Wheel force measuring hub assembly

• US 5,894,094 A
• Filed: 07/07/1997
• Issued: 04/13/1999
• Est. Priority Date: 07/06/1996
• Status: Expired due to Fees

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Meier, Hubert, Kuchler, Maximilian, Ferrufino-Camacho, David-Alfredo, Nohl, Friedrich
• Primary Examiner(s): Noori, Max H.
• Application Number:
  US08/889,155
• Time in Patent Office: 645 Days
• Field of Search: 73/862.041, 73/862.042, 73/862.043, 73/862.044, 73/862.045, 73/146
• US Class Current: 73/862.044
• CPC Class Codes: G01L 1/2262 involving simple electrical bridges
• CPC Class Codes: G01L 5/1627 of strain gauges using piezoresistors G01L5/162
• CPC Class Codes: G01L 5/20 for measuring wheel side-thrust

Abstract

A wheel force measuring hub assembly has a measuring value sensor assembly and comprises an exterior ring part and an interior ring part. A wheel rim is attachable on the exterior ring part. The interior ring part is attachable to a wheel axle. Both ring parts are connected with one another by way of radially extending measuring webs on which strain gauges are arranged for determining forces and torques to be measured. The strain gauges are configured to determine the three mutually perpendicular axial occurring forces Fx, Fy and Fz as well as pertaining torques Mx, My and Mz. The strain gauges are arranged, aligned and connected with one another for determining all forces and torques by way of the shearing strains occurring in the case of a load on a wheel being monitored.

Claims

1. Wheel force measuring hub assembly comprising:

an exterior ring part adapted to be mounted at a wheel rim,

an interior ring part adapted to be mounted at a vehicle axle,

a plurality of radially extending measuring webs connecting the exterior ring part and the interior ring part,

and strain gauges arranged on the measuring webs for determining forces, including torques acting on the webs,

wherein said strain gauges are configured such that wheel forces F_x, F_y, F_z, M_x, M_y and M_z are determined exclusively by way of shearing strains on said strain gauges to decouple individual force components from one another.

2. Wheel force measuring hub assembly according to claim 1, wherein said strain gauges are configured and arranged to provide six separate signals representing wheel forces along and around three mutually perpendicular wheel axes.

3. Wheel force measuring hub assembly according to claim 1, wherein respective openings are arranged in said webs in an area of respective transitions between the webs and the exterior ring part.

4. Wheel force measuring hub assembly according to claim 2, wherein respective openings are arranged in said webs in an area of respective transitions between the webs and the exterior ring part.

5. Wheel force measuring hub assembly according to claim 3, wherein said respective openings are in the form of oblong holes.

6. Wheel force measuring hub assembly according to claim 4, wherein said respective openings are in the form of oblong holes.

7. Wheel force measuring hub assembly according to claim 3, wherein the length and dimensioning of the openings is coordinated such that a separation of forces and torques is achieved as well as a high measuring sensitivity.

8. Wheel force measuring hub assembly according to claim 4, wherein the length and dimensioning of the openings is coordinated such that a separation of forces and torques is achieved as well as a high measuring sensitivity.

9. Wheel force measuring hub assembly according to claim 1, wherein a transmitting device is provided which transmits data obtained by the strain gauges to a vehicle-fixed part.

10. Wheel force measuring hub assembly according to claim 1, wherein a transmitting device is provided which transmits said signals to a vehicle fixed part.

11. Wheel force measuring hub assembly according to claim 9, wherein the transmitting device is an infrared telemetry transmitting device.

12. Wheel force measuring hub assembly according to claim 10, wherein the transmitting device is an infrared telemetry transmitting device.

13. Wheel force measuring hub assembly according to claim 1, wherein current supply is provided to said strain gauges by way of induction loops.

14. Wheel force measuring hub assembly according to claim 1, wherein an installation space in the interior ring part is hermetically sealed for accommodating an electronic control and analysis system.

15. Wheel force measuring hub assembly according to claim 14, wherein the electronic control and analysis system is operable to convert wheel forces in real-time and on-line from rotating system of coordinates of the wheel to a system of coordinates of a vehicle on which the wheel is mounted.

16. Wheel force measuring hub assembly according to claim 1, wherein a control and analysis system is accommodated in the interior ring part for processing signals representing the wheel forces.

17. Wheel force measuring hub assembly according to claim 1, wherein said strain gauges include longitudinal force measuring strain gauges which are arranged on the measuring webs disposed perpendicularly with respect to a vehicle driving direction and on measuring web surfaces which are aligned in parallel to a radial plane of the hub assembly sensor.

18. Wheel force measuring hub assembly according to claim 17, wherein four measuring webs 14 are provided, and

wherein the longitudinal force measuring strain gauges are connected in a full bridge circuit and, in the four branches of the full bridge circuit, two series-connected longitudinal force measuring strain gauges are provided, two longitudinal force measuring strain gauges of one branch being arranged on mutually opposite surfaces of a respective measuring web.

19. Wheel force measuring hub assembly according to claim 1, wherein said strain gauges include wheel contact force measuring strain gauges which are arranged on the measuring webs aligned in a vehicle driving direction and on measuring web surfaces which are aligned in parallel to a radial plane of the hub assembly.

20. Wheel force measuring hub assembly according to claim 19, wherein four measuring webs are provided, and

wherein the wheel contact force measuring strain gauges are connected in a full bridge circuit and, in the four branches of the full bridge circuit, two series-connected contact force measuring strain gauges respectively are arranged, the two strain gauges of one branch being provided on mutually opposite surfaces of a measuring web.

21. Wheel force measuring hub assembly according to claim 1, wherein said strain gauges include wheel lateral force measuring strain gauges which are arranged on all measuring webs and are arranged there on surfaces which are each perpendicular to a radial direction of the hub assembly.

22. Wheel force measuring hub assembly according to claim 21, wherein four measuring webs are provided, and

wherein the wheel lateral force measuring strain gauges are connected to a full bridge circuit and two series-connected wheel lateral force measuring strain gauges respectively are connected in parallel in a branch of the full bridge circuit, the two wheel lateral force measuring strain gauges being arranged in a respective series connection on opposite surfaces of one measuring web respectively and the two wheel lateral force measuring strain gauges of a parallel connection of the respective series connections being disposed perpendicularly on one another in measuring webs assigned to a branch of the full bridge.

23. Wheel force measuring hub assembly according to claim 1, wherein the strain gauges include camber torque measuring strain gauges which are arranged on the measuring webs arranged perpendicularly to the driving direction and on surfaces which are each perpendicular to a radial axis of the hub assembly.

24. Wheel force measuring hub assembly according to claim 23, wherein four measuring webs are provided, and

wherein the camber torque measuring strain gauges are connected in a full bridge circuit, four camber torque measuring strain gauges being connected in series in each branch of the full bridge circuit, of which two camber torque measuring strain gauges respectively are arranged on opposite sides of a measuring web.

25. Wheel force measuring hub assembly according to claim 1, wherein the strain gauges include return torque measuring strain gauges which are arranged on measuring webs aligned in wheel driving directions and on measuring web surfaces which are each perpendicular with respect to a radial direction of the hub assembly.

26. Wheel force measuring hub assembly according to claim 25, wherein four measuring webs are provided, and

wherein the return torque measuring strain gauges are each connected in a full bridge circuit and four of the torque strain gauges are connected in series in each branch of the full bridge circuit, of which two return torque measuring strain gauges respectively are arranged on two opposite sides of a measuring web.

27. Wheel force measuring hub assembly according to claim 1, wherein the strain gauges include braking torque measuring strain gauges which are arranged on all measuring webs and on measuring web surfaces which are each parallel to a radial plane of the hub assembly.

28. Wheel force measuring hub assembly according to claim 27, wherein four measuring webs are provided, and

wherein the braking torque measuring strain gauges are connected in a full bridge circuit and four braking torque measuring strain gauges are connected in series in each branch of the full bridge circuit, of which two braking torque measuring strain gauges are arranged on mutually opposite sides of a measuring web and the other two strain gauges are arranged on mutually opposite sides of a measuring web angularly offset by 90°

.

29. Wheel force measuring hub assembly according to claim 1, wherein the strain gauges arranged on the measuring webs are covered.

30. Wheel force measuring hub assembly according to claim 1, wherein individual strain gauges are connected to respective bridge circuits on a ring-shaped plate bar.

31. Wheel force measuring hub assembly according to claim 1, wherein a total of four measuring webs are provided which are each angularly offset by 90°

.

32. Wheel force measuring hub assembly according to claim 17, wherein said strain gauges include wheel contact force measuring strain gauges which are arranged on the measuring webs aligned in a vehicle driving direction and on measuring web surfaces which are aligned in parallel to a radial plane of the hub assembly.

33. Wheel force measuring hub assembly according to claim 17, wherein said strain gauges include wheel lateral force measuring strain gauges which are arranged on all measuring webs and are arranged there on surfaces which are each perpendicular to a radial direction of the hub assembly.

34. Wheel force measuring hub assembly according to claim 17, wherein the strain gauges include camber torque measuring strain gauges which are arranged on the measuring webs arranged perpendicularly to the driving direction and on surfaces which are each perpendicular to a radial axis of the hub assembly.

35. Wheel force measuring hub assembly according to claim 17, wherein the strain gauges include return torque measuring strain gauges which are arranged on measuring webs aligned in wheel driving directions and on measuring web surfaces which are each perpendicular with respect to a radial direction of the hub assembly.

36. Wheel force measuring hub assembly according to claim 17, wherein the strain gauges include braking torque My measuring strain gauges which are arranged on all measuring webs and on measuring web surfaces which are each parallel to a radial plane of the hub assembly.

37. Wheel force measuring hub assembly according to claim 32, wherein said strain gauges include wheel strain gauges which are arranged on all measuring webs and are arranged there on surfaces which are each perpendicular to a radial direction of the hub assembly.

38. Wheel force measuring hub assembly according to claim 32, wherein four measuring webs are provided, and

wherein the wheel lateral force measuring strain gauges are connected to a full bridge circuit and two series-connected wheel lateral force measuring strain gauges respectively are connected in parallel in a branch of the full bridge circuit, the two wheel lateral force measuring strain gauges being arranged in a respective series connection on opposite surfaces of one measuring web respectively and the two wheel lateral force measuring strain gauges of a parallel connection of the respective series connections being disposed perpendicularly on one another in measuring webs assigned to a branch of the full bridge.

39. Wheel force measuring hub assembly according to claim 32, wherein the strain gauges include return torque measuring strain gauges which are arranged on measuring webs aligned in wheel driving directions and on measuring web surfaces which are each perpendicular with respect to a radial direction of the hub assembly.

40. Wheel force measuring hub assembly according to claim 32, wherein the strain gauges include braking torque measuring strain gauges which are arranged on all measuring webs and on measuring web surfaces which are each parallel to a radial plane of the hub assembly.

41. Wheel force measuring hub assembly according to claim 37, wherein the strain gauges include return torque measuring strain gauges which are arranged on measuring webs aligned in wheel driving directions and on measuring web surfaces which are each perpendicular with respect to a radial direction of the hub assembly.

42. Wheel force measuring hub assembly according to claim 41, wherein the strain gauges include braking torque measuring strain gauges which are arranged on all measuring webs and on measuring web surfaces which are each parallel to a radial plane of the hub assembly.

43. Wheel force measuring hub assembly according to claim 42, wherein at least one Hall sensor is provided which interacts with a pulse ring for determining at least one of an angular position and a rotating direction of a wheel carrying the wheel force measuring assembly.

44. Wheel force measuring hub assembly according to claim 43, wherein a transmitting device is provided which transmits data obtained by the strain gauges to a vehicle-fixed part.

48. Wheel force measuring hub assembly according to claim 1, wherein at least one Hall sensor is provided which interacts with a pulse ring for determining at least one of an angular position and a rotating direction of a wheel carrying the wheel force measuring assembly.

49. Wheel force measuring hub assembly according to claim 48, wherein the pulse ring is ferromagnetic.

50. Wheel force measuring hub assembly according to claim 48, wherein the pulse ring has an encoding for determining a 0°

angle of the measuring hub assembly.

51. Wheel force measuring hub assembly according to claim 48, wherein the pulse ring is fixed to the exterior ring part.

52. Wheel force measuring hub assembly according to claim 48, wherein two Hall sensors are provided which are angularly offset with respect to one another for permitting a wheel rotating direction sensing.

53. Wheel force measuring hub assembly according to claim 51, wherein two Hall sensors are provided which are angularly offset with respect to one another for permitting a wheel rotating direction sensing.

45. In a wheel force measuring hub assembly including an exterior ring part adapted to be mounted at a wheel rim, an interior ring part adapted to be mounted at a vehicle axle, and a plurality of radially extending measuring webs connecting the exterior ring part and the interior ring part, the improvement consisting of strain gauges arranged on the measuring webs in a configuration such that wheel forces F_x, F_y and F_z and torques M_x, M_y and M_z are determined exclusively via shearing strains acting on said strain gauges to decouple individual force and torque components from one another.

46. Wheel force measuring hub assembly, comprising:

an exterior ring part adapted to be mounted at a wheel rim;

an interior ring part adapted to be mounted at a vehicle axle;

a plurality of radially extending measuring webs connecting the exterior ring part and the interior ring part;

strain gauges arranged on the measuring webs for determining forces and torques to be measured; and

wherein said strain gauges are arranged, aligned and connected with one another such that the forces and torques F_x, F_y, F_z and M_x, M_y, M_z are determined exclusively via shearing strains acting on said strain gauges to decouple individual forge and torque components from one another.

47. A wheel force indicator, comprising:

a measuring assembly including an exterior ring part, an interior ring part, and a plurality of radially extending measuring webs connecting the exterior and interior ring parts;

a wheel rim arranged on the exterior ring part of the measuring assembly;

a wheel flange arranged on the interior ring part of the measuring assembly; and

strain gauges arranged on the radially extending measuring webs for determining forces and torques to be measured, wherein said strain gauges are aligned and connected with one another such that the forces and torques are determined exclusively via shearing strains which occur during loading of the wheel force indicator to decouple individual force and torque components from one another.