TWI689704B - Magnetic position sensing device and method - Google Patents

Abstract

A magnetic position sensing device and method for generating an induced voltage change by changing a relative position of an stimulated magnetic component and a pattern of an inductive ruler, and further analyzing a position of the stimulated magnetic component by a technical means of voltage resolution for positions.

Description

Magnetic position sensing device and method

This case is about position sensing technology, especially a magnetic position sensing device and method.

High-precision position detection components include optical scales and magnetic scales, etc., which are widely used in the precision machinery industry (such as machine tools) and smart manufacturing industries (such as precision mechanical arms), etc., where processing equipment often requires product processing in harsh environments Compared with the optical ruler, the magnetic ruler has better anti-pollution ability and simple structure. In recent years, the research and development of high-end magnetic ruler has become more and more active, and it has gradually replaced the market of middle-order optical ruler.

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

Therefore, how to effectively improve the magnetization time-consuming, the installation accuracy is difficult to control, and the production length is limited, etc., is really one of the issues that the industry urgently needs to solve.

In order to overcome the deficiency of the conventional technology, this case provides a magnetic position sensing device, which includes: an exciting element, which generates an alternating magnetic field; and an inductive ruler, a pattern is formed, and the relative position of the pattern and the exciting element changes To generate an induced voltage, the pattern is a periodic waveform pattern; and a position analysis element to capture the induced voltage, the position analysis element is connected to the sensing ruler to resolve the excitation element on the sensing ruler based on the induced voltage s position.

This case also provides a magnetic position sensing method, which includes: forming a pattern on a sensing ruler; causing an exciting element to generate an alternating magnetic field; using the relative position change of the pattern of the sensing ruler and the exciting element to generate an induced voltage, the pattern is A periodic waveform pattern; and using a position analyzing element to capture the induced voltage, the position analyzing element is connected to the sensing ruler, and the position of the excitation element on the sensing ruler is resolved based on the sensing voltage.

It can be seen from the above that the present case uses the relative position change of the pattern of the sensing ruler and the exciting element to generate an induced voltage, and then uses the voltage value to analyze the position to improve the position detection accuracy and stability, and the metal wire pattern transfer process is easy Advantages such as scale up can solve the problems of time-consuming magnetization, difficult installation accuracy control, and limited production length encountered in the prior art using magnetic pole pattern sensing and voltage phase difference analysis.

1: magnetic position sensing device

10: Excitation element

20: Induction ruler

21: Positive

22: reverse side

30,30’: pattern

31: Square wave graphics

31’: the first graphic

32: Second graphic

40: Position resolution element

41: Induced voltage signal processing unit

42: Inductive voltage analysis position unit

61: square wave area

62: negative square wave area

63: alternating magnetic field

101: Magnetic Conduction Department

102: Winding Department

103: AC power supply unit

104: first magnetic pole

105: second magnetic pole

106: opening

311: Processing voltage

311’: First processing voltage

313,313’: Level 1 of the first peak and valley

314,314’: the first vertical section

315,315’: horizontal part of the first peak

321: Second processing voltage

323: Second Peak Valley Level

324: Second vertical section

325: second peak level

411: filter

412: Envelope detector

511: The first non-turning curve section

512: first turning curve section

513: The first ascending line segment

514: first descending line

515: First Mountain Area

516: the first trough area

521: Second non-turning curve section

522: Second turning curve section

523: Second rising line

524: Second descending line

525: Second Mountain Area

526: Second trough area

B: Crest turning zone

X: distance

V _S , V _S1 , V _S2 : induced voltage

V _P , V _P1 , V _P2 : processing voltage

S71~S74, S81~S82: Steps

Fig. 1 is a schematic diagram of the first embodiment of the magnetic position sensing device of the present case; Fig. 2 is a schematic diagram of the exciting element of the first embodiment of the magnetic position sensing device of the present case; Fig. 3 is a diagram of the magnetic position sensing device of the present case A schematic diagram of the position resolution element of the first embodiment; Figure 4 is a schematic diagram of the induced voltage signal processing unit of the first embodiment of the magnetic position sensing device of this case; Figure 5A is a schematic diagram of the pattern of the sensing ruler of the first embodiment of the magnetic position sensing device of this case; FIG. 5C is a schematic diagram of signal processing of the induced voltage of the first embodiment of the magnetic position sensing device of this case; FIG. 5D is a schematic diagram of the magnetic position sensing map of the first embodiment of the magnetic position sensing device of this case; FIG. 5E is A schematic diagram of the relationship between the square wave pattern and the processing voltage of the first embodiment of the magnetic position sensing device of this case; FIG. 5F is an enlarged schematic diagram of the turning point of the processing voltage of the first embodiment of the magnetic position sensing device of this case; 6A The figure is a schematic diagram of the pattern of the induction ruler of the second embodiment of the magnetic position sensing device of this case; FIG. 6B is a diagram of the magnetic position sensing diagram of the second embodiment of the magnetic position sensing device of this case; FIG. 6C is the diagram of this case A schematic diagram of the analysis section of the second embodiment of the magnetic position sensing device; FIG. 7 is a schematic flowchart of the first embodiment of the magnetic position sensing method of this case; and FIG. 8 is a first implementation of the magnetic position sensing method of this case An example flow chart of step S74.

The following describes the implementation of this case by specific specific embodiments, and those skilled in the art can easily understand other advantages and effects of this case by the contents disclosed in this specification.

It should be noted that the structure, ratio, size, etc. shown in the drawings of this specification are only used to match the contents disclosed in the specification, for those familiar with this skill to understand and read, not to limit the implementation of this case. Limited conditions, so it has no technical significance, any modification of structure, change of proportional relationship or adjustment of size should still fall within the disclosure of this case without affecting the efficacy and purpose of this case. The technical content can be covered. At the same time, the terms such as "first" and "second" cited in this specification are only for the convenience of description, not to limit the scope of this case, the change or adjustment of the relative relationship. Without substantial changes in technical content, it should be regarded as the scope of this case.

FIG. 1 is a schematic diagram of the first embodiment of the magnetic position sensing device 1 of this case. As shown in the figure, the magnetic position sensing device 1 includes an excitation element 10 to which an alternating current power is applied to generate an alternating magnetic field; the induction scale 20 is formed with a pattern 30 and the relative position of the pattern 30 and the excitation element 10 changes The induced voltage; and the position analyzing element 40 are connected to the sensing scale 20 to read the induced voltage generated by the sensing scale 20 and analyze the position of the excitation element 10 on the sensing scale 20 according to the induced voltage.

In one embodiment, the pattern 30 of the sensor scale 20 is composed of metal wires.

In one embodiment, the pattern 30 of the sensing ruler 20 is a periodic waveform pattern, and both ends of the periodic waveform pattern are connected to the position analysis element 40 for the position analysis element 40 to read the pattern 30 and the excitation element The induced voltage caused by the relative position change of 10.

FIG. 2 is a side view of the excitation element 10 of the first embodiment of this case. As shown in the figure, the exciting 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 permeable portion 101 has a ring shape 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 permeable portion 101, and the opening 106 is located between the first magnetic pole portion 104 and the second magnetic pole portion 105 At the same time, the winding part 102 has a coil structure and is wound on the magnetic conductive part 101. At the same time, the excitation element 10 moves through the opening 106 on the pattern 30 of the induction scale 20, or the excitation element 10 is fixed to move the induction scale 20 in the opening 106.

The alternating-current power supply unit 103 applies alternating-current power to the winding part 102 to generate the alternating magnetic field, so that the relative position of the pattern 30 of the induction scale 20 and the exciting element 10 changes to generate the induced voltage.

FIG. 3 is a schematic diagram of the position analyzing element 40 of the magnetic position sensing device 1 of this case. As shown in the figure, the position analysis element 40 includes an induced voltage signal processing unit 41 connected to the pattern 30 on the sensing scale 20 to read the induced voltage V _S generated by the relative position change of the pattern 30 and the excitation element 10, And filtering and detecting signal processing of the induced voltage V _S to obtain the processed voltage V _P ; and the induced voltage analysis position unit 42 is connected to the induced voltage signal processing unit 41 to receive the processed voltage V _P according to The period of the processing voltage V _P corresponds to the relationship that the length on the X coordinate is equal to the period of the pattern 30 on the sensing scale 20 corresponds to the distance on the X coordinate, so as to analyze the position of the exciting 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 in this case. As shown, the induced voltage signal processing unit 41 includes a filter system 411, the system for filtering the induced voltage V _S, the carrier frequency of the induced AC voltage V _S is filtered; and the envelope detector (Envelope A detector 412 is connected to a filter 411 to detect the induced voltage V _S with the carrier frequency filtered to obtain the processing voltage V _P.

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 (not shown), the output of the first amplifier is connected to the input of the filter 411, and the input of the first amplifier It is connected to the pattern 30 of the sensor scale 20 to obtain the induced voltage generated by the change in the relative position of the pattern 30 and the exciting element 10 from the sensor scale 20, and amplify the induced voltage to output it to the filter 411, but not This is limited.

In this embodiment, the induced voltage signal processing unit 41 further includes: a level shifter (not shown), which is connected to the envelope detector 412, and processes the processed voltage V for the signal processing of filtering and detection _P performs level shift processing to obtain the level required by the processing voltage V _P for subsequent work (referred to herein as the voltage level); and a second amplifier (not shown), which deviates from the level shifter are connected so as to complete the processing of the level-shift processing to the amplified output voltage V _P of the induced voltage position parsing unit 42, but is not limited thereto.

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 resolution position unit 42 to convert the induced voltage the signal processing unit 41 processing the resulting voltage V _P is converted into the digital signal processing the voltage V _P to the induction voltage, and transmits the position parsing unit 42, but is not limited thereto.

FIG. 5A is a schematic diagram of the first embodiment of the pattern 30 of the sensor ruler 20 in this case. As shown in the figure, the pattern 30 of the first embodiment is a square wave pattern 31 and is formed only on one side of the front surface 21 or the reverse surface 22 opposite to the front surface 21 of the sensing ruler 20 shown in FIG. It consists of a complex first peak-valley horizontal portion 313, a complex first vertical portion 314, and a complex first peak-top horizontal portion 315, and the line width of the square wave pattern 31 is 1 mm. The line distance (A) is 4 mm, and the period (T _D ) of the square wave pattern 31 corresponds to the distance on the X coordinate of 8 mm, 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 is a negative square wave area 62.

FIG. 5B is a schematic waveform diagram of the induced voltage of the first embodiment caused by the relative position change of the pattern 30 and the excitation element 10 of the position analysis element 40 of the present invention. As shown in the figure, after the excitation element 10 moves a distance ΔX on the induction ruler 20, the relative position of the pattern 30 on the induction ruler 20 and the excitation element 10 changes to produce a corresponding change in the induced voltage (the amplitude of the waveform changes) . Therefore, the relationship between the induced voltage V _S1 and the induced voltage V _{S2 is} the relationship of the exciter element 10 moving distance ΔX on the induction scale 20, and because the induced voltage includes the amplitude of the carrier frequency of the AC power source 103, the induced voltage V _S1 moves Amplitude changes from the distance ΔX to the induced voltage V _S2 .

FIG. 5C is a schematic diagram of the processed 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 due to the processed voltage It corresponds to the induced voltage, so the change ΔV relationship between the processing voltage V _P1 and the processing voltage V _P2 is also the change of the ΔX distance.

After the exciting element 10 generates the alternating magnetic field, the induced voltage signal processing unit 41 performs filtering and detection signal processing on the induced voltage V _S generated by the relative position change of each pattern 30 and the exciting element 10 to obtain After the processing voltage 311 in the form of a triangular wave shown in FIG. 5D, the induced voltage analysis position unit 42 extracts all sections of the processing voltage 311 in the form of a triangular wave shown in FIG. 5D as analysis sections, and analyzes The period of the processing voltage of the section (T _L ) corresponds to the length on the X coordinate, and the period (T _D ) of the square wave pattern 31 corresponds to the distance unit on the X coordinate, and then the processing voltage of the analysis section follows The change of the distance unit is the moving distance of the exciting element 10 on the induction scale 20, and the position of the excitation element 10 on the induction scale 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 change in the induced voltage V _S1 is relative to the distance that the exciting element 10 moves on the pattern 30, the period of the processing voltage shown in FIG. 5D ( T _L ) The length corresponding to the X coordinate is expressed in terms of the period of the pattern 30 (T _D ) 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 scale 20, S is the number of cycles of the analysis section (0, 0.5, 1, 1.5, ...), and T _L is the period of the analysis section , X ₀ is the distance from the processing voltage in the Sth period to X, V _t is the processing voltage value, V ₀ is the linear starting voltage value in the Sth period, 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 scale 20 and the processing voltage 311 in the first embodiment of the present invention. As shown in the figure, the relative position of the square wave pattern 31 and the exciting element 10 changes to produce a processing voltage 311 corresponding to a triangular-like waveform. FIG. 5F shows a processing voltage 311 of a triangular-like waveform at the peak-to-valley transition area (as shown in the 5E The peak transition zone B) shown in the figure is arc-like.

FIG. 6A is a schematic diagram of the pattern 30 ′ of the second embodiment of the magnetic position sensing device 1 of this case. As shown in the figure, the difference between this embodiment and the first embodiment lies in the pattern 30', so the differences will be described below, and the similarities will not be repeated. The pattern 30' in 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 scale 20 shown in FIG. 1, and the second pattern 32 is formed on the first 1 shows the opposite side 22 of the sensor scale 20, wherein the first pattern 31' and the second pattern 32 are located on the same horizontal line, and the first pattern 31' and the second pattern 32 are the same and are different from each other by 1/ 2 line spacing (A) or 1/4 period (T _D ), wherein the first pattern 31' is composed of a plurality of first peak and valley horizontal parts 313', a plurality of first vertical parts 314' and a plurality of first peak top horizontal parts A square wave pattern composed of 315', the second pattern 32 is a square wave pattern composed of 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 relative position of the first pattern 31' and the exciting element 10 of the second embodiment changes to generate a first induced voltage and the relative position of the second pattern 32 and the exciting element 10 changes to generate a second induced voltage, each of the induced voltages The induced voltage signal processing unit 41 processes two triangular wave-like processing voltages located on the same horizontal line and different from each other by 1/4 cycle as shown in FIG. 6B. The first processing voltage 311' corresponds to the first pattern 31' The second processing voltage 321 corresponds to the second pattern 32, and the first processing voltage 311' and the second processing voltage 321 both exhibit a triangular wave-like waveform. As shown in FIG. 6A, the first pattern 31' and the second pattern 32 are mutually The phase difference is 1/2 line spacing (A) or 1/4 cycle (T _D ). Therefore, the first processing voltage 311 ′ and the second processing voltage 321 also differ from each other by 1/4 cycle (T _D ).

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-inverted portions, so the slope approaches a fixed value, and the first processing voltage 311 The waveforms of the first turning curve section 512 and the second turning curve section 522 of the second processing voltage 321 are inversion parts, so the slope cannot be approached to a fixed 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, and the second non-inflection curve segment 521 includes a second ascending line segment 523 and a second descending line segment 524, the first inflection curve segment 512 includes a first mountain region 515 and a first trough region 516, and a second turning curve section 522 includes a second mountain region 525 and a second trough region 526.

Next, the induced voltage analysis position unit 42 subtracts the first peak area 515 and the first trough area 516 of the first processing voltage 311 ′ to extract only the first rising line segment 513 and the first falling line segment 514. Similarly, the induced voltage analysis The position unit 42 subtracts the second peak region 525 and the second trough 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 segment in FIG. 6B), so that All the rising and falling line segments of the first processing voltage 311 and the second processing voltage 321 form the analysis section of the forward and reverse interleaved triangle wave as shown in FIG. 6C, and the period (T _L ) of the processing voltage of the analysis section Corresponding to the length on the X coordinate, the period (T _D ) of the first graph 31 ′ or the second graph 32 corresponds to the distance unit on the X coordinate, so that the processing voltage of the analysis section changes with the distance unit It is the moving distance of the excitation element 10 on the induction scale 20 to complete the position sensing waveform shown in FIG. 6C, and then the position of the excitation element 10 on the induction scale 20 is analyzed from the analysis section .

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 length to coordinate system X 'or the period (T _D) of the first pattern 31 corresponding to the second pattern 32 on the X-coordinate distance units.

T_D或

A)時，從第一處理電壓311’與第二處理電壓321之非轉折曲線區段的分析區段中，可取得激磁元件10之位置感知的最佳往覆精度誤差範圍及定位精度，其最佳往覆精度誤差範圍為±0.003mm及最佳定位精度為0.01mm。 Since the induced voltage analysis position unit 42 only captures non-inflection curve sections 511 and 521 whose slope approaches a fixed value, the pattern 30' of the second embodiment is more effective than the pattern 30 of the first embodiment excitation element 10 to improve the position accuracy of perception, wherein, in the second embodiment, back to Figure 6A, when the first pattern 31 'and the second pattern period (T _D) 32 corresponding to the coordinates X The distance 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 misaligned by 2mm (

T _D or

A), from the analysis section of the non-inflection curve section of the first processing voltage 311' and the second processing voltage 321, the optimal repeating accuracy error range and positioning accuracy of the position sensing of the excitation element 10 can be obtained. The error range of the best repeat accuracy is ±0.003mm and the best positioning accuracy is 0.01mm.

As shown in FIG. 6C in the second embodiment, the induced voltage analysis position unit 42 further includes a position conversion algorithm to directly swap out the position (X) of the exciting element 10 on the induction scale 20, where X=S×1 /2(T _L )+X ₀ =S×1/2(T _L )+(V _t -V ₀ )/m, where X is the position of the excitation element 10 on the induction scale 20, and S is the analysis section The number of cycles (0, 0.5, 1, 1.5, ...), T _L is the distance of the cycle of the analysis section, X ₀ is the distance from the processing voltage of the Sth cycle to X, V _t is the processing voltage value, V ₀ It is the linear starting voltage value of the Sth period, 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 T _{L are} calculated, we can know S×1/2(T _L ), the slope value m is known from the rising and falling sections of the triangular wave, and the linear starting voltage value V _{0 in} the S period is known After measuring the processing voltage value V _t , the distance X _{0 of the} induced voltage from the Sth period to X can be calculated, whereby the position X of the excitation element 10 on the induction scale 20 can be obtained.

FIG. 7 is a schematic flowchart of the first embodiment of the magnetic position sensing method of the present case (that is, the single-sided pattern ruler in FIG. 5A). As shown in the figure, it includes the following steps: in step S71, a pattern 30 is formed on a sensing ruler 20; in step S72, an exciting element 10 is generated to generate an alternating magnetic field; in step S73, the sensing ruler 20 is used The relative position of the pattern 30 and the excitation element 10 changes to generate an induced voltage; and in step S74, a position analysis element 40 is used to capture the induced voltage, and the excitation element 10 is located on the induction scale 20 according to the induced voltage s position.

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 flowchart of the step S74. As shown in the figure, it includes the following steps: In step S81, an induced voltage signal processing unit 41 reads the induced voltage V _S generated by the relative position change of the pattern 30 and the exciting element 10 to the sensing scale 20, and Filtering and detecting the signal of the induced voltage V _S to obtain the processed voltage V _P ; and in step S82, causing an induced voltage analysis position unit 42 to read the processed voltage V _P according to the period of the processed voltage The length on the X coordinate is equal to the relationship between the period of the pattern 30 on the sensing scale 20 and the distance on the X coordinate, so as to resolve the position of the exciting element 10 on the sensing scale 20 from the processing voltage.

In this embodiment, the step S81 includes: filtering the induced voltage with a low-pass filter (that is, the filter 411 in FIG. 4), so that the carrier frequency of the AC power supply in the induced voltage V _S Filter out; use the envelope detector (that is, the envelope detector 412 in FIG. 4) to detect the induced voltage V _S at which the carrier frequency is filtered to obtain the processing voltage V _P.

In the first embodiment, the step S71 is to form the pattern 30 of the square wave pattern 31 on one of the front surface 21 of the sensing scale 20 or the opposite surface 22 opposite to the front surface 21; the induced voltage signal in the step S81 is processed The unit 41 reads the induced voltage generated by the change in the relative position of the square wave pattern 31 and the exciting element 10 from the sensing ruler 20, and performs signal processing of filtering and detecting the induced voltage V _S to obtain the processing in the form of a triangular wave Voltage 311; and the induced voltage analysis position unit 42 in step S82 reads the processing voltage 311 of the triangular wave-like processing, and makes all sections of the processing voltage 311 of the triangular wave-like processing as analysis sections, and according to the processing The period of the voltage corresponds to the relationship that the length on the X coordinate is equal to the period of the square wave pattern 31 on the induction scale 20 corresponds to the distance on the X coordinate, and the period (T _L ) of the processing voltage of the analysis section corresponds to the X coordinate The upper length is expressed by the distance unit on the X coordinate corresponding to the period (T _D ) of the square wave pattern 31 to complete the position-aware waveform shown in FIG. 5D, and the processing voltage of the analysis section varies with the distance unit The change of is the moving distance of the exciting element 10 on the induction scale 20, and the position of the excitation element 10 on the induction scale 20 is analyzed from the analysis section.

This case 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 first embodiment described above is the pattern 30′, so the following will describe the differences, and The details are not repeated. In this step S71, the front surface 21 and the back surface 22 of the sensor scale 20 are respectively formed with patterns on the same horizontal line, and each of the patterns is a first pattern 31' and a second pattern 32 of a square wave pattern, which are different from each other by 1/2 Line pitch or 1/4 cycle (as shown in FIG. 6A); causing the induced voltage signal processing unit 41 in step S81 to perform the signal processing on the induced voltage generated by the relative position change of each pattern and the excitation element 10 To obtain the two triangular wave-like processing voltages (ie, the first processing voltage 311' and the second processing voltage 321) that are located on the same horizontal line and differ from each other by 1/4 cycle; and the induced voltage in the step S82 is resolved The unit 42 reads the two triangular-wave-like processing voltages (ie, the first processing voltage 311' and the second processing voltage 321), and extracts the two triangular-wave-like processing voltages (ie, the first processing voltage 311' and The second processing voltage 321) of the non-turning curve section (that is, the first non-turning curve section 511 and the second non-turning curve section 521) to obtain the analysis section of the forward and reverse interleaved triangle wave (as shown in FIG. 6C) ), and based on the relationship between the period of the processing voltage corresponding to the length on the X coordinate equal to the first pattern 31' or the second pattern 32 on the sensor scale 20 corresponding to the distance on the X coordinate, the analysis section The period of the processing voltage (T _L ) corresponding to the length on the X coordinate is expressed in terms of the distance unit on the X coordinate corresponding to the period of the first pattern 31 ′ or the second pattern 32 (T _D ) to complete as shown in FIG. 6C The position-aware waveform graph, and 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 scale 20, and then the excitation element 10 is located in the induction scale 20 from the analysis section On the location.

In the first embodiment of the method (that is, the single-sided pattern ruler in FIG. 5A), the step S82 further includes providing a replacement arithmetic algorithm to directly swap out the excitation element 10 on the induction ruler 20 from the position-aware waveform diagram position (X), _{wherein, X = S × T L +} X 0 = S × T L + (V t -V 0) / m, where, X is the excitation element 10 in position on the foot sensor 20, S is The number of cycles of the analysis section (0, 0.5, 1, 1.5, ...), T _L is the distance of the period of the analysis section, X ₀ is the distance from the processing voltage of the Sth cycle to X, and V _t is the value of the processing voltage , V ₀ is the linear starting voltage value of the Sth period, m is the slope value of (X, 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), step S82 further includes providing a one-bit replacement algorithm to directly replace the excitation element 10 on the induction ruler 20 from the position-aware waveform diagram. Position (X), where X=S×1/2(T _L )+X ₀ =S×1/2(T _L )+(V _t -V ₀ )/m, where X is the excitation element 10 in For the position on the sensor scale 20, S is the number of periods of the analysis section (0, 0.5, 1, 1.5, ...), T _L is the distance of the period of the analysis section, X ₀ is S × 1/2 (T _L ) The distance from the point X, V _t is the processing voltage value, V ₀ is the linear starting voltage value of the Sth period, m is the slope value of (X, V _t ), and there are many position conversion algorithms. limit.

This case is known from the above. In this case, the induced voltage is generated by the relative position change of the pattern of the sensing ruler and the exciting element 10, and then the technical means of analyzing the position by voltage value is used to improve the position detection accuracy and stability, and the transfer of the metal wire pattern The process is easy to scale up and other advantages, to solve the problems of time-consuming magnetization, difficult installation accuracy control, and limited production length encountered in the prior art using magnetic pole pattern sensing and voltage phase difference analysis.

1: magnetic position sensing device

10: Excitation element

20: Induction ruler

21: Positive

22: reverse side

30: pattern

31: Square wave graphics

40: Position resolution element

Claims (14)

A magnetic position sensing device includes: an exciting element for generating an alternating magnetic field; an inductive ruler formed with a pattern, and the relative position of the pattern and the exciting element changes to generate an induced voltage, and the pattern is a period A waveform pattern; and a position resolution element that captures the induced voltage. The position resolution element is connected to the sensing ruler to resolve the position of the excitation element on the sensing ruler based on the induced voltage. The magnetic position sensing device as described in item 1 of the patent application range, wherein the pattern of the sensor scale is composed of metal wires. The magnetic position sensing device described in item 1 of the scope of the patent application further includes: an AC power supply unit that applies AC power to the excitation element to generate the alternating magnetic field. According to the magnetic position sensing device described in item 3 of the patent application range, the position analysis element further includes: an induced voltage signal processing unit, which reads the induced voltage and sequentially performs signal processing for filtering and detecting the induced voltage, To obtain the processing voltage, wherein the filtering is to filter out the carrier frequency of the AC power contained in the induced voltage; and the induced voltage resolution position unit is based on the period of the processing voltage corresponding to the length on the X coordinate equal to the induction The period of the pattern on the ruler corresponds to the relationship of the distance on the X coordinate to resolve the position of the excitation element on the sensing ruler. The magnetic position sensing device as described in item 4 of the patent application range, wherein the pattern on the sensor scale is a square wave pattern and is located on the front or back surface of the sensor scale, so that the induced voltage signal processing unit responds to the pattern Communicate with the induced voltage generated by the relative position change of the excitation element Signal processing to obtain the processing voltage in the form of a triangular wave, and the induced voltage analysis position unit extracts all sections of the processing voltage in the form of a triangular wave to obtain an analysis section, and corresponds to the X coordinate according to the period of the processing voltage The length is equal to the relationship between the period of the pattern on the sensor scale and the distance on the X coordinate, and the position of the excitation element on the sensor scale is resolved from the analysis section. The magnetic position sensing device as described in item 4 of the patent application scope, wherein the front and back sides of the sensor scale each have a pattern on the same horizontal line, each of which is a square wave pattern and differs from each other by 1/2 line distance or 1/4 cycle, so that the induced voltage signal processing unit performs signal processing on the induced voltage generated by the relative position change of each of the pattern and the exciting element, so as to obtain two located on the same horizontal line and different from each other by 1/4 cycle The processing voltage in the form of a triangle wave, and the induced voltage analysis position unit extracts the two non-inflection curve sections of the processing voltage in the form of a triangle wave to obtain the analysis section of the forward and reverse interleaved triangular wave, and according to the processing voltage The period corresponds to the relationship that the length on the X coordinate is equal to the length of the pattern on the sensor scale corresponds to the distance on the X coordinate, and the position of the excitation element on the sensor scale is resolved from the analysis section. The magnetic position sensing device as described in item 4 of the patent application scope, wherein the induced voltage signal processing unit obtains the processed voltage without the carrier frequency after filtering and detecting signal processing of the induced voltage with amplitude variation, The voltage change of the processing voltage corresponds to the change of the moving distance of the exciting element on the induction scale. The magnetic position sensing device as described in item 1 of the patent application scope, wherein the excitation element further includes 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, so that the The excitation element moves the pattern on the induction scale through the first magnetic pole part and the second magnetic pole part in the opening. A magnetic position sensing method, including: Forming a pattern on an inductive ruler; causing an exciting element to generate an alternating magnetic field; using a change in the relative position of the inductive ruler pattern and the exciting element to generate an induced voltage, the pattern is a periodic waveform pattern; and using a position analysis element Extracting the induced voltage, the position analysis element is connected to the induction scale, and the position of the excitation element on the induction scale is resolved according to the induction voltage. The magnetic position sensing method as described in item 9 of the patent application scope, wherein the alternating magnetic field is generated by an alternating current power supply unit applying alternating current power to the exciting element. The magnetic position sensing method as described in item 10 of the patent application range, wherein the step of the position analyzing element resolving the position of the excitation element on the induction scale includes: causing an induced voltage signal processing unit to sense The ruler reads the induced voltage generated by the relative position change of the pattern and the exciting element, and then performs filtering and detection signal processing on the induced voltage in sequence to obtain a processed voltage, wherein the filtering is to convert the induced voltage The carrier frequency of the included AC power supply is filtered out; and the relationship between the length of the induced voltage analysis position unit corresponding to the period of the processing voltage on the X coordinate is equal to the period of the pattern on the induction scale corresponding to the distance on the X coordinate To resolve the position of the excitation element on the induction scale from the processing voltage. The magnetic position sensing method as described in item 11 of the patent application scope, wherein a square wave pattern is formed on the front or back surface of the sensor scale, so that the induced voltage signal processing unit has the relative position of the pattern and the exciting element The induced voltage generated by the change is subjected to signal processing to obtain the processed voltage in the form of a triangle wave, and the induced voltage analysis position unit is to extract all sections of the processed voltage in the form of a triangle wave to obtain an analysis section and based on the processing The period of the voltage corresponds to the X coordinate The length is equal to the relationship between the period of the pattern on the sensor scale and the distance on the X coordinate, and the position of the excitation element on the sensor scale is resolved from the analysis section. The magnetic position sensing method as described in item 11 of the patent application scope, wherein the front and back surfaces of the sensor scale are each formed with patterns on the same horizontal line, each of which is a square wave pattern and differs from each other by 1/2 line Distance or 1/4 cycle, so that the induced voltage signal processing unit performs signal processing on the induced voltage generated by the relative position change of each of the pattern and the excitation element to obtain the same horizontal line and the difference of 1/4 cycle from each other Two triangular voltage-like processing voltages, and the induced voltage analysis position unit is used to extract the two non-inflection curve sections of the triangular voltage-like processing voltages to obtain the forward and reverse interleaved triangular wave analysis sections, and according to the processing The period of the voltage corresponding to the length on the X coordinate is equal to the relationship between the period of the pattern on the sensing scale and the distance on the X coordinate, and the position of the exciting element on the sensing scale is analyzed from the analysis section. The magnetic position sensing method as described in item 11 of the patent application range, wherein the induced voltage signal processing unit filters and detects the induced voltage with amplitude change to obtain the signal without the carrier frequency Processing voltage, the voltage change of the processing voltage corresponds to the change of the moving distance of the excitation element on the induction scale.

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