Dual pressure fluid system and method of use
AssigneeCaterpillar Inc.
InventorDennis D. Feucht
Life of this patent
Estimating the term…
Abstract
A fluid system for supplying low and high pressure fluid is provided. A first pump discharges a first pump flow. A filter receives a first portion of the first pump flow and discharges a filter flow. A first accumulator receives a first portion of the filter flow. A valve receives a second portion of the first pump flow and a second portion of the filter flow, and discharges a valve flow. The valve is movable between a first position, providing a first flow path between the second portion of the first pump flow and the valve flow, and a second position, providing a second flow path between the second portion of the filter flow and the valve flow. A second pump receives the valve flow and discharges a second pump flow. A second accumulator receives the second pump flow.
Claims21
A fluid system for supplying a low pressure fluid and a high pressure fluid, the fluid system comprising:
- a first fluid pump configured to discharge a first fluid pump outlet flow, which is divisible into a first and a second portion;
- a fluid filter connected to said first fluid pump to receive said first portion of said first fluid pump outlet flow and configured to discharge a fluid filter outlet flow, which is divisible into a first and a second portion;
- a low pressure fluid accumulator connected to said fluid filter to receive said first portion of said fluid filter outlet flow;
- a priority valve connected to said first fluid pump to receive said second portion of said first fluid pump outlet flow, connected to said fluid filter to receive said second portion of said fluid filter outlet flow, and configured to discharge a priority valve outlet flow, said priority valve movable between a first position, which provides a first priority valve fluid flow path between said second portion of said first fluid pump outlet flow and said priority valve outlet flow, and a second position, which provides a second priority valve fluid flow path between said second portion of said fluid filter outlet flow and said priority valve outlet flow;
- a second fluid pump connected to said priority valve to receive said priority valve outlet flow and configured to discharge a second fluid pump outlet flow;
- and
- a high pressure fluid accumulator connected to said second fluid pump to receive said second fluid pump outlet flow.
A pressure and temperature controlled valve for controlling the flow path of a fluid, the valve comprising:
- a housing having a first fluid inlet port, a second fluid inlet port, and a fluid outlet port;
- a spool located within said housing, said spool movable between a first position, at which flow of the fluid along a first flow path between said first fluid inlet port and said fluid outlet port is passed and flow of the fluid along a second flow path between said second fluid inlet port and said fluid outlet port is blocked, and a second position, at which flow of the fluid along said first flow path is blocked and flow of the fluid along said second flow path is passed;
- a resilient element biasing said spool relative to said housing to a first position;
- and
- a thermally reactive element exposed to a temperature input, said thermally reactive element having a first configuration in response to said temperature input being at a first temperature, said first configuration allowing said spool to be in said first position, and having a second configuration in response to said temperature input being at a second temperature, said second configuration preventing said spool from being in said first position.
A method for supplying a low pressure fluid and a high pressure fluid, the method comprising:
- pumping a fluid through a first fluid pump to create a first pumped flow;
- filtering a first portion of said first pumped flow to create a filtered flow;
- passing a first portion of said filtered flow to a first inlet port of a priority valve;
- passing a second portion of said first pumped flow to a second inlet port of a priority valve;
- transmitting one of said first portion of said filtered flow and said second portion of said first pumped flow through said priority valve to create a priority valve outlet flow;
- passing said priority valve outlet flow to a second fluid pump;
- and
- pumping said priority valve outlet flow through said second fluid pump to create a second pump outlet flow.
Dependencies are inferred from the claim text.