Abstract: Diaphragms for pumps, compressors and the like are provided with a substantially flat planar end face confronting the media being pumped or compressed and have an outer peripheral zone for clamping the circumference of the diaphragm in the pump or compressor housing, an annular intermediate flexing or bending zone adjacent the clamping area, and a central thickened work zone with the flexible bending zone increasing in thickness toward the central working zone. The bending or flexing of the annular intermediate zone is limited to one side of the flat planar end face and the bending stresses are minimized.

Abstract: A method and device for regulating diaphragm pumps during standby which reduces power input demands during non-delivery standby conditions while assuring a maintenance of working pressure upon a sudden change to a delivery condition which utilizes pressure of the drive fluid as a regulating variable by retaining a portion thereof outside of the drive chamber and using the pressure of the retained portion to control one or both of an intake aperture to the drive chamber or a pressure limiting outlet valve from the drive chamber.