Textile moisture-dissipating rate testing device capable of controlling water supply
Technical Field
The invention relates to a universal moisture diffusion rate measuring device for textiles, and belongs to the technical field of textile performance testing.
Background
In the conventional method, researchers have used the WER method to measure the moisture evaporation rate of fabrics. The testing method comprises the following steps of dripping 30% of water of a test sample in a windless environment with the temperature of 20 +/-1 ℃ and the relative humidity of 65 +/-5% into the center of a plastic plate, covering the back of a test cloth sample on the water drops, placing the whole plastic plate and the cloth sample on an electronic balance, recording the mass change of the plastic plate and the cloth sample along with the evaporation of the water, and finally calculating the water evaporation rate of the fabric at 30min and 60min, wherein the calculation formula is WER (%) -evaporated water mass/dripped water total mass.
GB/T21655.1-2008 assessment of quick moisture absorption drying of textiles part 1: methods in the Individual combinatorial test methods. The testing steps are as follows: after the sample is placed under standard atmospheric conditions (temperature 20 +/-2 ℃ and relative humidity 65 +/-3%) and is subjected to humidity reduction and equilibrium, the sample is flatly placed on a test platform (the fabric surface close to the skin in use faces upwards), a proper amount of tertiary water is sucked by a burette, about 0.2mL of water is lightly dripped on the sample, when the water is completely diffused on the surface of the sample, the sample is immediately weighed, and then the sample is naturally and flatly hung. Weighing the mass every 5min, calculating the water evaporation amount of the sample at each weighing moment, drawing a time and evaporation amount curve, intercepting a section with a relatively straight trend in the curve, and calculating the slope of the section, namely the evaporation rate of the test sample, wherein the faster the evaporation rate is, the stronger the quick drying property of the fabric is.
However, the indexes measured by these test methods do not clearly characterize the rate of moisture release of the fabric. The moisture release rate can be defined as the amount of water released by the fabric in a unit time, unit area and constant moisture release state, and is a key indicator affecting the quick drying performance of the fabric.
Whether the WER test method or the method in the GB/T21655.1 standard is used for dosing moisture to the fabric in a dripping mode, due to the fact that the moisture cannot be continuously fed, the moisture in the fabric is continuously consumed in the test process, and therefore the moisture evaporation rate in the test process changes from block to block slowly: in the initial testing stage, the moisture content in the fabric is high, and the moisture is quickly evaporated; and in the later period of testing, the moisture is almost evaporated, the moisture content in the fabric is low, and the moisture evaporation is slow. The data thus measured is in fact the average evaporation rate of the water during the drying of the fabric. In addition, because the water supply amount is fixed, the constant of the fabric moisture dispersion area during the test cannot be ensured, because the absorption and conduction effects of different fabrics on moisture are different, the diffusion areas of the same volume of water on the surfaces of different fabrics are different, and the diffusion area of the moisture is equivalent to the moisture dispersion area of the fabric during the test. The indexes measured by the existing test method do not meet the definition of the fabric moisture release rate, so the existing test method cannot be used for representing the moisture release rate of the fabric.
In addition, the existing test method has too much manual intervention, the fabric is influenced by unstable human factors in the frequent weighing process, for example, a moving sample can generate fine air convection, moisture on the fabric can be attached to a container in the moving process of the fabric, and the like, and the factors can cause errors to the test and influence the effectiveness and the accuracy of the test.
Disclosure of Invention
The purpose of the invention is: the device for measuring the moisture evaporation rate of the fabric can continuously supply water at a constant speed, effectively control the moisture dispersion area of the fabric, ensure that the fabric is in a constant and controllable moisture dispersion state in a test and automatically record a test result.
In order to achieve the purpose, the technical scheme of the invention provides a textile moisture dissipation rate testing device for controlling water supply, which is characterized by comprising a sample rack and a buffer table, wherein the sample rack is used for bearing a sample, most of the area of the sample is positioned on the sample rack, the area of the upper surface of the sample rack, which is in contact with the sample, is a moisture dissipation area, the small area of the sample is positioned on the buffer table, the area of the upper surface of the buffer table, which is in contact with the sample, is a water absorption area, and the upper surface of the sample rack is flush with the upper surface of the buffer table;
the sample is arranged on the weighing device, and the weighing device is used for measuring the change condition of the mass of the absorbed water in the sample testing process;
the top that is located the sample on the cushion table is equipped with the apron, and the sample below the apron is aimed at behind the apron is passed to the one end opening of rubber tube, and the other end of rubber tube links to each other with the syringe pump, and the syringe pump passes through the rubber tube and supplies water to the sample constant speed, and until the sample is whole moist, the sample moisture content that the calculation obtained is A, then has:
in the formula, N is the record value of the weighing equipment when the sample reaches the equilibrium of water supply and moisture dissipation, and N is
0The 1 st recorded value of the weighing apparatus at the beginning of the test, G is the total dry weight of the sample.
Preferably, the distance between the sample holder and the buffer stage is less than 1 cm.
Preferably, the syringe pump is a micro infusion pump.
The invention discloses a textile moisture-dispersing rate testing device for controlling water supply, which can continuously supply water at a constant speed, effectively control the moisture-dispersing area of a fabric, ensure that the fabric is in a constant and controllable moisture-dispersing state in a test, and cannot influence the evaporation rate of the fabric due to the reduction of moisture in the fabric. The invention has the following beneficial effects:
1. the invention fixes the moisture dispersing area of the fabric, stabilizes the moisture dispersing state of the fabric by using continuous constant-speed water supply, can quantitatively compare the moisture dispersing rates of different fabric samples, can reveal the moisture dispersing rates of the same fabric in different moisture content states, and is helpful for researching the moisture dispersing mechanism of the textile;
2. the invention is suitable for testing the evaporation rate of most textiles, can be universally used for testing the moisture dissipation rate of various fabrics such as woven fabrics, knitted fabrics, non-woven fabrics and the like, and has higher popularization;
3. according to the invention, a one-side water supply mode is adopted, and the buffer table is used for reducing the influence of water drop tension and gravity on the weighing sensor during water injection, so that the test precision is improved; the weighing sensor is used for monitoring the mass change of a test sample, can automatically record data and feed back the moisture dispersing state of the fabric in time during testing, and has the advantages of high efficiency and small error;
4. the invention reduces the complexity and the working strength of the operation, improves the accuracy of each item of data in the test process through the automatic monitoring and recording of the data, avoids the error possibly caused by manual operation, and ensures that the device has high reproducibility and stability when testing at different time and different places.
Drawings
Fig. 1 is a schematic structural diagram of a textile moisture dissipation rate testing device for controlling water supply according to the present invention.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
The invention is realized by a textile moisture-dispersing rate testing device for controlling water supply, as shown in figure 1, and comprises an injection pump 1, a sample rack 2, a weighing inductor 3, a buffer table 4 and a cover plate 5.
The injection pump 1 is a micro-infusion pump and is used for controlling the water supply speed of the fabric sample during the test, the water supply speed is selected within the range of 0.1-600ml/h, and the precision is 0.1 ml/h. The sample holder 2 is used to hold the fabric sample, giving it a moisture-dissipating platform. The left end of the fabric sample is mostly positioned on the sample frame 2 and is a moisture dispersing area, and the right end of the fabric sample is mostly positioned on the buffer table 4 and is a water absorbing area.
The sample holder 2 and the wet-out area of the fabric sample are placed on a weighing sensor 3. The weighing sensor 3 is used for measuring the change condition of the mass of the absorbed moisture in the test process of the fabric sample and indirectly reflecting the moisture diffusion state of the fabric sample. The precision of the weighing sensor 3 is 0.001g, and data can be recorded and output regularly.
The water-absorbing area of the fabric sample is placed on the buffer table 4. The platform height of the buffer table 4 is flush with the testing platform height of the sample frame 2, the gap distance between the buffer table 4 and the testing platform is less than 1cm, the sample is ensured to be horizontally placed, and unnecessary moisture dispersing area and gravity moment generated at the gap between the buffer table 4 and the sample frame 2 are reduced to the maximum extent. The cover plate 5 is placed on the water absorption area of the fabric sample to ensure that the water absorption area of the fabric sample does not participate in moisture dissipation.
The injection pump 1 is connected with a small hole in the middle of the cover plate 5 by a rubber tube and is used for supplying water to a fabric sample at a constant speed.
The specific test steps of the invention are as follows:
step 1: the injector is filled with water and connected with the injector and the small holes on the cover plate 5 by rubber tubes, and the injector is pressed to fill the whole rubber tube with water.
Step 2: the injector is arranged on the injection pump 1, the water supply speed is set, the injection pump 1 is started, and the injection pump 1 is suspended after water can flow out from the small hole of the cover plate 5 at a constant speed.
And step 3: the fabric sample was cut to a size of 120mm by 50mm and weighed, noting that the dry weight of the fabric sample was G. The cut fabric sample was laid flat on the sample holder 2, and the right end 20mm of the fabric sample was placed on the buffer table 4, and the cover plate 5 was covered to completely cover the portion. The weighing sensor 3 is turned on, the syringe pump 1 is turned on, and the test is started.
And 4, step 4: the weighing sensor 3 records the mass data of the fabric sample every 1min and automatically draws a time-mass curve. And observing the change of the curve, and when the quality of the fabric sample does not change any more, indicating that the water supply and the moisture dissipation of the fabric sample reach an equilibrium state.
And 5: the fabric samples were observed for wetting and the test was concluded if the fabric samples were fully wetted. And if the fabric sample is not completely wetted, properly increasing the water supply speed, and repeating the operation of the step 4 again. If the quality of the fabric sample is continuously improved and the fabric sample tends to drip, the water feeding speed is properly reduced, and the operation of the step 4 is repeated again.
Step 6: and recording the water supply speed when the water supply and the moisture dispersion of the sample reach an equilibrium state, and dividing the water supply speed by the moisture dispersion area of the sample to obtain the moisture dispersion rate of the sample per unit area.
And 7: and calculating the water content A of the sample, wherein the water content A comprises the following components:
in the formula, N is the record value of the weighing equipment when the sample reaches the equilibrium of water supply and moisture dissipation, and N is
0The value recorded for the 1 st time of the weighing sensor 3 at the beginning of the test, G is the total dry weight of the sample.