GB2241301A

GB2241301A - Thermostatically controlled valve for engine cooling system

Info

Publication number: GB2241301A
Application number: GB9004115A
Authority: GB
Inventors: Anthony Philip Breeden; Richard Thomas Scott
Original assignee: Western Thomson Controls Ltd
Current assignee: Western Thomson Controls Ltd
Priority date: 1990-02-23
Filing date: 1990-02-23
Publication date: 1991-08-28
Also published as: GB9004115D0

Abstract

A thermostatically controlled valve for an engine cooling system, comprises a housing (1) having a port (7) in a side wall thereof. A sleeve (2) is slidably mounted in said housing and normally engages a sealing ring (3) to close said port (7) from communication with a fluid path (4) defined by the housing (1) and the sleeve (2) and extending between an inlet (5) at one end thereof and an outlet (6) at the other end thereof. An expansible thermostatic element (8) mounted in the fluid path (4) and connected to the housing (1) and sleeve (2) acts to move the sleeve (2) relative to the housing (1) to open communication between the port (7) and the fluid path (4) when the thermostatic element (8) senses a predetermined temperature. Means (2a, 2b, 12) enable fluid from the port (7) to flow around at least a portion of the expansible thermostatic element (8) when communication between the port (7) and the fluid path (4) is closed. <IMAGE>

Description

THERMOSTATICALLY CONTROLLED VALVE FOR ENGINE COOLING SYSTEM This invention relates to thermostatically controlled valves for engine cooling systems, e.g., the cooling systems of motor vehicle engines.

To ensure that a vehicle engine reaches operating temperature as quickly as possible in cold weather and to provide heat to the passenger compartment as quickly as possible, it is known in vehicle engine cooling systems to provide a thermostatic valve controlled bypass whereby liquid coolant can circulate through the engine but not through the radiator until such time as the thermostat valve opens to allow the cooling liquid to pass through the radiator.To ensure that the vehicle engine is operating at or near its optimum temperature and to ensure maximum heat to the passenger compartment in cold weather, it is advantageous if the thermostat of the thermostatically controlled valve senses the temperature of the cooling liquid in the radiator as well as the temperature of the cooling liquid in the bypass and it is the object of the present invention to provide a thermostatically controlled valve suitable for this purpose.

The present invention provides a thermostatically controlled valve for an engine cooling system, comprising a housing having a port in a side wall thereof, a sleeve slidably mounted in said housing and normally closing said port, said housing and said sleeve defining a fluid path between an inlet at one end thereof and an outlet at the other end thereof, an expansible thermostatic element mounted in said fluid path and connected to said housing and said sleeve whereby said sleeve will be moved relative to said housing to open communication between said port and said fluid path when fluid in said fluid path reaches a predetermined temperature, and means whereby fluid from said port can contact rund at least a portion of said expansible thermostatic element when communication between said port and said fluid path is closed.

The valve may comprise a sealing ring mounted in said housing and providing a seating for an end of said sleeve. Spider means may extend inwardly of said sealing ring and be connected to said thermostatic element.

The thermostatic element may comprise a bulb containing an expansible medium, e.g. an expansible liquid, solid or gaseous medium such as an expansible wax, a piston slidable in the bulb and a piston rod connected to said piston and extending outwardly of said bulb.

Said sleeve may be movable relative to said housing against a spring bias.

According to one embodiment of the invention, said sleeve comprises first and second sleeve parts which are spaced apart and which combine to close said port, said sleeve parts each comprising a peripheral wall and an end wall connected to said thermostatic element, and passage means extending between said end walls and forming part of said fluid path, said sleeve parts and said passage means defining a chamber surrounding a portion of the thermostatic element, e.g. surrounding a portion of said bulb, and communicating with said port. Said passage means may be provided by at least one tube or conduit connecting opposed apertures in said end walls.

According to another embodiment of the invention, an annular chamber is provided around a portion of said thermostatic element and said thermostatic element is supported in said housing by spider means comprising hollow spider arms which communicate said annular chamber with said port.

The thermostatically controlled valve of the present invention may be fitted in an automobile cooling system with said inlet connected to an engine coolant bypass, said outlet connected to the coolant pump and said port connected to the coolant radiator.

The invention will be more particularly described with reference to the accompanying drawings, in which: Figure 1 is a sectional elevation of a thermostatically controlled valve according to one embodiment of the present invention, and Figure 2 is a sectional elevation of another embodiment of a thermostatically controlled valve according to the invention.

Referring to Figure 1 it will be seen that the thermostatically controlled valve illustrated therein comprises a housing 1 in which is slidably mounted a sleeve 2 one end of which seats against a sealing ring 3 mounted in the housing 1. The housing 1 and sleeve 2 define a fluid path 4 between an inlet 5 from an engine coolant bypass and an outlet 6 to the engine coolant pump. A port 7 in the housing 1 is normally closed from communication with the fluid path 4 by the sleeve 2.

An expansible thermostatic element 8 comprising a bulb 9 containing an expansible medium and a piston (not shown) having a piston rod 10 extending outwardly of the bulb 9 is mounted in the fluid path 4 on spider means 11 extending inwardly of the sealing ring 3.

Sleeve 2 is formed in two parts 2a, 2b which are spaced apart and which each comprise a peripheral wall 2c and an end wall 2d. Sleeve parts 2a, 2b are connected together by tubes or conduits 12 which extend between apertures in the end walls 2d thereof and are secured thereto, the tubes or conduits 12 defining passages 13 which form part of the fluid path 4. The sleeve parts 2a, 2b and the tubes or conduits 12 define a chamber 14 which surrounds a portion of the thermostatic element 8 and which, when the valve is closed as shown, is isolated from the fluid path 4 but is in communication with the port 7. In this way the bulb 9 is subject to the temperature of the coolant liquid from the radiator in the port 7.When the thermostatic element senses that the coolant liquid is at a predetermined temperature, it will expand and cause the sleeve 2 to move away from its seating engagement with the sealing ring 3 to open communication between the port 7 and the fluid path 4 so that the coolant liquid will then circulate through the radiator.

Sleeve 2 is biased into engagement with sealing ring 3 by a coil spring 15 mounted within a spring cage 16 and bearing at one end on spider means 11 and at the other end on an inturned end portion 16a of spring cage 16. A balancing spring 25 is provided between a washer 26 which abuts the bulb 9 and an inturned flange 27 of the spider means 11. Cage 16 extends through slots lia in the spider means 11 so as to be movable relative thereto.

Inturned flange 27 of spider means 11 is secured to a stop member 28 secured to the free end of the piston rod 10. A sealing ring 29 is provided between housing 1 and the sleeve 2.

In the embodiment shown in Figure 2, in which like parts have been given like reference numerals, the spider means comprises spider arms 11 which extend between the sealing ring 3 and an inner hollow ring 17 which extends around the bulb 9 and defines an annular chamber 18 surrounding a portion of the bulb 9. Spider arms 11 are hollow and have passages 19 extending therethrough which communicate the annular chamber 18 with the port 7 by way of apertures 20 in the sealing ring 3. In this embodiment the sleeve 2 is formed in one piece and is connected to the thermostatic element 8 by spider arms 21.

Claims

1. A thermostatically controlled valve for an engine cooling system, comprising a housing having a port in a side wall thereof, a sleeve slidably mounted in said housing and normally closing said port, said housing and said sleeve defining a fluid path between an inlet at one end thereof and an outlet at the other end thereof, an expansible thermostatic element mounted in said fluid path and connected to said housing and said sleeve whereby said sleeve will be moved relative to said housing to open communication between said port and said fluid path when said thermostatic element senses a predetermined temperature, and means whereby fluid from said port can contact at least a portion of said expansible thermostatic element when communication between said port and said fluid path is closed.

2. A valve according to claim 1, comprising a sealing ring mounted in said housing and providing a seating for an end of said sleeve.

3. A valve according to claim 2, wherein spider means extends inwardly of said sealing ring and is connected to said thermostatic element.

4. A valve according to claim 1, 2 or 3, wherein said thermostatic element comprises a bulb containing an expansible medium, a piston slidable in said bulb and a piston rod connected to said piston and extending outwardly of said bulb.

5. A valve according to any one of the preceding claims, wherein said sleeve is movable relative to said housing against a spring bias.

6. A valve according to any one of the preceding claims, wherein said sleeve comprises first and second sleeve parts which are spaced apart and which combine to close said port, said sleeve parts each comprising a peripheral wall and an end wall connected to said thermostatic element, and passage means extending between said end walls and forming part of said fluid path, said sleeve parts and said passage means defining a chamber surrounding a portion of the thermostatic element and communicating with said port.

7. A valve according to claim 6, wherein said passage means comprises at least one tube or conduit connecting opposed apertures in said end walls.

8. A valve according to any one of claims 1 to 5, wherein an annular chamber is provided around a portion of said thermostatic element and said thermostatic element is supported in said housing by spider means comprising hollow spider arms which communicate said annular chamber with said port.

9. A valve according to any one of the preceding claims, when fitted in an automobile cooling system with said inlet connected to an engine coolant bypass, said outlet connected to the coolant pump and said port connected to the coolant radiator.

10. A thermostatically controlled valve for an engine cooling system, substantially as herein described with reference to Figure 1 or Figures 2 to 4 of the accompanying drawings.