JPH068348Y2 - Spring brake device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a spring brake device used for a seat lifter or a window regulator of a vehicle seat.

"Prior Art" A conventional spring brake device is disclosed in
There is one such as that disclosed in JP-A-61-294227.

That is, the core and the pinion are rotatably housed in the brake drum body, the core is engraved with a fan-shaped notch, and the claws of the pinion are inserted into the fan-shaped notch with a gap on both sides. The main coil spring is press-fitted to the first braking surface, which is the inner wall surface of the diameter cylinder, and both ends of the main coil spring are inserted into the gaps on both sides of the claw portion of the pinion, and the outer wall surface of the small diameter cylinder. The sub-coil spring is press-fitted to the second braking surface, one end of the sub-coil spring engages with the claw portion of the pinion, and the other end is inserted between the cut edge of the notch and the end of the main coil spring. It was the one.

[Problems to be solved by the invention] However, in such a conventional spring brake device, a large number of things such as both ends of the main coil spring, both ends of the sub coil spring, and claws of the pinion are provided in the notch of the core. Since the parts are inserted, the allowable tolerances of the respective parts are piled up, and the tolerance of the positional relationship between the parts becomes large.

As a result, it becomes very difficult to position the parts for assembly, and especially for the end of the sub-coil spring, it must be inserted between the end of the main coil spring and the cut edge of the notch of the core. There is a problem in that it is necessary to reduce the tolerance and improve the accuracy of each part because the parts may not be correctly assembled due to the variations in the above and the brakes may not be applied, resulting in an increase in cost.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a spring brake device capable of easily positioning the parts to be assembled without increasing the cost. There is.

"Means for Solving Problems" The gist of the present invention for achieving such an object is to have a large-diameter large cylinder inner wall surface and a small-diameter small cylinder outer wall surface having the same cylinder central axis. A notch for fitting is formed in a brake drum main body and a fitting insertion portion that is rotatably supported by the brake drum main body and that fits in a cylindrical gap between the large cylinder inner wall surface and the small cylinder outer wall surface. In addition, an input-side rotating body having a locking projection protruding toward the outer wall surface side of the small cylinder in the fitting insertion section, and an input-side rotating body rotatably pivotally attached to the input-side rotating body, with engaging projections on both sides. An output side rotating body fitted with a notch for fitting with a clearance for insertion, a first coil spring pressed into contact with the inner wall surface of the large cylinder, and both ends thereof inserted into the clearance for insertion, respectively. Pressed against the outer wall of a small cylinder, one end of which is the engaging protrusion Engage, it consists in a spring brake device and the other end upon rotation of one direction and a second coil spring which abuts on the locking projection.

[Operation] To assemble the spring brake device, the first coil spring is pressed into contact with the inner wall surface of the large cylinder of the brake drum body, and the second coil spring is pressed into contact with the outer wall surface of the small cylinder. Next, both ends of the first coil spring are inserted into the gaps between the notch for fitting the input side rotating body and the engaging protrusion of the output side rotating body, respectively, and one end of the second coil spring is engaged. If the second coil spring is engaged with the protrusion, the other end of the second coil spring is automatically arranged at a position where it can come into contact with the locking protrusion, so that the second coil spring can be easily positioned.

As the operation of the spring brake device, when the input side rotating body rotates, the notch for fitting pushes the end portion of the first coil spring to change the coil diameter and rotate the input side rotating body. If the rotation of the body is in one direction, the locking projection pushes the other end of the second coil spring, the second coil spring rotates by changing the coil diameter, and the notch for fitting is the engaging projection part forward and backward. Is pushed in, the output side rotating body rotates without being restrained by the second coil spring.

If the rotation of the input side rotating body is in the other direction, the notch for fitting pushes the engaging protrusion, the engaging protrusion bends the end of the second coil spring, and the second coil spring changes the coil diameter. The output side rotating body is rotated without being restricted by the second coil spring.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention.

As shown in FIG. 1 and FIG. 2, the brake drum body 10 has a large-diameter inner wall surface 1 of a large diameter having the same cylinder center axis.
2 and a small cylindrical outer wall surface 14 having a small diameter. The inner wall surface 12 of the large cylinder and the outer wall surface 14 of the small cylinder serve as a braking surface of the coil spring.

An input shaft 22 of a core 20, which is an input-side rotating body, is rotatably fitted in the small cylindrical portion 16 of the brake drum body 10. A cylindrical fitting insertion portion 24 is fitted in the cylindrical clearance between the large cylindrical inner wall surface 12 and the small cylindrical outer wall surface 14, and a fan-shaped notch 26 for fitting is formed in the fitting insertion portion 24. It is set up. Further, the fitting insertion portion 24 is formed with a locking projection 28 that projects toward the small cylinder outer wall surface 14 side.

The input shaft 22 of the core 20 penetrates the main body of the core 20 and projects to the opposite side, and the projecting portion serves as a pinion shaft 29, and the pinion 30 is rotatably attached to the pinion shaft 29. A protrusion member 33 having an engagement protrusion 34 that is fitted into the notch 26 for fitting is fixed to the pinion 30. The pinion 30 and the protrusion member 33 are the output side rotating body. A gap a for insertion is provided on both sides of the fitted engagement protrusion 34.

A first coil spring 40 is press-fitted onto the inner wall surface 12 of the large cylinder, and both ends 42 and 43 of the first coil spring 40 are inserted into the insertion gap a.

The relationship between the first coil spring 40 and the core 20 is such that when the core 20 rotates clockwise in FIG.
The cutting edge 26b of 6 pushes the end portion 42 of the first coil spring 40 so that the diameter of the first coil spring 40 is reduced, and when the core 20 rotates in the counterclockwise direction in FIG. The cut edge 26a of the notch 26 pushes the end portion 43 of the first coil spring 40, and the diameter of the first coil spring 40 is reduced.

On the other hand, the second coil spring 50 is pressed against and fitted to the outer wall surface 14 of the small cylinder. One end 52 of the second coil spring 50 is engaged with the slit 35 of the engaging projection 34, and the other end 53 of the second coil spring 50 is the locking projection 2.
It is arranged in hope of eight.

The relationship between the end portion 53 of the second coil spring 50 and the locking projection 28 is such that when the core 20 rotates clockwise in FIG.
The core 20 receives the second coil spring 50 via the engaging protrusion 34.
Before attempting to reduce the diameter, the other end 53 comes into contact with the locking projection 28, and the second coil spring 50 expands in diameter and rotates.

Next, the operation will be described.

As a method of assembling the spring brake device, the first coil spring 40 is press-fitted onto the inner wall surface 12 of the large cylinder of the brake drum body 10 and the second coil spring 50 is attached.
Is pressed against and fitted to the outer wall surface 14 of the small cylinder.

Next, the first coil spring 40 is provided in the gap a between both the notch 26 for fitting the core 20 and the engaging protrusion 34 on the pinion 30 side.
Both end portions 42 and 43 of each are inserted. Both ends 42, 43 of the first coil spring 40 are provided in both gaps a.
Since other parts are not inserted, there is no need to consider the mutual positional relationship with other parts, and it is possible to assemble very easily.

At this time, if one end 52 of the second coil spring 50 is engaged with the slit 35 of the engagement protrusion 34, there is some variation in the position of the other end 53 of the second coil spring 50. Also, the other end portion 53 is arranged at a position where it can automatically come into contact with the locking projection 28, and there is no need to adjust the position, and it can be easily assembled.

Next, the operation of the spring brake device will be described.

In FIG. 2, when the pinion 30 side is rotated in the clockwise direction, the side end 34a of the engaging protrusion 34 is moved to the first coil spring 40.
The first coil spring 40 expands in diameter and presses against the inner wall surface 12 of the large cylinder more strongly,
Since the diameter of the second coil spring 50 is reduced and pressed against the outer wall surface 14 of the small cylinder more strongly, the second coil spring 50 does not rotate and therefore the core 40
Does not rotate.

In FIG. 2, when the pinion 30 side rotates counterclockwise, the engagement protrusion 34 causes the end portion 52 of the second coil spring 50 to rotate.
The second coil spring 50 expands in diameter, the braking force of the outer wall surface 14 of the small cylinder weakens, and the second coil spring 50 rotates. Pinion 3
When the 0 side rotates counterclockwise, the side end 34b of the engaging protrusion 34 abuts against the end 42 of the first coil spring 40 and the end 4
Push in 2. Before and after, as shown in FIG. 3, the end portion 53 of the second coil spring 50 comes into contact with or comes close to the locking projection 28. When the side end 34b of the engaging protrusion 34 pushes the end 42 of the first coil spring 40, the diameter of the first coil spring 40 is expanded, and the first coil spring 40 is pressed against the outer wall 12 of the large cylinder more strongly, so that the first coil spring 40 does not rotate. The core 20 also does not rotate.

In FIG. 3, when the pinion 30 side is returned in the clockwise direction, the engagement projection 34 on the pinion 30 side causes the end 52 of the second coil spring 50 to bend to the opposite side, but the second coil spring 50 Since the diameter of the pinion 30 is reduced and strongly pressed against the outer wall surface 14 of the small cylinder, the pinion 30 does not rotate not only in the counterclockwise direction but also in the clockwise direction and does not rattle. Further, the core 20 is
Since the locking projection 28 is in contact with or close to the end portion 53 of the second coil spring 50, there is no play in the clockwise direction, and the cut edge 26a of the notch 26 for fitting has the end portion 43 of the first coil spring 40. Since there is no counterclockwise play,
Does not cause backlash.

In FIG. 2, when the core 20 is rotated in the clockwise direction, the cut edge 26b of the notch 26 for fitting pushes the end portion 42 of the first coil spring 40, and the first coil spring 40 contracts to have a large diameter inside the large cylinder. The braking force of the wall surface 12 weakens and the wall 12 rotates clockwise. When the core 20 is further rotated in the clockwise direction, the cut edge 26b of the notch 26 for fitting is moved to the end portion 4 of the first coil spring 40.
2, the side end 34 of the engaging projection 34 on the pinion 30 side
I try to push b. However, since the locking projection 28 flexes the end portion 53 of the second coil spring 50 and the diameter of the second coil spring 50 is expanded in advance, the engagement projection 34 rotating clockwise causes the second coil spring 50 to move. The second coil spring 50 rotates clockwise and the pinion 30 also rotates clockwise without contraction.

When the rotation is stopped while the core 20 and the pinion 30 are rotating clockwise, the expanded diameter of the second coil spring 50 is reduced by the restoring force, and the end portion 53 of the second coil spring is locked. Pushing the protrusion 28, the core 20 is slightly returned counterclockwise, and the state shown in FIG. 3 is obtained.

In the state shown in FIG. 3, the core 20 has the locking projection 28.
Is in contact with the end 53 of the second coil spring 50, and the cut edge 26a of the notch 26 for fitting is in contact with the end 43 of the first coil spring 40. No, there is no play.

In FIG. 2, when the core 20 is rotated counterclockwise,
The core 20 reduces the diameter of the first coil spring 40 and rotates it, and at the same time, enlarges the diameter of the second coil spring 50 through the engaging protrusion 34, rotates the pinion 30, and rotates the second coil spring 50. Let

According to the spring brake device of the above-described embodiment, as shown in FIG. 3, the engaging protrusion 34 has the first coil spring 40.
By contacting the end portion 42 of the pinion 30, it is possible to make the pinion 30 incapable of rotating in either the clockwise or counterclockwise direction.

[Advantage of Invention] According to the spring brake device of the present invention, one end of the second coil spring is provided at a position away from the fitting notch where many parts are densely packed, so that the fitting notch is often provided. The parts are not clustered, the tolerance of the positional relationship accuracy between the parts can be made large, the accuracy of each part does not need to be increased, the cost does not increase, and the assembly positioning can be facilitated.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention.
FIG. 2 is an exploded perspective view of the spring brake device, FIG. 2 is a sectional view of a main part of the same, and FIG. 10 ... Brake drum main body 12 ... Large cylinder inner wall surface, 14 ... Small cylinder outer wall surface 20 ... Core (input side rotating body), 22 ... Input shaft 26 ... Notch for fitting, 28 ... Locking Protrusion 30 ... Pinion, 34 ... Engaging protrusion 40 ... First coil spring 42, 43 ... End of first coil spring 50 ... Second coil spring 52, 53 ... End of second coil spring Department

Claims (1)

[Scope of utility model registration request] 1. A brake drum main body having a large-diameter large cylinder inner wall surface and a small-diameter small cylinder outer wall surface having the same cylinder central axis, and a rotatably supported rotatably supported by the brake drum main body. A notch for fitting is formed in a fitting insertion portion that fits in a cylindrical gap between the wall surface and the outer surface of the small cylinder, and a locking projection that protrudes toward the outer wall surface of the small cylinder is formed in the fitting insertion portion. A formed input side rotating body; and an output side rotating body that is rotatably pivotably attached to the input side rotating body and has engaging protrusions fitted in the notches for insertion with gaps for insertion on both sides. A first coil spring that is pressed against the inner wall surface of the large cylinder and has both ends inserted into the insertion gaps, and is pressed against the outer wall surface of the small cylinder, one end of which engages with the engaging protrusion, A second coil spring, the other end of which abuts on the locking projection when rotating in the direction of A spring brake device comprising: