Low Pressure Drop Thermal By-Pass Valve

• US 20110005741A1
• Filed: 07/09/2009
• Published: 01/13/2011
• Est. Priority Date: 07/09/2009
• Status: Active Grant

• Current Assignee: Dana Canada Corporation
• Original Assignee: Dana Canada Corporation
• Inventors: Sheppard, Jeffrey Owen
• Granted Patent: US 8,991,719 B2
• Time in Patent Office: Days
• US Class Current: 165/297
• CPC Class Codes: F01M 5/007 Thermostatic control
• CPC Class Codes: F16H 57/0413 Controlled cooling or heating of lubricant; Temperature control therefor
• CPC Class Codes: G05D 23/022 the sensing element being placed within a regulating fluid flow
• CPC Class Codes: G05D 23/1333 measuring the temperature of incoming fluid

Abstract

A thermal by-pass valve for a heat exchange circuit includes a housing forming a chamber and a by-pass valve port surrounded by a valve seat. The valve port is located between first and second sections of the chamber. First and second oil ports open into the first section. At least a third port opens into the second section. A thermally sensitive actuator is mounted in the first section and has a body and a piston located at one end. The body is movable in the chamber in response to extension of the piston. A valve member is operably mounted on the body and is movable by extension of the piston. A spacer projects from and is connected to the body and forms a passage through which the piston extends. The spacer acts to maintain the adjacent end of the actuator body at least the length of the passage away from an end of the chamber. The spacer can have a valve portion to close a further valve port.

Claims

1. A thermal by-pass valve for a heat exchange circuit, comprising:

a valve housing forming a valve chamber and having a first port for an oil supply line, a second port for an oil return line, a third port for a heat exchanger supply line and a fourth port for a heat exchanger return line, said first, second, third and fourth ports communicating with said chamber, and further having a by-pass valve port surrounded by a primary valve seat, said valve port being located in said chamber and providing fluid communication between said first and second ports when said valve port is open;

a thermally sensitive actuator including an actuator body having a shaft section and a movable piston extending from one end of said actuator body, said actuator being mounted in said chamber and movable therein in response to extension or retraction of said piston, said piston being extendible in order to engage said housing at or near one end of said chamber;

a valve member mounted on said shaft section and movable by extension of said piston from a first position where said valve port is open to a second position wherein said valve port is closed by said valve member sealingly engaging said valve seat;

a return spring mounted in said housing and having one spring end engaging said shaft section so as to bias said shaft section away from said valve seat and to move said actuator away from said valve seat upon retraction of said piston; and

a spacer member projecting from and connected to said one end of the actuator body and coaxial with said piston, said spacer member forming a piston-receiving passage into which said piston extends during use of the by-pass valve, said piston being slidable in said passage,

wherein said passage has a length and, during use of said valve, said spacer member acts to maintain said one end of the actuator body at least said length of the passage away from said one end of the chamber.

2. A thermal by-pass valve according to claim 1 wherein said actuator has an enlarged head section at said one end of the actuator, said head section having a diameter greater than diameter of said shaft section, and said valve housing has a further valve port located between said second port and said fourth port, and said spacer member is movable by extension of said piston from a closed position where said further valve port is closed by the spacer member to a position where said further valve port is open to allow oil to flow from the fourth port to said second port.

3. A thermal by-pass valve according to claim 2 including an override spring mounted on said shaft section and having one end thereof engaging said valve member so as to bias said valve member towards said primary valve seat.

4. A thermal by-pass valve according to claim 1 wherein said spacer member includes a sleeve section, an annular plate section extending around said sleeve section and a connection section joined to and extending from said plate section and connecting the spacer member to an end section of said actuator body, wherein said plate section is sized and arranged to act as a further valve device movable by said actuator between a closed position where flow between said fourth port and said second port is blocked and an open position where flow of oil from said fourth port of said second port can take place.

5. A thermal by-pass valve according to claim 4 wherein said connecting section is an internally threaded cylindrical section threaded on to an end section of said actuator.

6. A thermal by-pass valve according to claim 4 wherein said spacer member has guide members mounted around an outer periphery of said plate section and acting to guide movement of said spacer member between said closed and open positions.

7. A thermal by-pass valve according to claim 1 wherein a flow passage extends between said first port and said third port and is formed by said valve housing and said return spring extends across said flow passage whereby another end of the return spring engages an internal surface of the housing.

8. A thermal by-pass valve according to claim 1 wherein said valve housing includes a valve cap and a main body of the housing in which said valve cap is detachably mounted, said valve cap has a central recess formed in an inside surface thereof and aligned with a central longitudinal axis of said piston, and said piston extends into said recess when said piston is fully extended.

9. A thermal by-pass valve according to claim 8 wherein said spacer member includes a sleeve section forming said piston-receiving passage, an annular plate section extending circumferentially around said sleeve section and forming a valve portion, and a central connecting section for joining said spacer member to an end section of the actuator body, and wherein said plate section is movable by said actuator between a valve closed position where flow of oil between said fourth port and said second port is blocked and a valve open position where flow of oil from said fourth port to said second port can take place.

10. A thermal by-pass valve according to claim 9 wherein said valve chamber includes a relatively narrow first end section through which said return spring extends, a second end section adjacent said fourth port which has a larger diameter than said first end section, and a central section adjacent said second port and containing said actuator, said central section having a transverse width greater than the diameter of said second end section.

11. A thermal by-pass valve for a heat exchange circuit, comprising

a valve housing forming a valve chamber and a by-pass valve port surrounded by a primary valve seat, said valve port being located between first and second sections of the valve chamber, first and second fluid ports opening into the first section of the valve chamber and a third fluid port opening into said second section;

a thermally sensitive actuator mounted in said first section of the valve chamber and having an actuator body and an extendible piston located at one end of the actuator body, said actuator body being movable in said chamber in response to extension of said piston when said actuator body is heated to a predetermined temperature by surrounding heat exchange fluid during operation of said by-pass valve and in response to retraction of said piston;

a valve member operatively mounted on said actuator body so as to be movable by extension of said piston from a first position where said by-pass valve port is open to a second position where said by-pass valve port is closed by said valve member;

a return spring mounted in said second section of the valve chamber and having one spring end engaging an end section of the actuator body remote from said piston, said return spring biasing said actuator body away from the primary valve seat; and

a spacer projecting from and connected to said one end of the actuator body, said spacer forming a piston-receiving passage into which said piston extends during use of the by-pass valve, extension of said piston through said passage by a predetermined amount causing an end of said piston to engage said housing at or near one end of said chamber,

wherein said passage has a length and, during use of said by-pass valve, said spacer acts to maintain said one end of the actuator body at least said length of the passage away from said end of the chamber.

12. A thermal by-pass valve according to claim 11 wherein said spacer is a separate spacer member having a sleeve section which forms said passage, a central plate section extending around said sleeve section and forming a valve portion, and a connecting section that attaches said spacer member to said one end of the actuator body, and wherein said valve portion is movable by said actuator between a closed position where heat exchange fluid flow between said first and second fluid ports is at least substantially blocked and an open position where said heat exchange fluid flow between said first and second fluid ports can take place.

13. A thermal by-pass valve according to claim 12 wherein said connecting section is a cylindrical section attached to a head section of said actuator body, and wherein an override spring is mounted on and extends around a shaft section of the actuator body and has a first spring end engaging said valve member so as to bias said valve member towards said primary valve seat.

14. A thermal by-pass valve according to claim 12 wherein said connecting section comprises a plurality of resilient hook members detachably connected to an enlarged head section of said actuator body, said hook members being distributed around a central longitudinal axis of said sleeve section.

15. A thermal by-pass valve according to claim 12 wherein said valve housing includes a valve cap and a main body in which the valve cap is detachably mounted, said valve cap has a central recess forming in an inside surface thereof and aligned with a central longitudinal axis of said piston, and said piston extends into said recess when said piston is fully extended.

16. A thermal by-pass valve for a heat exchange circuit, comprising:

a valve housing forming a valve chamber and having at least three external ports for the flow of a heat exchange fluid into and out of said chamber and to and from a heat exchanger and an internal by-pass port surrounded by a primary valve seat and positioned between first and second sections of said valve chamber, two of said external ports opening into said first section of the chamber and at least one of said external ports opening into said second section;

a thermally sensitive actuator mechanism including an actuator body and a piston slidably mounted in said actuator body at one end thereof and adapted to move from a retracted position to an extended position when said actuator body is heated to a predetermined temperature by surrounding heat exchange fluid during operation of said by-pass valve, said actuator body being mounted in said first section of the chamber, said actuator mechanism further including a sleeve extending from and connected to said one end of the actuator body, said sleeve forming a piston-receiving passage into which said piston extends during use of the by-pass valve, whereby extension of said piston through said passage by a predetermined amount causes an end of said piston to engage said housing at or near one end of said chamber; and

a valve member operatively mounted on said actuator body so as to be movable by said extension of the piston from a first position where said by-pass port is open to a second position where said by-pass port is closed by said valve member,

wherein said piston-receiving passage has a length, and during use of said by-pass valve, said sleeve acts to maintain said one end of the actuator body at least said length of the passage away from said end of the chamber.

17. A thermal by-pass valve according to claim 16 wherein said actuator mechanism includes an annular valve portion extending around said sleeve and said piston and attached to said actuator body at said one end thereof, said valve portion extending radially outwardly relative to a central longitudinal axis of said piston and being movable by said actuator between a valve closed position where flow between said two external ports opening into the first section is blocked and a valve open position where flow of the heat exchange fluid between these two external ports can take place.

18. A thermal by-pass valve according to claim 17 wherein said actuator mechanism includes a return spring mounted in said second section of the valve chamber and having one end thereof engaging said actuator body at an end of the body remote from said piston so as to bias the actuator body away from said primary valve seat.

19. A combined spacer and valve device for use in a thermal by-pass valve for a heat exchange circuit, said valve having a thermally sensitive actuator with an actuator body and a piston slidably mounted in said actuator body and extendible from one end of said actuator body, said combined spacer and valve device comprising:

a sleeve section which forms a passage adapted to receive said piston;

an annular plate section connected to one end of the sleeve section, extending circumferentially around said sleeve section, and forming a valve portion of the device; and

a connecting section joined to said plate section on a side thereof opposite said sleeve section and capable of attending said device to said one end of the actuator body,

wherein, during use of the device in the by-pass valve attached to the actuator body, said valve portion is movable by said actuator between a closed position where flow of a heat exchange fluid between two ports of said valve is substantially blocked by said valve portion and an open position where said flow can take place.

20. A combined spacer and valve device according to claim 19 wherein said sleeve section has a length and is adapted to serve as a spacer to maintain said one end of the actuator body at least said length away from an adjacent end of a valve chamber formed by a valve housing of the by-pass valve.