JP2005105377A - Device for generating aerosol, and apparatus for producing composite structure provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for generating aerosol, which generates aerosol having a constant concentration for a long period, and aerosol free from coarse particle. <P>SOLUTION: The device for generating aerosol comprises a powder-storing section for storing a powder consisting of fine particles made of a brittle material; a transporting means arranged in the powder-storing section so that one part of the means can contact with the powder; an aerosolizing section for dispersing the powder transported by the transporting means into a gas; and a scraper section. The transporting means is installed so as to tilt with respect to a gravity direction. One part of the powder is transported toward the direction opposing the gravity by the transporting means, and is supplied to the aerosolizing section though the scraper section. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an aerosol generator that generates aerosol by dispersing powder in a gas, and in particular, an aerosol in which fine particles of a brittle material are dispersed in a gas is sprayed onto a substrate to form a structure made of a constituent material of the fine particles. The invention relates to an aerosol generator suitable for a composite structure manufacturing apparatus formed on a substrate.

  As a method for forming a structure mainly composed of a brittle material on the surface of a substrate, a technique called an aerosol deposition method has been recognized. This is because an aerosol in which fine particles such as brittle materials are dispersed in a gas is sprayed from the nozzle toward the base material, and the fine particles collide with the base material such as metal, glass, ceramics, and plastic. It is characterized in that the fine particles are deformed or crushed and joined together to directly form the structure made of the constituent material of the fine particles on the base material, and the structure can be formed especially at room temperature that does not require heating means. In the process, a structure having mechanical strength equivalent to the fired body can be obtained. The apparatus used in this method basically consists of an aerosol generator for generating aerosol and a nozzle for injecting the aerosol toward the base material. When a structure is produced with a larger area than the opening of the nozzle, In addition, it has a position control means that moves and swings the base material and the nozzle relative to each other, and has a chamber and a vacuum pump for forming a structure when producing under reduced pressure, and also generates aerosol It is common to have a gas source.

  The process temperature of the aerosol deposition method is room temperature, and one feature is that the structure is formed at a temperature sufficiently lower than the melting point of the particulate material, that is, several hundred degrees C. or less.

  The fine particles used are mainly brittle materials such as ceramics and semiconductors, and can be used by mixing or combining different kinds of fine particles of brittle materials, and some metal materials and organic materials can be used as brittle materials. It can also be used by mixing with fine particles or coating the surface of brittle material fine particles. Even in these cases, the main component of structure formation is a brittle material.

  In a structure formed by this method, when crystalline brittle material fine particles are used as a raw material, the brittle material portion of the structure is a polycrystalline body whose crystallite size is smaller than that of the raw material fine particles, In many cases, crystals have substantially no crystal orientation, and it can be said that there is substantially no grain boundary layer composed of a glass layer at the interface between brittle material crystals, and part of the structure bites into the substrate surface. The anchor layer is often formed.

  The structure formed by this method clearly has a sufficient strength unlike a so-called green compact in which fine particles are packed by pressure and keeps a form by physical adhesion.

  In this structure formation, the brittle material fine particles are crushed and deformed by measuring the brittle material fine particles used as a raw material and the crystallite size of the formed brittle material structure by X-ray diffraction. it can. That is, the crystallite size of the structure formed by the aerosol deposition method is greatly characterized by being smaller than the crystallite size of the raw material fine particles. A new surface in which atoms originally present inside and bonded to other atoms are exposed is formed on the slip surface or fracture surface formed by crushing or deforming fine particles. This active new surface having a high surface energy is considered to be formed by joining the surface of the adjacent brittle material, the new surface of the adjacent brittle material, or the substrate surface. In addition, when hydroxyl groups are present on the surface of the fine particles moderately, a mechanochemical acid-base dehydration reaction occurs due to local shear stress generated between the fine particles and between the fine particles and the structure when the fine particles collide with each other. It can be considered. The addition of continuous mechanical impact force from the outside causes these phenomena to occur continuously, and the progress and densification of joints are performed by repeated deformation and crushing of fine particles, and brittle material structures grow. it is conceivable that.

Conventionally, there is a table feeder as an apparatus of this type, and a disk table that is driven to rotate as shown in FIG. 12 and extends from the outside to the inside and is fixed to a frame so that the position can be adjusted in the vertical direction. A first scraper that forms a powder layer with a uniform thickness on the table, and a granular material that is fixed to a frame along the periphery of the table and moves in the outer peripheral direction of the table by the first scraper. A guide plate that is maintained on the table, extends from the outside of the table to the inside, is fixed to a frame so that the position of the table can be adjusted in the horizontal direction, and scrapes off the granular material layer formed by the first scraper to powder into the discharge pipe. Proposed with a second scraper for feeding the body. (See Patent Document 1)

However, when the above-described powder supply apparatus is used as an aerosol generation apparatus in the aerosol deposition method, most of the powder is discharged out of the rotary table in the process of forming the powder into a uniform layer by the first scraper. . For this reason, the specification efficiency of the powder is poor and is not practical. In particular, when the powder is expensive, practical application becomes more difficult. Further, it is possible to add the circulation mechanism and reuse the discharged powder, but the apparatus becomes complicated and causes impurities to be mixed in the powder conveying process. Further, in the case of the aerosol deposition method, since the powder conveyance is performed in a vacuum, it is necessary to store the circulating device to be installed in the vacuum system, so that the complexity and size of the device are greatly increased.
Further problematic is the conveyance of the agglomerated powder. Since the powder used in the aerosol deposition method is a fine powder, it has a strong cohesive force and poor transportability. For this reason, most of the powder conveyed to the second scraper is agglomerated and eventually agglomerated particles develop and are supplied as coarse particles to the discharge pipe. In our experiments, the size of the coarse particles is There are some that reach about 3 mm, and this has caused a problem that the composite structure cannot be stably produced by the aerosol deposition method.

JP 2-145924

  The present invention has been made to solve the above problems, and an object of the present invention is to generate an aerosol at a stable concentration for a long time and to generate an aerosol containing no coarse particles. Is to provide a simple aerosol generating device.

In order to achieve the above object, according to the first aspect of the present invention, an aerosol in which fine particles of a brittle material are dispersed in a gas is sprayed from a nozzle toward a base material, and the aerosol is made to collide with the substrate surface. An aerosol generator for use in a composite structure manufacturing apparatus for crushing, deforming and joining the fine particles by the impact of the collision, and forming a structure made of the constituent material of the fine particles on the base material. A generator containing a powder made of fine particles of the brittle material; conveying means installed in the powder containing part and in contact with the powder; and the powder An aerosolizing unit that disperses a body in a gas; and a scraper unit that adjusts the shape of the powder on the conveying unit and guides the powder to the aerosolizing unit. And a part of the powder is conveyed in a direction against gravity by the conveying means, and the held powder is supplied to the aerosolization unit via the scraper unit. To do.
As a result, most of the powder in the powder container is returned to the powder container by the scraper and collected again as a powder for conveyance. Moreover, since the conveying means is inclined with respect to the direction of gravity, the coarse powder particles remain below due to gravity. On the other hand, the powder held and conveyed on the wall surface of the bottom plate in the powder container is supplied to the aerosol generator. According to this method, the powder scraped off by the scraper is returned to the powder container by gravity and can be collected in the powder container. As a result, the use efficiency of the powder can be greatly increased.
Further, the conveying means is inclined with respect to the direction of gravity, and the powder is held by frictional force between the wall surface of the powder container and the powder, or the wall surface of the powder supply unit and the powder. This is due to the frictional force. By this and the action of uniformly forming the powder shape by the scraper, a constant amount of powder can be continuously supplied to the aerosol-generating part, so that a constant concentration of aerosol can be generated. Further, the powder can be classified by changing the surface roughness of the conveying means that affects the frictional force. Furthermore, even if coarse powder particles are mixed in the powder put into the powder container, the coarse powder particles are forced to fall when the powder is held and separated by the frictional force of the wall surface. Coarse powder particles are not supplied to the aerosolization unit.
Furthermore, the aerosol concentration can be controlled by changing the rotational speed of the powder container.

According to a second aspect of the present invention, an aerosol in which fine particles of a brittle material are dispersed in a gas is sprayed from a nozzle toward a base material, the aerosol is made to collide with the substrate surface, and the impact of this collision An aerosol generator for use in a composite structure manufacturing apparatus in which the fine particles are crushed, deformed and bonded, and a structure made of the constituent material of the fine particles is formed on the base material, the aerosol generator being the brittle A powder container that contains powder made of fine particles of material, a powder supply part that is arranged so that a part of the powder is contained in the powder container, and the powder supply part A rotation means for rotating the powder around an axis, an aerosolization part for dispersing the powder in a gas, a scraper part for adjusting the shape of the powder on the rotation means, and guiding the powder to the aerosolization part, The A rotating shaft of the rotating means is inclined with respect to the direction of gravity, and by rotation of the powder supply unit, a part of the powder is conveyed in a direction against gravity, and the held powder is It is supplied to the aerosol generating unit through the scraper unit.
Thus, in addition to the effect of the invention of claim 1, by using the rotary means as the conveying means, the powder returned to the powder container by the first scraper can be reliably recovered and the dead space where the powder accumulates can be obtained. It is possible to construct an almost perfect structure and to simplify the device structure.

  According to a third aspect of the present invention, the conveying means according to the first aspect is a circulation belt, and in addition to the effect of the first aspect of the present invention, Since the amount of powder transport is almost constant at any location, it is possible to install a large number of third scrapers and supply the powder to the aerosol generator by making the belt width of the transport means sufficiently wider than the precision scraper. Thus, a plurality of aerosol outlets can be set from one transport means.

According to the invention of claim 4, the first scraper that makes the scraper part a powder layer having a substantially uniform thickness, the second scraper that adjusts the widthwise end of the powder layer, It has a 3rd scraper which supplies a part of powder of the powder layer formed with the 1st scraper and the 2nd scraper to the aerosol-ized part.
By adjusting the gap between the first coarse scraper and the conveying means to change the thickness of the formed powder, it is possible to classify the powder. Furthermore, even if coarse powder particles are mixed in the powder put into the powder container, the coarse powder particles are forced to fall when the powder is held and separated by the frictional force of the wall surface. It is possible to prevent coarse powder particles from being supplied to the aerosolization unit.

  According to the invention described in claim 5, the powder is held by the frictional force between the powder supply wall and the powder, or the frictional force between the powders, van der Waals force, or static electricity. A certain amount of powder can be continuously supplied to the aerosol-generating unit by the action of uniformly forming the powder shape by the scraper and this, and a constant concentration of aerosol can be generated. Further, the powder can be classified by changing the surface roughness of the conveying means that affects the frictional force or adjusting the gap between the first rough scraper and the conveying means to change the thickness of the formed powder. Furthermore, even if the coarse powder particles are mixed in the powder to be put into the powder container, the coarse powder particles are forced by gravity when the powder is held and separated by the frictional force between the wall surfaces or the powders. Since it is allowed to fall, the coarse powder particles are not supplied to the aerosol-generating part.

According to a sixth aspect of the present invention, the powder is held by at least one protrusion or depression formed on the wall surface of the powder container or the wall surface of the powder supply unit. It is characterized by.
Thus, even a powder that is difficult to hold by the frictional force of the wall surface, for example, a powder that has a very weak frictional force with the wall surface, can be reliably supplied. Moreover, even in the case of powder whose frictional force with the wall surface changes with time, aerosol can be generated for a long time with a stable concentration.

  According to a sixth aspect of the present invention, in the aerosol generation device, the aerosol generation unit is configured by at least a gas introduction unit and an aerosol extraction unit, and the powder supplied from the third scraper is It is characterized by spraying and dispersing the gas introduced from the gas introduction part and deriving from the aerosol derivation part, and this effect and the gravity classification effect in the aerosolization part are added, so coarse particles are more reliably It is possible to generate an aerosol composed of fine particles not containing. Furthermore, only the fine particles existing on the surface can be selectively derived by adjusting the scraping amount of the third scraper to the extreme surface of the conveyed powder.

  According to a seventh aspect of the present invention, the aerosol generating apparatus further comprises a vibration means for applying vibration to a portion for holding the powder. Even when the body and aggregated particles are held, the fall is accelerated by vibration, so that aerosol can be generated at a stable concentration without supplying a large amount of powder or aggregated particles to the aerosolization part. .

  According to an eighth aspect of the present invention, the aerosol generating device further comprises a powder replenishing means for additionally replenishing the powder in the powder container, whereby a long-term aerosol is provided. It is not necessary to stop the device to replenish powder. Alternatively, it is not necessary to enlarge the powder container in order to accommodate a large amount of powder in advance. Also, in the case of a powder whose properties are likely to change due to friction with the rotating powder container or powder supply unit, it is advantageous because the time for receiving the friction is shortened. In addition, if the powder properties change easily due to the weight of the powder itself when a large amount of powder is added, it is possible to supply a small amount so as not to be affected, so that the powder can be supplied more stably. Become.

  According to a ninth aspect of the present invention, in the aerosol generating apparatus, a heating mechanism is provided at a portion in contact with the powder, whereby the aerosol is generated for a long time and the powder adheres to the scraper. Blocking and bridging of parts can be prevented. The powder contains some moisture, which promotes adhesion and aggregation. By constantly removing moisture with heat, stable powder properties can be maintained, that is, stable powder supply becomes possible.

  According to a tenth aspect of the present invention, the aerosol generating apparatus is characterized in that the scraper portion is provided with an ultrasonic vibrator, thereby providing an effect of crushing the aggregated particles. Even when the agglomerated particles cause bridging in the gap between the scraper and the conveyor, the powder can be broken into fine particles by ultrasonic vibration of the scraper to suppress bridging. As a result, stable supply is possible, and the development of aggregated grains and coarse grains is suppressed.

  According to the eleventh aspect of the present invention, in the aerosol generating apparatus, the third scraper portion can be positioned with respect to the powder conveying means by an actuator or the like, whereby the powder is aerosolized. It becomes possible to control the supply amount to the section. That is, the amount of powder to be scraped can be adjusted by adjusting the gap between the third scraper and the conveying means in the previous period, and the concentration of the aerosol is finely adjusted by supplying the scraped powder to the aerosol-generating unit. be able to,

Moreover, according to invention of Claim 12, it is a composite structure preparation apparatus provided with the aerosol generator and the nozzle for spraying an aerosol on a base material, Comprising: The aerosol generation of Claims 1-11 as an aerosol generator A device is provided.
Accordingly, aerosol can be generated for a long time at a stable concentration, and thus a composite structure with little variation in physical properties can be efficiently produced. In addition, since no coarse dust particles are generated, the coarse dust particles are not mixed in the aerosol to cause defects in the composite structure.

  ADVANTAGE OF THE INVENTION According to this invention, the aerosol generator which can generate an aerosol for a long time with the stable density | concentration and can generate the aerosol which does not contain a coarse particle can be provided.

Hereinafter, the best mode for carrying out the invention will be described in detail with reference to the drawings.
First, a general configuration example of a composite structure manufacturing apparatus including an aerosol generator according to the present invention will be described with reference to FIG. A gas cylinder 51 containing nitrogen is connected to an aerosol generator 53 via a hose-shaped transfer pipe 52, and further includes an opening having a circular introduction part and a rectangular opening in the structure forming chamber 54 through the transfer pipe 52. A nozzle 55 is installed. A base material 56 is arranged opposite to the nozzle 55 on a substrate holder 57 that can be braked vertically (Z), front-back, left-right (XY) by a control means (not shown). The structure forming chamber 54 is connected to an exhaust pump 58.

  In addition, a sensor device 61 for measuring the aerosol concentration is disposed between the nozzle 55 and the base material 56, and a signal output from the sensor device 61 is sent to the feedback control circuit 62 and processed to generate an aerosol generator. Control is performed so as to control the aerosol concentration and to supply an arbitrary amount of aerosol that collides with the substrate.

  Next, the configuration of one embodiment of the aerosol generator according to the present invention will be described. FIG. 2 is an external view of an aerosol generator according to the present invention. The vacuum vessel 71 includes a disk-like vacuum vessel top plate 72, a vacuum vessel bottom plate 73, and a cylindrical vacuum vessel body 74, each of which is airtightly fastened via an O-ring 75, and the vacuum vessel top plate 72 and The vacuum vessel body 74 can be easily attached and detached as necessary. The vacuum vessel 71 is supported by a column 77 via a vacuum vessel holder 76, and the column 77 is fixed to a base plate 78. The vacuum vessel 71 is rotatable around the X axis and can be fixed at an arbitrary angle by a mechanism not shown.

FIG. 3 is a view in which the vacuum vessel 71 in FIG. 2 is fixed at an angle of 45 ° with the vertical direction. Here, the vacuum vessel holder 76, the column 77, and the base plate 78 are not shown.
The vacuum container 71 stores powder 79, and in this example, the vacuum container 71 also serves as the powder storage container 80.
Inside the powder container 80, a disk-shaped powder conveyance table 81 and a first scraper 84, a second scraper 85 and a third scraper 86 for scraping the powder 79 are fixed to the powder container 80. And a predetermined positional relationship with the powder conveying table (FIG. 4), the positional relationship being such that the powder scraping surfaces of the first scraper and the second scraper are relative to the conveying surface of the conveying table 81. It is installed vertically or at an angle of 70 to 120 degrees, and is placed radially on the outer periphery of the transfer table with respect to the shaft 83. The gravity direction is 0 degrees and the clockwise direction is plus 0 degrees to +90 degrees. The second scraper is arranged at a position of +90 degrees to +180 degrees at a position of + and is slightly protruded from the outer periphery of the transport table, and its length is sufficiently shorter than that of the first scraper. That. In addition, the first scraper is arranged with a certain gap from the transport table, but the second scraper is installed with a gap as small as possible though it does not contact the transport table. The third scraper is arranged at a position of + 180 ° to 270 ° with respect to the conveying rotary table, the second scraper is arranged inside the radial position of the rotating table for scraping the powder, and the gap with the conveying table is the first. It is adjusted narrower than the scraper. At this time, the rotation direction of the transfer table is clockwise.

A shaft 83 is fastened to the center of the powder transfer table 81, and an O-ring seal, a V seal, a magnetic seal or the like is interposed as a vacuum seal member between the shaft 83 and a bearing holder for holding the shaft 83. Even if the shaft 83 is rotated around the Y axis in the drawing, the airtightness in the vacuum vessel 71 is not impaired.
The other end of the shaft 83 is connected to a driving device such as a motor via a timing pulley and a timing belt, and the rotation of the powder containing portion 80 about the Y axis inclined with respect to the direction of gravity by the rotating means. It is possible to rotate at speed. An air cylinder 88 serving as a vibration means is also arranged behind the shaft 83 as shown in the figure. By driving the air cylinder 88 by a control / drive means (not shown), the end face of the shaft 83 can be driven at an arbitrary cycle and force. It is possible to hit. As a result, vibration in the Y-axis direction can be applied to the powder container 80 held at the other end of the shaft 83.

FIG. 5 is an enlarged cross-sectional view of the aerosol-generating part 87 shown in FIG. The aerosolization unit 87 includes a gas introduction pipe 91 serving as a gas introduction part and an aerosol lead-out pipe 92 serving as an aerosol lead-out part.
One end of the gas introduction pipe 91 is connected to the transport pipe 52 and the gas cylinder 51 via a joint disposed on the vacuum vessel top plate 72, and the gas introduction port 91, which is the other end, is connected to the aerosol delivery pipe 81 near the powder transport table 81. It is bent in 92 directions. The aerosol lead-out port, which is one end of the aerosol lead-out pipe 92, is connected to the third scraper, and the other end is connected to the transport pipe 52 and the nozzle 55 via a joint disposed on the vacuum vessel top plate 72.
In addition, since the aerosol generating part 87 is being fixed to the vacuum vessel top plate 72, even if it rotates the powder container 80, it does not move.

FIG. 6 is an enlarged cross-sectional view of another form of the aerosol-generating part 87 shown in FIG. The aerosolization unit 87 includes a gas introduction pipe 91 serving as a gas introduction part and an aerosol lead-out pipe 92 serving as an aerosol lead-out part. The gas introduction pipe 91 and the aerosol lead-out pipe are concentric double pipes, and one end of the gas introduction pipe 91 is connected to the transport pipe 52 and the gas cylinder 51 through a joint disposed on the vacuum vessel top plate 72. Yes.
The aerosol lead-out port, which is one end of the aerosol lead-out pipe 92, is disposed above the third scraper, and the other end is connected to the transport pipe 52 and the nozzle 55 via a joint disposed on the vacuum vessel top plate 72. The gas introduction pipe 91 and the aerosol lead-out pipe 92 are branched outside the aerosol container, the gas introduction pipe is bent from the middle and connected to the gas cylinder, and the aerosol lead-out pipe is connected to the nozzle 55 without being bent as much as possible.
In addition, since the aerosol generating part 87 is being fixed to the vacuum vessel top plate 72, even if it rotates the powder container 80, it does not move.

  Next, the operation of one embodiment of the aerosol generator according to the present invention having the above-described configuration will be described. The vacuum vessel 71 is set so that the rotation axis (Y axis) of the shaft 83 is inclined at a desired angle with respect to the direction of gravity. The vacuum container top plate 72 of the vacuum container 71 is opened, and the powder 79 is put into the powder container 80. When the exhaust pump 58 starts exhausting after the vacuum container top 72 is closed, the inside of the vacuum container 71 connected through the structure forming chamber 54, the nozzle 55 and the transfer pipe 52 is decompressed. When the pressure is reduced to a predetermined pressure, the gas is allowed to flow at a predetermined flow rate. After the pressures in the vacuum container 71 and the structure forming chamber 54 become constant, the motor 91 is rotated at a predetermined rotational speed and the air cylinder 88 is driven to apply vibration to the powder container 80. As a result, a substantially constant amount of powder is sent to the aerosolization unit 87.

Here, the principle of powder supply according to the present embodiment will be described in detail. First, the vacuum vessel top plate 72 is removed and the powder 79 is charged. The powder is deposited below the powder container 80 by the force of gravity. Next, when the transfer table 81 is rotated, the transfer of the powder 79 starts. The powder 79 is first scraped off by the first scraper 84, and a small amount passes through a parallel gap between the transfer table and the first scraper 84. To form a powder layer 89 having a uniform thickness. The powder 79 scraped off without being leveled falls to the positions of all the stages of the first scraper 84 by the force of gravity, and is again transported to the first scraper by the transport table, and the transport table and the first scraper 84 are parallel to each other. Circulation and dropping are repeated until it passes through the gap.
The powder layer 89 leveled by the first scraper 84 is held on the transfer table wall surface by the friction force between the transfer table wall surface and the powder, or the friction force between the powders, and reaches the second scraper 85. The shape of the outer periphery of the powder is not stable. For example, the powder may protrude slightly from the transfer table, or the powder layer 89 may be thin and not a continuous layer. The holding force is weak and may fall during transportation. If the powder falls only above the aerosolization part, this powder may be taken into the aerosol outlet tube, which makes the aerosol concentration unstable. The second scraper 85 is installed on the outer periphery of the powder conveying table with almost no gap with the conveying table, scraping off the unstable part of the powder held in the vicinity of the outer peripheral portion, and dropping it. There is an effect to prevent. The powder layer 89 that has passed through the second scraper 85 reaches the third scraper 86, and the third scraper scrapes off the set amount of powder from the powder surface layer portion to supply the powder to the aerosolization portion. The powder layer 89 that has not been scraped off by the third scraper is held on the transport table and transported to the first scraper 84 and circulated.

The powder supply method shown in FIG. 3 will be described in more detail with reference to FIG. 7 is a DD cross section of the rear stage G section that has passed through the first scraper 84 in FIG.
A drop force due to gravity and a frictional force between the powder particles act on the powder particles E that are not in contact with the wall surface of the powder transport table 81.
As the inclination angle of the transfer table is increased, the drop force increases and the friction force between the powder particles decreases, so that the powder particle E falls at an inclination angle that satisfies drop force> powder particle friction force.
Similarly, a drop force due to gravity and a friction force between the powder particles and the wall surface act on the powder particles F in contact with the wall surface of the powder container bottom plate 81. As the inclination angle of the transfer table is increased, the drop force increases, the powder particle-wall surface friction force decreases, and the powder particle F drops at an inclination angle where drop force> powder particle-wall surface friction force. Therefore, by creating a state where the friction force between the powder particles and the wall surface> the falling force> the friction force between the powder particles, a state in which a part of the powder is held on the wall surface of the powder container bottom plate 81, that is, in FIG. Can create a state.

  In order to create a state where the friction force between the powder particles and the wall surface> the drop force> the friction force between the powder particles, first, the friction force between the powder particles and the wall surface> the friction force between the powder particles at the same inclination angle. To. If the inclination angle is the same, the friction force between the powder particles is determined by the properties of the powder. Therefore, the friction force between the powder particles and the wall surface may be larger than the friction force between the powder particles. For example, in the case of a powder that does not easily cause friction with the wall surface, a material that easily generates friction with the powder is selected as the material of the powder conveyance table 81, and the powder particle is reduced by roughening the wall surface in contact with the powder. The frictional force between the wall surfaces can be increased. After creating a state where the friction force between the powder particles and the wall surface> the friction force between the powder particles at the same tilt angle, the friction force between the powder particles and the wall surface> drop force> powder is adjusted by adjusting the transport table tilt angle. It is easy to create a state of interparticle friction force. Therefore, as the friction force between the powder particles and the wall surface is larger than the friction force between the powder particles, the range of the inclination angle that can produce the state of FIG. 3 becomes wider.

For example, when # 400 sandpaper is pasted on the surface of the powder container bottom plate 81 in contact with the powder using alumina powder having an average primary particle size of 0.4 microns, the transport table tilt angle is 35 to 60 degrees. The powder could be separated and held within the range of 40 to 55 degrees, and more stable separation and holding was possible. When the same powder is used and the powder conveying table 81 is made of an aluminum plate having a surface roughness Ra of 0.17 microns, the powder can be supplied with an inclination angle α in the range of 32 to 42 degrees, which is more stable. The supply was possible in the range of 34 to 40 degrees. Furthermore, when the powder container bottom plate 81 is a stainless steel plate having a surface roughness Ra of 0.05 microns, the powder can be supplied in the range of the inclination angle α of 32 to 40 degrees, and more stable supply is possible. The range was -38 degrees.
In the case of powder that does not easily generate frictional force, the wall surface of the powder conveying table 81 that contacts the powder may be roughened by shot blasting. In the case of powder that easily generates frictional force or powder that has high adhesion to the wall surface, the wall surface in contact with the powder of the powder transfer table 81 is treated with fluorine, or the powder transfer table 81 itself is removed. You may manufacture with a fluororesin.

In the present powder supply method, since the powder is quantitatively supplied with almost no compressive force, the powder does not adhere to the apparatus, and aerosol can be generated at a stable concentration for a long time. Moreover, since powder is supplied almost without applying a compressive force, coarse powder particles are not produced. Furthermore, even if the coarse powder particles are mixed in the powder to be charged into the aerosol generator, there is an effect that the coarse powder particles are not supplied to the aerosolization unit. FIG. 9 is a schematic diagram showing the movement of mixed coarse powder particles. Due to its size, the coarse powder particles are subjected to a force in the dropping direction as the surrounding particles fall, and most of them are forcibly dropped. As a result, the coarse powder particles are not supplied to the aerosolization unit while being held on the wall surface of the powder conveyance table 81. Further, the coarse powder particles remaining inside the powder layer 89 are not supplied to the aerosolization unit because the third scraper scrapes only the surface layer.
Furthermore, in this powder supply method, vibration is applied to the powder transport table by an air cylinder 88 serving as a vibration means. Even if the powder 79 does not fall sufficiently due to some trouble and a lot of powder remains on the powder transport table, the drop is promoted by this vibration, so a large amount of powder is supplied to the aerosol generation unit The aerosol can be generated at a stable concentration without being generated. In this embodiment, vibration in the Y-axis direction is generated using an air cylinder as the vibration means, but vibration is generated by rotating an electromagnet, vibrator using air or an unbalanced object with a motor. The direction of vibration is not limited to the Y-axis direction.

Next, operation | movement of the aerosol-ized part 87 is demonstrated using FIG. FIG. 5 is a cross-sectional view of the aerosol-generating part 87 shown in FIG. The aerosolization unit 87 includes a gas introduction pipe 91 serving as a gas introduction part and an aerosol lead-out pipe 92 serving as an aerosol lead-out part. One end of the gas introduction pipe 91 is connected to the transport pipe 52 and the gas cylinder 51 via a joint disposed on the vacuum vessel top plate 72, and the gas introduction port 91, which is the other end, is connected to the aerosol delivery pipe 81 near the powder transport table 81. It is bent in 92 directions. The aerosol lead-out port, which is one end of the aerosol lead-out pipe 92, is connected to the third scraper, and the other end is connected to the transport pipe 52 and the nozzle 55 via a joint disposed on the vacuum vessel top plate 72.
The powder held on the wall surface of the transfer table 81, scraped out by the third scraper, and supplied to the aerosol generating unit 87 is pulverized and crushed by the impact of the gas ejected from the gas inlet 91 to generate an aerosol generating unit. It is aerosolized in 93. The generated aerosol is sucked out from the aerosol lead-out pipe 93 and sprayed onto the base material 56 at a high speed in the structure forming chamber 54 via the transport pipe 52 and the nozzle 55. In the present embodiment, the powder supply amount per unit time can be arbitrarily changed by changing the rotation speed of the powder conveyance table 81, and as a result, the aerosol concentration can be arbitrarily changed. Further, by arbitrarily setting the height of the third scraper 86, the scraping amount of the powder can be controlled and the aerosol concentration can be adjusted.
In addition, since the aerosol generating part 87 is being fixed to the vacuum vessel top plate 72, even if it rotates the powder container 80, it does not move.

FIG. 6 is a cross-sectional view of another form of the aerosol-generating part 87 shown in FIG. The aerosolization unit 87 includes a gas introduction pipe 91 serving as a gas introduction part and an aerosol lead-out pipe 92 serving as an aerosol lead-out part. The gas introduction pipe 91 and the aerosol lead-out pipe are concentric double pipes, and one end of the gas introduction pipe 91 is connected to the transport pipe 52 and the gas cylinder 51 through a joint disposed on the vacuum vessel top plate 72. Yes. The aerosol lead-out port, which is one end of the aerosol lead-out pipe 92, is disposed above the third scraper, and the other end is connected to the transport pipe 52 and the nozzle 55 via a joint disposed on the vacuum vessel top plate 72. The gas introduction pipe 91 and the aerosol lead-out pipe 92 are branched outside the aerosol container, the gas introduction pipe is bent from the middle and connected to the gas cylinder, and the aerosol lead-out pipe is connected to the nozzle 55 without being bent as much as possible.
The powder is held on the wall surface of the transfer table 81, scraped out by the third scraper, and the powder supplied to the aerosol generating unit 87 is impacted by the gas ejected from the gas inlet 91 disposed so as to surround the scraper. Then, it is pulverized and crushed and is aerosolized by the aerosol generator 93. The generated aerosol is sucked out from the aerosol lead-out pipe 93 and sprayed onto the base material 56 at a high speed in the structure forming chamber 54 via the transport pipe 52 and the nozzle 55. In the present embodiment, the powder supply amount per unit time can be arbitrarily changed by changing the rotation speed of the powder conveyance table 81, and as a result, the aerosol concentration can be arbitrarily changed. Further, by arbitrarily setting the height of the third scraper 86, the scraping amount of the powder can be controlled and the aerosol concentration can be adjusted.
In addition, since the aerosol generating part 87 is being fixed to the vacuum vessel top plate 72, even if it rotates the powder container 80, it does not move.

Next, the configuration of another form of the aerosol generator according to the present invention will be described. FIG. 9 is an external view of an aerosol generator according to another embodiment of the present invention. The vacuum vessel 71 has a shape such as a rectangular parallelepiped. A vacuum container is provided with a powder storage part 81 for storing powder and a circulation belt type transfer means 90, and an inclination is provided in the powder feed direction of the transfer means, and the inclination angle α (see the side view of FIG. 10). ) Can be fixed at an arbitrary angle by a mechanism (not shown). Further, on the circulating belt type conveying means 90, the powder is formed into a fixed shape on one end or both ends of the first scraper 84 for forming a powder layer having a substantially uniform thickness and the powder layer. A second scraper 85 to be arranged, a third scraper 86 for supplying a powder layer formed by the first scraper 84 and the second scraper 85 to a tube that leads to an aerosol generation unit, and the powder in the gas And an aerosol-generating part 87 for dispersion. Further, in this powder supply method, vibration is applied to the circulation belt type conveying means 90 by the air cylinder 88 serving as the vibration means. Even if the powder 79 does not fall sufficiently due to some trouble and a lot of powder remains on the powder transport table, the drop is promoted by this vibration, so a large amount of powder is supplied to the aerosol generation unit The aerosol can be generated at a stable concentration without being generated. In this embodiment, vibration in the Y-axis direction is generated using an air cylinder as the vibration means, but vibration is generated by rotating an electromagnet, vibrator using air or an unbalanced object with a motor. The direction of vibration is not limited to the Y-axis direction. Further, there may be a case where a plurality of vibration means 88 are installed.
In this embodiment, since the amount of powder transported is almost constant at any part of the transported powder, a large number of third scrapers are installed and aerosols by making the belt width of the transport means sufficiently wider than the precision scraper. It is possible to supply powder to the generation unit, and it is possible to set a plurality of aerosol outlets from one transport means. For example, in the figure, a third scraper is set at both ends, but a plurality of third scrapers are fixed to the upper part of the vacuum vessel 71 and arranged in a horizontal direction perpendicular to the powder conveying direction to generate aerosol. It is also possible.

FIG. 11 shows an embodiment in which a powder replenishing means is provided. Since the powder 79 decreases as the aerosol is generated, a powder replenishing means for additionally replenishing the powder in the powder container 80 is provided. This eliminates the need to increase the size of the powder container 80 serving as a powder container in order to input a large amount of powder in advance, so that the aerosol generator can be reduced in size and is required for the rotating means. Power can be reduced. In addition, when the aerosol generator is used in a reduced pressure / pressurized environment, it is particularly effective because it is not necessary to stop the apparatus in order to replenish powder. Furthermore, even in the case of powder whose properties are likely to change due to friction with the rotating powder container 80, it is advantageous to add it little by little by the powder replenishing means because the influence of friction is reduced.

  By using the aerosol generator of the present invention or a device equipped with the aerosol generator, a structure made of a constituent material of fine particles such as a brittle material is directly formed on a substrate such as metal, glass, ceramics, or plastic, and in particular heating The structure can be formed at room temperature that does not require any means, and a structure having mechanical strength equivalent to that of the fired body can be obtained, so it can be used for the manufacture of structures with various protective films and functional films. it can.

It is the figure which showed the general structure of the composite structure preparation apparatus used conventionally. It is an external view of an example of the aerosol generator by this invention. It is an external appearance model figure of an example (rotary type) of the aerosol generator by this invention. It is an external appearance model figure of an example (rotary type) of the aerosol generator by this invention. It is one of the examples of an aerosol-ized part. It is one of the examples of an aerosol-ized part. It is DD cross section of the G section in FIG. It is a schematic diagram showing the motion of the mixed powder compact particle. It is an external appearance model figure of an example (belt) of the aerosol generator by this invention. It is a side model figure of an example (belt) of an aerosol generator by the present invention. It is an Example in the case of supplying powder by rotation of a powder supply part. It is the figure which showed the structural example of the conventional patent.

Explanation of symbols

DESCRIPTION OF SYMBOLS 51 ... Gas cylinder 52 ... Conveying pipe 53 ... Aerosol generator 54 ... Structure formation chamber 55 ... Nozzle 56 ... Base material 57 ... Base material holder 58 ... Exhaust pump 61 ... Sensor device 62 ... Feedback control circuit 63 ... Wiring 71 ... Vacuum container 72 ... Vacuum container top plate 73 ... Vacuum container bottom plate 74 ... Vacuum container body 79 ... Powder 80 ... Powder container 81 ... Transfer table 82 ... Powder container 83 ... Shaft 84 ... First scraper 85 ... Second scraper 86 ... Third scraper 87 ... aerosolizing section 88 ... vibrating means 89 ... powder layer 90 ... circulating belt type conveying means 91 ... gas introduction pipe 92 ... aerosol outlet pipe 93 ... aerosol generating section

Claims (12)

An aerosol in which fine particles of a brittle material are dispersed in a gas is sprayed from a nozzle toward a base material, the aerosol is made to collide with the substrate surface, and the fine particles are crushed and deformed by the impact of the collision, and joined. An aerosol generator used in a composite structure manufacturing apparatus for forming a structure made of a constituent material of the fine particles on the base material,
The aerosol generating device contains a powder container for storing powder composed of fine particles of the brittle material;
Conveying means installed in the powder container and disposed so that a part of the powder comes into contact with the powder;
An aerosolization part for dispersing the powder in a gas;
Adjusting the shape of the powder on the conveying means, and a scraper part for guiding the powder to the aerosolization part;
The conveying means is inclined with respect to the direction of gravity, and a part of the powder is conveyed by the conveying means in a direction against gravity, and the held powder is passed through the scraper portion to the aerosol. An aerosol generation device, characterized in that the aerosol generation device is supplied to a gasification unit. An aerosol in which fine particles of a brittle material are dispersed in a gas is sprayed from a nozzle toward a base material, the aerosol is made to collide with the substrate surface, and the fine particles are crushed and deformed by the impact of the collision, and joined. An aerosol generator used in a composite structure manufacturing apparatus for forming a structure made of a constituent material of the fine particles on the base material,
The aerosol generating device contains a powder container for storing powder composed of fine particles of the brittle material;
A powder supply unit arranged so that a part thereof is in contact with the powder stored in the powder storage unit;
A rotating means for rotating the powder supply unit around an axis;
An aerosolization part for dispersing the powder in a gas;
Adjusting the shape of the powder on the rotating means, and a scraper part for guiding the powder to the aerosolization part;
A rotating shaft of the rotating means is inclined with respect to the direction of gravity, and a part of the powder is conveyed in a direction against gravity by rotation of the powder supply unit, and the held powder Is supplied to the aerosol generating unit through the scraper unit.   The aerosol generating apparatus according to claim 1, wherein the conveying unit is a circulation belt.   A first scraper that causes the scraper portion to form a powder layer having a substantially uniform thickness; a second scraper that adjusts a widthwise end of the powder layer; the first scraper; and the second scraper; The aerosol generator according to any one of claims 1 to 3, further comprising a third scraper for supplying a part of the powder of the powder layer formed by the step to the aerosol generating unit. .   In the aerosol generating apparatus, the retention of the powder in the previous period is due to the frictional force between the wall surface of the powder supply unit and the powder, the frictional force between the powders, van der Waals force, or static electricity. The aerosol generator according to any one of claims 1 to 3.   In the aerosol generating apparatus, the aerosol generating unit is configured by at least a gas introducing unit and an aerosol deriving unit, and the gas introduced from the gas introducing unit is sprayed onto the powder supplied from the third scraper. The aerosol generator according to claim 1, wherein the aerosol generator is dispersed and led out from the aerosol lead-out unit.   The aerosol generating apparatus according to any one of claims 1 to 6, further comprising a vibrating means for applying vibration to a portion for holding the powder.   The aerosol generating apparatus according to claim 1, further comprising a powder replenishing unit that additionally replenishes the powder container with the powder.   The aerosol generator according to any one of claims 1 to 6, wherein the aerosol generator includes a heating mechanism at a portion where the powder comes into contact.   The aerosol generator according to any one of claims 1 to 6, wherein an ultrasonic vibrator is provided in the scraper portion in the aerosol generator.   The aerosol generating apparatus according to any one of 1 to 6, wherein a fine scraper portion can be positioned with respect to the powder conveying means by an actuator or the like in the aerosol generating apparatus. It is a composite structure preparation apparatus provided with the aerosol generator and the nozzle for spraying aerosol on a base material, Comprising: The aerosol generator according to any one of claims 1 to 11 is provided as an aerosol generator. Composite structure manufacturing equipment.

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