GB1050270A - - Google Patents

Abstract

1,050,270. Refrigerating. ARTHUR D. LITTLE Inc. Dec. 23, 1963 [Nov. 12, 1963], No. 50688/63. Heading F4H. In a refrigerating system of the type described in Specification 938,182 a piston is rigidly connected to the displacer and movement of the piston and displacer is controlled by admitting fluid to and withdrawing fluid from an enclosed space on one side of the piston. As shown a combined piston-displacer unit 13 is reciprocable in a housing 10, the piston part of the unit moving in an upper housing portion 12 to define a driving space 16 of variable volume and the displacer part moving in a lower housing portion 11 to define spaces 14 and 15 of variable volume. High and low pressure vessels 18 and 20, connected by a compressor 23, are provided and at the beginning of the cycle (Fig. 1(A)) a valve 38 is opened to admit highpressure fluid to space 16 to move unit 13 downwardly to the position shown in Fig. 1(B). A valve 26 is then opened to admit high-pressure fluid through line 27 to space 14 to compress residual fluid therein, valve 38 remaining open to maintain unit 13 in its Fig. 1(B) position. Valve 38 is then closed and a valve 39 opened to communicate space 16 with low-pressure vessel 20 so that unit 13 moves upwardly and heated compressed fluid is displaced from space 14 and, together with high-pressure fluid from valve 26, passes through a regenerator 34, where it is cooled, to space 15. A valve 30 is then opened and the fluid in space 15 expands and returns to vessel 20, delivering refrigeration to a load 37 and being heated in regenerator 34 to a temperature higher than that at which the high-pressure fluid enters space 14. In other embodiments separate high- and lowpressure fluid sources are provided for the driving and refrigeration cycles (Figs. 6 to 9, not shown), line 27 is omitted and spaces 14 and 15 are interconnected by a line 46 containing a further regenerator 47 (Figs. 6 and 8A) and the piston and displacer (which may be of stepped form) are formed separately and connected by a shaft 50 (Figs. 7 to 9). In the embodiment of Fig. 8 a seal 51 is provided between piston 49 and displacer 48, the space beneath the piston and above the seal being used as the driving space 16 and the space 14a above the piston being used as an auxiliary to space 14. A constructional form of the apparatus is illustrated in Figs. 10 and 11 (not shown).