JPH09273823A - Refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the dead volume of working gas, improve heat radiation efficiency and reduce the overall size of an apparatus. SOLUTION: The upper part of a compression cylinder 3 is a non-action space and the base end of an expansion cylinder 2 and the base end of the compression cylinder 3 communicate with each other via a connecting gas path 18 embedded in an apparatus main body. Expansion side partition members 20 having an outside diameter smaller than the inside diameter of a lower part 2a of the expansion cylinder 2 are arranged around a displacer rod 21 with a narrow gap kept between the lower part 2a and the partition members 20 to form an expansion side narrow, tubular gas path 22. Similarly, compression side partition members 30 having an outside diameter smaller than the inside diameter of a lower part 3a of the compression cylinder 3 are arranged around a piston rod 31 with a narrow gap kept between the lower part 3a and the partition members 30 to form a compression side tubular, narrow gas path 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating apparatus using a gas compression expander such as a Stirling cycle engine and a Brummier cycle engine.

[0002]

2. Description of the Related Art In recent years, there has been an urgent need to develop techniques for preserving various samples and various materials at extremely low temperatures in advanced technology fields such as the field of biotechnology and the field of electronic devices. In particular, Stirling refrigerating devices and the like have been attracting attention as means for achieving the above-mentioned extremely low temperatures, and are being widely used for various infrared sensors, freezers for cooling superconducting devices and the like, biomedical freezers, freezers and the like.

Here, the operation principle of the structure of the displacer type Stirling refrigerating apparatus will be described with reference to FIG. In the main body housing 1, an expansion cylinder 2 arranged inside the expander main body container and a compression cylinder 3 arranged inside the compressor main body container are attached with an angle difference of 90 degrees, and are built in the expansion cylinder 2. Displacer 6
Then, the compression piston 7 built in the compression cylinder 3 is connected to the common crank mechanism 5 and is reciprocally driven in a state where the phases are 90 degrees out of phase with each other.

The displacer 6 is filled with a regenerator material 14 made of, for example, a sintered metal, and the working gas flowing from one opening of the displacer 6 is regenerator material 14.
In the process of passing through the inside of the
Heat exchange with the cold storage material 14 is performed.

This displacer 6 also has a function as a regenerative heat exchanger, and its heat exchange performance greatly influences the coefficient of performance of the refrigeration system. The expansion cylinder 2 and the compression cylinder 3 are separated from the crank chamber 12 by oil seals 8 and 9, respectively, and the base end portion of the expansion cylinder 2 and the compression space portion of the compression cylinder 3 communicate with each other through a gas passage 4. Has been done. As a result, the compression space 13 formed in the compression cylinder 3 and the expansion space 11 formed in the expansion cylinder 2 become
Through the gas passage 4. On the other hand, the oil 10 is injected into the crank chamber 12.

Next, the operation of the Stirling refrigerating apparatus having the above-mentioned structure will be described with reference to FIG.
In FIG. 4, the horizontal axis represents time T and the vertical axis represents stroke S.

In the Stirling refrigerator, the displacer 6 reciprocates as shown by curves B and C in FIG. 4 and at the same time the compression piston 7 reciprocates as shown by curve D in FIG. Is shown in FIG.
The volume changes in the width region between the straight line A and the curve B, and the volume of the compression space 13 of the compression cylinder 3 changes in the width region between the curves C and D in FIG.

As a result, in the process of FIG. 4, the gas in the compression space 13 is compressed and flows into the expansion cylinder 2 through the gas passage 4 (ideally isothermal compression). In the process of FIG. 4, this gas passes through the regenerator material 14 in the displacer 6 and exchanges heat with the regenerator material 14 to lower the temperature (cooling with constant volume). The gas that has passed through the cold storage material 14 flows into the expansion space 11 of the expansion cylinder 2 in the process of FIG. 4, and then expands as the compression piston 7 descends (ideally, isothermal expansion). Next, in the process of FIG. 4, as the displacer 6 rises, the gas in the expansion space 11 passes through the regenerator material 14, exchanges heat with the regenerator material 14, and after the temperature rises, the gas passage 4 And then introduced again into the compression space 13 (heating at constant volume).

As a result, the cold head 15 provided on the head of the expansion cylinder 2 is cooled.

[0010]

In order to increase the compression ratio and improve the refrigerating capacity of the device, the volume (dead volume) inside the device through which the working gas flows is designed to be as small as possible.

However, since the working gas has a high temperature in the compression space 13, it is necessary to sufficiently radiate the high temperature working gas in the dead volume portion such as the gas passage 4 and then supply it to the displacer 6 side. There is a fear that the dead volume becomes large due to the improvement of the capacity and the whole apparatus becomes large.

The present invention has been made in view of the above circumstances, and provides a refrigerating apparatus in which the dead volume of the working gas is reduced, the heat radiation efficiency is improved, and the size of the entire apparatus is reduced. Is.

[0013]

The present invention is a refrigerating apparatus in which the base end side of a compression cylinder is a compression space and the compression space and the base end side of an expansion cylinder are connected by a gas passage.

By using this structure, the gas passage can be shortened, and the dead volume can be reduced and the device structure can be simplified. And specifically, it comprises a displacer for reciprocally driving the inside of the expansion cylinder, and an expansion side heat exchange means for exchanging heat with the working gas introduced into the displacer from the compression space, the expansion side heat exchange means comprising: The expansion side partition member is disposed in the vicinity of the lower part of the expansion cylinder, and the expansion side gas passage having a narrow cylindrical gap is formed between the lower part and the expansion side partition member. Through which the working gas passes, the high temperature generated in the compression space is extracted to the outside.

Alternatively, the compression space and the expansion space are connected by a gas passage through a regenerative heat exchanger arranged on the outer peripheral surface of the expansion cylinder, and an expansion piston that reciprocally drives the inside of the expansion cylinder. An expansion side heat exchange means for exchanging heat with the working gas introduced into the regenerative heat exchanger from the compression space, the expansion side heat exchange means being an expansion provided on an outer peripheral surface of a lower portion of the expansion cylinder. A side partition member, and an expansion side gas passage having a narrow cylindrical gap formed between the expansion side partition member and the expander main body container, wherein the working gas passes through the expansion side gas passage. The high temperature generated in the compression space is taken out.

By using any one of these configurations,
The gas passage has a large heat exchange area, and the working gas that has been compressed on the compressor side and has a high temperature is efficiently radiated by passing through this gas passage, and the gas passage is formed in a narrow gap. The volume of the passage is reduced, the dead volume is reduced, and the ratio of the working gas introduced into the expansion space to the total enclosed amount is increased to obtain a large compression ratio.

Further, preferably, there is provided compression side heat exchange means for exchanging heat with the working gas introduced into the displacer from the compression space, and the compression side heat exchange means is disposed in the vicinity of a lower portion of the compression cylinder. A compression-side partition member and a compression-side gas passage having a narrow cylindrical gap formed between the lower portion and the compression-side partition member are provided, and the working gas passes through the compression-side gas passage so that the compression is performed. The high temperature generated in the space is taken out to the outside.

Alternatively, there is provided a compression side heat exchange means for exchanging heat with the working gas introduced into the regeneration heat exchanger from the compression space, and the compression side heat exchange means is disposed in the vicinity of a lower portion of the compression cylinder. A compression-side partition member, and a compression-side gas passage having a narrow cylindrical gap formed between the lower portion and the compression-side partition member. The high temperature generated in the compression space is taken out.

By using any one of these structures, it is possible to further improve the heat radiation ability to take out the high temperature generated in the compression space to the outside.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a refrigerating apparatus of the present invention will be described below with reference to the drawings. The same configurations as those of the above-described conventional example are designated by the same reference numerals,
Detailed description of these parts will be omitted.

FIG. 1 shows an example of a Stirling refrigerating apparatus to which the present invention is applied. The refrigerating apparatus shown in this example has an expander 16 for generating refrigerating heat, like the conventional apparatus described above. A compressor 17 that receives the working gas expanded in the expander 16 and returns the compressed working gas, and these expanders 1
6 and a crank chamber 12 as a drive chamber for operating the compressor 17.

The expansion cylinder 2 and the compression cylinder 3 are separated from the crank chamber 12 by oil seals 8 and 9, respectively, and the upper portion of the compression cylinder 3 serves as a non-operating space, and the base end portion of the expansion cylinder 2 and the compression cylinder 3 are separated. The base end portions of the two are communicated with each other by a communication gas passage 18 embedded in the apparatus body. As a result, the compression cylinder 3
Compression space 19 and expansion cylinder 2 formed on the base end side of the
The expansion space 11 formed in the above is communicated with the gas passage through the regenerator material 14. As a result, the gas passage can be shortened, the dead volume can be reduced, and the device structure can be simplified.

Further, the lower portion 2a of the expansion cylinder 2 is
An expansion side partitioning member 20 having an outer diameter slightly larger than the inner diameter of the upper portion 2b of the expansion cylinder 2 with which the displacer 6 is in sliding contact and having an outer diameter slightly smaller than the inner diameter of the lower portion 2a is arranged around the displacer rod 21. At the same time, the expansion-side gas passage 22 having a narrow gap is formed near the lower portion 2a. A disk-shaped heat radiation fin 23 is disposed on the outer peripheral surface of the expander 16 in the lower portion 2a of the expansion cylinder 2, whereby the expansion side heat exchange means 2 is provided.
4. In the description of the present embodiment, the lower portion 2a of the expansion cylinder 2 of the expansion side heat exchange means 24 is referred to as
Although the waist is expanded more than the inner diameter of the upper portion 2b of the expansion cylinder 2, the same inner diameter may be used in order to simplify and downsize the device structure. However, in this case, the heat exchange area of the gas passage becomes small, so that the heat exchange amount slightly decreases.

Similarly, in the lower portion 3a of the compression cylinder 3, a cylindrical compression-side gas passage 3 having a narrow gap, which is closely disposed.
2, a compression side partition member 30 having an outer diameter slightly smaller than the inner diameter of the lower portion 3a is arranged around the piston rod 31. A disk-shaped heat radiation fin 33 is arranged on the outer peripheral surface of the compressor 17 in the lower portion 3a of the compression cylinder 3, and thereby the compression side heat exchange means 34 is configured.

Therefore, by providing the expansion side heat exchange means 24 and the compression side heat exchange means 34, the dead volume can be reduced and the heat radiation surface can be enlarged, and the working gas heated in the compression space 19 can be radiated by both heat radiation means. After sufficiently dissipating heat in 24 and 34, the heat is supplied to the displacer 6. As a result, the temperature rise on the base end side of the displacer 6 is suppressed and the temperature can be kept low as compared with the conventional case. Therefore, the temperature at the top dead center side of the displacer 6 is further lowered, and the temperature of the cold head 15 can be lowered.

Here, the case where the expansion side heat exchange means 24 and the compression side heat exchange means 34 are provided in the expansion cylinder 2 and the compression cylinder 3, respectively, has been described, but at least the expansion side heat exchange means is required to obtain the above-mentioned effect. It is necessary to provide means 24. However, in this case, although the heat radiation capacity is slightly inferior to the case where the expansion side heat exchange means 24 and the compression side heat exchange means 34 are provided, the overall size of the device can be further reduced.

With the above construction, when the crank mechanism 5 is rotationally driven in the counterclockwise direction as in the case of FIG. 3, the compression piston 7 in the compression cylinder 3 of the compressor 19 moves to the base end side. As a result, the working gas such as helium that is difficult to liquefy and fills the compression space 19 is compressed. Then, the compressed working gas, the compression side gas passage 32 of the compression side heat exchange means 34 acting as a radiator, the communication gas passage 18 embedded in the apparatus body, and the expansion side heat exchange acting as a radiator. By passing through the expansion side gas passage 22 of the means 24,
After the heat generated during compression is radiated to the outside and cooled to near room temperature, the cool storage material 14 is discharged from the opening 6a of the displacer 6.
Flows into.

The working gas flowing into the regenerator material 14 is cooled as the displacer 6 descends and flows into the expansion space 11 from the opening 6a of the displacer 6.
At this time, the expansion space 11 is filled with the compressed working gas and is in a high pressure state.

Thereafter, as the piston 7 rises, the expansion space 11 is expanded, the inflowing high-pressure working gas is rapidly expanded, and the pressure sharply drops, so that the working gas becomes low in temperature.

When the displacer 6 starts to rise, the low-temperature working gas is returned from the displacer 6 to the compression space 19 through the gas passages 22, 18, 32. At this time, the regenerator material 14 in the displacer 6 passes. It is cooled by the working gas to a low temperature, and the regenerator material 14 has a predetermined thermal gradient.

By the way, as described above, the working gas flows back and forth between the compression space and the expansion space through the compression-side gas passages 32 and 22 each having a narrow cylindrical gap. The compression side gas passages 32, 22 have a large heat exchange area, and the working gas compressed on the compressor side and having a high temperature has a high heat exchange area.
Heat is efficiently dissipated by passing through. Further, since the gas passages 32 and 22 are formed in a narrow gap, the volume of the gas passages is reduced, the dead volume is reduced, the ratio of the working gas introduced into the expansion space to the total enclosed amount is increased, and a large compression is achieved. The ratio can be obtained. As a result, the working gas can be cooled to a lower temperature during expansion.

As described above, the process in which the working gas compressed in the compression space is supplied to the expansion space and expanded, and the expanded gas returns to the compression space 19 again completes one thermal cycle. The process is repeated by the rotational movement of the crank mechanism 5. As a result, the temperature of the working gas and the temperature of the regenerator material 14 in the expansion space 11 gradually decrease,
Since the cold head 15 has the lowest temperature, this refrigeration heat can be taken out from the heat exchanger (not shown) to the refrigeration temperature (not shown).

Next, FIG. 2 shows another embodiment of the present invention. In the figure, the same components as those shown in FIG. Detailed description is omitted. In the Stirling refrigerating apparatus shown in this example, the main difference from FIG. 1 is that the expander side is configured by using an expansion piston 41 instead of the displacer 6, and a two piston type is used.

In place of the cool storage material 14 in the displacer 6 of FIG. 1, a regenerative heat exchanger 43 made of a doughnut-shaped cool storage material 44 is arranged on the outer peripheral surface of the expansion cylinder 42, and the entire expander body container is provided. It is covered with 45.

An expansion side partition member 40 having an outer diameter slightly smaller than the inner diameter of the expander main body container 45 is arranged on the outer peripheral surface of the lower portion 42a of the expansion cylinder 42, and is arranged close to the expander main body container 45 to form a gap. Narrow gas passage 4 on the expansion side
6 are formed. Then, a disk-shaped fin 47 is arranged on the outer peripheral surface of the lower part of the expander main body container 45, whereby the expansion side heat exchange means 48 is constituted.

As a result, the compressed working gas, the compression side gas passage 32 of the compression side heat exchange means 34 acting as a radiator, the communication gas passage 18 embedded in the apparatus main body,
After passing through the expansion-side gas passage 46 of the expansion-side heat exchange means 48 acting as a radiator, the heat generated during compression is radiated to the outside and cooled to near room temperature, and then the opening of the regenerative heat exchanger 43. 43a.

Therefore, similarly to the first embodiment, the compression space 19 formed on the base end side of the compression cylinder 3 and the expansion space 11 formed on the expansion cylinder 2 are separated by gas through the regenerator material 14. Since they are communicated by the passage, the gas passage can be shortened, and the dead volume can be reduced and the device structure can be simplified. Further, the gas passages 32 and 46 have a large heat exchange area, and the working gas that has been compressed on the compressor side and has a high temperature is efficiently radiated by passing through the gas passages 32 and 46. Since it is formed in a narrow gap, the volume of the gas passage is reduced, the dead volume is reduced, the ratio of the working gas introduced into the expansion space to the total enclosed amount is increased, and a large compression ratio is obtained,
It allows the working gas to have a lower temperature during expansion.

The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope.
Further, the configuration of each part of the present invention is not limited to the above-described embodiment, but can be variously modified within the technical scope described in the claims. For example, the case where the present invention is applied to the Stirling refrigeration system has been described, but the present invention can also be applied to other gas compression expansion refrigeration systems.

[0039]

As described above, according to the present invention, the gas passage can be shortened, the dead volume can be reduced, the device structure can be simplified, and the entire device can be downsized.

Further, by providing the expansion side heat exchange means, the dead volume can be reduced and the heat radiation surface can be enlarged, the compression ratio can be increased and the refrigerating capacity of the device can be improved. Further, by providing the compression-side heat exchange means, the heat radiation capacity for extracting the high temperature generated in the compression space to the outside can be further improved, and the refrigeration capacity of the device can be further improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a Stirling refrigerating apparatus as a first example of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a schematic configuration of a Stirling refrigeration system as a second example of the embodiment of the present invention.

FIG. 3 is a cross-sectional view of a conventional Stirling refrigeration system.

FIG. 4 is a diagram illustrating a process of a Stirling refrigeration cycle.

[Explanation of symbols]

 2, 42 Expansion cylinder 3 Compression cylinder 5 Crank mechanism 6 Displacer 7 Compression piston 11 Expansion space 13, 19 Compression space 15 Cold head 18 Communication gas passage 20 Expansion side partition member 22, 46 Expansion side gas passage 24, 48 Expansion side heat exchange Means 30 Compression-side partition member 32 Compression-side gas passage 34 Compression-side heat exchange means 45 Expander body container

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takafumi Nakayama 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (5)

[Claims] 1. A gas passage connects a compression space formed in a compression cylinder arranged inside the compressor body container and an expansion space formed in an expansion cylinder arranged inside the expander body container. And a driving means for transmitting a driving force so that the compression piston and the expansion piston or the displacer reciprocally drive the compression cylinder and the expansion cylinder respectively with a predetermined phase difference. A refrigeration system for generating a low temperature by a heat cycle including an expansion process of a working gas guided from a space into the expansion space, wherein a base end side of the compression cylinder is a compression space, and the compression space and the base of the expansion cylinder. A refrigeration system characterized in that the end side is communicated with the gas passage. 2. A displacer for reciprocally driving the inside of the expansion cylinder, and an expansion side heat exchange means for exchanging heat with a working gas introduced into the displacer from the compression space, the expansion side heat exchange means comprising: The expansion-side partition member is disposed in the vicinity of the lower portion of the cylinder, and the expansion-side gas passage having a narrow cylindrical gap is formed between the lower portion and the expansion-side partition member. The refrigerating apparatus according to claim 1, wherein a high temperature generated in the compression space due to the passage of the working gas is extracted to the outside. 3. A compression side heat exchange means for exchanging heat with a working gas introduced into the displacer from the compression space, wherein the compression side heat exchange means is arranged near a lower portion of the compression cylinder. In the compression space, a partition member and a compression-side gas passage formed between the lower portion and the compression-side partition member and having a narrow cylindrical gap are provided, and the working gas passes through the compression-side gas passage. The refrigerating apparatus according to claim 2, wherein the generated high temperature is extracted to the outside. 4. An expansion piston which communicates the compression space and the expansion space with each other through a gas passage via a regenerative heat exchanger arranged on an outer peripheral surface of the expansion cylinder, and which reciprocally drives the inside of the expansion cylinder. An expansion side heat exchange means for exchanging heat with the working gas introduced into the regeneration heat exchanger from the compression space, wherein the expansion side heat exchange means is an expansion provided on an outer peripheral surface of a lower portion of the expansion cylinder. A side partition member, and an expansion side gas passage having a narrow cylindrical gap formed between the expansion side partition member and the expander main body container, wherein the working gas passes through the expansion side gas passage. The refrigerating apparatus according to claim 1, wherein the high temperature generated in the compression space is extracted to the outside. 5. A compression-side heat exchange means for exchanging heat with a working gas introduced into the regenerative heat exchanger from the compression space, the compression-side heat exchange means being disposed adjacent to a lower portion of the compression cylinder. A compression-side partition member, and a compression-side gas passage having a narrow cylindrical gap formed between the lower portion and the compression-side partition member. The refrigerating apparatus according to claim 4, wherein the high temperature generated in the compression space is extracted to the outside.