Abstract: A linear variable differential transformer includes a primary winding and two secondary windings in spaced stacked relation on a core unit. The core unit includes similar cup-shaped pot cores mounted in opposed opening relationship and having abutting cylindrical outer walls and spaced cylindrical inner walls define an annular chamber within which the windings are located. A core axis located within the central air gap between the inner walls and terminates in close relation to the windings. A movable stem couples the core to a pressure diaphragm transducer to locate the core in accordance with pressure.

Abstract: A diaphragm compressor includes a cylindrical piston and an annular diaphragm member with a central hub secured by a grommet within an annular recess in the piston face. The outer peripheral edge of the diaphragm is affixed between a clamp ring and a valve plate which has a central recess to form a compression chamber. The diaphragm has a convolution which opens toward the compression chamber. The valve plate has a projection complementing and mating with the convolution. A plurality of circumferentially spaced and radial intake ports lead to an annular piston intake opening inwardly of the diaphragm. A flexible, tee-shaped valve member includes a stem locked within the piston with a planar sealing disc having an outer bead abutting the inner piston face and overlying the intake opening. The stem may pass through a central opening with an outer stem enlargement creating a resilient clamping of the valve member to a holding portion of the piston.