GB441737A - Improvements in, or relating to, closure members for valves or gates - Google Patents

Abstract

441,737. Shoots and hoppers. FLOOD, W. H., 50, Ecclesall Road South, Sheffield. Jan. 19, 1935, No. 1890. [Class 78 (i)] [See also Group XXIX] A valve or gate for controlling the passage of materials of widely differing consistency comprises a flexible closure member or apron 20 which is progressively stripped from the valve seat to open the valve by contact with a supporting roller 10 having a translatory movement across the valve seat, the area of the apron which is in contact with the roller 10 changing progressively but remaining the same in extent. In Fig. 1, the valve seat is formed at the base of a hopper 2 mounted in a frame 3 provided at each side with anti-friction rollers 5 to support a carriage comprising a plate 4 and angle irons 7. The roller 10, two pulleys 13 on a common shaft 12, and a series of intermediate supporting rollers 25 are mounted on this carriage which is reciprocated as a unit by a rack 14 and pinion 15 the shaft of which is operated by a chain and a sprocket wheel. One end of the apron is fixed to a stationary bracket 21 and the other end to two cables passing over the pulleys 13 and connected to adjustable bolts 23. The apron may be of leather or other flexible material or may consist of ropes, metallic chains or small articulated links in which latter case the roller 10 is of polygonal cross-section. To avoid fouling the edge of the valve seat in the final closing movement, an opening may be formed in the seat and the apron and carriage constructed to project beyond the seat so allowing material passing through the opening to rest on the apron at its angle of repose. In a modification the rollers 5 are replaced by suitable wheels, rollers or skids mounted on the carriage for engagement with guideways on the frame 3. In this form, the pulley shaft 12 has eccentric spigots adjustably clamped in the frame for tensioning the apron. In a further modification, Fig. 8, two hoppers 31, 32 are controlled by a single apron 20 so that only one can be opened at once. Both ends of the apron are anchored at 39, 40 intermediate the hoppers. The apron passes over supporting rollers 37, 38 at the ends of a carriage fitted with wheels 33. The sides 42 of the hopper may be of flexible material such as rubber or leather. According to the Provisional Specification, the apron may be of rubberized fabric or balata, and the cables may be dispensed with, an endless belt anchored at one point being used instead.