Abstract: Shock absorber (31) for a hydropneumatic vehicle suspension element, comprising a disk (32) fastened in an outer casing having ports (30, 38) for the passage of the hydraulic fluid, first elements (48, 49, 37a, 37b) allowing this passage in only one direction for some ports (30) and in the opposite direction for the other ports (38), and second elements (53, 54, 55) for fastening the first elements to the disk; the abovementioned first elements comprise, mounted on the two opposite faces of the disk (32), stacks (46, 47) of elastically flexible metal washers (46a-46c; 47a-47c) arranged in rigid annular deflectors (48, 49) located opposite the hydraulic-fluid passage ports (30, 38). The deflectors protect the flexible washers against any damage caused by the very high peaks of hydraulic pressure which occur on uneven ground.

Abstract: The hydropneumatic jack comprises a tubular body (14) closed at one end and open at the other end. A hollow rod (9) is slidably mounted in the body (14) in a sealed manner and in the rod is formed a first chamber (18) containing a freely slidable piston (19) which divides the chamber into two compartments (18a, 18 b) which are sealed off from each other, a second chamber (23) being defined between a transverse end wall (21) constituting the end of the hollow rod (9) and the inner wall of the body (14). The transverse end wall (21) is provided with a nozzle (22) putting the second chamber (23) in communication with the neighbouring compartment (18b) of hollow rod (9). The compartment (18b) and the second chamber (23) are filled with a hydraulic liquid under pressure and the second compartment (18a) is filled with a pressurized gas. This jack automatically and instantaneously corrects the decreases in tension of the track (1) in the static state, subsequent to wear or expansion of the track and rollers.

Abstract: A shock absorber having a hollow slide slidably mounted in a fixed member disposed in a sleeve inside the body, separated from the latter by an annular gap and having an opening which communicates with a conduit opening into an a hydraulic chamber. The fixed member is mounted with clearance in the sleeve and is provided with radial ports communicating with the interior of the slide which is biased against the fixed member by an elastic return member bearing on the body. The slide is arranged in such manner as to be capable of occupying alternately a first position, in which it closes any communication between the annular gap and the interior of the slide when the suspension element is subjected to a low frequency oscillation less than .sqroot.