GB393065A - Improvements in refrigerating machines - Google Patents

Abstract

393,065. Lubricating. ROGERS, F. H., 181, Queen Victoria Street, London.-(Getriebebau Ges.; 65, Saalmannstrasse, Reinickendorf - West, Berlin.) April 27, 1932, No. 12133. [Class 12 (iii).] In a compression refrigerating system the lubricating oil, not miscible with the refrigerant, drains to a single collecting point, auxiliary oil circulating means such as pumps being dispensed with. In the arrangement shown in Fig. 1, the oil is delivered with the refrigerant from the condenser 21 to the evaporator vessel 12, approximately at the line between the refrigerant and the oil floating thereon. The refrigerant vapour rises through an apertured tube 15 to the compressor crank case, which forms the suction chamber, and entrains oil with it, and any liquid refrigerant in the crank case passes back to the evaporator through a drain hole 18. The compressor is driven by an overhung electric motor 7 in a removable casing 3 sealed from the crank case by packing 8. A tube 9 filled with granular material connects the motor casing with the oil sump, and serves to drain any oil out of the motor casing. In another arrangement the evaporator forms an unrestricted extension of the crank case and the crank may dip into the floating oil or may be fitted with dipping chains or rings. In a further construction, Fig. 3, the evaporator 24 traversed by tubes 26 is separated by a partition 29 from the crank case, or may be at some distance from it, and the U-shaped vapour suction tube 30 is provided with an enlargement 33 at its lowest part. Lubricant floating on the refrigerant passes through a filter 32 filled with granular material and flows in drops into the widened portion of the suction tube, where the speed of the vapour is reduced so that it cannot entrain an excessive amount of oil. The oil nozzle may be interchangeable to alter the sizes of the drops. Oil flows back from the crank case through a tube 38, which may be straight or, preferably, bent as shown to form a siphon. The arrangement may be employed with lubricant heavier than the refrigerant. Reference has been directed by the Comptroller to Specifications 150,017 and 165,968, [both in Class 29, Cooling &c.].