JPS5872771A - Piston position detector in cylinder - Google Patents

Piston position detector in cylinder

Info

Publication number
JPS5872771A
JPS5872771A JP17169881A JP17169881A JPS5872771A JP S5872771 A JPS5872771 A JP S5872771A JP 17169881 A JP17169881 A JP 17169881A JP 17169881 A JP17169881 A JP 17169881A JP S5872771 A JPS5872771 A JP S5872771A
Authority
JP
Japan
Prior art keywords
cylinder
piston
rod
permanent magnets
permanent magnet
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.)
Pending
Application number
JP17169881A
Other languages
Japanese (ja)
Inventor
Giichi Kawashima
川島　義一
Kazuo Ito
一夫 伊藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Azbil Corp
Original Assignee
Azbil Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Azbil Corp filed Critical Azbil Corp
Priority to JP17169881A priority Critical patent/JPS5872771A/en
Publication of JPS5872771A publication Critical patent/JPS5872771A/en
Pending legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/28—Means for indicating the position, e.g. end of stroke
    • F15B15/2807—Position switches, i.e. means for sensing of discrete positions only, e.g. limit switches
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/28—Means for indicating the position, e.g. end of stroke
    • F15B15/2892—Means for indicating the position, e.g. end of stroke characterised by the attachment means

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Actuator (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)

Abstract

PURPOSE:To detect certainly the position of a piston easily by mounting permanent magnets on a piston rod and by mounting proximity switches including magnetically sensitive elements inside on a supporting member supporting said piston rod. CONSTITUTION:A cylinder 1 is made of iron, etc. so as to sufficiently stand a high pressure. Permanent magnets 19, 20 are mounted on a piston rod 16 at the both sides of a piston 17. In mounting holes 7, 8 formed on a rod supporting member 2, 3, proximity switches 21, 22 are screwed in, while those switches detect the magnetic flux caused from said permanent magnets 19, 20 due to approach of said magnets 19, 20. Said proximity switches 21, 22 are so constructed that magnetically sensitive elements 26 are housed in cases 25 made of a non-magnetic material such as a stainless steel SUS 304, etc. Sensive surfaces 27 of said switches 21, 22 are positioned as close as possible to said permanent magnets 19, 20.

Description

【発明の詳細な説明】 この発明はシリンダーのピストン位置を検出する装置Ｃ
二関する。DETAILED DESCRIPTION OF THE INVENTION This invention provides an apparatus C for detecting the position of a piston in a cylinder.
Two matters.

従来のシリンダーとして第１図に示すようにシリンダ一
部４をアルミニウムや合成樹脂の管により形成し、ピス
トン本体１７に永久磁石１９を設けるとともＣニジリン
ダ一部４の外側に永久磁石１９の磁束を検出するリード
スイッチ２１を増付け、このリードスイッチと永久磁石
１９の相対的な位置関係によってピストン１５０位阪を
検出するものがあるが、シリンダ一部４の材質からして
空気圧（二は使用ｈ］能であっても油圧等の液圧のばあ
いにはシリンダーに加わる圧力は空気圧に比べてはる〃
≧に高いため、使用に耐えない。As a conventional cylinder, as shown in FIG. 1, the cylinder part 4 is formed of an aluminum or synthetic resin tube, and the piston body 17 is provided with a permanent magnet 19, and the magnetic flux of the permanent magnet 19 is installed outside the cylinder part 4. Some systems add a reed switch 21 to detect the piston and detect the piston 150 position by the relative positional relationship between the reed switch and the permanent magnet 19.However, due to the material of the cylinder part 4, the air pressure h] Even if the cylinder is equipped with hydraulic pressure, the pressure applied to the cylinder is much higher than that of air pressure.
≧ high, so it cannot be used.

そこでシリンダ一部４を耐圧の高い金属により形成する
ことが考えられるが、ピストンの位置を検出する検出端
としてリードスイッチを用いるばあいにはシリンダ一部
４を非磁性体の金属で形成することが必要条件となる。Therefore, it is possible to form the cylinder part 4 from a metal with high pressure resistance, but if a reed switch is used as a detection end for detecting the position of the piston, the cylinder part 4 may be formed from a non-magnetic metal. is a necessary condition.

その金属としてはたとえば８Ｕ８３０４等の非磁性体の
ステンレススチールが考えられる。As the metal, non-magnetic stainless steel such as 8U8304 can be considered.

しかし、油圧シリンダーの工うな液圧シリンダーのシリ
ンダ一部の材質としては一般に鉄であり、これを非磁性
体のステンレススチールに変更することは大幅な原価高
を招く欠点がある。However, the material of a cylinder part of a hydraulic cylinder, such as a hydraulic cylinder, is generally iron, and changing this to non-magnetic stainless steel has the disadvantage of significantly increasing costs.

この発明はこのような欠点を解消し工すとするもので、
以下図によってこの発明の一実施例を設問する。This invention aims to eliminate these drawbacks.
The following questions will explain one embodiment of this invention using the diagrams.

すなわち第２図において、シリンダーｌは高いＨ−力Ｃ
二十分耐え得るたとえば鉄等により形成されたシリンダ
一部４を有し、このシリ二ノダー１１〜の両端部じはロ
ッド支′Ｎｌ！ｄｓ２．３’が設けられている。That is, in FIG. 2, the cylinder l has a high H-force C
It has a cylinder part 4 made of, for example, iron, which can withstand twenty minutes, and both ends of this cylinder cylinder 11~ are rod supports 'Nl! ds2.3' is provided.

そしてこのロッド支持部にはそれぞれ配管連結用の穴５
．６が名１個ずつ設けられ、しかもロッド支持部２，３
には穴５．６に対し拉げ９０川゛ずれた位置に後述する
近接スイッチを増重けるための取付は穴７，８が設けら
れている。またロッド支持部２，３はこれらをそれぞれ
１通する連結杆９．１０と、ナツト１１．１２＋二Ｌリ
シ１７ンタ゛一部４に一体的に取付けられている。ピス
トン１５のロッド１６はシリンダ一部４および両ロッド
支持部２，３を貫通し、かつ両ロッド支持部２，３に摺
動自在に支持されている。さらにロッド１６にはピスト
ン部１７が固足され、このピストン部はシリンダ一部４
内ｔ−おいてこのシリンダ一部に摺動自在に案内されて
いる。ピストン部Ｌ７の両側部におい千ロッド１６には
たとえばフェライト磁石等の永久磁石１９．２０が取付
けられている。Each rod support has a hole 5 for connecting the pipe.
．． 6 is provided one each, and the rod support parts 2 and 3 are
Holes 7 and 8 are provided at positions offset by 90 degrees from holes 5 and 6 for mounting a proximity switch, which will be described later, in order to increase its weight. Further, the rod support parts 2 and 3 are integrally attached to a connecting rod 9.10 that passes through each of these parts, and a nut 11.12 + two L ribs 17 and a counter part 4. The rod 16 of the piston 15 passes through the cylinder part 4 and both rod supports 2 and 3, and is slidably supported by both rod supports 2 and 3. Further, a piston part 17 is fixedly attached to the rod 16, and this piston part is connected to the cylinder part 4.
It is slidably guided by a part of this cylinder at the inner part. Permanent magnets 19, 20, such as ferrite magnets, are attached to the rods 16 on both sides of the piston portion L7.

取付は穴７，８には永久磁石１９．２０が発生する磁束
をその磁石の接近に１って検出する近接スイッチ２１．
２２が螺合されている。そしてこの近接スイッチは第３
図に示すよう（二たとえばステンレススチールＳ　Ｕ　
８　：（０４黄銅、＃Ｌ　ｖｔ銅等の非磁性体金属やセ
ラミック等の非磁性体に工す形成されたケース２５内に
たとえば磁気抵抗素子。Proximity switches 21. are installed in holes 7 and 8 to detect the magnetic flux generated by permanent magnets 19.20 when the magnets approach.
22 are screwed together. And this proximity switch is the third
As shown in the figure (for example, stainless steel S
8: (For example, a magnetoresistive element is placed inside the case 25 formed of a non-magnetic metal such as 04 brass or #L VT copper or a non-magnetic material such as ceramic.

ホール効果素子あるい’ｄ　＋７−ドスイツチ等の感磁
性素子２６ｆ収容することにエリ構成されている。また
近接スイッチ２１．２２はロッド支持部２．３（二取付
けた状態でロッド１６すなわち永久磁石１９．２０に対
し、その感応面２７が極力接近するように位置している
。It is designed to accommodate a magnetically sensitive element 26f such as a Hall effect element or a +7-de switch. Further, the proximity switch 21.22 is located so that its sensitive surface 27 is as close as possible to the rod 16, that is, the permanent magnet 19.20 when the rod support 2.3 (2) is attached.

近接スイッチ２１．２２とロッド支持部２．３との間に
は両者間のシールを司る（１リング２９゜３０が設けら
れ、またピストン部１７にはこのピストン部とシリンダ
一部４との間のシールを司るピストンリング３１が設け
られている。A ring 29.30 is provided between the proximity switch 21.22 and the rod support 2.3 to provide a seal between the two, and the piston 17 has a ring 29. A piston ring 31 is provided for sealing.

なお第４図は感磁性素子として磁気抵抗素子を用いて構
成した近接スイッチの回路を示すもので、４１は磁気抵
抗素子のブリッジ回路１ｍ　、［：り構成した検出部、
４２はこの検出部で発生し一＃信号を増幅する増幅部、
４３はこの増幅部の出力佃′号に工っで動作するスイッ
チング部、、４４１ｄ−出力部、ぞして４５はこの出力
部とスイッチング部４３との間に設けた動作表示灯アあ
る。そしてこれらの回路はプリント回路基板２８Ｆに形
成され、感磁性素子２６とともにケース２５内に収容さ
れている。Note that FIG. 4 shows a circuit of a proximity switch constructed using a magnetoresistive element as a magnetically sensitive element, and 41 is a bridge circuit 1m of magnetoresistive elements;
42 is an amplification unit that amplifies the 1# signal generated in this detection unit;
Reference numeral 43 denotes a switching section which operates based on the output number of this amplifying section, 441d - an output section, and 45 an operation indicator light provided between this output section and the switching section 43. These circuits are formed on a printed circuit board 28F and housed in the case 25 together with the magnetically sensitive element 26.

上記構成において、今、一方の穴５炉ら流体が圧入され
るとピストン１５は第２図において右方へ移動し、他方
の永久磁石２０が他方の近接スイッチ２２の感応面に接
近する。同時にケース２５内に収容された感磁性素子２
６が永久磁石２０の磁束の変化を受けて検出信号を発生
し、ピストン１５が右方に所定の距離だけ移動したこと
が検出される。この検出信号は第４図【：おいては磁気
抵抗素子のブリッジ回路の不平衝１：よって発生し、こ
の信号は増幅部４２お工びスイッチング部４３を経て出
力部４４から出力される。In the above configuration, when fluid is now pressurized from one hole 5, the piston 15 moves to the right in FIG. 2, and the other permanent magnet 20 approaches the sensitive surface of the other proximity switch 22. Magnetically sensitive element 2 housed in case 25 at the same time
6 generates a detection signal in response to a change in the magnetic flux of the permanent magnet 20, and it is detected that the piston 15 has moved a predetermined distance to the right. This detection signal is generated by the unbalanced impingement 1 of the bridge circuit of the magnetoresistive element in FIG.

また他方の穴６から流体が圧入されるとピストン１５は
第２図において、前とは逆に左方へ移動し、一方の永久
磁石１９が一方の近接スイッチ２１の感応面に接近する
。同時にケース２５内に収容された感磁性素子２６が永
久磁石１９の磁束の変化を受けて検出信号を発生し、ピ
ストン１５が左方へ所定の距離だけ移動したことが検出
されるなお上記構成において取付は穴７，８、近接スイ
ッチ２１．２２および永久磁石１９．２０をそれぞれ一
対ずつ設けたものＣついて説明したが。When fluid is forced into the other hole 6, the piston 15 moves to the left in FIG. At the same time, the magnetically sensitive element 26 housed in the case 25 generates a detection signal in response to a change in the magnetic flux of the permanent magnet 19, and detects that the piston 15 has moved a predetermined distance to the left. The installation has been described with reference to C, in which a pair of holes 7 and 8, a proximity switch 21, 22, and a pair of permanent magnets 19, 20 are provided.

これらは必要に応じて片方だけ用いることも可能である
。It is also possible to use only one of these as needed.

この発明は上述のようにピストン１５のロッド１６に永
久磁石を取付け、またこのロッドな支持するロッド支持
部には永久磁石の発生する磁束を検出する近接スイッチ
を設け、しかもこの近接スイッチは非磁性体のケース２
５内に感磁性素子２６を収容することにより構成してい
るので、高耐圧のシリンダーを得ることができるととも
に、ピストンの位置を容易に、かつ確実にわ１１出でき
、さらに従来のシリンダーに比し、製造原価をさＩｆど
上昇させることなく構成できる利点がある。In this invention, as described above, a permanent magnet is attached to the rod 16 of the piston 15, and a proximity switch for detecting the magnetic flux generated by the permanent magnet is provided on the rod support part that supports this rod.Moreover, this proximity switch is non-magnetic. body case 2
Since the magnetic element 26 is housed within the cylinder 5, it is possible to obtain a cylinder with high pressure resistance, and the position of the piston can be easily and reliably set. However, it has the advantage that it can be constructed without increasing manufacturing costs.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は従来のシリンダーを示す正断面図、第２図はこ
の発明におけるシリンダーを一部９１欠いて示す斜視図
、第３図は正断面図、第４図は近接スイッチの回路図で
ある。なお図中同一符号は同一または和尚部分を示す。 １・・・シリンダー、２，３・・・ロッド支持部、４・
・・シリンダ一部、５，６・・・穴、７，８・・・取付
は穴、９．１０・・・連結杆、１１．１２・・・ナツト
、１５・・・ピストン、１６・・・ロッド、１７・・・
ピストン部、１９．２０・・・永久磁石、２１．２２・
・・近接スイッチ、２５・・・ケース、２６・・・感磁
性素子、２７パ・感応向、２８・・・プリント回路基板
、２９．：３０・・・０リング、３１・・・ピストンリ
ング、４１・・・検出部、４２・・・増幅部、４３・・
・スイッチング部、４４・・・出力部、４５・・・動作
表示灯。Fig. 1 is a front sectional view showing a conventional cylinder, Fig. 2 is a perspective view showing the cylinder according to the present invention with part 91 removed, Fig. 3 is a front sectional view, and Fig. 4 is a circuit diagram of a proximity switch. . Note that the same reference numerals in the figures indicate the same or similar parts. 1... Cylinder, 2, 3... Rod support part, 4...
・Cylinder part, 5, 6... Hole, 7, 8... Mounting hole, 9.10... Connecting rod, 11.12... Nut, 15... Piston, 16...・Rod, 17...
Piston part, 19.20...Permanent magnet, 21.22.
... Proximity switch, 25... Case, 26... Magnetically sensitive element, 27 Pa/Sensitive direction, 28... Printed circuit board, 29. :30...0 ring, 31...piston ring, 41...detection section, 42...amplification section, 43...
- Switching section, 44... Output section, 45... Operation indicator light.

Claims (2)

【特許請求の範囲】[Claims] （１）　　シリンダー内にピストンを摺動自在に収容す
るとともに、上記シリンダーの両端部に、上記ピストン
のロッドを摺動自在（二支持する一対のロッド支持部を
、上記シリンダーと一体的に設け、かつ上記ピストンの
ロッドには永久磁石を取付け、さらに上記ロッド支持部
には上記永久磁石の発生する磁束を検出する近接スイッ
チを設け、し炉もこの近接スイッチは非磁性体のケース
内に感磁性素子を収容することにＬり構成したシリンダ
ーのピストン位置検出装置。(1) A piston is slidably accommodated in a cylinder, and a pair of rod support parts that slidably support a rod of the piston are provided integrally with the cylinder at both ends of the cylinder, A permanent magnet is attached to the rod of the piston, and a proximity switch is installed on the rod support part to detect the magnetic flux generated by the permanent magnet. A piston position detection device for a cylinder configured in an L shape to accommodate an element. （２）上記ケースを非磁性体金属にエリ形成した特許請
求の範囲第１項記載のシリンダーのピストン位置検出装
置。 （３上記ケースをセラミックに工す形成した特許請求の
範囲第１項記載のシリンダーのピストン位置検出装置。(2) A piston position detection device for a cylinder according to claim 1, wherein the case is formed of a non-magnetic metal with an edge. (3) The cylinder piston position detecting device according to claim 1, wherein the case is made of ceramic.
JP17169881A 1981-10-27 1981-10-27 Piston position detector in cylinder Pending JPS5872771A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17169881A JPS5872771A (en) 1981-10-27 1981-10-27 Piston position detector in cylinder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17169881A JPS5872771A (en) 1981-10-27 1981-10-27 Piston position detector in cylinder

Publications (1)

Publication Number Publication Date
JPS5872771A true JPS5872771A (en) 1983-04-30

Family

ID=15928020

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17169881A Pending JPS5872771A (en) 1981-10-27 1981-10-27 Piston position detector in cylinder

Country Status (1)

Country Link
JP (1) JPS5872771A (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS611704U (en) * 1984-06-11 1986-01-08 三菱重工業株式会社 Cylinder
JPS6130709U (en) * 1984-07-28 1986-02-24 東海オ−トメ−シヨン株式会社 Reed switch mounting structure in piston position detection device in fluid pressure cylinder
JPS6130708U (en) * 1984-07-28 1986-02-24 東海オ−トメ−シヨン株式会社 Piston position detection device in a fluid pressure cylinder
JPS61211571A (en) * 1985-03-12 1986-09-19 フエスト　カーゲー Piston
JPS62134905U (en) * 1986-02-19 1987-08-25
JPS62138905U (en) * 1986-02-25 1987-09-02
EP0271878A2 (en) * 1986-12-16 1988-06-22 Kayaba Kogyo Kabushiki Kaisha Stroke sensor for a fluid-power cylinder
JPS63133602U (en) * 1987-02-24 1988-09-01
JPS6429517U (en) * 1987-08-14 1989-02-22
US4914916A (en) * 1988-04-04 1990-04-10 Automotive Products Plc Tandem master cylinder with electromagnetic position sensors for each piston
US5816778A (en) * 1996-01-16 1998-10-06 Micron Technology, Inc. System for controlling the stroke length of a double-diaphragm pump
WO2010087100A1 (en) * 2009-01-29 2010-08-05 アサ電子工業株式会社 Magnetic proximity switch and magnetic detection switch

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5013754A (en) * 1973-06-11 1975-02-13
JPS5017691B1 (en) * 1973-06-09 1975-06-23

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5017691B1 (en) * 1973-06-09 1975-06-23
JPS5013754A (en) * 1973-06-11 1975-02-13

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS611704U (en) * 1984-06-11 1986-01-08 三菱重工業株式会社 Cylinder
JPH0511366Y2 (en) * 1984-07-28 1993-03-22
JPS6130709U (en) * 1984-07-28 1986-02-24 東海オ−トメ−シヨン株式会社 Reed switch mounting structure in piston position detection device in fluid pressure cylinder
JPS6130708U (en) * 1984-07-28 1986-02-24 東海オ−トメ−シヨン株式会社 Piston position detection device in a fluid pressure cylinder
JPH0511365Y2 (en) * 1984-07-28 1993-03-22
JPS61211571A (en) * 1985-03-12 1986-09-19 フエスト　カーゲー Piston
JPH0524383B2 (en) * 1985-03-12 1993-04-07 Festo Kg
JPS62134905U (en) * 1986-02-19 1987-08-25
JPS62138905U (en) * 1986-02-25 1987-09-02
EP0271878A2 (en) * 1986-12-16 1988-06-22 Kayaba Kogyo Kabushiki Kaisha Stroke sensor for a fluid-power cylinder
JPS63133602U (en) * 1987-02-24 1988-09-01
JPS6429517U (en) * 1987-08-14 1989-02-22
US4914916A (en) * 1988-04-04 1990-04-10 Automotive Products Plc Tandem master cylinder with electromagnetic position sensors for each piston
US5816778A (en) * 1996-01-16 1998-10-06 Micron Technology, Inc. System for controlling the stroke length of a double-diaphragm pump
WO2010087100A1 (en) * 2009-01-29 2010-08-05 アサ電子工業株式会社 Magnetic proximity switch and magnetic detection switch
JP5175330B2 (en) * 2009-01-29 2013-04-03 アサ電子工業株式会社 Magnetic proximity switch and magnetic detection system

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