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US 5,494,113 AGranted
Sprinklers with shape-memory alloy actuators
AssigneeCentral Sprinkler Corporation
InventorGeorge S. Polan
Life of this patent
Estimating the term…
Abstract
An automatic sprinkler includes a sprinkler body having a fluid passage outlet. A valve plug is maintained in sealing engagement with the fluid passage outlet by one or more control levers which react against the sprinkler body. Each control lever is held in position by a temperature-responsive actuator made from a generally C-shaped band of shape-memory alloy. The control band may be rigidly secured to one of the control levers. Upon an occurrence of a high-temperature condition, opposed ends of the control band spread apart in a common plane, releasing all control levers thereby permitting all control levers to pivot relative to the sprinkler body and release the valve plug from sealing engagement with the fluid passage outlet.
Claims31
A sprinkler, comprising:
- a sprinkler body including a fluid passage having an inlet and an outlet;
- a valve plug;
- and
- a temperature-responsive retaining mechanism supported by the sprinkler body and releasably retaining the valve plug in sealing engagement with the fluid passage outlet, the retaining mechanism including a temperature-responsive control band, a control lever, and a locating member, the control band having a generally C-shaped cross-section in a reference plane extending laterally through the control band and defining a pair of spaced-apart arms which extend laterally within the reference plane;
- wherein when the control band is in a low-temperature condition, the control lever and the locating member are supported by the control band such that a first portion of the control lever reacts, at least indirectly, against the sprinkler body, a second portion of the control lever urges the valve plug into sealing engagement with the fluid passage outlet, a third portion of the control lever reacts against the locating member through the control band, and the locating member reacts, at least indirectly, against the sprinkler body to retain the valve plug in sealing engagement with the fluid passage outlet;
- and
- when the control band undergoes a transition from the low-temperature condition to a high-temperature condition, a distance between the spaced-apart arms of the control band increases as measured in the reference plane sufficiently for the control band to release at least one of the supported control lever and locating member with a relative movement between the third portion of the control lever and the locating member and a movement of the second portion of the control lever moves away from the valve plug, thereby permitting release of the valve plug from sealing engagement with the fluid passage outlet.
4 more elements
The sprinkler as recited in 7, wherein a retainer member is secured to the stem, the retainer member passing through the predetermined lateral gap when the control band undergoes the transition from the low-temperature condition to the high-temperature condition.
A sprinkler, comprising:
- a sprinkler body including a fluid passage having an inlet and an outlet;
- a valve plug;
- and
- a temperature-responsive retaining mechanism supported by the sprinkler body releasably retaining the valve plug in sealing engagement with the fluid passage outlet, the retaining mechanism including a temperature-responsive control band and a control lever, the control band having a generally C-shaped cross-section in a reference plane extending laterally through the control band and defining a pair of spaced-apart arms which extend laterally within the reference plane;
- wherein when the control band is in a low-temperature condition, the control lever is supported by the control band relative to the sprinkler body such that a first portion of the control lever reacts, at least indirectly, against the sprinkler body, a second portion of the control lever urges the valve plug into sealing engagement with the fluid passage outlet, and a third portion of the control lever reacts against the sprinkler body through at least the control band, to retain the valve plug in sealing engagement with the fluid passage outlet;
- and
- when the control band undergoes a transition from the low-temperature condition to a high-temperature condition, a distance between the laterally extending arms of the control band increases as measured in the reference plane sufficiently to permit a relative movement between the third portion of the control lever and the sprinkler body and a movement of the second portion of the control lever away from the valve plug, thereby permitting release of the valve plug from sealing engagement with the fluid passage outlet.
4 more elements
A sprinkler, comprising:
- a sprinkler body including a fluid passage having an inlet and an outlet;
- a valve plug;
- and
- a temperature-responsive retaining mechanism supported by the sprinkler body releasably retaining the valve plug in sealing engagement with the fluid passage outlet, the retaining mechanism including a temperature-responsive control band, a control lever, and a locating member, the control band being rigidly secured to a first one of the control lever and the locating member;
- wherein when the control band is in a low-temperature condition, the control lever and the locating member are stably supported relative to the sprinkler body by the control band such that a first portion of the control lever reacts, at least indirectly, against the sprinkler body, a second portion of the control lever urges the valve plug into sealing engagement with the fluid passage outlet, a third portion of the control lever reacts against the locating member through the control band, and the locating member reacts, at least indirectly, against the sprinkler body to retain the valve plug in sealing engagement with the fluid passage outlet;
- and
- when the control band undergoes a transition from the low-temperature condition to a high-temperature condition, the control band changes in shape sufficiently to release a second one of the control lever and the locating member, with a relative movement between the third portion of the control lever and the locating member and a movement of the second portion of the control lever away from the valve plug, thereby permitting release of the valve plug from sealing engagement with the fluid passage outlet.
4 more elements
A sprinkler comprising:
- a sprinkler body including a fluid passage having an inlet and an outlet;
- a valve plug;
- and
- a temperature-responsive retaining mechanism including a temperature-responsive shape-memory alloy actuator changing shape with transition between different solid phases for releasing the valve plug from sealing engagement with the fluid passage outlet within 14 seconds when the shape-memory alloy actuator is exposed to a stream of hot air having a temperature of about 275.degree. F. moving at a rate of about 8.33 feet per second.
1 more element
A method of operating a sprinkler having a fluid passage inlet adapted to be connected to a source of fluid under pressure and a fluid passage outlet with a valve plug, the method comprising the steps of:
- providing a temperature-responsive retaining mechanism releasably retaining the valve plug in sealing engagement with the fluid passage outlet, the temperature-responsive retaining mechanism including a shape-memory alloy actuator changing shape with transition between different solid phases;
- automatically releasing the valve plug from sealing engagement with the fluid passage outlet within 14 seconds when the shape-memory alloy actuator is subjected to a stream of hot air having a temperature of about 275.degree. F. and moving at a rate of about 8.33 feet per second.
Dependencies are inferred from the claim text.