• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:

    公开号:AT510377A1
    申请号:T0152310
    申请日:2010-09-14
    公开日:2012-03-15
    发明作者:Josef Janisch
    申请人:Zentr Mikroelekt Dresden Gmbh；
    IPC主号:
    专利说明:

    invention Disclosure
    The invention describes a method and embodiments for the absolute position determination by means of two Hall sensors. With this invention, both the absolute angular position of a rotatable body, as well as the absolute displacement position of a translationally moving element can be determined, wherein the two signals of the Hall sensors can have a wide range of arbitrary phase offset and signal swing.
    The contactless determination of the absolute rotational angle or linear position of a moving body is needed because of its robustness and durability, especially in sensors of the automotive industry, industrial automation, medical devices and the consumer goods industry.
    State of the art
    The non-contact detection of the absolute rotation angle by means of a rotatably mounted magnet and an evaluation circuit based on Hall sensors is described in various patents.
    DE 698 16 755 T2 (2004.06.03) describes a method which determines the signals required for the calculation of the rotational position from the difference formation of two Hall sensor groups. A disadvantage of this method is that at least three sensors are required and the device described requires an axial structure in which the Hall sensors are located below the rotatably mounted magnet.
    In a further known embodiment, WO 02009088767A2 describes a method which generates the absolute angle information by analog signal processing from two phase-shifted signals.
    A disadvantage of this method is that the purely analog signal processing requires very precise analog circuits as well as multiple accurate offset and gain trims.
    Technical task
    The object of the invention is to describe a sensor system based on Hall sensors, which has the abovementioned
    Josef Janisch did not have disadvantages, in particular it should be possible with the sensor system to detect the rotational position over a full rotation of 360 ° absolute and to allow mounting both below and also laterally of the rotatable magnetic field source.
    Furthermore, the desired solution should make it possible to integrate both the sensors and the evaluation circuit on a substrate and to produce them inexpensively, ie on the smallest possible surface, using standard process methods of the semiconductor industry.
    Inventive solution
    This is achieved according to the invention by the characterizing features of claim 1 as a method and of claim 2 as a device. Further advantageous embodiments are proposed according to the subclaims.
    Description of the drawings
    The invention will now be further explained with reference to the embodiments and with reference to an embodiment which is shown schematically in the form of signal diagrams.
    Fig. 1 shows an embodiment as described in claim 2. The sensitive to the measurement of the magnetic axes of the Hall elements 1,2 are shown as arrows.
    Fig. 2 shows an embodiment as described in claim 4. The magnetic field source shown here is a 2-pole disc magnet 5 or ring magnet 8, which allows an absolute measurement of the rotational position over 360 °.
    Fig. 3 shows a plan view of the embodiment described in Fig. 1.
    Fig. 4 shows an embodiment as described in claim 5.
    Fig. 5 shows an embodiment as described in claim 7.
    Josef Janisch
    Fig. 6 and shows a plan view of the embodiment described in Fig. 2
    Fig. 7 corresponds to the structure of Fig. 2, but shows the integrated according to claim 7 solution of the sensor elements 1 and 2
    FIGS. 8-12 show various embodiments of suitable magnetic field sources:
    FIG. 8 and FIG. 9 show a 2-pole diametrically magnetized disk magnet 5 or ring magnet 8, with which a determination of the absolute rotational position over 360 ° is possible.
    FIG. 10 and FIG. 11 show a multi-pole magnetized disc magnet 7 or ring magnet 9 as described in claim 3. The illustrations shown here show an embodiment with 4 poles, the application of the invention is not limited to this number of poles, but applies to any number of pole pairs. The maximum absolutely measurable rotational position range in these embodiments is 360 ° / pp, where pp corresponds to the number of pole pairs of the magnets.
    Fig. 12 shows an embodiment as described in claim 6. In this embodiment, a multi-pole bar, strip or strip magnet 12 is used, thereby enabling the absolute position determination of a translationally moving body. The maximum absolutely measurable translatory travel range corresponds to the length of a pole pair.
    Fig. 13 is a block diagram of the signal processing. The analog signal processing path is shown in block 100, the digital signal processing path is shown in block 200. Analogously, in FIG. 14-17 the signal profile is traced by means of an example.
    In this example, a device according to one of the embodiments of FIG. 1 or FIG. 2 is traced. In the example of FIG. 14, it is assumed that the measured signals of the Hall sensors 1, 2 have a phase angle of 30 °, are already pre-amplified and due to influences of the positioning accuracy as well as due to procedural tolerances both
    Josef Janisch with offset voltages as well as with different signal levels are afflicted.
    In a first step, the offset voltage of the sensor signals 101, 102 is subtracted and the signal levels are adjusted to a normalized signal swing (for example 2VSS). The normalized signal levels are available as signal 107 and 108.
    In order to calculate the required trimming values for Offset 1, 0 ffset 2, Gain 1 and Gain 2, it is sufficient to determine the minimum and maximum values of the sensor signals 101, 102. This can, as described in claim 1, by simple rotation of the magnetic field source over a full period with simultaneous determination of the minimum and maximum values of the sensor signals 101 and 102 happen.
    From the minimum and maximum values, the values necessary for trimming can then be calculated as follows: TJ1, TT 1 Offietl = ma »^ -i " HO 4 -OO Offset * ma * min
    Gainl = normalized _ signal swing
    Gain2 = normalized _ signal swing HO _HO n ^ max n ^ min [1] [2] [3] Ml for Hlmax, min = maximum or minimum value of sensor signal 101 H2max, min = maximum or minimum value of sensor signal2 102
    Of these normalized signals, the sum 109 and the difference 110 are formed in the next step. In Fig. 16, these signals are shown.
    The ratio of the signal swing from the sum signal to the difference signal depends on the phase position φ of the input signals 101, 102. However, the phase position cp from the sum signal to the difference signal is always 90 °. An exception are the special cases of the phase positions φ = 360 ° = 0 ° and φ = 180 °, in which a determination of the rotational position is not possible because at φ = 180 ° the Summensig-
    Josef Janisch nal becomes 0 and at φ = 360 ° = 0 ° the difference signal becomes 0.
    In Fig. 18, this relation is shown graphically. The X-axis shows the phase relationship of the input signals and the Y-axis shows the amplitude ratio of the sum signal to the difference signal.
    In a further step, the sum signal 109 and the difference signal 110 are in turn normalized to a predetermined value (for example 2VSS).
    In order to calculate the required trim values for Gain3 and Gain4 it is sufficient to determine the minimum and maximum values of the sum and difference signal. This can, as described in claim 1, by simple rotation of the magnetic field source 5 over a full period with simultaneous determination of the minimum and maximum values of sum and difference signal · happen.
    From the minimum and maximum values, the values necessary for trimming can then be calculated as follows: ". "Normalized signal swing
    Gain2 = - [5]
    Sum signal sum signal _,. normalized signal swing
    Yarn 4 = - = - 2- [6]
    Difference signal ^ - difference signal
    Assuming that the normalized sensor signals 107, 108 no longer have an offset voltage, no further offset is produced by the sum and difference formation. This can likewise be checked by means of the minimum and maximum values of the sum and difference signal and if necessary also corrected:
    Offset.
    sum signal
    Sum signal + Sumrnensignalmin '2 [7]
    offset
    DiJJerenzsignat
    Difference signal + difference signal signal mjn 2 [8]
    Josef Janisch
    The normalized signals of the sum signal 113 and the difference signal 114 thus yield two signals phase-shifted by exactly 90 ° with the same signal swing. These signals are now used directly to calculate the rotational position.
    Subsequently, the normalized sum signal 113 with Vsin and the normalized difference signal 114 with Vcos are described.
    Vsin = Gain3 * [Gainl * (Hl-Offsetl) + Gain2 * (H2-Offset2)] [9] Vcos = Gain4 * [Gainl * (Hl-Offsetl) -Gain2 * (H2 - Offset2)] [10] For Hl H2 Offset1 Of fset2 Gain1 Gain2 Gain3 Gain4 = Sensor signal from Hall sensor 101 = Sensor signal from Hall sensor2 102 = Offset signal from Hall sensor 103 = Offset signal from Hall sensor2 104 = Gain of sensor signal Hl 105 = Gain of sensor signal H2 106 = Gain of sum signal 111 = Gain of difference signal 112
    Starting from the input signals Vsin 113 and Vcos 114, the absolute rotational position W 202 of the magnetic field source can be determined using the arctangent function W = arctan ^ Sm [11] V cos or other suitable means of coordinate transformation, such as a digital CORDIC algorithm.
    The absolute value B 203 of the coordinate transformation is constant for all tumor positions and amounts to: B = vVsin2 + Kcos3 = const. [12]
    In many applications, it may be useful to bring the calculated rotational position with a defined mechanical position of the rotatable member 4 in line, for example, the zero position of a turntable. To facilitate this, an arbitrary rotational position can be set to zero by subtracting a zero reference value 204.
    Furthermore, the achieved accuracy of the displayed rotational position can optionally be increased by a linearization circuit 205
    Josef Janisch. Typical forms of linearization are tables or mathematical correction functions which try to match the calculated rotational position to reference points defined by the user.
    Subsequently, the calculated and linearized rotational position W_L can be made available to the user by conversion into an analog signal form 207 or a digital signal form 208
    In an advantageous embodiment, as described in claim 8, the signal processing can be performed digitally. The signals 101, 102 generated by the Hall sensors 1, 2 are converted directly into a digital signal form by means of an analog-to-digital converter, and the signal processing steps described in FIG. 13, block 100 are carried out in a digital arithmetic unit. The necessary parameters for gain, offset, zero point and linearization can be stored in a digital memory.
    As an example, FIG. 14 shows two input signals 101, 102, which are phase-shifted by 30 ° and have different offset and level hoppers
    Fig. 15 shows the input signals after correction of the offset values and normalization of the signal levels 107, 108.
    FIG. 16 shows the sum signal 109 and the difference signal 110 of the normalized signal levels 107, 108.
    Fig. 17 shows the normalized sum signal 113 113 = Vsin and the normalized difference signal 114 = V cos.
    Furthermore, in a second ordinate axis, the absolute rotational position 202 calculated from Vsin and Vcos is represented in a scaling of +/- 180 °.
    FIG. 18 shows the ratio of the signal strokes from the sum signal to the difference signal at different phase positions cp of the input signals.
    Josef Janisch
    权利要求:
    Claims (8)
    [1]
    Claim 1: Method for determining the absolute position of a rotatably mounted element (4) and a translationally moving element (10) to which a magnetic field source is attached whose magnetic properties by means of two signals generated by fixed Hall sensors (1,2) one Phase offset 0 in the range of 0 ° &lt; 0 <180 ° or 180 ° &lt; 0 <360 ° can be determined, which are used to determine the absolute position determination, characterized in that the influence of the positioning accuracy of the Hall sensors (1,2) relative to the Magnetfeldqueile (5) on the accuracy of the determination of the absolute position the amplitude ratios and the offset values of the sensor signals are determined and normalized from the minimum and maximum values of the signals (101, 102) generated by the Hall sensors (107, 108), the determination of the minimum and maximum values being effected simply by rotation of the rotatable element (4). or displacement of the translationally moving element (10) and the magnetic field source attached thereto over a full period with simultaneous measurement of the signals (101,102) of both Hall sensors (1,2) can be carried out, and that by two independent of the phase offset of the sensor signals (101,202) to each other exactly 90 ° out of phase signals (109,110) which for Bes absolute position are required, the sum (109) and the difference (110) are formed by the normalized sensor signals (107, 108) and these signals are in turn normalized after determination of the amplitude ratio (113, 114), whereby the determination of the minimum and maximum values simply by rotation of the rotatable element (4) or displacement of the translationally moving element (10) and the attached magnetic field source over a full period with simultaneous measurement of the sum signal (109) and the difference signal (110) and evaluation of the minimum and maximum values both signals (109,110) can take place.
    [2]
    Claim 2: A device for non-contact detection of the absolute position of an element (4) over an angular range of 360 ° by means of the method of claim 1, wherein the pre-Josef Janisch direction on the rotatable member (4) attached as a 2-pole diametrically Magnetized disc magnet (5) or 2-pole diametrically magnetized ring magnet (8) running magnetic field source, characterized in that two lying in a plane, but spatially offset in the direction of rotation laterally of the magnetic field source (5) arranged Hall sensors (1,2) the detect radial component of the magnetic field, wherein the distance between the magnetic field source (5) and Hall sensors (1,2) is suitably chosen so that a sufficient signal amplitude for the further processing of the signals (101,102) can be achieved.
    [3]
    Claim 3: Device for non-contact detection of the absolute rotation pitch of an element (4) over an angular range of <360 ° by means of the method according to claim 1, wherein the device comprises a disk magnet (7) magnetized on the rotatable element (4) or multipole magnetized ring magnet (9) having pp pole pairs running magnetic field source, which allows a measurable absolute rotational position range of 360 ° divided by the number of pole pairs, characterized in that two lying in a plane, but spatially offset in the direction of rotation laterally of Magnetic source (5) arranged Hall sensors (1,2) detect the radial component of the magnetic field, on the one hand, the distance between the Hall sensors (1,2) is chosen so that the resulting phase offset of the sensor signals is not 180 ° and not 360 ° on the other hand the distance between magnetic field source (5) and Hall sensors (1,2) zweckmäßiqerweise is chosen so that a sufficient for the further processing of the signals (101,102) signal amplitude can be achieved.
    [4]
    Claim 4: Device according to Claim 2 or Claim 3, characterized in that two Hall sensors (1, 2) located in a plane but spatially offset in the direction of the rotational movement below the magnetic field source (5) detect the vertical component of the magnetic field, on the one hand the distance between the Hall sensors (1,2) and the distance of the Hall sensors (1,2) from the axis of rotation (3) is chosen so that the resulting phase offset of the sensor signals not 180 ° and not Josef Janisch 360 ° On the other hand, the distance between the magnetic field source (5) and Hall sensors (1,2) is expediently chosen so that a sufficiently large signal amplitude can be achieved for the further processing of the signals (101, 102).
    [5]
    Claim 5: Apparatus according to claim 2 or claim 3, characterized in that the Hall sensors (1,2} are not on a plane, but are tilted inwards or outwards in the direction of the axis of rotation.
    [6]
    Claim 6: A device for contactless detection of the position of an element (10), by means of the method according to claim 1, wherein the device comprises a multi-pole magnetic field source (12) mounted on the displaceable element (10) along a translatory axis (11) allows a measurable absolute travel range of the length of a pole pair, characterized in that two in one plane, but spatially offset in the direction of the displacement movement below the magnetic field source (12) arranged Hall sensors (1,2) detect the vertical component of the magnetic field, on the one hand the distance between the Hall sensors (1,2) is chosen such that the resulting phase offset of the sensor signals is not 180 ° and not 360 ° and on the other hand the distance between magnetic field source (12) and Hall sensors (1,2) is suitably chosen so that for the further processing of the signals (101,102) sufficiently large Signala mplitude can be achieved.
    [7]
    Claim 7: Apparatus according to claim 2 - claim 4, and claim 6, characterized in that the Hall sensors (1,2) are integrated together on a sensor chip, which additionally also the evaluation electronics, which include both analog components 100 and digital components 200 can.
    [8]
    Claim 8: Apparatus according to claim 7, characterized in that the settings of offset (103,104) and gain (105,106,111,112) after conversion of the analog input signals (101,102) by means of an analog-to-digital converter into digital form in a computer unit takes place by digital means. Josef Janisch
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    法律状态:
    2018-10-15| PC| Change of the owner|Owner name: IDT EUROPE GMBH, DE Effective date: 20180903 |
    2021-05-15| MM01| Lapse because of not paying annual fees|Effective date: 20200914 |
    优先权:
    申请号 | 申请日 | 专利标题
    ATA1523/2010A|AT510377B1|2010-09-14|2010-09-14|METHOD AND EMBODIMENTS FOR THE ABSOLUTE POSITION DETERMINATION BY MEANS OF TWO HALL SENSORS|ATA1523/2010A| AT510377B1|2010-09-14|2010-09-14|METHOD AND EMBODIMENTS FOR THE ABSOLUTE POSITION DETERMINATION BY MEANS OF TWO HALL SENSORS|
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