GB691197A - Improvements in or relating to methods and apparatus for producing and harvesting ice blocks - Google Patents

Abstract

691,197. Ice-making. WILBUSHEWICH, E. June 5, 1950, No. 13985/50. Class 29. An ice-making machine operating on a freezing and harvesting cycle comprises one or a battery of vertical ice-making moulds 1 enclosed in an evaporator casing 6 and provided each with a separate swingable bottom 4, pivoted at 3 and provided with counterweights 5, the bottom 4 being caused to adhere to the mould by the freezing of residual moisture but the weight of the ice being sufficient to overcome the weight 5 during harvesting. The thawing or harvesting phase is initiated by a thermostat bulb 15 so positioned as to be above the liquid level in one mould but to be contacted by the unfrozen liquid containing dissolved impurities when the bulk of the water has been frozen. The thermostat operates a valve 22 which supplies gaseous refrigerant at condenser pressure to the evaporator 6. When the bottom 4 swings open it contacts a switch 16 to terminate the thawing phase, the discharged iceblock falling on to a chute 18 provided with a resiliently mounted braking member 21 and an end-stop 20. The bottoms then swing back to closing position and are held there by freezing. When the temperature has dropped sufficiently a thermostatic element 17 operates a valve 14 to admit a fresh charge of water from a tank 9 which may be fitted with a ball-cock. The valve 14 may again be shut by thermostatic control. The moulds 1 may have removable lids 10. In modification the weight 5 may be replaced by a spring or the thermostats may be replaced by time-switches.