JPH09262154A - Lumber supporting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent rattling of a torsion bar in the direction across the width of a seat back. SOLUTION: A lumber support device has a flange-shaped mounting wall 73 which is formed on a movable member 7, protrudes in the direction across the seat back, and is positioned approx. parallel with a torsion bar 3. A detaining hole 73a is formed in the mounting wall 73 in such a way as penetrating the width of the seat back, and a bend part 36 is formed at one end 32 of the torsion bar 3, bent in the direction across the thickness of the seat back, and inserted into and detained by the hole 73a from the direction across the thickness of the seat back.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lumbar support device for supporting the lumbar region of a seated person and adjusting its supporting force to a desired state.

[0002]

2. Description of the Related Art Conventionally, as this type of lumbar support device, the one disclosed in Japanese Patent Laid-Open No. 6-165718 has been known. This is a movable member that is inserted in one of the pair of side frames that are arranged to face each other in substantially parallel in the seat back width direction and is rotatably supported by being inserted from the seat back width direction, and has one end linked to the movable member and the other. It is configured to have a crank-shaped torsion bar in which an end is rotatably supported by the other of the pair of side frames and is arranged between the pair of side frames, and the seat is seated at the pressure portion. The waist of the person is supported, and the pressure bar is moved in the thickness direction of the seat back by rotating the torch bar by the rotation of the movable member, thereby providing a support force for supporting the waist of the seated person. I was adjusting.

Further, in this conventional apparatus, one end of the torsion bar is inserted through one of the side frames in the seat back width direction, and is retained and locked by caulking or the like.

[0004]

However, in the conventional device described above, one end of the torsion bar is inserted from the seat back width direction and is locked to one of the side frames, like the other end. The bar easily rattles in the width direction of the seat back, and this rattling may cause the other end of the torsion bar to come off the side frame.

Further, in order to prevent the rattling of the torsion bar in the seat back width direction, one end of the torsion bar may be fixed to the side frame by welding or the like. This will lead to an increase.

Therefore, it is a technical object of the present invention to prevent rattling of the torsion bar in the seat back width direction.

[0007]

The technical means taken in the present invention in order to solve the above technical problems is a flange-shaped member formed on a movable member and protruding in the seat back width direction and being substantially parallel to the torsion bar. A mounting wall, a locking hole formed in the mounting wall and penetrating in the seat back thickness direction, a bending hole formed in one end of the torsion bar in the seat back thickness direction, and inserted into the locking hole from the seat back thickness direction. And a bent portion to be stopped.

According to this technical means, the torsion bar is restricted in the seat back width direction by the mounting wall of the movable member by inserting the bending portion of the torsion bar into the locking hole of the movable member from the seat back thickness direction. To be done. Therefore, rattling of the torsion bar in the seat back width direction can be prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS.
A torsion bar 3 having a pressurizing portion 31 for supporting the lumbar region of a seated person is formed inside the seat back 1 so as to face each other substantially in parallel in the seat back width direction (left and right direction in FIG. 1 and paper surface direction in FIG. 2). The pair of side frames 4 and 5 which are components of the seat back 1 are rotatably supported at one end 32 and the other end 33 thereof.

The torsion bar 3 has a crank shape in which arm portions 34 and 35 which are continuous from both ends 31a and 31b of the pressing portion 31 to one end 32 and the other end 33 are formed. As a result, as the torsion bar 3 rotates, the pressing portion 31 moves in the sheet back thickness direction (the paper surface direction in FIG. 1 and the left and right direction in FIG. 2). In addition, a support member 2 is attached to the pressurizing portion 31 for facilitating support of a seated person's waist or the like.

A bracket 6 is fixed to the side frame 4 at an appropriate position in the vertical direction of the seat back (vertical direction in FIGS. 1 and 2). A sector gear 7 is rotatably supported by a pin 8 on the bracket 6. As a result, the sector gear 7 is rotatably supported by the side frame 6. A well-known brake mechanism 9 such as a well-known spring coupler device is attached to the bracket 6, and the seat back 1 is attached to its input shaft 9a.
The handle 91 arranged on the side of the output shaft 9 is fixed.
A pinion gear 92 meshing with the sector gear 7 is fixed to b.

As shown in FIGS. 1 to 4, the sector gear 7 is made of a single plate material and is arranged such that the plate thickness direction is the seat back width direction. Further, at the lower end of the sector gear 7, the tooth portion 7 that meshes with the pinion gear 92 is provided.
1 is formed, and a through hole 72 through which the pin 8 is inserted is formed in the center. Further, at the upper end of the sector gear 7, there is formed a mounting wall 73 which is continuously bent from the side edge on the rear side in the seat back thickness direction. The mounting wall 73 has a flange shape that protrudes in the seat back width direction and is substantially parallel to the torsion bar 3, and has a locking portion 36a, which will be described later and penetrates in the seat back thickness direction.
A circular locking hole 73a through which the locking hole 36a can be inserted and a cutout hole 73b into which a locking portion 36b described later can be fitted are formed in the lower part.

As shown in FIGS. 1 to 4, in the seat thickness direction, a pair of substantially parallel locking portions 36a and 36b extending in the seat thickness direction are formed at one end 32 of the torsion bar 3. A bent U-shaped bent portion 36 is formed. The locking portion 36a of the bent portion 36 has substantially the same diameter as the locking hole 73a, and the locking portion 36b has substantially the same diameter as the cutout hole 73b. Further, in the bent portion 36, the locking portion 36b is fitted in the cutout hole 73b and the locking portion 36a is locked in the locking hole 73b.
It is inserted into the seat back from the thickness direction of the seat back, and further, the tip of the engaging portion 36a, that is, the one end 32 of the torsion bar 3 is caulked and prevented from coming off, so that it is engaged with the mounting wall 73. As a result, the one end 32 of the torsion bar 3
Will be linked to the sector gear 7. Notch hole 7
A protrusion 73c is formed at the opening edge of 3b, which makes it difficult to pull out the locking portion 36b from the cutout hole 73b.

As shown in FIG. 1, the side frame 5
Has a through hole 51 formed coaxially with the pin 8. The other end 33 of the torsion bar 3 has the through hole 5
1 is inserted from the seat back width direction. As a result, the other end of the torsion bar 3 is rotatably supported by the side frame 5.

Next, the assembling of the lumbar support device constructed as described above to the side frames 4 and 5 will be described.

First, the bracket 6 supporting the brake mechanism 9 and the sector gear 7 is attached to the input shaft 9a of the brake mechanism 9.
Is attached to the side frame 4 so as to be inserted into the through hole 41 formed in the side frame 4. Next, the other end 31 of the torsion bar 3 to which the support member 2 is attached
Through the through hole 51 of the side frame 5, and then, while fitting the locking portion 36b of the bent portion 36 into the cutout hole 73b, twist the bent portion 36 to lock the locking portion 36a of the bent portion 36. 73a is inserted from the sheet thickness direction. And finally,
The tip of the locking portion 36a is caulked. As a result, the assembling of the lumbar support device to the side frames 4 and 5 is completed. In this state, the torsion bar 3 has the locking portion 36.
The engagement wall 73 of the sector gear 7 is engaged with the engagement hole 73a
Due to this, movement in the axial direction in the seat back width direction is restricted. As a result, rattling of the torsion bar 3 in the seaback width direction is prevented. The rattling of the torsion bar 3 in the seat back thickness direction is suppressed by the load applied to the torsion bar 3 by the seated person.

Next, the operation of the lumbar support device will be described.

In FIG. 1, when the handle 91 is rotated in one direction to rotate the pinion gear 92 via the brake mechanism 9, the sector gear 7 rotates about the pin 8. As a result, the torsion bar 3 rotates in one direction with the axis passing through the pin 8 and the through hole 51 (the other end 33 of the torsion bar 3) as the center of rotation, and the pressing portion 31 moves to the front side of the seat back in the thickness direction of the seat back. As a result, the support force for supporting the waist and the like of the seated person is adjusted to a desired state by the pressing portion 31. Incidentally, by rotating the handle 91 in the opposite direction to the above, the torsion bar 3 can be rotated.
The pressure portion 31 of moves to the rear side of the seat back in the seat back thickness direction.

As shown in FIGS. 5 and 6, the cutout hole 73b of the mounting wall 73 of the sector gear 7 may be an elongated hole 73d. In this case, the protrusion 73c becomes unnecessary. The long hole 7
3d is a locking portion 36a of the bent portion 36 of the torsion bar 3.
The size is large enough to allow the bending portion 36 to be twisted when the locking portion is locked in the locking hole 73a.

[0020]

According to the present invention, the movable member is provided with a flange-shaped mounting wall that projects in the seat back width direction and is substantially parallel to the torsion bar, and penetrates in the seat back thickness direction formed on the mounting wall. Since the bent portion formed at one end of the torsion bar is inserted and locked in the locking hole from the seat back thickness direction, the torsion bar can be restricted in the seat back width direction by the mounting wall of the movable member. It is possible to prevent rattling of the bar in the seat back width direction. Further, since the rattling of the torsion bar in the seat back width direction is prevented by inserting and locking the bent portion into the locking hole, welding or the like is unnecessary and the assembling property can be greatly improved.

[Brief description of drawings]

FIG. 1 is a plan view of a lumbar support device according to the present invention in an assembled state on a side frame.

FIG. 2 is a side view of the lumbar support device according to the present invention.

FIG. 3 is a plan view showing a state where one end of a torsion bar of the lumbar support device according to the present invention is linked to a movable member.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a plan view showing a modified example of the state in which one end of the torsion bar of the lumbar support device according to the present invention is linked to the movable member.

FIG. 6 is a side view of FIG. 5;

[Explanation of symbols]

 3 torsion bar 4,5 side frame 7 sector gear (movable member) 36 bent portion 73 mounting wall 73a locking hole

Claims (1)

[Claims] 1. A movable member rotatably supported by one of a pair of side frames arranged to face each other in a direction substantially parallel to the seat back width direction, one end of which is linked to the movable member and the other end of which is a pair of the movable member. The other side frame includes a crank-shaped torsion bar that is rotatably supported by being inserted in the seat back width direction and is disposed between the pair of side frames, and has a crank-shaped torsion bar. In a lumbar support device in which the pressing portion is moved in the seat back thickness direction by rotating the torsion bar by a dynamic operation, the lumbar support device is formed on the movable member and protrudes in the seat back width direction and is substantially parallel to the torsion bar. A flange-shaped mounting wall, a locking hole formed in the mounting wall and penetrating in the seat back thickness direction, and formed in one end of the torsion bar. A lumbar support device having a bent portion that is bent in the seat back thickness direction and is inserted and locked in the locking hole from the seat back thickness direction.