EP1982148A2 - Unité de guidage linéaire équipée d'un système de mesure de longueur - Google Patents

Unité de guidage linéaire équipée d'un système de mesure de longueur

Info

Publication number
EP1982148A2
EP1982148A2 EP06841352A EP06841352A EP1982148A2 EP 1982148 A2 EP1982148 A2 EP 1982148A2 EP 06841352 A EP06841352 A EP 06841352A EP 06841352 A EP06841352 A EP 06841352A EP 1982148 A2 EP1982148 A2 EP 1982148A2
Authority
EP
European Patent Office
Prior art keywords
linear guide
guide unit
unit according
material measure
clamping sleeve
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.)
Withdrawn
Application number
EP06841352A
Other languages
German (de)
English (en)
Inventor
Dietmar Rudy
Martin Menges
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.)
Schaeffler Technologies AG and Co KG
Original Assignee
Schaeffler KG
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 Schaeffler KG filed Critical Schaeffler KG
Publication of EP1982148A2 publication Critical patent/EP1982148A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C29/00—Bearings for parts moving only linearly
    • F16C29/04—Ball or roller bearings
    • F16C29/06—Ball or roller bearings in which the rolling bodies circulate partly without carrying load
    • F16C29/0633—Ball or roller bearings in which the rolling bodies circulate partly without carrying load with a bearing body defining a U-shaped carriage, i.e. surrounding a guide rail or track on three sides
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C41/00—Other accessories, e.g. devices integrated in the bearing not relating to the bearing function as such
    • F16C41/007—Encoders, e.g. parts with a plurality of alternating magnetic poles
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/003—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring position, not involving coordinate determination
    • 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
    • G01D5/204—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 by influencing the mutual induction between two or more coils
    • G01D5/2046—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 by influencing the mutual induction between two or more coils by a movable ferromagnetic element, e.g. a core

Definitions

  • the present invention relates to a linear guide unit provided with a length measuring system.
  • Such linear guide units are used for example in machine tool or in transport devices of assembly lines or in wood processing.
  • the length measuring systems enable a highly accurate positioning of the carriages at predetermined positions.
  • a linear bearing with a device for measuring wherein a guide carriage is arranged longitudinally displaceable on a guide rail.
  • the carriage is provided with a measuring head on the front side.
  • the guide rail is provided on its upper side with a groove into which a material measure is inserted.
  • the material measure is formed here in one piece with a cover strip, which is held non-positively in the groove of the guide rail.
  • the material measure can be glued to the ribbon. If a change in the material measure is required, this can only be achieved by replacing the material measure with the masking tape.
  • the scale or the material measure is adhered to the guide rail as delivered. In this case, a replacement of a material measure without replacement of the guide rail is difficult.
  • Object of the present invention is to provide a linear guide unit according to the features of the preamble of claim 1, in which an exchange of the material measure is easily possible. According to the invention, this object is achieved in that the material measure in a the Measuring standard carrying hollow body is arranged, which is arranged at a distance from the guide rail and mounted at its ends.
  • the invention offers several advantages. First, it is ensured that the material measure can be replaced independently of the guide rail. For a change of the material measure, the guide rail need not be solved nor a masking tape to be removed. The material measure to be exchanged only needs to be removed from the hollow body, for example a pipe, and replaced by another material measure.
  • linear guide units can be realized with very long travel distances, without the need for additional supports for the material measure to avoid unwanted bending of the material measure; because the material measure only needs to be introduced into the hollow body, in which it is then supported evenly over its entire longitudinal extent.
  • a lubricant that reduces the sliding friction in contact of the material measure with the inner wall of the hollow body.
  • the material measure can be arranged within the clearance of the linear guide unit.
  • the width and height of the clearance profile of linear guide units are described in DIN 645-1 and -2 in the form of a table in which standardized sizes of the guide carriage are specified.
  • the manufacturers of linear guide units are held to this DIN.
  • the advantage of normalization is that for planning of assembly lines, for example, resorted to this standard and the required space requirements for the linear guide of objects can be well planned.
  • the integration of the material measure within the clearance gauge thus restricts the applicability of this standard in any way.
  • the choice of the known length measuring systems is not limited by the fact that the guide rail is usually made of steel. If the length measuring system is based on the inductive measuring principle, this measuring principle could not be used without special additional measures; because the usually formed of magnetic steel guide rail would complicate a perfect measurement at least. In contrast, in the case of the solution according to the invention, it is sufficient in this case to form the hollow body from a suitable material, for example plastic or non-magnetic steel.
  • clamping sleeve may be mounted at its two ends in each case on a bearing block and acted upon between these bearing blocks with a tensile stress.
  • the tension supports a perfect linear arrangement of the material measure, because it avoids sagging or bending of the scale carrying the clamping sleeve.
  • the tension can be applied by means of a tensioning device.
  • the clamping device on a clamping nut which is screwed onto a provided at one end of the clamping sleeve screw thread.
  • This screw thread can be mounted directly on the jacket of the clamping sleeve, but it can also be formed on a separate threaded sleeve, which is placed on the one end of the clamping sleeve and fastened thereto - eg. Welded - is.
  • the hollow body formed as a tube or clamping sleeve is mounted at its two ends in each case on a bearing block, which may be formed, for example, by a prism.
  • the above-mentioned clamping nut can be axially supported on one of these bearing blocks in order to transmit the axial tensile force of the clamped clamping sleeve to the one bearing block.
  • the clamping sleeve is then supported at its other end also axially on the other bearing block.
  • the material measure may comprise, for example, a stainless steel tube which is filled with a plurality of chromium-nickel elements arranged one behind the other.
  • the measuring head may be, for example, an aluminum casting containing a coil assembly and electronics.
  • the measuring head can surround the tubular measuring scale annularly.
  • the measuring head can be provided with a multiplicity of receiver coil sets. Each set may consist of four identical angles arranged at intervals of one pitch. Because of this distance, each coil is positioned in one set over an identical part of an adjacent chromium-nickel element. All coils of a set are connected in series.
  • the drive coil Due to the chromium-nickel element in the scale, the magnetic permeability of the scale changes periodically over a pitch.
  • the voltage induced in each group of probe coils changes according to the relative positions of the coils to the underlying chromium-nickel elements.
  • the coils are spaced so that when one group of coils is at the maximum, another group that is one-half of the chromium-nickel element pitch is at the minimum.
  • These coil pairs are differentially combined to produce signals that change with the shift. These combined signals are phase-shifted by the electronic circuits in the measuring head. postponed. The signals are added and filtered. The result is an output signal whose phase changes as the probe moves along the scale.
  • the inventively provided hollow body is formed of non-magnetic material. In this way it is ensured that magnetic field lines, as they occur in the measuring principle described above, are not disturbed.
  • FIG. 1 shows a linear guide unit according to the invention in perspective
  • Figure 2 is a schematic representation of the linear guide unit according to the invention in partial longitudinal section.
  • the linear guide unit according to the invention shown in FIGS. 1 and 2 has a guide carriage 2 guided longitudinally displaceably on a guide rail 1.
  • rolling elements not further illustrated here roll on raceways of the guide rail and the guide carriage under load. These tracks limit a load channel.
  • the rolling elements run in endless WälzSystemkanälen, each WälzSystem- channel having the already mentioned load channel, a return channel, and two the return passage and the load channel endlessly connecting deflection channels.
  • the deflection channels and the return channels are completely provided in the guide carriage 2.
  • the carriage 2 engages with its two legs 5, the guide rail 1, wherein the two legs 5 are connected to each other via a back 6.
  • On the one leg 5 is a through hole. 7 formed, through which a clamping sleeve 12 is passed.
  • This passage opening 7 is in the present case designed as a bore 8.
  • This leg 5 is provided to the one with only a dashed line indicated recess 9, in which a measuring head 3 of a length measuring device is used.
  • the clamping sleeve 12 is mounted at its two ends in each case on a bearing block 10, 1 1, both of which are designed as a fixed bearing.
  • the guide rail 1 has seen in cross-section on a prism-shaped profile.
  • the bearing blocks 10, 1 1 are provided with a corresponding prismatic profile, so that the bearing blocks 10, 1 1 are properly aligned with the guide rail 1.
  • the proper alignment of the bearing blocks 10, 1 1 ensures that the clamping sleeve 12 is arranged properly parallel to the guide rail 1.
  • the linear guide unit according to the invention furthermore comprises the length measuring system, which has a measuring head 3 and a measuring graduation 4 clearly illustrated in FIG.
  • This length measuring system works on the induction principle.
  • This material measure 4 comprises a stainless steel tube in which a plurality of chromium-nickel elements 4a arranged at a predetermined distance are arranged.
  • the measuring head 3 is equipped so that 3 sinusoidal signals are generated in a relative displacement between the material measure 4 and the measuring head, which are used for an evaluation.
  • These measuring graduations 4 can be accommodated in a favorable manner within the clearance gauge of the guide carriage 2 and thus also within the clearance profile of the linear guidance unit.
  • the measuring graduation 4 is arranged in the clamping sleeve 12 formed of non-magnetic material.
  • the material measure 4 is supported over its entire extension to the clamping sleeve 12 and protected therein.
  • the clamping sleeve 12 is fixed at one end to the one bearing block 1 1. For this purpose, this end is provided with a holding sleeve 13, which is axially supported on the bearing block 1 1.
  • a threaded sleeve 14 is welded on the other end of the clamping sleeve 12.
  • a clamping nut 15 is screwed, which is axially supported on the bearing block 10. Under a screwing movement of the clamping nut 15, an axial tensile stress can be applied to the clamping sleeve 12, so that a sagging of the clamping sleeve 12 is excluded in any case.
  • a tube can be used, which is fixed to the one bearing block 1 1 as in the case of the clamping sleeve.
  • the other end of this tube is mounted on the bearing block 10 in the manner of a floating bearing.
  • Such pipes can be used if bending of the pipe, for example due to reduced pipe length or due to sufficient pipe rigidity can be excluded.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Transmission And Conversion Of Sensor Element Output (AREA)
  • Length Measuring Devices With Unspecified Measuring Means (AREA)
  • A Measuring Device Byusing Mechanical Method (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Bearings For Parts Moving Linearly (AREA)

Abstract

La présente invention concerne une unité de guidage linéaire comprenant un chariot de guidage (2) monté mobile en direction longitudinale sur un rail de guidage (1), ainsi qu'un système de mesure de longueur dont la tête de mesure (3) coopère avec une mesure matérialisée (4) montée parallèlement au rail de guidage (1). Cette mesure matérialisée (4) se trouve dans un corps creux qui porte la mesure matérialisée (4), qui est monté à distance du rail de guidage (1) et qui est supporté à ses extrémités.
EP06841352A 2006-01-27 2006-12-13 Unité de guidage linéaire équipée d'un système de mesure de longueur Withdrawn EP1982148A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102006003980A DE102006003980A1 (de) 2006-01-27 2006-01-27 Linearführungseinheit mit Längenmesssystem
PCT/EP2006/069673 WO2007085329A2 (fr) 2006-01-27 2006-12-13 Unité de guidage linéaire équipée d'un système de mesure de longueur

Publications (1)

Publication Number Publication Date
EP1982148A2 true EP1982148A2 (fr) 2008-10-22

Family

ID=38229297

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06841352A Withdrawn EP1982148A2 (fr) 2006-01-27 2006-12-13 Unité de guidage linéaire équipée d'un système de mesure de longueur

Country Status (6)

Country Link
US (1) US7895766B2 (fr)
EP (1) EP1982148A2 (fr)
JP (1) JP2009524804A (fr)
CN (1) CN101336362B (fr)
DE (1) DE102006003980A1 (fr)
WO (1) WO2007085329A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105526897A (zh) * 2016-01-18 2016-04-27 中国石油化工股份有限公司 一种修井作业用管杆长度测量装置

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DE102005021345A1 (de) * 2005-05-04 2006-11-09 Schaeffler Kg Linearführungseinheit mit Längenmesssystem
GB0807088D0 (en) * 2008-04-18 2008-05-21 Eley Metrology Ltd Positioning apparatus
GB0902547D0 (en) * 2009-02-16 2009-04-01 Renishaw Plc Encoder scale member and method for mounting
DE102011079464A1 (de) * 2011-07-20 2013-01-24 Dr. Johannes Heidenhain Gmbh Längenmesseinrichtung
CN104110247B (zh) * 2013-04-19 2018-09-28 中国石油集团长城钻探工程有限公司 至少检测三维阵列感应测井仪径向线圈中心直线度的平台
CN104110248B (zh) * 2013-04-19 2018-10-19 中国石油集团长城钻探工程有限公司 至少检测阵列感应测井仪探头短节整体直线度的平台
CN104110246B (zh) * 2013-04-19 2018-09-28 中国石油集团长城钻探工程有限公司 至少检测三维阵列感应测井仪轴向线圈同心度的平台
JP6361189B2 (ja) 2014-03-14 2018-07-25 Thk株式会社 運動案内装置
JP1528331S (fr) * 2014-09-11 2015-07-13
CN104858904B (zh) * 2014-12-06 2016-07-13 重庆溯联汽车零部件有限公司 尼龙管切割夹具
GB2542843B (en) * 2015-10-01 2020-02-05 Newall Measurement Syst Ltd Inductive position detector
JP6895332B2 (ja) * 2017-07-05 2021-06-30 株式会社ミツトヨ リニアスケール
DE102018128023A1 (de) * 2018-11-09 2020-05-14 Schaeffler Technologies AG & Co. KG Linearführung
DE102021103515A1 (de) * 2021-02-15 2022-08-18 Balluff Gmbh Induktiver Wegsensor mit verschiebbarem Messkopf
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CN105526897A (zh) * 2016-01-18 2016-04-27 中国石油化工股份有限公司 一种修井作业用管杆长度测量装置

Also Published As

Publication number Publication date
JP2009524804A (ja) 2009-07-02
CN101336362A (zh) 2008-12-31
WO2007085329A3 (fr) 2007-09-13
CN101336362B (zh) 2011-01-19
WO2007085329A2 (fr) 2007-08-02
US7895766B2 (en) 2011-03-01
US20100175272A1 (en) 2010-07-15
DE102006003980A1 (de) 2007-08-02

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