JP3018566B2 - Seat reclining mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat reclining mechanism suitable for a seat in which a three-point seat belt is integrally incorporated in a seat.

[0002]

2. Description of the Related Art Vehicle seats are required to be comfortable and safe for occupants. One means for providing comfort to the occupant is a reclining mechanism for tilting the seat back, and a means for ensuring safety for the occupant is a seat belt.

[0003] Seat belts include a lap belt for restraining the waist, a shoulder belt for restraining the upper torso, their anchor portions, and a retractor. Attention is paid to a built-in type in which the belt is tensioned only when the occupant is restrained. In this type, both anchor portions are provided on a lower arm supporting a seat cushion, and the retractor is disposed outside the headrest.

[0004] When a vehicle in which such a seat is installed causes a frontal collision, a large load acts on the shoulder anchor portion due to the tension of the shoulder belt. That is, a large force acts on one side of the seat back frame, and the seat back frame is twisted.

[0005] The torsion of the seat back frame creates a rotational moment in the seat reclining mechanism. The seat reclining mechanism has a configuration in which the internal teeth of the upper arm that supports the seat back frame and the external teeth of the lower arm that supports the seat cushion frame, but the action of a high rotational moment on this configuration causes the teeth to break. , Making the reclining operation difficult.

[0006]

In order to cope with the action of the high rotational moment on the reclining mechanism, means for increasing the tooth thickness is considered, but this is not practical because the operating force is heavy.

Therefore, an object of the present invention is to solve the above-mentioned disadvantages of the prior art.

[0008]

According to the present invention, in order to solve the above-mentioned problem, a pair of internal and external teeth are meshed, that is, a pair of lower arms and a pair of upper arms are arranged on one side of a seat, and one of the internal teeth is provided. Means for making the shift coefficient of the gear larger than the shift coefficient of the other internal gear is adopted.

[0009]

[Function] In normal times, one of the pair of internal and external gears enables reclining of the meshing sheet. In the event of an accident, slight tooth deformation causes the other internal and external gears to mesh with each other. To receive.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, in a seat 1, an upper arm 3 on a seat back 2 side and a lower arm 5 on a seat cushion 4 side are connected via a reclining mechanism 6.

FIG. 2 shows the reclining mechanism 6 on the shoulder anchor portion side. It consists of two sets of teeth, one of which supports one upper arm 10 via a bearing 9 on an eccentric shaft 8 of a shaft 7. The internal gear 11 is formed on the upper arm 10.

A sleeve 13 is attached to the center axis 12 of the shaft 7.
The lower arm 5 and a latch gear 14 that forms a part of the lower arm are supported via the lower arm 5. External teeth 15 are formed on the latch gear 14 that forms a part of the lower arm 5. The external teeth 15 mesh with the internal teeth 11, and the number of the external teeth 15 is one less than the number of the internal teeth 11. The latch gear 14 is connected to the sleeve 13 and the lower arm 5.

The meshing of the teeth on the left side of the eccentric shaft portion 8 of the shaft 7 has been described. Since the meshing of the teeth on the right side is symmetrical to that on the left side, the corresponding parts are indicated by the same numbers with dashes. The upper arms 10 and 10 'are fixed to each other by
To be supported.

The shift coefficient of one internal gear 11 is made larger than the shift coefficient of the other internal gear 11 ', and the backlash between the internal teeth and the external teeth is increased by, for example, 0.1 to 0.2 mm.

As shown in FIG. 4, the module of the combination of the two teeth is changed so that a gap 17 is formed on one tooth surface.
Alternatively, the meshing height of the teeth may be different for each combination of teeth.

When the handle 18 is rotated, the eccentric shaft 8
Pivots about the axes of the concentric shaft portions 12, 12 ',
Change the meshing position of the internal and external teeth. One rotation of the handle 18 tilts the upper arm by one internal tooth.

The reclining of the seat back 2 is obtained by meshing one of the internal teeth 11 and the external teeth 15 by operating the steering wheel in a normal state. An engagement between the tooth 11 'and the external tooth 15' occurs, and the combination of both teeth 11, 15, 11 ', 15'
Since the load acting on the reclining mechanism 6 is received, there is no damage to the teeth.

[0018]

According to the steering wheel operation in the normal state, only one of the pair of teeth is engaged, so that the operating force does not increase. On the other hand, if the load is large as in the case of an accident, the meshing portion is deformed to form the meshing of the other combination of teeth, and a large load is received by the pair of teeth, so that the strength is increased.

[Brief description of the drawings]

FIG. 1 is a side view of a seat provided with a reclining mechanism according to an example of the present invention.

FIG. 2 is a sectional view of a reclining mechanism.

FIG. 3 is a plan view showing meshing of inner and outer teeth.

FIG. 4 is a plan view showing another example of meshing of the internal and external teeth.

[Explanation of symbols]

 Reference Signs List 6 Reclining mechanism 7 Shaft 8 Eccentric shaft part 10, 10 'Upper arm 11, 11' Internal teeth 12, 12 'Concentric shaft part 14, 14' Lower arm 15, 15 'External teeth

Claims (2)

(57) [Claims] 1. A and upper arm of the pair having a support and an internal gear the seat back frame, internal gear of support and the upper arm of the seat cushion frame and each
A lower arm of the pair having a mesh Usotoha gear, a shaft having an eccentric shaft portion for supporting the Seikokorojiku receiving portion and the upper arm for supporting the Roaa <br/> beam, two pairs of mutually intermesh
The teeth of the external gear in the external gear and the internal gear
The number of teeth of the internal gear is smaller than the number of teeth of the internal gear;
The angle between the upper arm and the lower arm is adjusted by the rotation of
The seat reclining mechanism to be adjusted,
One is the backlash between the internal gear and the external gear, and the other is
From the backlash of the internal and external gears
To increase the size, shape the tooth profile differently
Seat reclining mechanism characterized by the following . 2. In one set of said internal gear and external gear
The backlash is the other pair of the internal gear and the external gear
0.1-0.2mm larger than the backlash of
2. The seat reclining mechanism according to claim 1 , wherein a tooth profile is formed .