Abstract:
La presente invencion proporciona un aparato para controlar la pulverizacion de partículas de recubrimiento con carga positiva hacia un material dieléctrico puesta a tierra o con carga negativa que tiene una constante dieléctrica inferior a 4,0 y en forma de un recipiente hueco. Este aparato incluye: (a) un dispositivo (62) para inducir una carga positiva en una composicion de recubrimiento, (b) un dispositivo (62) para crear un campo de partículas de recubrimiento con carga positiva, (c) un dispositivo (64) para soportar una serie de recipientes huecos en relacion espaciada entre sí que incluye una serie de husillos verticalmente orientados, (d) un dispositivo para transportar los husillos en serie a través del campo de partículas de recubrimiento con carga positiva, (e) un plato de agarre (46) hecho de, o recubierto con, un material dieléctrico, o ambos, montado en el extremo superior de un husillo, teniendo el plato (46) un rebaje definido para recibir la boca de un recipiente hueco, y (f) un dispositivo de puesta a tierra (70) colocado de tal manera que, cuando el recipiente dieléctrico está en el corrido de las partículas de recubrimiento con carga positiva pulverizadas, el dispositivo de puesta a tierra también está en el recorrido pero protegido de ellas por el material dieléctrico. El dispositivo de puesta a tierra está aislado del contacto eléctrico directo con el recipiente soportado. El dispositivo de puesta a tierra se puede sustituir por unos medios de carga internos para inducir una carga negativa en un recipiente hueco que se soporta por dicho plato de agarre. Además, el dispositivo de puesta a tierra o el dispositivo de cara interno se puede usar en union con un dispositivo de carga externo para inducir una carga negativa en un recipiente hueco soportado por el plato de agarre.
Abstract:
Apparatus for electrostatically coating an elongated object of indefinite length which is aligned with the straight line path of the elongated object in a continuous manufacturing and finishing process. Electrostatic applicators are mounted to direct the coating into a substantially closed chamber at a portion of the elongated object passing therethrough. To substantially eliminate the explosive hazard occasioned by the use of an organic solvent-based coating material in the presence of electrical equipment, a combustibly inert atmosphere is maintained in the chamber and in an exhaust system leading therefrom. To maintain the electrostatic field, the coating chamber and associated coating equipment must be electrically isolated from ground.
Abstract:
Electrostatic spraying apparatus has two opposed electrodes (2) in housing (3) adjacent the path of spray from the spray nozzle (1), and a barrier (5) adjacent each electrode, the barrier including pointed protuberances (15) arranged so that liquid collecting on them is discharged electrostatically, each housing (3) being secured to the barrier (5) by a support (6t extending from a recess (7) within the housing.
Abstract:
In the electrostatic application of a coating material on to a product to be coated, the product leaves a supply hopper (1) over a tube enlargement (5A) and falls freely in a chamber (2) in the form of a tubular curtain. The tubular curtain falls around a central, elongate, vertical corona discharge electrode (6) so that a high voltage electrostatic charge of one sign is applied to the falling curtain of the product. Coating material is sprayed on to the product by atomizers (A1 to A6) in the chamber (2). A high voltage electrostatic charge of opposite sign is applied to the coating material by way of the atomizers (A1 to A6).
Abstract:
A paint spraying device for easily changing painting machines of different model types in accordance with spraying conditions, comprising a valve casing (1) having a color changing valve device (11), wherein the valve casing is adapted to act as a common member for allowing the selective mounting and/or dismounting of rotational spray head type electrostatic spraying machines (61, 71, 111), spray gun type electrostatic spraying machines (81, 101, 112) or the like, whereby it is possible to easily change and mount selected spraying machines (61, 71, 81, 101, 111, 112) in accordance with spraying conditions such as the configuration of a surface to be sprayed, type of paint and characteristics of a solvent. In addition, the color changing valve device (11) provided in the valve casing (1) can commonly be used for a plurality of types of spraying machines (61, 71, 81, 101, 111, 112).
Abstract:
The invention provides apparatus for electrostatically coating a pharmaceutical tablet core with powdered coating material. The apparatus comprises a first rotary drum (12) on which a core is held in electrical isolation from its surroundings but at a potential difference to earth by an electrode which contacts the core. The core is carried past a coating station B at which particles of powder having an opposite potential difference to earth are held in a tray (18). The surface of the drum is held at the same potential difference to earth as the powder particles. The powder is attracted to the core, and not to the drum, coating the exposed surface of the core. The drum carries the coated core past a fusing station C at which a heater fuses the powder to form a continuous film coating. The core is then turned and transferred onto a second drum (12') where the other surface is coated in the same way.
Abstract:
The invention is an applicator for electrostatically charging and dispensing particulate materials. The applicator has an arm (18) for conveying the material from a supply bin (14) to an electrostatic charging element (50) that is mounted within the arm for rotation. An electrostatic charge is applied to the charging element by a control system. Particulate material is contacted by the rotating charging element, electrostatically charged, and dispensed by the charging element through an opening (54) in the arm.
Abstract:
The invention relates to a electrostatic spray apparatus, including a hood (11). The hood (11) defines a top region (11a) with a depending skirt (11b-e) and comprises first and second hood elements, either or both of which may comprise moulded shells, with an electrode sandwiched therebetween. The electrode extends over said top region (11a) and down the skirt (11b-e) to terminate short of the lower regions of the skirt (11b-e). The hood (11) is so constructed that, other than at the lowermost regions of the skirt (11b-e), said hood (11) does not have any junction of its planer surfaces having a radius less than one hundred and fifty millimetres. The hood has an opening (17) in its top region through which an electrostatic spray head (18, 19) is entered into the hood (11), the electrode presents a connection (28) for an electrical supply and the potential applied to the spray head (18, 19) is substantially the same as that applied to the electrode.