Systems for detecting torque and rotation angle

Abstract

A system (1) for detecting torque and rotation angle comprises a rotor unit (10) and a stator unit (20) which are rotatable about a rotation axis (X), wherein the stator unit is arranged in a fixed position and is separated from the rotor unit by a radial air gap (30) relative to the rotation axis (X); the rotor unit comprises a strain gauge (15) for detecting torque acting on the rotor unit; the rotor unit comprises a plurality of dipole magnets (14) arranged spaced apart from each other; the stator unit comprises a magnetic field sensor (24) for measuring the magnetic field of the dipole magnets when the rotor unit rotates; the stator unit comprises a primary coil (21) and the rotor unit comprises a secondary coil (11); a primary voltage in the primary coil induces a secondary voltage in the secondary coil; the residual magnetism of each dipole magnet is greater than / equal to 1000 mT, preferably greater than / equal to 1400 mT; and the secondary coil comprises a plurality of ferrite elements (110).

Description

Technical Field

[0001] The invention relates to a system for detecting torque and rotation angle. Background Art

[0002] In industrial measurement technology, it is necessary to detect physical variables of industrially manufactured products, such as torque, rotation angle, etc. Therefore, in test bench technology, the torque and rotation angle of rotating parts such as internal combustion engines, electric motors, transmissions, pumps, etc. are detected. Even when cutting workpieces, the torque and rotation angle of rotating parts must be detected.

[0003] The applicant provides a system for detecting torque and rotation angle, which is named KiTorq and is recorded in data sheet 4550A_000-880d-08.20. For the purposes of the present invention, KiTorq constitutes prior art. KiTorq has a rotor unit and a stator unit. The rotor unit is designed as a flange and can be fastened to any rotating component by bolting. The rotor unit is designed for a rotation speed of up to 20,000 min-1. -1 The stator unit is arranged in a fixed position and is separated from the rotor unit by a radial air gap with respect to the rotation axis.

[0004] The rotor unit has a strain gauge. The strain gauge includes a measuring grid and a bridge circuit. When a voltage is applied to the measuring grid, the measuring grid has a resistance. When the measuring grid is stretched or compressed, the resistance changes, and the change in resistance generates a measurement signal in the bridge circuit. The strain gauge thus detects the torque acting on the rotor unit. The strain gauge dynamically detects the torque and generates up to 10,000 measurement signals per second at a sampling rate of up to 35 kSample. The measurement signal has a resolution of 24 Bit.

[0005] The rotor unit has a plurality of dipole magnets arranged at a distance from one another. The stator unit has a magnetic field sensor that measures the magnetic field of the dipole magnets during the rotation of the rotor unit. By counting the measured magnetic fields and knowing the distances between the dipole magnets, the system determines the rotation angle of the rotor unit.

[0006] In order to transmit the measurement signal from the rotor unit to the stator unit, the rotor unit has a rotor antenna and the stator unit has a stator antenna. The measurement signal is transmitted contactlessly, wherein the rotor antenna transmits the measurement signal to the stator antenna. For this purpose, a transmission frequency of 13.56 MHz is used in the Industrial Scientific and Medical (ISM) band and a transmission rate of up to 1.4 Mbitsec is achieved. -1 data transfer rate.

[0007] In order for the strain gauge and the rotor antenna to work, the rotor unit must be powered. For this purpose, the stator unit has a primary coil and the rotor unit has a secondary coil. The primary coil and the secondary coil are inductively coupled to each other. The primary voltage in the primary coil induces a secondary voltage in the secondary coil. The inductive coupling of the primary coil to the secondary coil is contactless and occurs within the ISM band with a carrier frequency of 115kHz to 130kHz.

[0008] The dipole magnet is made of a magnetized ferrite powder / rubber mixture. The remanence of the dipole magnet is relatively weak at a low 200 mT. This weak remanence is easily disturbed by external magnetic fields and thus distorts the determination of the rotation angle.

[0009] In order to achieve inductive coupling, the secondary coil has an iron powder / resin mixture. The iron powder / resin mixture can be quickly stirred and easily arranged on the rotor unit in a curved shape with a spatula, where it quickly hardens. In particular, the same iron powder / resin mixture can be used for rotor units with different radii of curvature. Therefore, the iron powder / resin mixture can achieve low-cost manufacturing with high variability. However, the newly stirred iron powder / resin mixture contains pores, which are still retained after the iron powder / resin mixture hardens, resulting in a low magnetic permeability. As a result, the inductive coupling efficiency of the primary coil and the secondary coil is low.

[0010] For these reasons, the dipole magnet and the magnetic field sensor as well as the primary and secondary coils must be placed close together. The radial air gap between the stator unit and the rotor unit is only 1.0 mm and must comply with a narrow radial air gap tolerance of + / -0.5 mm. In order to maintain such a narrow radial air gap tolerance, the rotor unit should be manufactured with a balancing mass according to DIN ISO 1940-1 of G 2.5, which, however, makes the manufacture of the KiTorq complex and expensive.

[0011] Furthermore, it often happens that after the rotor unit is fastened to the rotating component, there is not enough space next to the rotating component to mount the stator unit next to the rotor unit so that the magnetic field sensor can be brought closest to the dipole magnet. However, the further the magnetic field sensor is from the dipole magnet, the more errors the magnetic field sensor measures of the magnetic field of the dipole magnet, which leads to a falsification of the determination of the rotation angle. Summary of the invention

[0012] A first object of the present invention is to provide a system for detecting torque and rotation angle, the system comprising a rotor unit and a stator unit, which are separated from each other by a radial air gap about the rotation axis, which air gap is larger than the air gap of the prior art according to KiTorq and which has a greater tolerance than the prior art according to KiTorq.

[0013] A second object of the present invention is to provide a system for detecting torque and rotation angle, wherein the detection of the rotation angle by the system is not easily interfered by an external magnetic field.

[0014] And a third object of the invention is to find a system for detecting torque and rotation angle which can be manufactured at a lower cost than the prior art according to KiTorq.

[0015] Finally, a fourth object of the present invention is to provide a system for detecting torque and rotation angle in which the stator unit can be easily and quickly installed near the rotor unit so that the magnetic field sensor is closest to the dipole magnet.

[0016] At least one of the above-mentioned purposes is achieved by the technical solution according to the present invention.

[0017] The present invention relates to a system for detecting torque and rotation angle; the system has a rotor unit which can rotate around a rotation axis; the system has a stator unit which is arranged in a fixed position and is separated from the rotor unit by a radial air gap about the rotation axis; wherein the rotor unit has a strain gauge which detects the torque acting on the rotor unit; wherein the rotor unit has a plurality of dipole magnets which are arranged spaced apart from each other; wherein the stator unit has a magnetic field sensor which measures the magnetic field of the dipole magnets when the rotor unit rotates; wherein the stator unit has a primary coil and the rotor unit has a secondary coil; wherein a primary voltage in the primary coil causes a secondary voltage in the secondary coil; wherein each dipole magnet has a residual magnetism greater than / equal to 1000 mT, preferably greater than / equal to 1400 mT; and wherein the secondary coil has a plurality of ferrite elements.

[0018] According to the invention, the dipole magnet of the rotor unit has a very strong remanence. Compared to the magnetized ferrite powder / rubber mixture of the dipole magnet according to KiTorq, the remanence of the dipole magnet according to the invention is at least five times greater. Due to this strong remanence, the magnetic field sensor of the stator unit can measure the magnetic field of the dipole magnet from a greater distance. In addition, this strong remanence is not easily disturbed by external magnetic fields.

[0019] Ferrite components consist of very pure iron-oxygen compounds that are uniformly pressed under high pressure into a pressed product (Pressling). Therefore, ferrite components are characterized by a large proportion of magnetic material and are highly dense. Ferrite components therefore have high magnetic permeability. Compared with the iron powder / resin mixture according to KiTorq, ferrite components also improve the inductive coupling efficiency between the primary coil and the secondary coil. And, due to the improved efficiency, inductive coupling can occur over a greater distance.

[0020] Therefore, the combination of strong residual dipole magnets and ferrite elements in the secondary coil of the system according to the invention has a synergistic effect, namely that the radial air gap from the rotor unit to the stator unit is allowed to be increased and the permissible radial air gap tolerance is also allowed to be enlarged.

[0021] Additionally, ferrite components are inexpensive to purchase, which makes the system inexpensive to manufacture.

[0022] Preferred embodiments of the system for detecting torque and rotation angle are given in the following description.

[0023] In a preferred embodiment of the system, the radial air gap is greater than / equal to 2.0 mm and has a radial air gap tolerance of + / -1.5 mm.

[0024] Compared to the prior art system for detecting torque and rotation angle according to KiTorq, the radial air gap is now at least twice as large and the permissible radial air gap tolerance is even three times as large.

[0025] In a preferred embodiment of the system, the rotor unit has a rotor body and a plurality of blind holes, which are arranged on the outer side of the rotor body; and the ferrite elements are fastened in the blind holes.

[0026] The fastening of the ferrite elements in the blind holes is easily achieved, which makes the system inexpensive to manufacture.

[0027] In a preferred embodiment of the system, the ferrite element is fastened in the blind hole in a form-fitting manner.

[0028] In a preferred embodiment of the system, each blind hole has an internal space having at least one inner surface; each ferrite element has at least one outer surface; and the inner surface and the outer surface are processed to be dimensionally matched, and the inner surface mechanically contacts the outer surface in a form-fitting manner.

[0029] The form fit ensures that the ferrite components will not break even at 20,000 min. -1 Even at higher centrifugal forces, it will not fall off the rotor body. This form fit is very easy to implement and makes the system cost-effective to manufacture.

[0030] In a preferred embodiment of the system, the rotor unit has a coil winding which is applied radially on the outer side of the ferrite element.

[0031] Mounting the coil windings radially on the outside of the ferrite element is also easy to implement and makes the system inexpensive to manufacture.

[0032] In a preferred embodiment of the system, the dipole magnet is made of neodymium-iron-boron.

[0033] The dipole magnets made of neodymium-iron-boron are cheap to purchase, which also makes the system cheap to manufacture.

[0034] In a preferred embodiment of the system, the rotor unit has a rotor body and a groove, which is arranged radially on the outside in the rotor body; and wherein the dipole magnet is fastened in the groove.

[0035] Such a groove can be easily arranged in the rotor body. The dipole magnet fastened in the groove is thus at substantially the same radial distance relative to the axis of rotation as the coil winding, which enables a rotor cover of simple design to cover the dipole magnet and the coil winding. The groove thus contributes to reducing the manufacturing costs of the system.

[0036] In a preferred embodiment of the system, the rotor unit has a rotor cover which is fastened radially on the outside to the rotor unit.

[0037] In a preferred embodiment of the system, the rotor cover is fastened to the rotor unit in a force-fitting manner.

[0038] In a preferred embodiment of the system, the rotor cover is clamped onto the rotor unit.

[0039] In a preferred embodiment of the system, the rotor unit has a coil winding; and the rotor cover clamped onto the rotor unit completely covers the coil winding and the dipole magnet.

[0040] Such a rotor cover protects the dipole magnets and the coil windings from mechanical damage.Such a rotor cover is easy to fasten on the rotor unit and makes the system inexpensive to manufacture.

[0041] In a preferred embodiment of the system, the stator unit is arranged relative to the rotor unit along the axis of rotation with an axial offset tolerance of + / -1.0 mm.

[0042] The axial offset tolerance is the axial degree of freedom when mounting the stator unit next to the rotor unit. Within the range of this axial offset tolerance, the measurement of the magnetic field of the dipole magnet by the magnetic field sensor is not affected. This axial degree of freedom allows the stator unit to be mounted easily and quickly next to the rotor unit.

[0043] In a preferred embodiment of the system, the magnetic field sensor generates a magnetic field signal for each measured magnetic field; wherein the stator unit has an evaluation unit, which executes an evaluation program; wherein the magnetic field sensor transmits the magnetic field signal to the evaluation unit; and wherein the evaluation program counts the magnetic field signals and multiplies them by the distance between the dipole magnets, thereby determining the rotation angle passed by the rotor unit.

[0044] In a preferred embodiment of the system, the strain gauge generates a measurement signal for the detected torque; wherein the rotor unit has a rotor antenna; wherein the strain gauge transmits the measurement signal to the rotor antenna; wherein the stator unit has a stator antenna and an analysis unit, which executes an analysis program; wherein the rotor antenna sends the measurement signal to the stator antenna; wherein the stator antenna transmits the measurement signal received from the rotor antenna to the analysis unit; and wherein the analysis program determines the torque acting on the rotor unit based on the transmitted measurement signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention is described in detail below with reference to the accompanying drawings.

[0046] Figure 1 A view showing a part of a system 1 for detecting torque and rotation angle, which has a rotor unit 10 and a stator unit 20;

[0047] Figure 2 Shown according to Figure 1 A view of a portion of the system 1 along section CC;

[0048] Figure 3 Shown according to Figure 2 An enlarged cross-sectional view of a portion of system 1;

[0049] Figure 4 Shown according to Figure 1 and Figure 2 an enlarged view of a portion of the rotor unit 10; and

[0050] Figure 5 Shown according to Figure 3 FIG. 1 is an enlarged cross-sectional view of a portion of the rotor unit 10 along the section DD.

[0051] The reference numerals are listed as follows:

[0052] 1 System

[0053] 10 Rotor unit

[0054] 11 Secondary Coil

[0055] 100 rotor body

[0056] 1001 Inner surface

[0057] 110 Ferrite components

[0058] 111 Coil winding

[0059] 1101 External surface

[0060] 12 Blind holes

[0061] 120 Blind hole opening

[0062] 121 Interior Space

[0063] 13 Rotor Antenna

[0064] 14 Dipole magnet

[0065] 15 Strain gauge

[0066] 16 grooves

[0067] 17 Rotor cover

[0068] 20 stator unit

[0069] 21 Primary coil

[0070] 22 Stator cover

[0071] 23. Stator antenna

[0072] 24 Magnetic Field Sensor

[0073] 25 Analysis Units

[0074] 30 Radial air gap

[0075] 31 Radial air gap tolerance

[0076] 32 Axial misalignment tolerance

[0077] CC Section

[0078] DD Section

[0079] X rotation axis

[0080] Y horizontal axis

[0081] Z vertical axis DETAILED DESCRIPTION

[0082] Figure 1 A view of a part of a system 1 for detecting torque and rotation angle is shown. Figure 2 according to Figure 1 View along section CC. Figure 3 Shown according to Figure 2 An enlarged cross-sectional view of a portion of system 1. Figure 4 Shown according to Figure 1 and Figure 2 An enlarged view of a portion of the rotor unit 10 .

[0083] Figure 5 Shown according to Figure 3 FIG. 1 is an enlarged cross-sectional view of a portion of the rotor unit 10 along section D. Like reference numerals denote like objects in the drawings.

[0084] The system 1 is shown in a three-dimensional coordinate system comprising a rotational axis X, a horizontal axis Y and a vertical axis Z. These three axes are perpendicular to each other.

[0085] The system 1 has a rotor unit 10 and a stator unit 20 .

[0086] The rotor unit 10 has a hollow cylindrical rotor body 100. The rotor body 100 is made of a mechanically resistant material, such as steel, stainless steel, etc. The rotor unit 10 is configured as a flange and can be fastened to any rotating component by bolting. The design speed of the rotor unit 10 is 20,000 min. -1 And above.

[0087] The stator unit 20 is arranged in a fixed position. The stator unit is separated from the rotor unit 10 by a radial air gap 30 relative to the rotation axis X. The radial air gap 30 is greater than / equal to 2.0 mm and has a radial air gap tolerance 31 of + / -1.5 mm. Independently of this, the stator unit has an axial offset tolerance 32 relative to the rotor unit 10 along the rotation axis X. The axial offset tolerance 32 is + / -1.0 mm.

[0088] The rotor unit 10 has a strain gauge 15. The strain gauge 15 includes a measuring grid and a bridge circuit. When a voltage is applied to the measuring grid, the measuring grid has a resistance. When the measuring grid is stretched or compressed, the resistance changes, and this change in resistance generates a measurement signal in the bridge circuit. The strain gauge 15 dynamically detects the torque and generates up to 10,000 measurement signals per second at a sampling rate of up to 35Ksample. The measurement signal has a resolution of 24Bit. The maximum rated torque detected by the strain gauge 15 is 100Nm and above, and the detection accuracy is less than / equal to 0.05%.

[0089] The rotor unit 10 also has a rotor antenna 13, and the stator unit 20 has a stator antenna 23. The strain gauge 15 and the rotor antenna 13 are electrically connected to each other via an electrical conductor. The strain gauge 15 transmits a measurement signal to the rotor antenna 13 via the electrical conductor. The measurement signal is transmitted contactlessly from the rotor unit 10 to the stator unit 20. To this end, the rotor antenna 13 transmits the measurement signal to the stator antenna 23. Preferably, a transmission frequency of 13.56 MHz is used in the Industrial Science and Medical (ISM) band, and a data transmission rate of up to 1.4 Mbitsec is used. -1 .

[0090] The rotor unit 10 has a secondary coil 11, and the stator unit 20 has a primary coil 21. The primary coil 21 and the secondary coil 11 are inductively coupled to each other. The primary voltage in the primary coil 21 induces a secondary voltage in the secondary coil 11. The stator unit 20 supplies electric energy to the rotor unit 10 through inductive coupling. The inductive coupling of the primary coil 21 and the secondary coil 11 is contactless and occurs within the ISM band with a carrier frequency of 115 kHz to 130 kHz.

[0091] The secondary coil 11 and the strain gauge 15 are electrically connected to each other through an electrical conductor. The secondary coil 11 supplies electric energy to the strain gauge 15 through an electrical conductor. The secondary coil 11 and the rotor antenna 13 are electrically connected to each other through an electrical conductor. The secondary coil 11 supplies electric energy to the rotor antenna 13 through an electrical conductor.

[0092] The rotor unit 10 has a plurality of blind holes 12. These blind holes 12 are arranged radially on the outside in the rotor body 100. The blind holes 12 are arranged on a circumference at a constant radial distance relative to the rotation axis X. Preferably, each blind hole 12 has a blind hole opening 120. The blind hole opening 120 is arranged in the rotor body 100 parallel to the rotation axis X. Each blind hole 12 has a blind hole opening 120 and an inner space 121. The blind hole opening 120 is arranged in the rotor body 100 parallel to the rotation axis X. The inner space 121 can be approached from the outside of the rotor unit 10 through the blind hole opening 120.

[0093] The secondary coil 11 has a plurality of ferrite elements 110. The ferrite elements 110 are manganese-zinc-ferromagnets, nickel-zinc-ferromagnets, etc. Preferably, the ferrite elements 110 are made of material 3C90. The initial magnetic permeability of material 3C90 is greater than / equal to 2000, preferably greater than / equal to 2300. The initial magnetic permeability is determined according to standard DIN IEC 60401 at room temperature of 25°C, with a low current frequency less than / equal to 10 kHz and a low magnetic regulation (magnetischer Aussteuerung) of less than 0.25 mT. The initial magnetic permeability has a variance (Streuung) of + / - 20%. For carrier frequencies in the range of 115 kHz to 130 kHz, material 3C90 has small eddy current losses and at 165 kWm -3 Up to 205kWm -3 The eddy current loss is determined at a room temperature of 25°C and a magnetic regulation of 100 mT. Preferably, the ferrite element 110 is cylindrical. Preferably, each ferrite element 110 has a diameter of 2.0 mm and a length of 7.5 mm. Preferably, the secondary coil 11 has one hundred ferrite elements 110. Preferably, the distance between the ferrite elements 12 is 3.7 mm.

[0094] The ferrite elements 11 are arranged on the circumference of the blind hole 12 at a constant distance from each other. The ferrite elements 110 are fastened in the blind holes 12. One ferrite element 110 is fastened in each blind hole 12. The ferrite element 110 allows access to the inner space 121 through the blind hole opening 120. The fastening of the ferrite element 110 in the blind hole 12 is achieved by a form fit such as latching, a material fit such as bonding, or a force fit such as clamping, or by any combination of form fit, material fit and force fit. Preferably, the inner space 121 has at least one inner surface 1001, and the ferrite element 110 has at least one outer surface 1101. The inner surface 1001 and the outer surface 1101 are processed to match the dimensions, and the inner surface 1001 mechanically contacts the outer surface 1101 in a form fit. Now, if the number of revolutions of the rotor unit 10 is 20000 min -1 When centrifugal force acts on the ferrite element 11 in the case of greater than 100 , the ferrite element 11 cannot fall off from under the rotor body 100 because the above-mentioned shape fit can prevent the ferrite element 11 from moving away from the rotor body 100 .

[0095] The rotor unit 10 has a coil winding 111. The coil winding 111 is arranged radially on the outside of the ferrite element 110. The coil winding 111 is arranged on a circumference at a constant radial distance relative to the rotation axis X. The coil winding 111 is made of a metal wire made of a conductive material such as copper, and the diameter of the metal wire is preferably 0.4 mm.

[0096] The rotor unit 10 has a groove 16. The groove 16 is arranged radially on the outside in the rotor body 100. The groove 16 is arranged on a circumference at a constant radial distance relative to the axis of rotation X.

[0097] The rotor unit 10 has a plurality of dipole magnets 14, the remanence of which is greater than / equal to 1000 mT, preferably greater than / equal to 1400 mT. Preferably, the dipole magnets 14 are made of neodymium-iron-boron. Preferably, the dipole magnets 14 are fastened in the grooves 16. The fastening of the dipole magnets 14 is achieved by means of material matching such as bonding, or by means of force matching such as clamping, or by a combination of material matching and force matching. The dipole magnets 14 are arranged on the circumference of the grooves 16 at a constant distance from each other. Preferably, the rotor unit 10 has seventy-two dipole magnets 14. The distance between the dipole magnets 14 is preferably 5.0 mm. Preferably, the dipole magnets 14 are rectangular. Preferably, the size of each dipole magnet 14 is 3.0x3.0x 4.0 mm 3That is, each dipole magnet 14 has an axial length of 3 mm along the rotation axis X. This axial length of 3 mm enables an axial degree of freedom when the stator unit 20 is mounted next to the rotor unit 10. Since the magnetic field sensor 24 of the stator unit 20 no longer has to be in close proximity to the dipole magnet 14, but has an axial offset tolerance 32 of + / -1.0 mm, the measurement of the magnetic field of the dipole magnet 14 by the magnetic field sensor 24 will not be affected.

[0098] The rotor unit 10 has a rotor cover 17. The rotor cover 17 is fastened to the rotor unit 10 on the outside in the radial direction. The fastening of the rotor cover 17 on the rotor unit 10 is achieved by force fitting such as clamping. The rotor cover 17 is made of a material with high tensile strength and rigidity, such as carbon fiber reinforced plastic (CFK), glass fiber reinforced plastic (GFK), etc. The rotor cover 17 is arranged on a circumference at a constant radial distance relative to the rotation axis X. The rotor cover 17 is strip-shaped. Preferably, the rotor cover 17 is clamped on the rotor unit 10 by elastic deformation. Preferably, the rotor cover 17 clamped on the rotor unit 10 completely covers the coil winding 111 and the dipole magnet 14. Preferably, the radial outer end of the dipole magnet 14 and the radial outer end of the coil winding 111 are substantially the same radial distance relative to the rotation axis X. The rotor cover 17 clamped on the rotor unit 10 thus bears radially and flatly on the outside in direct mechanical contact against the coil winding 111 and in direct mechanical contact against the dipole magnet 14. The rotor cover 17 protects the coil winding 111 and the dipole magnet 14 from mechanical damage.

[0099] The stator unit 20 has a magnetic field sensor 24 that measures the magnetic field of the dipole magnet 14 when the rotor unit 10 rotates. The magnetic field sensor 24 is a Hall sensor, a magnetoresistive sensor, etc. The magnetic field sensor 24 generates a magnetic field signal for each magnetic field measured. Preferably, the magnetic field signal is a digital signal.

[0100] The stator unit 20 has an analysis unit 25. The analysis unit 25 is a circuit having at least one data processor and at least one data memory. The analysis unit 25 has at least one analysis program. The analysis program is stored in the data memory and can be loaded from the data memory to the data processor. The analysis unit 25 executes the analysis program loaded into the data processor.

[0101] The stator antenna 23 and the analysis unit 25 are electrically connected to each other via an electrical conductor. The stator antenna 23 transmits the measurement signal received from the rotor antenna 13 to the analysis unit 25 via the electrical conductor. The analysis program loaded into the data processor determines the torque acting on the rotor unit 10 based on the transmitted measurement signal.

[0102] The magnetic field sensor 24 and the analysis unit 25 are electrically connected to each other via an electrical conductor. The magnetic field sensor 24 transmits a magnetic field signal to the analysis unit 25 via the electrical conductor. The analysis program loaded into the data processor counts the transmitted magnetic field signals. The distance values ​​between the dipole magnets 14 are stored in a data memory. The analysis program loaded into the data processor reads the distance values ​​between the dipole magnets 14 from the data memory and multiplies it by the number of counted magnetic field signals to determine the rotation angle passed by the rotor unit 10.

[0103] System 1 can be used in a variety of industrial measurement technology applications. In test bench technology, system 1 can be used to detect torques and rotation angles. Even in machining of workpieces, system 1 can be used to detect torques and rotation angles on rotating parts.

Claims

1. A system (1) for detecting torque and rotation angle, comprising: a rotor unit (10) rotatable about an axis of rotation (X); a stator unit (20) which is arranged in a stationary manner and is separated from the rotor unit (10) by a radial air gap (30) relative to the rotation axis (X); in, The rotor unit (10) has a strain gauge (15) which detects a torque acting on the rotor unit (10); The rotor unit (10) has a plurality of dipole magnets (14), which are arranged spaced apart from each other; The stator unit (20) has a magnetic field sensor (24), which measures the magnetic field of the dipole magnet (14) when the rotor unit (10) rotates; wherein the stator unit (20) has a primary coil (21), and the rotor unit (10) has a secondary coil (11); wherein the primary voltage in the primary coil (21) induces a secondary voltage in the secondary coil (11); The invention is characterized in that each of the dipole magnets (14) has a residual magnetism greater than / equal to 1000 mT; and the secondary coil (11) has a plurality of ferrite elements (110).

2. The system (1) according to claim 1, characterized in that Each of the dipole magnets (14) has a remanence greater than or equal to 1400 mT.

3. The system (1) according to claim 1, characterized in that The radial air gap (30) is greater than / equal to 2.0 mm and has a radial air gap tolerance (31) of + / -1.5 mm.

4. The system (1) according to claim 1, characterized in that The rotor unit (10) has a rotor body (100) and a plurality of blind holes (12), wherein the blind holes (12) are arranged on the outer side of the rotor body (100); and the ferrite elements (110) are fastened in the blind holes (12).

5. The system (1) according to claim 4, characterized in that The ferrite element (110) is fastened in the blind hole (12) in a form-fitting manner.

6. The system (1) according to claim 5, characterized in that Each blind hole (12) has an internal space (121), and the internal space (121) has at least one inner surface (1001); each ferrite element (110) has at least one outer surface (1101); and the inner surface (1001) and the outer surface (1101) are processed to match their dimensions, and the inner surface (1001) mechanically contacts the outer surface (1101) in a shape-fitting manner.

7. The system (1) according to any one of claims 1 to 6, characterized in that The rotor unit (10) has a coil winding (111) which is mounted radially on the outside of the ferrite element (110).

8. The system (1) according to any one of claims 1 to 6, characterized in that The dipole magnet (14) is made of neodymium-iron-boron.

9. The system (1) according to any one of claims 1 to 6, characterized in that The rotor unit (10) has a rotor body (100) and a groove (16) which is arranged radially outside in the rotor body (100); and the dipole magnet (14) is fastened in the groove (16).

10. The system (1) according to any one of claims 1 to 6, characterized in that The rotor unit (10) has a rotor cover (17) which is fastened radially on the outside of the rotor unit (10).

11. The system (1) according to claim 10, characterized in that The rotor cover (17) is fastened to the rotor unit (10) in a force-fitting manner.

12. The system (1) according to claim 10, characterized in that The rotor cover (17) is clamped onto the rotor unit (10).

13. The system (1) according to claim 12, characterized in that The rotor unit (10) has a coil winding (111); and a rotor cover (17) clamped on the rotor unit (10) completely covers the coil winding (111) and the dipole magnet (14).

14. The system (1) according to any one of claims 1 to 6, characterized in that The stator unit (20) is arranged relative to the rotor unit (10) along the rotation axis (X) with an axial offset tolerance (32) of + / -1.0 mm.

15. System (1) according to any one of claims 1 to 6, characterized in that The magnetic field sensor (24) generates a magnetic field signal for each magnetic field measured; the stator unit (20) has an analysis unit (25) which executes an analysis program; the magnetic field sensor (24) transmits the magnetic field signal to the analysis unit (25); and the analysis program counts the magnetic field signal and multiplies it by the distance between the dipole magnets (14), thereby determining the rotation angle passed by the rotor unit (10).

16. The system (1) according to any one of claims 1 to 6, characterized in that The strain gauge (15) generates a measurement signal for the detected torque; the rotor unit (10) has a rotor antenna (13); the strain gauge (15) transmits the measurement signal to the rotor antenna (13); the stator unit (20) has a stator antenna (23) and an analysis unit (25), and the analysis unit (25) executes an analysis program; the rotor antenna (13) sends the measurement signal to the stator antenna (23); the stator antenna (23) transmits the measurement signal received from the rotor antenna (13) to the analysis unit (25); and the analysis program determines the torque acting on the rotor unit (10) based on the transmitted measurement signal.

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