# US 9,761,396 B2 · Magnet and actuator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,761,396 B2 - Document ID: US9761396B2 - Status: Granted - Kind: B2 - Application number: 15/115,701 - Filed: 2015-01-30 - Published: 2017-01-12 - Granted: 2017-09-12 - Earliest claimed: 2014-01-30 - Assignees: Ixtur Oy - Applicants: Ixtur Oy - Inventors: Reijo Nätti - Web page: https://patentgrep.com/patent/US9761396B2 ## CPC - H01H 36/0006: {Permanent magnet actuating reed switches (H01H35/147 takes precedence)} - G01D 5/12: using electric or magnetic means (G01D5/06 takes precedence) - H01F 7/0205: {Magnetic circuits with PM in general} - H01F 7/0226: {PM with variable field strength (H01F7/0284 takes precedence)} - H01F 7/0252: {PM holding devices (H01F7/021, H01F7/0215, H01F7/0226 take precedence)} - H01F 7/0257: {Lifting, pick-up magnetic objects} - H01F 7/0268: {Magnetic cylinders} - H01F 7/04: Means for releasing the attractive force - H01F 7/1615: {Armatures or stationary parts of magnetic circuit having permanent magnet} - H01F 7/132: {Armatures actuated by current pulse, e.g. bistable actuators} - 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) - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract The present invention provides a magnet, which comprises a body having a first and a second section, and a slide arranged to be movable relative to the body between a first and a second position. The slide comprises a permanent magnet, and a first and a second pole piece that are attached to opposite magnetic pole surfaces of the permanent magnet. The first section comprises a hole that opens into a first cavity of the body, the bottom of the first cavity being delimited at least partly by the second section. The slide is movably arranged in the hole so that the second pole piece is directed towards the bottom of the first cavity, wherein at the first position of the slide, magnetic flux generated by the permanent magnet is short-circuited by the first section, and at the second position of the slide, magnetic flux generated by the permanent magnet is directed through the first and the second section. ## Claims ### Claim 1 A magnet, comprising: a body having a first, a second, and a third section, and a slide arranged to be movable relative to the body between a first and a second position, the slide comprising a permanent magnet, and a first and a second pole piece attached to opposite magnetic pole surfaces of the permanent magnet; wherein the first section comprises a hole that opens into a first cavity of the body, bottom of the first cavity being delimited at least partly by the second section, in which hole the slide is movably arranged so that the second pole piece is directed towards the bottom of the first cavity, wherein at the first position of the slide, magnetic flux generated by the permanent magnet is short-circuited by the first section, and at the second position of the slide, magnetic flux generated by the permanent magnet is directed through the first and the second section, and wherein the third section is attached to the first section so that a second cavity is formed in the body, the second cavity being interconnected to the first cavity through the hole, and wherein the first and the second cavity contain a medium, and the body comprises a first conduit for conveying the medium into and out of the first cavity and a second conduit for conveying the medium into and out of the second cavity, a first end of the first conduit being arranged in communication with the first cavity and a first end of the second conduit being arranged in communication with the second cavity. ### Claim 2 (depends on 1) The magnet according to claim 1, wherein thickness of the permanent magnet is smaller than thickness of the first pole piece and thickness of the second pole piece. ### Claim 3 (depends on 1) The magnet according to claim 1, wherein thickness of the slide is larger than depth of the hole. ### Claim 4 (depends on 1) The magnet according to claim 1, wherein the first and the second section are attached together with a fourth section of the body, the fourth section being made of non-magnetic material. ### Claim 5 (depends on 4) The magnet according to claim 4, wherein the fourth section defines a wall of the first cavity. ### Claim 6 (depends on 1) The magnet according to claim 1, wherein the first and the second section form an integral part. ### Claim 7 (depends on 1) The magnet according to claim 1, wherein the magnet comprises a coil attached to the body, the coil being arranged to generate a magnetic force for moving the slide towards the first or the second position depending on the direction of electric current that is supplied to the coil. ### Claim 8 (depends on 7) The magnet according to claim 7, wherein the magnet comprises means for supplying electric current to the coil. ### Claim 9 (depends on 1) The magnet according to claim 1, wherein the first and the second cavity contain a medium, and the magnet comprises a third conduit for conveying the medium between the first and the second cavity, a first end of the third conduit being arranged in communication with the first cavity and a second end of the third conduit being arranged in communication with the second cavity. ### Claim 10 (depends on 1) The magnet according to claim 1, wherein the magnet comprises a pump coupled to a second end of the first and the second conduit. ### Claim 11 (depends on 1) The magnet according to claim 1, wherein the medium is gas or liquid. ### Claim 12 (depends on 1) The magnet according to claim 1, wherein the magnet comprises a sealing ring attached around the slide or attached to the wall of the hole. ### Claim 13 (depends on 12) The magnet according to claim 12, wherein the sealing ring is attached to a groove in the first pole piece. ### Claim 14 (depends on 1) The magnet according to claim 1, wherein the slide comprises a guiding rod extending from the second pole piece to a bore in the bottom of the first cavity. ### Claim 15 (depends on 1) The magnet according to claim 1, wherein the magnet comprises: a magnetic flux sensor configured to measure magnetic flux density in the first section, and means for determining the position of the slide based on the measured magnetic flux density. ### Claim 16 (depends on 15) The magnet according to claim 15, wherein the magnetic flux sensor is one of the following: a Hall sensor, an AMR magnetometer, a MEMS sensor or a reed relay.