WO2019185095A1 - Arrangement for measuring a force or a torque on a machine element and method for testing the arrangement - Google Patents

Arrangement for measuring a force or a torque on a machine element and method for testing the arrangement Download PDF

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Publication number
WO2019185095A1
WO2019185095A1 PCT/DE2019/100292 DE2019100292W WO2019185095A1 WO 2019185095 A1 WO2019185095 A1 WO 2019185095A1 DE 2019100292 W DE2019100292 W DE 2019100292W WO 2019185095 A1 WO2019185095 A1 WO 2019185095A1
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Prior art keywords
magnetic field
field sensors
force
magnetization
axis
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PCT/DE2019/100292
Other languages
German (de)
French (fr)
Inventor
Stephan Neuschaefer-Rube
Thomas Lindenmayr
Jan Matysik
Original Assignee
Schaeffler Technologies AG & Co. KG
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Priority to DE102018107570.7A priority Critical patent/DE102018107570B4/en
Priority to DE102018107570.7 priority
Application filed by Schaeffler Technologies AG & Co. KG filed Critical Schaeffler Technologies AG & Co. KG
Publication of WO2019185095A1 publication Critical patent/WO2019185095A1/en

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L3/00Measuring torque, work, mechanical power, or mechanical efficiency in general
    • G01L3/02Rotary-transmission dynamometers
    • G01L3/04Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft
    • G01L3/10Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electrical or magnetic means for indicating
    • G01L3/101Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electrical or magnetic means for indicating involving magnetic or electromagnetic means
    • G01L3/102Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electrical or magnetic means for indicating involving magnetic or electromagnetic means involving magnetostictive means
    • G01L3/103Details about the magnetic material used
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L25/00Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
    • G01L25/003Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency for measuring torque

Abstract

The invention relates to a method for testing an arrangement for measuring a force and/or a torque (Mt) on a machine element (01) extending in an axis (03), wherein the measurement is carried out using the inverse-magnetostrictive effect. The machine element (01) has at least two magnetization regions (04) which extend circumferentially around the axis (03). The arrangement comprises at least four magnetic field sensors (06) for measuring an axial component of a magnetic field caused by the magnetization and by the force and/or by the torque (Mt). There are at least two combinations of at least two of the magnetic field sensors (06) in each case which are each sufficient to measure the force or the torque (Mt). In one step of the method, a first measured value of the force or of the torque (Mt) is determined with a first one of the combinations of the magnetic field sensors (06). A second measured value of the force or of the torque (Mt) is also determined with a second one of the combinations of the magnetic field sensors (06). According to the invention, the first measured value and the second measured value are compared, as a result of which a malfunction of the arrangement can be detected. The invention further relates to an arrangement for measuring a force and/or a torque (Mt) on a machine element (01).

Description

 Arrangement for measuring a force or a moment on a machine element and method for checking the arrangement

The present invention initially relates to a method for testing an arrangement for measuring a force and / or a moment on a machine element extending in an axis, wherein the measurement of the force or the moment takes place using the inverse magnetostrictive effect. The machine element has at least two circumferentially extending around the axis

Magnetization areas, which form a primary sensor for the measurement. The arrangement comprises at least four magnetic field sensors as secondary sensors. The method allows the detection of a malfunction of the arrangement. In addition, the invention relates to an arrangement for measuring a force and / or a

Moment on a machine element.

US 6,490,934 B2 teaches a magnetoelastic torque sensor for

Measuring a torque, which points to an element with a

ferromagnetic, magnetostrictive and magnetoelastically active region acts. This area is formed in a transducer, which sits as a cylindrical sleeve, for example on a shaft. The torque sensor faces the transducer.

From EP 0 803 053 B1 a torque sensor is known, which has a

magnetoelastic transducer comprises. The transducer sits as a cylindrical sleeve on a shaft.

US 8,893,562 B2 shows a method for detecting a magnetic

Noise in a magnetoelastic torque sensor. Of the

Torque sensor includes a torque converter with opposite

polarized magnetizations and multiple magnetic field sensors, between which can be switched.

US 8,578,794 B2 teaches a magnetoelastic torque sensor having a longitudinally extending member and a plurality of magnetoelastically active ones Regions as well as with primary and secondary magnetic field sensors, which are axially spaced.

From US 2014/0360285 A1 there is known a magnetoelastic torque sensor comprising a hollow longitudinally extending member having a plurality of magnetoelastically active regions. The hollow element contains primary and secondary magnetic field sensors.

From US 8,087,304 B2 a magnetoelastic torque sensor is known, which comprises a longitudinally extending element with a plurality of magnetoelastically active regions. The torque sensor includes primary and secondary magnetic field sensors connected as a Wheatstone bridge.

US 2004/0154412 A1 shows a sensor for measuring divergent

Magnetic fields, which emerge from a magnetoelastic wave. The shaft has two magnetization regions, each of which is assigned two coils for measuring the magnetic fields.

US 2014/0360285 A1 teaches a magnetoelastic torque sensor with which a torque acting on a hollow shaft can be measured. The hollow shaft has three circumferentially magnetized magnetization regions with alternating polarities. Opposite the magnetization regions four secondary magnetic field sensors are arranged.

From US Pat. No. 9,151,668 B2 a magnetoelastic torque sensor is known, which should have a reduced signal noise. The torque sensor comprises a hollow shaft having three circumferentially magnetized magnetization regions which have alternating polarities. Compared to the

Magnetization areas are arranged up to eight magnetic field sensors.

DE 10 2015 209 286 A1 shows an arrangement and a method for measuring a force and / or a moment on a machine element using the inverse-magnetostrictive effect. The machine element has at least one Magnetization area for a magnetization on. At least two spaced magnetic field sensors are used for measuring a magnetic field caused by the magnetization as well as by the force and / or by the moment.

According to the method, the measurement signals of the magnetic field sensors are processed individually.

The object of the present invention, starting from the prior art, is to be able to better recognize malfunctions in a measurement of forces and / or moments based on the inverse-magnetostrictive effect

For example, to be able to meet higher requirements in the field of functional safety.

Said object is achieved by a method according to the appended claim 1 and by an arrangement according to the appended independent claim 10.

The method according to the invention is used to test an arrangement which is used to measure a force and / or moment at an axis

extending machine element is formed. With the method, a correct function of the arrangement is monitored and a malfunction of the arrangement can be detected.

The force or the moment acts on the machine element of the arrangement, which leads to mechanical stresses and the machine element usually deforms slightly. The axis preferably forms an axis of rotation of the

Machine element. The following directions, namely the axial direction, the radial direction and the tangential direction are related to the said axis. The arrangement is preferably designed to measure a moment which lies in the axis, so that it is a

Torsionsmoment act, by which the machine element is loaded. The vector of the moment is in the axis. The machine element has at least two magnetization areas extending circumferentially around the axis for each magnetization formed in the machine element. It is thus at least two magnetization areas revolving around the axis, ie circular

Magnetization regions, wherein the axis itself preferably does not form part of the magnetization regions. The magnetization regions preferably have only a tangential orientation with respect to a surface of the machine element extending around the axis. The

Magnetization regions preferably each extend along one

closed path around the axis, the magnetization areas may have short gaps. The magnetization regions preferably have a same spatial extent and are axially spaced apart. Particularly preferably, the magnetization regions are designed in the form of magnetization tracks. The magnetization regions each form a primary sensor for determining the force or the moment.

The machine element preferably also has magnetically neutral regions, which are each arranged axially between the magnetization regions and / or axially next to the magnetization regions of the machine element. The

Machine element preferably has at least one of the magnetically neutral regions. The magnetically neutral regions have neither one

Permanent magnetization, nor is the arrangement designed to temporarily magnetize the magnetically neutral regions. The magnetically neutral regions are preferably not magnetized. The magnetically neutral regions are preferably each formed in an axial section of the machine element.

The arrangement furthermore comprises at least four magnetic field sensors which each form a secondary sensor for determining the force or the moment. The primary sensors, d. H. the magnetization areas are used to convert the force to be measured or the moment to be measured into a corresponding one

Magnetic field, while the secondary sensors allow the conversion of this magnetic field into electrical signals. The magnetic field sensors are each for individual measurement of an axially oriented direction component of a through Magnetization as well as caused by the force and / or by the moment

Magnetic field formed. The said magnetic field occurs due to

inverse magnetostrictive effect. Thus, the possible with the arrangement measurement based on the inverse magnetostrictive effect.

There are at least two different combinations of at least two of the magnetic field sensors, each of these combinations being sufficient to measure the force or torque. Thus, the at least two combinations are redundant with regard to their suitability for measuring the measurement of the same force or moment. The combinations are to be understood in the sense of combinatorics and each provide a selection of at least two of

Magnetic field sensors, wherein the combinations different numbers of the

Magnetic field sensors may include and one of the combinations may be formed by all of the magnetic field sensors. At least two different combinations of the at least four magnetic field sensors can be selected, each of which is suitable for measuring the force or the moment. Particularly preferably, there are at least three of the combinations of at least two of the magnetic field sensors, each of these combinations being sufficient for measuring the force or the moment.

The magnetic field sensors are arranged opposite the machine element, with preferably only a small radial distance between the magnetic field sensors and an inner or outer surface of the machine element being present. The magnetic field sensors preferably have an equal distance from the axis.

In one step of the method according to the invention, a determination of a first measured value of the force or of the moment takes place with a first of the combinations of the magnetic field sensors while the force or the moment is acting. The first

Measured value is taken from measurement signals of the individual to the first combination

belonging magnetic field sensors determined.

In a further step of the method according to the invention, a determination of a second measured value of the force or of the moment with a second of the Combinations of magnetic field sensors while the force or moment is working. The second measured value is taken from measurement signals of the individual to the second

Combination belonging magnetic field sensors determined.

The determination of the first measured value and the determination of the second measured value are preferably carried out simultaneously or at least within a time span in which the force or the moment does not change. The measured values qualitatively and quantitatively represent the same force or moment.

Since the first combination of the magnetic field sensors and the second combination of the magnetic field sensors are respectively sufficient for measuring the force or the torque, the first measured value and the second measured value are the same if the arrangement operates without errors. According to the invention, the first measured value is compared with the second measured value, so that the result of this comparison is based on an error-free function or on a faulty function of the arrangement

can be closed. If it is concluded by the comparison of an erroneous function of the arrangement, it is preferably also determined which of the individual magnetic field sensors has a faulty function.

A particular advantage of the method according to the invention is that, as a result of the comparison of the measured values, a largely reliable statement as to whether the arrangement operates faultlessly or incorrectly.

The at least two magnetization regions can be permanently or temporarily magnetized. The magnetization regions are preferably permanent

magnetized, so that the magnetization is formed by a permanent magnetization. Alternatively, the arrangement further comprises at least one magnet for magnetizing the magnetization regions, so that the

Magnetization of the magnetization regions is basically temporary. The at least one magnet can be formed by a permanent magnet or preferably by an electromagnet. The permanently or temporarily magnetized magnetization regions are in a state of the load unloaded by a force or by a moment

Machine element to the outside of the magnetization preferably magnetically neutral, so that no technically relevant magnetic field outside the magnetization ranges can be measured.

The magnetization areas each represent a part of the volume of the

Machine element. The magnetization regions are preferably each annular, wherein the axis of the machine element also forms a central axis of the respective ring shape. Particularly preferred are the

Magnetizing regions each have the shape of a coaxial with the axis of the machine element hollow cylinder.

The magnetization regions preferably each have a high magnetostriction.

The magnetization regions are preferably axially spaced from one another

arranged, between each of two adjacent magnetization regions each one of the magnetically neutral regions may be arranged. Insofar as more than two of the magnetization regions are present, they preferably each have an equal distance from one another.

Axially adjacent to the circumferentially extending around the axis

Magnetization regions preferably have opposite polarities, i. H. they have an opposite sense of circulation.

At least in the magnetization region, the machine element consists of a magnetostrictive or magnetoelastic material. This preferably exists

Machine element made entirely of magnetostrictive or magnetoelastic material. Preferably, the machine element consists of a steel.

The machine element preferably has the shape of a prism or a cylinder, wherein the prism or the cylinder is arranged coaxially to the axis. The Prism or the cylinder is preferably straight. This preferably has

Machine element in the form of a right circular cylinder, wherein the

Circular cylinder is arranged coaxially to the axis. For special

Embodiments, the prism or the cylinder is conical. The prism or the cylinder can also be hollow. This is especially preferred

Machine element in the form of a straight hollow circular cylinder, wherein the hollow circular cylinder is arranged coaxially with the axis.

The machine element is preferably formed by a shaft, by a Flohlwelle, by a shift fork, by a flange or by a Flohlflansch. The shaft, the shift fork or the flange can be used for loads

be designed different forces and moments and, for example, a

Component of a sensor bottom bracket, a roll stabilizer or a

Be fertilizer spreader. In principle, the machine element can also be formed by completely different types of machine elements.

The magnetic field sensors are preferably each formed by a Flalbleitersensor. Alternatively, the at least two magnetic field sensors are preferably each formed by an MR sensor, by a flat sensor, by a field plate, by a SQUID, by a coil element, by a Förster probe or by a fluxgate magnetometer. In principle, other sensor types can be used insofar as they are suitable for measuring the axial directional component of the magnetic field produced by the inverse-magnetostrictive effect.

The magnetic field sensors preferably have an equal distance from the axis of the machine element. In principle, the magnetic field sensors can be arranged outside the machine element or, preferably, also within a flea space of the machine element; For example, when the machine element is formed by a Flohlwelle or by a Flohlflansch.

The magnetic field sensors preferably each have an axial position such as one of the magnetization regions. The magnetic field sensors preferably each have one axial position, which is a middle axial position of the

Magnetization ranges are equal.

The magnetic field sensors preferably each have an identical tangential or

same circumferential position as at least one other of the magnetic field sensors on. These at least two magnetic field sensors preferably lie together on a straight line parallel to the axis. These magnetic field sensors having at least two identical tangential or identical circumferential position are axially adjacent and preferably each have an identical axial position as axially adjacent magnetization regions. It is also possible for two magnetic field sensors having the same tangential or identical circumferential position to have the same axial position as only one of the magnetization regions.

At least one of the magnetization regions preferably has the same axial position as at least two of the magnetic field sensors, so that this

Magnetization region are assigned to two of the magnetic field sensors. These two magnetic field sensors having the same axial position are preferably arranged opposite one another with respect to the axis, so that they have a midpoint angle of 180 ° to one another and a straight line intersecting the two magnetic field sensors intersects the axis perpendicularly. More preferably, each of the

Magnetization regions on the same axial position as two of the magnetic field sensors, so that each of the magnetization regions at least two of the

Magnetic sensors are assigned.

The arrangement preferably furthermore comprises a measurement signal processing unit, which is designed to determine and compare the measured values. The

Magnetic field sensors are preferably electrically connected individually to the measurement signal processing unit, so that in each case a single measurement signal from each of the

Magnetic field sensors is passed to the measurement signal processing unit. Preferred embodiments of the method according to the invention comprise a step in which the magnetic field sensors are calibrated individually. This compensates for an offset and the sensitivity of the magnetic field sensors to one another be matched, so that the reliability of error detection is increased again.

Particularly preferably, at least three of the measured values are determined and compared with one another. Accordingly, there are preferably at least three of

Combinations of at least two of the magnetic field sensors, each of these combinations being sufficient to measure the force or the moment. There is a determination of a third measurement of the force or the moment with a third of the combinations of the magnetic field sensors, while the force or the moment acts. The first measured value, the second measured value and the third measured value are compared with one another. More preferably, at least four of the measured values are determined and compared with each other. Those embodiments in which three or more of the measured values are determined and compared preferably comprise a further step, in which, in the event of deviations between the measured values, the one or more of the magnetic field sensors which do not work correctly are determined. In addition, it can be determined if one of the

Magnetization areas has a faulty function.

In preferred embodiments of the method according to the invention, absolute values of the differences between the

Measured values or squares of the differences between the measured values are formed. It is preferably a sum of the absolute amounts of the differences between the measured values or a sum of the squares of the differences between the measured values

Measured values formed. The corresponding sum is preferably used as a test signal.

Preferably, an error signal is output if the sum of the absolute amounts of the differences between the measured values or the sum of the squares of the differences of the differences between the measured values is a pre-defined one

Exceeds maximum size. The maximum dimension defines in advance the difference between the measured values that the arrangement is considered to be free from defects. The error signal is preferably reported to a higher-level controller or to an operator of the arrangement, so that the parent Control or the operator is aware that the arrangement no longer measures error-free.

In a first particularly preferred embodiment of the method according to the invention, the arrangement is for measuring a moment acting on the machine element and lying in the axis, that is, in the direction of the axis. H. formed a torsional moment. The machine element has two of the magnetization regions of opposite polarities. Each of the magnetization regions has the same axial position as two of the magnetic field sensors, wherein these two are arranged opposite to each other, a magnetic position sensors having the same axial position with respect to the axis. Each two of the four magnetic field sensors have an identical tangential position and are axially adjacent. A first of the four magnetic field sensors outputs a measurement signal ai. The magnetic field sensor having the first magnetic field sensor opposite the axis and having the same axial position as the first magnetic field sensor forms a second magnetic field sensor which outputs a measurement signal a2. The measurement signals ai and a2 represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with opposite

Sense of direction; d. H. the measurement signals ai and a2 represent the axial

Directional components with different signs. The one to the first

Magnetic field sensor axially adjacent and a same circumferential position as the first magnetic field sensor having magnetic field sensor forms a third of the magnetic field sensors, which outputs a measurement signal bi. The measurement signals ai and bi represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with the same sense of direction; d. H. the measurement signals ai and bi represent the axial direction components with the same sign. The magnetic field sensor having the third magnetic field sensor opposite to the axis and having the same axial position as the third magnetic field sensor constitutes a fourth of the magnetic field sensors which outputs a measurement signal b2. The measurement signals bi and b2 represent the axial direction components of the due to the inverse magnetostrictive effect

occurring magnetic field with opposite direction sense; d. H. the

Measurement signals bi and b2 represent the axial direction components with different signs. At least two of the measured values of the moment are each determined according to one of the following mathematical rules:

a 1 - a 2 - b 1 + b 2

M L - - a r + b 2

 M =

 2

a 2 + b x

M 3 = -

From the mathematical rules, it is apparent that there are at least three of the combinations of the magnetic field sensors, which are respectively sufficient for the measurement of the moment. The first combination includes the first, second, third and fourth magnetic field sensors. The second combination includes the first and fourth magnetic field sensors. The third combination includes the second and third magnetic field sensors.

Preferably, the test signal T is determined according to one of the following instructions:

Figure imgf000014_0001

T = (M 1 - M 2 ) 2

T = (M 1 - Mo ·) 2

t = (M 2 - M 3 ) 2

Preferably, not only two, but all of the three measured values Mi, M2 and M3 are determined. Preferably, the test signal T becomes one of the following

Rules determined:

Figure imgf000014_0002

T = (M 1 M 2 ) 2 + (Mi M 3 ) 2 + (M 2 M 3 ) 2 In a second particularly preferred embodiment of the method according to the invention, the arrangement is likewise designed to measure a moment acting on the machine element and lying in the axis, ie a torsional moment. The machine element has three of the magnetization regions of alternating polarities. The axially middle of the magnetization regions has the same axial position as two of the magnetic field sensors, wherein these two are arranged opposite one another with the same axial position magnetic field sensors with respect to the axis. Each two of the four magnetic field sensors have an identical tangential position and are axially adjacent. The axially outer magnetization regions each have the same axial position as one of the four magnetic field sensors. A first of the four

Magnetic field sensors have the same axial position as one of the axially outer magnetization regions. The first magnetic field sensor outputs a measurement signal ai. The axially adjacent to the first magnetic field sensor and a same circumferential position as the first magnetic field sensor having

Magnetic field sensor forms a second of the magnetic field sensors, which a

Output signal bi. The measurement signals ai and bi represent the axial

Directional components of the because of the inverse magnetostrictive effect

occurring magnetic field with the same sense of direction; d. H. the measurement signals ai and bi represent the axial direction components with the same sign. The opposite the second magnetic field sensor with respect to the axis and having an identical axial position as the second magnetic field sensor

Magnetic field sensor forms a third of the magnetic field sensors, which a

Output signal b2. The measuring signals bi and b2 represent the axial

Directional components of the because of the inverse magnetostrictive effect

occurring magnetic field with opposite direction sense; d. H. the

Measurement signals bi and b2 represent the axial direction components with different signs. The third magnetic field sensor axially adjacent and a same circumferential position as the third magnetic field sensor having magnetic field sensor forms a fourth of the magnetic field sensors, which

Measuring signal 02 outputs. The measuring signals b2 and 02 represent the axial

Directional components of the because of the inverse magnetostrictive effect

occurring magnetic field with the same sense of direction; ie the measuring signals b2 and C2 represent the axial direction components with the same sign.

At least two of the measured values of the moment are determined according to one of the following regulations:

Figure imgf000016_0001

di + b 2

M 2

 2

bi + c 2

M 3

 2

 From the mathematical rules, it is apparent that there are at least three of the combinations of the magnetic field sensors, which are respectively sufficient for the measurement of the moment. The first combination includes the first, second, third and fourth magnetic field sensors. The second combination includes the first and fourth magnetic field sensors. The third combination includes the second and third magnetic field sensors.

Preferably, the test signal T is determined according to one of the following instructions:

T = \ M 1 - M 2 \

Figure imgf000016_0002

T = (M 2 -M 3 ) 2

Preferably, not only two, but all of the three measured values Mi, M2 and M3 are determined. Preferably, the test signal T becomes one of the following

Rules determined:

Figure imgf000016_0003

T = (M 1 - M 2 ) 2 + (Mi M 3 ) 2 + (M 2 M 3 ) 2 In a third particularly preferred embodiment of the method according to the invention, the arrangement is again for measuring one on the

Machine element acting and in-axis torque, d. H. formed a torsional moment. The machine element has three of

Magnetization areas with alternating polarities. Everyone who

Magnetization regions has the same axial position as two of the

Magnetic sensors, wherein these two have an identical axial position

magnetic field sensors are arranged with respect to the axis opposite. Each three of the six magnetic field sensors have an identical tangential position and are axially adjacent. A first of the six

Magnetic field sensors have the same axial position as one of the axially outer magnetization regions. The first magnetic field sensor outputs a measurement signal ai. The magnetic field sensor having the first magnetic field sensor opposite the axis and having the same axial position as the first magnetic field sensor forms a second magnetic field sensor which outputs a measurement signal a2. The measurement signals ai and a2 represent the axial direction components of the inverse magnetostrictive effect

occurring magnetic field with opposite direction sense; d. H. the

Measurement signals ai and a2 represent the axial direction components with different signs. The magnetic field sensor axially adjacent to the first magnetic field sensor and having the same circumferential position as the first magnetic field sensor forms a third magnetic field sensor

Output signal bi. The third magnetic field sensor has the same axial position as the middle magnetization region. The measuring signals ai and bi

represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with the same sense of direction; d. H. the measurement signals ai and bi represent the axial direction components with the same sign. The magnetic field sensor having the third magnetic field sensor opposite to the axis and having the same axial position as the third magnetic field sensor constitutes a fourth of the magnetic field sensors which outputs a measurement signal b2. The measurement signals bi and b2 represent the axial direction components of the due to the inverse magnetostrictive effect

occurring magnetic field with opposite direction sense; ie the Measurement signals bi and b2 represent the axial direction components with different signs. The third magnetic field sensor axially adjacent and a same circumferential position as the first magnetic field sensor and the third magnetic field sensor having magnetic field sensor forms a fifth of

Magnetic field sensors, which outputs a measurement signal ci. The measurement signals bi and ci represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with the same sense of direction; d. H. the measurement signals bi and ci represent the axial direction components with the same sign. The magnetic field sensor having the fifth magnetic field sensor opposite to the axis and having the same axial position as the fifth magnetic field sensor constitutes a sixth of the magnetic field sensors which outputs a measurement signal C2. The measurement signals ci and C2 represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with opposite sense of direction; d. H. the

Measurement signals ci and C2 represent the axial direction components with different signs. At least two of the measured values of the moment are determined according to one of the following regulations:

Figure imgf000018_0001

b + a 2

M 7

2 bi + c 2

M 8 =

 2

b 2 + Ci

M g =

 2

 From the mathematical rules, it is apparent that there are at least nine of the combinations of the magnetic field sensors, each of which is sufficient to measure the moment. The first combination comprises the first, the second, the third, the fourth, the fifth and the sixth magnetic field sensor. The second combination includes the first, third, fourth and sixth magnetic field sensors. The third combination includes the second, third, fourth and fifth magnetic field sensors. The fourth combination includes the first, second, third and fourth magnetic field sensors. The fifth combination includes the third, fourth, fifth and sixth magnetic field sensors. The sixth

Combination includes the first and the fourth magnetic field sensor. The seventh combination includes the third and second magnetic field sensors. The eighth combination includes the third and sixth magnetic field sensors. The ninth combination includes the fourth and fifth magnetic field sensors.

Preferably, not only two but at least four or more preferably all of the nine measured values Mi to MQ are determined. Preferably, the test signal T is correspondingly as in the first and second preferred

Embodiment determined.

In a fourth particularly preferred embodiment of the method according to the invention, the arrangement is again for measuring one on the

Machine element acting and in-axis torque, d. H. formed a torsional moment. The machine element has three of

Magnetization areas with alternating polarities. The two axially outwardly arranged magnetization regions each have the same axial position as two of the magnetic field sensors, wherein these two magnetic field sensors having an identical axial position are arranged opposite one another with respect to the axis. The axially middle magnetization region has the same axial position as four of the magnetic field sensors, two of these each Magnetic sensors are arranged directly next to each other and form a pair. Because of this immediately adjacent arrangement, the magnetic field sensors of each of the two pairs have substantially the same position. The two pairs of identical axial positions are arranged opposite each other with respect to the axis. Four of the eight magnetic field sensors each have an identical tangential position and are axially adjacent. A first of the eight

Magnetic field sensors have the same axial position as one of the axially outer magnetization regions. The first magnetic field sensor outputs a measurement signal ai. The magnetic field sensor having the first magnetic field sensor opposite the axis and having the same axial position as the first magnetic field sensor forms a second magnetic field sensor which outputs a measurement signal a2. The measurement signals ai and a2 represent the axial direction components of the inverse magnetostrictive effect

occurring magnetic field with opposite direction sense; d. H. the

Measurement signals ai and a2 represent the axial direction components with different signs. The pair of magnetic field sensors which is axially adjacent to the first magnetic field sensor and has the same circumferential position as the first magnetic field sensor comprises a third of the first magnetic field sensor

Magnetic field sensors, which outputs a measurement signal bn, and a fourth of the magnetic field sensors, which outputs a measurement signal bi2. The third magnetic field sensor and the fourth magnetic field sensor have the same axial position as the axially middle magnetization region. The measurement signals ai, bn, and bi2 represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with the same sense of direction; d. H. the measurement signals ai, bn and bi2 represent the axial direction components with the same sign. The third and fourth magnetic field sensor with respect to the axis

opposite and a same axial position as the third and fourth

Magnetic field sensor comprising a fifth of the magnetic field sensors, which outputs a measurement signal b2i, and a sixth of the magnetic field sensors, which outputs a measurement signal b22. The measurement signals bn and b2i represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with opposite sense of direction; d. H. the

Measurement signals bn and b2i represent the axial direction components with different signs. The measurement signals b2i and b22 represent the axial direction components of the inverse magnetostrictive effect

occurring magnetic field with the same sense of direction; d. H. the measurement signals b2i and b22 represent the axial direction components with the same sign. The axially adjacent to the third magnetic field sensor and a same circumferential

 Position as the first magnetic field sensor, the third magnetic field sensor and the fourth magnetic field sensor having magnetic field sensor forms a seventh of

Magnetic field sensors, which outputs a measurement signal ci. The measurement signals bn and ci represent the axial direction components of the magnetic field occurring due to the inverse magnetostrictive effect with the same sense of direction; d. H. the measurement signals bn and ci represent the axial direction components with the same sign. The one opposite to the seventh magnetic field sensor with respect to the axis and an identical axial position as the seventh

Magnetic field sensor having magnetic field sensor forms an eighth

Magnetic field sensors, which outputs a measurement signal C2. The measurement signals ci and C2 represent the axial direction components due to the magnetic field occurring inverse magnetostrictive effect with opposite

Sense of direction; d. H. the measurement signals ci and C2 represent the axial

Directional components with different signs. At least two of the measured values of the moment are determined according to one of the following regulations:

Figure imgf000021_0001
b l + a 2

M 6

 2

bn + C 2

M 7

2

Figure imgf000022_0001

 From the mathematical rules, it is apparent that there are at least eight of the combinations of the magnetic field sensors, each of which is sufficient to measure the moment. The first combination comprises the first, the second, the third, the fourth, the fifth, the sixth, the seventh and the eighth

Magnetic field sensor. The second combination includes the first, second, third, fifth, seventh and eighth magnetic field sensors. The third combination includes the first, the third, the fifth and the eighth

Magnetic field sensor. The fourth combination includes the third, fifth, seventh and eighth magnetic field sensors. The fifth combination includes the first and fifth magnetic field sensors. The sixth combination includes the third and second magnetic field sensors. The seventh combination includes the third and eighth magnetic field sensors. The eighth combination comprises the fifth and seventh magnetic field sensors.

Preferably, not only two but at least four or more preferably all of the eight measured values Mi to Me are determined. Preferably, the test signal T is correspondingly as in the first and second preferred

Embodiment determined.

The described four particularly preferred embodiments preferably also have features which are described above as being preferred.

The arrangement according to the invention serves to measure a force and / or a moment on a machine element extending in an axis. The machine element has at least two magnetization areas extending in each case around the axis for one magnetization in each case. The arrangement comprises at least four magnetic field sensors each for measuring a axial direction component of a magnetic field caused by the magnetization and by the force and / or by the moment. There are at least two combinations of at least two of the magnetic field sensors each. Each of these combinations is sufficient for measuring the force or the moment. The

Arrangement further comprises a measurement signal processing unit, which is designed for carrying out the method according to the invention. The

Measurement signal processing unit is preferably designed for carrying out one of the described preferred embodiments of the method according to the invention. Moreover, the arrangement preferably also has features which are specified in connection with the method according to the invention.

The measurement signal processing unit is preferably formed by a microcontroller. In a broader sense, the measurement signal processing unit is preferably a

Calculated unit formed.

Further details, advantages and developments of the invention will become apparent from the following description of preferred embodiments of the invention, with reference to the drawing. Show it:

Fig. 1 shows a first preferred embodiment of an inventive

 Arrangement in two views;

Fig. 2 shows a second preferred embodiment of the invention

 Arrangement in two views;

Fig. 3 shows a third preferred embodiment of the invention

 Arrangement in two views; and

Fig. 4 shows a fourth preferred embodiment of the invention

 Arrangement in two views.

Fig. 1 shows a first preferred embodiment of an inventive

Arrangement in a cross-sectional view and in a longitudinal sectional view. The

Arrangement comprises a machine element made of a steel in the form of a Hollow flange 01, which extends in an axis 03. On the hollow flange 01 acts a torsional moment Mt, which can be measured with the inventive arrangement.

The hollow flange 01 has two magnetization regions 04 in the form of circumferential tracks. The two magnetization regions 04 are permanently magnetized and oppositely poled, which in each case by a circulating sense

illustrative arrow 05 is shown. The two magnetization regions 04 form a primary sensor for the measurement of the torsional moment Mt using the inverse-magnetostrictive effect.

The arrangement further comprises four magnetic field sensors 06, which are located in the interior of the hollow flange 01. The four magnetic field sensors 06 are at the same distance from the axis 03.

The four magnetic field sensors 06 each serve to measure an axial

Direction component of a magnetization occurring by the magnetization of the magnetization regions 04 and by the torsional moment Mt due to the inverse magnetostrictive effect magnetic field. A magnetic field direction of this magnetic field is at each of the positions of the magnetic field sensors 06 through one of the respective

Magnetic direction illustrative arrow 07 shown. A positive

Measuring direction of the magnetic field sensors 06 is illustrated by the symbol used for the magnetic field sensors 06 with an arrow.

Two of the four magnetic field sensors 06 have the same axial position as a first one of the magnetization regions 04. Two more of the four magnetic field sensors 06 have the same axial position as a second one of the magnetization regions 06.

A first magnetic field sensor 11 of the four magnetic field sensors 06 outputs a signal ai. The first magnetic field sensor 11 with respect to the axis 03 opposite magnetic field sensor 06 forms a second magnetic field sensor 12 which outputs a signal a2. The magnetic field sensor axially adjacent to the first magnetic field sensor 11 06 forms a third magnetic field sensor 13, which outputs a signal bi. The third magnetic field sensor 13 with respect to the axis 03 opposite

Magnetic field sensor 06 forms a fourth magnetic field sensor 14, which outputs a signal b2.

The arrangement further comprises a microcontroller (not shown), which is used for measuring signal processing and for carrying out an inventive

A method for checking the arrangement is configured.

Fig. 2 shows a second preferred embodiment of the invention

Arrangement in a cross-sectional view and in a longitudinal sectional view. This embodiment is initially similar to the embodiment shown in FIG. in the

In contrast to the first embodiment shown in FIG. 1, the hollow flange 01 has three of the magnetization regions 04, which are alternately poled. The first magnetic field sensor 11 of the four magnetic field sensors 06 in turn outputs the signal ai. The second magnetic field sensor 12 is axially adjacent to the first magnetic field sensor 11 and outputs the signal bi. The third magnetic field sensor 13 is disposed opposite to the first magnetic field sensor 11 with respect to the axis 03 and outputs the signal b2. The fourth magnetic field sensor 14 is the third

Magnetic field sensor 13 axially adjacent and outputs the signal 02 from.

Fig. 3 shows a third preferred embodiment of the invention

Arrangement in a cross-sectional view and in a longitudinal sectional view. This embodiment is initially similar to the embodiment shown in FIG. in the

In contrast to the second embodiment shown in FIG. 2, FIG

Arrangement six of the magnetic field sensors 06. The first magnetic field sensor 11 of the six magnetic field sensors 06 in turn outputs the signal ai. The second

Magnetic field sensor 12 is disposed opposite to first magnetic field sensor 11 with respect to axis 03 and outputs signal a2. The third magnetic field sensor 13 is axially adjacent to the first magnetic field sensor 11 and outputs the signal bi. The fourth magnetic field sensor 14 is the third with respect to the axis 03

Magnetic sensor 13 disposed opposite and outputs the signal b2. A fifth magnetic field sensor 15 of the six magnetic field sensors 06 is the third Magnetic field sensor 13 axially adjacent and outputs the signal ci. A sixth magnetic field sensor 16 of the six magnetic field sensors 06 is arranged opposite to the fifth magnetic field sensor 15 with respect to the axis 03 and outputs the signal C2.

Fig. 4 shows a fourth preferred embodiment of the invention

Arrangement in a cross-sectional view and in a longitudinal sectional view. This embodiment initially resembles the embodiment shown in FIG. in the

In contrast to the third embodiment shown in FIG. 3, FIG

Arrangement eight of the magnetic field sensors 06. The first magnetic field sensor 11 of the six magnetic field sensors 06 in turn outputs the signal ai. The second

Magnetic field sensor 12 is disposed opposite to first magnetic field sensor 11 with respect to axis 03 and outputs signal a2. The third magnetic field sensor 13 is axially adjacent to the first magnetic field sensor 11 and outputs the signal bn. The fourth magnetic field sensor 14 is located immediately next to the third magnetic field sensor 13 outputs the signal bi2. The fifth magnetic field sensor 15 is disposed opposite to the third magnetic field sensor 13 with respect to the axis 03 and outputs the signal b2i. The sixth magnetic field sensor 16 is located immediately next to the fifth magnetic field sensor 13 outputs the signal b22. A seventh magnetic field sensor 17 of the eight magnetic field sensors 06 is axially adjacent to the third magnetic field sensor 13 and outputs the signal ci. An eighth

Magnetic field sensor 18 of the six magnetic field sensors 06 is arranged opposite to the seventh magnetic field sensor 17 with respect to the axis 03 and outputs the signal C2.

LIST OF REFERENCES

Machine element in the form of a hollow flange

axis

 magnetization field

 of circulation

 magnetic field sensor

 magnetic field direction

first magnetic field sensor

second magnetic field sensor

third magnetic field sensor

fourth magnetic field sensor

fifth magnetic field sensor

sixth magnetic field sensor

seventh magnetic field sensor

eighth magnetic field sensor

Claims

claims
A method of testing an arrangement for measuring a force and / or torque (Mt) on an axis (03) extending
 Machine element (01), wherein the machine element (01) at least two circumferentially around the axis (03) extending around
 Magnetization regions (04) for each having a magnetization, wherein the arrangement comprises at least four magnetic field sensors (06) for measuring an axial component of a caused by the magnetization as well as by the force and / or by the moment (Mt) magnetic field, wherein there are at least two combinations of at least two of each
 Magnetic field sensors (06), wherein each of the combinations for measuring the force or the moment (Mt) is sufficient, and wherein the method comprises the following steps:
 - determining a first measurement of the force or moment (Mt) with a first one of the combinations of the magnetic field sensors (06);
 Determining a second measurement of the force or moment (Mt) with a second one of the combinations of the magnetic field sensors (06); and
- Compare the first measured value with the second measured value.
2. The method according to claim 1, characterized in that furthermore a
 Determining a third measured value of the force or the torque (Mt) with a third of the combinations of the magnetic field sensors (06) takes place, wherein the comparison of the first measured value, the second measured value and the third measured value takes place.
3. The method according to claim 1 or 2, characterized in that for
 Comparing the measured values absolute amounts of differences between the measured values or squares of differences between the measured values are formed.
Method according to claim 3, characterized in that it comprises a further step in which a sum of the absolute amounts of the Differences between the measured values or a sum of the squares of the differences between the measured values is formed.
5. The method according to claim 4, characterized in that an error signal is output if the sum of the absolute amounts or the sum of the squares of the differences exceeds a predefined maximum amount.
6. The method according to any one of claims 1 to 5, characterized in that the magnetic field sensors (06) each have a same tangential position as at least one other of the magnetic field sensors (06).
7. The method according to any one of claims 1 to 6, characterized in that the magnetic field sensors (06) each have an axial position of one of
 Magnetizing regions (04).
8. The method according to claim 7, characterized in that at least one of the magnetization regions (04) has the same axial position as two of the magnetic field sensors (06), wherein these two magnetic field sensors (06) with respect to the axis (03) are arranged opposite one another.
9. The method according to claim 8, characterized in that each of the
 Magnetization regions (04) the same axial position as two of the axis (03) arranged opposite magnetic field sensors (06), and that in each case two of the magnetic field sensors (06) have a same tangential position and are axially adjacent, wherein a first of the Magnetic field sensors (06, 11) outputs a measurement signal ai, wherein the first magnetic field sensor (11) with respect to the axis (03) opposite magnetic field sensor (06, 12) forms a second of the magnetic field sensors (06, 12), which outputs a measurement signal a2 , Wherein the measurement signals ai and a2, the axial direction components of the magnetic field occurring with
represent the opposite sense of direction, wherein the magnetic field sensor (06, 13) axially adjacent to the first magnetic field sensor (11) forms a third of the magnetic field sensors (06, 13), outputs a measurement signal bi, wherein the measurement signals ai and bi are the axial direction components represent the magnetic field occurring with the same sense of direction, wherein the third magnetic field sensor (13) with respect to the axis (03) opposite magnetic field sensor (06, 14) a fourth of the
 Magnetic field sensors (06, 14), which outputs a measurement signal b2, wherein the measurement signals bi and b2 represent the axial direction components of the magnetic field occurring with opposite sense of direction, and wherein the at least two measured values in each case according to one of the following rules:
a 1 - a 2 - b 1 + b 2
M 1
 4
a + b 2
M 2
 2
a 2 +
M 3
 2
10. Arrangement for measuring a force and / or a moment (Mt) on a machine element (01) extending in an axis (03), wherein the machine element (01) has at least two magnetization areas extending circumferentially around the axis (03). 04) for each one
 Magnetization, wherein the arrangement is at least four
 Magnetic field sensors (06) for measuring an axial direction component of a magnetic field caused by the magnetization and by the force and / or by the moment (Mt), wherein there are at least two combinations of at least two of the magnetic field sensors (06), wherein each of the combinations is sufficient for measuring the force or the moment (Mt), and wherein the arrangement further comprises a
 Measuring signal processing unit, which is designed for carrying out a method according to one of claims 1 to 9.
PCT/DE2019/100292 2018-03-29 2019-03-28 Arrangement for measuring a force or a torque on a machine element and method for testing the arrangement WO2019185095A1 (en)

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