Seat slide device for vehicles

1. A seat slide device for a vehicle, comprising:

a lower rail;

an upper rail slidably mounted on the lower rail; and

a lock mechanism for releasably locking the upper rail to the lower rail;

the lock mechanism including one or more locking fingers pivotally installed on an upper rail side and a plurality of engaged portions provided to a lower rail side;

wherein the one or more locking fingers are disposed within a space between the upper rail and the lower rail;

wherein the lock mechanism further includes a lock plate having the engaged portions, the lock plate being an independent part, disposed within the space and secured to the lower rail; and

wherein the lower rail is generally U-shaped in section and has a bottom wall and a pair of side walls, the lock plate being L-shaped in section and having a base wall attached to the bottom wall of the lower rail and a vertical wall having the engaged portions.

2. A seat slide device according to claim 1 , wherein the lock mechanism further comprises biasing means for urging the one or more locking fingers in the direction to engage a corresponding number of the engaged portions, the biasing means being disposed within the space.

3. A seat slide device according to claim 2 , wherein the lock mechanism further comprises a finger supporting plate for supporting the one or more locking fingers in case of engagement of the one or more locking fingers with the corresponding number of the engaged portions, the finger supporting plate being an independent part, disposed within the space and secured to the upper rail.

4. A seat slide device according to claim 3 , wherein the finger supporting plate comprises an integral bearing portion that pivotally supports the one or more locking fingers.

5. A seat slide device according to claim 3 , wherein the lock mechanism further comprises an additional finger supporting portion that is formed in the upper rail and supports the one or more locking fingers in case of engagement of the one or more locking fingers with the corresponding number of the engaged portions.

6. A seat slide device according to claim 4 , wherein the lock mechanism further comprises a support rod rotatably installed on the bearing portion of the finger supporting plate and a latch plate having the one or more locking fingers and installed on the support rod to swing together therewith, the support rod and the latch plate being disposed within the space.

7. A seat slide device according to claim 4 , wherein the upper rail is generally inverted U-shaped in section and has a top wall and a pair of side walls, the finger supporting plate being generally L-shaped in section and having a base wall attached to the top wall of the upper rail and a vertical wall having one or more support holes which correspond in number to the one or more locking fingers and in which the one or more locking fingers are engaged in case of engagement of the one or more locking fingers with the corresponding number of the engaged portions.

8. A seat slide device according to claim 5 , wherein the additional finger supporting portion of the lock mechanism comprises a recessed portion provided to one of the side walls of the upper rail, the recessed portion being recessed toward the vertical wall of the finger supporting plate and formed with one or more support holes which correspond in number to the one or more locking fingers and in which the one or more locking fingers are engaged in case of locking of the upper rail to the lower rail.

9. A seat slide device for a vehicle, comprising:

a lower rail adapted to be connected to a vehicle floor;

an upper rail adapted to carry a vehicle seat and slidably mounted on the lower rail; and

a lock mechanism for releasably locking the upper rail to the lower rail;

the lock mechanism including one or more locking fingers pivotally installed on an upper rail side, a plurality of engaged portions provided to a lower rail side and arranged in the longitudinal direction of the lower rail, a biasing unit for urging the one or more locking fingers in the direction to engage a corresponding number of the engaged portions;

wherein the one or more locking fingers and the biasing unit are disposed within a space between the upper rail and the lower rail;

wherein the lock mechanism further includes a lock plate having the engaged portions, the lock plate being an independent part, disposed within the space and secured to the lower rail, and

wherein the lower rail is generally U-shaped in section and has a bottom wall and a pair of guide walls, the lock plate being L-shaped in section and having a base wall attached to the bottom wall of the lower rail and a vertical wall having the engaged portions.

10. A seat slide device according to claim 9 , wherein the lock mechanism further comprises a finger supporting plate for supporting the one or more locking fingers in case of engagement of the one or more locking fingers with the corresponding number of the engaged portions, the finger supporting plate being an independent part, disposed within the space and secured to the upper rail.

11. A seat slide device according to claim 10 , wherein the finger supporting plate comprises an integral bearing portion that pivotally supports the one or more locking fingers.

12. A seat slide device according to claim 10 , wherein the lock mechanism further comprises an additional finger supporting portion that is formed in the upper rail and supports the one or more locking fingers in case of engagement of the one or more locking fingers with the corresponding number of the engaged portions.

13. A seat slide device according to claim 12 , wherein the engaged portions comprises engagement holes in which the one or more locking fingers are engaged in case of locking of the upper rail to the lower rail.

14. A seat slide device according to claim 13 , wherein the lock mechanism further comprises a support rod rotatably installed on the bearing portion of the finger supporting plate and a latch plate having the one or more locking fingers and installed on the support rod to swing together therewith, the support rod and the latch plate being disposed within the space.

15. A seat slide device according to claim 14 , wherein the upper rail is generally inverted U-shaped in section and has a top wall and a pair of side walls, the finger supporting plate being generally L-shaped in section and having a base wall attached to the top wall of the upper rail and a vertical wall having one or more support holes which correspond in number to the one or more locking fingers and in which the one or more locking fingers are engaged in case of engagement of the one or more locking fingers with the corresponding number of the engagement holes.

16. A seat slide device according to claim 9 , wherein the vertical wall of the lock plate is disposed adjacently opposite to the vertical wall of the finger supporting plate.

17. A seat slide device according to claim 11 , wherein the finger supporting plate comprises a base wall, and the bearing portion of the finger supporting plate comprises a pair of integral bent walls provided to opposite longitudinal ends of the base wall.

18. A seat slide device according to claim 12 , wherein the additional finger supporting portion of the lock mechanism comprises a recessed portion provided to one of the side walls of the upper rail, the recessed portion being recessed toward the vertical wall of the finger supporting plate and formed with one or more support holes which correspond in number to the one or more locking fingers and in which the one or more locking fingers are engaged in case of locking of the upper rail to the lower rail.