Patent
Rolling bearing unit with load measuring unit
| العنوان: | Rolling bearing unit with load measuring unit |
|---|---|
| Patent Number: | 7,686,516 |
| تاريخ النشر: | March 30, 2010 |
| Appl. No: | 11/597567 |
| Application Filed: | May 12, 2005 |
| مستخلص: | An encoder 12 a characteristic of which is changed alternately at an equal interval in a circumferential direction is supported/fixed onto a hub 4 concentrically with the hub 4. A sensing portion of a sensor 13 supported on the outer ring 3 is positioned in close vicinity to a sensed surface of the encoder 12 to face thereto. Width dimensions of first and second sensed portions provided onto the sensed surface are changed continuously in a direction along which a to-be-sensed load is applied. Since a pattern according to which an output signal of the sensor 13 is changed is changed pursuant to a change of the load, the load is derived by observing this pattern. The output signal is also utilized to sense a rotation speed of the hub 4 in ABS or TCS control. |
| Inventors: | Shibasaki, Kenichi (Kanagawa, JP); Ono, Koichiro (Kanagawa, JP); Yukawa, Kinji (Kanagawa, JP); Aoki, Mamoru (Kanagawa, JP); Ono, Junji (Kanagawa, JP); Chifu, Taketoshi (Kanagawa, JP) |
| Assignees: | NSK Ltd. (Tokyo, JP) |
| Claim: | 1. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use, a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side raceway and a rotary side raceway, which exist on mutually opposing peripheral surfaces of the stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one sensor which is supported on a non-rotated portion in a state that a sensing portion of the at least one sensor is opposed to the sensed surface and an output signal of which is changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signal, wherein a pitch or phase through which the characteristic of the sensed surface is changed along the circumferential direction is changed continuously in response to an acting direction of a to-be-sensed load, and the arithmetic unit has a function of calculating the load based on a pattern according to which the output signal of the at least one sensor is changed, and wherein the to-be-sensed load is a radial load that acts between the stationary side raceway ring and the rotary side raceway ring in a radial direction, the sensed surface includes a side surface of the encoder in an axial direction, a first sensed portion and a second sensed portion having different characteristics mutually are aligned alternately on the sensed surface at an equal interval in the circumferential direction, and a width of the first sensed portion in the circumferential direction is widened toward an outer side in the radial direction and a width of the second sensed portion in the circumferential direction is widened toward an inner side in the radial direction. |
| Claim: | 2. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use, a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side raceway and a rotary side raceway, which exist on mutually opposing peripheral surfaces of the stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one pair of sensors which is supported on a non-rotated portion in a state that a pair of sensing portions of the at least one pair of sensors is opposed to the sensed surface and output signals of which are changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signals, wherein a phase through which the characteristic of the sensed surface is changed along the circumferential direction is changed continuously in response to an acting direction of a to-be-sensed load, and the arithmetic unit has a function of calculating the load based on a phase shift between the output signals, and wherein the to-be-sensed load is a radial load that acts between the stationary side raceway ring and the rotary side raceway ring in a radial direction, the sensed surface includes a side surface of the encoder in an axial direction, a first sensed portion and a second sensed portion having a different characteristic mutually are aligned alternately on the sensed surface at an equal interval in the circumferential direction, a boundary between the first sensed portion and the second sensed portion is inclined to a diameter direction of the encoder and also an inclined direction of the boundary to the diameter direction is set in an opposite direction with respect to a middle portion of the encoder in the diameter direction mutually, and the pair of sensing portions of the at least one pair of sensors is provided to positions separated in the diameter direction of the encoder to put the middle portion in the diameter direction therebetween. |
| Claim: | 3. The rolling bearing unit according to any one of claims 1 to 2 , wherein the encoder is made of a permanent magnet, and one of the first sensed portion and the second sensed portion is an N pole and the other of the first sensed portion and the second sensed portion is an S pole. |
| Claim: | 4. The rolling bearing unit according to any one of claims 1 to 2 , wherein one of the first sensed portion and the second sensed portion is a through hole or a concave hole, and the other of the first sensed portion and the second sensed portion is an interim portion located between neighboring through holes or concave holes in the circumferential direction. |
| Claim: | 5. The rolling bearing unit according to any one of claims 1 to 2 , wherein one of the first sensed portion and the second sensed portion is a convex portion, and the other of the first sensed portion and the second sensed portion is a concave portion located between neighboring convex portions in the circumferential direction. |
| Claim: | 6. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side and rotary side raceway, which exist on mutually opposing peripheral surfaces of the stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one sensor which is supported on a non-rotated portion in a state that a sensing portion of the at least one sensor is opposed to the sensed surface and an output signal of which is changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signal, wherein a pitch or phase through which the characteristic of the sensed surface changed along the circumferential direction is changed continuously in response to an action direction of a to-be-sensed load, and the arithmetic unit has a function of calculating the load based on a pattern according to which the output signal of the at least one sensor is changed, and wherein the to-be-sensed load is a radial load that acts between the stationary side raceway ring and the rotary side raceway ring in a radial direction, the sensed surface includes a side surface of the encoder in an axial direction, a plurality of sensed combination portions each including a pair of individualized portions having a characteristic different from other portions are aligned on the sensed surface at an equal interval in the circumferential direction, and an interval between the pair of individualized portions in the circumferential direction is changed continuously over all sensed combination portions in a same direction of the radial direction. |
| Claim: | 7. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use, a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side raceway and a rotary side raceway, which exist on mutually opposing peripheral surfaces of the stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one sensor which is supported on a non-rotated portion in a state that a sensing portion of the at least one sensor is opposed to the sensed surface and an output signal of which is changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signal, wherein a pitch or phase through which the characteristic of the sensed surface is changed along the circumferential direction is changed continuously in response to an acting direction of a to-be-sensed load and the arithmetic unit has a function of calculating the load based on a pattern according to which the output signal of the at least one sensor is changed, and wherein the to-be-sensed load is an axial load that acts between the stationary side raceway ring and the rotary side raceway ring in an axial direction, the sensed surface includes a peripheral surface of the encoder, a first sensed portion and a second sensed portion having different characteristics mutually are aligned alternately on the sensed surface at an equal interval in the circumferential direction, and a width of the first sensed portion in the circumferential direction is widened toward one end side in the axial direction and a width of the second sensed portion in the circumferential direction is widened toward the other end side in the axial direction. |
| Claim: | 8. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use, a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side raceway and a rotary side raceway, which exist on mutually opposing peripheral surfaces of the stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one pair of sensors which is supported on a non-rotated portion in a state that a pair of sensing portions of the at least one pair of sensors are opposed to the sensed surface and output signals of which are changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signals, wherein a phase through which the characteristic of the sensed surface is changed along the circumferential direction is changed continuously in response to an acting direction of a to-be-sensed load and the arithmetic unit has a function of calculating the load based on a phase shift between the output signals, and wherein the to-be-sensed load is an axial load that acts between the stationary side raceway ring and the rotary side raceway ring in an axial direction, the sensed surface includes a peripheral surface of the encoder, a first sensed portion and a second sensed portion having different characteristics mutually are aligned alternately on the sensed surface at an equal interval in the circumferential direction, a boundary between the first sensed portion and the second sensed portion is inclined to an axial direction of the encoder and also an inclined direction of the boundary to the axial direction is set in an opposite direction with respect to a middle portion of the encoder in the axial direction mutually, and the sensing portions of the at least one pair of sensors are provided to positions separated in the axial direction of the encoder to put the middle portion in the axial direction therebetween. |
| Claim: | 9. The rolling bearing unit according to any one of claims 7 and 8 , wherein the encoder is made of a permanent magnet, and the first sensed portion is an N pole and the second sensed portion is an S pole. |
| Claim: | 10. The rolling bearing unit according to any one of claims 7 and 8 , wherein the first sensed portion is a through hole or a concave hole, and the second sensed portion is an interim portion located between neighboring through holes or concave holes in the circumferential direction. |
| Claim: | 11. The rolling bearing unit according to any one of claims 7 and 8 , wherein the first sensed portion is a convex portion, and the second sensed portion is a concave portion located between neighboring convex portions in the circumferential direction. |
| Claim: | 12. The rolling bearing unit according to claim 11 , wherein the rolling bearing unit is a wheel supporting rolling bearing unit, the stationary side raceway ring is supported/fixed onto a suspension system in a state of use, and the rotary side raceway ring supports/fixes a wheel and rotates together with the wheel. |
| Claim: | 13. The rolling bearing unit according to claim 11 , wherein the rolling bearing unit supports rotatably a spindle of a machine tool onto a housing, an outer ring as the stationary side raceway ring is fitted/fixed into the housing or a portion fixed to the housing in a state of use, and an inner ring as the rotary side raceway ring is fitted/fixed onto the spindle or a portion that rotates together with the spindle. |
| Claim: | 14. The rolling bearing unit according to claim 2 or 8 , wherein the at least one of sensors comprises a plurality of pairs of sensors, each of the pairs of the sensors having said pair of sensing portions, and the pairs of sensing portions of the plurality of pairs of sensors oppose to equally-spaced positions on the sensed surface of the encoder along the circumferential direction. |
| Claim: | 15. The rolling bearing unit according to claim 2 or 8 , wherein the at least one pair of sensors comprises three or more pairs of sensors, each of the pairs of the sensors having said pair of sensing portions, and the pairs of sensing portions of the pairs of sensors oppose to different positions on the sensed surface of the encoder in the circumferential direction respectively, and the arithmetic unit has a function of calculating a momental load applied between the stationary side raceway ring and the rotary side raceway ring. |
| Claim: | 16. A rolling bearing unit comprising: a rolling bearing unit including a stationary side raceway ring not rotated in a state of use, a rotary side raceway ring rotated in a state of use, and a plurality of rolling elements provided between a stationary side raceway and a rotary side raceway, which exist on mutually opposing peripheral surfaces left stationary side raceway ring and the rotary side raceway ring; and a load measuring unit including an encoder which is supported on a part of the rotary side raceway ring concentrically with the rotary side raceway ring and a characteristic of a sensed surface of which is changed alternately along a circumferential direction, at least one sensor which is supported on a non-rotated portion in a state that a sensing portion of the at least one sensor is opposed to the sensed surface and an output signal of which is changed in response to a change in characteristic of the sensed surface, and an arithmetic unit for calculating a load applied between the stationary side raceway ring and the rotary side raceway ring based on the output signal, wherein a pitch or phase through which the characteristic of the sensed surface is changed along the circumferential direction is changed continuously in response to an acting direction of a to-be-sensed load, and the arithmetic unit has a function of calculating the load based on a pattern according to which the output signal of the at least one sensor is changed, and wherein the to-be-sensed load is an axial load that acts between the stationary side raceway ring and the rotary side raceway ring in an axial direction, the sensed surface includes a peripheral surface of the encoder, a plurality of sensed combination portions each including a pair of individualized portions having a characteristic different from other portions are aligned on the sensed surface at an equal interval in the circumferential direction, and an interval between the pair of individualized portions in the circumferential direction is changed continuously over all sensed combination portions in a same direction of the axial direction. |
| Claim: | 17. The rolling bearing unit according to any one of claims 1 , 6 , 7 and 16 , wherein the at least one sensor comprises a plurality of sensors, each of the sensors having said sensing portion, and the sensing portions of the plurality of sensors oppose to equally-spaced positions on the sensed surface of the encoder along the circumferential direction. |
| Claim: | 18. The rolling bearing unit according to any one of claims 1 , 2 , 6 , 7 , 8 and 16 , wherein the rolling bearing unit is a wheel supporting rolling bearing unit, the stationary side raceway ring is supported/fixed onto a suspension system in a state of use, and the rotary side raceway ring supports/fixes a wheel and rotates together with the wheel. |
| Claim: | 19. The rolling bearing unit according to any one of claims 1 , 2 , 6 , 7 , 8 and 16 , wherein the rolling bearing unit supports rotatably a spindle of a machine tool onto a housing, an outer ring as the stationary side raceway ring is fitted/fixed into the housing or a portion fixed to the housing in a state of use, and an inner ring as the rotary side raceway ring is fitted/fixed onto the spindle or a portion that rotates together with the spindle. |
| Claim: | 20. The rolling bearing unit according to any one of claims 1 , 6 , 7 and 16 , wherein the at least on sensor comprises three or more sensors, each of the sensors having said sensing portion, and the sensing portions of the sensors oppose to different positions on the sensed surface of the encoder in the circumferential direction respectively, and the arithmetic unit has a function of calculating a momental load applied between the stationary side raceway ring and the rotary side raceway ring by comparing the output signals of the sensors mutually. |
| Current U.S. Class: | 384/448 |
| Patent References Cited: | 5596189 January 1997 Orton 5967669 October 1999 Ouchi 6619849 September 2003 Katano 6956367 October 2005 Fujikawa et al. 7501811 March 2009 Ono 2004/0056184 March 2004 Steinlechner et al. 28 10 787 September 1978 42 31 332 April 1993 62-3365 January 1987 3-209016 September 1991 2001-21577 January 2001 2004-3918 January 2004 |
| Other References: | Patent Abstracts of Japan, 2003, No. 12, Dec. 5, 2003 & JP 2004 077159 A (Koyo Seiko Co., Ltd.), Mar. 11, 2004. cited by other |
| Primary Examiner: | Hannon, Thomas R |
| Attorney, Agent or Firm: | Sughrue Mion, PLLC |
| رقم الانضمام: | edspgr.07686516 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |