Device for the controlled feeding of powder material
US4381898A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 1981 |
| Grant date | May 3, 1983 |
| Priority date | — |
| Expiry date | Jan 21, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/42
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The invention contemplates a powder-feeding system for gas-propelled delivery of a powder to be controllably supplied, as to a flame-spraying gas torch or to a transferred-arc plasma torch. A fluidizing chamber receives (a) fluidizing-gas flow from below a porous screen, and (b) a restricted gravitational flow of powder at a relatively small central discharge location above the porous screen. A gas conduit extends transversely through the chamber between the powder-discharge location and the porous screen; it has a carrier-gas supply connection at one end and a gas-propelled powder-delivery connection at its other end. The conduit also has an upwardly extending opening virtually beneath and facing the powder-discharge location, but a shed interposed between this opening and the powder-discharge location sufficiently overlaps the opening to assure that no powder will pass through the opening and into the conduit unless it has been gas-fluidized. The powder-discharge flow is blocked to gas flow when powder is being delivered by the carrier-gas flow, but the powder delivery is terminated promptly upon gas-venting the fluidizing chamber, via the powder-discharge flow or otherwise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.