KR101665679B1 - A Conductive Velcro Manufacturing Method and Apparatus Thereof Comprising of Carbon Nanotube to Reduce the Electrical Resistance - Google Patents

Abstract

The method of manufacturing conductive velcro comprising carbon nanotubes according to an embodiment of the present invention includes: a step of mixing carbon nanotubes in a solvent and ultrasonic dispersion; Providing a conductive velcro having a hook and loop surface of conductive velcro positioned thereon; And a spraying step of spraying the carbon nanotube spray liquid onto the hook and loop surfaces of the conductive velcro.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method and apparatus for manufacturing a conductive velcro including a carbon nanotube for reducing electrical contact resistance,

The present invention relates to a method and apparatus for manufacturing conductive velcro comprising carbon nanotubes.

Velcro is made up of two pieces of nylon fiber, one side of which is hooked and the other side of which is a circular loop that can be bonded, detached and re-bonded. Due to the convenience of such use, it is used as various types of bonding materials. In particular, the conductive Velcro has been greatly increased in recent years.

Recently, with increasing interest in smart clothing, many researchers are paying attention to the possibility of fiber as an electrical connector. Velcro is already widely used in clothing. Therefore, conductive velcro is used as an electric connector because of its advantage that smart clothing can be easily applied without a psychological barriers to entry.

In all types of electrical connectors, a very large electrical contact resistance is generated due to the micro contact surface that occurs at the time of bonding, which causes problems such as heat generation and short circuit at the junction. Conductive Velcro is also not free from this problem. A very large electrical contact resistance is generated due to the micro contact surface that occurs during the bonding of the velcro, which causes problems such as heat generation and short circuit at the joint portion.

Particularly, in order to expand the application of the conductive velcro bonding system to the automobile and transportation field, the inventors of the present invention have found that in the previous research, the bonding characteristics for the low frequency vibration, the corresponding fretting phenomenon and the frequency ), Electrical load, and amplitude, and analyzed the influence of the change in electrical contact resistance. Conductive Velcro was found to increase the electrical contact resistance at a certain frequency, which is thought to be caused by the abrasion of the contact surface. Also, it was found that the electric contact resistance value greatly changes at a specific current, and the contact area is changed. Therefore, there is a problem that the electric contact resistance of the conductive Velcro is greatly increased under certain circumstances.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to reduce the electrical contact resistance occurring on the contact surface of the conductive Velcro by coating the carbon nanotubes on the hook and loop surfaces of the conductive Velcro.

The method of manufacturing conductive velcro comprising carbon nanotubes according to an embodiment of the present invention includes: a step of mixing carbon nanotubes in a solvent and ultrasonic dispersion; Providing a conductive velcro having a hook and loop surface of conductive velcro positioned thereon; And a spraying step of spraying the carbon nanotube spray liquid onto the hook and loop surfaces of the conductive velcro.

The solvent may be an organic solvent, and more preferably, acetone.

In the step of injecting the carbon nanotubes, 2 to 4 g of carbon nanotubes are mixed in a ratio of 140 to 160 ml of solvent, and ultrasonic dispersion treatment is performed for 110 to 130 minutes.

In addition, it is preferable that the carbon nanotubes are injected so that the fraction of the carbon nanotubes occupies 28.5% or more on the two-dimensional plane of the surface on which the conductive Velcro is formed in the dispersion step.

According to an embodiment of the present invention, there is provided a conductive Velcro including carbon nanotubes, comprising: mixing a carbon nanotube with a solvent and ultrasonic dispersion; Providing a conductive velcro having a hook and loop surface of conductive velcro positioned thereon; And a spraying step of spraying the carbon nanotube spray liquid onto the hook and loop surfaces of the conductive velcro.

The apparatus for manufacturing conductive velcro including carbon nanotubes according to an embodiment of the present invention includes a carbon nanotube injection liquid storage part for storing a carbon nanotube injection liquid mixed with a solvent in a solvent; A spray nozzle connected to the carbon nanotube spray liquid storage part and including a plurality of ejection openings; A delivery bed wherein the hook or loop side of the conductive velcro is positioned to face upward and in which the conductive velcro is seated; A transfer unit for transferring the pre-transfer bed in a predetermined direction; And a controller for controlling the spray nozzle to inject a predetermined amount of the carbon nanotube spray liquid onto the hook or loop surface of the conductive velcro when the transporting bed is positioned below the spray nozzle.

In addition, the control unit is connected to the image unit, and the image unit captures the hook or loop surface of the conductive Velcro from above, and the control unit can calculate the surface fraction of the carbon nanotube injection liquid based on the captured image .

In addition, the controller can control the carbon nanotube injection amount such that the fraction of the carbon nanotubes on the two-dimensional plane of the surface on which the conductive velcro is formed is 28.5% or more.

By coating carbon nanotubes on the hook and loop surfaces of the conductive velcro, the present invention can significantly reduce the electrical contact resistance occurring on the contact surface of the conductive velcro.

1 (a) shows a state in which a carbon nanotube and a solvent are mixed and thereafter is not subjected to an ultrasonic dispersion treatment. FIG. 1 (b) shows a state in which a carbon nanotube and a solvent are mixed, do.
FIG. 2 (a) schematically illustrates spraying a carbon nanotube spray liquid onto a conductive velcro. FIG. 2 (b) shows a state in which a conductive velcro is dipped in a solvent containing carbon nanotubes, And is turned upside down so as to be dried.
FIG. 3 (a) shows a surface of a conductive maclec hook without a carbon nanotube coating, FIG. 3 (b) shows a conductive velcro hook surface after immersing the conductive velcro in a solvent containing carbon nanotubes not subjected to ultrasonic dispersion treatment, And FIG. 3 (c) shows a state in which a solvent containing carbon nanotubes subjected to ultrasonic dispersion treatment is sprayed onto the surface of a conductive velcro hook by a spray method.
FIG. 4 is a graph showing a magnification of a state in which a solvent containing carbon nanotubes subjected to the ultrasonic dispersion treatment shown in FIG. 3 (c) is sprayed onto the surface of a conductive velcro hook by spraying.
FIG. 5 shows a state in which a solvent containing carbon nanotubes subjected to an ultrasonic dispersion treatment is sprayed onto a surface of a conductive Velcro loop by a spraying method and the magnification is enlarged.
Fig. 6 shows the surface of the conductive velcro hook according to the difference in spray amount by the spray method.
FIG. 7 is a graph showing the measured electrical contact resistance of the conductive Velcro according to the difference in spray amount by the spray method. FIG.
8 shows a photograph and a conceptual diagram of a fine wear test apparatus for measuring the electrical contact resistance of the conductive Velcro.
Fig. 9 (a) is a graph of the electrical contact resistance of conductive velcro-free carbon nanotubes measured for 3600 cycles at an amplitude of ± 10 μm, ± 25 μm, ± 50 μm, ± 100 μm, FIG. Fig. 9 (b) shows a graph of the electrical contact resistance of the conductive velcro including the carbon nanotubes and the conductive velcro including the carbon nanotubes at the amplitude of +/- 10 [micro] m, respectively.
10 (a) is a graph showing a change in contact resistance of a conductive velcro that does not include carbon nanotubes according to an applied voltage. FIG. 10 (b) A graph showing a change in resistance.
Figs. 11 (a) and 11 (b) are graphs of changes in electrical contact resistance with time when carbon nanotubes were applied to conductive velcro by a spray method and a dipping method, respectively.
12 is a configuration diagram of a conductive velcro manufacturing apparatus including the carbon nanotube of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Prior to the description, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical concept of the present invention.

Throughout this specification, when an element is referred to as "including" an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of the steps, and each step may be performed differently from the stated order unless clearly specified in the context. have. That is, each of the steps may be performed in the same order as the specified order, substantially simultaneously or in the reverse order.

The method for manufacturing a conductive Velcro 100 including the carbon nanotubes 110 according to the present invention includes the steps of mixing carbon nanotubes 110 with a solvent and ultrasonic dispersing the carbon nanotubes 110; Providing a conductive velcro (100) having hook and loop surfaces (121, 122) of conductive velcro positioned on top; And a spraying step of spraying the carbon nanotubes (110) spray liquid onto the hook and loop surfaces (121, 122) of the conductive velcro.

In the step of injecting the carbon nanotubes 110, the carbon nanotubes 110 are mixed with a solvent, followed by ultrasonic dispersion treatment. Specifically, 2 to 4 g of the carbon nanotubes (110) are mixed at a ratio of 140 to 160 ml of a solvent, followed by ultrasonic dispersion treatment for 110 to 130 minutes. In the ultrasonic dispersion treatment, it is repeated 4 times for about 9 to 11 minutes after the ultrasonic treatment for about 27.5 minutes to 32.5 minutes.

The solvent may be an organic solvent, and more preferably acetone.

1 (a) shows a state in which a carbon nanotube and a solvent are mixed and thereafter is not subjected to an ultrasonic dispersion treatment. FIG. 1 (b) shows a state in which a carbon nanotube and a solvent are mixed, do.

In FIG. 1 (a), the carbon nanotubes 110 are clustered and floated on the floor, whereas in FIG. 1 (b), the carbon nanotubes 110 float in the solvent. Accordingly, by performing the ultrasonic dispersion treatment, it is possible to prevent the carbon nanotubes 110 from being clustered, to prevent the solvent and the carbon nanotubes 110 from sinking to the bottom surface of the velcro by the mass of the carbon nanotubes 110 itself, 110 are located on the hook and loop surfaces 121, 122 of the Velcro.

In the step of providing the conductive velcro 100, the hook and loop surfaces 121 and 122 of the conductive velcro are positioned to face upward.

FIG. 2 (a) is a schematic view of spraying the sprayed liquid of the carbon nanotubes 110 onto the conductive velcro 100, and FIG. 2 (b) 100), and then the surfaces (121, 122) of the conductive velcro are turned downward and dried.

2 (a), a method of spraying the sprayed liquid of the carbon nanotubes 110 from above is referred to as a spray method, and after immersing the conductive velcro 100 as shown in FIG. 2 (b) The method of drying upside down is called dipping method.

When spraying the carbon nanotubes 110 by spraying, the spraying device 300 may be used, and the material of the spraying device is preferably a PET material that does not react with the solvent.

FIG. 3 (a) shows a surface of a conductive maclec hook without a carbon nanotube coating, FIG. 3 (b) shows a conductive velcro hook surface after immersing the conductive velcro in a solvent containing carbon nanotubes not subjected to ultrasonic dispersion treatment, And FIG. 3 (c) shows a state in which a solvent containing carbon nanotubes subjected to an ultrasonic dispersion treatment is sprayed onto the surface of a conductive velcro hook by spraying.

As shown in FIG. 3 (b), the non-dispersed carbon nanotubes 110 are clustered to form a cluster, and when the particles are immersed in the carbon nanotubes 110, the carbon nanotubes 110 are affected by the flow of the solvent, gravity, The carbon nanotubes 110 can not be trapped in the carbon nanotubes 121 and mostly sink to the bottom surface. However, as shown in FIG. 3 (c), the carbon nanotubes 110 dispersed are different in size It can be confirmed that it is attached.

FIG. 4 is a graph showing a magnification of a state in which the solvent containing the carbon nanotubes 110 subjected to the ultrasonic dispersion treatment shown in FIG. 3 (c) is sprayed onto the conductive velcro hook surface 121 by spraying. As shown in FIG. 4, it can be confirmed that a cluster of carbon nanotubes 110 is placed on the conductive hook-and-loop hook surface 121.

FIG. 5 is a photograph showing a state in which the solvent containing the carbon nanotubes 110 subjected to the ultrasonic dispersion treatment is sprayed onto the conductive velcro loop surface 122 by spraying to increase the magnification. It can be confirmed that the carbon nanotubes 110 are clustered on the loop surface 122 like the hook surface 121.

6 shows a state of the conductive velcro hook surface 121 as the injection amount by the spray method is changed. 7 is a graph showing the electrical contact resistance of the conductive Velcro 100 measured by varying the spray amount by the spray method.

The fraction of carbon nanotubes on the two-dimensional plane of the surface on which the conductive velcro is formed increases by 3.79%, 15.82%, 28.50%, and 38.21%, respectively, by 1, 2, 3, . In each case, the fine wear test was performed under the conditions of the amplitude of 10 m and the frequency of 10 Hz. As a result, the fraction was 3.79%, 15.82%, 28.50%, and 38.21% , 3 times of injection and 4 times of injection), the electrical contact resistance was 0.71 Ω, 0.28 Ω, 0.11 Ω, and 0.11 Ω (28.50%, 38.21% And the electric contact resistance is lowered as the fraction of the carbon nanotubes 110 is higher. However, when the applied amount is more than about 28.5%, it can be confirmed that the value of the electric contact resistance no longer decreases. Therefore, it is necessary to apply the fraction of the carbon nanotubes on the two-dimensional plane of the surface on which the conductive velcro is formed to about 28.5% to achieve the optimum performance of the carbon nanotube 110.

8 shows a photograph and a conceptual diagram of the fine wear test apparatus 200 for measuring the electrical contact resistance of the conductive Velcro 100. As shown in FIG. The amplitude of the eccentric cam 220 can be adjusted by adjusting the gap between the axis of the motor of the fine wear test apparatus and the eccentric cam 220. The fine oscillation frequency can be controlled by controlling the rotation speed of the motor. It can be realized from 1Hz to 23Hz. The natural frequency of the device is 29.75Hz, 59.50Hz.

9 (a) shows a conductive Velcro 100 without the carbon nanotubes 110 measured for 3600 cycles at an amplitude of ± 10 μm, ± 25 μm, ± 50 μm, ± 100 μm and a current of 0.1 A, Of Fig.

At 7 ~ 10Hz vibration, Velcro abrasion proceeds rapidly and the contact area decreases. Therefore, it shows the highest resistance at 7 ~ 10Hz frequency. When the amplitudes are ± 10 μm and ± 25 μm, the resistance increases greatly at 7 to 10 Hz, but when the amplitude is ± 50 μm, the resistance increases slowly at 7 to 10 Hz. In electrical connectors, the smaller the amplitude, the faster the abrasion occurs. The higher the frequency, the faster the abrasion occurs. However, if the vibration speed is faster than the specific speed, Rather, resistance is lowered.

9B is a graph showing the relationship between the conductive velcro (□ display experiment data) containing no carbon nanotubes 110 and the electric conductivity of the conductive velcro (○ display experiment data) including the carbon nanotubes 110 at ± 10 μm amplitude, And a graph of contact resistance.

 The electrical contact resistance of the conductive Velcro 100 including the carbon nanotubes 110 is much lower to about 0.09 to 0.11 OMEGA, and the change of the electrical contact resistance hardly appears at each frequency. This is an average of about 80% reduction in the electrical contact resistance of the conductive Velcro without the carbon nanotubes 110. [ This is because surface wear due to the vibration characteristics of the conductive Velcro 100 is reduced by the carbon nanotubes 110.

10 (a) is a graph showing a change in contact resistance of the conductive Velcro that does not include the carbon nanotubes 110 according to the applied voltage. FIG. 10 (b) And the contact resistance of the conductive Velcro 100 is measured.

As shown in FIG. 10 (a), at 5 or 15 Hz, the current rises steadily with the applied voltage rising relatively linearly, but at 10 Hz, the shape of the curve is different. The change in the current value according to the Ohm's law is a value obtained by dividing the voltage by the resistance, so that the slope of the curve in Fig. 10 can be said to be the inverse of the resistance. Therefore, in case of 10Hz, the resistance gradually increases as the applied voltage increases. This is because it is thought that the resistance is increased due to the surface damage due to the Velcro vibration characteristics in the 10 Hz region. As the applied voltage increases, the contact surface increases due to the increase of the temperature and the resistance is lowered due to the breakdown of the oxide film.

On the other hand, as shown in Fig. 10 (b), the graphs of the respective frequencies are not significantly different. This is because the influence of the vibration characteristics generated at 10 Hz by the carbon nanotubes 110 on the current is insignificant. In particular, the inclusion of the carbon nanotubes 110 is much higher than that of the case where the carbon nanotubes 110 are not included. This is because the total resistance is reduced due to the application of the carbon nanotubes 110, so a large amount of current flows when a small voltage is applied. The application of the carbon nanotubes 110 is sensitive to a small current and gives a characteristic that represents a current value with respect to an applied voltage relatively linearly without being influenced by a specific variable (frequency) As a sensor that must respond constantly.

11A and 11B are graphs showing changes in electrical contact resistance with time when the carbon nanotubes 110 are applied to the conductive Velcro 100 by a spray method and a dipping method, respectively. When the carbon nanotubes (110) are applied by the spray method, the graph is stabilized as a whole rather than by the dipping method, and there are not many places where the resistance value changes abruptly. This is because even when the carbon nanotubes 110 are dispersed evenly on the conductive velcro surfaces 121 and 122 by the spray method and the conductive velcro surfaces 121 and 122 are damaged by the fine wear test, the carbon nanotubes 110 and 122, ) Effectively suppress the increase of the resistance. On the other hand, in the case of the dipping method, the carbon nanotubes are not well dispersed, and the resistance value suddenly fluctuates suddenly, and as time goes on, the wear progresses and the resistance value gradually increases.

The conductive Velcro 100 including the carbon nanotubes 110 according to the present invention may include a step of mixing the carbon nanotubes 110 with a solvent and performing an ultrasonic dispersion treatment on the carbon nanotubes 110; Providing a conductive velcro (100) having hook and loop surfaces (121, 122) of conductive velcro positioned on top; And a spraying step in which the spray liquid of carbon nanotubes (110) is sprayed onto the hook and loop surfaces (121, 122) of the conductive velcro.

Further, the conductive Velcro 100 including the carbon nanotubes 110 of the present invention can be applied to smart clothes as a connector because the electric contact resistance is very small.

12 is a configuration diagram of a conductive velcro manufacturing apparatus including the carbon nanotube of the present invention.

The apparatus 400 for manufacturing conductive velcro comprising a carbon nanotube according to an embodiment of the present invention includes a carbon nanotube injection liquid storage part (not shown) for storing a carbon nanotube injection liquid mixed with a solvent 410); A spray nozzle 430 connected to the carbon nanotube spray liquid storage part 410 and including a plurality of ejection openings 431; A conveying bed 440 on which the hook or loop face of the conductive velcro is positioned to face upward and on which the conductive velcro is seated; A transfer unit 450 for transferring the transfer bed 440 in a predetermined direction; And a controller 420 for controlling the spray nozzle 430 to spray a predetermined amount of the carbon nanotube spray liquid onto the upper surface of the hook or loop of the conductive velcro when the transporting bed 440 is positioned below the spray nozzle 430, ).

The control unit 420 is connected to a video unit (not shown), and the video unit (not shown) captures a hook or loop surface of the conductive velcro from the top. The surface fraction of the carbon nanotube spray liquid means the ratio of the carbon nanotube spray liquid on the hook or loop surface of the conductive velcro.

The controller 420 controls the carbon nanotubes to be injected by 28.5% or more on the two-dimensional plane of the surface on which the conductive Velcro is formed. The higher the fraction of the carbon nanotubes 110, the lower the electrical contact resistance. However, when the applied amount is more than about 28.5%, the value of the electrical contact resistance no longer decreases. Therefore, the fraction of the carbon nanotubes occupied on the two-dimensional plane of the surface on which the conductive Velcro is formed should be applied to 28.5% to achieve the optimum performance of the carbon nanotube 110.

 By coating the carbon nanotubes on the hook and loop surfaces of the conductive Velcro, the electrical contact resistance occurring on the contact surface of the conductive Velcro can be significantly reduced.

It is to be understood that the invention is not limited to the particular embodiments and descriptions described herein, and that various modifications may be made by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. , Such variations are within the scope of protection of the present invention.

100: conductive Velcro 110: carbon nanotubes (110)
120: Velcro surface 121: Velcro hook surface
122: Velcro loop surface 130: Conductive Velcro bottom
200: fine wear device 210: plate spring
220: eccentric cam 230: fixed plate
300: Injection device
400: Conductive velcro manufacturing device comprising carbon nanotubes.
410: Carbon nanotube injection liquid storage part 420: Control part
430: Spray nozzle 431: Spout nozzle
440: Feeding bed 450: Feeding part

Claims (15)

A step of mixing the carbon nanotubes in a solvent and subjecting the carbon nanotubes to an ultrasonic dispersion treatment;
Providing a conductive velcro having a hook and loop surface of conductive velcro positioned thereon; And
And a spraying step of spraying the carbon nanotube spray liquid onto the hook and loop surfaces of the conductive velcro,
Wherein the carbon nanotube is sprayed on the two-dimensional plane of the surface on which the conductive velcro is formed so that the fraction occupied by the carbon nanotubes is 28.5% or more in the spraying step. .
The method according to claim 1,
Wherein the solvent is an organic solvent.
3. The method of claim 2,
Wherein the organic solvent is acetone. ≪ RTI ID = 0.0 > 11. < / RTI >
The method according to claim 1,
In the step of providing the carbon nanotube spray liquid, 2 to 4 g of carbon nanotubes are mixed in a ratio of 140 to 160 ml of solvent, and ultrasonic dispersion treatment is performed for 110 to 130 minutes. Way.
delete delete delete delete delete delete A carbon nanotube injection liquid storage part for storing a carbon nanotube injection liquid mixed with a carbon nanotube in a solvent and dispersed ultrasonically;
A spray nozzle connected to the carbon nanotube spray liquid storage part and including a plurality of ejection openings;
A delivery bed wherein the hook or loop side of the conductive velcro is positioned to face upward and in which the conductive velcro is seated;
A transfer unit for transferring the transfer bed in a predetermined direction;
And a controller for controlling the spray nozzle to inject a predetermined amount of the carbon nanotube spray liquid onto the hook or loop surface of the conductive velcro when the transporting bed is located below the spray nozzle,
Wherein the control unit adjusts the amount of carbon nanotubes injected so that a fraction occupied by the carbon nanotubes on the two-dimensional plane of the surface on which the conductive velcro is formed is 28.5% or more. Conductive Velcro manufacturing device.
delete delete 12. The method of claim 11,
Wherein the control unit is connected to an image unit, the image unit captures the hook or loop surface of the conductive Velcro from the top, and the control unit calculates the surface fraction of the carbon nanotube injection liquid based on the photographed image Wherein the carbon nanotube is a carbon nanotube.
delete

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