RU2615612C2 - Contactless true dual axis shaft encoder - Google Patents

Abstract

FIELD: physics, measurement equipment.

SUBSTANCE: invention refers to measurement equipment, namely to the field of contactless measurement of the shaft rotation angle. Contactless true dual axis shaft encoder uses a magnetic system based on a small dipole diametrically magnetized magnet, accomplishing angular movement with two freedom degrees in the working plane parallel to the front surface of the Hall programmable dual axis encoder with integrated magnetic concentrating (IMC) discs, performing magnetic field physical conversion in the working plane into perpendicular, to which the Hall encoder with IMC is truly sensitive, also other types of sensors are used which are highly sensitive only to the magnetic field components on the working (XY) plane and completely or light sensitive to the magnetic field vertical component (Z), and the integral component of the true dual axis encoder can be mounted on either side of the board, and the insert, being the central structural component or element of the housing part, is rigidly connected to the housing and ensures accurate positioning in the stator housing relative to each other, dipole magnet rotor and the integral component of the dual axis magnetosensitive sensor with the optimum working distance between them. Moreover, the shaft encoder uses dipole magnet magnetized parallel to the plane in which the rotor performs working angular movement with two freedom degrees, there is also an integral true dual axis magnetosensitive sensor (encoder) with sine-cosine primary output signals included in the signal processing circuit, and an excess integral sensor that combines two magnetosensitive elements in one integrated housing.

EFFECT: invention provides for an increase in sensitivity, accuracy and reliability of the shaft encoder.

10 cl, 5 dwg

Description

The invention relates to measuring technique, namely, to the field of non-contact measurements of the angle of rotation of the shaft by means of a magnetic system consisting of a dipole magnetic rotor and a non-contact biaxial sensor (encoder) with sine-cosine primary output signals of the magnetic field, by which the rotation angle of the magnet is calculated. The present invention to a greater extent involves the use of sensors based on the TMP (tunneling magnetoresistive) effect and can be used partially or completely for sensors based on the GMP (giant magnetoresistive) or AMP (anisotropic magnetic resistive effect, Hall sensors or other types of sensors. Technical applications include car electronics (sensors of the angular position of the throttle, pedal, steering wheel angle), switching brushless motors, joysticks, measuring t eye, electronic compasses and other similar applications in various industries.

At the moment, in a magnetic system based on a dipole rotor, pseudo-two-axis magnetic field sensors with planar Hall elements are widely used, which are physically sensitive to a magnetic field perpendicular to the surface of the sensitive elements and the surface of the microcircuit, but their sensitivity to a magnetic field parallel to the surface is achieved in various ways microcircuit case.

A similar device is described in patent No. 2301399 dated 05.05.2005 (published 2007.06.20) “Non-contact pedal position sensor”.

The technical result achieved by this invention is to increase the accuracy, sensitivity, reliability, expand the range of measured angles to almost 360-degree range, increase interface capabilities, improve signal stability, develop adaptive features to specific working conditions.

The pedal position sensor disclosed in the description contains a rotor with a magnet, making a circular motion relative to the stationary stator in an angular range of up to 360 °. The stator is a programmable integrated circuit of a two-axis angular encoder with an integrated cross-shaped array of sensitive elements. In fact, the device reveals a highly integrated sensor that contains planar Hall elements that are sensitive to a perpendicular magnetic field that changes sinusoidally with a circular motion of the magnet.

The planar Hall elements are flat elements that are located in the microcircuit housing parallel to its surface and are sensitive to a magnetic field perpendicular to the surface of the microcircuit housing (in the direction of the Z-axis). When an array of two, four, or four times four of the number of planar Hall elements with a phase shift of 90 ° is located for a given angle of rotation in the XY plane, this array is capable of generating sine and cosine voltage signals proportional to the magnitude of the magnetic field along the Z axis. Using sine-cosine signals, it is possible to first calculate the arc tangent, and then the most unique value of the angle in the XY plane in the range up to 360 ° - using the CoRDiC algorithm. The angular information obtained through the arc tangent function is compensated for magnetic field variations (due to changes in the air gap, effects of temperature and aging).

But in reality, due to the true sensitivity of Hall sensors to a perpendicular field, static and dynamic gap measurements, especially together with eccentricity, significantly upset the magnetic system. Slopes create biases of the sine-cosine signals and emulate inconsistencies in the sensitivities of planar elements that additionally suffer from non-orthogonality of signals and intrinsic signal non-linearity - as a result, the angular error will be higher, that is, the accuracy is actually much worse than the calculated one (0.5-1 ° in the range 360 °) and amounts to several angular degrees.

This device is characterized by limited sensitivity due to the measuring principle of the Hall effect, carried out by means of planar elements. Parallel field components in a given magnetic system directly in the XY plane can give scalar values of sine-cosine signals that are larger in amplitude and magnitude than components of a perpendicular magnetic field.

The assembly process of the analogue is characterized by a lack of manufacturability. This device uses a chip programmable only once in the manufacture of the sensor. In the description of the analogue it is disclosed that the correspondence of mechanical and magnetic zero is set programmatically and they may not coincide. But upon the fact of assembly, magnetic and mechanical errors arise, which in this device for serial production conditions are compensated not only by software, but also by hardware, namely, a certain correspondence between the magnetization orientation of the magnet (light axis) or magnetic zero relative to the microcircuit is provided for all sensors, provided before or after programming the zero position by aligning the diametrically magnetized magnet in the sleeve with screwdriver slots showing the orientation magnetic field, and then the magnet already in this sleeve in the grooves is installed in the mounting sleeve of the rotor with other orienting elements. Although this stage provides certain advantages, for example, it allows the use of pre-programmed microcircuits even before assembly, but its presence burdens the process. The use of technological conclusions for programming after assembly, which are sealed off before the final installation of the cover, is also an unnecessary operation.

Subsequently, the technical level allowed the use of other microcircuits, which make it possible not only once but repeatedly to program the zero position, which also does not have to correspond to the physical zero of the field or the easy axis of magnetization of the magnet. If programming is carried out after assembly, and not before assembly, the need for orienting elements disappears. In addition, the level of technological development allowed the appearance of microchips programmed only by means of functional, without additional technological, conclusions.

The analogue does not reveal essential features to ensure full three-dimensional fixation of the required mutual placement of the microcircuit, magnet and other parts - so that all positioning tolerances are observed and vertical rotor movements, reeling, eccentricity, friction and runout of parts are avoided. On top of the rotor assembly, a part is installed that acts as a limiter of the rotor travel mainly only vertically and only partially in the working plane. The main function of this part is to provide a working air gap in the magnetic system.

The analog device is characterized by a small working gap between the microcircuit and the magnet no higher than 2 mm. This device provides a working magnetic field of 45-75 mT with a standard working distance (air gap) of the order of 0.5-1 (no more than 2) mm between the sensor with planar Hall elements and a magnet with a diameter of 6 mm and a height of 2.5 mm, selection which is the preferred option. With such a small working distance, physical destruction of the microcircuit by a movable magnet is especially dangerous, protection from which complicates the design of a component that acts as a limiter of the rotor's travel. An increase in the working distance (gap) will lead to a deterioration in the working sensitivity of the sensor, while also increasing spurious sensitivity to undesirable magnetic and mechanical displacements in 3D space. The result will be a general decrease in accuracy. Large working distances will make the design of the analogue more cumbersome. Also, increasing the working distance between the magnet and the microcircuit will require large magnets and magnetization magnets to achieve the required working field values.

These disadvantages are shown by the following analogue of the present invention, which is the “Non-contact encoder of the angular position of the shaft” disclosed in patent No. 2262659 dated 10.26.2004 (publication date 2005.10.20). The invention describes a throttle position sensor of automobile engines.

This device has much in common with the device disclosed in patent No. 2301399. The device comprises a base in the form of a glass with a through hole in the bottom, as well as an insert with a through hole made in a plane parallel to the plane of the bottom of the base. Similar details are described in patent No. 2301399 as a sensor housing and a cover cap. There is a magnet holder made in the form of a body of revolution, a magnetic system, a printed circuit board with a magnetoelectric transducer placed on it, a connector electrically connected to the printed circuit board, and a cover. All these details are also present in patent No. 2301399: the microcircuit is sealed on the board, the same magnetic system is used, and the analog of the magnet holder is the mounting sleeve in patent No. 2301399.

This device uses other features disclosed in the patent analogue No. 2301399. In the patent of the analogue No. 2262659, one end of the rotor is introduced into the hole of the base, and the other, intended for attaching to it a magnetic system, is introduced with the possibility of rotation in the hole of the insert. In this case, the magnet holder in the part located in the cavity of the base is made with two shoulders, one of which abuts against the bottom of the base through the elastic element, the other into the insertion plane. The printed circuit board is installed in the cavity of the cover so that the magnetoelectric transducer placed on it is located in the range of the magnetic system.

Differences from patent No. 2301399 are that the microcircuit in patent No. 2262659 is sealed on the other side of the board, which increases the working distance between the microcircuit and the magnet, which, in turn, requires the use of more highly sensitive microcircuits than the planar pseudo-two-axis ones known at the time of publication of the patent Hall sensors, and the use of larger and stronger magnetization magnets - otherwise the functional characteristics of the sensor deteriorate.

This device is practically inoperative with standard pseudo-two-axis encoders with planar Hall elements and small magnets of the recommended sizes with a diameter of 6 and a height of 2.5 mm. The fact is that the minimum board thickness is usually 1 mm (with a standard working distance for Hall encoder chips with planar elements of the order of 0.5-1 mm), and chip manufacturers place sensitive elements closer to the front side, not the back. A minimum gap between the magnet and the circuit board is also required to avoid friction and beating of the magnet against the circuit board. In fact, the working distance between the microcircuit and the magnet in this device is at least 2 mm, which is two times higher than recommended to ensure the operability of the planar Hall sensor.

The increase in working distances demonstrated in analogue patent No. 2301399 not only imposes restrictions on the component base and increases the size and requirements for magnetization of magnets, but also negatively affects the exposure of the device to undesirable magnetic and mechanical displacements in 3D space, which also results in a general decrease in the level accuracy. Regardless of the technology used, any type of sensor is sensitive to any static displacement of the magnetic system relative to the center of the magnetically sensitive element and the eccentricity. Hall sensors with planar elements are sensitive to vertical displacements and inclinations, which is aggravated by the simultaneous action of radial static and dynamic displacements. This device does not provide any special measures for centering the magnet relative to the center of the sensitive array of Hall elements, reducing eccentricity and sensitivity to vertical displacements and inclinations.

It is stated that the invention allows to reduce the complexity and reduce the cost of manufacturing the sensor in serial production, which is not true, since with serial production it is extremely important to ensure the possibility of programming the device after assembly to compensate for magnetic, mechanical tolerances and operating conditions. In this device, the insert with its plane with the hole separates the lid cavity, in which the printed circuit board is located, from the base cavity through which the magnet holder passes, which is not required by itself. The main purpose of this part is to ensure the positioning of the microcircuit and magnet at the required working distance, and the larger the gap, the thicker this part.

At the time this patent was published in 2005, another commercially available component base of highly integrated and programmable Hall sensors with IMC based on Triaxis Melexis technology, vertical Hall sensors (technology from the Fraunhofer Institute licensed by ams and Micronas), fully integrated by AMP, was not yet known. sensors (NXP) and GMR sensors (Infineon) and especially TMP sensors.

The use of AMR (anisotropic magnetoresistive) and GMR (giant magnetoresistive) angle sensors as part of automotive angle sensors is partially known from the prior art (article by S. S. Sysoeva “XMR microsystems - an alternative to Hall sensors in motion and current monitoring systems” in the journal “ Components and Technologies ”No. 4 for 2012).

The article describes examples of the NXP AMR component base. It is known that AMR sensors usually work well with weak fields when they reach a working field above a certain value of the order of 25 kA / m), although the presented designs show either small gaps and mounting from the side of the board close to the magnet, or general mounting methods without using a board , and also show the use of large-sized and magnetized magnets with small gaps.

For example, the use of NXP AMP sensors is disclosed in US Pat. No. 7,230,419 to Rotary position sensor, announced in June 2005, and published in June 2007, where the design shows mounting on the side of the board close to the magnet.

For high-level GMD sensors of Infineon integration, the article shows the fact of the possible flexible installation of these components from any, mainly from the upper side of the board on which the sensor is mounted, since the high sensitivity of the sensor requires its removal from a standard magnet.

The above components are highly sensitive to the magnetic field (and, with the exception of Triaxis Melexis technology, it is sensitive to parallel XY field components), sufficient to work at such working distances - of the order of 2-5 mm and above, and many of them have functions of multiple reprogramming the transfer characteristic and calibration factors in the EEPROM. But the analogues patents and design descriptions in the article did not disclose the use of these capabilities for flexible mounting of the sensor on either side of the board, flexible selection of components, varying the size of magnets, programming of the main parameters, including sensitivity, compensation of assembly tolerances, temperature and time drifts.

The prototype is the device disclosed in patent No. 2317522 "Programmable proximity sensor of angular position with a linear angular range within 360 °" from 01/30/2006 (publication date 02/20/2008). In this device, the sensor stator includes the most relevant at that time chip of the so-called 3D angular Hall encoder, the technology of which is characterized by increased sensitivity of planar elements to parallel field components in the XY plane due to integrated magnetically concentrating (IMC) disks in such microcircuits. The use of the Hall encoder with IMC provides high sensitivity to the working 2D field in the XY plane of 20-70 mT. Sensor ICs include EEPROM reprogrammable memory. The programming of the format, calibration points, displacement, direction of rotation, sensitivity (gain) of the analog or PWM transfer characteristics, temperature sensitivity, as well as other calibration parameters is carried out after assembly of the device.

The use of the 3D Hall encoder gives high sensitivity to the working 2D field in the XY plane up to 20 mT down and allows higher working distances. The use of such a microcircuit gives greater flexibility in the placement of the magnet relative to the stator, allows even simpler designs and completely non-contact sensors in which the rotor and stator may not be in contact with each other (as in patent No. 2312363 dated January 31, 2006 "Non-contact programmable absolute angle position sensor in 360 ° range ”, its publication date 10.12.2007), the ability to measure angles in the range 0 ... 360 ° without“ dead zones ”with the absence of, if necessary, limiting elements (stops and protrusions) in the rotor structures and with Ator.

But there is still sensitivity to displacements in the Z-axis, as a result of which working gaps, vertical positioning tolerances, inclinations and other factors still limit the sensitivity and accuracy of the sensor and the possibility of its adaptation to specific working conditions.

To achieve greater linearity and accuracy, it is still recommended that the operating distances that are optimal in this assembly be maintained - so that the horizontal flux density remains in the range of 20-70 mT (45 mT ± 25 mT) at the IP level. Magnets should be selected based on the axial distance (gap) corresponding to the given working field. Small magnets with a diameter of 6 mm and a height of 2.5 mm can be used with working distances of the order of 0.5-5 mm, but large gaps are possible only if a small eccentricity is ensured. To compensate for the eccentricity at large working distances, large magnets are used.

 Difficult is the problem of increasing accuracy in the presence of a large eccentricity. According to Melexis, the magnet should be 10 times larger than the maximum eccentricity to achieve non-linearity of 1 °, and 20 more to achieve non-linearity of 0.3 °.

Large magnets have the following disadvantages:

• Inhomogeneity (degrading accuracy).

• Strong fields require large working distances (the working field for sensors must be kept up to 70 mT).

• Larger magnets have a higher cost.

Too small a distance increases the risk of electrical or magnetic saturation. The influence of imperfections in the magnetic material on accuracy is also enhanced in this case.

Therefore, the prototype recommended the use of magnets of only small sizes, providing a working magnetic field, and the working distance is limited to the optimal value.

These are not truly biaxial, but highly biaxial or 3D sensors, since they are actually sensitive not to the parallel field, but to the perpendicular, including the intrinsic components of the perpendicular field, and obtained by converting parallel components to perpendicular through the IMC.

In the MLX90316, using the ATAN function (VY / VX) to calculate the angle by viewing tables (without using the CoRDiC algorithm) allows the angle information to self-compensate for variations in the magnetic field (due to changes in the air gap, effects of temperature and aging) for both sine-cosine signals .

But in reality, due to the presence of the sensitivity of the Hall sensors to the perpendicular field, the static and dynamic gap measurements, especially together with the eccentricity, upset the magnetic system. Slopes create biases of the VY and VX signals and emulate inconsistencies in the sensitivities of planar elements, which additionally suffer from non-orthogonality of signals and intrinsic signal non-linearity - as a result, the angular error will be higher.

In the prototype device, by introducing a structural component restricting the rotor stroke, the working gap is optimized and the sensor is mechanically protected, the magnetic system is partially centered, the rotation eccentricity and the rotor inclination relative to the housing are reduced, but more complete measures are required to reduce the undesirable vertical sensitivity of the sensor, aggravated by insufficient centering the magnetic system and the presence / sensitivity of the eccentricity of rotation, as well as rotor slopes relative to the center of the sensor.

The disadvantages of the prototype and analogues also include insufficient reliability. The failure of a conventional microcircuit leads to the complete inoperability of any of the above sensors, which threatens the so-called automotive functional safety, the provision of which is updated by the ISO26262 standard. To comply with this standard, automotive sensor manufacturers integrate two integrated components, and chip manufacturers develop components with two sensors or crystals in an integrated housing to reduce the likelihood of failure in the event of failure of one of them.

The objectives of the invention are to further increase the sensitivity of the sensor to a working parallel magnetic field, increase resolution and accuracy, reduce unwanted sensitivity to vertical and horizontal displacements, increase the flexibility of mechanical placement in the 3D space of the sensor relative to the magnet, circuit board, housing and parts of the stator and rotor, further miniaturization simplifying the design and installation, as well as reducing energy consumption, increasing reliability and functional safety.

The tasks are solved by the fact that in a non-contact true biaxial shaft angle sensor based on the prototype design using a magnetic system based on a small dipole diametrically magnetized magnet that performs angular motion with two degrees of freedom in the working plane parallel to the front surface of the programmable two-axis Hall encoder with integrated magnetically concentrating (IMC) disks that perform physical conversion of the magnetic field in the working plane into perpendicular e, which truly sensitive Hall sensor with IMC, other types of sensors are used, only highly sensitive to magnetic field components in the working (XY) plane and relatively or completely insensitive to the vertical component (Z) of the magnetic field.

These components are all magnetoresistive sensors based on the so-called XMR effects - AMR, GMR, TMP, KMP (colossal magnetoresistive), EMR (extraordinary magnetoresistive) and Hall sensors with vertical (non-planar) elements that are sensitive only to magnetic field components in the XY plane . Among all commercial magnetoresistive components currently available, MDT TMP sensors have the highest sensitivity, show the greatest change in angular resistance, the highest level of the primary signal without the need for amplification, are characterized by the ability to detect weak magnetic fields, high temperature stability, and a wide range of available working distances resistant to mechanical and magnetic displacements. These and their other advantages in the aggregate led to the preferred choice of precisely these components for the development of basic variants of the claimed device.

The above sensors are sensitive specifically to the components of the magnetic field in the XY plane. AMR, GMR, TMP and other MR sensors used in this device are sensitive to direction, but not to the magnitude of the magnetic field in the XY plane, and vertical Hall sensors are sensitive to the absolute values of the magnetic field components in the XY plane. But all of them, by definition, are completely insensitive to the vertical component (Z) of the magnetic field. All these types of sensors allow flexible selection of magnets of various geometries and magnetizations, although they still have some sensitivity to tilting and eccentricity. Sensitivity to eccentricity is a direct consequence of their true 2D sensitivity - a sensor that is highly sensitive in the XY plane is, by definition, sensitive to any undesirable displacements in this plane, including the off-center placement of the microcircuit and magnet, eccentricity, inclination of the microcircuit or magnet.

The integral component of a true biaxial sensor can be mounted on either side of the board, which is determined by the requirement to ensure the optimum working distance between the microcircuit and the magnet in the magnetic system and other considerations. Two components of a true biaxial sensor can be mounted simultaneously on both sides of the board to ensure the working distance between each microcircuit and the magnet in the magnetic system, which allows you to shoot two sine-cosine or angular signals at the same time or one of them in case of failure of one of the sensors ( redundant system).

In the inventive non-contact true biaxial shaft angle sensor, the central structural component or element of the housing part — the insert — is rigidly connected to the housing and ensures accurate positioning of the dipole magnetic rotor and the integral component of the biaxial magnetosensitive sensor with an optimal working distance between them in the stator housing, limits rotor movement to two degrees of freedom in the working plane, without axial and radial displacements, eccentricity, on clones through their structural elements and surfaces, the accuracy of which is ensured in the production of parts. To achieve the optimal working distance (gap) between the microcircuit and the magnet in the base design, a central circular hole is made in the insert, at the same time ensuring the restriction of undesirable rotor movements vertically and horizontally, as well as the optimal placement of the microcircuit or magnet in it.

In the inventive non-contact true biaxial shaft angle sensor, a dipole magnet is used, magnetized parallel to the plane in which the rotor makes a working angular movement with two degrees of freedom. The magnet has any of the following forms: a solid cylinder, a disk, a cylinder or a disk with a central through hole or a through hole (groove) on the side adjacent to the magnetosensitive sensor when it is installed in a magnet holder, a ring-shaped magnet (with a wide through hole), a rectangular magnet box or cube.

In the inventive non-contact true biaxial shaft rotation angle sensor, an integral true biaxial magnetosensitive sensor (encoder) with sine-cosine primary output signals is included in the signal processing circuit, which generates an output signal proportional to the rotation angle with a zero or reference value, relative to which the rotation angle is calculated. Since programming after assembling the output transfer characteristic and calibration coefficients gives the advantage of compensating magnetic, mechanical tolerances, temperature coefficients and other parameters to adapt to the conditions of assembly and operation, the processing circuit also includes a reprogrammable EEPROM memory for such programming.

Depending on the level of integration of the integrated component used in the non-contact true two-axis shaft angle sensor, the signal processing circuit can be integrated into the integrated module of the true two-axis magnetosensitive sensor (encoder) or into the integrated truly two-axis magnetically sensitive sensor (encoder), which is an integrated sensor microcircuit.

A non-contact redundant true biaxial shaft angle sensor may include a redundant integral sensor that combines two magnetically sensitive elements of one or different types in one integrated housing, which produce two primary sine-cosine output signals each, for these primary signals two external or integrated signal processing circuits form a double output signal proportional to the angle of rotation.

In a non-contact redundant true two-axis shaft angle sensor, simultaneously two integral sensors of one or different (including redundant) types in the stator housing of the device can be positioned on both sides of the printed circuit board and generate at least two primary sine-cosine output signals each, for which two external or integrated signal processing circuits form at least a double output signal proportional to the angle of rotation.

A non-contact true two-axis shaft angle sensor, in which at least one integral truly two-axis magnetically sensitive sensor (encoder) with sine-cosine primary output signals, is included in the signal processing circuit with a microcontroller that performs all the signal processing functions and allows the connection of other types of sensors, It is a non-contact, true biaxial sensor unit for measuring the angle of rotation of the shaft.

The non-contact true biaxial shaft angle sensor according to the claimed invention is shown in FIG. 1-5.

In FIG. 1 shows a General view of the inventive sensor, in FIG. 2 is a variant of the claimed device in section with the location of the integrated sensor on the reverse side of the board closest to the magnet (as in the prototype device), in FIG. 3 is a sectional view of an embodiment of the device with an integrated sensor located on the upper side of the board; FIG. 4 - redundant design with two sensors mounted simultaneously on both sides of the board. In FIG. 5 shows a collapsible view of the device.

The non-contact true two-axis shaft angle sensor consists of two main assembly units - the stator 1 and rotor 2. The assembly unit of the stator 1 includes the assembly unit 3 of the housing with contacts, consisting of the housing 5 itself with the contacts of the connector 6 pressed into it. The main functional component of the stator 1 is an electronic unit 4, combining at least one integral component of a true biaxial magnetosensitive sensor 7 or 8, mounted on the board 9 by surface mounting, as well as a friend e discrete components or elements of the electrical circuit principle of the device.

The rotor 2 consists of a magnet 10 mounted on the side of the sensor 7 in the rotating magnet holder 11.

The device also includes an elastic element - a torsion return spring 12. After installing the magnet 10 in the magnet holder 11, the assembly 2 is assembled with the spring 12 and then installed in the stator housing 3 with the free end of the spring 12 fixed for torsion during rotation of the rotor 2. After installation rotor 2 with a spring 12 in the housing 3 is first installed central structural insert 13, and then the electronic unit 4 - board 9 with a sensor 7 or 8 and other components and elements.

The contacts 6 of the electrical connector of the sensor housing are sealed on the board 9 after it is mounted in the housing 3. After assembly, the device is closed by a cover 14.

The board 9 is installed in the housing 3 with its landing surface 9 A on the housing surface (flat faces) 5 A by means of a fusible structural housing elements (pins) 5 a installed in the holes of the board 9 a. In this case, the board 9 is centered relative to the structural part - the insert 13 installed in the stator housing 1 by a seating surface of 13 B on the housing surface of 5 B by means of 13 b insert elements and 5 b housing elements (holes) or individual mounting components 15. The 9 board and insert 13 can be installed using different or the same methods of rigidly fixing these parts in the housing, the choice of which is not fundamental and allows various options (press-fit, fit onto adhesive, heat shrink or heat seal of the threaded connection). The board 9 and the insert 13 can be installed by means of fasteners 5 a and 15, which can be different, identical or common for both parts (for example, an installation option is possible when the surface 9 A of the board 9 is installed not only on the case surface 5 A , but also directly on the upper surface of the insert 13 A).

Contactless true biaxial shaft angle sensor operates as follows.

Rotor 2 performs a working angular movement in the XY plane in an angular range up to 360 ° inclusive with two degrees of freedom (clockwise and counterclockwise). To limit the angular range to less than 360 ° in the housing 5 there are stops 5 V, and in the part of the magnet holder 11 with the same purpose protrusions 11 in. The bottom surface of the 11 V magnet holder with the protrusions 11 V is associated with the corresponding inner surface of 5 V with stops 5 V. The insert 13 provides an optimal air gap in the system between the microcircuit 7 and 8 and the magnet 10 and limits the vertical movement of the rotor 2 along the Z axis by means of the same seating surface 13 B, mating with the corresponding surface 11 B of the magnet holder 11.

TMP components not only allow the replacement of Hall sensors in the design of the prototype, but also due to their own high sensitivity to parallel components of the magnetic field, large working distances are of the order of 2-5 mm and higher, with the same small magnet with a diameter of 6 mm and a height of 2, 5 mm, which is the preferred choice in the prototype device. TMP components allow more flexible mechanical placement in the 3D space of the sensor 7 and 8 relative to the magnet 10 - on either side of the board 9. The use of TMP components demonstrates further miniaturization, the possibility of flexible selection of magnets of any shape and magnetization along with varying working distances, further simplifying the design and installation .

Since TMP components are truly biaxial components, a reduction in undesirable sensitivity to vertical displacements and tilts of magnet 10 relative to sensor 7 and 8 is achieved at the physical level.

Since TMP components are truly biaxial sensors that have not only high working, but also parasitic sensitivity in the XY plane, special measures can be taken in designs to reduce unwanted horizontal displacements of the magnetic system, the eccentricity of the rotor and the slope of the rotor relative to the center of the sensor. A small eccentricity allows the use of smaller magnets, and a larger eccentricity can be compensated for by the use of magnets larger in size and magnetization.

The Central through hole 13 g in the insert 13 is centered relative to the microcircuit 7 and 8 and forms a cylinder or a truncated cone with an inner surface of 13 G, which allows the angular movement of the rotor in the XY plane with two angular degrees of freedom. The eccentricity and unwanted radial displacements of the magnet holder 11 with the magnet 10 relative to the sensor 7 and 8 are reduced by selecting the correspondence of the sizes — the height and outer diameters of the elements 11 a and 11 b of the magnet holder 11, the height and diameter of the hole 13 g (the area of the inner surface is 13 G), and the height of the case surface 5 B for landing the bottom surface 13 B through the elements of the housing 5 b and insert elements 13 b. To increase the height of the hole 13 g in the insert 13 can be used the same cylindrical protrusions 13 in, borrowed from the design of the prototype.

The microcircuit 7 or 8 or magnet 10 in the design of the inventive device is very small, which allows not only their flexible placement in the housing 5, but also the flexible modification of their mutual vertical positioning due to the presence of a 13 g round hole that allows varying the working distance (gap) as due to changes in the vertical position of the magnet 10, and due to the possibility of vertical positioning within this hole of the sensor 7.

In addition, the use of TMP and similar components in the design of throttle position sensors demonstrates other advantages - reduced energy consumption, increased reliability and functional safety. The failure of a conventional microcircuit leads to the complete inoperability of any sensor, which threatens the so-called automotive functional safety, the provision of which is updated by the ISO26262 standard. The considered designs easily allow the placement of two TMP sensors simultaneously on both sides of the board and the creation of the so-called redundant measuring system.

A redundant configuration based on two sensors 7 and 8, simultaneously mounted on both sides of the board 9, is shown in FIG. four.

In the inventive device, it is preferable to use components 7 and 8 of the highest possible integration level - a system-on-a-chip level or a system in a housing, sensors programmable in the EEPROM, with DSP functions via microcontrollers, which also allow the connection of other types of sensors - temperature, MEMS inertia sensors and turning the device from conventional angle sensor in the microcontroller sensor assembly. In the absence of an accessible component base of highly integrated circuits, such a processing scheme can be performed external to the sensor 7 (sensors 7 and 8) and placed on the board 9.

In a redundant configuration, any of the sensors 7 and 8 can have the highest possible level of integration, and can also be a redundant component, which will provide even higher reliability and functional safety.

Since TMP components, in particular, have reduced power consumption, in the case of their application, the energy consumption of the entire device is reduced, they also do not require amplification and additional components, and therefore their accuracy does not depend on noise due to amplification. Other types of sensors (AMR, GMR, vertical Hall sensors), although they cannot provide the same reduction in energy consumption, they are quite compatible with the current power conditions in the car, and due to the level of integration they achieved, they also do not require many additional circuit components.

Compared with the prototype, the inventive non-contact true biaxial shaft angle sensor is characterized by increased sensitivity specifically to the working parallel magnetic field, which is achieved by using an integral component based on any of the effects that are sensitive only to parallel field components - TMP (preferably), AMR, GMR, vertical Hall sensors or other types of true biaxial sensors. The device allows a wide range of suitable component base. Through the use of a more highly sensitive component, an increase in resolution and measuring accuracy is achieved, in ideal conditions equivalent to resolution. Since the device uses special, including constructive, measures to reduce unwanted sensitivity to vertical, horizontal displacements, inclinations, the operating conditions of the sensor approach ideal and, therefore, the accuracy increases precisely in real operating conditions. The inventive sensor demonstrates a general increase in the flexibility of mutual mechanical placement in the 3D sensor relative to the magnet, circuit board, housing and parts of the stator and rotor, further miniaturization, simplification of design and installation, and a number of private advantages when using individual components, including reducing power consumption of TMP components.

The use of redundant components and redundant configurations demonstrate the benefits of increased reliability and functional safety. The claimed device allows flexible modification of structures from one to another.

The technical result achieved by this invention is to simultaneously achieve all of the above advantageous features, the most important of which are increased sensitivity, accuracy and reliability, flexible selection of the component base, magnets of various geometries and the flexible variation of their mutual placement in the sensor housing, and is also compatible with any best practices for adapting the device to the requirements of a particular measuring system, including post-assembly programming, redundant solutions, and conceptually sensor nodes.

Claims (10)

1. A non-contact true biaxial shaft angle sensor using a magnetic system based on a small dipole diametrically magnetized magnet that performs angular motion with two degrees of freedom in the working plane parallel to the front surface of the programmable two-axis Hall encoder with integrated magnetically concentrating (IMC) disks that perform physical conversion magnetic field in the working plane perpendicular to which the Hall sensor with IMC is truly sensitive, characterized in that other types of sensors are used, which are highly sensitive only to the components of the magnetic field in the working (XY) plane and are completely or relatively insensitive to the vertical component (Z) of the magnetic field, and the integral component of the true two-axis sensor can be mounted on either side of the board, also the central structural component or an element of the housing part — the insert — is rigidly connected to the housing and ensures accurate positioning of the dipole magnetic rotor relative to each other in the stator housing and an integral component of a biaxial magnetosensitive sensor with an optimal working distance between them, in addition, a dipole magnet magnetized in parallel with the plane in which the rotor makes a working angular movement with two degrees of freedom is used in the shaft angle sensor, there is also an integral true biaxial magnetosensitive sensor ( encoder) with sine-cosine primary output signals, included in the signal processing circuit, and a redundant integrated sensor, combining in one Ohm integrated case two magnetically sensitive elements. 2. The non-contact true two-axis shaft angle sensor according to claim 1, characterized in that such components are all magnetoresistive sensors based on the so-called XMR effects - AMR, GMR, TMP, CMR (colossal magnetoresistive), EMR (extraordinary magnetoresistive) and sensors Hall with vertical (non-planar) elements, sensitive only to the components of the magnetic field in the XY plane. 3. The non-contact true biaxial shaft angle sensor according to claim 1, characterized in that the other types of sensors are sensors that are sensitive specifically to the components of the magnetic field in the XY plane, AMR, GMR, TMP and other MR, and the sensors used in this device are sensitive to the direction, but not the magnitude of the magnetic field in the XY plane. 4. The non-contact true biaxial shaft angle sensor according to claim 1, characterized in that the two integral components of the true biaxial sensor can be mounted simultaneously on both sides of the board, providing a working distance between each microcircuit and the magnet in the magnetic system, which allows you to remove two sinus -cosine or angular signal at the same time or one of them in case of failure of one of the sensors (redundant system). 5. The non-contact true biaxial shaft rotation angle sensor according to claim 1, characterized in that the insert has a central circular hole that simultaneously limits unwanted rotor movements vertically and horizontally, as well as the optimal placement of a microcircuit or magnet in it. 6. The non-contact true biaxial shaft angle sensor according to claim 1, characterized in that the dipole magnet has any of the following forms: a solid cylinder, disk, cylinder or disk with a central through hole or through (groove) from the side adjacent to the magnetically sensitive sensor when installed in a magnet holder, an annular magnet (with a wide through hole), a magnet in the form of a rectangular parallelepiped or cube. 7. The non-contact true biaxial shaft angle sensor according to claim 1, characterized in that the signal processing circuitry which generates an output signal proportional to the rotation angle with a zero or reference value, with respect to which the rotation angle is calculated, also includes a reprogrammable EEPROM memory to perform such programming, in addition, and the signal processing circuit can be integrated into the integrated module of a true biaxial magnetosensitive sensor (encoder) or into an integrated true biaxial mag thread-sensitive sensor (encoder), which is an integrated sensor chip. 8. The non-contact true biaxial shaft angle sensor according to claim 1, characterized in that the redundant integrated sensor that combines two magnetically sensitive elements of one or different types in one integrated housing that produce two primary sine-cosine output signals each, for these primary signals, two external or integrated signal processing circuits form a double output signal proportional to the angle of rotation. 9. The non-contact true two-axis shaft angle sensor according to claim 1, characterized in that at the same time two integral sensors of one or different (including redundant) types in the stator housing of the device can be positioned on both sides of the printed circuit board and produce, at a minimum, two primary sine-cosine output signals each, for which two external or integrated signal processing circuits form at least a double output signal proportional to the angle of rotation. 10. The non-contact true two-axis shaft angle sensor according to claim 1, in which at least one integral truly two-axis magnetically sensitive sensor (encoder) with sine-cosine primary output signals is included in the signal processing circuit with a microcontroller that performs all signal processing functions and allowing the connection of other types of sensors, it is a non-contact, truly biaxial sensor unit for measuring the angle of rotation of the shaft.

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