Patent GB-864567-A (GB)
Title: Ice making machine
IPC: F25C1/12
Filed: 1958-03-17
Abstract: 864,567. Ice-making. BORG-WARNER CORPORATION. March 17, 1958 [April 1, 1957], No. 8542/58. Class 29 Ice-block making apparatus comprises a vertical trough the side walls of which make each an angle of more than 90 degrees with the base, means for causing a stream of water to flow down the trough, a refrigerant evaporator in contact with the trough at places spaced therealong so that an ice-block is formed at each place, and means for releasing the blocks from the trough so that they fall freely down into a collecting bin. As shown in Fig. 7, two banks of troughs having bases 44 and side walls 45 are disposed face to face and are each formed from a sinuous metal strip. Thus vertical channels 46 of hexagonal cross-section are formed. In a modification (Fig. 8, not shown) the channels are formed by vertical side-by-side pipes each of hexagonal cross-section. To restrict ice formation to the places where the evaporator contacts the troughs the latter are made of a metal of poor heat conductivity e.g. stainless steel. The evaporator coil 37 passes in spaced horizontal runs up one side of the trough assembly, down to the bottom of the other side, and then up the said other side in spaced horizontal runs. Each run is connected to the bases 44 of the troughs. A water tank 51 is located beneath the trough assembly and water is withdrawn therefrom by a pump 52 which supplies it through pipe 54 to a top header 55. Pipes 56 convey water from header 55 to distributers (not shown) in the tops of channels 46 and the water runs down the troughs to be frozen in blocks on the bases thereof. Unfrozen water runs from the bottom of channels 46 back into tank 51. Some water runs from header 55 through pipe 61 to a control tube 34 the wall of which is refrigerated by a part 33 of the evaporator. Ice 118 thus forms in the tube 34, unfrozen water draining to tank 51, and when this ice blocks tube 34, the incoming water backs up and flows along pipe 71. The diameter of tube 34 is so chosen that this occurs when the blocks formed in the troughs are of the required size. The cold water in pipe 71 actuates a thermal element 85 to stop pump 52 and to open a valve 42 in pipe 41. Thereupon, hot gas flows through pipe 41 from compressor 17 to the evaporator sections 33, 37, the ice blocks in tube 34 falling into tank 51 to melt and the blocks falling from the troughs on to a grid (not shown) which diverts them into bin 11. Since evaporator 37 runs from the bottom to the top of each side of the trough assembly the lower blocks are released first thus preventing jamming. When all the blocks have been released, the gas leaving the evaporator 37 is warm and this causes a thermal element 81 on the suction pipe 39 to close hot gas valve 42 and put into operation water pump 52 thus starting a fresh cycle. However, if the previous cycle had filled bin 11 with blocks, the resultant low temperature causes thermal bulb 89 in the bin to open a main switch 88 thus shutting down the whole machine. A condenser fan 24 is also inactive during the ice-releasing phase. To prevent accumulation of impurities in the circulating water, some of the water leaving tube 34 runs down an angled bar 76 into a drain 78. By varying angle B or by using a different diameter of bar, the amount of water drawn off can be varied. Specification 864,568 is referred to.