Non-contact system for detecting an angle of rotation
First Claim
1. An arrangement for contactless determination of an absolute angular position of a rotatable element between 0°
- and 360°
, said arrangement comprisingmeans for generating a magnetic field comprising at least one magnetic field-producing element arranged to rotate with said rotatable element;
a magnetic field sensor stationary in relation to said rotatable element and arranged to detect said magnetic field, said magnetic field sensor including a first sensor element (IC1) and a second sensor element (IC2), wherein said first sensor element operates according to a magnetoresistive effect so as to generate a first output signal linearly dependent on an angle between said magnetic field and said magnetic field sensor, whereby said first output signal has respective values when said angle is between 0° and
180°
that repeat when said angle is between 180° and
360°
, said second sensor element operates according to a Hall effect to generate a second output signal which has a high value when said angle is between 0° and
180° and
a low value when said angle is between 180° and
360°
; and
an evaluation circuit (A) comprising means for evaluating said first output signal and said second output signal in order to determine said absolute angular position of said rotatable element between 0° and
360°
.
1 Assignment
0 Petitions
Accused Products
Abstract
The arrangement for contactless determination of an angular position of a rotatable element, such as a camshaft of an internal combustion engine, which includes a magnet arranged to rotate with the rotatable element; a magnetic field sensor stationary in relation to the rotatable element and including a first sensor element (IC1) and a second sensor element (IC2), wherein the first sensor element generates a first output signal linearly dependent on an angle between the magnetic field and the magnetic field sensor according to a magnetoresistive effect, whereby the first output signal has respective values between 0° and 180° that repeat between 180° and 360°, and the second sensor element generates a second output signal having a high value between 0° and 180° and a low value between 180° and 360° according to a Hall effect; and an evaluation circuit (A) for analyzing output signals of both sensor elements to determine the angular position of the rotatable element between 0° and 360°. The evaluating circuit finds that the absolute angular position is either of two angular orientations spaced 180° from each other only from the signal from the first sensor element and selects one of them as the absolute angular position according to the second output signal.
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Citations
7 Claims
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1. An arrangement for contactless determination of an absolute angular position of a rotatable element between 0°
- and 360°
, said arrangement comprisingmeans for generating a magnetic field comprising at least one magnetic field-producing element arranged to rotate with said rotatable element;
a magnetic field sensor stationary in relation to said rotatable element and arranged to detect said magnetic field, said magnetic field sensor including a first sensor element (IC1) and a second sensor element (IC2), wherein said first sensor element operates according to a magnetoresistive effect so as to generate a first output signal linearly dependent on an angle between said magnetic field and said magnetic field sensor, whereby said first output signal has respective values when said angle is between 0° and
180°
that repeat when said angle is between 180° and
360°
, said second sensor element operates according to a Hall effect to generate a second output signal which has a high value when said angle is between 0° and
180° and
a low value when said angle is between 180° and
360°
; and
an evaluation circuit (A) comprising means for evaluating said first output signal and said second output signal in order to determine said absolute angular position of said rotatable element between 0° and
360°
.- View Dependent Claims (2, 3, 4, 5, 6)
- and 360°
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7. An arrangement for contactless determination of an absolute angular position of a rotatable element between 0°
- and 360°
, said arrangement comprisingmeans for generating a magnetic field comprising at least one magnetic field-producing element arranged to rotate with said rotatable element;
a magnetic field sensor stationary in relation to said rotatable element and arranged to detect said magnetic field, said magnetic field sensor including a first sensor element (IC1) and a second sensor element (IC2), wherein said first sensor element operates according to a magnetoresistive effect so as to generate a first output signal linearly dependent on an angle between said magnetic field and said magnetic field sensor, whereby said first output signal has respective values when said angle is between 0° and
180°
that repeat when said angle is between 180° and
360°
, said second sensor element operates according to a Hall effect to generate a second output signal which has a high value when said angle is between 0° and
180° and
a low value when said angle is between 180° and
360°
; and
an evaluation circuit (A) comprising means for evaluating said first output signal and said second output signal in order to determine said absolute angular position of said rotatable element between 0° and
360°
, wherein said means for evaluating includes means for determining two angular orientations spaced 180°
from each other from only said first output signal of said first sensor element and means for selecting one of said two angular orientations as said absolute angular position of said rotatable element according to said second output signal of said second sensor element.
- and 360°
Specification