SU974063A1 - Gas cryogenic machine - Google Patents

Description

The invention relates to refrigeration engineering, in particular to gas cryogenic machines.

A known gas cryogenic machine operating in the Stirling cycle, containing two cylinders with a compressor and a datander piston, sealing diaphragms and a communication line for the working volume of cylinders with a crankcase cavity 1.

A disadvantage of the known gas cryogenic machine is the lack of accurate reliability, since the diaphragm is. we, installed on working pistons, require the creation of a constant pressure differential, and also wear out quickly.

The purpose of the invention is to increase the reliability and service life of the machine.

The goal is achieved by the fact that a second piston is installed in each cylinder, forming an auxiliary cavity with the first and provided with sealing diaphragms, and an additional throttle and bellows are installed on the communication line of the working volume of cylinders by means of the crankcase.

The drawing shows a constructive implementation of a gas cryogenic machine.

Claims (2)

The gas pumping machine contains cylinders 1 and 2, in which the compressor and expander nopujHH 3 and 4, respectively, are installed, rigidly connected through connecting rods 5 and 6 to the crankshaft 7 located in the crankcase 8 of the machine. Pistons 3 and 4 have seals 9 and 10. In cylinders and 2, second pistons 11 and 12 are installed, equipped with sealing diaphragms 13 and 14 and forming auxiliary cavities 15 and 16 with pistons 3 and 4. Mai-iHHa is equipped with line 17 zi working volume of cylinders the compression cavity 18 and the expansion cavity 19 with the crankcase cavity 8. On the communication line 17, a throttle 20 and a bellows 21 are installed, the inner cavity 22 of the bellows 21 communicating with the crankcase cavity 8. In the second piston 12 installed in the expansion cylinder 2, there is an insulating cap 23 forming a gap 24 with the walls of the cylinder 2. The compression cavity 18 and the expansion cavity 19 communicate with each other through the cooler 25, the regenerator 26 and the load heat exchanger 27. Gas cryoge 1 on the machine work as follows. The compressor and expander pistons 3 and 4 are driven in reciprocating motion by connecting rods 5 and b and crankshaft 7 with the phase shift necessary to implement the Stirling cycle. The movement of the compressor and expander pistons 3 and 4 through the gas auxiliary cavities 15 and 16 transmits the movement of the second pistons 11 and 12, and the pressure in the auxiliary cavities 15 and 16, in the cavity 18 Compress and in the expansion cavity 19 is almost the same every time Since the elastic forces of the sealing diaphragms 13 and 14, the inertia and friction forces of the second pistons 11 and 12 are small compared to the gas forces. Therefore, in the working and auxiliary cavities, the law of pressure change corresponds to that required for the Stirling cycle. When the compressor piston 3 moves upwards, the volume of the cavity 18 is compressed and the working gas is compressed in the refrigerator 25, the regenerator 26, the heat exchanger 27 on the load and the expansion cavity 19. Further, when the compressor piston n 3 moves upwards, and the expander piston 4 downward, the working gas is pushed through the regenerator 26 into the expansion cavity 19. Then, with the further movement of the expander piston 4 downwards, the expansion in the expansion cavity 19 occurs with the production of useful cold. Then, when the expander piston 4 moves upwards and the compressor piston 3 moves downwards, the gas is pushed back into the compression cavity 18. Then the cycle repeats. When the pressure in the cycle increases due to the compression of gas in the auxiliary cavities 15 and 16, the constrictions 3 and 4 converge with the second pistons II and 12 to the minimum distance between them, and as the pressure decreases, the gaps increase. Since in the Stirling cycle the ratio of the maximum and minimum pressures is approximately equal to two, the volume of the auxiliary cavities is small compared to the working cavities and not. causes large losses. The sealing diaphragms hermetically separate the working cavity from the crankcase cavity. To equalize the average pressures at multiple starts and stops of the machine and to ensure the necessary position of the second pistons 11 and 12 in cylinders 1 and 2, the working cavity is connected to the crankcase 8 through throttle 20 and bellows 21. Using this technical solution ensures reliable operation of the seals and most increase the life of the entire machine as a whole. Claim 1. A gas cryogenic machine operating in the Stirling cycle, containing two cylinders with a compressor and expander pistons, sealing diaphragms and a working volume of cylinders with a crankcase cavity, in order to increase reliability and A second piston is installed in each cylinder, which forms an auxiliary cavity with the first one and is equipped with sealing diaphragms. 2. Machine pop. l, in contrast to the fact that, in order to ensure the equalization of pressures during start and stop, the throttle and bellows are additionally installed on the communication line of the working volume of the cylinders with the crankcase, and the latter is connected to the crankcase. Sources of information taken into account in the examination 1. USSR author's certificate in application 3232004, cl. F 25 B 9/00, 01/06/81. g /