove, which significantly extends the life of the elastic ball.

(Effect of the invention) As explained above, the rope ball 6 rotating and moving in the groove comes into contact with the fixed plate 5 or the rotating plate 4, and the elastic ball 7 receives compressive force from the rope balls 6 on both sides. Since the elastic body is not subjected to shearing force, damage to the elastic body can be prevented. In addition, since the position where the elastic body contacts the rope ball is not always constant and fluctuates, the life of the elastic body is extended.

Moreover, the elastic body deforms and exhibits a buffering effect first, and then expands in the direction of the groove side surface and comes into contact with the groove side surface, increasing the braking effect and providing stable braking.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a plan view of a fixing plate in the embodiment shown in FIG. 1, and FIG. 3 is a perspective view showing a conventional stopper of this type. 1...stopper ring, 2...fixing pin, 3...
... Rotating shaft, 4... Rotating plate, 5... Fixed plate, 4',
5'... Groove, 6... Rope ball, 7... Elastic ball.

Claims (1)

[Scope of utility model registration request] A rotating plate fixed to a rotating shaft, a fixed plate disposed opposite to the rotating plate, and a cross section provided on each opposing surface of the rotating plate and the fixed plate having a substantially semicircular shape. A multi-rotation stopper with a shock absorbing mechanism is comprised of a groove, a small ball made of an elastic body that can freely rotate within the groove, and a pair of rope balls arranged on both sides of the small ball.