# US 2014/0150738 A1 · Cooling system having shock reducing valve > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150738 A1 - Document ID: US20140150738A1 - Status: Published application - Kind: A1 - Application number: 13/691,127 - Filed: 2012-11-30 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Caterpillar Inc. - Applicants: Caterpillar Inc. - Inventors: Neil Alan Terry; James Carl Durand; Joseph Lee Kennedy - Web page: https://patentgrep.com/patent/US20140150738A1 ## CPC - F01P 11/20: concerning atmospheric freezing conditions, e.g. automatically draining or heating during frosty weather - F01P 7/16: by thermostatic control - F01P 7/165: {characterised by systems with two or more loops} - F01P 2007/146: {using valves} - F01P 2011/205: {using heat-accumulators} - F01P 2060/08: Cabin heater - F02N 19/10: by heating of engine coolants - F01P: COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES (arrangements in connection with cooling of propulsion units in vehicles B60K11/00; heat-transfer, heat-exchange or heat-storage materials C09K5/00; {cooling of gas-turbine engines F02C7/12}; heat exchange in general, radiators F28) - F02N: STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR ## Abstract A cooling system for an engine includes a pump driven by the engine and configured to circulate coolant through the engine. The cooling system also includes a heat exchanger configured to receive coolant from the engine and to reduce a temperature of the coolant. The cooling system further includes a thermostat fluidly connected to the engine and the heat exchanger. The thermostat is configured to selectively direct coolant from the engine to the heat exchanger when a temperature of the coolant is greater than a temperature threshold of the thermostat. The thermostat is also configured to substantially block coolant from passing to the heat exchanger when the temperature of the coolant is less than or equal to the temperature threshold. The cooling system also includes a valve fluidly connected to the engine and the heat exchanger, and connected in parallel with the thermostat. The valve is configured to direct a portion of the coolant exiting the engine to the heat exchanger during a first operating condition. During the first operating condition, a pressure of the coolant exiting the engine is greater than a pressure threshold of the valve. ## Claims ### Claim 1 A cooling system for an engine, comprising: a pump driven by the engine and configured to circulate coolant through the engine; a heat exchanger configured to receive coolant from the engine and to reduce a temperature of the coolant; a thermostat fluidly connected to the engine and the heat exchanger, the thermostat configured to selectively direct coolant from the engine to the heat exchanger when a temperature of the coolant is greater than a temperature threshold of the thermostat, and to substantially block coolant from passing to the heat exchanger when the temperature of the coolant is less than or equal to the temperature threshold; and a valve fluidly connected to the engine and the heat exchanger, and connected in parallel with the thermostat, the valve configured to allow a portion of the coolant exiting the engine to pass through the valve to the heat exchanger during a first operating condition, wherein during the first operating condition, a pressure of the coolant exiting the engine is greater than a pressure threshold of the valve. ### Claim 2 (depends on 1) The cooling system of claim 1, wherein the thermostat and the valve are fluidly connected to the pump via a bypass line, and wherein during the first operating condition, a remainder of the coolant is directed to the pump by the thermostat via the bypass line in response to the temperature of the coolant exiting the engine being less than or equal to the temperature threshold. ### Claim 3 (depends on 2) The cooling system of claim 2, further including a second operating condition in which the temperature of the coolant exiting the engine is greater than the temperature threshold and the pressure of the coolant exiting the engine is greater than the pressure threshold of the valve, wherein during the second operating condition, the valve allows the portion of the coolant exiting the engine to pass through the valve to the heat exchanger in response to the pressure of the coolant exiting the engine being greater than the pressure threshold. ### Claim 4 (depends on 3) The cooling system of claim 3, wherein during the second operating condition, the thermostat directs the remainder of the coolant to the heat exchanger in response to one of expansion and contraction of a temperature-sensitive component of the thermostat. ### Claim 5 (depends on 3) The cooling system of claim 3, wherein during the second operating condition, the thermostat directs the remainder of the coolant exiting the engine to the heat exchanger, while substantially blocking passage of coolant from the engine to the pump via the bypass line, in response to the temperature of the coolant exiting the engine being greater than the temperature threshold. ### Claim 6 (depends on 2) The cooling system of claim 2, further including a second operating condition in which the pressure of the coolant exiting the engine is less than or equal to the pressure threshold, wherein during the second operating condition, the valve substantially blocks passage of the portion of the coolant from the engine to the heat exchanger in response to the pressure of the coolant exiting the engine being less than or equal to the pressure threshold. ### Claim 7 (depends on 6) The cooling system of claim 6, wherein during the second operating condition, the temperature of the coolant exiting the engine is less than or equal to the temperature threshold, wherein during the second operating condition, the thermostat directs the remainder of the coolant to the pump via the bypass line in response to the temperature of the coolant exiting the engine being less than or equal to the temperature threshold. ### Claim 8 (depends on 1) The cooling system of claim 1, wherein the portion of the coolant comprises between approximately 1% and approximately 5% of the coolant exiting the engine. ### Claim 9 (depends on 1) The cooling system of claim 1, further including a shunt system having a shunt tank fluidly connected to the heat exchanger, a shunt valve fluidly connected to the shunt tank, the shunt valve configured to vent air out of the shunt tank when a pressure in the shunt tank exceeds a shunt valve pressure threshold, and a shunt line fluidly connected to the shunt tank and the pump. ### Claim 10 A cooling system for an engine, comprising: a pump driven by the engine and configured to circulate coolant through the engine; a heat exchanger configured to receive coolant from the engine and to reduce a temperature of the coolant; a thermostat fluidly connected to the engine, the pump, and the heat exchanger, the thermostat configured to simultaneously direct coolant from the engine to the heat exchanger while substantially blocking passage of coolant from the engine to the pump when a temperature of the coolant is greater than a temperature threshold of the thermostat; and a valve fluidly connected to the engine and the heat exchanger, and connected in parallel with the thermostat, the valve configured to allow a portion of the coolant exiting the engine to pass through the valve to the heat exchanger when a pressure of the coolant is greater than a pressure threshold of the valve, and to substantially block passage of coolant to the heat exchanger when the pressure of the coolant is less than or equal to the pressure threshold. ### Claim 11 (depends on 10) The cooling system of claim 10, further including a shunt tank fluidly connected to the heat exchanger, the valve, and the thermostat, the shunt tank being configured to receive coolant from the heat exchanger. ### Claim 12 (depends on 11) The cooling system of claim 11, wherein the valve comprises an air passage configured to direct air collected from coolant exiting the engine to the shunt tank. ### Claim 13 (depends on 11) The cooling system of claim 11, wherein the shunt tank includes a shunt valve configured to release air stored in the shunt tank in response to a pressure within the shunt tank being greater than a pressure threshold of the shunt valve. ### Claim 14 (depends on 11) The cooling system of claim 11, wherein the heat exchanger is configured to direct coolant to a first inlet of the pump, the thermostat is configured to direct coolant to a second inlet of the pump, and the shunt tank is configured to direct coolant to a third inlet of the pump. ### Claim 15 (depends on 10) The cooling system of claim 10, wherein the temperature threshold is between approximately 80 degrees Celsius and approximately 90 degrees Celsius, and wherein the pressure threshold is between approximately 5 psi and approximately 20 psi. ### Claim 16 (depends on 10) The cooling system of claim 10, wherein the valve and the thermostat are disposed within a common housing, the housing being selectively fluidly connected to the pump, the engine, and the heat exchanger. ### Claim 17 A method of cooling an engine, comprising: receiving heated coolant from the engine; allowing a portion of the coolant from the engine to pass through a valve to a heat exchanger during a first operating condition, in response to a pressure of the coolant being greater than a threshold pressure; and directing, by a thermostat connected in parallel with the valve, a remainder of the coolant to a pump during the first operating condition, in response to a temperature of the coolant being less than or equal to a threshold temperature. ### Claim 18 (depends on 17) The method of claim 17, further including directing the portion of the coolant to the heat exchanger, during a second operating condition different than the first operating condition, in response to the pressure of the coolant being greater than the threshold pressure, and directing the remainder of the coolant to the heat exchanger, during the second operating condition, in response to the temperature of the coolant being greater than the threshold temperature. ### Claim 19 (depends on 18) The method of claim 18, further including substantially blocking, with a thermostat, coolant from passing to the pump while simultaneously directing the remainder of the coolant to the heat exchanger with the thermostat. ### Claim 20 (depends on 17) The method of claim 17, further including substantially blocking the portion of the coolant from passing to the heat exchanger, during a second operating condition different than the first operating condition, in response to the pressure of the coolant being less than or equal to the pressure threshold, and directing the received coolant to the pump, during the second operating condition, in response to the temperature of the coolant being less than or equal to the temperature threshold.