CN101233385A - Method and device for distance measurement by means of capacitive or inductive sensors - Google Patents
Method and device for distance measurement by means of capacitive or inductive sensors Download PDFInfo
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- CN101233385A CN101233385A CNA2006800278627A CN200680027862A CN101233385A CN 101233385 A CN101233385 A CN 101233385A CN A2006800278627 A CNA2006800278627 A CN A2006800278627A CN 200680027862 A CN200680027862 A CN 200680027862A CN 101233385 A CN101233385 A CN 101233385A
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Abstract
The application relates to a method and device for measuring the propagation time of capacitive or inductive fields.
Description
The cross reference of related application
The application requires the right of priority of the German patent application submitted on July 29th, 2005, on September 27th, 2005 and on Dec 14th, 2005 No. 102005036354.7, No. 102005045993.5 and No. 102005063023.5, therefore, its disclosed content is attached in the application's the theme especially.
Technical field
The present invention relates to that a kind of aforementioned part according to claim 1 and 12 is described to be used for detecting the influence that changes in the field of capacitance field or induction field or the method and apparatus of transit time.
Background technology
In having a taste of, many application need to determine the distance of object of reference with respect to another object.Such application can be the metallic particles that detects in the soil, perhaps can be in automotive field inspected object approaching.
A possibility that detects distance is to measure transmitter in the emission optical radiation, reflect the object of this optical radiation and the light transit time between the receiver.For example, from DE 100 22 054A1, disclose the solution of the form of such light path sensor, wherein, utilized the phase shift that sends and receive between the light for measuring distance.Therefore, the received signal with minimum amplitude is provided for synchronous rectifier with the voltage of oscillator.Therefore, the signal that generates with pure electricity from the detection signal of light path is provided for the input end of synchronous rectifier.The output signal of the input end by appearing at synchronous rectifier is adjusted input signal, until when prefix sign is changed, is approximately zero at the mean value of two signals of output terminal.Simultaneously, the task of synchronous rectifier is the phase place of measured signal very accurately.The delay, burn-in effects and the temperature effect that with the assembly are precondition are connected each other individually and are compensated.Even when using reference path, realize control by influencing delay element incoming call ground.Therefore, phase shift 90 degree or the photodiode signal of 270 degree and the signal of pure electrical transmission are provided for traditional synchronous rectifier, in order to carry out phase measurement.For this reason, it is for such purpose that these signals before the arrival synchronous rectifier are not equal to zero, promptly keeps each signal segment of received signal isometric.
In addition, in WO 01/90778 A1, disclose a kind of method, wherein, controlled the signal of emission and the received signal that on receiver, exists with identical time clock by measurement transit time measuring distance.The control signal of Ce Dinging is come phase shift in this wise by phase shifter like this, promptly being minimized to the distance of target object and the range deviation between the actual range of determining by the measurement transit time.Purpose is to utilize the transit time to optimize sampling spot when high frequency.
By known among EP 706648 B1, under the situation of the influence, Temperature Influence or the burn-in effects that compensate all like parasitic lights, sensed light signal between optical transmitting set and optical receiver.Optical transmitting set is by clock signal generator time interval ground or alternately driving.Perhaps, the light of adjusting in the amplitude of at least one light path together acts on optical receiver in this wise with the light of all like compensatory lights, and promptly received signal does not produce the clock sync signal component.The received signal of optical receiver is transferred to synchronous demodulator, and this synchronous demodulator splits into component of signal corresponding to two light sources once more with received signal.These two component of signals compare in comparer each other, wherein, do not produce the parasitic light part corresponding to the signal of zero state.If not corresponding to the signal of zero state, the radiation power that is transported to light source so is conditioned until reaching this state at the output terminal of comparer.
Possibility as the measurement of light transit time (this measurement is impossible when the opaque medium for optical radiation especially), when the variation that can detect electric field and/or capacitance field, this variation by the object of influence close, exist and/or away from drawing.Know that by experiment the pulse (producing electric charge or variation inductance in these) that causes these variations is with light velocity propagation, and the variation itself of rising such as image charge realizes more slowly in time.
Summary of the invention
Based on the prior art state, the object of the present invention is to provide a kind of capacitance field and/or the influence of inductive fields or optional method of transit time that is used to measure on capacitance path and/or the inductance path.
The method of the feature of this purpose by having claim 1 and the device with feature of claim 12 are realized.
Decide according to detection electric capacity or inductance, select electrode or coil as radiated element and receiver, electrode or coil be by the electric capacity in its neighboring area and inductive impact or by the object influence, this object electric capacity or influence and then influence metering circuit inductively.Certainly, also can use other the device that is used to produce and measure electric field and/or magnetic field.Therefore, also can be used to an influence or the transit time that changes that measurement field when the situation of electric capacity or inductive fields changes by the principle of disclosed optical balance among EP 706648 B1.
From at least two to produce or the clock signal of the element of electrode that the launching site changes or coil form is fed to receiver.Then, capacitor shown in Figure 1 is corresponding to two electrodes of the spacing with definition.In the situation of the solution of electric capacity, the electric field that makes up by the electric charge that is applied on the electrode for example changes by object to be detected.This causes change in charge on electrode, and it is measured once more, thereby determines the distance/influence of object.The field of capacitance field changes by receiver to be measured, and this receiver is coupled to emitting electrode.Realize compensation by capacitor, with emitting electrode with also to constitute one type the object of capacitor thus different, this capacitor has known spacing between its face.The field changes also from capacitor arrival receiver.Received signal and be compared to each other and be adjusted to minimum each other possible difference by amplitude modulator and phase regulator from the changing value of two measuring route.Then, the regulated value of amplitude modulator or phase regulator is corresponding to the value of electric capacity or transit time, and this regulated value is necessary for constituting electric field line.
For this reason, come the received signal of the clock period of self-emission electrode and compensating electrode approximately to be divided into four identical segments in a preferred manner., and represent that Segment A and C compare and utilize the phase shift process will be adjusted to as far as possible little difference each other so the turn-on time of compensating electrode if represent with Segment A and B the turn-on time of reflecting electrode with C and D.Equally, fragment B and D utilize the amplitude adjustment process will be adjusted to as far as possible little difference each other.In Segment A and C, comprise the information of transit time, and in fragment B and D, comprise the direct capacitance of field or the information of static influence.Then, can measure transit time and the distance between electrode and object or receiver that the field in capacitance field changes by the delay of phase shifter.In the situation of the solution of inductance, only replace emitting electrode and compensating electrode basically by coil and compensating coil, wherein, receiver also can be designed to receiving coil.
Compensation process can be eliminated the component of signal of clock synchronization fully, that is to say only to keep actual amplifier noise.Therefore, amplifier can have higher amplification coefficient or can even be designed to the limiting amplifier of high amplification coefficient.
Thus, the time clock alternating signal that occurs when the time clock alternation is detected and determined by the minimized difference of phase shifter by this signal.Influence that is changed by the field that can determine in the signal delay that causes by phase shifter in capacitance field and/or inductive fields or transit time also and then are determined distance between transmitter and object or receiver.Transit time, the high amplification coefficient by received signal clearly was rendered as the time clock alternation time voltage peak.This peak value the element of reflection just in the time clock separately of emitting electrode and compensating electrode (the nearest circuit on the comparer place decide) two input ends of comparer to occur and to arrive with respect to the different polarity of noise, these two input ends are suitably switching with synchronous clock frequency in the time cycle accordingly.The amplitude of this time clock alternating signal depends on a transit time, yet, this only is because be related to minimizing of difference, the difference of signal can be in the amplitude from the time clock to the time clock time clock synchronously the difference of demodulation and existence can time clock synchronously in amplitude the difference of demodulation and existence be used to control phase shifter and be used for this difference is compensated for as zero.Because time clock, the time point of time clock alternation is known, thereby in this time point detection peak only.Simultaneously, can utilize arbitrarily time clock to come work.
Pass through the adjustment circuit of two closures of amplitude modulator on the one hand, reach following advantage by the transit time adjusting on the other hand:
-very high sensitivity
-even the good transit time on closely (until " 0 " distance) measure
-in the detection of transit time, there is not temperature effect
-not strict in the change of amplifier parameter
The attribute of-object does not influence range observation
Other advantages are by drawing in ensuing description and other the claim.
Description of drawings
Next, the embodiment in reference to the accompanying drawings further describes the present invention.Shown in the figure:
Fig. 1 is used to measure at the influence of capacitance field midfield variation or the circuit diagram in a circuit according to the invention of transit time,
Fig. 2 be on the receiver of Fig. 1 under be divided into the signal of the reception in the zones of different,
Fig. 3 is the signal according to the top part of Fig. 2 after using phase shifter,
Fig. 4 shows from the receiver place signal waveform that has and do not have the measuring route of detective path idealizedly,
Fig. 5 shows in the synthetic field at receiver place idealizedly and gets over time clock,
Fig. 6 exemplarily shows the pulse of Fig. 5
Fig. 7 is the pulse by Fig. 6 of receiver and amplifier,
Fig. 8 is used for measuring in the influence of the field of induction field variation or the schematic circuit in a circuit according to the invention of transit time.
Embodiment
With reference now to accompanying drawing, exemplarily further specifies the present invention.Yet embodiment only is an example, and it also is not used in the invention theory is defined in specific scheme.
Before describing the present invention in detail, be noted that each assembly or each method step that are not limited to circuit here, this is because these assemblies and method can change.Here the notion of Ying Yonging only is used to describe certain embodiments, but is not limited thereto.In addition, when using odd number or indefinite article in instructions and claim, only otherwise make whole relation refer to other element clearly, they also relate to the plural number of these elements.
The present invention can realize range observation, and it allow to utilize the measurement of the accurate transit time that amplifier with narrow bandwidth changes the field in capacitance field and/or the inductive fields, and this measurement is not subjected to surrounding environment influence and does not rely on the material behavior of object.In addition, can under the situation of handover measurement scope not, be implemented in from electrode surface or coil surface begin closely only to the measurement of transit time of big distance.
The present invention is based on following consideration:
When the variation that can detect capacitance field or variation inductance (its can draw influence object close, exist and/or away from conclusion) time can realize range observation because field electric capacity or inductance in field electric capacity and/or inductance changes.
This will describe with the situation of the solution of electric capacity: the electrode 12 clock controls ground that together constitutes capacitor with object O obtains as emission or produces the charged particle of the element of first variation, and the effect of this charged particle exerts an influence in the environment around.The electric charge that this clock control ground applies with the form of potential pulse by object O close, exist or away from influencing.This influence is not to realize at once, but realizes with light propagation delay ground.Change can be obtained and in amplifier 23 in conjunction with and collect by electrode.If object O is in the sensor zone of action 14 now, that is to say, if object reaches detection path between radiated element and object (for example 15cm distance), dynamically change by receiver reception as the element that is connected with the radiated element effect by detected of device.From the angle of theory, the field change information that is returned by object presents a light transit time with respect to emission information, that is to say, presents the time delay of about 1ns when 15cm.Time difference at first separates with the pulse information of reality.For this reason, the transponder pulse that is used for compensating electrode 21 is activated at pulse interval (Pulspause), and this compensating electrode directly receives its variation, and does not need circuitous object.Certainly, compensating electrode also can influence each other with object, but important only be can influence at least one by object to detect path.Arrive lead 40 if having two signal power S1, the S2 according to Fig. 4 of identical amplitude (this amplitude certainly keeps identical size by the amplitude modulator of electrode 12,21), DC voltage appears in input end 23a at amplifier 23 basically so, and this DC voltage is made of voltage signal and possible being misplaced from two charge carriers alternately.
When finer observation, the transit time difference of 1ns is added to the d. c. voltage signal at amplifier 23 places in the exomonental transition of two electrodes outward.A stage, on the pent point of compensating electrode 21, in the d. c. voltage signal of alternating signals waveform, produce the gap, but the change in charge pulse of emitting electrode 12 must arrive object through the distance of 15cm and return.In subordinate phase, compensating electrode 21 is transmission charge, although and from the charge pulse of the emitting electrode 12 of closing at correct time point also on the way.This schematically shows in Fig. 5.In received signal, this causes the very short peak value of phase locked alter polarity in an embodiment.This time difference is very little for receiver, thereby this time difference is occurred as just very little electric current changing value when the low-pass characteristic of for example 200KHz.
Therefore, applied energy law of conservation: suppose, only the electrode 12 that outwards points to towards the object O electrode 21 that receives with clock frequency or collect electric charge and be used for comparison is closed, an AC signal arrives amplifier 23 then, this AC signal illustrates as voltage, for example the alternating voltage of the 10mV that obtains on the output terminal 23b of alternating voltage amplifier arbitrarily.If we are starting point with desirable receiver and desirable amplifier with desirable rise time characteristic, we will continue to suppose that under the situation of emitting electrode the output signal with 10mV with 50% duty factor is a starting point so.If connect second electrode, because of the transit time of signal, time clock synchronously alternately draws the pulse (Fig. 5) of 1ns on positive dirction and negative direction so.Then, in described situation, these pulses are unique information in amplifying signal and the information of representing the transit time.Yet in practice, " low-pass characteristic " of receiver and amplifier will " be engulfed " this short especially pulse.
At this, advantage according to the system that regulates with amplitude of the present invention begins to work: because be present in amplifier 23 places (this amplifier 23 for example is made of the third stage amplifier of the bandwidth with 200KHz) as just the short pulse of change information, so received signal can almost at random be amplified, for example amplify with 10,000 times amplification coefficient.Although the 1ns on first amplifier out is long and in the ideal case the theoretic change pulse of 10mV only cause for example strong voltage swing (Fig. 6 illustrates) of 10 μ V in practice, length t1 is the signal of the 100mV of 5 μ s to this voltage swing through for example obtaining having after 10,000 times the amplification in other amplifier stage (Fig. 7) now.At this, pair amplifier does not have special requirement, and the bandwidth of 200KHz is enough for corresponding amplification.Although can use amplifier arbitrarily, preferably use alternating voltage amplifier.After an electrode switches to another, present signal with the direction (positive and negative) that replaces after the point in switching time.Come to detect the synchronous component of signal of the signal that receives with respect to this time point by the rectifier of synchronously connecting with clock frequency.Because the component of signal that transit time difference causes also can detect in strong noise signal without a doubt by the component of signal of integrating synchronously demodulation simply.What need mention is, synchronous rectifier or synchronous demodulator D1, D2 are not the circuit that must accurately detect phase place, but the circuit of clock control ground detected amplitude.The accuracy of phase place is to not influence of measurement precision, thereby for example 20 ° phase shift also is inessential.
Because the appearance of the component of signal of this clock synchronization has been pointed out the transit time difference between two electrodes 12,21 and has also been allowed relation clearly with respect to electrode in addition, so the adjustment circuit according to Fig. 1 (seeing below) utilizes this information closure in this wise, promptly as by the electric charge of object influence, compensating electrode 21 utilizes the means known transit time of adjustable all pass network or phase in-migration adjustment that can be digital regulated (for example by) with identical value phase shift.Then, the passing that is used for necessity of the electric control pulse that the phase shifter 17 (Fig. 1) of electrode 21 locates is influence that the field on capacitance field is changed or the direct measurement of transit time and also is to the effect of object O or the direct measurement of distance.
Certainly, after synchronously demodulation depends on the component of signal of transit time, in order reciprocally to be adjusted to " 0 ", the phase shift that two component of signals can be by electrode 21 for example is compared to each other in other the operational amplifier of high amplification coefficient, and bandwidth is not had special requirement.Then, if there is very little difference between the component of signal of two clock synchronizations, this difference is adjusted into " 0 " by phase adjusted so.
In an embodiment, below Fig. 1, use two different adjustment circuit simultaneously.On the one hand, be adjusted to identical value at the input end of amplifier 23 by the amplitude control procedure in two known in EP 706648 B1 electrodes at least one from the amplitude that receives of two charge paths.Because switch at least another electrode from least one electrode after, prolong consumingly as the length that differs of amplitude information, so when transit time during information attenuation, should be at first in the transit time difference of the clock synchronization of a time point detection signal.In practice, for example approximately the clock frequency of 100KHz-200KHz is proved to be suitable, wherein, in the first of clock period, the transit time difference of detection signal before control phase, this transit time difference occurs as the amplitude in signal, and detects net amplitude difference in the second portion of clock period.Then, utilize the information of second semiperiod of clock period, at least one electrode in two electrodes in an embodiment only influences amplitude by amplitude modulator 18, thereby obtains from the signal of the same size in two paths and thus difference is adjusted to zero.The signal of the identical size in two paths causes not having the zero-signal of the alternating component of clock synchronization.
Certainly, the phase place of direct acting electrode 21 not necessarily must be mated corresponding to the electrode 12 by the influence of transit time constraint.In corresponding circuit, also can be affected by the electrode of the influence constraint of transit time.
Owing to " 0 clock synchronization " component that amplitude is regulated, the transit time is adjusted to, realized the described advantage of beginning by the adjustment circuit of these two closures.
With reference to figure 1, in device according to the present invention, electric charge flows to amplifier 23 by second path 20 and lead 40 from electrode 21.Method is used for measuring the transit time that changes in the field of capacitance field (Fig. 1) and/or inductive fields (Fig. 8).At first, when 200KHz for example, be incorporated into the sensor zone of action 14 by lead 30,31 and through electrode 12 from output terminal 11E by the electric charge of clock impulse controller 11 modulation.Charge affects electrode, i.e. electric field on every side between electrode and object O.This influence realizes with the light velocity.Yet when identical clock frequency, anti-phase by phase inverter 22 also produces electric charge on the electrode 21 of electrode by way of compensation, and its electric charge is the received signal of clock control ground influence on amplifier 23 also.For this reason, electric charge arrives the input end 17a of phase shifter 17 by lead 30,33 and passes through the output terminal 17b of phase shifter and the input end 22a that lead 34 arrives phase inverters 22 with the clock frequency of clock impulse controller 11, and electric charge arrives the input end 18a of amplitude modulator by lead 35 from the output terminal 22b of this phase inverter.Electric charge leads to electrode 21 from amplitude modulator 18 by output terminal 18b.
Thus, signal S13 from two electrodes alternately passes through lead 20 by lead 32,40 in one case in another case with the clock frequency of clock impulse controller 11,40 appear at the input end 23a place of amplifier 23, this signal since first or the cause that changes of other field as first changing value or second changing value.Signal S13 leads to amplifier 23 by lead 40 and amplify and flow to by lead 41 then synchronous demodulator D1, the D2 of two structural similarities with the comparer 15 that illustrates and 16 in amplifier below Fig. 1.The task of synchronous demodulator D1, D2 is not accurately to measure phase place, but amplitude is measured on clock control ground.Phase accuracy is to not influence of measurement precision, thereby for example 20 ° phase shift also is inessential.
Before further inquiring into this circuit, show as the signal after amplifier 23 on the top of Fig. 2.Shown signal does not show a signal waveform, when for example appearing at from last transit time of the distance of electrode 12 and 21 to the 15cm of object just as this signal waveform and not conditioning signal phase place the path, a field in path, two fields.The appearance of the component of signal of clock synchronization can utilize corresponding gate circuit to detect and distribute to corresponding electrode.At this, directly after the switching of clock frequency, distinguishing between the amplitude difference on the whole clock ranges and between the signal amplitude.For this reason, the clock period is dividing in four fragments of A/B/C/D among Fig. 2.Fragment B, D represent amplitude, and this amplitude does not have the synchronous amplitude difference of time clock in adjusted state, that is to say, time clock is identical.The adjusted state of fragment B, D relates to the amplitude of two at least one electrodes in the electrode and regulates.In the fragment B of clock control and D, amplitude is adjusted in the state of identical value, from identical transit time of two electrodes the time, has the signal of the component of signal that does not have clock synchronization.Only present the component of signal of clock synchronization, but this component of signal drops among Segment A and the C at the signal of other electrode 21 with from the transit time difference different time between the signal that detects the path.
In Fig. 1, synchronous demodulator D1 and D2 with comparer are controlled by output terminal 11A, 11B, 11C and 11D and affiliated clock lead 50A, 50B, 50C and 50D in this wise by clock impulse controller 11, the amplitude modulator 18 of the clock synchronization component that is synchronous demodulator D1 by being used for being adjusted in amplifier 23 places is adjusted into " 0 " with the clock synchronization amplitude difference of the changing value of the signal S13 that receives, and the transit time difference between the synchronous demodulator D2 detection signal and the clock synchronization component at amplifier 23 places is adjusted into " 0 " by phase shifter.When unadjusted transit time, in the Segment A of clock control and C, exist from the phase place to phase place ground to change the clock sync signal component of polarity, this clock sync signal component flows to conditioning signal S16 at the output terminal of synchronous demodulator D2, this conditioning signal is controlled phase shifter 17 conversely in this wise, promptly has " 0 " signal that does not have the clock sync signal component on the output terminal 23b of amplifier 23.
In synchronous demodulator D1, the signal S13 that receives just changing value resolves into two part signals of electrode 12 and another electrode 21 again.For this reason, signal arrives the switch corresponding to fragment B and D by lead 41,41B, 41D, and this switch is handled with the time clock conversion ratio of fragment B and D by clock impulse controller 11 by clock lead 50B and 50D.Therefore,, appear on lead 60B and the 60D, by collecting this changing value in the detection that is perhaps influenced by object on receiver with the signal of fragment B and the corresponding changing value of D corresponding to the position of the switch of the output of switch.These signals are transported to input end 15a, the 15b of comparer 15 by integrator R3, R4 and/or C3, C4, when the signal of identical size, the control signal corresponding of the zero state of signal S13 occurs being used on its output terminal 15c.If other signals appear in the there, control signal arbitrarily as signal S15 appears on the input end 18c of amplitude modulator 18 by lead 70 so, this amplitude modulator is adjusted the amplitude of other electrode 21 in this wise again, be that signal S13 becomes the signal corresponding to zero state, therefore that is to say, comprise no clock synchronization component and do not need other in adjustment process.In this state, the changing unit of clock synchronization be eliminated and thus regulated value 94 comprise information about thingness, and regulated value 93 comprises the information about the distance of object.In the drawings, the amplitude of another charge carrier 21 is adjusted again, still, this adjustment process can certainly as same purpose disclosed among EP 706648 B1 on electrode 12 or two or act in the situation at a plurality of radiated elements a plurality of on.
In other words, the synchronous demodulator D1 that is used for the amplitude detecting of beat-type is employed, and at its input end, has just preferably had the signal from the no clock synchronization component in two paths on corresponding to the switch of fragment B and D.From the zero-signal that keeps, on the output terminal of the amplitude detector of synchronous demodulator D2 form, detect the time clock alternating signal TW in noise.
In the scope of phase transformation of the sample period on clock lead 50A, 50B, 50C, the 50D, adjust the distance and measure not influence at broad.With respect to the high precision of the phase place of needed synchronous demodulator among DE 100 22 054 A1, according to range observation of the present invention needs not.Still be essential to the sampling of amplitude just at the approximate time point of clock frequency.Therefore, synchronous demodulation process only is accurate synchronous demodulation process according to the present invention.Phase place itself is for the difference of the amplitude of identification time clock alternating signal and to make clock synchronization component at the input end of the amplitude detector of synchronous demodulator D1 type be zero meaningless.Then, the phase in-migration of this time clock alternating signal by the signal that exists in the device between electrode 12 and 21 minimizes each other and preferably becomes zero.The delay of thus obtained phase shifter 17 is a transit time that changes and the distance to be determined of object O.
At Fig. 1 middle part, two upper switches of synchronous demodulator D2 are by corresponding to controlling according to the regional A of the top part of Fig. 2 and the gate circuit of C.In synchronous demodulator D2, signal S13 that receives and changing value are equally corresponding to the amplitude signal of two electrodes 12 and 21, and be certain also corresponding to the component of signal corresponding to Segment A and C.For this reason, signal arrives the switch corresponding to Segment A and C by lead 41,41A, 41C, and these switches are handled with the time clock conversion ratio of Segment A and C by clock impulse controller 11 by clock lead 50A and 50C.Therefore, corresponding to the position of the switch, the output terminal that appears at switch at lead 60A and the signal on the 60C corresponding to Segment A and C.These signals are transported to input end 16a, the 16b of comparer 16 by integrator R3, R4 and/or C3, C4.
Therefore, occur with the time clock conversion ratio, change and any other field changes and detected by the mode with clock control corresponding to first of the transit time in the detection path in the sensor zone of action 14.Although the size of the amplitude of signal depends on object O, because relate to the difference of the clock synchronization between these two signals here, so this is unessential.These two signals compare in other comparer 16.The difference on the output terminal 16c of comparer corresponding to first and other field between changing differ and owing to the integration in receiver changes into amplitude.Can take a sample to this value at time point arbitrarily, this arbitrarily time point no longer have phase information.Non-phase place is accurately coordinated that is to say non-accurately in phase boundary adaptive amplitude arrive the input end 17c of phase shifter 17 as signal S16 and in phase shifter 17, change in this wise, minimum and be preferably zero up to this value, thus determine the transit time that the field in capacitance field and/or inductive fields changes thus.The delay of this setting, can determine the transit time and determine distance thus that from phase shifter 17 this is apart from the output terminal 17d that appears at phase shifter 17 as the signal that is used for the transit time 93.According to Fig. 3, by the variation of phase shifter 17, the amplitude of time clock alternating signal TW disappears in noise.
If the sensor zone of action 14 with measurement face with the form of high ohm in this wise by impedance Z 1 and Z2 be coupled to lead 31 and 32 or by impedance Z 3 and Z4 be coupled to lead 36 and 20 and and then be coupled on driver and the amplifier 23, promptly even can perceive the minimum change of the form of in environment amplitude on measurement face and/or phase change.Simultaneously, amplifier circuit is coupled on the measurement face in this wise high ohm, promptly influences the amplitude and/or the phase place of measuring-signal whereby fully or rarely.In an embodiment, be coupled and preferably realize, yet also can use the combination or the single parts of coil or above-mentioned parts for this purpose by capacitor and resistance.In an embodiment, the series circuit that is made of the driving voltage of 10pF and clock frequency 50 KO, 100KHz and 2 volts uses as impedance Z.Preferably, the coupling of high ohm identically designs with respect to driver and amplifier 23 are similar big or smallly, and this is the combination realization of capacitor, resistance, coil or the said modules by identical size in an embodiment.
Little electric capacity by capacitor or high resistance or high inductance (in an embodiment) obtain from measurement face to electrode 12, to the high impedance of output stage and 23 expection from measurement face to amplifier.Therefore, be connected with in a circuit according to the invention reference potential by the electrical connection of air electric capacity and other types as object O.In Fig. 1, this represents by ground connection shown in broken lines 19.Even in measuring the very near scope of face, be connected also the not sensitivity of EVAC (Evacuation Network Computer Model) with the metallic conduction of the reference potential of circuit.The reason of regulating power owing to pre-amplification and the height of synchronous demodulator D1 with comparer and D2 also can detect minimum variation without a doubt.
Fig. 8 shows optional embodiment of the present invention, and this embodiment allows to be used to detect the measurement of the transit time that the field as the result of the inductance that changes changes.The embodiment district of Fig. 8 is basically by using coil to replace electrode to be different from embodiment among Fig. 1.Thus, when the notion electrode replaces by coil there, below Fig. 8 2/3rds in circuit and use also consistent with the description so far among Fig. 1.The sensor zone of action that is to say that circuit (making progress from this reference identification) and the surveyed area before amplifier 23 after amplitude modulator 18 and lead 31 changes in Fig. 8.Thus, under possible situation, also used identical reference identification.
Clock impulse controller 11 is by output terminal 11E and through lead 31 with impedance Z 2 and the 32 other coil 121 conveying electric currents that use of coil by way of compensation mutually.Electric current arrives coils 112 from its output terminal 18b through lead 37 and the 36 clock frequency anti-phase ground corresponding to clock impulse controller 11 with middle impedance Z 1 that is connected with amplitude modulator 18 by phase shifter 17.Coil 112,121 is connected to ground connection 39 by lead 38.The current signal of such clock control is received, is reflected and pass to input end 23a, the 23a ' of amplifier 23 by receiving coil 113.Then, begin to carry out aforesaid amplitude and phase place adjustment from output terminal 23b.If two coils 112 have identical induction (perhaps after adjusting by amplitude modulator 18) with 121, on the output terminal 23b of amplifier 23, there is signal corresponding to zero state.When in the external magnetic field of coil 112 and 121 in the sensor zone of action 14 when mobile, also obtain this controlled state.But, if one when for example being imbedded in underground metal object and being among the sensor zone of action, this object changes the induction of coil 112, and is not affected in an embodiment as the coil 112 of reference coil.This variation will be detected and assessment by receiving coil 113 clock controls ground as changing value.Also show effect at this, variation on the spot is with light velocity propagation, thereby can determine the distance as the object O of signal 93 as previously described like that from the phase place of time clock alternating signal is adjusted.Simultaneously, signal 94 provides about the quality of object or the information of vortex flow attribute.Certainly, especially under the situation of the solution of inductance, field in addition changes and also can appear on the electron path with the form of voltage signal, and does not need the using compensation element.
Advantageously, also can at random select clock frequency in the present invention, this clock frequency can adopt from the arbitrary value of clock period to another clock period.Interference when being suppressed in parallel system that use and can not be synchronous also can be used arbitrarily " frequency modulation " (FDMA) without a doubt.Therefore, this system not only is suitable for realizing the transit time measuring route in simple mode, also is suitable for realizing a plurality of parallel measuring route.
The element of corresponding device is by drawing in the explanation before, by it with reference to figure 1 and Fig. 8.
Certainly, this description goes for different variants, variation and modification, and it drops in the equivalency range of dependent claims.
Reference number
11 clock impulse controllers
11A、11E
11B, 11C, 11D output
12 electrodes
The 14 sensor zones of action
15 comparators
15a, 15b input
The 15c output
The signal of S15 after comparator
16 other comparers
16a, 16b input end
The 16c output terminal
The difference of S16 after comparer 16
17 phase shifters
17a, 17c input lead
17b, 17d output lead
18 amplitude modulators
18a, 18c input end
The 18b output terminal
The electromotive force of 19 O
20 leads
21 other electrodes
The 21a input end
22 phase inverters
The 22a input end
The 22b output terminal
23 amplifiers
The 23a input end
The 23b output terminal
D1, D2 synchronous demodulator
The O object
R1-R4, C1-C4 integrator
TW time clock alternating signal
Z1, Z2, Z3, Z4 impedance
The 30-38 lead
39 ground connection
40,41 leads
41A, 41B, 41C, 41D lead
50A, 50B, 50C, 50D clock lead
60A, 60B, 60C, 60D clock lead
70,80 leads
93 signal transit times
94 signal reflexs/quality
112 coils
113 other coils
121 other coils
Claims (20)
1. influence or a capacitance field and/or method of inductive fields transit time that is used to measure capacitance field and/or inductive fields has following steps:
-produce by first capacitive field change clock impulse controller (11) clock control, regularly and/or inductive fields variation by at least one element that in the sensor zone of action (14), produces first variation,
-detecting described first variation that perhaps influences by at least one receiver by object (O), described receiver is connected with the radiated element effect, and measures first changing value,
-pass through at least one to produce at least one other capacitive field change and/or the inductive fields variation of the other element that changes generation by the timing of described clock impulse controller (11) clock control,
-detecting the described other field that perhaps influences by described at least one receiver to change by described object (O), described at least one receiver is connected with described radiated element effect, and determines other changing value,
-wherein, by described receiver detect described at least one change, described first and/or described other field of promptly described capacitance field and/or inductive fields changes can be by close, the existence of described object (O) and/or away from influence,
-in the mode of clock control described first changing value and described other changing value are compared, thus on the output terminal of comparer (15), produce fiducial value,
Described comparer be used for adjusting in this wise generation described first change and/or
The amplitude that described other field changes is promptly caused by described first variation
The amplitude of described first changing value and change cause described by described other field
The amplitude of other changing value is basic identical,
-adjust to each other under the situation of basic identical size at the input end of described comparer (15) in the size of described these changing values, clock control ground detect by described first and described other field change the time clock alternating signal (TW) of the transit time that the field of influence between described these changing values that cause, that occur during at the time clock alternation, that change corresponding to the field of described capacitance field or described inductive fields or described capacitance field or described inductive fields changes
-determine difference (S16) by the amplitude of more described these time clock alternating signals (TW) in another comparer (16),
-change the difference (S16) of described time clock alternating signal (TW) by phase shifter (17), up to described difference (S16) minimum, be preferably zero, described phase shifter is used to change the phase delay of the phase place that described first and/or described other field of generation change, its cause on described receiver by described first and described other field change the changing value that causes
-use the delay of the described phase shifter when the difference of minimum, occur, be used for determining close, the influence or the transit time that exist and/or change away from the electric capacity or the inductance of described capacitance field that causes and/or inductive fields by the described object (O) of influence.
2. method according to claim 1, it is characterized in that, when based on described first and described these changing values of changing of described other field same when big at the input end of described comparer (15), only exist at the output terminal of amplifier (23) not have the noise that changes the alternating component of the clock synchronization that causes by described.
3. method according to claim 1 and 2, it is characterized in that, although the noise when on the input end of described comparer (15), the size of described changing value being adjusted to essentially identical value, described first change and described other field changes or described other field changes and described first variation between the clock control of amplitude of the described time clock alternating signal (TW) that occurs when being implemented in the time clock alternation detect.
4. according to each described method in the aforementioned claim, it is characterized in that, described time clock alternating signal (TW) with the prefix alternate in sign detects by gate circuit, and is used for determining phase delay as the described difference (S16) between the described time clock alternating signal (TW) of the control variable of adjusting circuit.
5. according to each described method in the aforementioned claim, it is characterized in that the path is coupled by AC, wherein the described changing value of being measured by the received signal of described receiver comes from described path.
6. according to each described method in the aforementioned claim, it is characterized in that, change the transit time that causes in order to measure by described first and described other field at described receiver place, measure amplitude afterwards at the described radiated element of switching (12,21), and utilize described phase shifter (17) that described amplitude is adjusted to zero.
7. method according to claim 6 is characterized in that, this appearance, the amplitude of described time clock alternating signal (TW) adjusted to each other zero phase shift distance corresponding to described object (O).
8. according to each described method in the aforementioned claim, it is characterized in that, change the changing value at described receiver place (S13) that causes by described first with described other field and be divided into different zone (A, B, C, D), wherein, by means of the gate circuit that moves with the clock frequency of described clock impulse controller (11), application is positioned at the zone (B, D) between the described zone (A, C) that the time clock alternation fallen into, thereby produces fiducial value on the output terminal of described comparer (15).
9. according to each described method in the aforementioned claim, it is characterized in that, be divided into different zone (A, B, C, D) by described first changing value at described receiver place (S13) that causes with described other field variation, wherein, by means of the gate circuit that moves with the clock frequency of described clock impulse controller (11), be applied in the described zone (A, C) that time clock alternation is wherein fallen into, to be used for more described changing value on the output terminal of described comparer (16), to produce described difference (S16).
10. according to Claim 8 or 9 described methods, it is characterized in that the signal of measuring is used for measuring distance in the described zone of described time clock alternation (A, C).
11. according to each described method in the aforementioned claim, it is characterized in that, described changing value is the impedance variation of the parts that use as described radiated element with as described receiver, and described changing value is preferably by described electrode (12,21) and coil (113,112,121) formation.
12. influence or a capacitance field and/or the device of inductive fields transit time that is used to measure capacitance field and/or inductive fields has:
-clock impulse controller (11),
-at least one radiated element is used for producing by capacitive field change described clock impulse controller (11) clock control, regularly and/or inductive fields variation in the described sensor zone of action (14),
-be used to produce at least one by the other capacitive field change of the timing of described clock impulse controller (11) clock control and/or the device of inductive fields variation,
-at least one receiver, be connected with the radiated element effect, being used for detecting described first and the described other field that are perhaps influenced by object (O) changes, wherein, at least one is changed by the field that described receiver detects, be that described first and/or other field of described capacitance field and/or inductive fields change can be by close, the existence of described object (O) and/or away from influence
-be used for measuring at described receiver place by described first and described other field change the device of the changing value that causes,
-comparer (15) is used for clock control ground described first changing value and other changing value is compared, on the output terminal of described comparer, producing fiducial value,
-amplitude modulator (18), described amplitude modulator uses described fiducial value in this wise for the amplitude that first and/or the other field of adjusting generation changes, promptly the amplitude of the described changing value that is caused by described first variation and the amplitude that changes the described changing value that causes by described other field are equal to each other basically
-be used for adjusting to each other under the situation of basic identical size at the input end of described comparer (15) in the size of described changing value, clock control ground detects by described first and the influence that occur when changing between the described changing value that causes, at the time clock alternation, that change corresponding to the field of described capacitance field or described inductive fields of described other field or the device of the time clock alternating signal of transit time (TW)
-other comparer (16) is used for coming clock control ground to determine difference (S16) by the amplitude of more described time clock alternating signal (TW),
-phase shifter (17), be used to change the difference (S16) of described time clock alternating signal (TW), up to described difference (S16) minimum, be preferably zero, described phase shifter is used to change described first and/or the phase delay of the phase place that changes of described other field, its cause on described receiver by described first and described other field change the changing value that causes.
13. device according to claim 12 is characterized in that, described comparer (15) is the synchronous demodulator (D1) that is used for amplitude detecting or the part of gate circuit.
14. according to claim 12 or 13 described devices, it is characterized in that, when by described first with to change the described changing value that causes same when big at the input end of described comparer (15) in described other field, only there is the noise of alternating component at the output terminal of amplifier (23) with clock synchronization.
15. according to each described device in the claim 12 to 14, it is characterized in that, the device that is used for detecting described time clock alternating signal (TW) in clock control ground is a gate circuit, described gate circuit detects the described time clock alternating signal (TW) with the prefix alternate, and the described difference (S16) between described time clock alternating signal (TW) is used as the control variable of regulating circuit.
16. according to each described device in the claim 12 to 15, it is characterized in that, be provided with the device that is used for described changing value (S13) is divided into different zones (A, B, C, D), wherein, gate circuit is set up as being used for the device that clock control ground detects the zone (B, D) between the zone (A, C) that is in the time clock alternation.
17. according to each described device in the claim 12 to 16, it is characterized in that, be provided with the device that is used for described changing value (S13) is divided into different zones (A, B, C, D), wherein, by means of the gate circuit that moves with the clock frequency of described clock impulse controller (11), application region (A, C) is used for more described changing value to produce described difference (S16) on the output terminal of described comparer (16).
18. according to each described device in the claim 12 to 17, it is characterized in that, be provided with at least one and be used to detect the electric capacity of described capacitance field or described inductive fields or the detection path that inductance changes in the sensor zone of action (14), described detection path is formed between described radiated element and the described receiver.
19., it is characterized in that described radiated element is electrode (12) or coil (112,121) according to each described device in the claim 12 to 18.
20., it is characterized in that described receiver is emitting electrode (12) or the receiver coil (113) with the reception amplifier (23) that is connected the downstream according to each described device in the claim 12 to 19.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102005036354 | 2005-07-29 | ||
| DE102005036354.7 | 2005-07-29 | ||
| DE102005045993.5 | 2005-09-27 | ||
| DE102005063023.5 | 2005-12-14 |
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| CN101233385A true CN101233385A (en) | 2008-07-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2006800278720A Pending CN101233425A (en) | 2005-07-29 | 2006-07-29 | Method For Light Propagation Time Measurement |
| CNA2006800278627A Pending CN101233385A (en) | 2005-07-29 | 2006-07-29 | Method and device for distance measurement by means of capacitive or inductive sensors |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2006800278720A Pending CN101233425A (en) | 2005-07-29 | 2006-07-29 | Method For Light Propagation Time Measurement |
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| Country | Link |
|---|---|
| CN (2) | CN101233425A (en) |
| ES (1) | ES2367143T3 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102292620A (en) * | 2009-01-21 | 2011-12-21 | 格尔德·赖梅 | Method for inductive generating of an electrical measurement signal and related sensor device |
| CN109470130A (en) * | 2018-12-29 | 2019-03-15 | 长沙市开启时代电子有限公司 | It is a kind of to send a reception differential type current vortex displacement detection device |
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| EP2602635B1 (en) * | 2011-12-06 | 2014-02-19 | ELMOS Semiconductor AG | Method for measuring a transfer route by means of compensating amplitude measurement and delta-sigma method and device for performing the method |
| JP6040542B2 (en) * | 2012-03-15 | 2016-12-07 | オムロン株式会社 | Light receiving integrated circuit and photoelectric sensor using the integrated circuit |
| TWI574029B (en) * | 2014-11-21 | 2017-03-11 | 專家科技有限公司 | Ranging method, ranging device, location device and location method |
| EP3423859A1 (en) * | 2016-03-01 | 2019-01-09 | Elmos Semiconductor Aktiengesellschaft | Device for converting a temporal delay of a signal transmitted between a transmitter and a receiver |
| EP3339901B1 (en) * | 2016-12-21 | 2019-04-24 | Hexagon Technology Center GmbH | Laser distance measuring module with adc error compensation by varying sampling times |
| DE102017113237A1 (en) * | 2017-06-16 | 2018-12-20 | Bea Sa | Laser scanner for monitoring a surveillance area |
| EP3654062A1 (en) * | 2018-11-16 | 2020-05-20 | Hexagon Technology Center GmbH | Distance measuring device with high signal dynamics and reference light path adapted thereto |
| CN114637021B (en) * | 2022-05-18 | 2022-08-02 | 四川吉埃智能科技有限公司 | Sub-centimeter-level full-waveform laser radar ranging method and device |
-
2006
- 2006-07-29 CN CNA2006800278720A patent/CN101233425A/en active Pending
- 2006-07-29 ES ES06776514T patent/ES2367143T3/en active Active
- 2006-07-29 CN CNA2006800278627A patent/CN101233385A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102292620A (en) * | 2009-01-21 | 2011-12-21 | 格尔德·赖梅 | Method for inductive generating of an electrical measurement signal and related sensor device |
| CN102292620B (en) * | 2009-01-21 | 2013-12-25 | 格尔德·赖梅 | Method for inductive generating of electrical measurement signal and related sensor device |
| CN103674075A (en) * | 2009-01-21 | 2014-03-26 | 格尔德·赖梅 | Method for inductive generating of electrical measurement signal and related sensor device |
| CN109470130A (en) * | 2018-12-29 | 2019-03-15 | 长沙市开启时代电子有限公司 | It is a kind of to send a reception differential type current vortex displacement detection device |
| CN109470130B (en) * | 2018-12-29 | 2024-02-27 | 湖南开启时代科技股份有限公司 | Transmitting-receiving differential type eddy current displacement detection device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101233425A (en) | 2008-07-30 |
| ES2367143T3 (en) | 2011-10-28 |
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