Abstract:
A power supply for an electrostatic powder spray gun is formed in the shape of a hollow cylinder with a central passageway therethrough. A powder tube is slideably inserted through the central passageway of the power supply thus providing a more compact and symmetric spray gun profile. The power supply may be a voltage multiplier, for example.
Abstract:
A high-speed rotary atomizer for applying powder coating comprises in a known manner a housing (1), in which a motor (13) is accommodated. The motor (13) rotates a bell-shaped plate (16) which is disposed at the front of the housing (1). At least one powder supply duct (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) leads through the housing and opens at the front of the housing (1). Its cross section can therefore be kept very large, thereby increasing the powder output of the high-speed rotary atomizer. This also enables a plurality of powder supply ducts (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) to be laid, which in turn results in a higher powder throughput and improved homogeneity of the powder cloud which is produced.
Abstract:
A device and method for atomizing a liquid medium, including an electrically conductive nozzle body with an internal volume for holding the liquid medium, at least one nozzle opening as well as a high-voltage electrode arranged inside the internal volume coaxially to a longitudinal axis of the nozzle body. The high-voltage electrode is provided in the area of its greatest lateral expansion with a circumferential, sharp edge that extends at a small distance to the nozzle body in order to be able to bring about the electrostatic charging of the passing liquid medium. This construction enables the electrostatic atomization in a simple manner even for multi-hole nozzles, so that the electrostatic atomization also can be used in the field of gas turbine technology for improving the injection in the start-up and partial load range.
Abstract:
An electrostatic spray device that maintains a consistent charge-to-mass ratio in order to maintain a consistent target spray quality is disclosed. During steady state conditions, the high voltage power supply adjusts the output voltage level in response to changing environmental and/or operating conditions. During transient conditions such as start-up, shut-down and changing flow rate conditions, the high voltage power supply ensures that the charge-to-mass ratio is maintained. During, start-up, for example, the high voltage power supply charges the high voltage electrode to a predetermined voltage level before the product is delivered to the charging location. During shut-down, the product delivery is stopped before the high voltage power supply shuts off power to the high voltage electrode, and during changes in product flow rate, the voltage level of the high voltage electrode is adjusted to maintain a consistent charge-to-mass ratio. The present invention also prevents afterspray by discharging the stored charge remaining in storage elements of the high voltage power supply.
Abstract:
A plurality of unconventional negative tribo-charging materials are described for use as the powder contact surfaces in tribocharging and corona powder spray guns, gun components, and powder delivery system components. The invention also provides a short s barrel tribo-charging powder spray gun (200) having an interchangeable powder contact insert (220) and nozzle (230), with turbulence inducing air jets. The invention further provides novel tribocharging and corona gun designs. Improved powder coating systems are made possible wherein, for example, negative tribo guns can be utilized with negative corona guns to coat different parts of the same workpiece in a powder coating system Also provided is an inside-out configuration in which pressurized air directs powder coating material outward towards a charging surface. Additional configurations provide air jet (981) induced tribocharging and conventional tribocharging portions combined in a single gun. Also provided is a spraying apparatus that combines tribocharging and/or directed air tribocharging with corona charging. A switch arrangement (1000) is provided to select or change charging modes of the spraying apparatus.
Abstract:
Apparatus for the electrostatic powder paint spray coating of substrates, such as automotive vehicles, is provided. The apparatus includes modular applicators which are mountable into a programmable, robotically controlled housing. The modular applicators are switchable into and out of an operational mode on command, to facilitate different optimal coating procedures for coating differing surfaces, ranging from large, open surfaces to smaller, highly irregular substrate surfaces. The applicator heads may be spatially switchable on command from, for example, a bell cup spray applicator to a spray gun applicator. Flow control to each applicator is preferably enhanced using selectable pneumatically controlled pinch valves.
Abstract:
Water-based invisible red fluorescent inks provide machine-readable, inverse-contrast invisible images and can be printed using conventional ink jet printers. The inks employ rare earth complexed ligand fluorophores having narrow excitation and emission spectra. In one embodiment the images are printed with an ink comprising water and a water-soluble organic fluorescent fluorophore, which when printed and dried on paper is invisible to the eye and fluoresces in the green to infrared range, e.g., from about 550 to 1200 nm, when irradiated with short wave length UV radiation, e.g., from 230 nm to 280 nm. The highly specific excitation and emission rates, coupled with a high inverse contrast on papers of all colors, makes them particularly useful as ink jet inks for postal and other purposes.
Abstract:
Provided is a system for delivering a liquid sample to an inlet of an analytical instrument. Included is an acoustic ejector driven by a drive system that generates drive signals provided to the ejector. The drive signals are generated with a pulse width sufficient to eject at least a portion of the liquid sample. A reservoir provided for holding the liquid sample is in operational arrangement with the acoustic ejector. A liquid sample voltage source is located within the reservoir, and the liquid sample voltage source is designed to provide a charge to the liquid sample. An analytical instrument voltage source is in operational arrangement with the analytical instrument and is designed to provide a voltage bias between the reservoir and the analytical instrument. In another aspect of the invention, provided is a method for delivering a liquid sample to an inlet of an analytical instrument. The method includes generating an acoustic drive signal, with a pulse width sufficient to eject at least a portion of the liquid sample below a short pulse limit. The drive signal is delivered to an acoustic ejector whereby the acoustic ejector generates an acoustic wave. The acoustic wave is directed into a reservoir holding the liquid sample, wherein the acoustic wave is focused substantially at a surface of the liquid sample. This design results in the emitting of at least a portion of the liquid sample.
Abstract:
A dispensing device for dispensing a material. The dispensing device includes a somewhat cup-shaped interior opening in a first direction in which the material is to be dispensed from the dispensing device. The interior terminates at a discharge edge. The dispensing device further includes a skirt extending from the discharge edge in a second direction generally opposite the first direction. The skirt includes multiple passageways substantially equally spaced around a perimeter of the skirt.
Abstract:
A powder spraying gun generates a desired pattern of electrostatically charged particles for coating a workpiece without rotating parts or particle deflectors. The powder pattern is generated with a funnel-shaped output in conjunction with air introduced into a powder charging chamber of the gun in a tangential swirling motion. The swirling air is additionally used to purge agglomerated powder particles from the charging electrodes in the charging chamber. The charging chamber surface is fashioned from material exhibiting low friction or high resistance to powder impact fusion.