Patent GB-693033-A (GB)
Title: Improvements in or relating to absorption type refrigerating apparatus
IPC: F25B15/10
Filed: 1949-03-16
Abstract: 693,033. Refrigerating, heat-exchange elements. KONDZIOLKA, E. June 13,1950 [March 16,1949; April 11, 1950], Nos. 7230/49 and 8894/50. Classes 29 and 64 (iii)] The Specification describes improvements in the generator, condenser, evaporator, gas-heat exchanger, absorber, liquid-heat exchanger, rectifier and thermostatic control of a continuous cycle absorbtion refrigerating system of the inert gas type. Liquid-heat exchanger (Figs. 1 and 9). Weak liquor from the generator flows through a pipe 4 through a part 5 from which it flows through an inner tube 6 and a pipe 34 to the absorber 31. Strong liquor from the absorber vessel 30 flows through a pipe 32 to a tube 8 surrounding the tube 6 and then to a part 7 in heat exchange with which the part 5 whence it flows to the generator. The parts 5 and 7 are formed as a single pipe divided by a longitudinally corrugated partition 33 to provide an enlarged common surface. Generator (Figs. 1 and 12). A flue tube 1 is heated by a burner 2 and the pump coil 3 surrounds the flue and pumps solution to the upper part 10 of the boiler 11 which surrounds the flue. The lower part of the boiler is insulated from the heat source by insulation 38 and a baflle 39 is provided in the flue to concentrate the heat at the upper part of the boiler. The flue 1 is insulated from the generator casing 36 by an insulating member 37. In Fig. 12, the coil 3 is heated by an electric heater 52, and the boiler by an electric heater 51 at the upper part, the flue being filled with insulation and having a top cap 54. Rectifier (Figs. 1 and 10). The upper part 10 of the boiler contains cups 14 both below and above the entry of the gas-bubble pump riser pipe. These cups have conical lower parts provided with a bottom opening 15 for liquid and a higher opening 16 for ascending gases. The upper part of the conduit 10 is surrounded by a cooling coil 17 in a closed circuit containing aqueous ammonia and comprising a jacket 9 round the liquid heat exchanger, a riser 20, the coil 17, a small tank 18 and a down-pipe 19. Heat from the liquid-heat exchanger maintains the circulation and the cooling in the coil 17 is because the heat of the boiler vapours vaporizes ammonia from the solution in the coil. Evaporator (Figs. 1 and 3). The evaporator 24 comprises a flat casing divided by a longitudinal partition 25 extending nearly the length of the casing. Liquid refrigerant from the condenser 21 enters the evaporator by a U-pipe 23 in proximity to the entry pipe 28a for the inert gas, the gaseous mixture leaving by a pipe 26 on the other side of the partition 25. The evaporator carries depending side plates 45 fitted with vertical fins 46. One or more ice-tray supports 46a may be provided. Gas-heat exchanger (Figs. 1 and 6). The gaseous mixture from the evaporator passes through the outer tube 27 of a concentric tube gas-heat exchanger through the eccentric inner tube 28 of which the inert gas flows. The tube 28 is provided with internal and external baffles formed of sheets 50, 47 having presses out parts 49, 48 and bent to C-shape for insertion in the tubes 28, 27. These baffles control the gaseous flow. According to the first Provisional Specification, the baffles within the tube 28 may be formed as slotted discs having peripheral flanges and inserted into the tube where they are a press fit. The external baffles are in the form of C-shaped fins welded on to the tube 28, alternate fins being spaced 180 degrees around the tube 28. Control and reversing absorption system (Fig. 1). To prevent short-cycling of a thermostatic control of the heat source, part of the condenser 21 is jacketted by a container 43 containing a dry absorbent 44 from which ammonia is generated during operation of the heat source, the ammonia passing through a condenser 42 to a receiver 41 connected to an auxiliary evaporator 40 situated close to the main evaporator 24. When the heating is cut off by the thermostat the condenser 21 cools and the absorbent 44 starts absorbing to evaporate refrigerant in the evaporator 40 and thus the temperature in the space to be cooled rises more slowly than normal and the thermostat cycle is longer. The absorber vessel 30 and the lower part of the finless absorber coil 31 may be heat insulated.