GB982310A - Washing process for drum washing machines - Google Patents

Abstract

982,310. Washing machines. CONSTRUCTAWERKE G.m.b.H. April 25,1961 [April 25,1960], No. 14901/61. Heading D1A. In a washing machine comprising a drum rotatable about a horizontal axis the laundry is heated in detergent-containing washing liquid, which raised to its boiling point, and the drum is rotated intermittently for short periods whilst the liquid is maintained at its boiling point, the speed of rotation during said periods being only sufficient to tumble the laundry. As shown in Fig. 1, during a period t 1 the drum is rotated at a speed M whilst it is charged with cold water. Thereafter, during a period t 2 , the water is heated to 100‹C. and during a period t 3 the drum is rotated intermittently for periods #t e.g. 2 to 5 seconds at intervals of 1 to 2 minutes, whilst the temperature of the liquid is maintained at 100‹C. During periods #t the peripheral speed of the drum may be 0. 5 m/sec or less. In a subsequent period t 4 the drum is rotated at a high speed e. g. between 1 and 1. 5 m/sec, heating of the liquid being discontinued. The washing process is completed by alternate centrifuging and rinsing for periods t 5 , t 6 , respectively. During period t 1 the drum may be rotated first in one direction and then in the other direction, and during period t 2 the drum may be rotated intermittently. In a modification of the washing process. (Fig. 2, not shown) dirty liquid escapes through an overflow whilst the laundry is being wetted and during the first part of the period in which the liquid is heated.