Patent GB-386475-A (GB)
Title: Improvements in or relating to refrigerating apparatus
IPC: F25B17/00
Filed: 1932-03-17
Abstract: 386,475. Refrigerating. ELECTROLUX, Ltd., 153, Regent Street, London.- (Assignees of Knight, D. B. ; 209, Lincoln Place, Brooklyn, New York, U.S.A.) March 17, 1932, No. 7980. Convention date, March 18, 1931. [Class 29.] Absorption systems. - Liquefied refrigerant is transferred automatically and without the aid of moving parts from heat insulated relation with the medium to be cooled into heat-exchange relation therewith at a rate depending on the difference in temperature between the medium and the boiling-point of the refrigerant. An evaporator for such operation comprises an outer closed vessel 20 and an inner open-topped vessel 21, with an external conduit 23 rising from the bottom of the inner vessel, which may extend through the bottom of the outer vessel, to the top of the annular space. Liquefied refrigerant is fed through a pipe 18 to the annular space and overflows the opening of the inner vessel and fills the latter. When refrigeration begins the supply of heat from the medium to be cooled to the pipe 23 causes ebullition therein and transfer of refrigerant by a lifting action from the inner vessel to the jacket, which also is exposed to the medium to be cooled. The rate of transfer depends on the temperature of the external medium. The evaporator is particularly suitable for a reversing absorption system comprising a generator-absorber 11, a rectifier 14. and a condenser 15 above the rectifier. An open-bottomed shell 13 in the generatorabsorber is connected to the vapour expulsion conduit and rectifier, and may be heated by a flue or electric heating element 9. During the generating period the liquor is forced into the shell 13 and the generated vapour passes therethrough. In the absorption period the liquor is forced out of the shell 13 by the returning vapour. A separate closed-cycle condensing system for cooling the generator-absorber, rectifier and condenser comprises a jacket 12 around the generator-absorber, a conduit 24 connecting this jacket with a casing 17 around the refrigerating condenser 15, a condenser element 26 cooled by a water jacket 27, and a standpipe 31 extending the full height of the apparatus and connected at the top by a pipe 30 with the condenser element and at the bottom by pipes 32, 34 respectively with the jacket 12 and with a vessel 33 in contact with the rectifier. The closed system contains liquefied medium to the dotted-line level when the apparatus is idle. During the generating period liquid is forced from the jacket 12 up the pipe 24 to the casing 17, the standpipe acting as a seal against flow through the pipe 32. The medium evaporates in casing 17 and the vapour rises through pipe 25 to condenser element 26 and returns as liquid back to casing 17. The heat of rectification evaporates medium in vessel 33 and prevents flow from the standpipe to this vessel. At end of generating period the cool returning refrigerant condenses the medium in vessel 33, which is refilled from the standpipe, and the medium flows from the casing 17 back to the jacket 12. The heat of absorption expels vapour from the jacket through pipe 32 to the standpipe, whence it rises to the condenser element 26 and flows back through casing 17 and pipe 24.