Angle of rotation sensor having a counting arrangement with at least two pulser-wire motion sensors providing electrical energy used as a voltage supply

• US 6,084,400 A
• Filed: 04/30/1997
• Issued: 07/04/2000
• Est. Priority Date: 03/07/1994
• Status: Expired due to Term

• Current Assignee: AMB GmbH
• Original Assignee: AMB GmbH
• Inventors: Wirth, Peter, Steinich, Klaus-Manfred
• Primary Examiner(s): Snow, Walter E.
• Application Number:
  US08/716,225
• Time in Patent Office: 1,161 Days
• Field of Search: 324/207.14, 324/207.13, 324/207.23, 324/207.24, 324/207.25, 324/235, 324/173, 324/174, 307/65, 307/66
• US Class Current: 324/207.13
• CPC Class Codes: G01D 2205/26 Details of encoders or position sensors specially adapted to detect rotation beyond a full turn of 360°, e.g. multi-rotation
• CPC Class Codes: G01D 5/2451 Incremental encoders G01D5/2454 takes precedence
• CPC Class Codes: G01P 3/4815 using a pulse wire sensor, e.g. Wiegand wire
• CPC Class Codes: G01P 3/487 delivered by rotating magnets

Abstract

An angle of rotation sensor for measuring the angular position of a rotary shaft during more than one revolution consists of a fine angle of rotation sensor linked to the rotary shaft and of a counter. The revolutions of the shaft are all counted without mechanical gears, without an outer voltage supply and without supply batteries, with a simple and economical design. Pulse wire movement sensors supply voltage pulses depending on the rotation of the shaft. The number of voltage pulses is stored in a non-volatile read/write memory.

Claims

1. Angle of rotation sensor (1) for measurement of the angular position of a rotary shaft (2) over more than one revolution, including a fine angle of rotation sensor (3) attached to the rotary shaft which measures the absolute angular position of the rotary shaft over one revolution, and a counting arrangement (4) to count the total number of revolutions of the rotary shaft, wherein the counting arrangement (4) comprises at least two pulse-wire motion sensors (70, 71) fixed on an arc-segment, at least one permanent magnet (72), a nonvolatile read/write memory (21) and an electronic counter circuit (13);

wherein a part of the electrical energy provided by the pulse-wire motion sensor (13) is used as a voltage supply;

wherein each pulse-wire motion sensor is connected to a pulse forming circuit (16), comprising a charging element (24) which is supplied with voltage pulses from the motion sensors via a switching element (23), and a further switching element (27) through which the voltage of the charging element is passed to an auxiliary voltage supply (34).

2. Angle of rotation sensor according to claim 1, wherein the switching elements (23, 27) are semiconductor diodes and wherein the charging element is a capacitor.

3. Angle of rotation sensor according to claim 1, wherein the pulse forming circuit comprises a discharging resistor (25) and an electronic switch (26) in series which is supplied with voltage from the charging element (24).

5. Angle of rotation sensor according claim 1, wherein the non-volatile read/write memory 21 is a static semiconductor memory, supplied with voltage from a voltage energy store.

6. Angle of rotation sensor according to claim 1, wherein three unipolar pulse-wire motion sensors (6, 7, 8), a switching permanent magnet (10) attached to the rotary shaft (2) and two reset permanent magnets (11, 12) attached to the rotary shaft are used.

7. Angle of rotation sensor according to claim 1, wherein two bipolar pulse-wire motion sensors (70, 71), and at least one permanent magnet (72) attached to the rotary shaft (2) are used.

8. Angle of rotation sensor according to claim 1, wherein three unipolar pulse-wire motion sensors, six fixed permanent magnets and two ferromagnetic pole pieces attached to the rotary shaft (2) are used.

9. Angle of rotation sensor according to claim 1, wherein three bipolar pulse-wire motion sensors, six fixed permanent magnets and one ferromagnetic pole piece attached to the rotary shaft (2) are used.

10. Angle of rotation sensor according to claim 1, wherein one pulse-wire segment is attached to the rotary shaft (2), two fixed positioned sensing coils and four fixed positioned permanent magnets are used.

4. Angle of rotation sensor (1) for measurement of the angular position of a rotary shaft (2) over more than one revolution, including a fine angle of rotation sensor (3) attached to the rotary shaft which measures the absolute angular position of the rotary shaft over one revolution, and a counting arrangement (4) to count the total number of revolutions of the rotary shaft, wherein the counting arrangement (4) comprises at least two pulse-wire motion sensors (70, 71) fixed on an arc-segment, at least one permanent magnet (72), a nonvolatile read/write memory (21) and an electronic counter circuit (13);

wherein a part of the electrical energy provided by the pulse-wire motion sensor (13) is used as a voltage supply;

wherein the storage element of the non-volatile read/write memory 21 is realized in ferroelectric technology as a crystal dipole, whose switching state is changed by application of an electric field.