Shape memory circuit breakers

Abstract

A shape memory circuit breaker includes a shape memory substrate having first and second opposed substrate ends. The shape memory substrate is configured to transition from a strained conductive configuration to a fractured non-conductive configuration. An isolation housing is coupled with the shape memory substrate. The isolation housing includes first and second anchors coupled near the first and second substrate ends. A brace extends between the first and second anchors, and the brace statically positions the first and second anchors and the respective first and second substrate ends. The shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at or above a specified temperature range corresponding to a specified overload current range or voltage range, and the first substrate end fractures from the second substrate end at or above the specified temperature range resulting in an open circuit.

1 . A shape memory circuit breaker comprising:
 a shape memory substrate including first and second opposed substrate ends, the shape memory substrate is configured to transition from a strained conductive configuration to a fractured non-conductive configuration;   an isolation housing coupled with the shape memory substrate, the isolation housing includes:
 a first anchor coupled near the first substrate end, 
 a second anchor coupled near the second substrate end, and 
 a brace extending between the first and second anchors, the brace statically positions the first and second anchors and the respective first and second substrate ends; and 
   wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at or above a specified temperature range corresponding to a specified overload current range or voltage range, and the first substrate end fractures from the second substrate end at or above the specified temperature range resulting in an open circuit.   
     
     
         2 . The shape memory circuit breaker of  claim 1 , wherein the first and second anchors and the brace are electrically insulated from the shape memory substrate. 
     
     
         3 . The shape memory circuit breaker of  claim 2 , wherein the first and second anchors include insulated jaws engaged against the first and second substrate ends, respectively. 
     
     
         4 . The shape memory circuit breaker of  claim 1  comprising thermal insulation surrounding the shape memory substrate, the thermal insulation isolates the shape memory substrate from temperatures exterior to the thermal insulation. 
     
     
         5 . The shape memory circuit breaker of  claim 4 , wherein the brace includes the thermal insulation. 
     
     
         6 . The shape memory circuit breaker of  claim 1 , wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at the specified temperature wherein the specified temperature is less than a sublimation temperature of the shape memory substrate. 
     
     
         7 . The shape memory circuit breaker of  claim 1 , wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at the specified temperature wherein the specified temperature is less than a melting temperature of the shape memory substrate. 
     
     
         8 . The shape memory circuit breaker of  claim 1 , wherein in the fractured non-conductive configuration the first and second substrate ends include opposed fractured ends adjacent a fracture location, and in the fractured non-conductive configuration the opposed fractured ends are positioned remotely from each other. 
     
     
         9 . The shape memory circuit breaker of  claim 8 , wherein the opposed fracture ends are positioned a fracture length from each other in the fractured non-conductive configuration, and the fracture length is around 8 to 10 percent of a total length of the shape memory substrate between the first and second substrate ends. 
     
     
         10 . The shape memory circuit breaker of  claim 1  comprising an equipment housing and the equipment housing includes the brace and the first and second anchors. 
     
     
         11 . The shape memory circuit breaker of  claim 1 , wherein the shape memory substrate is a nickel-titanium alloy. 
     
     
         12 . The shape memory circuit breaker of  claim 1 , configured to operate as a fuse in a circuit by carrying current and is configured to transition from a closed circuit to the open circuit at the specified overload current range or voltage range, wherein the specified temperature range includes a specified temperature and the specified overload current or voltage range includes a specified overload current or voltage corresponding to the specified temperature. 
     
     
         13 . An equipment assembly comprising:
 one or more components configured to operate within a specified range of operational currents or voltages;   a shape memory circuit breaker electrically coupled with the one or more components to provide overload current or overload voltage protection for the equipment assembly, including:
 a shape memory substrate including first and second opposed substrate ends, 
 the shape memory substrate is configured to transition from a strained conductive configuration to a fractured non-conductive configuration at or above a specified range of transition temperatures, and 
 the specified range of transition temperatures correspond to overload currents or voltages greater than the specified range of operational currents or voltages of the equipment assembly; and 
   wherein the equipment assembly is operable with the shape memory substrate in the strained conductive configuration and inoperable with the shape memory substrate in the fractured non-conductive configuration.   
     
     
         14 . The equipment assembly of  claim 13 , wherein the shape memory circuit breaker is coupled in close proximity to the one or more components, and the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at or above the specified range of transition temperatures corresponding to an equipment assembly temperature above a specified operational temperature threshold. 
     
     
         15 . The equipment assembly of  claim 13  comprising first and second anchors engaged at the first and second substrate ends, respectively, and the first and second anchors are electrically insulated from the shape memory substrate. 
     
     
         16 . The equipment assembly of  claim 13  comprising a thermal insulator extending around the shape memory substrate, the thermal insulation isolates the shape memory substrate from temperatures exterior to the thermal insulation. 
     
     
         17 . The equipment assembly of  claim 13 , wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at the specified range of transition temperatures wherein the specified range of transition temperatures is less than a sublimation temperature of the shape memory substrate. 
     
     
         18 . The equipment assembly of  claim 13 , wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at the specified temperature wherein the specified temperature is less than a melting temperature of the shape memory substrate. 
     
     
         19 . The equipment assembly of  claim 13 , wherein the equipment assembly includes:
 a plurality of electrically operated components, and   a breaker housing, the breaker housing includes:
 a plurality of shape memory circuit breakers including the shape memory circuit breaker, and the plurality of shape memory circuit breakers are each configured to transition from the strained conductive configuration to the fractured non-conductive configuration, and 
 wherein each of the shape memory circuit breakers are each electrically coupled with separate electrically operated components of the plurality of electrically operated components, and each electrically operated component is operable with its respective shape memory substrate in the strained conductive configuration and inoperable with the shape memory substrate in the fractured non-conductive configuration. 
   
     
     
         20 . The equipment assembly of  claim 19 , wherein the breaker housing includes a plurality of anchors, and the plurality of shape memory substrates are separately coupled between the plurality of anchors. 
     
     
         21 . The equipment assembly of  claim 19 , wherein the shape memory circuit breaker includes:
 opposed anchors engaged with the first and second substrate ends, and   a brace extending between the opposed anchors, the brace statically positions the opposed anchors and the first and second substrate ends, and the shape memory circuit breaker is removably coupled with the breaker housing.   
     
     
         22 . The equipment assembly of  claim 21 , wherein the breaker housing includes electrical terminals interconnecting the first and second substrate ends with one of the electrically operated components. 
     
     
         23 . A method for making a shape memory circuit breaker comprising:
 straining a shape memory substrate into a strained configuration, the shape memory substrate including first and second substrate opposed ends, and the shape memory substrate is configured to transition from the strained configuration to the fractured configuration at or above a specified temperature range corresponding to a specified overload current range or voltage range, and the first substrate end fractures from the second substrate end at or above the specified temperature range;   securing the first and second substrate ends with the shape memory substrate in the strained configuration, the first substrate end is static relative to the second substrate end; and   thermally insulating the shape memory substrate from temperatures exterior to the shape memory substrate.   
     
     
         24 . The method of  claim 23 , wherein securing the first and second substrate ends includes securing the first and second substrate ends with electrically insulated first and second anchors, respectively. 
     
     
         25 . The method of  claim 23 , wherein securing the first and second substrate ends includes coupling a brace between the first and second anchors. 
     
     
         26 . The method of  claim 25 , wherein thermally insulating the shape memory substrate includes forming an isolation housing around the shape memory substrate, the isolation housing includes:
 the first and second anchors, and   the brace.   
     
     
         27 . The method of  claim 23 , wherein straining the shape memory substrate into the strained configuration includes straining the shape memory substrate in a martensitic phase. 
     
     
         28 . The method of  claim 23 , comprising cooling the shape memory substrate from an austenitic phase to the martensitic phase. 
     
     
         29 . A shape memory circuit breaker comprising:
 a shape memory substrate including first and second opposed substrate ends, the shape memory substrate is configured to transition from a strained conductive configuration to a fractured non-conductive configuration;   an isolation housing coupled with the shape memory substrate, the isolation housing includes:
 a first anchor coupled near the first substrate end, 
 a second anchor coupled near the second substrate end, and 
 a brace extending between the first and second anchors, the brace statically positions the first and second anchors and the respective first and second substrate ends; and 
   wherein the shape memory substrate is configured to transition from the strained conductive configuration to the fractured non-conductive configuration at or above a specified temperature range, wherein the specified temperature range is at or above a specified operational temperature threshold.   
     
     
         30 . The shape memory circuit breaker of  claim 29 , wherein the specified operational temperature threshold is for an equipment assembly the shape memory substrate is positioned near. 
     
     
         31 . The shape memory circuit breaker of  claim 29 , wherein in the fractured non-conductive configuration the first and second substrate ends include opposed fractured ends adjacent a fracture location, and in the fractured non-conductive configuration the opposed fractured ends are positioned remotely from each other. 
     
     
         32 . The shape memory circuit breaker of  claim 29 , wherein the first and second anchors and the brace are electrically insulated from the shape memory substrate.