Abstract: A system for applying sealant material to the welded seams of an automobile body including a reciprocating piston pump for supplying the material under pressure from a reservoir to an overhead distribution manifold. From the manifold the material is supplied to a plurality of extrusion guns through drop lines, each of which includes a pressure regulator and volumetric metering gear pump for maintaining a constant flow rate to the guns irrespective of pressure changes which may occur in the distribution manifold.

Abstract: A novel heat exchanger structure, for a hand-held adhesive gun of the type adapted to discharge a heated thermoplastic adhesive through a discharge valve located in the gun's barrel. In preferred form, the novel heat exchanger includes a heat exchanger core fixed in location within a heater body's bore. The heat exchanger core has spiral threads on the outer surface thereof, and the bore's surface has spiral threads thereon, too. The heat exchanger core's threads are sized relative to the inlet bore's threads such that the core can be threaded into the bore, and such that the threads cooperate to define a spiral path about the core through the bore from one end to the other, thereby defining a spiral heat exchange path through the gun's heater body. This novel heat exchanger is particularly adapted to elevate the temperature of the molten adhesive, just prior to dispensing it, above that temperature level at which the molten adhesive is supplied to the hand gun.

Abstract: A thermoplastic material dispensing apparatus adapted to translate feedstock from a solid state to a molten state by a novel heater block structure, and to discharge the molten feedstock through a novel discharge valve in response to operation of a novel trigger device. A novel annular cooling chamber is established about the dispenser's barrel to maintain a solid/melt interface inside the barrel adjacent to the heater block structure, that zone being air cooled by inlet air taken from a single inlet air line. The inlet air from the single line also drives the dispenser's ram through use of a novel pneumatic motor/spool valve mechanism. The spool valve is manually stroked forward to extend the dispenser's ram for extruding the feedstock, and is manually stroked rearward to retract the ram for recharging.

Abstract: A novel handle structure, and a novel heat exchanger structure, for a hand-held adhesive gun of the type adapted to discharge a heated thermoplastic adhesive through a discharge valve located in the gun's barrel. In preferred form, the novel handle structure is positioned at the aft end of the gun's barrel, and has a longitudinal axis extending rearwardly of the gun's barrel and located at an acute angle relative to the longitudinal axis of the gun's barrel. The gun's handle is positionable about the gun barrel's longitudinal axis between at least two operating locations, one being positioned 180.degree. from the other. A gun control switch is mounted interiorly of the handle, the switch being mechanically operated by the gun's trigger.

Abstract: A thermoplastic material dispensing apparatus adapted to translate feedstock from a solid state to a molten state by a novel heater block structure, and to discharge the molten feedstock through a novel discharge valve in response to operation of a novel trigger device. A novel annular cooling chamber is established about the dispenser's barrel to maintain a solid/melt interface inside the barrel adjacent to the heater block structure, that zone being air cooled by inlet air taken from a single inlet air line. The inlet air from the single line also drives the dispenser's ram through use of a novel pneumatic motor/spool valve mechanism. The spool valve is manually stroked forward to extend the dispenser's ram for extruding the feedstock, and is manually stroked rearward to retract the ram for recharging.

Abstract: A device including an applicator wheel for applying molten adhesive to a substrate as the substrate is moved over the surface of the wheel. The device includes a reservoir within which the wheel is partially submerged in molten adhesive and a doctor blade for controlling the thickness of adhesive applied to the substrate. The reservoir is so configurated that so long as the wheel is rotating, there is a continuous flow of molten adhesive from the pool beneath the wheel up to the doctor blade, along the underside of the doctor blade and back to the pool via channels in the end plates of a reservoir. To prevent the substrate from adhering to the surface of the wheel, stripper fingers extend parallel to the path of movement of the substrate and ride within annular channels or grooves in the periphery of the wheel.

Abstract: A device for sensing and controlling liquid level in a reservoir container. The device includes a sensing element in the form of a displacer which enters the liquid through the surface and displaces a predetermined volume. The displacer is located in a surge tank into which the liquid is initially fed and from which it is supplied to the reservoir. The displacer is mounted on an arm of a lever, the displacer being counterbalanced to respond to a liquid level in the surge tank. The lever carries a switch actuating mechanism which is moved in response to a change in the liquid level in the surge tank and which controls actuation of a single acting piston pump air motor to supply liquid to the surge tank.