Abstract: The ON behavior of a pressure switch or a valve (134) differs from its reset behavior by virtue of the fact that the movable pressurized part (126) is connected to one of the parts of a magnet assembly (112, 114) which are movable in relation to one another.

Abstract: In a servo-valve, a metal bellows (70) is fitted onto an end section (66) of valve stem (26,42) lying at a distance from the seal (22), one end of said metal bellows (70) being supported rigidly in housing (72), while its other end engages the end of the stem. The metal bellows (70) are located in a pressure chamber (62) which is connected by a condensate coil (74) to the valve intake (12), whereby the cross-sectional area of the metal bellows (70) is made to match the area of the passageway of the valve seat (16). In this way, it is possible to achieve an overall compensation of the forces at the seal (22) or a desired additional load in the closed or open direction.

Abstract: An adjustable lock for rotating drives, more particularly pipework fittings such as screwdown valves, gate valves or the like wherein the drive is required to make a number of revolutions. In the adjustable lock, a planetary transmission is provided as a reducing transmission in order to reduce drive rotation to at most one revolution and, therefore, to define a definite locking position.

Abstract: A valve of the type which is actuated under the pressure of the medium it controls and in which axially-aligned actuating and damping pistons are disposed within cylindrical relief and damping chambers and are connected to a valve element engageable with a valve seat disposed between inlet and outlet valve ports. The actuating piston acts under the pressure of the medium it controls to actuate the valve element in response to a reduction in pressure in the relief chamber. The invention itself resides in the provision of a restricted passageway which interconnects the relief and damping chambers whereby the pressure in the damping chamber will be reduced slowly in response to a reduction in pressure in the relief chamber whereby, if the valve should stick or otherwise become slow-acting, the pressure within the damping chamber will assist and insure that the valve is actuated even though it may not be in the best operating condition.

Abstract: A valve of the type which is actuated under the pressure of the medium it controls and in which axially-aligned actuating and damping pistons are disposed within cylindrical relief and damping chambers and are connected to a valve element engageable with a valve seat disposed between inlet and outlet valve ports. The actuating piston acts under the pressure of the medium it controls to actuate the valve element in response to a reduction in pressure in the relief chamber. The invention itself resides in the provision of a restricted passageway which interconnects the relief and damping chambers whereby the pressure in the damping chamber will be reduced slowly in response to a reduction in pressure in the relief chamber whereby, if the valve should stick or otherwise become slow-acting, the pressure within the damping chamber will assist and insure that the valve is actuated even though it may not be in the best operating condition.

Abstract: The stuffing box chamber in a fitting, particularly a valve, contains a deformable stuffing box seal. The seal includes conventional sealing material and a constituent material such as zinc or aluminum having a standard potential that is less positive in the electrochemical potential series than the potential of the material defining the stuffing box chamber, i.e., the constituent material is less precious. Dust, granules or filaments of less precious material are mixed with the standard sealing material. Another embodiment includes alternating layers of discs made from the conventional and less precious materials. A further embodiment provides that the less precious material is an envelope or coating surrounding the conventional sealing material.