Improvements in or relating to thermodynamic reciprocating machines

摘要

1,139,885. Hot gas engines. PHILIPS' GLOEILAMPENFABRIEKEN N. V. Jan. 17, 1966 [Jan.20, 1965], No.2101/66. Heading F1S. [Also in Division F4] In a hot gas reciprocating machine the piston or piston like member 73, 74 which varies the volume of the expansion space 75, 76 and/or the cylinder wall co-operating therewith is provided with two seals separated by a space 89, 90 which has communication with a space in which a pressure variation occurs such that at any instant the pressure differential with respect to the pressure prevailing in the space on one side of the piston or piston like member is smaller than the pressure differential with respect to the pressure in the space on the other side of the piston or piston like member, the arrangement being such that the medium between the two seals has a temperature which is substantially equal to the temperature in that space in which pressure prevails which at any instant has the greater difference with respect to the pressure in the space between the seals. The invention is described as applied to cold gas refrigerators. The construction shown in the Fig. can also be readily applied to hot gas engines. The application to a V-cylinder and a multi-stage cold gas refrigerator is described. In one embodiment the space between the seals communicates with the expansion space through ducts in the displacer and through a regenerator mounted in or on the displacer and having a low resistance to flow. In another embodiment the displacer consists of two parts of different diameters and the refrigerator has two expansion spaces.