JP2558211Y2 - Spring brake device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring brake device which allows rotation to be transmitted from an input shaft to an output shaft, but prevents rotation in the reverse direction. This type of device is used for a window regulator of a vehicle and a seat height device for vertically adjusting a seat.

[0002]

2. Description of the Related Art Conventionally, a spiral spring is pressed into a substantially cup-shaped housing, and when the hook end of the spring is operated in a winding direction, rotation is allowed.
There is known a device that makes a rotation impossible by operating a brake when a hook end is operated in an expanding direction, and various devices have been proposed (Japanese Patent Publication No. 1-51695, Japanese Patent Application Laid-Open No. 58-191327). JP-A-58-146726
issue). In particular, in the seat height device for adjusting the seat up and down, the feeling is remarkably reduced when the backlash is generated due to the load on the output shaft side. Therefore, two spiral springs having a symmetrical action with respect to the rotation in both the left and right directions are employed. The use of brake devices has become common. In these seat height devices, in addition to supporting the load of the seat weight plus the weight of the seated occupant, it is necessary to use sintered metal for the transmission part of the braking device to support the impact load during sitting and running. To ensure proper strength.

[0003]

However, there is a problem that it is difficult to weld the sintered metal to the output shaft because it is difficult to weld the sintered metal. Further, when the output shaft is swaged to the sintered metal part, the sintered metal part is liable to crack. Therefore, in the conventional apparatus, the output shaft is formed integrally with the sintered metal, or the pinion gear is formed integrally with the sintered metal, and the force is transmitted to the output shaft via the pinion gear. . For this reason, in the conventional apparatus, there was a problem that the sintered metal member was increased in size and complexity and the cost was increased. The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to limit the sintered metal member to the original action of engaging with the hook end of the spring and transmitting the force. It is an object of the present invention to provide a spring brake device which can be formed into a shape and which can be reliably connected to an output shaft.

[0004]

In order to achieve the above object, according to the present invention, the cup-shaped housing 1 and the hook portions 2A, 2B, 3A, 3A are pressed against the inner peripheral wall of the housing 1.
One of two torsion springs 2 and 3 with B projecting inward and one of hook portions 2B and 3A fixed to a rotatable input shaft 5 and provided on one of the two torsion springs. First engageable with play
The driving member 4 is fixed to a rotatable output shaft 8,
And a second drive member 7 locked to hooks 2A, 3B provided on the other of the two torsion springs, wherein the second drive member 7 is formed of a sintered metal, The second drive member 7 and the output shaft 8 are fixedly attached to the plate 6 fixed to the output shaft 8 in concave portions 61 and 62 provided in the plate 6, and the convex portion 74 provided in the second drive member 7. 75 is provided, and a spring brake device is provided.

[0005]

In the spring brake device constructed as described above, the connection between the second drive member 7 made of sintered metal and the output shaft 8 is performed via the plate 6, and the plate 6 and the second drive member 7 are connected to each other. 2 is connected to the second driving member 7.
This is performed by press-fitting the convex portions 74 and 75 provided on (sintered metal). The convex portions 74 and 75 of the sintered metal are resistant to stress in the compression direction, and do not crack.

[0006]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of the spring brake device. Two spiral torsion springs 2 and 3 are stored in a cup-shaped housing 1 so as to press the outer peripheral portion against the inner peripheral wall surface of the housing 1. Each of the torsion springs 2 and 3 has two hook portions 2 on the inner peripheral side.
A, 2B, 3A and 3B are projected.

The first drive member 4 having edges 4A, 4B engaged with the hooks 2B, 3A comprises a substantially disc-shaped bottom wall and a semi-cylindrical side wall. Hole 41
, The input shaft 5 is inserted and fixed by welding. The first driving member 4 to which the input shaft 5 is fixed and integrated is housed in the cup-shaped housing 1 such that its outer peripheral surface is in sliding contact with the torsion springs 2, 3. From the hole 11. In this assembled state, both end edges 4A and 4B of the semi-cylindrical side wall of the first driving member 4 are connected to one of the torsion springs 3.
3A and the right hook 2B of the other torsion spring 2 can be engaged with play.
The rear end face of the input shaft 5 is provided with a hole 51 into which the tip of the output shaft 8 is inserted.

The second drive member 7 to which the output shaft 8 is fixed has a substantially disk-shaped bottom wall and a semi-cylindrical side wall.
It is integrally formed of sintered metal. The torsion spring 2 is provided on the semi-cylindrical side wall of the second drive member 7.
Longitudinal grooves 71, 7 for locking the hook portions 2A, 3B
2 are formed. A hole 73 for inserting the output shaft 8 with a play is provided at the center of the substantially disk-shaped bottom wall, and two projections 74 and 75 are provided around the bottom wall. A plate 6 made of a steel material having concave portions 61 and 62 into which the convex portions 74 and 75 are press-fitted is prepared. A hole 63 is provided in the center of the plate 6, and the output shaft 8 is inserted into the hole 63, and the plate 6 and the output shaft 8 are integrally fixed by welding. The plate 6 is fixed to the second driving member 7 by pressing the concave portions 61 and 62 of the plate 6 into the convex portions 74 and 75 of the second driving member 7. That is, the output shaft 8 is fixed to the second drive member 7 via the plate 6. At this time, the press-fitting stress is absorbed by the deformation of the concave portions 61 and 62 of the plate 6 in the spreading direction, and the convex portions 7 of the second driving member 7 are absorbed.
4 and 75 are subjected to a stress in the compression direction.

The second drive member 7 integrated with the output shaft 8
Is incorporated in the housing 1 so as to face the first drive member 4. At this time, the left hook portion 2A of the one torsion spring 2 is connected to the one vertical groove 7 of the second drive member 7.
1, the right hook 3B of the other torsion spring 3
Are locked in the other vertical groove 72 without play. Then, the tip of the output shaft 8 is inserted into the hole 51 at the shaft end of the input shaft 5. The other end of the output shaft 8 is a washer 9 and a cover 1
0 through the hole 101 at the center. Cover body 1
0 is integrated with the housing 1 with its peripheral edge swaged.

FIG. 2 is a sectional view for explaining the operation. When the input shaft 5 is driven to rotate clockwise (in the direction of arrow F in the figure), the first driving member 4 rotates clockwise, and its edge 4B presses the hook 2B of the first torsion spring 2 torsion. The spring 2 is pressed in a winding direction.
Then, the first torsion spring 2 is compressed, the frictional force with the housing 1 is reduced, the rotation of the first torsion spring 2 becomes possible, and the first drive member 4 further rotates. When the first drive member 4 rotates, the edge 4B thereof comes into contact with the second drive member 7, and presses the second drive member 7 in a clockwise direction. Then, the hook portion 3B locked in one of the vertical grooves 72 of the second driving member 7 is pressed to press the second torsion spring 3 in a winding direction, and the second torsion spring 3 is compressed to be pressed into the housing. Release the braking force due to friction with 1. After the braking force is released, the second drive member 7, the plate 6, and the output shaft 8 are pressed and rotated together as a result of the rotation of the first drive member 4.

Similarly, when the input shaft 5 is driven to rotate counterclockwise, the edge 4A of the first drive member 4 presses the hook 3A to wind up the second torsion spring 3 and the braking force. Is released, and then the hook portion 2A locked in the vertical groove 71 of the second driving member 7 is pressed to wind up the first torsion spring 2 and release its braking force.

Conversely, when a rotational force acts on the output shaft 8, the second
Drive member 7 attempts to rotate in either direction,
A force acts on one of the two torsion springs 2 and 3 in a direction to increase the diameter, the frictional force with the housing 1 increases, the braking force is strengthened, and the output shaft 8 does not rotate. For example, when a force acts on the output shaft 8 in the clockwise direction, a force acts on the hook portion 2A in a direction in which the diameter of the first torsion spring 2 increases, and when a force acts on the output shaft 8 in the counterclockwise direction, the hook portion 2A. A force acts on 3B in a direction to increase the diameter of the second torsion spring 3.

As described above, in this embodiment, the connection between the second drive member 7 made of sintered metal and the output shaft 8 is performed via the plate 6, and the plate 6 and the second drive member 7 are connected to each other. The connection with the driving member 7 is performed by press-fitting the convex portions 74 and 75 provided on the second driving member 7 (sintered metal). The convex portions 74 and 75 of the sintered metal are extremely strong against stress in the compression direction. For this reason, the shapes of the convex portions 74 and 75 need only consider the shearing resistance required for transmitting the rotational force. Further, since the diameter of the hole 73 of the second drive member 7 is set slightly larger than the output shaft 8 so that the output shaft 8 can be inserted with a play gap, the force applied to the output shaft 8 is reduced by two convex portions 74, 75 evenly distributed. In addition, it is clear that the convex portions 74 and 75 are not limited to two places, and may be provided in three or more places.

[0014]

According to the present invention, the coupling between the second drive member, which is a sintered metal member having the above-described structure, and the output shaft is performed by press-fitting through a plate. The metal member can be formed in a simple shape limited to the original action of engaging with the hook end of the spring and transmitting the force, and there is an excellent effect that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a spring brake device.

FIG. 2 is a cross-sectional view illustrating the operation.

[Explanation of symbols]

 Reference Signs List 1 housing 2, 3 torsion spring 4 first drive member 5 input shaft 6 plate 7 second drive member (sintered metal member) 8 output shaft 61, 62 recess 74, 75 projection

Claims (1)

(57) [Scope of request for utility model registration] 1. A cup-shaped housing, and two torsion springs which are to hook pressed against the inner peripheral wall of the housing projects into the inner peripheral side is fixed to the freely input shaft said two torsion One of the springs
A first drive member engageable with clearance in one of the hook portions provided on, is fixed to the movable output shaft rotation the 2
One of the spring brake device and a second driving member to be engaged with the other full Tsu <br/> click portion provided in the other of the torsion spring, the second drive member of a sintered metal The second drive member is fixed to the output shaft by pressing a projection provided on the second drive member into a recess provided on a plate fixed to the output shaft. Features a spring brake device.