CN110243453B - Method for detecting water inlet noise of toilet water tank by A weighting sound power level measurement method - Google Patents

Abstract

The invention relates to a method for detecting water inlet noise of a water inlet valve of a toilet water tank, which comprises the following steps: installing and debugging a sample; determining a sound source reference body and a measuring surface; sound pressure level measurement; calculating sound power level and correcting background noise, test environment and meteorological conditions; evaluating the result; it is characterized in that: slow time weighting characteristic "S" of A-weighted equivalent sound level using a sound level meter for measuring the sound level on a parallelepiped measuring surface in cumulative percentage sound power level L_WA(50)Accurately and quantitatively detecting the water inlet noise of the characterized water inlet valve; the invention provides for a weight cumulative percentage time average sound pressure level L 'of water ingress noise and background noise on a parallelepiped measuring surface'_pAi(ST)(50)And L_pAi(B)(50)Measuring to calculate the sound power level L in a specific water replenishing period_WA(50)And provides the basis for evaluating the results. The invention fills the blank in the technical field of the detection of the water inlet noise of the water inlet valve of the toilet water tank, and can provide a detection technical support for improving the product quality and standardizing the market order.

Description

Method for detecting water inlet noise of toilet water tank by A weighting sound power level measurement method

Technical Field

The invention relates to a noise quantitative test method, in particular to a method for measuring the sound power level L on the surface of a parallelepiped by using the slow time weighting characteristic S of the equivalent sound level weighted by a sound level meter A to accumulate the percentage sound power level L_WA(50)A method for detecting water inlet noise of a water inlet valve of a toilet water tank belongs to the technical field of physical and chemical performance detection of toilet water tank accessories.

Background

In recent years, toilets serve as basic civilian problems and important civilized windows, the construction quality of the toilets cannot be ignored, and along with the increasing of the use amount of the toilet and water tank accessories in important civilian fields such as catering, traveling, home and the like and the enhancement of people health and environmental awareness, the monitoring and control of the water inlet noise of the toilet water tank are increasingly concerned by various social circles.

The water inlet valve is used as a core part of a toilet cistern accessory, and the water inlet noise of the water inlet valve accounts for a higher weight in the toilet flushing noise, and directly influences and determines the magnitude level of the flushing noise. The noise generated in the toilet flushing process belongs to the category of hydrodynamic noise and is mainly composed of structural vibration noise of a pipeline, fluid noise of water and cavitation noise; the fluid noise is an important source of flushing noise and mainly comprises noise of water flowing in a water ring and on the inner wall of the toilet bowl, noise of water rotating in the toilet bowl and noise of broken siphons and water replenishing of a water inlet valve in the later stage of pollution discharge; therefore, the flushing noise is not only closely related to the internal structure of the toilet bowl, but also largely influenced by the water inlet noise of the water inlet valve of the toilet tank.

Because the noise has all characteristics of sound wave transmission, the sound intensity is gradually weakened along with the increase of the transmission distance, and the sound waves are reflected, diffracted, scattered, absorbed and the like when encountering obstacles; the propagation characteristic closely related to the water inlet noise test of the water inlet valve is the directivity of sound waves, namely, at the position with the same distance with a sound source, the sound intensity received in different directions has certain energy difference due to the fact that the noise source has the bright directivity. Experiments show that in the water inlet process of the water inlet valve, the sound intensity above the water tank is maximum, the front noise intensity is second, the left noise intensity and the right noise intensity are weak, and the rear noise intensity is minimum; therefore, the directivity of the noise source is used to reasonably set the distribution of the measuring points during the actual measurement.

In recent years, due to law enforcement requirements of environmental protection departments, although the noise detection standard system in China is developed greatly, the field related to the existing professional noise test specification is only limited to indoor and outdoor environments, vehicles, equipment, electric appliances and the like, and the field of water inlet noise measurement of a water inlet valve is not related. In order to strictly control the quality of the water tank fittings, 2011 national distribution enforces the mandatory standard GB 26730-. However, the technical requirements of the method for detecting the water inlet noise of the water inlet valve in the standard 7.5-item noise test are extremely simple, and the water inlet valve is arranged on a standard water tank with the height of 400mm from the ground without adding a water tank cover in a test chamber with the environmental noise of not higher than 30dB (A); a sound level meter with the precision of not less than 0.1d B (A) is arranged, and a detection head of the sound level meter is 1m away from the front surface of the water tank and is 1m higher than the ground; adjusting the inlet water dynamic pressure to 0.3MPa, opening the inlet valve, measuring after 10s, recording the highest noise value of the whole inlet water process, repeating for three times, and reporting the arithmetic average value. The acoustic principle of a sound source reference body, a measurement surface and the like is not involved, and key technical contents of a corresponding result calculation formula, data reduction, measurement uncertainty and the like are also lacked; the detection operation of the water inlet noise of the water inlet valve is lack of scientificity and normalization, and the result data is not comparable and repeatable and is difficult to play a role in guiding and supporting the improvement of product quality and the specification of market order. After extensive investigation on domestic main production places such as Hebei, Guangdong and Henan, accurate and quantitative verification on the product quality is difficult to carry out due to the loss of related testing technologies. The shortage of the detection method influences the popularization of enterprises to new technologies to a certain extent, troubles the trust of consumers to products and restricts the further development of the industry.

At present, sanitary products are listed in the key field of quality improvement, the standard system of detection methods of sanitary ceramics and matched products thereof is perfected, and the research and development of a water inlet noise detection technology of a water inlet valve of a toilet water tank are trending. Therefore, in order to promote the quality of related products to be improved and to fill up the short toilet boards which affect the quality of life of the masses, the supporting function of the patent technology on the standard research needs to be strengthened; the invention has a certain practical significance for helping the industry transformation and upgrade of toilet water tank accessories in China.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a method for measuring the sound power level on the surface of a parallelepiped by accumulating the percentage sound power level by using the slow time weighting characteristic S of the equivalent sound level of a sound level meter AL_WA(50)The method for detecting the water inlet noise of the water inlet valve of the toilet water tank can solve the problem of accurate and quantitative measurement of water inlet/drainage noise of bathroom ceramics such as water inlet noise of the water inlet valve and flushing noise of a toilet.

In order to solve the technical problems, the invention adopts the technical scheme that:

a method for detecting the water inlet noise of a water inlet valve of a toilet cistern comprises the following steps: (1) installing and debugging a sample; (2) determining a sound source reference body and a parallelepiped measuring surface; (3) sound pressure level measurement; (4) calculating sound power level and correcting background noise, test environment and meteorological conditions; (5) evaluating the detection result; it is characterized by that it uses sound level meter A to weight the slow time weighting characteristic "S" of equivalent sound level to make the cumulative percentage sound power level L on the parallelepiped measuring surface_WA(50)Accurate quantitative determination is carried out to the noise of intaking of stool pot water tank water intaking valve of sign, and is specific:

in sound pressure level measurement:

(1) before measuring the water inlet noise of a toilet water tank inlet valve in a semi-anechoic chamber or a reverberation chamber, according to the relevant regulations in GB/T3767-2016 engineering method for measuring the sound power level of a noise source and the approximate free field above an acoustic energy level reflecting surface by an acoustic sound pressure method, aiming at the typical installation requirements of various toilet water tank inlet valve samples, the positioning of sound source reference bodies under different reflecting plane conditions is determined and the characteristic dimension d of the sound source is calculated₀(ii) a Simultaneously selecting a parallelepiped measuring surface corresponding to the water inlet noise source reference body of the water inlet valve, determining the size of the parallelepiped measuring surface, and determining the coordinates of microphone position arrays on different measuring surfaces;

(2) in a semi-anechoic chamber or a reverberation chamber, taking a specific water replenishing period of a water inlet valve of a toilet water tank as integral time of audio signal acquisition, and determining the accumulated percentage time average sound pressure level L of background noise on the measurement surface of a selected parallel hexahedron by using a slow time weighting characteristic S of weighting equivalent sound level by A of a sound level meter_pAi(B)(50)(ii) a Then starting a water replenishing device of a water inlet valve under the test dynamic pressure condition of 0.30MPa +/-0.05 MPa; aiming at different water supplement quantity (half-flushing or full-flushing) test requirements of a toilet water tank, the method is specially usedIn the water replenishing period, the accumulated percentage time average sound pressure level L 'of the water inlet noise of the water inlet valve on the selected parallelepiped measuring surface is measured by using the slow time weighting characteristic S of the weighting equivalent sound level A of the sound level meter'_pAi(ST)(50)；

In the acoustic power level calculation:

according to the related concepts and calculation formulas in GB/T3767-2016, under the test dynamic pressure condition of 0.30MPa +/-0.05 MPa, taking a specific water replenishing period of a water inlet valve of a toilet water tank as the integration time of audio signal acquisition, and integrating the A weight accumulated percentage time average sound pressure level L 'of the water inlet noise and the background noise measured by a sound level meter on the selected parallelepiped measuring surface'_pAi(ST)(50)And L_pAi(B)(50)As the basic data, calculating the corresponding time-averaged sound pressure level mean value

And

and correcting value K for background noise_1ATesting environment correction value K_2AAnd a weather condition correction value C₁、C₂Analyzing the influence of the water inlet noise, and deducing the A-weighted cumulative percentage acoustic power level L of the water inlet noise of each toilet cistern inlet valve sample under the condition of the set dynamic pressure_WA(50)And the average value of the water inlet noise A weight cumulative percentage acoustic power level of each group of samples

Simultaneously, defining corresponding data reduction requirements and measurement uncertainty ranges;

in the evaluation of the results:

when a certain sample water inlet noise A is weighted, the cumulative percentage sound power level L is calculated_WA(50)The water inflow noise A of 3 samples in the group is weighted and accumulated in percentage acoustic power level L_WA(50)Arithmetic mean value

10%, a group of samples needs to be re-extractedRepeating the experiment; and calculating the accumulated percentile acoustic power level L of the water inlet noise measured by a parallelepiped measuring surface method by using the slow time weighting characteristic S of the A weighting equivalent sound level of the sound level meter under the condition of the set dynamic pressure of the front and the back groups of water inlet valve samples of the toilet water tank_WA(50)Is arithmetic mean of

If a certain sample water inlet noise A is weighted and accumulated the percentage acoustic power level L_WA(50)The water inlet noise A of more than the two groups of 6 samples is counted and accumulated the percentage sound power level L_WA(50)Arithmetic mean value

10% of the total weight is discarded; the accumulated percentage acoustic power level L is calculated by weighting the water inlet noise A of the rest water inlet valve sample_WA(50)Is arithmetic mean of

The water inlet noise is used as the evaluation index of the water inlet noise of the water inlet valve sample of the toilet water tank.

Compared with the prior art, the invention adopting the technical scheme has the beneficial effects that:

(1) the advancement is as follows: in the acoustic environment of a semi-anechoic chamber or a reverberation chamber, background noise and water inlet noise on the surface of a parallelepiped measurement are measured by applying a slow time weighting characteristic S of an A weighting equivalent sound level of a modern precision instrument-a sound level meter, and an A weighting cumulative percentage sound power level L capable of correctly reflecting the influence of the A weighting equivalent sound level on human psychology and physiology is adopted in view of the fact that a water inlet valve water filling mode is started to be a transient process_WA(50)As subjective evaluation parameters; the detection technology has certain advancement, achieves the modernization of the water inlet noise detection of the water inlet valve of the toilet water tank, and lays a necessary hardware foundation for realizing the precision of the detection result.

(2) Scientifically: on the basis of following the acoustic general guide rule in GB/T3767-2016, a parallelepiped measurement surface acoustic model is established according to an envelope sound source test principle aiming at a water inlet noise generation mechanism and a propagation path of a water inlet valve based on the non-continuous characteristic of noise caused by liquid unstable state flow; the influence of factors such as background noise, environment and meteorological conditions on the detection result is comprehensively analyzed, the measurement result under the working pressure test condition of the water supply pipeline of the civil building is used as the water inlet noise evaluation index, the actual use state of toilet water tank accessories and the attention focus of consumers are met, and the scientificity of the detection method is improved.

(3) Standardization: evaluating the test result according to the national environmental protection requirement and the product quality standard, and referring to the corresponding regulations in the national acoustic basic standard GB/T3767-; and the structure diagrams of the applicable reference body and the measuring surface of the parallelepiped are provided, a series of key technical contents such as sample installation, measuring point coordinates, measuring steps, a calculation formula, uncertainty, result evaluation and the like are determined, and the quantification of the inlet noise detection result of the inlet valve of the toilet water tank can be realized.

(4) Prospective: at present, the detection technology related to the water inlet noise of the water inlet valve at home and abroad is relatively simple, the relevant acoustic principle foundation is lacked, and the applicability and the accuracy of the test method are poor; the method is applicable to a measuring surface according to related acoustic guiding rules and related A weighting sound power level measuring principles in GB/T3767-2016 (engineering method for measuring approximate free field above sound power level and sound energy level reflecting surface by acoustic sound pressure method) of ISO 3744:2010, a calculation formula is scientific, the accuracy level of a measuring result is 2 levels, and the method has certain prospect technically.

(5) The accuracy is as follows: a sound level meter with high automation degree and advanced and mature technology is used as test equipment, and the evaluation results of three toilet cistern inlet valve samples are used as final judgment conclusions; selecting slow time weighting characteristic S of A weighting equivalent sound level of an applied sound level meter in a specific water replenishing period, and measuring the accumulated percentage sound power level L of the water inlet noise by a parallelepiped measuring surface method_WA(50)As a correlation result evaluation index; and correcting the influence factors such as background noise, test environment, meteorological conditions and the like to comprehensively judge the measurement processAnd the measurement error can be effectively avoided due to the accumulation effect of medium uncertainty.

(6) The innovation is as follows: aiming at the influence of water supply pressure on the water inlet noise of a water inlet valve of a toilet water tank, the noise test requirements are met according to the general pressure range of a water supply pipeline of a civil building and under different water supplement quantity conditions; selecting A weight cumulative percentage acoustic power level L of water inlet noise on a parallelepiped measuring surface in a specific water replenishing period (half-stroke or full-stroke)_WA(50)As a result evaluation index for each inlet valve sample; the installation conditions of the test water tank and the technical requirements of water tank accessories are determined, the accuracy and the representativeness of the detection result are improved by limiting the measurement frequency and the data processing of the background noise and the water inlet noise at the coordinates of each measurement point, and the blank of the current related test technical field can be filled.

(7) Operability: the sound level price is cheap, the application is extensive, the sample installation, debugging and a series of experimental operations stipulated by the method of the invention are simple and easy to do; the method has the advantages that technical contents related to test parameters, measurement surfaces, measuring point arrays, test steps, calculation formulas, data processing, evaluation standards and the like are clearly and specifically described, related diagram illustrations are visual and accurate, and the method is easy to understand and master, so that the method has strong operability in the patent implementation process, and is beneficial to promoting transfer and transformation of achievements and popularization and application.

(8) Universality: based on the advantages, the method has stronger practicability and is favorable for expanding the popularization and application in inspection, study, research and production fields; the device is beneficial to realizing universality of a detection technology for supporting the water inlet noise of a water tank water inlet valve of a toilet, and can provide reference for the washing noise of ceramic toilets, squatting pans and urinals, the noise generated by products such as other sanitary ceramic products such as wash basins, bidets and the like and the noise generated by products such as water supply pipelines and drainage pipelines and the like in the using process and the detection technology research thereof.

Further, the preferred scheme of the invention is as follows:

the sample installation and debugging are carried out according to the following steps:

(1) taking 3 water inlet valve samples of toilet tank fittings of the same type, specification and size produced by the same manufacturer and the same batch as a group, wherein the use mode can be side pressing or top pressing (single-flushing type or double-flushing type);

(2) the standard water tank meeting the technical requirements of national standard GB 26730-: 400mm × 175mm × 300 mm; the relative water level of each component of a standard water tank or a flushing water tank (not comprising a hidden water tank) after being installed meets the requirement of item 5.4.1, and the relative water level of each component of the hidden water tank after being installed meets the requirement of item 5.4.10.2;

(3) installing a water inlet valve sample inside a test water tank according to the use instruction of a production plant, and for a water inlet valve provided with a water supplementing device, firmly fixing a water supplementing pipe on the water inlet valve and marking a rated water supplementing ratio, wherein the water supplementing quantity can meet the water seal recovery requirement of a toilet; according to the regulations of 5.2.3, 5.2.4 and 5.2.8 in GB 26730-; after static pressure and dynamic pressure tightness tests, the rising degree of the water level of the water tank is not more than 8mm, and no visible drip leakage exists after the water inlet valve is closed; when the water is drained to a specified height, the water inlet valve can be automatically opened, the water can be automatically closed after the water is fed to a working water level, and the height difference of the working water level of the water fed for 5 times is not more than 5 mm;

(4) when the toilet bowl matched with the water tank provided with the water inlet valve sample to be tested is not installed close to any wall, if the test is carried out in the acoustic environment similar to the free field above the reflecting surface of the semi-anechoic chamber, the test water tank can be directly placed in the center of the ground through the supporting frame without adding a water tank cover; the height of the bottom of the water tank from the indoor ground is 450mm, and the normal flushing function is ensured. If the test is carried out in a rigid wall test chamber or a special reverberation chamber, the test water tank can be placed on the ground through the supporting rack without adding a water tank cover; the height from the bottom of the water tank to the indoor ground is 450mm, and the distance between the water tank and any wall in the room is not less than 1.0 m; meanwhile, the normal flushing function is ensured;

(5) when the toilet bowl matched with the water tank provided with the water inlet valve sample to be tested is installed close to a wall, the test can be carried out in a rigid wall surface test chamber or a special reverberation chamber, the test water tank is directly placed on the ground through the supporting rack, and a water tank cover is not added; the height from the bottom of the water tank to the indoor ground is 450mm, the distance between the back of the water tank and the wall against which the water tank leans is 15cm +/-5 cm, and the distance between the water tank and the other three indoor walls is not less than 1.5 m; meanwhile, the normal flushing function is ensured;

(6) when the pedestal pan matched with the water tank provided with the water inlet valve sample to be tested is installed by a corner, the pedestal pan can be tested in a rigid wall test chamber or a special reverberation chamber, the test water tank is directly placed on the ground through the support frame, and a water tank cover is not added; the height of the bottom of the water tank from the indoor ground is 450mm, and the back and the side of the water tank are 33

The distance between the walls is 15cm +/-5 cm, and the distance between the walls and the other two indoor walls is not less than 1.5 m; while ensuring proper flushing function.

The determination of the sound source reference body and the parallelepiped measuring surface is carried out according to the following steps:

(1) determination of the shape and the size of the water inlet noise source reference body of the water inlet valve: setting the position and the size of a sound source reference body by using a three-dimensional coordinate system according to the relevant regulations of item 7.1 in GB/T3767-2016 engineering method for measuring sound power level and approximate free field above a sound energy level reflecting surface by an acoustic pressure method; aiming at different installation modes of a ceramic toilet bowl matched with a water tank for assembling a sample of the water inlet valve to be detected, the center of a tank body formed by a sound source reference body and mirror images of the sound source reference body on adjacent reflection planes is used as a coordinate origin O, and a horizontal axis x and a horizontal axis y are respectively parallel to the length and the width of the reference body. Length l of sound source reference body using horizontal width of test water tank₁And the width l taking the horizontal length of the test water tank as the sound source reference body₂And the height l taking the vertical distance from the working water level line of the test water tank to the ground as a sound source reference body₃. Characteristic dimension d of sound source reference body corresponding to different test environment conditions₀Are respectively [ (l)₁/2)²+(l₂/2)²+l₃ ²]^1/2(a reflection plane), [ l [ ]₁ ²+(l₂/2)²+l₃ ²]^1/2(two reflection planes) and [ l₁ ²+l₂ ²+l₃ ²]^1/2(three reflection planes) in meters (m);

(2) determination of the parallelepiped measuring surface and its microphone position array: according to the relevant regulations of 7.2.4 th and 8.1.2 th items in the standard GB/T3767-2016, a parallelepiped measuring surface adopted in the test and a sound source reference body have the same-oriented coordinate origin and appearance shape, namely an imaginary parallelepiped with the area of S, enveloping the water inlet noise source of the water inlet valve to be tested, and the distance between each side of the imaginary parallelepiped measuring surface and the reference body of d, wherein d is more than or equal to 1.0 m.

If the toilet bowl matched with the water tank provided with the water inlet valve sample to be measured is not close to any wall when being installed, the position array coordinates of the microphone on the parallelepiped measuring surface are shown in table 1, and the area S is calculated according to the formula (1):

S＝4(ab+bc+ca)...............................................(1)

in the formula: a is 0.5l₁+d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively the length, width and height of the sound source reference body; the measurement distance d is 1.0 m.

TABLE 1 parallelepiped measuring surface microphone position array coordinates with water inlet valve samples on one reflection plane

Microphone location

1

2

3

4

5

6

7

8

9

x

a

0

－a

0

a

－a

－a

a

0

y

0

b

0

－b

b

b

－b

－b

0

z

0.5c

0.5c

0.5c

0.5c

c

c

c

c

c

If the toilet bowl matched with the water tank provided with the water inlet valve sample to be measured is installed close to the wall, the position array coordinate of the microphone on the measuring surface of the parallelepiped is shown in table 2, and the area S is calculated according to the formula (2):

S＝2(2ab+bc+2ca)..............................................(2)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively, the length (distance from the wall to the front end face), width and height of the sound source reference body; the measurement distance d is 1.0 m.

TABLE 2 parallelepiped Measure surface microphone position array coordinates with intake valve samples on two reflection planes

Microphone location

1

2

3

4

5

6

x

2a

a

a

2a

2a

a

y

0

b

－b

b

-b

0

z

0.5c

0.5c

0.5c

c

c

c

If the toilet bowl used with the water tank provided with the water inlet valve sample to be measured is installed close to a wall corner, the position array coordinates of the microphone on the parallelepiped measuring surface are shown in table 3, and the area S is calculated according to the formula (3):

S＝2(2ab+bc+ca)................................................(3)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+0.5d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively, the length, width and height of the reference body of the sound source (length l of the reference body)₁And width l₂I.e. the distance from the two walls to the opposite side of the respective reference body); the measurement distance d is 1.0 m.

TABLE 3 position array coordinates of a parallelepiped measuring surface microphone with intake valve samples on three reflecting planes

Microphone location	1	2	3	4
					x	2a	a	2a	a
y	-b	-2b	－2b	-b
					z	0.5c	0.5c	c	c

The sound pressure level measurement is carried out according to the following steps:

(1) except that 1 test water tank for assembling a water inlet valve sample to be tested and necessary test devices such as a supporting rack and a tripod are reserved, all other articles in the test chamber are removed, and no redundant personnel can be present in the test chamber; the experimental operator must not wear clothing with significant sound absorption characteristics; measuring and recording the air temperature and the atmospheric pressure in the test chamber by using a thermometer and a barometer which are qualified by verification;

(2) before testing a sample of a water inlet valve of a toilet water tank, firstly, measuring the size l of the test water tank by using a steel ruler and a square ruler₁、l₂、l₃And recording; according to the number of reflection planes involved in the installation mode of the matched toilet, determining the space positioning of the sound source reference body and calculating the characteristic dimension d of the sound source reference body₀(ii) a The applicable parallelepiped enveloping sound source measuring surface is selected and its dimensions a, b, c are calculated. Measuring the position array of the surface microphone according to the selected parallelepiped, calculating and recording the coordinates of the measuring points;

(3) the sound level meter used for measurement is required to meet the requirement of a 1-type instrument in GB/T3785.1-2010, and the verification period is not more than 2 years; the filter meets the requirements of a type 1 instrument in IEC 61260:1995, and the calibration period does not exceed 1 year. Before the test is started and after the test is finished, verifying the test on one or more frequencies in the measuring frequency range of the sound level meter by using a sound calibrator meeting the requirement of the level 1 accuracy in GB/T15173; the difference of the readings is not more than 0.5 dB;

(4) the inlet noise test chamber of the inlet valve of the toilet water tank can be a semi-anechoic chamber or a reverberation chamber, so that the available space volume in the test chamber can meet the installation requirements of the test water tank and a support frame thereof, corresponding water supply/drainage conditions are provided, and the dynamic pressure of test water can be regulated and controlled; wherein, the background noise in the semi-silencing chamber is not more than 16dB (A), the acoustic condition of approximate free field above the reflecting surface can be provided, and the verification period is not more than 5 years; background noise in the reverberation room is not more than 25dB (A), and reverberation time is in the range of 5 s-6 s;

(5) in the test chamber meeting the requirements, positioning the coordinates of the measuring points according to the position array of the selected parallelepiped measuring surface microphone; simultaneously moving the tripod to a measuring point position and placing a sound level meter with related acoustic performance on a top tripod head of the tripod to ensure that the orientation of the microphone is the same as the sound wave incident angle when the microphone is calibrated and the microphone vertically points to a measuring surface;

(6) starting timing 10s after the water inlet valve is opened until the water inlet valve is naturally closed, and taking the timing as the integral time of sound level meter audio signal acquisition; if the water replenishing period (half flushing or full flushing) of the sample of the water inlet valve to be tested is less than 30s, the integral time is counted by 20 s. Determination of cumulative percent time-averaged sound pressure level L of background noise on selected parallelepipedal measurement surfaces Using the Slow time-weighted characteristic "S" of the A-weighted equivalent sound level of the Sound level Meter_pAi(B)(50)Measurements were taken 3 times in succession at each microphone location, and the arithmetic mean was taken as the sound pressure level measurement of the background noise at that location and recorded. If the difference of the sound pressure levels measured 3 times at each position is greater than 0.5dB, re-measuring and recording;

(7) adjusting the dynamic pressure of the test to 0.30MPa +/-0.05 MPa, and emptying water in the test water tank according to the water supplement requirement to be tested; timing is started 10s after water is re-fed until the water inlet valve is naturally closed, and the timing is used as the integral time for collecting the audio signal of the sound level meter; if the water replenishing period (half flushing or full flushing) of the sample of the water inlet valve to be tested is less than 30s, the integral time is counted by 20 s. Determining the cumulative percentage time average sound pressure level L 'of the inlet water noise of the toilet cistern inlet valve on the selected parallelepiped measuring surface by using the slow time weighting characteristic S of the A weighting equivalent sound level of the sound level meter'_pAi(ST)(50)The measurements were taken 3 times in succession at each microphone location, and the arithmetic mean was taken as the pressure level measurement of the water ingress noise at that location and recorded. If the difference of the sound pressure level measured 3 times at each position is more than 0.5dB, re-measuring; and simultaneously recording the dynamic pressure, the water supplement amount and the water supplement period of each water inflow.

The sound power level calculation is carried out according to the following steps:

(1) selecting a calculation formula: referring to relevant regulations in GB/T3767-:

if Δ L_pA(50)If the noise is more than 15dB, the background noise correction is not needed; if the value of Delta L is less than or equal to 6dB_p(50)And (5) correcting according to the formula (7) if the value is less than or equal to 15 dB.

K_1A＝-10lg(1-10^{-0.1△LpA(50)})…………………………………………………(7)

K_2A＝l0lg(l+4S/A)…………………………………………………………(8)

When K is_2AWhen the power is less than or equal to 4dB, the measurement made according to the method is effective; wherein, the calculation formulas of the sound absorption quantity of the half anechoic chamber and the reverberation chamber are respectively as follows:

A＝α·S_ν……………………………………………………………………………(9)

A＝0.16V/T_n…………………………………………………………………(10)

L_{WA ref,atm(50)}＝L_WA(50)+C₁+C₂…………………………………………………(15)

in the formula:

-in a specific water replenishing period, measuring the A weighting cumulative percentage time average sound pressure level mean value of inlet water noise of the inlet valve on the parallelepiped measuring surface, the unit being decibel (dB);

L′_pAi(ST)(50)in a specific water replenishing period, the A weighting accumulated percentage time average sound pressure level of the water inlet noise of the water inlet valve, which is measured at the ith microphone position on the parallelepiped measuring surface, is measured in decibels (dB);

N_M-the number of positions of the parallelepiped measuring surface microphone;

-in a specific water replenishment period, the a weighting cumulative percentage time average sound pressure level mean value of the background noise measured on the parallelepiped measurement surface, in decibels (dB);

L_pAi(B)(50)-the back measured at the ith microphone position on the parallelepiped measuring surface during a specific refill cycleThe A weighting of scene noise accumulates the time average sound pressure level of percentage, the unit is decibel (dB);

K_1A-a background noise correction value;

K_2A-testing the environmental correction value;

s-area of the parallelepiped measuring surface in square meters (m)²)；

A-equivalent sound absorption area in square meters (m) of room at 1kHz frequency in test chamber²)；

alpha-A weighted average sound absorption coefficient of the surface of a test room, and the numerical range is shown in A.1 in GB/T3767-2016;

S_νtotal area of the test Room boundary (wall, floor, ceiling) in square meters (m)²)；

V-test Room volume in cubic meters (m)³)；

T_n-measured a weight or frequency band reverberation time in seconds(s);

in a specific water replenishing period, the A weighting accumulated percentage time average sound pressure level of the water inlet noise of the water inlet valve sample measured by a parallelepiped measuring surface method is in decibels (dB);

L_WA(50)under the meteorological conditions of the test time and place, the intake noise A weight-calculated accumulated percentage acoustic power level of each intake valve sample is measured by a parallelepiped measuring surface method in a specific water replenishing period, and the unit is decibel (dB);

S₀＝1m²；

C₁-testing a function of the air characteristic impedance under meteorological conditions of time and place;

C₂-converting the actual acoustic power at meteorological conditions relative to the test time and place into a radiation impedance modification value of the acoustic power at standard meteorological conditions;

p_s——atmospheric pressure at the time and place of the test in kilopascals (kPa);

p_s,0-standard atmospheric pressure, 101.325 kPa;

θ — air temperature at test time and site in degrees Celsius (C.);

θ₀＝314K；

θ₁＝296K；

L_{WA ref,atm(50)}under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the A weight cumulative percentage acoustic power level of the water inlet noise of each water inlet valve sample is in decibel (dB);

-the average value of the a-weighted cumulative percentage acoustic power level of the inlet noise of each set of inlet valve samples in decibels (dB);

L_WA(50)1、L_WA(50)2、L_WA(50)3-a weight cumulative percentage acoustic power level a of inlet noise for each set of three inlet valve samples in decibels (dB);

under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the average value of the A weighted cumulative percentage acoustic power level of the water inlet noise of each group of water inlet valve samples is expressed in decibels (dB);

L_{WA ref,atm(50)1}、L_{WA ref,atm(50)2}、L_{WA ref,atm(50)3}under the standard meteorological conditions of the atmospheric pressure of 101.325kPa and the temperature of 23.0 ℃, the A weighting cumulative percentage acoustic power level of the water inlet noise of each group of water inlet valve samples is in decibel (dB);

(2) data reduction requirements: a weighted cumulative percentage time average sound pressure level L 'of inlet water noise and background noise of toilet cistern water inlet valve'_pAi(ST)(50)And L_pAi(B)(50)The measurement result retains a significant digit after the decimal point, and the mean value thereof

And

and A weight cumulative percentage acoustic power level L of inlet water noise of water inlet valve_WA(50)Taking an integer from the calculation result of (1);

(3) measurement uncertainty: the method prescribes the repeatability standard deviation sigma of the measurement result of the water inlet noise A of the toilet cistern water inlet valve weight accumulation percentage time average sound pressure level on the parallelepiped measurement surface_omcThe upper limit value is not more than 1.5 dB. Referring to the relevant contents in the standard GB/T3767-2016, in a complete water replenishing period, the same experiment personnel uses the same sound level meter to measure the A-weighted cumulative percentage time average sound pressure level average value on the same parallelepiped measuring surface selected by the same toilet water tank inlet valve sample at the same installation position

Or

6 replicate measurements were made (for each replicate the inlet valve sample had to be reinstalled and repositioned) and the measurement was corrected for background noise. Standard deviation of repeatability σ_omcThe calculation formula of (2) is as follows:

in the formula:

the average value of the A weighted cumulative percentage time average sound pressure level on the measuring surface of the parallel hexahedron after the jth repeated measurement of the water inlet noise of the water inlet valve of the toilet cistern and the correction of the background noise;

-arithmetic mean sound pressure level calculated from all repeated measurements.

The result evaluation calculation is carried out according to the following steps:

(1) according to the national environmental protection standard and the standard requirements of related products, the following grading judgment standards are adopted:

the noise of water inlet is very low, and the environmental protection performance is excellent;

the noise of water inlet is low, and the environmental protection performance is good;

the water inlet noise is low, and the environmental protection performance is good;

the flushing noise is high, and the environmental protection performance is poor;

the noise is very high for flushing and the environmental protection performance is poor.

(2) When a certain sample water inlet noise A is weighted, the cumulative percentage sound power level L is calculated_WA(50)The water inflow noise A of 3 samples in the group is weighted and accumulated in percentage acoustic power level L_WA(50)Arithmetic mean value

When the concentration is 10 percent, a group of samples need to be extracted again to repeat the experiment; calculating the slow time weighting characteristic 'S' of the A-weighted equivalent sound level of the front and the rear groups of water inlet valve samples under the set dynamic pressure by applying a sound level meterWater inflow noise A weighting cumulative percentage acoustic power level L measured by measuring surface method_WA(50)Is arithmetic mean of

If a certain sample water inlet noise A is weighted and accumulated the percentage sound power level L_WA(50)The water inlet noise A of more than the two groups of 6 samples is counted and accumulated the percentage sound power level L_WA(50)Arithmetic mean value

10% of the total weight is discarded; the accumulated percentage acoustic power level L is calculated by weighting the water inlet noise A of the rest water inlet valve sample_WA(50)Is an arithmetic mean value of

As the water inlet noise evaluation index of the water inlet valve sample of the toilet water tank.

Drawings

FIG. 1 is a schematic illustration of the relative water levels of the various components within the flush tank;

in the figure: 38mm is more than or equal to h₁≥10mm，h₂≥25mm，h₃≥5mm，h₄≥5mm，h₅≤20mm；

FIG. 2 is a schematic diagram showing the relative water levels of the components inside the concealed water tank;

in the figure: h is₁≥15mm，h₂≥25mm，h₃≥5mm，h₄≥5mm，h₅≤20mm；

FIG. 3 is a schematic view of a water inlet valve inlet noise source reference on a reflective surface of the present invention;

in the figure: d₀-the characteristic size of the sound source, m; l₁-length of reference body, m; l₂-width of the reference body, m; l₃-height of the reference body, m; o-origin of coordinates;

FIG. 4 is a schematic view of the inlet valve feed noise source reference on two reflecting planes in the present invention;

in the figure: d₀-the characteristic size of the sound source, m; l₁Length of reference bodyDegree, m; l₂-width of the reference body, m; l₃-height of the reference body, m; o-origin of coordinates;

FIG. 5 is a schematic view of the inlet valve feed noise source reference on three reflecting planes of the present invention;

in the figure: d₀-the characteristic size of the sound source, m; l₁-length of reference body, m; l₂-width of the reference body, m; l₃-height of the reference body, m; o-origin of coordinates;

FIG. 6 is a schematic view of a parallelepiped measuring surface of a water inlet valve feed noise source on a reflecting plane and its microphone location array of the present invention;

in the figure: ● — microphone position; a-a reflecting surface; b-a reference body; 2 a-measuring surface length, m; 2 b-measuring the surface width m; c-measuring surface height, m; d-measuring distance, m; l₁-reference body length, m; l₂-reference body width, m; l₃-height of reference body, m;

FIG. 7 is a schematic illustration of a parallelepiped measuring surface of a water inlet valve feed noise source and its microphone location array on two reflecting planes in accordance with the present invention;

in the figure: ● — microphone position; b-a reference body; 2 a-measuring surface length, m; 2 b-measuring the surface width, m; c-measuring surface height, m; d-measuring distance, m; l₁-reference body length, m; l₂-reference body width, m; l₃-height of reference body, m;

FIG. 8 is a schematic view of a parallelepiped measuring surface of a water inlet valve feed noise source and its microphone location array on three reflecting planes in accordance with the present invention;

in the figure: ● — microphone position; b-a reference body; 2 a-measuring surface length, m; 2 b-measuring the surface width, m; c-measuring surface height, m; d-measuring distance, m; l₁-reference body length, m; l₂-reference body width, m; l₃-height of reference body, m;

Detailed Description

The invention is described in detail below with reference to the drawings and preferred embodiments so that the advantages and features of the invention can be more easily understood by those skilled in the art, and the scope of the invention is more clearly and clearly defined.

In the embodiment, water inlet valve samples with the use modes of top pressing and double flushing and the nominal water supplement amounts of 6L and 3L respectively are arranged in a flushing water tank matched with a toilet; the detection of the noise of the water inlet under the condition of the full water replenishing quantity is taken as an example for explanation.

The specific detection method comprises the following steps:

(1) sample installation and commissioning

1.1 sample number, Specification

The water inlet valve samples in 3 toilet tank fittings of the same type, specification and size produced by the same manufacturer and the same batch are used as a group, and the use mode can be side pressing or top pressing (single-flushing type or double-flushing type).

1.2 sample mounting

The standard water tank meeting the technical requirements of national standard GB 26730-: 400mm × 175mm × 300 mm; the relative water level of each component of a standard water tank or a flushing water tank (not comprising a concealed water tank) after being installed meets the requirement of item 5.4.1, and the relative water level of each component of the concealed water tank after being installed meets the requirement of item 5.4.10.2.

1.3 sample Conditioning

A water inlet valve sample is installed inside a test water tank according to the use instructions of a production plant, for a water inlet valve provided with a water replenishing device, a water replenishing pipe is firmly fixed on the water inlet valve, the rated water replenishing ratio is marked, and the water replenishing quantity can meet the requirement of water seal recovery of a toilet. According to the regulations of No. 5.2.3, No. 5.2.4 and No. 5.2.8 in GB 26730-; after static pressure and dynamic pressure tightness tests, the rising height of the water level of the water tank is not more than 8mm, and no visible drip leakage exists after the water inlet valve is closed; when the water is drained to a specified height, the water inlet valve can be automatically opened, the water can be automatically closed after the water is fed to a working water level, and the height difference of the working water level of the continuous 5-time water feeding is not more than 5 mm. The relative water levels of the flush tank (not including the concealed tank) after the components are installed should meet the requirements of figure 1, and the relative water levels of the concealed tank after the components are installed should meet the requirements of figure 2.

1.4 sample positioning

1.4.1 when the toilet bowl matched with the water tank provided with the water inlet valve sample to be tested is not installed close to any wall, if the test is carried out in the acoustic environment similar to the free field above the reflecting surface of the semi-anechoic chamber, the test water tank can be directly placed in the center of the ground through the supporting frame without adding a water tank cover; the height of the bottom of the water tank from the indoor ground is 450mm, and the normal flushing function is ensured. If the test is carried out in a rigid wall test chamber or a special reverberation chamber, the test water tank can be placed on the ground through the supporting rack without adding a water tank cover; the height from the bottom of the water tank to the indoor ground is 450mm, and the distance between the water tank and any wall in the room is not less than 1.0 m; while ensuring proper flushing function.

1.4.2 when the toilet bowl matched with the water tank provided with the inlet valve sample to be tested is installed against a wall, the toilet bowl can be tested in a rigid wall surface test chamber or a special reverberation chamber, and the test water tank is directly placed on the ground through the support frame without adding a water tank cover; the height from the bottom of the water tank to the indoor ground is 450mm, the distance between the back of the water tank and the wall against which the water tank leans is 15cm +/-5 cm, and the distance between the water tank and the other three indoor walls is not less than 1.5 m; while ensuring proper flushing function.

1.4.3 when the toilet bowl matched with the water tank provided with the inlet valve sample to be tested is installed by a corner, the toilet bowl can be tested in a rigid wall test chamber or a special reverberation chamber, and the test water tank is directly placed on the ground through the support frame without adding a water tank cover; the height from the bottom of the water tank to the indoor ground is 450mm, the distance between the back and the side of the water tank and the wall is 15cm +/-5 cm, and the distance between the water tank and the other two indoor walls is not less than 1.5 m; and meanwhile, the normal flushing function is ensured.

(2) Determination of a reference body for a sound source and a parallelepiped measuring surface

2.1 determination of the shape and size of the Water intake noise Source reference

Setting the position and the size of a sound source reference body by using a three-dimensional coordinate system according to the relevant regulations of item 7.1 in GB/T3767-2016 engineering method for measuring sound power level of a noise source and approximate free field above a sound energy level reflecting surface by an acoustic sound pressure method; aiming at different installation modes of a ceramic toilet bowl matched with a water tank for assembling a water inlet valve sample to be tested, the center of a box body formed by a sound source reference body and mirror images of the sound source reference body on adjacent reflecting planes is used as a coordinate origin O, and a horizontal axis x and a horizontal axis y are respectively parallel to the length and the width of the reference body. Length l using horizontal width of test water tank as sound source reference body₁And the width l taking the horizontal length of the test water tank as the sound source reference body₂And the vertical distance between the working water level line of the test water tank and the ground is taken as the height l of the sound source reference body₃. Characteristic dimension d of sound source reference body corresponding to different test environment conditions₀Are respectively [ (l)₁/2)²+(l₂/2)²+l₃ ²]^1/2(a reflection plane), [ l [ ]₁ ²+(l₂/2)²+l₃ ²]^1/2(two reflection planes) and [ l₁ ²+l₂ ²+l₃ ²]^1/2(three reflection planes) in meters (m).

2.2 selection of the parallelepiped measuring surface and determination of the microphone position array

Determination of the parallelepiped measuring surface and its microphone position array: according to the relevant regulations of 7.2.4 th and 8.1.2 th items in the standard GB/T3767-2016, a parallelepiped measuring surface adopted in the test and a sound source reference body have the same-oriented coordinate origin and appearance shape, namely an imaginary parallelepiped with the area of S, enveloping the water inlet noise source of the water inlet valve to be tested, and the distance between each side of the imaginary parallelepiped measuring surface and the reference body of d, wherein d is more than or equal to 1.0 m.

2.2.1 if the toilet bowl used with the water tank provided with the inlet valve sample to be measured is installed, the positioning is carried out according to item 1.4.1 in the embodiment, the corresponding parallelepiped measuring surface and the microphone position array thereof are shown in fig. 4, the coordinate of the measuring point is shown in table 1, wherein the measuring distance d is 1.0 m; the area S of the measurement surface is calculated according to equation (1):

S＝4(ab+bc+ca)...................................................(1)

in the formula: a is 0.5l₁+d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively the length, width and height of the sound source reference body.

TABLE 1 parallelepiped measuring surface microphone position array coordinates with water inlet valve samples on one reflection plane

Microphone location

1

2

3

4

5

6

7

8

9

x

a

0

－a

0

a

－a

－a

a

0

y

0

b

0

－b

b

b

－b

－b

0

z

0.5c

0.5c

0.5c

0.5c

c

c

c

c

c

2.2.2 if the toilet bowl used with the water tank provided with the inlet valve sample to be measured is installed, the positioning is carried out according to item 1.4.2 in the embodiment, the corresponding parallelepiped measuring surface and the microphone position array thereof are shown in fig. 5, the coordinate of the measuring point is shown in table 2, wherein the measuring distance d is 1.0 m; the area S of the measurement surface is calculated according to equation (2):

S＝2(2ab+bc+2ca).................................................(2)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively, the length (distance from the wall to the front end face), width and height of the sound source reference body.

TABLE 2 parallelepiped Measure surface microphone position array coordinates with intake valve samples on two reflection planes

Microphone location

1

2

3

4

5

6

x

2a

a

a

2a

2a

a

y

0

b

－b

b

-b

0

z

0.5c

0.5c

0.5c

c

c

c

2.2.3 if the toilet bowl used with the water tank provided with the inlet valve sample to be measured is installed, the positioning is carried out according to item 1.4.3 in the embodiment, the corresponding parallelepiped measuring surface and the microphone position array thereof are shown in fig. 6, the coordinate of the measuring point is shown in table 3, wherein the measuring distance d is 1.0 m; the area S of the measurement surface is calculated according to equation (3):

S＝2(2ab+bc+ca)................................................(3)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+0.5d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively, the length, width and height of the reference body of the sound source (length l of the reference body)₁And width l₂I.e., the distance from the two walls to the opposite side of the respective datum body).

TABLE 3 position array coordinates of a parallelepiped measuring surface microphone with intake valve samples on three reflecting planes

Microphone location	1	2	3	4
					x	2a	a	2a	a
y	-b	-2b	－2b	-b
					z	0.5c	0.5c	c	c

(3) Sound pressure level measurement

3.1 except that 1 test water tank for assembling a water inlet valve sample to be tested and necessary experimental apparatuses such as a supporting rack and a tripod thereof are reserved, all other articles in the test chamber are removed, and no redundant personnel can be present in the test chamber; the experimental operator must not wear clothing with significant sound absorption characteristics; the air temperature and atmospheric pressure in the test chamber were measured and recorded using certified thermometers and barometers.

3.2 before testing the inlet valve sample of the toilet water tank, firstly, measuring the dimension l of the test water tank by using a steel ruler and a square ruler₁、l₂、l₃And recording; according to the number of reflection planes involved in the installation mode of the matched toilet, determining the space positioning of the sound source reference body and calculating the characteristic dimension d of the sound source reference body₀(ii) a The applicable parallelepiped enveloping sound source measuring surface is selected and its dimensions a, b, c are calculated. And (4) measuring the surface microphone position array according to the selected parallelepiped, calculating the coordinates of the measuring points and recording the coordinates.

3.3 the sound level meter used for measurement is in accordance with the requirement of a 1-type instrument in GB/T3785.1-2010, and the verification period is not more than 2 years; the filter meets the requirements of a type 1 instrument in IEC 61260:1995, and the calibration period does not exceed 1 year. Before the beginning and after the end of each test, a sound calibrator meeting the requirement of 1-level accuracy in GB/T15173 is used for verifying the test on one or more frequencies in the measurement frequency range of the sound level meter; the difference in readings is no greater than 0.5 dB.

3.4 the inlet noise test chamber of the inlet valve of the toilet water tank can be a semi-anechoic chamber or a reverberation chamber, so that the available space volume in the test chamber can meet the installation requirements of the test water tank and a support frame thereof, corresponding water supply/drainage conditions are provided, and the dynamic pressure of test water can be regulated and controlled; wherein, the background noise in the semi-silencing chamber is not more than 16dB (A), the acoustic condition of approximate free field above the reflecting surface can be provided, and the verification period is not more than 5 years; the background noise in the reverberation room is not more than 25dB (A), and the reverberation time is in the range of 5 s-6 s.

3.5 in the test chamber meeting the requirements, positioning the coordinates of the measuring points according to the position array of the selected parallelepiped measuring surface microphone; and meanwhile, the tripod is moved to a measuring point position, and the sound level meter with relevant acoustic performance is placed on the top tripod head, so that the microphone is ensured to be oriented to have the same sound wave incidence angle when being calibrated and point to the measuring surface vertically.

3.6 starting timing 10s after the water inlet valve is opened until the water inlet valve is naturally closed, and taking the timing as the integral time of sound level meter audio signal acquisition; if the water replenishing period (half flushing or full flushing) of the sample of the water inlet valve to be tested is less than 30s, the integral time is counted by 20 s. Applications ofSlow time weighting characteristic "S" of A-weighted equivalent sound level of a sound level meter determines the cumulative percent time average sound pressure level L of background noise on a selected parallelepipedal measurement surface_pAi(B)(50)Measurements were taken 3 times in succession at each microphone location, and the arithmetic mean was taken as the sound pressure level measurement of the background noise at that location and recorded. If the difference between the sound pressure levels measured 3 times at each location is greater than 0.5dB, the measurements are re-measured and recorded.

3.7 adjusting the dynamic pressure of the test to 0.30MPa +/-0.05 MPa, and emptying the water in the test water tank according to the water supplement requirement to be detected; timing is started 10s after water is re-fed until the water inlet valve is naturally closed, and the timing is used as the integral time for collecting the audio signal of the sound level meter; if the water replenishing period (half flushing or full flushing) of the sample of the water inlet valve to be tested is less than 30s, the integral time is counted by 20 s. Determining the cumulative percentage time average sound pressure level L 'of the inlet water noise of the toilet cistern inlet valve on the selected parallelepiped measuring surface by using the slow time weighting characteristic S of the A weighting equivalent sound level of the sound level meter'_pAi(ST)(50)The measurements were taken 3 times in succession at each microphone location, and the arithmetic mean was taken as the pressure level measurement of the water ingress noise at that location and recorded. If the difference of the sound pressure level measured 3 times at each position is more than 0.5dB, re-measuring; and simultaneously recording the dynamic pressure, the water supplement amount and the water supplement period of each water inflow.

(4) Calculation of results

4.1 selection of calculation formula: referring to the relevant specifications in GB/T3767-:

if Δ L_pA(50)If the noise is more than 15dB, the background noise correction is not needed; if the value of Delta L is less than or equal to 6dB_p(50)And (5) correcting according to the formula (7) if the value is less than or equal to 15 dB.

K_1A＝-10lg(1-10^{-0.1△LpA(50)})…………………………………………………(7)

K_2A＝l0lg(l+4S/A)…………………………………………………………………(8)

When K is_2AWhen the power is less than or equal to 4dB, the measurement made according to the method is effective; wherein, the calculation formulas of the sound absorption quantity of the half anechoic chamber and the reverberation chamber are respectively as follows:

A＝α·S_ν……………………………………………………………………………(9)

A＝0.16V/T_n…………………………………………………………………(10)

L_{WA ref,atm(50)}＝L_WA(50)+C₁+C₂……………………………………………………(15)

in the formula:

-in a specific water replenishing period, measuring the A weighting cumulative percentage time average sound pressure level mean value of inlet water noise of the inlet valve on the parallelepiped measuring surface, the unit being decibel (dB);

L′_pAi(ST)(50)in a specific water replenishing period, the A weighting accumulated percentage time average sound pressure level of the water inlet noise of the water inlet valve, which is measured at the ith microphone position on the parallelepiped measuring surface, is measured in decibels (dB);

N_M-the number of positions of the parallelepiped measuring surface microphone;

-in a specific water replenishment period, the a weighting cumulative percentage time average sound pressure level mean value of the background noise measured on the parallelepiped measurement surface, in decibels (dB);

L_pAi(B)(50)-in a specific water replenishment period, measuring the A weighted cumulative percentage time average sound pressure level of the background noise at the ith microphone position on the parallelepiped measurement surface in decibels (dB);

K_1A-a background noise correction value;

K_2A-testing the environmental correction value;

s-area of the parallelepiped measuring surface in square meters (m)²)；

A-equivalent sound absorption area in square meters (m) of room at 1kHz frequency in test chamber²)；

alpha-A weighted average sound absorption coefficient of the surface of a test room, and the numerical range is shown in A.1 in GB/T3767-2016;

S_νtotal area of the test Room boundary (wall, floor, ceiling) in square meters (m)²)；

V-test Room volume in cubic meters (m)³)；

T_n-measured a weight or frequency band reverberation time in seconds(s);

in a specific water replenishing period, the A weighting accumulated percentage time average sound pressure level of the water inlet noise of the water inlet valve sample measured by a parallelepiped measuring surface method is in decibels (dB);

L_WA(50)under the meteorological conditions of the test time and place, the intake noise A weight-calculated accumulated percentage acoustic power level of each intake valve sample is measured by a parallelepiped measuring surface method in a specific water replenishing period, and the unit is decibel (dB);

S₀＝1m²；

C₁-testing a function of the air characteristic impedance under meteorological conditions of time and place;

C₂-converting the actual acoustic power at meteorological conditions relative to the test time and place into a radiation impedance modification value of the acoustic power at standard meteorological conditions;

p_s-atmospheric pressure at the test time and location in kilopascals (kPa);

p_s,0-standard atmospheric pressure, 101.325 kPa;

θ — air temperature at test time and site in degrees Celsius (C.);

θ₀＝314K；

θ₁＝296K；

L_{WA ref,atm(50)}under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the A weight cumulative percentage acoustic power level of the water inlet noise of each water inlet valve sample is in decibel (dB);

-the average value of the a-weighted cumulative percentage acoustic power level of the inlet noise of each set of inlet valve samples in decibels (dB);

L_WA(50)1、L_WA(50)2、L_WA(50)3-a weight cumulative percentage acoustic power level a of inlet noise for each set of three inlet valve samples in decibels (dB);

under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the average value of the A weighted cumulative percentage acoustic power level of the water inlet noise of each group of water inlet valve samples is expressed in decibels (dB);

L_{WA ref,atm(50)1}、L_{WA ref,atm(50)2}、L_{WA ref,atm(50)3}under the standard meteorological conditions of the atmospheric pressure of 101.325kPa and the temperature of 23.0 ℃, the A weighting cumulative percentage acoustic power level of the water inlet noise of each group of the water inlet valve samples is in decibel (dB).

4.2 data reduction requirements: a weighted cumulative percentage time average sound pressure level L 'of inlet water noise and background noise of toilet cistern water inlet valve'_pAi(ST)(50)And L_pAi(B)(50)The measurement result retains a significant digit after the decimal point, and the mean value thereof

And

and A weight cumulative percentage acoustic power level L of inlet water noise of water inlet valve_WA(50)The calculation result of (2) is an integer.

4.3 measurement uncertainty: the method prescribes the repeatability standard deviation sigma of the measurement result of the water inlet noise A of the toilet cistern water inlet valve weight accumulation percentage time average sound pressure level on the parallelepiped measurement surface_omcThe upper limit value is not more than 1.5 dB. The related contents in reference standard GB/T3767-2016 are added to a complete water supplementIn the period, the same experimenter uses the same sound level meter to measure the average value of the A weighted cumulative percentage time average sound pressure level on the same parallelepiped measuring surface selected by the same toilet cistern water inlet valve sample at the same installation position

Or

6 replicate measurements were made (for each replicate the inlet valve sample had to be reinstalled and repositioned) and the measurement was corrected for background noise. Standard deviation of repeatability σ_omcThe calculation formula of (2) is as follows:

in the formula:

the average value of the A weighted cumulative percentage time average sound pressure level on the measuring surface of the parallel hexahedron after the jth repeated measurement of the water inlet noise of the water inlet valve of the toilet cistern and the correction of the background noise;

-arithmetic mean sound pressure level calculated from all repeated measurements.

(5) Performance determination

5.1 according to the national environmental protection standard and the relevant product standard requirements, adopting the following grading judgment standards:

the noise of water inlet is very low, and the environmental protection performance is excellent;

the noise of water inlet is low, and the environmental protection performance is good;

the water inlet noise is low, and the environmental protection performance is good;

the flushing noise is high, and the environmental protection performance is poor;

the noise is very high for flushing and the environmental protection performance is poor.

5.2 when a certain sample water inlet noise A counts the weight and accumulates the percentage sound power level L_WA(50)The water inflow noise A of 3 samples in the group is weighted and accumulated in percentage acoustic power level L_WA(50)Arithmetic mean value

When the concentration is 10 percent, a group of samples need to be extracted again to repeat the experiment; calculating the slow time weighting characteristic S of the equivalent sound level of the A weighting of the sound level meter applied to the front and the back groups of water inlet valve samples under the set dynamic pressure by using the A weighting cumulative percentage sound power level L of the water inlet noise A weighting measured by a parallelepiped measuring surface method_WA(50)Is arithmetic mean of

If a certain sample water inlet noise A is weighted and accumulated the percentage sound power level L_WA(50)The water inlet noise A of more than the two groups of 6 samples is counted and accumulated the percentage sound power level L_WA(50)Arithmetic mean value

10% of the total weight is discarded; the accumulated percentage acoustic power level L is calculated by weighting the water inlet noise A of the rest water inlet valve sample_WA(50)Is an arithmetic mean value of

As the water inlet noise evaluation index of the water inlet valve sample of the toilet water tank.

Test facilities, instrumentation and test equipment used in this example:

(1) test facility

Semi-anechoic chamber: the net size of the indoor building is 9.8m multiplied by 7.3m multiplied by 5.9m, the effective space size after the sound-absorbing wedge is hung is 7.8m multiplied by 5.3m multiplied by 4.9m, and the effective volume is 203m³Effective usable area of 41m². The ceramic tile floor is taken as a single reflecting plane, and no other fixed facilities are needed in a room except for the corresponding water supply/drainage pipeline and the air conditioner; when the laboratory works normally and the periphery has no abnormal interference, the indoor background noise is lower than 14.1dB (A); the degree of uncertainty of the spread of the sound pressure level measurement is U₉₅＝(0.4～1.0)dB，k＝2。

(2) Test equipment and equipment

2.1 Sound level Meter: the model is NA-28 and can measure equivalent continuous sound pressure L produced by Japan rational sound company_eqThe performance meets the regulation of a 1-type integral sound level meter in GB/T3785, and the filter meets the requirement of GB 3241; the sensitivity of a preamplifier of the noise analyzer is-27 dB +/-2 dB, the A-weighted linear operation range is 25 dB-130 dB, the upper limit of peak sound level measurement is 143dB, the maximum value of inherent noise A weight is 17dB, the measurement frequency range is 10 Hz-20 kHz, and the sampling period is 15.6 ms. Before each measurement, a sound calibrator with the accuracy of +/-0.1 dB is adopted to select 100Hz, 300Hz, 500Hz, 700Hz, 900Hz, 1000Hz and the like points in the test frequency range to carry out overall verification on the related noise measurement system.

The sound pressure level uncertainty U is 0.4dB to 1.0dB (k is 2); the sound pressure level uncertainty U at the reference frequency is 0.07dB (k is 2); the uncertainty of the calibration result is 1.0dB (k 2).

2.2 sound calibrator: the model AWA6221A produced by hundred million Europe instrument equipment Limited company is used for absolute sound pressure calibration of a sound level meter, and the acoustic performance meets the 1-level accuracy requirement in GB/T15173; the nominal sound pressure level is 94dB and 114dB (taking 20 mu Pa as a benchmark), the applicable frequency range is 1 kHz-5 Hz, the sound pressure level accuracy is +/-0.2 dB (23 ℃) and +/-0.3 dB (-10 ℃ -50 ℃), and the total harmonic distortion is less than or equal to 1% when the sound pressure level is 94 dB.

2.3 ruler: a straight steel ruler and a square ruler with the division value of 1 mm.

2.4 thermometer: the measuring range is 0 DEG C

The index value is 0.2 ℃.

2.5 empty cell barometer: the measurement range is 800hPa to 1060hPa, and the maximum allowable error of the value is +/-1.0 hPa.

2.6 stopwatch: the accuracy was 0.01 s.

2.7 tripod: the carbon fiber or aluminum alloy material bears more than 10kg and contains the maximum height of the holder of 2.0 m.

The detection data and result calculation of this embodiment:

in the semi-muffling chamber, the parallelepipedic surface measurement method is applied to test the water inlet noise of the water inlet valve sample in the flushing water tank which is not installed close to any wall, and the related detection data and result evaluation are shown in table 4.

TABLE 4 Inlet valve noise measurement data (parallelepiped measuring surface method of a reflecting plane)

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent modifications made by the contents of the specification and the drawings, or applied directly or indirectly to other related technical fields, are included in the scope of the present invention.

Claims (5)

1. A method for detecting the water inlet noise of a water inlet valve of a toilet cistern comprises the following steps: (1) installing and debugging a sample; (2) sound source baseDetermining a quasi body and a parallelepiped measuring surface; (3) sound pressure level measurement; (4) calculating sound power level and correcting background noise, test environment and meteorological conditions; (5) evaluating the detection result; it is characterized by that it uses sound level meter A to weight the slow time weighting characteristic "S" of equivalent sound level to make the cumulative percentage sound power level L on the parallelepiped measuring surface_WA(50)Accurate quantitative determination is carried out to the noise of intaking of stool pot water tank water intaking valve of sign, and is specific:

in sound pressure level measurement:

(1) before measuring the water inlet noise of a toilet water tank water inlet valve in a semi-anechoic chamber or a reverberation chamber, determining the positioning of a sound source reference body under different reflection plane conditions and calculating the characteristic dimension d of the sound source according to the GB/T3767-2016 engineering method for measuring the sound power level of a noise source and the approximate free field above a sound energy level reflection surface by an acoustic sound pressure method aiming at the typical installation requirements of various toilet water tank water inlet valve samples₀(ii) a Simultaneously selecting a parallelepiped measuring surface corresponding to the water inlet noise source reference body of the water inlet valve, determining the size of the parallelepiped measuring surface, and determining the coordinates of microphone position arrays of different measuring surfaces;

(2) in a semi-anechoic chamber or a reverberation chamber, the water replenishing period of a water inlet valve of a toilet water tank is used as the integral time of audio signal acquisition, and the accumulated percentage time average sound pressure level L of the background noise on the measuring surface of the selected parallelepiped is measured by using the slow time weighting characteristic S of the A weighting equivalent sound level of a sound level meter_pAi(B)(50)(ii) a Then starting a water replenishing device of a water inlet valve under the test dynamic pressure condition of 0.30MPa +/-0.05 MPa; aiming at different water replenishing quantity test requirements of a toilet water tank, in a water replenishing period, determining the accumulated percentage time average sound pressure level L 'of the water inlet noise of a water inlet valve on the selected parallelepiped measuring surface by using the slow time weighting characteristic S of the weighting equivalent sound level A of a sound level meter'_pAi(ST)(50)；

In the acoustic power level calculation:

according to GB/T3767-A weight cumulative percentage time average sound pressure level L 'of intake noise and background noise'_pAi(ST)(50)And L_pAi(B)(50)As the basic data, calculating the corresponding time-averaged sound pressure level mean value

And

and correcting value K for background noise_1ATesting environment correction value K_2AAnd weather condition correction value C₁、C₂Analyzing the influence of the sound waves, and deducing the A-weighted cumulative percentage acoustic power level L of the water inlet noise of each toilet cistern inlet valve sample under the condition of the set dynamic pressure_WA(50)And the average value of the water inlet noise A weight cumulative percentage acoustic power level of each group of samples

Simultaneously, defining corresponding data reduction requirements and measurement uncertainty ranges;

the sound power level calculation is carried out according to the following steps:

(1) selecting a calculation formula: referring to GB/T3767-2016, the calculation formula of the related test parameters is as follows:

if Δ L_pA(50)If the noise is more than 15dB, the background noise correction is not needed; if the value of Delta L is less than or equal to 6dB_p(50)Less than or equal to 15dB, thenThe correction is made according to equation (4):

K_1A＝-10lg(1-10^{-0.1△LpA(50)}) (4)

K_2A＝l0lg(l+4S/A) (5)

when K is_2AWhen the power is less than or equal to 4dB, the measurement made according to the method is effective; wherein, the calculation formulas of the sound absorption quantity of the half anechoic chamber and the reverberation chamber are respectively as follows:

A＝α·S_ν (6)

A＝0.16V/T_n (7)

L_{WA ref,atm(50)}＝L_WA(50)+C₁+C₂ (12)

in the formula:

-in the water replenishment period, the a weight cumulative percentage time average sound pressure level mean value of inlet water noise of the inlet valve measured on the parallelepiped measurement surface is in dB;

L′_pAi(ST)(50)in the water replenishing period, the A weighting accumulated percentage time average sound pressure level of the water inlet noise of the water inlet valve, which is measured at the ith microphone position on the parallelepiped measuring surface, is dB;

N_M-the number of positions of the parallelepiped measuring surface microphone;

-in the water replenishment period, the a weight cumulative percentage time average sound pressure level mean value of the background noise measured on the parallelepiped measurement surface, in dB;

L_pAi(B)(50)in the water replenishing period, the A weight cumulative percentage time average sound pressure level of the background noise measured at the ith microphone position on the parallelepiped measuring surface is in dB;

K_1A-a background noise correction value;

K_2A-testing the environmental correction value;

s-area of the parallelepiped measuring surface in m²；

A-equivalent sound absorption area in unit of m of room at 1kHz frequency in test chamber²；

alpha-A weighted average sound absorption coefficient of the surface of a test room, and the numerical range is shown in A.1 in GB/T3767-2016;

S_ν-total area of room boundaries of the test chamber, the room boundaries comprising walls, floor, ceiling, in m²；

V-testRoom volume in m³；

T_n-measured a weight or frequency band reverberation time in units s;

in the water replenishing period, the A weight of the water inlet noise of the water inlet valve sample measured by the parallelepiped measuring surface method is accumulated to form a percentage time average sound pressure level, and the unit is dB;

L_WA(50)under the meteorological conditions of the test time and place, the water inlet noise A weight of each water inlet valve sample is measured by a parallelepiped measuring surface method in the water replenishing period, and the unit is dB;

S₀＝1m²；

C₁-testing a function of the air characteristic impedance under meteorological conditions of time and place;

C₂-converting the actual acoustic power at meteorological conditions relative to the test time and place into a radiation impedance modification value of the acoustic power at standard meteorological conditions;

p_satmospheric pressure at the test time and location in kPa;

p_s,0-standard atmospheric pressure, 101.325 kPa;

θ -air temperature at test time and site in units of;

θ₀＝314K；

θ₁＝296K；

L_{WA ref,atm(50)}under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the A weight cumulative percentage acoustic power level of the water inlet noise of each water inlet valve sample is dB;

-the average value of the A weighting cumulative percentage acoustic power level of the inlet water noise of each group of inlet valve samples, in dB;

L_WA(50)1、L_WA(50)2、L_WA(50)3the A weighting cumulative percentage acoustic power level of the water inlet noise of each group of three water inlet valve samples is in dB;

under the standard meteorological conditions that the atmospheric pressure is 101.325kPa and the temperature is 23.0 ℃, the average value of the A weighted cumulative percentage acoustic power level of the water inlet noise of each group of water inlet valve samples is dB;

L_{WA ref,atm(50)1}、L_{WA ref,atm(50)2}、L_{WA ref,atm(50)3}under the standard meteorological conditions of the atmospheric pressure of 101.325kPa and the temperature of 23.0 ℃, the A weighting cumulative percentage acoustic power level of the water inlet noise of each group of water inlet valve samples is dB;

(2) data reduction requirements: a weight cumulative percentage time average sound pressure level L 'of inlet water noise and background noise of toilet water tank inlet valve'_pAi(ST)(50)And L_pAi(B)(50)The measurement result retains a significant digit after the decimal point, and the mean value thereof

And

and A weight cumulative percentage acoustic power level L of inlet water noise of water inlet valve_WA(50)Taking an integer from the calculation result of (1);

(3) measurement uncertainty: the method specifies the repeatability standard deviation sigma of the measurement result of the water inlet noise A weight-accumulation percentage time average sound pressure level of the toilet cistern water inlet valve on the parallelepiped measurement surface_omcThe upper limit value is not more than 1.5dB, the reference standard GB/T3767-

Or

6 times of repeated measurement are carried out, for each repeated measurement, the water inlet valve sample needs to be installed again, adjusted and positioned, and background noise correction is carried out on the measurement result; standard deviation of repeatability σ_omcThe calculation formula of (2) is as follows:

in the formula:

-the average value of the A weighted cumulative percentage time average sound pressure level on the parallelepiped measuring surface after j times of repeated measurement of the inlet water noise of the toilet cistern inlet valve and correction by the background noise;

-an arithmetic mean sound pressure level calculated from all repeated measurements;

in the evaluation of the results:

when a certain sample water inlet noise A is weighted, the cumulative percentage sound power level L is calculated_WA(50)The water inflow noise A of 3 samples in the group is weighted and accumulated in percentage acoustic power level L_WA(50)Arithmetic mean value

When 10%, a group of samples need to be extracted again to repeat the experiment; and calculating the water inlet noise accumulated percentage sound power level L of the A weighted equivalent sound level of the sound level meter under the condition of the set dynamic pressure by using the slow time weighted characteristic S of the A weighted equivalent sound level of the sound level meter through the parallelepiped measuring surface method_WA(50)Is arithmetic mean of

If a certain sample water inlet noise A is weighted and accumulated the percentage sound power level L_WA(50)The water inlet noise A of more than the two groups of 6 samples is counted and accumulated the percentage sound power level L_WA(50)Arithmetic mean value

10% of the total weight is discarded; the accumulated percentage acoustic power level L is calculated by weighting the water inlet noise A of the rest water inlet valve sample_WA(50)Is arithmetic mean of

The water inlet noise is used as the evaluation index of the water inlet noise of the water inlet valve sample of the toilet water tank.

2. The method for detecting the water inlet noise of the water inlet valve of the toilet tank according to claim 1, wherein the sample is installed and debugged according to the following steps:

(1) taking 3 water inlet valve samples of toilet water tank fittings of the same type, specification and size produced by the same manufacturer and the same batch as a group, wherein the use mode can be side pressing or top pressing, single-flushing type or double-flushing type;

(2) the standard water tank meeting the technical requirements of national standard GB 26730 plus 2011 gravity type flushing device and sanitary ware rack for the toilet or the flushing water tank meeting the use requirements of the toilet is prepared, and the size of the inner cavity of the standard water tank is length multiplied by width multiplied by height: 400mm × 175mm × 300 mm; the relative water level of each part of the standard water tank or the flushing water tank after being installed meets the requirement of item 5.4.1, and the relative water level of each part of the hidden water tank after being installed meets the requirement of item 5.4.10.2;

(3) installing a water inlet valve sample inside a test water tank according to the use instruction of a production plant, and for a water inlet valve provided with a water supplementing device, firmly fixing a water supplementing pipe on the water inlet valve and marking a rated water supplementing ratio, wherein the water supplementing quantity can meet the water seal recovery requirement of a toilet; according to the regulations of 5.2.3, 5.2.4 and 5.2.8 in GB 26730-; after static pressure and dynamic pressure tightness tests, the rising height of the water level of the water tank is not more than 8mm, and no visible drip leakage exists after the water inlet valve is closed; when the water is drained to a specified height, the water inlet valve can be automatically opened, the water can be automatically closed after the water is fed to a working water level, and the height difference of the working water level of the water fed for 5 times is not more than 5 mm;

(4) when the toilet bowl matched with the water tank provided with the water inlet valve sample to be tested is not installed close to any wall, if the test is carried out in the acoustic environment similar to the free field above the reflecting surface of the semi-anechoic chamber, the test water tank can be directly placed in the center of the ground through the supporting frame without adding a water tank cover; the height between the bottom of the water tank and the indoor ground is 450mm, and the normal flushing function is ensured; if the test is carried out in a rigid wall test chamber or a special reverberation chamber, the test water tank can be placed on the ground through the supporting rack without adding a water tank cover; the height from the bottom of the water tank to the indoor ground is 450mm, and the distance between the water tank and any wall in the room is not less than 1.0 m; meanwhile, the normal flushing function is ensured;

(5) when the toilet bowl matched with the water tank provided with the water inlet valve sample to be tested is installed close to a wall, the test can be carried out in a rigid wall surface test chamber or a special reverberation chamber, the test water tank is directly placed on the ground through the supporting rack, and a water tank cover is not added; the height from the bottom of the water tank to the indoor ground is 450mm, the distance between the back of the water tank and the wall against which the water tank leans is 15cm +/-5 cm, and the distance between the water tank and the other three indoor walls is not less than 1.5 m; meanwhile, the normal flushing function is ensured;

(6) when the pedestal pan matched with the water tank provided with the water inlet valve sample to be tested is installed by a corner, the pedestal pan can be tested in a rigid wall test chamber or a special reverberation chamber, the test water tank is directly placed on the ground through the support frame, and a water tank cover is not added; the height from the bottom of the water tank to the indoor ground is 450mm, the distance between the back and the side of the water tank and the wall against which the water tank leans is 15cm +/-5 cm, and the distance between the water tank and the other two indoor walls is not less than 1.5 m; while ensuring proper flushing function.

3. The method for detecting the water inlet noise of the water inlet valve of the toilet tank as claimed in claim 1, wherein the determination of the sound source reference body and the parallelepiped measuring surface is performed by the following steps:

(1) determination of the shape and the size of the water inlet noise source reference body of the water inlet valve: setting the position and size of a sound source reference body by using a three-dimensional coordinate system according to item 7.1 in GB/T3767-2016 engineering method for measuring sound power level and approximate free field above a sound energy level reflecting surface by an acoustic sound pressure method; aiming at different installation modes of a ceramic toilet bowl matched with a water tank for assembling a water inlet valve sample to be tested, the center of a box body formed by a sound source reference body and mirror images of the sound source reference body on adjacent reflecting planes is taken as a coordinate origin O, and a horizontal axis x and a horizontal axis y are respectively parallel to the length and the width of the reference body; length l of sound source reference body using horizontal width of test water tank₁And the width l taking the horizontal length of the test water tank as the sound source reference body₂And the height l taking the vertical distance from the working water level line of the test water tank to the ground as a sound source reference body₃(ii) a Characteristic dimension d of sound source reference body under one reflection plane condition corresponding to different test environment conditions₀Is [ (l)₁/2)²+(l₂/2)²+l₃ ²]^1/2Characteristic dimension d of sound source reference body under two reflection planes₀Is [ l ]₁ ²+(l₂/2)²+l₃ ²]^1/2Characteristic dimension d of sound source reference body under three reflection planes₀Is [ l ]₁ ²+l₂ ²+l₃ ²]^1/2In the unit of m;

(2) determination of the parallelepiped measuring surface and its microphone position array: according to 7.2.4 th and 8.1.2 th items in the standard GB/T3767-2016, a parallelepiped measuring surface adopted in the test and a sound source reference body have the same azimuth coordinate origin and appearance shape, namely an imaginary parallelepiped with the area of S, enveloping the water inlet noise source of the water inlet valve to be measured, and the distance between each side of the imaginary parallelepiped measuring surface and the reference body being d, wherein d is more than or equal to 1.0 m;

if the toilet bowl used with the water tank provided with the water inlet valve sample to be measured is not close to any wall when being installed, the microphone position array coordinates (x, y, z) on the parallelepiped measuring surface are (a,0,0.5c), (0, b,0.5c), (-a,0,0.5c), (0, -b,0.5c), (a, b, c), (-a, b, c), (a, -b, c), (-a, -b, c), (0,0, c), respectively, and the area S is calculated according to the formula (1):

S＝4(ab+bc+ca) (1)

in the formula: a is 0.5l₁+d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Respectively the length, width and height of the sound source reference body; measuring the distance d to be 1.0 m;

if the toilet bowl matched with the water tank provided with the water inlet valve sample to be detected is installed close to a wall, the microphone position array coordinates (x, y, z) of the parallelepiped measuring surface are (2a,0,0.5c), (a, b,0.5c), (a, -b,0.5c), (2a, b, c), (2a, -b, c), (a,0, c), respectively, and the area S is calculated according to the formula (2):

S＝2(2ab+bc+2ca) (2)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+d，c＝l₃+ d; wherein l₁、l₂、l₃Length, width and height of the reference body of the sound source, respectively₁Is the distance from the wall to the front end face of the reference body; measuring the distance d to be 1.0 m;

if the toilet bowl matched with the water tank provided with the water inlet valve sample to be measured is installed close to a wall corner, the position array coordinates (x, y, z) of the microphone on the parallelepiped measuring surface are (2a, -b,0.5c), (a, -2b,0.5c), (2a, -2b, c), (a, -b, c), and the area S is calculated according to the formula (3):

S＝2(2ab+bc+ca) (3)

in the formula: a is 0.5l₁+0.5d，b＝0.5l₂+0.5d，c＝l₃+ d; wherein l₁、l₂、l₃Are respectively sound sourcesLength, width and height of reference body, length l of reference body₁And width l₂I.e. the distance from the two walls to the opposite side of the respective reference body; the measurement distance d is 1.0 m.

4. The method of claim 1, wherein the sound pressure level measurement is performed by the steps of:

(1) except 1 test water tank for assembling a water inlet valve sample to be tested, a supporting rack thereof and a tripod experimental apparatus, all other articles in the test chamber are removed, and no redundant personnel can be present in the test chamber; the experimental operator must not wear clothing with significant sound absorption characteristics; measuring and recording the air temperature and the atmospheric pressure in the test chamber by using a thermometer and a barometer which are qualified by verification;

(2) before testing a sample of a water inlet valve of a toilet water tank, firstly, measuring the size l of the test water tank by using a steel ruler and a square ruler₁、l₂、l₃And recording; according to the number of reflection planes involved in the installation mode of the matched toilet, determining the space positioning of the sound source reference body and calculating the characteristic dimension d of the sound source reference body₀(ii) a Selecting an applicable parallelepiped enveloping sound source measuring surface and calculating the sizes a, b and c of the applicable parallelepiped enveloping sound source measuring surface; measuring the position array of the surface microphone according to the selected parallelepiped, calculating and recording the coordinates of the measuring points;

(3) the sound level meter used for measurement meets the requirements of a 1-type instrument in GB/T3785.1-2010, and the verification period does not exceed 2 years; the filter meets the requirement of a type 1 instrument in IEC 61260:1995, and the calibration period does not exceed 1 year; before the test is started and after the test is finished, verifying the test on one or more frequencies in the measuring frequency range of the sound level meter by using a sound calibrator meeting the requirement of the level 1 accuracy in GB/T15173; the difference of the readings is not more than 0.5 dB;

(4) the inlet noise test chamber of the inlet valve of the toilet water tank can be a semi-anechoic chamber or a reverberation chamber, so that the available space volume in the test chamber is ensured to meet the installation requirements of the test water tank and a support frame thereof, corresponding water supply/drainage conditions are provided, and the dynamic pressure of test water can be regulated and controlled; wherein, the background noise in the semi-silencing chamber is not more than A weighted 16dB, the acoustic condition of approximate free field above the reflecting surface can be provided, and the verification period is not more than 5 years; the background noise in the reverberation room is not more than 25dB of the weighting A, and the reverberation time is in the range of 5 s-6 s;

(5) in the test chamber meeting the requirements, positioning the coordinates of the measuring points according to the position array of the selected parallelepiped measuring surface microphone; simultaneously moving the tripod to a measuring point position and placing a sound level meter with related acoustic performance on a top tripod head of the tripod to ensure that the orientation of the microphone is the same as the sound wave incident angle when the microphone is calibrated and the microphone vertically points to a measuring surface;

(6) starting timing 10s after the water inlet valve is opened until the water inlet valve is naturally closed, and taking the timing as the integral time of sound level meter audio signal acquisition; if the water replenishing cycle of the sample of the water inlet valve to be detected is less than 30s, the integration time is counted by 20 s; determination of the cumulative percentage time-averaged sound pressure level L of the background noise on selected parallelepiped measuring surfaces using the slow time weighting characteristic "S" of the A-weighted equivalent sound level of the sound level meter_pAi(B)(50)Continuously measuring the position of each microphone for 3 times, taking the arithmetic mean value of the continuous measurements as a sound pressure level measurement value of background noise at the position and recording the sound pressure level measurement value; if the difference of the sound pressure levels measured 3 times at each position is greater than 0.5dB, re-measuring and recording;

(7) adjusting the dynamic pressure of the test to 0.30MPa +/-0.05 MPa, and emptying the water in the test water tank according to the water supplement requirement to be tested; timing is started 10s after water is re-fed until the water inlet valve is naturally closed, and the timing is used as the integral time for collecting the audio signal of the sound level meter; if the water replenishing cycle of the sample of the water inlet valve to be detected is less than 30s, the integration time is counted by 20 s; determining the cumulative percentage time average sound pressure level L 'of the inlet water noise of the toilet cistern inlet valve on the selected parallelepiped measuring surface by using the slow time weighting characteristic S of the A weighting equivalent sound level of the sound level meter'_pAi(ST)(50)Continuously measuring the position of each microphone for 3 times, and taking the arithmetic mean value of the positions as the sound pressure level measurement value of the water inlet noise at the position and recording the sound pressure level measurement value; if the difference of the sound pressure level measured 3 times at each position is more than 0.5dB, re-measuring; and simultaneously recording the dynamic pressure, the water supplement amount and the water supplement period of each water inflow.

5. The method for detecting the water inlet noise of the water inlet valve of the toilet tank as claimed in claim 1, wherein the result evaluation is performed according to the following steps:

(1) according to the national environmental protection standard and the standard requirements of related products, the following grading judgment standards are adopted:

the noise of water inlet is very low, and the environmental protection performance is excellent;

the noise of water inlet is low, and the environmental protection performance is good;

the water inlet noise is low, and the environmental protection performance is good;

the flushing noise is high, and the environmental protection performance is poor;

the flushing noise is very high, and the environmental protection performance is poor;

(2) when a certain sample water inlet noise A is weighted, the cumulative percentage sound power level L is calculated_WA(50)The water inflow noise A of 3 samples in the group is weighted and accumulated in percentage acoustic power level L_WA(50)Arithmetic mean value

When 10%, a group of samples need to be extracted again to repeat the experiment; calculating the slow time weighting characteristic 'S' of the A-weighted equivalent sound level of the front and the rear groups of water inlet valve samples under the given dynamic pressure by applying a sound level meterWater inflow noise A weight-counting accumulated percentage acoustic power level L measured by hexahedron measuring surface method_WA(50)Is arithmetic mean of

If a certain sample water inlet noise A is weighted and accumulated the percentage sound power level L_WA(50)The water inlet noise A of more than the two groups of 6 samples is counted and accumulated the percentage sound power level L_WA(50)Arithmetic mean value

10% of the total weight is discarded; the accumulated percentage acoustic power level L is calculated by weighting the water inlet noise A of the rest water inlet valve sample_WA(50)Is arithmetic mean of

As the water inlet noise evaluation index of the water inlet valve sample of the toilet water tank.

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