Leydig, Voit & Mayer, Ltd.
Directional control valve and valve assembly in an asphalt distributor
A directional control valve having three positions controls the direction of flow through an asphalt distributor. The directional control valve is interposed between a pump and a feed line assembly to a spray bar. The directional control valve has a first position in which flow is recirculated through the pump, a second position in which flow is delivered to the spray bar and a third position providing for handspray and transfer operations. A pressure relief valve is provided for controlling return flow of asphalt from the spray bar to the tank. The pressure relief valve is open in spray bar circulation mode and is closed during a spraying mode. According to the preferred embodiment the directional valve and pressure relief valve are contained within a modular control valve assembly. The directional control valve eliminates the need to reverse the flow in one of the individual feed lines and feed line assembly connecting the modular control valve assembly to the spray bar. The feed line assembly includes a delivery and return line running coaxial or otherwise adjacent for heat transfer therebetween. The directional control valve reduces the quantity and lengths of exposed valving and plumbing associated with prior asphalt distributors.
E. D. Etnyre & Co.
E Y E
E01C Y10T E01C
inventional additional inventional
Patrick Thomas R. Jeremey
O'Brien Brown Heller