RU2313763C2 - Contactless sensor of angular position with a linear angular diapason in the limits of 360 degrees - Google Patents

Abstract

FIELD: the invention refers to automobile electronic instrument making and may be used for definition of the angle of opening of the choker, the pressure degree of the accelerator's pedal, the position of the valve of recycling used gases.

SUBSTANCE: the arrangement has a rotor with diametrically magnetized magnet moving relatively to an immovable stator-programmed integral scheme of a double-axis angular encoder with an analog or pulse-width modulation output and an integrated cruciform massif of sensitive Hall's elements. The magnet is rigidly installed in a bushing with grooves for a screwdriver. The bushing is rigidly installed according to the results of leveling of the magnet in the adjusting bushing of the rotor with fulfilled in it an orienting flat or an orienting groove for installing on the shaft. The turning of the magnetic vector of the rotor is calculated according to the signals of the massif of planar Hall's elements sensitive to the perpendicular field of the integral scheme, on the basis of the algorithm CORDIC. The stator and the rotor are isolated from one another due to the inner lid-limiter rigidly fixed on the surface of the rotor.

EFFECT: makes it easier to define the angle of opening of the choker.

4 cl, 1 tbl, 23 dwg

Description

The invention relates to automotive electronic instrumentation and can be directly used in electronic vehicle control systems to determine the opening angle of the throttle, the degree of depressing the accelerator pedal, the position of the exhaust gas recirculation valve, in other automotive systems requiring an analog or PWM signal about the absolute angular position rotating object (shaft), as well as for non-contact detection of the absolute angular position of a large number of rotate REGARD objects in many other branches of light and heavy industry.

An analogue of the claimed sensor is an accelerator pedal position sensor (United States Patent 4915075 dated April 10, 1990).

The device describes a potentiometer and a board installed in the pedal with a circuit for generating a PWM signal, with an output duty cycle proportional to the position of the pedal.

The disadvantages of this device include the susceptibility to wear, characteristic of potentiometers, a short service life, low reliability, sensitivity to vibration and dust.

An analogue of the claimed device is an angular position sensor with a Hall device and a permanent magnet of a given shape (United States Patents 5159268 dated October 27, 1992).

The device describes two preferred options for the shape of the magnet - oblong and bell-shaped, allowing to achieve high linearity during its rotation.

The disadvantage of this device is the complexity of the magnetic system, the need to use magnets of a special shape and the application of calculated mathematical methods.

An analogue of the claimed device is a magnetic angle sensor with improved output linearity (United States Patents 5444369 dated August 22, 1995).

The device uses massive stationary axial magnetic circuits and a rotating magnetic circuit to which one or more magnets are attached.

The disadvantages of this device include bulkiness, structural complexity, the use of both calculation methods and device settings and adjustments, the lack of adaptation to the special requirements for the mechanics of automotive sensors operating in a limited range of rotation angles.

An analogue of the claimed device is a pedal position sensor with a magnet moving relative to a magnetic field sensor located in the stator channel (United States Patents 6577119 dated June 10, 2003).

The device describes a non-contact position sensor, in which the stator has a surface including two regions of magnetic material, the magnet is mechanically connected to the accelerator foot pedal, the relative movement of which along one or two Hall sensors in the stator channel causes the formation of an electrical signal proportional to the magnet’s movement, and is processed in integrated sensor circuits with one or two external ASICs (Application Specific Integrated Circuit) with programming capabilities, for example in EEPROM, linear output hara characteristics and temperature compensation, as well as the formation of a signal for transmission over a serial protocol, such as CAN bus.

The disadvantage of this device is the complexity of the described magnetic system, the need to use two Hall sensors to improve measurement accuracy, one or two external interface ASICs to implement the required interface.

The prototype of the proposed sensor is a measuring device for non-contact determination of the angle of rotation (United States Patent 6534971 dated March 18, 2003).

This device includes a rotor, on which is located a permanent magnet having a diametrical direction of magnetization, and a Hall element located asymmetrically and describing the elliptical rotational movement of the permanent magnet. However, no magnetic flux concentrators are used in this design. The indicated magnetic system makes it possible to obtain an output characteristic region with a steep lowering region and characteristic flat regions.

The disadvantage of this device is the narrowing of the range of the measured angle due to insufficient uniformity of the output characteristic (the description of the invention indicates the angular region of linearity to 80 °, while in many cases for the effective operation of the sensor it is necessary to measure angles of 100 ... 120 ° or more, up to 360 ° or, for some types of devices, even angles of several full revolutions), the presence of a flat portion of the curve, insufficient linearity of the characteristic in the full operating range.

The device lacks special circuitry and mechanical means of adaptation to the specific operating conditions of the sensor.

Conventional linear Hall sensors used in the design of the prototype have many disadvantages: low sensitivity, drift of sensitivity, displacement and significant non-linearity.

The objectives of the invention are improving the accuracy and repeatability of measurements, increasing sensitivity, expanding the functional range and linear portion of the measured angle to 360 °, improving the absolute and relative linearity of the signal of the absolute position (linearity of the analog signal or drift of the duty cycle of the PWM signal), improving reliability, developing adaptive signs to specific working conditions, including direct substitution of analog three-wire and two-wire (PWM) potentiometers, simplification of design devices and technologies for its assembly and installation.

The tasks are solved in that in a non-contact angle encoder including a rotor with a magnet moving relative to the stator with a magnetic field sensor, the stator is a programmable integrated circuit (IC) of a two-axis magnetic angular encoder with DSP based on the arctangent function (usually using CORDIC- algorithm), an analog or PWM interface, and an integrated cruciform array of Hall sensitive elements detecting the gradient of the working magnetic field perpendicular to the front face The surface of an IC sealed by surface mounting on a printed circuit board, the sensor rotor mechanically connected with the rotating shaft of the detected object, includes a diametrically magnetized cylindrical permanent magnet forming a working magnetic field, the light axis and the cylindrical base of which are parallel to the front surface of the IC, for alignment during assembly installed in a sleeve with grooves for a screwdriver, rigidly installed according to the results of alignment of the magnet in the mounting sleeve of the rotor with orienting flat or orienting groove for mounting on a shaft with a given initial orientation and having the ability to rotate in the housing at an angle limited at the extreme positions by stops in the base of the housing and the protrusions of the mounting sleeve of the rotor, for mechanical isolation of the stator from moving mechanical parts and limiting axial movements of the rotor , the sensor contains an inner cover - a limiter rigidly fixed in the housing on top of the rotor, the angular Hall encoder allows programming after assembly of the steam sensor meters of its analog or PWM output characteristic, zero position, detection of horizontal displacements of the magnet and its displacements in the vertical axis, the output connector of the sensor housing contains only the functional conclusions used in the process of operating the sensor after programming, and the technological conclusions and / or cable of the auxiliary technological connectors used only during a one-time programming process are removed from the sensor board before final installation of the top cover.

To ensure the main rotation of the rotor (clockwise), return movement (counterclockwise) within the measured angle and to increase reliability, a cylindrical or conical torsion return spring is introduced into the device, which counteracts the rotational movement of the control drive shaft.

The general circuit of the device, located on the sensor board, contains circuits for protection against reverse voltage, overvoltage, output short circuit, impulse noise along the power supply and output circuits.

A non-contact angle encoder with a linear angular range within 360 ° is shown in FIGS. 1-23.

Figure 1-4 shows the design of an analog non-contact throttle position sensor, figure 5-8 shows the design of an analog non-contact accelerator pedal position sensor. Figures 1 and 5 show projection views and a general axonometric view of the devices; Figures 2 and 6 show sectional views of sensors illustrating their principles of operation; Figures 3 and 7 show views of devices with an axial displacement limiter without a top cover; Figures 4 and 8 show views of devices with mechanically determined boundaries of the measured angle.

Figure 9 is a schematic electrical diagram of the inventive device with a 10-bit IC of a two-axis magnetic angular encoder AS5043 Austriamicrosystems, Figure 10 is a functional diagram of an AS5043 Austriamicrosystems IC, figure 11 is an illustration of the operating principle of a 10-bit two-axis magnetic angular encoder. On Fig shows the primary stage of generating signals of an array of Hall elements in the encoder IC, on Fig.13-16 shows the output interfaces supported by AS5043, serial SSI (Fig.13) and analog output modes (Fig.14). PWM interface AS5040 (Fig. 15), possible examples of analog output modes of the inventive device (Fig. 16). On Fig and 18 shows the programming of the sensor stage of recording data (Fig) and the mode of one-time programming (Fig). On Fig.19-22 shows the primary stage of the formation of the transfer characteristics (Fig.19) and typical programmable output characteristics of the classic Hall sensor (Fig.20-22). On Fig shows the analog output modes of the inventive sensor in comparison with the classic versions of the Hall sensors.

The table shows the technical characteristics of other known integrated components suitable for the sensor design described above as an alternative replacement, supporting an analog or PWM interface.

The designs of the angular position sensors shown in FIGS. 1-8 are very similar.

The throttle position sensor shown in figures 1-4, implements the operating mode with the rotation of the dipole magnet in a limited angular range of the mechanical angle φ = 120 ° and scans the two-dimensional distribution of the magnetic field with the formation of the output analog signal (for compatibility with most existing processing units) and a serial SSI data channel used when programming it once.

The throttle position sensor shown in Figs. 1-4 consists of a fixed stator housing 1, a rotor mounting sleeve 2, which also includes a diametrically magnetized cylindrical permanent magnet 3, pressed into a plastic adjustment sleeve - housing 4, cover 5 - axial beater limiter rotary a node mounted on screws 11, a printed circuit board 6, a biaxial angular encoder integrated circuit with an integrated cross-shaped array of Hall 7 sensing elements, connector pins 8, a sensor cover 9 and a torsion spring 10.

The accelerator pedal position sensor shown in FIGS. 5-8 consists of a fixed housing 1, a rotor mounting sleeve 2 of the rotor with a diametrically magnetized permanent magnet 3, pressed into a plastic sleeve 4, cover 5 - limiter axial beats of the rotor assembly, mounted on screws 11 , printed circuit board 6, IC of a two-axis angular encoder with an integrated cross-shaped array of Hall 7 sensing elements, contacts of connector 8 and cover 9.

The main elements of the sensor stator include the housing 1 and the integral sensor component - IS 7 (as well as all other elements not included in the rotor, belong to the stator), the rotor (the moving part of the sensor), based on parts rigidly interconnected, includes installation sleeve 2, a diametrically magnetized permanent magnet 3, pressed into the sleeve 4.

Most of the new accelerator pedal modules are equipped with a pair of external springs on the module pedal drive, for incorporation into which the sensor is designed. Since external torque limitation is assumed, the torsion spring, which is necessary in the throttle position sensor shown in Figs. 1-4 or other similar device without external torque limitation, is not involved in the design of the sensor shown in FIGS. 5-8.

In both designs, the throttle position sensor (Figs. 1–4) and the pedal position sensor (Figs. 5–8), the rotor mounting sleeve 2 is mechanically connected to the rotating shaft of the detected object (target) and can be rotated through a limited angle φ in the base of the housing 1. On the reverse side of the mounting sleeve 2 of the rotor there are flats or orienting grooves for mounting the device on a shaft with a given initial orientation. The housing 1 is rigidly fixed with two screws to the fixed part of the object.

The housing 1 is made in the assembly with the contacts of the connector 8 (according to the technology of pouring or pressing). Hall IC - a biaxial magnetic angle encoder 7 is mounted on the board 6 and sealed. Board 6 is installed in the housing 1 over the thrust pins of the bottom of the housing 1, the upper part of which is fused. The preferred mechanical orientation of the sensor 7 relative to the magnet 3 is ensured constructively. Contacts 8 are soldered on the board 6.

To mechanically limit the axial displacements of the rotor in the housing 1, a cover 5 is introduced — an axial beat limiter of the rotor fixed on the rotor in the housing 1 by screws 11. The angle φ is mechanically limited by the stops 12 at the base of the stator housing 1 and the protrusions 13 of the rotor.

The permanent magnet 3 is rigidly mounted (pressed and glued) in the sleeve 4. The sleeve 4 is provided with a groove for a screwdriver, which provides several useful design features:

1) the possibility of preliminary orientation of the zero plane of the magnet 3 symmetry in the groove for the screwdriver immediately before its rigid installation (according to the results of magnetic field measurements, for example, with a teslameter, a gaussmeter, a calibrated linear Hall IC, or using special hardware and software);

2) the ability to align the zero position of the magnet 3 during the assembly process;

3) increase the working area of alignment with a small magnet 3 (allows you to increase the groove for a screwdriver in the cover - stop 5);

4) it is allowed to use smaller working gaps between the magnet 3 and IS 7.

The initial placement of magnet 3 in the structures shown in Figs. 1-8 is not important: any mechanical position of the magnet, information about which is considered to be in the OTP register from the SSI channel, can be taken as zero (with a zero value of magnetic induction of zero) Fig. 13) data transmission ICs, for example, AS504x Austriamicrosystems family. For example, in the designs of Figs. 1-8, the bullet magnetic vector coincides with the zero reference vector of the effective electric angle (the principle of the sensor is shown in Figs. 11-12, the output interfaces are shown in Figs. 13-16), in contrast to the classical Hall sensors perpendicular fields, the working principle of the formation of the transfer characteristics of which is shown in Fig.19-22. The alignment of the magnet 3 relative to the IS 7 can be ensured during the assembly process, but the magnet 3 in the housing 4 is sealed with the alignment results in the rotor mounting sleeve 2.

3-pin output connector of the angle sensor with AS5043 - the principal circuit diagram of which is shown in Fig. 9, is intended to form the analog data channel shown in Figs. 14, 16. MagRngn conclusions. Mode, PROG and others, combined in connector X2, are technological and are used only in the process of programming the IC, the steps of which are shown in Figs. 17 and 18. After writing the data to the OTP register, immediately before installing the cover 9, the wire leads, technological jumpers and (or) connector X2 is removed from board 6.

The AS5043 10-bit programmable magnetic angle encoder is one of the most preferable options from the existing element base of two-axis angle encoders supporting an analog or PWM interface, the current state of which is shown in the table.

Functional diagram of AS5043 is shown in FIG. 10.

All stages of the signal processing in the AS5043 encoder IC are integrated, the IP magnetic angular Hall encoder with an integrated cross-shaped array of Hall elements with a special method of eliminating bias, known as the “spinning current”, produces an electrical image of the magnetic field perpendicular to the surface of the IC. Based on four primary analogue working signals proportional to the perpendicular components of the magnetic field, two sine-cosine signals are formed, which are functions of the angle of rotation of the vector of the parallel magnetic field. The Sigma-Delta ADC and DSP unit provide high-precision calculation of the angular position of the magnet relative to the IC (the angle of rotation of the magnetic vector parallel to the surface of the IC), using the arc tangent function and the CORDIC algorithm (Coordinate Rotation Digital Computer), as well as the values of the signals of the Hall elements. The CORDIC algorithm is used in the DSP of the encoder ICs to calculate the values of the signals of the Hall elements and the absolute value of the angle φ and is an iterative method for calculating the arctangent. Then the obtained digital value is converted into an analog or PWM signal.

AS5043 is characterized by the possibility of a single programming by the user of the parameters of the output characteristics of the sensor directly under operating conditions.

After switching on, programming of the AS5043 is allowed by the rising edge of the CSn pulse, with a high level at the Prog input. The 16-bit data configuration must be sequentially written to the OTP register via the Prog pin. The bit sequence includes: the first is the CCW rotation direction bit, 10 bits of information on the zero position of the magnet Z [9: 0] (the first is the most significant bit of the MSB) and analog mode settings: FB_ext EN - setting the operational amplifier (external or internal), RefExtEN - DAC reference voltage, ClampMd EN - mode (0 = 0-100%, 1 = 5-95% V _DD ), selection of the Output Range mode (OR0, OR1): [1: 0] 00 = 360 °, 01 = 180 °, 10 = 90 °, 11 = 45 ° (Fig. 17).

An important feature of the AS5043 is that the analog output can be configured differently: to work in the angle ranges of 360 ° / 180 ° / 90 ° or 45 ° (precise tuning of the angular range and adjustment of the slope of the curve can be performed by adjusting the output stage OPAMP), with an external or internal DAC voltage reference, output voltage ranges 0-100% V _DD or 5-95% V _DD , external or internal gain.

After writing the data to the OTP register, the data can be latched by the rising edge of the pulse at the output Prog of the programming voltage U _Prog 16 pulses CLK t _zapp must be transmitted for safety (Fig. 18). The programmed data takes effect the next time it is turned on.

To program the zero position, the magnet must be placed in the zero mechanical position of the system.

The angular position calculated by the cross-shaped array of IS Hall elements can be modeled as

,

,

where Y1 and Y2, X1 and X2 are the signals of the Hall elements. The zero angle φ will correspond to a zero magnetic vector with Y1 and Y2 equal to 0. The actual orientation of the zero plane of magnetic symmetry in the sensor case is not taken into account. The mechanical zero position is read through the SSI interface of the IC and assigned as a new zero position, which can be programmed into the OTP register. By changing the value of the zero position in the OTP register, it is possible to achieve coordination of the output with this mechanical position.

In normal operation, the AS5043 MagRngn output is an indicator of the magnetic field strength - the output with an open collector of low level indicates the output of the magnetic field from the recommended range of ± (45 ... 75 mT). The IC will still continue to work, but with poor performance: the data will be available through the SSI interface (Fig.13), but the low level status of MagRngn corresponds to the zero values of the analog outputs of AS5043.

Alignment mode AS5043 (or other AS504x family ICs: 10-bit AS5040. 12-bit AS5045) is designed to center the magnet relative to the ICs in order to achieve maximum accuracy. The alignment mode in the AS504x is enabled on the falling edge of the pulse output CSn in the high level state on the PROG pin. The SSI data bits are changed to the offset amplitude output value. The magnet is aligned when this value is less than 32 at all angles of rotation of the working angular range (up to 360 °). The larger the value obtained, the farther the magnet is from its preferred position at a particular angle of rotation.

In AS504x alignment mode, the MagINCn and MagDECn bits indicate a logical unit with an offset amplitude of less than 32.

The AS504x family of ICs returns to normal operation mode upon reinitialization.

Special attention is paid to the choice of magnets: magnets should be cylindrical in shape, diametrically magnetized. Austriamicrosystems recommends using a ⌀6 × 3 (preferably) magnet of any of the following types of magnet with AS504x: AlNiCo, SmCo5 or NdFeB. The magnetic field perpendicular to the surface of the sensor array, within a radius of 1.1 mm, should be ± 45 ... 75 mT, and its going beyond these limits is indicated by the MagINCn and MagDECn bits. With a ⌀6 × 3 magnet, the recommended working magnetic field is achieved at a distance of 0.5 ... 1.5 mm to the surface of the IC (plus 0.576 mm to the surface of the sensitive array). Austriamicrosystems also recommends the use of special ⌀6 × 2.5 BMN-35H Bomatec magnets made of NdFeB material with magnetization of the order of 1.2 mT for their AS5040 / 3/5 sensors.

Accessibility features of the AS5043 are provided by configuring the status of the MODE input pin. The absolute angular position is estimated at a speed of 10.4 kHz (0.1 ms) in fast mode (recommended for the full range of 360 °) or at a speed of 2.6 kHz (0.38 ms) in slow (high-precision and for angles ≤360 ° ) mode. Depending on the state of the mode input, the internal filter is activated or deactivated, which is used to reduce digital jitter and analog output noise.

An additional safety feature of AS5043 - the IC provides a warning in the event of a power failure.

An alternative IC element base for structures of this type is magnetic angle encoders with linear analog or PWM output, designed for programming only in the factory (AM512 RLS ICs) or using special output configuration (iC-MA iC-Haus).

For example, for factory-programmed AM512, the recommended magnet sizes are ⌀4 × 4 mm Sm2Co17, with a residual magnetization of the order of 1050 mT; the typical distance from the surface of the magnet to the surface of the sensor array localized on silicon in a radius of 2.4 mm for the AM512 is 2 mm. The amplitude value of the working magnetic field will be about 35 mT.

The same magnet sizes (⌀4 × 4 mm) with working magnetic induction values of about 20-100 mT are recommended for iC-MA iC-Haus, which supports 28 different operating modes, including analog ones: sine-cosine outputs, sawtooth resistor output for substitution of potentiometers and triangular output (with an amplitude value of 180 °).

In the design of the sensor can be used magnets of a different geometry, with greater or lesser distances to the IC. The basic conditions for the sensor’s operability are the recommended operating values of the magnetic induction given in the table. It should be noted that although magnets from any materials (Alnico, ferrites, SmCo or NdFeB) can be used in the inventive sensor, in automobile systems with an increased operating temperature, SmCo having the best temperature stability properties is the most preferred material.

In biaxial measurements, the axis of rotation of the cylindrical dipole magnet is centered with the array of measuring elements and is the reference point of the polar coordinate system to determine the angle φ of rotation of the easy axis (Fig. 11), which is associated with the configuration of an external sensor specially designed for mounting on the shaft end.

The use of a programmable IC of a biaxial angular encoder in combination with a rotating permanent magnet creating a working field allows one to obtain four primary analog working signals in the 360 ° range (Fig. 32), which is equivalent to the use of four classical Hall analog sensors in alternative designs and means simplifying the design assembly and installation technologies. Due to the build quality and uniformity of the magnetic surfaces, a further increase in the accuracy and repeatability of measurements, an increase in reliability is achieved.

The use of an array with four pairwise orthogonal Hall elements is associated with purely angular measurements, while the magnet alignment error is minimal. The use of Hall elements combined into an array additionally provides information on the direction (angle of rotation) of the magnetic field during its periodic change relative to the array of sensitive elements integrated into the Hall IC.

AS5043 type magnetic angle encoders are resistant to magnet displacements and external magnetic disturbances according to differential measurement techniques, air gap variations and temperature variations according to a sine-cosine signal estimate.

In addition, effective methods of eliminating the displacement of planar Hall elements, for example, the spinning current method, allow one to achieve bias values of the order of several μT. There are also effective ways to compensate for the amplification part, such as the auto-zeroing technique, consistent double sampling.

IC - magnetic angular encoders with an array of Hall sensitive elements provide the most compact solution for scanning the angular position of a permanent magnet located above or below the sensitive surface of the IC: the magnet used in this case, diametrically magnetized and cylindrical, can be significantly smaller in comparison with magnets for AMR sensors traditionally used in a similar configuration. The high sensitivity of integral sensors - magnetic angular Hall encoders allows the use of a working air gap in all configurations, sufficient to isolate the mechanical and electrical parts from each other.

The inventive sensor reflects, first of all, the introduction into the sensor of the angular position on the Hall effect, for example, the throttle or accelerator pedals described above, of a magnetic system based on a programmable IC of a two-axis angular encoder with a linear analog or PWM output in an angle range of 0 .. .360 °, and, secondly, the development of the adaptive features of the device to specific working conditions through the mechanics and circuitry (programming) of the sensor.

The development of adaptation features to specific working conditions is achieved through the use of a two-axis Hall encoder IC with an array of sensitive elements, an integrated signal processing circuit and a ready-made analog or PWM interface, as well as through the introduction of mechanical stops - stops of the measured angle and a rotor axial displacement limiter, rigidly fixed in the sensor housing, additionally due to the introduction of a return torsion spring, for example, in the throttle position sensor shown in Fig.1-4.

The introduction of an axial displacement limiter allows one to increase the magnetic sensitivity of the sensor (steepness of working magnetic signals), use smaller working gaps and weaker magnets, or adjust the gap, if necessary, while observing the state of the functional output of the magnet height. At small operating clearances, the limiter completely eliminates the risk of physical destruction of the microcircuit due to axial beats of the throttle actuator, pedals, etc., and mechanical vibration.

Compared to the magnetic system described above, but without an axial displacement limiter, introducing a limiter for using small working gaps means increasing the amplitude of the working magnetic signal, while maintaining the same uniformity and shape of the sinusoidal and cosine working signals and, as a consequence, their greater noise immunity, increased reliability, improved measurement accuracy, linearity index of the primary analog signals used in the encoder IC to calculate the angular position, repeatability and.

The design of the claimed device allows the use of any constant distance from the magnet for the location of the Hall IC, which is determined in this case from functional considerations (operability), which means simplifying the design of the device and the technology for its assembly and installation.

Programming in the IC the zero position of the magnet provides an arbitrary choice in the design of any position of the zero plane of the magnetic symmetry of the magnet relative to the sensor housing. Electric zero can be moved by software to anywhere in the mechanical range (for example, 30 ° or - 15 °). But in the case when the zero position of the magnetic plane of symmetry and the mechanical zero position of the rotor relative to the housing are as close as possible to each other, we can expect the fastest and most accurate (in serial production) coordination of the calculation of the arc tangent and the levels of primary magnetic sine-cosine signals at exactly zero the boundary of the mechanical angle - in connection with possible magnetic and mechanical tolerances.

Useful design features are provided by introducing orienting grooves (flats) in the sensor mounting sleeve and the magnet sleeve for quick mechanical adjustment of the position with a screwdriver, mechanical limiters of the axial displacement of the rotor with the magnet and the measured angle (stops in the sensor case), as well as the introduction of a return spring torsion to limit torque, if not performed externally. The flats in the sensor mounting sleeve and the groove in the magnet housing for the screwdriver provide identical technical characteristics for commercially available products.

The design of the inventive sensor is characterized by simplicity, manufacturability, reliability, a minimum set of mechanical and electrical components and a maximum set of adaptive features to specific operating conditions, including the most adapted interface.

Minimization of electronic components is achieved through the use of a Hall encoder IC with a high degree of integration (the minimum set of external interface components is used only in the absence of identical integrated tools), as well as by including only functional outputs in the sensor contact interface and reducing the number of auxiliary sensor outputs, not used in the future after its one-time programming, which means further simplification of the design of the device and the technology of its assembly and installation.

On Fig shows a comparison of the classical output characteristics of the Hall sensor and the three modes of the inventive device based on AS5043. 23 illustrates the expansion of the maximum mechanical, effective electrical and linear ranges of the measured angles of the inventive sensor, the boundaries of which can be specific, as in the example with AS5043, values in the range 0 ... 360 ° programmed during assembly, 360 ° / 180 ° / 90 ° / 45 °, and can be regulated more smoothly.

High linearity of the output signal and accuracy (≤ + 0.5 °) are ensured by integrated technologies: the differential principle of a quadratic array of elements, methods for eliminating bias, such as “spinning current”, which is implemented in all Austriamicrosystems ICs, computational and interface capabilities (theoretical principles) of encoders.

Thus, increasing the accuracy of measurements, repeatability, linearity (linearity of the analog signal or PWM signal duty cycle drift), expanding the functional range and the linear portion of the measured angle to 360 °, increasing sensitivity, developing adaptive features to specific working conditions, including direct replacing analog three-wire and two-wire (PWM) potentiometers, increasing reliability, further simplifying the design of the device and the technology for its assembly and installation are achieved through the use of optimized magnetic sensor system based on a cylindrical dipole magnet that produces rotation of the magnetic vector parallel to the surface of the Hall IC biaxial angular encoder with linear or PWM output.

Claims (4)

1. A non-contact angular position sensor with a linear angular range of 360 °, including a rotor with a magnet moving relative to a fixed stator with a magnetic field sensor, characterized in that the stator is a programmable integrated circuit (IC) of a two-axis magnetic angle encoder with digital signal processing (DSP) based on the arc tangent function, an analog or PWM interface and an integrated cross-shaped array of Hall sensitive elements detecting the working magnetic gradient I, perpendicular to the front surface of the IC, sealed by surface mounting on a printed circuit board, the sensor rotor, mechanically connected to the rotating shaft of the detected object, includes a diametrically magnetized cylindrical permanent magnet forming the working magnetic field, the light axis and the cylindrical base of which are parallel to the front surface of the IC, for alignment during assembly, rigidly installed in the sleeve with grooves for a screwdriver, rigidly installed according to the results of alignment of the magnet in the installation a rotor hub with an alignment flange or an alignment groove therein for mounting on a shaft with a given initial orientation and having the ability to rotate in the housing at an angle limited at the extreme positions by the stops at the base of the housing and the protrusions of the rotor mounting sleeve for mechanical isolation of the stator from moving mechanical parts and restrictions on the axial movements of the rotor, the sensor contains an internal limiter cover, which is rigidly fixed in the housing on top of the rotor; the angular Hall encoder allows programming after assembling the sensor, the parameters of its analog or PWM output characteristic, zero position, detection of horizontal displacements of the magnet and its movements in the vertical axis, the output connector of the sensor housing contains only the functional conclusions used during operation of the sensor after programming, and the technological conclusions and / or a wired loop of the auxiliary technological connector, used only in the process of a single programming, are removed from the sensor board before finally Attaching the top cover. 2. A non-contact angular position sensor with a linear angular range within 360 ° according to claim 1, characterized in that a cylindrical or conical torsion return spring is inserted into it. 3. A non-contact angular position sensor with a linear angular range within 360 ° according to claim 1, characterized in that the DSP IC is performed using the CORDIC algorithm. 4. A non-contact angular position sensor with a linear angular range within 360 ° according to claim 1, characterized in that the general circuit of the device, located on the sensor board, contains circuits for protection against reverse voltage, overvoltage, output short circuit, and pulse interference on the power supply circuit and exit.

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