Abstract: Apparatus for repeatedly dispensing measured portions of viscous substances is disclosed. The invention includes a body defining a bore within which is a sleeve defined floating measuring chamber. In the chamber is a sliding piston. Material to be dispensed is forced into the floating measuring chamber under pressure. A three-way, two-position air valve actuates the dispensing apparatus. Shifting of the air valve applies air pressure to one end of the floating measuring chamber, causing it to shift. This closes a material supply port and opens a material discharge port. The floating measuring chamber meters the flow of air to the floating piston so that the discharge velocity of the material being dispensed is controlled. At the end of the dispensing cycle, air under pressure is directed out through the material discharge port clearing it of residual material.

Abstract: A dispensing apparatus for dispensing viscous substances includes a cylinder encompassing a sliding sleeve which in turn receives a free sliding dispensing piston. Material to be dispensed is supplied to the sleeve under pressure. Air pressure is applied to the piston through the use of a three-way, two-position air valve, causing the sleeve to shift, thereby closing a supply port and opening a dispensing port in the apparatus and causing the dispensing piston to discharge material through the dispensing port.

Abstract: A dispensing apparatus for viscous substances includes a unitary plastic block housing provided with a vertical bore forming a dispensing cylinder and a horizontal three way spool valve operable for controlling a dispensing piston located in the aforementioned dispensing cylinder. The dispensing piston is attached to a shaft extending centrally upwardly of the dispensing cylinder and is adjustable for controlling the stroke of the dispensing piston and thereby the quantity of material dispensed. A common source of air pressure is applied to the minor area on the shaft side of the dispensing piston as well as to the material to be dispensed. The material under pressure is normally applied to the major side of the dispensing piston via the spool valve. When the spool valve is operated the supply of material is cut off and the dispensing cylinder is connected to an exit port, whereby the air pressure behind the dispensing piston is sufficient to force a predetermined quantity of material through the exit port.