JPH0117006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stepless angle adjustment mechanism used in reclining seats, headrests, seat lifters, etc.

Conventional reclining mechanisms are constructed by providing a sector gear on one bracket of the bottom and backrest, and a lock gear on the other bracket, and adjust the angle of the backrest by engaging and disengaging these gears. was. However, reclining mechanisms that use such gears cannot change the adjustment angle steplessly, and in order to increase the number of steps of adjustment angle and make it as close to stepless as possible, the gear teeth must be formed finely. There was a problem that this resulted in a lack of strength.

In view of the above-mentioned problems, the present invention aims to provide an angle adjustment mechanism that allows stepless adjustment with a simple mechanism.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, S indicates a seat portion of a reclining seat as a fixed portion, and B indicates a backrest as a movable portion whose angle is to be adjusted. The seat S has a bracket 2 on at least one side thereof, and the backrest has a bracket 3 on at least one side thereof.
are each fixed. As shown in FIG. 2, a disk 4 having a cylindrical peripheral surface with a radius r is fixed to the bracket 2 of the seat, and this disk 4 projects toward the front in FIG.
A concentric shaft hole 5 is formed in the center of the disk 4. 6 is an eccentric ring, the radius of its outer peripheral surface is R, and the thickness in the radial direction is t. The inner diameter R-t of this eccentric ring 6 is larger than the radius r of the disk 4. In the assembled state, this eccentric ring 6 is attached to the disk 4 as shown in FIG.
applied to the outer circumferential surface of the In this state, the inner circumferential surface of the eccentric ring 6 contacts a part of the outer circumferential surface of the disk 4 in a freely rolling manner. As is clear from FIG. 3, the center of the eccentric ring 6 is eccentric downwardly from the center of the disk 4 by an amount e.

As shown in FIG. 2, the backrest bracket 3 has a shaft hole 7 that matches the shaft hole 5 of the bracket 2, and both brackets 2 and 3 have an eccentric ring 6 sandwiched between them. The shafts 8 and 7 are opposed to each other, and are pivotably connected to each other by inserting shafts 8 through both shaft holes 5 and 7. The head 8a of the shaft 8 comes into contact with the outer surface of the bracket 3 during assembly, and the tip of the shaft 8 is made to protrude toward the rear side of the bracket 2 in FIG. 2, into which a nut 10 is screwed.

Backrest bracket 3, seat bracket 2
A circumscribing member 11 is provided in a protruding manner on the surface facing the . This circumscribing member is integrally joined to the surface of the bracket 3 at surfaces 11a, 11a, and has a cutout portion 11b in the middle thereof, from which a pin 12 is protruded. The lower surface of the circumscribing member 11 in the drawing is formed as a contact surface 13 (FIG. 3), which has the same center as the center of the eccentric ring 6 and a radius of the outer peripheral surface of the eccentric ring 6. R
has the same radius as. Further, the center portion 15 of the contact surface 13 is located at a distance r+t from the center of the disk 4 in the assembled state, and therefore the eccentric ring 6
The inner circumferential surface thereof contacts the outer circumferential surface of the disk 4 at a point (line) 16, and the outer circumferential surface thereof comes into close surface contact with the contact surface 13 of the circumscribing member 11. In addition,
The contact surface 13 may omit an arcuate surface portion in the middle thereof, or may be a non-arc surface with only both ends in contact with the outer surface of the eccentric ring 6.

In the state shown in FIG. 3, if by displacing the backrest in either direction, the bracket 3 is rotated in the same direction, the circumscribing member 11 also moves in the same direction, as shown in FIG. 4, for example. At this time, the eccentric ring 6 rolls on the outer circumferential surface of the disk 4 while a part of its outer circumferential surface is in surface contact with the contact surface 13 of the circumscribing member 11 . However, assuming that the eccentric ring 6 is fixed to the disk 4 in a non-rollable manner at any rotational position, the circumscribed member 11
It quickly becomes impossible to move. This is because, as shown in FIG. 3, the locus of movement of both ends of the contact surface 13 of the circumscribed member 11 is a locus 13x along an arc around the center of the disk 4 (the center of the axis 8), and this locus is This is because 13x extends in the direction of biting into the eccentric ring 6. The fact that the circumscribing member 11 cannot be displaced in this way means that the backrest B is also fixed in an immovable state.

The above is the basic principle of the present invention, but in order to fix the eccentric ring 6 to the disk 4 so that it cannot roll, for example, the following means can be used.

In FIG. 1, 20 is an eccentric ring fixing member, the overall shape of which is as shown in FIG. However, in the case of FIG. 1 and the case of FIG. 5, the eccentric ring fixing member 20 is shown upside down. The eccentric ring fixing member 20 has a long hole 21 at its tip, a large long hole 22 in the middle, and a contact portion 23 for contacting the inner peripheral surface of the eccentric ring at its base. The tip of the eccentric ring fixing member 20 is inserted into the cutout 11b of the circumscribing member 11, and the pin 12 is engaged in the elongated hole 21. Further, the aforementioned shaft 8 is inserted through the long hole 22 located in the middle. The abutting part 23 is a protruding part that is thicker than the main body of the eccentric ring fixing member 20, and as shown in FIG. It is formed in a shape that can make surface contact with the inner circumferential surface of the ring 6, and is usually in contact with the inner circumferential surface of the eccentric ring 6. The eccentric ring fixing member 20 can be displaced in the vertical direction by being guided by the pin 12 and shaft 8 described above.

In FIG. 2, 27 is an operating lever, and a shaft hole 28 is formed at its tip. This shaft hole 2
A shaft 8 is inserted through the shaft 8, and the operating lever 27 is rotatable around the shaft 8. A pin 29 is formed in the bracket 3 of the backrest B, and a tension spring 31 is stretched between the pin 29 and the lug 30 of the operating lever 27, so that the operating lever 27 can be moved as shown in FIG. In FIG. 6, a force is applied to rotate clockwise. As shown in FIG. 2, the lower end of the operating lever 27 has a pressing inclined surface 3.
3 is formed. When the operating lever 27 is operated in a counterclockwise direction as shown in FIG. The lower surface 25 of the contact portion 23 does not particularly act on the eccentric ring 6, but when you release your hand from the operating lever 27, the operating lever 27 rotates clockwise due to the force of the spring 31, as shown in FIG. As shown in the contact part 2
The operating lever 27 is pressed against the inclined surface 24 of 3.
3 is pressed together. This pressing force presses the lower surface 25 of the contact portion 23 against the inner circumferential surface of the eccentric ring 6, and the eccentric ring 6 becomes unable to roll around the disk 4 due to this pressing action. Therefore, the backrest bracket 3 becomes immovable, and the inclination of the backrest is fixed.

To change the inclination of the backrest, press operation lever 2.
7 against the force of the spring 31 to obtain the state shown in FIG. 6, the backrest is set at an appropriate angle, and then the operating lever 27 is released and the backrest is fixed at the new angle.

As described above, according to the present invention, the eccentric ring that is hung on the disk on one side of the fixed part and the movable part and rolls around it cannot be displaced relative to the disk. On the other hand, the inclination angle of the other side having the circumscribed member that is relatively immovable can be easily adjusted and fixed in a stepless manner.

Moreover, since the fixing force between the disk and the eccentric ring is released by operating the operating lever, the fixing force can be easily released with a small operating force.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of the first embodiment of the present invention, Fig. 2 is an exploded perspective view of the same, Fig. 3 is a diagram of the same principle,
Fig. 4 is a principle diagram similar to Fig. 3 in different tilted states, Fig. 5 is a perspective view of the eccentric ring fixing member,
FIG. 6 is a partially cutaway side view similar to FIG. 1 showing the state when the operating lever is operated. S... Fixed part (bottom) B... Movable part (backrest), 2, 3... Bracket, 4... Disc,
6... Eccentric ring, 8... Shaft, 11... Circumscribed member, 11b... Resection part, 12... Pin, 13...
Contact surface, 20... Eccentric ring fixing member, 23...
Contact portion, 24... inclined surface, 25... lower surface, 27...
...Operation lever, 33... Pressing inclined surface.

Claims (1)

[Claims] 1. A disk fixed to at least one side of the fixed part and the movable part whose angle is to be adjusted so as to have a transverse axis, and a part of the outer circumferential surface of the disk, which has an inner diameter larger than the diameter of the disk. An eccentric ring is positioned on the outside of the disk with its inner circumferential surface in contact with the disk in a rolling manner, and an eccentric ring is placed on the outer circumferential surface of the ring at a position facing the disk with the ring in between in the radial direction. and around the lateral axis of the disk,
a circumscribing member fixed to the other side of the fixed part and the movable part pivotally connected to the one side of the fixed part and the movable part; and an eccentric that is diametrically opposed to the contact position of the eccentric ring with respect to the outer peripheral surface of the disk. an eccentric ring fixing member having an abutting portion that can press the inner circumferential surface of the ring from the inside in the radial direction; A stepless angle adjustment mechanism including an operating lever having a press-contact inclined surface that can freely engage with an inclined surface of a member.