Method and arrangement for synchronizing a segment counter with a fine position sensor

Patent metadata

Field	Value
Publication number	US-9631948-B2
Application number	US-201514828251-A
Country	US
Kind code	B2
Filing date	Aug 17, 2015
Priority date	Apr 15, 2012
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A method and an arrangement for performing the method for the error-free conversion of the counting values of a segment counter including Wiegand sensors and the position values of a fine position sensor into a total position value using the last magnetization direction of the Wiegand wire of a segment counter as part of the information for an absolute synchronization of counting and position values. The method further includes detecting a magnetization direction of the Wiegand wire on the basis of a combination of the magnetization direction, the last stored counting value of the segment counter, and information of the fine position sensor about the current.

First claim

The invention claimed is:

1. Method for an error-free conversion of the counting value of a segment counter and of the position value of a fine position sensor to a total position value, wherein said segment counter has at least one Wiegand sensor with a Wiegand wire and wherein the changes in position of a translational and/or rotational movement of an exciting magnet that is firmly coupled to a body to be monitored is detected by said segment counter, wherein a continuous segment counting value of said segment counter is stored in a memory, wherein by said fine position sensor a current segment position of said body to be monitored is detected,
wherein a magnetization direction of the Wiegand wire of the Wiegand sensor is detected wherein at a time Tx an examination is made on the basis of a combination of the magnetization direction, the last stored counting value of the segment counter, and
information of the fine position sensor about the current segment position, and then it is determined, based on the examination at time Tx, whether the counting value stored in the memory is used immediately or whether the counting value stored in the memory is incremented or decremented.

2. Method of claim 1 , wherein determining whether the counting value stored in the memory is used immediately or whether the counting value stored in the memory is incremented or decremented is based on correction information that is read out from a table coupled to the memory, wherein in said table for all movement sequences a respective correction information is stored, wherein said respective correction information is based on Wiegand sensor signals and associated counting signals, the magnetization direction of the Wiegand wire and the last counter reading.

3. Method of claim 2 , wherein the magnetization direction of the Wiegand wire is determined, at least in part, by a defined current that is supplied to an inductor coil, which surrounds the Wiegand wire, to determine whether magnets of the Wiegand wire are caused to flip and wherein a response signal, irrespective of the presence of a triggering pulse, is input to evaluation electronics for further processing.

4. Method of claim 3 , wherein the Wiegand sensor has a first and a second inductor coil wound around the Wiegand wire of said Wiegand sensor, wherein the current is supplied to said first inductor coil and the response signal is measured in said second inductor coil.

5. Method of claim 3 , wherein said Wiegand sensor comprises a single inductor coil wound around the Wiegand wire of said Wiegand sensor, wherein said single inductor coil is used for supplying current and generating the response signal.

6. Method of claim 4 , wherein the current supplied to said inductor coil is supplied in increasing or decreasing ramps.

7. Method of claim 1 , wherein said magnetization direction of said Wiegand wire is measured by at least one magnetic field sensitive sensor.

8. Method of claim 7 , wherein a Hall probe or a GMR sensor is used as said magnetic field sensitive sensor.

9. A method of error-free conversion of a counting value and of a position value to a total position value, the method comprising:
coupling an exciting magnet to a body to be monitored;
providing a Wiegand sensor with a Wiegand wire within proximity to the exciting magnet such that translational and/or rotational movements of the exciting magnet are sensed by the Wiegand wire;
storing a continuous segment counting value in memory, wherein the continuous segment counting value stored in memory corresponds to a counting value made by a segment counter with the Wiegand sensor;
detecting a current segment position of the body with a fine position sensor;
detecting a magnetization direction of the Wiegand wire;
examining, at a time Tx, a combination of the following: (i) the magnetization direction; (ii) a last stored counting value of the segment counter; and (iii) information of the fine position sensor about current segment position; and
determining, based on the examination at the time Tx, whether the counting value stored in memory is used immediately or whether the counting value stored in memory is incremented or decremented.

10. The method of claim 9 , wherein determining whether the counting value stored in the memory is used immediately or whether the counting value stored in memory is incremented or decremented is based on correction information that is read out from a table coupled to the memory.

11. The method of claim 10 , wherein movement sequences for a respective correction information are also stored in the table and wherein the respective correction information is based on signals from the Wiegand sensor and associated counting signals as well as the magnetization direction of the Wiegand wire and the last counter reading.

12. The method of claim 11 , wherein the magnetization direction of the Wiegand wire is determined, at least in part, by a defined current that is supplied to an inductor coil that surrounds the Wiegand wire.

13. The method of claim 12 , wherein the defined current determines whether elementary magnets of the Wiegand wire are caused to flip and wherein a response signals, irrespective of a presence of a triggering pulse, is input to evaluation electronics for further processing.

14. The method of claim 13 , wherein the Wiegand sensor has a first and second inductor coil wound around the Wiegand wire of the Wiegand sensor.

15. The method of claim 14 , wherein the current is supplied to the first inductor coil and the response signal is measured in the second inductor coil.

16. The method of claim 13 , wherein the Wiegand sensor comprises a single inductor coil wound around the Wiegand Wire of the Wiegand sensor.

17. The method of claim 16 , wherein the single inductor coil is used for supplying current and generating the response signal.

18. The method of claim 17 , wherein the current supplied to the inductor coil is supplied in increasing or decreasing ramps.

19. The method of claim 9 , wherein the magnetization direction of the Wiegand wire is measured by at least one magnetic field sensitive sensor.

20. The method of claim 19 , wherein the at least one magnetic field sensitive sensor comprises a Hall probe or a GMR sensor.

Assignees

• Avago Technologies General Ip

Inventors

• Mehnert Walter
• Theil Thomas

Classifications

• G01D5/2046

  by a movable ferromagnetic element, e.g. a core · CPC title

• G01D5/145 Primary

  influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06) · CPC title