JPH0734296Y2 - Pulse tube refrigerator - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse tube refrigerator in which a regenerator and a pulse tube are connected to each other to generate cold heat in an endothermic portion by taking gas in and out of a compressor.

[0002]

2. Description of the Related Art A conventional pulse tube refrigerator (single inlet type pulse tube refrigerator) has a pulse tube refrigerator as shown in FIG.
The low temperature end (51) of the (50) and the low temperature end (53) of the regenerator (52) are communicated with each other through a heat absorption connecting pipe (54) serving as a cold head, and the refrigerant gas passage (from the compressor (55) ( The gas supplied to the high temperature end (57) of the regenerator (52) via the regenerator (52) and the endothermic connecting pipe (5)
It is introduced from the low temperature end (51) of the pulse tube (50) to the high temperature end (58) through the pulse tube (50), and the needle valve (59) and the buffer tank (58) are connected to the high temperature end (58) of the pulse tube (50). It had a configuration in which the phase shifter configured with 60) was placed.

A double-inlet type pulse tube refrigerator shown in FIG. 8 has also been proposed as a pulse tube refrigerator capable of achieving a lower temperature (the academic journal "Cryogenics", September 1990 issue). This double inlet type pulse tube refrigerator has a low temperature end (51) of the pulse tube (50) and a regenerator.
The low temperature end (53) of (52) communicates with each other through a heat absorption connecting pipe (54) serving as a cold head, and the compressor (55) and the refrigerant gas passage (5
The gas supplied to the high temperature end (57) of the regenerator (52) via 6) is transferred from the low temperature end (51) of the pulse pipe (50) via the regenerator (52) and the heat absorption connecting pipe (54). Introduced toward the high temperature end (58) side, pulse tube
At the hot end (58) of (50), the needle valve (59) and buffer tank (6
0) and the phase shifter composed of
A branch gas passage (61) branched from the refrigerant gas passage (56) is connected to a passage portion between the high temperature end of the tank and the buffer tank (60), and a needle valve (62) is connected to the branch gas passage (61). Place and
Water coolers (63, 64) are arranged at the high temperature ends of the regenerator (52) and the pulse tube (50) to cool the high temperature ends of the regenerator and the pulse tube with water.

[0004]

However, in the single-inlet type pulse tube refrigerator, since there is no moving part in the freezing generation part, a refrigerator with less vibration can be obtained. Since the solenoid valve (65) for switching gas supply and discharge to the pulse tube refrigerator was in rigid contact with the pulse tube refrigerator, the compressor unit and solenoid valve (65)
However, there remains a problem that it is not possible to prevent the vibration due to the switching of the transmission from being transmitted to the pulse tube refrigerator.

Further, a pulse tube refrigerator and a compressor unit,
Since the solenoid valve (65) is integrated, the whole size becomes large, and there is also a problem that the size is further increased especially in the case where the buffer tank is used. As a result, for example, it was difficult to use it for cooling a device such as an EDS detector of an electron microscope that dislikes slight vibration.

On the other hand, in the conventional double-inlet type pulse tube refrigerator, a large compressor similar to the single inlet type pulse tube refrigerator, and the high temperature end of the regenerator (52) and the pulse tube (50) are water-cooled. Due to the structure, there is a problem that the water cooler is directly connected to the refrigerator and the refrigerator becomes large. In addition, a needle valve (59) is placed between the pulse tube (50) and the buffer tank (60), and the pulse tube
Since the needle valve (62) is arranged in the branch gas passage (61) which connects the passage portion between the high temperature end of (50) and the buffer tank (60) and the refrigerant gas passage (56), Needle valve (5
9) There was also a problem that the gas flow was disturbed by (62) and a vortex flow was generated. The present invention aims to provide a double-inlet type pulse tube refrigerator that is compact and lightweight and has high cooling efficiency, focusing on such points.

[0007]

In order to achieve the above-mentioned object, the present invention is to connect an air-cooled type pulse tube radiator to the high temperature end of the pulse tube, and to connect the main passage to the pulse tube radiator. Form an inverted V-shaped passage in which the branch passage intersects in an acute angle, and the gas reservoir communicates with the end of the main passage forming an acute angle to the branch passage through an orifice and forms an obtuse angle with respect to the branch passage. The high temperature end of the pulse tube communicates with the end of the main passage, and the small diameter branch gas passage branched from the refrigerant gas passage communicating with the high temperature end of the regenerator is connected to the outer end of the inverted T-shaped passage. It is characterized in that it is connected to the section via a second orifice.

[0008]

In the present invention, an air-cooled type pulse tube radiator is connected to the high temperature end of the pulse tube, and an inverted inverted V-shaped passage in which the branch passage intersects the main passage at an acute angle is connected to the inside of the pulse pipe radiator. The gas reservoir is connected to the end of the main passage that forms an acute angle with the branch passage through an orifice, and
The high temperature end of the pulse tube communicates with the end of the main passage that forms an obtuse angle to the branch passage, and the narrow branch gas passage that branches out from the refrigerant gas passage that communicates with the high temperature end of the regenerator is inverted. Since it is connected to the outer end portion of the branch passage of the mold passage via the second orifice, the pulse tube radiator can be formed in a small size, and the portion between the pulse tube and the gas reservoir and the branch gas passage portion are oriented. Therefore, the gas flow is not disturbed.

[0009]

1 and 2 show an embodiment of the present invention.
2 is a schematic configuration diagram of a pulse tube refrigerator, FIG. 2 is a vertical sectional view of a cold heat generating portion, and FIG. 3 is a vertical sectional view of a main portion. This pulse tube refrigerator has a cold heat generating section (4) formed by connecting the pulse tube (1) and the regenerator (2) to each other at one end thereof via a heat absorption connecting path (3), and a compression unit. And a rotary valve unit (6) for switching and controlling the supply and discharge of high-pressure gas generated in the compressor unit (5) and the high-pressure gas to the cold heat generating section (4).

The compressor unit (5) includes a compressor (7) and a cooler.
(8), an oil separator (9), an oil adsorber (10) and a pressure-holding valve (11). The rotary valve unit (6) includes a rotary valve (1
2) and a valve drive motor (13). Then, the high pressure gas passage (14) derived from the adsorber (10) is connected to the primary side high pressure port of the rotary valve (12) by the flexible hose (15), and the primary side low pressure port of the rotary valve (12) is connected. The drawn out flexible hose (16) is communicatively connected to the compressor (7) through the low pressure gas return path (17).

The cold heat generating section (4) is composed of two stainless pipes.
(18) (19) are arranged in parallel, the lower end is fitted to the copper end cap (20), and the upper end is made of stainless steel mounting flange.
(21) Fitted and formed, one stainless steel pipe
The stainless mesh body (22) is laminated inside the (18), and the straightening vanes (23) are arranged at both upper and lower ends to form the regenerator (2), and the other stainless pipe (19).
A rectifying plate (24) is arranged at both upper and lower ends of the pulse tube to constitute the pulse tube (1). And, a gas distribution plate (25) and a spacer (26) are attached to the copper end cap (20) to form a heat absorbing communication passage (3), and a regenerator (2) and a pulse tube (1) are formed. To communicate.

An upper end portion of the regenerator (2) communicates with a gas introduction plug (27) attached to a mounting flange (21), and a refrigerant gas introduction pipe (28) continuously extended from the gas introduction plug (27). ) Communicates with the secondary port of the rotary valve (12) via a flexible hose (29). Then, the high pressure refrigerant gas generated in the compressor unit (5) by switching the rotary valve (12) is regenerator.
It is designed to be supplied to (2).

On the other hand, the upper end of the pulse tube (1) communicates with an air-cooled pulse tube radiator (30) mounted on the mounting flange (21). This pulse tube radiator (30) has a main passage (31)
An inverted gas passage (33) in which the branch passage (32) intersects at an acute angle is transparently provided, and the lower end of the main passage (31) communicates with the upper end of the pulse tube (1). , Flexible tube (34) made of a good conductor with one end sealed at the upper end of the main passage (31)
Are connected via an orifice plate (35). The flexible tube (34) constitutes a gas reservoir.

Further, the branch passage (32) has a pulse tube at its inner end side.
It is formed so as to face the upper end of (1), and a narrow branch gas passage (37) branched and led out from the refrigerant gas introduction pipe (28) is provided at the outer end thereof through the second orifice plate (38). Connected.

In the pulse tube refrigerator thus constructed,
Due to the pressure change of the high-pressure refrigerant gas flowing into the pulse tube (1) through the regenerator (2), a low temperature such as liquid nitrogen temperature (77K) is generated in the copper end cap (20). Moreover, in this case, the cold heat generating part (4) has no moving parts, and the rotary valve unit for controlling the supply / discharge of the refrigerant gas to / from the regenerator (2).
Flexible hose (15) (16) between (6) and cold heat generating part (4)
Since it is connected for communication with, it is possible to provide a vibration-free refrigerator.

Further, since the pulse tube (1) and the gas reservoir (34) and the branch gas passage (37) and the branch passage (32) are connected via an orifice, the gas flow is disturbed. In addition, since the branch passage (32) is connected to the main passage (31) at a sharp angle so as to converge on the pulse tube side, the gas flow from the branch passage (32) is ) Can be made to flow counter to the flowing gas, and the effect of the phase shifter can be enhanced.

FIG. 4 shows another embodiment of the cold heat generating part (4),
This is one stainless steel pipe that constitutes the regenerator (2).
Two pulse tubes (1) are arranged for (18). In this case, the gas introduction plug (39) is fitted to the upper end of each pulse tube (1), and the assembly passage (40) communicating with the upper end of each pulse tube (1) is passed through the mounting flange (21). The main passage where this collecting passage (40) is formed in the pulse tube radiator (30)
A gas reservoir (34) is connected to the main passage (31) through an orifice plate (35). Although not shown in the figure, the branch passage (32) intersects the main passage (31) at an acute angle, and the refrigerant gas communicating with the regenerator (2) in the branch passage (32). The small-diameter branch gas passage (37) branched from the introduction pipe (28) is connected through the second orifice plate (38).

In this case, the gas distribution plate 25 and the spacer 26 attached to the end cap 20 are formed as shown in FIGS. That is, the gas distribution plate (25) is shown in FIG.
As shown in, the regenerator-side gas insertion hole (41) formed in the bore corresponding to the inner diameter of the stainless steel pipe (18) of the regenerator (2) and the bore corresponding to the inner diameter of each pulse tube (1) were formed. Each pulse tube side gas insertion hole (42) is communicated with the communication passageway (43), and the spacer (26) has an outer diameter of the stainless pipe (18) of the regenerator (2) as shown in FIG. It has a regenerator side insertion hole (44) formed in a diameter corresponding to and a pulse tube insertion hole (45) formed in a diameter corresponding to the outer diameter of each pulse tube (1). In this embodiment, two pulse tubes (1) are arranged for one regenerator (2), but three pulse tubes (1) are arranged for one regenerator (2). You may make it arrange | position above.

In this way, when a plurality of pulse tubes (1) are arranged for one regenerator (2), the effective heat dissipation area of the pulse tubes (1) can be reduced, The cooling efficiency can be increased. Further, when the gas passages from each pulse tube (1) are gathered and the gas reservoir (34) is connected to the gathering passage (40) through the orifice plate (35), each pulse tube (1) The fluid wave can be made uniform.

[0020]

According to the present invention, since the air-cooling type pulse tube radiator is connected to the high temperature end of the pulse tube, the pulse tube radiator can be made compact and the refrigerator itself can be made compact. be able to.

Further, an inverted V-shaped passage is formed in the pulse tube radiator so that the branch passage intersects the main passage at an acute angle, and a gas reservoir is provided at the end of the main passage forming an acute angle with respect to the branch passage. The high-temperature end of the pulse tube communicates with the end of the main passage that forms an obtuse angle with the branch passage, and a small diameter branching out from the refrigerant gas passage that communicates with the high-temperature end of the regenerator. Since the branch gas passage is connected to the outer end portion of the branch passage of the inverted T-shaped passage through the second orifice, the refrigerant gas flowing from the branch passage side in the state of facing the gas flowing from the pulse tube to the gas reservoir. In addition to being able to flow, the phase shift effect can be enhanced, and since the portion between the pulse tube and the gas reservoir and the branch gas passage portion are made of orifice, they can cause turbulence in the gas flow. It is eliminated.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a pulse tube refrigerator.

FIG. 2 is a vertical cross-sectional view of a cold heat generating portion.

FIG. 3 is an enlarged vertical sectional view of a main part.

FIG. 4 is a vertical cross-sectional view of a cold heat generating portion of another embodiment.

FIG. 5 is a perspective view of a gas distribution plate used in another embodiment.

FIG. 6 is a perspective view of a spacer used in another embodiment.

FIG. 7 is a schematic configuration diagram of a conventional single-inlet type pulse tube refrigerator.

FIG. 8 is a schematic configuration diagram of a conventional double-inlet type pulse tube refrigerator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pulse tube, 2 ... Regenerator, 3 ... Connection path for heat absorption, 7 ... Compressor, 28 ... Refrigerant gas passage, 30 ... Pulse tube radiator, 31 ...
Main passage, 32 ... Branch road, 33
… Inverted passage, 34… Gas reservoir, 35… Olyphus, 37…
Branch gas passage, 38 ... 2nd orifice.

Claims (2)

[Scope of utility model registration request] 1. A compressor (7) comprising a low temperature end of a pulse tube (1) and a low temperature end of a regenerator (2) which are communicated with each other through a heat absorption connecting path (3).
From the low temperature end of the pulse tube (1) to the high temperature end of the regenerator (2) via the refrigerant gas passage (28) through the regenerator (2) and the heat absorption connecting path (3). In a pulse tube refrigerator configured to be introduced toward the high temperature end side, an air-cooled type pulse tube radiator (30) is connected to the high temperature end of the pulse tube (1), and inside this pulse tube radiator (30) In addition, the branch passage (32) intersects the main passage (31) at an acute angle,
3) forming the main passage with an acute angle to the branch passage (32)
The gas reservoir (34) communicates with the end of (31) through the orifice (35), and the high temperature of the pulse tube (1) is provided at the end of the main passage (31) forming an obtuse angle with the branch passage (32). Connect the ends,
A narrow branch gas passage (37) branched from the refrigerant gas passage (28) communicating with the high temperature end of the regenerator (2) is provided with an outer end of the branch passage (32) of the inverted V-shaped passage (33). A pulse tube refrigerator characterized in that it is connected to the section via a second orifice (38). 2. A plurality of pulse tubes (1) for the regenerator (2)
2. The pulse tube refrigerator according to claim 1, wherein the low temperature end of each pulse tube (1) and the low temperature end of the regenerator (2) are communicated with each other by a heat absorption connecting path (3).