Pulse tube refrigerator

Abstract

A pulse tube refrigerator that is small in size and free from vibration and electric noise. A pulse tube refrigerator (1) has a pulse tube, a cool storage unit connected to the low-temperature side of the pulse tube, a vibration generator connected to the high-temperature side of the cool storage unit, and a reservoir with an orifice, connected to the high-temperature side of the pulse tube. The vibration generator is a thermally driven pressure wave generator having thermal drive tubes (heat exchangers (4-4a) for heat radiation), a phase shifter (7), and a return path (6). Sufficiently heating a heat exchanger (3) for heating causes self-exciting vibration to be generated in a work transmission tube (5), and work is returned to the thermal drive tubes through the phase shifter (7) and the return path (6) arranged on the work output side of the work transmission tube (5). The work is amplified by the thermal drive tubes, and is then outputted from the work transmission tube (5) and fed to the pulse tube refrigerator (1). A vibration generator for a pulse tube refrigerator that is small in size and free from vibration and noise can be realized.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a pulse-tube refrigerator, especially to the pulse-tube refrigerator equipped with a pressure-vibration generator that generates pressure vibration by heat. BACKGROUND OF THE INVENTION [0002] A pulse-tube refrigerator consists of a pulse tube, a cool storage unit connected to the low-temperature side of the pulse tube, and a compressor connected to the high-temperature side of the cool storage unit. The pulse-tube refrigerator dispenses with moving parts at the low-temperature side. A pulse-tube refrigerator with a motor-driven compressor generates pressure vibration in the pulse tube by switching open and close alternately a pair of high-pressure and low-pressure valves that are settled between the compressor and the cool storage unit. The basic-type pulse-tube refrigerator by Gifford utilizes a surface heat-pumping effect. An orifice-type pulse-tube refrigerator has a buffer (reservoir tank) connected through the orifi...

AI Technical Summary

Benefits of technology

[0012] In order to solve the above mentioned problems, the present invention has configuration of a pulse-tube refrigerator comprising a pulse tube, a cool storage unit connected to the low-temperature side of the pulse tube, a vibration generator connected to the high-temperature side of the cool storage unit, and a reservoir with an orifice connected to the high-temperature side of the pulse tube, and said vibration generator consists of a heat-driven tube equipped with a heat-storage unit, a heating heat exchanger, a radiation heat exchanger, and a work transmission tube, of a phase shifter connected to an outlet portion of the heat-driven tube, and of a heat-driven pressure-wave generator equipped with a return path to connect the other portion of the phase shifter and the inlet end of the heat-driven tube. The configuration of the present invention enabled to implement a compact pulse-tube refrigerator free from vibration and noise. In other words, applying a solid displacer for the resonator and the phase shifter of the vibration generator and disposing them in facing opposite made the device compact and reduced vibration. The heat-driven pressure-wave generator with a resonator tube by the former arts was inevitably large since a small-size resonator does not resonate. A rather small-size resonator tube of former arts presented very low efficiency from the friction between the operation gas and the surface of the tube and was not suitable for actual use. By using a resonator and a phase shifter of the solid displacer, a compact and efficient heat-driven pressure-wave generator can be implemented. From the similar reason, arranging a resonator and a phase shifter of the solid displacer at the heat-absorber side enables to implement a compact and efficient pulse-tube refrigerator.

Problems solved by technology

The heat-driven pressure-wave generator with a resonator tube by the former arts was inevitably large since a small-size resonator does not resonate.

A rather small-size resonator tube of former arts presented very low efficiency from the friction between the operation gas and the surface of the tube and was not suitable for actual use.

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