This application claims the priority benefit of Taiwan application serial no. 104131452, filed on Sep. 23, 2015. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
Field of the Invention
The invention relates to a straightening device and a particle production apparatus using the same.
Description of Related Art
Along with the continuous development of an application field of nanopowder, demand on quantity of nanoparticles has continuously increased, and in order to satisfy the demand of the nanoparticles, related practitioners devote to research and develop a mass production technique and an apparatus capable of improving productivity of the nanopowder while considering a property of the nanoparticles and production safety thereof.
Some practitioners produce the nanoparticles by using a chemical approach, during a manufacturing process adopting the chemical approach, since a chemical activity of the nanoparticles is required to adopt a proper reactant, besides some precious metals, the chemical approach is not suitable for producing general metal nanoparticles, and the manufacturing cost of the chemical approach is relatively high, and particle size distribution is relatively wide range. Some other practitioners produce the nanoparticles by using a metal sputtering vapour synthesis method, by which the particle size of the nanoparticles can be controlled by controlling a pressure and a temperature of an inert gas and a temperature of an evaporated substance. However, the metal vapour synthesis method has to be implemented under a vacuum environment, which is subjected to considerable restrictions in an actual production application. Therefore, most of the practitioners still produce the nanoparticles for smaller particle sizes by using a mechanical grinding method.
Taking a dry grinding method as an example, the powder is driven by the air and the particles are grinded into nanoparticles according to a particle impact principle. However, although the particle sizes of the nanoparticles produced according to the above grinding method are relatively small, during the manufacturing process, the smaller the particle size of the produced particles is, the more easier the particles float in the air to form nano dust, and the minimum ignition energy of the particles becomes smaller, such that the nano dust is easy to be ignited. Regarding a titanium powder and an iron powder with the particle size of a nano scale, the minimum ignition energy thereof is smaller than 1 mJ, and during the manufacturing process, due to the factors of static electricity, impact or open flame, it is extremely easy to cause combustion and explosion, which causes many crises of fires and explosions during the process of manufacturing the nanoparticles.
Accordingly, the invention is directed to a straightening device and a particle production apparatus using the same, in which a metal wire is continuously input to a generating device to continuously generate particles, and the generated particles are distributed in a dense medium, so as to greatly improve productivity and safety of a mass production.
The invention provides a particle production apparatus including a generating device, a conveying device, and a straightening device. The generating device includes a tank, an electric power source, a first electrical conducting element and a second electrical conducting element. The tank is filled with a dense medium in a liquid state. The first electrical conducting element and the second electrical conducting element are disposed in the dense medium of the tank, and are coupled to the electric power source. The conveying device is configured to convey a metal wire into the tank and make the metal wire to contact the first electrical conducting element and the second electrical conducting element, so as to produce an electric explosion to form a plurality of particles in the dense medium when the first electrical conducting element, the second electrical conducting element and the metal wire located therebetween are electrically conducted. The straightening device disposed between the conveying device and the generating device straightens the metal wire along a straight-line direction for transmitting to the generating device, such that the metal wire contacts the first electrical conducting element and the second electrical conducting element along the straight-line direction.
The invention provides a straightening device, which is adapted to straighten a metal wire. The straightening device includes a stage, an ultrasonic source and a pressure head. The metal wire is driven to pass through the stage and is carried by the stage. The pressure head covering the stage is connected to the ultrasonic source, such that an ultrasonic wave is exerted to the metal wire passing through the stage to eliminate an internal stress of the metal wire, so as to straighten the metal wire along a straight-line direction.
According to the above description, the straightening device and the particle production apparatus of the invention may control a length of the metal wire and straighten the same to effectively control a particle size of the particles generated during continuous electric explosion of the metal wire.
In other words, based on arrangement of a shifting device and the conveying device, the length of the metal wire between the first electrical conducting element and the second electrical conducting element may reach the predetermined length, which represents that the particle production apparatus is able to maintain consistency of the length of the metal wire in each electric explosion process, and meanwhile the straightening device may effectively eliminate the internal stress of the metal wire and maintain the shape of the metal wire along a fixed direction for contacting the electric conducting elements, so as to avoid a bending status of the metal wire when the metal wire contacts the electrical conducting elements to influence the quality of the particles obtained through the electric explosion.
Moreover, when a surface contour of the electrical conducting elements is changed due to the previous explosion, the shifting device may adjust a distance between the electrical conducting elements to effectively maintain consistency of the length of the metal wire between the electrical conducting elements.
In order to make the aforementioned and other features and advantages of the invention comprehensible, several exemplary embodiments accompanied with figures are described in detail below.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated and constituted a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A metal wire coil 320 decoils and transmits a metal wire 310 into the dense medium 212 through the conveying device 250. Further, the conveying device 250 includes a motor 253, a driving wheel 251 and a driven wheel 252, where the motor 253 is electrically connected to and controlled by the control device 400 for driving the driving wheel 251 to rotate (meanwhile the driven wheel 252 is driven to rotate), such that the metal wire 310 can be clamped by the driving wheel 251 and the driven wheel 252 for transmitting to the dense medium 212. When the metal wire 310 sequentially contacts the first electrical conducting element 230 and the second electrical conducting element 240, since the first electrical conducting element 230, the second electrical conducting element 240 and the metal wire 310 therebetween are electrically conducted, a voltage can be provided to produce an electric explosion of the metal wire 310 to form a plurality of metal particles or metal compound particles in the dense medium 212. The voltage required for producing the electric explosion is, for example, 12V to 100V, which is determined by a length and a diameter of the metal wire 310, and compared with the existing technique that a high voltage (several kilovolts) is required to achieve the electric explosion, the invention has obvious effectiveness and safety.
In the present embodiment, the shifting device 260 is disposed opposite to the conveying device 250. The shifting device 260 includes an actuator 261 and a supporter 262, where the actuator 261 is, for example, a step motor, a voice coil motor, an oil hydraulic motor, a piezoelectric actuator, etc., which is electrically connected to the control device 400, and is controlled by the same to move back and forth to shift the supporter 262 (shown as a double arrow direction of
Referring to
Moreover, the particle production apparatus 10 of the present embodiment further includes a clamping device 270, which is electrically connected to the control device 400 and is driven by the control device 400 to open and close relatively to the first electrical conducting element 230. As shown in
However, the method for adjusting the length of the metal wire 310 between the first electrical conducting element 230 and the second electrical conducting element 240 is not limited by the present embodiment.
It should be noted that in the embodiment of
After the metal wire 310 produces the electric explosion, in step S360, the control device 400 detects whether the metal wire 310, the first electrical conducting element 230 and the second electrical conducting element 240 are electrically conducted, i.e., the control device 400 detects whether the metal wire 310, the first electrical conducting element 230 and the second electrical conducting element 240 are electrically conducted after a predetermined time Δt (for example, at least 0.001 second), so as to determine whether the electric explosion is complete. If not, i.e., the first electrical conducting element 230 and the second electrical conducting element 240 are not electrically conducted, the control device 400 controls the electric power source 220 to modulate and output the predetermined detection voltage, i.e., the flow returns to the step S310 to confirm the electric conduction state between the first electrical conducting element 230 and the second electrical conducting element 240 by using the detection voltage.
Conversely, after the predetermined time Δt, when the control device 400 detects that the first electrical conducting element 230 and the second electrical conducting element 240 are still electrically conducted, it represents that the previous electric explosion is not successfully produced, and in step S370, the control device 400 controls to cut off the input voltage between the first electrical conducting element 230 and the second electrical conducting element 240, so as to avoid a short circuit of the system. It should be noted that the operation flow of
Moreover, it should be noted that as describe above, the shifting device 260 can shift the second electrical conducting element 240 to adjust the distance between the second electrical conducting element 240 and the first electrical conducting element 230, so that in the step S320 of the present embodiment, when the control device 400 detects that a surface of the second electrical conducting element 240 is uplifted through the operation of conveying the metal wire 310 by using the conveying device 250, the control device 400 drives the shifting device 260 to move the second electrical conducting element 240 away from the first electrical conducting element 230, such that the metal wire 310 between the first electrical conducting element 230 and the second electrical conducting element 240 is maintained to the aforementioned predetermined length L1.
In detail, the length of the metal wire 310 conveyed by the conveying device 250 is a fixed setting value (i.e., the aforementioned predetermined length L1), so that after the previous electric explosion is completed, the metal wire 310 is again conveyed by the setting value by the conveying device 250. However, when the surface of the second electrical conducting element 240 is uplifted due to deposition of the particles generated in the previous electric explosion, the metal wire 310 may contact the second electrical conducting element 240 to implement electrical conduction before it is conveyed by the predetermined length L1, and now the length of the metal wire 310 used for implementing the electric explosion is substantially smaller than the predetermined length L1. Therefore, the control device 400 takes a difference between the length of the currently conveyed metal wire 310 and the predetermined length L1 as a reference for driving the shifting device 260 to move the second electrical conducting element 240 away from the first electrical conducting element 230, and meanwhile controls the conveying device 250 to continually convey the metal wire 310 to the predetermined length L1, such that the present electric explosion can still be implemented under the state that the metal wire 310 is maintained to the predetermined length L1. In this way, the particle quality (particle size distribution) of each electric explosion is effectively maintained.
Conversely, when the surface of the second electrical conducting element 240 is pitted due to the previous electric explosion, the metal wire 310 cannot contact the second electrical conducting element 240 to implement electrical conduction after it is conveyed by the predetermined length L1, and now the conveying device 250 continually conveys the metal wire 310 to exceed the predetermined length L1 until the metal wire 310 contacts the second electrical conducting element 240 to implement the electrical conduction. The control device 400 then detects a length of the metal wire 310 exceeding the predetermined length L1, and takes the exceeding length as a reference for driving the shifting device 260 to move the second electrical conducting element 240 toward the first electrical conducting element 230, and meanwhile controls the conveying device 250 to draw back the metal wire 310, such that the electric explosion can still be implemented under the state that the metal wire 310 is maintained to the predetermined length L1.
Moreover, the straightening device 100 further includes a pipe 150 (only a part of which is illustrated), which is disposed between the aforementioned straightening roller set and the first electrical conducting element 230. The pipe 150 extends along the straight-line direction D1, and the metal wire 310 penetrates through the pipe 150 and is straightened along the straight-line direction D1. Meanwhile, the pipe 150 guides the metal wire 310 to the first electrical conducting element 230.
Moreover, in another embodiment that is not illustrated, the straightening device may also include an electrical pulse straightening module, i.e., after a decoiling or coiling device bracing the metal wire, the metal wire is heated by a high-energy electrical pulse, and when the metal wire is softened, it is stretched by using a mould, so as to obtain the metal wire with better collimation and eliminate an internal stress therein.
According to the above description, the metal wire 310 with a wire diameter smaller than 1 mm can be straightened by the aforementioned straightening device 100 or 100A and transmitted into the dense medium 212 to implement the electric explosion, so as to effectively avoid quality unstableness of the electric explosion due to bending or deformation of the metal wire 310 occurred during a conveying process thereof.
On the other hand, referring to
Moreover, the particle production apparatus 10 further includes a temperature control device 290 disposed at the tank 210 for adjusting a temperature of the dense medium 212 in the tank 210. Taking a copper wire as an example, the copper wire may have different patterns after the electric explosion in deionized water under different temperatures, where when the temperature of the deionized water is 1° C., the copper wire forms spherical copper particles after the electric explosion, and when the temperature of the deionized water is 60° C., the copper wire forms spindly copper oxide after the electric explosion. In this way, the user may operate the temperature control device 290 through the control device 400 to make the dense medium 212 to reach a request temperature.
Moreover,
In summary, in the embodiments of the invention, the straightening device and the particle production apparatus of the invention may control a length of the metal wire and straighten the same to effectively control a particle size of the particles generated during continuous electric explosion of the metal wire.
The shifting device is used for adjusting a distance between the second electrical conducting element and the first electrical conducting element. When a contour of the surface of the second electrical conducting element is changed due to the previous electric explosion, the length of the metal wire prepared for the next electric explosion is liable to be inconsistent, so that by using the conveying device in collaboration with the shifting device, the length of the metal wire between the first electrical conducting element and the second electrical conducting element may reach the predetermined length, so as to maintain the consistency of the length of the metal wire to guarantee the quality (particle size distribution) of the particles obtained after the electric explosion.
Moreover, the straightening device is used for performing a straightening operation on the metal wire, such that the metal wire is maintained straight at the moment of contacting the second electrical conducting element, and according to such move, consistency of the length of the metal in each electric explosion is maintained to guarantee the quality of the particles obtained after the electric explosion. In the aforementioned embodiments, besides the pipe with a specific extending direction being adopted to straighten the metal wire, the ultrasonic wave or electrical pulse heating can also be adopted to straighten the metal wire and eliminate the internal stress of the metal wire.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Number | Date | Country | Kind |
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Number | Date | Country | |
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