JPH0227810Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lumbar support adjustment device that is attached to a vehicle seat and that adjusts the amount of protrusion and pressing force of the seat back that contacts the lumbar region of the seat occupant to obtain an optimal seating posture. .

Generally, a lumbar support is adjusted by a lumbar plate pressing a cushion spring embedded in the pad of the seat back from the back side, and pushing out the pad near the lumbar region of the seat occupant along with the cushion spring. For this reason, an adjustment device is installed to adjust the amount of movement of the lumbar plate, but conventional adjustment devices are
As disclosed in the above publication, a lumbar plate is attached to the tip of a bent torsion spring, and the base end of the torsion spring is brought into contact with a cam that is rotated by a lever. The rotation of the lumbar plate moved the lumbar plate via a torsion spring. Although such an adjustment device has a simple structure and can be made into a unit, it has the disadvantage that the operating force is heavy when adjusting it with the back of a seated person pressed against it.
For this reason, as disclosed in Japanese Patent Application Laid-Open No. 173514/1983, an adjustment device was developed that included a ratchet and a cam to adjust the pressure applied to the torsion spring, thereby reducing the operating force. However, since it uses a ratchet, it can only be operated in one direction, and has the disadvantage that many operations are required to return the lumbar plate to its original position, and fine adjustments cannot be made.

The present invention solves these conventional drawbacks and provides a lumbar support adjustment device that reduces the operating force, allows both the strength and weakness of the pressing force to be adjusted, and allows fine adjustments to be made well. It is intended to. Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view of an embodiment of the present invention, in which a lumbar plate 2 is attached to the tip of a torsion spring 1. As shown in FIG. Although not shown, the lumbar plate 2 is embedded in a pad located in the lumbar region of the seat back and presses the lumbar region of the seated person from the back, and the pressing force is adjusted by the torsion spring 1. ing. This torsion spring 1 is bent as shown in the figure, and has a long arm part 1a on the distal end side and a short arm part 1b on the proximal end side, and the lumbar plate 2 is engaged with the long arm part 1a. It is worn. In addition, the short arm portion 1b is as described below.
The cam surface 3a of the cam member 3 comes into contact with the winding portion 1 between the short arm portion 1b and the long arm portion 1a.
c is formed, and the shaft 5 attached to the bracket 4 is inserted into this winding portion 1c.
A torsion spring 1 rotates around the shaft 5 in the longitudinal direction of the seat.
Such rotation of the torsion spring 1 is performed by the short arm portion 1b on the proximal end side coming into contact with the cam member 3, and the rotation of the cam member 3. Therefore, a slanted cam surface 3a that protrudes upward is formed on the surface of the torsion spring 1 that contacts the short arm portion 1b, and the contact with the cam surface 3a causes the torsion spring 1 to move. Rotates for fine adjustment. This cam member 3 is rotatably attached to a lid bracket 6 that fits into the bracket 4 by a pin 12, and the cam surface 3
A semi-disc-shaped driven gear 7 is attached to the opposite side of a to rotate integrally. Two mutually meshed lock gears 8 and 8' mesh with this driven gear 7, and the rotation of the cam member 3 is controlled by the meshing of the three gears consisting of these lock gears 8 and 8' and the driven gear 7. The rotation of the torsion spring 1 is thus locked. However, the rotation center shaft 13 of one of the lock gears 8' is inserted into the elongated hole 6a formed in the lid bracket 6.
By sliding the rotation center shaft 13 within the elongated hole 6a, it is disengaged from the driven gear 7 and the other lock gear 8, and the locked state is released. The rotation center shaft 14 of the other lock gear 8 is inserted into the mounting hole 6b of the bracket 4 and the lid bracket 6 so that it always meshes with the driven gear 7.
are meshing. The working gear 9 is fitted onto the tip of the working shaft 15 and rotates integrally with the rotation of the working shaft 15, but the working shaft 15 is opened at a position facing the bracket 4 and the lid bracket 6. By sliding the working shaft 15 in the long holes 4a and 6c, the working gear 9 maintains the meshing state with the other lock gear 8 and moves the center of rotation of the lock gear 8. axis 14
It is designed to move on an arc centered on . The rotation of the operating shaft 15 is performed by the seated person rotating a dial 16 that is fitted onto the base end and is prevented from coming off by a clip 17. Next, the one lock gear 8' is moved in the anti-meshing direction by rotating the working shaft 15, and for this purpose an engaging piece 10 is attached between the bracket 4 and the lid bracket 6. . This engagement piece 10 has a center portion through which the rotation center shaft 14 of the other lock gear 8 is inserted, and is configured to rotate left and right about the rotation center shaft 14, thereby controlling the rotation of the one lock gear 8'. central axis 1
3 is inserted into the lower part of the engaging piece 10, and the engaging piece 10 is rotated to move in the anti-meshing direction. The rotation of the engagement piece 10 is performed by the operating shaft 15 sliding and coming into contact with the upper end of the engagement piece 10. Furthermore, this engagement piece 10 has a rotation center shaft 1.
A return spring 14 inserted externally into the lock gear 4 is engaged, and the elastic force of the return spring 14 urges one lock gear 8' in the meshing direction.
Therefore, the lock gear 8' maintains a state in which it meshes with the driven gear 7 and the other lock gear 8 under normal conditions.

Next, the operation of the lumbar support adjusting device configured as above will be explained.

In FIG. 2A, when the load p of the lumbar plate 2 is applied, the cam surface 3a of the cam portion 3 that is in contact with the torsion spring 1 has the long arm portion 1a and the short arm portion 1b of the torsion spring 1. A load p' that increases in proportion to the arm length is applied, and a force acting on the cam member 3 to move it in the direction of arrow A as shown in FIG. Therefore, the cam member 3 is subjected to a rotational force in the direction of arrow A' shown in FIG. That is, in FIG. 3, a rotational force in the direction of arrow a is applied to the driven gear 7, a rotational force in the direction of arrow d is applied to one lock gear 8' meshed with this driven gear 7, and a rotational force in the direction of arrow d is applied to the other lock gear 8. A rotational force in direction b acts. Since the lock gears 8 and 8' are in mesh with each other, a rotational force in the direction of arrow c is applied from the other lock gear 8 to one lock gear 8'. Therefore, one lock gear 8'
is energized in the meshing direction between the driven gear 7 and the other lock gear 8 by the resultant force of the rotational forces c and d, thereby strengthening the meshing of the three gears, thereby locking the rotation of the driven gear 7, and the cam member 3 is locked. Therefore, even if the seated person's back presses against the lumbar plate, the lumbar plate does not move rearward and the lumbar support function can be maintained.

In order to push the lumbar plate 2 forward and increase the pressing force from the lumbar plate, the operating shaft 15 is rotated in the direction of arrow a, as shown in FIG. 4. With this rotation, the working gear 9 integrated with the working shaft 15 rotates in the same direction, causing the other lock gear 8 to rotate in the direction of arrow b, applying a rotational force in the direction of arrow c to the driven gear 7, and also rotating the other lock gear 8 in the direction of arrow c. 8′
The rotational force in the direction of arrow d is transmitted to. On the other hand, since a rotational force in the direction of arrow e is applied from the driven gear 7 to one of the lock gears 8', one of the lock gears 8' moves in the direction shown by the arrow B by the resultant force of the rotational forces d and e, and the driven gear 7 and the other lock gear 8 are disengaged from each other. As a result, the locked state caused by the meshing of the three gears is released, and the driven gear 7 is moved to the position indicated by the arrow C.
The cam member 3 also rotates integrally in the same direction, and the lumbar plate 2 advances forward via the torsion spring 1, thereby strengthening the supporting force.

Next, when the lumbar plate 2 is to be moved backward, this is done by rotating the operating shaft 15 in the opposite direction. This rotational force causes the operating shaft 15 to move in the direction of arrow D as shown in FIG.
0, presses the engagement piece 10 in the same direction, and rotates the engagement piece 10 clockwise. With this rotation, one of the lock gears 8', the rotational center shaft 13 of which is attached to the lower end of the engagement piece 10, moves in the direction of arrow E and is released from the meshed state. Therefore, the locked state is released, and the rotation in the direction of arrow a' transmitted from the working shaft 15 to the working gear 9 is transferred to the other lock gear 8.
The driven gear 7 is rotated in the direction of arrow b′ of
By rotating in the c' direction, the lumbar plate 2 can be moved backward via the cam member 3 and the torsion spring 1, thereby weakening the supporting force.

According to the present invention explained above, since the pressing force of the lumbar plate is adjusted by the meshing of the lock gear and the driven gear, it is possible to reduce the operating force, and the amount of adjustment can be made by changing the number of teeth of the gear. can be subdivided and fine-tuned. Further, since the supporting force of the lumbar plate can be adjusted in both directions by simply changing the direction of rotation of the operating shaft, the operation is simplified and easier to operate.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of one embodiment of the present invention;
Figures A to C are plan views, schematic diagrams, and perspective views of the main parts to explain the operation, and Figure 3 is an operation diagram in the locked state.
FIGS. 4 and 5 are operational diagrams of the adjustment state. 1... Torsion spring, 2... Lumbar plate, 3... Cam member, 3a... Cam surface, 4
... Bracket, 7... Driven gear, 8, 8'...
Lock gear, 9... Working gear, 10... Engaging piece,
15... Axis of action.

Claims (1)

[Scope of utility model registration request] a torsion spring having a lumbar plate attached to its distal end and applying a pressing force to the plate; a bracket rotatably supporting the proximal end of the torsion spring; a cam member formed with an engaging inclined cam surface and to which a driven gear is integrally attached; two lock gears disposed at positions that mesh with the driven gears and mesh with each other; A working shaft that is inserted through the bracket and has a working gear attached thereto that meshes with the other lock gear of the lock gears, and a contact portion that has one lock gear of the lock gears attached to one end and that comes into contact with the working shaft on the other end. and an engaging piece that urges the one lock gear in the meshing direction with a spring force, and locks the lumbar plate by meshing the two lock gears with the driven gear, and also locks the one of the operating shafts. By rotating in the direction, the operating shaft presses the abutting part of the engagement piece to rotate the engagement piece, and at the same time moves one lock gear in the anti-meshing direction to release the lock, and rotates the operating shaft in the other direction. Adjust the position of the lumbar plate by rotating the other lock gear and the driven gear via the working gear and moving the one lock gear in the anti-meshing direction to release the meshing between the one lock gear and the driven gear. A lumbar support adjustment device featuring: