JPH0450844Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a lumbar support adjustment device provided in a seat of a vehicle or the like.

[Conventional technology]

Vehicle seats, especially passenger car driver seats,
2. Description of the Related Art Seats equipped with a lumbar support adjustment device (lumbar support device) that variably adjusts the support pressure of the lumbar region are widely used so that a seated person can enjoy a comfortable sitting feeling.

As a conventional lumbar support adjustment device of this type, there is one described, for example, in Japanese Patent Publication No. 16786/1986.

That is, this lumbar support adjustment device is equipped with a polygonal cam connected to a control lever as a movement adjustment mechanism for a lumbar support member (lumbar plate) that supports the lumbar region of a seated person. By rotating the lumbar vertebra support member, the forward and backward movement position, that is, the amount of extrusion, of the lumbar vertebra support member is adjusted by pressure, and thereby the strength of the support pressure on the seated person is adjusted in stages.

[The problem that the idea aims to solve]

Such conventional lumbar support adjustment devices are configured to adjust the support pressure in stages using polygonal cams, so it is not possible to make fine adjustments to suit the preferences of the seated person. Moreover, this conventional device has a structure in which the cam is rotated directly by an operating lever, so a large operating force is required for its operation, which also has drawbacks in terms of operability. .

The present invention has been developed in view of the above, and an object of the present invention is to provide a lumbar support adjustment device that can be adjusted to suit the preferences of a seated person and has good operability.

[Means to solve the problem]

In order to achieve the above-mentioned object, the lumbar support adjustment device of the present invention includes an arm that is pivotally supported on a seatback frame so as to be rotatable in the front and back direction, and that supports a lumbar support member at its free end, and a proximal end of this arm. A lumbar support member is interposed between the sub-arm and the arm to urge the lumbar support member forward. a spring that applies a rotational biasing force to the arm so that the arm is rotated, a brake device that is fixed to the seat back frame side and rotates the drive shaft only when rotation is operated from the operating shaft side, and a shaft attached to the seat back frame side. The cam is supported by a disc-shaped cam whose circumferential surface is in contact with the free end of the sub-arm, and which is rotatably connected to the drive shaft of the brake device via a gear mechanism.

[Effect]

The measures described above operate as follows.

When the operating shaft of the brake device is operated to rotate the drive shaft, this rotation is transmitted to the cam via the gear mechanism, causing the cam to rotate. The rotation of this cam continuously presses the free end of the sub-arm,
This compresses the spring and changes its elasticity. Therefore, the rotational biasing force applied to the arm changes, thereby variably adjusting the support pressure of the lumbar support member. In this support pressure adjustment operation,
Since the sub-arm is continuously pressed by the disc-shaped cam, the support pressure of the lumbar support member is adjusted steplessly.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, 1 indicates a vehicle seat, and this seat 1
A plate-shaped lumbar support member 3 is built into the seat back 2 at a portion corresponding to the lumbar region of the seated person, and by variably adjusting the amount of extrusion of this lumbar support member 3, the support pressure for the seated person is adjusted. .

Reference numeral 4 denotes a seat bag frame forming the skeleton of the seat bag 2. An arm 6 is rotatably supported in the front and rear direction by a support shaft 7 on a bracket 5 fixed to one side of the seat bag frame 4. There is. The arm 6 is bent into an F-shape at approximately the center so that the free end faces forward, and the lumbar support member 3 is engaged at the tip of the arm 6 at an engagement portion 3a formed at the center of the back surface. Supported.

Further, the proximal end portion of the arm 6 is formed with an extended projecting surface portion 6a that extends in the opposite direction to the free end portion across the shaft support relative to the bracket 5.

Further, on the bracket 5, a sub-arm 8 extending in such a manner as to face the extended protruding surface portion 6a of the arm 6 in the front-rear direction is supported by a support shaft 7 in the same manner as the arm 6 so as to be rotatable in the front-rear direction.

A pair of compression coil springs 9 are provided between the sub-arm 8 and the extended protruding surface portion 6a of the arm 6.
is interposed, and this compression coil spring 9
Due to the elastic repulsive force of the arm 6, the arm 6 is biased so that its free end rotates forward (in the direction of arrow a), so that the lumbar support member is always urged forward and its front surface is biased. It presses the seat pad placed on the seat.

In order to prevent the compression coil spring 9 from falling off, bosses 10a and 10 are provided on opposing surfaces of the sub-arm 8 and the extended protruding surface portion 6a of the arm 6, respectively.
b is formed and engages the compression coil spring 9.

The bracket 5 is provided with an adjustment mechanism for changing the elastic repulsive force of the compression coil spring 9 and adjusting the amount of extrusion of the lumbar support member 3.

This adjustment mechanism is constructed as follows.

A shaft 11 is provided on the bracket 5 and extends inward so as to correspond to the sub-arm 8.
A cam 12 is pivotally supported. Note that the inner end of the shaft 11 is connected to a support plate 13 fixed to the bracket 5.
Supported by.

The cam 12 is a disc-shaped cam made of an eccentric disc body having an eccentric cam surface 12a continuous over its entire circumferential surface. It is in contact with the surface on the opposite side to the side to which it is applied. In this example, in order to reduce the rotational and sliding resistance of the cam 12,
A protrusion 8a is formed at the center of the front surface of the sub-arm 8, and a cam 12 is brought into point contact with this protrusion 8a.

Also, this cam 12 is provided on the outer surface of the bracket 5.
A brake device 14 for rotating and locking is fixed.

This brake device 14 has the same configuration as a friction brake device employed as a wind regulator of an automobile, for example, and although the detailed structure will be described later, an operating shaft 1 is provided on the outer side.
5. The drive shaft 16 is protruded inward, and even if a rotational force is applied to the drive shaft 16, the drive shaft 16 is prevented from rotating, and only when the operation shaft 15 is rotated, The drive shaft 16 operates as if it were rotated.

A handle 17 is attached to an operating shaft 15 of the brake device 14, and a drive shaft 16 passes through a hole in the bracket 5, and a drive gear 18 is fixed to the tip thereof. On the other hand, the cam 12 has a driven gear 1 which has more teeth than the drive gear 18.
9 is integrally formed, and a drive gear 18 is meshed with this driven gear 19.

As a result, the drive shaft 16 of the brake device 14
The rotation of the cam 12 is reduced in speed and transmitted to the cam 12 via a gear mechanism consisting of a drive gear 18 and a driven gear 19 having a larger number of teeth than the drive gear 18.

Next, the configuration of the brake device 14 mentioned above will be explained with reference to FIGS. 6 and 7. This brake device 14 has a torsion coil spring 22 formed with locking portions 22a and 22b at both ends in close pressure contact with the inner periphery of a circular outer case 21, and a locking portion 22a of the torsion coil spring 22 on the outer periphery thereof. and 22
Insert the inner circular case 23 formed with engagement edges 23a and 23b corresponding to b, and insert the inner circular case 23.
The operating shaft 15 is fixed to the outer surface of the outer case 2.
It is made to protrude outward from the shaft hole 21a of No. 1. A shaft 24 is fixed to the center of the inner surface of the inner case 23 of this brake mechanism, that is, aligned with the axial direction of the operating shaft 15.

This shaft 24 has a drive shaft 1 that protrudes inward.
The drive shaft 16 has an arm 16a located between the locking portions 22a and 22b of the torsion coil spring 22 in the inner case 23.
will be established. In the brake mechanism configured as described above, when the operating shaft 15 is rotated, for example, in the direction of the arrow in FIG. By further rotating the operating shaft 15 in this state, the torsion coil spring 22 is contracted and separated from the inner peripheral surface of the outer case 21, and the operating shaft 15 can freely rotate in the direction of the arrow. The drive shaft 1 is connected to the shaft 15 via the inner case 23 and the arm 16a.
6 is rotated.

When the rotation of the operating shaft 15 is thus stopped at the desired rotational position, the torsion coil spring 22 is released from the pressure exerted by the inner case 23, so that it returns to its original state and comes into tight pressure contact with the inner peripheral surface of the outer case. When an unexpected rotational force is applied to the drive shaft 16 in this state, the arm 16a comes into contact with the locking part 22a or 22b of the torsion coil spring 22 corresponding to the direction of rotation of the arm 16a, presses this, and spreads the torsion coil spring 22. As a result, the frictional force between the torsion coil spring 22 and the outer case 21 is further strengthened, and the rotation of the drive shaft 16 is thus prevented.

In the lumbar support adjustment device of this example configured as described above, when an occupant sits on the seat 1, the lumbar region of the occupant is supported by the lumbar support member 3, and at this time, the compressed coil spring 9 is By being compressed, the elastic repulsion force imparts appropriate elasticity to the lumbar support member 3, so that the lumbar region of the seated person is suitably supported.

and the brake device 14 by the handle 17.
When the drive shaft 16 is rotated by rotating the operating shaft 15 of the cam 12, this rotation is decelerated and transmitted to the cam 12 via the drive gear 18 and the driven gear 19.
Cam 12 is rotated. When the cam 12 is rotated in this manner, the free end of the sub-arm 8 is pressed due to continuous changes in the cam surface 12a, and the compression coil spring 9 is further compressed. Therefore, the elastic repulsive force of the compression coil spring 9 increases and acts to further rotate and bias the free end of the arm 6 forward, that is, the lumbar support member 3 is pushed forward to support the lumbar region of the seated person. The pressure gets stronger.

Further, in this example, since the cam surface 12a of the cam 12 is formed continuously through 360 degrees, by continuously rotating the handle 17 in the same direction, the pressure on the sub-arm 8 is reduced, thereby reducing the pressure on the lumbar support member. The support pressure according to No. 3 is set to the original state.

When the support pressure of the lumbar vertebrae is adjusted to the desired strength, the rotation of the handle 17 is stopped, and the cam 12 is locked in a non-rotatable manner by the action of the brake device 14 as described above. The supporting pressure of the part is held fixed by its strength.

In the above adjustment operation, the brake device 14
The rotation of the drive shaft 16 is transmitted to the cam 12 via the drive gear 18 and the driven gear 19 which has more teeth than the drive gear 18. Although the rotational force on the shaft 16 side is small, it can sufficiently rotate the cam 12 and press the sub-arm 8, that is, the handle 1
7 does not require much force to operate, so its operability is extremely good.

[Effect of idea]

As described above, the lumbar support adjustment device of the present invention continuously changes the elasticity of the spring by rotating the cam via the brake device, thereby adjusting the amount of extrusion of the lumbar support member in a stepless manner. The support pressure of the lumbar vertebrae can be finely adjusted according to the preferences of the seated person, and the device of the present invention is configured to transmit the rotation of the drive shaft of the brake device to the cam via a gear mechanism. Therefore, by selecting an appropriate gear ratio for each gear of this gear mechanism, adjustment can be made with a small operating force, and operability is improved, which has greater practical effects than before.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the device of the present invention seen from below, Figure 2 is a perspective view of a seat equipped with the device of the present invention, Figure 3 is a perspective view of its frame structure, and Figure 4 is a view of the device of the present invention. 5 is an exploded perspective view of the same, FIG. 6 is an exploded perspective view of the brake device, and FIG. 7 is an inner side view of the same. In the figure, 3 is a lumbar support member, 4 is a seatback frame, 5 is a bracket, 6 is an arm, 8 is a sub-arm, 9 is a compression coil spring, 12 is a cam, 14 is a brake device, 15 is its operating shaft, 1
6 is a drive shaft, 18 is a drive gear, and 19 is a driven gear.

Claims (1)

[Scope of Claim for Utility Model Registration] An arm that is pivotally supported by the seat back frame so as to be rotatable in the front-back direction and supports a lumbar support member at its free end; a sub-arm provided on the seatback frame and rotatably supported in the front-rear direction; and a sub-arm interposed between the sub-arm and the arm so as to urge the lumbar support member forward. a spring that applies a rotational biasing force to the arm; a brake device that is fixed to the seat back frame side and rotates the drive shaft only when a rotation operation is performed from the operating shaft side; and a brake device that is pivotally supported on the seat back frame side. , a disc-shaped cam whose circumferential surface abuts the free end of the sub-arm and is rotatably connected to the drive shaft of the brake device via a gear mechanism, the disc The lumbar support adjustment is characterized in that the support pressure of the lumbar support member is adjusted in a stepless manner by continuously pressing the sub-arm and changing the elasticity of the spring by rotating the shaped cam. Device.