EP4189331A2

EP4189331A2 - Detection device for a position sensor and detection system comprising such a detection device

Info

Publication number: EP4189331A2
Application number: EP21754780.1A
Authority: EP
Inventors: Franz Straubinger; Markus Simon
Original assignee: Sumida Components and Modules GmbH
Current assignee: Sumida Components and Modules GmbH
Priority date: 2020-07-30
Filing date: 2021-07-30
Publication date: 2023-06-07
Also published as: WO2022023550A2; WO2022023550A3; KR20230042375A; US20230304831A1; CN116507884A; DE102020209601A1; JP2023536824A

Abstract

The invention relates, in several clear embodiments, to a detection device for a position sensor and to a detection system comprising such a detection device. The detection device comprises, in some embodiments, at least one primary winding and a secondary winding circuit. The secondary winding circuit has a plurality of secondary windings which are inductively coupled to the at least one primary winding, and the plurality of secondary windings is designed as two sinusoidal coils, each having a center tap.

Description

Detection device for a position sensor and detection system with such

detection device

The present invention relates to a detection device for a position sensor and a detection system with such a detection device. In particular, the present invention relates to a detection device that is used in a position sensor in order to detect an angular position of the sensor element relative to the detection device together with a sensor element that is arranged rotatably relative to the detection device.

In many technical areas it is necessary to determine the position of a moving object with an accuracy that is specified by the respective application. Numerous sensor systems have been developed for this purpose, in which at least the relative position between two elements can be measured with sufficiently high precision, for example by optical, electrical, magnetic and other interactions. Especially in technical areas where very demanding environmental conditions prevail, such as high operating temperatures in connection with high magnetic fields, e.g. B. can be caused by high operating currents, Sensoranordnun gene are often used in which the position-dependent generation of eddy currents is used to determine the position of a component. For this purpose, in some examples, such an eddy current sensor arrangement is provided, which detects damping of one or more coils caused by eddy currents, the one or more coils being provided as stationary components and a moving component having a track made of a suitable material, which a position-dependent generation of eddy currents and thus damping. On the basis of this position-dependent eddy current generation, the position of the moving track with respect to the one or more stationary coils can thus be determined by a correlation of the damping caused and the special shape of the track.

An exemplary application in this regard is determining the position of a rotor of an electrical machine in order to use it to determine suitable control signals for supplying suitable current and voltage values. For example, in many cases where very variable rotational speeds and a moderately large control bandwidth are required for the electrical machine, it is important to acquire output voltage signals from sensor systems with a high temporal resolution in order to be able to determine the position of the rotor relatively precisely. With regard to efficient operation of permanent magnet synchronous machines, for example, it is necessary to position the rotor according to the number of poles to know within an angular section with good accuracy in order to energize stator windings appro net so that a desired mode of operation is established. Contactless sensor arrangements based on coils are often used for this purpose, but they require a relatively large amount of space for the coils and the associated evaluation electronics. A spatially very close coupling between the encoder element and rotor in the electrical machine's is often required, with high currents with correspondingly high magnetic fields and relatively high temperatures occurring in the vicinity of the encoder element, which lead to disturbances in the output signals of the coils. This susceptibility to interference ultimately also results in poorer spatial resolution of the position of a rotor. In addition to a desired interference immunity with regard to high magnetic fields, an adaptation of the sensor arrays to the operating conditions of the electrical machine is also desirable with regard to sensor arrays for electrical machines, for example with regard to the prevailing temperatures, the required speed range, and the like.

In addition to the above aspects, there are independent of a specific application with regard to the provision and integration of components of a sensor system, the requirements of a high level of constant precision in the manufacture of sensor arrangements, such as in mass production. This allows sensor configurations to function evenly without the need for time-consuming adjustment work during installation in the end application.

Document US 2017/0268907 A1 shows a position sensor with a rectangular primary coil surrounding two sinusoidal secondary coils. These coils are formed in a printed circuit board. A position transmitter is also provided here for position determination, as a result of which a position along a linear movement is determined.

The publication WO 2006/074560 A2 shows an eddy current sensor which is provided on a magnetic bearing device in order to carry out a distance measurement on the bearing.

A position sensor is known from document US 2015/0362340 A1, which has a primary coil, a plurality of secondary coils and a transmitter element. The coils are integrated into a printed circuit board.

In known rotor position sensors, there is the problem that secondary windings that are not arranged uniformly over a full circle around an axis cause an offset in signals that are output by the secondary windings due to the inevitably asymmetrical arrangement of the secondary windings around the axis. Furthermore, there is an offset in Phase signal from rotor position sensors, which occurs when individual windings in rotor position sensors experience couplings of different strengths through neighboring windings, in particular when windings are only arranged over a section of a full circle, since outer windings, in contrast to inner windings, have only one neighboring winding. These offsets in signals, which are caused purely by the arrangement of windings in rotor position sensors, therefore represent sources of errors that have a negative effect on the accuracy of rotor position sensors, unless compensation takes place.

In view of the prior art presented above, it is an object to provide a detection device and a detection system with such a detection device which, despite a compact design, has high precision and low susceptibility to faults.

The above object is achieved within the scope of independent claims 1 and 7 in that a phase shift is compensated for which is caused in the secondary winding circuits of detection devices for position sensors by the fact that not every secondary winding is coupled to adjacent secondary windings to the same extent. The starting point of the solution is the recognition that a phase shift arises from the outer secondary windings only "seeing" an adjacent secondary winding, while inner secondary windings "see" adjacent secondary windings on either side. This means that the secondary windings of a secondary winding circuit have different couplings to neighboring coils, since the secondary windings are only arranged over a circle segment and not over a full circle, so that each secondary winding “sees” two neighboring windings. In view of an undesirable phase shift, a technical teaching is realized within the framework of the independent claims, which, from an economic point of view, uniformly compensates for the phase shift, since the phase shift is solved as an individual problem by the independent claims, which thus realize phase shift compensation.

In a first aspect, a detection device for a position sensor is provided, such as a rotor position sensor or a position sensor in general, which does not detect a position of a rotor of an electrical machine, but a position of any rotating part, such as a part that, for example, has a gear is flanged to a rotor of an electrical machine, or a rotating part which rotates only in a limited angular range or continuously. In the illustrative embodiments of the first aspect, the sensing device includes at least a primary winding and a secondary winding circuit. In this case, the secondary winding circuit has a plurality of secondary windings which are inductively coupled to the at least one primary winding. In this case, the plurality of secondary windings is designed as two sinusoidal coils, each with a center tap. Here “sinusoidal” also means “cosinusoidal” or a general shape resulting from a phase shift by any phase from a sinusoidal curve or a general shape resulting from a continuous deformation of a sinusoidal curve. Furthermore, “sinusoidal” can also apply to a curvilinear shape that merely corresponds to a section of a sine or cosine curve or a continuous deformation thereof.

The sinusoidal coils easily enable a sinusoidal measurement signal to be generated using a simple encoder structure in a detection system, for example with a strip-shaped encoder structure with a substantially constant width along the encoder structure over one revolution, but with the strip having interruptions, which ensure that a sinusoidal coil scanning the encoder structure has an overlap region (i.e. area of the coil projected onto the strip) between two interruptions, which results in a monotonically increasing or decreasing signal in the coil as the strip is scanned . The center tap of each sinusoidal coil enables tapping via a single secondary winding in each case in a simple manner.

For example, the center tap may be provided as a vertical contact in a printed circuit board if the secondary windings are configured as single or multi-layer sinusoidal planar coils. This means that sinusoidal windings are in the form of sinusoidal conductor tracks or a sinusoidal winding is formed or composed of one or more sinusoidal conductor track sections. In this case, a center tap is designed as a vertical contact in the printed circuit board, for example in the form of one or more vias, which divides a sinusoidal trace section in the middle into two subsections or two subsections that have a sinusoidal shape when viewed from above divided into two substantially equal track sections. In this context, “substantially” can mean a tolerance of at most 40% in a length of a track section, preferably at most 30% or at most 20% or at most 10%, more preferably at most 5%. Different layers can be connected to one another at the center tap of a multi-layer winding.

In a first embodiment of this aspect, the primary winding may be formed as a rectangular coil surrounding the plurality of secondary windings in plan view. This provides an advantageous coupling between the primary winding and the secondary windings.

In a second embodiment of this aspect, the plurality of secondary windings may comprise a first subset of at least two secondary windings arranged in series with one another and a second subset of at least two secondary windings arranged in series with one another. This allows differential switching of secondary windings in each subgroup. In this case, the detection device can also have a resistor or capacitor. For example, here the resistor or capacitor can be arranged between a secondary winding from the first subgroup and a secondary winding from the second subgroup and/or it can be arranged in parallel with a first secondary winding from the first subgroup, possibly with a second resistor or capacitor, which can be arranged in parallel with a first secondary winding from the second subgroup. On the one hand, the resistor or capacitor between a secondary winding from the first subgroup and a secondary winding from the second subgroup can be used to achieve phase alignment between the individual subgroups, and on the other hand, the resistor or capacitor can be arranged in parallel with the first secondary winding from the first subgroup possibly with the second resistor or capacitor in parallel arrangement to the first secondary winding from the second subgroup an offset adjustment can be achieved. This also allows a phase offset to be compensated for, which otherwise always occurs, since windings in an arrangement have couplings of different strengths to windings of adjacent coil pairs over only one circular segment, and/or an offset that occurs in an asymmetrical coil arrangement is compensated. In more advantageous configurations herein, improved temperature stability can also be achieved by a combination of a capacitor and a resistor.

In a third embodiment of this aspect, the at least one primary winding and the secondary winding circuit can be integrated together in a printed circuit board. This provides a very compact design for the detection device. In some specific illustrative embodiments herein, a number of primary windings and a number of secondary windings may be the same and one primary winding may be aligned with exactly one secondary winding (ie, a pair of coils is formed) in the circuit board. In this case, a 1:1 mapping between primary windings and secondary windings is provided, with a coupling between a primary winding and an associated secondary winding being improved. Furthermore, a sensitivity to electromagnetic Technical interference fields are reduced because the use of more than one primary winding in the primary winding circuit means that an area occupied by a primary winding in the circuit board is less than if only one primary winding is provided. Also, smaller sized primaries allow for space savings in the design of the primary winding circuitry since space is now available adjacent to and between individual primary windings. In addition to dispensing with a large-area primary winding, which offers a large capture area for interference fields, a size of a primary winding can be matched to a size of the associated secondary winding, which enables a coupling between primary windings and associated secondary windings to be improved and a secondary winding to be disturbed a primary winding associated with an adjacent secondary winding is reduced.

In an advantageous refinement of this embodiment, the secondary windings can be in the form of sinusoidal coils. Sinusoidal coils allow a sinusoidal measurement signal to be generated using a simple encoder structure in a detection system, for example a strip-shaped encoder structure with a substantially constant width along the encoder structure over one revolution, with the strip having interruptions that ensure that a sinusoidal coil scanning the transducer structure has an overlap region (ie area of the coil projected onto the strip) between two discontinuities which results in a monotonically increasing or decreasing signal in the coil as the strip is scanned. For example, the plurality of secondary windings can be designed as two sinusoidal coils, each with a center tap, whereby two secondary windings can be realized by means of a sinusoidal coil with a center tap.

In a fourth embodiment of this aspect, the secondary winding circuit may further comprise a first resistor arranged in parallel with a first secondary winding from the first subgroup and a second resistor arranged in parallel with a first secondary winding from the second subgroup. An offset adjustment can be achieved by the first resistor and the second resistor. In detection devices in which the secondary windings are not arranged uniformly over a full circle around an axis, an offset occurs in signals which are output by the secondary windings due to the inevitably asymmetrical arrangement of the secondary winding around the axis. Alternatively, a capacitor can be provided instead of the first resistor and/or a capacitor can be provided instead of the second resistor. Furthermore, only one of the first resistor and the second resistor can be provided, so that only in an offset adjustment is achieved in a subgroup, it being possible for a capacitor to be provided instead of this resistor, so that an offset adjustment is achieved by a capacitor only in a subgroup.

In an advantageous configuration of this embodiment, the secondary winding circuit can also comprise a first capacitor and a second capacitor, the first capacitor being arranged in parallel with a second secondary winding from the first subgroup and the second capacitor being arranged in parallel with a second secondary winding from the second subgroup is. This can increase temperature stability in each subgroup in the case of a combination of the first resistor and the first capacitor in the first subgroup and a combination of the second resistor and the second capacitor in the second subgroup. Alternatively, only one of the first and second capacitors can be provided, so that improved temperature stability is only achieved in a subgroup.

In a second aspect, a detection device for a position sensor is provided, such as a rotor position sensor or, in general, a position sensor that does not detect a position of a rotor of an electrical machine, but a position of any rotating part, such as a part that, for example, has a gear machine is flanged to a rotor of an electrical machine, or a rotating part which rotates richly or continuously only in a limited Winkelbe. In the illustrative embodiments of the first aspect, the detection device for a position sensor comprises at least one primary winding and a secondary winding circuit with a plurality of secondary windings which are inductively coupled to the at least one primary winding, the plurality of secondary windings being a first subgroup of at least two mutually in secondary windings arranged in a series and a second subgroup of at least two secondary windings arranged in a series with one another, and wherein the secondary winding circuit further comprises a first resistor or capacitor which is arranged between a secondary winding from the first subgroup and a secondary winding from the second subgroup or which is arranged in parallel with a first secondary winding from the first subgroup or the second subgroup.

In some embodiments of this aspect, the at least one primary winding and the secondary winding circuit may be integrated together into a printed circuit board. In some embodiments of this aspect, a number of primary windings and a number of secondary windings can be the same and one primary winding can be aligned with exactly one secondary winding in the printed circuit board.

In some embodiments of this aspect, the secondary winding circuit may further include an additional resistor or capacitor disposed between two other secondary windings each of which is one of the first subset and one of the second subset.

In some embodiments of this aspect, the plurality of secondary windings may be formed as two sinusoidal coils, each center-tapped, and only one primary winding formed as a rectangular coil surrounding the secondary windings in plan view may be provided.

In some embodiments of this aspect, the secondary windings in each subset may be arranged in the secondary winding circuit connected relative to the or at least one primary winding such that a differential signal is provided by each subset during operation of the sensing device.

In some embodiments of this aspect, the secondary winding circuit may further comprise a first capacitor and a second capacitor, wherein the first capacitor is arranged in parallel with a second secondary winding from the first subgroup and the second capacitor is arranged in parallel with a second secondary winding from the second subgroup .

In a third aspect, a detection system is provided. In illustrative embodiments, the detection system comprises a detection device according to the first or second aspect and a transmitter element that is arranged rotatably relative to the detection device, wherein the transmitter element has a transmitter structure that is formed from an electrically conductive material.

In the detection system of the third aspect, an angular position between the detection device and the encoder element is advantageously detected when the encoder element is moved relative to the detection device. For example, a relative rotary motion between the encoder element and the detection device can be caused by a rotary motion of a rotor, in special applications this can be a rotor of an electrical machine, a rotor in the secondary winding Generate lungs induced voltage depending on a current position of the donor element to the detection device. In other words, a magnetic field generated by the primary winding circuit is modulated by the pickup element and the modulated magnetic field induces in the secondary windings of the sensing device a voltage signal that is a signal modulated by a pickup structure of the pickup element of the electrical signal applied to the primary winding circuit is, wherein the transmitter structure has a form or shape of the transmitter structure that varies as a function of the angle along a rotation of the transmitter element with respect to the detection device.

In the detection device according to the first and/or second aspect, the primary and secondary windings may be provided as air coils, which means that the primary and secondary windings are provided without a magnetizable core. In this case, due to the lack of a magnetic core material in the coil, external magnetic fields do not contribute, or only to a tolerable extent, to magnetization or saturation, so that the output signal obtained is relatively immune to interference, for example compared to the large magnetic fields used in electrical machines appear. Thus, eddy current losses of the encoder structure can be used to influence the output signals of the detection device, if this is at least partially made of an electrically/magnetically conductive material, so that the detection device according to the first and second aspect is immune to interference with regard to electromagnetic influences. For example, air coils are wound and mounted on a carrier such as a suitable substrate or printed circuit board or flexible circuit board.

Further advantages and illustrative embodiments of the aspects of the invention presented above are described below with reference to the accompanying figures, in which:

1a-1b schematically show a rotor position sensor according to some illustrative embodiments in plan views, the view in Fig. 1b being a sectional view taken along line 1b-1b in Fig. 1a;

FIG. 2 schematically shows, in a cut-away perspective view, a rotor position sensor in accordance with other illustrative embodiments; FIG.

3 schematically shows in a plan view a sensing device according to some illustrative embodiments; 4 schematically shows an arrangement of secondary windings with respect to a sensor structure and the resulting output signals of the detection device according to some illustrative embodiments;

5 schematically shows arrangements of individual secondary windings with respect to a transmitter structure according to some illustrative embodiments;

6 schematically shows in top view a primary winding and a plurality of secondary windings according to some illustrative embodiments;

7 schematically illustrates, in top view, center-tapped secondary windings, in accordance with some illustrative embodiments;

Fig. 8 schematically in a top view secondary windings with several turns and

12 shows a center tap in accordance with some illustrative embodiments

9 schematically shows a circuit view of a detection system according to some illustrative embodiments;

10 schematically shows a sectional view of a sensing system with a pair of coils disposed in a printed circuit board, according to some illustrative embodiments;

11 schematically shows a circuit view of a detection system according to some other illustrative embodiments;

12 schematically shows a circuit view of a detection system according to still some other illustrative embodiments; and

13 schematically shows a circuit diagram of a plurality of primary windings according to some illustrative embodiments.

Various illustrative embodiments described below may relate to an application of detection devices in rotor position sensors. According to illustrative embodiments, a rotor position sensor generally comprises a detection system for detecting an angular position between a detection device of the detection system and a sensor element of the detection system. The encoder element has an encoder structure which is formed from an electrically/magnetically conductive material and, in the case of a complete rotation (ie a rotation of 360° about an axis of rotation of the encoder element, relative to the detection device) changes as a function of the angle, as a result of which an angular position between the detection device and the encoder element is detected.

A primary winding circuit in the detection device generates a magnetic field that is modulated by the transmitter structure of the transmitter element. A correspondingly modulated magnetic field in turn induces correspondingly modulated electrical signals in a plurality of secondary windings of the sensing device. From a comparison between an electrical signal that is applied to the primary winding circuit for generating the magnetic field and the electrical signal that is output by the secondary windings in response to this, an angular position between the transmitter element and the detection device can be inferred.

With reference to FIGS. 1a, 1b and 2, two alternative configurations for a rotor position sensor with a detection system for detecting an angular position between a detection device and a sensor element of the detection system are now described.

Fig. 1a shows a schematic side view of a rotor position sensor 1 of an electrical machine. In this case, a transmitter structure 3 is attached to an axial surface of a rotor, for example a rotor 2 of an electrical machine, and can be moved with it. In illustrative examples, the electrical machine can be a permanent magnet excited machine in which an angle signal is used for electrical commutation. Furthermore, a detection device 4 is provided, which is arranged axially opposite the encoder structure 3 . The sensor structure 3 and the detection device 4 form a detection system for the rotor position sensor 1, with the sensor structure 3 being arranged so as to be rotatable relative to the detection device 4.

According to illustrative embodiments, the encoder structure 3 is applied to a suitable carrier material 7a or attached directly to a base material of the rotor 2, which is seated on a shaft 2a. A base material of the rotor 2 is understood to mean a material that is intended for the function of the rotor 2, such as a material for holding components of the electrical machine, such as magnets and the like.

1b shows a section along the line 1b-1b in FIG 2 around the shaft 2a by 360°). However, this does not constitute a limitation of the present invention and track 3a can instead be configured as a strip of substantially constant width (without the in Fig. 1b shown periodically varying width, with periodic interruptions in Strei fen are provided) or be designed as a strip with monotonically over a complete mechanical revolution of the rotor's 2 changing width. According to some exemplary configurations, the encoder structure 3 can have repeating triangular structures instead of the track 3a illustrated in FIG. 1b. However, other shapes that result in a position-dependent change in inductance, such as rectangular structures, etc., can also be used. In some illustrative examples, the donor structure 3 may comprise aluminum, steel, copper, a printed circuit board, one or more conductive foils, or a metalized plastic, for example. In general, the transmitter structure 3 can only be electrically conductive, in particular the transmitter structure is not magnetic or magnetisable, and can therefore comprise an electrically conductive component embedded in or attached to a carrier material of the rotor 2 that is not electrically conductive. However, this does not restrict the invention and the sensor structure can be formed by a magnetic or magnetizable material that is embedded in a carrier material of the rotor 2 or placed on it.

Referring to FIG. 2, a cut-away perspective view schematically shows a rotor position sensor 10 according to illustrative embodiments in which the rotor position sensor 10 is mounted on a motor and is configured as an alternative configuration to the rotor position sensor 1 of FIGS. 1a and 1b. The rotor position sensor 10 has a detection system that is formed from a detection device 12 and a sensor structure 14 , the sensor structure 14 being arranged to be rotatable about a rotor axis R with respect to the detection device 12 . The transmitter structure 14 is in this case attached to a radial surface of a rotor, for example a rotor 18 of an electrical machine, and can be moved with it. As shown in FIG. 2, the motor has a stator coil 19 wound on a stator of the motor. The transmitter structure 14 may be formed in accordance with the transmitter structure 3, reference being made to the above description in this regard.

According to the representation in FIG. 2 , the detection device is arranged radially opposite to the encoder structure 14 on the outside on a motor housing 16 of the motor, the stator coil 19 being at rest relative to the rotor 18 . In the illustration of FIG. 2, the motor housing 16 is partially cut away for reasons of illustration in order to show the transmitter structure 14 arranged under the detection device 12, which would otherwise be covered by the motor housing 16 in the perspective view of FIG.

According to some illustrative embodiments, sensing device 12 may include a plurality of windings (not shown) and electronic circuitry (not shown). which processes the signal output by the windings and outputs them as position signals, such as electrical signals such as voltage amplitudes, differential voltages, current amplitudes, differential currents, frequencies, phase angles, etc., a rotational angle position of the rotor 18 relative to the detection device 12 being derivable from these electrical signals .

With reference to FIG. 3, some illustrative embodiments of a detection device 20 are explained in more detail below. The sensing device 20 includes a printed circuit board 22 having a plurality of coils, such as a plurality of secondary windings 24a, 24b, 24c and 24d, disposed in the printed circuit board 22 side-by-side. Furthermore, at least one primary winding (not shown) can be formed in the printed circuit board 22 . For example, a single primary winding (not shown) may be provided, which primary winding (not shown) may surround the secondary windings 24a through 24d in the plan view shown in FIG. Alternatively, two primary windings (not shown) can be provided, with one of the primary windings (not shown) surrounding the two adjacent secondary windings 24a and 24b in the plan view shown, while the other primary winding (not shown) surrounding the two adjacent secondary windings lungs 24c and 24d may surround in the top view shown. In a further alternative, four primary windings (not shown) can be provided, with each of these primary windings (not shown) being able to overlay one of the secondary windings 24a to 24d essentially congruently.

The secondary windings 24a to 24d may be in the form of rectangular coils (as shown in phantom in FIG. 3). By the term rectangular is meant a shape that results from a rectangle by deforming (stretching or compressing at least one side of the rectangle) the rectangle (such as a trapezoid) or is a rectangle. Compression of a line to a point should also be understood as falling under the term “deforming”, so that a rectangle can also be deformed into a triangle.

According to some illustrative embodiments, the printed circuit board 22 can be used in the rotor position encoder of FIGS. 1a and 1b in such a way that the printed circuit board 22 would be identified with the reference number 4 in connection with FIG. 1b. In this case, the term rectangular would also mean a shape that can result from a rectangle by deforming (as described above), it also being possible for at least one radial side of a deformed rectangle to have a curvature in an axial arrangement according to FIG. 1b , which essentially curves on a radial line around the shaft 2a in Fig. 1b in circuit board 22 (see reference numeral 4 in Figure 1b in this regard). In other words, a correspondingly curved radial side can correspond to a circular arc section around the shaft 2a in Fig. 1b at the location of the radial side with respect to the shaft 2a.

According to other illustrative embodiments, the printed circuit board 22 can be used in the rotor position encoder of FIG. 2 in such a way that the printed circuit board 22 in connection with FIG. 2 faces the detection device 12 in FIG would identify. This lower surface of the sensing device 12 in FIG. 2 may be planar or formed according to a circular arc section about the rotor axis R in FIG. 2 at the location of the lower surface of the sensing device 12 in FIG. In this case, the term rectangular would also mean a shape that can result from a rectangle by deforming (as described above), it also being possible for at least one radial side of a deformed rectangle to have a curvature in a radial arrangement according to FIG. which substantially corresponds to a curvature on a radial line about rotor axis R in FIG. 2 in circuit board 22 (cf. lower surface of sensing device 12 in FIG. 2 in this regard). Furthermore, the printed circuit board 22 can be oriented in an application as an element of the detection device 12 in FIG. 2 in connection with FIG. 2 in the detection device 12 of FIG R in Fig. 2 would be oriented.

Referring to FIG. 3, an embodiment is shown in which the secondary windings 24a-24d are integrated into a material of the circuit board 22, illustrated by the dashed representation of the secondary windings 24a-24d. This provides improved integrity of the secondary windings 24a-24d even under severe environmental conditions. For this purpose, the secondary windings 24a to 24d can be encapsulated or cast with a suitable material, with or without a carrier material, or can be installed in a housing or only provided with a printed circuit board. When the secondary windings are overmolded or encapsulated, each of the secondary windings 24a to 24d does not necessarily have to be completely embedded in the material of the printed circuit board 22, but an uppermost conductor surface of each of the secondary windings 24a to 24d can remain free or the covering of the secondary windings 24a to 24d can be small, so that together with a thickness of the material of the printed circuit board 22, a desired gap to a transmitter structure (not shown) results. Alternatively, the secondary windings may be mounted on the printed circuit board 22 and connected to electrical leads (not shown) in the printed circuit board 22 via external terminals (not shown) of the printed circuit board 22 . With regard to FIGS. 1 to 3, it is noted that due to the smaller dimensions of the detection devices shown compared to a circumferential length of the encoder structures shown, the secondary windings and correspondingly also the primary winding(s) (not shown) are arranged only over a circular arc section of the stator .

Referring to FIG. 4 , a relationship between transmitter structure and secondary windings is described, according to some illustrative embodiments, and the electrical signals output from the secondary windings.

Fig. 4 shows schematically the arrangement of a transmitter structure 36 of a transmitter element 37 in relation to a plurality of secondary windings 50. The plurality of secondary windings 50 is formed by four secondary windings 34a, 34b, 34c and 34d, which are shown as rectangular windings and with reference are arranged on the transmitter structure 36 side by side. In this case, the transmitter structure 36 represents a structure as described above with reference to the preceding figures, so that the above description is not repeated here. In particular, the encoder structure 36 is a structure formed from an electrically conductive material, which is formed periodically along one or more revolutions of a rotor (not shown), for example at least one period of the encoder structure 36 means a full revolution of the rotor (not shown).

With reference to FIG. 4 , the secondary windings 34a to 34d are arranged side by side with respect to the transmitter structure 36 such that the secondary windings 34a to 34d are arranged substantially equidistant from one another along a period of the transmitter structure 36 . A section of the transmitter structure 36 can thus be assigned to each of the secondary windings 34a to 34d, so that the transmitter structure 36 is divided into four sections which are essentially of equal size along the period of the transmitter structure 36 . In other words, the secondary windings are offset from each other by a quarter of the period of the transmitter structure 36 with respect to the period of the transmitter structure. Thus, the secondary winding 34a has a relation of a quarter of the period of the sensor structure 36 to the secondary winding 34b, the secondary winding 34a has a relation of half a period of the sensor structure 36 to the secondary winding 34c and the secondary winding 34a has a relation to the secondary winding 34d a relation of three quarters of the period of the encoder structure 36.

Also referring to the schematic representation of FIG. 4, there is shown a signal processing circuit 32 connected to the secondary windings 34a-34d that receives and processes electrical signals output by the secondary windings 34a-34d and outputs 30 as processed signals. In some illustrative examples, the signal processing circuitry may perform filtering and/or offset adjustment and/or phase adjustment, as discussed in more detail below. The secondary windings 34a and 34c are connected to one another in a subgroup 35a and output electrical signals to the signal-processing circuit 32. FIG. Furthermore, the secondary windings 34b and 34c are connected to each other in a subgroup 35b and output electrical signals to the signal-processing circuit 32. FIG.

The processed signals 30 shown in FIG. 4 are shown as an example over a time interval that corresponds exactly to one period of the transmitter structure 36 . In other words, the time interval illustrated represents an interval in which the plurality of secondary windings 50 sweeps or samples an entire period of the encoder structure 36 . With reference to the encoder structure 36, the signals output by the subgroup 35a are represented as “sine” in the processed signals 30, while the signals output by the subgroup 35b are represented as “cosine” in the processed signals 30. These sine and cosine signals allow an unambiguous identification of an angular position and direction of rotation of the secondary windings 34a to 34d with respect to the transmitter structure 36 and thus by a detection device comprising the secondary windings with respect to the transmitter structure 36.

Referring to FIG. 5, individual secondary windings 64a-64d are shown relative to different portions 63a-63d of a transmitter structure at the same time. It can be seen that between the sections 63a and 63b scanned by the secondary windings 64a and 64b there is an angular position of 180° relative to one period of the transmitter structure. Correspondingly, between the sections 63c and 63d scanned by the secondary windings 64c and 64d, there is an angular position of 180° relative to one period of the transmitter structure. On the other hand, between the sections 63a and 63c scanned by the secondary windings 64a and 64c there is an angular position of 90° in relation to one period of the encoder structure, while between the sections 63tec and 63d scanned by the secondary windings 64b and 64d there is an angular position of 90° in relation to one period of the donor structure.

Referring to FIG. 4, the secondary windings 64a-64d in FIG. 5 can be identified with the secondary windings 34a-34d, with portions 63a-63d then representing portions of the pickup structure 36 being sensed by the corresponding secondary windings 34a-34d at the same time .

In the embodiments described with reference to FIGS. 1 to 5, the transmitter structure can be sinusoidal on or on a transmitter element. The sinusoidal shape is advantageous liable, since this geometry enables the sensor structure to form a damping surface in the form of a sine track, which in turn can influence an electrical signal detected by a detection device in a sine-like manner and is therefore easy to evaluate. However, this does not represent a restriction and, in principle, other encoder structures can also be used, as has already been noted above. In general, encoder structures are not necessarily periodic several times during a full rotation, as long as an unambiguous assignment of electrical signals detected by a detection device scanning the encoder structure to a position or angular position of the detection device with respect to the encoder structure along a full rotation is possible.

In accordance with the above description of various embodiments, in a sensing system according to some illustrative embodiments, output signals modulated by a transducer element are provided from various subsets of secondary windings (see, for example, subsets 35a and 35b in FIG Frequency of an output signal corresponding to a transmitter structure of the transmitter element in the course of a rotational movement of the transmitter element relative to the detection device can be changed. Subgroups of secondary windings can be defined with reference to the transmitter structure in that the electrical signals output by two subgroups have a phase offset of 90° with respect to one period of the transmitter structure. This allows the provision of output signals from the subgroups which are related to one another in a sine and cosine manner and can therefore be easily evaluated using known methods. Within a subgroup, the secondary windings can be arranged in relation to one another in such a way that they output electrical signals with respect to one another, which have either a phase offset of 180° in relation to a period of the encoder structure or a phase offset of 360° in relation to a period of the encoder structure . In the case of a phase shift of 180°, the signals output by the secondary windings in a sub-array can be provided as differential output signals of the sub-array, so that identical spurious signals generated by each secondary winding in a sub-array are compensated for.

Illustrative embodiments are described with reference to FIGS. 6 to 8, in which the secondary windings are formed as sinusoidal coils. In the case of sinusoidal secondary windings, it is not necessary for a transducer structure of a transducer element to have a varying structure along a complete rotation. If a periodically changing transmitter structure is sampled by a sinusoidal secondary winding, an electrical output signal is produced which represents a sine signal modified in accordance with the periodically changing transmitter structure. For example, a sinusoidal Sensor structure sampled by a sinusoidal secondary winding to an electrical signal proportional to sin ² .

Referring to Figure 6, a sensing device 100 is shown schematically. The sensing device 100 includes a primary winding 110 and a plurality of secondary windings provided by the sinusoidal coil 120a and by the sinusoidal coil 120b. The primary winding is a rectangular coil surrounding the plurality of secondary windings in the plan view shown. A circuit board of the registering device 100 is not shown.

Each of the sinusoidal coils 120a and 120b is formed from two sinusoidal coil sections which have a phase offset of 180° with respect to their sinusoidal shape. Thus, each of the sinusoidal coils 120a and 120b is represented in its shape similar to "°°". however, are offset by 90° relative to their sinusoidal shape. This represents an advantageous but non-limiting example in which corresponding coils can be easily mass-produced and an output of sinusoidal signals is guaranteed.

Because each of the sinusoidal coils 120a and 120b overlaps and overlaps one another multiple times, the sinusoidal coils 120a and 120b are preferably formed as multi-layer coils in which vertical contacts V between the individual layers establish an electrical connection. With respect to the secondary windings and the primary winding 110, the vertical contacts also serve as outer contacts. However, this does not constitute a restriction and an overpass and/or underpass such as a bridge contact can only be provided at a point where crossover would occur, with the secondary windings, with the exception of the bridge contacts, being in the same plane of a printed circuit board would walk.

Referring to FIG. 7, an alternative embodiment to FIG. 6 is shown. More specifically, a sinusoidal coil 220 is shown having two secondary windings 222a and 222b, each one turn, with the secondary windings 222a and 222b being arranged in series and having opposite winding senses to one another. Vertical contacts V1 and V7 represent external contacts to sinusoidal coil 220, such that vertical contact V1 represents external contact of secondary winding 222a, while vertical contact V7 represents external contact of secondary winding 222b. More vertical contacts V2, V3, V4, V5 and V6 are used for vertical connection between different horizontal planes (not shown) of a printed circuit board (not shown) in which individual winding sections of the sinusoidal coil 220 run. For example, sections that extend between vertical contacts V1 and V2, V3 and V1, and V5 and V6 lie in a first plane, while sections that extend between vertical contacts V2 and V3, V4 and V5, and V6 and V7 lie in a second level different from the first level. A center tap M1 is realized by the vertical contacts V4, so that a voltage signal can be tapped across the secondary winding 222a between V1 and M1 and a voltage signal across the secondary winding 222b between M1 and V7.

The center tap M1 allows each of the secondary windings 222a and 222b to be connected to an electrical component to allow for a correction in the signal output by the sinusoidal coil 220.

Referring to FIG. 8, an alternative embodiment to FIG. 7 is shown. More specifically, a sinusoidal coil 320 is shown having two secondary windings 322a and 322b each with multiple turns, the secondary windings 322a and 322b being arranged in series and having opposite winding senses to one another. Vertical contacts represent external contacts to the sinusoidal coil 320 and internal connections between different planes in which individual winding sections of the sinusoidal coil 320 run, in analogy to the above description of Fig. 7. Furthermore, a center tap M2 is implemented so that a voltage signal across secondary winding 322a and a voltage signal across secondary winding 322b can be tapped through M2.

Referring to FIG. 9 , a detection system 400 with a detection device 410 and a transmitter element is shown, which is illustrated using a transmitter structure 420 of the transmitter element in FIG. 9 . While the encoder structure 420 is shown as a sinusoidally varying structure, this is not a limitation and alternative encoder structures may be employed, as variously noted above. A direction of rotation, in which the transmitter element moves relative to the detection device 410, is shown in FIG. 9 by means of an arrow DR for illustration.

As shown in FIG. 9, the sensing device 410 includes a plurality of primary windings 402 and a plurality of secondary windings 404 . These windings can be integrated into a printed circuit board (not shown), as described above with reference to various illustrative embodiments. The plurality of primary windings 402 includes four primary windings 402a through 402b and the plurality of secondary windings 404 has four secondary windings 404a to 404b. The number of secondary windings is not limited to four, and a multiple of four secondary windings can be provided. With regard to the number of primary windings, instead of four primary windings, a number of primary windings can be provided which corresponds 1:1 to the number of secondary windings. Alternatively, a subgroup of secondary windings from the plurality of secondary windings can be assigned to exactly one primary winding. For example, one primary winding from a plurality of primary windings can be assigned to two or more secondary windings, so that each primary winding is assigned to a subgroup of secondary windings, with each subgroup having the same number of secondary windings.

With reference to FIG. 9, an electronic circuit 430 is provided which, on the one hand, applies an electrical signal to the plurality of primary windings 402 and, on the other hand, receives electrical signals output by the plurality of secondary windings 404 . For example, the electronic circuit can have an oscillator circuit (only oscillator connections Osz1 and Osz2 are shown in FIG. 9) by which a periodic electrical signal is applied to the plurality of primary windings 402.

The plurality of primary windings 402 can be connected in a resonator circuit 403 which is fed by the oscillator circuit of the electronic circuit 430 . For example, the plurality of primary windings 402 may be formed by connecting the primary windings 402a through 402d in series. However, this is not a limitation and a suitable parallel connection of at least some of the primary windings 402a to 402d can be provided.

The secondary windings 404 a to 404 d of the plurality of secondary windings 404 may be divided into subgroups of two secondary windings arranged in series, which are separately connected to the electronic circuit 430 . For example, secondary windings 404a and 404c may be in series with one another and form one subset of secondary windings, while secondary windings 404b and 404d may be in series with one another and form another subset of secondary windings. Each of these subgroups provides electrical signals for the electronic circuit 430, on the basis of which an angular position can be determined in the detection system 400. The secondary windings in each subset are wound and connected relative to each other such that a voltage signal output from a subset is a differential signal. This means that a voltage signal output by a sub-array corresponds to a difference in voltages induced in the individual windings of the sub-array. Various embodiments in which each company group is arranged to output a differential signal are described in more detail below with reference to FIGS. 9, 11 and 12.

With regard to the embodiments described with reference to FIG. 9, this means that all primary windings 402a to 402d and all secondary windings 404a to 404d have the same winding direction relative to one another, but the secondary windings 404a and 404c are connected to one another in a subgroup in such a way that a Differential signal can be tapped. Likewise, the secondary windings 404b and 404d are connected to one another in another subgroup in such a way that a differential signal can be tapped off via this subgroup. Thus, a differential signal can be provided by the secondary windings 404a and 404c on the electronic circuit 430 through the "sin+" and "sin-" terminals, while a differential signal can be provided by the secondary windings 404b and 404d on the electronic circuit 430 through the "cos+" and "" terminals. cos-" a differential signal is also provided. With respect to one another, the electrical signals of the subset of secondary windings 404a and 404c, on the one hand, and the subset of secondary windings 404b and 404d, on the other hand, are periodic signals that are 90° out of phase with one another, as is apparent from the discussion of illustrative embodiments above.

With regard to other configurations of the transmitter structure 420 that are different from the illustrated transmitter structure 420 (as described above with regard to various configurations of transmitter structures), a suitable form for the secondary windings and primary windings can be selected, for example in the form of sinusoidal coils or rectangular coils.

In some illustrative embodiments, the plurality of primary windings 402 is arranged with respect to the plurality of secondary windings 404 such that one of the primary windings 402a to 402d and one of the secondary windings 404a to 404d are arranged in a pair of coils, so that these windings in the pair of coils have a have maximum inductive coupling compared to an inductive coupling between a winding from this pair of coils and a winding from another pair of coils. For example, this means in concrete terms that the primary winding 402a and the primary winding 404a form a pair of coils (402a, 404a), which is characterized in that an inductive coupling between the Pri mary winding 402a and the secondary winding 404a compared to an inductive coupling between the primary winding 402a and any one of the secondary windings 404b-404d and also to inductive coupling between the secondary winding 404a and any one of the primary windings 402b-402d. Correspondingly, the remaining windings 402b to 402d and 404b to 404d can also be arranged in pairs in coil pairs being. This can be implemented, according to a specific illustrative (but not limiting) example, in an arrangement of the windings in which a primary winding and a secondary winding are directly opposite or intertwined. This produces maximum signal strengths from each pair of coils, requiring little to no amplification of signals generated by pairs of coils. In other illustrative examples, the primary and secondary windings in a pair of coils may be congruent.

As shown in FIG. 9, the secondary windings 404a to 404d are connected in a secondary circuit, with every two secondary windings being connected to one another in a subgroup. Referring to FIG. 9 , secondary winding 404a and secondary winding 404c are coupled together in a subset of the plurality of secondary windings 404 and connected to electronic circuitry 430 . For example, the secondary windings 404a and 404c are arranged in series between a two-pole terminal sin+/sin- of the electronic circuit 430 . In this case, the secondary windings 404a and 404c can be arranged in series in such a way that the secondary windings 404a and 404c have opposite winding senses relative to one another in the series circuit. As a result, differential signals are output to the electronic circuit 430 from this subassembly. Furthermore, the secondary winding 404 b and the secondary winding 404 d form a subset of the plurality of secondary windings 404 and are connected to the electronic circuit 430 . For example, the secondary windings 404b and 404d are arranged in series between a two-pole connection cos+/cos− of the electronic circuit 430 . In this case, the secondary windings 404b and 404d can be arranged in series in such a way that the secondary windings 404b and 404d have opposite winding directions relative to one another in the series circuit. As a result, differential signals are output to the electronic circuit 430 from this subset. In this example, subgroups represent an interconnection of secondary windings which are directly connected without an element arranged in between.

According to the illustration in FIG. 9, at least one resistor and/or capacitor is also provided in the acquisition system 400 in order to achieve an adjustment of offsets and phases. As explained above, in rotor position sensors with detection devices in which the secondary windings are not arranged uniformly over a full circle around an axis, there is an offset in signals generated by the secondary windings due to the inevitably asymmetrical arrangement of the secondary windings around the axis be issued. In the present case, for the detection system 400, with an asymmetrical arrangement of the secondary windings 404a to 404d about an axis of rotation (not shown), to assume that an offset occurs in the signals. Furthermore, with an asymmetrical arrangement of the secondary windings 404a to 404d, phase deviations of 90° and 180° between the secondary windings and subgroups occur, since the secondary windings have couplings to adjacent windings of different strengths. For example, secondary windings 404a and 404d each have only one adjacent secondary winding, while each of secondary windings 404b and 404c has two adjacent secondary windings.

In illustrative embodiments, offset trimming in the secondary winding circuit may be accomplished by a resistor 406a-406d placed in parallel with a corresponding secondary winding. For example, only one resistor can be provided in each subgroup. It is also possible for only one resistor to be provided overall. Alternatively, more resistors may be provided, for example each of resistors 406a through 406d may be provided.

In illustrative embodiments, phasing in the secondary winding circuitry may be accomplished by a resistor 408a-408d, each electrically connecting an input/output of one subset and an input/output of the other subset. One of the resistors 408a to 408d can be sufficient for this. If necessary, one of the resistors 408a to 408d can be combined with another resistor thereof.

A capacitor can be provided instead of at least one of the resistors 406a to 406d and/or at least one of the resistors 408a to 408d. A combination of a resistor and a capacitor can contribute to improved temperature stability. For example, one of the resistors 406a and 406c in the subset of the secondary windings 404a and 404c may be replaced with a capacitor placed in parallel with the corresponding secondary winding in that subset. Additionally or alternatively, one of the resistors 406b and 406d in the subset of the secondary windings 404b and 404d may be replaced with a capacitor placed in parallel with the corresponding secondary winding in that subset. Additionally or alternatively, one resistor may be provided from resistors 408a-408d and a capacitor may be provided in place of any of the remaining resistors from 408a-408d.

Concrete values for resistors and capacitors in the secondary winding circuit depend primarily on the layout of the detection device 410 and the detection system 400, respectively. At the beginning of a development, various measurements and/or simulations can be carried out be performed to determine phase shift and offset. Suitable resistors and/or capacitors (also for temperature stability) can then be determined from this, so that appropriate resistors and/or capacitors in the secondary winding circuit can achieve a suitable offset adjustment and/or phase adjustment, possibly with improved temperature stability.

Referring now to FIG. 11, alternative embodiments to FIG. 9 will be described in which subsets of secondary windings are formed to provide a differential signal. The same reference symbols between FIGS. 9 and 11 designate the same features, reference being made to the description above for FIG. 9 for a description of these same features.

FIG. 11 shows a detection system 600 which differs from the detection system 400 in FIG. 9 by a detection device 610 . More specifically, sensing device 610 differs from sensing device 410 in FIG. 9 by having a plurality of primary windings 602 and a plurality of secondary windings 604, as will now be described in more detail below.

The plurality of primary windings 602 includes primary windings 602a, 602b, 602c and 602d arranged in series, with the primary windings 602a and 602b being co-wound and arranged in series with one another such that both windings are co-sensing from one to one input terminal of the primary winding 602a applied current are traversed sen. Furthermore, the primary windings 602c and 602d are arranged in series with one another wound in the same direction and wound in opposite directions relative to the primary windings 602a and 602b in series, so that a current applied to the primary winding 602a in the primary windings 602c and 602d relative to the primary windings 602a and 602a 602b flows in the opposite direction. However, a current applied to an input connection of the primary winding 602c flows through the two primary windings 602c and 602d in the same direction.

The plurality of secondary windings 604 includes secondary windings 604a, 604b, 604c and 604d arranged in a like-wound arrangement with respect to one another such that the secondary windings 604a and 604b are wound in the same sense relative to the primary windings 602a and 602b, while the secondary windings 604c and 604d are wound relative to each other are reverse wound on the primary windings 602c and 604d. An interconnection of the secondary windings 604a and 604c in the detection device 610 with the electronic circuit 430 is such that a magnetic flux density (not shown) generated by the primary winding 602a during operation of the detection device in the associated secondary winding 604a generates a current which is applied from the secondary winding 604a to the secondary winding 604c and flows through it in the same direction relative to the current flow in the secondary winding 604a. However, since the windings in the pair of coils consisting of the primary winding 602c and the secondary winding 604c have opposite winding senses to one another, a current flowing in the opposite direction is induced here, so that during operation of the detection device 610 a differential signal is formed between the input and output connection of a subgroup formed by the secondary windings 604a and 604c. Correspondingly, when the secondary windings 604b and 604d are connected in a subgroup of the detection device 610 to the electronic circuit 430, a magnetic flux density (not shown) generated by the primary winding 602b during operation of the detection device generates a current in the associated secondary winding 604b , which is applied from the secondary winding 604b to the secondary winding 604d and flows through it in the same direction relative to the current flow in the secondary winding 604b. However, since the windings in the pair of coils consisting of the primary winding 602d and the secondary winding 604d have opposite winding senses to one another, an oppositely flowing current is induced here during operation of the detection device 610 through the primary winding 602d in the secondary winding 604d, so that a differential signal is generated between the input - and output terminal from this subset of secondary windings 604b and 604d.

Referring to Figure 11, coil pairs of primary winding with associated secondary winding are given by (602a, 604a) and (602b, 604b) and (602c, 604c) and (602d, 604d). Windings in the same direction are only present in the coil pairs (602a, 604a) and (602b, 604b), while the windings in the coil pairs (602c, 604c) and (602d, 604d) are in opposite directions to one another. Furthermore, the plurality of secondary windings 604 is divided into two subgroups [604a, 604c] and [604b, 604d], the windings in a subgroup being arranged in series with one another and being traversed in the same direction by a current applied to the subgroup.

12, further alternative embodiments will now be described to FIGS. 9 and 11 in which subsets of secondary windings are formed to provide a differential signal. The same reference symbols between FIGS. 9, 11 and 12 designate the same features, reference being made to the description above for FIG. 9 for a description of these same features.

FIG. 12 shows a detection system 700 which differs from the detection system 400 in FIG. 9 by a detection device 710 . More specifically, the detection device 710 differs from the detection device 410 in FIG. 9 by a plurality of primary windings 702 and a plurality of secondary windings 704, as will now be described in more detail below.

The plurality of primary windings 702 includes primary windings 702a, 702b, 702c and 702d arranged in series, with the primary windings 702a and 702c being co-wound and arranged in series with one another such that both windings are co-sensing from one to one input terminal of the primary winding 702a applied current are traversed. Furthermore, the primary windings 702b and 702d are arranged in series with one another wound in the same direction and wound in opposite directions relative to the primary windings 702a and 702c in series, so that a current applied to the primary winding 702a in the primary windings 702b and 702d relative to the primary windings 702a and 702a 702c flows in the opposite direction. In this case, however, a current applied to an input connection of the primary winding 702b flows through the two primary windings 702b and 702d in the same direction. The primary windings 702a through 704d are arranged in series and in this arrangement have an alternating winding orientation.

The plurality of secondary windings 704 includes secondary windings 704a, 704b, 704c, and 704d arranged in an alternating winding orientation with respect to one another that corresponds to the alternating winding orientation of the primary windings 702a through 702d such that the secondary windings 704a and 704c are positioned relative to the primary windings 702a and 702c are co-wound, secondary windings 704b and 704d are co-wound relative to primary windings 702b and 704d, and secondary windings 704a and 704c are counter-wound relative to secondary windings 704b and 704d. The secondary windings 704a and 704c in the detection device 710 are connected to the electronic circuit 430 in such a way that a magnetic flux density (not shown) generated by the primary winding 702a during operation of the detection device generates a current in the associated secondary winding 704a of the secondary winding 704a is applied to the secondary winding 704c and flows through it in the same direction relative to the current flow in the secondary winding 704a. However, since the primary winding 702c has an opposite winding sense to the secondary winding 704a, a magnetic field is generated by the primary winding 702c, which induces a current flowing in the opposite direction in the secondary winding 704c, so that during operation of the detection device 710 a differential signal is generated between the input - and output terminal of a subgroup formed by the secondary windings 704a and 704c results. Correspondingly, when the secondary windings 704b and 704d are interconnected in a subgroup of the detection device 710 with the electronic circuit 430, a magnetic flux density (not shown) generated by the primary winding 702b during operation of the detection device must be in the associated Secondary winding 704b generates a current which is applied from the secondary winding 704b to the secondary winding 704d and flows through it in the same direction relative to the current flow in the secondary winding 704b. However, since the windings in the pair of coils consisting of the primary winding 702d and the secondary winding 704d have a winding sense which is oriented in the opposite direction to the winding sense of the secondary winding 704b, here, during operation of the detection device 710, the primary winding 702d in the secondary winding 704d creates a relative to the Coil pair consisting of primary winding 702b and secondary winding 704b is induced by current flowing in opposite directions, so that here too a differential signal results between the input and output connection of this subgroup from the secondary windings 704b and 704d.

Referring to Fig. 12, coil pairs of primary winding with associated secondary winding are given by (702a, 704a) and (702b, 704b) and (702c, 704c) and (702d, 704d), coil pairs (702a, 704a) and ( 702c, 704c) have windings in the same sense as one another and the coil pairs (702b, 704a) and (702d, 704c) have windings in the same sense as one another, which have the opposite winding sense to the coil pairs (702a, 704a) and (702c, 704c) or are in opposite senses to one another . Furthermore, the plurality of secondary windings 704 is divided into two subgroups [704a, 704c] and [704b, 704d], the windings in a subgroup being arranged in series with one another and a current applied to the subgroup flowing through them in the same direction.

Referring to FIG. 11, further illustrative embodiments are described wherein additional coil pairs are added to sensing device 710 to provide symmetrical coupling of end coil pairs formed of windings 702a, 704a, 702d and 704d. This allows an avoidance of an offset in the signals output by the detection device 710 without the need for additional electrical components corresponding to the resistors 406a to 406d and/or corresponding capacitors. On the other hand, additional secondary windings 704e and 704f are provided adjacent to secondary windings 704a and 704d so that secondary windings 704a and 704d are now each sandwiched between two secondary windings (704e and 704b in the case of secondary winding 704a and 704f and 704c in the case of secondary winding 704d). As a result, the expense of providing at least one suitably determined resistor and/or capacitor corresponding to elements 406a to 406d can be avoided at the expense of an additional space requirement for the additional primary windings 702e and 702f. With regard to the secondary windings 704e and 704f, these can be unconnected, so that an active connection of these elements in a secondary winding circuit is not required, but the unconnected secondary windings 704e and 704f are each assigned a primary winding 702e and 702f, which forms a coil pair therewith. With regard to additional primary windings 702e and 702f, these can be arranged in series with the existing primary windings 702a to 702d, so that a winding arrangement with alternating winding senses along the plurality of primary windings 702 is implemented.

The additional windings described with reference to Fig. 12 are not limited to the embodiment shown in Fig. 12 and may also be provided in connection with the embodiments shown in Figs. 9 and 11 as described above. For example, in Fig. 9 a copy of the pair of coils (702f, 704f) from Fig. 12 would be placed to the right of the pair of coils (402a, 404a) in Fig. 9 and to the left of the pair of coils (402d, 404d) in Fig. 9 in accordance with the representation in Fig 12 trained. With respect to FIG. 11, a copy of the pair of coils (702f, 704f) of FIG. 12 would be formed to the right of the pair of coils (602a, 604a) in FIG Coil pair (602d, 604d) would be formed as an additional pair of coils with un connected additional secondary winding.

With regard to FIGS. 9, 11 and 12, various embodiments are described in which primary windings and secondary windings are each coupled and/or interconnected with a specific winding direction or winding sense in such a way that in the primary windings they are assigned to a subgroup of secondary windings are, in each case a magnetic field is generated which induces a voltage in the respective associated secondary winding of the sub-assembly such that a voltage difference occurs at connection ends of the sub-assembly to the electronic circuit 430 from the voltages which are correspondingly induced in the secondary windings.

Referring to FIG. 13, a primary winding circuit 801 is illustrated in accordance with some illustrative embodiments. The primary winding circuit 801 comprises a plurality of primary windings 802 and a capacitor 807 connected to terminals Osz of the electronic circuit 430 already described above. The primary winding circuit 801 may have a resonator circuit having a resonant frequency determined by the plurality of primary windings 802 and the capacitor 807 and operated by the electronic circuit 430 . For example, the electronic circuit 430 comprises an electrical energy source or is capable of providing electrical energy at the terminals Osz, so that the primary winding circuit 801 is suitably supplied with electrical energy. Referring to FIG. 13, the plurality of primary windings 802 includes a parallel connection of primary windings 802a through 802d. For example, the primary windings 802a through 802c are arranged in parallel with the primary winding 802d connected to the terminals.

The primary winding circuit 802 may be provided in a sensing device as described above with reference to any one of FIGS. 9, 11 and 12, with the plurality of primary windings described above with reference and the transmitter structure to any one of FIGS. 9, 11 and 12 is replaced by the plurality of primary windings 802 of FIG. Alternatively, at least one of the primary windings 802a through 802d can be substituted for at least one of the primary windings 402a through 402d in FIG. 9 or at least one of the primary windings 602a through 602d in FIG at least one replaced primary winding is no longer arranged in series in FIGS. 9, 11 and 12, but is arranged in parallel as shown in FIG.

Referring to FIG. 10, there is schematically shown a sectional view through a sensing system 500 that may be used in a rotor position sensor, such as one of the rotor position sensors described with reference to FIGS. 1a, 1b and 2 above, according to some illustrative embodiments. The detection system comprises a detection device 530 with a printed circuit board 501 and a transmitter element 520 with a transmitter structure (not shown). The transmitter structure 520 and the sensing device 510 are spaced from each other by a distance d. For example, d can be in a range from 0.5 mm to 5 mm, preferably in a range from 1 mm to 3 mm, more preferably in a range from 1.5 mm to 2.5 mm.

The printed circuit board 501 includes, as shown schematically in FIG. 10, a primary winding 502 and a secondary winding 504. Optionally, as shown in FIG Shield 540 (eg, a foil or sheet of electrically conductive material that may be connected to a reference potential, such as ground, or unconnected or electrically floating) may be shielded from windings 502 and 504 .

In some illustrative embodiments, circuit board 501 may be multi-layered such that windings 502 and 504, (optional) shield 540, and electronic circuitry 530 may be stacked in various layers. Alternatively, the windings 502 and 504 can be integrated into a first printed circuit board element and the electronic circuit 530 can be integrated into a separate second printed circuit board element, with both conductor Plate elements can be connected to each other via electrical connectors. In this case, an orientation of a normal to a circuit board surface of the first circuit board element, which corresponds to a winding surface of the first circuit board element, can be essentially perpendicular to a surface normal of the second circuit board element. This configuration can be used in an application according to the rotor position sensor in FIG.

In some illustrative embodiments, the electronic circuit 530 can be multi-layered, for example in two levels with circuit levels 530a and 530b. In this case, for example, part of the secondary winding circuit including the resistors and capacitors that are described above in connection with FIGS. 9, 11 and/or 12 can be implemented in the circuit level 530a. The circuit level 530b can correspond to the electronic circuit 430 from at least one of FIGS. 9, 11 and 12, for example.

As shown in FIG. 10, the secondary windings 504 can have a multi-layer design, for example can include winding layers 504-1 and 504-2 or have more layers. The winding layers 504-1 and 504-2 can be spaced apart from each other by, for example, 0.05 mm to 0.2 mm. A distance can be about 100 μm, for example.

Although the primary winding 502 is shown as a single layer in FIG. 10, this is not a limitation and instead the primary winding 502 can be multi-layered. A distance between individual layers can be formed corresponding to a distance between individual winding layers of the secondary winding 504 . The secondary winding 504 and the primary winding 502 may be spaced from each other by, for example, 0.05 mm to 0.2 mm. A distance can be about 100 μm, for example.

The primary winding 502 can be configured in accordance with a primary winding described above. For example, only a single primary winding based on primary winding 502 can be formed in printed circuit board 501 . Alternatively, the primary winding 502 may represent one of a plurality of primary windings. In illustrative examples, and as described above in connection with some illustrative embodiments, primary winding 502 may be paired with secondary winding 504 . For example, in the printed circuit board 501, a plurality of coil pairs can be distributed perpendicularly to the plane of the paper shown in the sectional representation (corresponds to a thickness direction of the printed circuit board 501). A spacing ranging from about 1 mm to about 2 mm may be formed between the primary winding 502 and the (optional) shield 540 . For example, there can be a distance of about 1.7 mm.

A spacing in a range of approximately 0.05 mm to 0.2 mm may be formed between the (optional) shield 540 and the electronic circuitry 530 . The distance can be about 100 μm, for example.

Between individual layers of the electronic circuit 530, a distance ranging from about 0.05 mm to 0.2 mm can be formed. The distance can be about 100 μm, for example.

With respect to the various illustrative embodiments above, windings are described in terms of primary and secondary windings. At least part of these windings can be designed as an air coil, for example. This means that no magnetizable core is provided.

In terms of some illustrative embodiments, "sinusoidal" coils are described above. The term "sinusoidal" also includes a "cosinusoidal" shape, since sine and cosine for an angle cp are known to result from a phase shift of 90° apart: cos cp = sin (cp+90°).

The term "essentially" is intended to express the fact that deviations and modifications are also possible that have little or no effect on the function or the effect to be achieved. Deviations in a range of 50%, such as a maximum of 25% or a maximum of 15% or a maximum of 10% or a maximum of 5% or a maximum of 1% are considered tolerable.

With regard to various embodiments of a detection device with secondary windings connected in subgroups, it can be generally inferred from the above description that primary windings and secondary windings can each be coupled and/or connected with a specific winding sense or winding direction in such a way that in each of the Primary windings, which are assigned to a specific subgroup of secondary windings, a magnetic field is generated in each case, which in turn induces a voltage in the respective assigned secondary winding of this specific subgroup in such a way that at the connection ends of this specific subgroup to the electronic circuit 430, a voltage difference from the voltages occurs, which are correspondingly induced in the individual secondary windings of this particular subgroup. This description discloses various embodiments of a detection device for a position sensor, such as a rotor position sensor or, in general, a position sensor that does not detect a position of a rotor of an electrical machine, but rather a position of any rotating part, such as a part that For example, is flanged to a rotor of an electrical machine via a gear, or a rotating part which rotates only in a limited angular range or continuously.

In some of these illustrative embodiments, this sensing device includes a circuit board, a plurality of primary windings and a plurality of secondary windings, wherein the plurality of primary windings and/or the plurality of secondary windings are integrated into or attached to the circuit board, and each having a primary winding and a Secondary winding are arranged in a pair of coils so that the windings in each pair of coils have a maximum inductive coupling compared to an inductive coupling between tween a winding of this pair of coils and a winding of another pair of coils. In illustrative examples herein, the secondary windings in the printed circuit board can be at least partially connected to one another in a secondary winding circuit with other electrical and/or electronic components integrated into the printed circuit board, or the secondary windings can be provided in the printed circuit board in an unconnected manner, so that the secondary windings can be connected via electrical and / or electronic cal components that are connected to the circuit board from the outside. Additionally or alternatively, the primary windings can be at least partially interconnected with other electrical and/or electronic components integrated into the circuit board, or the primary windings can be provided unconnected in the circuit board, so that the secondary windings are interconnected via electrical and/or electronic components that externally connected to the printed circuit board. This detection device can be made more compact because of the individual coil pairs, since the coil pairs avoid a large-area coil design, so that a corresponding detection device can be made more compact. Furthermore, the avoidance of large-area coils increases the immunity of the detection device to electromagnetic fields, since smaller coil areas are provided, so that fewer interference fields are captured here by the windings. In addition, the coil pairs have improved coupling compared to an arrangement with coils with a large-area coil design, so that less amplification of the measurement signals induced in the secondary windings is required here, which contributes to a compact design of detection devices. This results in the possibility of better adapting the detection device to specified installation spaces fit and/or optimally utilize the given installation space, for example in which further components can be integrated into the given installation space in addition to the detection device. On the other hand, the pairs of coils permit better EMC, since the detection device can emit less radiation due to a compact design.

In other of these embodiments, the windings of each pair of coils may be arranged opposite to each other in a thickness direction of the circuit board, and the pairs of coils may be arranged distributed across the thickness direction. This represents an advantageous design of the coil pairs in the printed circuit board, which on the one hand allows improved coupling between the windings in each coil pair and on the other hand low crosstalk between the coil pairs in a compact design of the printed circuit board.

In further of these embodiments, the secondary windings can be in the form of rectangular coils. In this case, rectangular coils can be provided in a very simple manner with a small coil area. A coil area means an area surrounded by the winding(s) of a winding in a plan view of the winding parallel to the winding axis.

In further such embodiments, the secondary windings in a secondary winding circuit may be divided into a first subgroup and a second subgroup, with only the secondary windings in each subgroup being arranged in series with one another. The secondary winding circuit may further include a first resistor shunted with a first secondary winding from the first subset and a second resistor shunted with a first secondary winding from the second subset. An offset adjustment can be achieved by the first resistor and the second resistor. In sensing devices in which the secondary windings are not evenly spaced over a full circle about an axis, there is an offset in signals output by the secondary windings due to the necessarily asymmetrical placement of the secondary windings about the axis. Alternatively, a capacitor can be provided instead of the first resistor and/or a capacitor can be provided instead of the second resistor. Furthermore, only one of the first resistor and the second resistor can be provided, so that offset compensation is only achieved in one subgroup, with a capacitor being able to be provided instead of this resistor, so that offset compensation is achieved by a capacitor only in one subgroup will. In a specific illustrative example of the fourth embodiment, at least one Resistor and / or at least one capacitor can be integrated into an integrated circuit within the printed circuit board.

In further such embodiments, the secondary winding circuit may further comprise a first capacitor and a second capacitor, wherein the first capacitor is shunted with a second secondary winding from the first subset and the second capacitor is shunted with a second secondary winding from the second subset. In the case of a combination of the first resistor and the first capacitor in the first subgroup and the second resistor and second capacitor in the second subgroup, this can increase temperature stability in each subgroup. Alternatively, only one of the first and second capacitors can be provided, so that improved temperature stability is only achieved in a subgroup. In a special illustrative example of this advantageous development of the fourth specific embodiment, at least one resistor and/or at least one capacitor can be integrated into an integrated circuit within the printed circuit board.

In further such embodiments, the secondary winding circuit may further include an additional resistor or capacitor interposed between a secondary winding from the first subset and a secondary winding from the second subset. This can also be an alternative to the fifth embodiment (“alternative fifth embodiment”), the additional resistor or additional capacitor also being provided instead of the first and/or second resistor (or capacitor) or instead of both resistors (or capacitors). . A phase adjustment between the individual subgroups can be achieved with the additional resistor or additional capacitor. In this case, a phase shift is compensated for, which occurs because the windings have different levels of coupling to the windings of adjacent pairs of coils. Here, too, improved temperature stability can also be achieved by a combination of a capacitor and a resistor, each of which is arranged between a winding of the first subgroup and a winding of the second subgroup. In a special illustrative example of this other advantageous refinement of the fourth embodiment, at least one resistor and/or at least one capacitor can be integrated into an integrated circuit within the printed circuit board.

In further of these embodiments, the first subgroup and the second subgroup can each have two secondary windings with opposite winding senses. Thereby an output of differential output signals for the subgroups in the Secondary winding circuit provided so that interference signals can be compensated, for example, on the secondary winding conditions.

In the context of the described embodiments, at least one of the primary windings and at least one secondary winding can be formed as an air coil, as described above.

Although applications with regard to a rotor position sensor are described with reference to the figures, this does not represent a limitation. Instead of a rotor position sensor, the inventions can be applied to a position sensor that does not directly indicate a position of a rotor of an electrical machine, but a position of any rotating Part detected, such as a part that is flanged, for example, via a gear to a rotor of an electric machine, or a rotating part, which rotates only in a limited angular range or continuously, such as any rotating actuator.

Claims

Expectations

A sensing device for a position encoder, comprising: a primary winding, and a secondary winding circuit having a plurality of secondary windings inductively coupled to the primary winding, the plurality of secondary windings as two sinusoidal coils (220; 320) each with a center tap (M1; M2 ) are trained.

2. Detection device according to claim 1, wherein the primary winding is formed as a rectangular coil surrounding the plurality of secondary windings in plan view.

3. The detection device as claimed in claim 1 or 2, wherein the plurality of secondary windings has a first subgroup of at least two secondary windings arranged in a row and a second subgroup of at least two secondary windings arranged in a row.

4. Sensing device according to claim 3, further comprising a resistor or capacitor which is arranged between a secondary winding from the first sub-group and a secondary winding from the second sub-group.

5. The sensing device of claim 3 or 4, wherein the secondary winding circuit further comprises a first resistor connected in parallel with a first secondary winding (222a, 222b; 322a, 322b) from the first subset and a second resistor connected in parallel with a first secondary winding from the second subgroup is arranged.

6. Detection device according to one of claims 1 to 5, wherein the primary winding and the secondary winding circuit are integrated together in a printed circuit board.

7. Detection device (100; 410; 510; 610; 710) for a position encoder, comprising: at least one primary winding (110; 402; 502; 602; 702), and a secondary winding circuit with a plurality of secondary windings (120a, 120b; 220; 320; 504; 604; 704) inductively coupled to the at least one primary winding (110; 402; 502; 602; 702), the plurality of secondary windings (120a, 120b; 220; 320; 404; 504; 604; 704) a first subgroup of at least two secondary windings (222a, 222b; 322a, 322b; 404a, 404c; 504a, 504c; 604a, 604c; 704a, 704c) arranged in a row with one another and a second subgroup (404b, 404d; 504b, 504d; 604b, 604d; 704b, 704d) of at least two secondary windings arranged in series with one another, and wherein the secondary winding circuit further comprises a first resistor or capacitor (408a-408d) connected between a secondary winding from the first subgroup and a secondary winding from the second sub rgroup is arranged or which is arranged in parallel with a first secondary winding from the first subgroup or the second subgroup.

8. The sensing device of claim 7, wherein the at least one primary winding and the secondary winding circuit are integrated together into a printed circuit board.

9. Detection device (510) according to claim 8, wherein a number of primary windings (502) and a number of secondary windings (504) is the same and in the printed circuit board (501) a primary winding (502) is tailored to exactly one secondary winding (504).

The sensing device (100; 410; 510; 610; 710) of any one of claims 7 to 9, wherein the secondary winding circuit further comprises an additional resistor or capacitor connected between two other secondary windings each having one of the first subset and one of the second Subgroup is arranged.

11. Detection device according to one of claims 7 to 10, wherein the plurality of secondary windings as two sinusoidal coils (220; 320) each with a center tap (M1; M2) are formed and only one primary winding is provided, which is formed as a rectangular coil and surrounds the secondary windings in plan view.

12. Detection device according to one of claims 3 to 11, wherein the secondary windings (22a, 22b; 322a, 322b) in each subgroup are connected in the secondary winding circuit in such a way that they are connected relative to the or the at least one primary winding such that during operation of the detection device a Differential signal is provided by each subgroup.

The sensing device (100; 410; 510; 610; 710) of any one of claims 3 to 12, wherein the secondary winding circuit further comprises a first capacitor and a second capacitor, the first capacitor in parallel with a second secondary winding from the first subset and the second capacitor is arranged in parallel with a second secondary winding from the second subgroup.

14. A detection system, comprising: a detection device according to any one of claims 1 to 13, and a transmitter element which is arranged rotatably relative to the detection device, wherein the transmitter element has a transmitter structure which is formed from an electrically conductive material.