CN100432704C - Multi-parameter detecting method and apparatus for liquid drop - Google Patents

Abstract

The present invention relates to a method and a device of the multi-parameter detection for liquid drop. The method of the present invention comprises the following steps that the liquid drop falling vertically passes a first position sensor, a capacitance sensor, a converter and a second position sensor in sequence in the process of falling vertically; subsequently, the integrated computation for an output value Sc from the capacitance sensor and the converter is carried out by a signal processing unit; the speed value of the corresponding liquid drop passing the first position sensor and the break point position value of the corresponding liquid drop to be dropped are figured out by the installation distance L and the data T between the first position sensor and the second position sensor. The present invention can directly carry out the real-time multi-parameter detection for the volume of each falling liquid drop, and moreover, the present invention has the advantages of high detection precision and dynamic detection speed. Furthermore, the present invention can be applied to the liquid drop analysis and can realize the purpose of manufacturing a rainfall detection analytical instrument.

Description

The multi-parameter detecting method of drop and device

Technical field

The present invention relates to a kind of multi-parameter detecting method and device of drop.

Background technology

Existing drop detection method mainly is that droplet size is measured, as rain gage.The anti-rain gage that struggles against of mechanical type is arranged, and its adopts the metering to drop batch box mechanical reverse number of times, therefore has shortcomings such as mechanism's complexity, instrument be huge; Also have siphon rainfall recorder, its adopts the metering system that drop accumulation liquid surface float is changed and discharges liquid level by siphon and recovers to measure zero point, therefore exists poor repeatability at zero point, shortcoming that measuring accuracy is low; Photo-electric drop meter is arranged again, and it is with the method for position switch to the numeration of drop number, therefore exists the drop size variation will influence the problem of measuring accuracy.Existing drop detection method all generally can only detect the volumetric parameter of drop, and precision and reliability are not high.

Summary of the invention

The object of the present invention is to provide a kind of multi-parameter detecting method and device of drop, can detect the volume of each drop, parameters such as breakpoint location when drop is ready-made, and accuracy of detection high measurement speed is fast.

For achieving the above object, the present invention adopts following technical proposals:

A kind of multi-parameter detecting method of drop comprises the vertical drop drop, it is characterized in that the drop vertical drop passes through primary importance sensor, capacitance sensing and converter and second place sensor successively, and drop is at T ₀During constantly through the primary importance sensor, the primary importance sensor sends signal T ₀To signal processing unit, begin the output valve Sc of capacitance sensing and converter is carried out integral and calculating by signal processing unit, drop is at T ₁During constantly through second place sensor, second place sensor sends signal T ₁To signal processing unit, signal processing unit draws the mistiming T=T of two signals ₁-T ₀, and finish integral and calculating, draw the first integral value and promptly be drop through under the state to the integrated value of capacitance sensing and converter output valve Sc ${\mathrm{\Σ}}_1=\underset{T_0}{\overset{T_1}{\∫}}{S}_c\mathrm{dt};$ Under back to back dripless state, signal processing unit is from T ₂Time begins the output valve Sc of capacitance sensing and converter is carried out integral and calculating again, at T ₃Time finishes integral and calculating, draws the second integral value and promptly be the integrated value of capacitance sensing and converter output valve under the dripless state ${\mathrm{\Σ}}_2=\underset{T_2}{\overset{T_3}{\∫}}{S}_c\mathrm{dt};$ At last, signal processing unit calculates second integral value and first integral value relative changing value under the ratio when waiting $\mathrm{\Δ\Σ}=({\mathrm{\Σ}}_2-\frac{T_3-T_2}{T_1-T_0}\·{\mathrm{\Σ}}_1)/{\mathrm{\Σ}}_2,$ Draw the bulking value Q=F (Δ ∑) of corresponding drop by relative changing value's Δ ∑, again by the mounting distance L and the data T of first position transducer and second position transducer, the velocity amplitude when calculating corresponding drop through first position transducer $V\left(T_0\right)=\frac{2L-g{T}^2}{2T}$ Breakpoint location value when forming with corresponding drop $H=\frac{{\left[V\left(T_0\right)\right]}^2}{2g}.$

Said method is as follows to the testing step of each drop:

A. the drop vertical drop is at T ₀During constantly through the primary importance sensor, primary importance sensor signalling T ₀Pick up counting for signal processing unit, signal processing unit inside and to the output valve S of capacitance sensing and converter _cCarry out integral and calculating;

B. work as droplets fall at T ₁During constantly through second place sensor, second place sensor signalling T ₁Give signal processing unit, signal processing unit finishes integral and calculating, and draws signal T ₁With signal T ₀Mistiming T and first integral value ∑ ₁, T and ∑ ₁Respectively be taken as:

T＝T ₁-T ₀，

${\mathrm{\Σ}}_1=\underset{T_0}{\overset{T_1}{\∫}}{S}_c\mathrm{dt}$

C. at back to back dripless state, signal processing unit is from T ₂Time begins the output valve S to capacitance sensing and converter (4) again _cCarry out integral and calculating, at T ₃The time signal processing unit finishes integral and calculating, draws second integral value ∑ ₂, ∑ ₂Be taken as:

${\mathrm{\Σ}}_2=\underset{T_2}{\overset{T_3}{\∫}}{S}_c\mathrm{dt}$

D. signal processing unit (6) calculates second integral value and the relative changing value Δ ∑ of first integral value under equal time, and the Δ ∑ is taken as:

$\mathrm{\Δ\Σ}=({\mathrm{\Σ}}_2-\frac{T_3-T_2}{T_1-T_0}\·{\mathrm{\Σ}}_1)/{\mathrm{\Σ}}_2$

And then calculate the bulking value Q of corresponding drop, Q is taken as:

Q＝F(Δ∑)

F in the formula (Δ ∑) is a monotonic quantity of data fitting by experiment.

E. signal processing unit is according to the mounting distance L of physics falling bodies formula, data T, two position transducers, the velocity amplitude V (T when calculating drop through first position transducer respectively ₀) and the breakpoint location value H of corresponding drop when forming, V (T ₀) and H respectively be taken as:

V(T ₀)＝(2L-gT ²)/(2T)，

H＝[V(T ₀)] ²/(2g)

Wherein g is the acceleration of gravity coefficient;

A kind of device that is used for above-mentioned drop detection method, comprise a signal processing unit, it is characterized in that having and be suitable for the drop vertical drop and pass through vertically superposed primary importance sensor, capacitance sensing and converter and second place sensor successively, the output of two position transducers inserts signal processing unit, and the output of capacitance sensing and converter is connected to signal processing unit.

The present invention compared with prior art, have following conspicuous outstanding feature and remarkable advantage: the present invention adopts and at capacitance sensing and converter two position transducers is installed up and down, and the one, determine beginning and ending time and mistiming thereof the T of drop through capacitance sensing and converter; The 2nd, adopt to have under drop process and two states of dripless the output valve of capacitance sensing and converter is carried out integration twice, and calculate the relative changing value of integrated value under the equal time ratio twice, draw the bulking value of corresponding drop with this relative changing value, eliminated the background drift that small-signal detects like this, it is accurate and reliable to have guaranteed that droplet size detects; The 3rd, the breakpoint location value when velocity amplitude when utilizing mistiming T to draw drop process primary importance sensor and corresponding drop are ready-made.The present invention directly carries out real-time multiparameter to each dripping drops volume to detect, the accuracy of detection height, and it is fast to detect dynamic speed.Drop multiparameter of the present invention detects the flow measurement and the surface tension analysis that can realize drop, can be applicable to liquid drop analysis and realizes rainfall check and analysis instrument.

Description of drawings

Fig. 1 is the structural principle block diagram of one embodiment of the invention.

Embodiment

A preferred embodiment of the present invention such as following: referring to Fig. 1, to as the ready-made vertical drop drop 2 of aperture funnel 1, this method is as follows to the testing step of each drop 2:

A. drop 2 vertical drops are at T ₀During constantly through primary importance photoelectric sensor 3, primary importance photoelectric sensor 3 signalling T ₀Pick up counting for signal processing unit 6, signal processing unit 6 inside and to the output valve S of capacitance sensing and converter 4 _cCarry out integral and calculating;

B. work as drop and drop on T 2 times ₁During constantly through second place photoelectric sensor 5, second place photoelectric sensor 5 signalling T ₁Give signal processing unit 6, signal processing unit 6 finishes integral and calculating, and draws signal T ₀With signal T ₁Mistiming T and first integral value ∑ ₁, T and ∑ ₁Respectively be taken as:

T＝T ₁-T ₀，

${\mathrm{\Σ}}_1=\underset{T_0}{\overset{T_1}{\∫}}{S}_c\mathrm{dt}$

C. at back to back dripless state, signal processing unit 6 is from T ₂Time begins the output valve S to capacitance sensing and converter 4 again _cCarry out integral and calculating, at T ₃Time signal processing unit 6 finishes integral and calculating, draws second integral value ∑ ₂, ∑ ₂Be taken as:

${\mathrm{\Σ}}_2=\underset{T_2}{\overset{T_3}{\∫}}{S}_c\mathrm{dt}$

D. signal processing unit 6 calculates second integral value and the relative changing value Δ ∑ of first integral value under equal time, and the Δ ∑ can be taken as:

$\mathrm{\Δ\Σ}=({\mathrm{\Σ}}_2-\frac{T_3-T_2}{T_1-T_0}\·{\mathrm{\Σ}}_1)/{\mathrm{\Σ}}_2$

And then calculate the bulking value Q of corresponding drop, Q is taken as:

Q＝F(Δ∑)

F in the formula (Δ ∑) is a monotonic quantity of data fitting by experiment.

E. signal processing unit 6 is according to the mounting distance L of physics falling bodies formula, data T, two position transducers 3 and 5, the velocity amplitude V (T when calculating drop through first position transducer 3 respectively ₀) and the breakpoint location value H of corresponding drop when forming, V (T ₀) and H respectively be taken as:

V(T ₀)＝(2L-gT ²)/(2T)，

H＝[V(T ₀)] ²/(2g)

Wherein g is the acceleration of gravity coefficient;

The device that is used for the multi-parameter detecting method of this drop is: a processing unit is arranged, and have and be suitable for drop 2 vertical drops and pass through vertically superposed primary importance photoelectric sensor 3, capacitance sensing and converter 4 and second place photoelectric sensor 5 successively, two photoelectric sensor for position 3 and 5 output insert signal processing unit 6, and the output of capacitance sensing and converter 4 is connected to signal processing unit 6.

Claims (2)

1. the multi-parameter detecting method of a drop, comprise vertical drop drop (2), it is characterized in that drop (2) vertical drop passes through primary importance sensor (3), capacitance sensing and converter (4) and second place sensor (5) successively, during drop (2) process primary importance sensor (3), primary importance sensor (3) sends signal T ₀To signal processing unit (6), begin the output valve Sc of capacitance sensing and converter (4) is carried out integral and calculating by signal processing unit (6), during drop (2) process second place sensor (5), second place sensor (5) sends signal T ₁To signal processing unit (6), signal processing unit (6) draws the mistiming T=T of two signals ₁-T ₀, and finish integral and calculating, draw the first integral value and promptly be drop through under the state to the integrated value of capacitance sensing and converter (4) output valve Sc ${\mathrm{\Σ}}_1=\underset{T_0}{\overset{T_1}{\∫}}{S}_c\mathrm{dt};$ Under back to back dripless state, signal processing unit (6) is from T ₂Time begins the output valve Sc of capacitance sensing and converter (4) is carried out integral and calculating again, at T ₃Time finishes integral and calculating, draws the second integral value and promptly be the integrated value of capacitance sensing and converter (4) output valve Sc under the dripless state ${\mathrm{\Σ}}_2=\underset{T_2}{\overset{T_3}{\∫}}{S}_c\mathrm{dt};$ At last, signal processing unit (6) calculates second integral value and the relative changing value of first integral value under the equal time ratio $\mathrm{\Δ\Σ}=({\mathrm{\Σ}}_2-\frac{T_3-T_2}{T_1-T_0}\·{\mathrm{\Σ}}_1)/{\mathrm{\Σ}}_2,$ Draw the bulking value Q=F (Δ ∑) of corresponding drop by relative changing value's Δ ∑, F in the formula (Δ ∑) is a monotonic quantity of data fitting by experiment; Again by mounting distance L and the data T of first position transducer (3) with second position transducer (5), the velocity amplitude when calculating corresponding drop first position transducer of process (3) $V\left(T_0\right)=\frac{2L-{\mathrm{gT}}^2}{2T}$ Breakpoint location value when forming with corresponding drop $H=\frac{{\left[V\left(T_0\right)\right]}^2}{2g},$ G is the gravity acceleration factor in the formula.

2. device that is used for the multi-parameter detecting method of the described drop of claim 1, comprise a signal processing unit (6), it is characterized in that having and be suitable for drop (2) vertical drop and pass through vertically superposed primary importance sensor (3), capacitance sensing and converter (4) and second place sensor (5) successively, the output of two position transducers (3,5) inserts signal processing unit (6), and the output of capacitance sensing and converter (4) is connected to signal processing unit (6).