# US 8,784,738 B2 · System for protecting circuitry in high-temperature environments > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,784,738 B2 - Document ID: US8784738B2 - Status: Granted - Kind: B2 - Application number: 13/873,942 - Filed: 2013-04-30 - Published: 2013-11-28 - Granted: 2014-07-22 - Earliest claimed: 2005-10-31 - Assignees: Codman Neuro Sciences Sarl - Applicants: Benito Valencia Avila; Alec Ginggen - Inventors: Benito Valencia Avila; Alec Ginggen - Web page: https://patentgrep.com/patent/US8784738B2 ## CPC - A61L 2/07: Steam - A61M 60/122: Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body - A61M 60/876: Implantable batteries - A61N 1/37: Monitoring; Protecting - H01H 37/72: Switches in which the opening movement and the closing movement of a contact are effected respectively by heating and cooling or vice versa - A61M 5/14276: {specially adapted for implantation} - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) ## Abstract An electrical device for performing a particular function includes a system circuit for performing the function, and a dedicated power supply for providing power to the circuit. Both the system circuit and the power supply are hermetically sealed within a housing. The device within the housing is intended to be sterilized using high temperature, reaching a sterilization temperature. According to the invention, the device includes a thermal switch which is electrically connected between the system circuit and the power supply. With the present invention, the electrical components of a device are automatically protected from thermal damage during sterilization. ## Claims ### Claim 1 An electrical device for performing a particular function, said device being of the type that requires sterilization using heat, said sterilization process reaching a sterilization temperature, said device comprising: a system circuit for selectively performing said particular function; a power supply for selectively providing sufficient power to said system circuit to allow said system circuit to perform said particular function; a housing for containing said system circuit, said housing being hermetically sealed; and a thermal-switch electrically connected between said power supply and said system circuit, said thermal switch being switchable between an open position wherein said system circuit is electrically isolated from said power supply and receives no power therefrom and a closed position wherein said system circuit is electrically connected to said power supply and receives power therefrom, said thermal switch switching from said closed position to said open position in response to the temperature within said housing rising to a predetermined switch-open temperature value, said thermal switch thereafter switching from said open position to said closed position in response to the temperature within said housing cooling to a switch-closed temperature value, said system circuit when said thermal-switch being in said open position being protected from thermal damage during sterilization, wherein said thermal switch is positioned outside said housing, and said device is one of the group consisting of an implantable infusion pump and an implantable pace maker. ### Claim 2 (depends on 1) The electrical device, according to claim 1, wherein said housing further contains said power supply. ### Claim 3 (depends on 1) The electrical device, according to claim 1, wherein said power supply is a battery. ### Claim 4 (depends on 1) The electrical device, according to claim 1, wherein said thermal switch includes a bi-metallic operator. ### Claim 5 (depends on 1) The electrical device, according to claim 1, wherein said thermal switch includes a controlling circuit. ### Claim 6 (depends on 1) The electrical device, according to claim 1, wherein said housing further includes said thermal switch. ### Claim 7 (depends on 1) The electrical device, according to claim 1, wherein said battery is positioned outside said housing. ### Claim 8 (depends on 1) The electrical device, according to claim 1, wherein said thermal switch includes a deformable member made from a shaped-memory-alloy, wherein said member deforms in response to a predetermined change in temperature, said deformation of said member controlling said electrical communication between said power supply and said system circuit. ### Claim 9 (depends on 1) The electrical device, according to claim 1, wherein said thermal switch includes a positive temperature coefficient resistor wherein the resistance of said resistor changes in response to changing temperature. ### Claim 10 An electrical device for performing a particular function, said device being of the type that requires sterilization using heat, said sterilization process reaching a sterilization temperature, said device comprising: a system circuit for selectively performing said particular function; a power supply for selectively providing sufficient power to said system circuit to allow said system circuit to perform said particular function; a housing for containing both said system circuit and said power supply, said housing being hermetically sealed; and a thermal-switch electrically connected between said power supply and said system circuit, said thermal switch being switchable between an open position wherein said system circuit is electrically isolated from said power supply and receives no power therefrom and a closed position wherein said system circuit is electrically connected to said power supply and receives power therefrom, said thermal switch switching from said closed position to said open position in response to the temperature within said housing rising to a predetermined switch-open temperature value, said thermal switch thereafter switching from said open position to said closed position in response to the temperature within said housing cooling to a switch-closed temperature value, said system circuit when said thermal-switch being in said open position being protected from thermal damage during sterilization, wherein said thermal switch is positioned outside said housing, and said device is one of the group consisting of an implantable infusion pump and an implantable pace maker. ### Claim 11 (depends on 10) The electrical device, according to claim 10, wherein said power supply is a battery.