CN104849208A - Fiber friction coefficient testing device and testing method thereof - Google Patents

Abstract

The invention relates to a fiber friction coefficient testing device and a testing method thereof. The test device includes a friction roller, a hook, a first tension clamp, a second tension clamp, a first stepping motor, a force sensor, an amplifier, a first pulse distributor, a computer and its input and output devices. Through the above structure, the friction roller can be rotated to test fiber friction. The testing device may further include a second stepping motor, a first gear, a synchronous gear belt, a second gear, a screw mandrel, a screw block, an upper limiter, a lower limiter, and a second pulse distributor. This additional structure can also be used to perform friction roller lift test fiber friction. The device and method of the invention have the advantages of high testing accuracy and high testing efficiency, and can display the fluctuation curve of friction force in real time, and automatically analyze the friction coefficient of fibers and the variation of friction force during the test process.

Description

A fiber friction coefficient testing device and testing method thereof

technical field

The invention belongs to the field of fiber material measuring instruments, in particular to a fiber friction coefficient testing device and a testing method thereof.

Background technique

The fiber friction coefficient refers to the ratio of the friction force between two contact surfaces to the vertical force acting on one surface, which is related to the roughness of the fiber surface and has nothing to do with the size of the contact area. Fiber friction coefficient is closely related to textile production and yarn properties. In the process of fiber spinning, in some cases, it is necessary to increase the friction between fibers, such as roller pressure, yarn twisting, etc.; in other cases, it is necessary to reduce the friction between fibers, such as chemical fiber oiling agent, fiber Channel clean, etc. Fiber friction properties will also affect the hand feeling, pilling, wear resistance and wrinkle resistance of its finished products. Therefore, it is of great significance to study the fiber friction coefficient test device and its test method.

The current fiber friction coefficient test method mostly adopts the Roeder method. The principle is to surround the fiber at a certain angle on the friction roller, and apply equal tension to both ends of the fiber. When reducing the tension at one end of the fiber or rotating the friction roller, the fiber will There is friction with the surface of the friction roller, and the tension at one end of the fiber will become smaller. The tension change is measured by means of a force measuring device, and the fiber friction coefficient is calculated according to Euler's formula. The instrument that uses this principle to test the fiber friction coefficient is represented by the Y151 fiber friction coefficient tester, which is mainly characterized by a single capacitor running asynchronous motor and a gear box to drive the friction roller to rotate, and using a torque balance as a force measuring device. The instrument can only set 8 speeds of the friction roller rotation speed through the gear box, and cannot provide more rotation speeds to study the influence of the friction roller rotation speed on the fiber friction coefficient. The force measuring device of this instrument uses a torque balance, which has a low force value resolution (0.5×10 ^-3 cN) and a small force value measurement range (250×10 ^-3 cN). Turning the torque balance handle and manual visual reading may cause Operation errors, and require a high degree of operator proficiency. Therefore, according to the test requirements of the fiber friction coefficient, there is an urgent need for an electronic fiber friction coefficient tester, which has high force value accuracy, large measuring range, and a fiber friction coefficient tester that can be accurately adjusted by inputting the frequency of the stepping motor. To improve the accuracy of test results and test efficiency.

Contents of the invention

The object of the present invention is to provide a fiber friction coefficient testing device and its testing method, which mainly solve the problems existing in the above-mentioned prior art. The fiber friction coefficient and the variation of friction force during the test process.

To achieve the above object, the present invention is achieved in this way.

A fiber friction coefficient testing device is characterized in that it includes a friction roller, a hook, a first tension clamp, a second tension clamp, a first stepping motor, a force sensor, an amplifier, a first pulse distributor, a computer and its input Output device; wherein: the friction roller is hung with a sample at an enveloping angle; the first tension clamp clamps one end of the sample, and the first tension clamp is connected to the force sensor through a hook; the force value resolution of the force sensor Below 0.25×10 ^-3 cN, the measuring range of the force value is above 1000×10 ^-3 cN; the force sensor is further connected to the computer through the amplifier; the second tension clamp clamps the other end of the sample and allows the second tension clamp to hang freely on the The other side of the friction roller; the friction roller is driven and rotated by the first stepping motor controlled by the computer through the first pulse distributor.

The described fiber friction coefficient testing device is characterized in that: the device further includes a second stepping motor, a first gear, a synchronous gear belt, a second gear, a screw mandrel, a screw block, an upper limiter, a lower limiter, a second Two-pulse distributor; wherein: the screw rod is set upright and a screw block is set on the screw rod, and the screw block is connected to the friction roller; one end of the screw rod is connected to the transmission structure composed of the first gear, the synchronous gear belt and the second gear, The transmission structure is connected and driven by a second stepper motor controlled by a computer through a second pulse distributor; the upper and lower movable paths of the screw block respectively have an upper limiter and a lower limiter.

The device for testing fiber friction coefficient is characterized in that: the input and output devices are displays and/or printers.

A fiber friction coefficient test method is characterized in that: it adopts the test device as described above, and the specific steps include:

A The first tension clamp and the second tension clamp clamp the two ends of the sample, and then hang the sample on the friction roller, the first tension clamp is hung on the hook, and the second tension clamp is freely hung on the other side of the friction roller. When , the two ends of the sample riding on the friction roller are subjected to the same tension;

B Conduct friction roller rotation test fiber friction:

The computer drives the first stepping motor through the first pulse distributor to drive the friction roller to rotate. Due to the friction effect, the friction roller drives the sample to move on the surface of the friction roller, and the weight of the first tension clamp is slowly loaded on the hook. The load signal of the force sensor and the amplifier will display the load-time curve in real time on the output device, and the friction roller will stop rotating after the set time;

C The computer automatically analyzes the load-time curve to obtain the friction force of the fiber sample, and calculates the fiber friction coefficient according to Euler's formula.

A fiber friction coefficient test method is characterized in that: it adopts the test device as described above, and the specific steps include:

A The first tension clamp and the second tension clamp clamp the two ends of the sample, and then hang the sample on the friction roller, the first tension clamp is hung on the hook, and the second tension clamp is freely hung on the other side of the friction roller. When , the two ends of the sample hanging on the friction roller are subjected to the same tension;

B1 conduct friction roller lifting test fiber friction:

The computer drives the second stepping motor to rotate through the second pulse distributor, and drives the friction roller to descend from the upper limiter through the first gear, synchronous gear belt, second gear, screw rod and screw block, and the weight of the first tension clamp is slow The computer receives the load signal from the force sensor and amplifier connected to the hook, and displays the load-time curve on the output device in real time. After the set time or reaches the lower limiter position, the friction roller stops falling and rise to the initial position;

C The computer automatically analyzes the load-time curve to obtain the friction force of the fiber sample, and calculates the fiber friction coefficient according to Euler's formula.

Compared with prior art, the advantages of the present invention are as follows:

1. In the device of the present invention, a high-sensitivity force sensor is used to replace the force measurement method of the traditional mechanical ^{torsion balance} . The value resolution is 0.5×10 ^-3 cN, and the force value measurement range is 250×10 ^-3 cN. The force measurement accuracy and measuring range of the device of the present invention are significantly improved, which is especially important for the accuracy of fiber friction small force value measurement. The instrument uses a high-precision force sensor to avoid operational errors that may be caused by turning the torque balance handle of the old instrument and manual visual readings.

2. There are two options for fiber friction measurement of the device of the present invention, including friction roller rotation test fiber friction and friction roller lift test fiber friction, which can be selected and set according to the needs of research work.

3. The device of the present invention can display in real time the frictional force variation curve during the measurement process, and can store the test results in a computer, which is convenient for comparative analysis and research on the friction properties of various new fiber materials.

4. The rotational speed of the friction roller of the device of the present invention can be accurately adjusted by inputting the frequency of the stepping motor, which is beneficial to the research on the influence of the rotational speed of the friction roller on the fiber friction coefficient.

5. The device of the present invention can be used to test the friction coefficient of fibers of two different lengths, wool type and cotton type, while it is difficult for the old type instrument to test the friction coefficient of 38mm cotton type short fiber.

Description of drawings

Fig. 1 is a schematic structural view of a preferred embodiment of the fiber friction coefficient testing device of the present invention.

In Figure 1, 1—sample, 2—friction roller, 3—hook, 4—first tension clamp, 5—second tension clamp, 6—first stepping motor, 7—force sensor, 8—amplifier, 9 - the first stepping motor, 10 - the first gear, 11 - synchronous gear belt, 12 - the second gear, 13 - screw mandrel, 14 - screw block, 15 - upper limiter, 16 - lower limiter, 17 - the first A pulse distributor, 18-the second pulse distributor, 19-computer, 20-monitor, 21-printer.

Fig. 2 is a three-dimensional schematic view of the device box and the operation panel of the present invention.

In Fig. 2, 22—box body, 221—upper chassis, 2211—plexiglass door, 222—lower chassis, 2221—potentiometer, 2222—reset button, 2223—test button, 2224—down button, 2225—stop button, 2226—up button, 2227—power switch.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Please refer to FIG. 1 , which is a schematic structural diagram of a preferred embodiment of a fiber friction coefficient testing device of the present invention. As shown in the figure: it includes friction roller 2, hook 3, first tension clamp 4, second tension clamp 5, first stepper motor 6, force sensor 7, amplifier 8, first pulse distributor 17, computer 19 and Its input and output equipment; wherein: the friction roller 2 is hung with a sample 1 with a wrapping angle; the first tension clamp 4 clamps one end of the sample 1, and the first tension clamp 4 is connected to the force sensor 7 through the hook 3 ; The force value resolution of the force sensor 7 is less than 0.25×10 ^-3 cN, and the force value measurement range is above 1000×10 ^-3 cN; the force sensor 7 is further connected to the computer 19 through the amplifier 8 ; the second tension clamp 4 clamps Hold the other end of the sample 1 and hang the second tension clamp 4 freely on the other side of the friction roller 2; The input and output devices are a display 20 and/or a printer 21 .

Using the above-mentioned test device, the specific steps include:

A The first tension clamp 4 and the second tension clamp 5 clamp both ends of the sample 1, and then hang the sample 1 on the friction roller 2, the first tension clamp 4 is hung on the hook 3, and the second tension clamp 5 is free Hang on the other side of the friction roller 2, at this time, the two ends of the sample 1 riding on the friction roller 2 are subjected to the same tension;

B. Carry out friction roller rotation test fiber friction (standing test items):

The computer 19 drives the first stepper motor 6 through the first pulse distributor 17 to drive the friction roller 2 to rotate. Due to the friction effect, the friction roller 2 drives the sample 1 to move on the surface of the friction roller, and the weight of the first tension clamp 4 is slowly loaded onto the hook 3 On, the computer 19 receives the load signal from the force sensor 7 and the amplifier 8 connected to the hook 3, and displays the load-time curve in real time on the output device. After the set time, the friction roller 2 stops rotating;

The C computer 19 automatically analyzes the load-time curve to obtain the friction force of the fiber sample 1, and calculates the fiber friction coefficient according to Euler's formula.

Euler's formula looks like this:

$\frac{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; \&mu;\&theta;</span>}}$

In the formula: f ₀ and f ₁ are the tensions on the two ends of the fiber hanging on the friction roller, f ₀ is equal to the tension clamp 5 load; μ is the friction coefficient between the fiber and the surface of the friction roller; θ is the friction between the fiber and the surface of the friction roller Contact angle (in radians); e is a natural constant. f ₁ is equal to the difference between f ₀ and f ₂ , where f ₂ is the load measured by the force measuring device.

When the contact angle θ between the fiber and the surface of the friction roller is equal to π, the fiber friction coefficient μ is:

$\mathrm{<span\; class="notranslate">\; \&mu;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;lge</span>}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; lg</span>}\frac{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0.732936</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; lg</span>}\frac{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0.732936</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; lg</span>}\frac{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

Please refer to Fig. 1 further, as a preferred embodiment, the device can further include a second stepper motor 9, a first gear 10, a synchronous gear belt 11, a second gear 12, a screw mandrel 13, a screw block 14, and an upper limiter 15 , the lower limiter 16, the second pulse distributor 18; wherein: the screw mandrel 13 is erected and a screw block 14 is set on the screw mandrel 13, and the screw block 14 is connected to the friction roller 2; one end of the screw mandrel 13 is connected by the first Gear 10, synchronous gear belt 11, the transmission structure that the second gear 12 forms, this transmission structure is connected and driven by the second stepper motor 9 controlled by the second pulse distributor 18 by the computer 19; It has an upper limiter 15 and a lower limiter 16 .

As above-mentioned test device, concrete steps comprise:

A The first tension clamp 4 and the second tension clamp 5 clamp both ends of the sample 1, and then hang the sample 1 on the friction roller 2, the first tension clamp 4 is hung on the hook 3, and the second tension clamp 5 is free Hang on the other side of the friction roller 2, at this time, the two ends of the sample 1 riding on the friction roller 2 are subjected to the same tension;

B Conduct friction roller rotation test fiber friction

The computer 19 drives the first stepper motor 6 through the first pulse distributor 17 to drive the friction roller 2 to rotate. Due to the friction effect, the friction roller 2 drives the sample 1 to move on the surface of the friction roller, and the weight of the first tension clamp 4 is slowly loaded onto the hook 3 On, the computer 19 receives the load signal from the force sensor 7 and the amplifier 8 connected to the hook 3, and displays the load-time curve in real time on the output device. After the set time, the friction roller 2 stops rotating;

The C computer 19 automatically analyzes the load-time curve to obtain the friction force of the fiber sample 1, and calculates the fiber friction coefficient according to Euler's formula.

B1 conduct friction roller lifting test fiber friction (optional test item):

The computer 19 drives the second stepper motor 9 to rotate through the second pulse distributor 18, drives the friction roller 2 from the upper limiter 15 through the first gear 10, the synchronous gear belt 11, the second gear 12, the screw mandrel 13, and the screw block 14. The weight of the first tension clamp 4 is slowly loaded onto the hook 3, and the computer 19 receives the load signal from the force sensor 7 and the amplifier 8 connected to the hook, and displays the load-time curve in real time on the output device. After a certain time or reaching the position of the lower limiter 16, the friction roller 2 stops descending and rises to the initial position;

The C computer 19 automatically analyzes the load-time curve to obtain the friction force of the fiber sample 1, and calculates the fiber friction coefficient according to Euler's formula.

Fig. 2 is the box body and the operation panel of the device of the present invention, and its function is to facilitate the control test, protect the electrical components in the device and ensure the test environment.

In summary, the above are only preferred embodiments of the present invention, and are not intended to limit the implementation scope of the present invention. That is, all equivalent changes and modifications made according to the content of the patent scope of the present invention shall be within the technical scope of the present invention.

Claims (5)

1. A fiber friction coefficient testing device is characterized in that: it comprises friction roller (2), hook (3), the first tension clip (4), the second tension clip (5), the first stepper motor (6 ), a force sensor (7), an amplifier (8), a first pulse distributor (17), a computer (19) and its input and output equipment; wherein: the friction roller (2) is hung with a sample ( 1); the first tension clamp (4) clamps one end of the sample (1), and the first tension clamp (4) is connected with the force sensor (7) by a hook (3); the force of the force sensor (7) The value resolution is less than 0.25×10 ^-3 cN, and the force value measurement range is more than 1000×10 ^-3 cN; the force sensor (7) is further connected to the computer (19) through the amplifier (8); the second tension clamp (4) Clamp the other end of the sample (1) and hang the second tension clamp (4) freely on the other side of the friction roller (2); the friction roller (2) is controlled by the computer (19) through the first pulse distributor (17) The first stepper motor (6) drives the rotation. 2. fiber friction coefficient testing device according to claim 1, is characterized in that: the device further comprises a second stepping motor (9), a first gear (10), a synchronous gear belt (11), a second gear ( 12), screw mandrel (13), screw block (14), upper limiter (15), lower limiter (16), second pulse distributor (18); Wherein: this screw mandrel (13) is set upright and in Screw block (14) is set on the screw mandrel (13), and this screw block (14) connects friction roller (2); The transmission structure that two gears (12) are formed, this transmission structure is connected and driven by the second stepper motor (9) controlled by the second pulse distributor (18) by the computer (19); the up and down movement path of the screw block (14) There are upper limiter (15) and lower limiter (16) respectively. 3. The fiber friction coefficient testing device according to claim 1 or 2, characterized in that: the input and output device is a display (20) and/or a printer (21). 4. A fiber friction coefficient test method is characterized in that: it adopts the test device as claimed in claim 1, and the concrete steps comprise: A The first tension clamp (4) and the second tension clamp (5) clamp the two ends of the sample (1), and then hang the sample (1) on the friction roller (2), the first tension clamp (4) Hang on the hook (3), the second tension clamp (5) hangs freely on the other side of the friction roller (2), at this time, the two ends of the sample (1) riding on the friction roller (2) are subjected to the same tension ; B Conduct friction roller rotation test fiber friction: The computer (19) drives the first stepping motor (6) through the first pulse distributor (17) to drive the friction roller (2) to rotate, and the friction roller (2) drives the sample (1) to move on the surface of the friction roller due to friction, The weight of the first tension clamp (4) is slowly loaded on the hook (3), and the computer (19) receives the load signal of the force sensor (7) and the amplifier (8) connected to the hook (3), and the output device is real-time Display load-time curve, after the set time, the friction roller (2) stops rotating; The C computer (19) automatically analyzes the load-time curve to obtain the friction force of the fiber sample (1), and calculates the fiber friction coefficient according to Euler's formula. 5. A fiber friction coefficient test method is characterized in that: it adopts the test device as claimed in claim 2, and the concrete steps comprise: A The first tension clamp (4) and the second tension clamp (5) clamp the two ends of the sample (1), and then hang the sample (1) on the friction roller (2), the first tension clamp (4) Hang on the hook (3), the second tension clamp (5) hangs freely on the other side of the friction roller (2), at this time, the two ends of the sample (1) riding on the friction roller (2) are subjected to the same tension ; B1 conduct friction roller lifting test fiber friction: The computer (19) drives the second stepping motor (9) to rotate through the second pulse distributor (18), through the first gear (10), the synchronous gear belt (11), the second gear (12), the screw mandrel (13 ), the screw block (14) drives the friction roller (2) to begin to descend from the upper limiter (15), and the weight of the first tension clip (4) is slowly loaded on the hook (3), and the computer (19) receives the The load signal of the connected force sensor (7) and amplifier (8) displays the load-time curve in real time on the output device, and the friction roller (2) stops falling after the set time or the position of the lower limiter (16) is reached and rise to the initial position; The C computer (19) automatically analyzes the load-time curve to obtain the friction force of the fiber sample (1), and calculates the fiber friction coefficient according to Euler's formula.