Leveling valve for controlling the position of a first element with respect to a second element, and application of such a valve to a pneumatic cushion suspension.

摘要

1. Levelling valve (V) intended to control the holding of a first element (E1) in a predetermined position with respect to a second element (E2), it being possible for the two elements to be displaced with respect to one another and the two elements being linked by pressurized fluid-operated linking means (L), comprising on the one hand a valve body (1) intended to be fixed to one of the elements, this valve body being provided with an orifice (3) for the entry of pressurized fluid, an orifice (4) for joining to the fluid-operated linking means (L) and an outlet orifice (5) and on the other hand a distributor assembly (2) which is movable in the valve body (1), the displacements of the distributor assembly (2) with respect to the valve body (1) being controlled by the relative displacements of the two elements (E1, E2) such that the valve (V) ensures either admission of pressurized fluid into the fluid-operated linking means (L) or evacuation of the fluid towards the outlet in order to bring the two elements (E1, E2) which have been displaced into the desired relative position, the valve body (1) having an inner chamber (21) into which opens the orifice (4, 4a) for joining to the fluid-operated linking means (L), it being possible for this chamber (21) to be connected, by way of the distributor assembly (2), either to the orifice (3) for entry of pressurized fluid or to the outlet orifice (5), the said inner chamber (21) of the valve body (1) being closed at each end by a flap valve (22, 23), the distributor assembly (2) comprising means (24) for controlling the displacements of the flap valves (22, 23), each flap valve (22, 23) having a head (33, 38) of larger diameter than that of a tail (32, 39) which extends on the opposite side of the chamber (21), the heads (33, 38) being suitable for co-operation with a seal seat provided at each end of the chamber (21), characterized in that each flap valve (22, 23) is controlled independently of one another, in that each head (33, 38) is located inside the chamber (21), and in that the seal seats are fixed.