Double acting pneumatic driven pump with regulating valve

摘要

A fluid flow machine wherein a reciprocating piston type pump for a flowable material which must be subjected to a pronounced pressurizing action is operated by a double-acting pneumatic motor which is disposed at a level above and is spaced apart from the pump. The unit which regulates the admission of compressed air into and the evacuation of spent air from the motor is installed between the motor and the pump at a level immediately above a chamber for a supply of liquid medium serving to lubricate and clean the piston rod which transmits motion from the piston of the motor to the pump piston. A common cylindrical envelope which is permeable to air surrounds the motor and the regulating unit and defines a large expansion chamber for spent air to thus reduce noise when the machine is in use. The regulating unit need not extend radially beyond the motor and/or pump housing, and this unit occupies space which is invariably provided between the chamber and the motor so that the placing of the regulating unit into such space does not contribute to the bulk of the machine.