DE102015207275A1 - Measuring standard with signal-compensating markings - Google Patents

Abstract

The invention relates to a material measure (20), which is formed by a material strip (23), which consists of a ferromagnetic material, wherein the material strip (23) is elongated along a measuring direction (11), wherein along the measuring direction (11) A plurality of markings (21) are arranged on the strip of material in a row, wherein the markings (21) are respectively formed by apertures or recesses of constant depth, wherein the markings (21) each have a marking outline (50), wherein the markings (21) encode a binary random number sequence, each marker outline (50) being located entirely within an associated imaginary rectangle (60) having first, second, third and fourth rectangle sides (61; 62; 63; 64) the distance between the third rectangular sides (63) of two immediately adjacent imaginary rectangles (60) is an integer multiple of a first Te ilungsabstands is. According to the invention, the clear distance between two immediately adjacent imaginary rectangles (60) is different from an integer multiple of the first pitch.

Description

The invention relates to a material measure according to the preamble of claim 1.

From the EP 2 502 030 B1 is a material measure known, which is intended for use in a position measuring system. The position measuring system is an absolute position measuring system, wherein the marks of the material measure code a binary random number sequence. The material measure is read inductively by a scanning device. For this purpose, two types of Maßverkörperungen come into consideration, namely those that consist of a material with high electrical conductivity, such as copper (eddy current principle) and those that consist of a ferromagnetic material. The present invention is concerned with the latter type.

In inductive scanning typically differentially interconnected coil pairs are used to minimize the signal offset. In the EP 2 502 030 B1 these are arranged side by side transversely to the measuring direction, with two complementary rows of markings being used. The individual coils of a coil pair are firmly wired together. The applicant has in the not yet disclosed German patent application with the file number 10 2014 216 036.7 proposed a position measuring system comprising only individual coils, which are arranged in the measuring direction in a row. These are dynamically interconnected during operation in different ways, so that the individual coils of a differential coil pair are arranged side by side in the measuring direction. The present invention addresses a problem that occurs primarily in the latter type.

When the receiver coils are moved over a side boundary of a marker, the amplitude of the alternating voltage induced in the receiver coils does not change abruptly, but rather a steady increase or decrease of the signal amplitude takes place.

In the known position measuring systems, the markings of openings or recesses are formed in a material band. The corresponding marking outline is rectangular. The width and the clear distance of the rectangles are each an integer multiple of a first pitch. Applicant's experiments have shown that the induced AC voltage of a single receiver coil, which is exactly centered over a transverse edge portion of a marking contour oriented transversely to the measuring direction, has an amplitude greater than 50% of the maximum amplitude of the induced AC voltage. This considerably complicates the signal evaluation.

An advantage of the invention is that the evaluation of the induced in the receiver coils AC voltages for position determination is particularly simple. In particular, the amplitude of the alternating voltages induced in the receiver coils at a defined position in relation to the division grid corresponding to the first pitch is substantially equal to 50% of the maximum signal amplitude.

According to the independent claim, it is proposed that the clear distance between two immediately adjacent, imaginary rectangles is different from an integer multiple of the first pitch. This results in a shift of the signal transition with respect to the mentioned division grid. Said clear distance is preferably selected such that the amplitude of the alternating voltages induced in the receiver coils at a defined position with respect to the division grid corresponding to the first pitch is substantially 50% of the maximum signal amplitude. Said clear distance is the distance of the third and the fourth side of the rectangle of the immediately adjacent imaginary rectangles.

The material band preferably has a constant thickness, which is preferably smaller than the first pitch. The thickness is, for example, 0.3 mm, the first pitch being, for example, 1 mm. The width of the material strip is preferably greater than the first pitch, wherein it is for example 5 mm. The material band is preferably made of stainless steel. The markings may be filled with a non-ferromagnetic material, preferably being empty or filled with air. The transmitter winding arrangement and / or the receiver coils are preferably designed as planar winding arrangements. The material measure is preferably part of a guide rail of a linear roller bearing, for example, according to the EP 1 052 480 B1 is trained. If the first and the second side of the rectangle are associated with a plurality of straight portions of the marking contour, which are parallel to the measuring direction, wherein they are arranged offset transversely thereto, said rectangular sides preferably coincide with those straight portions having the greatest length in total.

In the dependent claims advantageous refinements and improvements of the invention are given.

It can be provided that the marking outlines in each case completely coincide with the associated imaginary rectangle. This is the embodiment which has the least difference compared to the known material measure, while still giving the above-mentioned advantage. This material measure is just as easy to produce as the known material measure. In this case, preferably a photochemical etching process is used.

It can be provided that the third side of the rectangle is associated with a single straight third edge portion of the relevant marking outline, wherein the fourth side of the rectangle is associated with a single straight fourth edge portion of the respective marking outline, wherein the third and the fourth edge portion are arranged parallel to each other the measuring direction include an angle different from 90 °. In the simplest case, the marking outline is designed in the form of a parallelogram. However, the marking outline may have a shape deviating from a parallelogram in the region of the first and the second side of the rectangle. This marking outline lengthens the movement path of the scanning device relative to the measuring standard, in that the continuous signal transition takes place at a marking boundary. This ensures that, in each position of the scanning device, each marking boundary of at least one receiver coil is detected in such a way that an alternating voltage is induced whose amplitude lies between the minimum and the maximum amplitude of the induced alternating voltages. This simplifies the determination of the random number sequence read by the material measure. In addition, a positional error of the scanning device with respect to the measuring standard transversely to the measuring direction has less effect than in the above-proposed rectangular shape of the marking contour.

It can be provided that the third side of the rectangle is associated with an outwardly or inwardly bent extending third edge portion of the marking outline, wherein the fourth side of the rectangle is associated with an outwardly or inwardly bent extending fourth edge portion of the marking outline. Preferably, the third and the fourth edge portion are mirror-symmetrical to each other. It is conceivable that the third and the fourth edge section run in the form of a kink-free arch. The term "bent" is intended to include but also courses of the third and fourth edge portion, which have a kink.

It can be provided that the third and the fourth edge portion each have two straight subsections which enclose an angle which is greater than 90 °. This ensures that the signal curve in the region of a marking boundary is substantially linear. The third and / or the fourth edge portion are preferably formed mirror-symmetrically with respect to a center line of the material measure. Preferably, the third and / or the fourth edge portion have exactly two straight subsections.

It can be provided that the two associated straight subsections adjoin one another in a corner or in a circle radius. The circle radius is preferably made small.

It may be provided that the edge portions of the marking outline assigned to the first and second rectangle sides are mirror-symmetrical to one another. As a result, signal errors can be avoided, especially those that are not compensated.

It can be provided that at least a fifth edge portion of the marking contour is assigned to the first side of the rectangle, which is bent relative to the measuring direction, wherein the second side of the rectangle is associated with at least a sixth edge portion of the marking contour, which is bent relative to the measuring direction. It has been found that the amplitude of the alternating voltages induced in the receiver coils in some positions of said receiver coils in the region of a marking boundary can reach a value which is above the maximum value which theoretically should only occur if the receiver coil is completely over ferromagnetic material , It may also happen that said amplitude falls below a minimum value which theoretically should only occur when the receiver coil is completely over air or a non-ferromagnetic material. This effect can be compensated by the proposed design of the marking outline. The term "bent" is intended to include but also courses of the fifth and sixth edge portion, which have a kink. The fifth and the sixth edge portion may optionally be bent inwards or outwards.

It can be provided that the fifth and / or the sixth edge portion has at least one straight subsection.

It can be provided that the fifth and / or the sixth edge portion has at least one bent portion bend-free.

It can be provided that the first edge portions of all marking outlines in Measuring direction are arranged in alignment, wherein the second edge portions of all marking outlines are arranged in the measuring direction in alignment. During operation of the position measuring system, the material measure is preferably placed under tension in such a way that the predetermined first pitch is maintained very accurately. The proposed embodiment of Markierungsrumrisse is avoided that the material measure assumes a deviating from the exact straight shape course. This would result in errors when reading the marks.

It can be provided that the distance of the third and the fourth side of the rectangle between 20% and 50% of the first pitch is greater than the nearest integer multiple of the first pitch. With this design of a marking contour, the signal profile explained above as being preferred results in the region of a marking boundary.

The measuring standard according to the invention is preferably used in a position measuring system, wherein a scanning device is provided, which has at least five receiver coils arranged in a row in the measuring direction, wherein the scanning device has a transmitter winding arrangement, which is immovable relative to the receiver coils, wherein the scanning device in Measuring direction along the measuring scale is movable, wherein the receiver coils, the transmitter coil assembly and the material measure are arranged so that the position of the material measure relative to the sensing device influences the inductive coupling between the transmitter coil assembly and the receiver coils. The distance of all pairs of adjacent receiver coils in the measuring direction is preferably equal to a constant second pitch. The second pitch is preferably equal to or less than the first pitch, for example, 0.8 mm.

It can be provided that the transmitter winding arrangement delimits a plurality of separate transmitter surfaces, which are arranged in the measuring direction in a row, wherein in a transmitter surface at most one associated receiver coil is arranged. In such a position measuring system, the problem underlying the invention occurs particularly strongly, so that the compensation according to the invention is particularly advantageous. The receiver coils are preferably arranged completely within the respective associated transmitter surface.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

The invention will be explained in more detail below with reference to the accompanying drawings. It shows:

1 a rough schematic representation of a position measuring system according to a first embodiment of the invention;

2 a rough schematic representation of a part of a material measure according to the first embodiment of the invention according to 1 ;

3 a rough schematic representation of a portion of a material measure according to a second embodiment of the invention;

4 a rough schematic representation of a part of a material measure according to a third embodiment of the invention;

5 a rough schematic representation of a part of a material measure according to a fourth embodiment of the invention;

6 a rough schematic cross section of the position measuring system according to 1 , wherein the markings are formed as openings; and

7 one of the 6 corresponding representation, wherein the markings are formed as recesses.

1 shows a rough schematic representation of a position measuring system 10 according to a first embodiment of the invention. The position measuring system 10 includes a material measure 20 and a scanning device 30 , The measuring standard 20 is as a material band 23 executed, which consists of a ferromagnetic material, for example made of stainless steel, for example, it has a constant thickness of 0.3 mm. The measuring standard 20 extends at a constant width 27 in a measuring direction 11 , Along the measuring direction 11 is on the material measure 20 a variety of markings 21 arranged in a row, which is based on a constant first pitch λ. The marks 21 can optionally as breakthroughs (No. 22 in 6 ) or as recesses (No. 22a in 7 ) be formed with a constant depth. The marks 21 may have two states, they may or may not be present. The marks 21 encode a binary random number sequence, wherein a first pitch λ corresponds to a binary digit of this code. The shape of the markings will be discussed below with reference to 2 to 5 explained. The marks 21 are designed so that no Transverse webs are required in the material band, which with the first pitch λ regularly spaced on the material band 23 are arranged. Transverse to the measuring direction 11 on both sides of the markings 21 has the metal band 23 one side bar each 24 , so that a coherent measuring standard 20 results. The marks 21 are preferably designed as a space filled with air. But they can also be filled with a material which is not ferromagnetic, for example with brass.

The scanning device 30 is in measuring direction 11 movable relative to the material measure 20 , Preferably, the material measure 20 attached to the guide rail of a linear roller bearing, wherein the scanning device 30 is attached to the associated carriage. A corresponding linear roller bearing is from the DE 10 2007 042 796 A1 known. The scanning device 30 includes an evaluation module 34 , which is preferably in the form of a separate electronic board. The remainder of the scanner 30 , in particular the transmitter winding arrangement 41 , the receiver coils 40 , the switching device 70 and the operational amplifier 80 are in close spatial proximity to the material measure 20 arranged while the evaluation module 34 In contrast, a greater spatial distance to the material measure 20 can have.

The transmitter coil arrangement 41 and the receiver coils 40 are each formed as a planar winding arrangements. In 1 in each case only one winding circulation is shown, wherein both the transmitter winding arrangement 41 as well as the receiver coils 40 actually each have a plurality of substantially parallel Windungsumläufen. In 1 is both in the transmitter coil arrangement 41 as well as in the material measure 20 a midline 25 located. These two centerlines 25 lie, contrary to the illustration in 1 , congruent to each other, wherein the transmitter winding arrangement 41 and the receiver coils 40 at a short distance to the material measure 20 are arranged (see. 6 and 7 ). This influences the material measure 20 the inductive coupling between the transmitter winding arrangement 41 and the receiver coils 40 , Ie one in the transmitter coil arrangement 41 fed AC induced in the receiver coils 40 an alternating voltage whose amplitude depends on the position of the scanning device 30 opposite the measuring standard 20 depends.

The transmitter coil arrangement 41 In the present case, it is designed as a meander structure, wherein it has a plurality of separate transmitter surfaces 42 bounded, which in measuring direction 11 arranged in a row. The transmitter coil arrangement 41 includes a first and second group 44 ; 45 of serpentine formed tracks 43 which extend along the measuring direction 11 cross several times. At the with the no. 46 marked point are the said tracks 43 connected together in such a way that the transmitter winding arrangement 41 is formed by a single continuous conductor. The transmitter coil arrangement 41 may alternatively be composed of a plurality of individual coils, each having a single associated transmitter surface 42 they are optionally connected in series or in parallel. If the transmitter coil arrangement 41 from the AC power source 31 is fed with an alternating current, results in all transmitter areas 42 a magnitude substantially the same electromagnetic alternating field, the field direction in immediately adjacent transmitter surfaces 42 is opposite. The AC power source 31 is preferably part of the evaluation module 34 ,

In the transmitter areas 42 is in each case a single receiver coil 40 completely arranged. In close proximity to the receiver coils 40 is the operational amplifier 80 arranged, which is preferably formed fully different. Two adjacent receiver coils 40 pointing in the direction of measurement 11 each have a constant second pitch δ, which is for example 0.8 mm. The wiring of the operational amplifier 80 is in 1 shown in simplified form, with only the two for the fully differential operational amplifier 80 identifying feedback resistors 85 ; 86 are shown. The first feedback resistor 85 connects the first input port 81 of the operational amplifier 80 with the first output terminal 83 of the operational amplifier 80 , The second feedback resistor 86 connects the second input terminal 82 of the operational amplifier 80 with the second output terminal 84 of the operational amplifier 80 ,

The first and second output ports 83 ; 84 are input side to an analog-to-digital converter 32 connected, so the analog-to-digital converter 32 can measure the corresponding electrical measurement voltage M. The corresponding digital value is sent to a programmable digital computer 33 passed. The programmable digital computer 33 and the analog-to-digital converter 32 are preferably part of the evaluation module 34 , wherein they are most preferably designed in the form of a microcontroller.

The first and the second input connection point 81 ; 82 are via a switching device 70 with the different receiver coils 40 connected. The switching device 70 includes a first signal line 75 which are connected to the first input connection point 81 of the operational amplifier 80 connected. Next is a second signal line 76 to the second input terminal 82 of the operational amplifier 80 connected. One connection each receiver coil 40 is to a third signal line 77 connected. The other connection of a receiver coil 40 is via an associated switching means 71 ; 72 either with the first or the second signal line 75 ; 76 connected. Preferably, each switching means 71 ; 72 ; 73 ; 74 a first state in which it has a first electrical resistance, wherein it has a second state in which it has a second electrical resistance, wherein the second electrical resistance is at least 1000 times greater than the first electrical resistance, wherein the at least a switching means between the first and the second state is switchable. In the present application it is assumed that a receiver coil 40 in the second state of the associated switching means 71 ; 72 not to the operational amplifier 80 connected. Preferably, the switching means 71 ; 72 ; 73 ; 74 used on the basis of semiconductors. Thus, for example, a first electrical resistance of 0.9 Ω can be achieved, wherein a second electrical resistance can be achieved, which results in a signal attenuation of at least 60 dB. A corresponding switching means is the subject of the data sheet, which on 19.03.2015 under the Internet address http://www.ti.com/lit/ds/symlink/ts5a623157.pdf was available.

In 1 are exemplary seven receiver coils 40 represented, each with an index n, along the measuring direction 11 counts. It is understood that the position measuring system 10 much more, for example thirty, receiver coils 40 can have. The receiver coils 40 with the indices n = 1, 3, 5, 7 are each via a first switching means 71 with the first signal line 75 connected. The receiver coils arranged in between 40 with the indices n = 2, 4, 6 each have a second switching means 72 with the second signal line 76 connected. The interconnection described above results in the two selected receiver coils being differentially interconnected, with the input side being connected to the operational amplifier 80 are connected. Accordingly, external interference fields affect both receiver coils 40 acting in the same way, not on the measurement voltage M from. For the proper differential interconnection of two receiver coils, it depends on the winding direction of the respective receiver coils and on which connection with the third signal line 77 connected to.

With the fourth switching means 74 becomes the third signal line 77 with the first input terminal 81 the operational amplifier 80 connected. This is just a single receiver coil 40 on the input side to the operational amplifier 80 connected, which via a second switching means 72 with the second signal line 76 connected is. If a single receiver coil 40 to be used, which has a first switching means 71 with the first signal line 75 Incidentally, the third switching means alone is connected 73 closed. With the third switching means 73 becomes the third signal line 77 with the second input terminal 82 of the operational amplifier 80 connected.

The first to fourth switching means 71 ; 72 ; 73 ; 74 are preferably from the programmable digital computer 33 controlled, with the corresponding control lines in 1 are not shown.

2 shows a rough schematic representation of a part of a material measure 20 according to the first embodiment of the invention according to 1 , Below the material measure 20 a diagram is shown in which a stress ratio k is plotted against a position x. The position x is the position of a single receiver coil (No. 40 in 1 ) relative to the material measure 20 , The voltage ratio k indicates the amplitude of the alternating voltage induced in the receiver coil under consideration. The value 100% occurs when the receiver coil is completely over ferromagnetic material. When the receiver coil is completely over a marker 21 is the voltage ratio is approximately 0%, because the inductive coupling between the transmitter coil assembly and the receiver coil is very weak due to the lack of ferromagnetic material.

In the first embodiment, the marker outline is 50 rectangular, so that the imaginary rectangle 60 according to the independent claim completely with the marking outline 50 coincides. The imaginary rectangle 60 has a first, a second, a third and a fourth rectangle side 61 ; 62 ; 63 ; 64 , The first and the second rectangle side 61 ; 62 run parallel to the measuring direction 11 , where the third and the fourth rectangle side 63 ; 64 perpendicular to the measuring direction 11 run. The distance 65 the first and the second rectangle side 61 ; 62 corresponds to the width of the marking 21 , This is made slightly smaller than the width 27 of the material band 23 so that the two opposite side bars 24 stay standing, which the material band 23 hold together in one piece. The distance 66 the third and the fourth rectangle side 63 ; 64 is the length of the mark 21 , In the present case, this is slightly larger than an integer multiple of the first pitch. How out 1 can be seen, the first pitch λ can be determined by, for example, the distances of the third sides of the rectangle 63 all marks 21 measures, wherein the shortest of these distances is equal to twice the first pitch λ.

The distance 66 or the clear distance (no. 67 in 1 ) of two immediately adjacent imaginary rectangles 60 is chosen so that the path distance 13 the 50% values 12 of the voltage ratio k is as exactly as possible an integer multiple of the first pitch λ. For example, if the first pitch λ is 1.0 mm, the distance 66 for example, be 1.4 mm, wherein the clear distance (no. 67 in 1 ) is, for example, 0.6 mm.

3 shows a rough schematic representation of a part of a material measure 20 according to a second embodiment of the invention. The marking outline 50 is designed in the form of a parallelogram, so that he no longer completely with the imaginary rectangle 60 coincides. The imaginary rectangle 60 is in 3 drawn with dashed lines. The only straight first edge section 51 the marking outline 50 is completely on the first rectangle side 61 located, with the first rectangle side 61 longer than the first edge section 51 is. The only straight second edge section 52 the marking outline 50 is completely on the second rectangle side 62 located, with the second rectangle side 62 longer than the second edge section 52 is.

The third rectangle side 63 is a single straight third edge section 53 of the marking in question 50 completely assigned within the imaginary rectangle 60 is arranged. The fourth rectangle side 64 is a single straight fourth edge section 54 of the marking in question 50 completely assigned within the imaginary rectangle 60 is arranged. The third and the fourth edge section 53 ; 54 are arranged parallel to each other, with the measuring direction 11 include an angle different from 90 °.

The point 68 at which the third rectangle side 63 with the marking outline 50 coincides, is the corner between the third and the second edge portion 53 ; 52 , The point 69 on which the fourth rectangle side 64 with the marking outline 50 coincides, is the corner between the fourth and the first edge portion 54 ; 51 ,

Like a comparison of 2 and 3 results, the course of the stress ratio k over the position x in the range of 50% values 12 significantly less steep in the second embodiment than in the first embodiment. The distance 66 or the clear width (No. 67 in 1 ) is again chosen so that the distance 13 the 50% values 12 of the voltage ratio k is as exactly as possible an integer multiple of the first pitch λ.

4 shows a rough schematic representation of a part of a material measure 20 according to a third embodiment of the invention. The imaginary rectangle 60 is in 4 drawn with dashed lines. The only straight first edge section 51 the marking outline 50 is completely on the first rectangle side 61 located, with the first rectangle side 61 longer than the first edge section 51 is. The only straight second edge section 52 the marking outline 50 is completely on the second rectangle side 62 located, with the second rectangle side 62 longer than the second edge section 52 is.

The third rectangle side 63 is an outwardly extending third edge portion 53a the marking outline 50 assigned. The fourth rectangle side 64 is an outwardly extending fourth edge portion 54a the marking outline 50 assigned. The third and the fourth edge section 53a ; 54a are mirror-symmetrical to each other. The third and the fourth edge section 53a ; 54a each have exactly two straight subsections 57 which include an angle greater than 90 °. The two associated straight subsections 57 borders in a corner 58 to each other. The corners 58 form the points 68 ; 69 , where the third or the fourth rectangle side 63 ; 64 with the marking outline 50 coincides.

The course of the stress ratio k over the position x in the range of the 50% values 12 is substantially the same as the second embodiment in the third embodiment 3 , The distance 66 or the clear width (No. 67 in 1 ) is again chosen so that the distance 13 the 50% values 12 of the voltage ratio k is as exactly as possible an integer multiple of the first pitch λ.

The marking outline 50 according to the third embodiment is a total of mirror symmetry with respect to the center line 25 the measuring standard 20 educated. This causes errors in the sampling of the material measure 20 avoided.

5 shows a rough schematic representation of a part of a material measure 20 according to a fourth embodiment of the invention. This embodiment relates to several further deviations of the actual signal form from the ideal signal form for the signal evaluation. The fourth embodiment according to 5 is a modification of the first embodiment according to 2 However, it can also with the second or third embodiment according to the 3 respectively. 4 be combined.

In 5 below, the waveform is drawn with a dashed line, which can result if only the first embodiment according to 2 is used. With a solid line, the waveform is drawn, which results after the compensation measures explained below, and which is particularly suitable for a simple signal evaluation. There are three types of deviations between these waveforms 14a ; 14b ; 15a ; 15b ; 16 , which will be discussed in detail below.

The plateau effect 16 is to be observed when the considered individual coil is far away from a marking 21 completely over the ferromagnetic material of the material strip 23 located. The signal amplitude can then be slightly higher than when the single coil is at a small distance to a mark 21 completely over the ferromagnetic material of the material band 23 located. This plateau effect 16 can by auxiliary markings 21a which are opposite to the information-bearing markings 21 are very narrow. The auxiliary markings 21a are located right where there are no auxiliary markings 21a a plateau effect 16 shows. The width of the auxiliary markings 21a is just chosen so big that the plateau effect 16 disappears.

The overshoots 14a ; 14b can be observed when the considered individual coil shortly before or shortly after a mark boundary 53 ; 54 over the ferromagnetic material of the material band 23 stands. The overshooters 14a ; 14b can be counteracted by placing in the appropriate area of the material band 23 ferromagnetic material is removed. This is on the first rectangle side 61 the auxiliary marker 21a a fifth edge section 55 the marking outline 50 provided, which with respect to the measuring direction 11 bent to the outside, the second side of the rectangle 62 at least a sixth edge portion 56 the marking outline 50 the auxiliary marker 21a is assigned, which with respect to the measuring direction 11 bent outward runs.

The undershooters 15a ; 15b can be observed if the considered individual coil shortly after or just before a marking line 53 ; 54 above the clearance of a marker 21 stands. The Unterschwingern 15a ; 15b can be counteracted by placing in the appropriate area of the material band 23 ferromagnetic material is added. This is on the first rectangle side 61 the mark 21 a fifth edge section 55 the marking outline 50 provided, which with respect to the measuring direction 11 curved inward, with the second rectangle side 62 the mark 21 at least a sixth edge portion 56 the marking outline 50 is assigned, which with respect to the measuring direction 11 curved inward runs.

The fifth and / or the sixth edge section 55 ; 56 can have at least one straight subsection 57a exhibit, as in 5 at the overshoot 14b and the undershooter 15b is shown. The fifth and / or the sixth edge section 55 ; 56 can have a kink-free bent subsection 57b has, as in 5 at the overshoot 14a and the undershooter 15a is shown.

6 shows a rough schematic cross section of the position measuring system 10 to 1 , where the marks 21 as breakthroughs 22 are formed. Accordingly, the markings prevail 21 the entire thickness 26 the measuring standard 20 , The marking outline 50 is about the entire thickness 26 of the material band 23 essentially constant. Deviations can arise due to tolerances due to the preferred production with a photochemical etching process. The breakthroughs 22 are preferably from two opposite sides simultaneously from the material band 23 etched out, so that the etching time is short.

Next is in 6 the arrangement of the receiver coils 40 and the transmitter coil assembly 41 opposite the measuring standard 20 to recognize. The receiver coils 40 and the transmitter coil assembly 41 are each formed as a planar winding arrangements, which are preferably produced by means of a photochemical etching process. In 6 is in each case only a single layer for the receiver coils 40 and the transmitter coil assembly 41 provided, wherein more layers may be provided to make the number of turns as large as possible. The individual layers are each covered by an insulating layer 47 separated from each other, which may for example consist of polyimide. This plastic is electrically non-conductive, withstanding high temperatures. As far as the receiver coils 40 and / or the transmitter winding arrangement 41 Each having a plurality of layers, these are preferably electrically interconnected via vias, wherein the vias enforce one or more associated insulating layers.

The sensor distance 17 between the material measure 20 and the assembly containing the receiver coils 40 and the transmitter coil assembly 41 is preferably made small, most preferably smaller than the first pitch λ.

7 shows one of the 6 corresponding representation, with the markings 21 when recesses 22a are formed. The recesses 22a have a constant depth 22b which, for example, equal to half the thickness 26 of the material band 23 is. The recesses 22a are preferably prepared by a photochemical etching process, wherein the etching is only from one side of the material band 23 done here. Because the etch depth and therefore the depth 22b the recesses 22a is difficult to control, the breakthroughs are in accordance with 6 prefers.

Incidentally, the comments on 6 referenced, in 6 and 7 the same or corresponding parts are provided with the same reference numerals.

LIST OF REFERENCE NUMBERS

λ

first pitch

δ

second pitch

M

measuring voltage

k

tension

x

Position of a single receiver coil relative to the material measure

10

Position measuring system

11

measuring direction

12

50% value of the stress ratio

13

Distance between the 50% values of the stress ratio

14a

overshoots

14b

overshoots

15a

undershoot

15b

undershoot

16

plateau effect

17

sensor distance

20

Measuring standard

21

mark

21a

marking aid

22

breakthrough

22a

recess

22b

Depth of the recess

23

Bracelet material

24

side web

25

center line

26

Thickness of the tape measure

27

Width of the tape measure

30

scanning

31

AC power source

32

Analog to digital converter

33

programmable digital computer

34

evaluation module

40

receiver coil

41

Send Erwin extension arrangement

42

station area

43

serpentine trace

44

first group

45

second group

46

Border between the two groups of serpentine traces

47

insulating

50

mark outline

51

first edge section

52

second edge section

53

third edge section

53a

third edge section

54

fourth edge section

54a

fourth edge section

55

fifth edge section

56

sixth edge section

57

straight subsection

57a

straight subsection

57b

kink-free bent subsection

58

corner

60

imaginary rectangle

61

first rectangle side

62

second rectangle side

63

third rectangle side

64

fourth rectangle side

65

Distance between first and second rectangle side

66

Distance between third and fourth rectangle side

67

clear distance between two adjacent rectangles

68

Point at which the third rectangle side coincides with the marking outline

69

Point at which the fourth rectangle side coincides with the marking outline

70

switching device

71

first switching means

72

second switching means

73

third switching means

74

fourth switching means

75

first signal line

76

second signal line

77

third signal line

80

operational amplifiers

81

first input terminal of the operational amplifier

82

second input terminal of the operational amplifier

83

first output terminal of the operational amplifier

84

second output terminal of the operational amplifier

85

first feedback resistor

86

second feedback resistor

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2502030 B1 [0002, 0003]
• DE 102014216036 [0003]
• EP 1052480 B1 [0008]
• DE 102007042796 A1 [0033]

Cited non-patent literature

• http://www.ti.com/lit/ds/symlink/ts5a623157.pdf [0038]

Claims (14)

Measuring standard ( 20 ) for use in a position measuring system ( 10 ), wherein the material measure ( 20 ) of a material strip ( 23 ), which consists of a ferromagnetic material, wherein the material band ( 23 ) along a measuring direction ( 11 ) is elongated, wherein along the measuring direction ( 11 ) a variety of markers ( 21 ; 21a ) are arranged on the strip of material in a row, wherein the markings ( 21 ) each of breakthroughs ( 22 ) or recesses ( 22a ) are formed with constant depth, the markings ( 21 ) each have a marking outline ( 50 ), wherein at least a part of the markings ( 21 ) encodes a binary random number sequence, each marker contour ( 50 ) completely within an associated imaginary rectangle ( 60 ) with a first, a second, a third and a fourth rectangle side ( 61 ; 62 ; 63 ; 64 ), wherein the first and the second side of the rectangle ( 61 ; 62 ) parallel to the measuring direction ( 11 ), the marker outlines ( 50 ) at least one straight first edge portion ( 51 ), which with an associated first rectangle side ( 61 ), the marker outlines ( 50 ) each have at least one straight second edge portion ( 52 ) associated with an associated second rectangle side ( 62 ), wherein the third and the fourth rectangle side ( 63 ; 64 ) in each case at least at one point ( 68 ; 69 ) with the associated marking outline ( 50 ), wherein the distance of the third rectangle sides ( 63 ) of two immediately adjacent imaginary rectangles ( 60 ) is an integer multiple of a first pitch (λ), characterized in that the clear distance ( 67 ) of two immediately adjacent, imaginary rectangles ( 60 ) is different from an integer multiple of the first pitch (λ). A measuring scale according to claim 1, wherein the marking outlines ( 50 ) in each case completely with the associated imaginary rectangle ( 60 ) coincide. A measuring scale according to claim 1, wherein the third rectangle side ( 63 ) a single straight third edge portion ( 53 ) of the relevant marking outline ( 50 ), the fourth rectangle side ( 64 ) a single straight fourth edge portion ( 64 ) of the relevant marking outline ( 50 ), wherein the third and the fourth edge section ( 53 ; 54 ) are arranged parallel to one another, whereby they are aligned with the measuring direction ( 11 ) include an angle other than 90 °. A measuring scale according to claim 1, wherein the third rectangle side ( 63 ) an outwardly or inwardly bent extending third edge portion ( 53a ) of the marking outline ( 50 ), the fourth rectangle side ( 64 ) a curved outwardly or inwardly extending fourth edge portion ( 54a ) of the marking outline ( 50 ) assigned. A measuring scale according to claim 4, wherein the third and fourth edge portions ( 53a ; 54a ) two straight subsections each ( 57 ), which enclose an angle greater than 90 °. Measurement standard according to claim 5, wherein the two associated straight subsections ( 57 ) in a corner ( 58 ) or in a circle radius adjoin. Measurement standard according to one of the preceding claims, wherein the first and the second side of the rectangle ( 61 ; 62 ) associated edge portions of the marking outline ( 50 ) are mirror-symmetrical to each other. Measurement standard according to one of the preceding claims, wherein the first side of the rectangle ( 61 ) at least a fifth edge portion ( 55 ) of the marking outline ( 50 ), which with respect to the measuring direction ( 11 ) is bent, wherein the second side of the rectangle ( 62 ) at least a sixth edge portion ( 56 ) of the marking outline ( 50 ), which with respect to the measuring direction ( 11 ) is bent. Measurement standard according to claim 8, wherein the fifth and / or the sixth edge portion ( 55 ; 56 ) at least one straight subsection ( 57a ) having. Measuring standard according to claim 8 or 9, wherein the fifth and / or the sixth edge portion ( 55 ; 56 ) at least one kink-free bent subsection ( 57b ) having. Measurement standard according to one of the preceding claims, wherein the first edge sections ( 51 ) of all marking outlines ( 50 ) in the measuring direction ( 11 ) are arranged in an alignment, wherein the second edge sections ( 52 ) of all marking outlines ( 50 ) in the measuring direction ( 11 ) are arranged in a flight. Measuring standard according to one of the preceding claims, wherein the distance ( 66 ) of the third and the fourth rectangle side ( 63 ; 64 ) between 20% and 50% of the first pitch (λ) is greater than the nearest integer multiple of the first pitch (λ). Position measuring system ( 10 ) with a material measure ( 20 ) according to one of the preceding Claims, wherein a scanning device ( 30 ) is provided, the at least five receiver coils ( 40 ), which in the measuring direction ( 11 ) are arranged in a row, wherein the scanning device ( 30 ) a transmitter coil arrangement ( 41 ) immovable relative to the receiver coils (FIG. 40 ), wherein the scanning device ( 30 ) in the measuring direction ( 11 ) along the material measure ( 20 ) is movable, wherein the receiver coils ( 40 ), the transmitter coil arrangement ( 41 ) and the material measure ( 20 ) are arranged so that the position of the material measure ( 20 ) relative to the scanning device ( 30 ) the inductive coupling between the transmitter winding arrangement ( 41 ) and the receiver coils ( 40 ). Measurement standard according to one of the preceding claims, wherein the transmitter coil arrangement ( 41 ) several separate transmitter surfaces ( 42 ), which in the measuring direction ( 11 ) are arranged in a row, wherein in a transmitter area ( 42 ) at most one associated receiver coil ( 40 ) is arranged.

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