# US 10,374,733 B2 · Magnetic linear fader > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,733 B2 - Document ID: US10374733B2 - Status: Granted - Kind: B2 - Application number: 16/013,027 - Filed: 2018-06-20 - Published: 2018-10-18 - Granted: 2019-08-06 - Earliest claimed: 2016-03-11 - Assignees: Sound Devices LLC - Applicants: Sound Devices, LLC - Inventors: Matt Anderson; Steven Popovich; Paul Isaacs; Jason McDonald - Web page: https://patentgrep.com/patent/US10374733B2 ## CPC - H04H 60/04: Studio equipment; Interconnection of studios - G01D 5/20: by varying inductance, e.g. by a movable armature - G01R 33/07: Hall effect devices - G01R 33/072: {Constructional adaptation of the sensor to specific applications} - H01F 7/064: {Circuit arrangements for actuating electromagnets (circuit arrangements for obtaining special operating characteristics H01F7/18; driving circuits for electromagnets making use of a switching regulator H01H47/325)} - H02K 41/00: Propulsion systems in which a rigid body is moved along a path due to dynamo-electric interaction between the body and a magnetic field travelling along the path {(electromagnetic launchers F41B6/00)} - H04R 3/00: Circuits for transducers (arrangements for producing a reverberation or echo sound G10K15/08; amplifiers H03F) - H04H: BROADCAST COMMUNICATION (multiplex communication H04J; pictorial communication aspects of broadcast systems H04N) - 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 - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract A linear fader includes a slider that is configured to slide along a rail. The slider includes a magnet. The linear fader also includes a plurality of coils spaced along a length of the rail, one or more sensors configured to detect a position of the slider along the rail, and control circuitry operatively coupled to the plurality of coils and the one or more sensors. The control circuitry is configured to receive a signal corresponding to a first location of the slider from at least one of the one or more sensors, receive a desired location of the slider, and cause a first electrical current to pass through the plurality of coils, thereby generating a force on the slider in a direction toward the desired location. ## Claims ### Claim 1 A linear fader comprising: a slider that is configured to slide along a rail, wherein the slider comprises a magnet; a plurality of coils spaced along a length of the rail, wherein a first portion of the plurality of coils is spaced along a first side of the rail, and wherein a second portion of the plurality of coils is spaced along a second side of the rail; one or more sensors configured to detect a position of the slider along the rail; and control circuitry operatively coupled to the plurality of coils and the one or more sensors, wherein the control circuitry is configured to: receive a first location of the slider from at least one of the one or more sensors; receive a signal corresponding to a desired location of the slider; and cause a first electrical current to pass through the plurality of coils, thereby generating a force on the slider in a direction toward the desired location. ### Claim 2 (depends on 1) The linear fader of claim 1, wherein the plurality of coils are configured in a three-phase arrangement, and wherein the first electrical current is a three-phase electrical current. ### Claim 3 (depends on 1) The linear fader of claim 1, wherein the control circuitry is further configured to: receive a second location of the slider from at least one of the one or more sensors; and transmit, to an external circuit, a signal indicating the second location of the slider. ### Claim 4 (depends on 3) The linear fader of claim 3, wherein the signal indicating the second location of the slider comprises an indication of a fade effect to be applied to a signal corresponding to the linear fader. ### Claim 5 (depends on 1) The linear fader of claim 1, wherein the signal corresponding to the desired location comprises a signal attribute, and wherein the control circuitry is further configured to determine the desired location based on the signal attribute. ### Claim 6 (depends on 1) The linear fader of claim 1, further comprising a knob attached to the slider. ### Claim 7 (depends on 6) The linear fader of claim 6, further comprising a housing that houses the slider, the plurality of coils, and the one or more sensors. ### Claim 8 (depends on 1) The linear fader of claim 1, wherein each of the one or more sensors comprises a magnetic sensor configured to detect a magnetic field of the magnet. ### Claim 9 (depends on 8) The linear fader of claim 8, wherein each magnetic sensor comprises a Hall-effect sensor. ### Claim 10 (depends on 1) The linear fader of claim 1, wherein the one or more sensors are spaced along at least one side of the rail. ### Claim 11 (depends on 1) The linear fader of claim 1, wherein a first portion of the first electrical current passes through the first portion of the plurality of coils, wherein a second portion of the first electrical current passes through the second portion of the plurality of coils, and wherein a first force of a first magnetic field generated by the first portion of the electrical current applied to the magnet balances a second force of a second magnetic field generated by the second portion of the first electrical current applied to the magnet. ### Claim 12 (depends on 11) The linear fader of claim 11, wherein the magnet comprises a plurality of north poles and a plurality of south poles. ### Claim 13 (depends on 1) The linear fader of claim 1, wherein the plurality of coils are formed in a printed circuit board. ### Claim 14 (depends on 1) The linear fader of claim 1, wherein the control circuitry is further configured to control a second electrical current that passes through the plurality of coils, wherein an opposing magnetic field of the second electrical current through the plurality of coils resists movement of the slider along the rail, and wherein the resistance of movement simulates a desired feel-effect. ### Claim 15 (depends on 14) The linear fader of claim 14, wherein the control circuitry is further configured to receive a signal indicative of the desired feel-effect, and wherein the control circuitry is configured to control the second electrical current in response to receiving the signal indicative of the desired feel-effect. ### Claim 16 (depends on 15) The linear fader of claim 15, wherein the desired feel-effect comprises at least one of a coggy feel, a notchy feel, an end-stop feel, or a friction of movement feel. ### Claim 17 A method comprising: receiving, from at least one sensor, a location of a slider along a rail, wherein each sensor is configured to sense a magnetic field of the slider; receiving, from a remote processing circuit, a signal corresponding to a desired location of the slider; and causing a first electrical current to pass through a plurality of coils that are spaced along a length of the rail, wherein a first portion of the plurality of coils is spaced along a first side of the rail, and wherein a second portion of the plurality of coils is spaced along a second side of the rail, wherein the first electrical current generates a magnetic field that applies a force on the slider, and wherein the force on the slider is in a direction toward the desired location. ### Claim 18 (depends on 17) The method of claim 17, further comprising: receiving a second location of the slider from at least one sensor; and transmitting, to the remote circuit, a signal indicating the second location of the slider. ### Claim 19 (depends on 17) The method of claim 17, wherein causing the first electrical current to pass through the plurality of coils comprises: causing a first portion of the first electrical current to pass through a first portion of the plurality of coils; and causing a second portion of the first electrical current to pass through a second portion of the plurality of coils, and wherein a first force of a first magnetic field generated by the first portion of the first electrical current applied to the magnet balances a second force of a second magnetic field generated by the second portion of the first electrical current applied to the magnet. ### Claim 20 (depends on 17) The method of claim 17, further comprising controlling a second electrical current that passes through the plurality of coils, wherein an opposing magnetic field of the second electrical current through the plurality of coils resists movement of the slider along the rail.