Controlling engine coolant flow and valve assembly therefor

• US 4,930,455 A
• Filed: 10/14/1988
• Issued: 06/05/1990
• Est. Priority Date: 07/07/1986
• Status: Expired due to Term

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Creed, Brian T., Bradshaw, Cyril E.
• Primary Examiner(s): Kamen, Noah P.
• Application Number:
  US07/258,098
• Time in Patent Office: 599 Days
• Field of Search: 123/41.02, 123/41.08, 123/41.09, 123/41.1, 237/12.3 B, 237/8 A, 251/129.05, 251/129.11, 251/358
• US Class Current: 123/41.1
• CPC Class Codes: B60H 1/00885 Controlling the flow of heating or cooling liquid, e.g. valves or pumps B60H1/00899 takes precedence; constructions of valves B60H1/00485
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2011/063 Cleaning F01P2011/061 takes precedence
• CPC Class Codes: F01P 2025/12 Cabin temperature
• CPC Class Codes: F01P 2025/13 Ambient temperature
• CPC Class Codes: F01P 2025/32 Engine outcoming fluid temperature
• CPC Class Codes: F01P 2060/08 Cabin heater
• CPC Class Codes: F01P 2070/00 Details
• CPC Class Codes: F01P 7/08 by cutting in or out of pumps
• CPC Class Codes: F01P 7/165 characterised by systems with two or more loops

Abstract

A motorized water valve of the butterfly-type having the motor case and gear reduction housing formed integrally with the valving chamber. The metal butterfly has elastomeric material formed thereover to provide improved sealing and prevent leakage when the valve is closed thereby enabling substantially shortened warm-up in thermostat application. The control system employs the valve at the engine block outlet to control coolant flow to the radiator in response to an electrical control signal based upon comparison of the sensed block temperature with a desired engine temperature. The control system also employs the valve to control coolant flow to the heater core in response to an electrical control signal based upon a comparison of sensed in-car temperature and a desired in-car temperature selectd by the driver. Heater core discharge air may also be sensed and included in the comparison to provide a control signal to permit automatic in-car temperature regulation. An additional control signal also be generated from the comparison to control heater blower speed control. The control system, upon cold engine starts, opens the radiator coolant valve fully for a short time to allow full flow to clean the valve and remove deposits, then returns to the closed position to continue engine warm-up. The control system may also employ an outside air temperature transducer to provide a signal used in the comparison to enable automatic regulation of desired engine coolant temperature.

Claims

1. A method of controlling coolant for through the heat exchanger circuit of an internal combustion engine comprising the steps of:

(a) channeling coolant flow from the engine through a valving passage to the coolant heat exchanger;

(b) providing a valve in said passage;

(c) sensing the coolant temperature in said engine;

(d) opening said valve upon cold engine start-up to permit substantially full flow therethrough for a brief interval comprising a small fraction of the engine warm-up period, for cleaning foreign particles from the valve seating surfaces, and returning said valve to a partially open position for continued warm-up; and

,

(e) modulating the position of said valve responsive to changes in said sensed temperature for controlling coolant flow to maintain normal engine operating temperature.

2. The method defined in claim 1, wherein the step of opening said valve for full flow upon cold engine start-up comprises substantially immediately opening said valve for full flow upon cold engine start-up.

3. The method defined in claim 1, wherein the step of sensing temperature includes the steps of generating an electrical signal indicative of changes in sensed temperature and providing a motor driver electrical signal therefrom;

and, said step of modulating includes the step of driving an electric motor responsive to said motor driver signal and moving said valve member with said motor.

4. The method defined in claim 1, wherein the step of providing a valve in said passage includes the step of pivoting an elastomer covered plate in said passage and balancing the fluid forces acting on said plate about the axis of said pivoting.

5. A system for controlling flow of coolant in a circuit comprising an internal combustion engine and a heat engine coolant to passenger compartment air in a vehicle, said system comprising:

(a) heat exchanger means having an inlet and an outlet which is connected to the engine for coolant flow therethrough;

(b) transducer means operative to sense temperature in the vehicle passenger compartment, said transducer means operative in response to said sensed temperature to provide an electrical temperature feedback signal;

(c) electrically actuatable valve means with the inlet thereof receiving heated coolant from the engine with the outlet of said valve means, said valve means having a housing means formed of plastic material and defining integrally therewith a flow passage, a motor cavity and a gear box with a stepper motor disposed in said cavity and speed reducer means having an output disposed in said gear box and driven by said stepper motor, said valve means including a rigid pivoted member movable by said speed reducer output between a closed position preventing flow thereover and an open position permitting coolant flow to said heat exchanger, said pivoted member having an elastomeric seating surface for preventing coolant leakage in the closed position;

(d) logic and power circuit means operable in response to said temperature feedback signal and a comparison thereof with a reference temperature to provide a valve actuation signal for actuating said stepper motor to position said valve member in a preselected position in response to said comparison and thereby control coolant flow for modulating said passenger compartment temperature at said reference temperature.

6. The control system defined in claim 5, wherein said heat exchanger comprises a passenger compartment heater core and said transducer means comprises an in-car air temperature sensor.

7. The control system defined in claim 5, wherein said valve means includes a reversible motor and speed reducing means for moving said pivoted member.

8. The control system defined in claim 5, wherein

(a) said heat exchanger means comprises a passenger compartment heater core;

(b) said transducer means comprises a passenger compartment air temperature sensor; and

,

(c) further comprising temperature select means operable upon actuation by a vehicle occupant to provide an electrical signal to said circuit means for providing said reference temperature.

9. The control system defined in claim 5, further comprising blower means for directing a flow of air across said heater core and plenum means for directing said air flow to the vehicle passenger compartment and wherein said transducer means includes a first thermistor disposed to sense the air temperature in said plenum means and a second thermistor disposed to sense in-car air temperature for providing said feedback signal.

10. A system for controlling flow of coolant in a circuit comprising an internal combustion engine and a heat exchanger for transferring heat from the engine coolant to ambient air said system comprising:

(a) heat exchanger means having an inlet and an outlet which is connected to the engine for coolant flow therethrough;

(b) transducer means operative to sense engine coolant jacket temperature, said transducer means operative in response to said sensed temperature to provide an electrical temperature feedback signal;

(c) electrically actuatable valve means with the inlet thereof receiving heated coolant from the engine with the outlet of said valve means discharging to the inlet of said heat exchanger means, said valve means having a housing means formed of plastic material and defining integrally therewith a flow passage, a motor cavity and a gear box with a stepper motor disposed in said cavity and speed reducer means having an output disposed in said gear box and driven by said stepper motor, said valve means including a rigid pivoted member movable by said speed reducer output between a closed position preventing flow thereover and an open position permitting coolant flow to said heat exchanger, said pivoted member having an elastomeric seating surface for preventing coolant leakage in the closed position;

(d) logic and power circuit means operable in response to said temperature feedback signal and a comparison thereof with a reference temperature to provide a valve actuation signal for actuating said stepper motor to position said valve member in a preselected position in response to said comparison and thereby control coolant flow for modulating said engine temperature at said reference temperature.

11. A system for controlling flow of coolant in a circuit comprising an internal combustion engine and a heat exchanger for transferring heat from the engine coolant to passenger compartment air in a vehicle, said system comprising:

(a) heat exchanger means having an inlet and an outlet which is connected to the engine for coolant flow therethrough;

(b) means for flowing air over said heat exchanger means and discharging same into the passenger compartment;

(c) transducer means operative to sense temperature of said discharging air closely adjacent said heat exchanger means, said transducer means operative in response to said sensed temperature to provide an electrical temperature feedback signal;

electrically actuatable valve means with the inlet thereof receiving heated coolant from the engine with the outlet of said valve means discharging to the inlet of said heat exchanger means, said valve means having a housing means formed of plastic material and defining integrally therewith a flow passage, a motor cavity and a gear box with a stepper motor disposed in said cavity and speed reducer means having an output disposed in said gear box and driven by said stepper motor, said valve means including a rigid pivoted member movable by said speed reducer output between a closed position preventing flow thereover and an open position permitting coolant flow to said heat exchanger, said pivoted member having an elastomeric seating surface for preventing coolant leakage in the closed position;

logic and power circuit means operable in response to said temperature feedback signal and a comparison thereof with a referenced temperature to provide a valve actuation signal for actuating said stepper motor to position said valve member in a preselected position in response to said comparison and thereby control coolant flow for modulating said discharging air at said reference temperature.

12. A method of controlling coolant flow between an internal combustion engine and an air heat exchanger comprising the steps of:

(a) providing an electrically operated valve in fluid series flow arrangement in the circuit of coolant flow between said engine and said heat exchanger;

(b) sensing the temperature of the coolant in said engine and providing an electrical signal representative of said sensed temperature; and

,

(c) comparing said sensed temperature signal with a reference temperature signal and generating a valve control signal and controlling the position of said valve to alter coolant flow for modulating engine temperature about said reference temperature; and

,

(d) opening said valve sufficiently to effect full flow for a small fraction of the cold engine warm-up interval and flushing said valve of foreign material.

13. An electrically actuated valve assembly for controlling flow of engine coolant, said valve assembly comprising:

(a) housing means formed of plastic material and integrally defining a coolant flow passage having an inlet and outlet, a motor casing and a gear box;

(b) a butterfly valving member disposed in said passage between said inlet and outlet, said valving member pivoted about an axis transverse to the direction of flow and operable for pivoted movement between a closed position of open positions permitting partial or full flow therethrough;

(c) a shaft extending through the wall of said housing into said passage and journalled therein for rotation with respect thereto, said shaft having the end portion thereof external to said passage including indicator means extending in a direction generally parallel to said butterfly member, said shaft having said valving member attached thereto for providing said pivoted movement upon rotation of said shaft;

(d) stepper motor means including speed reducer means received in said casing, said speed reducer means received in said gear box having power output shaft means with torque coupling means provided thereon, said torque coupling means engaging said external end portion of said shaft for effecting rotation thereof upon said stepper motor being energized by an electrical control signal.

14. The valve assembly defined in claim 13, wherein said valving member has said shaft member attached to the geometric center of pressure thereof to provide balanced pressure force moments about said pivot axis.

15. The valve assembly defined in claim 13, wherein said output shaft means comprises a gear hub and said torque coupling means comprises a slot formed in the end of said gear hub.

16. The valve assembly defined in claim 13, wherein said housing means is formed of plastic material and said inlet comprises a metal flange adapted for connection directly to an engine coolant output port, said metal flange connected to said plastic housing with means for sealing therearound.

17. The valve assembly defined in claim 13, wherein said housing means is formed of plastic material and further comprising a metal flange adapted for direct connection to an engine coolant outlet and secured to said housing inlet by a clamping band.

18. The valve assembly defined in claim 13, wherein said inlet includes a flanged metal member adapted for connection directly to the coolant outlet port on an engine.

19. The valve assembly defined in claim 13, wherein said housing is formed of plastic material and has a metal flange provided at the inlet, which is adapted for direct connection to the coolant outlet port of an engine.

20. The valve assembly defined in claim 19, wherein said exterior end portion of said shaft extends outwardly of said coupling means and in a direction parallel to said butterfly providing a visible indication of the position of said valving member in said passage.