Cooling system for automotive engine or the like

• US 4,545,335 A
• Filed: 04/20/1984
• Issued: 10/08/1985
• Est. Priority Date: 05/19/1983
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Hayashi, Yoshimasa
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Application Number:
  US06/602,451
• Time in Patent Office: 536 Days
• Field of Search: 123/41.02, 123/41.08, 123/41.1, 123/41.2, 123/41.21, 123/41.24, 123/41.27, 123/41.51, 123/41.54
• US Class Current: 123/41.27
• 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 11/18 concerning coolant pressure, coolant flow, or liquid-coolant level
• CPC Class Codes: F01P 3/2285 Closed cycles with condenser and feed pump
• CPC Class Codes: F01P 7/14 the coolant being liquid

Abstract

The present invention features an arrangement wherein in order to prevent atmospheric air (or the like) from entering the cooling system of an engine wherein the coolant is boiled and the vapor used as a vehicle for removing heat from the engine, upon the engine being stopped or the temperature of the system falling below a predetermined level, the cooling system is filled with liquid coolant under the influence of the sub-atmospheric pressure which tends to develop under such conditions. Additionally, the coolant can be pumped in, in the event that some air has entered or remains in either of the coolant jacket or radiator associated therewith, to displace said non-condensible matter out of the system and thus completely obviate any tendancy for which would otherwise tend to produce a heat exchange reducing "embolism" to occur in the radiator conduiting.

Claims

1. In an internal combustion engine having a combustion chamber

a coolant jacket into which coolant is introduced in liquid form and maintained at a level above said combustion chamber, said liquid coolant being permitted to boil;

a radiator means for condensing the gaseous coolant generated by the boiling of said liquid coolant in said coolant jacket;

a reservoir which communicates with one of said coolant jacket and said radiator, said reservoir being arranged to store coolant therein; and

a control means for normally blocking communication between said reservoir and said one of said coolant jacket and said radiator means and for establishing fluid communication therebetween when one of the pressure and temperature within said coolant jacket is below a predetermined level.

3. An internal combustion engine as claimed in claim 1, further comprising:

a temperature sensor for sensing the temperature of the coolant in said coolant jacket.

2. An internal combustion engine, comprising:

a coolant jacket into which coolant is introduced in liquid form and maintained at a level above said combustion chamber, said liquid coolant being permitted to boil;

a radiator for condensing the gaseous coolant generated by the boiling of said liquid coolant in said coolant jacket;

a reservoir which communicates with one of said coolant jacket and said radiator, said reservoir being arranged to store coolant therein; and

a control arrangement for normally blocking communication between said reservoir and said one of said coolant jacket and said radiator and for establishing fluid communication therebetween when one of the pressure and temperature within said coolant jacket is below a predetermined level;

a first level sensor disposed in said coolant jacket at said level higher than said combustion chamber;

a pump disposed in a return conduit leading from said radiator to said coolant jacket for returning condensed coolant from said radiator to said coolant jacket, said pump being responsive to the output of said first level sensor in a manner to maintain the level of liquid coolant at said level higher than said combustion chamber.

4. An internal combustion engine as claimed in claim 2, wherein said control arrangement comprises a first valve for controlling fluid communication between said reservoir and one of said coolant jacket and said radiator.

5. An internal combustion engine as claimed in claim 4, further comprising a second level sensor disposed at the bottom of said radiator.

6. An internal combustion engine as claimed in claim 5, wherein said control arrangement is responsive to the stoppage of said engine in a manner to open said first valve.

7. An internal combustion engine as claimed in claim 6, wherein said control arrangement is responsive to the starting of said engine and to the ouput of said second level sensor for closing said first valve.

8. An internal combustion engine as claimed in claim 5, further comprising:

a third level sensor disposed in one of said coolant jacket and said radiator and located at a level whereat it is immersed in liquid coolant only when said coolant jacket and said radiator are completely filled with liquid coolant;

a second valve which controls fluid communication between said reservoir and one of said coolant jacket and radiator, said second valve being disposed in an overflow conduit which leads from a location in close proximity of said third sensor to said reservoir; and

a third valve disposed in a supply conduit which leads from said reservoir to said return conduit, said supply conduit communicating with said return conduit at a location upstream of said pump;

said control arrangement being arranged to open and close said first, second and third valves and operate said pump in response to the outputs of said third level sensor and said temperature sensor in a manner to fill said coolant jacket and radiator with liquid coolant from said reservoir until said third sensor is immersed therein and thus displace any non-condensible matter out through said overflow conduit and said second valve to said reservoir, when the temperature within said coolant jacket is at a level at which said radiator and coolant jacket should be completely filled with liquid coolant.

9. An internal combustion engine as claimed in claim 4, further comprising a manually operable valve between said first valve and said reservoir for facilitating the adjustment of the level of coolant in said coolant jacket and in said reservoir.

10. An internal combustion engine as claimed in claim 2, wherein said control arrangement comprises:

a induction conduit arrangement which permits said pump to induct coolant from said reservoir and positively pump same into said coolant jacket when non-condensible matter tends to contaminate the coolant jacket and radiator; and

an overflow conduit arrangement which permits excess coolant pumped into said coolant jacket to overflow back to said reservoir and purge any contaminating non-condensible matter out of said coolant jacket and radiator.

11. An internal combustion engine as claimed in claim 2, further comprising:

a load sensor for sensing the load on said engine;

an engine speed sensor for sensing the rotational speed of said engine; and

a device for controlling the amount of heat removed from said radiator,

said control arrangement being arranged to be responsive to said load and engine speed sensors for controlling said device in a manner to maintain a first predetermined temperature in said coolant jacket when said engine is operating under a first set of load and engine speed conditions and a second predetermined temperature when said engine is operating under a second set of load and engine speed conditions.

12. An internal combustion engine as claimed in claim 11, wherein said device is a fan which is intermittently energized.

13. A method of operating an internal combustion engine having a combustion chamber comprising the steps of:

introducing coolant into a coolant jacket formed in said engine in a liquid form;

using said liquid coolant to absorb heat produced by said engine and converting said liquid coolant into its gaseous form;

condensing the gaseous coolant generated in said coolant jacket in a radiator;

storing a predetermined amount of coolant in a reservoir;

introducing the coolant stored in said reservoir into said coolant jacket and radiator to fill same when one of the pressure and temperature in said radiator and coolant jacket tend to fall below a first predetermined level.

14. A method as claimed in claim 13, further comprising the steps of:

sensing the level of liquid coolant in said coolant at a first level higher than said combustion chamber;

pumping condensed coolant from said radiator into said coolant jacket to maintain the level of said liquid at said first level.

15. A method as claimed in claim 14, further comprising the steps of:

inducting coolant from said reservoir and pumping same into said coolant jacket when non condensible matter tends to contaminate said radiator and coolant jacket to fill same; and

permitting excess coolant pumped into said coolant jacket to overflow back to said reservoir in a manner to purge any non-condensible matter out of said coolant jacket and radiator.

16. A method as claimed in claim 14, further comprising the steps of:

sensing the level of coolant at a second level proximate the bottom of said radiator;

cutting off connection between said reservoir and said coolant jacket and radiator when the temperature of the coolant within said coolant jacket is above said first predetermined temperature and said the level of coolant in said radiator is at said second predetermined level.

17. A method as claimed in claim 13, further comprising the step of sensing the temperature of said coolant in said coolant jacket.

18. A method as claimed in claim 13, further comprising the steps of:

sensing the load on said engine;

sensing the engine speed of said engine;

controlling the amount of heat removed from said radiator in a manner to maintain a first predetermined temperature in said coolant jacket when said engine is operating under a first set of load and engine speed conditions, and a second predetermined temperature when said engine is operating under a second set of load and engine speed conditions.

19. A method as claimed in claim 13, further comprising the steps of:

sensing the level of coolant at a third level to which liquid coolant rises only when said radiator and said coolant jacket are completely filled with liquid coolant; and

pumping liquid coolant from said reservoir into said coolant jacket and radiator when the temperature of said liquid coolant is at a level at which said coolant jacket and radiator should be filled with liquid coolant.

20. A method of operating an internal combustion engine having a combustion chamber comprising the steps of:

introducing coolant into a coolant jacket formed in said engine, in a liquid form;

using said liquid coolant to absorb heat produced by said engine and converting said liquid coolant into its gaseous form;

condensing the gaseous coolant generated in said coolant jacket in a radiator;

storing a predetermined amount of coolant in a reservoir; and

introducing the coolant stored in said reservoir into said coolant jacket and radiator when one of the pressure and temperature in said radiator and coolant jacket is below a first predetermined level.