JPS6239683B2 - - Google Patents
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- Publication number
- JPS6239683B2 JPS6239683B2 JP4431480A JP4431480A JPS6239683B2 JP S6239683 B2 JPS6239683 B2 JP S6239683B2 JP 4431480 A JP4431480 A JP 4431480A JP 4431480 A JP4431480 A JP 4431480A JP S6239683 B2 JPS6239683 B2 JP S6239683B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- storage medium
- magnetic field
- signal
- magnetic storage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000005291 magnetic effect Effects 0.000 claims description 68
- 230000005415 magnetization Effects 0.000 claims description 15
- 238000005259 measurement Methods 0.000 claims description 10
- 230000005294 ferromagnetic effect Effects 0.000 claims description 4
- 239000000696 magnetic material Substances 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 7
- 239000006185 dispersion Substances 0.000 description 7
- 230000000737 periodic effect Effects 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910020630 Co Ni Inorganic materials 0.000 description 1
- 229910002440 Co–Ni Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 230000002902 bimodal effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003302 ferromagnetic material Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Landscapes
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
Description
【発明の詳細な説明】
本発明は、測長方向に沿つて磁気記憶媒体に等
間隔のビツト長Ｐを有する磁化の繰り返しの形で
記録されている磁気信号を、強磁性磁気抵抗効果
素子（以下MR素子と略称する）より成る磁気セ
ンサーで読み取ることにより測長を行う測長器に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic signal recorded in a magnetic storage medium in the form of repeating magnetization with equally spaced bit lengths P along the length measurement direction, using a ferromagnetic magnetoresistive element ( This invention relates to a length measuring device that measures length by reading with a magnetic sensor consisting of a magnetic sensor (hereinafter abbreviated as MR element).
従来、この種の測長器の磁気センサーは、前記
ビツト長Ｐに対応した所定の間隔（例えば1/4
Ｐ）毎に、平らな基板上に平行に形成された、複
数個の短冊状MR素子から成り、これが前記磁気
記憶媒体から発する信号磁界の前記基板に平行な
成分（以下これを、水平成分と言う）を検知でき
る様に、前記磁気記憶媒体面に対して、所定のス
ペーシングを隔てて、平行に設定されており、前
記磁気記憶媒体とMRセンサーとの相対移動距離
及び移動方向は、磁気信号による個々のMR素子
の抵抗変化を再生回路で処理することにより検出
されていた。 Conventionally, the magnetic sensor of this type of length measuring device has a predetermined interval (for example, 1/4) corresponding to the bit length P.
P) consists of a plurality of strip-shaped MR elements formed in parallel on a flat substrate, and this is used to detect the component (hereinafter referred to as the horizontal component) of the signal magnetic field emitted from the magnetic storage medium parallel to the substrate. The MR sensor is set parallel to the surface of the magnetic storage medium with a predetermined spacing therebetween so as to be able to detect the MR sensor. It was detected by processing the resistance change of each MR element due to the signal using a reproducing circuit.
ここで、第１図に示すように、短冊状MR素子
１の幅方向磁界Hxと比抵抗ρとの関係は、通
常、異方性分散のため２つの曲線２，３から成る
双峰状の曲線となる。そして、信号磁界によつ
て、どちらの曲線に従つた抵抗変化をするかは、
MR素子の履歴によつて、まちまちである。 Here, as shown in FIG. 1, the relationship between the width direction magnetic field Hx of the strip-shaped MR element 1 and the specific resistance ρ is usually a bimodal shape consisting of two curves 2 and 3 due to anisotropic dispersion. It becomes a curve. Which curve should the resistance change follow depending on the signal magnetic field?
It varies depending on the history of the MR element.
例えば、曲線２に従つた場合は、磁気記憶媒体
からの周期的信号磁界４に対してMR素子の抵抗
変化は、５に示す様な１つおきの歪んだ波形とな
るので、磁気センサーの信号出力と、信号磁界４
との対応関係が悪くなる。その結果、正しい測長
が困難になる。曲線３に従つた場合も同様であ
る。さらに、この傾向は磁気記憶媒体とMR素子
との間隔即ちスペーシングが大きくなつて、MR
素子に加わる信号磁界強度が小さくなるにつれて
顕著となるので、スペーシングは、あまり大きく
はできない。このことは、測長器を組み立てる際
に、高い精度が必要であること、すなわち、測長
器がコスト高になることを意味する。 For example, when curve 2 is followed, the resistance change of the MR element in response to the periodic signal magnetic field 4 from the magnetic storage medium becomes a distorted waveform every other wave as shown in 5, so the magnetic sensor signal Output and signal magnetic field 4
Correspondence with the relationship deteriorates. As a result, correct length measurement becomes difficult. The same applies to the case where curve 3 is followed. Furthermore, this trend is exacerbated by the increase in the spacing between the magnetic storage medium and the MR element.
The spacing cannot be made too large because it becomes more noticeable as the signal magnetic field strength applied to the element becomes smaller. This means that high precision is required when assembling the length measuring device, which means that the cost of the length measuring device is high.
一方、上述の又峰曲線２，３は、MR素子の長
手方向に弱い直流バイアス磁界を加えると、分散
が小さくなるので、同図６に示す様に、修正でき
ることがよく知られている。その結果、MR素子
の抵抗変化の歪も修正され、７に示す様に信号磁
界４に対応した、良好なものとなる。 On the other hand, it is well known that the above-mentioned curves 2 and 3 can be corrected as shown in FIG. 6 because the dispersion becomes smaller when a weak DC bias magnetic field is applied in the longitudinal direction of the MR element. As a result, the distortion caused by the resistance change of the MR element is also corrected, and as shown in 7, it becomes suitable for the signal magnetic field 4.
本発明の目的は、この様な直流バイアス磁界を
容易な手段で設けることによつて、上記欠点を解
決し、低価格で、信頼性の高い測長器を提供する
ことにある。 An object of the present invention is to solve the above-mentioned drawbacks by providing such a DC bias magnetic field by a simple means, and to provide a low-cost and highly reliable length measuring device.
本発明の構成は、一面には磁気信号を測長方向
に沿つて磁化の繰り返しの形で記録している磁気
記憶媒体が形成されており、他の面には測長区間
にわたつて所定の幅で測長方向と直角方向に着磁
された磁気記憶媒体が形成されているスケール
と、該スケールに平行に配置され該スケールとの
相対運動に伴つて前記２つの磁気記憶媒体から生
じる磁界の変化を電録抵抗の変化として感知する
MR素子より成る磁気センサーとから測長部を構
成することを特徴とする。 In the structure of the present invention, a magnetic storage medium is formed on one surface in which a magnetic signal is recorded in the form of repeated magnetization along the length measurement direction, and a predetermined signal is recorded on the other surface over the length measurement section. A scale on which a magnetic storage medium is magnetized in a direction perpendicular to the length measurement direction in width, and a magnetic field generated from the two magnetic storage media that is arranged parallel to the scale and moves relative to the scale. Detect changes as changes in electrographic resistance
It is characterized in that the length measuring section is constituted by a magnetic sensor consisting of an MR element.
次に本発明の実施例において図面を参照して説
明する。 Next, embodiments of the present invention will be described with reference to the drawings.
第２図は、本発明の一実施例を示したものであ
る。ａに示すように略、直方体形状をした、スケ
ールブロツク８の片面には、磁気信号が測長方向
（ｘ方向）に沿つて等間隔のビツト長Ｐを有する
磁化１０の繰り返しの形で記録されている磁気記
憶媒体９が形成されており、その裏側には、同図
ｂに示す様に、測長区間にわたつて所定の幅Ｌで
ｙ方向に着磁された磁気記憶媒体１１が形成され
ている。そして、前記磁気記憶媒体９から発する
信号磁界を検出する様に磁気センサー１３が配設
される。 FIG. 2 shows an embodiment of the present invention. As shown in a, a magnetic signal is recorded on one side of the scale block 8, which has a substantially rectangular parallelepiped shape, in the form of repeated magnetizations 10 having bit lengths P at equal intervals along the length measurement direction (x direction). A magnetic storage medium 9 is formed, and on the back side thereof, as shown in FIG. ing. A magnetic sensor 13 is arranged to detect a signal magnetic field emitted from the magnetic storage medium 9.
ここで本発明の動作を解り易くするために、磁
気センサー１３として、平らな基板上に４つの短
冊状のMR素子が1/4Ｐのピツチで形成されたも
のを例にして第３図乃至第５図を用いて説明す
る。 Here, in order to make the operation of the present invention easier to understand, an example in which four strip-shaped MR elements are formed on a flat substrate with a pitch of 1/4P is used as the magnetic sensor 13, and FIGS. This will be explained using Figure 5.
第３図はMR素子１６〜１９と、前記磁気記憶
媒体９，１１との位置関係を示したものであり、
４つの短冊状MR素子１６〜１９が、磁気記憶媒
体９に対して、信号磁界１４の水平成分を検出す
る様に、スペーシングＤを介して平行に配設され
ている。 FIG. 3 shows the positional relationship between the MR elements 16 to 19 and the magnetic storage media 9 and 11,
Four strip-shaped MR elements 16 to 19 are arranged parallel to the magnetic storage medium 9 with a spacing D in between so as to detect the horizontal component of the signal magnetic field 14.
本発明の特徴とするところは、上記MR素子１
６〜１９には幅方向に印加される信号磁界のほか
に、ほぼ長手方向に、スケールブロツク８の裏面
にある、磁気記憶媒体１１内のｙ方向の磁化１２
から発生するバイアス磁界１５が印加されてお
り、これによつて、MR素子１６〜１９の異方性
分散が軽減されていることにある。 The feature of the present invention is that the above MR element 1
6 to 19, in addition to the signal magnetic field applied in the width direction, the magnetization 12 in the y direction in the magnetic storage medium 11 on the back surface of the scale block 8 is applied almost in the longitudinal direction.
A bias magnetic field 15 generated from the MR elements 16 to 19 is applied thereto, thereby reducing anisotropic dispersion of the MR elements 16 to 19.
このため各MR素子１６〜１９は第１図６で示
した特性曲線に固定されるので、波形歪がなくな
り、その結果前記スペーシングＤを大きくしても
良好な位置信号が得られることになり、測長器を
安価にすることができる。 For this reason, each MR element 16 to 19 is fixed to the characteristic curve shown in FIG. , the length measuring device can be made inexpensive.
第４図は再生回路例、第５図は信号磁界１４の
再生過程を示す図である。例えば、第５図ａに模
式的に示す繰り返し磁化を有するスケールブロツ
ク８がMRセンサー１３に対してｘ方向の相対運
動によつて、第３図の矢印２８の方向に移動する
と、この移動に伴う磁気信号１４の繰り返しによ
つて、MR素子１６の出力端子には、第５図ｂの
２２に示す様な信号出力を生じる。同様にして、
MR素子１６と1/2Ｐだけ離れた位置にあるMR素
子１８の出力端子には、２２より、位相が1/2Ｐ
だけ遅れた信号出力２３を生じる。ここで、信号
出力波形２２，２３は、本発明の特徴である、
MR素子の異方性分散の軽減効果によつて、信号
磁界１４に対応した、波形歪の少い良好なものと
なつている。さらに、これらを差動増幅器２０を
通して得られる信号出力２４（第５図ｃ）に変換
し、比較レベル（Vc）２５を基準に、コンパレ
ータ２１にて、パルス化することにより、磁気記
憶媒体９の各ビツトに正確に対応した、角度信号
（Ａ相出力）２６（第５図ｄ）を得ることができ
る。同様にして、MR素子１７と１９からは、Ａ
相出力２６に対して、1/4Ｐだけ位相が遅れた角
度信号（Ｂ相出力）２７（第５図ｅ）を得ること
ができる。ここで、Ａ相出力２６とＢ相出力２７
の位相関係は相対運動方向が逆になると、ちよう
ど逆になる。 FIG. 4 is an example of a reproducing circuit, and FIG. 5 is a diagram showing a reproducing process of the signal magnetic field 14. For example, when the scale block 8 having repetitive magnetization schematically shown in FIG. 5a moves in the direction of the arrow 28 in FIG. By repeating the magnetic signal 14, a signal output as shown at 22 in FIG. 5b is generated at the output terminal of the MR element 16. Similarly,
The output terminal of the MR element 18, which is located 1/2P apart from the MR element 16, has a phase of 1/2P from 22.
produces a signal output 23 delayed by . Here, the signal output waveforms 22 and 23 are characteristic of the present invention.
Due to the effect of reducing the anisotropic dispersion of the MR element, the signal magnetic field 14 has a good waveform with little distortion. Further, these signals are converted into a signal output 24 (FIG. 5c) obtained through a differential amplifier 20, and pulsed by a comparator 21 using a comparison level (Vc) 25 as a reference. An angle signal (A phase output) 26 (FIG. 5d) can be obtained that accurately corresponds to each bit. Similarly, from MR elements 17 and 19, A
An angle signal (B phase output) 27 (FIG. 5e) whose phase is delayed by 1/4P with respect to the phase output 26 can be obtained. Here, the A phase output 26 and the B phase output 27
The phase relationship of is exactly reversed when the direction of relative motion is reversed.
この様にして相対運動による移動量は、Ａ相出
力２６及びＢ相出力２７、もしくは、これらを電
気的に処理して得られる信号パルスをカウントす
ることによつて求められ、また、その移動方向
は、Ａ、Ｂ相出力の位相関係により検出すること
ができる。 In this way, the amount of movement due to the relative movement is obtained by counting the A-phase output 26 and the B-phase output 27, or the signal pulses obtained by electrically processing them, and also by counting the direction of movement. can be detected based on the phase relationship between the A and B phase outputs.
もし、この様なバイアス磁界１５がない場合に
は、MR素子１６〜１８の信号出力波形は第５図
ｆの２８，２９に示す様に歪み、これらの差動増
幅器出力波形も第５図ｇの３０に示す様に歪みを
生じる。この歪が大きくなるとパルス出力３１，
３２（第５図ｈ，ｉ）の位相関係が乱れてしまう
ので、スケールとMRセンサーとの相対移動量及
び移動方向の正確な検出ができなくなる。 If there is no such bias magnetic field 15, the signal output waveforms of the MR elements 16 to 18 will be distorted as shown at 28 and 29 in Fig. 5f, and the output waveforms of these differential amplifiers will also be distorted as shown in Fig. 5g. Distortion occurs as shown in Fig. 30. When this distortion becomes large, the pulse output 31,
32 (h, i in FIG. 5) is disturbed, making it impossible to accurately detect the amount and direction of relative movement between the scale and the MR sensor.
第６図は本発明の第２の実施例を示したもので
ある。この場合はMRセンサー１３にバイアス磁
界を発生する磁気記憶媒体１１がスケールブロツ
ク８の側面に形成されており、その磁化１２によ
つて、MR素子長手方向にバイアス磁界が印加さ
れ、第１の実施例と、同様の動作をする。 FIG. 6 shows a second embodiment of the invention. In this case, a magnetic storage medium 11 that generates a bias magnetic field for the MR sensor 13 is formed on the side surface of the scale block 8, and its magnetization 12 applies a bias magnetic field in the longitudinal direction of the MR element, and the first implementation It works similarly to the example.
次に、本発明の材料、形状及び構成などの例を
示す。スケールブロツク８には、アルミ板が用い
られ、このアルミ板の２面、即ち表側と裏側の
面、又は表側の面と側面に飽和磁化500〜20000ガ
ウス、抗磁力200エルステツド以上、の磁気記憶
媒体が数〜数百ミクロンの厚さに形成される。こ
の磁気記憶媒体としては、Co−Ni等の金属強磁
性体やγ−Fe2O3などが使用される。媒体厚、ビ
ツト長Ｐ及びバイアス用の着磁長Ｌは、用途に応
じて数百ミクロン〜数ミリメートルの大きさに選
択される。特に、バイアス用の磁気記憶媒体１１
の厚み及び着磁長Ｌは、MR素子の長手方向に数
エルステツドのバイアス磁界１５が印加される様
に選択される。 Next, examples of materials, shapes, configurations, etc. of the present invention will be shown. An aluminum plate is used for the scale block 8, and a magnetic storage medium with a saturation magnetization of 500 to 20,000 Gauss and a coercive force of 200 Oersteds or more is placed on two sides of the aluminum plate, that is, the front and back sides, or the front and side faces. is formed to a thickness of several to several hundred microns. As this magnetic storage medium, a metal ferromagnetic material such as Co-Ni or γ-Fe 2 O 3 is used. The medium thickness, bit length P, and bias magnetization length L are selected to range from several hundred microns to several millimeters depending on the application. In particular, the bias magnetic storage medium 11
The thickness and magnetization length L are selected such that a bias magnetic field 15 of several oersteds is applied in the longitudinal direction of the MR element.
MR素子としては、Fe、Ni、Coなどを主成分
とする金属強磁性合金を、シリコン単結晶、ガラ
ス、セラミツク等の表面が滑らかな基板上に、厚
さ数百オングストローム、幅数十ミクロン、長さ
数ミリメートルの形状になる様に、その両端の電
気端子と共に、薄膜作製技術で作製されるものが
用いられる。 The MR element is made of a metal ferromagnetic alloy whose main components are Fe, Ni, Co, etc., on a substrate with a smooth surface such as silicon single crystal, glass, or ceramic, with a thickness of several hundred angstroms and a width of several tens of microns. It is manufactured using thin film manufacturing technology with electrical terminals at both ends so that it has a length of several millimeters.
また、スケールブロツク８として、FeCrCo圧
延磁石材の様に、加工性に富んだ等方的な磁性体
を用い、その２面に、信号磁界発生用の繰り返し
磁化１０及びバイアス用の磁化１２の書き込みを
直接行つても良い。この場合は新たに、磁気記憶
媒体を、形成する手間が省けるので、低価格化を
目指した、測長器に適している。 In addition, as the scale block 8, an isotropic magnetic material with high workability, such as FeCrCo rolled magnet material, is used, and on its two sides, repeated magnetization 10 for signal magnetic field generation and magnetization 12 for bias are written. You can also do this directly. In this case, it is not necessary to newly form a magnetic storage medium, so it is suitable for a length measuring device aiming at low cost.
以上述べた様に、本発明によれば、容易な手段
でMR素子の分散を小さくできるので、測長器の
低価格化及び高性能化が可能になる。 As described above, according to the present invention, it is possible to reduce the dispersion of the MR element by a simple means, thereby making it possible to reduce the cost and improve the performance of the length measuring device.
第１図はMR素子の特性を説明する図、第２図
は一実施例を示す図でａは斜視図、ｂは背面図、
第３図は一実施例の動作を説明する概略斜視図、
第４図は再生回路を示す図、第５図は動作を説明
する図でａは繰り返し磁化の模式図、ｂ〜ｉは波
形図、第６図は他の実施例を示す斜視図である。
１，１６，１７，１８，１９……MR素子、
２，３……異方性分散がある時のMR抵抗変化と
水平方向磁界との関係、４，１４……周期的信号
磁界、５，７……周期的信号磁界に対するMRの
抵抗変化、６……異方性分散が無い時のMR抵抗
変化と水平方向磁界との関係、８……スケールブ
ロツク、９，１１……磁気記憶媒体、１０，１２
……磁化、１３……磁気センサー、１５……バイ
アス磁界、２０……差動増幅器、２１……コンパ
レータ、２２，２３，２８，２９……周期的信号
磁界に対するMRの信号出力、２４，３０……差
動増幅器出力、２５……比較レベル、２６，３１
……Ａ相出力、２７，３２……Ｂ相出力。
Fig. 1 is a diagram explaining the characteristics of the MR element, Fig. 2 is a diagram showing one embodiment, where a is a perspective view, b is a rear view,
FIG. 3 is a schematic perspective view illustrating the operation of one embodiment;
FIG. 4 is a diagram showing a reproducing circuit, FIG. 5 is a diagram explaining the operation, a is a schematic diagram of repeated magnetization, b to i are waveform diagrams, and FIG. 6 is a perspective view showing another embodiment. 1, 16, 17, 18, 19...MR element,
2, 3... Relationship between MR resistance change and horizontal magnetic field when there is anisotropic dispersion, 4, 14... Periodic signal magnetic field, 5, 7... MR resistance change in response to periodic signal magnetic field, 6 ...Relationship between MR resistance change and horizontal magnetic field when there is no anisotropic dispersion, 8...Scale block, 9,11...Magnetic storage medium, 10,12
... Magnetization, 13 ... Magnetic sensor, 15 ... Bias magnetic field, 20 ... Differential amplifier, 21 ... Comparator, 22, 23, 28, 29 ... Signal output of MR for periodic signal magnetic field, 24, 30 ... Differential amplifier output, 25 ... Comparison level, 26, 31
...A phase output, 27,32...B phase output.
Claims (1)
繰り返しの形で記録している磁気記憶媒体が形成
されており、他の面には測長区間にわたつて所定
の幅で測長方向と直角方向に着磁ちれた磁気記憶
媒体が形成されているスケールと、該スケールに
平行に配置され該スケールとの相対運動に伴つて
前記２つの磁気記憶媒体から生じる磁界の変化を
電気抵抗の変化として感知する強磁性磁気抵抗効
果素子より成る磁気センサーとから測長部を構成
していることを特徴とする測長器。 ２ 前記スケールが、圧延磁石材で構成されてお
り、前記磁気記憶媒体を兼ねている特許請求の範
囲第１項に記載の測長器。 ３ 測長方向と直角方向に着磁されている磁気記
憶媒体の作る磁界が強磁性磁気抵抗効果素子のほ
ぼ長手方向に作用する様に配置されている特許請
求の範囲第１項又は第２項に記載の測長器。[Claims] 1. A magnetic storage medium is formed on one surface in which a magnetic signal is recorded in the form of repeated magnetization along the length measurement direction, and on the other surface is formed a magnetic storage medium that records a magnetic signal in the form of repeated magnetization along the length measurement direction. a scale on which a magnetic storage medium is formed that is magnetized in a direction perpendicular to the length measurement direction with a width of A length measuring device characterized in that a length measuring section is constituted by a magnetic sensor made of a ferromagnetic magnetoresistive element that senses changes in a magnetic field as changes in electrical resistance. 2. The length measuring device according to claim 1, wherein the scale is made of rolled magnetic material and also serves as the magnetic storage medium. 3. Claims 1 or 2, wherein the magnetic field generated by the magnetic storage medium that is magnetized in a direction perpendicular to the length measurement direction is arranged so that it acts substantially in the longitudinal direction of the ferromagnetic magnetoresistive element. Length measuring device described in.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4431480A JPS56141514A (en) | 1980-04-04 | 1980-04-04 | Length measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4431480A JPS56141514A (en) | 1980-04-04 | 1980-04-04 | Length measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56141514A JPS56141514A (en) | 1981-11-05 |
| JPS6239683B2 true JPS6239683B2 (en) | 1987-08-25 |
Family
ID=12688018
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4431480A Granted JPS56141514A (en) | 1980-04-04 | 1980-04-04 | Length measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56141514A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58169520U (en) * | 1982-05-07 | 1983-11-12 | ソニ−マグネスケ−ル株式会社 | magnetic scale device |
| JPS59142403A (en) * | 1983-02-02 | 1984-08-15 | Kawaguchiko Seimitsu Kk | Digital vernier caliper |
| JPS59164922U (en) * | 1983-04-18 | 1984-11-05 | 株式会社三協精機製作所 | Magnetic encoder device |
| JPS59195122A (en) * | 1983-04-20 | 1984-11-06 | Keiichiro Taniguchi | Measuring method of land subsidence according to depth and magnetic detector to be used for measurement |
| JPH0781880B2 (en) * | 1988-03-18 | 1995-09-06 | 松下電器産業株式会社 | Magnetic absolute encoder device |
| CN111133023B (en) * | 2017-09-13 | 2022-10-18 | 生活实验公司 | Long-lasting cosmetic composition |
| CN114034222A (en) * | 2021-11-08 | 2022-02-11 | 上海市高级技工学校 | High-precision digital display vernier caliper and measuring method thereof |
-
1980
- 1980-04-04 JP JP4431480A patent/JPS56141514A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56141514A (en) | 1981-11-05 |
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