JPH0719635A - Pulse tube refrigerator - Google Patents

Abstract

PURPOSE:To further lower a produced low temperature by forming an end of a second pulse tube integrally with a cold heat generating heat exchanger in a state that the end of the tube is connected to the exchanger. CONSTITUTION:An end cooler 13 at an end of a second pulse tube 12 is formed integrally with a cold heat generating heat exchanger 7 in a state that the end of the tube 12 is connected to the exchanger 7. Thus, a thermal resistance on a heat exchanging route is reduced between flowing operation gas F in the exchanger and flowing operating gas G' at the end of the tube 12. That is, a heat dissipating temperature of the gas G' at the end of the tube 12 is set lower than that of the operating gas of the end of a pulse tube 8 by cooling the gas G' at the end of the tube 12. Thus, further lower temperature than that of the exchanger 7 is produced in a cold heat generating heat exchanger 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative heat exchanger, a cold heat generating heat exchanger, a pulse tube, and a tip cooler in a working gas path from a pulsating means for alternately repeating discharge and suction of a working gas. Related to the pulse tube refrigerator.

[0002]

2. Description of the Related Art Conventionally, in order to further reduce the generated low temperature in the above pulse tube refrigerator, as shown in FIG. 3, the discharge and suction of the working gas G from the pulsating means 1 are alternately repeated. In the working gas path F1, the (first) regenerative heat exchanger 6, the (first) cold heat generation heat exchanger 7, and the (first)
A branch operation for branching from between the first regenerative heat exchanger 6 and the first cold heat generating heat exchanger 7 to the basic configuration in which the pulse tube 8 and the (first) tip cooler 9 are connected in that order. By providing the gas path F2, the branch working gas path F2
The second regenerative heat exchanger 10, the second cold heat generating heat exchanger 11, the second pulse tube 12, and the second tip cooler 13 are connected in that order to the basic configuration side. The solid heat-conducting material X and the second cold heat generating heat exchanger 7 and the second cold heat generating heat exchanger 7 are exchanged so as to transfer heat between the first cold heat generating heat exchanger 7 and the second tip cooler 13 on the branch path side. Tip cooler 1
There is a cross over.

That is, by transmitting the low temperature generated in the first cold heat generating heat exchanger 7 which is the basic configuration side to the second tip cooler 13 via the solid heat conducting material X, the second pulse tube 12
Heat radiation temperature of the working gas G'at the tip of the
The cooling temperature of the working gas in the tip cooler 13 is set lower than the heat radiation temperature of the working gas in the tip portion of the first pulse tube 8 on the basic configuration side, whereby the second cold heat generation heat exchanger 1
In the first example, a lower temperature than that of the first cold heat generation heat exchanger 7 on the basic configuration side is generated.

[0004]

However, in the above-mentioned conventional configuration, in the heat transfer between the first cold heat generating heat exchanger 7 which is the basic configuration side and the second tip cooler 13 which is the branch path side. Since the solid heat-conducting material X has a large heat resistance, the efficiency of heat transfer (that is, the working gas G in the first cold heat generating heat exchanger 7 and the working gas G ′ in the tip portion of the second pulse tube 12 is Therefore, there is a problem that the desired lowering of the production low temperature is greatly limited.

In particular, since the pulse tube refrigerator is intended for extremely low temperatures of, for example, 150 K or 100 K or less, the above-mentioned thermal resistance of the solid heat conductive material X becomes a particularly large capacity deteriorating factor in low temperature generation. For this reason, the above problem becomes remarkable.

An object of the present invention is to make it possible to effectively achieve further lowering of the low temperature of formation by rational improvement.

[0007]

A first characteristic configuration of a pulse tube refrigerator according to the present invention is a regeneration heat exchanger and cold heat generation in a working gas path from a pulsating means for alternately repeating discharge and suction of a working gas. A branch working gas path that branches from between the regenerative heat exchanger and the cold heat generating heat exchanger is provided for the basic configuration in which the heat exchanger, the pulse tube, and the tip cooler are connected in that order, and this branch operation is performed. The second regenerative heat exchanger, the second cold heat generating heat exchanger, and the second pulse tube are connected in that order to the gas path, and the second tip cooler provided at the tip of the second pulse tube is the cold heat The tip portion of the second pulse tube is connected to the cold heat generation heat exchanger so that the flowing working gas in the generated heat exchanger and the circulating working gas in the tip portion of the second pulse tube are heat-exchanged. Form at some that have configured the integrally with cold generating heat exchanger.

A second characteristic configuration according to the present invention is the above-mentioned second configuration.
A second branch working gas path branched from between the regenerative heat exchanger and the second cold heat generating heat exchanger is provided, and a third regenerative heat exchanger and a third cold heat generating path are provided in the second branch working gas path. Connect the heat exchanger and the third pulse tube in that order,
The third tip cooler provided at the tip of the third pulse tube is configured to exchange heat between the working fluid flowing in the second cold heat generating heat exchanger and the working fluid flowing in the tip of the third pulse tube. The tip of the third pulse tube is connected to the second cold heat generating heat exchanger and is integrally configured with the second cold heat generating heat exchanger.

[0009]

In other words, in the above first characteristic configuration (see FIG.
Similarly to the conventional configuration shown in FIG. 3 described above, basically, the working fluid G flowing in the (first) cold heat generating heat exchanger 7 on the basic configuration side and the second pulse tube 12 on the branch path side are disposed. By heat exchange with the flow working gas G ′ at the tip, that is, the flow working gas G at the tip of the second pulse tube 12 is cooled by the flow working gas G in the (first) cold heat generation heat exchanger 7. By doing the second
The heat radiation temperature of the working gas G ′ at the tip of the pulse tube 12 (that is, the working gas cooling temperature in the second tip cooler 13) is set to the heat radiation of the working gas at the tip of the (first) pulse tube 8 on the basic configuration side. Lower than the temperature, which
The second cold heat generation heat exchanger 11 generates a lower temperature than that of the (first) cold heat generation heat exchanger 7 on the basic configuration side.

Then, as described above, the flow working gas G in the (first) cold heat generating heat exchanger 7 and the second pulse tube 1
In heat exchange with the flow working gas G ′ at the tip of the second pulse tube, as a heat exchange configuration, the tip of the second pulse tube 12 is connected to the (first) cold heat generation heat exchanger 7, Second tip cooler 13 at the tip of the pulse tube
Is integrally formed with the (first) cold heat generating heat exchanger 7, whereby the working gas G flowing in the (first) cold heat generating heat exchanger 7 and the working gas G ′ flowing in the tip portion of the second pulse tube 12 are formed. The thermal resistance on the heat exchange path between and is reduced.

In the second characteristic configuration (see FIG. 2), the flow working gas G'in the second cold heat generating heat exchanger 11 and the flow working gas G "in the tip portion of the third pulse tube 16 are heat-exchanged. In other words, by cooling the flow working gas G ″ at the tip of the third pulse tube 16 by the flow working gas G ′ in the second cold heat generating heat exchanger 11, the operation at the tip of the third pulse tube 16 is performed. Heat dissipation temperature of gas G "(that is, third tip cooler 17
Cooling temperature of the working gas in the second pulse tube 12 is lower than the heat radiation temperature of the working gas in the tip portion of the second pulse tube 12, so that it is lower in the third cold heat generating heat exchanger 15 than in the second cold heat generating heat exchanger 11. Generates low temperature.

Then, the third tip cooler 17 at the tip of the third pulse tube is connected to the second cold heat generating heat exchanger 11 so that the tip portion of the third pulse tube 16 is connected to the second cold heat generating heat exchanger 11. By being integrally configured, the thermal resistance on the heat exchange path between the flow working gas G ′ in the second cold heat generating heat exchanger 11 and the flow working gas G ″ at the tip of the third pulse tube 16 is reduced. Reduce.

[0013]

That is, according to the first characteristic configuration of the present invention, a solid heat conduction material is provided between the (first) cold heat generating heat exchanger on the basic configuration side and the second tip cooler on the branch path side. In comparison with the above-mentioned conventional configuration that applies the above, it is possible to reduce the thermal resistance in heat exchange between the working gas in those (first) cold heat generating heat exchangers and the working gas in the tip portion of the second pulse tube, It is possible to more effectively achieve the desired lowering of the production low temperature, and it is possible to efficiently obtain a lower low temperature.

Further, according to the second characteristic construction of the present invention, in addition to the fact that the second cold heat generating heat exchanger can obtain a lower temperature than that of the (first) cold heat generating heat exchanger of the basic construction side as described above. By obtaining a lower temperature lower than that of the second cold heat generating heat exchanger in the third cold heat generating heat exchanger, it is possible to more effectively achieve the intended lowering of the generated low temperature.

[0015]

EXAMPLES Next, examples will be described.

FIG. 1 shows a double pulse tube refrigerator,
1 is a compressor as pulsation means, and this compressor 1 is
A piston 3 that reciprocates by the driving rotation of the crankshaft 2.
Is housed in the compression chamber 4, and the reciprocating motion of the piston 3 alternately discharges the working gas G such as helium gas or hydrogen gas from the compression chamber 4 and sucks it into the compression chamber 4.

In the working gas path F1 from the compressor 1, a cooler 5, a first regenerative heat exchanger 6, a first cold heat generating heat exchanger 7, a first pulse tube 8 and a first tip cooler 9 are provided.
Are connected in that order, and in this basic configuration, the first cold heat generation heat exchanger 7 generates a low temperature of, for example, about 150K according to the refrigeration principle of the pulse tube refrigerator.

The cooler 5 has a function of pre-cooling the working gas G by exchanging heat between the working medium G and the cooling medium W1 using the atmosphere, cooling water, or other suitable fluid, and also the first regeneration. The heat exchanger 6 functions as a regenerator by having a heat storage element inside.

The first tip cooler 9 is operated at the tip of the first pulse tube 8 by exchanging heat between the working medium G2 and the cooling medium W2 using the atmosphere, cooling water, or other suitable fluid. Cool the gas G.

That is, according to the refrigeration principle of the pulse tube refrigerator, the adiabatic compression and adiabatic expansion of the working gas G precooled by the cooler 5 in accordance with the discharge and suction of the working gas G by the compressor 1 is performed by the first pulse tube 8 Alternately occur at
Along with this, the working gas G whose temperature has been raised by adiabatic compression is radiated in the first tip cooler 9, and the working gas G whose temperature has been lowered by adiabatic expansion is used to generate cold heat in the first cold heat generation heat exchanger 7. At the same time, the first regenerative heat exchanger 6 as a regenerator is made to store cold.

Then, the first for adiabatic compression as described above
With the repeated heat dissipation in the tip cooler 9 and the low temperature generation due to adiabatic expansion, the cold storage temperature in the first regenerative heat exchanger 6 and the cold temperature generated in the first cold heat generation heat exchanger 7 are gradually decreased. After the operation start-up mode, finally, in the steady operation, the first cold heat generation heat exchanger 7 is operated at the above-mentioned 150
Obtain a very low temperature such as K.

In contrast to the above basic structure, the double pulse tube refrigerator of this embodiment is provided with a branch working gas path F2 which branches from between the first regenerative heat exchanger 6 and the first cold heat generating heat exchanger 7, A second regenerative heat exchanger 10, a second cold heat generating heat exchanger 11, and a second pulse tube 12 are connected in this order to the branch working gas path F2.

A second tip cooler 13 is provided at the tip of the second pulse tube 12, and the second tip cooler 13 is a working gas flowing through the first cold heat generating heat exchanger 7 on the basic structure side. The first part of the second pulse tube 12 is connected to the first cold heat generating heat exchanger 7 so that the G and the working gas G ′ flowing at the tip part of the second pulse tube 12 are heat-exchanged. It is configured integrally with the cold heat generation heat exchanger 7.

Regarding the specific integrated structure of the first cold heat generating heat exchanger 7 and the second tip cooler 13, the first narrow channel a and the second narrow channel b are connected via the heat exchanging partition wall c. A heat exchanger N in which a large number of the first narrow channels a and the second narrow channels b are formed, and the first narrow channels a are circulated in the first cold heat generation heat exchanger 7. This heat exchanger N is used as a passage for the working gas G (that is, a passage for the working gas G to be circulated between the first regenerative heat exchanger 6 and the first pulse tube 8). 6 is provided in the working gas pipeline on the side of the basic configuration connecting the first pulse tube 8 and the other second fine flow path b is used as a passage for the working gas G ′ at the tip of the second pulse tube 12. As described above, the tip of the second pulse tube 12 is connected to the heat exchanger N. A form in which the end portions are connected is adopted, and the heat exchanger N constitutes the first cold heat generating heat exchanger 7 and the second tip cooler 13.

On the other hand, like the first regenerative heat exchanger 6, the second regenerative heat exchanger 10 functions as a regenerator having a heat storage element inside, and the second cold heat generating heat exchanger 11 is
As the cold heat extraction terminal of the double pulse tube refrigerator in this example, the cooling target medium W3 is cooled by the generated cold heat.

On the side of the branch working gas path F2, as in the case of the above-mentioned basic configuration side, basically, as the refrigeration principle of the pulse tube refrigerator, the discharge and suction of the working gas G by the compressor 1 The adiabatic compression and the adiabatic expansion are alternately generated in the two-pulse tube 12, the working gas G ′ whose temperature is raised by the adiabatic compression is radiated in the second tip cooler 13, and the working gas G whose temperature is lowered by the adiabatic expansion is generated. 'Causes the second cold heat generation heat exchanger 11 to generate cold heat and causes the second regenerative heat exchanger 10 as a regenerator to store cold.

Then, in the low temperature generation on the side of the branch path, as described above, the first tip cooler 13
When the circulating working gas G in the cold heat generating heat exchanger 7 and the circulating working gas G ′ in the tip portion of the second pulse tube 12 are heat-exchanged, that is, at the low temperature generated in the first cold heat generating heat exchanger 7, Pulse tube 1
The heat dissipation temperature of the working gas G ′ at the tip of the second pulse tube 12 (that is, the second tip cooler 1 is set by cooling the flowing working gas G ′ at the tip of the second pulse tube 12.
3) is lower than the working gas heat radiation temperature of the tip end of the first pulse tube 8 on the basic configuration side, whereby the second cold heat generation heat exchanger 1 on the branch path side.
In No. 1, a low temperature lower than that of the first cold heat generation heat exchanger 7 on the basic configuration side is generated.

Further, in exchanging heat between the flow working gas G in the first cold heat generating heat exchanger 7 and the flow working gas G'in the tip of the second pulse tube 12, the tip of the second pulse tube 12 is moved to the first position. By connecting the second tip cooler 13 integrally with the first cold heat generating heat exchanger 7 in the form of being connected to the first cold heat generating heat exchanger 7, the circulation working gas G in the first cold heat generating heat exchanger 7 is formed. And the circulating working gas G ′ at the tip of the second pulse tube 12 are caused to perform efficient heat transfer with reduced thermal resistance, whereby the second cold heat generation heat exchanger 11 on the branch path side is basically Efficiently generate a lower temperature that is lower than that of the first cold heat generation heat exchanger 7 on the configuration side (for example, while the low temperature generated in the first cold heat generation heat exchanger 7 is about 150 K, the second cold heat generation heat exchanger 7 Smell of exchanger 11 Efficiently generating a degree of cryogenic 70K).

[Other Embodiments] Next, other embodiments will be listed.

(1) As an improvement to the configuration of the embodiment shown in FIG. 1, as shown in FIG. 2, a second branch is provided between the second regenerative heat exchanger 10 and the second cold heat generating heat exchanger 11. A working gas passage F3 is provided, and a third regenerative heat exchanger 14, a third cold heat generating heat exchanger 15, and a third pulse tube 16 are connected in this order to the second branch working gas passage F3. The third tip cooler 17 provided at the tip of the third pulse tube 16 has a flow working gas G ′ in the second cold heat generating heat exchanger 11 and a flow working gas G ″ in the tip of the third pulse tube 16. The tip of the third pulse tube 16 to the second
It may be configured to be integrated with the second cold heat generating heat exchanger 11 in a form of being connected to the cold heat generating heat exchanger 11.

That is, the flow working gas G'in the second cold heat generating heat exchanger 11 and the flow working gas G "in the tip portion of the third pulse tube 16 are heat-exchanged, and the second cold heat generating heat exchanger 11 is heated. Generated cold heat causes the third pulse tube 16
The working gas G ″ at the tip of the third pulse tube 16 is cooled by cooling the working gas G ″ flowing through the tip of the third pulse tube 16.
(Ie, the working gas cooling temperature in the third tip cooler 17) is set lower than the working gas heat radiation temperature in the tip portion of the second pulse tube 12, whereby the third cold heat generation heat exchanger 15 Second cold heat generation heat exchanger 11
A triple pulse tube configuration that efficiently generates a lower temperature than the above is adopted.

(2) Similar to the improvement from the double pulse tube configuration shown in FIG. 1 to the triple pulse tube configuration shown in FIG. 2, a quadruple pulse tube configuration or a multiple pulse tube configuration more than that is adopted. May be.

(3) A specific integrated structure of the first cold heat generating heat exchanger 7 and the second tip cooler 13, and the cold heat generating heat exchanger 11 and the branch path side in the multiple pulse tube structure of triple or more. Various improvements can be made to the specific integrated configuration with the tip cooler 17.

(4) The working gas is not limited to helium gas or hydrogen gas, various kinds of gases can be applied, and the object to be cooled in the cold heat generating heat exchanger as the cold heat take-out terminal of the refrigerator does not matter.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a structural diagram showing an embodiment.

FIG. 2 is a structural diagram showing another embodiment.

FIG. 3 is a structural diagram showing a conventional example.

[Explanation of symbols]

 1 Pulsating Means 6 Regenerative Heat Exchanger 7 Cold Heat Generation Heat Exchanger 8 Pulse Tube 9 Tip Cooler 10 Second Regenerative Heat Exchanger 11 Second Cold Heat Generation Heat Exchanger 12 Second Pulse Tube 13 Second Tip Cooler 14 Third Regeneration heat exchanger 15 Third cold heat generation heat exchanger 16 Third pulse tube 17 Third tip cooler F1 Working gas path F2 Branch working gas path F3 Second branch working gas path G, G ', G "Working gas

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ichiro Fujishima 1-1-1, Hama, Amagasaki City, Hyogo Prefecture Kubota Technology Development Laboratory

Claims (2)

[Claims] 1. A working gas path (F1) from a pulsating means (1) which alternately repeats discharge and suction of a working gas (G).
A pulse tube refrigerator in which a regenerative heat exchanger (6), a cold heat generating heat exchanger (7), a pulse tube (8), and a tip cooler (9) are connected in that order. Vessel (6) and cold heat generating heat exchanger (7)
A branch working gas path (F2) branching from between and is provided, and in this branch working gas path (F2), a second regenerative heat exchanger (10), a second cold heat generating heat exchanger (11), and a second The second pulse tube (12) is connected in that order, and a second pulse tube (12) is provided at the tip of the second pulse tube (12).
The tip cooler (13) exchanges heat between the circulating working gas (G) in the cold heat generating heat exchanger (7) and the circulating working gas (G ′) in the tip portion of the second pulse tube (12). Further, a pulse tube refrigerator in which the tip of the second pulse tube (12) is connected to the cold heat generating heat exchanger (7) so as to be integrated with the cold heat generating heat exchanger (7). 2. A second branch working gas path (F3) is provided which branches from between the second regenerative heat exchanger (10) and the second cold heat generating heat exchanger (11). A third regenerative heat exchanger (14), a third cold heat generating heat exchanger (15), and a third pulse tube (16) are connected in this order to the branch working gas path (F3), and the third pulse tube Third provided at the tip of (16)
The tip cooler (17) includes the second cold heat generation heat exchanger (1
Circulating working gas (G ′) in 1) and circulating working gas (G ″) at the tip of the third pulse tube (16)
And the third pulse tube (1
The pulse tube refrigerator according to claim 1, wherein the tip of (6) is integrally formed with the second cold heat generating heat exchanger (11) in a form of being connected to the second cold heat generating heat exchanger (11). .