Abstract:
The present invention harvests and utilizes fluidized bed drying technology and waste heat streams augmented by other available heat sources to dry feedstock or fuel. This method is useful in many industries, including coal-fired power plants. Coal is dried using the present invention before it goes to coal pulverizers and on to the furnace/boiler arrangement. Coal can be intercepted on current coal feed systems ahead of the pulverizers. Drying fuel, such as coal, is done to improve boiler efficiency and reduce emissions. A two-stage bed utilized in the process first “pre-dries and separates” the feed stream into desirable and undesirable feedstock. Then, it incrementally dries and segregates fluidizable and non-fluidizable material from the product stream. This is all completed in a low-temperature, open-air system. Elevation of fan room air temperature is also accomplished using waste heat, thereby making available to the plant system higher temperature media to enhance the feedstock drying process.
Abstract:
A voltage block device for use with electrostatic spraying apparatus for conductive coatings is disclosed. The device maintains an air gap which electrically isolates a grounded paint supply from a charged spray head to prevent the leakage of potential to the grounded paint supply. The device comprises a tube made of non-conductive material and having ends which are closed by upper and lower caps to define a closed space which is pressurized. A valve secured in the upper cap delivers paint into the closed space to raise the level of conductive coating material therein to the level of an external sensor. In a first mode of operation, valve interlock circuitry opens the valve when the spray head is not charged and the sensor detects a low level of coating material. The valve closes if the level of conductive coating material in the closed space reaches the external sensor or the spray head becomes charged, restoring an air gap which electrically isolates the grounded paint supply. In a second mode of operation, the valve interlock circuitry includes a timer and opens and closes the valve intermittently, when needed, so it dispenses discreet bodies of conductive coating material separated from each other, the upper cap and the conductive coating material in the cylinder by one or more air gaps having a combined length sufficient to electrically isolate the grounded paint supply. This valve cycle is repeatable and permits continuous charged operation of the spray head.
Abstract:
An improved control circuit for protecting a high voltage DC electrostatic system from arcing by removing the high voltage from the electrostatic system under incipient arcing conditions. A signal having a voltage proportional to the instantaneous high voltage current in the electrostatic system is established. DC components and unwanted noise and unwanted AC components are removed from the signal to leave only signal components relating to the rate of change of the current in the high voltage system and information indicative of incipient arcing conditions. When the remaining signal exceeds a predetermined reference level, high voltage is removed from the electrostatic system.
Abstract:
A rotary atomizer includes a manifold assembly adapted to be attached to a mechanism for moving the atomizer and an air bearing turbine motor housing assembly releasably secured to the manifold assembly. Sources of pressured fluid for actuating the atomizer and coating fluid are connected to the manifold which has fittings for releasably sealing to apertures in the rear cover of the housing assembly. The opposite end of the housing includes a shaping air cap and a shaping air ring which cooperate to define an annulus for discharging a thin ring of shaping air over the peripheral edge of an atomizer bell to direct fluid particles toward a target. Exhaust air from the turbine motor is vented to the inside of the housing and directed to a chamber behind the atomizer bell to aid in directing the fluid particles. A magnetic speed pickup generates a signal which is coupled through a circuit that electrically isolates the high voltage which is applied to the atomizer to electrically charge the coating particles.
Abstract:
The present invention relates to a mounting structure for securely and accurately positioning an object on a rotatable shaft. In the preferred embodiment, the mounting structure is utilized to position a rotary bell on a rotatable shaft of a rotary atomizer coater. More specifically, the mounting structure includes a rotatable shaft member having an axis and adapted to be connected to a rotating drive mechanism. The shaft member is provided with a first tapered mounting position. An object is adapted to be securely mounted on the shaft member for rotation therewith, and is provided with an internal bore having a second tapered mounting portion engageable with the first tapered mounting portion. The first and second tapered mounting portions cooperate to accurately align the object with respect to the shaft member. In accordance with the present invention, one of the first and second tapered mounting portions includes a plurality of axially spaced apart and generally annular grooves defining tapered land surface portions therebetween. The other one of the first and second tapered mounting portions defines a tapered surface engageable with the tapered land surface portions for securely and accurately positioning the object on the shaft member. In the preferred embodiment of the invention, the grooves are uniformly spaced apart and have a predetermined width which is substantially equal to the width of each of the tapered land surface portions. Also, one of the first and second tapered mounting portions which includes the grooves is formed of a material such as aluminum, while the other one of the first and second tapered mounting portions is formed of a harder material such as steel.
Abstract:
A rotary atomizer including a manifold assembly adapted to be attached to a mechanism for supporting and/or moving the atomizer and an air bearing turbine motor housing assembly releasably secured to the manifold assembly. Sources of pressured fluid for actuating the atomizer and coating fluid are connected to the manifold which has fittings for releasably sealing to apertures in the rear cover of the housing assembly. The opposite end of the housing includes a shaping air cap and a shaping air ring which cooperate to define an annulus for discharging a thin ring of shaping air over the peripheral edge of an atomizer bell to direct fluid particles toward a target. Exhaust air from the turbine motor is vented to the inside of the housing and directed to a chamber behind the atomizer bell to aid in directing the fluid particles. A magnetic speed pickup generates a signal which is coupled through a circuit that electrically isolates high voltage which is applied to the atomizer to electrostatically charge the coating particles.
Abstract:
A high speed non-incendive rotary painting assembly including a high voltage power supply, an air supply means and a paint supply means is disclosed. The rotary painting assembly comprises a non-conductive body. A high speed, non-conductive turbine is connected to a non-conductive atomizer bell. In one embodiment, the non-conductive turbine is connected to a non-conductive rotatable shaft which mounts the non-conductive atomizer bell. In another embodiment, the non-conductive shaft is fixed. The non-conductive shaft rotatably mounts a non-conductive turbine and rotary atomizer bell assembly.
Abstract:
A rotary atomizer including a manifold assembly adapted to be attached to a mechanism for supporting and/or moving the atomizer and an air bearing turbine motor housing assembly releasably secured to the manifold assembly. Sources of pressured fluid for actuating the atomizer and coating fluid are connected to the manifold which has fittings for releasably sealing to apertures in the rear cover of the housing assembly. The opposite end of the housing includes a shaping air cap and a shaping air ring which cooperate to define an annulus for discharging a thin ring of shaping air over the peripheral edge of an atomizer bell to direct fluid particles toward a target. Exhaust air from the turbine motor is vented to the inside of the housing and directed to a chamber behind the atomizer bell to aid in directing the fluid particles. A magnetic speed pickup generates a signal which is coupled through a circuit that electrically isolates high voltage which is applied to the atomizer to electrostatically charge the coating particles.
Abstract:
An improved rotary paint atomizing device in the form of a bell and a cover plate which is releasably attached to the front center of the bell. Paint fed along the axis of the device onto a conical projection on the back surface of the cover plate accelerates and flows outward in a radial direction. The cover plate surface is curved so that as the paint flows outwardly, it also flows first forward and then back until it reaches radial slots formed in a peripheral rim on the cover plate where the cover plate contacts an interior bell surface. Paint discharges from the slots onto a conical interior bell surface and flows in wide, closely spaced ribbons which merge into a uniform, continuous thin sheet before it is discharged from the bell edge. As the paint discharges from the bell edge, the sheet produces extremely fine uniform ligaments which break up to produce fine, uniform small paint particles.
Abstract:
A rotary atomizer (20) includes a manifold assembly (22) adapted to be attached to a mechanism for moving the atomizer and an air bearing turbine motor housing assembly (21) releasably secured to the manifold assembly. Sources of pressured fluid for actuating the atomizer and coating fluid are connected to the manifold (29) which has fittings (32, 33, 34, 35, 36) for releasably sealing to apertures (42) in the rear cover (43) of the housing assembly. The opposite end of the housing includes a shaping air cap (24) and a shaping air ring (25) which cooperate to define an annulus for discharging a thin ring of shaping air over the peripheral edge of an atomizer bell (26) to direct fluid particles toward a target. Exhaust air from the turbine motor (46) is vented to the inside of the housing and directed to a chamber (79) behind the atomizer bell to aid in directing the fluid particles. A magnetic speed pickup (103, 104) generates a signal which is coupled through a circuit (105, 106) that electrically isolates the high voltage which is applied to the atomizer to electrostatically charge the coating particles.