CN111351420A - Magnetic position sensing device and method - Google Patents

Abstract

The magnetic position sensing device and method utilizes the pattern of induction rule to produce induction voltage change according to the position change of alternating magnetic field of excitation element, and then utilizes the technical means of analyzing position by voltage value to analyze out the position of said excitation element.

Description

Magnetic position sensing device and method

technical field

The present invention relates to position sensing technology, in particular to a magnetic position sensing device and method.

Background technique

High-precision position detection components include optical scales and magnetic scales, etc., which are widely used in precision machinery industries (such as machine tools) and smart manufacturing industries (such as precision robotic arms), etc. The processing equipment often needs to process products in harsh environments , Compared with optical rulers, magnetic rulers have better anti-pollution ability and simple structure. In recent years, the research and development of high-end magnetic rulers has become increasingly active, and there is a trend to replace the market of middle-grade optical rulers.

However, the traditional magnetic scale encounters the bottleneck of the miniaturization of the magnetic pole width, and the detection stability problem of the position of the voltage phase difference analysis pattern due to the assembly control, resulting in the low accuracy and poor stability of the general magnetic scale. On the other hand, the magnetization takes time. The problem also makes high-order magnetic rulers less prone to scale up.

Therefore, how to effectively improve the time-consuming magnetization, the difficulty in controlling the installation accuracy, and the limited production length is one of the urgent issues to be solved in the current industry.

public content

In order to overcome the shortcomings of the prior art, the present invention provides a magnetic position sensing device, comprising: an excitation element, which generates an alternating magnetic field; an induction ruler, which is formed with a pattern, and the pattern is generated according to the change of the alternating magnetic field an induced voltage; and a position analysis element, which extracts the induced voltage to resolve the position of the excitation element on the induction ruler according to the induced voltage.

The present invention also provides a magnetic position sensing method, comprising: forming a pattern on an induction ruler; causing an excitation element to generate an alternating magnetic field; using the pattern of the induction ruler to generate an induced voltage according to the change of the alternating magnetic field; and using a The position analysis element extracts the induced voltage, and analyzes the position of the excitation element on the induction ruler according to the induced voltage.

It can be seen from the above that the present invention utilizes the pattern of the induction ruler to generate an induced voltage with the change of the position of the alternating magnetic field of the exciting element, and then uses the technical means of analyzing the position of the voltage value to improve the position detection accuracy and stability, as well as the rotation of the metal wire pattern. The printing process is easy to scale up and other advantages, so as to solve the problems of time-consuming magnetization, difficult control of installation accuracy and limited production length encountered in the prior art using magnetic pole pattern sensing and voltage phase difference analysis.

Description of drawings

FIG. 1 is a schematic diagram of a first embodiment of the disclosed magnetic position sensing device;

2 is a schematic diagram of an excitation element of a first embodiment of the disclosed magnetic position sensing device;

3 is a schematic diagram of a position resolving element of the first embodiment of the magnetic position sensing device of the present disclosure;

4 is a schematic diagram of an induced voltage signal processing unit of the first embodiment of the magnetic position sensing device of the present disclosure;

5A is a schematic diagram of a pattern of a sensing ruler of the first embodiment of the magnetic position sensing device of the present disclosure;

5B to 5C are schematic diagrams of signal processing of the induced voltage of the first embodiment of the magnetic position sensing device of the present disclosure;

5D is a schematic diagram of a magnetic position sensing diagram of the first embodiment of the disclosed magnetic position sensing device;

5E is a schematic diagram of the relationship between the square wave pattern and the processing voltage of the first embodiment of the disclosed magnetic position sensing device;

5F is an enlarged schematic diagram of a turning point of processing voltage of the first embodiment of the disclosed magnetic position sensing device;

6A is a schematic diagram of a pattern of a sensing ruler of the second embodiment of the magnetic position sensing device of the present disclosure;

6B is a schematic diagram of a magnetic position sensing diagram of the second embodiment of the disclosed magnetic position sensing device;

6C is a schematic diagram of an analysis section of the second embodiment of the disclosed magnetic position sensing device;

FIG. 7 is a schematic flowchart of the first embodiment of the magnetic position sensing method of the present disclosure; and

FIG. 8 is a schematic flowchart of step S74 of the first embodiment of the magnetic position sensing method of the present disclosure.

[Description of Symbols of Main Elements of the Embodiments of the Present Disclosure in the Drawings]

1 Magnetic position sensing device

10 Exciting element

20 sensor ruler

21 Front

22 reverse

30, 30' pattern

31 Square Wave Graphics

31′ first figure

32 Second Graphic

40 Position Resolution Elements

41 Induced voltage signal processing unit

42 Induced voltage analysis position unit

61 Square wave area

62 Negative square wave area

63 Alternating magnetic field

101 Magnetically conductive part

102 Winding section

103 AC power supply unit

104 First magnetic pole part

105 Second magnetic pole part

106 Openings

311 Processing voltage

311' first processing voltage

313, 313′ The first peak and valley level

314, 314' first vertical part

315, 315′ first peak level

321 Second processing voltage

323 Second peak and valley level

324 Second Vertical Section

325 Second Peak Level

411 Filter

412 Envelope Detector

511 First non-turning curve section

512 First inflection curve section

513 First rising line segment

514 First descending segment

515 First Mountain Area

516 First trough area

521 Second non-turning curve section

522 Second inflection curve section

523 Second ascending segment

524 Second descending segment

525 Second Peak Area

526 Second trough area

B wave crest turning area

X distance

V _S , V _S1 , V _S2 induced voltage

_{VP, VP1 , VP2} handle voltage

Steps S71～S74, S81～S82.

Detailed ways

The embodiments of the present disclosure are described below through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the content disclosed in this specification.

It should be noted that the structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the contents disclosed in the specification for the understanding and reading of those skilled in the art, and are not used to limit the conditions for the implementation of the present disclosure. Therefore, it has no technical substantive significance, and any modification of the structure, the change of the proportional relationship or the adjustment of the size should still fall within the scope of the disclosure without affecting the effect that the disclosure can produce and the purpose that can be achieved. The technical content must be within the scope of coverage. At the same time, the terms such as "first" and "second" quoted in this specification are only for the convenience of description and clarity, and are not used to limit the scope of implementation of the present disclosure. If the technical content is not substantially changed, it should be regarded as the scope in which the present disclosure can be implemented.

FIG. 1 is a schematic diagram of a first embodiment of a magnetic position sensing device 1 of the present disclosure. As shown in the figure, the magnetic position sensing device 1 includes an excitation element 10, which is applied with an AC power source to generate an alternating magnetic field; an induction ruler 20, which is formed with a pattern 30, and the pattern 30 generates an induced voltage with the change of the alternating magnetic field; and a position analyzing element 40 , which is connected with the sensing ruler 20 to read the induced voltage generated by the sensing ruler 20 , and analyze the position of the excitation element 10 on the sensing ruler 20 according to the induced voltage.

In one embodiment, the pattern 30 of the sensing ruler 20 is formed of metal wires.

In one embodiment, the pattern 30 of the sensor ruler 20 is a periodic waveform pattern, and both ends of the periodic waveform pattern are connected to the position analysis element 40 , so that the position analysis element 40 can read the pattern 30 as the pattern 30 alternates. This induced voltage is generated by changes in the magnetic field.

FIG. 2 is a side view of the excitation element 10 of the first embodiment of the present disclosure. As shown in the figure, the excitation element 10 includes a magnetic conductive portion 101 , a winding portion 102 , an AC power supply unit 103 , a first magnetic pole portion 104 , a second magnetic pole portion 105 and an opening 106 .

The magnetic conductive portion 101 is annular with an opening 106 , the first magnetic pole portion 104 and the second magnetic pole portion 105 are located at both ends of the magnetic conductive portion 101 , the opening 106 is located between the first magnetic pole portion 104 and the second magnetic pole portion 105 , and The winding portion 102 is a coil structure and is wound on the magnetic conductive portion 101 . At the same time, the excitation element 10 moves on the pattern 30 of the induction scale 20 through the opening 106 , or the excitation element 10 is fixed so that the induction scale 20 moves in the opening 106 .

The AC power supply unit 103 applies the AC power to the winding portion 102 to generate the alternating magnetic field, so that the pattern 30 of the sensing ruler 20 changes with the alternating magnetic field to generate the induced voltage.

FIG. 3 is a schematic diagram of the position analysis element 40 of the magnetic position sensing device 1 of the present disclosure. As shown in the figure, the position analysis element 40 includes an induced voltage signal processing unit 41, which is connected to the pattern 30 on the sensor ruler 20, so as to read the induced voltage V _S generated by the pattern 30 with the change of the alternating magnetic field, and respond to the The induced voltage _VS is subjected to signal processing of filtering and detection to obtain the processing voltage _VP ; and the induced voltage analysis position unit 42 is connected to the induced voltage signal processing unit 41 to receive the processing voltage _VP , and according to the processing voltage The period of _VP corresponds to the length on the X-coordinate and is equal to the relationship between the period of the pattern 30 on the sensing scale 20 and the distance on the X-coordinate to resolve the position of the excitation element 10 on the sensing scale 20 .

FIG. 4 is a schematic diagram of the first embodiment of the induced voltage signal processing unit 41 of the present disclosure. As shown in the figure, the induced voltage signal processing unit 41 includes a filter 411, which filters the induced voltage V _S to filter out the carrier frequency of the AC power source in the induced voltage V _S ; and an envelope detector (envelope detector). _A detector 412 is connected to a filter 411 to detect the induced voltage VS with the carrier frequency filtered out, so as to obtain the processing voltage _VP .

In this embodiment, the filter 411 is a low-pass filter.

In this embodiment, the induced voltage signal processing unit 41 further includes: a first amplifier (amplifier, not shown), the output end of the first amplifier is connected to the input end of the filter 411 , and the input end of the first amplifier is connected to the input end of the filter 411 . The pattern 30 of the induction ruler 20 is connected to obtain the induced voltage generated by the pattern 30 with the change of the position of the alternating magnetic field from the induction ruler 20, and the induced voltage is amplified and output to the filter 411, but this is not the case. limit.

In the present embodiment, the induced voltage signal processing unit 41 further includes: a level shifter (levelshifter, not shown), which is connected to the envelope detector 412 and transmits the processing voltage V after the signal processing of filtering and detection is completed. _P performs a level shift process to obtain the level required by the processing voltage _VP for subsequent operations (here refers to a voltage level); and a second amplifier (not shown), which is shifted from the level The device is connected to amplify and output the processing voltage _VP after the level shift processing is completed to the induced voltage analysis position unit 42, but not limited to this.

In this embodiment, the position analysis element 40 further includes: an analog digital converter (not shown), which is located between the induced voltage signal processing unit 41 and the induced voltage analysis position unit 42 to convert the induced voltage signal The processing voltage _VP obtained by the processing unit 41 is converted into a processing voltage _VP of a digital signal and sent to the induced voltage analyzing and positioning unit 42, but not limited thereto.

FIG. 5A is a schematic diagram of a first embodiment of the pattern 30 of the sensor ruler 20 of the present disclosure. As shown in the figure, the pattern 30 of the first embodiment is a square wave pattern 31 and is only formed on one of the front side 21 or the back side 22 opposite to the front side 21 of the sensor ruler 20 shown in FIG. The first peak-to-valley horizontal portions 313 , a plurality of first vertical portions 314 and a plurality of first peak-top horizontal portions 315 are formed, and the line width of the square wave pattern 31 is 1 mm. The line spacing (A) is 4mm, and the period (T _D ) of the square wave pattern 31 corresponds to a distance on the X coordinate of 8mm, and the area where the opening of the square wave pattern 31 faces downward is the square wave area 61 and the opening faces upward. The area of is the negative square wave area 62 .

FIG. 5B is a schematic waveform diagram of the induced voltage of the first embodiment generated by the position analyzing element 40 analyzing the pattern 30 of the present disclosure as the alternating magnetic field changes. As shown in the figure, after the excitation element 10 moves a distance ΔX on the sensing ruler 20, the movement of the distance ΔX will drive the change of the alternating magnetic field, so that the pattern 30 on the sensing ruler 20 senses the change of the alternating magnetic field to generate the corresponding change in the alternating magnetic field. Change in induced voltage (change in amplitude of waveform). Therefore, the relationship between the induced voltage V _S1 and the induced voltage V _S2 is the relationship between the moving distance ΔX of the exciting element 10 on the inductive scale 20 , and since the induced voltage includes the amplitude of the carrier frequency of the AC power source 103 , the induced voltage V _S1 moves by the distance ΔX. There will be a change in amplitude from ΔX to the induced voltage V _S2 .

FIG. 5C is a schematic diagram of the processing voltage obtained after the induced voltage in FIG. 5B is analyzed by the position analysis element 40 . As shown in the figure, after the induced voltages V _S1 and V _S2 with amplitude changes are filtered and detected by the induced voltage signal processing unit 41 , the processed voltages V _P1 and V _P2 without the carrier frequency are obtained. It corresponds to the induced voltage, so the relationship ΔV between the processing voltage V _P1 and the processing voltage V _P2 is also the change in the ΔX distance.

After the excitation element 10 generates the alternating magnetic field, the induced voltage signal processing unit 41 performs signal processing of filtering and detection on the induced voltage V _S generated by the pattern 30 with the change of the alternating magnetic field, so as to obtain the signal as shown in FIG. 5D . After the processing voltage 311 in the shape of a triangle wave is displayed, the induced voltage analysis location unit 42 extracts all the sections of the processing voltage 311 in the shape of a triangle wave shown in FIG. 5D as the analysis section, and uses the processing voltage of the analysis section The period (T _L ) corresponds to the length on the X coordinate, and is represented by the period (T _D ) of the square wave pattern 31 corresponding to the distance unit on the X coordinate, and then let the processing voltage of the analysis section vary with the distance unit. The change is the moving distance of the excitation element 10 on the induction ruler 20 , and then the position of the excitation element 10 on the induction ruler 20 is analyzed from the analysis section.

It should be understood that, since the processing voltage V _P1 corresponds to the induced voltage V _S1 , and the variation of the induced voltage V _S1 is relative to the distance that the excitation element 10 moves on the pattern 30 , therefore, the period of the processing voltage shown in FIG. 5D (T _L ) corresponds to the length on the X coordinate in terms of the period (T _D ) of the pattern 30 corresponding to the distance unit on the X coordinate, X=S×T _L +X ₀ =S×T _L +(V _t −V ₀ )/m, where X is the position of the excitation element 10 on the induction ruler 20, S is the period number of the analysis section (0, 0.5, 1, 1.5, ...), and T _L is the period of the analysis section distance, X ₀ is the distance from the S-th cycle processing voltage to X, V _t is the processing voltage value, V ₀ is the S-th cycle linear starting voltage value, and m is the slope value of (X, V _t ).

FIG. 5E is a schematic diagram of the relationship between the square wave pattern 31 on the sensor ruler 20 and the processing voltage 311 according to the first embodiment of the present disclosure. As shown in the figure, the square wave pattern 31 generates a processing voltage 311 corresponding to a triangular waveform with the change of the position of the alternating magnetic field 63 of the exciting element 10. FIG. 5F shows the processing voltage 311 of a triangular waveform at the turning area of the peak and the trough (as shown in FIG. 5F ). The wave crest transition area B) shown in 5E presents an arc-like shape.

FIG. 6A is a schematic diagram of a pattern 30 ′ of the second embodiment of the magnetic position sensing device 1 of the present disclosure. As shown in the figure, the difference between the present embodiment and the first embodiment lies in the pattern 30 ′, so the difference will be described below, and the similarities will not be repeated. The pattern 30 ′ of this embodiment includes a first pattern 31 ′ and a second pattern 32 . The first pattern 31 ′ is formed on the front surface 21 of the sensor ruler 20 shown in FIG. On the reverse side 22 of the sensor ruler 20, the first pattern 31' and the second pattern 32 are located on the same horizontal line, and the patterns of the first pattern 31' and the second pattern 32 are the same and differ from each other by 1/2 line spacing (A ) or 1/4 period (T _D ), wherein the first pattern 31 ′ is defined by a plurality of first peak-valley horizontal portions 313 ′, a plurality of first vertical portions 314 ′ and a plurality of first peak-top horizontal portions 315 ′ The square wave pattern formed, the second pattern 32 is a square wave pattern formed by a plurality of second peak-valley horizontal portions 323 , a plurality of second vertical portions 324 and a plurality of second peak-top horizontal portions 325 .

After the first pattern 31 ′ of the second embodiment generates a first induced voltage with the change of the alternating magnetic field and the second pattern 32 generates a second induced voltage with the change of the alternating magnetic field, each of the induced voltages is then passed through the induced voltage signal processing unit 41 , two processing voltages like a triangle wave are obtained which are located on the same horizontal line and differ from each other by 1/4 cycle as shown in FIG. 6B , the first processing voltage 311 ′ corresponds to the first pattern 31 ′ and the second processing voltage 321 corresponds to the first In the two graphs 32 , the first processing voltage 311 ′ and the second processing voltage 321 are both triangular-like waveforms. As shown in FIG. 6A , the first graph 31 ′ and the second graph 32 differ from each other by 1/2 line spacing (A) or 1/4 period (TD), therefore, the first processing voltage 311 ′ and the second processing voltage 321 are also different from each other by 1/4 period (TD).

The waveforms of the first non-turning curve section 511 of the first processing voltage 311 ′ and the second non-turning curve section 521 of the second processing voltage 321 are non-inversion parts, so the slopes approach a constant value, and the first processing voltage 311 The waveforms of the first turning curve section 512 of ' and the second turning curve section 522 of the second processing voltage 321 are inversion parts, so the slopes cannot approach a constant value due to the exchange of positive and negative slopes. The first non-inflection curve segment 511 includes a first ascending line segment 513 and a first descending line segment 514, the second non-inflection curve segment 521 includes a second ascending line segment 523 and a second descending line segment 524, and the first inflection curve segment 512 includes The first peak area 515 and the first trough area 516 , and the second inflection curve section 522 includes the second peak area 525 and the second trough area 526 .

Next, the induced voltage analysis position unit 42 is used to deduct the first peak area 515 and the first valley area 516 of the first processing voltage 311 ′, and only the first rising line segment 513 and the first falling line segment 514 are extracted. Similarly, the induced voltage analysis position The unit 42 deducts the second peak region 525 and the second valley region 526 of the second processing voltage 321, and only extracts the second rising line segment 523 and the second falling line segment 524 (as shown by the thick line in FIG. 6B ), so that the first processing All the rising line segments and falling line segments of the voltage 311 and the second processing voltage 321 form an analysis section of the triangular wave shown in FIG. 6C , and the period (T _L ) of the processing voltage in the analysis section corresponds to the X block The marked length is represented by the period (T _D ) of the first pattern 31 ′ or the second pattern 32 corresponding to the distance unit on the X coordinate, so that the change of the processing voltage of the analysis section with the distance unit is The moving distance of the exciting element 10 on the sensing ruler 20 is used to complete the position sensing waveform as shown in FIG.

It should be understood that, since the first pattern 31 ′ corresponds to the first processing voltage 311 ′ and the second pattern 32 corresponds to the second processing voltage 321 , the period (T _L ) of the processing voltage shown in FIG. 6C corresponds to the X coordinate The length is expressed in units of distance corresponding to the period (T _D ) of the first pattern 31 ′ or the second pattern 32 corresponding to the X coordinate.

TD或

)时，从第一处理电压311′与第二处理电压321的非转折曲线区段的分析区段中，可取得激磁元件10的位置感知的最佳往覆精度误差范围及定位精度，其最佳往覆精度误差范围为±0.003mm及最佳定位精度为0.01mm。Since the induced voltage analysis position unit 42 only extracts the non-turning curve segments 511 and 521 whose slopes approach a constant value, the pattern 30 ′ of the second embodiment can effectively improve the performance compared with the pattern 30 of the first embodiment. The accuracy of the position perception of the excitation element 10, wherein, in this second embodiment, returning to FIG. 6A, when the period (T _D ) of the first pattern 31 ′ and the second pattern 32 corresponds to the distance on the X coordinate is 8mm, the line spacing (A) is 4mm and the line width is 1mm, and the first pattern 31' and the second pattern 32 are both misaligned by 2mm (

TD or

), from the analysis section of the non-turning curve section of the first processing voltage 311 ′ and the second processing voltage 321 , the best reciprocating accuracy error range and positioning accuracy of the position sensing of the exciting element 10 can be obtained. The best reciprocating accuracy error range is ±0.003mm and the best positioning accuracy is 0.01mm.

In the second embodiment, as shown in FIG. 6C , the induced voltage analysis position unit 42 further includes providing a position conversion algorithm to directly exchange the position (X) of the excitation element 10 on the induction ruler 20 , where X=S×1/ 2(T _L )+X ₀ =S×1/2( _TL )+(V _t -V ₀ )/m, where X is the position of the excitation element 10 on the induction ruler 20 , and S is the position of the analysis section. The number of cycles (0, 0.5, 1, 1.5, ...), _TL is the distance of the cycle of the analysis section, X ₀ is the distance from the S-th cycle processing voltage to X, V _t is the processing voltage value, and V ₀ is The linear starting voltage value of the S-th cycle, m is the slope value of (X, V _t ), and there are many position conversion algorithms, which are not limited to the above. After several cycles _TL are calculated, S×1/2( _TL ) can be obtained. The slope value m is known from the rising and falling sections of the triangular wave, and the linear starting voltage value V ₀ of the S-th cycle is known. , after measuring the processing voltage value V _t , the distance X ₀ from the induced voltage in the S-th cycle to X can be calculated, thereby the position X of the excitation element 10 on the induction ruler 20 can be obtained.

FIG. 7 is a schematic flowchart of the first embodiment of the magnetic position sensing method of the present disclosure (ie, the single-sided pattern ruler in FIG. 5A ). As shown in the figure, it includes the following steps: in step S71, forming a pattern 30 on an induction ruler 20; in step S72, making an excitation element 10 generate an alternating magnetic field; in step S73, using the The pattern 30 generates an induced voltage with the change of the alternating magnetic field; and in step S74 , a position analysis element 40 is used to extract the induced voltage, and the position of the excitation element 10 on the induction ruler 20 is analyzed according to the induced voltage.

In step S72, an AC power supply unit 103 applies AC power to the excitation element 10 to generate the alternating magnetic field.

FIG. 8 is a flow chart of the steps of this step S74. As shown in the figure, the following steps are included: in step S81, an induced voltage signal processing unit 41 is made to read the induced voltage Vs generated by the pattern 30 according to the change of the alternating magnetic field from the sensor ruler 20, and the induced voltage _Vs The voltage _VS is subjected to signal processing of filtering and detection to obtain the processing voltage _VP ; and in step S82, an induced voltage analysis position unit 42 is made to read the processing voltage _VP , which corresponds to the X block according to the period of the processing voltage The length on the scale is equal to the relationship between the period of the pattern 30 on the induction ruler 20 and the distance on the X coordinate, so as to resolve the position of the excitation element 10 on the induction ruler 20 from the processing voltage.

In this embodiment, the step S81 includes: filtering the induced voltage with a low-pass filter (ie, the filter 411 in FIG. 4 ), so as to filter out the carrier frequency of the AC power source in the induced voltage _VS ; Use an envelope detector (that is, the envelope detector 412 in FIG. 4 ) to detect the induced voltage _VS filtered out of the carrier frequency to obtain the processing voltage _VP .

In the first embodiment, in step S71, the pattern 30 of the square wave pattern 31 is formed on the front side 21 of the sensor ruler 20 or one of the sides of the back side 22 opposite to the front side 21; the induced voltage signal processing unit in step S81 is made 41 Read the induced voltage generated by the square wave pattern 31 according to the change of the alternating magnetic field from the induction ruler 20, and perform signal processing of filtering and detection on the induced voltage V _S to obtain the processing voltage 311 in the form of a triangular wave; And make the induced voltage analysis position unit 42 in the step S82 read the processing voltage 311 in the form of a triangular wave, and make all sections of the processing voltage 311 in the triangular wave form an analysis section, and according to the period of the processing voltage Corresponding to the relationship that the length on the X-coordinate is equal to the period of the square wave pattern 31 on the induction ruler 20 and the distance on the X-coordinate, the period (T _L ) of the processing voltage of the analysis section corresponds to the X-coordinate The upper length is represented by the period (T _D ) of the square wave pattern 31 corresponding to the distance unit on the X-coordinate, so as to complete the position sensing waveform shown in FIG. 5B , and make the processing voltage of the analysis section vary with the distance unit. The change of is the moving distance of the excitation element 10 on the induction ruler 20 , and then the position of the excitation element 10 on the induction ruler 20 is analyzed from the analysis section.

The present disclosure further provides a second embodiment of the magnetic position sensing method (that is, the double-sided pattern ruler in FIG. 6A ). The difference between this embodiment and the aforementioned first embodiment lies in the pattern 30 ′, so the following will describe the difference without Repeat the same. In step S71, patterns with the same horizontal line are formed on the front side 21 and the back side 22 of the sensor ruler 20, respectively, and the patterns are the first pattern 31' and the second pattern 32 of the square wave pattern and differ from each other by 1/2 line spacing or 1/4 cycle (as shown in FIG. 6A ); make the induced voltage signal processing unit 41 in step S81 perform the signal processing on the induced voltages generated by the changes of the patterns with the alternating magnetic field, so as to obtain signals at the same The two processing voltages (ie, the first processing voltage 311 ′ and the second processing voltage 321 ) which are horizontal lines and differ from each other by 1/4 cycle in the form of a triangular wave; and cause the induced voltage analysis position unit 42 in the step S82 to read the Two triangular-like processing voltages (ie, the first processing voltage 311 ′ and the second processing voltage 321 ) are extracted, and the two processing voltages that are similar to the triangular wave (ie, the first processing voltage 311 ′ and the second processing voltage 321 ) are extracted The non-turnover curve section (ie, the first non-turnover curve section 511 and the second non-turnover curve section 521 ), to obtain the analysis section of the forward and reverse staggered triangular wave (as shown in FIG. 6C ), and according to the processing voltage The period corresponding to the length on the X coordinate is equal to the relationship between the period of the first pattern 31' or the second pattern 32 on the induction ruler 20 corresponding to the distance on the X coordinate, the period of the processing voltage of the analysis section ( T _L ) corresponds to the length on the X-coordinate and is represented by the cycle (TD) of the first pattern 31 ′ or the second pattern 32 corresponding to the distance unit on the X-coordinate, so as to complete the position-aware waveform diagram as shown in FIG. 6C , The change of the processing voltage of the analysis section with the distance unit is the moving distance of the excitation element 10 on the induction ruler 20 , and the position of the excitation element 10 on the induction ruler 20 is analyzed from the analysis section.

In the first embodiment of the method (that is, the single-sided pattern ruler in FIG. 5A ), the step S82 further includes providing a position conversion algorithm to directly exchange the position of the excitation element 10 on the sensing ruler 20 from the position sensing waveform diagram. Position (X), where X=S×T _L +X ₀ =S× _TL +(V _t -V ₀ )/m, where X is the position of the excitation element 10 on the induction ruler 20 , and S is the analysis The cycle number of the segment (0, 0.5, 1, 1.5, ...), _TL is the distance of the cycle of the analysis segment, X ₀ is the position of the processing voltage in the S-th cycle, V _t is the processing voltage value, and V ₀ is the linear starting voltage value of the S-th cycle, m is the slope value of V _t , and there are many position conversion algorithms, which are not limited to the above.

In the second embodiment of the method (that is, the double-sided pattern ruler in FIG. 6A ), the step S82 further includes providing a position conversion algorithm to directly replace the excitation element 10 on the sensing ruler 20 from the position sensing waveform diagram. Position (X), where X=S×1/2(T _L )+X ₀ =S×1/2( _TL )+(V _t −V ₀ )/m, where X is the excitation element 10 at The position on the sensing ruler 20, S is the cycle number of the analysis section (0, 0.5, 1, 1.5, ...), _TL is the distance of the cycle of the analysis section, X ₀ is the position of the processing voltage in the S-th cycle , V _t is the processing voltage value, V ₀ is the linear starting voltage value of the S-th cycle, m is the slope value of Vt, and there are many position conversion algorithms, which are not limited to the above.

It can be known from the above that the present disclosure uses the pattern of the induction ruler to generate an induced voltage with the position change of the alternating magnetic field of the excitation element, and then uses the technical means of analyzing the position of the voltage value to improve the accuracy and stability of position detection, and the metal wire The pattern transfer process has the advantages of being easy to scale up, so as to solve the problems of time-consuming magnetization, difficult control of installation accuracy and limited production length encountered in the prior art using magnetic pole pattern sensing and voltage phase difference analysis.

Claims (14)

1. A magnetic position sensing device, comprising:

an excitation element for generating an alternating magnetic field;

an induction ruler, which is formed with a pattern and the pattern generates an induction voltage according to the change of the alternating magnetic field; and

and the position analyzing element extracts the induction voltage so as to analyze the position of the excitation element on the induction scale according to the induction voltage.

2. A magnetic position sensing device according to claim 1, wherein the pattern of the sensing ruler is formed of metal wires.

3. The magnetic position sensing device of claim 1, further comprising:

an AC power supply unit for applying AC power to the exciting element to generate the alternating magnetic field.

4. A magnetic position sensing device according to claim 3, wherein the position resolving element further comprises:

an induced voltage signal processing unit which reads the induced voltage and sequentially performs signal processing of filtering and detecting on the induced voltage to obtain a processed voltage, wherein the carrier frequency of the alternating current power supply contained in the induced voltage is filtered by the filtering; and

the induced voltage analyzing position unit analyzes the position of the exciting element on the induction scale according to the relation that the length of the period of the processing voltage on the X coordinate is equal to the distance of the period of the pattern on the induction scale on the X coordinate.

5. The magnetic position sensor according to claim 4, wherein the pattern on the sensing scale is a square wave pattern and is located on the front or back of the sensing scale, so that the induced voltage signal processing unit processes the induced voltage generated by the pattern changing with the alternating magnetic field to obtain the processing voltage in a triangle-like wave, and the induced voltage analyzing location unit extracts all sections of the processing voltage in a triangle-like wave to obtain an analyzing section, and analyzes the position of the excitation element on the sensing scale from the analyzing section according to the relationship that the period of the processing voltage corresponds to the distance on the X-coordinate, the length of the processing voltage on the X-coordinate is equal to the period of the pattern on the sensing scale on the X-coordinate.

6. The magnetic position sensor according to claim 4, wherein the front and back surfaces of the sensing ruler have patterns on the same horizontal line, each of the patterns is a square wave pattern and differs from each other by 1/2 line distance or 1/4 period, so that the induced voltage signal processing unit performs signal processing on the induced voltage generated by each of the patterns according to the variation of the alternating magnetic field, so as to obtain two triangular-like processing voltages on the same horizontal line and differing from each other by 1/4 period, and the induced voltage analyzing unit extracts non-inflected curve sections of the two triangular-like processing voltages to obtain forward and backward staggered triangular analysis sections, and based on the relationship that the length of the processed voltage on the X coordinate is equal to the distance of the pattern on the sensing ruler on the X coordinate, and analyzing the position of the excitation element on the induction scale from the analysis section.

7. The magnetic position sensing device according to claim 4, wherein the induced voltage signal processing unit obtains the processed voltage without the carrier frequency after performing signal processing of filtering and detecting the induced voltage with amplitude variation, and the voltage variation of the processed voltage corresponds to the variation of the moving distance of the laser element on the sensing scale.

8. A magnetic position sensing device according to claim 1, wherein the excitation element further comprises a first magnetic pole portion, a second magnetic pole portion, and an opening between the first magnetic pole portion and the second magnetic pole portion, such that the excitation element moves the pattern on the sensing ruler through the first magnetic pole portion and the second magnetic pole portion into the opening.

9. A method of magnetic position sensing, comprising:

forming a pattern on an induction ruler;

making an excitation element generate an alternating magnetic field;

generating an induction voltage according to the change of the alternating magnetic field by using the pattern of the induction ruler; and

a position analyzing element is used for extracting the induction voltage, and the position of the exciting element on the induction ruler is analyzed according to the induction voltage.

10. The method of claim 9, wherein the alternating magnetic field is generated by an ac power supply unit applying ac power to the excitation element.

11. The method of claim 10, wherein the step of the position analyzing element analyzing the position of the exciting element on the sensing scale comprises:

an induced voltage signal processing unit reads the induced voltage generated by the pattern according to the change of the alternating magnetic field from the induction ruler, and then sequentially carries out signal processing of filtering and detecting on the induced voltage to obtain a processed voltage, wherein the carrier frequency of the alternating current power supply contained in the induced voltage is filtered by the filtering; and

and analyzing the position of the exciting element on the induction scale from the processing voltage by an induction voltage analyzing position unit according to the relation that the length of the period of the processing voltage on the X coordinate is equal to the distance of the period of the pattern on the induction scale on the X coordinate.

12. The method as claimed in claim 11, wherein a square-wave pattern is formed on the front or back surface of the induction ruler, the induced voltage signal processing unit processes the induced voltage generated by the pattern according to the variation of the alternating magnetic field to obtain the processing voltage in a triangular wave form, the induced voltage analyzing position unit extracts all sections of the processing voltage in a triangular wave form to obtain an analyzing section, and the position of the exciting element on the induction ruler is analyzed from the analyzing section according to the relationship that the period of the processing voltage corresponds to the distance on the X coordinate corresponding to the length on the X coordinate and the period of the pattern on the induction ruler.

13. The magnetic position sensing method of claim 11, wherein the front and the back of the sensing ruler are respectively formed with patterns on the same horizontal line, each of the patterns is a square wave pattern and has a difference of 1/2 line distance or 1/4 period, so that the induced voltage signal processing unit processes the induced voltage generated by each of the patterns along with the change of the alternating magnetic field to obtain two triangular-like processing voltages on the same horizontal line and having a difference of 1/4 period, and the induced voltage analyzing unit extracts the non-turning curve sections of the two triangular-like processing voltages to obtain the analysis sections of the front and back staggered triangular waves, and according to the relationship that the period of the processing voltage corresponds to the distance on the X coordinate equal to the period of the pattern on the sensing ruler, and analyzing the position of the excitation element on the induction scale from the analysis section.

14. The magnetic position sensing method of claim 11, wherein the induced voltage signal processing unit performs signal processing of filtering and detecting the induced voltage having a variation in amplitude to obtain the processed voltage without the carrier frequency, and a variation in voltage of the processed voltage corresponds to a variation in a moving distance of the laser element on the induction scale.

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