Vertically adjustable seat supports

摘要

The support is adjustable vertically in inclination and in height. It has a first lower rigid framework fast to the floor of the vehicle, a second rigid framework mounted pivotably around a horizontal axis connected to the first framework and extending over the width of the seat and a third rigid framework mounted pivotably around a second horizontal axis parallel to the first and connected to the second framework. First locking means actuate the locking and unlocking of the second framework in one or other of a plurality of its different angular positions of pivoting with respect to the first framework around the first axis, and second locking means actuate at will the locking and unlocking of the third framework in one or other of a plurality of its different angular positions of pivoting with respect to the second framework around the second axis. The first locking means are two gear sectors centred on the first axis and adapted to cooperate between themselves on locking, of which sectors one is fast to the first framework and of which the other is mounted on the second framework so as to be movable with respect to the first under the control of a rotary cam. The second locking means are also two gear sectors centred on the second axis and adapted to cooperate between themselves on locking, of which sectors one is fast to the third framework and of which the other is mounted on the second framework so as to be movable with respect to the first under the control of a second rotary cam. The two cams are constantly urged elastically towards their angular positions corresponding to locking, the gear sectors mounted on the second framework being constantly fast to the latter.