Hydraulic power control system
AssigneeCaterpillar Inc.
InventorMichael S. Lukich
Life of this patent
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Abstract
Large work vehicles include hydraulic implement control systems having an hydraulic pump being driven by an internal combustion engine. The subject invention provides a method and apparatus for controlling such an hydraulic system to limit engine lug. The invention includes a sensor for producing a parameter signal indicating the load on the engine and a pump control for varying the displacement of the variable displacement pump in response to engine load increasing above a predefined level. The response of the pump control is restricted to allow the engine to reach a predefined operating state.
Claims9
An apparatus for controlling a hydraulic system having an engine and a variable displacement pump, comprising:
- means for sensing a hydraulic system operating parameter and responsively producing a parameter signal being indicative of the load on the engine;
- a pump control for varying the displacement of the variable displacement pump in response to said parameter signal indicating a load on the engine increasing above a predefined level;
- delay means for restricting the response of said pump control to allow the engine to reach a predefined operating state;
- and
- wherein said engine includes a turbocharger and said delay means restricts the response of said pump control in response to turbocharger boost pressure.
An apparatus for controlling a hydraulic system having an engine and a variable displacement pump, comprising:
- means for sensing a hydraulic system operating parameter and responsively producing a parameter signal being indicative of the load on the engine;
- a pump control for varying the displacement of the variable displacement pump in response to said parameter signal indicating a load on the engine increasing above a predefined level;
- delay means for restricting the response of said pump control to allow the engine to reach a predefined operating state;
- wherein said predetermined operating state is a predetermined amount of lug;
- and
- an operator interface for allowing an operator to adjust said predetermined amount of lug.
An apparatus for controlling a hydraulic system having a variable displacement pump and an engine having a turbocharger, comprising:
- means for sensing a hydraulic system operating parameter and responsively producing a parameter signal being indicative of the load on the engine;
- means for sensing the boost pressure of the turbocharger and responsively producing a boost signal;
- a pump control for varying the displacement of the variable displacement pump in response to said parameter signal indicating a load on the engine increasing above a predefined level;
- and
- delay means for restricting the response of said pump control to allow said boost signal to reach a predefined level.
Dependencies are inferred from the claim text.