Abstract: Apparatus for powder coating various types of parts using different powder coating techniques. The apparatus includes a powder coating hood in which the coating operation takes place and a powder collection booth connected to the hood for drawing air and excess powder out of the hood. An air circulation system is provided in the collection booth for drawing excess air and powder from the hood. An air flow regulator is provided to adjust the draw of air and powder between low and high amounts. A low amount is, for example, useful for electrostatic fluidized bed coating, while a higher amount may be useful for spray coating techniques.

Abstract: An apparatus and a method for coating zinc on steel sheets for use on automobiles and electronic apparatuses are disclosed. A fluidized bed forming chamber is provided to fluidize zinc powders in carrying out a zinc coating on a heated steel sheet, so that not only a uniformly coated layer but also a thick coated layer can be obtained. The apparatus for continuously coating zinc on a steel sheet according to the present invention includes a zinc coating chamber for forming a fluidized bed of zinc powders, for passing a heated steel sheet through the fluidized bed of the zinc powders, and for making the zinc powders melt-adhere on the steel sheet during its passing through the fluidized bed. A fluidized bed forming chamber forms a fluidized bed of the zinc powders by making the zinc powders suspended by spouting a gas.

Abstract: A method for producing continuous and discontinuous fiber metal matrix composites (CFMMC). The method uses aerosolization of finely divided metal powders in a controlled atmosphere which prevents explosions to coat the fibers and then the metal coated fibers are consolidated to form the CFMMC. The composites are useful as heat sinks for electrical components and in applications where a structural reinforced metal matrix composite is needed.

Abstract: Apparatus for use in applying particles to an external layer of uncured resin material of a coating of an optical fibre unit with at least one optical fibre, said apparatus including means (50) defining an axially extending through-passage (52) through which, in use, such an optical fibre unit is passed, said passage defining means having an inlet (62) for admitting fluidized particles into said through-passage, and said through-passage being provided with means (64) for generating turbulence in such fluidized particles in said through-passage.

Abstract: The present invention provides a method and composition for on-line treatment of furnace walls that are subject to deposition of highly reflective ash. The method involves exposing the walls to a darkening agent, or a combination of a darkening agent and a fluxing agent. The darkening agent, or the combined darkening agent and fluxing agent, may be mixed with the coal before it enters the boiler. Preferably, the appropriate walls of the boiler are treated directly with the darkening agent. A preferred embodiment involves direct application of the darkening agent to the water wall.

Abstract: A method and a device for controlling the outflow of fluid powder from a container can be used for controlling the expulsion of powder out of a powder-spraying apparatus for electrostatic coating. The disadvantages of a mechanical closing device are avoided by introducing closing air into an extraction pipe for extracting fluidized powder out of a container. The closing air is introduced through a pipe which opens into an orifice in the casing of the extraction pipe. The mass flow of fluidized powder can be controlled by an appropriate setting of a pressure in the extraction pipe in relation to the pressure in the fluid bed, that is to say by the introduction of closing air at an appropriate pressure.

Abstract: The electrostatic fluidized bed coating apparatus and system employ a vertically extending gaseous vortex of charged particles. Effects of variations in particle distribution, size, and electrostatic charge strength are minimized by the vertical orientation, enabling the production of coatings of exceptional uniformity. The apparatus is especially suited for construction to simultaneously coat a number of strands of wire or the like.

Abstract: The apparatus has a container which contains a first filter. During operation, this separates the first interior region containing particulate material from a second interior region. The latter is connected to a downstream dust separator. This has a housing which contains a second filter. The apparatus furthermore has a fan, at least one dust concentration sensor and a control device connected to this and to the fan. During fluidization and treatment of the particulate material in the first interior region of the container, the dust concentration in the oxygen-containing gas flowing from the first filter to the second filter and usually consisting of air is measured. If the dust concentration is at least equal to a predetermined limit below the lower explosion limit, the control device switches off the fan. This makes it possible to keep the pressures generated by any dust explosion relatively small.

Abstract: A powder coating system for difficult to handle powders includes a powder hopper containing fluidized powder particles, a pump body connected to the hopper and having an inlet in communication with the hopper, an ejector nozzle mounted to the pump body and aimed at an outlet thereof, a second nozzle mounted to the pump body and aimed at the inlet thereof and a powder application device for receiving powder particles from the outlet of the pump body and spraying them onto an article to be coated. The ejector nozzle sprays pressurized air toward the outlet to transport powder particles along a flow path which extends from the powder hopper into the pump body via the inlet and then out of the pump body via the outlet. The second nozzle sprays air pulses at the inlet in a direction opposite the particle flow along the flow path caused by the ejector nozzle. This spray from the second nozzle creates microvibrations in the inlet of the pump body to eliminate powder particle adherence and cohesion thereat.

Abstract: A fiber bundle workpiece is coated with a particulate material during passage about a plurality of pulleys arranged to establish a serpentine travel path portion through a coating zone. The pulleys have arcuate grooves extending thereabout, which cause the fiber bundle to twist axially, and the fibers of the bundle move with respect to one another as the fiber bundle moves along the serpentine path. These two actions increase coating efficiency and the penetration of particulate material into the fiber bundle. The travel path portion will preferably lie in a horizontal plane, and the coating unit will normally constitute an electrostatic fluidized bed of particulate material. After exiting the coating zone, the fiber bundle may pass through an oven to partially melt the particulate material, and thereby cause the particles to adhesively attach to the fiber bundle.

Abstract: A method for surface treatment in which a fluidizable powder mixture consisting of a powder of a refractory material, and a surface layer-forming powder of a metal, or alloy or both is fluidized by a fluidizing gas supplied through a gas distributor to form above the gas distributor a fluidized bed in which a surface layer is formed on the material to be treated under heating in the presence of a halide. A layer of coarse particles is disposed between the fluidized bed and the gas distributor, and the coarse particles have a mean diameter, D(m), as defined below:(1650V.mu./PG).sup.1/2 <D<6.5dwhereV: velocity of the fluidizing gas (m/s);.mu.: viscosity coefficient of the fluidizing gas (kg/m.multidot.s);P: mean density of the coarse particles (kg/m.sup.3);G: acceleration of gravity (9.8 m/s.sup.2);d: mean particle diameter of the surface layer-forming powder (m).

Abstract: A method for coating particulate substrate materials is provided which comprises (a) combining particles and an electrolyte in an imperforate container; (b) vibrating the container to generate a fluidized bed of particles in the electrolyte; and (c) electrochemically depositing a coating on the particles from reactants in the electrolyte. An apparatus for coating particles is also provided which comprises an imperforate container for receiving particles to be coated and an electrolyte and a device for generating a fluidized bed in the container, the device being operatively associated with the container.

Abstract: This is a granulating-coating apparatus comprising: a spraying means for spraying a binder liquid or a coating liquid onto articles to be processed, which are received in a rotary drum; a brush provided in a manner to be movable relatively to the spraying means in the rotary drum, for contacting a spray gun formed in the spraying means and removing adhered articles on the spray gun; and an adhered article sucking device provided in the vicinity of the brush, for receiving the removed adhered articles. With this arrangement, the adhered articles on spraying openings of the spraying means can be removed completely without contamination of the articles to be processed with the removed adhered articles.

Abstract: A free-flowing powder of coated particles is produced by means of a spray dying plant using a hot drying gas or a spray cooling plant using cold drying gas. A coating composition in liquid form is supplied to the atomizing means of the plant, and the liquid coating composition is atomized into a flow of liquid droplets, which are allowed to collide with particles of a carrier material dispersed in a transport gas. The direction and rate of flow of the transport gas are adapted to prevent contact between the drying gas and the droplets, so that the liquid coating composition, before any substantial drying thereof, will form a continuous liquid coating layer on the particles. The thus applied continuous coating layer on the particles is then allowed to at least partially dry by contact with the drying gas before withdrawal of the coated particles from the spray-drying chamber of the plant to a moving bed in the form of loose agglomerates.

Abstract: Process for the continuous fluidized bed agglomeration wherein the granulating liquid together with propellant air is supplied centrally through a three-phase nozzle on the distributor of the fluidized bed, and at the same time, the solid in powder form is fed into the fluidized bed through the annular space or the three-phase nozzle with the air of a current of propellant air, supplied separately and concentrically.

Abstract: A process for continuously producing coated particles, and in particular, particles in which the coating is uniform, contiguous and of minimal thickness is described, together with an apparatus for conducting the coating process in which a plurality of coating cells connected in series are provided wherein the particles are pneumatically conveyed during the coating application and in which controlled recirculation of particles occurs within each cell and a controlled spray is applied to the particles in order to produce a substantially uniform distribution of coating.

Abstract: An apparatus and method for continuously producing polymer coated particles, and in particular, a polymer coated fertilizer, wherein the coating material used is, for example, an aqueous film forming latex. The coating process is conducted with a plurality of fluidized beds, connected in series, under conditions such that, preferably, the relative humidity of the air in the initial coating zones is maintained below the critical relative humidity of the particle to be coated. The apparatus and process provides a method to prepare coated particles having a narrow coating weight distribution, and thus allows for the economical production of a slow release fertilizer.

Abstract: An apparatus and method for continuously producing polymer coated particles, and in particular, a polymer coated fertilizer, wherein the coating material used is, for example, an aqueous film forming latex. The coating process is conducted with a plurality of fluidized beds, connected in series, under conditions such that, preferably, the relative humidity of the air in the initial coating zones is maintained below the critical relative humidity of the particle to be coated. The apparatus and process provides a method to prepare coated particles having a narrow coating weight distribution, and thus allows for the economical production of a slow release fertilizer.

Abstract: Apparatus for producing refractory material filaments comprises an enclosure (11), means for heating the constituents of the refractory material, non-contacting means to support a drop (17) of molten material such as silicon, being one of the constituents of the refractory material within the enclosure and means to transport a filament (10) such as carbon, being a second constituent of the refractory material, through the drop of molten material in use. A levitation coil and/or an inert gas jet is used to support the drop of molten material and a silica glass or other refractory tube (13) is used to direct the gas jet. The enclosure has opposed side arms (15, 16) respectively for entry and exit of the filament (10) or the filament may be passed vertically through the molten silicon drop. An inclined side tube may be provided through which grains of silicon may be introduced into the enclosure for addition to the molten drop.

Abstract: An improved reactor for a high-temperature deposition reaction on seed particles is constructed with a fluidized bed which is divided into a heating zone and a reaction zone by a partition. Seed particles in the heating zone are fluidized by a carrier gas and are heated by microwaves. On the other hand, the reaction zone for the deposition reaction, through which reaction gases pass, is heated by particle mixing between the reaction zone and the upper section of the heating zone. Subsequently, a desired reaction temperature at the reaction zone is maintained stable without deteriorating the microwave heating of the heating zone.

Abstract: The centrifugal fluidizing granulator for powder coating granulation has a sensor for detecting changes of viscosity of the growing particles by means of a load cell or a displacement detector; and output signal of the sensor is compared with the data stored in a memory contained in a control unit which determines whether the growing particles are in their wetted state or dried state. The control unit controls the spraying of the liquid and the dispersion of the guest powder based on the result of the comparison.

Abstract: Precise control of pyrocarbon being coated upon an object in a fluidized particle bed is achieved by monitoring the weight change of the fluidized particle bed over a period of time. Measurement of such weight change is truly representative of bed size in such a coater, which is a most important factor in achieving the desired characteristics of the pyrocarbon being deposited. By monitoring the bed size by repeatedly determining such changes in the weight, compensating adjustments are made by either adding additional particles to the bed or by changing the rate at which particles are withdrawn so that precise coating characteristics are achieved, and coatings can be deposited within very close thickness tolerances.

Abstract: A coating-fluidizing gas supply system for a flat-bottom fluidized bed coater that maintains a high degree of uniform fluidization of levitated particles for a long enough time period to coat medical-device components. The coating-fluidizing gas supply system prevents premature pyrolysis of the coating component of the gas from plugging gas-distributor holes of a flat plate at the bottom of a flat-bottom fluidized bed coater, by directing multiple gas streams uniformly against the entire undersurface of the flat gas-distributor plate, creating an overall cooling-effect on the gas-distributor plate which prevents clogging.

Abstract: Apparatus and continuous process for impregnating fibers with polymer powders in which the fibers are caused to circulate in an aerosol passed through a fluidized bed contained in an earthed fluidization vessel. The particles constituting the fluidized bed are chosen so as to charge the powder particles electrostatically. The aerosol is continuously fed with a flow of fresh powder particles equal to that at which it is desired to impregnate the fibers per unit time and all the powder particles previously introduced which have not been impregnated into the fibers are continuously reintroduced into the fluidized bed without any change in the supply flow rate of fresh powder particles.

Abstract: Transport apparatus for small sized hardware items includes a fluidized bed with a sloping gas permeable base (6) at the inlet end of the bed. Gas feed chambers (6a, 6b, 6c, 6d) are located on the lowerside of the base (6) and are sealed from one another in a gas tight manner. Powder columns (2a, 2b, 2c, 2d) of different heights extend upwardly above the base (6). Gas at different pressures is supplied through the gas feed chambers (6a, 6b, 6c, 6d) into the powder columns forming a uniform fluidized bed (2). The base slopes downwardly and has step-like transitions adjacent intersections of the chambers.

Abstract: A fluidized coating apparatus wherein a rotatable perforated disk 2 is provided at the lower portion of a processing cylinder 1 and perforated disk opening portions 3 are provided in the vicinity of the outer peripheral edge of this perforated disk 2. The ratio of the total opening area of the perforated disk opening portions 3 to an area of an annular slit 8 formed between the perforated disk 2 and the inner wall of the processing cylinder 1 is within the range from 0.2 to 0.6. Each of the perforated disk opening portions 3 is provided with a cover and side walls so that gas is blown out outwardly in the radial direction or obliquely backward with respect to a rotating direction within 30.degree. to the radial direction of the perforated disk.

Abstract: A fluid-bed particle coater having a dual-jet and spray arrangement and including an upstanding column which has an upper cylindrical section, a tapered intermediate section and lower cylindrical section. Depending from the lower cylindrical section is a cylindrical chamber which is inner-connected to tubular sections adapted for introducing multiple air streams via separately controlled inlet openings. The dual-jet and spray construction includes an upwardly-facing spray nozzle positioned in coaxial relationship to the tubular sections and a draft tube, and a downwardly-facing spray nozzle contained with a fountain tube which is disposed above the draft tube. The fountain and draft tubes concentrically intersect about the intermediate section of the column in an opened telescopic arrangement.

Abstract: An apparatus and method for coating surfaces of workpieces employs an electrostatic fluidized bed unit for producing a cloud of charged particles, for deposition upon the workpiece, and a second fluidized bed for agitating the particulate material and for facilitating feeding thereof to the electrostatic coating bed, the second bed being disposed beneath the first bed, and being in powder flow communication with it.

Abstract: A shield, such as an upstanding cylindrical partition, is mounted adjacent to an air source, such as an air distribution plate/screen of a Wurster system processor, whereby the open upper end of the partition is generally horizontally registered with and disposed about the upper extremity of an associated spray nozzle. The open lower end of the inner cylindrical partition is generally sealed relative to the air distribution plate/screen and operative to receive air upwardly therethrough for subsequent passing through the inner partition about the spray nozzle. The upper end of the inner tubular partition shields the initial spray pattern discharged from the spray nozzle and prevents the premature entrance of particles moving into the spray nozzle area.

Abstract: Electrostatic fluidized bed coating apparatus consists of an horizontal porous plate and a contiguous, vertical porous plate. Charged particles exiting the bed formed on the horizontal plate fall past the outer surface of the vertical plate, and are electrostatically recharged by ionized air issuing through it, thereby effectively extending the operative vertical length of the bed and substantially increasing coating efficiency.

Abstract: An apparatus and method for continuously producing polymer coated particles, and in particular, a polymer coated fertilizer, wherein the coating material used is, for example, an aqueous film forming latex. The coating process is conducted with a plurality of fluidized beds, connected in series, under conditions such that, preferably, the relative humidity of the air in the initial coating zones is maintained below the critical relative humidity of the particle to be coated.

Abstract: The present invention is directed to an apparatus useful for fluidizing small particulate solids having a diameter of less than about 50 microns in average particle size, and at least partially enveloping these small solids with a coating material or a precursor thereto. The basis apparatus of this invention includes a cross-current multi-stage fluid bed reactor having N fluid beds in flow communication with one another, wherein N.gtoreq.2.

Abstract: In a method of operating a fluidized bed, gas under pressure is distributed into the bed through a gas permeable member extending transverse to the bed and a gas permeable wall of a discharge conduit wherein the relative permeability of the gas permeable member and the conduit is selected so as to obtain a desired distribution of gas entering the bed and a desired effect on the fluidization pattern in the bed.

Abstract: A process is described for coating a substrate surface in a heated fluidized bed reactor which comprises flowing one or more coating source materials in a condensed state into a fluidized bed reactor which is maintained at a temperature which is higher than the decomposition and/or reaction temperature of the one or more coating source materials but lower than the vaporization temperature of the coating composition formed in the reactor, whereby the coating composition formed by such decomposition and/or reaction will form a coating film on the substrate surface.

Abstract: A powder spray coating system has a controller configurable to a variety of different system configurations. Configuration data is keyed by an operator from menu prompts and stored for use by a microprocessor based operating program to operate the supply of powder and air to a powder spray gun. The microprocessor also presents information from monitored parameters of the system, including the supply air dew point which is monitored to provide warning signals of potential condensation in the system. Dew point detection is accomplished by measuring temperature and relative humidity and comparing the measurements with values for air at the maximum acceptable dew point. Alternatively, measurement of absolute humidity and supply air pressure are used to compute the dew point of the air which is compared with the actual temperature and maximum dew point temperature.

Abstract: Apparatus and methods are provided for coating relatively small quantities of particles including tablets, pellets, or granules. The device effectively fluidizes the particles to be coated by controlled vibration of a perforated platform through which drying air is passed during intermittent spraying of the particles with a solution of organic or aqueous-based coating material. The method coats individual tablets having as low a mass as 50 mg and coats quantities ranging from less than about 50 mg to 10 g of tablets, pellets, or granules.

Abstract: A fluidization and conveyor arrangement for electrostatic powder coating devices. The arrangement includes a container pivotable by 180.degree. on a carrying frame, and a cover, having a fluidization plate. A powder discharge tube and a compressed air tube pass through the cover and into the container. A transport package, for example a sack filled with powder, is introduced into the container. The container is then closed with the cover, and is pivoted by 180.degree. to an operating position, in which fluidization and discharge of the powder may be affected.

Abstract: An apparatus for producing an electrostatic image developer carrier from a material, comprising; a chamber for providing an enclosed space in which the material is processed, a stirrer for stirring the material in a horizontal direction in the chamber, and at least one of: a heater for heating up the chamber to a predetermined temperature, and a cooler for cooling down the chamber to a predetermined temperature.

Abstract: A system and method for uniformly coating one or more fibers (10) with particles of a material is described. The method uses a vibrator preferably an acoustic speaker (17b) in a housing (17c) to fluidize the particles (P.sub.1) in a chamber (17 or 30) to deposit them on spread fibers (10b). The fibers can be in the form of a tow of fibers. After the particles are coated on the fibers, the particles can be bonded to the fiber such as by using a heater (19). The resulting product has a uniform deposit of the particles and in the case of the tow of fibers can serve as a prepreg for laminate structures to be produced from the coated tow of fibers.

Abstract: A fluidizing and suction withdrawal unit (14) which can be lowered into a container (20) holding a powder (22), in order to fluidize the powder and withdraw the fluidized powder (92) by suction. The fluidizing and suction withdrawal unit (14) is provided with a level sensor (88) which generates a signal, in contingence on the immersion depth (80, 82) to which the fluidizing and suction withdrawal unit (14) is immersed in a powder layer (92) fluidized by it. This assures a consistent feed capacity which also in the case of direct connection of a spray device (76) results in the coating of articles at good coating qualities.

Abstract: In a container (12) a treatment space (14) for substance (16) is arranged and therebelow a wind chamber (22). The wind chamber (22) is defined upwardly by a circular rotor disc (42) which is rotatable drivably about an upright central (42) which is rotatable drivably about an upright central axis (A) and has at least one opening (44) which is elongated in approximately radial direction and which allows a gas stream (50) from the wind chamber (22) into the treatment space (14). The rotor disc (42) forms the sole partition between wind chamber (22) and treatment space (14). Associated with the or each opening (44) of the rotor disc (42) is a closure means which is opened in normal operation but is closable for stopping the apparatus. Stationarily arranged above the rotor disc (42) is at least one retaining blade (98) which prevents substance lying on the rotor (40) from rotating with the latter.

Abstract: The present invention relates to a fluidized bed apparatus comprising a fluidization grid arranged in the lower part of this apparatus, this grid being provided at its center with a circular aperture communicating with a discharge chamber and occurring in the form of a surface of revolution consisting of the joined lateral surfaces of at least two coaxial truncated cones of revolution, virtual vertices of which are oriented downwards.

Abstract: A granulating and coating method using the drying air streams to effectuate granulating, coating and drying and apparatus therefore wherein:a nozzle for supplying an article to be coated and another nozzle for supplying a coating material are provided at such positions that the article to be coated and the coating material collide with each other before the article to be coated and the coating material are dispersed by the drying air streams.

Abstract: This invention is a process for the uniform application of polymer powder particles to a filamentary material in a continuous manner to form a uniform composite prepreg material. A tow of the filamentary material is fed under carefully controlled tension into a spreading unit, where it is spread pneumatically into an even band. The spread filamentary tow is then coated with polymer particles from a fluidized bed, after which the coated filamentary tow is fused before take-up on a package for subsequent utilization. This process produces a composite prepreg uniformly without imposing severe stress on the filamentary material, and without requiring long, high temperature residence times for the polymer.

Abstract: A coating system is provided with a controller which transforms a demand signal responsive to the speed, relative to the dispensing apparatus, of an object to be coated, into a control signal which adjusts for the non-linear output characteristics of the flow of coating powder through the dispensing apparatus to cause the material to be dispensed with a uniformity that is corrected for the non-linear relationship between those output characteristics and the speed of the object. In the preferred embodiment, the system corrects for the non-linear characteristics of different powder pumps in dispensing different powder coating materials upon objects carried by variable speed conveyors. A plurality of stair-step tables are stored in the memory of the controller. Each table represents a different selectable powder pump to provide a desired powder pump output characteristic.

Abstract: The apparatus and system utilize sprays of steam to clean the exterior or laminated objects, preliminary to electrostatic powder coating, as well as to effect volatilization of liquid contaminates trapped between lamina thereof. Off-gassing that would otherwise occur when the objects are heated to effect fusion of the powder deposit is thereby avoided. The apparatus includes a conveyor for transporting a workpiece along a horizontal travel path through a chamber, above and below which path a spray compartment and collecting compartment are defined, respectively.

Abstract: Apparatus and method for coating interior surfaces of objects employs an electrostatic fluidized bed unit in which the fluidization chamber is relatively shallow, and is circumscribed by a marginal portion that conforms closely to the dimensions and configuration of the cavity of the object. The apparatus employs, as a feature of its recovery and recirculation system, a fluidized bed for agitating and facilitating feeding of the particulate material, thus making the system especially well suited for depositing coatings of abrasive materials, such as vitreous frit.

Abstract: Method and apparatus for coating mouldings consisting of fluidizing the mouldings by means of a rotating spiral gas flow. A holder (A) containing the mouldings is provided with gas inlets (3). A gas flow through the gas inlet (3) brings the mouldings in a spiral rotating movement in a sphere (C) placed on holder (A). Coating material is sprayed in the apparatus by a tube (D), oscillated by the gas flow, on the whirling mouldings.

Abstract: Electrostatic apparatus and method for coating interior surfaces of objects. The apparatus employs a fluidized bed unit in which the fluidization chamber is relatively shallow, and is circumscribed by a marginal portion that conforms closely to the dimensions and configurations of the cavity of the object. The apparatus employs a non-vacuumized powder recovery and recirculation system, and provides a peripheral slot in the marginal portion of the housing for entry of undeposited powder. Coating inside corners of objects is effectively achieved using the method of the invention, and heavy, uniform builds of the particulate material are produced efficiently and at high rates.

Abstract: A new process for continuously preparing granules having narrow grain size distribution, comprisinga. spraying the product to be granulated in liquid form into a fluidized bed,b. separating the proportions of fine material escaping from the fluidized bed from the off-gas and returning said fine material to the fluidized bed as nuclei for granule formation,c. setting the fluidizing gas flow such that granules are formed which are of a predetermined size, andd. removing the completed granules solely by way of at least one countercurrent gravity classifier inserted into the outflow bottom of the fluidized-bed vessel.A new apparatus for carrying out the process according to the invention and new granules.