基于电感传感器的钢珠直径分选器设计Designofballdiameterseparatorbasedoninductancesensor

1、基于电感传感器的钢珠直径分选器设计（design of ball diameter separator based on inductance sensor）the first19 the first.2)electronic design engineeringin 2011,in januaryvol. 19 no. 2electronicthe designengineeringjan.2011design of ball diameter separator based on inductance sensorchen yuzhong1, 2,river university, nan

2、jing, jiangsu province210098;2. nanjing branch of jiangsu joint vocational and technical college nanjing210019).abstract: based on the application of inductance sensor in the diameter separation circuit of steel ball, the design idea of the application circuit of inductive sensor is presented, which

3、 is the circuit function analysis,block diagram design and measurement circuit simulation, detect the micro-displacement signal of steel bead diameter and replace it with the voltage signal for transmission, processing and displaythe signal processing and display circuit measure data to realize the

4、classification selection and counting function. the experimental results show that the system has simple structure, high precision and good safety performance.low cost and convenient debugging can meet the measurement requirements in actual engineering.keywords: inductive sensor; diameter; classifie

5、r; phase sensitive detectormiddle image classification no. :tp212.9 document identification code:a post no. : 1674-6236 (2011) 02-0062-04the designofsteelballthe diameterthe separator-basedoninductancethe typetransducerchen,yu - zhong1, 2(1.hohaiuniversity, a working210098china;2.jiangsuthe uniontec

6、hnicalinstitute, a working210019, china)the abstract:thethe articletooktheapplicationofinductancethe typetransducerthe insteelballthe diametersortingcircuitthe asthe anexamplethe tothe presentthethe designconceptionthe forapplicationcircuitofinductancethe typethe transducer,which?containedthe functi

7、onalanalysisofcircuit,the frameworkthe designthe andmeasuringcircuitsimulation.wedetectedthemicro - belowsignals.ofsteelballdiametersthe andturnedthemintovoltagesignals,which?wereeasythe tothe transmit,the processthe andthe display.wetheninforms thesignalprocessingthe anddisplayedcircuitsthe tothe m

8、easurethethe datathe andachievedthesortingthe andcountingfunctions provides. throughthethe experiment, itshowsthatthethe systemissimple,highprecision,goodsafetythe performance,low,cost,was debuggingeasily,the andmeetsthemeasurementrequirementsthe intheactualthe project.the keywords:inductancethe typ

9、etransducer;the diameter;the separator;phasesensitivethe detectorthe sensor is a tool for gathering and retrieving information"electric facial features"1. sensor dc power supply, sensor, dc motor and signal processing circuit module.1.the application of the device and its technology is ver

10、y extensive. it has permeated the basic structure of household, agriculture, industry and medicine 1.1learning, military, environmental protection, transportation and other industries, the automation degree of the system and the inductance sensor of the sensor are composed of coil and ferrite core,

11、as shown in the figure1quality control plays an important role. in modern industrial production, it is often necessary to measure and judge. formula (1) is the mathematical model of inductance sensor1.whether the diameter of the steel ball workpiece is within the allowable range, it needs to be in l

12、ine with a standard diameter l =n2 mu s(1)it can be concluded that the manual detection is not 2 delta in speed and precisionin reality, automatic detection must be realized with the help of advanced technology. effectively get testedthe signal is the key, the best component for obtaining the signal

13、 is the sensor, this articleselect inductance sensorthe typethe signal is picked up as a signalthe source will convert the small change in the geometry of the measuring parts into the inductance of the coilthe measurement is reliable, high sensitivity, long life, linear and good resolutionhigh accur

14、acy, stable performance and good repeatability.inductive sensor1in measuring technology, inductive sensor is widely used for acceleration, displacement and vibrationthe measurement of non-electric quantity such as amplitude, rotating speed and non-destructive testing2. in its control system, the ste

15、el bead type (1)l is the inductance, n is the number of turns of the coil, mu is the air gap permeability, s isthe diameter classifier (abbreviator) is1 micro-displacement detection device, realizing the air gap section area, delta is the air gap thickness.the detection and counting of steel bead si

16、ze are typical applications of inductive sensors. it is known that coil inductancel and air gap thicknessdelta is inversely proportional to the air gap sectionthe measurement and control system adopts the bosch rexroth sensor experiment device, which is the test bed and product of the sensors is pro

17、portional. suppose the air gap at the starting position isdelta zero, the corresponding initial inductancedate of collection: 2010-09-13 manuscript number: 201009041author: chen yu-zhong (1981 -), male, jiangsu yancheng, postgraduate, lecturer. research direction: sensor and detection technology, el

18、ectronic technology.- 62.figure1 excitation elementfig.1incentiveelementdesign of steel bead diameter separator based on inductance sensorl0, ands is constant, whendelta has a subtle change delta, caused by the self inductancechange the amountdl is (ignoring the higher order term) 2 :1 l delta t. de

19、lta t.= =! 1 - delta t."l0the delta the delta delta 0 0 +the delta 0sensitivity: k delta= ldelta t.=l the delta 00=n22 mu delta 201.2 working principleinductance sensor is based on electromagnetic field theory and is used for measurementthe variation of magnetoresistance of magnetic flux is the

20、 change of the inductance or mutual coefficient of the sensor coilthe inductance of the coil is changed to achieve the non-electric measurement1-3.when alternating current flows through the coil, the coil produces alternating magnetic fields that pass throughthe core is directed to the core of the i

21、ron core, which is the excitation end of the sensor. when there are metal objects orthe magnetic field deforms when the magnetic object is close to the excitation end of the sensor. use computersimulation of magnetic field status graph, as shown2. from figureyou can see the conductionmaterials (such

22、 as steel plates) close to the excitation end of the magnetic field effect, the changing magnetic field leads to transmissionthe impedance of the inductor coil changes.figure2 magnetic state diagramfig.2the statechartofmagneticthe sensor coil forms the primary windings of the transformer, and the me

23、tal plates constitute a short circuit secondarywinding, pictured3. due to the coupling of inductance, it is produced in the secondary loopinduced currenti2it is also reactive to the primary loop, resulting in mutual inductancem12. the mostthe impedance of the coil itself varies2. through the ideal t

24、ransformer circuitin comparison, the following conclusions can be drawn:primary loop:u army1 = (r1 + j omega l1)i duo1 + j omega m12i duotwo (2)secondary loop:u army2 = (r2 + j omega l2) i duo1 + j omega m12i duo1 (3)primary loop impedance:12z =u army1 = r1 + j omega l1 + (r2 - j omega l2)omega 2 m2

25、(4)12real component:i1re (z) = r1 + r2r22 +omega r (222m + omegal2(2.)l22) 2 (5)imaginary part:im (z) = omega l1 + omega l2r22 +omega (2 m omega l1222) 2 (6)figureequivalent circuit diagram of transformerfig.3circuitofthe transformerequivalentto sum up, the impedance of the coil when a conductive ma

26、terial is close to the sensorz realthe value increases, and its value is equal to the coil resistancer1addr2, l2, m12andomega resistanceresistance. experience shows that impedancethe virtual value of z only indicates the sensor coil and the metal platethere are small spacing between the measurements

27、. inductive sensors can only use impedancezthe change in real value of the actual value of the conducting material is measured.2 industrial application2.1 functional analysisnominal diameter of steel beads (9.000)mm) control, allow tolerance rangeplus or minus 3mu m, qualified products within this r

28、ange, should be retained and exceededthe inferior quality shall be removed and the quantity of qualified products and defective products shall be automatically counted. will pick upsignal (error signal) and the standard signal (9mm value) contrast, if inplus or minus 3fei mu min the enclosure, the a

29、utomatic counting of qualified products (c1 = cn1 + 1), if beyond this range, thenthe automatic counting of defective products (c2 = cn2 + 1), when the number of qualified products and the number of products is equal to the productwhen the total number of products, automatic exit detection system 2-

30、3. circuit design flow chart4.figure4 circuit design processfig.4the designofthe processcircuit2.2 system block diagram designaccording to the working principle of inductance sensor, it is designed according to the electric pneumatic control circuitdetection circuit. the circuit is divided into two

31、parts: mechanical control and electrical measurement. machinethe control part mainly completes the selection of inductive sensor, the push and positioning of the steel ball,the control function of the cylinder and material box. the electrical measurement section mainly completes the signal pickup,si

32、gnal processing and display function. digital oscilloscope can be used in the detection processdynamic observation and measurement of output signals 4-5. steel bead diameter separator measurement and control systemthe schematic diagram of the circuit schematic diagram5.2.3 working principle2.3.1 mec

33、hanical control circuitwhen the cylinder comes into the aira.0.8mpa high pressure intake, the cylinder front room residuesave gas byb remove, the piston moves from left to right, pushing the steel bead of the feeding portbelow the inductive sensor for picking up signals2, 6. during the test, the pis

34、ton willcontrolled by solenoid valve drive circuit, piston air outletb change to air inletinto the0.8mpa's high pressure air intakea changed the air port to remove the gas from the pistonthe piston automatically recovers its initial state and waits for the next steel ball. in order to finedo cou

35、nt the dimensions of each ball9mm is the standard diameter of steel ball, press1the difference of mu m is divided by -3, -2, -1, 0, 1, 2, 3mu m and defective goodseight etc.level, corresponding8 collecting boxes, each of the top of each box are controllable activitiesboard,eight of the corresponding

36、 electromagnet drive circuit control, and finally by countingthe device feedback the statistical results of each size ball to the computer and display it.2.3.2 electrical measurement circuit1) signal pickup modulein this case, consider1the detection accuracy of mu m orders of magnitude is higher, de

37、tection transmission- 63.electronic design engineering, 20112)figure5 circuit schematic diagramfig.5circuitprinciplethe diagramthe choice of sensor is very important to the final result, and choose the appropriate transmissionsensors can minimize interference. so usingad698 7 high precision linearit

38、ydifferential inductance sensor (lvdt: linearvariabledifferentialtransformer is the signal pickup circuit, which uses the mechanical displacement of the magnetic core as inputthe flow voltage signal is output, and the voltage is proportional to the magnetic core position. primary sensorthe circle is

39、 stimulated by external reference sine wave signal source, two secondary coils in reverse tandem, magneticthe movement of the core can change the coupling flux between the primary coils, resulting in two amplifiersthe value of different ac voltage signals to meet the signal requirements of subsequen

40、t circuits.2) signal processing modulethe circuit of phase sensitive detection circuit, standard signal setting circuit, voltage comparison amplifier circuitand the electromagnetic drive circuit is made up of 8. the identification of phase sensitive detection circuit is completedsignal phase and fre

41、quency selection function, as shown6.figure6 phase sensitive detection circuitfig.6phasesensitivethe detectorphase sensitive detection circuitcircuit composition: 4 performance consistent rectifier diodesvd1 vd4series into aa closed bridge, four nodesa, b, c and d are respectively connected to the t

42、ransformert1, t2thesecondary coil, input signaluyiand the reference voltage of the detectoruy0after respectivelyt1, t2two opposite corners of the bridge, the resistance in the bridger1 and r4for current limiting resistance,resistance tor, to protect the bridge arm diode.u0 > >uyi = u1 + u2, an

43、dwithuyisame frequency to ensure accurate controlthe lead state of four diodes.- 64.2.-working principle: when the armature is moving above the zero point (midpoint), it is displacementx (t)> 0, uyiwithuyosame frequency.whenuyiwithuy0it's half a week, t1the secondary coil output voltageu1fort

44、he top is negative, and according to the identity of the same name, u2it's also going to be negative; t2secondary coilthe output voltageu01negative for the left right, and according to the namesake, u02it's also left rightnegative. according to the circuit analysis principle 3, the secondary

45、 output of transformer at all levels is:u01= u02=2 un02 (7)u1 = u2 =2 unyi1 (n1, n2)respectivelyt1, t2ratio of turns) (8)circuit current is:il =u2rl (9)r2the output voltage is:ux1 = ilrl =rluyi(10)n1 (r + 2 rl)whenuyiwithuy0it's the same thing with negative half a week.when the armature is movin

46、g below zero (midpoint), it is displacementx (t) < 0, uyiwithuyosame frequency inverting phase.at this point, whateveruyiwithuy0is the positive half week or the negative half week, the output voltage is:rluyiux1= ilrl = -n1 (r + 2rl) (11)(among them, "-" reflects the relationship of the

47、 phase, the difference180 °)in conclusion, the change of output voltage of phase sensitive detection circuit reflects the displacementthe law of changeux1the magnitude reflects the displacementthe magnitude of x (t) varies in sizesex reflects displacementx (t) direction (positive displacement o

48、utput positive voltage, negative displacement lossthe waveform diagram of the voltage between the voltages is shown7.as shown in figure7, ux1each cycle can be broken down4 stages:the firstphase 1: positive half - week rise, ux1 > 0, and increasing trend, known as the titleiron upward movement;the

49、 firstphase 2: positive half - week drop, ux1 > 0, and decreasing trend, can be known as the titleiron down;the firstphase 3: negative semi - half - week drop, ux1 < 0, and increasing trend, can be seen as the titledesign of steel bead diameter separator based on inductance sensoriron down;the

50、 firstphase 4: negative half - week rise, ux1 < 0, and decreasing trend, can be known as the titleiron moves upward.figure7 phase sensitive detection circuit waveformfig.7waveformofphasesensitivethe detectorother circuitfor analysis purposesr1, rp1, rp23 resistance composition99 mm,plus or minus

51、3 mmmu m,any standard rating is set to standard signal file, which can be selected by selecting different criteriato meet the standard quantity and the phase sensitive detection signal (error signal)9.when the signal is identical (within the margin of error), the voltage amplifier is used to drive t

52、he electromagneticthe controller1 7, open the corresponding steel bead collecting box, and count the number. when the signal is notin the same case (out of error range), the amplifier is used to drive the electromagnetic controlcontroller8. open the secondary steel bead collecting box and count the number, as shown in the figure8.figure8 other circuitsfig.8theot