Controlling Electrohydraulic Systems with Unique Low-Cost Valves 2002-01-1459
Combine 25 years of electrohydraulic component, production, and system experience with control theory into a new valve design incorporating both nozzle-flapper and solenoid components, and you obtain an innovative, differential pressure control pilot valve (PCP). Utilizing a single component that integrates many functions, this invention reduces a complicated valve into a simple low-cost assembly, yielding a multi-purpose (patent-pending) electrohydraulic servovalve.
This PCP has been combined with several patented boost stages to yield pressure control servovalves (PCS) and flow control servovalves (FCS) that can be utilized in construction, industrial, and agricultural environments. The new, simplified and symmetric PCP/PCS can drive a pump directly with an option of built-in electronic rotational feedback. The PCP generates servovalve performance at less than proportional valve costs. These controls can be utilized in both open and closed-circuit arrangements.