FLUID ACTIVATED SWITCH APPARATUS

A pneumatic switch unit includes a switch housing. A conductive contact spring is mounted between diametric supports, one being adjustable. The spring has a central actuator arm and an offset contact arm interconnected to an encircling frame. A two piece switch actuator has clamp members clamped to the actuator arm. Separate end closure members secured to the switch housing, ends. The closure member may clamp a diaphram against the housing, with the diaphram engaging the actuator. The closure member may have a mechanical actuating member or a simple closure plate engaging the actuator. The two switch housings may be mounted to the opposite sides of a single pressure chamber with end diaphrams closing the opposed ends of the switch housing. The pressure actuates both switch units to establish a sequence switch unit. The spring has a rectangular frame with a central opening having an actuating arm therein. the opposite spring ends are mounted in supports one of which is adjustable. A contact arm is secured to one end and projects parallel to the side. The opposite spring corner includes a notch to control the snap action. An alternate spring has an annular ring with a chordal actuator arm and a chordal contact arm. The spring is mounted on a line perpendicular to the two arms.