Abstract:
A diffuser (518) comprises a conduit having a cross-sectional area that increases in a direction fluid flow. In one embodiment, the diffuser is used to reduce the incidence and severity of flow fluctuations that occur in an electrostatic deposition apparatus. In some embodiments, the diffuser includes one or more flow control features. A first flow-control feature comprises one or more appropriately-shaped annular slits (520) through which fluid having a greater momentum than a primary fluid moving through the diffuser is injected into the "boundary layer" near the wall of the diffuser. A second flow control feature comprises one or more annular slits (548) or, alternatively, slots or holes that are disposed at appropriate locations around the circumference of the diffuser through which a portion of fluid flowing in the boundary layer is removed. Boundary-layer flow removal is effected, in one embodiment, by creating a pressure differential across such annular slit or slots. Among other benefits, such flow control features reduce any tendencies for flow separation of the primary fluid in the diffuser.
Abstract:
The present invention provides a product (1) that includes a pharmaceutical unit dosage or diagnostic form (6) that includes at least one active ingredient that is present in an amount that advantageously does not vary by more than about five percent from a predetermined target amount. In one embodiment, the unit form comprises a substrate (8), a deposit (14) that is disposed on the substrate and a cover layer (9) that overlies the deposit and is joined to the substrate by a bond that encircles that deposit, thereby encapsulating it between the substrate and cover substrates. The deposit comprises a powder, at least some of which includes the at least one active ingredient. The unit form is created via a dry powder deposition apparatus that electrostatically deposits the powder on the substrate utilizing an electrostatic chuck and charged powder delivery apparatus.
Abstract:
Provided is an electrostatic sensing chuck for attracting particles to a portion of a particle contact surface near a deposition electrode, the electrostatic sensing chuck comprising a pixel comprising: a deposition electrode (DE) for selectively establishing an attraction field (Ea) at the particle contact surface; a shield electrode (SE) oppositely biased with respect to the deposition electrode; a charge sensing circuit to measure charge accumulated on each of the deposition electrode and the shield electrode, wherein the charge sensing circuit subtracts a second charge it senses at the shield electrode from a first charge it senses at the deposition electrode, thereby determining accumulated charge at the deposition electrode balanced by accumulated charge at the shield electrode.
Abstract:
The present invention provides a product (1) that includes a pharmaceutical unit dosage or diagnostic form (6) that includes at least one active ingredient that is present in an amount that advantageously does not vary by more than about five percent from a predetermined target amount. In one embodiment, the unit form comprises a substrate (8), a deposit (14) that is disposed on the substrate and a cover layer (9) that overlies the deposit and is joined to the substrate by a bond that encircles that deposit, thereby encapsulating it between the substrate and cover substrates. The deposit comprises a powder, at least some of which includes the at least one active ingredient. The unit form is created via a dry powder deposition apparatus that electrostatically deposits the powder on the substrate utilizing an electrostatic chuck and charged powder delivery apparatus.
Abstract:
Provided is an electrostatic sensing chuck for attracting particles to a portion of a particle contact surface near a deposition electrode, the electrostatic sensing chuck comprising a pixel comprising: a deposition electrode (DE) for selectively establishing an attraction field (Ea) at the particle contact surface; a shield electrode (SE) oppositely biased with respect to the deposition electrode; a charge sensing circuit to measure charge accumulated on each of the deposition electrode and the shield electrode, wherein the charge sensing circuit subtracts a second charge it senses at the shield electrode from a first charge it senses at the deposition electrode, thereby determining accumulated charge at the deposition electrode balanced by accumulated charge at the shield electrode.
Abstract:
Provided is an electrostatic sensing chuck for attracting particles to a portion of a particle contact surface near a deposition electrode, the electrostatic sensing chuck comprising a pixel comprising: a deposition electrode (DE) for selectively establishing an attraction field (Ea) at the particle contact surface; a shield electrode (SE) oppositely biased with respect to the deposition electrode; a charge sensing circuit to measure charge accumulated on each of the deposition electrode and the shield electrode, wherein the charge sensing circuit subtracts a second charge it senses at the shield electrode from a first charge it senses at the deposition electrode, thereby determining accumulated charge at the deposition electrode balanced by accumulated charge at the shield electrode.
Abstract:
Provided is, among other things, and together with associated methods, a powder feed apparatus including a venturi (120) with an external gas inlet, a gas outlet, and an internal gas inlet, a cyclone (130) with an intake port connected to the gas outlet, a recycle outlet port, and a product port.
Abstract:
Provided is a re-circulating particle feed apparatus (10) comprising: a circular conduit (11) suitable for circulating gas suspended particulates; a deposition station (17) comprising an opening onto the conduit into which an electrostatic chuck fits, with a deposition surface of the chuck (9) fits, a nd a propulsion device (12) for maintaining gas and particle circulation throug h the conduit (11), wherein the device (12) is adapted to maintain circulation at a rate that brings a deposition effective amount of particles within a range of electro-attractive influence at the deposition station (17).
Abstract:
Provided is, among other things, and together with associated methods, a powder feed comprising: a venturi comprising an external gas inlet, a gas outlet through which gas flows at a rate amplified over a gas flow rate into the external gas inlet, and an internal gas inlet; and a cyclone with an intake port connected to the venturi gas outlet, a recycle outlet port, and a product port, wherein a gas flow rate FS into the venturi external gas inlet results in an enhanced flow rate into the cyclone intake port.
Abstract:
Provided is, among other things, and together with associated methods, a powder feed comprising: a venturi comprising an external gas inlet, a gas outlet through which gas flows at a rate amplified over a gas flow rate into the external gas inlet, and an internal gas inlet; and a cyclone with an intake port connected to the venturi gas outlet, a recycle outlet port, and a product port, wherein a gas flow rate FS into the venturi external gas inlet results in an enhanced flow rate into the cyclone intake port.