DE102023102164B4 - Secondary coil arrangement for an inductive encoder - Google Patents

Abstract

The invention relates to a secondary coil arrangement (1) for an inductive encoder (10), wherein the secondary coil arrangement (1) has a plurality of sub-segments (2.1, 2.2) of a sine function formed as conductor tracks on a circuit board and electrically connected to one another without crossing and/or a plurality of sub-segments (3.1, 3.2) of a cosine function formed as conductor tracks on the circuit board and electrically connected to one another without crossing, wherein these sub-segments (2.1, 2.2, 3.1, 3.2) simulate the sine function or the cosine function in sections with periodic interruptions (3.1, 3.2).

Description

The invention relates to a secondary coil arrangement for an inductive encoder.

Inductive encoders are used, for example, for path and angle measurements that are subject to strong environmental interference. Such inductive encoders can be constructed in a similar way to a transformer with a primary coil that feeds in and a secondary coil on which an induced voltage is measured. The way the inductive encoder works depends heavily on the geometry of the primary coil and the secondary coil. The aim is in particular to design the geometry of the coils in such a way that sinusoidal signals with high quality are generated and can be evaluated on the secondary coil. For example, circuit board material is used to create the geometry of the coils of inductive encoders. Vias are technically feasible on the circuit board material and thus crossings are also possible, which makes the design of the coil easier. However, vias have a negative effect on the signal quality and prevent a significant shortening of the period length.

In the current state of the art, the secondary coils are usually designed to be sinusoidal and cosinusoidal. When modulated with a target designed to match the period length, sinusoidal signals and cosinusoidal signals are produced. These enable absolute angle evaluation using the arctangent function over a period.

Such coil geometries result in intersections that require the use of vias. However, this has the disadvantage that the number of periods and the associated resolution of the encoder is limited to its maximum due to the increased space required by the vias. The use of multiple layers in the circuit board material also causes offset and linearity shifts, as the target is not always the same distance from the secondary coil. A voltage is also induced in the copper surfaces of the vias, which can have a negative influence on the measurement signal.

• - einer Leiterplatte, auf der eine Erregerleiterbahn und mindestens eine Empfängerleiterbahn aufgebracht sind, wobei die mindestens eine Empfängerleiterbahn einen ersten Teilabschnitt aufweist, der in einer ersten Ebene verläuft, und einen zweiten Teilabschnitt aufweist, der in einer zweiten Ebene verläuft,
• - einem Teilungselement, welches relativ zur Leiterplatte drehbar ist und eine Teilungsspur umfasst, die aus alternierend angeordneten, elektrisch leitfähigen und nichtleitfähigen Teilungsbereichen besteht, wobei die mindestens eine Empfängerleiterbahn innerhalb einer Umdrehung relativ zum Teilungselement eine ungerade Anzahl von Signalperioden liefert, wobei der erste Teilabschnitt der mindestens einen Empfängerleiterbahn eine größere Länge aufweist als der zweite Teilabschnitt.

DE 103 20 990 A1 describes an inductive angle sensor consisting of

• - a printed circuit board on which an excitation conductor track and at least one receiver conductor track are applied, wherein the at least one receiver conductor track has a first partial section which runs in a first plane and a second partial section which runs in a second plane,
• - a dividing element which is rotatable relative to the circuit board and comprises a dividing track which consists of alternately arranged, electrically conductive and non-conductive dividing regions, wherein the at least one receiver conductor track delivers an odd number of signal periods within one revolution relative to the dividing element, wherein the first subsection of the at least one receiver conductor track has a greater length than the second subsection.

EN 102021 121 052 A1 describes a secondary coil arrangement for an inductive encoder system with a plurality of secondary coils, each secondary coil having a secondary coil conductor track, the secondary coil conductor tracks being arranged without crossing on a conductor carrier. Furthermore, an inductive encoder system is described with at least one primary coil having a modulation region, and at least one receiver track having at least one receiver line set and an above-mentioned secondary coil arrangement, the secondary coil arrangement being arranged within the modulation region.

EN 10 2004 026 311 A1 describes a position sensor comprising at least two transmitter coils and one receiver coil and a division structure arranged to be movable relative to the coils, wherein the division structure, transmitter coil windings and receiver coil winding are arranged essentially in planes that are parallel to one another or at least quasi-planes, wherein the transmitter coils and receiver coil are inductively and/or capacitively coupled and the strength of the coupling can be changed depending on the position and/or orientation of the division structure relative to the coils, wherein each transmitter coil winding encloses at least two regions that generate different magnetic flux directions relative to one another, wherein the regions of the first and second transmitter coil windings are arranged to overlap, the receiver coil winding is shaped such that its conductor loop and/or winding essentially follows the envelope of all regions of the transmitter coil windings.

The invention is based on the object of specifying a novel secondary coil arrangement for an inductive encoder.

The object is achieved according to the invention by a secondary coil arrangement for an inductive encoder with the features of claim 1.

Advantageous embodiments of the invention are the subject of the subclaims.

A secondary coil arrangement according to the invention has a plurality of sub-segments of a sine function, which are designed as conductor tracks on a circuit board and are electrically connected to one another without crossing, and a plurality of sub-segments of a cosine function, which are designed as conductor tracks on the circuit board and are electrically connected to one another without crossing. These sub-segments reproduce the sine function or the cosine function in sections with periodic interruptions.

The sections of the sine function and/or the cosine function formed in this way can form a meander-like shape. The electrical signal generated with this secondary coil arrangement has a high quality.

In one embodiment, the subsegments assigned to the sine function intervene in the interruptions of the cosine function and the subsegments assigned to the cosine function intervene in the interruptions of the sine function.

In this way, the subsegments are nested with each other, thus reducing connecting lines and reducing the slope at shorter period lengths.

The solution according to the invention provides meander-like, crossing-free and through-hole-free coil geometries, which have the advantage of being variable in terms of manufacturing technology in the choice of materials.

The geometry of the coils according to the invention makes it possible to dispense with through-holes, since these are no longer necessary for the inductive encoder to function with the geometry according to the invention. In this way, the resolution and size of the encoder can be scaled, which is only dependent on the structure width of the conductor tracks. This allows a significantly higher resolution and the use of other carrier materials in production. If the entire geometry of the secondary coils is realized on one layer, the target always has the same distance from the secondary coils, thus preventing linearity shifts and amplitude jumps.

According to the invention, at least one or each of the sub-segments is designed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum or from its maximum to the subsequent minimum.

In one embodiment, for the sine function along a longitudinal direction or rotation direction of the encoder, a plurality of pairs of sub-segments each consisting of a first sub-segment and a second sub-segment are arranged periodically with a distance of, for example, 4π, based on a period of this sine function, in at least one plane or at least one circle. The second sub-segment of the pair is arranged with its minimum at the position of the maximum of the first sub-segment in the longitudinal direction or rotation direction or with its maximum at the position of the minimum of the first sub-segment in the longitudinal direction or rotation direction. The maxima or minima of the two sub-segments of the pair in one of the planes or one of the circles are connected to each other by a conductor track segment, the next pair of sub-segments for the sine function following at a distance of 2π from the end of the previous pair considered here or 4π from the beginning of the previous pair considered here, the minimum or maximum of the second sub-segment of the or each pair in one of the planes or one of the circles being connected to the minimum or maximum of the first sub-segment of the respective subsequent pair by a conductor track segment.

In one embodiment, for the cosine function along a longitudinal direction or rotation direction of the encoder, a plurality of pairs of sub-segments each consisting of a first sub-segment and a second sub-segment are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, in at least one plane or at least one circle. The second sub-segment of the pair is arranged with its minimum at the position of the maximum of the first sub-segment in the longitudinal direction or rotation direction, or with its maximum at the position of the minimum of the first sub-segment in the longitudinal direction or rotation direction. The maxima or minima of the two sub-segments of the pair in one of the planes or one of the circles are connected to one another by a conductor track segment. The next pair of subsegments for the cosine function follows at a distance of 2π from the end of the previous pair considered here or 4π from the beginning of the previous pair considered here, whereby the maximum or minimum of the second subsegment of the or each pair in one of the planes or one of the circles is connected to the maximum or minimum of the first subsegment of the respective subsequent pair by a conductor track segment.

beträgt.In one embodiment, one or more pairs or all pairs of subsegments for the cosine function overlap in their position with a pair of sub-segments for the sine function, whereby the overlap in particular $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

amounts.

In one embodiment, the conductor track segment runs in the longitudinal direction or rotational direction. Otherwise, an additional change in area would be the result and, as a result, a distortion of the signal.

In one embodiment, the conductor track segment is arranged offset by a distance in a transverse direction or radial direction from the respective maxima or minima.

In one embodiment, at least two planes parallel to one another in the longitudinal direction or circles concentric in the direction of rotation are provided, in each of which a plurality of pairs of sub-segments for the sine function and/or cosine function are arranged, wherein corresponding sub-segments in adjacent planes or circles are connected in series with one another, wherein the minima or maxima of the two sub-segments of a pair in one of the planes or in one of the circles are connected to one another by a conductor track segment, wherein the maximum or minimum of the second sub-segment of one or each pair in another plane or another circle is connected to the maximum or minimum of the first sub-segment of the respective subsequent pair in the same plane or in the same circle by a conductor track segment.

In one embodiment, in each plane or in each circle, only partial segments formed as at least approximately S-shaped sections of a sine function or cosine function from its minimum to the subsequent maximum are arranged, or only partial segments formed as at least approximately S-shaped sections of a sine function or cosine function from its maximum to the subsequent minimum are arranged. Only partial segments formed in the same way are therefore arranged within a plane or a circle.

In one embodiment, at least two planes parallel to one another in the longitudinal direction or circles concentric in the direction of rotation are provided, wherein in at least one of the planes or in at least one of the circles only partial segments are arranged which are designed as at least approximately S-shaped sections of a sine function or cosine function from its minimum to the subsequent maximum, wherein in at least one other of the planes or in at least one other of the circles only partial segments are arranged which are designed as at least approximately S-shaped sections of a sine function or cosine function from its maximum to the subsequent minimum. If there is more than one plane or more than one circle, different partial segments can be arranged in one circle than in another of the circles. In other embodiments, however, similar partial segments can also be arranged in several or all planes or circles.

The conductor tracks can all be arranged in one layer on the circuit board.

According to one aspect of the present invention, an inductive encoder is proposed, comprising a primary coil, a secondary coil arrangement as described above and a target movable relative to the secondary coil arrangement for field weakening of an alternating magnetic field generated by the primary coil when subjected to an alternating voltage at the secondary coil arrangement.

Embodiments of the invention are explained in more detail below with reference to drawings.

• 1 einen induktiven Encoder mit einer Sekundärspulenanordnung,
• 2 eine schematische Ansicht einer durch Feldschwächung mittels eines Targets modulierten, in der Sekundärspulenanordnung induzierten Spannung,
• 3 eine schematische Ansicht eines rotatorischen induktiven Encoders,
• 4 eine schematische Ansicht einer weiteren Ausführungsform eines rotatorischen induktiven Encoders,
• 5 eine schematische Ansicht mehrerer sinusförmiger Teilsegmente mit unterschiedlicher Periodenlänge,
• 6 eine schematische Ansicht einer weiteren Ausführungsform eines linearen induktiven Encoders,
• 7 eine schematische Ansicht einer weiteren Ausführungsform eines linearen induktiven Encoders,
• 8 eine schematische Ansicht einer weiteren Ausführungsform eines rotatorischen induktiven Encoders, und
• 9 eine schematische Ansicht einer weiteren Ausführungsform eines rotatorischen induktiven Encoders.

Shown here:

• 1 an inductive encoder with a secondary coil arrangement,
• 2 a schematic view of a voltage induced in the secondary coil arrangement modulated by field weakening by means of a target,
• 3 a schematic view of a rotary inductive encoder,
• 4 a schematic view of another embodiment of a rotary inductive encoder,
• 5 a schematic view of several sinusoidal sub-segments with different period lengths,
• 6 a schematic view of another embodiment of a linear inductive encoder,
• 7 a schematic view of another embodiment of a linear inductive encoder,
• 8 a schematic view of another embodiment of a rotary inductive encoder, and
• 9 a schematic view of another embodiment of a rotary inductive encoder.

Corresponding parts are provided with the same reference numerals in all figures.

1 shows an embodiment of a secondary coil arrangement 1 of an inductive encoder 10.

According to the present invention, instead of the secondary coils with sinusoidal and cosinusoidal geometry that are usual in the prior art, a meandering secondary coil arrangement 1 is proposed, which has a plurality of sub-segments 2.1, 2.2 of a sine function designed as conductor tracks and a plurality of sub-segments 3.1, 3.2 of a cosine function with a length of 180° or π in relation to a period length of the sine function or cosine function under consideration of 2π. These sub-segments 2.1, 2.2 or 3.1, 3.2 are connected to one another over two periods in such a way that no crossings occur. These sub-segments 2.1, 2.2 or 3.1, 3.2 span an area that is used for modulation with a target 4. This surface is penetrated by an alternating field generated by a primary coil 11, for example by applying a sinusoidal signal to the primary coil 11. An alternating voltage is thus induced in the secondary coil arrangement 1, which is referred to as a carrier.

bis $+\frac{\mathrm{\pi }}{2}$

bei der Sinusfunktion und π bis 2π bei der Cosinusfunktion) ausgebildet. Dabei sind für die Sinusfunktion entlang einer Längsrichtung x des Encoders 10 eine Mehrzahl von Paaren von Teilsegmenten 2.1, 2.2 periodisch mit einem Abstand von beispielsweise 4π, bezogen auf eine Periodendauer dieser Sinusfunktion, angeordnet, wobei ein erstes Teilsegment 2.1 eines Paars mit seinem Minimum bei der Position $-\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{\pi }}{2}$

2 2 angeordnet ist, wobei ein zweites Teilsegment 2.2 des Paars mit seinem Minimum bei der Position $\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{3\pi }}{2}$

angeordnet ist. Dabei sind die Maxima der beiden Teilsegmente 2.1, 2.2 des Paars miteinander durch ein in Längsrichtung x verlaufendes Leiterbahnsegment 5 verbunden. Das nächste Paar folgt in einem Abstand von 2π ab dem Ende des vorherigen Paars oder 4π ab dem Beginn des vorherigen Paars, das heißt ein erstes Teilsegment 2.1 des nächsten Paars ist mit seinem Minimum bei der Position $\frac{\mathrm{7\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{9\pi }}{2}$

angeordnet, wobei ein zweites Teilsegment 2.2 des nächsten Paars mit seinem Minimum bei der Position $\frac{\mathrm{9\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{11\pi }}{2}$

angeordnet ist. Das Minimum des zweiten Teilsegments 2.2 eines oder jedes Paars ist mit dem Minimum des ersten Teilsegments 2.1 des jeweils nachfolgenden Paars durch ein in Längsrichtung x verlaufendes Leiterbahnsegment 6 verbunden.According to the invention, each of the sub-segments 2.1, 2.2 or 3.1, 3.2 is designed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum (i.e. $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

until $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

for the sine function and π to 2π for the cosine function). For the sine function, a plurality of pairs of sub-segments 2.1, 2.2 are arranged periodically along a longitudinal direction x of the encoder 10 with a distance of, for example, 4π, based on a period of this sine function, with a first sub-segment 2.1 of a pair having its minimum at the position $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

2 2, wherein a second sub-segment 2.2 of the pair has its minimum at the position $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">3\pi </figure-callout>}}{2}$

The maxima of the two sub-segments 2.1, 2.2 of the pair are connected to each other by a conductor track segment 5 running in the longitudinal direction x. The next pair follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 2.1 of the next pair has its minimum at the position $\frac{\mathrm{7\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="9\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">9\pi </figure-callout>}}{2}$

arranged, with a second sub-segment 2.2 of the next pair having its minimum at the position $\frac{\mathrm{9\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="11\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">11\pi </figure-callout>}}{2}$

The minimum of the second sub-segment 2.2 of one or each pair is connected to the minimum of the first sub-segment 2.1 of the respective subsequent pair by a conductor track segment 6 running in the longitudinal direction x.

The conductor track segment 5, 6 can be arranged offset from the respective maxima or minima by a particularly small distance in a transverse direction y, i.e. transverse to the longitudinal direction x. However, this is not absolutely necessary.

Similarly, for the cosine function along the longitudinal direction x of the encoder 10, a plurality of pairs of sub-segments 3.1, 3.2 are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, wherein a first sub-segment 3.1 of a pair is arranged with its minimum at position π and its maximum at position 2π, wherein a second sub-segment 3.2 of the pair is arranged with its minimum at position 2π and its maximum at position 3π. The minima of the two sub-segments 3.1, 3.2 of the pair are connected to one another by a conductor track segment 7 running in the longitudinal direction x. The next pair follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 3.1 of the next pair is arranged with its minimum at position 5π and its maximum at position 6π, with a second sub-segment 3.2 of the next pair being arranged with its minimum at position 6π and its maximum at position 7π. The maximum of the second sub-segment 3.2 of one or each pair is connected to the maximum of the first sub-segment 3.1 of the respective subsequent pair by a conductor track segment 8 running in the longitudinal direction x.

In this case, the conductor track segment 7, 8 can be arranged offset in the transverse direction y from the respective maxima or minima by a particularly small distance.

In this way, the sine functions and the cosine functions of the secondary coil arrangement 1 are interlocked without any crossing points occurring between the conductor tracks.

The encoder 10 further comprises one or more targets 4 movable in the longitudinal direction x, preferably made of a metal with a permeability <= 1. In the case of a metal or a magnet izable or magnetized material, in particular a ferromagnetic material with high permeability, the operating principle of the target 4 is reversed.

The target 4 can have a length of at least about π (corresponding to 180°) in the longitudinal direction x. With a shorter target 4, the signal amplitude is significantly reduced. With a length of the target 4 of 250° to 270°, the greatest amplitude can be achieved. In the transverse direction y, the target 4 can have a width that exceeds the distance between the minimum and the maximum of each sub-segment 2.1, 2.2 or 3.1, 3.2. For example, the width of the target 4 can be selected such that it covers the sub-segments 2.1, 2.2, 3.1, 3.2 and at least 50% of the primary coil 11. Preferably, a plurality of targets 4 can be provided, which are arranged periodically one after the other with a distance of π from one another or with a period length of 2π.

When the target 4 passes over the secondary coil arrangement 1, a current flow results through the sub-segments 2.1, 2.2 of the sine function and/or sub-segments 3.1, 3.2 of the cosine function of the secondary coil arrangement 1, in which the sub-segments 2.1, 2.2 or 3.1, 3.2 are alternately passed through in electrically positive and negative directions, so that a sine function or cosine function is obtained.

Ui

induzierte Spannung

N

Faktor für Windungszahl der Spule

B

magnetische Flussdichte

t

Zeit

A

Fläche

In the following, the functionality of the encoder 10 is derived using the law of induction: $$U_i=-N\cdot \frac{\mathrm{\Delta }B}{\mathrm{\Delta }t}\cdot A$$

Wow

induced voltage

N

Factor for number of turns of the coil

B

magnetic flux density

t

Time

A

Area

U

Spannung

Û

Amplitude

ω

Kreisfrequenz

The primary coil 11 is supplied with a sinusoidal alternating voltage: $$U\left(t\right)=\widehat{U}\cdot \text{sin}\left(\mathrm{\omega }\cdot \mathrm{\tau }\right)$$

U

Tension

Û

amplitude

ω

Angular frequency

This results in a harmonic change of the magnetic flux density B with the angular frequency ω: $$B\left(t\right)=\widehat{B}\cdot \text{cos}\left(\mathrm{\omega }\cdot \text{t}\right)$$

mit Anwendung der Kettenregel der Differenzialrechnung: $${\text{U}}_i=-N\cdot \widehat{B}\cdot \left(-\text{sin}\left(\mathrm{\omega }\cdot \text{t}\right)\ast \mathrm{\omega }\right)\cdot \mathrm{{\rm A}}$$

$${\text{U}}_i=N\cdot B\cdot \mathrm{\omega }\cdot \mathrm{{\rm A}}\cdot \text{sin}\left(\mathrm{\omega }\cdot \text{t}\right)$$

Ist kein Target 4 zur Feldschwächung über der Sekundärspulenanordnung 1 vorhanden, so ist die induzierte Spannung U_i maximal und es findet keine Modulation statt. An der Sekundärspulenanordnung 1 wird somit eine sinusförmige Wechselspannung als induzierte Spannung U_i gemessen.Inserted into the law of induction, the following relationship results: $${\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="DE102023102164B4\_0060.png"\; state="\{\{state\}\}">U</figure-callout>}}_1=-N\cdot \frac{d\left(\widehat{B}\cdot cOs\left(\mathrm{\omega }\cdot \text{t}\right)\right)}{dt}\cdot A$$

using the chain rule of differential calculus: $${\text{U}}_i=-N\cdot \widehat{B}\cdot \left(-\text{sin}\left(\mathrm{\omega }\cdot \text{t}\right)\ast \mathrm{\omega }\right)\cdot \mathrm{A}$$

$${\text{U}}_i=N\cdot B\cdot \mathrm{\omega }\cdot \mathrm{A}\cdot \text{sin}\left(\mathrm{\omega }\cdot \text{t}\right)$$

If there is no target 4 for field weakening above the secondary coil arrangement 1, the induced voltage U _i is maximum and no modulation takes place. A sinusoidal alternating voltage is thus measured at the secondary coil arrangement 1 as the induced voltage U _i .

However, if a target 4 is placed above the secondary coil arrangement 1, the alternating field beneath the target 4 is weakened. This results in a change in the size of the area penetrated by the alternating field. If one refers to the previously derived formula for the induced voltage U _i , it can be seen that a change in the penetrated area has a direct influence on the induced voltage U _i . Due to the shape of the area spanned by the sub-segments 2.1, 2.2 or 3.1, 3.2 and the target 4 which is perpendicular to the longitudinal direction x, a linear movement of the target 4 results in a sinusoidal amplitude curve of the induced voltage U _i .

If the area A penetrated by the alternating field decreases due to the moving target 4, the change in area is negative and the induced voltage U _i is therefore of reversed polarity. This creates the negative sine half-wave and vice versa the positive one.

2 is a schematic view of the induced voltage U _i modulated by the field weakening by means of the target 4 over time t.

The principle of this solution can be applied to linear as well as rotary inductive encoders. 3 is a schematic view of a rotary inductive encoder 10 with, for example, 32 periods per revolution, i.e. over 360°. The above 1 The relationships described above also apply to 3 Application.

Therefore, a meandering secondary coil arrangement 1 is also provided here, which has a large number of partial segments 2.1, 2.2 of a sine function designed as conductor tracks and a large number of partial segments 3.1, 3.2 of a cosine function, each with a length of 180° or π with respect to the period length of the sine function or cosine function under consideration of 2π. These partial segments 2.1, 2.2 or 3.1, 3.2 are connected to one another over two periods in such a way that no crossings occur. These partial segments 2.1, 2.2 or 3.1, 3.2 span an area that is used for modulation with a target 4. This area is penetrated by an alternating field generated by a primary coil 11. An alternating voltage is thus induced in the secondary coil arrangement 1, which is referred to as a carrier.

bis $+\frac{\mathrm{\pi }}{2}$

bei der Sinusfunktion und π bis 2π bei der Cosinusfunktion) ausgebildet. Dabei sind für die Sinusfunktion entlang einer Rotationsrichtung d des Encoders 10 eine Mehrzahl von Paaren von Teilsegmenten 2.1, 2.2 periodisch mit einem Abstand von beispielsweise 4π, bezogen auf eine Periodendauer dieser Sinusfunktion, angeordnet, wobei ein erstes Teilsegment 2.1 eines Paars mit seinem Minimum bei der Winkelposition $-\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{\pi }}{2}$

angeordnet ist, wobei ein zweites Teilsegment 2.2 des Paars mit seinem Minimum bei der Winkelposition $\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{3\pi }}{2}$

angeordnet ist. Dabei sind die Maxima der beiden Teilsegmente 2.1, 2.2 des Paars miteinander durch ein in Rotationsrichtung d verlaufendes Leiterbahnsegment 5 verbunden. Das nächste Paar folgt in einem Abstand von 2π ab dem Ende des vorherigen Paars oder 4π ab dem Beginn des vorherigen Paars, das heißt ein erstes Teilsegment 2.1 des nächsten Paars ist mit seinem Minimum bei der Winkelposition $\frac{\mathrm{7\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{9\pi }}{2}$

angeordnet, wobei ein zweites Teilsegment 2.2 des nächsten Paars mit seinem Minimum bei der Winkelposition $\frac{\mathrm{9\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{11\pi }}{2}$

angeordnet ist. Das Minimum des zweiten Teilsegments 2.2 eines oder jedes Paars ist mit dem Minimum des ersten Teilsegments 2.1 des jeweils nachfolgenden Paars durch ein in Rotationsrichtung d verlaufendes Leiterbahnsegment 6 verbunden.Each of the sub-segments 2.1, 2.2 or 3.1, 3.2 is designed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum (i.e. $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

until $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

for the sine function and π to 2π for the cosine function). For the sine function, a plurality of pairs of sub-segments 2.1, 2.2 are arranged periodically along a direction of rotation d of the encoder 10 with a distance of, for example, 4π, based on a period of this sine function, with a first sub-segment 2.1 of a pair having its minimum at the angular position $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

wherein a second sub-segment 2.2 of the pair has its minimum at the angular position $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">3\pi </figure-callout>}}{2}$

The maxima of the two sub-segments 2.1, 2.2 of the pair are connected to each other by a conductor track segment 5 running in the direction of rotation d. The next pair follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 2.1 of the next pair has its minimum at the angular position $\frac{\mathrm{7\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="9\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">9\pi </figure-callout>}}{2}$

arranged, with a second sub-segment 2.2 of the next pair having its minimum at the angular position $\frac{\mathrm{9\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="11\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">11\pi </figure-callout>}}{2}$

The minimum of the second sub-segment 2.2 of one or each pair is connected to the minimum of the first sub-segment 2.1 of the respective subsequent pair by a conductor track segment 6 running in the direction of rotation d.

In this case, the conductor track segment 5, 6 can be arranged offset from the respective maxima or minima by a particularly small distance in a radial direction r, i.e. at right angles to the direction of rotation d.

Similarly, for the cosine function along the direction of rotation d of the encoder 10, a plurality of pairs of sub-segments 3.1, 3.2 are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, wherein a first sub-segment 3.1 of a pair is arranged with its minimum at the angular position π and its maximum at the angular position 2π, wherein a second sub-segment 3.2 of the pair is arranged with its minimum at the angular position 2π and its maximum at the angular position 3π. The minima of the two sub-segments 3.1, 3.2 of the pair are connected to one another by a conductor track segment 7 running in the direction of rotation d. The next pair follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 3.1 of the next pair is arranged with its minimum at the angular position 5π and its maximum at the angular position 6π, with a second sub-segment 3.2 of the next pair being arranged with its minimum at the angular position 6π and its maximum at the angular position 7π. The maximum of the second sub-segment 3.2 of one or each pair is connected to the maximum of the first sub-segment 3.1 of the respective subsequent pair by a conductor track segment 8 running in the direction of rotation d.

In this case, the conductor track segment 7, 8 can be arranged offset in the radial direction r from the respective maxima or minima by a particularly small distance.

In this way, the sine functions and the cosine functions of the secondary coil arrangement 1 are interlocked without any crossing points occurring between the conductor tracks.

The encoder 10 further comprises one or more targets 4 which are movable in the direction of rotation d and which are made, for example, of a metal and/or a magnetizable or magnetized material, in particular a ferromagnetic material of high permeability.

The target 4 or each of the targets 4 can extend in the direction of rotation d over an angle of approximately π. In the radial direction r, the target 4 can have a width which extends over the distance between the minimum and the maximum of each sub-segment 2.1, 2.2 or 3.1, 3.2. In particular, a plurality of targets 4 can be provided which are arranged periodically one after the other with a distance of π between them or with a period length of 2π over the circumference.

The target 4 can also be longer than 180° elec. Targets 4 of different lengths were measured using a linear design. The largest signal amplitude was achieved with 250° elec.

As well as from 3 As can be seen, the secondary coil arrangement 1 has no crossings, so that there is no need to use vias.

4 is a schematic view of another embodiment of a rotary inductive encoder 10 with a multiple secondary coil arrangement 1 and a division into 64 periods over 360°.

The above 3 The relationships described above also apply to 4 Application.

Therefore, a meandering secondary coil arrangement 1 is also provided here, which has a large number of partial segments 2.1, 2.2 of a sine function designed as conductor tracks and a large number of partial segments 3.1, 3.2 of a cosine function, each with a length of 180° or π with respect to the period length of the sine function or cosine function under consideration of 2π. These partial segments 2.1, 2.2 or 3.1, 3.2 are connected to one another over two periods in such a way that no crossings occur. These partial segments 2.1, 2.2 or 3.1, 3.2 span an area that is used for modulation with a target 4. This area is penetrated by an alternating field generated by a primary coil 11. An alternating voltage is thus induced in the secondary coil arrangement 1, which is referred to as a carrier.

bis $+\frac{\mathrm{\pi }}{2}$

bei der Sinusfunktion und π bis 2π bei der Cosinusfunktion) ausgebildet. Dabei sind für die Sinusfunktion entlang einer Rotationsrichtung d des Encoders 10 eine Mehrzahl von Paaren von Teilsegmenten 2.1, 2.2 periodisch mit einem Abstand von beispielsweise 4π, bezogen auf eine Periodendauer dieser Sinusfunktion, in einem äußeren Kreis 12 und einem konzentrisch im äußeren Kreis 12 angeordneten inneren Kreis 13 angeordnet, wobei in jedem der Kreise 12, 13 jeweils ein erstes Teilsegment 2.1 eines Paars mit seinem Minimum bei der Winkelposition $-\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{\pi }}{2}$

angeordnet ist, wobei in jedem der Kreise 12, 13 jeweils ein zweites Teilsegment 2.2 des Paars mit seinem Minimum bei der Winkelposition $\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{3\pi }}{2}$

angeordnet ist. Dabei sind die beiden ersten Teilsegmente 2.1 der Kreise 12, 13 zueinander in Reihe geschaltet und die beiden zweiten Teilsegmente 2.2 der Kreise 12, 13 zueinander in Reihe geschaltet und die Minima der beiden Teilsegmente 2.1, 2.2 des Paars im inneren Kreis 13 miteinander durch ein in Rotationsrichtung d verlaufendes Leiterbahnsegment 5 verbunden. Das nächste in gleicher Weise gebildete Paar folgt in einem Abstand von 2π ab dem Ende des vorherigen Paars oder 4π ab dem Beginn des vorherigen Paars in jedem der Kreise 12, 13, das heißt ein erstes Teilsegment 2.1 des nächsten Paars in jedem der Kreise 12, 13 ist mit seinem Minimum jeweils bei der Winkelposition $\frac{\mathrm{7\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{9\pi }}{2}$

angeordnet, wobei ein zweites Teilsegment 2.2 des nächsten Paars in jedem der Kreise 12, 13 jeweils mit seinem Minimum bei der Winkelposition $\frac{\mathrm{9\pi }}{2}$

und seinem Maximum bei der Winkelposition $+\frac{\mathrm{11\pi }}{2}$

angeordnet ist. Das Maximum des zweiten Teilsegments 2.2 eines oder jedes Paars im äußeren Kreis 12 ist mit dem Maximum des ersten Teilsegments 2.1 des jeweils nachfolgenden Paars im äußeren Kreis 12 durch ein in Rotationsrichtung d verlaufendes Leiterbahnsegment 6 verbunden.Each of the sub-segments 2.1, 2.2 or 3.1, 3.2 is designed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum (i.e. $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

until $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

for the sine function and π to 2π for the cosine function). For the sine function, a plurality of pairs of sub-segments 2.1, 2.2 are arranged periodically along a direction of rotation d of the encoder 10 with a distance of, for example, 4π, based on a period of this sine function, in an outer circle 12 and an inner circle 13 arranged concentrically in the outer circle 12, wherein in each of the circles 12, 13 a first sub-segment 2.1 of a pair with its minimum at the angular position $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

is arranged, wherein in each of the circles 12, 13 a second sub-segment 2.2 of the pair with its minimum at the angular position $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">3\pi </figure-callout>}}{2}$

is arranged. The two first sub-segments 2.1 of the circles 12, 13 are connected in series with each other and the two second sub-segments 2.2 of the circles 12, 13 are connected in series with each other and the minima of the two sub-segments 2.1, 2.2 of the pair in the inner circle 13 are connected to each other by a conductor track segment 5 running in the direction of rotation d. The next pair formed in the same way follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair in each of the circles 12, 13, i.e. a first sub-segment 2.1 of the next pair in each of the circles 12, 13 is with its minimum in each case at the angular position $\frac{\mathrm{7\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="9\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">9\pi </figure-callout>}}{2}$

arranged, with a second sub-segment 2.2 of the next pair in each of the circles 12, 13 each having its minimum at the angular position $\frac{\mathrm{9\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the angular position $+\frac{\mathrm{<figure-callout\; id="2"\; label="11\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">11\pi </figure-callout>}}{2}$

The maximum of the second sub-segment 2.2 of one or each pair in the outer circle 12 is connected to the maximum of the first sub-segment 2.1 of the respective subsequent pair in the outer circle 12 by a conductor track segment 6 running in the direction of rotation d.

In this case, the conductor track segment 5, 6 can be arranged offset from the respective maxima or minima by a particularly small distance in a radial direction r, i.e. at right angles to the direction of rotation d.

Similarly, for the cosine function along the direction of rotation d of the encoder 10, a plurality of pairs of sub-segments 3.1, 3.2 are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, in the outer circle 12 and in the inner circle 13, wherein in each of the circles 12, 13 a first sub-segment 3.1 of a pair is arranged with its minimum at the angular position π and its maximum at the angular position 2π, wherein in each of the circles 12, 13 a second sub-segment 3.2 of the pair is arranged with its minimum at the angular position 2π and its maximum at the angular position 3π. The two first sub-segments 3.1 of the circles 12, 13 are connected in series with each other and the two second sub-segments 3.2 of the circles 12, 13 are connected in series with each other, the maxima of the two sub-segments 3.1, 3.2 of the pair in the outer circle 12 being connected to each other by a conductor track segment 7 running in the direction of rotation d. The next pair formed in the same way follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 3.1 of the next pair in each circle 12, 13 is arranged with its minimum at the angular position 5π and its maximum at the angular position 6π, wherein a second sub-segment 3.2 of the next pair in each circle 12, 13 is arranged with its minimum at the angular position 6π and its maximum at the angular position 7π. The minimum of the second sub-segment 3.2 of one or each pair in the inner circle 13 is connected to the minimum of the first sub-segment 3.1 of the respective subsequent pair in the inner circle 13 by a conductor track segment 8 running in the direction of rotation d.

In this case, the conductor track segment 7, 8 can be arranged offset in the radial direction r from the respective maxima or minima by a particularly small distance.

For the series connection of mutually assigned sub-segments 2.1, 2.2, 3.1, 3.2 in the outer and inner circles 12, 13, further conductor track segments 14 can be provided, which preferably run either in the direction of rotation d or in the radial direction r.

In this way, the sine functions and the cosine functions of the secondary coil arrangement 1 are interlocked without any crossing points occurring between the conductor tracks.

As well as from 4 As can be seen, the secondary coil arrangement 1 has no crossings, so that there is no need to use vias.

The multiple secondary coil arrangement 1 has several advantages over the simple design. Firstly, the area penetrated by the alternating field is enlarged and thus the signal swing is increased. This improves the signal-to-noise ratio and thus ensures an even more robust overall system. By shortening the period length at higher resolutions, the slope of the sub-segments 2.1, 2.2, 3.1, 3.2 increases and these can then approach a straight line. The multiple arrangement of the sub-segments 2.1, 2.2, 3.1, 3.2 prevents exactly this problem. The required slope is distributed over several sub-segments 2.1, 2.2, 3.1, 3.2 with a lower slope. Another advantage is the enlargement of the area and thus a higher signal amplitude. 5 is a schematic view of several sinusoidal sub-segments 2.1, 2.1', 2.1'', 2.1''' with different period lengths. With a shorter period length, i.e. dividing the full circle into more periods, the sub-segments 2.1, 2.1', 2.1'', 2.1''' approach a straight line.

6 is a schematic view of another embodiment of a linear inductive encoder 10 with a multiple secondary coil arrangement 1.

This embodiment uses a multiple arrangement of the sub-segments 2.1, 2.2, 3.1, 3.2 in a longitudinal position, whereby the number of arrangements must always be an even number. Every second sub-segment 2.1, 2.2, 3.1, 3.2 is arranged mirrored for a more clever connection in the transverse direction y. This eliminates the connections in the longitudinal direction x between the sub-segments 2.1, 2.2, 3.1, 3.2 in a longitudinal position, as in 3 are present. In addition, the offset in the transverse direction y can be minimized or eliminated entirely. This allows the secondary coil arrangement 1 to be made more compact and the offset of the sensor signal is reduced. 7 shows this embodiment using a tested circuit board layout.

By using sub-segments 2.1, 2.2, 3.1, 3.2 with different amplitudes, the offset in the transverse direction y can be completely avoided. A negative influence on the signal quality could not be proven in measurements.

8 is a schematic view of an analog embodiment of a rotary inductive encoder 10 with subsegments 2.1, 2.2, 3.1, 3.2 with different amplitudes without offset in the radial direction r.

The other sub-segments 2.1, 2.2, 3.1, 3.2 span an area with the same dimensions as the original. This significantly increases the area over which the modulation with the target 4 occurs. As long as the spanned area has a sinusoidal shape at its edges in the longitudinal direction x and is geometrically positioned correctly, each area contributes to increasing the signal amplitude.

The polarity of the induced voltage does not change by adding further sub-segments 2.1, 2.2, 3.1, 3.2. Whether a positive or negative voltage is added to a sub-segment 2.1, 2.2, 3.1, 3.2 The voltage induced depends on the direction of the entire loop. The term loop refers to the sub-segments 2.1, 2.2, 3.1, 3.2 and connections that span a surface.

In order for a negative voltage to be induced, the current would have to flow through the loop in the opposite direction. If this area were then electrically shifted by 180°, the polarity of the voltage would be reversed and the signal amplitude would be increased again. However, this arrangement again requires unwanted crossings and is therefore not explained further here. Such an embodiment then requires four secondary coils instead of two. This means one secondary coil each for Sin+, Sin-, Cos+, Cos-. 9 shows schematically such an arrangement.

Also in the embodiment according to 6 a meandering secondary coil arrangement 1 is provided which has a plurality of partial segments 2.1, 2.2 of a sine function designed as conductor tracks and a plurality of partial segments 3.1, 3.2 of a cosine function each with a length of 180° or π with respect to the period length of the sine function or cosine function under consideration of 2π. These partial segments 2.1, 2.2 or 3.1, 3.2 are connected to one another over two periods in such a way that no crossings occur. These partial segments 2.1, 2.2 or 3.1, 3.2 span an area which is used for modulation with a target 4. This area is penetrated by an alternating field generated by a primary coil 11. An alternating voltage is thus induced in the secondary coil arrangement 1, which is referred to as a carrier.

bis $+\frac{\mathrm{\pi }}{2}$

bei der Sinusfunktion und π bis 2π bei der Cosinusfunktion) oder von deren Maximum bis zum nachfolgenden Minimum (das heißt $+\frac{\mathrm{\pi }}{2}$

bis $+\frac{\mathrm{3\pi }}{2}$

bei der Sinusfunktion und 0 bis π bei der Cosinusfunktion) ausgebildet. Dabei sind für die Sinusfunktion entlang einer Längsrichtung x des Encoders 10 eine Mehrzahl von Paaren von Teilsegmenten 2.1, 2.2 periodisch mit einem Abstand von beispielsweise 4π, bezogen auf eine Periodendauer dieser Sinusfunktion, in einer ersten Ebene 15 und einer parallel dazu angeordneten zweiten Ebene 16 angeordnet, wobei in der ersten Ebene 15 ein erstes Teilsegment 2.1 eines Paars mit seinem Minimum bei der Position $-\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{\pi }}{2}$

angeordnet ist, wobei in der zweiten Ebene 16 ein erstes Teilsegment 2.1 eines Paars mit seinem Maximum bei der Position $-\frac{\mathrm{\pi }}{2}$

und seinem Minimum bei der Position $+\frac{\mathrm{\pi }}{2}$

angeordnet ist, wobei in der ersten Ebene 15 ein zweites Teilsegment 2.2 des Paars mit seinem Minimum bei der Position $\frac{\mathrm{\pi }}{2}$

und seinem Maximum bei der Position $+\frac{\mathrm{3\pi }}{2}$

angeordnet ist, und wobei in der zweiten Ebene 16 ein zweites Teilsegment 2.2 des Paars mit seinem Maximum bei der Position $\frac{\mathrm{\pi }}{2}$

und seinem Minimum bei der Position $+\frac{\mathrm{3\pi }}{2}$

angeordnet ist. Dabei sind die beiden ersten Teilsegmente 2.1 der Ebenen 15, 16 zueinander in Reihe geschaltet und die beiden zweiten Teilsegmente 2.2 der Ebenen 15, 16 zueinander in Reihe geschaltet und die Maxima der beiden Teilsegmente 2.1, 2.2 des Paars in der ersten Ebene 15 miteinander durch ein in Längsrichtung x verlaufendes Leiterbahnsegment 5 verbunden. Das nächste in gleicher Weise gebildete Paar folgt in einem Abstand von 2π ab dem Ende des vorherigen Paars oder 4π ab dem Beginn des vorherigen Paars in jeder der Ebenen 15, 16, das heißt ein erstes Teilsegment 2.1 des nächsten Paars in jeder der Ebenen 15, 16 ist mit seinem Minimum bzw. Maximum jeweils bei der Position $\frac{\mathrm{7\pi }}{2}$

und seinem Maximum bzw. Minimum bei der Position $+\frac{\mathrm{9\pi }}{2}$

angeordnet, wobei ein zweites Teilsegment 2.2 des nächsten Paars in jeder der Ebenen 15, 16 jeweils mit seinem Minimum bzw. Maximum bei der Position $\frac{\mathrm{9\pi }}{2}$

und seinem Maximum bzw. Minimum bei der Position $+\frac{\mathrm{11\pi }}{2}$

angeordnet ist. Das Minimum des zweiten Teilsegments 2.2 eines oder jedes Paars in der zweiten Ebene 16 ist mit dem Minimum des ersten Teilsegments 2.1 des jeweils nachfolgenden Paars in der zweiten Ebene 16 durch ein in Längsrichtung x verlaufendes Leiterbahnsegment 6 verbunden.Each of the sub-segments 2.1, 2.2 or 3.1, 3.2 is designed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum (i.e. $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

until $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

for the sine function and π to 2π for the cosine function) or from its maximum to the following minimum (that is $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

until $<figure-callout\; id="2"\; label="+\; 3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">+</figure-callout>\frac{\mathrm{3\pi }}{}\frac{\mathrm{}}{2}$

for the sine function and 0 to π for the cosine function). For the sine function, a plurality of pairs of sub-segments 2.1, 2.2 are arranged periodically along a longitudinal direction x of the encoder 10 with a distance of, for example, 4π, based on a period of this sine function, in a first plane 15 and a second plane 16 arranged parallel thereto, wherein in the first plane 15 a first sub-segment 2.1 of a pair with its minimum at the position $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

is arranged, wherein in the second plane 16 a first sub-segment 2.1 of a pair with its maximum at the position $-\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

and its minimum at position $+\frac{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">\pi </figure-callout>}}{2}$

is arranged, wherein in the first plane 15 a second sub-segment 2.2 of the pair with its minimum at the position $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">3\pi </figure-callout>}}{2}$

and wherein in the second plane 16 a second sub-segment 2.2 of the pair with its maximum at the position $\frac{\mathrm{\pi }}{}$$\frac{\mathrm{}}{2}$

and its minimum at position $+\frac{\mathrm{<figure-callout\; id="2"\; label="3\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">3\pi </figure-callout>}}{2}$

is arranged. The two first sub-segments 2.1 of the levels 15, 16 are connected in series with each other and the two second sub-segments 2.2 of the levels 15, 16 are connected in series with each other and the maxima of the two sub-segments 2.1, 2.2 of the pair in the first level 15 are connected to each other by a conductor track segment 5 running in the longitudinal direction x. The next pair formed in the same way follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair in each of the levels 15, 16, i.e. a first sub-segment 2.1 of the next pair in each of the levels 15, 16 is with its minimum or maximum in each case at the position $\frac{\mathrm{7\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum or minimum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="9\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">9\pi </figure-callout>}}{2}$

arranged, with a second sub-segment 2.2 of the next pair in each of the levels 15, 16 each with its minimum or maximum at the position $\frac{\mathrm{9\pi }}{}$$\frac{\mathrm{}}{2}$

and its maximum or minimum at the position $+\frac{\mathrm{<figure-callout\; id="2"\; label="11\pi "\; filenames="DE102023102164B4\_0055.png,DE102023102164B4\_0060.png"\; state="\{\{state\}\}">11\pi </figure-callout>}}{2}$

The minimum of the second sub-segment 2.2 of one or each pair in the second level 16 is connected to the minimum of the first sub-segment 2.1 of the respective subsequent pair in the second level 16 by a conductor track segment 6 running in the longitudinal direction x.

In this case, the conductor track segment 5, 6 can be arranged offset from the respective maxima or minima by a particularly small distance in a transverse direction y, that is to say at right angles to the longitudinal direction x.

Similarly, for the cosine function along the longitudinal direction x of the encoder 10, a plurality of pairs of sub-segments 3.1, 3.2 are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, in the first plane 15 and the second plane 16, wherein in the first plane 15 a first sub-segment 3.1 of a pair with its minimum at the position 2π and its maximum at position 3π, wherein in the first level 15 a second sub-segment 3.2 of the pair is arranged with its minimum at position 3π and its maximum at position 4π, wherein in the second level 16 a first sub-segment 3.1 of a pair is arranged with its maximum at position 2π and its minimum at position 3π, wherein in the second level 16 a second sub-segment 3.2 of the pair is arranged with its maximum at position 3π and its minimum at position 4π. The two first sub-segments 3.1 of levels 15, 16 are connected in series with one another and the two second sub-segments 3.2 of levels 15, 16 are connected in series with one another, wherein the minima of the two sub-segments 3.1, 3.2 of the pair in the second level 16 are connected to one another by a conductor track segment 7 running in the longitudinal direction x. The next pair formed in the same way follows at a distance of 2π from the end of the previous pair or 4π from the beginning of the previous pair, i.e. a first sub-segment 3.1 of the next pair in each circle 12, 13 is arranged with its minimum or maximum at position 6π and its maximum at position 7π, wherein a second sub-segment 3.2 of the next pair in each plane 15, 16 is arranged with its minimum or maximum at position 7π and its maximum or minimum at position 8π. The maximum of the second sub-segment 3.2 of one or each pair in the first plane 15 is connected to the maximum of the first sub-segment 3.1 of the respective subsequent pair in the first plane 15 by a conductor track segment 8 running in the longitudinal direction x.

In this case, the conductor track segment 7, 8 can be arranged offset in the transverse direction y from the respective maxima or minima by a particularly small distance.

For the series connection of mutually assigned sub-segments 2.1, 2.2, 3.1, 3.2 in the outer and inner circles 12, 13, further conductor track segments 14 can be provided, which preferably run either in the longitudinal direction x or in the transverse direction y.

In this way, the sine functions and the cosine functions of the secondary coil arrangement 1 are interlocked without any crossing points occurring between the conductor tracks.

As well as from 6 As can be seen, the secondary coil arrangement 1 has no crossings, so that there is no need to use vias.

LIST OF REFERENCE SYMBOLS

1

Secondary coil arrangement

2.1, 2.1', 2.1'', 2.1''', 2.2

Subsegment

3.1,3.2

Subsegment

4

Target

5

Conductor track segment

6

Conductor track segment

7

Conductor track segment

8

Conductor track segment

10

Encoders

11

Primary coil

12

Circle

13

Circle

14

Conductor track segment

15

level

16

Level

d

Rotation direction

r

Radial direction

t

Time

Wow

induced voltage

x

Longitudinal direction

y

Transverse direction

Claims (11)

Secondary coil arrangement (1) for an inductive encoder (10), wherein the secondary coil arrangement (1) has a plurality of sub-segments (2.1, 2.2) of a sine function formed as conductor tracks on a circuit board and electrically connected to one another without crossing, and a plurality of sub-segments (3.1, 3.2) of a cosine function formed as conductor tracks on the circuit board and electrically connected to one another without crossing, wherein these sub-segments (2.1, 2.2, 3.1, 3.2) reproduce the sine function or the cosine function in sections with periodic interruptions, characterized in that at least one or each of the sub-segments (2.1, 2.2, 3.1, 3.2) is formed as an at least approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum or from its maximum to the subsequent minimum. Secondary coil arrangement (1) according to Claim 1 , whereby the sub-segments (2.1, 2.2) assigned to the sine function are inserted into the interruptions of the Cosine function, and wherein the sub-segments (3.1, 3.2) assigned to the cosine function intervene in the interruptions of the sine function. Secondary coil arrangement (1) according to one of the preceding claims, wherein for the sine function along a longitudinal direction (x) or rotation direction (d) of the encoder (10) in at least one plane (15, 16) or at least one circle (12, 13) a plurality of pairs of sub-segments (2.1, 2.2) each consisting of a first sub-segment (2.1) and a second sub-segment (2.2) are arranged periodically with a distance of, for example, 4π, based on a period of this sine function, wherein the second sub-segment (2.2) of the pair is arranged with its minimum at the position of the maximum of the first sub-segment (2.1) in the longitudinal direction (x) or rotation direction (d) or with its maximum at the position of the minimum of the first sub-segment (2.1) in the longitudinal direction (x) or rotation direction (d), wherein the maxima or minima of the two sub-segments (2.1, 2.2) of the pair in one of the planes (15, 16) or one of the circles (12, 13) are connected to one another by a conductor track segment (5), the next pair of sub-segments (2.1, 2.2) for the sine function following at a distance of 2π, the minimum or maximum of the second sub-segment (2.2) of the or each pair in one of the planes (15, 16) or one of the circles (12, 13) being connected to the minimum or maximum of the first sub-segment (2.1) of the respective subsequent pair by a conductor track segment (6). Secondary coil arrangement (1) according to one of the preceding claims, wherein for the cosine function along a longitudinal direction (x) or rotation direction (d) of the encoder (10) in at least one plane (15, 16) or at least one circle (12, 13) a plurality of pairs of sub-segments (3.1, 3.2) each comprising a first sub-segment (3.1) and a second sub-segment (3.2) are arranged periodically with a distance of, for example, 4π, based on a period of this cosine function, wherein the second sub-segment (3.2) of the pair is arranged with its minimum at the position of the maximum of the first sub-segment (3.1) in the longitudinal direction (x) or rotation direction (d) or with its maximum at the position of the minimum of the first sub-segment (3.1) in the longitudinal direction (x) or rotation direction (d), wherein the maxima or minima of the two sub-segments (3.1, 3.2) of the pair are in one of the Levels (15, 16) or one of the circles (12, 13) are connected to one another by a conductor track segment (7), the next pair of sub-segments (3.1, 3.2) for the cosine function following at a distance of 2π, the maximum or minimum of the second sub-segment (3.2) of the or each pair in one of the levels (15, 16) or one of the circles (12, 13) being connected to the maximum or minimum of the first sub-segment (3.1) of the respective subsequent pair by a conductor track segment (8). Secondary coil arrangement (1) according to Claim 4 , wherein one or more pairs or all pairs of sub-segments (3.1, 3.2) for the cosine function overlap in their position with a pair of sub-segments (2.1, 2.2) for the sine function, wherein the overlap in particular $\frac{\mathrm{\pi }}{2}$

amounts. Secondary coil arrangement (1) according to one of the Claims 3 until 5 , wherein the conductor track segment (5, 6, 7, 8) runs in the longitudinal direction (x) or rotational direction (d). Secondary coil arrangement (1) according to one of the Claims 3 until 6 , wherein the conductor track segment (5, 6) is arranged offset by a distance in a transverse direction (y) or radial direction (r) from the respective maxima or minima. Secondary coil arrangement (1) according to one of the Claims 3 until 7 , wherein at least two planes (15, 16) parallel to one another in the longitudinal direction (x) or concentric circles (12, 13) in the direction of rotation (d) are provided, in each of which a plurality of pairs of sub-segments (2.1, 2.2, 3.1, 3.2) for the sine function and/or cosine function are arranged, wherein corresponding sub-segments (2.1, 2.2, 3.1, 3.2) in adjacent planes (15, 16) or circles (12, 13) are connected in series with one another, wherein the minima or maxima of the two sub-segments (2.1, 2.2, 3.1, 3.2) of a pair in one of the planes (15, 16) or in one of the circles (12, 13) are connected to one another by a conductor track segment (5, 7), wherein the maximum or minimum of the second sub-segment (2.2) of one or each pair in another plane (15, 16) or another circle (12, 13) is connected to the maximum or minimum of the first sub-segment (2.1) of the respective subsequent pair in the same plane (15, 16) or in the same circle (12, 13) by a conductor track segment (6, 8). Secondary coil arrangement (1) according to one of the Claims 3 until 8 , wherein in each plane (15, 16) or in each circle (12, 13) there are only partial segments (2.1, 2.2, 3.1, 3.2) formed as at least approximately S-shaped sections of a sine function or cosine function from its minimum to the following maximum, or only partial segments (2.1, 2.2, 3.1, 3.2) formed as at least approximately S-shaped sections of a sine function or cosine function from its maximum to the following minimum formed sub-segments (2.1, 2.2, 3.1, 3.2) are arranged. Secondary coil arrangement (1) according to Claim 9 , wherein at least two planes (15, 16) parallel to one another in the longitudinal direction (x) or circles (12, 13) concentric in the direction of rotation (d) are provided, wherein in at least one of the planes (15, 16) or in at least one of the circles (12, 13) only partial segments (2.1, 2.2, 3.1, 3.2) are arranged which are in the form of at least an approximately S-shaped section of a sine function or cosine function from its minimum to the subsequent maximum, wherein in at least one other of the planes (15, 16) or in at least one other of the circles (12, 13) only partial segments (2.1, 2.2, 3.1, 3.2) are arranged which are in the form of at least an approximately S-shaped section of a sine function or cosine function from its maximum to the subsequent minimum. Inductive encoder (10) comprising a primary coil (11), a secondary coil arrangement (1) according to one of the preceding claims and a target (4) movable relative to the secondary coil arrangement (1) for field weakening of an alternating magnetic field generated by the primary coil (11) when subjected to an alternating voltage at the secondary coil arrangement (1).

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