US-12625132-B2 - Portable blowing type alcohol concentration measuring device and measuring method

US12625132B2US 12625132 B2US12625132 B2US 12625132B2US-12625132-B2

Abstract

A portable blowing alcohol concentration measuring device is provided, including: a housing, a valve body, a first one-way valve, a second one-way valve and a container. The first one-way valve can be opened and closed between the air inlet of the housing and the valve body; a container is provided at the other end of the housing, and the housing and the container are spaced by a PTFE membrane; the second one-way valve has a suction port connected to a drainage port on the container. The opening and closing of the second one-way valve can make the passage between the suction port and the inside of the valve body to achieve a pass-through. By optimizing the structure and testing method, the alcohol in the exhaled gas is fully dissolved in the solution in the container, and the blood alcohol concentration can be obtained by direct measurement using the fitted function.

Inventors

Da BIAN
Yi Chen
Yingji LI
Shanhua QIAN
Zifeng NI
Yongwu Zhao
Xiaohua JIA

Assignees

JIANGNAN UNIVERSITY

Dates

Publication Date: 20260512
Application Date: 20210528
Priority Date: 20210524

Claims (6)

1 . A measurement method using a portable blowing type alcohol concentration measuring device, wherein the portable blowing type alcohol concentration measuring device comprises: a housing ( 4 ); a valve body ( 2 ) and a first one-way valve disposed inside the housing; a second one-way valve disposed on the housing; and a container ( 18 ), configured to hold a liquid, wherein one end of the housing has an air inlet, and the first one-way valve being openable and closeable is disposed between the air inlet and the valve body, the valve body inside has a cross-connected passage leading to the first one-way valve, the second one-way valve and the container, the container is disposed at another end of the housing, and the housing is separated from the container by a PTFE membrane ( 1 ), the container is provided with a drainage port ( 17 ) on a side wall near the end of the housing, the container is provided with an opening, and the opening being sealed by an openable and closeable sealing cap ( 16 ), the second one-way valve is disposed on a side wall of the housing, the second one-way valve has a suction port ( 14 ) connected with the drainage port on the container, and opening and closing of the second one-way valve realize connection and disconnection of the suction port and the passage inside the valve body; wherein the second one-way valve comprises a suction valve body ( 9 ), a suction valve steel ball ( 11 ) and a suction valve spring ( 13 ), wherein the suction valve body has a suction passage through the suction port and the valve body, the suction valve steel ball is movably disposed on the suction passage, so as to realize connection and disconnection between the suction port and the passage inside the valve body, and the suction valve spring is disposed between the suction valve steel ball and a side wall of the housing; wherein the passage inside the valve body comprises a shaped flow passage ( 22 ) penetrating axially along the valve body and a transverse hole ( 23 ) crossed and penetrated with the shaped flow passage, such that during a blowing stage, gas flow through the shaped flow passage induces negative pressure at the transverse hole, resulting in opening of the second one-way valve and allowing water at the suction port to enter the transverse hole through the suction passage; wherein the method comprises: step 1, blowing gas into the air inlet by a human subject, wherein the gas enters solution in the container through the first one-way valve and the valve body; step 2, collecting temperature t, capacitance C and gas pressure value P of the solution in the container; step 3, calculating a capacitance impact factor ΔC based on a temperature change Δt at temperature t relative to a room temperature of 20° C. and a functional relationship equation (5) fitted by the capacitance impact factor ΔC and the temperature change Δt, Δ C=b 0 +b 1 Δt+b 2 Δt 2 +b 3 Δt 3 (5) where b 0 , b 1 , b 2 , and b 3 are fitting coefficients for the function equation; using a calibrated functional relationship equation (3A) of capacitance C and the capacitance impact factor ΔC and alcohol volume percentage d in the solution to calculate the alcohol volume percentage d in the solution, C+ΔC=a 0 +a 1 d′+a 2 d′ 2 +a 3 d′ 3 +a k d′ k (3A) where a 0 , a 1 , a 2 , . . . a k are fitting coefficients and k is a set fitting polynomial order; using gas pressure value P measured by the gas pressure sensor to calculate actual volume V x of the blown-in gas via equation (6): V x = PV 1 P 0 ( 6 ) where V 1 is volume of the gas above the liquid in the container at temperature t, and P 0 is atmospheric pressure; using equation (7) to calculate alcohol volume percentage d 0 in the blown gas, d 0 = d ′ ⁢ V 2 V x ( 7 ) where V 2 is volume of liquid in the container; and step 4, using functional relationship equation (8) of alcohol volume percentage d 0 in the blown gas and alcohol volume percentage V in blood to calculate the alcohol volume percentage V in the blood, V = c 0 + c 1 ⁢ d 0 + c 2 ⁢ d 0 2 + c 3 ⁢ d 0 3 ( 8 ) where c 0 , c 1 , c 2 , and c 3 are fitting coefficients.
2 . The measurement method according to claim 1 , wherein the step of establishing a functional relationship equation of the capacitance C and the alcohol volume percentage d in the solution is: a capacitance calculation equation according to equation (1): C = 2 ⁢ πε 0 ⁢ ε r ⁢ L ln ⁡ ( d 1 / d 2 ) ( 1 ) where ε 0 is dielectric constant in vacuum, ε r is dielectric constant of mixed solution, L is orthogonal length of the two electrodes, d 1 is outer diameter of the capacitor, and d 2 is inner diameter of the capacitor; calculating the dielectric constant ε r of the mixed solution via the measured capacitance C when ε 0 , L, d 1 , and d 2 are given; calculating the alcohol volume percentage d in the solution by equation (2) according to the dielectric constant ε r of the mixed solution, a dielectric constant ε r1 of pure alcohol, and a dielectric constant ε r2 of pure water: √{square root over (ε r )}= d √{square root over (ε r 1 )}+(1− d √{square root over (ε r 2 )} (2) establishing a relationship curve between the capacitance C and the alcohol volume percentage d in the solution based on the n actual measurements of the capacitance C and calculated corresponding alcohol volume percentages d in the solution, and fitting a function C=f(d) of relationship in-between the capacitance C and the alcohol volume percentage d according to equations (3) and (4) using the least squares method: C = f ⁡ ( d ) = a 0 + a 1 ⁢ d + a 2 ⁢ d 2 + a 3 ⁢ d 3 + … ⁢ a k ⁢ d k ( 3 ) Loss = ∑ i = 1 n [ C i - ( a 0 + a 1 ⁢ d i + a 2 ⁢ d i 2 + … ⁢ a k ⁢ d i k ) ] 2 ( 4 ) where Loss is an error sum of squares, the fitting objective of the least squares method is to minimize the error sum of squares, C i is a capacitance of the i th test, d i is a corresponding alcohol volume percentage calculated for the i th test, k≤n, and n is the total number of tests.
3 . The measurement method according to claim 2 , further comprising: calibrating equation (3) using the capacitive impact factor ΔC to yield: C+ΔC=a 0 +a 1 d′+a 2 d′ 2 +a 3 d′ 3 + . . . a k d′ k (3A).
4 . The measurement method according to claim 1 , wherein the first one-way valve comprises an inlet valve spring ( 6 ) and an inlet valve ( 7 ), wherein the inlet valve is movably disposed at an air inlet ( 15 ), and the inlet valve spring is disposed between the inlet valve and the valve body.
5 . The measurement method according to claim 1 , wherein the PTFE membrane allows the passage of gas and prevents the passage of liquid.
6 . The measurement method according to claim 1 , wherein the container is provided with a gas pressure sensor, a capacitance sensor and a temperature sensor, wherein the temperature sensor and the gas pressure sensor are connected to a signal processing unit, and the capacitance sensor is connected to the signal processing unit through an oscillation circuit, an amplification circuit, and an anti-interference circuit.

Description

FIELD OF THE INVENTION The present invention relates to an alcohol concentration measuring device and its measuring method, specifically to a blowing type device for measuring the alcohol volume percentage in a mixed solution of alcohol and water and its measuring method. BACKGROUND OF THE INVENTION At present, it is difficult to directly measure the concentration of alcohol in a mixed solution of alcohol and water, and it is usually done by physical or chemical methods to separate the two, and then calculate and obtain the concentration of alcohol in them. The physical method is mainly based on the difference of boiling point of the two liquids to separate them by distillation, and then calculate the concentration of alcohol in them, while the chemical method is more difficult. These indirect measurement methods are not only time consuming, but also not very accurate and costly to test, and they cannot meet the requirements of use for measurements with high accuracy. Therefore, it has a very important meaning for finding a more efficient, more accurate and less cost method to test the alcohol volume percentage in blood. The conventional blood alcohol concentration measuring devices need to collect blood and are usually operated by hospital medical personnel, which are not suitable for general operators to operate portably, while other blowing type alcohol concentration measuring methods are subject to environmental and other factors that reduce the accuracy of measuring compared with blood measuring methods. SUMMARY OF THE INVENTION The purpose of the present invention is to provide a portable blowing type measuring device and measuring method for directly measuring the alcohol concentration in a mixed solution of alcohol and water or other liquids with good portability, low cost, and improved accuracy of blowing type alcohol measurement, so as to overcome the defects of the prior art. The present invention uses the following technical solutions to achieve the above purpose. In an embodiment, a portable blowing type alcohol concentration measuring device is provided, and the device comprises: a housing (4); a valve body (2) and a first one-way valve disposed inside the housing; a second one-way valve disposed on the housing; and a container (18), configured to hold a liquid, wherein one end of the housing has an air inlet, and the first one-way valve being openable and closeable is disposed between the air inlet and the valve body, the valve body inside has a cross-connected passage leading to the first one-way valve, the second one-way valve and the container, the container is disposed at another end of the housing, and the housing is separated from the container by a PTFE membrane (1), the container is provided with a drainage port (17) on a side wall near the end of the housing, the container is provided with an opening, and the opening being sealed by an openable and closeable sealing cap (16), the second one-way valve is disposed on a side wall of the housing, the second one-way valve has a suction port (14) connected with the drainage port on the container, and opening and closing of the second one-way valve realize connection and disconnection of the suction port and the passage inside the valve body. In the embodiment, the first one-way valve comprises an inlet valve spring (6) and an inlet valve (7), wherein the inlet valve is movably disposed at an air inlet (15), and the inlet valve spring is disposed between the inlet valve and the valve body. In the embodiment, the second one-way valve comprises a suction valve body (9), a suction valve steel ball (11) and a suction valve spring (13), wherein the suction valve body has a suction passage through the suction port and the valve body, the suction valve steel ball is movably disposed on the suction passage, so as to realize connection and disconnection between the suction port and the passage inside the valve body, and the suction valve spring is disposed between the suction valve steel ball and a side wall of the housing. In the embodiment, the passage inside the valve body comprises a shaped flow passage (22) penetrating axially along the valve body and a transverse hole (23) crossed and penetrated with the shaped flow passage. In the embodiment, the PTFE membrane allows the passage of gas and prevents the passage of liquid. In the embodiment, the container is provided with a gas pressure sensor, a capacitance sensor and a temperature sensor, wherein the temperature sensor and the gas pressure sensor are connected to a signal processing unit, and the capacitance sensor is connected to the signal processing unit through an oscillation circuit, an amplification circuit, and an anti-interference circuit. In a further embodiment, a measurement method based on the portable blowing type alcohol concentration measuring device is provided, and the method includes steps: step 1, blowing gas into the air inlet by tester, and the gas enters solution in the