초록 ▼

An improved energy-conserving servoactuator has at least one valve operatively associated with a double-acting fluid-powered actuator. When a load is applied to the actuator, the pressure in one actuator chamber will be greater than in the other. If the load is “opposing”with respect to the desired

An improved energy-conserving servoactuator has at least one valve operatively associated with a double-acting fluid-powered actuator. When a load is applied to the actuator, the pressure in one actuator chamber will be greater than in the other. If the load is “opposing”with respect to the desired direction of actuator movement, fluid is supplied to the higher pressure chamber and is permitted to flow from the lower pressure chamber. However, if the load is “aiding”with respect to the desired direction of actuator movement, fluid in the higher pressure chamber is permitted to flow into the lower pressure chamber without drawing fresh fluid from the source.

대표청구항 ▼

In a servomechanism associated with a source of pressurized fluid at a supply pressure, the improvement which comprises: a first valve and a second valve, each of said valves having one member movable relative to another member, each of said other members having a supply opening communicating with s

In a servomechanism associated with a source of pressurized fluid at a supply pressure, the improvement which comprises: a first valve and a second valve, each of said valves having one member movable relative to another member, each of said other members having a supply opening communicating with said source, having a return opening, and having a control opening, each of said one members being movable within a first positional range relative to the associated other member to increase the pressure at the associated control opening and being movable within a second positional range to decrease the pressure at the associated control opening; a first conduit communicating one of said first valve supply and return openings with the like one of said second valve supply and return openings; a first driver operatively arranged to move said first valve one member to a desired position relative to said first valve other member; a second driver operatively arranged to move said second valve one member to a desired position relative to said second valve other member; a sensor for determining a pressure differential at said first and second valve control openings; and a controller operatively associated with said sensor and with said drivers for causing said first valve one member to move to an appropriate position within one of its positional ranges and for causing said second valve one member to move to an appropriate position within the other of its positional ranges when the pressure at one of said control openings is greater than the pressure at the other of said control openings, and for causing both of said first and second valve one members to move to appropriate positions within like ones of said positional ranges when the pressure at said one control opening is less than the pressure at said other control opening.