Abstract: A hydraulic system for a vehicle mounted snowplow blade capable of lifting, lowering, and angling the blade right or left has a single 4-way valve controlling power flow to the lift and angling cylinders. Power flow to and return flow from the angle cylinders is controlled through the 4-way valve. Power flow to the lift cylinder is controlled through the 4-way valve and return flow from the lift cylinder to the reservoir is controlled through a separate two-way valve. Both valves are electrically operated by means of solenoids connected directly to the valve body.

Abstract: A control lever extends through a cruciform opening in a control box and inside of the box fixed electrical contacts surround its inner end in an array corresponding to the shape of the cruciform opening. A common electrical contact is connected to the lever. Selective movement of the lever into the guideways provided by the cruciform opening selectively completes electrical contact of the common contact with the fixed electrical contacts to energize a desired electrical circuit. The lever is spring biased so that, when the operating force is removed, the lever returns to a neutral position out of engagement with all fixed contacts. A solenoid is selectively engageable with the lever to restrict movement thereof from the neutral position.

Abstract: The operation of a 4-way, open-center, three position hydraulic valve is coordinated with the operation of the pump for the hydraulic system in which the valve is controlling flow. As the valve is moving from its open-center position to either one of its other two operative positions, a switch maintains the power circuit for the pump open and closes that circuit to activate the pump after the valve has assumed one of the other two positions.