DUAL COOLING SYSTEM FOR ENGINES

• US 3,752,132 A
• Filed: 04/19/1971
• Issued: 08/14/1973
• Est. Priority Date: 04/19/1971
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Erwin J.H. Bentz, Roger D. Hiserote
• Inventors: Bentz, Erwin J. H., Hiserote, Roger D.
• Primary Examiner(s): Goodridge, Laurence M.
• Assistant Examiner(s): Cox, Ronald B.
• Application Number:
  US05/135,497
• Time in Patent Office: 848 Days
• Field of Search: 123/119D,41.53,41.1 188/264
• US Class Current: 123/563
• CPC Class Codes: F01P 11/02 Liquid-coolant filling, overflow, venting, or draining devices automatic draining during freezing conditions F01P11/20
• CPC Class Codes: F01P 2003/187 arranged in series
• CPC Class Codes: F01P 2060/02 Intercooler
• CPC Class Codes: F01P 2060/06 Retarder
• CPC Class Codes: F01P 7/165 characterised by systems with two or more loops
• CPC Class Codes: F02B 29/0406 Layout of the intake air cooling or coolant circuit
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A dual cooling system comprises first and second closed circuits, each circuit including an air-to-liquid radiator therein. The first circuit is adapted to cool an internal combustion engine whereas the second circuit functions to cool air discharged from a turbocharger to the intake manifold of an internal combustion engine. The system may comprise means for bypassing the radiators when temperature levels fall below predetermined levels and a single supply and expansion tank for supplying the two circuits with cooling fluid. A baffle is positioned in the tank'"'"''"'"'s chamber to divide it into two compartments with each compartment communicating with one of the circuits.

Claims

1. A dual cooling system in combination with an internal combustion engine having a turbocharger operatively associated therewith and a heat exchanger operatively associated with said turbocharger, said system comprising a first closed circuit means for circulating a first cooling liquid therethrough including in series a first air-to-liquid radiator, first pump means having an inlet communicating with said first radiator and an outlet communicating with an inlet to said engine for circulating said first cooling liquid therethrough and to an outlet thereof and first thermostatically controlled bypass means for normally circulating said first cooling liquid through said first radiator when the temperature of said first cooling liquid exceeds a predetermined level but for bypassing said first radiator and for communicating said first cooling liquid directly to the inlet to said first pump means when the temperature of said first cooling liquid falls below said predetermined level and a second closed circuit means for circulating a second cooling liquid, completely and constantly independent of first cooling liquid flow through said first closed circuit means, therethrough including in series a second air-to-liquid radiator, second pump means having an inlet communicating with said second radiator and an outlet communicating with an inlet to said heat exchanger for circulating said second cooling liquid therethrough and to an outlet thereof and a hydrodynamic retarder, including a bladed rotor mounted on a rotatable shaft and a stationary housing enclosing said rotor to form a chamber adapted to be filled with a working fluid, having a retarder heat exchanger operatively connected thereto for cooling and circulating a working fluid to said retarder, said retarder heat exchanger located in said second closed circuit means for circulating said working fluid in heat exchange relationship with said second cooling liquid, a single supply and expansion tank operatively connected to said first and second closed circuit means, said tank having a vertically disposed baffle means therein dividing a chamber of said tank into first and second substantially isolated compartments communicating with said first and second closed circuit means, respectively, and first and second horizontally disposed baffle plates in said first and second compartments, respectively, dividing each compartment into a pair of subcompartments and vent means extending through each of said baffle plates to communicate each pair of sub-compartments with each other.

2. The invention of claim 1 further comprising second thermostatically controlled bypass means for noRmally circulating said second cooling liquid through said second radiator when the temperature of said second cooling liquid exceeds a predetermined level but for bypassing said second radiator and for communicating said second cooling liquid directly to the inlet to said second pump means when the temperature of said second cooling liquid falls below said predetermined level.

3. The invention of claim 1 further comprising another heat exchanger operatively connected in said first closed circuit means and to said engine for circulating engine oil in heat exchange relationship with said first cooling liquid.

4. The invention of claim 2 wherein said first bypass means is operatively connected between the outlet of said engine and said first radiator and wherein said second bypass means is operatively connected between the outlet of said heat exchanger and said second radiator.

5. The invention of claim 2 wherein said first bypass means is operatively connected between the outlet from said first radiator and said first pump means and wherein said second bypass means is operatively connected between an outlet from said second radiator and said second pump means.

6. The invention of claim 1 wherein said retarder heat exchanger is operatively connected between the outlet from said second pump means and the inlet to said turbocharger heat exchanger.

7. The invention of claim 1 wherein said retarder heat exchanger is operatively connected between the outlet from said turbocharger heat exchanger and said second radiator.

8. In a dual cooling system for an internal combustion engine, having a turbocharger operatively connected thereto, comprising a first closed circuit means, including a first air-to-liquid radiator, for circulating a first liquid therein to cool an internal combustion engine and a second closed circuit means, including a second air-to-liquid radiator, for cooling an auxiliary device, for circulating a second liquid therein, the invention comprising a single supply and expansion tank having baffle means therein dividing a chamber of said tank into first and second substantially isolated compartments communicating with said first and second closed circuit means, respectively, for at least substantially equalizing pressures therebetween but for preventing intermixing of said first and second liquids, said baffle means is vertically disposed in the chamber of said tank and further comprising first and second horizontally disposed baffle plates in said first and second compartments, respectively, to divide each compartment into a pair of sub-compartments and vent means extending through each of said baffle plates to communicate each pair of sub-compartments with each other.

9. The invention of claim 8 wherein said tank further comprises a filler tube having a pressure cap removably attached thereto for filling purposes, said baffle means extending partly into said filler tube.

10. The invention of claim 8 wherein said baffle means is vertically disposed in the chamber of said tank and comprises a passage formed through said baffle means adjacent the upper end thereof to communicate said first and second compartments.