# US 2012/0068794 A1 · Release mechanism for circuit interrupting device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2012/0068794 A1 - Document ID: US20120068794A1 - Status: Published application - Kind: A1 - Application number: 13/232,127 - Filed: 2011-09-14 - Published: 2012-03-22 - Earliest claimed: 2010-09-20 - Assignees: Secheron SA - Inventors: Christopher NAZERI - Web page: https://patentgrep.com/patent/US20120068794A1 ## CPC - H01H 71/321: {characterised by the magnetic circuit or active magnetic elements} - H01H 71/2436: {with a holding and a releasing magnet, the holding force being limited due to saturation of the holding magnet} - 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 A release mechanism for a circuit interrupting device includes a ferromagnetic main frame through which can flow a current and a ferromagnetic movable core designed to be translated in an opening of the main frame between a first position where the circuit interrupting device remains closed and a second position where the circuit interrupting device is opened. The release mechanism is designed to use the flux generated inside the main frame by the current flowing through it to displace the movable core between its first and second positions. The release mechanism further includes at least two permanent magnets mounted on the main frame on each side of the opening and relatively oriented so as to generate a unidirectional unique magnet flux inside the main frame and the movable core, the magnet flux creating a first force on the movable core that tends to maintain it in its first position. ## Claims ### Claim 1 Release mechanism (1) for a circuit interrupting device (2) comprising a ferromagnetic main frame (8) through which can flow a current (Ir; If) and a ferromagnetic movable core (13) designed to be translated in an opening (12) of the main frame (8) between a first position in which the circuit interrupting device (2) remains closed and a second position in which the circuit interrupting device (2) is opened; the said release mechanism designed to use the flux (FIf; FIr) generated inside the main frame (8) by the current (Ir; If) flowing through it to displace the movable core (13) between its first and second positions; characterised in that it further comprises at least two permanent magnets (14, 15) mounted on the main frame (8) on each side of the opening (12) and relatively oriented so as to generate a unidirectional unique magnet flux (FM) inside the main frame (8) and the movable core (13), the said magnet flux (FM) creating a first force on the movable core (13) that tends to maintain it in its first position; and in that the permanent magnets (14, 15), the movable core (13) and the main frame (8) are further conformed so that the movable core (13) is displaced from its first position into its second position when a first current (If) flowing through the main frame (8) and generating a first flux (FIf) inside the main frame (8) and the movable core (13) in the same direction as the magnetic flux (FM) exceeds a first limit value or when a second current (Ir) flowing through the main frame (8) and generating a second flux (FIr) inside the main frame (8) and the movable core (13) in the direction opposite to the magnetic flux (FM) exceeds a second limit value, the said second limit value being different than the first limit value. ### Claim 2 (depends on 1) Release mechanism (1) according to claim 1, characterised in that the movable core (13) presents a first and a second portion (13c, 13d) conformed so that a flux flowing through the first portion (13c) tends to displace the movable core (13) in its first position while a flux flowing through the second portion (13d) tends to displace the movable core (13) in its second position; and in that the permanent magnets (14, 15) and the said movable core (13) are further conformed so that the magnetic flux (FM) flows entirely through said first portion (13c). ### Claim 3 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the first and second portions (13c, 13d) of the movable core (13) present respectively first and second contact surfaces designed to cooperate with respectively with first and second contact surfaces on the main frame (8) to determine respectively the first and second position of said movable core (13) in the opening (12). ### Claim 4 (depends on 3) Release mechanism (1) according to claim 3, characterised in that the first contact surfaces of both the main frame (8) and the first portion (13c) of the movable core (13) are parallel and of the same area and are conformed to that a flux flowing inside the main frame (8) and passing through them creates a force on the first portion (13c) of the movable core (13) that tends to attract the said first contact surfaces against each other, thus moving the movable core (13) into its first position; and in that the second contact surfaces of both the main frame (8) and the second portion (13d) of the movable core (13) are parallel and of the same area, this area being bigger than the area of the first contact surfaces, and are conformed so that a flux flowing inside the main frame (8) and passing through them creates a force on the second portion (13d) of movable core that tends to attract the said second contact surfaces against each other, thus moving the movable core (13) into its second position. ### Claim 5 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the first and the second portion (13c, 13d) of the movable core are two cones of opposite direction. ### Claim 6 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the first and second portions (13c, 13d) together form a sphere. ### Claim 7 (depends on 1) Release mechanism (1) according to claim 1, characterised in that the first value is of a different order of magnitude than the second value. ### Claim 8 (depends on 1) Release mechanism (1) according to claim 1, characterised in that the first value is comprised between 2000 and 6000 amperes. ### Claim 9 (depends on 1) Release mechanism (1) according to claim 1, characterised in that the second value is greater than 90000 amperes. ### Claim 10 (depends on 1) Release mechanism (1) according to claim 1, characterised in that the main frame (8) is made of stacked ferromagnetic laminations insulated from each other by an insulating coating. ### Claim 11 (depends on 1) Release mechanism (1) according to claim 1, characterized in that the main frame (8) is made of silicon steel. ### Claim 12 (depends on 1) Release mechanism (1) according to claim 1, characterized in that it further comprises a spring (16) arranged to maintain the movable core (13) in its first position. ### Claim 13 (depends on 1) Circuit interrupting device (2) comprising a release mechanism according to claim 1. ### Claim 14 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the first value is of a different order of magnitude than the second value. ### Claim 15 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the first value is comprised between 2000 and 6000 amperes. ### Claim 16 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the second value is greater than 90000 amperes. ### Claim 17 (depends on 2) Release mechanism (1) according to claim 2, characterised in that the main frame (8) is made of stacked ferromagnetic laminations insulated from each other by an insulating coating. ### Claim 18 (depends on 2) Release mechanism (1) according to claim 2, characterized in that the main frame (8) is made of silicon steel. ### Claim 19 (depends on 2) Release mechanism (1) according to claim 2, characterized in that it further comprises a spring (16) arranged to maintain the movable core (13) in its first position. ### Claim 20 (depends on 2) Circuit interrupting device (2) comprising a release mechanism according to claim 2.