769312-A is referenced by 2 patents.

769,312. Helical shoots. QUALTER, HALL & CO. (SALES), Ltd. Feb. 15, 1955 [Nov. 16, 1953], No. 31768/53. Class 78 (1). A helical bunkering shoot consists of an upright open helix having a peripheral angle of between 25 degrees, 30 minutes and 28 degrees, 30 minutes to the horizontal and wherein the slope of the track face nearer the axis of the shoot is between 38 degrees and 46 degrees measured in a radial section and with regard to the horizontal. As shown, the shoot is made in sections A having a flange B and being braced by stiffening ribs C, the whole being secured at flange B to a supporting scroll (not shown).

Improvements in helical chutes primarily for bunkering coal
Application Number
GB19530031768 19531116
Publication Number
769312 (A)
Application Date
November 16, 1953
Publication Date
March 6, 1957
Hall Thomas
Qualter Hall & Co Sales
B65G 11/00
B65G 11/06
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