# US 7,612,665 B2 · Wireless sensor system and bearing assembly having built-in wireless sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,612,665 B2 - Document ID: US7612665B2 - Status: Granted - Kind: B2 - Application number: 10/572,308 - Filed: 2004-09-14 - Published: 2007-02-08 - Granted: 2009-11-03 - Earliest claimed: 2003-09-19 - Assignees: Ntn Corporation - Inventors: Koichi Okada; Masatoshi Mizutani; Norihiko Sasaki - Web page: https://patentgrep.com/patent/US7612665B2 ## CPC - F16C 41/008: {Identification means, e.g. markings, RFID-tags; Data transfer means} - F16C 19/52: with devices affected by abnormal or undesired conditions - G01M 13/04: Bearings - G01P 3/443: {mounted in bearings (bearings F16C)} - G01P 3/446: {mounted between two axially spaced rows of rolling elements} - G08C 23/04: using light waves, e.g. infrared - F16C 19/186: {with three raceways provided integrally on parts other than race rings, e.g. third generation hubs} - F16C 19/187: {with all four raceways integrated on parts other than race rings, e.g. fourth generation hubs} - F16C 41/007: {Encoders, e.g. parts with a plurality of alternating magnetic poles} - F16C 2326/02: Wheel hubs or castors - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) - G08C: TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS (fluid pressure transmitting systems F15B; mechanical means for transferring the output of a sensing member into a different variable G01D5/00; mechanical control systems G05G) ## Abstract A wireless sensor system in which the sensor signal is hardly affected by disturbance and therefore has an increased reliability, which can be constructed light-weight and compact in structure inclusive of the electric power system and in which communication is possible at all times, and a wireless sensor incorporated bearing assembly of a light-weight and compact structure utilizing such wireless sensor system. This wireless sensor system includes a wireless sensor unit and a sensor signal receiving unit. The wireless sensor unit includes a sensor section to detect a target of detection, a digitalizing section to digitalize a sensor signal thereof, and a sensor signal transmitting section. ## Claims ### Claim 1 A wireless sensor system comprising: one or a plurality of wireless sensor units including a sensor section to detect a target of detection, a sensor signal transmitting section to wirelessly transmit a sensor signal outputted from the sensor section, and an electric power receiving section to wirelessly receive an electric operating power to drive the sensor section and the sensor signal transmitting section; a sensor signal receiving section to receive the sensor signal transmitted from the sensor signal transmitting section; and an electric power transmitting section to wirelessly transmit an electric operating power to the electric power receiving section, wherein the wireless sensor unit includes a digitalizing section to digitalize the sensor signal outputted from the sensor section and the sensor signal transmitting section transmits the digitalized sensor signal, wherein the electric power transmitting section is provided in a sensor signal receiving unit having the sensor signal receiving section. ### Claim 2 (depends on 1) The wireless sensor system as claimed in claim 1, wherein the plurality of the wireless sensor units are provided, and the sensor signal receiving section receives the sensor signal from the sensor section, which is transmitted from each of the wireless sensor units. ### Claim 3 (depends on 1) The wireless sensor system as claimed in claim 1, wherein the wireless sensor unit includes a plurality of sensors forming respective parts of the sensor section. ### Claim 4 (depends on 1) The wireless sensor system as claimed in claim 1, wherein a sensor forming the sensor section is at least one of a revolution sensor, an acceleration sensor, a vibration sensor, a temperature sensor, a load sensor, a torque sensor or a preload sensor for a bearing assembly. ### Claim 5 (depends on 1) The wireless sensor system as claimed in claim 1, wherein one of the sensor sections includes a revolution sensor comprising a pulsar ring and a magnetoresistance magnetic sensor disposed in face-to-face relation with the pulsar ring. ### Claim 6 (depends on 5) The wireless sensor system as claimed in claim 5, wherein the revolution sensor is a means for generating pulses, and the sensor signal digitalized by the digitalizing section is a signal indicative of the period of the pulses. ### Claim 7 A wireless sensor system comprising: one or a plurality of wireless sensor units including a sensor section to detect a target of detection, a sensor signal transmitting section to wirelessly transmit a sensor signal outputted from the sensor section, and an electric power receiving section to wirelessly receive an electric operating power to drive the sensor section and the sensor signal transmitting section; a sensor signal receiving section to receive the sensor signal transmitted from the sensor signal transmitting section; and an electric power transmitting section to wirelessly transmit an electric operating power to the electric power receiving section, wherein the wireless sensor unit includes a digitalizing section to digitalize the sensor signal outputted from the sensor section and the sensor signal transmitting section transmits the digitalized sensor signal, one of the sensor sections includes a revolution sensor comprising a pulsar ring and a magnetoresistance magnetic sensor disposed in face-to-face relation with the pulsar ring, the revolution sensor is a means for generating two or more pulses of different phases, and the sensor signal digitalized by the digitalizing section is a signal indicative of the period of the pulses and a direction of revolution. ### Claim 8 (depends on 2) The wireless sensor system as claimed in claim 2, wherein each of the wireless sensor units is designed to allow the sensor signal transmitting section to transmit, in addition to the sensor signal, an identifying signal indicative of the individual wireless sensor unit. ### Claim 9 (depends on 3) The wireless sensor system as claimed in claim 3, wherein the wireless sensor unit is designed to transmit, in addition to the sensor signal, an identifying number indicative of the individual sensor forming a part of the sensor section. ### Claim 10 (depends on 1) The wireless sensor system as claimed in claim 1, wherein the sensor signal transmitting section transmits the sensor signal by means of a spread spectrum communication scheme. ### Claim 11 (depends on 1) A wireless sensor system incorporated bearing assembly comprising a wireless sensor unit employed in the wireless sensor system as defined in claim 1, the wireless sensor unit being mounted on a bearing assembly. ### Claim 12 (depends on 11) The wireless sensor system incorporated bearing assembly as claimed in claim 11, wherein one of sensors forming respective part of the sensor section is a preload sensor for the bearing assembly. ### Claim 13 (depends on 11) The wireless sensor incorporated bearing assembly as claimed in claim 11, wherein the bearing assembly includes an outer member having a plurality of raceways, an inner member having raceways aligned with the raceway in the outer member, and a plurality of rows of rolling elements interposed between the raceways in the outer member and the raceways in the inner member, respectively, which assembly is a wheel support bearing assembly to rotatably support a vehicle wheel relative to a vehicle body structure. ### Claim 14 A wireless sensor system comprising: one or a plurality of wireless sensor units including a sensor section to detect a target of detection, a sensor signal transmitting section to wirelessly transmit a sensor signal outputted from the sensor section, and an electric power receiving section to wirelessly receive an electric operating power to drive the sensor section and the sensor signal transmitting section; a sensor signal receiving section to receive the sensor signal transmitted from the sensor signal transmitting section; and an electric power transmitting section to wirelessly transmit an electric operating power to the electric power receiving section, wherein the wireless sensor unit comprises an electric power accumulating device or a secondary battery to accumulate the electric power received by the electric power receiving section, and the electric power transmitting section is provided in a sensor signal receiving unit having the sensor signal receiving section. ### Claim 15 A wireless sensor incorporated bearing assembly including a rolling bearing assembly comprising: an inner member; an outer member a plurality of rolling elements interposed between the inner member and the outer member; a wireless sensor system including one or a plurality of wireless sensor units including a sensor section to detect a target of detection, a sensor signal transmitting section to wirelessly transmit a sensor signal outputted from the sensor section, and an electric power receiving section to wirelessly receive an electric operating power to drive the sensor section and the sensor signal transmitting section, a sensor signal receiving section to receive the sensor signal transmitted from the sensor signal transmitting section, and an electric power transmitting section to wirelessly transmit an electric operating power to the electric power receiving section, wherein the wireless sensor unit comprises an electric power accumulating device or a secondary battery to accumulate the electric power received by the electric power receiving section; and an electric power accumulating device or a secondary battery to accumulate the electric power received by the electric power receiving section. ### Claim 16 (depends on 15) The wireless sensor incorporated bearing assembly as claimed in claim 15, wherein the sensor is operable to detect, as a target of detection, one of revolution of the rolling bearing assembly, temperature, acceleration, load, torque or bearing preload. ### Claim 17 (depends on 15) The wireless sensor incorporated bearing assembly as claimed in claim 15, wherein the rolling bearing assembly comprises an outer member having a plurality of raceways, an inner member having raceways aligned with the raceways referred to above, respectively, and a plurality of rolling elements interposed between the raceways in the outer member and the raceways in the inner member, respectively, the rolling bearing assembly being a wheel support bearing assembly to rotatably support a vehicle wheel relative to a vehicle body structure.