Conveyors: power-driven – Conveyor section – Flight means in conduit for lifting flowable solid material
Reexamination Certificate
2000-03-07
2001-07-31
Ellis, Christopher P. (Department: 3651)
Conveyors: power-driven
Conveyor section
Flight means in conduit for lifting flowable solid material
C198S359000, C198S360000, C198S370010, C198S735300, C198S860400
Reexamination Certificate
active
06267227
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to conveyors for particulate material and more especially to relatively slow speed drag conveyors and aero mechanical conveyors.
2. Related Art
Slow speed drag conveyors and aero mechanical conveyors are of tubular construction and include a tensioned wire rope or chain to which are fitted a plurality of spaced plastics discs running between terminal sprockets. These conveyors operate at relatively slow speeds and effectively drag particulate material along the conveying tubes to a selected outlet valve. Throughputs of the order of between 8 and 32 m
3
per hour are typical. The tubes of the conveyor may be aligned horizontally, vertically or may be inclined.
Products commonly handled by such conveyors include tea, sugar, detergents, flour, seeds, granules, gypsum, polymer powders and resins and the conveyors are used extensively in the food, pharmaceutical and chemical industries.
The presence of the wire rope discs or chain discs within the tubes places severe constraints on the position and operation of outlet valves. It is possible to use butterfly and slide valves as outlet valves; generally, however, they are unacceptable and have severe design disadvantages.
Rotatable valves have also been proposed in the past, but have been relatively expensive and susceptible to damage because of particulate material becoming trapped between abutting and stationary members of the valve and conveyor tubes. A rotatable valve for metering the flow of a stream of pneumatically conveyed dry particulate material such as cement is disclosed in U.S. Pat. No. 5,174,320.
U.S. Pat. No. 3,586,155 discloses a tubular conveyor assembly with spool-shaped conveyor flights. These are pulled through a tube by an endless cable driven by a sprocket wheel. Material leaves the assembly through a rotatable valve.
It is an object of this invention to provide an improved rotatable valve for tubular conveyors which does not suffer from or at least alleviates many disadvantages of existing valves.
BRIEF SUMMARY OF THE INVENTION
According to the present invention in one aspect there is provided a tubular conveyor assembly comprising a plurality of conveyor tubes through which one or more members are drawn to transport particulate material therethrough, the assembly including a tubular valve positioned with its longitudinal axis generally in line with the direction of flow of material through the valve, and means for imparting rotation to the valve relative to neighbouring conveyor tubes, at least one elongate aperture formed in the tubular valve through which particulate material can leave the assembly and means for sequentially rotating the tubular valve about its longitudinal axis between positions in which the at least one aperture is in the open or closed position of the valve, the conveyor being characterised in that the rotation imparting means comprises an air cylinder operable to impart linear movement to a gear rack which meshes with and imparts rotational movement to an annular gear wheel carried by the tubular valve.
A seal is preferably positioned between rotating and stationary members of the assembly to prevent the ingress of particulate material therebetween. This seal may comprise an “O” ring seal.
REFERENCES:
patent: 2147199 (1939-02-01), Hapman
patent: 3001633 (1961-09-01), Heitshu
patent: 3223228 (1965-12-01), Ferris et al.
patent: 3256862 (1966-06-01), Patterson
patent: 3279592 (1966-10-01), Kerkvliet
patent: 3575306 (1971-04-01), Obermeyer
patent: 3586155 (1971-06-01), Heitshu
patent: 5147029 (1992-09-01), Wadell
patent: 5174320 (1992-12-01), Allen
patent: 5267672 (1993-12-01), Jacobsen et al.
patent: 5526920 (1996-06-01), Ellsworth
patent: 725 140 (1942-07-01), None
patent: 2940253 (1981-04-01), None
patent: 397 271 (1990-11-01), None
patent: 743394 (1956-01-01), None
Bacon & Thomas PLLC
Ellis Christopher P.
Entecon Limited
Tran Khoi H.
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