| 摘要 |
1,019,703. Refrigerating. SULZER BROTHERS Ltd. May 3, 1963, [May 4, 1962] No. 17642/63. Heading F4H. In a close-cycle compression refrigeration system a vessel of constant volume is selectively connectible to either the suction or discharge line of the compressor. All parts of the system are designed to withstand a pressure greater than that of the non-circulating refrigerant when the system is inoperative and at ambient temperature with the vessel connected to the system. As shown in Fig. 1, a refrigerating system of the non-condensing type comprises a two-stage compressor 1, intercooler 3, cooler 4, heat exchangers 5 and 6 and a low temperature coil 7. The cooled compressed gas from exchanger 5 is expanded in turbine 8 then passes through heat exchanger 6 to a further expansion turbine 9 before passage to coil 7, the returning gas from the latter serving as the coolant in exchangers 5 and 6. A vessel 11 is connected to the compressor suction and discharge lines 14, 17 by valve-controlled lines 12, 15 so that refrigerant may be supplied to or withdrawn from the cycle to carry its cooling capacity. To prevent oil contamination the piston shafts pass through labyrinth seals 18, 19 having chambers 18a, 18b and 19a formed therein, chamber 18b being connected to a point intermediate the compression stage and chambers 18a, 19a to the suction line 15 via a line 20 containing a restriction 21 to return refrigerant to the system. A chamber 22 intermediate seals 18, 19 and the compressor crankcase is also connected to suction line 15 via line 23 containing an oil adsorber 24. The work produced by turbines 8 and 9 is dissipated by compressors 25, 26 disposed in braking circuits comprising throttles 29, 30 and heat exchangers 27, 28 and are driven by the turbines through shafts 31, 32. The latter are lubricated by gas obtained from the discharged sides of compressors 25, 26 the gas being returned through line 37 to pressure equalizing lines 33, 34 connecting the inlet sides of the compressors to the outlet sides of the turbines, lines 33, 34 containing regenerators 35, 36. In the system shown in Fig. 2 part of the cooled compressed gas from exchanger 5 is passed to heat exchanger 6 and then to an additional heat exchanger 49 in which at least part of the refrigerant condenses, the refrigerant then passing to an expansion valve 53 supplying a cooling coil 50. The remainder of the gas from exchanger 5 is expanded in an engine 40, the discharge from which rejoins the returning refrigerant at a point between exchangers 49 and 6 and aids in cooling exchangers 5 and 6. A labyrinth seal 42 having an annular chamber connected by a line 43 to the discharge side of the engine 40 is provided and a chamber intermediate seal 42 and the engine crankcase is connected to suction line 15 by line 44. The latter contains an oil adsorber 45 and a valve 46 controlled by a device 48 in response to the pressure difference between the annular and intermediate chambers. The refrigerant may be hydrogen, oxygen, nitrogen, helium or neon. |
