Aisin Seiki Kabushiki Kaisha

Ecti Kabushiki Kaisha

Takayuki Matsui

Tatsuo Inoue

Yoshihiro Ishizaki

A pulse tube refrigerator according to the present invention is capable of performing cryogenic operation sufficiently. The cryostat includes regenerators and pulse tubes. Each regenerator has a cold stage at an upper end thereof. Each pulse tube has a low-temperature end portion at a lower end thereof and a high-temperature end portion thereof, the low-temperature end portion being located lower than the cold stage. The cold stage and the low-temperature end portion are connected to each other through a line whose cubic volume is substantially negligible in comparison with that of the pulse tube. Since the pulse tube has working gas of relatively high density in an upper portion thereof and working gas of relatively low density in a lower portion thereof, there is no convection of working gas induced by the gravity. Thus, the cryostat performs cryogenic operation sufficiently without being adversely affected.

Pulse tube refrigerator

A multistage type tube refrigerator comprising a regenerator-side pressure oscillation generator, first regenerator connected to the regenerator-side pressure oscillation generator, first cold head connected to the low temperature side of the first regenerator, a first pulse tube having one end connected to the first cold head and the other end connected by way of a first flow regulating mechanism to a first pulse tube-side phase shifter, second regenerator having one end connected to the first cold head and the other end connected to the second cold head, a second pulse having one end connected to the second cold head and the other end connected to second pulse tube-side phase shifter by way of second flow regulating mechanism, in which the first pulse tube-side phase shifter and the second pulse tube-side phase shifter are controlled independently of each other. Further, the pulse tube refrigerator operated while setting the phase angle of the pulse tube-side phase shifter to -50.degree. to -120.degree. relative to the regenerator-side pressure oscillation generator, while setting the phase angle of the second pulse tube-side phase shifter 15.degree. to -90.degree..

Multistage type pulse tube refrigerator

A pulse tube refrigerator includes a compression space defined by a compression piston inside a cylinder, an expansion space defined by an expansion piston inside a cylinder, the expansion piston being reciprocated at an advance angle of a constant phase difference within a range of 10.degree.-45.degree. relative to the compression piston, and first and second thermal systems communicating the compression and expansion spaces. Each thermal system has a radiator, a regenerator, a cold head and a pulse tube, with the regenerator of the second thermal system being composed of two regenerator sections. The cold head of the first thermal system is made to perform a heat exchange with the second thermal system between the two regenerator sections thereof, whereby a very low temperature is obtained from the cold head of the second thermal system.

Pulse tube heat engine

A pulse tube refrigerating system comprising a compressing cavity for compressing a working fluid, a heat radiator connected with the compressing cavity and a regenerator connected with the heat radiator. A pulse tube is provided and connected with the heat radiator through a refrigerating section. The pulse tube is connected through a heat exchanger and a flow regulating valve with an expansion cavity which is operable with a phase difference with respect to the compressing cavity, whereby the working fluid from the compressing cavity is cooled by the heat radiator and passed through the refrigerating section into the pulse tube, the working fluid in the pulse tube being compressed by the working fluid from the refrigerating section to be increased in temperature and passed to the heat exchanger to radiate heat.

Growing community of inventors

Fujisawa, Japan

Takayuki Matsui