Patent GB-360543-A (GB)
Title: Improvements in refrigerating machines of the absorption type
IPC: F25B17/02
Filed: 1930-09-01
Abstract: 360,543. Refrigerating. DAHLGREN, S. A. B., 33, Nockebyvagen, Alsten, Sweden. Sept. 1, 1930, No. 26058. Convention date, Sept. 3, 1929. [Class 29.] Absorption machines and systems.-The circulation of refrigerant vapour between the absorber and the evaporator of machines using an inert gas, e.g. nitrogen, is effected by the pumping action of absorption liquid and without the use of valves or liquid seals between the evaporator and the absorber. In the case of an intermittently-acting rotary reversing machine comprising a generator absorber A, Fig. 1, and an evaporator condenser B connected by circulation tubes C, D of which one end of the tube C is secured to a partition W, having tubes K either of small diameter or packed with porous material so as to be always full of liquid and permit absorption liquid only to flow from the compartment H to the compartment G, the refrigerant vapour generated in the part G of the generator absorber is pumped, together with inert gas, through the spiral tube I into the compartment H by liquid picked up by that part of the tube in the compartment G during the rotation of the machine. From the compartment H, the mixed vapour and gas pass to the water-cooled evaporator condenser in which the vapour condenses while the gas returns through the tube D to the compartment G. At the end of generation, the supply of cooling water is diverted by a three-way valve T from the tank L to the tank M which, during generation, is heated by a gas burner. The machine may be driven by a spring or electrically-operated motor or a turbine operated by the cooling water. If the machine is air-cooled, both the machine and the air fan may be driven by an electric motor. In a continuously-acting rotary machine comprising an absorber 1, Fig. 5, connected by circulation tubes 4, 5 to an evaporator coil 2 and by a tube 6, closed at the absorber and, to the generator 3, the circulation of the vapour and inert gas is effected by the spiral tube 14, while the spiral tubes 16, 18 transfer weak and strong liquor from the generator to the absorber and from the absorber to the generator respectively. The vapour from the generator flows into the tube 6 and thence through the coil 17 to the condenser coil 7 from which the condensate passes through the pipe 8 to the evaporator coil. A modified machine comprises a generator absorber a, Figs. 3 and 4, and an evaporator condenser b, connected by circulation pipes c, d and oscillatably supported in bearings, the pumping being effected by the oscillation of the absorption liquid on either side of a partition k in the generator absorber. A continuously-acting machine having no moving parts comprises essentially a generator 27, Fig. 6, condenser coil 39, evaporator 26 and absorber 25, the absorber being divided into superposed compartments connected to one another by siphons 30 and to the evaporator by tubes 31. In use, the refrigerant vapour flows from the generator through the water-cooled rectifier 38 to the condenser coil 39 to the evaporator in which it cascades over the dishes 32, while the weak absorption liquid passes through the tube 37, the lower portion of which is immersed in relatively cool strong absorption liquor in the tanks 34, 35, to the uppermost compartment of the absorber. The rise of the liquid level in this compartment forces the inert gas through the tube 31 into the evaporator wherein it becomes rich in refrigerant vapour and, upon the liquor in the uppermost compartment being siphoned into the compartment beneath it, is drawn back into the uppermost compartment and its vapour component is absorbed by fresh weak liquor from the generator. A similar action takes place in each of the compartments, the strong liquor passing through the tube 33 into the tank 34 and thence to the tank 35 from which it flows through the pipe 36 to the generator. The absorber is cooled bv a cold water conduit 41 which also encloses the pipe 37. In a modification, perforate dishes are placed in the absorber compartments into which the siphons discharge.