Abstract: A housing for an exhaust fluid pump electronics and tank unit may include a chamber and a deflection flange. The housing may include a removable cover including a vent and a cover flange. The cover flange may be removably coupled to the deflection flange. A duct may be disposed on the housing and capable of fluidly communicating the chamber to a negative pressure source.

Abstract: A method and apparatus for dispensing multi-component foamable fluid plastic materials such as polyurethane foams. The apparatus includes a mixing chamber defined by an axial passage in a support body structure. The mixing chamber receives reactant fluids for mixing then allows the fluids to exit through an opening at one end of the axial passage. Two fluid inlet openings in a wall of the axial passage admit reactant fluid into the mixing chamber. Two mixing chamber fluid inlets formed in the support body structure communicate reactant fluid sources with the mixing chamber through the inlet openings. When retracted, a valve needle in the axial passage exposes the inlet openings to admit reactant fluids into the mixing chamber. When advanced, the needle closes off the inlet openings and pushes the mixed fluids from the mixing chamber. The valve needle includes three parallel helical grooves that help purge the mixing chamber of unreacted and reacted fluids.

Abstract: An apparatus for applying a foamable fluid plastic material including reactant fluids that form a foam when heated and mixed. A reactant fluid dispenser supplies the reactant fluids to a heated applicator gun mixing chamber at a constant flow rate despite any differences in viscosity. A valve needle extends into the mixing chamber and exposes fluid inlet openings when retracted, permitting the reactant fluids to flow into the mixing chamber. When advanced, the needle closes off the fluid inlet openings and dispenses the mixed fluids. A heater prevents the gun from drawing heat energy from initial quantities of the pre-heated reactant fluids which would prevent initial quantities of the fluids from reacting properly. The valve needle is disposed in a sleeve that defines the mixing chamber and is disposed in a sleeve receptacle of the gun.