Patent GB-348020-A (GB)
Title: A new or improved gear pump
IPC: F04C15/00
Filed: 1930-01-31
Abstract: 348,020. Lubricating gear - wheel pumps. O'CONNELL, J., 33, Barton Arcade, Manchester.-(McIntyre, F. ; 249, Highland Street, West Newton, Massachusetts, U.S.A.) Jan. 31, 1930, No. 3306. [Class 12 (ii).] The gears and shafts of a gear-wheel pump for artificial silk spinning are lubricated by the cellulose being pumped, and the driving means and external shaft lubricated by oil. A sealing disc separates the two systems of lubrication but allows the passage of the shaft to drive the pump. Cellulose trapped by meshing teeth escapes by way of grooves which lead to the shaft bearings. Gearwheels 17, 18 fit closely to chambers in a ground steel plate 13 which is clamped between two cast iron plates 11, 12. A toothed driving-wheel 40 is fixed by a strap 46 to a tongue-piece 47 on an external driving-shaft 42 and the latter is connected to an inner shaft 41 by means of a tongue 43. The wheel 40 is retained in position by a plate 48 screwed to a cover 39 which extends axially to a sealing disc 55 which separates the two lubricating systems. The driving shaft 27 of the pump has a tongue-piece 33 which fits in a slot of a loose disc 35 on the periphery of which are two notches. Driving dogs 45 which extend from a flange 44 on the shaft 41 engage these notches and thus drive the shaft 27. Plugs 30 seal up the other three ends of the shafts 27, 28 and are packed by washers to prevent evaporation of the volatile constituent of the cellulose which is forced by the action of the pump into chambers at the ends of the shafts 27, 28. Shallow grooves lead from the inlet side of the pump at a point where the meshing teeth are just separating, to the shaft bearings and cellulose is forced upwards by the gears. Return passages lead the lubricant to the inlet side of the pump. A quantity of lubricant passes by way of a passage 33 to a cavity 98 at the end of the driving shaft and enters holes 64 in the flange 44 and lubricates the surfaces of this flange and the sealing ring 55 which are pressed together by the cellulose in the cavity 98. A hole 51 is provided for entry of oil to passages 52, 53, 54 and to the outside of the sealing plate 55. A recess 65 in each plate 11, 12 allows solution trapped in the meshing teeth to escape outside the meshing point. Grooves may lead from the meshing point to enable trapped solution to be forced by the mating teeth to the shaft bearings and return passages lead the solution to the outlet side of the pump. Fig. 10 shows an alternative driving shaft 72 which replaces the two shafts 41, 42. A duct 80 leads cellulose to the shaft bearing surface and lubricates the surface of cork packing with which the stuffing-box 78 is filled. The flnge 44a contains holes which allow cellulose to lubricate the surfaces of the flange and the washer 79. In another modification cellulose trapped in the teeth may be led through radial holes which are drilled from the roots of the teeth to a groove which is open to the shaft bearing surfaces. In Fig. 11 the solution enters a port 83 and flows to spaces at the ends of hollow shafts 27, 28, which carry gears 19, 20, and is discharged through a port 88. Specification 296,791, [Class 110 (ii), Rotary engines &c.], is referred to.