PISTON OPERATED FLUID DISPENSING DEVICE

摘要

In a fluid dispenser a spring biased piston is mounted for reciprocable movement along a stem member which is moved longitudinally to actuate the dispenser. A metering chamber is located between the end of the piston and the end wall of a cylindrical chamber in which the piston is mounted, and axial passageways extending from opposite ends of the stem connect the metering chamber to a discharge location when the stem is in a discharge positon and connect the metering chamber to a fluid reservoir when the stem is in a fill position.