Modular hydraulic hybrid drivetrain
AssigneeThe United States of America, as represented by the Administrator of the U.S. Environment Protection Agency
InventorCharles L. Gray, Jr.
Life of this patent
Estimating the term…
Abstract
A drive module for a hydraulic hybrid vehicle includes two variable displacement over-center bent-axis hydraulic pump/motors with respective yokes that reside and pivot within a common fluid-filled case. The cylinder barrel of each pump/motor is connected to high pressure through fluid-conducting yoke legs, and is connected to low pressure through the fluid-filled case, which is connected by a port to a low pressure source. As a drivetrain for a vehicle, one pump/motor acts primarily as a pump driven by an engine and the other pump/motor acts primarily as a motor to propel the vehicle. A removable support structure facilitates installation to a variety of vehicle chassis.
Claims24
An integrated drive module for a motor vehicle, comprising a hydraulic drive unit, wherein the hydraulic drive unit comprises:
- a case filled with working fluid;
- a low pressure supply port placing the case in fluid communication with a low pressure fluid source;
- a high pressure supply port placing the hydraulic drive unit in fluid communication with a high pressure fluid source;
- first and second bent-axis pump/motors, having respective first and second yokes pivoting within said case, said yokes each carrying a respective cylinder barrel, and each yoke providing low pressure fluid supply to its respective cylinder barrel by means of a respective low pressure port;
- said low pressure port being in fluid communication with the fluid-filled interior of said case, respective low pressure ports being thereby in fluid communication with each other;
- an input shaft for connection of the first pump/motor to a mechanical power source;
- and
- an output shaft for connection of the second pump/motor to a mechanical power output.
An integrated drive module for a motor vehicle, comprising a hydraulic drive unit, wherein the hydraulic drive unit comprises:
- a low pressure supply passage placing the integrated drive module in fluid communication with a low pressure fluid source;
- a high pressure supply passage placing the integrated drive module in fluid communication with a high pressure fluid source;
- first and second bent-axis pump/motors having respective first and second yokes pivoting within a common case, said yokes each carrying a respective rotating group, and each yoke providing low pressure fluid supply to its respective rotating group by means of a low-pressure manifold connecting the low pressure supply to the low pressure yokes of first and second pump/motors;
- a high-pressure manifold connecting the high pressure supply of the first pump/motor with said high pressure fluid source, and connecting the high pressure supply of the second pump/motor with said high pressure fluid source;
- an input shaft for connection of the first pump/motor to a mechanical power source;
- and
- an output shaft for connection of the second pump/motor to a mechanical output.
A method of installing a hydraulic hybrid drivetrain on a motor vehicle, comprising:
- placing the components of an integrated hydraulic hybrid drive module on a common removable support structure, wherein the components of the integrated hydraulic hybrid drive module comprise a high pressure accumulator, a low pressure reservoir, a hydraulic drive unit, and associated hoses, and the hydraulic drive unit comprises an engine pump and hydraulic drive motor positioned in a common case;
- positioning the integrated hydraulic hybrid drive module and removable support structure underneath the motor vehicle;
- raising the integrated hydraulic hybrid drive module and removable support structure;
- attaching the integrated hydraulic hybrid drive module or removable support structure to frame rails of the motor vehicle;
- connecting an input shaft of the engine pump to a mechanical power source of the motor vehicle;
- connecting an output shaft of the hydraulic drive motor to a mechanical power output of the motor vehicle;
- and
- removing the removable support structure.
Dependencies are inferred from the claim text.