Hydraulic shock absorber

Claim 1

A HYDRAULIC SHOCK ABSORBER OPERABLE WITH TEMPERATURE VARIATIONS FOR CONTROLLING THE RELATIVE MOVEMENTS OF TWO MEMBERS, COMPRISING A SUBSTANTIALLY CYLINDRICAL CASING SECURED TO ONE OF SAID MEMBERS, SAID CASING ENCLOSING A WORKING CHAMBER CONTAINING A HYDRAULIC DAMPING FLUID, A PISTON ADAPTED TO RECIPROCATE IN SAID WORKING CHAMBER, A PISTON ROD FIXED TO SAID PISTON AND CONNECTED TO THE OTHER OF SAID RELATIVELY RECIPROCATING MEMBERS, THE PISTON COMPRISING TWO IDENTICAL AND ADJACENT PISTON PARTS FORMING A PISTON ASSEMBLY IN THE CASING AND EACH PISTON PART HAVING A VALVE DISC AND A VALVE CONTROL DISC DISPOSED IN A PLANE BY THE SIDE OF AND PARALLEL TO THE VALVE DISC, SAID DISCS HAVING DIFFERENT COEFFICIENTS OF THERMAL EXPANSION, AND SAID VALVE DISC BEING PROVIDED WITH SHAPED HOLES FORMING PASSAGES FOR THE HYDRAULIC FLUID WHOSE EFFECTIVE CROSS SECTIONAL AREAS ARE CONTROLLED BY THE VALVE CONTROL DISC WHICH COVERS AT THE SAME TIME ALL THE SHAPED HOLES IN THE VALVE DISC WITH DIFFERENT MAGNITUDES OF EXPANSION OF BOTH DISCS IN RADIAL DIRECTION UPON TEMPERATURE VARIATIONS, AND A SPRING IN EACH PISTON PART TO BEAR AGAINST THE VALVE CONTROL DISC SO THAT THE LATTER WILL ACT AS A NON-RETURN VALVE WHEN SUBJECTED TO THE PRESSURE OF THE LIQUID.