RU2183510C2 - Powder sprayer - Google Patents

Abstract

FIELD: mechanical engineering; atomizing and spraying device. SUBSTANCE: invention relates to device used for introduction of metered out amount of powder from filler funnel into air stream, particularly, to powder sprayer which can be connected with feed deagglomerator for delivering metered out amount of atomized powder into stream of air in form of cloud of moving particles. Proposed powder sprayer has cylindrical pan, cylindrical flexibly deformable member secured on shaft for rotation around axle inside pan. Pan is installed coaxially relative to member. Member and pan form Venturi cylindrical space to which powder is fed. Venturi space has inlet and outlet located along circumference. Special device is provided to rotate member inside pad at speeds exceeding the speed required for centrifuging powder from member. Member pumps ambient air through Venturi space atomizes and deagglomerates powder fed to inlet of Venturi space, thus forming homogeneous moving cloud of material particles, cloud being homogeneous both along and across said axis. Invention proposed combinations of sprayer with powder feeder and sprayer with powder feeder and deagglomerator which are useful when serving the problems of covering wide panels for production of cloud homogeneous both in cross and longitudinal directions relative to panel and with uniform distribution of particles within cloud and distribution of particles by size in continuously movable cloud. EFFECT: enlarged operating capabilities. 50 cl, 10 dwg

Description

 The present invention relates to a device used to introduce a metered amount of powder from a charge funnel into an air stream, in particular, more particularly, relates to a powder atomizer that can be connected to a supply deagglomerator to introduce a metered amount of atomized powder into the air stream in the form of a moving cloud particles.

 Previously, powders were sprayed in various ways. Fill funnels were used to supply powders into a moving air stream. However, the filling funnels were unsatisfactory for introducing the powder due to the binding of the powder or due to the presence of electrostatic forces that exist between the powder particles. Variables such as moisture, particle size, particle shape, density, tackiness of the material, chemical composition, charge funnel configuration, and electrostatic forces between powder particles could also affect flow rates. Additional problems arise when it is necessary to produce a very precisely defined amount of powder at constant instantaneous flow rates, and also when the sprayed powder tends to agglomerate.

 Therefore, it is highly desirable to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and deagglomeration devices. It is also highly desirable to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and de-agglomeration devices that are capable of introducing very accurately measured amounts of powder into a constant flow of air.

 Fill funnels, even equipped with vibrators, are well known for their irregularity in measuring out a strictly defined amount of powder when applied as a coating. Additional problems arise when covering wide objects, when they try to spray powder from a filling funnel in a flowing air stream, because the air stream used for atomization was more or less two-dimensional in the longitudinal and lateral directions. When covering wide canvases, this airflow is generally flat and has a relatively low speed. In this case, it does not have stresses due to the high local velocity gradients required for the deagglomeration of the supplied powder, and therefore, the cloud may include agglomerated particles of large sizes and powerful flows of variable concentrations of particles, which are undesirable in many processes. Therefore, it is highly desirable to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and de-agglomeration devices to cover wide canvases that can produce clouds of non-agglomerated particles of a relatively constant size, which are relatively uniform as in the transverse and in the longitudinal direction of the canvas.

 Recently, accurately measured amounts of powder material can be measured and introduced into the air flow, and also sprayed using feed devices such as those described in US Pat. No. 5,314,090, and the particle size in the cloud can be made more constant by using a deagglomerator such as described. US Pat. No. 5,035,364. Although the combination of such a supply device for a material and a deagglomerator is capable of producing uniform clouds of particles, both uniform in particle size and distribution, as well as in Rine and length cloud, the combination still does not produce uniform clouds of particulate material in wide web coating, in particular in powder coating roll sheet metal, as well as the coating of closely spaced objects on the conveyor. The combination of many devices for supplying material and deagglomerators close to each other produces a cloud that can be uniform in particle size in the direction along the stream. However, there is still heterogeneity in the transverse direction of the cloud due to overlap and layering. Therefore, it is highly desirable to develop an improved powder atomizer, a combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and deagglomeration devices capable of producing clouds from material particles that are relatively uniform in the longitudinal and transverse directions of the cloud and which contain particles of material with a relatively uniform particle size, relatively uniformly distributed inside the cloud over large areas, which, in particular, are found when covering wide canvases.

 Recently, accurate measurement of small amounts of powder can be carried out using the material feed device described in US Pat. No. 5,314,090, by using a long brush that has an axis length longer than the width of the sheet to be coated. When using such a device, accurately measured amounts of powder can be supplied, however, without spraying and complete deagglomeration. The canvases can be arranged horizontally and it is necessary to apply a coating on the top or bottom or on the top and bottom of the canvas, and can also be arranged vertically if necessary, coating on one or both sides. That is why it is necessary to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, as well as an improved combination of a powder atomizer, powder supply device and de-agglomeration for use in performing coatings arranged both horizontally and vertically that produce a cloud of particles, which is highly homogeneous in the transverse and longitudinal directions, as well as in particle size and in the distribution of particle sizes. It is also necessary to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and deagglomeration devices that can be used to direct a particle cloud that is uniform in both transverse and longitudinal directions, and by particle size and particle size distribution both on the upper side of the horizontal webs placed below the spray gun and on the lower side rizontalnyh webs placed above the atomizer or to the opposite side webs arranged vertically.

 In order to ensure uniformity and versatility, it is necessary to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, as well as an improved combination of a powder atomizer, powder supply device and de-agglomeration for such use in various applications at a reasonable price.

 Ultimately, it is necessary to develop an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and deagglomeration devices that have all of the previously mentioned features.

SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, and an improved combination of a powder atomizer with devices for supplying and deagglomerating the powder.

 It is also an object of the invention to provide an improved powder spray gun, an improved combination of a powder spray gun and a powder supply device, as well as an improved combination of a powder spray gun, powder supply and de-agglomeration devices that can introduce very accurately measured amounts of powder into continuously controlled air flows.

 It is also an object of the invention to provide an improved powder spray gun, an improved combination of a powder spray gun and a powder feed device, and an improved combination of a powder spray gun, powder feed and de-agglomeration devices for coating wide webs that can produce clouds of relatively constant de-agglomerated material particles in cross sections that are relatively constant in both the transverse and longitudinal directions of the web.

 It is also an object of the invention to produce an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, as well as an improved combination of a powder atomizer, powder supply and deagglomeration devices that are capable of producing clouds of particles that are substantially uniform in both the transverse and longitudinal directions, and in particle size, as well as in the distribution of particle sizes.

 It is also an object of the invention to provide an improved combination of a powder atomizer, devices for supplying powder and deagglomeration and an improved atomizer, as well as an improved deagglomerator for use in powder coating horizontal and vertical surfaces that produce a cloud of particles that is highly homogeneous both in the transverse and longitudinal directions, and by particle size, as well as by particle size distribution.

 It is also an object of the invention to provide an improved powder atomizer, an improved combination of a powder atomizer and a powder inlet device, and an improved combination of a powder atomizer, powder inlet and de-agglomeration devices that can be used to direct a particle cloud that is uniform in both transverse and longitudinal directions and the size of the particles, as well as the distribution of particle sizes as to the upper side of horizontal paintings located below the spray rer and a lower side of the horizontal webs disposed above the atomizer or combination, or to the opposite sides of vertically disposed webs or parts arranged vertically.

 It is also an object of the invention to provide an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, and an improved combination of a powder atomizer, powder supply and de-agglomeration devices for such applications in various applications at a reasonable price.

 Finally, it is an object of the invention to provide an improved powder atomizer, an improved combination of a powder atomizer and a powder supply device, as well as an improved combination of a powder atomizer, powder supply and de-agglomeration devices that have all of the above features.

 In a broader aspect, the invention provides an improved powder atomizer comprising a cylindrical pan, a cylindrically elastically deformable element mounted on a shaft for rotation about an axis within the pan. The pallet is mounted coaxially with this element. The element and the pallet form a cylindrical Venturi cavity between them, into which the powder is supplied. The venturi has an inlet and an outlet radially remote from each other. Means are used to rotate the element within the pallet at speeds exceeding the speeds necessary to separate the powder from the element by centrifugal forces. The element creates a stream of ambient air through the venturi and sprays and destroys the agglomerates of the powder supplied to the inlet of the venturi, thereby forming a uniformly moving cloud of material particles, which is uniform both along and across the specified axis. The invention also includes a spray gun with a feed device and a combination of a spray gun with a device for powder deagglomeration and its feed, which is described in US Pat. , and by the distribution of particles and the size of the particles inside a homogeneous flow cloud.

 These tasks are solved with the help of signs of independent claims 1, 2, 31 and dependent claims 3-30, 32-50.

Brief Description of the Drawings
The above and other features and objects of the invention and the method of achieving them will become more apparent and the invention itself will become more clear when using the links to the subsequent description of one of the embodiments of the invention together with the accompanying drawings, in which:
FIG. 1 is a general and fragmentary view of the improved inventive atomizer mounted under a conventional filling funnel for use in powder coating the upper surface of a wide web, one end being removed to facilitate viewing of the device;
FIG. 2 is a cross-sectional view of the device shown in FIG. 1 along a section line 2-2 in FIG. 1;
figure 3 is a General and fragmentary view of the invented improved atomizer, as in figure 1, mounted under a standard feed filling funnel device for powder coating the lower surface of a wide web;
FIG. 4 is a cross-sectional view of the device of FIG. 3, constructed substantially along section line 4-4 of FIG. 3;
FIG. 5 is a general and fragmentary view of the improved inventive atomizer, as in FIGS. 1 and 3, mounted under a powder supply device, such as described in US Pat. ;
Fig.6 is a General and fragmentary view, as in Fig.1, 3 and 5, of a device similar to that shown in Fig.5, for covering the right side of the same canvas;
FIG. 7 is a plane view of a spray gun and a powder supply device similar to that shown in FIG. 5 for coating substantially vertically arranged and generally horizontally movable coating substrates in which the powder spray gun is angled with respect to the substrate, the powder chute divided into segments, and the wing is mainly cylindrical in shape;
FIG. 8 is a view of the device as in FIG. 7, but for another embodiment of the atomizer and powder delivery device shown in FIGS. 5-7, in which the powder atomizer is mainly horizontal and the substrate is mainly vertical and moves mostly horizontally and the wing is raised in a spiral upward from the atomizer;
FIG. 9 is a fragmentary and general view of a spray gun and a wing detached from the device shown in FIG. 8; and
FIG. 10 is a fragmentary cross section as in FIG. 2, another embodiment of a spray gun installed for use in the process of applying the powder to the upper surface, with one end removed to improve the visibility of the device.

Description of a specific embodiment of the invention
In FIG. 1 and 2, a powder sprayer 10 is shown as part of the equipment 12 for coating powder of wide canvases, mounted above a substrate 14 of a wide fabric for coating the upper side 16 of the substrate 14. The equipment 12 includes a device for supplying powder 18 and a sprayer 10. Device for supplying the powder is shown as a normal filling funnel 20, which can be equipped with a vibrator 22 if necessary. The filling funnel 20 has an open slot 24 below, through which the powder falls on the atomizer 10 below it. In other implementations, the powder dispenser 18 may be an elongated dispenser, such as described in US Pat. No. 5,134,090, shown in FIGS. 5 and 6, and which will be described in detail below. The full disclosure of US Pat. No. 5,341,090 is incorporated herein by reference.

 The spray gun 10 shown includes a pan 26, a wing 50, and a cylindrical spray element 28 mounted on pins for rotation about a horizontal axis 30 in the direction of arrow 31. The pan 26 also has a cylindrical shape. The pallet 26 and the element 28 are mounted coaxially with respect to each other. The pallet 26 partially covers the element 28. The element 28 and the pallet 26 are removed from each other so that a cylindrical venturi 32 is formed between them, into which the powder is supplied from the feeder 18. The venturi 32 has an inlet directly below the open slot 24 of the feeder 18. The venturi 32 also has an outlet 38 radially distant from the nozzle inlet 34.

 The wing 50 is mounted flush with the brush 28 and extends from the outlet of the venturi 38 in the direction of the region where the cloud of agglomerated particles should be directed.

 The filling funnel 20, the tray 26, the spray element 28, the venturi 32, the inlet 34, the outlet 38 and the wing 50 can be extended so as to extend beyond the entire width of the transverse dimension of the substrate 14, whatever its transverse dimension. In specific implementations, this lateral dimension was more than 6 feet (1.8 m). There are no known reasons why this transverse dimension in specific implementations could not be tens of meters or correspond to the transverse dimension of the largest substrates to be processed.

 The spray element 28 is connected to the motor shaft 40 via a transmission 42 and connected to the motor 44. The motor 44 and the transmission 42 rotate the shaft 40 and the element 28 in the direction of arrow 31 at a speed exceeding the speed necessary to discard the powder from the element by centrifugal forces. The speed of element 28 carries air through the venturi with a rather significant increase in speed, sufficient for introducing the powder into the air stream, for mixing air and powder into a homogeneous mixture and for breaking down particle agglomerates due to particle collisions with the brush bristles and the wall and particle formation is relatively identical size.

 The speed of element 28 can also charge particles of the resulting homogeneous cloud, with each particle having the same charge. By selecting the non-conductive material of the bristles of the element 28 and the non-conductive material of the particles, a charge of the same polarity can be imparted to each particle of the cloud of particles at the time it leaves the atomizer. This process is commonly known as the triboelectric effect. The charge located on the particles is useful because it helps disperse the particles of a uniform cloud in both its longitudinal and transverse directions at the time it leaves the atomizer. This charge also increases the area within which the cloud is completely uniform in particle size distribution, particle size and particle density.

 This triboelectric effect also has its drawbacks when the pallet 26 and the wing 50 are made of conductive materials, since the electric charge of the particles induces an opposite electric charge on the pallet 26 and the wing 50 such that the particle is attracted to the pallet 26 and the wing 50 and simultaneously form on them particle agglomerates. Depending on the conductivity of the material of the particles, the particles can accumulate and agglomerate on the edge 91 of the pallet 26 or wing 50 to such an extent that the agglomerated material of the particles can fall from the edge 91 onto the coated substrate below. Generally speaking, such agglomeration cannot be allowed when coating the upper surface of the web, since this particle material that agglomerates will fall earlier or later on the surface to be coated, causing damage to the surface to be coated.

 Agglomeration at the edge 91 can be minimized by manufacturing a pallet 26 and a wing 50 of non-conductive material. However, sometimes the pallet 26 and the wing 50 are preferably made of a conductive material, as will be mentioned later.

 In the specific embodiment illustrated in FIGS. 1 and 2, the pallet 26 and wing 50 are made of non-conductive material. In specific examples, this non-conductive material may be polycarbonate, acrylic, or acetate. In this particular implementation, the powder did not agglomerate on it, and the pan 26 and wing 50 were not charged by induction to such an extent that agglomeration of the powder appeared on it. Experiments show that any material having a conductivity in the range from 10 to 10 degrees to 10 to 16 degrees, in the framework of the invention can be considered as non-conductive.

 In other specific embodiments, such as those shown in FIGS. 1 and 2, the pallet 26 and wing 50 are made of conductive materials such as metal, since strength of both the pallet 26 and surfaces 93, 94 is required. In some implementations, the surface 93 has no bumps and is polished to a standard deviation of 125. Similarly, the surface of the wing 94 is polished to a standard deviation of 125.

 In a specific embodiment, as illustrated in FIG. 10, the tray 26 in the main body is made of a conductive metal, such as stainless steel, for strength and longer life, and the edge 91 is made of a non-conductive material such as polycarbonate, acrylic, acetate or polyethylene, since the structural strength is provided by the metal of the main part 95. Thus, the pallet 26 has a conductive part 95 and a non-conductive part 96. The non-conductive part 96 extends from the edge 91 to at least the lowest point 98 on the pallet 26, as azano. Parts 95, 96 may be joined together by any of known methods. Figure 10 shows parts of the pallet 95 and 96 connected by tongues and recesses 99 so that the part 96 of the pallet can be inserted into the end part of the part 94 of the pallet before alignment. In this way, the surface 92 of the pallet 26 can be made continuous. In some implementations, surface 92 is polished to a standard deviation of 125.

The wing 50 has an aerodynamic surface 94 located outward from the element 28, a surface 104 located at its end in close proximity to the element 28, and a rear surface 106. As shown in FIGS. 1 and 10, the aerodynamic surface 94 may be curved or flat. The surface 94 is directly adjacent to the element 28 and extends outward from the element 28 so as to direct the cloud outward from the cloud emerging from the outlet 38 of the venturi. The end 104 may be flat or curved, as shown in FIGS. 1 and 10. In FIG. 10, the end surface 104 is curved with a radius slightly larger than the radius of the element 28 and cylindrical in shape. Both the rear surface 106 and the opposite end surface 102 may be flat or curved, as desired. In the specific embodiment shown in FIG. 10, each of these surfaces is flat and has a slope angle designed to prevent the collection of powder on it, and also to direct the powder collected on it from the surface to be coated. The powder is prevented from accumulating on the surface 94 both due to the absence of an induced electric charge and due to the speed of the air flow moving through the surface 94. On the other hand, the end surface 102 has a small stream of air moving through its surface. Thus, in most implementations, the surface 102 has an angle with respect to the horizontal in the range from 80 to 100 ^° . In most cases, the angle of repose of the powder is 80 ^o . The rear surface 106, like the surface 102, has a small flow of air to the surface. Thus, the surface 106 will collect powder on itself if the angle of repose is not maximized. However, the powder accumulating on the rear surface 106, if it has an angle with respect to the horizontal greater than the slope angle of the powder, will always return after it has accumulated on the surface by falling onto the surface and onto the rotating element 28. In specific implementations, the surface 106 has an angle of relative to the horizontal from 45 to 70 ^o .

 In FIG. 1 and 2 show that surface 94 must be curved. Surface 102 extends from this curved surface perpendicular to the latter. The back surface 106 extends from the filling funnel 18 to the wing 50, having openings for return 110. FIG. 3, 4, 5, and 6, as shown, have a similar surface 94, rear surfaces 106, and perpendicular surfaces 78. Return holes 110 are located on surface 78, as shown.

 Element 28 functions both as a blower in conjunction with a tray 26 to direct air and powder entering it through the venturi 32, and as a powder carrier, as described in US Pat. No. 5,314,090.

 The rotational speed of the element 28 and the removal of the element 28 from the pallet are connected so that the required air passing through the venturi 28 has a sufficiently high speed for spraying the powder entering the inlet of the venturi 34, and also that the powder is uniformly atomized in the form of a cloud emerging from the outlet of the venturi 38. In typical embodiments, the outlet of the nebulizer 28 is a brush, such as is described in US Pat. No. 5,314,090.

 The brush 28 may be any cylindrical element that has a core and radially spaced bristles of any type. The bristles can be located tightly or removed from each other, placed orderly or randomly, long or short, thin or thick, relatively hard or relatively flexible and made of materials in the range from metals to plastics and natural threads. The diametral size of the core and the length of the bristles can also vary. The choice of bristles depends on the functions of the brush and the type of powder sprayed.

 If a sprayer is used to spray large quantities of powder into a small amount of air, then the brush should carry some powder between the bristles before spraying. In this case, the length of the bristles should be longer than usual in order to increase the amount of powder carried between the bristles by the brush.

 If the powder used tends to agglomerate or has difficulty moving it in the atomizer, then flexible bristles have the advantage of being flexible because the bristles facilitate the movement and deagglomeration of the powder.

 If it is desired to reduce particle size, then a stiff bristle brush is required. The length and material of the bristles will determine the duration of the brush in each particular application.

 The magnitude of the charge of individual particles from the cloud of particles leaving the atomizer 10 generally increases with increasing rotation speed of the element 28, with a decrease in the conductivity of the material of the bristles and with a decrease in the conductivity of the material of the particles. In most applications, the design of the brush element 28 can also be changed and ultimately controlled by changing the rotation speed of the spray element 28. In typical versions where deagglomeration and particle size reduction are required, a brush with bristles made of special materials having a certain transverse diameter and a certain diameter is selected longitudinal length. The bristles can be round or square in cross section. If they are square in cross section, then the elastic flexibility of the bristles in the direction of rotation and in the direction transverse to it may differ. This is important, since both agglomeration and particle size reduction are believed to depend on collisions of particles with the bristles, in which the bristle acts on the particle and then moves to the side perpendicular to the direction of motion, making it possible for the particle to collide with another bristle. Thus, the denser the bristles are located, the more collisions of the bristles with particles occur. The ratio of the length to the transverse dimension in the direction of rotation and the rotation speed of the brush determine the collision force between the particle and the bristle. The ratio of length to size across the direction of rotation and the density of the bristles, as well as the rotational speed of the brush, determine the number of collisions that will occur between particles and bristles.

 In typical embodiments, the bristles may include natural bristles, synthetic polymer bristles, and metal bristles. The length of the bristles varies from relatively short to extremely long. The transverse size of the bristles can exceed the size of the sprayed particles, both 2-3 times and 50 times, with respect to the largest particles. In practice, the bristles have a limit on the maximum transverse size from 4 to 15,000 microns and a length from a few centimeters to several meters.

 While the influence of the ratio of the longitudinal length to the transverse size of the bristles on the decrease in particle size and the ability to deagglomerate the element 28 is very noticeable, it seems that the total diameter of the brush 28 has a smaller effect on the deagglomeration and decrease in particle size. When selecting element 28 with a larger diameter, the longitudinal length of the venturi increases in the direction of air flow and, thus, the number of collisions between particles and bristles increases. However, the collision force between the bristles and particles is determined by the hardness of the bristles and the aforementioned ratio of the longitudinal length and the transverse size of the bristles. Thus, increasing the diameter of the element 28 and maintaining the same ratio of length to the transverse size of the bristles simply increases the number of particle collisions, and not the type of collisions that occur. Thus, the main thing in most applications is the ratio of the length to the transverse size of the bristles and the properties of the bristle material, and not the diameter of the brush 28.

 However, in typical implementations, the ratio of length to transverse size of the bristles varies from 200 to one to about 800 to one, the length of the bristles varies from about half an inch (1.25 cm) to 5 inches (12.5 cm). The transverse dimensions of the bristles in the direction of rotation vary from about 0.001 (0.002 cm) to 0.062 inches (0.155 cm), the transverse dimensions of the bristles in the direction transverse to the direction of rotation, vary from about 0.001 (0.002 cm) to 0.062 inches (0.155 cm) and the ratio of bristle length to transverse size varies from about 200 to one to 800 to one.

 In some implementations, the pallet 26, the element 28 and the wing 50 may be extended for coating processes of wide webs or may have a length to diameter ratio of the element 28 of less than 1, if necessary. In some implementations, the thickness of the venturi or the distance between the element 28 and the pan 26 is comprised between about 0.001 (0.002 cm) and 0.100 inches (0.25 cm), and the element 28 rotates at a speed of about 700 to 4000 rpm depending on the diametric rotor size and intensity in pounds per minute at which it is desirable to spray the powder with the inventive improved atomizer. Additionally, in these implementations, the element 28 is removed from the ends of the pallet, which are removed from the drawings for clarity of the rotor element 28 and the venturi 32, and removed from the wing 50 at a distance of from about 0.001 (0.002 cm) to 0.020 inches (0.05 cm). In these representative implementations, a powder having a particle size of from about 2 to 300 microns can be atomized as a uniform cloud of material particles having a relatively constant particle size uniformly distributed in the cloud both in the flow direction and in its transverse direction.

 As the charge funnel 20, any standard charge funnel designed for use with powder material can be used. The filling funnel may be symmetrical, as shown in FIGS. 1 and 2, or may be asymmetric, having, for example, a vertical wall and a wall located at an angle to both vertical and horizontal. It is desirable that both walls of the filling funnel have an angle with respect to the horizon greater than the slope angle of both the material of the walls of the filling funnel and the supplied powder material. The filling funnel is installed independently of the powder atomizer 10 and can be mounted on a spring suspension (not shown) and equipped with a vibrator 22, as mentioned earlier.

 The bottom opening 24 of the charge funnel, as shown, is located above the inlet 32 of the venturi. The inlet of the Venturi cavity 32 in a particular implementation may be convergent in order to capture all the powder falling from the charge funnel 20 into the atomizer 10. The outlet 38 of the Venturi cavity 32 and the wing 50 are directed and necessary to supply a stream of particle material uniformly atomized in the volume air into the inlet region 46 of the standard electrostatic coating device 48. The direction of the cloud to the target is accompanied by the use of wing 50 and methods based on the Coanda effect for gas flow. The wing 50 may serve to block the top of the spray element so as to maintain an atmosphere around the spray with the lowest possible dust content.

Surprisingly, the cloud leaving the vent hole of the venturi 38 is not discarded from the rapidly rotating element 28, as might be expected. On the contrary, it turns out that a uniform cloud of suspended material particles follows the arched surface of the element 28 in a circle around the element by at least 90 ^o and even 360 ^o . Therefore, you need a wing that removes and holds the cloud from following element 28.

 The purpose of the wing is not only to remove the cloud from element 28, but also to direct the cloud, as needed, to the desired area. Thus, in all implementations, the leading edge of the wing should actually be adjacent to the periphery of the element 28. From experience, it turns out that the element 28 functions well if it is placed as close to the brush as possible.

 It is completely surprising in the operation of the atomizer 10 that the area between the powder atomizer 10 and the coating device 48 does not have to be completely enclosed, since the cloud of particles exiting the Venturi cavity mainly follows, firstly, the arched path of rotation of the element 28 and then, secondly, the surfaces of the wing 94 and will not be sprayed in the space surrounding the sprayer under uncontrolled conditions, as is the case with powder sprayers of other designs. It turns out that the nebulizer 10 gives the cloud a significant speed so that the Coanda effect prevails over the effect on the cloud of particles, which has a substantially stationary ambient air.

 Once the cloud is directed into the input region 46 of the electrostatic coating device 48, the cloud is exposed to the electric ionization field of the electrodes 52 of the coating device and the gas flow moving the cloud through the coating device 48. In specific implementations, the coating device 48 may be any of as described in US Pat. No. 5,279,863, the contents of the description are incorporated herein by reference.

 In typical implementations, the wing 50 may be attached either to the charge funnel 20 and vibrate with it in order to minimize the accumulation of powder on it, or fixed independently or attached to the pallet 26.

 In FIG. 3 and 4 show a sprayer 10 and a device 12 for use in coating the lower surface 53 of the substrate 14. The device for supplying powder 18 is also made in the form of a filling funnel 20. In FIGS. 3 and 4, the filling funnel 20 is shown without a vibrator 22, but with a device for loading 54 located near the filling funnel 20 to maintain the filling funnel full of powder. Similarly, in other implementations, the device of FIGS. 1 and 2 can be equipped with a feed device 54 and can be used with or without a vibrator 22. The speed at which the feed device 54 operates must be interconnected with the speed of the sprayer 10 so that continuous and the corresponding flow of powder from the feeding device 54 through the filling funnel 20 and through the sprayer 10 into the coating device.

 In this implementation, the charging funnel 20 and the atomizer may be identical to those described previously. However, the wing 50 is placed close to the exit 38 so as to cover the gap between the pallet 26 and the inlet area 46 of the coating device. The wing 50 may be shaped and may be placed in accordance with conventional methods operating in gas streams. A cloud of material particles uniformly distributed in it is removed from the element 28 and fed to the input 46 of the coating device 48, as soon as the cloud is exposed to the electric field of the device 48, its movement in the device 48 is controlled by the discharge in the device and gravity, as usual.

 Surprisingly, only a small amount of powder was not deagglomerated when using a nebulizer to a particle size such that the powder was completely suspended in air. Almost all of the powder entering the atomizer 10 from the powder supply device 18 was completely de-agglomerated to the required particle size and atomized, and there was no powder not atomized in the air and discharged through the powder drain 56 at its lower edge. Therefore, it is assumed that in most cases, powder drainage 56, designed to remove large particles that cannot be suspended in the cloud leaving the sprayer 10, is not necessary, but is superfluous in the composition of the sprayer 10.

 In all embodiments, the substrate 14 is conveyed in a conveyor manner relative to the sprayer 10, the powder supply device 18 and the coating device 48. The direction of movement of the substrate, that is, whether the uncoated substrate moves from the sprayer 10 or to the sprayer 10, depends on the coating process. As with other electrostatic coating processes, it may be more desirable to expose the uncoated substrate to a more concentrated cloud emerging from the atomizer 10. In other coating processes, it may be advantageous to increase the concentration of powder in the cloud when moving the coated substrate to the atomizer.

 In general, the conductivity of the pan 20 and wing 50 does not matter in the implementation shown in FIGS. 3 and 4, since the shown implementations are adapted to cover the bottom surface of the substrate. Since all equipment is located below the surface to be coated, any drops of sinter from the device will not affect the surface coating.

 In FIG. 5 and 6, the charge funnel 20 is shown replaced by the powder supply device 60 described in US Pat. No. 5,314,090. As shown, the powder supply device 60 of this patent is capable of supplying repeated and accurately measured amounts of powder to the inventive atomizer 10. Thus, the device for powder supply 60 can be used when controlling the supply of powder to the sprayer is more critical to the process and when control is required better than possible using a filling funnel 20, as described earlier.

 The powder supply device 60 is powered by a filling funnel 62, which functions as a reservoir for the powder feeding device 60. The filling funnel 62 may in some implementation be identical to the filling funnel 20 and may be equipped or used with or without a vibrator 22 . As shown, the filling funnel 62 has a bottom opening 24 that opens into a casing 64, in which an elastically deformable element or brush 66 is fixed for pivots to rotate in the direction of arrow 67. The element 66 is attached to a shaft 68 that is inserted into opposite walls (not shown) the casing 64. One end of the shaft is connected to the motor with a variable speed of rotation 70. The casing 64 has an inner part 72, a lower part 74, an upper part 76 and a pair of side parts 78. The casing 64 completely covers the element 66.

 Element 66 is generally cylindrical. The casing 64 may be made of plastic or any other suitable non-conductive material. In other implementations, the casing 64 is made of transparent plastic or has a door for access to the casing 64 (not shown) so that during operation it is possible to observe and make adjustments. The element 66 is placed in the casing 64 so as to close the opening of the filling funnel 24.

 In most representative implementations, it is desirable that the element 66 be a brush having a plurality of bristles 80 placed with a constant density around the core 81 and extending radially from it. The bristles 80 may be natural threads or threads of any suitable material so that the brush 66 is able to keep the powder from falling from the filling funnel 20 through the lower hole 24. The bristles 80 should be of suitable length and size for the selected rotation speed, the brush 66 allows the powder from the filling the funnels 20 penetrate precisely between the bristles 80, be carried by the brush 66 during its rotation and pass in a measured amount through the outlet 82 in the lower part 74 to the inventive atomizer. As described in US Pat. No. 5,314,090, the speed at which the element 66 rotates is always lower than the centrifugal forces required to detach the powder material from the element 66.

 The flow rate of the powder through the charge funnel 20 through the outlet 82 depends, inter alia, on the speed at which the brush 66 rotates in the direction of the arrow 67, the diameter of the brush 66, the capacity of the powder in the brush 66 and the size of the hole 24. The capacity of the powder in the brush 66 depends on the length and density of the bristles 80. The flow rate of the powder from the filling funnel 20 through the supply device 60 contributes to the total speed of the powder to the atomizer 10.

The output 82 of the feeder 60 is located so that the powder at the outlet falls into the inlet 34
venturi cavities 32 in the same manner as previously described with respect to the placement of the lower opening 24 of the filling funnel 20, as shown in FIG. 1-4. As shown in FIGS. 5 and 6, the casing 64 may be provided with a pallet 26 and a wing 50 so that a common casing is formed for both the element 66 and the element 28. Such a casing would extend the pallet 26 upward until it engages with the charging funnel 62 of the device for supplying material 60 and a wing 50 for covering element 66 and forming, together with the pallet 26, both exits 34, 82 for separating elements 66, 28, and for the correct formation of inlet 34 and outlet 38 of the venturi 32.

 As in FIG. 5 and FIG. 6, the substrate 44 can move toward or away from the atomizer 10. Moreover, the outlet 38 of the atomizer 10 and the cloud of particle material can be directed downward using a deflector, as shown in FIG. 5 or 6, or up, if necessary. This choice usually depends on the particle size and particle size distribution in the cloud, and whether or not the effect of gravity on the displacement of large particles on the substrate is required or not.

 In general, the conductivity of the pan 20 and the wing 50 does not matter in the embodiment shown in FIGS. 5 and 6, since the above embodiment is adapted to cover vertically arranged substrates. Since all equipment is placed on one side of the surface to be coated, so that the agglomerates falling from the device will not affect the surface coating.

 In the variants presented in figures 1-6, there are differences in structure. Pallet 26 and element 28 may be of any diameter. The amount of powder that can be sprayed using the atomizer 10, the greater the larger the element 28 and the tray 26, the larger the venturi 32 and the greater the volume of air in which the powder can be sprayed.

 If a brush is used as element 28, then the length of the bristles becomes variable. However, since the brush 28 rotates at a speed greater than the speed at which the powder will leave the sprayer under the influence of centrifugal forces, the influence of the length of the bristles is not critical.

 However, the distance between the brush and the tray is critical and depends on the element 28 and its speed. In typical implementations, this distance varies from about 0.005 (0.012 cm) to 0.100 inches (0.25 cm). The element 28, rotating at a speed sufficient to detach the particles to be sprayed from the element 28 by centrifugal forces, should be able to supply sufficiently turbulent air to the Venturi cavity at the speed necessary to spray the powder in this air. So, the distance between the element 28 and the pallet 26 may be greater if the speed of the element 28 is greater, and vice versa. In specific examples, it is desirable that element 28 has a diameter of 2 inches (5 cm) or more and rotates at speeds of about 700 to 4000 rpm.

 The vertical distance between the bottom opening 24 of the filling funnel and the inlet of the venturi or inlet 34 may also vary. This can be any distance that the powder can fly if it is effectively fed into the venturi. In typical embodiments, this distance may vary from one inch (2.5 cm) to 6 feet (183 cm) or more.

The radial removal of the inlet 34 into the venturi and the outlet or exit 38 may also vary. In specific examples, this distance was from about 180 to 45 ^o . In the variants shown in FIGS. 5 and 6, in which the inventive atomizer 10 is connected to the material feeding device described in US Pat. No. 5,314,090, the ratio between the diameters of element 66 and element 28 can be any number, in most cases this ratio is equal to or greater units, respectively, the ratio of speeds is best maintained as high as possible. The distance between the axes of the elements 28 and 66, measured between the shafts, is usually only greater than one diameter, but somewhere can be from about a few inches (cm) to 6 feet (183 cm) or more.

 In all implementations of the invention, the powder exiting the venturi 32 follows the contour of the wing 50 and, with its help, is directed to the target. The powder passing through the venturi cavity is deagglomerated, atomized, and acquires a charge due to the triboelectric effect, if the bristles of the brush are non-conductive, so that when it leaves the venturi 32, it is charged, and each particle of the powder has the same charge. Thus, the powder exiting the venturi 32 is continuously sprayed across and along the substrate both by the action of a turbulent air stream in which the particles are sprayed and by the forces of repulsion of equally charged particles.

 A cloud of particles follows the curve formed by the wing 50 due to the speed of the cloud across the wing. In typical implementations in which a powder atomizer is located at a distance of about 4 (144 cm) to 6 feet (183 cm) from the substrate, it was found that a cloud of particles can be directed onto the substrate while maintaining uniformity, with a track width of about 2 (5 cm) up to 6 inches (15 cm), and it remains uniform in both the longitudinal and transverse directions of the substrate. Outside the outer boundaries of the wake, the degree of uniformity of the concentration of cloud particles sharply decreases. This trace in the implementations shown in FIGS. 1 and 2, where the particle cloud is directed toward the target below the atomizer, and where gravity acts on the particle cloud, directing the atomized particles to the target, which, as described earlier, is 2 (5 cm ) up to 6 inches (15 cm), can expand from 4 (10 cm) to 10 inches (25 cm). Similarly, when the force of attraction acting on a cloud of particles counteracts the movement of a cloud of particles exiting the venturi 32, as is the case in the implementations shown in FIGS. 3 and 4, the previously described trace is from 2 (5 cm) to 6 inches wide (15 cm) can be reduced in width to about 1-3 inches (2.5 cm-7.5 cm).

 In any case, due to this phenomenon, a problem arises when uniformly coating vertically arranged substrates located at a distance from the invented sprayer greater than 4 (10 cm) to 6 inches (15 cm). For example, with a uniform coating of a vertically arranged substrate with a height of 12 inches (30 cm) moving horizontally, using the inventive spray gun located close to its lower boundary, only the lower 4-6 inches (10-15 cm) of the substrate will be uniformly coated, and the offset there will be significantly less powder on the top 6 inches (15 cm) of the substrate than on the bottom 6 inches (15 cm) of the substrate.

 In FIG. 7 shows a combination of a spray gun and a powder feed device for coating substantially vertically arranged and horizontally movable substrates with transverse dimensions greater than about 2-4 inches (5-10 cm). As shown in FIG. 7, a powder supply device 60 having the full structure of the previously described powder supply device 60 is mounted higher than the substrate 84. The atomizer 10 located below the supply device 60 has an element 28 mounted further from the substrate and located at an angle both vertically and horizontally, as shown. The powder chute 86 passes from the bottom opening 82 to the inlet 34 of the venturi, through which the powder falls from the powder supply device 60 to the venturi 32, formed by a tray 26 surrounding the brush element 28. The wing 50 extends from the outlet 38 of the venturi toward the substrate 84. The wing 50 and the tray 26 and the element 28 are equally distant from the substrate 84 and have a distance between the vent hole of the venturi and the substrate in typical implementations 4-6 inches (10-15 cm) over the entire length of the nozzle 10.

 Since the powder feeder 60 and the sprayer 10 can be of any length, the variant shown in Fig. 7 can be used to cover vertically arranged and horizontally moved sheet materials or an array of parts suspended vertically and horizontally moved in any transverse dimension and height .

 In general, the degree of conductivity of the pan 20 and the wing 50 in the implementation shown in Fig.7 does not matter, since the shown implementation is intended for coating vertically arranged substrates. Since the equipment is placed on one side of the surface intended for coating, agglomerates falling out of the device will not affect the surface coating.

 In FIG. 8 and 9 show another embodiment of a spray gun, a powder supply device and a deagglomerator intended for use with vertically placed and horizontally moving substrates of the previously described type. In this implementation, the powder supply device 60 should be placed above the spray gun 10, the powder chute 86 passes between the outlet 82 of the powder supply device 60 and the inlet 34 of the venturi 32, and the spray gun is equipped with a wing 50 that has a spiral shape with a leading edge of 88 in the form of a spiral in order to remove a cloud of particles from the element 28, a cylindrical cross-section and in the form of a spiral, the rear edge 90, which along the entire length is placed at a distance of about 4 to 6 inches (10-15 cm) from the substrate to be coated th. This implementation is only useful for those substrates that have transverse dimensions or a vertical height less than the vertical height of the spiral wing 50 plus or minus from one to 6 inches (1-15 cm).

 In some implementations, the feeder 60 may be located above the substrate 84 or on one side of the substrate 84, the spray gun must always be placed close to the lower edge 92 of the substrate 84, and the spiral wing 50 should extend over the full vertical dimension of the substrate 84, as shown.

 In FIG. 9 shows a general view of the drip tray 26, brush element 28 and spiral wing 50 of the spray gun 10 shown in FIG. 8, in order to better show the shape of the wing 50 and its relative position with respect to the outlet 38 of the venturi and the inlet 34 of the venturi.

 The powder chute 86 shown in FIG. 7 should consist of segments and have remote and generally parallel and generally vertical walls. The gutter 86 shown in FIG. 8 should be non-segmented and should not have parts or walls between opposite ends. Such gutters are interchangeable and depend on the size of the substrate and the properties of the powder to be sprayed.

 In the general case, the degree of conductivity of the pan 20 and wing 50 does not matter in the implementation shown in Figs. 8 and 9, since the implementation is adapted to cover vertically arranged substrates. Since all equipment is located on one side of the surface to be coated, agglomerates falling out of the device will not affect the surface coating.

 In the process, the powder from the filling funnel 20 is fed through the lower hole 24 into the inlet 34 of the Venturi cavity 32 in the implementations shown in figures 1-4. The flow of powder into the venturi 32 can be controlled either by setting the desired size of the hole 24 or by controlling the operation of the vibrator 22. As soon as the powder enters the venturi 32, the element 28 carries the gas carrier through the venturi at a relatively high speed and turbulence. Element 28 sprays all the powder that comes into contact with this element, while element 28 rotates at a speed exceeding that required to expel the powder from it by centrifugal force. The particle size, depending on the particle material and the degree of hardness of the bristles 80 of the element 28, can also be reduced in the atomizer 10 by changing the brush speed, if necessary. The powder sprayed in the gas carrier in the form of a cloud exits the outlet 38 of the venturi. This cloud is generally uniform in the amount of powder per unit volume of the gas carrier, as well as in the distribution of particle sizes and in the distribution of particles both in the direction of the gas stream and in its transverse direction. Moreover, the particle size distribution is generally constant in the cloud if the degree of turbulence of the gas carrier inside the venturi is sufficient to agglomerate the powder. In any case, with an appropriate choice of the element velocity, the powder with a relatively constant size can be relatively uniformly distributed in the cloud, both in terms of particle density and in terms of particle size distribution.

 The powder used in the aspirator 10 has very little mechanical work done by element 28 or gravitational forces. When a powder supply device 60 is used with the aspirator 10, very accurately measured quantities of powder can be supplied to the aspirator 10. By controlling the flow of powder from the filling funnel 62 to the feed device using standard means and controlling the speed of the element 66, very accurately measured quantities of powder can be supplied to the aspirator 10. Vibration and gravity move the powder from the charge funnel 62 to the inside of the element 66, which transfers the powder to the exit 82, doing very little mechanical work on the powder. In typical embodiments, in which the element is a brush, the powder enters between the bristles 80, the brush rotates and frees the powder and directs it through the outlet 82. Therefore, choosing the degree of vibration (if vibrator 22 is used), the casing having an outlet 24 of a predetermined size, brush 66 and rotation speed, it is possible to feed very accurately measured amounts of powder into the invented aspirator 10.

 During the rotation of the element 66, this element is exposed to powder in the filling funnel 62 and is filled with powder between the bristles and rotates over the outlet 82, through which the element 66 discharges the powder carried by the element. As soon as the powder is discharged from the feeder 18 or 60 into the aspirator 10, the powder enters the venturi 32 through the inlet 34 of the venturi and is picked up by a rapidly moving gas carrier, which is pulled through the venturi by element 28. Element 28 throws all the powder into the gas carrier with using centrifugal force and moves the turbulent gas carrier through the venturi towards the exit 38 from the venturi. As soon as the powder leaves the venturi cavity outlet 38, a uniform cloud of particles follows the curve defined by element 28 until it is removed from element 28 by wing 50 and is guided by wing 50 in accordance with the usual laws of gas flow towards the entrance 46 of the coating device 48. As shown in FIG. 1 and 2, the cloud from exit 38 can be directed downward by the invented aspirator 10 to cover the upper side of the substrate. As shown in FIGS. 3 and 4, the aspirator 10 can direct a cloud of particles from the exit 38 of the venturi upward so as to cover the lower side of the substrate. The substrates can be coated on both sides, being oriented both horizontally and vertically, as shown in figures 1-4, 5 and 6 and 7-9, respectively.

 The performance of the powder sprayer 10 in all implementations is controlled by the rate of powder flow into the venturi 32 from the feed device 20 or 60. The particle density of the clouds created by the inventive sprayer 10 is a function of the amount of powder entering the sprayer 10 and the amount of gas carrier passing through the venturi . In most practical applications, the amount of gas carrier passing through the venturi is controlled by the distance between the tray 26 and the element 28 and the rotational speed of the element 28. The smaller the distance, the smaller the gas carrier, the greater the distance, the greater the gas carrier. Similarly, the amount of powder entering the venturi from the feeder is primarily a function, in the case of a charging funnel 20, the size of the lower hole 24 and the flow of powder through it or, in the case of the feeder 60, the speed and capacity of the element 66.

 The atomizer produces a relatively uniform cloud of particle material and directs the cloud to the electrostatic coating device in an upward or downward direction, as necessary. The invention provides an improved powder sprayer and an improved combination of a sprayer with a feed device and an improved combination of a sprayer with a feed device and with a deagglomerator for all powder coating operations.

 In particular, a sprayer is needed to cover wide canvases, since it can produce clouds of particle material of a relatively constant size in cross sections both along and across the web, which can be highly uniform in both particle size and particle size distribution. Using a particle feed device, such as that shown in US Pat. to it, very accurately measured amounts of particle material.

 A powder spray gun, a combination of a powder spray gun with a powder feed device and a spray gun with a powder feed and deagglomeration device can be used to coat both the upper and lower sides of horizontally located paintings and both sides of vertically arranged paintings. A powder spray gun, a spray gun with a powder feed device, and a spray gun with a powder feed and deagglomeration device can be used to power the powder coating equipment at a reasonable cost for installation and maintenance.

 Ultimately, a sprayer, a sprayer with a device for supplying powder and a sprayer with a device for feeding and deagglomeration of powder can be created in a form that ensures the implementation of all the previously mentioned features.

 Since a typical implementation of the invention is shown and described here for illustrative purposes, the protection afforded by any patent that may be granted on this application is not limited to the described example, but applies to all structures and devices that fall within the scope of the formula attached to the present description.

Claims (50)

 1. A powder atomizer comprising a tray and a cylindrical element, the cylindrical element being mounted on a shaft for rotation about its axis, the pan is cylindrical and placed coaxially with the element, the pan partially surrounds the element, and the latter and the pan are installed to form a cylindrical venturi into which the powder is supplied, the Venturi cavity having an inlet and an outlet that are spaced apart from each other, means for rotating the element inside the pallet with growths exceeding the speeds required for dropping the powder from the element by centrifugal force, while the element is configured to supply gas through the Venturi cavity and spray the powder entering the inlet to produce a uniform cloud of material particles, and the powder atomizer is equipped with means to minimize electric charge by the pan and the resulting agglomeration of the powder at the outlet.  2. A powder sprayer including a tray and a cylindrical element, the cylindrical element being mounted on the shaft for rotation around its axis, the pan is cylindrical and placed coaxially with the element, the pan partially surrounds the element, and the last and the pallet are installed to form a cylindrical Venturi cavity wherein powder is supplied, wherein the Venturi cavity has an inlet and an outlet that are spaced apart from each other, means for rotating the element inside the pan with growths exceeding the speeds required for dropping the powder from the element by centrifugal force, while the element is capable of supplying gas through the Venturi cavity and spraying the powder entering the inlet to produce a uniform cloud of material particles, the tray adjacent to the outlet being made of non-conductive material. 3. The atomizer according to claim 2, wherein the non-conductive material has a conductivity of about 10 ¹⁰ - 10 ¹⁶ Ohm / cm.  4. The atomizer according to claim 2, wherein the non-conductive material is selected from the group of materials consisting of structural polymer materials.  5. The atomizer according to claim 2, wherein the non-conductive material is selected from the group of structural polymer materials consisting of polycarbonates, acrylics, acetals, and polyethylene.  6. The sprayer according to claim 2, wherein the sump adjacent to the outlet is tapered to form an edge adjacent to the member, the sump having a surface dependent on the edge.  7. The sprayer according to claim 6, in which the surface, depending on the edge, is perpendicular.  8. The atomizer according to claim 2, wherein the sump is made of non-conductive material from the outlet to at least the lowest point of the venturi.  9. The sprayer according to claim 1 or 2, in which the wing is made, remote from the element by a distance of approximately 0.002-0.05 cm, the wing having a surface extending from the element upward outward from the element, the surface being aerodynamically smooth and has an angle of with respect to the horizontal, the wing has an end surface remote from the element having an angle with respect to the horizontal surface greater than the angle of repose, the wing having a rear surface having an angle with respect to the horizontal greater than the angle of repose. 10. The atomizer according to claim 9, in which the non-conductive material of the wing has a conductivity of about 10 ¹⁰ - 10 ¹⁶ Ohm / cm. 11. The atomizer according to claim 9, in which the angle of the aerodynamically smooth surface and the rear surface is less than 90 ^o , and the aerodynamically smooth surface is formed and positioned so as to direct the cloud from the element, and further includes an object that is approximately 2 distance from the wing, 5 - 15 cm, while the aerodynamically smooth surface directs the cloud to the object. 12. The atomizer according to claim 9, in which the angle of the aerodynamically smooth surface is less than 90 ^o . 13. The sprayer according to claim 9, in which the angle of the surface remote from the element is about 90 ^o .  14. The sprayer according to claim 9, in which the angle of the rear surface of the incidence is made with the possibility of any accumulation of powder on it from the wing towards the element for reuse. 15. The sprayer according to claim 9, in which the angle of the rear surface is enclosed in the range of about 45 - 70 ^o . 16. The sprayer according to claim 9, in which the angle of the aerodynamically smooth surface is in the range of about 45 - 70 ^o .  17. The atomizer according to claim 9, in which the wing has a surface in the form of a cylinder adjacent to the element, the surface being minimal.  18. The sprayer according to claim 9, in which the object is elongated, the element and the pallet are parallel to the elongated object, the wing has spiral edges in order to extend along the entire transverse width of the object.  19. The sprayer according to claim 9, in which the object is elongated, and the element, pallet and wing are located across the object.  20. The atomizer according to claim 1 or 2, in which the inlet is made diverging.  21. The atomizer according to claim 1 or 2, in which the outlet is made diverging.  22. The atomizer according to claim 1 or 2, in which the element is made to rotate at a speed of about 700 - 4000 rpm. / min  23. The atomizer according to claim 1 or 2, wherein the venturi cavity has a constant thickness between the inlet and the outlet of about 0.002-0.05 cm.  24. The atomizer according to claim 1 or 2, in which the element has a diameter greater than about 5 cm  25. The atomizer according to claim 1 or 2, in which the particle size of the powder varies in the range of 2 to 300 microns.  26. The sprayer according to claim 1 or 2, in which the element is a brush.  27. The atomizer according to claim 1 or 2, wherein the powder entering the venturi is larger than the powder exiting the venturi.  28. The atomizer according to claim 1 or 2, wherein the powder is selected from the group of powders consisting of thermosetting and thermoplastic organic polymers, organic materials, and combinations thereof.  29. The atomizer according to claim 1 or 2, wherein the cloud is a relatively uniform triboelectric cloud of powder particles suspended in a slowly moving stream of gas carrier. 30. The sprayer according to claim 1 or 2, in which the object is removed from the inlet by approximately an angle of 45 - 240 ^o .  31. A powder sprayer including a tray and a cylindrical element, the cylindrical element being mounted on the shaft for rotation around its axis, the pan is cylindrical and placed coaxially with the element, the pan partially surrounds the element, and the last and the pan are installed to form a cylindrical Venturi cavity into which the powder is supplied, the Venturi cavity having an inlet and an outlet that are spaced apart from each other, means for rotating the element inside the pallet with growths exceeding the speeds required for dropping the powder from the element by centrifugal force, while the element is configured to supply gas through the Venturi cavity and spray the powder entering the inlet to produce a uniform cloud of material particles, and is selected so as to maximize particle collisions with other particles with the element and thereby deagglomerate and reduce the particle size of the powder entering the venturi.  32. The atomizer according to claim 31, wherein the element is a brush having bristles, the bristles being selected with a transverse size and length and other physical properties together with the physical properties of the powder supplied to the Venturi cavity so as to grind agglomerates and reduce the particle size of the powder.  33. The sprayer according to claim 32, in which the bristles of the brush are flexible with the possibility of bending under the action of collisions between the bristles and particles with an increase in the degree of deagglomeration and a decrease in the particle size of the powder.  34. The sprayer according to claim 31, in which the bristles are cylindrical, having a length to diameter ratio of about 10: 1 to 5000: 1.  35. The sprayer according to claim 31, wherein the bristles have a parallelogram in cross section and the ratio of the transverse length to the longitudinal length is about 200: 1 to 800: 1.  36. The sprayer of claim 31, wherein the bristles have a parallelogram cross-section that is thicker in the direction of rotation of the bristles than in its transverse direction, the bristles having greater hardness and less flexibility in the direction of rotation than in the directions transverse to it .  37. The sprayer of claim 31, wherein the bristles are about 1.25 to 12.5 cm long.  38. The sprayer of claim 31, wherein the element and the pallet both have a length to diameter ratio of greater than 1.  39. The sprayer according to claim 31, wherein the wing is made that is located at a distance of about 0.002-0.05 cm from the element and includes an object that is about 2.5-15 cm away from the wing to which the cloud is directed.  40. The sprayer according to claim 39 or 9, wherein the object is elongated, and the element and the tray are angled to the object.  41. The atomizer according to claim 39 or 9, wherein the wing has a cylinder shape in cross section.  42. The sprayer of claim 39 or 9, wherein the wing has an aerodynamic surface, the surface being flat.  43. The sprayer according to claim 39 or 9, wherein the object is elongated, the element and the pallet are parallel to the object, and the wing has helical edges to extend along the entire transverse width of the object.  44. The sprayer according to claim 32, wherein the bristles are selected from the group of bristles consisting of natural fiber, synthetic polymer bristles, and metal bristles.  45. The sprayer according to claim 32, wherein the lateral size of the bristles is in the range of 2 times the material particle size to 50 times the material particle size.  46. The sprayer of claim 32, wherein the bristles have a transverse dimension in the range of about 0.002 to 0.155 cm.  47. The sprayer of claim 32, wherein the bristles have a length to transverse ratio of about 10: 1 to 5000: 1.  48. The sprayer according to claim 32, in which the bristles have a size in the direction of rotation in the range of about 0.002 to 0.155 cm  49. The sprayer according to claim 31, in which the bristles have a size in the direction transverse to the direction of rotation, in the range of about 0.002 to 0.155 cm  50. The sprayer of claim 31, wherein the bristles have a ratio of bristle length to lateral size in the range of about 200: 1 to 800: 1. Priority on points:
07/10/1996 PP 1-5, 9-50;
06/12/1997 on pp. 6-8.

Images