Heating apparatus for vehicle, having heat-generating unit

• US 6,027,032 A
• Filed: 08/20/1997
• Issued: 02/22/2000
• Est. Priority Date: 08/21/1996
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation, Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Denso Corporation Kariya, Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Uchida, Goro, Kato, Yasushi, Aoki, Shinji, Morikawa, Toshio, Ito, Hajime, Ban, Takashi
• Primary Examiner(s): Bennett, Henry A.
• Assistant Examiner(s): Boles, Derek S.
• Application Number:
  US08/915,155
• Time in Patent Office: 916 Days
• Field of Search: 237/12.3 R, 237/12.3 B, 122/26, 126/247
• US Class Current: 237/12.30R
• CPC Class Codes: B60H 1/038 from the cooling liquid of the propulsion plant and from a viscous fluid heater
• CPC Class Codes: F01P 2060/18 Heater
• CPC Class Codes: F01P 3/20 Cooling circuits not specific to a single part of engine or machine F01P3/22 takes precedence
• CPC Class Codes: F24V 40/00 Production or use of heat resulting from internal friction of moving fluids or from friction between fluids and moving bodies

Abstract

According to the present invention, in a heating apparatus having a viscous heater using viscous fluid for heating cooling water, when an engine rotational speed is lower than a set rotational speed relative to a temperature of viscous fluid, a viscous clutch is turned on to transmit a rotational driving force of the engine to a rotor of the viscous heater. In this way, a shearing force is applied to the viscous fluid in the heat-generating chamber, and the circulating cooling water is heated by generated heat of the viscous fluid to improve the heating capacity. When the engine rotational speed is higher than the set rotational speed relative to a temperature of viscous fluid, a viscous clutch is not turned on. Therefore, the rotational driving force of the engine is not transmitted to the rotor of the viscous heater, so that the shearing force is not applied to the viscous fluid to prevent the oil temperature of the viscous fluid from increasing excessively higher than 200° C.

Claims

1. A heating apparatus for heating a passenger compartment of a vehicle having a water-cooled internal combustion engine, said heating apparatus comprising:

a heating heat exchanger for heating said passenger compartment by heat-exchanging between cooling water having cooled said water-cooled engine and air to be blown into said passenger compartment;

a heat-generating unit using a shearing force, said heat-generating unit having a rotor which rotates when a rotational driving force of said engine is applied thereto, a heat-generating chamber for sealing therein viscous fluid which generates heat when a shearing force generated by a rotational driving force of said rotor is applied thereto, and a cooling water passage in which the cooling water circulates between said engine and said heating heat exchanger, said heat-generating unit heating the cooling water to be supplied to said heating heat exchanger by generated heat of the viscous fluid in said heat-generating chamber;

shearing state switching means for switching a shearing state of the viscous fluid by the rotational driving force from said engine to said rotor;

detecting means for detecting a rotational speed of said rotor; and

a heating control unit for controlling said shearing state switching means to reduce loads of said engine when the rotational speed of said rotor detected by said detecting means is more than a predetermined value.

2. A heating apparatus according to claim 1, wherein said heating control unit controls said shearing state switching means to minimize loads of said engine when the rotational speed of said rotor detected by said detecting means is more than the predetermined value.

3. A heating apparatus according to claim 1, wherein said shearing state switching means is a driving force transmitting unit for transmitting the rotational driving force of said engine to said rotor.

4. A heating apparatus according to claim 3, wherein,

said driving force transmitting unit includes a belt transmitting mechanism for transmitting the rotational driving force of said engine to a rotating body of an auxiliary equipment for said engine with said rotor, and

said detecting means is a rotational speed sensor for detecting a rotational speed of said rotating body.

5. A heating apparatus according to claim 1, wherein said detecting means is an engine rotation speed sensor for detecting a rotational speed of said engine.

6. A heating apparatus according to claim 1, wherein,

said driving force transmitting unit includes a clutch for intermitting a transmission of the rotational driving force from said engine to said rotor of said heat-generating unit, and

said detecting means is a rotational speed sensor for detecting a rotational speed of said clutch.

7. A heating apparatus according to claim 1, further comprising:

a cooling water temperature sensor for detecting a temperature of the cooling water;

wherein said heating control unit controls said shearing state switching means in accordance with the temperature of the cooling water, detected by said cooling water temperature sensor.

8. A heating apparatus for heating a passenger compartment of a vehicle having a water-cooled internal combustion engine, said heating apparatus comprising:

a heating heat exchanger for heating said passenger compartment by heat-exchanging between cooling water having cooled said water-cooled engine and air to be blown into said passenger compartment;

a heat-generating unit using a shearing force, said heat-generating unit having a rotor which rotates when a rotational driving force of said engine is applied thereto, a heat-generating chamber for sealing therein viscous fluid which generates heat when a shearing force generated by a rotational driving force of said rotor is applied thereto, and a cooling water passage in which the cooling water circulates between said engine and said heating heat exchanger, said heat-generating unit heating the cooling water to be supplied to said heating heat exchanger by generated heat of the viscous fluid in said heat-generating chamber;

shearing state switching means for switching a shearing state of the viscous fluid by the rotational driving force from said engine to said rotor;

detecting means for detecting a temperature of the viscous fluid in said heat-generating chamber; and

a heating control unit for controlling said shearing state switching means to reduce loads of said engine when the temperature of the viscous fluid is higher than a predetermined value.

9. A heating apparatus according to claim 8, wherein said heating control unit controls said shearing state switching means to minimize loads of said engine when the temperature of the viscous fluid is higher than the predetermined value.

10. A heating apparatus according to claim 8, wherein said shearing state switching means is a driving force transmitting unit for transmitting the rotational driving force of said engine to said rotor.

11. A heating apparatus according to claim 10, wherein,

said driving force transmitting unit includes a clutch for intermitting a transmission of the rotational driving force from said engine to said rotor of said heat-generating unit.

12. A heating apparatus for heating a passenger compartment of a vehicle having a watercooled internal combustion engine, said heating apparatus comprising:

a heating heat exchanger for heating said passenger compartment by heat-exchanging between cooling water having cooled said water-cooled engine and air to be blown into said passenger compartment;

a heat-generating unit using a shearing force, said heat-generating unit having a rotor which rotates when a rotational driving force of said engine is applied thereto, a heat-generating chamber for sealing therein viscous fluid which generates heat when a shearing force generated by a rotational driving force of said rotor is applied thereto, and a cooling water passage in which the cooling water circulates between said engine and said heating heat exchanger, said heat-generating unit heating the cooling water to be supplied to said heating heat exchanger by generated heat of the viscous fluid in said heat-generating chamber;

shearing state switching means for switching a shearing state of the viscous fluid by the rotational driving force from said engine to said rotor;

rotational speed detecting means for detecting a rotational speed of said rotor;

a heating control unit for controlling said shearing state switching means to stop applying the rotational driving force of said engine to said rotor when the rotational speed of said rotor is more than a predetermined value.