WO2018227289A1

WO2018227289A1 - Release valve with fail-safe

Info

Publication number: WO2018227289A1
Application number: PCT/CA2018/050710
Authority: WO
Inventors: Erick Girouard; Amir AHMADZADEGAN
Original assignee: Emcara Gas Development Inc.
Priority date: 2017-06-13
Filing date: 2018-06-13
Publication date: 2018-12-20
Also published as: CA3067266A1

Abstract

There is provided a valve comprising a body including an inlet, an outlet, and a fluid passage extending from the inlet to the outlet, a closure member displaceable, relative to the fluid passage, from a closed position to an open position for effecting fluid communication between the inlet and the outlet, a retainer for retaining the closure member in the closed position, and an actuator including a stimulus responder for receiving a predetermined stimulus and effecting release of the closure member from retention by the retainer in response to the receiving of a predetermined stimulus.

Description

RELEASE VALVE WITH FAIL-SAFE CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims benefit of and priority to U.S. Provisional Patent

Application No. 62/518,672 filed June 13, 2017, the contents of which are incorporated herein by reference.

FIELD

[0002] The present disclosure relates to a valve for venting fluid from a tank, and, in particular, relates to a temperature activated valve with a fail-safe mode for venting fluid from a tank.

BACKGROUND

[0003] Current pressure relief valve technology which utilize temperature activated triggers, including the use of shape memory alloys, are devices which rely on a pressure differential between an inlet in fluid communication with a pressurized tank and an outlet that is at atmospheric pressure to actuate the release mechanism. Thermally actuated valves include those described and illustrated in Applicant's U.S. Patent Nos. 9,121 ,521 and 9,097,358, herein incorporated by reference in their entireties. Current thermally actuated valves may use shape memory alloy wires as the temperature trigger. However, if the wire fails, such as due to an accidental severing, the valve may be rendered inoperational. In such cases, a pressurized tank would not be able to vent its contents in response to an increase in temperature in the pressurized tank.

SUMMARY

[0004] In one aspect, there is provided a valve comprising a body including an inlet, an outlet, and a fluid passage extending from the inlet to the outlet; a closure member displaceable, relative to the fluid passage, from a closed position to an open position for effecting fluid communication between the inlet and the outlet; a retainer for retaining the closure member in the closed position; and an actuator including a stimulus responder for receiving a predetermined stimulus and effecting release of the closure member from retention by the retainer in response to the receiving of a predetermined stimulus; wherein the closure member, the retainer, and the actuator are co-operatively configured such that the closure member is retained by the retainer in the closed position, while (i) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, and (ii) there is an absence of receiving of a predetermined stimulus by the stimulus responder; while (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, in response to receiving of a predetermined stimulus by the stimulus responder, the closure member becomes released from the retention by the retainer; and while (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, in response to a defeating of the stimulus communicating relationship between the retainer and the stimulus responder, the closure member becomes released from the retention by the retainer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Fig. 1 is a cross-view of a valve in a non-venting mode according to an embodiment of the invention.

[0006] Fig. 2 is a cross-view of a valve in a venting mode according to the embodiment of Fig 1.

[0007] Fig. 3 is a cross-view of a valve in a fail-safe mode according to the embodiment of Fig 1.

[0008] Fig. 4 is a schematic view of a valve according to an embodiment connected to a pressurized tank.

DETAILED DESCRIPTION

[0009] Referring to Figures 1 to 3, there is provided an embodiment of a valve apparatus 200 for attachment, either directly or indirectly, to an opening (such as a port) of a container such as, for example, a vessel or tank containing liquids or gases held under pressure such as a tank 100, as depicted in Figure 4. [0010] The valve apparatus 200 includes a body 201 . The body 201 defines an inlet port 202, an outlet port 204, a fluid passage 206, and a closure member receiving passage 209. The inlet port 202 is configured for fluid coupling to a tank 100 for receiving gaseous material from the tank 100. The outlet port 204 is configured for venting the received gaseous material to the immediate environment (for example, the atmosphere). For example, the material of the body 20 is metallic. Suitable metallic materials include brass, aluminum, or stainless steel.

[001 1] The valve apparatus 200 further includes a closure member 208 for closing fluid communication between the inlet port 202 and the outlet port 204. The closure member 208 is moveable between a closed position and an open position within the closure member receiving passage 209. The discharge fluid passage 206 extends from the inlet port 202 to the outlet port 204 for effecting fluid communication between the inlet and outlet ports 202, 204, when the closure member 208 is disposed in the open position. In the closed position, fluid communication between the inlet port 202 and the outlet port 204 is sealed or substantially sealed. In the open position, fluid communication is effected between the inlet port 202 and the outlet port 204.

[0012] In some embodiments, for example, the closure member 208 includes a closure member body 208A which carries an o-ring 208B, for effecting sealing engagement of the closure member 208 to the body 201 while the closure member 208 is disposed in the closed position such that fluid is prevented from flowing from the inlet port 202 to the outlet port 204. The closure member body 208A is made from one or more of a variety of materials including metal. For example, a suitable metal is steel. The o-ring 208B may be made from elastomeric material.

[0013] The valve apparatus 200 further includes a trigger mechanism. In some embodiments, the trigger mechanism is an actuator 210. The actuator 210 is provided for effecting a change in condition to the closure member 208, in response to receiving of a predetermined stimulus, such that the closure member 208 becomes displaceable from the closed position to the open position. The actuator 210 is configured to assume a change in its condition, from a non-actuating position to an actuating position, in response to receiving of a predetermined stimulus. In some embodiments, for example, the predetermined stimulus includes heat energy, such that the valve apparatus 200 is a thermally actuated valve. Exemplary thermally actuated valves are described and illustrated in U.S. Patent Nos. 9,121 ,521 and 9,097,358, which are hereby incorporated by reference.

[0014] When the valve apparatus 200 is a thermally actuated valve, in some of these embodiments, for example, the actuator 210 includes a temperature responsive portion 21 OA, and the predetermined stimulus is heat energy that is sufficient to increase the temperature of the temperature responsive portion 21 OA to above a predetermined minimum temperature. In some embodiments, for example, the receiving of heat energy by the actuator 210 effects a change in shape of the heated portion of the temperature responsive portion 21 OA such that a change in dimension of the temperature-responsive portion 21 OA is effected. In some of these embodiments, for example, the temperature responsive portion 21 OA includes a longitudinal axis, and the change in shape includes a reduction in length of the temperature responsive portion 21 OA along its longitudinal axis. In this respect, in some embodiments, for example, the temperature responsive portion 21 OA includes shape memory alloy material.

[0015] A fire or other heat source which can effect displacement of the actuator 210 can also effect heating of the tank 100 to which the valve apparatus 200 is attached. In such cases, in some embodiments, for example, the displacement of the actuator 208 is effected by the heat before the heating of the tank 100 effects the failure of the tank 100 such that gaseous material within the tank 100 is vented remotely from the fire. "Failure" of the tank 100 occurs when the integrity of the tank 100 is compromised, such as by, for example, rupturing, breaking or melting. By enabling such venting of the gaseous material within the tank 100 before the failure of the tank 100, the risk of explosion, effected by heating of the gaseous material stored within the tank 100, is mitigated.

[0016] Additionally, the apparatus 200 further includes a retainer 210B. The retainer

210B is retaining the closure member 208 in the closed position.

[0017] The closure member 208, the retainer 210B, and the actuator 210 are cooperatively configured such that the closure member 208 is retained by the retainer 210B in the closed position, while: (i) the retainer 210B and the actuator 210 are disposed in a stimulus communicating relationship, and (ii) there is an absence of receiving of a predetermined stimulus by the actuator 210. In some embodiments, for example, the stimulus communicating relationship includes coupling of the retainer 210B and the actuator 210. In some embodiments, for example, the absence of receiving of a predetermined stimulus by the actuator 210 includes circumstances where the temperature responsive portion 21 OA is disposed below the predetermined minimum temperature.

[0018] The closure member 208, the retainer 21 OB, and the actuator 210 are cooperatively configured such that while: (i) the retainer 210B is retaining the closure member 208 in the closed position, and (ii) the retainer 210B and the actuator 210 are disposed in a stimulus communicating relationship, in response to receiving of a predetermined stimulus by the actuator 210, the closure member 208 becomes released from the retention by the retainer 210B. In some of these embodiments, for example, the release from the retention is effected in response to the temperature responsive portion 21 OA becoming disposed at or above the predetermined minimum temperature.

[0019] In this respect, in some embodiments, for example, while the actuator 210 is disposed in the actuated position, and the closure member 208 is released from retention by the retainer 210B, the closure member 208 is displaceable from the closed position to the open position in response to a sufficient pressure differential being provided between the inlet 202 and the outlet 204 (i.e. while the actuator 210 is disposed in the actuated position, the closure member 208 is displaced from the closed position to the open position when the pressure differential between the inlet 202 and the outlet 204 exceeds a predetermined minimum pressure differential). In some of these embodiments, for example, the inlet 202 is disposed in fluid communication with the tank 100, and is, thereby, exposed to fluid pressure within the tank 100, and the outlet 204 is disposed in fluid communication with the atmosphere and is, thereby, exposed to atmospheric pressure, such that, so long as the fluid pressure within the tank 100 exceeds atmospheric pressure by a predetermined minimum pressure differential, and so long as the actuator 210 is disposed in the actuated position, the closure member 208 will become displaced from the closed position to the open position.

[0020] In some embodiments, for example, the actuator 210 includes a movable portion

210C. The movable portion 210C is coupled to the retainer 210B, such that the release of the closure member 208 from the retention in the closed position by the retainer 210B is effected by movement of the movable portion 210C. The body 201 includes an actuator-receiving passage 21 1 for receiving the movable portion 201 C during movement of the movable portion 210C. In some embodiments, for example, in response to the receiving of heat energy by the actuator 210, the heated temperature responsive portion 21 OA effects exertion of a tensile force, thereby effecting the movement of the moveable portion 210C such that the actuator 210 becomes disposed in the actuated position. In some embodiments (not shown), for example, the moveable portion 210C includes the retainer 21 OB, such that the retainer 21 OB translates with the moveable portion 210C.

[0021] In some embodiments, for example, the moveable portion 210C is separate from the retainer 21 OB. In this respect, in some embodiments, for example, the actuator 210 includes a retainer actuator 21 OX that is separate from the retainer 210B. In some embodiments, for example, the retainer actuator 21 OX translates with the movable portion 210C. In some embodiments, for example, the retainer actuator 21 OX is displaceable, relative to the retainer 210B, from a retaining position to a released position, in response to the receiving of heat energy and upon the disposition of the temperature responsive portion 210 at a temperature that is at or above the predetermined minimum temperature. While disposed in the retaining position (see Fig 1 ), the retainer actuator 21 OX is retaining the retainer 210B in a position relative to the closure member 208 such that the retainer 210B retains the closure member 208 in the closed position. While the retainer actuator 21 OX is disposed in the released position (see Fig 2), the retainer 210B is released from retention by the retainer actuator 21 OX such that the retainer 210B is displaceable relative to the closure member 208 for effecting the release of the retention of the closure member 208 in the closed position. In this respect, while the retainer actuator 21 OX is disposed in the released position, the retention of the closure member 208, in the closed position, by the retainer 210B, is defeatable.

[0022] In those embodiments where the retainer actuator 21 OX is separate from the retainer 210B, in some of these embodiments, for example, and referring to Figures 1 and 2, the retainer 210B includes a free ball 210BB. In some embodiments, for example, the material of construction of the ball 210BB is steel.

[0023] In some embodiments, for example, the retention of the closure member 208 in the closed position by the ball 210BB is effected by interference to displacement of the closure member, from the closed position to the open position, by the ball 210BB. In some embodiments, for example, the interference is effected by disposition of the ball 210BB within a recess 208C (such as, for example, a cut-out) of the closure member 208. Co-operatively, in effecting this interference, the retainer actuator 21 OX and a ball-retaining surface 201 A of the body 201 prevents, or substantially prevents, release of the ball 210BB from its disposition within the recess, while the retainer actuator 21 OX is disposed in the retaining position.

[0024] In this respect, the ball-retaining surface 201A, prevents, or substantially prevents, displacement of the ball 210BB, relative to the body 201 , that is being urged by a pressure differential established between the inlet 202 and the outlet 202, that is urging the displacement of the closure member 208 from the closed position to the open position. The force (arising from a pressure differential, such as a pressure differential that exceeds the predetermined minimum pressure differential) that is urging the displacement of the closure member 208 from the closed position to the open position, in combination with the above- described opposition provided by the ball-retaining surface 201A, results in a net force that urges release of the ball 210BB from the recess 208C, and, while disposed in the retaining position, the retainer actuator 21 OX opposes such force and retains the ball 210BB within the recess 208C (in the illustrated embodiment, the retainer actuator 21 OX prevents, or substantially prevents, movement of the ball 210BB along an axis that is orthogonal to the axis along which the closure member 208 is movable to the open position). When the retainer actuator 21 OX becomes disposed in the released position, such opposition is absent, permitting the pressure differential to liberate the ball 210BB from the recess, and thereby releasing the closure member 208 from retention by the ball 210BB and enabling its displacement to the open position, in response to application of a pressure differential between the inlet 202 and the outlet 204 that exceeds the minimum predetermined pressure differential, as explained above.

[0025] While the retainer actuator 21 OX is disposed in the retaining position, and gaseous material is disposed within the tank 100 such that a pressure differential, exceeding the predetermined minimum pressure differential, is urging displacement of the closure member 208 to the open position, force is transmitted by the closure member 208 to the ball 210BB, and the ball 210BB transmits most of the force being applied to the closure member 208 onto the body 201 , while transmitting a smaller force onto the actuator 210. By having the retainer 210B separated from the temperature responsive portion 21 OA, such as is the case with the above- described embodiments with the ball 210BB, less frictional resistance is impartable to the moveable portion 210C when it is being displaced by tensile forces resulting from the receiving of heat by the temperature responsive portion 21 OA, compared to when the retainer 210B is integral with the moveable portion 210C. This allows for greater flexibility in the choice of materials for the temperature responsive portion 21 OA, which may, for example, be a wire (for example, comprising a shape memory alloy).

[0026] In some embodiments, for example, the actuator 210 further includes a retainable portion configured for retention of the actuator 210 relative to a source of pressurized fluid pressurized fluid material. In some embodiments the retainable portion includes a fixedly couplable portion 210D. The fixedly couplable portion 210D is configured for being fixed, or substantially fixed, relative to the body 201 such that, while the fixedly couplable portion 210D is fixed, or substantially fixed, relative to the body 201 , in response to the receiving of sufficient heat energy by the actuator 210, the moveable portion 210C is displaced relative to the fixedly couplable portion 210D such that the spacing between the moveable portion 210C and the fixedly couplable portion 210D is reduced.

[0027] In some embodiments, for example, the fixing, or substantial fixing, of the spatial disposition of the fixedly couplable portion 210D, relative to the body 201 , is effected by connection between the body 201 and a connector 224. For example, the connector 224 is made from metallic material, and suitable metallic materials includes copper, stainless steel, brass or aluminum, or a combination of said materials. The connector 224 is stiffer than the moveable portion 210C of the actuator 210. In some embodiments, for example, the connector 224 is of a tubular form, extending from the body 201 , and attached to the actuator 210 with a retaining assembly 226. The retaining assembly 226 includes a washer 226A and a crimp 226B. The washer 226A is disposed in an interference relationship with the connector 224 such that the washer 226A is fixed, or substantially fixed, relative to the connector 224. The actuator 226 extends through a hole within the washer 226A and its displacement through the hole is restricted by the crimp 226B which is clamped onto an end 210E of the actuator 210. While the crimp 226B is clamped onto the end 210E of the actuator 210, the hole of the washer 226A and the crimp 226B are co-operatively configured such that passage of the crimp 226B through the hole, in the direction of the retainer 210B of the actuator 210, is restricted, with effect that passage of the end 210E of the actuator 210 towards the retainer 210B is restricted and thereby effecting fixing, or substantial fixing, of the end 210E of actuator 210 relative to the body 201 .

[0028] In some embodiments, for example, the retaining assembly 226 is closed or covered by a cap 229 which is connected to the connector 224. Fastening of the connector 224 to the retaining assembly 226 is then effected with a nut 235, which is threaded to the cap 229, and which forces a ferrule 234 to pinch the connector 224. In this respect, during assembly, the nut 235 and the ferrule 234 are slid over the end of the connector 224 which is desired to be fastened to the cap 229. The connector 224 is then pushed into an aperture provided within the cap 229. The nut 235 is then tightened until the ferrule 234 squeezes the connector 224. For example, the cap 229 is made using metallic material, such as brass or stainless steel. In some embodiments, for example, the cap 229 functions to cover the assembly of the retaining assembly 226 to, amongst other things, prevent, or mitigate, material ingress or physical damage.

[0029] In some embodiments, for example, the fixing, or substantial fixing, of the spatial disposition of the fixedly couplable portion 210D, relative to the body 201 , is effected by an indirect connection to the body 201. In this respect, in some embodiments, for example, the connector 224 effects attachment of the fixedly couplable portion 210D to the tank 100 to which the body 201 is connected. In some of these embodiments, for example, the connector 224 is a strap, band or other fastener.

[0030] It is understood that a portion of the actuator 210 is not required to be spatially fixed, or substantially fixed, relative to the body 201 , in order for the actuation of the closure member 208 to be effected in response to receiving of heat by the temperature responsive portion 21 OA. However, by effecting the fixing, or substantial fixing, of the spatial disposition of the fixedly couplable portion 210D, relative to the body 201 , displacement of the moveable portion 210C, effected in response to a change in dimension of the temperature responsive portion 210 (that is effected by the receiving of sufficient heat energy by the actuator 210), is more pronounced (such as, for example, a greater displacement of the moveable portion 210C is realized) than the case where a portion of the actuator 210 is not spatially fixed, or substantially fixed, relative to the body 201 .

[0031] In some embodiments, for example, the actuator 210 is disposed within a sleeve

240 that is disposed within the connector 224. The sleeve 240 functions to reduce friction between the actuator 210 and the connector 224, during movement of the actuator 210 through the connector 224, in parallel with the displacement of the retainer 210B. In some embodiments, for example, the sleeve 240 is disposed in interference fit relationship with the connector 224. In some embodiments, for example, the sleeve 240 is made from a plastic, such as polytetrafluoroethylene. In some embodiments, for example, the sleeve 240 is made from TEFLON™.

[0032] In some embodiments, for example, the temperature responsive portion 21 OA is disposed at least between the fixedly couplable portion 210D and the moveable portion 210C. retainer 21 OB. In some of these embodiments, for example, the moveable portion 210C includes at least a portion of the temperature responsive portion 210A.

[0033] In those embodiments where the material of the temperature responsive portion

21 OA is a shape memory alloy, in some of these embodiments, for example, the temperature, at which the temperature responsive portion 21 OA assumes a change in shape, is modified by a shape changing temperature modifier 212. In some embodiments, the shape changing temperature modifier 212 includes a biasing member 216. The biasing member 216, the temperature responsive portion 21 OA, and the fixedly couplable portion 210D are co-operatively configured such that, while the fixedly couplable portion 210D is fixed relative to the body 201 , the biasing member 216 exerts a tensile force on the temperature responsive portion 21 OA, thereby effecting a change to the shape changing characteristics of the temperature responsive portion 21 OA.

[0034] In some embodiments, for example, the actuator 210 includes a housing 218, such that the movable portion 210C includes a housing 218 that is coupled to the temperature responsive portion 21 OA. The temperature responsive portion 21 OA is pinched between a pin 214 and the housing 218, such that the temperature responsive portion 210A is coupled to the housing 218. The housing 218 contains the biasing member 216 and is disposed in force transmission communication with the biasing member 216 such that the biasing member 216 is exerting a tensile force to the temperature responsive portion 21 OA. For example, the biasing member 216 is a resilient member, such as a spring. For example, the spring is a coil spring made from steel. The biasing member 216 is coupled to the body 201 with a retainer 220. The retainer 220 is fastened to the body 201. For example, the retainer 220 is in the form of a nut which threads into complementary threads provided on an external surface of the body 201 , thereby retaining the biasing member 216 relative to the body 201. For example, the material of the retainer 220 is metallic. Suitable metallic materials include brass, aluminum, or stainless steel. For example, the material of the pin 214 is a metal, such as steel. In some embodiments, for example, the attachment of the connector 224 to the body 201 is effected by connection of the connector to the retainer 220.

[0035] The biasing member 216, the housing 218, and the fixedly couplable portion

210D are co-operatively configured such that, while the fixedly couplable portion 210D is fixed relative to the body 201 , the biasing member 216 presses against the housing 218, urging the housing 218 away from the fixedly couplable portion 210D. The retainer 220 includes a passage 222 which receives the temperature responsive portion 21 OA so as to facilitate the coupling of the temperature responsive portion 21 OA to the shape changing temperature modifier 212 and to facilitate movement of the moveable portion 210C (which, in this case, includes the temperature responsive portion 210C). In this respect, while the fixedly couplable portion 210D is fixedly coupled to the tank 100, by pressing against the housing 218, and urging the housing 218 away from the fixedly couplable portion 210D, the biasing member 216 effects application of a tensile force to the temperature responsive portion 21 OA such that the shape changing temperature characteristics of the temperature responsive portion 21 OA are modified.

[0036] The release of the closure member 208 from retention by the retainer 210B is effectible so long as the retainer 210B and the temperature responsive portion 21 OA are cooperatively disposed (disposed in a "stimulus communicating relationship") such that the retainer 210B is responsive to the disposition of the temperature responsive portion 21 OA at a temperature that exceeds the predetermined minimum temperature. When such co-operative disposition no longer exists (the stimulus communicating relationship is defeated), releasing of the closure member 208, based on this relationship between the retainer 210B and the temperature responsive portion 21 OA, is no longer possible. To mitigate versus the defeating of the stimulus communicating relationship, the apparatus is configured such that the retention of the closure member 208, by the retainer 210B, in response to the defeating of the stimulus communicating relationship.

[0037] In this respect, the closure member 208, the retainer 210B, and the temperature responsive portion 210B are further co-operatively configured such that while: (i) the retainer 210B is retaining the closure member 208 in the closed position, and (ii) the retainer 210B and the temperature responsive portion 21 OA are disposed in a stimulus communicating relationship, in response to a defeating of the stimulus communicating relationship between the retainer 21 OB and the temperature responsive portion 21 OA, the closure member 208 becomes released from the retention by the retainer 21 OB.

[0038] In those embodiments where the actuator 210 includes a wire, in some of these embodiments, the defeating of the stimulus communicating relationship is effected by severing of the wire.

[0039] In some embodiments, for example, the biasing member 216 is responsible for urging the displacement of the retainer actuator 21 OX, relative to the ball 210BB, from the retaining position to a second released position, with effect that the retention of the ball 210BB (i.e. the retainer) relative to the closure member 208 is released, thereby enabling its release from the recess 208C and, thereby, the release of the closure member 208 from retention by the ball 210BB. In this respect, the actuator receiving passage 21 1 includes sufficient space for receiving the retainer actuator 21 OX when the retainer actuator 21 OX is displaced to a second released position.

[0040] In the above description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present disclosure. Although certain dimensions and materials are described for implementing the disclosed example embodiments, other suitable dimensions and/or materials may be used within the scope of this disclosure. All such modifications and variations, including all suitable current and future changes in technology, are believed to be within the sphere and scope of the present disclosure. All references mentioned are hereby incorporated by reference in their entirety.

Claims

WHAT IS CLAIMED IS:

1 . A valve comprising:

a body including an inlet, an outlet, and a fluid passage extending from the inlet to the outlet;

a closure member displaceable, relative to the fluid passage, from a closed position to an open position for effecting fluid communication between the inlet and the outlet;

a retainer for retaining the closure member in the closed position; and

an actuator including a stimulus responder for receiving a predetermined stimulus and effecting release of the closure member from retention by the retainer in response to the receiving of a predetermined stimulus;

wherein the closure member, the retainer, and the actuator are co-operatively configured such that:

the closure member is retained by the retainer in the closed position, while: (i) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, and (ii) there is an absence of receiving of a predetermined stimulus by the stimulus responder; while: (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, in response to receiving of a predetermined stimulus by the stimulus responder, the closure member becomes released from the retention by the retainer; and

while: (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, in response to a defeating of the stimulus communicating relationship between the retainer and the stimulus responder, the closure member becomes released from the retention by the retainer.

2. The valve as claimed in claim 1 ;

further comprising:

a biasing member;

wherein the closure member, the retainer, the stimulus responder, and the biasing member are co-operatively configured such that the releasing of the closure member from the retention by the retainer, in response to the defeating of the stimulus communicating relationship between the retainer and the stimulus responder, is effected by the biasing member.

3. The valve as claimed in claim 2;

wherein the biasing member and the stimulus responder portion are co-operatively configured such that the biasing member opposes the releasing of the closure member, from the retention by the retainer, that is effected in response to receiving of a predetermined stimulus by the stimulus responder.

4. The valve as claimed in claim 1 ;

wherein the predetermined stimulus is heat energy that is sufficient to increase the temperature of the stimulus responder to above a predetermined minimum temperature.

5. The valve as claimed in claim 4;

wherein the stimulus responder includes shape memory alloy material.

6. The valve as claimed in claim 4 or 5;

wherein the closure member, the retainer, and the stimulus responder are also cooperatively configured such that, while: (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, the receiving of heat energy, by the actuator, that is sufficient to increase the temperature of the stimulus responder to above a predetermined minimum temperature, effects a change in a dimension of the stimulus responder, such that the release of the closure member from the retention by the retainer is mediated by the change in a dimension of the stimulus responder.

7. The valve as claimed in claim 6;

further comprising:

a biasing member;

8. The valve as claimed in claim 7;

wherein the biasing member, the closure member, and the stimulus responder are cooperatively configured such that the biasing member opposes the releasing of the closure member, from the retention by the retainer, that is being urged by the change in a dimension of the stimulus responsive portion.

9. The valve as claimed in claim 7 or 8;

wherein:

the actuator further includes a retainer actuator;

the body, the retainer, the stimulus responder, the biasing member, and the closure member are co-operatively configured such that:

the retainer is retained by the retainer actuator while: (i) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, and (ii) there is an absence of receiving of a predetermined stimulus by the stimulus responder, with effect that the closure member is retained by the retainer in the closed position; and while: (i) the retainer is retaining the closure member in the closed position, and (ii) the retainer and the stimulus responder are disposed in a stimulus communicating relationship, in response to the change in dimension of the stimulus responder effected by the increase in temperature of the stimulus responder to above the predetermined minimum temperature, the retainer actuator is displaced relative to the retainer, with effect that the retainer becomes released from retention by the retainer actuator, and with effect that the release of the closure member, from the retention by the retainer, is effectible in response to communication of fluid pressure from the inlet.

10. The apparatus of any one of claims 1 to 9,

wherein the actuator includes a wire and the wire includes the stimulus responder.