Electrical system for an internal combustion engine

• US 6,196,177 B1
• Filed: 03/22/1999
• Issued: 03/06/2001
• Est. Priority Date: 03/22/1999
• Status: Expired due to Term

• Current Assignee: Detroit Diesel Corporation (Mercedes-Benz Group AG)
• Original Assignee: Detroit Diesel Corporation (Mercedes-Benz Group AG)
• Inventors: VanderBok, Arnold J.
• Primary Examiner(s): Dolinar, Andrew M.
• Assistant Examiner(s): HUYNH, HAI H
• Application Number:
  US09/274,002
• Time in Patent Office: 715 Days
• Field of Search: 123/196.AB, 123/142.5 E, 123/41.14, 123/145.R, 123/145.A, 237/12.3 R, 315/209.T, 315/209.SC, 219/202, 219/205, 219/208, 219/209
• US Class Current: 123/142.50E
• CPC Class Codes: F01M 5/021 by heating

Abstract

An improved electrical system for internal combustion engines which transfers electrically generated energy from the alternator to heat engine fluids, such as the coolant and the oil, thereby reducing engine warm up time, and/or exhaust emissions and/or fuel consumption.

Claims

1. In an electrical system of an internal combustion engine having an electronic control unit (ECU), said electrical system comprising a battery power source;

and alternator connected to said battery for recharging said battery;

a starter motor powered by said battery source;

an ignition switch controlling current flow from said battery power source to said starter motor, said ECU having memory and connected to said power source;

the improvement comprising a first sensor to sense engine oil temperature, and a second sensor to sense coolant temperature, each sensor in communication with said ECU, and separate current supply lines from the alternator with separate resistance in each line in heat transfer relation with a respective engine fluid each said line having a relay controlled by the ECU to control the flow of current from the alternator to the resistance in response to sensor input to the ECU.

2. The improvement of claim 1, wherein said resistance is formed of a material having a high thermal conductivity.

3. The improvement of claim 1, wherein said internal combustion engine is a diesel engine.

4. The improvement of claim 1, wherein said electrical system is associated with an engine cooling system that includes a coolant passage in the engine;

and a well extending within said engine into said coolant passage;

said resistance comprising a resistor located in said well, whereby electrically generated heat is transferred from said resistor to the coolant in said passage.

5. The improvement of claim 1, wherein said electrical system is associated with an engine oil system that includes an oil reservoir in the engine;

and a well extending within said engine into said oil reservoir;

said resistance comprising a resistor located in said well, whereby electrically generated heat is transferred from said resistor to the oil in said reservoir.

6. The improvement of claim 1, wherein said ECU varies the engine speed and varies the alternator output in response to sensor input from said temperature sensors.

7. In an electrical system of an internal combustion engine having an electronic control unit (ECU), said electrical system comprising a battery power source;

an alternator connected to said battery for recharging said battery;

a starter motor powered by said battery source;

an ignition switch controlling current flow from said battery power source to said starter motor, said ECU having memory and connected to said power source;

the improvement comprising a first sensor connected to said ECU for sensing the temperature of an engine oil, and a second sensor connected to said ECU for sensing the temperature of an engine coolant;

a first resistance in a first current supply line from the alternator in heat transfer relation with said oil; and

a second resistance in a second current supply line from the alternator in heat transfer relation with said coolant;

each said current supply line having a relay controlled by the ECU to control the flow of current from the alternator to the resistance in response to sensor input to the ECU.

8. The improvement of claim 7, wherein each said resistance is formed of a material having a high thermal conductivity.

9. The improvement of claim 7, wherein said internal combustion engine is a diesel engine.

10. The improvement of claim 7, wherein said electrical system is associated with an engine cooling system that includes a coolant passage in the engine;

and a well extending within said engine into said coolant passage;

said first resistance comprising a resistor located in said well, whereby electrically generated heat is transferred from said resistor to the coolant in said passage.

11. The improvement of claim 7, wherein said electrical system is associated with an engine oil system that includes an oil reservoir in the engine;

and a well extending within said engine into said oil reservoir;

said second resistance comprising a resistor located in said well, whereby electrically generated heat is transferred from said resistor to the oil in said reservoir.

12. The improvement of claim 7, wherein said ECU varies the engine speed and varies the alternator power output in response to sensor input from said temperature sensors.

13. A method for controlling the engine speed of an internal combustion engine, having an electronic control unit (ECU) with memory for controlling the engine, an electrical system comprising a battery power source;

an alternator connected to said battery for recharging said battery;

a starter motor powered by said battery source;

an ignition switch controlling current flow from said battery power source to said starter motor, said ECU connected to said power source and having at least one sensor connected to said ECU for sensing the temperature of engine fluids including engine oil and engine coolant, and at least one resistance in a separate current supply line from the alternator in heat transfer relation with each said engine fluid;

each said current supply line having a relay controlled by the ECU to control the flow of current from the alternator to each said resistance in response to sensor input to the ECU;

the method comprising;

(a) starting the engine;

(b) sensing the temperature of at engine oil and engine coolant;

(c) supplying current from the alternator to the resistance;

(d) determining whether the vehicle is speed is greater than 0;

(e) sensing engine speed;

(f) controlling engine speed;

(f) ceasing the flow of current from the alternator to the resistance when a sensed temperature has reached a predetermined temperature.

14. The method of claim 13, wherein engine speed is controlled by controlling fuel delivery to the engine.

15. The method of claim 13, wherein current is supplied when the ECU closes a relay switch in the electrical line from the alternator to the resistance.

16. The method of claim 13, wherein current supply to resistance is ceased by the ECU opening a relay switch in response to sensed temperature.

17. The method of claim 13, further including the step of decreasing engine speed when an engine fluid has reached the predetermined temperature.