Patent GB-632439-A (GB)
Title: Ice freezing apparatus
IPC: F25C1/06
Filed: 1947-05-31
Abstract: 632,439. Ice-making; ice-cutting machines. KUBAUGH, B. F. May 31, 1947, No. 14481. Convention date, April 12, 1939. [Class 29] [Also in Group XXIII] In ice-making apparatus comprising a battery of evaporators operating consecutively to deliver a substantially continuous supply of ice by gravity to a cutter and adapted to be supplied with hot compressed gas to free the ice, the supply of hot gas, the suction from each evaporator, the supply of water to be frozen and a supply of thawing water to free the ice from the lower ends of the evaporators are controlled by automatically operated valves. Each evaporator 3 comprises a vertical cylinder 5 closed by end plates 6, 7 and containing a bundle of tubes 18 fed with water from a top chamber 19 through ferrules 20, said tubes extending through the end plate 7 into a chamber formed in a casing 43 by a shear plate 27 beneath which is located a rotary motor driven cutter 47, Figs. 5 and 6. The cutter 47' comprises a helical plate 46 on a vertical axis 48. Water entering the ferrules 20 flows down the inner walls of the tubes 18, some being frozen and the residue escapes through holes 26 in the plate 27 to chutes 28 whence it falls to a tank 32 by way of screens 29 and troughs 30. It is then pumped back to the chamber 19 by way of a pump 33, a solenoid operated valve 61 and a pipe 25. When freezing has been completed, the valves 61 are closed, hot gas is introduced into the evaporator and thawing water to the space between the plates 7 and 27 to free the sticks of ice which drop on to the cutter 47 through the holes 26 and the pieces pass to a helical conveyer 55 by way of the chutes 28 and screens 29. A new freezing cycle is then started. A compressor 8 and condenser 11 supply liquid refrigerant to an accumulator 12 from which liquid refrigerant flows to the evaporators 3 connected in parallel by pipes 13. A main suction conduit 9 is connected to the evaporators by branches 10 each containing a solenoid operated valve 38. Hot gas is fed to the evaporators by conduit 37 and branches 39 each containing solenoid-operated valves 40. Thawing water is supplied to the lower ends of the evaporators by a conduit 59 and branches 45 each containing a solenoid-operated valve 60. The bottom of each evaporator 3 is connected to the top of the next succeeding one by a pipe 41 containing a solenoidoperated valve 42. If, in Fig. 9, the lefthand evaporator is about to discharge its ice and the next evaporator has just discharged its ice, the conditions are, for the first evaporator, valves 38, 61 open and valves 40, 42 and 60 closed and, for the next evaporator, the reverse. To discharge the first evaporator these conditions are reversed. This in the first evaporator shuts off the freezing water supply and suction and admits hot gas which drives all the liquid refrigerant over to the second evaporator by way of pipe 41 and frees the ice in the first evaporator which is then discharged. The consecutive operation of the valves 38, 40, 42, 60, 61 is controlled by an electric time-switch (Fig. 8, not shown). The freezing temperature and the thawing temperature are controlled by valves 70, 69 respectively.