Thermostat

• US 6,457,652 B1
• Filed: 01/27/2000
• Issued: 10/01/2002
• Est. Priority Date: 01/27/1999
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company), Nippon Thermostat Co., Ltd.
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company), Nippon Thermostat Co., Ltd.
• Inventors: Aburakawa, Masahiro, Fukamachi, Masatoshi, Iwaki, Takahiro
• Primary Examiner(s): Tapolcai, William E.
• Application Number:
  US09/492,450
• Time in Patent Office: 978 Days
• Field of Search: 236/34.5, 236/34
• US Class Current: 236/34.5
• CPC Class Codes: F01P 7/16 by thermostatic control
• CPC Class Codes: G05D 23/1333 measuring the temperature of incoming fluid

Abstract

A thermostat 1 which placed in a cooling fluid channel of an internal combustion engine and which controls the flow of a cooling fluid within the cooling fluid channel depending upon a change in the temperature is disclosed. The thermostat has a cylindrical valve body 17 having an inlet opening 17a, an outlet opening 17b, and a bypass opening 17g formed on the circumference surface thereof and fixed at the position where the inlet opening and the outlet opening are communicated with the cooling fluid channel, a fluid channel area FA which communicates the inlet opening with the outlet opening, a thermo valve 7 having a piston 16 which goes forward and backward according to the actions of a thermal expansion element 15a a spring member 6 at one side, and having a valve element 12 which moves forward and backward across the fluid channel area whereby the thermo valve slides within the valve body due to the movement of the piston, and a bypass valve element 20 which stands parallel to the movement of the piston at another side of the thermo valve and which can be inserted into a bypass channel. The valve element opens or closes the inlet opening and the outlet opening due to the movement of the bypass valve element together with the piston to communicate or block said fluid channel area, and the valve element opens or closes the bypass opening and the bypass valve element opens or closes the bypass channel to communicate or block the bypass opening and the bypass channel.

Claims

1. A thermostat comprising:

a valve body having an inlet opening, an outlet opening and a bypass opening formed on a circumference surface thereof and a fluid channel area communicating said inlet opening with said outlet opening within said valve body, said inlet opening and said outlet opening communicating with a cooling fluid channel, said bypass opening communicating to said cooling fluid channel and a bypass channel within said valve body;

a thermo valve provided in said valve body and configured to open and close communication between said inlet opening and said outlet opening and communication between said bypass opening and said bypass channel based on expansion and reduction of a thermal expansion element configured to thermally expand and reduce volume thereof;

a spring provided in said valve body and configured to urge said thermal expansion element to be compressed; and

a joint cover configured to cover an end portion of said valve body and communicating with said bypass channel,

wherein said joint cover has a bypass channel portion communicating with said bypass channel; and

wherein said bypass valve is engaged with said bypass channel portion and configured to slide along said bypass channel portion based on the movement of said piston to open and close said communication between said bypass opening and said bypass channel.

2. The thermostat of claim 1, wherein said thermo valve comprises:

a piston configured to move based on said expansion and reduction of said thermal expansion element;

a valve element configured to open and close said communication between said inlet opening and said outlet opening based on movement of said piston; and

a bypass valve configured to open and close said communication between said bypass channel and said bypass opening based on said movement of said piston.

3. The thermostat of claim 2, wherein said thermo valve has said valve element on an one end portion and said bypass valve on an opposite end portion.

4. The thermostat of claim 1, wherein

said thermo valve is configured to open said communication between said inlet opening and said outlet opening and close said communication between said bypass opening and said bypass channel when said thermal expansion element thermally expands volume thereof;

and

said thermo valve is configured to close said communication between said inlet opening and said outlet opening and open said communication between said bypass opening and said bypass channel when said thermal expansion element thermally reduces volume thereof.

5. The thermostat of claim 1, wherein said thermally expandable element comprises a wax.

6. The thermostat of claim 2, wherein said bypass valve is configured to plug and unplug said bypass channel to open and close said communication between said bypass opening and said bypass channel.

7. The thermostat of claim 1, wherein said joint cover is configured to engage with said valve body by screwing.

8. The thermostat of claim 1, wherein said joint cover is configured to cover an opening from which said thermostat is inserted.

9. The thermostat of claim 1, wherein:

said bypass valve has a hollow portion inside said bypass valve and at least one bypass pore on an outer surface of said bypass valve;

said hollow portion is communicating with said bypass channel portion and said at least one bypass pore; and

said at least one bypass pore being configured to open and close said communication between said bypass opening and said bypass channel according to a position of said bypass valve.

10. An internal combustion engine comprising the thermostat of claim 1.

11. A vehicle comprising the thermostat of claim 1.

12. A cooling system comprising the thermostat of claim 1.