SI25094A - A magnetic encoder with a protected elasto-ferite layer - Google Patents

A magnetic encoder with a protected elasto-ferite layer Download PDF

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Publication number
SI25094A
SI25094A SI201500272A SI201500272A SI25094A SI 25094 A SI25094 A SI 25094A SI 201500272 A SI201500272 A SI 201500272A SI 201500272 A SI201500272 A SI 201500272A SI 25094 A SI25094 A SI 25094A
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SI
Slovenia
Prior art keywords
layer
elastoferrite
magnetic
encoder
thickness
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Application number
SI201500272A
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Slovenian (sl)
Inventor
Branko Cvetković
Ljubo Slabajna
Janez Novak
Matjaž SIVEC
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RLS merilna tehnika d.o.o. Poslovna cona Žeje pri Komendi
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Priority to SI201500272A priority Critical patent/SI25094A/en
Priority to PCT/SI2016/000023 priority patent/WO2017082831A1/en
Publication of SI25094A publication Critical patent/SI25094A/en

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    • 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
    • G01D5/12—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 using electric or magnetic means
    • G01D5/14—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 using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/20—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 using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
    • 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
    • G01D5/12—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 using electric or magnetic means
    • G01D5/244—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 using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
    • G01D5/24428—Error prevention
    • G01D5/24433—Error prevention by mechanical means
    • G01D5/24438—Special design of the sensing element or scale
    • 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
    • G01D2205/00—Indexing scheme relating to details of means for transferring or converting the output of a sensing member
    • G01D2205/80—Manufacturing details of magnetic targets for magnetic encoders

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Transmission And Conversion Of Sensor Element Output (AREA)

Abstract

Predmet izuma je magnetni dajalnik zasuka z zaščiteno elastoferitno plastjo. Dajalnik položaja je naprava, ki zazna magnetno spremembo, ki se pojavi pri premiku ali zasuku in jo prevede v električni signal. Dajalnik po izumu je značilen po tem, da je najmanj preko zunanje stene plasti (2) elastoferitnega nosilca položena zaščitna plast (3) izdelana iz neferomagnetnega materiala debeline reda 10x manjša od širine magnetnih polov v elastoferitni plasti (2) ali iz feromagnetnega materiala debeline reda 5 - 10x manjša od debeline plasti (3), izdelane iz ne feromagnetnega materiala.Subject of the invention is a magnetic encoder with a protected elastomeric layer. The position encoder is a device that detects a magnetic change that occurs when moving or rotating and translates it into an electrical signal. The enclosure according to the invention is characterized in that at least an outer wall of the layer (2) of the elastomeric support is laid out of a protective layer (3) made of non-ferromagnetic material of a thickness of the order of 10x smaller than the width of the magnetic poles in the elastomeric layer (2) or from the ferromagnetic material of the thickness of the line 5 - 10x smaller than the thickness of the layer (3), made of non ferromagnetic material.

Description

MAGNETNI DAJALNIK ZASUKA Z ZAŠČITENO ELASTOFERITNO PLASTJOMAGNETIC TURNOVER WITH PROTECTED ELASTOPHERITE LAYER

Predmet izuma je magnetni dajalnik zasuka z zaščiteno elastoferitno plastjo.The subject of the invention is a magnetic rotary encoder with a protected elastoferite layer.

Dajalnik položaja je naprava, ki zazna fizikalno spremembo, ki se pojavi pri premiku ali zasuku, in jo prevede v analogni ali digitalni električni signal. V splošnem ga sestavljata dva dela, ki se premikata relativno drug na drugega: nosilec informacije ter čitalna glava, v kateri so senzorji, ki zaznavajo fizikalne spremembe med njenim premikanjem ob nosilcu informacije. Po osnovnem uporabljenem principu zaznavanja fizikalne spremembe so lahko magnetni, optični, kapacitivni, induktivni in drugi. Dajalniki so rotacijski, ki merijo kot ali linearni, ki merijo razdaljo.A position transmitter is a device that detects a physical change that occurs when it is moved or rotated and translates it into an analog or digital electrical signal. Generally, it consists of two parts that move relative to one another: the information carrier and a reading head, which contains sensors that detect physical changes as it moves along the information carrier. According to the basic principle of physical change perception, magnetic, optical, capacitive, inductive and others can be used. Encoders are rotary, measuring angle or linear, measuring distance.

Izum se nanaša na magnetne dajalnike rotacijskega tipa.The invention relates to rotary-type magnetic encoders.

Nosilci informacije magnetnih dajalnikov so:The carriers of magnetic encoder information are:

- Iz feritne keramike:- Ferrite ceramic:

- pomankljivosti: krhkost, kar onemogoča montažo s krčnim nasedom;- imperfections: fragility, which makes it impossible to mount with a shrink lever;

- prednosti: enostavnost, širine magnetiziranih polov so reda velikosti mm, s tem je razdalja med čitalno glavo in obroči lahko večja, nizki proizvajalni stroški, nizka cena, omogočajo visoko ločljivost.- advantages: simplicity, the widths of the magnetized poles are in the order of mm, thus the distance between the reading head and the rings can be larger, low production costs, low cost, allow for high resolution.

- S kovinski nosilci:- With metal mounts:

- pomankljivosti: dragi materiali, za doseganje magnetnih lastnosti, je potrebna termična obdelava, majhne širine magnetiziranih polov (red velikosti 0.1 mm) in s tem majhna tipalna razdalja, občutljivost na površinske poškodbe;- deficiencies: expensive materials, in order to achieve magnetic properties, requires thermal treatment, small widths of magnetized poles (order of size 0.1 mm) and thus a small touch distance, susceptibility to surface damage;

- prednost: dolgoročna metrološka stabilnost, visoka točnost, visoka ločljivost.- Advantage: long-term metrological stability, high accuracy, high resolution.

-2- Z zobniki:-2- With gears:

- pomankljivosti: nizka ločljivost, visoka interpolacijska napaka, zvočna glasnost, visoki začetni proizvajalni stroški zaradi dragih orodij, v čitalni glavi je trajni magnet, zaradi katerega je čitalna glava večja, potreben ščit magnetnega polja, da ta magnet ne privlači opilkov,...- imperfections: low resolution, high interpolation error, sound volume, high initial production costs due to expensive tools, a permanent magnet in the reading head, which makes the reading head larger, a magnetic field shield is required to prevent this magnet from attracting filaments, ...

- prednost: enostavnost, visoke hitrosti.- advantage: simplicity, high speed.

- Z elastoferitni nosilci- With elastoferrite mounts

- pomankljivosti: nedosegljive visoke hitrosti (>20.000 obratov na minuto), vezivni material (NBR, HNBR...) se pospešeno stara zaradi hlapov hladilno mazalnih tekočin;- disadvantages: unreachable high speeds (> 20,000 rpm), binder material (NBR, HNBR ...) is aging rapidly due to the vapors of coolant lubricants;

- prednost: enostavnost, visoka ločljivost, širine magnetiziranih polov so reda velikosti mm in s tem je tudi razdalja med čitalno glavo in ringi lahko večja, nizki proizvajalni stroški.- Advantage: simplicity, high resolution, widths of magnetized poles are of the order of mm, and thus the distance between the reader head and the rings can be larger, low production costs.

Naloga in cilj izuma je omogočanje visokih hitrosti vrtenja rotacijskih dajalnikov z elstoferitnimi nosilci magnetnega zapisa in hkrati njihova zaščita pred škodljivim vplivom hlapov hladilno mazalnih tekočin.The object and object of the invention is to enable high rotational speeds of rotary encoders with elstoferite magnetic record carriers and at the same time to protect them against the harmful effects of vapors of coolant lubricants.

Po izumu je naloga rešena z zaščitno plastjo preko elastoferitnega nosilca.According to the invention, the problem is solved by a protective layer through an elastoferite carrier.

Izum bo opisan s pomočjo slik, ki prikazujejo:The invention will be described by means of pictures showing:

sl. 1: obroč rotacijskega dajalnika v projekciji, sl.2: prerez rotacijskega dajalnika v prvem izvedbenem primeru, sl. 3: prerez rotacijskega dajalnika v drugem izvedbenem primeru, sl. 4: prerez rotacijskega dajalnika v tretjem izvedbenem primeru,FIG. 1 is a projection ring of the rotary encoder, FIG. 2: cross section of the rotary encoder in the first embodiment; FIG. 3 is a sectional view of a rotary encoder in another embodiment; FIG. 4: cross section of the rotary encoder in the third embodiment,

-3Po sliki 1 je rotacijski dajalnik, to je nosilec magnetne informacije obroč, ki se natakne na os ki rotira in omogoča merjenje pozicije, to je kota ali hitrosti vrtenja, to je kotne hitrosti te osi. V prerezu po sliki 2 je dajalnik sestavljen v plasteh in sicer je v notranjosti obroča znana kovinska prva plast 1, ki se dotika osi, na katero je obroč nataknjen. Plast 2 je znana plast elastoferitnega nosilca in je na znane načine nanešena na kovinsko prvo plast 1. Preko plasti 2 elastoferitnega nosilca je po izumu položena zaščitna plast 3. Po prvem izvedbenem primeru plast 3 prekriva le zunanjo steno plasti 2 elastoferitnega nosilca.-3Fig. 1 is a rotary encoder, that is, a magnetic information carrier, a ring that hangs on a rotating axis and allows measuring the position, that is, the angle or speed of rotation, that is, the angular velocity of that axis. In the cross-section of Figure 2, the encoder is assembled in layers, namely, a metal first layer 1 is known inside the ring, which touches the axis to which the ring is attached. Layer 2 is a known layer of elastoferrite carrier and is applied in a known manner to a metal first layer 1. A protective layer 3 is laid over the layer 2 of the elastoferrite carrier according to the invention. According to the first embodiment, layer 3 only covers the outer wall of layer 2 of the elastoferrite carrier.

Zaščitna plast 3 je v izvedbenem primeru izdelana iz nerjavnega jekla, njena debelina je za en velikostni razred, to je reda 10x, manjša od širine magnetnih polov v elastoferitni plasti 2, kar v praksi pomeni od 50 do 100 mikrometrov. Namesto nerjavnega jekla se lahko uporabi tudi druge kovine, npr. medenino ali bronso. Zaželjeno je, da material plasti 3 ni feromagneten. Feromagnetni material je sprejemljiv le kot zelo tanka plast, ki je reda 5 -10 krat tanjša od neferomagnetne različice. Plast 3 je izdelana tako, da je kovinski trak najprej odrezan na izbrano dolžino, nato sta oba konca staknjena v obroč in sočelno zvarjena skupaj, npr. z vlakenskim laserjem. Dolžina odreza traku je izbrana tako, da je po zavaritvi traku v obroč notranji premer plasti 3 malo manjši od zunanjega premera elastoferitne plasti 2. Med montažo zaščitnega obroča plsti 3 se kovinsko plast 1 z elastoferitom plastjo 2 ohladi, zaščitno plast 3 pa segreje. Ko je zaradi termičnega raztezka notranji premer plasti 3 večji od zunanjega premera elastoferitne plasti 2, se ga natakne na elastoferitno plast 2. Po izenačitvi temperatur zaščitna plast 3 tesno objame elastoferitno plast 2. Zaščitna plast 3 je prednostno kovinska; za kovinsko plast 3 veljajo razmerja kot so navedena v opisu izvedbenega primera. Razumljivo pa je, da je zaščitna plast 3 lahko izdelana iz primernega nekovinskega materiala.In the embodiment, the protective layer 3 is made of stainless steel, its thickness is one size class, that is, about 10x smaller than the width of the magnetic poles in the elastoferrite layer 2, which in practice means from 50 to 100 micrometers. Other metals may be used instead of stainless steel, e.g. brass or bronze. It is desirable that the material of layer 3 is not ferromagnetic. The ferromagnetic material is acceptable only as a very thin layer, which is 5-10 times thinner than the non-ferromagnetic version. Layer 3 is made in such a way that the metal strip is first cut to a selected length, then the two ends are glazed into the ring and welded together, e.g. with a fiber laser. The length of the strip cut is chosen such that after welding the strip into the ring, the inner diameter of layer 3 is slightly smaller than the outer diameter of elastoferite layer 2. During assembly of the protective ring of layer 3, the metal layer 1 is cooled with elastoferite layer 2 and the protective layer 3 is warmed. When, due to thermal expansion, the inner diameter of layer 3 is larger than the outer diameter of the elastoferrite layer 2, it is applied to the elastoferrite layer 2. After equilibration of the temperatures, the protective layer 3 tightly encloses the elastoferrite layer 2. The protective layer 3 is preferably metallic; metal layer 3 is subject to the ratios as given in the embodiment description. However, it is understood that the protective layer 3 may be made of a suitable non-metallic material.

Drugi izvedbeni primer po sliki 3 je enak prvemu izvedbenemu primeru po sliki 2, le da je zaščitna plast 3 po montaži na plast 2 prekrivljena 4 preko stranskega roba plasti 2 elastoferitnega nosilca. Za prekrivljanje se uporabi običajne postopke plastičnega preoblikovanja kovin, npr. z uporabo upogibnega momenta.The second embodiment of Figure 3 is identical to the first embodiment of Figure 2, except that the protective layer 3, after mounting on layer 2, is covered 4 over the side edge of layer 2 of the elastoferrite carrier. Conventional plastic metal forming processes, e.g. using the bending moment.

Tretji izvedbeni primer po sliki 4 je enak prvemu izvedbenemu primeru po sliki 2 in drugemu izvedbenemu primeru po sliki 4, le da je zaščitna plast 3 prekrivljena preko stranske stranice • <·The third embodiment of FIG. 4 is identical to the first embodiment of FIG. 2 and the second embodiment of FIG. 4 except that the protective layer 3 is overlapped over the sidewall.

-4plasti 2 elastoferitnega nosilca in približno do polovice 9 stranske stranice prve plasti 1. V posebnem izvedbenem primeru je na poziciji polovice 9 zaščitna plast 3 privarjena na plast 1. Ta var je kontinuiran po celotnem obsegu obroča, tako da je plast 2 neprodušno zaščitena od okolja. Tudi vtem primeru se za prekrivljanje uporabi enega od običajnih postopkov plastičnega preoblikovanja kovin. Zaščitna plast 3 je na plast 1 sočelno ali prekrivno varjena prednostno z npr. vlakenskim laserjem.-4 Layers 2 of the elastoferrite support and about halfway up the side 9 of the first layer 1. In a special embodiment, at the position of the half 9, the protective layer 3 is welded to the layer 1. This weld is continuous throughout the circumference of the ring so that the layer 2 is airtight from environment. In this case, too, one of the usual methods of plastic transformation of metals is used for overlapping. The protective layer 3 is welded to the layer 1 in a side or overlaid manner, preferably by e.g. fiber laser.

Vse navedeno velja tudi za primer, ko je nosilna plast 1 nekoliko širša od elastoferitne plasti 2 in je v plasti 1 izdelan utor, v katerega je po delu svoje višine vstavljena plast 2.All of the above also applies when the carrier layer 1 is slightly wider than the elastoferrite layer 2 and a groove is formed in layer 1 into which layer 2 is inserted after part of its height.

Claims (5)

PATENTNI ZAHTEVKIPATENT APPLICATIONS 1. Magnetni dajalnik zasuka kjer je nosilec informacije elastoferitna plast, označen s tem, da je najmanj preko zunanje stene plasti (2) elastoferitnega nosilca položena zaščitna plast (3) izdelana iz neferomagnetnega materiala debeline reda 10x manjše od širine magnetnih polov v elastoferitni plasti (2) ali iz feromagnetnega materiala debeline reda 5 - 10x manjše od debeline plasti (3), izdelane iz neferomagnetnega materiala.A magnetic rotary encoder wherein the information carrier is an elastoferrite layer, characterized in that a protective layer (3) made of non-magnetic material of thickness 10x smaller than the width of the magnetic poles in the elastoferrite layer (10) is deposited at least over the outer wall of the elastoferrite carrier layer (2). 2) or of ferromagnetic material with a thickness of 5-10 times less than the thickness of the layer (3) made of non-ferromagnetic material. 2. Dajalnik po zahtevku 1, označen s tem, da je pri dajalniku zasuka plast (3) prekrivljena (4) preko stranskega roba plasti (2).Encoder according to claim 1, characterized in that, in the case of the rotary encoder, the layer (3) is covered (4) over the side edge of the layer (2). 3. Dajalnik po zahtevku 1, označen s tem, da je zaščitna plast (3) prekrivljena preko stranske stranice plasti (2) elastoferitnega nosilca in približno do polovice (9) stranske stranice prve plasti (1).Encoder according to claim 1, characterized in that the protective layer (3) is overlaid over the lateral side of the layer (2) of the elastoferite carrier and about half (9) of the lateral side of the first layer (1). 4. Dajalnik po zahtevku 3, označen s tem, da je zaščitna plast (3) na plast (1) sočelno ali prekrivno varjena, prednostno z vlakenskim laserjem.Encoder according to Claim 3, characterized in that the protective layer (3) is welded to the layer (1) face-to-face or over-welded, preferably with a fiber laser. 5. Dajalnik po zahtevku 1, označen s tem, da je na plast (2) dajalnka zasuka plast (3) pričvrščena tako, da se za montažo zaščitnega obroča plasti (3) kovinsko plast (1) z elastoferitno plastjo (2) ohladi, zaščitno plast (3) pa segreje in natakne na elastoferitno plast5. Encoder according to claim 1, characterized in that the enclosure of the encoder is rotated to the layer (2) so that the metal layer (1) is cooled by the elastoferrite layer (2) for mounting the protective ring of the layer (3). and the protective layer (3) is heated and applied to the elastoferrite layer
SI201500272A 2015-11-13 2015-11-13 A magnetic encoder with a protected elasto-ferite layer SI25094A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
SI201500272A SI25094A (en) 2015-11-13 2015-11-13 A magnetic encoder with a protected elasto-ferite layer
PCT/SI2016/000023 WO2017082831A1 (en) 2015-11-13 2016-09-20 Magnetic rotary displacement encoder with a protected elasto-ferrite layer

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SI201500272A SI25094A (en) 2015-11-13 2015-11-13 A magnetic encoder with a protected elasto-ferite layer

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Publication number Priority date Publication date Assignee Title
JP4678972B2 (en) * 2001-03-28 2011-04-27 Ｎｔｎ株式会社 Rotor for rotation sensor
FR2884314B1 (en) * 2005-04-11 2007-06-22 Hutchinson Sa MOBILE ARRAY ENCODER, DEVICE COMPRISING SUCH ENCODER AND METHOD OF MANUFACTURING SUCH ENCODER
FR2898188B1 (en) * 2006-03-06 2008-07-04 Hutchinson Sa ARRAY ENCODER, DEVICE COMPRISING SUCH ENCODER AND METHOD OF MANUFACTURING SUCH ENCODER
DE202010005645U1 (en) * 2010-06-16 2010-08-26 Ströter Antriebstechnik GmbH Encoder in the form of a plastoferrite ring and device containing such a donor
JP2015026235A (en) * 2013-07-26 2015-02-05 株式会社ワコム Electromagnetic induction sensor, coverlay member for electromagnetic induction sensor, and method of manufacturing electromagnetic induction sensor

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