Abstract: An adjustment means for variable height adjustment of hydraulically or pneumatically operable supports, e.g. legs on tables, chairs, beds etc., adjustment means for simultaneously raising and lowering all supports and for separately adjusting each of said supports to suit the contour of the floor surface or similar foundation comprised of pressure chambers (13) in the housing (11) of the adjustment means (10), the number corresponding to the number of supports, each pressure chamber having a piston (14), which by way of an adjusting screw (15) cooperates with a driving nut (16), which is unrotatably but axially displaceably arranged in the housing. The driving nut is displaced by means of a threaded spindle (17) which is rotatably but undisplaceably mounted in the housing.

Abstract: An air cylinder including a piston adapted to be stopped freely in any position as desired includes an automatic restoring type air cylinder member and a hydraulic cylinder member. The piston is formed with a hydraulic cylinder chamber having fitted therein a hydraulic fixed piston of the hydraulic cylinder member so that the piston can move freely in a cylinder body. An oil chamber defined by the end of the hydraulic fixed piston and the end of the hydraulic cylinder chamber is communicated with an oil tank via an oil passage mounting a check valve that can be opened by pressing means including a pilot piston and other parts.

Abstract: In a brake actuator device having a fluid pressure actuated service brake and a spring-applied, fluid pressure released auxiliary brake that cooperates with the service brake via a friction clutch mechanism, there is provided a manual release mechanism for releasing the spring-applied brake in the absence of fluid pressure. The manual release mechanism operates to relieve the tension of the actuating spring by causing the piston through which the spring operates to engage a stop formed on the casing of the brake actuator device, so that the spring is caged at its opposite ends by the casing of the brake actuator device. Extension of a retracting screw to initiate the manual release operation is automatically retracted following engagement of the spring piston with its stop to reset the manual release mechanism in readiness for a subsequent operation.

Abstract: To provide for separate expansion control actions at the top and bottom edges of the skirt of an expansion-controlled light alloy piston, to prevent a direct propagation of deformation between the top and bottom edges of the skirt and to reduce the skirt area between the top and bottom edges of the skirt, the skirt of the piston is provided at its periphery with a transverse slot, which extends around the entire periphery of the skirt or part thereof and is disposed on the level of the piston pin boss.

Abstract: Servo unit provided with an internal bracing member which is stressed upon assembly, permitting mounting thereof to a vehicle by means of only two fixing screws. The bracing member has an initial shape which is curved in a given direction, forming a clearance between the inside face of the mounting wall and two regions of the bracing member against which the screws bear. The clearance is eliminated when the bracing member is pressed against the inside face at the moment of definitive fixing of the screws with respect to the casing. The bracing member of the invention provides for better distribution over the whole of the inside face of the braking reaction forces which are applied to the casing.