US 4,399,906 A · Temperature expansive screw conveyor

Abstract

A screw conveyor (10) is disclosed for use in environments having a large range of temperature. The screw conveyor (10) includes a hollow shaft (12) having a number of aligned circular holes (18a, 18b) therein, with adjacent sets of holes being at right angles to each other. A stake (16) is slidably inserted in each set of holes (18a, 18b) for securing a helical flight (14a-e) to the shaft (12). Four stakes (16) are welded to the back (26) of each of the helical flights (14) along a helical line corresponding to the helical path defined by the flights (14). The slidable interaction of the stakes (16) with respect to the shaft (12) permits each flight (14) to move relative to the shaft (12) during expansion or contraction of the screw conveyor (10). The back peripheral edge (20) and front peripheral edge (22) of adjacent helical flights (14) are overlapping and movable with respect to each other to further accommodate the expansion and contraction of the screw conveyor (10).

Claims14

Dependent claims

A screw conveyor for conveying material comprising:

shaft means mounted for rotation about an axis and having holes formed therein, each of said holes being positioned at a predetermined angle from the next adjacent hole;
a plurality of stake means slidably inserted in said holes and extending generally outward from said shaft means;
a plurality of adjacent flights having a trailing edge and a leading edge with a continuous helical contour therebetween positioned about a portion of said shaft means for conveying material as said shaft means is rotated, the trailing edge of each of said flights slideably overlapping the leading edge of the adjacent one of said flights, each of said flights secured to selected ones of said stake means so that each of said flights and said selected ones of said stake means can move relative to said shaft means during expansion and contraction of the screw conveyor.

A screw conveyor for conveying material comprising:

an elongate central shaft mounted for rotation about an axis having holes formed therein, each of said holes being positioned at essentially ninety degrees from the next adjacent hole;
a plurality of stakes slidably inserted in said holes and extending outwardly from said shaft;
a plurality of adjacent flights having a trailing edge and a leading edge with a continuous helical contour therebetween positioned about a portion of said central shaft for conveying material as said central shaft is rotated, the trailing edge of each of said flights slideably overlapping the leading edge of the adjacent one of said flights, each of said flights secured to selected ones of said stakes with one of said stakes disposed proximate the surface of the leading edge of an associated one of said flights to support both the leading edge of the associated one of said flights and the overlapping edge of the adjacent one of said flights, the overlapping of said flights accomodating the relative movement between each of said flights, and said central shaft during expansion and contraction of said screw conveyor.

A screw conveyor for conveying material comprising:

an elongate central shaft mounted for rotation about its elongate axis and having a plurality of holes formed therethrough generally perpendicular to the axes of rotation, each of said holes being positioned along said central shaft at right angles to the next adjacent hole;
a plurality of stakes slidably inserted in said holes and extending outwardly from said central shaft perpendicular to the axis of rotation;
a plurality of adjacent helical flights having a leading edge and a trailing edge with a continuous helical contour therebetween for conveying material along said central shaft as said central shaft is rotated, each of said flights being positioned about a portion of said central shaft and dimensioned to circumvent said central shaft more than one revolution thereof, each of said flights secured to selected ones of said stakes with one of said stakes disposed proximate the surface of the leading edge of an associated one of said flights to support both the leading edge of the associated one of said flights and the overlapping edge of the adjacent one of said flights, adjacent ones of said flights slidable overlapping so that the expansion and contraction of the screw conveyor is accommodated by the relative motion of each of said flights and said selected ones of said stakes relative to said central shaft, each of said flights substantially retaining said stakes in said holes and said stakes substantially retaining rotational motion of each of said flights about said shaft.

Dependencies are inferred from the claim text.

Temperature expansive screw conveyor

Life of this patent

Temperature expansive screw conveyor

Life of this patent

Abstract

Claims14