US3714806A - Drift corrector for transducers - Google Patents

Drift corrector for transducers Download PDF

Info

Publication number
US3714806A
US3714806A US00173436A US3714806DA US3714806A US 3714806 A US3714806 A US 3714806A US 00173436 A US00173436 A US 00173436A US 3714806D A US3714806D A US 3714806DA US 3714806 A US3714806 A US 3714806A
Authority
US
United States
Prior art keywords
integrator
input
output
circuit
amplifier
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 - Lifetime
Application number
US00173436A
Other languages
English (en)
Inventor
E Berkey
E Keener
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.)
United States Steel Corp
Original Assignee
Steel 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 Steel Corp filed Critical Steel Corp
Application granted granted Critical
Publication of US3714806A publication Critical patent/US3714806A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
    • G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
    • G01L1/225—Measuring circuits therefor
    • 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
    • B21B38/08—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-force
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
    • G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
    • G01L1/2268—Arrangements for correcting or for compensating unwanted effects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/0061—Force sensors associated with industrial machines or actuators
    • G01L5/0066—Calibration arrangements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/0061—Force sensors associated with industrial machines or actuators
    • G01L5/0076—Force sensors associated with manufacturing machines

Definitions

  • ABSTRACT Apparatus for measuring the roll separating force produced by a workpiece includes a strain gage bridge, and an amplifier having a first input connected to the output of the bridge, a second input and an output.
  • a first circuit including a polarity reversal means and an integrator connected in series is arranged between the output and second input of the amplifier.
  • the integrator has an input connected to the output of the amplifier, an output connected to the second input of the amplifier, and a control connection.
  • a second circuit between the control connection and the first circuit on the input side of the integrator includes switch means operable when there is no workpiece in the mill to provide a signal to the control connection to cause the integrator to be in its operative mode and operable when there is a workpiece in the mill to provide a signal to the control connection to cause the integrator to be in its hold mode.
  • This provides a signal to the amplifier from the integrator which is equal and opposite to the voltage from the bridge when there is no workpiece in the mill which voltage remains constant when the workpiece is in the mill.
  • This invention relates to a drift corrector for transducers and more particularly to correcting drift associated with a resistance strain gage for measuring roll separating forces on a metal rolling mill.
  • Rolling mills are used to reduce steel ingots or the like to slabs, plates, strip, or other shapes. ln a slabbing mill the ingot is reduced to a slab of the desired width and thickness. This is usually done by passing the ingot through a rolling mill in several passes. The fewer the number of passes the greater the production. However, the reduction per pass is limited by the rolling mill design and drive motor capacities. It is desirable to adjust the mill to obtain maximum reduction per pass without exceeding the safe roll separating force.
  • FIGURE is a schematic drawing of our invention as incorporated in a rolling mill.
  • reference numeral 2 indicates a roll housing having work rolls 4 rotatably supported therein with a screw down 6 for varying the roll pass and hence the roll pressure as a workpiece W passes therethrough.
  • the parts so far described are conventional and form no part of the present invention.
  • a strain gage bridge 8 is installed on one leg of the housing 2.
  • Voltage power supply 10 supplies the voltage across the bridge 8.
  • a balance control 12 is provided across the power supply 10. Flow of power to the bridge 8 is controlled by a switch 14.
  • Strain on the housing 2 caused by a separating force on the rolls 4 during the rolling operation causes the housing 2 to stretch. This stretch of the housing causes the resistance of the strain gage bridge 8 to change proportional to the stretch.
  • the resistance change in the bridge 8 causes the output voltage of the bridge to change proportional to the roll separating force.
  • Balance control 12 is used to adjust the bridge output to zero when no force load is present. Stretch in the housing 2 due to temperature also causes the output voltage of the bridge 8 to change. This voltage output change is the drift referred to above.
  • a differential amplifier 16 is connected to the output of the bridge 8. This is preferably an Electronic Associates, Inc. (EAl) Type 6.0777 having a gain of 1,000.
  • the output of amplifier 16 is connected to an amplifier 18 which is preferably an EAl Type 6.0864.
  • Output 20 of the amplifier 18 is connected to a force meter 22 and/or a force recorder 24.
  • the output 20 is also connected to an amplifier 26 which acts to reverse the polarity and preferably has a gain of one.
  • the output of amplifier 26 is connected through a potentiometer 28 to an integrator or amplifier 30 which is preferably an EAl Type 12.1780.
  • the output 20 is also connected to comparators 32 and 34 which are preferably EAl Type 0.40.0729.
  • An input voltage is supplied to comparators 32 and 34 through potentiometers 36 and 38, respectively.
  • the comparators 32 and 34 are connected to the inputs of a logical NAND gate 40 which is preferably a Texas lnstrument Type SN-741ON.
  • the comparator 34 is optional and, if omitted, the gate 40 is also omitted.
  • the output of gate 40 or the output of comparator 32, if comparator 34 and gate 40 are omitted, is connected through line 42 as a control connection input to integrator 30.
  • the output of integrator 30 is connected through line 44 as an input to amplifier 18.
  • a normally open switch 46 is connected in parallel with potentiometer 28 and a normally closed switch 48 is connected in line 42 for simultaneous operation.
  • the switch 48 is also connectable to a voltage supply 50 which preferably is of 5 volts.
  • the setting of the potentiometer 28 is adjusted to obtain the desired rate of change of the drift compensation. Normally when the rate of change in drift is relatively slow the adjustment for drift is also made relatively slow and when the rate of change of drift is relatively fast the adjustment will be made relatively fast. It will be understood that the potentiometer 28 may be omitted when it is not desired to vary the speed of drift compensation. Assuming that the comparator 34 and gate 40 have been omitted the potentiometer 36 will be adjusted to provide a voltage to comparator 32 that is above the normal extraneous noise signals and below the lowest expected force signal level. ln one particular embodiment this is normally 1 volt. With the switch 14 closed the gage is ready for operation.
  • the signal from amplifier 18 will be greater than the voltage of potentiometer 36. This will show on meter 22 and recorder 24 and in order to quickly balance the system, switch 46 is closed and switch 48 moved to open line 42 and to connect integrator 30 to voltage control input supply 50. After the system is balanced the switches 46 and 48 are returned to their original position.
  • the voltage generated by bridge 8 is proportional to the combined strain due to drift and roll pressure and also the output from amplifier 18 goes positive. This causes the signal from comparator 32 to put the integrator 30 in the hold mode so that the signal on line 44 remains constant and equal and opposite to the drift force.
  • the signal from amplifier 18 appears on meter 22 and recorder 24 as a measurement of the rolling force since the voltage proportional to drift is subtracted from the total voltage.
  • the signal from comparator 32 reverses polarity and causes integrator 30 to be in its operate mode.
  • the voltage on line 44 will change until it balances the output from amplifier 16.
  • the comparator 34 and gate 40 are used only when there are extraneous negative signals present which may cause error in the recorded force signal.
  • the potentiometer 38 is adjusted to give a negative voltage greater than any negative voltage from an extraneous signal.
  • the integrator 30 will be in the operate mode if the output of amplifier 18 is less than the threshold level set on either potentiometer 36 and 38. In either case this causes the output voltage of gate 40 to be positive thus putting the integrator 30 in its operate mode. 7
  • the amplifier 16 may be omitted if the generated voltage is of sufficient magnitude for operating the circuit. The polarity of the various voltages may be reversed from that described. It is necessary that the generated voltage signal to amplifier 18 be of opposite polarity to that of the voltage from integrator 30.
  • the sole purpose of amplifier 26 is to act as a voltage polarity reversal means and it may be located anywhere in the circuit between the output of amplifier 18 and the input of amplifier 18.
  • the comparators 32 and 34 act as switch means to control the operation of integrator 30.
  • Apparatus for measuring a desired characteristic comprising means for generating a voltage signal having a component proportional to the desired characteristic and a component proportional to drift, an amplifier having a first input connected to the output of said generating means, a second input and an output, a first circuit including a voltage polarity reversal means and an integrator connected in series between the output and second input of said amplifier, said integrator having an input connected to the output of said amplifier, an output connected to the second input of said amplifier and a control connection, and a second circuit between the first circuit on the input side of said integrator and said control connection, said second circuit including switch means operable when there is no voltage component proportional to the desired characteristic being generated to provide a signal to said control connection to cause said integrator to be in its operate mode and operable when there is such a voltage being generated to provide a signal to said control connection to cause said integrator to be in its hold mode whereby the output of said amplifier is proportional only to the desired characteristic when the component proportional to the desired characteristic is present,
  • Apparatus according to claim 1 including a potentiometer in said first circuit connected to the input of said integrator to control the speed of drift compensation.
  • Apparatus according to claim 2 including a bypass circuit around said potentiometer having a normally open switch therein, a normally closed switch in said second circuit, and a power source connectable to said control connection when said normally closed switch is opened.
  • said switch means includes a comparator, and means for supplying a desired voltage to said comparator.
  • Apparatus according to claim 4 including a potentiometer in said first circuit connected to theinput of said integrator to control the speed of drift compensa tion.
  • Apparatus according to claim 5 including a by pass circuit around said potentiometer having anorrnally open switch therein, a normally closed switch in said second circuit, and a power source connectable to said control connection when said normally closed switch is opened.
  • said second circuit includes a second comparator connected in parallel with said first named comparator, means for supplying a desired voltage to said second comparator of opposite polarity to the voltage supplied to said first comparator, and a gate connected to the outputs of said comparators.
  • Apparatus for measuring the roll separating force produced by a workpiece passing between work rolls mounted in a housing which comprises a strain gage bridge mounted on said housing, an amplifier having a first input connected to the output of said bridge, a second input and an output, a first circuit including a voltage polarity reversal means and an integrator connected in series between the output and second input of said amplifier, said integrator having an input connected to the output of said amplifier, and output connected to the second input of said amplifier and a control connection, and a second circuit between the first circuit on the input side of said integrator and said control connection, said second circuit including switch means operable when there is no workpiece in the mill to provide a signal to said control connection to cause said integrator to be in its operate mode and operable when there is a workpiece in said mill to provide a signal to said control connection to cause said integrator to be in its hold mode whereby the output of said amplifier is proportional only to the roll separatingm force when a workpiece is in the mill.
  • Apparatus according to claim 8 including a potentiometer in said first circuit connected to the input of said integrator to control the speed of drift compedsation.
  • Apparatus according to claim 9 including a bypass circuit around said potentiometer having a normally open switch therein, a normally closed switch in said second circuit, and a power source connectable to said control connection when said normally closed switch is opened.
  • said switch means includes a comparator, and means for supplying a desired voltage to said comparator.
  • Apparatus according to claim 11 including a potentiometer in said first circuit connected to the input of said integrator to control the speed of drift compensation.
  • Apparatus according to claim 12 including a bypass circuit around said potentiometer having a normally open switch therein, a normally closed switch in said second circuit, and a power source connectable to said control connection when said normally closed switch is opened.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Soil Working Implements (AREA)
  • Controlling Rewinding, Feeding, Winding, Or Abnormalities Of Webs (AREA)
  • Registering, Tensioning, Guiding Webs, And Rollers Therefor (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)
  • Constituent Portions Of Griding Lathes, Driving, Sensing And Control (AREA)
  • Feedback Control In General (AREA)
  • Measurement Of Force In General (AREA)
  • Indication And Recording Devices For Special Purposes And Tariff Metering Devices (AREA)
US00173436A 1971-08-20 1971-08-20 Drift corrector for transducers Expired - Lifetime US3714806A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US17343671A 1971-08-20 1971-08-20

Publications (1)

Publication Number Publication Date
US3714806A true US3714806A (en) 1973-02-06

Family

ID=22632011

Family Applications (1)

Application Number Title Priority Date Filing Date
US00173436A Expired - Lifetime US3714806A (en) 1971-08-20 1971-08-20 Drift corrector for transducers

Country Status (13)

Country Link
US (1) US3714806A (pt)
JP (1) JPS4830475A (pt)
BE (1) BE787685A (pt)
BR (1) BR7205608D0 (pt)
CA (1) CA951136A (pt)
DE (1) DE2240766A1 (pt)
ES (1) ES405980A1 (pt)
FR (1) FR2151321A5 (pt)
GB (1) GB1407455A (pt)
IT (1) IT969542B (pt)
NL (1) NL7211354A (pt)
NO (1) NO137664C (pt)
SE (1) SE386088B (pt)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3781869A (en) * 1972-03-20 1973-12-25 Inservco Inc Transducer amplifier with automatic balance
US3791204A (en) * 1972-08-28 1974-02-12 Bethlehem Steel Corp Rolling mill force measuring apparatus
US3847017A (en) * 1972-03-20 1974-11-12 Welwyn Electric Ltd Strain measuring system
US3924458A (en) * 1974-04-01 1975-12-09 Us Navy Pressure sensitive control device
US3960010A (en) * 1973-10-23 1976-06-01 Ab Bofors Analog-digital converter for a resistance bridge
US4010644A (en) * 1974-03-05 1977-03-08 Ludwig Krohne K.G. Method for compensation of the electrochemical perturbing direct current potential in inductive flow measurement with a periodically switched uniform field
DE2730028A1 (de) * 1976-10-08 1978-04-13 Bethlehem Steel Corp Messvorrichtung fuer walzkraefte
EP0008520A1 (en) * 1978-08-22 1980-03-05 Frank R. Dybel Improvements in and relating to load monitoring systems and methods
FR2509923A1 (fr) * 1981-07-17 1983-01-21 Hilti Ag Circuit d'evaluation de signal electrique de couple sur une perceuse
US4461182A (en) * 1982-07-23 1984-07-24 Niagara Machine & Tool Works Load measuring apparatus
US4491000A (en) * 1983-06-30 1985-01-01 General Electric Company Method and apparatus for improved sensing of roll separation force in a rolling mill
US4790164A (en) * 1985-08-19 1988-12-13 Herbert Rothe Roller entry guide
US5187986A (en) * 1990-02-06 1993-02-23 Honda Giken Kogyo Kabushiki Kaisha Semiconductor sensor
US5901591A (en) * 1996-04-29 1999-05-11 Tippins Incorporated Pinch roll shapemetering apparatus

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57173702A (en) * 1981-04-18 1982-10-26 Kyowa Dengiyou:Kk Strain measuring device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2342374A (en) * 1941-03-19 1944-02-22 Sperry Prod Inc Strain gauge for rolling mills and the like
US3541320A (en) * 1968-08-07 1970-11-17 Gen Electric Drift compensation for integrating amplifiers
US3667041A (en) * 1969-12-04 1972-05-30 Blh Electronics Automatic zero circuitry for indicating devices

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2342374A (en) * 1941-03-19 1944-02-22 Sperry Prod Inc Strain gauge for rolling mills and the like
US3541320A (en) * 1968-08-07 1970-11-17 Gen Electric Drift compensation for integrating amplifiers
US3667041A (en) * 1969-12-04 1972-05-30 Blh Electronics Automatic zero circuitry for indicating devices

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3781869A (en) * 1972-03-20 1973-12-25 Inservco Inc Transducer amplifier with automatic balance
US3847017A (en) * 1972-03-20 1974-11-12 Welwyn Electric Ltd Strain measuring system
US3791204A (en) * 1972-08-28 1974-02-12 Bethlehem Steel Corp Rolling mill force measuring apparatus
US3960010A (en) * 1973-10-23 1976-06-01 Ab Bofors Analog-digital converter for a resistance bridge
US4010644A (en) * 1974-03-05 1977-03-08 Ludwig Krohne K.G. Method for compensation of the electrochemical perturbing direct current potential in inductive flow measurement with a periodically switched uniform field
US3924458A (en) * 1974-04-01 1975-12-09 Us Navy Pressure sensitive control device
DE2730028A1 (de) * 1976-10-08 1978-04-13 Bethlehem Steel Corp Messvorrichtung fuer walzkraefte
EP0008520A1 (en) * 1978-08-22 1980-03-05 Frank R. Dybel Improvements in and relating to load monitoring systems and methods
FR2509923A1 (fr) * 1981-07-17 1983-01-21 Hilti Ag Circuit d'evaluation de signal electrique de couple sur une perceuse
US4461182A (en) * 1982-07-23 1984-07-24 Niagara Machine & Tool Works Load measuring apparatus
US4491000A (en) * 1983-06-30 1985-01-01 General Electric Company Method and apparatus for improved sensing of roll separation force in a rolling mill
US4790164A (en) * 1985-08-19 1988-12-13 Herbert Rothe Roller entry guide
US5187986A (en) * 1990-02-06 1993-02-23 Honda Giken Kogyo Kabushiki Kaisha Semiconductor sensor
US5901591A (en) * 1996-04-29 1999-05-11 Tippins Incorporated Pinch roll shapemetering apparatus

Also Published As

Publication number Publication date
JPS4830475A (pt) 1973-04-21
FR2151321A5 (pt) 1973-04-13
GB1407455A (en) 1975-09-24
CA951136A (en) 1974-07-16
SE386088B (sv) 1976-08-02
NO137664B (no) 1977-12-19
NL7211354A (pt) 1973-02-22
NO137664C (no) 1978-04-05
BR7205608D0 (pt) 1973-08-23
IT969542B (it) 1974-04-10
BE787685A (fr) 1973-02-19
ES405980A1 (es) 1975-09-16
DE2240766A1 (de) 1973-02-22

Similar Documents

Publication Publication Date Title
GB982232A (en) Improvements in or relating to automatic strip gauge control for a rolling mill
GB959800A (en) Method and apparatus for correcting the gauge of strip during rolling
GB892058A (en) Improvements in or relating to rolling mills
US3938360A (en) Shape control method and system for a rolling mill
US3791204A (en) Rolling mill force measuring apparatus
NO137664B (no) Avdriftskorreksjonsanordning for en deformasjonsm}ler
GB1270246A (en) Improvements in or relating to rolling
US4491000A (en) Method and apparatus for improved sensing of roll separation force in a rolling mill
US3128630A (en) Measurement and control of thickness in the production of sheet and strip material
US4033183A (en) Horizontal- and vertical-roll force measuring system
US2323267A (en) Strain gauge for rolling mills and the like
EP0087083B1 (en) Gauge control method and apparatus for multi-roll rolling mill
CA1122307A (en) Automatic gauge control in tandem strip mills
GB898613A (en) Automatic control system for continuous strip mill
US3331229A (en) Process and apparatus for eliminating the excentricity effect of rollers in hot and cold rolling mills for metal sheets
US3266279A (en) Automatic gauge control system for rolling mills
GB1270788A (en) Improvements in or relating to cold rolling stands
US3875775A (en) Device for automatic adjustment of strip thickness in rolling
GB957714A (en) Improvements in or relating to temper mills
US3383591A (en) Method and apparatus for indicating wear on rolls by combining signals proportional to rolling force and speed
JPH0545325B2 (pt)
US3926024A (en) Method and device for regulating the thickness of rolled products
CA1229395A (en) Method and apparatus for improved sensing of roll separation force in a rolling mill
US2506106A (en) Relative speed indicating system
SU1193452A2 (ru) Тензометрическое устройство с автоматической установкой нул

Legal Events

Date Code Title Description
AS Assignment

Owner name: USX CORPORATION, A CORP. OF DE, STATELESS

Free format text: MERGER;ASSIGNOR:UNITED STATES STEEL CORPORATION (MERGED INTO);REEL/FRAME:005060/0960

Effective date: 19880112