CN101963570A - Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit - Google Patents
Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit Download PDFInfo
- Publication number
- CN101963570A CN101963570A CN 201010175554 CN201010175554A CN101963570A CN 101963570 A CN101963570 A CN 101963570A CN 201010175554 CN201010175554 CN 201010175554 CN 201010175554 A CN201010175554 A CN 201010175554A CN 101963570 A CN101963570 A CN 101963570A
- Authority
- CN
- China
- Prior art keywords
- coil
- signal
- circuit
- magnetic
- lubricating oil
- 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.)
- Granted
Links
Images
Abstract
The invention discloses a method for rapidly detecting ferromagnetic grain content in lubricating oil and a detection device thereof as well as a signal processing circuit. A transformer type electromagnetic sensor is adopted, and variation of related parameters of the electromagnetic sensor which is caused by variation of field distribution due to ferromagnetic grain in lubricating oil is detected, so as to detect ferromagnetic substance content in lubricating oil. Influence of nonferromagnetic pollutant can be naturally eliminated, higher linearity can be realized, meanwhile cost is low, and real time property is good.
Description
Technical field
The present invention discloses a kind of detection method and pick-up unit and signal processing circuit of ferro element, the device of ferromagnetic abrasive particle and detection method and signal processing circuit in particularly a kind of fast detecting lubricating oil.
Background technology
Machine power parts of the prior art mainly are that make on the basis with the ferrous material, and in use, this part part often needs to have higher mechanical properties than general parts, at present, this performance is mainly handled by material surface and is obtained, a phenomenon so just occurring, promptly is that often this parts surface is dense, hardness ratio is higher, anti-wear performance is good, and the proportion of the oxide of carbon content, iron is bigger; More then just opposite inward, particle is relatively large, material is softer relatively, and anti-wear performance is poor, carbon and ferriferous oxide content are lower, and iron simple substance proportion is and increases gradually, and particle is also bigger, and this provides important information to mechanical fault diagnosis.In mechanical drive, use lubricating oil through regular meeting; lubricating oil cans be compared to the blood of plant equipment; and all friction pairs generation wear particles all can flow in the lubricating oil; thereby make lubricating oil become the carrier of mechanical wear information; ferromagnetism abrasive particle by monitoring lubricating oil; can learn wear condition, the operation conditions of precognition machine and the discovery potential faults of machine according to what, size analysis of ferromagnetic particle.
At present a lot of to the detection means of lubricant iron abrasive particle, such as analyzing iron spectrum, spectral analysis, particle collector or the like.(1), the analyzing iron spectrum technology is to utilize the magnetic field of high gradient, abrasive dust particle in the oil is separated with fluid and impurity, and make it according to certain rules, be deposited on the glass sheet that places the top, magnetic field, form the spectrum sheet, utilize optical microscope system that the abrasive dust of spectrum on the sheet carried out the observation of size, shape, color and luster, superficial makings etc. again, again wear type is differentiated and classified.Its feature is the size that can observe abrasive particle, pattern, color etc., but needs sample pretreatment, and sense cycle is long, the process flow complexity, and conditional request is higher, and operating personnel need possess certain quality and experience, is unfavorable for that the scene tests.(2), spectral analysis is to utilize each element that the fact of its distinctive atomic structure is all arranged.When atomic absorption during to additional energy, its extranulear electron will get on from the track that low-lying level transits to high level, at this moment atom plays pendulum, atom returns the electromagnetic wave energy that steady state (SS) will discharge certain frequency by non-steady state, and every kind of element sends the light or the color of peculiar wavelength.The light that gives off through chromatic dispersion, is obtained the line spectrum of arranging by wavelength, has or not to occur judging whether certain material exists according to characteristic spectral line, according to the power of characteristic spectral line judge this content of material how much.Its feature be can be in 30 seconds Accurate Analysis go out (PPM level) content of nearly 20 kinds (can reach 32 kinds at most) elements in the fluid, can analyze various wear metal element of Fe, Cu, Al, Pb in lubricating oil and the hydraulic oil, the concentration of additive element S, P, Ca, Ba and outside contamination elements Si.But, its volume heaviness, huge, testing cost costliness.(3), the ultimate principle of particle collector is to utilize to flow through kapillary with sample, in a side capillaceous LASER Light Source is housed, opposite side dress optical amplification system arranged, and imageing sensor, when oil sample has abrasive Flow out-of-date, abrasive particle is imaging on sensor, just size and the number that can know the size of abrasive particle according to the size and the pulse number of imaging, its weak point is the material that can not detect particle diameter, often contain different particle type in the lubricating oil, such as carbon granules, greasy filth and various oxides etc., and bulky, particle collector can only be discerned size and number, and the iron abrasive particle what can not react.Above-mentioned these methods mostly just are suitable for lab analysis and use.
Summary of the invention
At the shortcoming of iron abrasive particle detection method in the above-mentioned lubricating oil of mentioning of the prior art, the invention provides a kind of simply, feasible, and analysis speed detection method and device fast, with low cost solved above-mentioned technical matters.
The technical scheme that the present invention solves its technical matters employing is: the device of ferromagnetic abrasive particle content and this method of detection method are for to be respectively arranged with a magnetic test coil and a balancing coil an equidistant position, drive coil two ends with alternating magnetic field in a kind of fast detecting lubricating oil, with close one of them magnetic induction loop of specimen, detect two magnetic induction loop induced signals, and induced signal carried out integration and amplification, calculate by the difference of two signals and contain what of ferromagnetic abrasive particle in the sample.
A kind of pick-up unit of realizing said method, comprise a drive coil with alternating magnetic field, magnetic test coil and balancing coil, detection rotating disk and detection signal treatment circuit, two magnetic induction loops are separately positioned on equidistant place, drive coil two ends, one of them magnetic induction loop is an inductive coil, another magnetic induction loop is a balancing coil, detect rotating disk near the inductive coil setting, inductive coil and balancing coil are exported induced signal respectively and are given the detection signal treatment circuit.
A kind of feeble signal treatment circuit that is used for said method, this circuit comprises the detection electric bridge, sampling holder, comparer, direct current amplifier, analog to digital converter and single-chip microcomputer, two magnetic induction loops are exported induced signal respectively and are detected to detecting electric bridge, detect the electric bridge output detection signal and carry out the signal maintenance to sampling holder, the holding signal that sampling holder is exported two magnetic induction loop induced signals respectively compares to comparer, comparer is exported to direct current amplifier with the signal comparative result and is carried out the signal amplification, and the signal after the amplification converts digital signal to through analog to digital converter and handles to single-chip microcomputer.
The technical scheme that the present invention solves its technical matters employing further comprises:
The conversion frequency of described alternating magnetic field is 1KHz～5KHz.
Described magnetic core adopts on the cylindricality iron core and forms around last drive coil, to the pumping signal of drive coil feeding conversion, makes it produce alternating magnetic field.
Described pumping signal is a sinusoidal signal.
Described drive coil, balancing coil and magnetic test coil are vertically arranged, and inductive coil and balancing coil are separately positioned on drive coil equidistant place, two ends up and down, detect rotating disk and are horizontally disposed with; Described pick-up unit also includes the base and cover plate, and cover plate is arranged on the pedestal, and magnetic core fixedly mounts on the cover board, and inductive coil is arranged on the cover plate top, and balancing coil is arranged on the cover plate below, detects rotating disk and is installed in the inductive coil top.
Described pedestal internal fixation is equipped with motor, and motor-driven detects dial rotation, and the effect of motor is auxiliary with sample be delivered to sensor respectively with reference to standard specimen and detect and compare, makes to measure to reduce to disturb and think the site error of placing generation.
Described pedestal is provided with the display device that is used to show testing result, the detection signal treatment circuit.
Be provided with transformer in the described pedestal, give the power supply of motor and detection signal treatment circuit.
Described circuit also comprises an oscillator.
Described detection electric bridge comprises the brachium pontis of two parallel connections, and a brachium pontis comprises resistance R 23, potentiometer VR1 and the resistance R 33 that is connected in series successively; Another brachium pontis comprises resistance R 24, potentiometer VR2 and the resistance R 34 that is connected in series successively; Two coils are connected to the common node place of two brachium pontis, and potentiometer VR2 exports at two ends the induced signal of two coils respectively.
Described sampling holder adopts four sampling holders to the maintenance of sampling of the positive negative peak of two coil detection signals respectively, and four sampling holders are controlled by trigger circuit.
Described trigger circuit comprise reference circuit, two comparator circuits and two stabilivolts, the reverse input end of reference circuit output reference signal to two comparator circuit, the induced signal that detects electric bridge output directly is connected the in-phase input end of first comparator circuit, the induced signal that detects electric bridge output is by being connected the in-phase input end of second comparator circuit after reverse, be connected with a stabilivolt on the output terminal of two comparator circuits respectively, first comparator circuit output triggers control signal and gives two sampling holders that keep the detection signal positive peak respectively, and second comparator circuit output triggers control signal and gives two sampling holders that keep the detection signal negative peak respectively.
Described sampling holder is divided into four the tunnel, every road comprises two operational amplifiers, the coil detection signal is imported the in-phase input end of first amplifier, the reverse input end of first amplifier is connected with the in-phase input end of second amplifier by a resistance, be in series with one first diode between the in-phase input end of the output terminal of first amplifier and second amplifier, be in series with one second diode between the reverse input end of first amplifier and the output terminal of first amplifier, the reverse input end of output terminal feedback signal to the second amplifier of second amplifier; When sampling holder kept the detection signal positive peak, first diode cathode was connected with the output terminal of first amplifier respectively with second diode cathode; When sampling holder kept the detection signal negative peak, first diode cathode was connected with the output terminal of first amplifier respectively with second diode cathode.
The invention has the beneficial effects as follows: the present invention adopts inductive electromagnetic method to be used for detection by quantitative lubricating oil abrasive dust superior performance.It adopts the electromagnetic sensor of transformer shape, and the space magnetic field change that causes by the iron abrasive dust that detects deposition causes the change of electromagnetic sensor parameter to detect.The influence that non-ferromagnetic pollutant brings can be got rid of naturally, higher linearity can be reached.And the also creationary inductive coil of having realized two ends under the non-detection status of the present invention guarantees in full accordly, averages out.The present invention realizes the signal Processing of efficient stable with succinct treatment scheme, the low element that requires, cheap cost.The present invention carries out phase-modulation and amplitude-modulation with a kind of method that does not increase the useful signal white noise, as the signal processing flow prime; Is that direct current signal is protected with a kind of method of extracting interchange useful signal eigenwert with useful parameter change, as the signal processing flow stage casing; Greatly eliminate the white noise from chip, the influence of external electromagnetic field with a kind of direct current useful signal and the differentiation amplifier that exchanges noise as the back level, level behind the signal processing flow.The present invention realizes passive phase-modulation and amplitude-modulation with impedance match method, can not produce the white noise influence and exchange useful signal.Can produce white noise owing to form the used chip of active circuit itself, introduce white noise after level amplification later just can produce the new interference that exchanges useful signal that is superimposed upon by the prime chip, and white noise comprises the noise signal of various frequencies, therefore is difficult to remove fully its influence to useful signal again.The present invention adjusts the action that phase place is adjusted amplitude at the elementary active circuit that do not use that two-way exchanges useful signal, in order to avoid introduce white noise, adopts a kind of more efficient signal treatment scheme to reach better effect.The two-way initialize signal was identical on phase place and amplitude after phase-modulation and amplitude-modulation was finished, and will exchange the useful parameter of useful signal this moment again by the peak value sampling circuit: crest or trough are protected with the form of direct current amplitude signal; Through behind the peak value sampling, useful signal changes the direct current form into, is different from white noise that chip produces fully and from the interference of space magnetic field, draws the difference of detection signal and reference signal this moment by difference channel; Pass through again direct current amplifier to difference after the amplification of signal, just can reach the good signal treatment effect to the inhibition of AC signal; Filter action makes its output more stable to last direct current useful signal through steady, and signal condition is so far finished.The present invention adopts a kind of circuit that is used for Detection of Weak Signals, make its interference of existing of under better simply implementation, forgoing as much as possible (as white noise, temperature float, phase differential of original state, difference in magnitude, electromagnetic field effects or the like), faint useful signal accurately detected and amplify.The present invention sends feeble signal into the safety zone as quickly as possible, adopts useful signal and undesired signal differentiation, and undesired signal after the differentiation and useful signal one press down one to be raised, and finishes signal screening.Thereby obtain optimization effect to signal.
The present invention will be further described below in conjunction with the drawings and specific embodiments.
Description of drawings
Fig. 1 is a physical construction synoptic diagram of the present invention.
Fig. 2 is a circuit block diagram of the present invention.
Fig. 3 is oscillator section circuit theory diagrams of the present invention.
Fig. 4 detects electric bridge partial circuit schematic diagram for the present invention.
Fig. 5 is sampling hold circuit embodiment one circuit theory diagrams of the present invention.
Fig. 6 is trigger circuit circuit theory diagrams of the present invention.
Fig. 7 is sampling hold circuit embodiment two circuit theory diagrams of the present invention.
Fig. 8 is comparer of the present invention and direct current amplifier partial circuit schematic diagram.
Among the figure, 1-pedestal, 2-drive coil, 3-inductive coil, 4-balancing coil, 5-cover plate, 6-annulus, 7-rotating disk, 8-motor, 9-display, 10-transformer.
Embodiment
Present embodiment is the preferred embodiment for the present invention, and other all its principles are identical with present embodiment or approximate with basic structure, all within protection domain of the present invention.
Please referring to accompanying drawing 1, critical piece of the present invention is a drive coil 2, produce an alternating magnetic field by drive coil 2, in the present embodiment, in the middle of the drive coil 2 is a magnetic core, magnetic core adopts winding around formation drive coil 2 on columnar iron core (core material can be selected materials such as the plug steel for use) magnetic core, when feeding exchange current to drive coil, drive coil 2 promptly can produce alternating magnetic field, in the present embodiment, the sinusoidal signal that preferred employing frequency is 1KHz～5KHz makes drive coil 2 produce the alternating magnetic field that frequency is 1KHz～5KHz as exchange current.Equidistant place, drive coil 2 two ends is respectively equipped with a coil, and one of them is as magnetic test coil 3, and another is as balancing coil 4, and magnetic test coil 3 and balancing coil 4 impedances equate.Since near the two ends of drive coil 2, the divergent magnetic field of same distribution can appear, magnetic test coil 3 and balancing coil 4 and drive coil 2 arranged in co-axial alignment, and on the equidistant symmetric position in drive coil 2 two ends, can induce two equal signals in theory.Be provided with a test plane near magnetic test coil 3 one ends, if not with tested oil sample (or in the tested oil sample ferromagnetic abrasive particle content be zero) from the test plane during near magnetic test coil, the output of two coils equates that promptly difference is zero; As the tested oil sample that will contain ferromagnetic abrasive particle during near magnetic test coil, there is ferromagnetic abrasive particle in the oil sample, because ferromagnetic abrasive particle has the effect of little magnetic moment, make magnetic circuit and magnetic field rebulid, reach a new equilibrium system, be that ferromagnetic material causes drive coil 2 to deform near the divergent magnetic field of magnetic test coil 3 one ends, central authorities magnetic field strengthens, the induced signal that so just makes magnetic test coil 3 produce is bigger than the induced signal that balancing coil 4 produces, thereby the output imbalance that causes two coils, thereby make the output signal between magnetic test coil 3 and the balancing coil 4 produce difference, through this difference signal is relatively amplified, shaping and relevant conversions such as integration, just can characterize the ferromagnetism size of the abrasive particle that taps a blast furnace, by identification to this signal magnitude, can calculate the content of the ferromagnetic material in the sample, promptly the difference with two induction coils characterizes out the ferromagnetic abrasive particle content of detected sample.Among the present invention, focus on the detection method of ferromagnetism abrasive particle, the factor that characterizes out the ferromagnetic abrasive particle content of detected sample owing to the difference with two induction coils is more, such as: magnetic test coil 3 and balancing coil 4 are far and near apart from the distance of drive coil, the magnetic field intensity of drive coil, distance of test plan range magnetic test coil 3 or the like, so, be difficult to form a quantitative relation, but, because above-mentioned factor is in case fixing, what of the ferromagnetism abrasive particle content in the lubricating oil then, promptly linear with the size of the difference of magnetic test coil 3 and balancing coil 4 induced signals, so, when a fixed test device was initial, any one technician can determine the difference of magnetic test coil 3 and balancing coil 4 induced signals and the funtcional relationship between the ferromagnetism abrasive particle content by the experiment of limited number of time.
Among the present invention critical piece is installed in the pedestal 1, forms the pick-up unit of an integral body.Pedestal 1 top is provided with cover plate 5, and drive coil 2 is installed on the cover plate 5, and in the present embodiment, for easy to use, drive coil 2 vertically is provided with, and drive coil 2 is fixedly mounted on the cover plate 5 by a notched annulus 6.In the present embodiment, magnetic test coil 3 is arranged on cover plate 5 tops, and balancing coil 4 is arranged on the below, and magnetic test coil 3 and balancing coil 4 are with respect to drive coil 2 equidistant being symmetrical arranged.Cover plate 5 tops are equipped with a rotating disk 7, and rotating disk 7 is the test plane, and pedestal 1 internal fixation is equipped with motor 8, drive rotating disk 7 by motor 8 and rotate.Pedestal 1 internal fixation is equipped with transformer 10, can convert electric main to required voltage by transformer 10, gives motor 8 and the power supply of other circuit parts.Pedestal 1 outside is provided with a display 9, can be used for showing measuring numerical value, and display 9 can adopt charactron or LCDs etc.
Please referring to accompanying drawing 2, the circuit among the present invention mainly comprises oscillator, sensor, detection electric bridge, sampling holder, comparer, direct current amplifier, digital to analog converter and single-chip microcomputer.Please referring to accompanying drawing 3, in the present embodiment, the oscillatory circuit that oscillator is made up of DDS signal generator IC4 and operational amplifier IC6A, operational amplifier IC6B, operational amplifier IC7A, operational amplifier IC7B and power amplifier IC5 and peripheral resistance capacitance, in the present embodiment, the oscillation frequency of the sine wave signal that oscillatory circuit produces is 1KHz, when specifically implementing, also can pass through the regulating circuit parameter, and change its oscillation frequency, its scope is remained between 1KHz～5KHz.Please referring to accompanying drawing 4, in the present embodiment, the solenoid that sensor adopts two inductance values to equate, one of them is as magnetic test coil La, one as balancing coil Lb, detecting electric bridge is the inductance bridge of a non-equilibrium state, detects resistance R 23 and resistance R 33 that electric bridge comprises series connection, is in series with a potentiometer VR1 between resistance R 23 and the resistance R 33, it is first brachium pontis, in the present embodiment, resistance R 23 and resistance R 33 adopt precision resistance, and potentiometer VR1 adopts accurate multiturn potentiometer.Be parallel with second brachium pontis with first brachium pontis, second brachium pontis comprises the resistance R 24 and the resistance R 34 of series connection, be in series with a potentiometer VR2 between resistance R 24 and the resistance R 34, in the present embodiment, resistance R 24 and resistance R 34 adopt precision resistance, potentiometer VR2 adopts accurate multiturn potentiometer, and resistance R 24 is connected in parallel into a loop with resistance R 23 with the branch road that resistance R 33 forms with the branch road that resistance R 34 forms.This circuit loop is by the sliding end separated into two parts of potentiometer VR1 and potentiometer VR2, and two parts are respectively with magnetic test coil La be connected balancing coil Lb connection, and wherein magnetic test coil La output signal is S-org, and balancing coil Lb output signal is B-org.On the common port of potentiometer VR2 and resistance R 34, be connected with reference signal Base, on the common port of potentiometer VR2 and resistance R 24, be connected with sensor output signal Sense.By regulator potentiometer VR1, can guarantee that two resistance brachium pontis resistances equate, thereby the signal amplitude of regulating magnetic test coil La and balancing coil Lb output when work equates; By regulator potentiometer VR2, can guarantee that two resistance brachium pontis resistances equate, thereby it is consistent with the signal phase of balancing coil Lb output when working to regulate magnetic test coil La.In the present embodiment, the amplitude modulation phase modulation is consistent the initial state phase place of two signal circuits by impedance match method, by dividing potential drop the initial state amplitude is equated again, and signal phase is regulated, and can make the signal lead-lag in original phase angle; Amplitude is regulated, and can control the output size of final signal; Phase place, amplitude independent regulation, promptly the phase place of signal is regulated not mutual interference mutually with amplitude.Please referring to accompanying drawing 5, in the present embodiment, sampling hold circuit comprises that sampling keeps chip IC8, sampling to keep chip IC9, sampling to keep chip IC10 and sampling to keep chip IC11 and peripheral resistance capacitance to constitute, four samplings keep the separate settings of chip, the positive negative peak of the induced signal that magnetic test coil La and balancing coil Lb the are produced maintenance of sampling respectively.In the present embodiment, it is the sampling with high precision maintenance chip of LF398 that sampling keeps chip all to adopt model.Sampling hold circuit is controlled trigger angle by trigger circuit.Please referring to accompanying drawing 6, in the present embodiment, trigger circuit are by fiducial chip IC13, operational amplifier IC14A, operational amplifier IC12A, operational amplifier IC12B and potentiometer VR3, potentiometer VR4 and peripheral resistance capacitance constitute, the signal that detects electric bridge output signal and fiducial chip IC13 generation is by operational amplifier IC12A, operational amplifier IC12B relatively after, export to the trigger end that sampling keeps chip respectively, wherein, operational amplifier IC12A exports to sampling and keeps chip IC8 and sampling to keep chip IC9, is used for the maintenance of the positive peak signal of induced signal that magnetic test coil La and balancing coil Lb are produced; Operational amplifier IC12B exports to sampling and keeps chip IC10 and sampling to keep chip IC11, is used for the maintenance of the negative peak signal of induced signal that magnetic test coil La and balancing coil Lb are produced.Can adjust trigger angle by adjusting two potentiometers.Please referring to accompanying drawing 8, in the present embodiment, operational amplifier IC17 and operational amplifier IC18 constitute comparator circuit, induced signal to magnetic test coil La and balancing coil Lb generation compares respectively, in the present embodiment, it is the precision gain differential amplifier of INA105 that operational amplifier IC17 and operational amplifier IC18 adopt model.In the present embodiment, direct current amplifier comprises operational amplifier IC15A, operational amplifier IC15B, operational amplifier IC14B and digital regulation resistance IC16 and peripheral capacitance resistance.After the signal process direct current amplifier amplification by the comparator circuit generation, input to analog to digital converter, in the present embodiment, analog to digital converter comprises that modulus conversion chip IC20 and peripheral resistance capacitance form, and becomes digital signal to input to single-chip microcomputer the conversion of signals of direct current amplifier output and carries out algorithm process.Direct current amplifier comprises that also some play the diode capacitance resistance of automatic compensating action.
In the foregoing description, sampling hold circuit is made up of 4 sampling holders, and by trigger circuit control trigger angle.It is the sampling holder way of realization of logic level control.Under this kind form, sampling holder is a kind of device of controlling its duty with logic level, it has two duties: (1) tracking mode, it receives analog input signal as quickly as possible during this period, and the accurately variation of trace simulation input signal, until receive till the hold instruction; (2) hold mode keeps flashy analog input signal before receiving hold instruction.
In addition, sampling hold circuit can also adopt another kind of form.Please referring to accompanying drawing 7, in the present embodiment, sampling hold circuit comprises positive peak sample circuit and negative peak sample circuit.Wherein, the positive peak sampling hold circuit is made up of operational amplifier IC1 and two operational amplifiers of operational amplifier IC2, the in-phase input end of coil detection signal input operational amplifier IC1, the reverse input end of operational amplifier IC1 is connected with the in-phase input end of operational amplifier IC2 by a resistance R 1, be in series with a diode D1 between the in-phase input end of the output terminal of operational amplifier IC1 and operational amplifier IC2, diode D1 anode connects operational amplifier IC1 output terminal.Be in series with a diode D2 between the reverse input end of operational amplifier IC1 and its output terminal, diode D2 anode connects the reverse input end of operational amplifier IC1.The output terminal feedback signal of operational amplifier IC1 is to the reverse input end of operational amplifier IC2; Negative peak sampling hold circuit and positive peak holding circuit are as good as substantially, and difference is, diode D3, diode D4 direction are opposite with diode D1, diode D2.Under this kind form, sampling hold circuit can obtain the crest or the trough amplitude of AC signal automatically and keep, finish consumable thereby can finish the amplitude that descends is followed the tracks of by electric capacity and resistance, and the characteristic parameter numerical value that the decay in the monocycle is very little can not influence waveform stabilization the time.Under this kind form, sampling hold circuit can obtain the crest or the trough amplitude of AC signal automatically and keep, finish consumable thereby can finish the amplitude that descends is followed the tracks of by electric capacity and resistance, and the characteristic parameter numerical value that the decay in the monocycle is very little can not influence waveform stabilization the time.Under this kind form, sampling hold circuit is the self consumption type peak holding circuit.It possesses two features: (1) its output can need not the amplitude that level control keeps equal size automatically at crest or trough place at signal, when secondary wave crest or trough arrive down, keep numerical value (periodic attenuation is less than 0.4%) (2) if the value after crest or trough change is littler than the previous status as far as possible, this circuit can be by consumable 4% of the former numerical value that descends in 10 cycles, and the crest or the trough value that finally drop to present condition keep this value output again.
Method of the present invention is the using method of said apparatus very, it adopts frequency of oscillator generation to provide pumping signal for the sinusoidal signal of 1KHz～5KHz for magnetic core, make it produce an alternating magnetic field, by detecting electric bridge the signal of inductive coil and balancing coil generation is exported to sampling holder then, convert thereof into peak signal by sampling holder, direct current amplifier compares and exports the peak signal of sampling holder output, and analog to digital converter carries out the direct current signal of direct current amplifier output to export single-chip microcomputer to after the analog to digital conversion.The Micro Controller Unit (MCU) driving display shows measurement result, and the control rotating disk is sent to the inductive coil place with the fluid container.Under normal circumstances, be when not having ferromagnetic material around the inductive coil, comparer is output as zero, when the container that contains ferromagnetic abrasive dust places the inductive coil top, no longer balance is exported at the sensor two ends, this moment is through the peak signal of sampling holder output also balance no longer, and comparer output one and the proportional direct current signal of ferromagnetic abrasive dust content convert that digital signal is handled by single-chip microcomputer to and by the display display result through analog to digital converter after direct current amplifier amplifies.
The present invention adopts inductive electromagnetic method to be used for detection by quantitative lubricating oil abrasive dust superior performance.It adopts the electromagnetic sensor of transformer shape, and the space magnetic field change that causes by detection deposition abrasive dust causes the change of electromagnetic sensor parameter to detect.Packing phenomenon and pollutant effects can be got rid of naturally, higher linearity can be reached.And the also creationary inductive coil of having realized two ends under the non-detection status of the present invention guarantees in full accordly, averages out.The present invention realizes the signal Processing of efficient stable with succinct treatment scheme, the low element that requires, cheap cost.The present invention carries out phase-modulation and amplitude-modulation with a kind of method that does not increase the useful signal white noise, as the signal processing flow prime; Is that direct current signal is protected with a kind of method of extracting interchange useful signal eigenwert with useful parameter change, as the signal processing flow stage casing; Greatly eliminate the white noise from chip, the influence of external electromagnetic field with a kind of direct current useful signal and the differentiation amplifier that exchanges noise as the back level, level behind the signal processing flow.The present invention realizes passive phase-modulation and amplitude-modulation with impedance match method, can not produce the white noise influence and exchange useful signal.Can produce white noise owing to form the used chip of active circuit itself, introduce white noise after level amplification later just can produce the new interference that exchanges useful signal that is superimposed upon by the prime chip, and white noise comprises the noise signal of various frequencies, therefore is difficult to remove fully its influence to useful signal again.The present invention adjusts the action that phase place is adjusted amplitude at the elementary active circuit that do not use that two-way exchanges useful signal, in order to avoid introduce white noise, adopts a kind of more efficient signal treatment scheme to reach better effect.The two-way initialize signal was identical on phase place and amplitude after phase-modulation and amplitude-modulation was finished, and will exchange the useful parameter of useful signal this moment again by the peak value sampling circuit: crest or trough are protected with the form of direct current amplitude signal; Through behind the peak value sampling, useful signal changes the direct current form into, is different from white noise that chip produces fully and from the interference of space magnetic field, draws the difference of detection signal and reference signal this moment by difference channel; Pass through again direct current amplifier to difference after the amplification of signal, just can reach the good signal treatment effect to the inhibition of AC signal; Filter action makes its output more stable to last direct current useful signal through steady, and signal condition is so far finished.The present invention adopts a kind of circuit that is used for Detection of Weak Signals, make its interference of existing of under better simply implementation, forgoing as much as possible (as white noise, temperature float, phase differential of original state, difference in magnitude, electromagnetic field effects or the like), faint useful signal accurately detected and amplify.The present invention sends feeble signal into the safety zone as quickly as possible, adopts useful signal and undesired signal differentiation, and undesired signal after the differentiation and useful signal one press down one to be raised, and finishes signal screening.Thereby obtain optimization effect to signal.
Claims (10)
1. ferromagnetic abrasive particle content detecting method in the fast detecting lubricating oil, it is characterized in that: described method is for to be respectively equipped with a magnetic test coil and a balancing coil an equidistant position, drive coil two ends with alternating magnetic field, with the close magnetic test coil of sample, by the difference of two induction coils of testing circuit detection, utilize the difference of two induction coils to characterize out the ferromagnetic abrasive particle content of detected sample.
2. pick-up unit of realizing ferromagnetic abrasive particle content detecting method in the fast detecting lubricating oil as claimed in claim 1, it is characterized in that: described device comprises a drive coil with alternating magnetic field, magnetic test coil and balancing coil, detection rotating disk and detection signal treatment circuit, magnetic test coil and balancing coil are separately positioned on the equidistant place, magnetic core two ends of drive coil, detect rotating disk near the inductive coil setting, inductive coil and balancing coil are exported induced signal respectively and are given the detection signal treatment circuit.
3. pick-up unit according to claim 2 is characterized in that: described magnetic core vertically is provided with, and inductive coil and balancing coil are separately positioned on magnetic core equidistant place, two ends up and down, detect rotating disk and are horizontally disposed with; When inductive coil is arranged on the magnetic core upper end, detects rotating disk and be arranged on the inductive coil top; When inductive coil is arranged on the magnetic core lower end, detects rotating disk and be arranged on the inductive coil below.
4. according to claim 2 or 3 described pick-up units, it is characterized in that: described pick-up unit also includes the base and cover plate, cover plate is arranged on the pedestal, the drive coil fixed installation on the cover board, magnetic test coil is arranged on the cover plate top, balancing coil is arranged on the cover plate below, detects rotating disk and is installed in the magnetic test coil top.
5. pick-up unit according to claim 4 is characterized in that: described pedestal internal fixation is equipped with motor, and motor-driven detects dial rotation.
6. pick-up unit according to claim 4 is characterized in that: described pedestal is provided with the display device that is used to show testing result, the detection signal treatment circuit.
7. pick-up unit according to claim 4 is characterized in that: be provided with transformer in the described pedestal, give the power supply of motor and detection signal treatment circuit.
8. feeble signal treatment circuit that is used for the ferromagnetic abrasive particle content detecting method of fast detecting lubricating oil as claimed in claim 1 or 2, it is characterized in that: described circuit comprises the detection electric bridge, sampling holder, comparer, direct current amplifier, analog to digital converter and single-chip microcomputer, magnetic test coil and balancing coil are exported induced signal respectively and are detected to detecting electric bridge, detect the electric bridge output detection signal and carry out the signal maintenance to sampling holder, sampling holder is exported two magnetic induction loop induced signals respectively and is carried out differential ratio, and difference signal amplified, the signal after the amplification converts digital signal to through analog to digital converter to carry out related algorithm to single-chip microcomputer and handles and the data of obtaining a result.
9. signal processing circuit according to claim 8 is characterized in that: described circuit also comprises an oscillator.
10. signal processing circuit according to claim 8 is characterized in that: described detection electric bridge comprises the brachium pontis of two parallel connections, and a brachium pontis comprises resistance R 23, potentiometer VR1 and the resistance R 33 that is connected in series successively; Another brachium pontis comprises resistance R 24, potentiometer VR2 and the resistance R 34 that is connected in series successively; Two coils are connected to the common node place of two brachium pontis, and potentiometer VR2 exports at two ends the induced signal of two coils respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101755547A CN101963570B (en) | 2010-05-17 | 2010-05-17 | Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101755547A CN101963570B (en) | 2010-05-17 | 2010-05-17 | Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101963570A true CN101963570A (en) | 2011-02-02 |
| CN101963570B CN101963570B (en) | 2012-08-01 |
Family
ID=43516537
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010101755547A Expired - Fee Related CN101963570B (en) | 2010-05-17 | 2010-05-17 | Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101963570B (en) |
Cited By (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103308431A (en) * | 2013-06-05 | 2013-09-18 | 桂林电子科技大学 | Sensor for monitoring metal abrasive particles in oil liquid on line and application method for sensor |
| CN103344535A (en) * | 2013-06-09 | 2013-10-09 | 桂林电子科技大学 | Oil metal abrasive particles online monitoring system |
| CN103592208A (en) * | 2013-11-13 | 2014-02-19 | 中国人民解放军国防科学技术大学 | Electromagnetic type oil metal particle monitoring sensor resistant to environmental magnetic field interference |
| CN103684176A (en) * | 2013-12-21 | 2014-03-26 | 西安科技大学 | Device and method for determining rotating speed of motor rotor by residual voltage of motor stator winding |
| CN103926276A (en) * | 2014-03-25 | 2014-07-16 | 天津大学 | Online oil liquid abrasive particle monitoring device and measuring method |
| CN104165820A (en) * | 2014-08-19 | 2014-11-26 | 北京华安广通科技发展有限公司 | Sensor for detecting content of ferrum powder in lubricating oil and detecting method |
| WO2015010460A1 (en) * | 2013-07-24 | 2015-01-29 | 中国矿业大学 | System for online monitoring metal abrasive grains in oil liquid and monitoring method therefor |
| CN104539214A (en) * | 2015-01-12 | 2015-04-22 | 深圳市英威腾电气股份有限公司 | Communication circuit used for tracking rotation speed of motor |
| CN105241949A (en) * | 2015-10-16 | 2016-01-13 | 中国航空工业集团公司北京长城航空测控技术研究所 | Detection circuit of grease metal filing online monitor and carrier signal demodulation method |
| CN105547932A (en) * | 2015-12-08 | 2016-05-04 | 中国航空工业集团公司北京长城航空测控技术研究所 | Engine lubricating oil metal particle on-line monitoring signal demodulation method |
| CN105571994A (en) * | 2015-12-11 | 2016-05-11 | 中国航空工业集团公司西安航空计算技术研究所 | Parameter detection method for lubricating oil metal filing of power transmission system |
| CN105865986A (en) * | 2016-05-12 | 2016-08-17 | 绍兴文理学院 | Oil monitoring equipment based on full-band variable-structure working condition adaptive filtering and molding |
| CN105865984A (en) * | 2016-05-12 | 2016-08-17 | 绍兴文理学院 | Oil monitoring method based on full-band variable-structure working condition adaptive filtering and molding |
| CN105891061A (en) * | 2016-05-12 | 2016-08-24 | 绍兴文理学院 | Liquid oil monitoring device adopting full-band and variable-structure filtering, absorbing and shaping |
| CN106483569A (en) * | 2016-12-08 | 2017-03-08 | 华北电力大学（保定） | Balanced differences dynamic formula metal detection sensor and insulation paper detecting apparatus |
| CN107332535A (en) * | 2017-06-26 | 2017-11-07 | 武汉凡谷电子技术股份有限公司 | It is a kind of to be used to adjust the circuit arrangement that microstrip line transmits phase |
| CN107907455A (en) * | 2017-12-05 | 2018-04-13 | 西人马（厦门）科技有限公司 | A kind of magnetic induction grain testing apparatus and concentration detection method |
| CN108051348A (en) * | 2017-12-05 | 2018-05-18 | 西人马（厦门）科技有限公司 | A kind of detecting system and method for fluid non-metallic particle concentration |
| CN109283101A (en) * | 2018-11-19 | 2019-01-29 | 北京理工大学 | A kind of high sensitivity wear particle on-line detecting system and method |
| CN109839334A (en) * | 2019-03-12 | 2019-06-04 | 西安交通大学 | Signal recognition method towards unicoil magnetic inductive abrasive grain detection sensor |
| CN110018094A (en) * | 2019-05-17 | 2019-07-16 | 大连海事大学 | Magnetic core multi-parameter abrasive grain sensing device is set in one kind |
| CN110031373A (en) * | 2019-05-17 | 2019-07-19 | 大连海事大学 | A kind of multi signal synchronous feedback plant of oil liquid detection |
| TWI679412B (en) * | 2019-06-19 | 2019-12-11 | 國立虎尾科技大學 | Detection method of wear debris in lubricating oil |
| CN111433602A (en) * | 2017-12-06 | 2020-07-17 | 昭和电工株式会社 | Method for inspecting lubricating oil composition and method for producing lubricating oil composition |
| CN111721513A (en) * | 2020-06-10 | 2020-09-29 | 山东交通学院 | Analysis method for wear of marine diesel engine |
| CN112014889A (en) * | 2019-05-31 | 2020-12-01 | 株式会社日立大厦系统 | Metal impurity inspection device |
| CN117129539A (en) * | 2023-10-26 | 2023-11-28 | 苏州仁正智探科技有限公司 | Compensation coil system and method for induction type oil wear debris sensor |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85103661A (en) * | 1985-05-18 | 1986-04-10 | 西安交通大学 | The Particle content determinator |
| CN2135152Y (en) * | 1992-09-04 | 1993-06-02 | 中国矿业大学 | Ferromagnetic material detector |
| CN2442269Y (en) * | 2000-09-18 | 2001-08-08 | 宝山钢铁股份有限公司 | One body multifunction roller eddy detection probe |
| CN2462380Y (en) * | 2000-10-08 | 2001-11-28 | 南京大陆中电科技股份有限公司 | On-line smoke and dust turbimeter with automatic calibrating function |
| WO2005010503A1 (en) * | 2003-07-30 | 2005-02-03 | Koninklijke Philips Electronics N.V. | Integrated 1/f noise removal method for a magneto-resistive nano-particle sensor |
| WO2005111596A1 (en) * | 2004-05-18 | 2005-11-24 | Koninklijke Philips Electronics N.V. | Magnetic rotation to improve signal-over-background in biosensing |
| CN1813203A (en) * | 2003-03-11 | 2006-08-02 | R.E.汤普森(真空)有限公司 | Apparatus for detecting the presence of electrically-conductive debris |
| CN101479590A (en) * | 2006-06-28 | 2009-07-08 | 皇家飞利浦电子股份有限公司 | A magnetic sensor device for and a method of sensing magnetic particles |
-
2010
- 2010-05-17 CN CN2010101755547A patent/CN101963570B/en not_active Expired - Fee Related
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85103661A (en) * | 1985-05-18 | 1986-04-10 | 西安交通大学 | The Particle content determinator |
| CN2135152Y (en) * | 1992-09-04 | 1993-06-02 | 中国矿业大学 | Ferromagnetic material detector |
| CN2442269Y (en) * | 2000-09-18 | 2001-08-08 | 宝山钢铁股份有限公司 | One body multifunction roller eddy detection probe |
| CN2462380Y (en) * | 2000-10-08 | 2001-11-28 | 南京大陆中电科技股份有限公司 | On-line smoke and dust turbimeter with automatic calibrating function |
| CN1813203A (en) * | 2003-03-11 | 2006-08-02 | R.E.汤普森(真空)有限公司 | Apparatus for detecting the presence of electrically-conductive debris |
| WO2005010503A1 (en) * | 2003-07-30 | 2005-02-03 | Koninklijke Philips Electronics N.V. | Integrated 1/f noise removal method for a magneto-resistive nano-particle sensor |
| WO2005111596A1 (en) * | 2004-05-18 | 2005-11-24 | Koninklijke Philips Electronics N.V. | Magnetic rotation to improve signal-over-background in biosensing |
| CN101479590A (en) * | 2006-06-28 | 2009-07-08 | 皇家飞利浦电子股份有限公司 | A magnetic sensor device for and a method of sensing magnetic particles |
Non-Patent Citations (1)
| Title |
|---|
| 《润滑与密封》 19931231 王晓雷等 《磨屑定量检测技术的新发展-铁磁颗粒定量仪》 第53-55页 8-9 , 第1期 2 * |
Cited By (40)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103308431A (en) * | 2013-06-05 | 2013-09-18 | 桂林电子科技大学 | Sensor for monitoring metal abrasive particles in oil liquid on line and application method for sensor |
| CN103308431B (en) * | 2013-06-05 | 2015-06-03 | 桂林电子科技大学 | Sensor for monitoring metal abrasive particles in oil liquid on line and application method for sensor |
| CN103344535B (en) * | 2013-06-09 | 2015-04-22 | 桂林电子科技大学 | Oil metal abrasive particles online monitoring system |
| CN103344535A (en) * | 2013-06-09 | 2013-10-09 | 桂林电子科技大学 | Oil metal abrasive particles online monitoring system |
| WO2015010460A1 (en) * | 2013-07-24 | 2015-01-29 | 中国矿业大学 | System for online monitoring metal abrasive grains in oil liquid and monitoring method therefor |
| CN103592208A (en) * | 2013-11-13 | 2014-02-19 | 中国人民解放军国防科学技术大学 | Electromagnetic type oil metal particle monitoring sensor resistant to environmental magnetic field interference |
| CN103684176A (en) * | 2013-12-21 | 2014-03-26 | 西安科技大学 | Device and method for determining rotating speed of motor rotor by residual voltage of motor stator winding |
| CN103684176B (en) * | 2013-12-21 | 2015-11-04 | 西安科技大学 | Utilize the device and method of the residual voltage determination rotor rotating speed of motor stator winding |
| CN103926276A (en) * | 2014-03-25 | 2014-07-16 | 天津大学 | Online oil liquid abrasive particle monitoring device and measuring method |
| CN103926276B (en) * | 2014-03-25 | 2016-01-20 | 天津大学 | A kind of online oil liquid abrasive grain monitoring device and detection method |
| CN104165820A (en) * | 2014-08-19 | 2014-11-26 | 北京华安广通科技发展有限公司 | Sensor for detecting content of ferrum powder in lubricating oil and detecting method |
| CN104539214A (en) * | 2015-01-12 | 2015-04-22 | 深圳市英威腾电气股份有限公司 | Communication circuit used for tracking rotation speed of motor |
| CN105241949A (en) * | 2015-10-16 | 2016-01-13 | 中国航空工业集团公司北京长城航空测控技术研究所 | Detection circuit of grease metal filing online monitor and carrier signal demodulation method |
| CN105241949B (en) * | 2015-10-16 | 2018-09-18 | 中国航空工业集团公司北京长城航空测控技术研究所 | Lubricating oil metal filings monitor the detection circuit and carrier signal demodulation method of device on-line |
| CN105547932A (en) * | 2015-12-08 | 2016-05-04 | 中国航空工业集团公司北京长城航空测控技术研究所 | Engine lubricating oil metal particle on-line monitoring signal demodulation method |
| CN105547932B (en) * | 2015-12-08 | 2018-06-01 | 中国航空工业集团公司北京长城航空测控技术研究所 | A kind of signal demodulator method of motor oil metallic particles on-line monitoring |
| CN105571994B (en) * | 2015-12-11 | 2018-02-09 | 中国航空工业集团公司西安航空计算技术研究所 | A kind of power drive system lubricating oil metal fillings parameter detection method |
| CN105571994A (en) * | 2015-12-11 | 2016-05-11 | 中国航空工业集团公司西安航空计算技术研究所 | Parameter detection method for lubricating oil metal filing of power transmission system |
| CN105865984A (en) * | 2016-05-12 | 2016-08-17 | 绍兴文理学院 | Oil monitoring method based on full-band variable-structure working condition adaptive filtering and molding |
| CN105865986A (en) * | 2016-05-12 | 2016-08-17 | 绍兴文理学院 | Oil monitoring equipment based on full-band variable-structure working condition adaptive filtering and molding |
| CN105891061A (en) * | 2016-05-12 | 2016-08-24 | 绍兴文理学院 | Liquid oil monitoring device adopting full-band and variable-structure filtering, absorbing and shaping |
| CN106483569A (en) * | 2016-12-08 | 2017-03-08 | 华北电力大学（保定） | Balanced differences dynamic formula metal detection sensor and insulation paper detecting apparatus |
| CN106483569B (en) * | 2016-12-08 | 2019-03-15 | 华北电力大学（保定） | Balanced differences dynamic formula metal detection sensor and insulation paper detecting apparatus |
| CN107332535A (en) * | 2017-06-26 | 2017-11-07 | 武汉凡谷电子技术股份有限公司 | It is a kind of to be used to adjust the circuit arrangement that microstrip line transmits phase |
| WO2019109870A1 (en) * | 2017-12-05 | 2019-06-13 | 西人马联合（泉州）科技有限公司 | Magnetic induction particle detection device and concentration detection method |
| CN107907455A (en) * | 2017-12-05 | 2018-04-13 | 西人马（厦门）科技有限公司 | A kind of magnetic induction grain testing apparatus and concentration detection method |
| CN108051348A (en) * | 2017-12-05 | 2018-05-18 | 西人马（厦门）科技有限公司 | A kind of detecting system and method for fluid non-metallic particle concentration |
| CN111433602A (en) * | 2017-12-06 | 2020-07-17 | 昭和电工株式会社 | Method for inspecting lubricating oil composition and method for producing lubricating oil composition |
| CN109283101A (en) * | 2018-11-19 | 2019-01-29 | 北京理工大学 | A kind of high sensitivity wear particle on-line detecting system and method |
| CN109839334A (en) * | 2019-03-12 | 2019-06-04 | 西安交通大学 | Signal recognition method towards unicoil magnetic inductive abrasive grain detection sensor |
| CN109839334B (en) * | 2019-03-12 | 2020-08-14 | 西安交通大学 | Signal identification method for single-coil magnetic induction type abrasive particle detection sensor |
| CN110018094A (en) * | 2019-05-17 | 2019-07-16 | 大连海事大学 | Magnetic core multi-parameter abrasive grain sensing device is set in one kind |
| CN110031373A (en) * | 2019-05-17 | 2019-07-19 | 大连海事大学 | A kind of multi signal synchronous feedback plant of oil liquid detection |
| CN110018094B (en) * | 2019-05-17 | 2022-02-08 | 大连海事大学 | Multi-parameter abrasive particle sensing device with built-in magnetic core |
| CN112014889A (en) * | 2019-05-31 | 2020-12-01 | 株式会社日立大厦系统 | Metal impurity inspection device |
| TWI679412B (en) * | 2019-06-19 | 2019-12-11 | 國立虎尾科技大學 | Detection method of wear debris in lubricating oil |
| CN111721513A (en) * | 2020-06-10 | 2020-09-29 | 山东交通学院 | Analysis method for wear of marine diesel engine |
| CN111721513B (en) * | 2020-06-10 | 2022-04-29 | 山东交通学院 | Analysis method for wear of marine diesel engine |
| CN117129539A (en) * | 2023-10-26 | 2023-11-28 | 苏州仁正智探科技有限公司 | Compensation coil system and method for induction type oil wear debris sensor |
| CN117129539B (en) * | 2023-10-26 | 2023-12-22 | 苏州仁正智探科技有限公司 | Compensation coil system and method for induction type oil wear debris sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101963570B (en) | 2012-08-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101963570B (en) | Device for rapidly detecting ferromagnetic grain in lubricating oil, detection method and signal processing circuit | |
| CN104697905B (en) | A kind of method for designing and oil liquid abrasive grain detection means of oil liquid abrasive grain detection sensor | |
| CN106597351B (en) | A kind of implementation method of pair of electric energy meter checking device on-line real time monitoring | |
| CN108415089B (en) | A kind of oil liquid metallic particles detection device | |
| CN103217365A (en) | Online oil way abrasive particle monitoring device | |
| CN103105120B (en) | Non-contact displacement transducer and non-contact type displacement measurement method | |
| CN103592208A (en) | Electromagnetic type oil metal particle monitoring sensor resistant to environmental magnetic field interference | |
| CN204461949U (en) | A kind of oil liquid abrasive grain pick-up unit | |
| CN201229197Y (en) | Filter arrangement for vortex flow sensor detecting system | |
| CN111157777B (en) | Design method of double-magnetic-core differential leakage current measurement sensor | |
| Xie et al. | A bridge-type inductance sensor with a two-stage filter circuit for high-precision detection of metal debris in the oil | |
| CN108051348A (en) | A kind of detecting system and method for fluid non-metallic particle concentration | |
| CN111639795B (en) | Intelligent inspection task planning method for substation robot | |
| CN202002911U (en) | Intelligent digital eddy current flaw detector | |
| CN201035156Y (en) | Metal detector and its sensor | |
| Li et al. | Online symmetric magnetic excitation monitoring sensor for metal wear debris | |
| Shi et al. | Capacitive–inductive magnetic plug sensor with high adaptability for online debris monitoring | |
| CN109974799A (en) | A kind of self-adaptive electromagnetic flowmeter polarization noise bucking-out system based on feedforward control | |
| CN106885948B (en) | A kind of laser Height-adjusting device capacitance measuring device | |
| CN106093813A (en) | A kind of method of experimental analysis magnetizing mediums monofilament capture | |
| Qian et al. | Wear debris sensor using intermittent excitation for high sensitivity, wide detectable size range, and low heat generation | |
| CN109342805A (en) | A kind of high-precision micro-ampere current detection circuit | |
| CN201041561Y (en) | A novel backset detector | |
| CN109143389B (en) | A kind of three-dimensional industrial frequency interference source for nuclear-magnetism quantifies orienting device and measurement method | |
| CN104834271B (en) | Axle servo parameter optimization method is directly fed based on dynamic stiffness evaluation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120801 |