JPH017876Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a fixed structure for a spiral spring, and more specifically, it is used in a reclining mechanism for a seat in a vehicle, etc., and stores kinetic energy to bias a seat back in a certain direction. Regarding the fixing structure of a spiral spring.

Conventionally, when fixing a spiral spring, the first
As shown in the figure, a groove 2 extending in the diametrical direction is formed at the tip of the mounting shaft 1, and a first bent portion 3a formed by bending inward at the inner end of the spiral spring 3 is engaged with this groove 2. Then, the second bent portion 3b formed at the outer end of the spiral spring 3 is locked to a locking piece 5 formed on the substrate 4, etc., and either the mounting shaft 1 or the substrate 4 is rotated. There are structures that accumulate kinetic energy when moved. When this spiral spring 3 is repeatedly tightened and unwound, a reaction force is applied to the vicinity of the first bent part 3a of the spiral spring 3, and the vicinity of this first bent part 3a often breaks. The durability of the spiral spring 3 was significantly reduced. In addition, in reclining mechanisms for vehicles, it is not possible to increase the size of the spiral spring 3 due to the desire to reduce the weight of the vehicle.
It is required to prevent breakage near the bending portion 3a, that is, to improve durability.

The purpose of this invention is to prevent the spiral spring from breaking near the bending part without increasing the size of the spiral spring, and therefore to significantly improve durability.
The purpose of this invention is to provide a fixing structure for a spiral spring that is simple in structure, easy to manufacture, and can improve work efficiency, which will become clear from the detailed description below with reference to the drawings.

FIG. 2 shows an outline of an embodiment in which the spiral spring fixing structure according to the present invention is applied to a reclining mechanism of a vehicle, etc. The fixing structure shown in FIG. The arm 11 has an extending mounting shaft 12 formed therein, and a base 13 having a through hole 14 into which the mounting shaft 12 is inserted. is fixed to a fixed side of a seat cushion or the like.

The mounting shaft 12 of the arm 11 is connected to the base 13.
When the arm 11 is inserted into the through hole 14 of the base 13, the arm 11 is rotatably supported by the base 13, and is held at a desired position by a lock mechanism (not shown). Hole 1
A locking piece 15 is formed at a position a certain distance away from 4.

A first bent part 17a is formed at the inner end of the spiral spring 17, and is bent inward to be engaged with a groove 18 of the mounting shaft 12, which will be described later. Locking piece 1 formed in 13
A second bending portion 17b is formed to be locked to the second bending portion 17b.

A groove 18 extending in a direction perpendicular to the axial center of the mounting shaft 12 is formed at the tip of the mounting shaft 12, and with this groove 18 as a border, the tip of the mounting shaft 12 forms a half-section 12.
a and the other half 12b. A groove 18 of the mounting shaft 12 formed at the lower part of the arm 11
One half 12a and the other half 12 formed by
b are formed in substantially the same shape, and the one half part 1
A spacer 21 made of synthetic resin, metal, etc. is attached to the space formed between the spiral spring 2a and the first bent portion 17a of the spiral spring 17 and the continuous inner end. The spiral spring 1 has approximately the same curvature as the curvature of the inner end.
The first bending section 17 of the spiral spring 17 in the free state of 7
It is designed to abut on the inner end continuous with a.

Note that a mounting portion 21a is provided at one end of the spacer 21.
is bent, and this mounting portion 21a is close to the tip of the first bent portion 17a of the spiral spring 17 and is locked in the groove portion 18 to prevent it from falling off when the spiral spring 17 is tightened and unwound. being done. Furthermore, in the above embodiment, the arm 11
A mounting shaft 14 is formed on the base 13 side, and a locking piece 1 is formed on the base 13 side.
5 is formed, but the locking piece 15 may be formed on the arm 11 side and the mounting shaft 14 may be formed on the base 13 side.

Figure 3 shows the conventional fixing structure shown in Figure 1 and the second
The graph shows a comparison of the stress distribution in each part when the spiral spring with the fixing structure of the present invention shown in the figure is wound up to the maximum.The curve X shown by the dotted line is for the conventional spiral spring, and the curve Y shown by the solid line is the stress distribution curve of the spiral spring of the present invention. As shown in the figure, the stress near the first bent portion 17a of the spiral spring according to the present invention is significantly reduced, and is changed from tensile stress to compressive stress.

The above is the configuration of an embodiment of the fixing structure for a spiral spring according to the present invention. According to this configuration, the end of the groove of the mounting shaft is circularly shaped to match the refractive curvature of the first bent part. It does not need to be formed into an arc shape, making it easy to manufacture spiral springs and significantly improving work efficiency.Also, a spacer can be retrofitted to the gap between the mounting shaft and the spiral spring, and this spacer When the spiral spring is inserted, the stress is not concentrated on the first bent part, but is dispersed over a relatively wide area that is in contact with the spacer that is further away from the first bent part, and the stress applied to the vicinity of the bent part of the spiral spring is significantly reduced. It is possible to prevent breakage near the bending part during tightening and unwinding of the spiral spring, and the durability of the spiral spring can be significantly improved compared to current ones. This method of fixing a spiral spring is highly economical because it can be made smaller and lighter, the spacer 21 can be selected according to the size of the gap, and fine adjustments can be made easily. structure can be obtained.

The above description merely shows one embodiment of the present invention, and it will be obvious that various modifications and changes can be made without departing from the spirit of the present invention.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing one embodiment of a conventional spiral spring fixing structure, and Fig. 2 is a schematic diagram showing an embodiment of the spiral spring fixing structure according to the present invention applied to a reclining mechanism of a vehicle, etc. FIG. 3 is a diagram showing the relationship between maximum deflection angle and stress for comparing the conventional fixing structure and the present invention. In the figure, 11...arm, 12...mounting shaft, 12
a... One half of the tip of the mounting shaft, 12b... The other half, 13... Base, 15... Locking piece, 17...
Spiral springs, 17a, 17b...Bending portions formed at the inner and outer ends, respectively, 18...Groove portions, 21...
...Spacer, 21a...Mounting part.

Claims (1)

[Scope of utility model registration request] a spiral spring having a first bent part bent inward at an inner end and a second bent part formed by bent outward at an outer end; A mounting shaft having a groove for locking, and a substrate having a locking piece for locking the second bending part,
an outer circumferential surface between an inner end of the spiral spring that is continuous with the first bending part and an outer circumferential surface of the mounting shaft; A fixing structure for a spiral spring, characterized in that a spacer is attached, the spacer having substantially the same curvature as the outer circumferential surface of the mounting shaft, and one end of which is locked in the groove.