JPS6129717A - Photoelectric reflection type encoder - Google Patents
Photoelectric reflection type encoderInfo
- Publication number
- JPS6129717A JPS6129717A JP15106784A JP15106784A JPS6129717A JP S6129717 A JPS6129717 A JP S6129717A JP 15106784 A JP15106784 A JP 15106784A JP 15106784 A JP15106784 A JP 15106784A JP S6129717 A JPS6129717 A JP S6129717A
- Authority
- JP
- Japan
- Prior art keywords
- light
- transparent
- reflector
- reflective
- light emitting
- 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.)
- Granted
Links
- 239000011295 pitch Substances 0.000 claims description 25
- 238000007796 conventional method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
- G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
- G01D5/347—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
- G01D5/34707—Scales; Discs, e.g. fixation, fabrication, compensation
- G01D5/34715—Scale reading or illumination devices
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optical Transform (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
産業上の利用分野
この発明は、例えば工作機械の回転テーブルの回動角度
の検出、あるいは往復動テーブルの直線移動距離の検出
等に利用される光電式反射型エンフーグに関する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a photoelectric reflective enfug that is used, for example, to detect the rotation angle of a rotary table of a machine tool, or to detect the linear movement distance of a reciprocating table. .
従来の技術
第２図は、直線移動距離の検出に利用されるものの従来
技術の原理を説明するためのものである。これは細巾の
板状体の、微小一定距離ごとにスリット状の透光部１１
，１１．・・・と遮光部１２，１２．・・・を等間隔で
同じ巾に交互に形成した透光体１０と、上記と同じよう
に反射部２３，２３．・・・と非反射部２４，２４．・
・・が交互に形成された反射体２０とを間隔を有して重
合状態にし、その透光体１０の外面と対向させて投受光
部１を配設したものであり、投受光部から発光させた略
平行光を透光部１１．ＩＬ・・・を介して反射体２０に
照射し、その照射光のうち反射部２３，２３．・・・で
反射し、再び透光部Ｉ Ｌｌｌ、・・・を通過した光を
投受光部１で受け、その受光量に対応した電圧を発生さ
せるようにしたものである。尚、通常は透光体１０９反
射体２０のいずれが一方を静止させ、他方を被検出対象
と一体化させるが、両者を異なる移動体に結合して相対
移動量を検出することもあり、その場合には、投受光部
１もいずれか一方と結合することになる。以上のものに
おいては、透光体１０と反射体２０とがそのピッチ（透
光部１１，１１．・・、反射部２３，２３．・・・の配
列間隔）分だけ相対移動するごとに、透光部１１，１１
．・・と反射部２３，２３．・・・の重合面積が周期的
に変化し、その結果、投受光部の受光量も周期的に変わ
り、投受光部からは周期的に変化する交番電圧信号が取
り出される。したがって、この交番電圧信号の周期数を
測定することにより透光体１０と反射体２０の相対移動
量が求められる。BACKGROUND OF THE INVENTION FIG. 2 is a diagram for explaining the principle of a conventional technique used to detect linear movement distance. This is a thin plate-like body with slit-shaped transparent parts 11 at every minute constant distance.
, 11. ... and the light shielding parts 12, 12 . The transparent body 10 is formed alternately with the same width at equal intervals, and the reflective parts 23, 23 . ... and non-reflective parts 24, 24 .・
... are formed alternately with the reflectors 20 at intervals, and the light emitting/receiving section 1 is disposed to face the outer surface of the transparent body 10, and light is emitted from the light emitting/receiving section. The almost parallel light is transmitted to the transparent section 11. The reflector 20 is irradiated with the light through the IL..., and part of the irradiated light is transmitted to the reflector 23, 23. . . , and passes through the light-transmitting portions I Lll, . Normally, one of the translucent body 109 and the reflector 20 is kept stationary and the other is integrated with the object to be detected, but there are cases where the two are connected to different moving bodies and the amount of relative movement is detected. In this case, the light emitting/receiving section 1 will also be coupled to either one. In the above, each time the transparent body 10 and the reflector 20 move relative to each other by the pitch (the arrangement interval of the transparent parts 11, 11..., the reflective parts 23, 23...), Transparent parts 11, 11
．． . . . and the reflecting portions 23, 23. ... changes periodically, and as a result, the amount of light received by the light emitting/receiving section also changes periodically, and a periodically changing alternating voltage signal is extracted from the light emitting/receiving section. Therefore, by measuring the number of cycles of this alternating voltage signal, the amount of relative movement between the transparent body 10 and the reflector 20 can be determined.
尚、」二記は直線移動距離の検出用のものであるが、回
動角度の検出用は、透光体１０、反射体２０のいずれか
一方または両方を円板の周辺に形成する点が異なるだけ
で、他は何等異なる点はない。Note that item 2 is for detecting the linear movement distance, but for detecting the rotation angle, one or both of the transparent body 10 and the reflector 20 are formed around the disk. There's nothing different about it other than the difference.
ところで、この種のものの検出分解能は、透光部１１，
１１．・・・と反射部２３，２３゜・・・のピッチによ
り決定されることになり、結局、高分解能のものを形成
するには、それだけピッチを小さくしなければならず、
製作および価格のいずれの面でも制約がある。By the way, the detection resolution of this kind of thing is as follows:
11. . . . and the pitch of the reflecting portions 23, 23° .
There are restrictions in terms of both production and price.
発明が解決しようとする問題点
本発明は、高分解能の充電式反射力エンフーグを実現す
るに際してピッチの微小化を解決しようとするものであ
る。Problems to be Solved by the Invention The present invention attempts to solve the problem of miniaturization of the pitch when realizing a high-resolution rechargeable reflective force enfug.
問題点を解決するための手段
本発明は、所定ピッチごとに反射部が形成された反射体
と、所定ピッチごとに透光部が形成された透光体とを重
合させ、透光体の外側に投受光部を配設し、反射体と透
光体との相対移動量を光電的に検出するようにしだ光電
式反射型エンコーダにおいて、前記反射体の反射部をそ
の配列ピッチの５０％より小とし、投受光部は散乱光に
したものである。Means for Solving the Problems The present invention involves polymerizing a reflector in which reflective portions are formed at predetermined pitches and a transparent body in which transparent portions are formed in predetermined pitches. In a photoelectric reflective encoder, a light emitting/receiving section is disposed at a distance of 50% of the arrangement pitch of the reflective section of the reflector, and the relative movement amount between the reflector and the translucent body is detected photoelectrically. It is small in size, and the light emitting/receiving section emits scattered light.
良歴
投受光部からは散乱光が透光体上に放射され、その透光
部を通過した光が反射体上に種々の入射角で照射される
。この結果、入射角により光の到達する反射部およびそ
の位置が異なり、それにより反射部からの反射光の反射
角も種々の方向となり、その反射光のうち再び透光体の
透光部に達した尼のみが投受光部に導入される。このよ
うにして最終的に投受光部に達する光量の大きさは、透
光体の透光部と反射体の反射部との対向位置関係に応し
て変わり、完全対向状態およびその配列ピンチの１／２
ずれた状態で最大、配列ピンチの１／４、および３／４
ずれた状態で最小となり、その最大、最小間は単調に変
化する。この結果、投受光部には、透光体と反射体が相
対的に１ピツチ移動するごとに２周期の周期的変化を生
ずる交番電圧が発生する。Scattered light is emitted from the light emitting/receiving section onto the transparent body, and the light that has passed through the transparent section is irradiated onto the reflector at various incident angles. As a result, the reflective part that the light reaches and its position differ depending on the incident angle, and as a result, the angle of reflection of the reflected light from the reflective part also varies in various directions, and some of the reflected light reaches the transparent part of the transparent body again. Only the reflected light is introduced into the light emitting/receiving section. In this way, the amount of light that finally reaches the light emitting/receiving section changes depending on the facing positional relationship between the transparent part of the transparent body and the reflective part of the reflector, and the amount of light that finally reaches the light transmitting and receiving part changes depending on the facing positional relationship between the transparent part of the transparent body and the reflective part of the reflector. 1/2
Maximum at offset, 1/4 of alignment pinch, and 3/4
It reaches a minimum in the shifted state, and changes monotonically between the maximum and minimum. As a result, an alternating voltage is generated in the light emitting/receiving section, which causes two periodic changes each time the transparent body and the reflector move one pitch relative to each other.
実施例
第１図は本発明の直線移動距離検出用のものについての
実施例であり、前記第２図と同番号を付した透光体１０
は、第２図と同様のものであり、同じ幅の透光部１１，
１１．・・と非透光部１２が交互に形成されている。そ
の透光体１（）と対向して配設されたのが反射体２０で
あり、反射部２３’ 、２３′、・・・と非反射部２４
’ 、２４’ 、・・・とが交互に形成され、その反射
部２３′、・・・の配列ピッチは前記透光体１０の透光
部１１．・・のピッチと等しく、その巾は非反射部２４
′・・の中より小となり、図では反射部２３′はピッチ
の５０％より小さい例えば２５％に形成されている。そ
して、前記透光体１０の外側には散乱光源を有する投受
光部１′が配設されている。Embodiment FIG. 1 shows an embodiment of the present invention for detecting linear movement distance, in which a transparent body 10 with the same number as in FIG.
is the same as that shown in FIG.
11. ... and non-transparent parts 12 are formed alternately. A reflector 20 is disposed facing the transparent body 1(), and includes reflective parts 23', 23', . . . and non-reflective parts 24.
', 24', . . . are formed alternately, and the arrangement pitch of the reflective portions 23', . The width is equal to the pitch of the non-reflective portion 24
In the figure, the reflecting portion 23' is formed to have a pitch smaller than 50%, for example, 25%. A light projecting/receiving section 1' having a scattering light source is disposed outside the transparent body 10.
以１−のものにおいては、投受光器１′から放射された
散乱光のうち透光部＋１．１１．・・を通過した光は反
射体２０″上に放射され、その入射角は種々の角度とな
り、透光部】】。In the following 1-, among the scattered light emitted from the light emitter/receiver 1', the transparent portion +1.11. The light that has passed through is radiated onto the reflector 20'', and the angle of incidence thereof is various, and the light transmitting part]].
１１、・・・と反射部２３′、２３′、・・・の対向位
置関係に応して入射光の到達する反射部２３′、２３′
、・・とその反射部２３′２３′、・・・上の到達位置
が異なり、さらに、その反射部２３’、２３’により反
射した光のうち再び透光部１１．１１を介して投受光部
１′に戻る光量も異なる。11, . . . and the reflecting portions 23', 23', .
, . . . and the reflecting portions 23', 23', . The amount of light returning to section 1' is also different.
第３〜６図は、上記の透光部１１，１１．・・と反射部
２３’ 、２３’ 、・・・どの対向位置関係と一つの
透光部１１を通過した光のうち再び投受光部１′に達す
る光の割合を投光点を横軸にモデル化して示したもので
あり、ここには、投受光部１′と透光体１０間、透光体
１０と反射体２０′間の各間隔をそれぞれ反射部２３
’ 、２３’ 、・・・（透光部１１゜１１、・・）の
配列ピッチと同一および１／２倍とし、反射部２３′、
２３’ 、・・・はそのピッチの２５％としである。第
３図の状態は透光部１１，１１．・・・と反射部２３′
。3 to 6 show the above-mentioned light-transmitting parts 11, 11. ... and the reflecting sections 23', 23', . . . The proportion of the light that passes through one transparent section 11 and reaches the light emitting/receiving section 1' again is expressed with the light emitting point as the horizontal axis. This is modeled and shown here, and the distances between the light emitting/receiving section 1' and the light-transmitting body 10 and between the light-transmitting body 10 and the reflector 20' are shown in the reflection section 23, respectively.
' , 23', ... (transparent parts 11°11, ...) are set at the same pitch and 1/2 times, and the reflecting parts 23',
23', . . . are 25% of the pitch. In the state shown in FIG. 3, the transparent parts 11, 11. ... and the reflecting section 23'
.
２３゛、・・・が１／２ピツチずれ、第４図は第３図の
状態から反射体２０′が１／４ピツチ分左方にずれ、＠
５図は第３図の状態から反射体２０″が左方に １／２
ピツチずれて透光部１１，１１．・・と反射部２３′が
完全に対向し、第６図は第３図の状態から反射体２（ビ
が左方に３／４ピツチずれた状態を示している。矢印付
の線により囲まれた面積は投受光体１′のある１点から
の散乱光のうち透光体１０の中央部の−っの透光部１１
を通過して反射体２０′上に放射される光線を示し、そ
の中のハツチング部分は反射部２３′１こより反射され
る光量を示し、各図の下側は、」二記透光部１１を通過
する全光量に対し、その中で反射部２３′により反射し
、さらに再び透光部１１（必ずしも入射光の通過した透
光部１１とは一致するとは限らない）を介して投受光部
に戻った光景の割合を百分率で示したものである。23゛, .
In Figure 5, the reflector 20'' is moved to the left by 1/2 from the state in Figure 3.
The transparent parts 11, 11. ... and the reflecting part 23' are completely opposed to each other, and FIG. 6 shows a state in which the reflector 2 (B) is shifted by 3/4 pitch to the left from the state in FIG. 3. It is surrounded by a line with an arrow. Of the scattered light from a certain point of the light transmitting and receiving body 1', the area of
The hatched part in the figure shows the amount of light reflected from the reflective part 23'1, and the lower part of each figure shows the light rays that pass through the reflector 20' and are emitted onto the reflector 20'. The total amount of light that passes through is reflected by the reflecting section 23', and then passes through the light transmitting section 11 (not necessarily the same as the light transmitting section 11 through which the incident light has passed) again to the light emitting/receiving section. It shows the proportion of the sights that returned to normal as a percentage.
各状態とも透光部１１を通り、反射体２０′上に透光さ
れる光量は一定であるが、透光部１１と反射部２３′の
対向位置関係に応じて反射部２３′に到達する光量およ
びその反射光量のうち非透光部１２によっで遮ぎられる
光量が変化し、投受光部に戻る光量の大きさは第３、第
５の状態、すなわち透光部１１と反射部２３′の完全重
合状態および１／２ピツチずれた状態で最大、第４．６
図の状態、すなわち上記両者が １／４．３／４ピツチ
ずれた状態で最小となり、その最大と最小、最小と最大
の間は単調に減増する。In each state, the amount of light that passes through the transparent section 11 and onto the reflector 20' is constant, but the amount of light that reaches the reflective section 23' depends on the opposing positional relationship between the transparent section 11 and the reflective section 23'. Of the amount of light and the amount of reflected light, the amount of light blocked by the non-transparent part 12 changes, and the amount of light returning to the light emitting/receiving part changes between the third and fifth states, that is, the transparent part 11 and the reflecting part 23. ' is maximum in the fully polymerized state and in the state shifted by 1/2 pitch, No. 4.6
The state shown in the figure, that is, the state where both of the above are shifted by 1/4 and 3/4 pitches, is the minimum, and the maximum and minimum, and between the minimum and maximum, decrease and increase monotonically.
以上は、特定の一つの透光部を通過する光量に注目した
ものであるが、他の透光部を通過する光量に対しても透
光部を通過した光量に対する投受光部に戻る光量の割合
を示す／メターンは同一（但し、位相はずれる）であり
上記／７−１ｎ ＋ ａ ｌｋ ７７１ ｍ ｊＸ
Ｉ十恋ｈ ！、 ｈ イー １−た力ｆ４て、投受光
？￥１！１′からは、導入される反射光量に対応した電
圧信号、すなわち、透光体１０と反射体２０′とが相対
的に１７２ピツチ移動するごとに周期的に変化する交番
電圧信号が発生することになり、結局、従来技術のもの
に比べて２倍の分解能を有する交番電圧信号となる。The above focuses on the amount of light passing through one specific transparent part, but the amount of light returning to the light emitting/receiving part relative to the amount of light passing through other transparent parts is also Showing the ratio/Methanes are the same (however, out of phase) and the above/7-1n + a lk 771 m jX
I ten love h! , h e 1-force f4, light emitting and receiving? From ¥1!1', a voltage signal corresponding to the amount of reflected light introduced, that is, an alternating voltage signal that changes periodically every time the transparent body 10 and the reflector 20' move 172 pitches relative to each other. The result is an alternating voltage signal with twice the resolution compared to that of the prior art.
尚、上記実施例においては、投受光部１′と透光体１０
間、透光体１０と反射体２０間をそれぞれ透光部ピッチ
と同じおよび１／２倍とした場合であるが、これに限定
されるものではなく、適宜に選定しても同様であり、ま
た、反射部のピッチに占める割合も５０％より小さい適
宜の割合としてよい。In the above embodiment, the light emitting/receiving section 1' and the transparent body 10
In this case, the distance between the transparent body 10 and the reflector 20 is set to be the same as the pitch of the transparent part and 1/2 times the pitch, respectively, but the pitch is not limited to this, and the same can be done even if the pitch is appropriately selected. Further, the ratio of the reflection portion to the pitch may be set to an appropriate ratio smaller than 50%.
発明の効果
本発明は、反射体の反射部ピッチに対する反射部の割合
を５０％より小とし、投受光部の光源を散乱光源とする
ことにより従来技術の２倍の分解能を有する出力を取り
出すようにしたものであり、高分解能化が制作面、経済
面のいずれの面でも容易となり、高分解能な回動角、距
離の検出が容易に実現される。Effects of the Invention The present invention makes the ratio of the reflecting part to the reflecting part pitch of the reflector smaller than 50%, and uses a scattering light source as the light source of the light emitting/receiving part, so as to extract an output with twice the resolution of the conventional technology. This makes it easy to achieve high resolution both from a production and economic perspective, and enables high-resolution detection of rotation angles and distances.
第１図は本発明の実施例を示す正面図、第２図は従来技
術を示す正面図、第３〜６図は本発明の動作説明図であ
る。
１′二投受光体 １０：透光体FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a front view showing a conventional technique, and FIGS. 3 to 6 are explanatory diagrams of the operation of the present invention. 1' Double throw light receiver 10: Translucent body
Claims (1)
定ピッチごとに透光部が形成された透光体とを間隔を介
して重合させ、透光体の外側に投受光部を配設し、反射
体と透光体との相対移動量を光電的に検出するようにし
た光電式反射型エンコーダにおいて、反射体の反射部を
そのピッチの５０％より小とし、投受光部は、投光を散
乱光にしたところの光電式反射型エンコーダ。1. A reflector in which reflective portions are formed at predetermined pitches and a transparent body in which transparent portions are formed at predetermined pitches are overlapped with each other at intervals, and a light emitting/receiving portion is arranged on the outside of the transparent body. In a photoelectric reflective encoder in which the amount of relative movement between a reflector and a transparent body is detected photoelectrically, the reflective part of the reflector is made smaller than 50% of the pitch thereof, and the light emitting/receiving part is A photoelectric reflective encoder that converts the projected light into scattered light.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15106784A JPS6129717A (en) | 1984-07-20 | 1984-07-20 | Photoelectric reflection type encoder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15106784A JPS6129717A (en) | 1984-07-20 | 1984-07-20 | Photoelectric reflection type encoder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6129717A true JPS6129717A (en) | 1986-02-10 |
| JPH0253727B2 JPH0253727B2 (en) | 1990-11-19 |
Family
ID=15510577
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15106784A Granted JPS6129717A (en) | 1984-07-20 | 1984-07-20 | Photoelectric reflection type encoder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6129717A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63501381A (en) * | 1986-07-03 | 1988-05-26 | レニショウ パブリック リミテッド カンパニー | Optical-electronic scale reader |
-
1984
- 1984-07-20 JP JP15106784A patent/JPS6129717A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63501381A (en) * | 1986-07-03 | 1988-05-26 | レニショウ パブリック リミテッド カンパニー | Optical-electronic scale reader |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0253727B2 (en) | 1990-11-19 |
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