Method for measuring friction force of tobacco leaves

Abstract

The invention discloses a method for measuring the friction force of tobacco leaves. The method comprises the following steps: step 1, selecting a tobacco leaf sample; 2, pretreating a tobacco leaf sample; step 3, cutting the tobacco leaf sample to prepare a to-be-measured sample; step 4, fixing a sample to be measured; step 5, setting test parameters, and determining parameters of the sliding block rubbed with the sample to be measured; and step 6, the friction force detection platform measures the friction force value with the to-be-measured sample by using the sliding block. Through the method, a tobacco leaf friction force detection result can be displayed in a quantitative form, the friction force of raw material tobacco leaves of different producing areas and grades is objectively evaluated through specific data, and scientific data support is provided for raw material conveying belt selection and equipment inclination angles of different raw material states and different working procedures in the production process; and meanwhile, adjustment of processing parameters of different raw materials is scientifically guided in the processing process, so that the phenomena of sheet running and accumulation of the raw materials are avoided, and the product uniformity is improved.

Description

Technical Field

[0001] The invention relates to the technical field of tobacco leaf quality measurement, and in particular to a method for measuring tobacco leaf friction using a texture analyzer. Background Art

[0002] The texture analyzer tests samples by simulating human touch. Its results are highly sensitive and objective, thus avoiding the subjective influence of human factors on the quality evaluation results of items. It is an instrument that can accurately, quickly and effectively perform quantitative testing. It is now widely used in food, horticulture, animal husbandry, aquatic products, forestry, agriculture, cosmetics, chemicals, medicine and other fields.

[0003] During the tobacco leaf processing, especially in the leaf threshing, re-roasting and silk-making stages, the tobacco leaves need to be placed on a conveyor belt and transported to the next stage for production and processing. However, due to differences in friction between raw materials of different origins and grades, some raw materials will experience "sheet runaway", especially during the raw material mixing process. This phenomenon will cause uneven mixing of the raw materials, directly affecting the quality of cigarettes.

[0004] In the traditional production process, the selection of transmission belt types and inclination angles mostly rely on experience. Once the equipment is fixed, it is difficult to change. The "sheet runaway" phenomenon is also difficult to obtain effective scientific data support in the early design process, which has a great impact on production. To address this phenomenon, the only way is to passively adjust the production and processing parameters to reduce the belt running speed or adjust the moisture content of the raw materials to increase the friction between the raw materials and the raw materials and the belt, which seriously affects the production efficiency and the quality of the final product.

[0005] At present, the softness of tobacco leaves is generally measured by using a texture analyzer. For example, the public document with the announcement number CN117538151A, the publication date of February 9, 2024, and the patent name "A method for measuring the softness of tobacco leaves based on a double-slit structure using a texture analyzer" discloses a method for measuring the softness of tobacco leaves based on a double-slit structure using a texture analyzer, which involves the technical field of tobacco quality measurement. The following steps are included: S1: Prepare an auxiliary platform and set up two slit structures; S2: Fix the platform on the texture analyzer detection platform; S3: Measure the length of the tobacco leaves and mark 2-5 equal parts; S4: Balance the moisture in the tobacco leaves; S5: Divide into two pieces with the main vein as the dividing line; S6: Place the sample between the two slit structures and cover with a buckle plate; S7: Set the texture analyzer parameters; S8: The test probe presses down on the sample and records the maximum stress; S9: Detect the maximum stress at each equal point and calculate the average value;

[0006] S10: Repeat operations S3, S5, S6, S8 and S9 for different samples of the batch, remove the maximum and minimum values, and calculate the average value, which is the softness of this batch of tobacco leaves, and determine its stability.

[0007] In view of the above reasons and existing equipment, there is a need for a method that can measure the friction of tobacco leaves based on a texture analyzer to objectively evaluate the friction of tobacco leaves, thereby scientifically guiding the early equipment selection, installation and processing parameter setting during the production process. Summary of the invention

[0008] The technical problem to be solved by the present invention is to realize a method for detecting the friction force of tobacco leaves by using a texture analyzer. Through this method, the detection results of the friction force of tobacco leaves can be presented in a quantitative form, and the friction force of raw tobacco leaves of different origins and grades can be objectively evaluated with specific data, so as to provide scientific data support for the selection of raw material transport belts and equipment inclination angles for different raw material states and different processes in the production process, and at the same time, scientific guidance can be provided for the adjustment of processing parameters of different raw materials during the processing process to avoid the phenomenon of "sheet running" and accumulation of raw materials and improve product uniformity.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is: a method for measuring the friction force of tobacco leaves, comprising the following steps:

[0010] Step 1, selecting tobacco leaf samples;

[0011] Step 2, pre-treating tobacco leaf samples;

[0012] Step 3, cutting tobacco leaf samples to prepare samples to be measured;

[0013] Step 4, fixing the sample to be measured;

[0014] Step 5: Test parameter setting, determining the parameters of the slider that rubs against the sample to be measured;

[0015] Step 6: The friction force detection platform uses a slider to measure the friction value of the sample to be measured.

[0016] In the step 1, a tobacco leaf sample with intact leaves and no obvious dust or spots on the leaf surface is selected for testing.

[0017] In step 2, the sample to be tested should be placed in a constant temperature and humidity chamber for moisture balance.

[0018] The parameters of the water balance are set as follows: balance for more than 48 hours, and the balance conditions are: temperature 22±2° C., humidity 70±2%.

[0019] In step 3, the tobacco leaves are laid flat and the tobacco stems are removed, and then two rectangular samples of the same size are cut from the left and right sides of the tobacco leaves as samples to be tested, one for testing the front friction and the other for testing the back friction.

[0020] In the step 4, the sample to be measured is laid flatly on the friction force detection platform, and two short sides are fixed with a clamping tool.

[0021] In step 5, a slider having a contact surface size smaller than that of the sample to be measured is selected, the slider weight is 200±50g, the pulling force is set to 100.0±30g, the trigger force is 5.0±1.0g, the pre-test speed is 1.00±0.2mm / s, the test speed is 2.5±0.5mm / s, the moving distance is 50±10mm, and the surface of the slider in contact with the sample to be measured is covered with felt material.

[0022] In step 6, the data are obtained by reciprocating multiple times each time to obtain the average value of the data as the front friction force and the back friction force of the batch of tobacco leaf samples.

[0023] The friction force detection platform is an SMS TA XTplusC texture analyzer, and the model is A / FR.

[0024] The present invention has the following beneficial effects:

[0025] 1. Fix the sample on the detection platform of the texture analyzer through the auxiliary platform, use the test probe of the texture analyzer to set its parameters to move the slider, and characterize the friction of the tobacco leaf by recording the friction between the slider and the tobacco leaf plane. Creatively test the front and back surfaces, and quantitatively characterize the friction of different raw materials by taking the average value.

[0026] 2. The test results have good accuracy, sensitivity and objectivity. For the first time, friction is introduced into the test index, and the processing parameters are reasonably adjusted according to the friction to better promote the homogenization production of raw materials.

[0027] 3. The texture analyzer is used to simulate human touch to analyze and detect samples, which overcomes the current situation where the selection of materials, shapes and inclination angles of traditional transport belts mainly relies on manual experience, and provides scientific data to guide the early equipment installation. This method is simple to operate, is not subject to human interference, has high detection sensitivity, good reproducibility, and uses quantitative indicators to objectively and comprehensively evaluate the friction performance of tobacco leaves, which can better serve cigarette companies. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The following is a brief description of the contents expressed in each figure in the specification of the present invention:

[0029] Figure 1 Make a schematic for the friction force sample. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the specific implementation methods of the present invention, such as the shape, structure, relative position and connection relationship between the various components involved, the function and working principle of each part, the manufacturing process and operation method, etc., through the description of the embodiments with reference to the accompanying drawings, so as to help those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0031] The method for detecting the friction force of tobacco leaves using a texture analyzer comprises the following steps:

[0032] Step 1: Selection of tobacco leaf samples: Select tobacco leaf samples with complete leaves, no obvious dust and no spots on the leaf surface for testing;

[0033] Step 2: Sample pretreatment: The sample to be tested should be placed in a constant temperature and humidity chamber for moisture balance. Preferably, the balance should be for more than 48 hours. The balance conditions are: temperature 22±2℃, humidity 70±2%;

[0034] Step 3: Sample preparation: Lay the tobacco leaves flat on the table, use a paper cutter or other equipment to remove the stems, so that the leaves are symmetrically divided into two parts, and then select the middle position to cut into 100mm*250mm rectangular samples longitudinally, and store them on the left and right sides respectively, one for testing the front friction and the other for testing the back friction. Each sample is tested only once;

[0035] Step 4: Sample fixation: Place the prepared sample flatly on the friction force testing platform and fix the two short sides with a clamping tool;

[0036] Step 5: Test parameter setting: select a slider with a size of 62mm*62mm and a weight of 200g for friction test, set the pulling force to 100.0g, the trigger force to 5.0g, the pre-test speed to 1.00mm / s, the test speed to 2.5mm / s, the moving distance to 50mm, and select different materials to adhere to the lower surface of the slider as needed, preferably choose felt material, cut it to the same size as the lower surface of the slider and stick it to the lower surface of the slider;

[0037] Step 6: Friction force determination and result expression: Start the device and record the magnitude of dynamic friction force; continuously test the front and back friction forces of the samples 10 times each, and take the average value as the friction force of the batch of samples.

[0038] The specific test process is listed below: select three single-grade tobacco samples of C2F produced in Fujian, Henan and Sichuan in 2022, and measure the friction of the three tobacco samples by texture analyzer, which specifically includes the following steps:

[0039] Step 1: Selection of tobacco leaf samples: 10 tobacco leaf samples with complete leaves, no obvious dust and no spots on the leaf surface from three single-grade tobacco leaf samples produced in Fujian, Henan and Sichuan in 2022 were selected for testing;

[0040] Step 2: Sample pretreatment: The sample to be tested should be placed in a constant temperature and humidity chamber for moisture balance. Preferably, the balance should be for more than 48 hours. The balance conditions are: temperature 22±2℃, humidity 70±2%;

[0041] Step 3: Sample preparation: Lay the tobacco leaves flat on the table, use a paper cutter or other equipment to remove the stems, so that the leaves are symmetrically divided into two parts, and then select the middle position to cut into 100mm*250mm rectangular samples longitudinally, and store them on the left and right sides respectively, one for testing the front friction and the other for testing the back friction. Each sample is tested only once;

[0042] Step 4: Sample fixation: Place the prepared sample flatly on the friction force testing platform and fix the two short sides with a clamping tool;

[0043] Step 5: Test parameter setting: select a slider with a size of 62mm*62mm and a weight of 200g for friction test, set the pulling force to 100.0g, the trigger force to 5.0g, the pre-test speed to 1.00mm / s, the test speed to 2.5mm / s, the moving distance to 50mm, and select different materials to adhere to the lower surface of the slider as needed, preferably choose felt material, cut it to the same size as the lower surface of the slider and stick it to the lower surface of the slider;

[0044] Step 6: Determination of friction and expression of results: Start the device and record the magnitude of friction; continuously test the front and back friction of the sample 10 times each, and take the average value as the friction of the batch of samples.

[0045] Specifically, the texture analyzer selected is SMS TA XTplusC texture analyzer, and the test platform is friction detection platform, whose model is A / FR model. The friction of tobacco leaves is measured, and the dynamic friction between the slider and the tobacco leaf surface is recorded as the sample friction.

[0046] Specifically, the same batch of tobacco leaves in step 1 are tobacco leaves of the same grade, origin, grade and year. For the above-mentioned same batch of tobacco leaves, different tobacco leaf samples need to be selected for testing for no less than 10 times, which can increase the number of test samples and improve the accuracy of the measured friction data. In this embodiment, different tobacco leaves of the same grade, origin, variety and year are selected to repeat the test 10 times, and the dynamic friction data of each time are recorded, so as to obtain the friction of 10 samples. Due to the different sunlight exposure during the growth of tobacco leaves, the structural differences between the front and back sides will be formed. Generally speaking, the front side of tobacco leaves has more chlorophyll content, stronger photosynthesis, thicker mesophyll tissue, and is also easier to secrete oil, so the surface is relatively smooth, while the back side has less chlorophyll accumulation, lighter color, thinner mesophyll tissue, prominent veins, and relatively rough, resulting in a certain difference in friction between the front and back sides. In order to ensure the authenticity and reliability of the data, the friction force of the front and back sides is detected respectively, and recorded separately.

[0047] Specifically, the step of examining the stability of the friction force of the sample to be tested in the above step S10 is: calculating its coefficient of variation value based on the friction force data, and the calculation method is: coefficient of variation value = standard deviation / average value, and determining the stability of the measured tobacco leaf friction force by the coefficient of variation value.

[0048] According to the set texture analyzer parameters, the specific test data of friction force measured in Fujian, Henan and Sichuan are shown in Table 1 below:

[0049]

[0050] Note: C2F is the tobacco grade, which is the middle orange-yellow second-grade tobacco.

[0051] Table 1

[0052] From Table 1, we can see that the friction of raw materials from different origins is different, and the friction of the front and back of tobacco leaves from the same origin is also different: the difference in friction between the front and back of raw materials from Fujian is relatively large, while the difference in friction between the front and back of raw materials from Sichuan and Henan is relatively small; in general, the friction in Sichuan is relatively small, and the comprehensive friction in Fujian and Henan is relatively close. By testing the friction of tobacco leaf samples, the friction test results of tobacco leaves are objectively presented in a quantitative form, providing scientific data support for the selection of raw material transport belts and equipment inclination angles for different raw material states and different processes in the production process. At the same time, scientific guidance is provided during the processing process to adjust the processing parameters of raw materials from different origins to avoid the phenomenon of "sheet running" and accumulation of raw materials and improve product uniformity.

[0053] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A method for measuring the friction force of tobacco leaves, characterized in that: The following steps are involved: Step 1, selecting tobacco leaf samples; Step 2, pre-treating tobacco leaf samples; Step 3, cutting tobacco leaf samples to prepare samples to be measured; Step 4, fixing the sample to be measured; Step 5: Test parameter setting, determining the parameters of the slider that rubs against the sample to be measured; Step 6: The friction force detection platform uses a slider to measure the friction value of the sample to be measured.

2. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In the step 1, a tobacco leaf sample with intact leaves and no obvious dust or spots on the leaf surface is selected for testing.

3. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In step 2, the sample to be tested should be placed in a constant temperature and humidity chamber for moisture balance.

4. The method for measuring the friction force of tobacco leaves according to claim 3, characterized in that: The parameters of the water balance are set as follows: balance for more than 48 hours, and the balance conditions are: temperature 22±2° C., humidity 70±2%.

5. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In step 3, the tobacco leaves are laid flat and the tobacco stems are removed, and then two rectangular samples of the same size are cut from the left and right sides of the tobacco leaves as samples to be tested, one for testing the front friction and the other for testing the back friction.

6. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In the step 4, the sample to be measured is evenly laid on the friction force detection platform, and two short sides are fixed with a clamping tool.

7. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In step 5, a slider having a contact surface size smaller than that of the sample to be measured is selected, the slider weight is 200±50g, the pulling force is set to 100.0±30g, the trigger force is 5.0±1.0g, the pre-test speed is 1.00±0.2mm / s, the test speed is 2.5±0.5mm / s, the moving distance is 50±10mm, and the surface of the slider in contact with the sample to be measured is covered with felt material.

8. The method for measuring the friction force of tobacco leaves according to claim 1, characterized in that: In step 6, the data are obtained by reciprocating multiple times each time to obtain the average value of the data as the front friction force and the back friction force of the batch of tobacco leaf samples.

9. The method for measuring the friction force of tobacco leaves according to claim 8, characterized in that: The friction force detection platform is an SMS TA XTplusC texture analyzer, and the model is A / FR.

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