# US 12,184,274 B2 · Miniaturized, inductive proximity sensor and method for detecting a sensing body > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,184,274 B2 - Document ID: US12184274B2 - Status: Granted - Kind: B2 - Application number: 17/929,155 - Filed: 2022-09-01 - Published: 2023-03-09 - Granted: 2024-12-31 - Earliest claimed: 2021-09-03 - Assignees: Turck Holding GmbH - Applicants: TURCK Holding GmbH - Inventors: Michael Faber - Web page: https://patentgrep.com/patent/US12184274B2 ## CPC - H03K 17/9505: {Constructional details} - H03K 17/952: {using inductive coils} - G01V 3/104: {using several coupled or uncoupled coils (G01V3/101 takes precedence)} - G01V 3/107: {using compensating coil or loop arrangements} - H01F 27/2809: {on stacked layers} - H03K 17/9542: {forming part of an oscillator} - H03K 2017/9527: {Details of coils in the emitter or receiver; Magnetic detector comprising emitting and receiving coils} - H05K 1/144: {Stacked arrangements of planar printed circuit boards} - H05K 1/165: {incorporating printed inductors} - H05K 2201/10098: Components for radio transmission, e.g. radio frequency identification [RFID] tag, printed or non-printed antennas - H05K 2201/10151: Sensor - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract In an embodiment, an inductive proximity sensor includes two receiving coils and one transmitting coil arranged between the two receiving coils. The receiving coils and transmitting coil are each formed from a group of at least two individual coils on carrier boards, which are arranged parallel to one another. The carrier boards have a diameter which is smaller than or equal to 10 mm, and a winding of the receiving coils or the transmitting coil has a cross-sectional geometry in which a ratio of a base width to a height lies in the range from 0.2 to 0.3. An embodiment of a method for detecting an object using an inductive proximity sensor includes generating an alternating field using a transmitting coil of the proximity sensor and sensing, using two receiving coils of the inductive proximity sensor, a change in the alternating field caused by proximity of the object. ## Claims ### Claim 1 An inductive proximity sensor for detecting an object, the proximity sensor comprising: two receiving coils; a top board not including coils and configured to act as an interface with terminal pads for connection to circuitry including a generator or oscillator; and one transmitting coil arranged between the two receiving coils, wherein the receiving coils and transmitting coil are each formed from a group of at least two individual coils on carrier boards, which are arranged parallel to one another and axially offset as a stack along a common sensor axis, the carrier boards have a diameter which is smaller than or equal to 10 mm, and a winding of the receiving coil or the transmitting coil has a cross-sectional geometry in which a ratio of a base width to a height lies in a range of from 0.2 to 0.3, ideally between 0.23 and 0.27. ### Claim 2 (depends on 1) The sensor of claim 1, wherein the height does not exceed 0.05 mm. ### Claim 3 (depends on 1) The sensor of claim 1, wherein a number of turns of at least one individual coil of the receiving coils is equal to or greater than 3. ### Claim 4 (depends on 1) The sensor of claim 1, wherein a number of turns of at least one individual coil of the transmitting coil is equal to or greater than 3. ### Claim 5 (depends on 1) The sensor of claim 1, wherein a central individual coil of the transmitting coil lies in a symmetry plane of the stack of individual coils. ### Claim 6 (depends on 1) The sensor of claim 1, wherein the transmitting coil has a number n of individual coils and the two receiving coils together have a number of at least n+1 individual coils. ### Claim 7 (depends on 1) The sensor of claim 1, wherein at least one carrier board is formed as a double carrier board, which has an individual coil on both sides. ### Claim 8 (depends on 7) The sensor of claim 7, wherein the at least one carrier board formed as a double carrier board has an individual coil of one of the receiving coils on one side and an individual coil of the transmitting coil on the other side. ### Claim 9 (depends on 1) The sensor of claim 1, wherein the top board has precisely four terminal pads, including two terminal pads for the receiving coils and two terminal pads for the transmitting coil. ### Claim 10 (depends on 1) The sensor of claim 1, wherein: at least one of the receiving coils includes an axial conductive track running parallel to the sensor axis; and the top board includes one or more transverse conductive tracks running transverse to the sensor axis for transfer or connection to the axial conductive track. ### Claim 11 A method for detecting an object using an inductive proximity sensor, the method comprising: generating an alternating field using a transmitting coil of the inductive proximity sensor; and sensing, using two receiving coils of the inductive proximity sensor, a change in the alternating field caused by proximity of the object, wherein the inductive proximity sensor has an external diameter of equal to or smaller than 10 mm, the inductive proximity sensor further includes a top board not including coils and configured to act as an interface with terminal pads for connection to circuitry including a generator or oscillator, the transmitting coil is arranged between the two receiving coils, the receiving coils and transmitting coil are formed from a group of at least two individual coils on carrier boards, which are arranged parallel to one another and axially offset as a stack along a common sensor axis, and a winding of the transmitting coil or a receiving coil of the two receiving coils has a cross-sectional geometry in which a ratio of a base width to a height lies in a range of from 0.2 to 0.3. ### Claim 12 (depends on 11) The method of claim 11, wherein the height does not exceed 0.05 mm. ### Claim 13 (depends on 11) The method of claim 11, wherein a number of turns of at least one individual coil of the receiving coils is equal to or greater than 3. ### Claim 14 (depends on 11) The method of claim 11, wherein a number of turns of at least one individual coil of the transmitting coil is equal to or greater than 3. ### Claim 15 (depends on 12) The method of claim 12, wherein the transmitting coil has a number n of individual coils and the two receiving coils together have a number of at least n+1 individual coils. ### Claim 16 (depends on 11) The method of claim 11, wherein at least one carrier board is formed as a double carrier board which has an individual coil on both sides. ### Claim 17 (depends on 16) The method of claim 16, wherein the at least one carrier board formed as a double carrier board has an individual coil of the receiving coil on one side and an individual coil of the transmitting coil on the other side. ### Claim 18 (depends on 11) The method of claim 11, wherein the top board has precisely four terminal pads, including two terminal pads for the receiving coils and two terminal pads for the transmitting coil.