Wireless sensor system and wireless sensor-equipped bearing device

• US 20070030162A1
• Filed: 09/14/2004
• Published: 02/08/2007
• Est. Priority Date: 09/19/2003
• Status: Active Grant

• Current Assignee: NTN Corporation
• Original Assignee: NTN Corporation
• Inventors: Sasaki, Norihiko, Mizutani, Masatoshi, Okada, Koichi
• Granted Patent: US 7,612,665 B2
• Time in Patent Office: Days
• US Class Current: 340/682
• CPC Class Codes: F16C 19/186 with three raceways provided integrally on parts other than race rings, e.g. third generation hubs
• CPC Class Codes: F16C 19/187 with all four raceways integrated on parts other than race rings, e.g. fourth generation hubs
• CPC Class Codes: F16C 19/52 with devices affected by abnormal or undesired conditions
• CPC Class Codes: F16C 2326/02 Wheel hubs or castors
• CPC Class Codes: F16C 41/007 Encoders, e.g. parts with a plurality of alternating magnetic poles
• CPC Class Codes: F16C 41/008 Identification means, e.g. markings, RFID-tags; Data transfer means
• CPC Class Codes: G01M 13/04 Bearings
• CPC Class Codes: G01P 3/443 mounted in bearings bearings F16C
• CPC Class Codes: G01P 3/446 mounted between two axially spaced rows of rolling elements
• CPC Class Codes: G08C 23/04 using light waves, e.g. infrared

Abstract

To provide a wireless sensor system, in which the sensor signal is hardly affected by the 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 (4A, 4B) and a sensor signal receiving unit (5). The wireless sensor unit (4A, 4B) includes a sensor section (6A, 6B) for detecting a target of detection, a digitalizing section (7) for digitalizing a sensor signal thereof, and a sensor signal transmitting section (9A, 9B).

Claims

1. A wireless sensor system which comprises:

one or a plurality of wireless sensor units including a sensor section for detecting a target of detection, a sensor signal transmitting section for transmitting by wireless a sensor signal outputted from the sensor section, and an electric power receiving section for receiving by wireless an electric operating power for driving the sensor section and the sensor signal transmitting section;

a sensor signal receiving section for receiving the sensor signal transmitted from the sensor signal transmitting section; and

an electric power transmitting section for transmitting an electric operating power by wireless to the electric power receiving section;

wherein the wireless sensor unit includes a digitalizing section for digitalizing the sensor signal outputted from the sensor section and the sensor signal transmitting section transmits the digitalized sensor signal.

2. The wireless sensor system as claimed in claim 1, wherein the plurality of the wireless sensor units are provided and wherein the sensor signal receiving section is capable of receiving the sensor signal from the sensor section, which is transmitted from each of the wireless sensor units.

3. The wireless sensor system as claimed in claim 1, wherein the electric power transmitting section is provided in a sensor signal receiving unit having the sensor signal receiving section.

4. 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.

5. 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.

6. 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 magnetic sensor of a magnetoresistance type disposed in face-to-face relation with the pulsar ring.

7. The wireless sensor system as claimed in claim 6, wherein the revolution sensor is a means for generating pulses and wherein the sensor signal digitalized by the digitalizing section is a signal indicative of the period of the pulses.

8. The wireless sensor system as claimed in claim 6, wherein the revolution sensor is a means for generating two or more pulses of different phases and wherein the sensor signal digitalized by the digitalizing section is a signal indicative of the period of the pulses and a direction of revolution.

9. 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.

10. The wireless sensor system as claimed in claim 4, 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.

11. 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.

12. 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.

13. The wireless sensor system incorporated bearing assembly as claimed in claim 12, wherein one of sensors forming respective part of the sensor section is a preload sensor for the bearing assembly.

14. The wireless sensor incorporated bearing assembly as claimed in claim 12, 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 for rotatably supporting a vehicle wheel relative to a vehicle body structure.

15. A wireless sensor system comprising:

one or a plurality of wireless sensor units including a sensor section for detecting a target of detection, a sensor signal transmitting section for transmitting by wireless a sensor signal outputted from the sensor section, and an electric power receiving section for receiving by wireless an electric operating power for driving the sensor section and the sensor signal transmitting section;

a sensor signal receiving section for receiving the sensor signal transmitted from the sensor signal transmitting section; and

an electric power transmitting section for transmitting an electric operating power by wireless to the electric power receiving section;

wherein the wireless sensor unit comprises an electric power accumulating device such as a capacitor or a secondary battery for accumulating the electric power received by the electric power receiving section.

16. A wireless sensor incorporated bearing assembly comprising a rolling bearing assembly which includes an inner member, an outer member, a plurality of rolling elements interposed between the inner member and the outer member, the wireless sensor system as defined in claim 15, and an electric power accumulating device such as, for example, a capacitor or a secondary battery for accumulating the electric power received by the electric power receiving section.

17. The wireless sensor incorporated bearing assembly as claimed in claim 16, 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.

18. The wireless sensor incorporated bearing assembly as claimed in claim 16, 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 for rotatably supporting a vehicle wheel relative to a vehicle body structure.