Charging an accumulator by a heat engine
AssigneeRegie Nationale des Usines Renault
InventorPatrice Baudoin
Life of this patent
Estimating the term…
Abstract
A. Charging an oleopneumatic accumulator with energy. B. Automatic charging of the oleopneumatic accumulator (1) by the intermediary of the heat engine (101) driving the hydraulic pump with variable displacement (104), whose displacement is altered with the aid of a jack (122) supplied by a three-position valve (120), provided with two control coils (120a and 120b). A logic block (70) is connected to a sensor (5) of the accumulator pressure, to a speed sensor (11) of the rotation of the engine, and to a sensor (25) of the displacement of the pump (104) and produces control signals for the two coils (120a and 120b) and for a discharge electrovalve (121). C. Used for hybrid vehicles or for storing energy in oleopneumatic form.
Claims9
A method of regulating the pressure in an accumulator to obtain a pressure therein which lies between two predetermined values using a variable-displacement pump driven by an internal combustion engine to charge the accumulator, the method comprising the following steps:
- sensing and generating a signal representative of the pressure within the accumulator;
- placing the engine in an operable condition when the sensed pressure drops to a value below the lower of the two predetermined values and adjusting the pump to have a negative displacement so that it operates as a motor driven by fluid under pressure from the accumulator thereby driving the engine until the engine reaches a speed at which it is self-sustaining;
- increasing the displacement of the pump until it reaches a positive value after the engine has reached the self-sustaining speed thereby loading the engine;
- controlling the displacement of the pump to maintain the speed of the engine at or about a predetermined value;
- and
- placing the engine in an inoperable condition and adjusting the pump to have zero displacement when the sensed pressure in the accumulator exceeds the higher of the two predetermined values.
An arrangement comprising a fluid pressure accumulator, a variable displacement pump, an internal combustion engine connected for driving the variable-displacement pump to charge the accumulator, and control means, the control means including sensors for sensing the pressure in the accumulator, the speed of the engine and the displacement of the pump and being adapted to:
- a. put the engine into an operable condition and adjust the pump to have a negative displacement when the pressure in the accumulator drops to a value below the lower of two predetermined values;
- b. increase the displacement of the pump, when the engine reaches a self-sustaining speed, to a positive value and to control the displacement of the pump to maintain the speed of the engine at or about a predetermined value;
- and
- c. put the engine into an inoperable condition and adjust the pump to have a zero displacement when the pressure within the accumular rises to a value above the higher of the two predetermined values.
Dependencies are inferred from the claim text.