JP2016206198A - Standard comprising signal compensation mark - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a standard of a position measurement system which facilitates especially, evaluation of AC voltage which is guided by a reception coil.SOLUTION: A standard 20 is formed of a material tape 23 formed of a ferromagnetic material. The material tape 23 is extended along a measurement direction, plural marks 21 are arranged in one row on the material tape 23 along the measurement direction, in which the respective marks 21 are formed of a penetration part or a recess part having a constant depth, the marks 21 comprise a mark contour 50 respectively. At least parts of the marks 21 encode a binary random number sequence. The respective mark contours 50 correspond to inside of a corresponding virtual rectangle 60. The virtual rectangle 60 comprises first, second, third, and fourth rectangular sides (61, 62, 63, 64), and an interval of the third rectangular sides 63 of adjacent two virtual rectangles 60, is integral multiplication of an interval of first division interval. An inner size interval of adjacent two virtual rectangles 60 is different from the integral multiplication of the first division interval.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a standard device described in the superordinate concept of claim 1.

  From EP 2502030, a standard is known which is provided for use in a position measuring system. This position measurement system is an absolute position measurement system, and a binary random number sequence is encoded by a standard mark. This standard is read out inductively by the scanning device. For this purpose, two types of standard devices are targeted: a standard device composed of a material with high conductivity, for example copper (the eddy current principle), and a standard device composed of a ferromagnetic material. Become. The present invention deals with the latter type.

  Inductive scanning typically uses differentially connected coil pairs to minimize signal offset. In EP2502030, the coil pairs are arranged side by side with respect to the measuring direction, in which two complementary rows of a plurality of marks are used. The individual coils of the coil pair are fixedly wired to each other. In the unpublished German patent application 10201414216036.7, the applicant proposes a position measurement that includes only a plurality of individual coils arranged in a line in the measurement direction. Since these individual coils are dynamically interconnected in various ways during operation, the individual coils of the differential coil pair are arranged side by side in the measurement direction. The present invention deals exclusively with the problems that arise in the last type mentioned.

  When a plurality of receiving coils move on the lateral boundary of one mark, the AC voltage induced in these receiving coils does not change dramatically, but rather a monotonous increase or decrease in signal amplitude occurs.

  In the known position measuring device, the mark is formed in a penetrating portion or a concave portion of the material tape. The corresponding mark outline is formed in a rectangle. The width of the rectangle and the interval of the inner method are each an integral multiple of the first division interval. Applicants' multiple experiments have shown that the alternating voltage induced in the individual receiver coil, which is transverse to the measurement direction and exactly on the center of the outer periphery of the mark contour, is And having an amplitude that is greater than 50% of the maximum amplitude of the AC voltage being applied. This makes signal evaluation extremely difficult.

European Patent No. 2502030 German Patent Application No. 102014216036.7

  An advantage of the present invention is that it is particularly easy to evaluate the AC voltage induced in the receiving coil for determining the position. In particular, the amplitude of the AC voltage induced in the receiving coil is substantially 50% of the maximum signal amplitude at a predetermined location with reference to the division grid corresponding to the first division interval.

  It is proposed by the independent claim that the internal spacing of two adjacent virtual rectangles is different from an integral multiple of the first division interval. Thereby, signal transmission is shifted with respect to the divided grid. The internal interval is selected so that the AC voltage induced in the receiving coil is substantially 50% of the maximum amplitude at a predetermined location with reference to the division grid corresponding to the first division interval. The internal spacing is the distance between the third side of the adjacent virtual rectangle (hereinafter, this virtual rectangular side is referred to as the rectangular side) and the fourth rectangular side.

  The material tape preferably has a constant thickness which is smaller than the first division interval. This thickness is, for example, 0.3 mm, and the first division interval is, for example, 1 mm. The width of the material tape is advantageously larger than the first division interval, for example 5 mm. The material tape is preferably made of stainless steel. The mark can be filled with a non-ferromagnetic material, which is preferably empty or filled with air. The transmission winding device and / or the reception coil are advantageously formed as a flat coil device. The standard is preferably a component part of a guide rail of a linear roller bearing, for example formed according to EP 1 052 480 B1. When the first rectangular side or the second rectangular side is associated with a plurality of straight line portions of the mark outline extending in parallel with the measurement direction, and these straight line portions are shifted and arranged, The rectangular sides thus advantageously overlap the straight portions having the maximum total length.

  The dependent claims show advantageous developments and improvements of the invention.

  Each of the mark contours can completely overlap the corresponding virtual rectangle. This embodiment has only minimal differences from the known standard, but is an embodiment that provides the advantages listed above. This standard can be easily manufactured in the same manner as a known standard. Here, a photochemical etching method is preferably used.

  In the present invention, the third rectangular side is associated with the linear third outer peripheral portion of the related mark contour, the fourth rectangular side is associated with the linear fourth outer peripheral portion of the related mark contour, The third and fourth outer peripheral portions are arranged in parallel with each other, and they have an angle different from 90 ° as the measurement direction. In the simplest case, the mark outline is formed in a parallelogram shape. However, the mark contour may have a shape different from the parallelogram in the regions of the first and second rectangular sides. Such a mark contour extends the movement path of the scanning device relative to the standard, where this path is extended by the continuous transmission of signals at the mark boundary. This ensures that at each position of the scanning device, each mark boundary is detected by at least one receiving coil and an alternating voltage having an amplitude between the minimum and maximum amplitudes of the induced alternating voltage is induced. The Thereby, the random number sequence read by the standard device is easily obtained. Furthermore, the position error of the scanning device relative to the standard, transverse to the measurement direction, has no greater effect than in the case of the rectangular shape of the mark contour proposed above.

  In the present invention, the third outer peripheral portion of the mark outline, which is bent and extended outward or inward, is associated with the third rectangular side, and the fourth rectangular side is bent or extended outward or inward. It is possible to associate the fourth outer peripheral portion of the mark contour. These third and fourth rectangular sides are preferably formed mirror-symmetrically with respect to each other. It is also conceivable that the third rectangular side and the fourth rectangular side pass in the shape of a curved portion that is not bent. However, the “curved” herein includes the progress of the third rectangular side and the fourth rectangular side having a bent portion.

  In the present invention, the third rectangular side and the fourth rectangular side may each have two linear lower portions, where these lower portions make an angle greater than 90 °. This achieves that the signal course is almost linear in the region of the mark boundary. The third rectangular side and / or the fourth rectangular side are preferably formed mirror-symmetrically with respect to the center line of the standard. The third rectangular side and / or the fourth rectangular side advantageously has exactly two straight sub-parts.

  In the present invention, it is possible for two linear sub-portions associated with each other to touch each other at a corner or with a predetermined radius. This radius is advantageously configured small.

  In the present invention, it is possible to form the outer peripheral portion of the mark outline associated with the first rectangular side and the second rectangular side so as to be mirror-symmetric with each other. Thereby, in particular, signal errors that cannot be compensated can be avoided.

  In the present invention, the first rectangular side is associated with at least one fifth outer peripheral portion of the mark outline that is bent with respect to the measurement direction, and the second rectangular side is bent with respect to the measurement direction. And extending at least one sixth outer peripheral portion of the mark contour. In this embodiment, it is shown that the amplitude of the alternating voltage induced in the receiver coil is such that at several points of the receiver coil in the region of the mark boundary, the receiver coil is theoretically made of a completely ferromagnetic material. It can take a value above the maximum that should only occur if it is above. Here, it is also possible that the above amplitude drops below a minimum value that would theoretically only occur if the receiving coil is entirely on air or non-ferromagnetic material. Such an effect can be compensated by configuring the mark contour as proposed in the present invention. However, “curved” includes the progress of the fifth to sixth outer peripheral components having the bent portions. The fifth outer peripheral component or the sixth outer peripheral portion can be selectively bent inward or outward.

  In the present invention, the fifth outer peripheral portion and / or the sixth outer peripheral portion can have at least one linear sub-portion.

  In the present invention, the fifth outer peripheral portion and / or the sixth outer peripheral portion can have at least one linear lower portion curved without bending.

  In the present invention, the plurality of first outer peripheral portions of all the mark contours are arranged in a line in the measurement direction, and the plurality of second outer peripheral portions of all the mark contours are arranged in a row in the measurement direction. Is possible. During operation of the position measuring system, a tensile stress is advantageously applied to the standard so that the preset first division interval is maintained very accurately. By configuring the mark contour as proposed here, it is avoided that the standard takes a different course from a shape that is exactly linear. This avoids an error occurring when reading the mark.

  In the present invention, the interval between the third rectangular side and the fourth rectangular side is made larger than the nearest integral multiple of the first division interval by an amount between 20% and 50% of the first division interval. Is possible. By constructing the mark contour in this way, the signal course described above as advantageous occurs in the region of the mark boundary.

  The standard according to the invention is advantageously used in a position measuring system, in which a scanning device is provided having at least five receiving coils arranged in a line in the measuring direction, the scanning device comprising a receiving coil The scanning winding device is movable in the measuring direction along the standard, and the receiving coil, the transmission winding device and the standard are the scanning device. The inductive coupling between the transmission winding device and the reception coil varies depending on the position of the standard device with respect to. The spacing between all pairs adjacent in the measurement direction is advantageously equal to a constant second division spacing. This second division interval is advantageously less than or equal to the first division interval, and this second division interval is for example 0.8 mm.

  In the present invention, the transmission winding device surrounds a plurality of unique transmission surfaces arranged in a line in the measurement direction so that a maximum of one corresponding reception coil is arranged in one transmission surface. It is possible. In such a position measuring device, the problems according to the invention are particularly strong, so that the compensation according to the invention is particularly advantageous. The receiving coils are preferably arranged completely in their respective transmitting planes.

  It is obvious that the characteristic configurations listed above and those further described below can be used not only in the combinations shown, but also in other combinations or alone, without departing from the scope of the invention. It is.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic view of a position measuring device according to a first embodiment of the present invention. It is the schematic which shows a part of standard device by 1st Embodiment of this invention shown in FIG. It is a schematic diagram of a part of a standard device according to a second embodiment of the present invention. FIG. 6 is a schematic view of a part of a standard device according to a third embodiment of the present invention. FIG. 6 is a schematic view of a part of a standard device according to a fourth embodiment of the present invention. It is a schematic sectional drawing of the position measuring apparatus shown in FIG. 1 in which the mark is formed as a penetration part. FIG. 7 is a view corresponding to FIG. 6 in which the mark is formed as a recess.

  FIG. 1 shows a schematic diagram of a position measuring apparatus 10 according to a first embodiment of the present invention. The position measuring device 10 includes a standard device 20 and a scanning device 30. The standard 20 is implemented as a material tape 23, which is composed of a ferromagnetic material, for example stainless steel, and has a constant thickness of, for example, 0.3 mm. The standard 20 extends in the measurement direction 11 with a constant width 27. A plurality of marks 21 are arranged in a line along the measurement direction 11 on the standard device 20, and a fixed first division interval λ is the base of these marks. The mark 21 can be selectively formed as a through-hole (22 in FIG. 6) or a recess having a certain depth (22a in FIG. 7). The mark 21 can have two states where a mark is present or absent. A binary random number sequence is encoded by the mark 21, and the first division interval λ corresponds to the binary number of this code. The shape of these marks will be further described later with reference to FIGS. The marks 21 are configured so that a horizontal stripe is not necessary on the material tape, and these marks are arranged on the material tape 23 with a first division interval λ. Since the material tape 23 has the side stripes 24 on both sides of the mark 21 in the direction transverse to the measurement direction 11, the connected standard device 20 is obtained. The mark 21 is advantageously formed as a free space filled with air. However, the mark can also be filled with a non-ferromagnetic material, for example brass.

  The scanning device 30 is movable in the measurement direction 11 with respect to the standard device 20. The standard 20 is preferably fixed to the guide rail of the linear roller bearing, and the scanning device 30 is fixed to the corresponding guide carriage. A corresponding linear roller bearing is known from German Offenlegungsschrift 102007042796. The scanning device 30 includes an evaluation unit 34 which is preferably formed in the form of a dedicated electronic boat. The remaining part of the scanning device 30, in particular the transmission winding device 41, the reception coil 40, the switching device 70, and the operational amplifier 80 are arranged spatially close to the standard device 20. The evaluation unit 34 may have a larger spatial spacing with respect to the standard 20.

  The transmission winding device 41 and the reception coil 40 are each formed as a flat winding device. Although only one turn is written in FIG. 1, both the transmission winding device 41 and the reception coil 40 actually have a plurality of substantially parallel turns. In FIG. 1, the center line 25 is written in both the transmission winding device 41 and the standard device 20. Unlike those shown in FIG. 1, these two center lines 25 overlap each other, and the transmission winding device 41 and the reception coil 40 are arranged at a slight distance from the standard device 20 (FIGS. 6 and 6). (See FIG. 7). Thereby, the standard device 20 changes the inductive coupling between the transmission winding device 41 and the reception coil 40. That is, an AC voltage having an amplitude depending on the position of the scanning device 30 relative to the standard device 20 is induced in the receiving coil 40 by the AC supplied to the transmission winding device 41.

  The transmission winding device 41 is here formed as a meander structure, which surrounds a plurality of inherent transmission surfaces 42 arranged in a line in the measuring direction 11. The transmission winding device 41 includes a first group 44 and a second group 45 composed of a plurality of conductor paths 43 formed in a meandering line shape, and these conductor paths are a plurality of times along the measurement direction 11. Crossed. At a location indicated by reference numeral 46, the above-described plurality of conductor paths 43 are connected to each other so that the transmission winding device 41 is constituted by a single passing conductor path. The transmission winding device 41 can alternatively be grouped from a plurality of individual coils each surrounding a corresponding single transmission surface 42, which are selectively connected in series or in parallel. . When alternating current is supplied to the transmission winding device 41 by the alternating current source, electromagnetic transmission fields having substantially the same magnitude are generated on all the transmission surfaces 42, and the directions of the fields are adjacent to each other. The two transmission surfaces 42 are in the opposite direction. The alternating current source 31 is preferably a component of the evaluation unit 34.

  One transmission coil 40 is disposed on each transmission surface 42. An operational amplifier 80 is arranged in the spatial vicinity of the receiving coil 40, and this operational amplifier is preferably formed in a fully differential type. Two adjacent receiving coils 40 each have a constant second division interval δ in the measurement direction 11, which is, for example, 0.8 mm. The wiring of the operational amplifier 80 is shown in a very simplified manner in FIG. 1, and only two feedback resistors 85 and 86 characteristic of the fully differential operational amplifier 80 are shown. The first feedback resistor 85 connects the first input terminal 81 of the operational amplifier 80 and 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 and the second output terminal 84 of the operational amplifier 80.

  Since the first output terminal 83 and the second output terminal 84 are connected to the input side of the analog-digital converter 32, the analog-digital converter 32 can measure the corresponding electrical measurement voltage M. The corresponding digital value is transferred to the programmable digital calculator 33. The programmable digital calculator 33 and the analog-digital converter 32 are preferably components of the evaluation unit 34, which is most advantageously formed in the form of a microcontroller.

  The first input terminal 81 and the second input terminal 82 are connected to various receiving coils 40 via the switching device 70. The switching device 70 includes a first signal line 75 connected to the first input terminal 81 of the operational amplifier 80. Further, the second signal line 76 is connected to the second input terminal 82 of the operational amplifier 80. One terminal of each receiving coil 40 is connected to the third signal line 77. The other terminal of the receiving coil 40 is connected to either the first signal line 75 or the second signal line 76 via the corresponding switching means 71 and 72, respectively. Each switching means 71, 72, 73, 74 advantageously has a first state in which it has a first electrical resistance and each switching means has a second state in which it has a second electrical resistance. Here, the second electric resistance is at least 1000 times larger than the first electric resistance, and the first state and the second state can be switched by at least one switching means. . The assumption in the present invention is that the receiving coil 40 is not connected to the operational amplifier 80 in the second state of the corresponding switching means 71, 72. Preferably, semiconductor-based switching means 71, 72, 73, 74 are used. Thereby, for example, a first electrical resistance of 0.9Ω can be obtained, and a second electrical resistance that causes at least 60 dB of signal attenuation can be obtained. Corresponding switching means are described in the data sheet which can be taken out at the Internet address http://www.ti.com/lit/ds/symlink/ts5a623157.pdf as of 19 March 2015.

  FIG. 1 exemplarily shows seven reception coils 40, and each of these reception coils has an index n counted up along the measurement direction 11. It is clear that the measurement system 10 can have a much larger number, for example 30 receive coils 40. The receiving coils 40 having indexes n = 1, 3, 5, and 7 are connected to the first signal line 75 via the first switching means 71, respectively. The receiving coils 40 arranged between them and having indexes n = 2, 4, 6 and 6 are connected to the second signal line 76 via the second switching means 72, respectively. With the wiring described here, the two selected receiving coils are differentially connected in common, and these receiving coils are connected to the input side of the operational amplifier 80. Thereby, the external disturbance field which acts on the two receiving coils 40 in the same manner does not change the measurement voltage M. The correct differential connection between the two receiving coils depends on the winding direction of the associated receiving coils and which terminal is connected to the third signal line 77.

  The fourth switching means 74 connects the third signal line 77 and the first input terminal 81 of the operational amplifier 80. Accordingly, only one of the individual receiving coils 40 is connected to the input side of the operational amplifier 80, and this receiving coil is connected to the second signal line 76 via the second switching means 72. Moreover, when using each receiving coil 40 connected to the 1st signal track | line 75 via the 1st switching means 71, only the 3rd switching means 73 is connected. The third signal line 77 is connected to the second input terminal 82 of the operational amplifier 80 by the third switching means 73.

  The first to fourth switching means 71, 72, 73, 74 are preferably driven and controlled by a programmable digital calculator 33. The corresponding control line is not shown in FIG.

  FIG. 2 schematically shows a part of the standard device 20 according to the first embodiment of the present invention shown in FIG. A diagram plotting the voltage ratio k with respect to the position x is shown below the standard 20. The position x is a position of each receiving coil (reference numeral 40 in FIG. 1) with respect to the standard device 20. The voltage ratio k indicates the amplitude of the AC voltage induced in the receiving coil being observed. A value of 100% occurs when the receiving coil is completely on the ferromagnetic material. When the receiving coil is completely on the mark 21, this voltage ratio is approximately 0%. This is because the inductive coupling between the transmitter winding device and the receiver coil is very weak due to the absence of ferromagnetic material.

  In the first embodiment, since the mark outline 50 is formed in a rectangle, the virtual rectangle 60 described in the independent claim completely coincides with the mark outline 50. The virtual rectangle 60 has a first rectangular side 61, a second rectangular side 62, a third rectangular side 63, and a fourth rectangular side 64. The first rectangular side 61 and the second rectangular side 62 extend in parallel to the measurement direction 11, and the third rectangular side 63 and the fourth rectangular side 64 extend in a direction perpendicular to the measurement direction 11. Exist. An interval 65 between the first rectangular side 61 and the second rectangular side 62 is equal to the width of the mark 21. Since the interval 65 is configured to be slightly smaller than the width 27 of the material tape 23, two opposing side stripes 24 that integrate the material tape 23 remain. The interval 66 of the fourth rectangular side 64 of the third rectangular side 63 is the length of the mark 21. Here, this is slightly larger than an integer multiple of the first division interval λ. As can be seen from FIG. 1, the first division interval λ can be obtained by measuring the intervals of the third rectangular sides 63 of all the marks 21, for example, and the shortest interval among these intervals is It is equal to twice the division interval λ.

  An interval 66 to an internal interval (reference numeral 67 in FIG. 1) between two adjacent virtual rectangles 60 is a distance between two 50% values 12 of the voltage ratio k and the first division interval as accurately as possible. It is selected to be an integral multiple of λ. When the first division interval λ is, for example, 1.0 mm, the interval 66 can be, for example, 1.4 mm, and the above-described internal interval (reference numeral 67 in FIG. 1) is, for example, 0.6 mm.

  FIG. 3 schematically shows a part of a standard device 20 according to a second embodiment of the present invention. Since the mark outline 50 is formed in a parallelogram shape, the mark outline no longer completely coincides with the virtual rectangle 60. A virtual rectangle 60 is written by a broken line in FIG. The straight first outer peripheral portion 51 of the mark outline 50 is completely on the first rectangular side 61, and the first rectangular side 61 is longer than the first outer peripheral portion 51. The straight second outer peripheral portion 52 of the mark outline 50 is completely on the second rectangular side 62, and the second rectangular side 62 is longer than the second outer peripheral portion 52.

  The third rectangular side 63 is associated with a straight third outer peripheral portion 53 of the related mark outline 50, and this outer peripheral portion is completely disposed within the virtual rectangle 60. The fourth rectangular side 64 is associated with the linear fourth outer peripheral portion 54 of the related mark outline 50, and this outer peripheral portion is completely disposed within the virtual rectangle 60. The third outer peripheral portion 53 and the fourth outer peripheral portion 54 are arranged in parallel to each other, and they form an angle different from 90 ° with the measurement direction 11.

  A point 68 where the third rectangular side 63 and the mark outline 50 intersect is at a corner between the third outer peripheral portion 53 and the second outer peripheral portion 52. A point 69 where the fourth rectangular side 64 and the mark outline 50 intersect is at a corner between the fourth outer peripheral portion 54 and the first outer peripheral portion 51.

  As can be seen from the comparison between FIG. 2 and FIG. 3, in the second embodiment, the progress of the voltage ratio k at the position x in the two 50% value 12 regions is clearer than in the case of the first embodiment. The inclination is small. The distance 66 to the internal width (reference numeral 67 in FIG. 1) is again such that the distance 13 of the two 50% values of the voltage ratio k is as accurately as possible an integral multiple of the first division interval λ. Selected.

  FIG. 4 schematically shows a part of a standard device 20 according to a third embodiment of the present invention. The virtual rectangle 60 is written with a broken line in FIG. The straight first outer peripheral portion 51 of the mark outline 50 is completely on the first rectangular side 61, and the first rectangular side 61 is longer than the first outer peripheral portion 51. The straight second outer peripheral portion 52 of the mark outline 50 is completely on the second rectangular side 62, and the second rectangular side 62 is longer than the second outer peripheral portion 52.

  The third rectangular side 63 is associated with a third outer peripheral portion 53a of the mark outline 50 that is bent and extends outward. The fourth rectangular side 64 is associated with the fourth outer peripheral portion 54a of the mark outline 50 that is bent outward and extends. The third outer peripheral portion 53a and the fourth outer peripheral portion 54a are formed to be mirror-symmetric with each other. The third outer peripheral portion 53a and the fourth outer peripheral portion 54a each have exactly two lower portions 57, and these two lower portions form an angle of 90 ° or more. Two linear lower portions 57 corresponding to each other are in contact with each other at a corner 58. These corner portions 58 constitute points 68 and 69 where the third rectangular side 63 to the fourth rectangular side 64 and the mark outline 50 intersect.

  In the third embodiment, the progress of the voltage ratio k for the position x in the two 50% value 12 regions is substantially the same as in the second embodiment shown in FIG. The distance 66 to the internal width (reference numeral 67 in FIG. 1) is again such that the distance 13 of the two 50% values of the voltage ratio k is as accurately as possible an integral multiple of the first division interval λ. Selected.

  The mark outline 50 according to the third embodiment is generally formed mirror-symmetrically with respect to the center line 25 of the standard device 20. As a result, an error in scanning the standard device 20 is avoided.

  FIG. 5 schematically shows a part of a standard device 20 according to a fourth embodiment of the present invention. This embodiment relates to another deviation between the ideal signal shape for signal evaluation and the actual signal shape. The fourth embodiment shown in FIG. 5 is a variation of the first embodiment shown in FIG. 2, which is different from the second embodiment shown in FIG. 3 to the third embodiment shown in FIG. Combinations are also possible.

  On the lower side of FIG. 5, signal shapes that can be generated when only the first embodiment shown in FIG. 2 is used are written in broken lines. The solid line shows the signal shape which occurs according to the compensation means described below and is particularly suitable for simple signal evaluation. There are a total of three types of deviations 14a, 14b, 15a, 15b, 16 between these signal shapes, which will be described in detail below.

  If the individual coils to be observed are present completely on the ferromagnetic material of the material tape 23 with a large spacing with respect to the mark 21, a flat effect 16 may be observed. In this case, the signal amplitude is slightly higher than when the individual coils are completely on the ferromagnetic material of the material tape 23 at a small distance to the mark 21. The flat effect 16 can be dealt with by an auxiliary mark 21a formed with a very narrow width compared to the mark 21 having information. This auxiliary mark 21a is exactly located where the flat effect 16 is shown if there is no auxiliary mark 21a. The width of the auxiliary mark 21a is selected so that the flat effect 16 disappears.

  Overshoots 14a, 14b may occur if the individual coils to be observed are present on the ferromagnetic material of the material tape 23 slightly before or slightly behind the mark boundaries 53, 54. The overshoots 14a, 14b can be addressed by removing the ferromagnetic material in the corresponding region of the material tape 23. For this purpose, a fifth outer peripheral portion 55 of the mark outline 50 is provided on the first rectangular side 61 of the auxiliary mark 21a, and this outer peripheral portion is bent outwardly with respect to the measuring direction 11 and extends. The second rectangular side 62 is associated with at least one sixth outer peripheral portion 56 of the mark outline 50 of the auxiliary mark 21a, which extends outwardly with respect to the measurement direction 11.

  When the individual coil to be observed exists at a position where the mark 21 is slightly behind or just before the mark boundaries 53 and 54, the undershoots 15a and 15b may be observed. These undershoots 15a, 15b can be addressed by adding a ferromagnetic material to the corresponding region of the material tape 23. For this purpose, a fifth outer peripheral portion 55 of the mark outline 50 is provided on the first rectangular side 61 of the mark 21. The fifth outer peripheral portion is bent inward with respect to the measurement direction 11 and extends. The second rectangular side 62 of the mark 21 is associated with at least one sixth outer peripheral portion 56 of the mark outline 50, and the sixth outer peripheral portion is bent inward with respect to the measurement direction 11 and extends. ing.

  The fifth outer peripheral portion 55 and / or the sixth outer peripheral portion 56 may have at least one linear lower portion 57a as shown in the case of the overshoot 14b and the undershoot 15b in FIG. The fifth outer peripheral portion 55 and / or the sixth outer peripheral portion 56 may have a lower portion 57b that is curved without being bent, as shown in the case of the overshoot 14a and the undershoot 15a in FIG.

  FIG. 6 shows a schematic cross section of the position measuring apparatus 10 shown in FIG. 1, and the mark 21 is formed as a through portion 22. Correspondingly, the mark 21 penetrates the entire thickness 26 of the standard device 20. The mark contour 50 is formed substantially constant over the entire thickness 26 of the material tape 23. Due to the advantageous production by the photochemical etching method, various deviations can occur due to tolerances. The through-hole 22 is advantageously etched from the material tape 23 simultaneously from two opposite sides, so that the etching time is shortened.

  Further, in FIG. 6, the arrangement of the reception coil 40 and the transmission winding device 41 with respect to the standard device 20 can be seen. The receiving coil 40 and the transmitting winding device 41 are each formed as a flat winding device, which are preferably produced by photochemical etching. In FIG. 6, only a single layer is provided for each of the reception coil 40 and the transmission winding device 41, but a plurality of layers may be provided in order to increase the number of coil turns as much as possible. The individual layers are separated from each other by one insulating layer 47, which can be made of polyimide, for example. This plastic is electrically insulating and withstands high temperatures. If the reception coil 40 and / or the transmission winding device 41 each have a plurality of layers, these are preferably electrically connected to one another via a through hole. These through-holes penetrate one or more corresponding insulating layers.

  The sensor spacing 17 between the standard 20 and the unit including the receiving coil 40 and the transmitting winding device 41 is advantageously configured to be smaller, and most advantageously configured to be smaller than the first division interval λ.

  FIG. 7 shows a view corresponding to FIG. 6, and the mark 21 is configured as a recess 22a. The recess 22 a has a certain depth 22 b that is, for example, half the thickness 26 of the material tape 23. The recess 22a is preferably produced by a photochemical etching method, which is performed only from one side of the material tape 23. Since it is difficult to control the etching depth, and hence the depth 22b of the recess 22a, the through portion of FIG. 6 is advantageous.

  Refer to the description of FIG. 6 for other points. 6 and 7, the same reference numerals are given to the same or corresponding parts.

λ 1st division interval δ 2nd division interval M Measurement voltage k Voltage ratio x Position of individual receiver coils relative to standard 10 Position measurement system 11 Measurement direction 12 50% value of voltage ratio 13 Two 50% values of voltage ratio Distance 14a Overshoot 14b Overshoot 15a Undershoot 15b Undershoot 16 Flat effect 17 Sensor interval 20 Standard 21 Mark 21a Auxiliary mark 22 Through portion 22a Recess 22b Depth of recess 23 Material tape 24 Side stripe 25 Center line 26 Material tape The thickness of the material 27 The width of the material tape 30 The scanning device 31 The AC current source 32 The analog-digital converter 33 The programmable digital calculator 34 The evaluation unit 40 The reception coil 41 The transmission winding device 42 The transmission surface 43 The meandering wire conductor 44 45 Second Glue 46 Boundary portion between two groups of meandering linear conductor paths 47 Insulating layer 50 Mark outline 51 First outer peripheral portion 52 Second outer peripheral portion 53 Third outer peripheral portion 53a Third outer peripheral portion 54 Fourth outer peripheral portion 54a Fourth outer peripheral portion 55 fifth outer peripheral portion 56 sixth outer peripheral portion 57 linear lower portion 57a linear lower portion 57b lower portion curved without bending 58 corner 60 virtual rectangle 61 first rectangular side 62 second rectangular side 63 Third rectangular side 64 Fourth rectangular side 65 Spacing between first rectangular side and second rectangular side 66 Spacing between third rectangular side and fourth rectangular side 67 Inner method between two adjacent rectangles 68 A point where the third rectangular side and the mark outline intersect 69 A point where the fourth rectangular side and the mark outline intersect 70 switching device 71 first switching means 72 second switching means 73 third switch Ching means 74 Fourth switching means 75 First signal line 76 Second signal line 77 Third signal line 80 Operational amplifier 81 First input terminal of operational amplifier 82 Second input terminal of operational amplifier 83 First output terminal of operational amplifier 84 Second of operational amplifier Output terminal 85 First feedback resistor 86 Second feedback resistor

Claims (14)

A standard device (20) used in the position measurement system (10),
It is formed by a material tape (23) composed of a ferromagnetic material,
The material tape (23) is formed by being stretched along the measurement direction (11),
A plurality of marks (21, 21a) are arranged in a row on the material tape along the measurement direction (11),
Each of the plurality of marks (21) is constituted by a through portion (22) or a concave portion (22a) having a certain depth,
Each of the plurality of marks (21) has a mark outline (50),
A binary random number sequence is encoded by at least a part of the plurality of marks (21),
Each mark outline (50) is completely associated with the corresponding virtual rectangle (60), and the virtual rectangle (60) has first, second, third and fourth rectangular sides. (61, 62, 63, 64)
The first and second rectangular sides (61, 62) extend parallel to the measurement direction (11),
Each of the mark contours (50) has at least one linear first outer peripheral portion (51), and the first outer peripheral portion (51) overlaps with the corresponding first rectangular side (61). ,
Each of the mark outlines (50) has at least one linear second outer peripheral portion (52), and the second outer peripheral portion (52) overlaps with the corresponding second rectangular side (62). ,
The third and fourth rectangular sides (63, 64) overlap the corresponding mark contour (50) at points (68, 69), respectively.
In the standard device (20), the interval between the third rectangular sides (63) of two adjacent virtual rectangles (60) is an integral multiple of the first division interval (λ).
The internal spacing (67) between two adjacent virtual rectangles (60) is different from an integer multiple of the first division spacing (λ).
A standard device (20) characterized by that. Each of the mark outlines (50) completely overlaps the corresponding virtual rectangle (60),
Standard device (20) according to claim 1. The third rectangular side (63) is associated with a linear third outer peripheral portion (53) of the related mark outline (50),
The fourth rectangular side (64) is associated with a linear fourth outer peripheral portion (64) of the related mark outline (50),
The third and fourth outer peripheral portions (53, 54) are arranged in parallel to each other,
The third and fourth outer peripheral portions (53, 54) form an angle different from 90 ° with the measurement direction (11).
Standard device (20) according to claim 1. The third rectangular side (63) is associated with a third outer peripheral portion (53a) of the mark outline (50) that extends bent outward or inward,
The fourth rectangular side (64) is associated with a fourth outer peripheral portion (54a) of the mark contour (50) that extends bent outward or inward.
Standard device (20) according to claim 1. The third and fourth outer peripheral parts (53a, 54a) each have two linear lower parts (57), and the lower parts form an angle of 90 ° or more.
Standard device (20) according to claim 4. The two linear sub-portions (57) associated with each other touch each other at a corner (58) or with a predetermined radius,
Standard device (20) according to claim 5. The outer peripheral part of the mark outline (50) associated with the first and second rectangular sides (61, 62) is formed in a mirror-symmetric manner with respect to each other.
Standard device (20) according to any one of the preceding claims. The first rectangular side (61) is associated with at least one fifth outer peripheral portion (55) of the mark outline (50) that extends while being bent with respect to the measurement direction (11). ,
The second rectangular side (62) is associated with at least one sixth outer peripheral portion (56) of the mark outline (50) that extends while being bent with respect to the measurement direction (11). ,
Standard device (20) according to any one of the preceding claims. The fifth and / or sixth outer peripheral portion (55, 56) has at least one linear sub-portion (57a);
Standard device (20) according to claim 8. The fifth and / or sixth outer peripheral portion (55, 56) has at least one lower portion (57b) curved without bending;
Standard device (20) according to claim 8 or 9. The one outer peripheral part (51) of all the mark contours (50) is arranged in a line in the measuring direction (11);
The two outer peripheral portions (52) of all the mark contours (50) are arranged in a line in the measurement direction (11),
Standard device (20) according to any one of the preceding claims. The interval (66) between the third rectangular side (63) and the fourth rectangular side (64) is 20 times the first division interval (λ), which is the closest integer multiple of the first division interval (λ). Larger by between 50% and 50%,
Standard device (20) according to any one of the preceding claims. In a position measurement system (10) comprising a standard (20) according to any one of the preceding claims,
A scanning device (30) having at least five receiving coils (40) arranged in a line in the measuring direction (11) is provided;
The scanning device (30) includes a transmission winding device (41) that does not move relative to the reception coil (40).
The scanning device (30) is movable in the measuring direction (11) along the standard (20),
The reception coil (40), the transmission winding device (41), and the standard device (20) are connected to the transmission winding device (41) according to the position of the standard device (20) with respect to the scanning device (30). , Arranged so that a change occurs in the inductive coupling with the receiving coil (40),
A position measurement system (10) characterized in that. The transmission winding device (41) surrounds a plurality of unique transmission surfaces (42) arranged in a line in the measurement direction (11),
A maximum of one corresponding receiving coil (40) is arranged in one transmission surface (42),
The standard device according to any one of claims 1 to 13.

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