GB1586807A - Method and apparatus for effecting contactless and continuous measurement of the position of a stationery or moving body of circular cross section - Google Patents

Method and apparatus for effecting contactless and continuous measurement of the position of a stationery or moving body of circular cross section Download PDF

Info

Publication number
GB1586807A
GB1586807A GB4271177A GB4271177A GB1586807A GB 1586807 A GB1586807 A GB 1586807A GB 4271177 A GB4271177 A GB 4271177A GB 4271177 A GB4271177 A GB 4271177A GB 1586807 A GB1586807 A GB 1586807A
Authority
GB
United Kingdom
Prior art keywords
sensors
spacing
output signals
difference
distance
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
Application number
GB4271177A
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.)
Fried Krupp AG
Original Assignee
Fried Krupp AG
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 Fried Krupp AG filed Critical Fried Krupp AG
Publication of GB1586807A publication Critical patent/GB1586807A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • G01B7/14—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B38/00—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
    • B21B38/10—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring roll-gap, e.g. pass indicators
    • 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
    • G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness

Description

(54) METHOD AND APPARATUS FOR EFFECTING CONTACTLESS AND CONTINUOUS MEASUREMENT OF THE POSITION OF A STATIONARY OR MOVING BODY OF CIRCULAR CROSS SECTION (71) We, FRIED. KRUPP GESELL SCHAFT MIT BESCHRANKTIiR HAF TUNG, of 103 Altendorfer Strasse, D-4300 Essen 1, Federal Republic of Germany, a German Body Corporate, do hereby declare the invention fol which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - It is known to monitor the position of a stationary body of circular cross section by sensors which move into contact with the body.In the case of a rotating body positional measurement by senors which contact the body is inexact on account of the mechanical wear experienced by the sensors and can therefore only be used to a limited extent.
It is also known to effect such monitoring by opposed stationary sensors, which do not make physical contact with the body and each of which yields electrical output signals U representative of its spacing x from the body. The characteristic relating U to x is a curve, and the sensors operate at maximum sensitivity when they are equally spaced from the body. This procedure has the disadvantage that,- whenever the axis of the body shifts from the central position between the two sensors, the sensitivity of the system is reduced. It is only possible, therefore, to detect with accuracy slight displacements of the axis of the body from the central position.
Larger displacements of the body result in serious reduction in sensitivity of the sensors.
The invention provides a contactless method of measuring the position, in relation to a reference location, of a stationary or rotating body of circular cross section by means of a pair of diametrically opposed sensors which are normally equally spaced from the body, serve to detect displacements of the body towards and away from the reference location and generate electrical output signals representing their spacing from the surface of the body, characterised in that the output signals generated by the sensors in response to such displacements are utilized not only to provide a signal representing the distance between the displaced body and the reference location but also to effect automatic movement of the sensors to a position in which they are again equally spaced from the body.
Since the sensors always operate at equal spacing from the body no limit is set to the extent of displacement of the body which can be accurately measured.
The invention includes apparatus for contactless measurement of variations in position of a stationary or rotating body of circular cross section comprising, in combination with said body, a pair of diametrically opposed sensors, which are normally equally spaced from the surface of the body and provide electrical output signals representative of their spacing from the body, a follow up mechanism which operates in response to a difference between the output signals from the sensors arising from displacement of the body towards one of the sensors to move the sensors to a position in which they are again equally spaced from the body and means also responsive to such difference for affording an electrical signal indicative of the distance between the body and a reference location.
Certain embodiments of the invention will now be described with reference to the accompanying diagrammatic drawings, in which: Fig. 1 is an explanatory diagram, Fig. 2 is a graph, Fig. 3 illustrates application of the invention to measurement of the gap between a pair of rolls, Fig. 4 shows the electrical system employed in one embodiment of the invention, and Fig. 5 shows a more elaborate apparatus for measuring displacements of a body with respect to two mutually perpendicular reference surfaces.
As shown in Fig. 1 diametrically opposed sensors 1, 2 are spaced at distances x" X2 from the surface of a cylindrical body 0 of radius r. The sensors 1, 2 yield respective electrical output signals U1, U2 dependent on the spacing between the sensors and the body 0.
These signals vary in response to vertical displacements of the axis of the body AXA or EX, and thus afford an indication of the position of said axis.
As will be seen from Fig. 2, the graphs relating U1 to xl and U to x are curves and the sensitivity of the system is a maximum at the point of intersection of these curves, in which the sensors are equally spaced from the body and the output signal U10 of the sensor 1 is equal to the output signal U, of the sensor 2. In the event of a deviation AXA or ExlB in the position of the axis of the body 0 in the vertical direction as seen in Fig. 1 differential output signals !AUA = U1 - U2, or AUB = U2 - UL are produced which are representative of the new position of the body.
Fig. 4 shows apparatus for measuring dis placements of the axis of a cylindrical body O in the vertical direction x. As in Fig. 1, this is effected by a pair of diametrically opposed sensors 1, 2 equally spaced at opti mum spacing from the surface of the body 0 and mounted in a carrier 5. The difference AUt between the output signals U1, U2 of the sensors is derived by an electronic differ ence former 6 and fed to a follow up mech anism 7 and to an electronic device 9. When there is a difference between the output sig nals the mechanism 7 readjusts the position of the carrier to return the sensors 1, 2 to the position of equal spacing from the body O.The displacement Ax of the carrier 5 from its datum spacing Sx from a horizontal reference surface 10 is recorded in a distance measurement device 8. A signal representing the distance S = Sx + Ax between the body 0 and the reference surface 10 is pro vided immediately at the output of the elec- tronic device 9. The carrier 5 may be re moved from the body 0 in the direction of the arrow 11.
Fig. 5 shows apparatus for affording twodimensional position measurement of a cylindrical body 0 of rotation in the vertical and horizontal directions x, y. A carrier Sb carrying orthogonally disposed pairs of sensors 1, 2 and 3, 4 is movable in the horizontal direction y in another carrier 5a, which is displaceable in the vertical direction x along a vertical reference surface 10b, in relation to a horizontal reference surface 10a. The sensors of both pairs are at equal spacing from the body.
Signals AU, AU, representing the differences between the output signals of the sensors 1, 2 and 3, 4 respectively and resulting from vertical and horizontal displacements of the body 0 are formed in an electronic difference former 6 and are fed respectively to follow up mechanisms 7a, 7b for the carriers 5a and 5b, which shift the carriers as necessary to maintain the pairs of sensors 1, 2 and 3, 4 at equal spacing from the body 0. Both difference signals are fed to an electronic device 9.Distance measuring devices 8a, 8b record respectively vertical displacements Ax of the carrier 5a from its datum spacing Sx' from the reference surface 10a and horizontal displacements Ay of the carrier 5b from its datum spacing Sy' from the reference surface 10b. Signals representing the vertical distance Sx = S.x' + Ax of the body from the reference surface 10a and the horizontal distance Sy = Sy' + Ay of the body from the reference surface 10b are provided at the output of the electronic device 9.
Figure 3 shows apparatus for measuring the gap So between a pair of rolls 21, 22 mounted in bearings 23 and having stepped reference surfaces 25. A pair of sensors 24 is disposed diametrically with respect to each surface 25, the sensors being normally at equal spacing from the surface. As before, upon variation in the position of a roll with respect to a reference surface 26 which causes a change in the gap Si or S2 at the left or the right, the sensors 24 are readjusted in position as necessary to return them to equal spacing with respect to their respective surface 25 and an output signal representing the actual value of the roll gap is provided.
WHAT WE CLAIM IS: - 1. A contactless method of measuring the position, in relation to a reference location, of a stationary or rotating body of circular cross section by means of a pair of diametrically opposed sensors, which are normally equaly spaced from the body, serve to detect displacements of the body towards and away from the reference location and generate electrical output signals representing their spacing from the surface of the body, characterised in that the output signals generated by the sensors in response to such displacements are utilized not only to provide a signal representing the distance between the displaced body and the reference location but also to effect automatic movement of the sensors to a position in which they are again equally spaced from the body.
2. Apparatus for contactless measurement of variations in position of a stationary or rotating body of circular cross section comprising, in combination with said body, a pair of diametrically opposed sensors, which are normally equally spaced from the surface of the body and provide electrical output signals representative of their spacing from the body, a follow up mechanism which operates in response to a difference between the output signals from the sensors arising from displacement of the body towards one
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. sensors 1, 2 are spaced at distances x" X2 from the surface of a cylindrical body 0 of radius r. The sensors 1, 2 yield respective electrical output signals U1, U2 dependent on the spacing between the sensors and the body 0. These signals vary in response to vertical displacements of the axis of the body AXA or EX, and thus afford an indication of the position of said axis. As will be seen from Fig. 2, the graphs relating U1 to xl and U to x are curves and the sensitivity of the system is a maximum at the point of intersection of these curves, in which the sensors are equally spaced from the body and the output signal U10 of the sensor 1 is equal to the output signal U, of the sensor 2. In the event of a deviation AXA or ExlB in the position of the axis of the body 0 in the vertical direction as seen in Fig. 1 differential output signals !AUA = U1 - U2, or AUB = U2 - UL are produced which are representative of the new position of the body. Fig. 4 shows apparatus for measuring dis placements of the axis of a cylindrical body O in the vertical direction x. As in Fig. 1, this is effected by a pair of diametrically opposed sensors 1, 2 equally spaced at opti mum spacing from the surface of the body 0 and mounted in a carrier 5. The difference AUt between the output signals U1, U2 of the sensors is derived by an electronic differ ence former 6 and fed to a follow up mech anism 7 and to an electronic device 9. When there is a difference between the output sig nals the mechanism 7 readjusts the position of the carrier to return the sensors 1, 2 to the position of equal spacing from the body O.The displacement Ax of the carrier 5 from its datum spacing Sx from a horizontal reference surface 10 is recorded in a distance measurement device 8. A signal representing the distance S = Sx + Ax between the body 0 and the reference surface 10 is pro vided immediately at the output of the elec- tronic device 9. The carrier 5 may be re moved from the body 0 in the direction of the arrow 11. Fig. 5 shows apparatus for affording twodimensional position measurement of a cylindrical body 0 of rotation in the vertical and horizontal directions x, y. A carrier Sb carrying orthogonally disposed pairs of sensors 1, 2 and 3, 4 is movable in the horizontal direction y in another carrier 5a, which is displaceable in the vertical direction x along a vertical reference surface 10b, in relation to a horizontal reference surface 10a. The sensors of both pairs are at equal spacing from the body. Signals AU, AU, representing the differences between the output signals of the sensors 1, 2 and 3, 4 respectively and resulting from vertical and horizontal displacements of the body 0 are formed in an electronic difference former 6 and are fed respectively to follow up mechanisms 7a, 7b for the carriers 5a and 5b, which shift the carriers as necessary to maintain the pairs of sensors 1, 2 and 3, 4 at equal spacing from the body 0. Both difference signals are fed to an electronic device 9.Distance measuring devices 8a, 8b record respectively vertical displacements Ax of the carrier 5a from its datum spacing Sx' from the reference surface 10a and horizontal displacements Ay of the carrier 5b from its datum spacing Sy' from the reference surface 10b. Signals representing the vertical distance Sx = S.x' + Ax of the body from the reference surface 10a and the horizontal distance Sy = Sy' + Ay of the body from the reference surface 10b are provided at the output of the electronic device 9. Figure 3 shows apparatus for measuring the gap So between a pair of rolls 21, 22 mounted in bearings 23 and having stepped reference surfaces 25. A pair of sensors 24 is disposed diametrically with respect to each surface 25, the sensors being normally at equal spacing from the surface. As before, upon variation in the position of a roll with respect to a reference surface 26 which causes a change in the gap Si or S2 at the left or the right, the sensors 24 are readjusted in position as necessary to return them to equal spacing with respect to their respective surface 25 and an output signal representing the actual value of the roll gap is provided. WHAT WE CLAIM IS: -
1. A contactless method of measuring the position, in relation to a reference location, of a stationary or rotating body of circular cross section by means of a pair of diametrically opposed sensors, which are normally equaly spaced from the body, serve to detect displacements of the body towards and away from the reference location and generate electrical output signals representing their spacing from the surface of the body, characterised in that the output signals generated by the sensors in response to such displacements are utilized not only to provide a signal representing the distance between the displaced body and the reference location but also to effect automatic movement of the sensors to a position in which they are again equally spaced from the body.
2. Apparatus for contactless measurement of variations in position of a stationary or rotating body of circular cross section comprising, in combination with said body, a pair of diametrically opposed sensors, which are normally equally spaced from the surface of the body and provide electrical output signals representative of their spacing from the body, a follow up mechanism which operates in response to a difference between the output signals from the sensors arising from displacement of the body towards one
of the sensors to move the sensors to a position in which they are again equally spaced from the body and means also responsive to such difference for affording an electrical signal indicative of the distance between the body and a reference location.
3. Apparatus according to claim 2, comprising an electronic difference former connected to the follow up mechanism for producing and applying to the follow up mechanism an output signal representative of the difference between the output signals of the sensors, a device for measuring the distance between a carrier for the sensor and a reference surface perpendicular to the diameter of the body on which the sensors are disposed, and an electronic device connected to the difference former and to the measuring device which affords an output signal representing the distance between the body and the reference surface.
4. Apparatus according to claim 3, which includes two orthogonally disposed pairs of sensors, each of which is disposed on a diameter of the object with the sensors of the pair equally spaced from the surface of the body, the pairs of sensors being mounted on carriers movable in mutually perpendicular directions, and wherein the difference former produces output signals representing the difference between the output signals of each pair of sensors and applies these signals to separate follow up mechanisms for adjusting the respective carriers to return the sensors to positions of equal spacing from the body, the apparatus including separate distance measuring devices for measuring the distances between the carriages and mutually perpendicular reference surfaces and the electronic device affording output signals representing the distances between the body and the two reference surfaces.
GB4271177A 1976-10-14 1977-10-13 Method and apparatus for effecting contactless and continuous measurement of the position of a stationery or moving body of circular cross section Expired GB1586807A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19762646328 DE2646328A1 (en) 1976-10-14 1976-10-14 CONTACTLESS POSITION MEASUREMENT OF STANDING OR MOVING ROTATING BODY

Publications (1)

Publication Number Publication Date
GB1586807A true GB1586807A (en) 1981-03-25

Family

ID=5990412

Family Applications (1)

Application Number Title Priority Date Filing Date
GB4271177A Expired GB1586807A (en) 1976-10-14 1977-10-13 Method and apparatus for effecting contactless and continuous measurement of the position of a stationery or moving body of circular cross section

Country Status (2)

Country Link
DE (1) DE2646328A1 (en)
GB (1) GB1586807A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0124731A1 (en) * 1983-04-07 1984-11-14 H.F. Stollberg Maschinenfabrik GmbH Apparatus for the contactless measurement of the position of a first body in relation to a second body
US9764368B2 (en) 2011-09-23 2017-09-19 Sms Group Gmbh Rolling mill and rolling method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4319898A1 (en) * 1993-06-16 1994-12-22 Wyrwoll Gmbh Device for the non-contact testing and/or measurement of rotationally symmetrical workpieces
WO2013041083A2 (en) * 2011-09-23 2013-03-28 Sms Meer Gmbh Rolling mill and rolling method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0124731A1 (en) * 1983-04-07 1984-11-14 H.F. Stollberg Maschinenfabrik GmbH Apparatus for the contactless measurement of the position of a first body in relation to a second body
US9764368B2 (en) 2011-09-23 2017-09-19 Sms Group Gmbh Rolling mill and rolling method
US10654084B2 (en) 2011-09-23 2020-05-19 Sms Group Gmbh Rolling mill and rolling method

Also Published As

Publication number Publication date
DE2646328A1 (en) 1978-04-20

Similar Documents

Publication Publication Date Title
US5959295A (en) Timing device and method for positioning non-linear machine parts
US3428817A (en) Length measurer with plurality of photocells which are sequentially gated
US3708681A (en) Position and velocity sensor
GB1364768A (en) Measuring the position of an operating agency in a machine
KR920702886A (en) Apparatus and method for measuring length of moving object
SU1025331A3 (en) Device for controlling thickness of fibrous material
ES447690A1 (en) Gauging surfaces by remotely tracking multiple images
KR870010379A (en) Sensor for independent linear size measuring device
GB1136262A (en) Improvements in or relating to the manufacture of sheet material in ribbon form
US2914756A (en) Measuring apparatus comprising a graduated scale
GB1586807A (en) Method and apparatus for effecting contactless and continuous measurement of the position of a stationery or moving body of circular cross section
EP0169379B1 (en) A measuring device for a figure
JPH0511561B2 (en)
GB1319531A (en) Arrangement for producing a signal curve
US5327082A (en) On line electromagnetic web thickness measuring apparatus incorporating a servomechanism with optical distance measuring
GB1408078A (en) Method of controlling a motion of a land vehicle
JPS62240805A (en) Length measuring apparatus
JPH07270436A (en) Length measuring apparatus for moving object
US3531207A (en) Digital spectral line identifier
GB1329337A (en) Apparatus for scanning and evaluating markings
JPH0592216A (en) Coiling/uncoiling device
FR2267885A1 (en) Printing machine adjusting mechanism - has control transducer responsive to paper thickness detector feelers
JPS61250562A (en) Apparatus for detecting motion quantity
JPS57124561A (en) Measuring device for roll alignment
US3538333A (en) Electro-optical displacement amplifier

Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee