SENSING DEVICE AND BEARING COMPONENT

Abstract

A sensing device for a bearing and a bearing component. The sensing device includes a sensing body for mounting into the bearing by a press fit. The sensing body is provided with: a sensing measurement module having a pressure sensor for measuring the load of the bearing and a temperature sensor for measuring the temperature of the sensing device, and the measured load is corrected using the measured temperature; a wireless communication module used for wirelessly transmitting bearing information from the sensing measurement module; and a wireless power supply module used for supplying power for the sensing measurement module and the wireless communication module. The bearing component includes a bearing and the sensing device.

Claims

1. A sensing device for a bearing, the sensing device comprising: a sensing body for mounting into the bearing by a press fit, the sensing body is provided with: a sensing measurement module comprising a pressure sensor configured for measuring a load of the bearing and a temperature sensor configured for measuring a temperature of the sensing device, wherein the sensing measurement module is configured to correct a measured load is using the measured temperature; a wireless communication module configured for wirelessly transmitting bearing information from the sensing measurement module; and a wireless power supply module configured for supplying power for the sensing measurement module and the wireless communication module.

2. The sensing device according to claim 1, wherein the sensing body comprises a pin-shaped base and a printed circuit board , the base is mountable into the bearing by a press fit, and the printed circuit board at least partially mounts elements of three of the sensing measurement modules to the base .

3. The sensing device according to claim 2, wherein the wireless communication module comprises an RFID chip arranged on the printed circuit board and an antenna arranged on the base , and the RFID chip and the antenna are configured for conducting wireless communication with communication counterpart equipment arranged outside the bearing.

4. The sensing device according to claim 3, wherein the pressure sensor comprises at least two strain gauges the at least two strain gauges are arranged in a region of the base for realizing the press fit, one of the at least two strain gauges is arranged on an axial end face of the base , and an other of the at least two strain gauges is arranged on a peripheral surface of the base at least partially extending in an axial direction.

5. The sensing device according to claim 4, wherein a measurement circuit and a measurement signal processing circuit for the strain gauges are arranged on the printed circuit board.

6. The sensing device according to claim 5, wherein the RFID chip includes an analog-to-digital conversion circuit in the measurement signal processing circuit.

7. The sensing device according to claim 4, wherein the temperature sensor is provided on the RFID chip.

8. The sensing device according to claim 4, wherein the antenna is arranged on an axial end face of the base , the axial end face being opposite to an axial end face on which the strain gauge is arranged.

9. The sensing device according to claim 8, further comprising an antenna cover on an outer side of the antenna.

10. The sensing device according to claim 9, further comprising a sealing elastomer between the antenna and the antenna cover.

11. The sensing device according to claim 3, wherein the antenna is configured as a power receiving antenna of the wireless power supply module, so that energy supplied by power supply counterpart equipment arranged outside the bearing is wirelessly obtainable.

12. The sensing device according to claim 3, wherein the RFID chip includes a power management circuit of the wireless power supply module.

13. The sensing device according to claim 2, further comprising a channel for accommodating electrical conductors arranged inside the base .

14. The sensing device according to claim 2, wherein the base comprises an auxiliary connection structure configured for connection with a bearing member of the bearing.

15. The sensing device according to claim 2, wherein the base is made of a same material as the bearing member on which the sensing device is mounted.

16. The sensing device according to claim 2, wherein the sensing device is at least partially encapsulated.

17. A bearing component, comprising a bearing and the sensing device according to claim 1.

18. The bearing component according to claim 17, wherein the sensing device is mounted in a mounting hole of an outer ring or an inner ring of the bearing, and the mounting hole extends along an axial direction of the bearing; or, the sensing device is mounted in a mounting hole of a rolling element of the bearing, and the mounting hole extends along a central axis of the rolling element.

19. A sensing system for a bearing, the sensing system comprising the sensing device according to claim 1 and sensing device counterpart equipment arranged outside the bearing.

20. A bearing assembly, comprising a bearing and the sensing system according to claim 19.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Preferred embodiments of the present disclosure will be schematically illustrated below with reference to drawings. Drawings are as follows:

[0044] FIG. 1 is a partial cross-sectional view of a bearing component according to a preferred embodiment;

[0045] FIG. 2 is a perspective view of the sensing device in the bearing component according to FIG. 1; and

[0046] FIG. 3 is a cross-sectional view of the sensing device according to FIG. 2, obtained by sectioning along an axial direction thereof.

DETAILED DESCRIPTION

[0047] FIG. 1 shows a partial cross-sectional view of a bearing component according to a preferred embodiment. The bearing component comprises a bearing designed as a tapered roller bearing and a sensing device 50. As shown in FIG. 1, the bearing comprises an outer ring 20, an inner ring 10, and a retainer 40 and a tapered roller type rolling element 30 arranged between the outer ring 20 and the inner ring 10.

[0048] As shown in FIG. 1, the inner ring 10 of the bearing is configured with a mounting hole for accommodating a sensing device. The mounting hole is configured as a blind hole and extends parallel to a central axis of the bearing. In this embodiment, the sensing device 50 is implemented as a sensing pin for wireless communication and wireless power supply.

[0049] FIG. 2 and FIG. 3 respectively show a perspective view of the sensing device 50 in the bearing component according to FIG. 1 and a cross-sectional view obtained by sectioning the sensing device 50 along the axial direction thereof. As shown in FIG. 2 and FIG. 3, the sensing device 50 comprises a sensing body for mounting into the inner ring 10 of the bearing. The sensing body is configured with a sensing measurement module, a wireless communication module and a wireless power supply module.

[0050] The sensing body comprises a pin-shaped base 6 and a printed circuit board 1. The pin-shaped base 6 has a substantially circular cross-section. The pin-shaped base 6 is made of the same material as the inner ring 10, thereby minimizing the effect of temperature-induced size changes of the material. The peripheral surface of the base 6 is partially configured with a plane on which the printed circuit board 1 is arranged.

[0051] Referring to FIGS. 1, 2 and 3, the sensing body is fixed in the mounting hole of the inner ring 10 with a pin-shaped base 6 by a press fit. Furthermore, when the base 6 is mounted, the axial end of the base at the opening of the mounting hole is also provided with a step part, and the peripheral surface of which is provided with an external thread not shown in detail, wherein the external thread can match an internal thread configured in the stepped mounting hole to achieve an auxiliary threaded connection.

[0052] The sensing measurement module comprises a pressure sensor for measuring the axial and radial loads of the bearing and a temperature sensor for measuring the temperature of the sensing device. The pressure sensor comprises two strain gauges, namely a measurement strain gauge 2 and a reference strain gauge 3 which are arranged in a press-fit region. The measurement strain gauge 2 and the reference strain gauge 3 are here preferably semiconductor strain gauges with a large resistance strain and a high strain sensitivity. The measurement strain gauge 2 is attached to an axial end face, facing the hole bottom of the mounting hole, of the base 6. Here, the longitudinal direction of the measurement strain gauge 2 is aligned with the radial direction of the base 6. In the region where the press-fit of the base 6 is achieved, a plane is partially configured on the peripheral surface of the base 6, wherein the plane is perpendicular to the axial end face of the base 6, to which the reference strain gauge 3 is attached. Here, the plane in which the reference strain gauges 3 are arranged and the plane in which the printed circuit board 1 is arranged are parallel to each other at the base 6. Here, the longitudinal direction of the reference strain gauge 3 is parallel to a central axis of the base 6. The measurement strain gauge 2 and the reference strain gauge 3 are respectively connected to the measurement printed circuit board 1 by electrical conductors 4. Here, a channel for accommodating and guiding the electrical conductors 4 is configured in the base 6. The printed circuit board 1 is provided with a measurement circuit for strain gauges, an amplification circuit, and an analog-to-digital conversion circuit, wherein the measurement circuit is a Wheatstone bridge here, and the analog-to-digital conversion circuit is provided by an RFID chip arranged on the printed circuit board 1. During the measurement process, the strain on the base 6 caused by the bearing load causes a resistance change of the measurement strain gauge 2, wherein the resistance change can be detected by the Wheatstone bridge measurement circuit and subsequently amplified by the amplification circuit and adjusted to fit the analog-to-digital conversion circuit in the RFID sensing chip. The RFID chip also provides a temperature sensor, from which the measured temperature can be used to correct the load measured by the pressure sensor. In this way, measurement errors caused by the influence of the temperature on the strain gauges and electrical conductors can be reduced. Here, the reference strain gauge 3, the electrical conductors 4, and the printed circuit board 1, together with the base 6, may be encapsulated by plastic.

[0053] The wireless communication module comprises the above-mentioned RFID chip arranged on the printed circuit board 1 and an antenna 5 arranged on an axial end face of the base 6, wherein the axial end face on which the antenna 5 is arranged is opposite to the axial end face on which the measurement strain gauge 2 is arranged. The antenna 5 is connected to the printed circuit board 1, in particular the RFID chip, by electrical conductors 4. The electrical conductors 4 are accommodated in a channel inside the base 6. Here, the RFID chip and the antenna 5 together constitute an RFID tag, and the communication counterpart equipment arranged outside the bearing comprises an RFID reader/writer, which can perform wireless data communication with the RFID tag. Here, the bearing information provided by the sensing measurement module is modulated to a carrier RF electromagnetic wave and transmitted by the antenna 5, so that the load condition of the bearing can be monitored wirelessly. The antenna 5 is here preferably a ceramic antenna, which can obtain a large antenna gain with a small size. An antenna cover 7 is provided on an outer side of the antenna 5. The antenna cover 7 is mounted on the base 6, for example, by a threaded connection. The antenna cover 7 is made of plastic, such as ABS, PPS, or PTFE, which can be penetrated by low power radio frequency signals. A sealing elastomer, in particular a sealing rubber, is provided between the antenna 5 and the antenna cover 7, so that the antenna 5 can be better protected.

[0054] The wireless power supply module comprises a power receiving antenna and a power management circuit. Here, the antenna 5 used for an RFID tag of the wireless communication module can be used as a power receiving antenna of the wireless power supply module. The RFID chip may provide a power management circuit. When the power supply antenna of the power supply counterpart equipment emits electromagnetic waves, the electromagnetic waves radiate to the antenna 5 through the antenna cover 7 and a sealing elastic part, wherein the antenna 5 acts as a power receiving antenna to obtain energy from the electromagnetic waves. The obtained energy may be stored in a capacitor and processed by the power management circuit to provide a stable power supply.

[0055] Thanks to the highly integrated RFID chip and the strain gauges with high resistance and high sensitivity, the power consumption of the sensing device can be reduced to several hundred microwatts or below. This is very important for the design of a passive wireless sensing device since it is closely related to the effective distance. In an open environment, the effective distance of the sensing device 50 according to this embodiment may be 5 meters or more, which makes the sensing device suitable for most applications. In addition, as the sensing device uses the wireless communication module and the wireless power supply module, the sensing device can provide the bearing load information in real time when arranged to a rotating member of the bearing. This also makes it possible for the sensing device to perform load measurements at various positions in the circumferential direction of the bearing during rotation with the rotating member. Therefore, the measurement requirements can be satisfied by providing only one such sensing device in each bearing.

[0056] Although possible embodiments have been described illustratively in the above description, it should be understood that there are still a large number of embodiment variations through combinations of all known technical features and embodiments as well as those are readily apparent to those skilled in the art. In addition, it should be further understood that the exemplary embodiments are just examples and shall not in any way limit the scope of protection, application and construction of the present disclosure. The foregoing description is more intended to provide those skilled in the art with a technical guide for converting at least one exemplary embodiment, in which various changes, especially changes in the functions and structures of the components, can be made as long as they do not depart from the scope of protection of the claims.

LIST OF REFERENCE NUMERALS

[0057] TABLE-US-00001 10 Inner ring 20 Outer ring 30 Rolling element 40 Retainer 50 Sensing pin of sensing device 1 Printed circuit board 2 Strain gauge 3 Strain gauge 4 Electrical conductor 5 Antenna 6 Base 7 Antenna cover