Wheel speed sensor and interface systems and methods

• US 9,076,272 B2
• Filed: 05/28/2013
• Issued: 07/07/2015
• Est. Priority Date: 05/28/2013
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Hammerschmidt, Dirk
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): Lee, Tyler J
• Application Number:
  US13/903,088
• Publication Number:
  US 20140358320A1
• Time in Patent Office: 770 Days
• Field of Search: 701/1, 701/36, 701/48, 701/70, 701/71, 701/72, 701/74, 701/82, 701/90, 701/93, 701/30.8, 701/30.9, 701/31.1, 702/1, 702 33- 36, 702/47, 702/96, 702/98, 702/99, 702/104, 702/138, 702/142, 702/145, 702/148, 702/173, 731/150.1, 731/150.7, 731/150.8, 73121-132, 731/46, 731/462, 731/464, 731/465, 734/88, 734/94, 324/200, 324/207.13, 324/260, 303/121, 303/122.03, 303/122.06, 303/132, 303/138, 303/147, 303/177, 303/198, 340/444, 340/453
• US Class Current: 1/1
• CPC Class Codes: B60T 2250/06 Sensor zero-point adjustment; Offset compensation
• CPC Class Codes: B60T 8/00 Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force by changing number of effective brake cylinders in power brake systems B60T17/10
• CPC Class Codes: B60T 8/171 Detecting parameters used in the regulation; Measuring values used in the regulation
• CPC Class Codes: G01M 17/013 Wheels
• CPC Class Codes: G01M 17/02 Tyres
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 3/00 Measuring linear or angular speed; Measuring differences of linear or angular speeds G01P5/00 - G01P11/00 take precedence; direction and speed indication G01P13/045; counting mechanisms G06M
• CPC Class Codes: G01P 3/44 for measuring angular speed G01P3/56 takes precedence
• CPC Class Codes: G01P 3/443 mounted in bearings bearings F16C
• CPC Class Codes: G01P 3/487 delivered by rotating magnets
• CPC Class Codes: G01P 3/488 delivered by variable reluctance detectors
• CPC Class Codes: G01P 3/489 Digital circuits therefor
• CPC Class Codes: G07C 5/00 Registering or indicating the working of vehicles

Abstract

A measurement system includes a speed plus sensor and a control unit. The speed plus sensor is configured to detect a magnetic field in response to speed and resonance characteristics. The speed plus sensor is also configured to generate a sensor output signal having speed data and enhanced resonance data. The control unit is configured to receive the sensor output signal.

Claims

1. A measurement system comprising:

a speed plus sensor comprising a magnetic field sensor configured to detect a magnetic field in response to speed and resonance characteristics and generate a field sensor output;

a comparator component configured to receive the field sensor output and generate a comparator output by comparing the field sensor output with a threshold;

a speed measurement component configured to receive the field sensor output and generate a speed measurement signal having information relating to speed, based on frequency information from the field sensor output;

a summation component configured to add the speed measurement signal to the comparator output and generate a sensor output signal, amplitude shifted with respect to the speed measurement signal, wherein the sensor output signal comprises speed data and enhanced resonance data.

2. The system of claim 1, wherein the magnetic field is generated in response to a wheel rotation that is influenced by tire vibrations.

3. The system of claim 1, wherein the magnetic field sensor includes a magnetic pole wheel and is configured to generate the magnetic field in response to rotation and vibration of a tire.

4. The system of claim 1, wherein the resonance characteristics include at least one mode of vibration that influences a rotational speed of a wheel.

5. The system of claim 1, therein the speed plus sensor includes an interface configured to generate the output signal according to a protocol.

6. The system of claim 5, wherein the protocol includes first and second current levels, and wherein the sensor output signal is generated within the first and second current levels.

7. The system of claim 1, wherein the sensor output signal is an analog signal.

8. The system of claim 1, wherein the sensor output signal includes digital and analog components.

9. The system of claim 1, wherein the sensor output signal includes at least three levels.

10. A measurement system comprising:

a magnetic field sensor configured to measure a magnetic field and generate a field sensor output;

a summation component configured to combine an offset derived from the field sensor output, with the field sensor output to provide a modified sensor output; and

a current modulation component configured to generate a sensor output signal from the modified sensor output, the sensor output signal having speed data and enhanced resonance data.

11. The system of claim 10, wherein the current modulation component is configured to generate the sensor output signal according to a protocol having a lower level and an upper level.

12. The system of claim 10, further comprising an amplifier configured to scale the field sensor output according to a gain factor.

13. The system of claim 12, further comprising a gain adjustment component configured to generate the gain factor from the modified sensor output.

14. The system of claim 10, further comprising an analog to digital converter configured to convert the modified sensor output into a digital sensor output.

15. The system of claim 14, wherein the current modulation component is configured to utilize the digital sensor output to generate the sensor output signal.

16. The system of claim 14, further comprising an offset adjustment component configured to generate the offset from the digital sensor output.

17. The system of claim 10, further comprising a speed measurement component configured to generate an analog speed measurement signal from the modified sensor output.