JPH10300252A - Stirling refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To connect a displacer, a spring and a flange part coaxially. SOLUTION: A hole 38c is provided coaxially in a spring retaining part 38 of a first spring fitting member 36 and a helical groove of the same pitch as a spring 33 is formed in the inner peripheral surface of the hole 38c. A hole 40c is provided coaxially in a spring retaining part 40 of a second spring fitting member 39 and the helical groove of the same pitch as the spring 33 is formed in the inner peripheral surface of the hole 40c. The first and second spring fitting members 36 and 39 can be bisected on a plane containing the axis. The opposite end parts of the spring 33 are held in by the first and second spring fitting members 36 and 39 being bisected and the divided surfaces are bonded together. A connecting part 37 of the first spring fitting member 36 made integral is screwed to a base end member 34 of a displacer 31, while a connecting part 41 of the second spring fitting member 39 is screwed to a flange part 32. The displacer 31, the spring 33 and the flange part 32 are connected coaxially in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an improvement of a Stirling refrigerator.

[0002]

2. Description of the Related Art Conventionally, there is a Stirling refrigerator as one of small refrigerators for cooling an atmosphere to an extremely low temperature. This Stirling refrigerator has a structure in which a compressor that compresses a refrigerant gas and an expander that expands the high-pressure refrigerant gas discharged from the compressor by reciprocating a displacer.

Hereinafter, the above Stirling refrigerator will be briefly described. FIG. 5 is a schematic sectional view of the Stirling refrigerator. The compressor 1 has a substantially symmetric structure with a plane including the axis of the refrigerant gas discharge hole 20 connected to the working chamber 17 of the expander 11 as a boundary.

In the compressor 1, a cylinder 3a having an outer peripheral surface along an inner peripheral surface of the casing 2 and a cylinder 3b having an axial hole 4 are provided at a central portion in the axial direction in a closed cylindrical casing 2. The connected double cylindrical cylinder 3 is housed.
A piston 5 having a disk 7 attached to one end is inserted into one end of the shaft hole 4 of the cylinder 3. Similarly, a piston 5 ′ having a disk 7 ′ attached to one end is inserted through the other end of the shaft hole 4. A compression chamber 6 is formed between the heads of the pistons 5, 5 '.

[0005] The coils 9, 9 'are formed on the outer peripheral surfaces of the cylinders 8, 8' extending from the outer peripheral edges of the discs 7, 7 'to the two cylinders 3a, 3b of the cylinder 3. This coil 9, 9 '
Together with the magnets 10 and 10 ′ provided at both ends of the outer peripheral surface of the cylinder 3 b of the cylinder 3, a linear motor is configured. Driven by the linear motor, the pistons 5, 5 'reciprocate synchronously with the assistance of the springs 21, 21'.

The expander 11 encloses a displacer 14 having a mesh-like cold storage material in a cylinder 12 having radiation fins 13 on the outer periphery, and seals the displacer 14 and the cylinder 12 with an annular sealing material 15. . Thus, the interior of the cylinder 12 is partitioned by the displacer 14 and the sealing material 15 into the expansion chamber 16 on the distal end side and the working chamber 17 on the proximal end side. The working chamber 17 communicates with the compression chamber 6 of the compressor 1 via a connection pipe 19. The base end of the displacer 14 is connected to the base end of the cylinder 12 by a spring 18 so that the displacer 14 is normally at a neutral position.

The above-structured Stirling refrigerator operates as follows. When the pistons 5, 5 'of the compressor 1 move in the axial hole 4 toward the center in the axial direction to compress the refrigerant gas in the compression chamber 6, the pressure in the working chamber 17 of the expander 11 increases. . Then, a pressure difference is generated between the working chamber 17 and the expansion chamber 16. When the pressure difference exceeds the elastic force of the spring 18, the displacer 14 moves toward the tip of the cylinder 12.

When the displacer 14 reaches the tip of the cylinder 12, the high-pressure refrigerant gas in the working chamber 17 flows toward the expansion chamber 16 while being cooled by the regenerator material in the displacer 14, and the working chamber 17 and the expansion chamber are eventually formed. 16 and the same pressure. Then, the displacer 14 moves to the base end side of the cylinder 12 by the contraction force of the spring 18 and returns to the neutral position.

Next, when each of the pistons 5, 5 'of the compressor 1 moves to the one end side or the other end side to decrease the pressure in the compression chamber 6, the pressure in the working chamber 17 is increased. 16
And the pressure difference between the two chambers 16 and 17 occurs. When the pressure difference exceeds the elastic force of the spring 18, the displacer 14 moves to the base end of the cylinder 12. As a result, the refrigerant gas in the expansion chamber 16 adiabatically expands, and the temperature decreases. The refrigerant gas thus cooled flows into the working chamber 17 while applying cold to the cold storage material in the displacer 14, and the working chamber 17 and the expansion chamber 16 have the same pressure. Then, the displacer 14 moves to the distal end side of the cylinder 12 by the extension force of the spring and returns to the neutral position.
Thus, one refrigeration cycle ends.

FIG. 6 is a detailed sectional view of the expander 11. As described above, the Stirling refrigerator includes a spring 18 supporting the displacer 14 in the expander 11.
This refrigerant gas is cooled by adiabatic expansion of the refrigerant gas due to the balance between the elastic force of the above and the pressure difference between the working chamber 17 and the expansion chamber 16. Therefore, it is necessary to reduce the sliding resistance when the displacer 14 reciprocates in the cylinder 12, and it is necessary to eliminate the inclination when the displacer 14-spring 18-cylinder 12 (flange portion 25) is assembled.

The spring 18 is mounted on the displacer 14 by attaching the spring 18 to the outer peripheral surface of a first spring mounting member 27 screwed into a shaft hole of a base member 26 of the displacer 14.
This is performed by screwing one end side of. Further, the spring 18 is attached to the flange 25 by screwing the other end of the spring 18 to the outer peripheral surface of the second spring attaching member 28 fitted to the seal portion 25a provided on the flange 25. Done.

[0012]

However, the above-mentioned conventional Stirling refrigerator has the following problems.
FIG. 7 shows a procedure for attaching the spring 18 to the displacer 14 and the flange 25. The attachment of the spring 18 to the displacer 14 and the flange 25 is performed as follows.

First, one end of the spring 18 is screwed into a spiral groove 27a having the same pitch as the spring 18 formed on the outer peripheral surface of the first spring mounting member 27, and
Screw. Similarly, a spiral groove 28a having the same pitch as the spring 18 formed on the outer peripheral surface of the second spring mounting member 28
Then, the other end side of the spring 18 is screwed into the spring 18 to screw the spring 18.

Then, a male screw 29a provided on the head 29 of the first screw mounting member 27 is screwed into a female screw 26b provided in a shaft hole 26a of the base member 26 of the displacer 14, and The shoulder 27b of the one spring mounting member 27 is fitted to the intaglio portion 30 of the base end member 26. Further, the other end side of the second spring mounting member 28 is fitted to a seal portion 25 a provided on the flange portion 25.

Incidentally, in the above-described structure for attaching the spring 18 to the displacer 14 and the flange portion 25, the spring 18 is provided in the spiral grooves 27a, 28a formed on the outer peripheral surfaces of the first and second spring attaching members 27, 28. Are screwed in at both ends. In that case, the first one of the springs 18 with respect to the first one round of the spiral grooves 27a, 28a
When screwing in the circumference, the spring mounting members 27 and 28 and the spring 18
And it is very difficult to keep them coaxial. for that reason,
A slight inclination easily occurs between the axes of the first and second spring mounting members 27 and 28 and the axis of the spring 18, and the spring 18 is forcibly screwed into the spiral grooves 27a and 28a of the spring mounting members 27 and 28. In this case, the spring 18 bites into the spiral grooves 27a and 28a. Thereafter, the spring 18 is screwed in while the axis of the spring 18 is inclined with respect to the axes of the first and second spring mounting members 27 and 28. As a result, the axis of the displacer 14 is It will be inclined with respect to the axis.

Therefore, in the above-described structure for attaching the spring 18 to the displacer 14 and the flange portion 25, the sliding resistance when the displacer 14 reciprocates in the cylinder 12 is increased, and the life is greatly reduced.
There is a problem that the refrigeration efficiency is reduced.

An object of the present invention is to provide a Stirling refrigerator in which the cylinders of the displacer-spring-expander are coaxially connected and the displacer has low sliding resistance.

[0018]

According to a first aspect of the present invention, there is provided a cylinder having a cylinder and a displacer which is reciprocally fitted in the cylinder to reciprocate the displacer. A Stirling refrigerator having an expander that expands a refrigerant gas supplied from a compressor to cool it to an extremely low temperature, wherein a spring mounted on one end of the displacer in the cylinder, and one end of the displacer Alternatively, it has a screw portion provided with a male screw to be screwed to one end of the cylinder, and a spring holding portion provided with a shaft hole, and can be divided into two parts by a surface including a shaft. A spring mounting member for holding the spring on the inner peripheral surface of the spring.

According to the above configuration, one end of the spring is sandwiched by the spring holding portion of the spring mounting member that is divided into two parts by the plane including the shaft. Then, the spring is held by the inner peripheral surface of the shaft hole in the spring holding portion. Therefore, an uneven external force is not applied to the spring in the radial direction, and the spring is coaxially mounted in the shaft hole of the spring mounting member. That is, if the screw portion of the spring mounting member is coaxially screwed into the cylinder of the displacer or the expander, the displacer-spring-cylinder is connected coaxially, and the sliding resistance of the displacer is reduced. .

According to a second aspect of the present invention, in the Stirling refrigerator of the first aspect, the inner peripheral surface of the shaft hole of the spring holding portion has the same pitch as the pitch of the spring. And a spiral groove in which the spring can be fitted.

According to the above configuration, the spring mounted in the shaft hole of the spring mounting member is fitted into the spiral groove formed on the inner peripheral surface of the shaft hole and securely fixed to the spring mounting portion. Is done. In this case, an uneven external force is not applied to the spring in the radial direction, and the spring is mounted in the shaft hole coaxially with the spring mounting member.

According to a third aspect of the present invention, in the Stirling refrigerator of the first aspect, the spring is
A spring main body having a predetermined outer diameter; and a different diameter portion formed at both ends of the spring main body and having an outer diameter larger than the spring main body. It is characterized in that a locking groove into which the diameter portion is fitted is formed.

According to the above configuration, the spring mounted in the shaft hole of the spring mounting member is securely fixed to the spring mounting portion by fitting the different diameter portion of the spring into the locking groove. . In this case, an uneven external force is not applied to the spring in the radial direction, and the spring is mounted in the shaft hole coaxially with the spring mounting member.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows a procedure for attaching a spring to a displacer and a flange in an expander of a Stirling refrigerator according to the present embodiment. In the present embodiment, as shown in FIG. 1B, a coil spring (hereinafter, referred to as a coil spring) that connects the displacer 31 and the flange portion 32 is provided.
The spring holding portion 38 of the first spring mounting member 36 is attached to one end of the spring 33. Similarly, the spring holding portion 40 of the second spring attachment member 39 is attached to the other end of the spring 33.

The male screw provided at the connecting portion 37 of the first spring mounting member 36 is screwed into the female screw provided at the shaft hole 35 of the base member 34 of the displacer 31.
The first spring mounting member 36 is mounted on the displacer 31. On the other hand, a male screw provided on the connecting portion 41 of the second spring mounting member 39 is screwed into a female screw provided on the shaft hole 42 of the flange portion 32, and the second spring mounting member 39 is mounted on the flange portion 32. Can be That is, in the present embodiment, the connection portion 37, 41 constitutes the screw portion.

In the first spring mounting member 36, as shown in FIG. 1A, a hole 38c having an inner diameter slightly smaller than the outer diameter of the spring 33 is coaxially provided in the spring holding portion 38. It can be divided into two by the plane including the axis. Similarly, the second spring mounting member 39 includes the first spring mounting member 3
A hole 40c having the same inner diameter as the hole 38c of the sixth hole is provided coaxially and can be divided into two by a plane including the axis.

When the one end of the spring 33 is mounted on the spring holding portion 38 of the first spring mounting member 36, the spring holding portions 38a and 38b of the first spring mounting members 36a and 36b are used. The divided surfaces of the first spring mounting members 36a and 36b are adhered with an adhesive while sandwiching the one end of the 33. Similarly, when attaching the other end of the spring 33 to the spring holding portion 40 of the second spring attachment member 39, the spring holding portion 4 of the second spring attachment member 39a, 39b divided into two parts.
0a and 40b sandwich the other end of the spring 33, and the second
The split surfaces of the spring mounting members 39a and 39b are bonded with an adhesive.

Then, the integrated first spring mounting member 3
6 is screwed to the base member 34 of the displacer 31, while the connecting portion 41 of the integrated second spring mounting member 39 is screwed to the flange 32. Thus, the first
By screwing the spring mounting member 36 and the second spring mounting member 39 to the base member 34 or the flange 32, the spring 33 temporarily held by the adhesive force of the adhesive is securely held. . As a result, the displacer 31, the spring 33, and the flange 32 are integrally connected.

FIG. 2 is a detailed sectional view of the first spring mounting member 36. FIG. 2B is a front view, and FIG. 2C is an assembly view. First split spring mounting member 36
holes 38c in the spring holding portions 38a and 38b of the respective a and 36b
Are formed on the inner peripheral surface of the spiral groove having the same pitch as the pitch of the spring 33 when the first spring mounting members 36a and 36b are attached. Then, the cross-sectional shape of the spiral groove 43 is made the same arc shape as the cross-sectional shape of the spring 33. By doing so, when the above-mentioned one end of the spring 33 is sandwiched by the spring holding portions 38a, 38b of the first spring mounting members 36a, 36b, the outer periphery of the spring 33 becomes the groove 43.
a, 43b are fitted into the spiral groove 43 formed by the spring 3
3 is attached to the first spring attachment member 36 so as not to come off.

In this case, the spring 33 is held by the spring holding portions 38a and 38b of the first split spring mounting members 36a and 36b.
No external force is applied to the spring 33 in the radial direction. Therefore, when the spiral groove 43 is formed, the pitch of the spiral groove 43 and the pitch of the spring 33 correctly match,
If the spiral groove 43, the hole 38c, and the connecting portion 37 are coaxial, the spring 33 is coaxially mounted on the first spring mounting member 36. As a result, it is coaxially attached to the displacer 31.

As described above, in the present embodiment, the spring holding portions 3 of the first split spring mounting members 36a and 36b are divided into two parts.
The one end of the spring 33 is sandwiched between the inner peripheral surfaces of the holes 38c in the holes 8a and 38b, and the outer peripheral portion of the spring 33 is fitted into the spiral groove 43 formed on the inner peripheral surface of the hole 38c. Is attached to the first spring attachment member 36. Therefore, the spring 33 can be mounted on the first spring mounting member 36 without applying an external force to the spring 33 in the radial direction, and the first spring mounting member 36 and the spring 33 can be coaxially connected. Further, according to the present embodiment, replacement of the spring 33 is facilitated, and maintainability is improved.

FIG. 3 is a sectional view showing the structure of the first spring mounting member different from FIG. FIG. 3B is a front view, and FIG. 3C is an assembly view. As shown in FIG. 3C, the first spring mounting member 51 includes a spring holding portion 5 for holding the spring 33 in the same manner as the first spring mounting member 36 shown in FIG.
2 and a connecting portion 53 connected to the base member 34 of the displacer 31, and can be divided into two parts by a plane including an axis.

The spring holding portion 5 of the first spring mounting member 51
2 has a hole 52 c having the same inner diameter as the outer diameter of the spring 33. When the one end of the spring 33 is attached to the first spring attachment member 51, the following is performed. The above-mentioned one end of the spring 33 is sandwiched between the spring holding portions 52a and 52b of the first split spring mounting members 51a and 51b, and the inner wall surface of the hole 52c of the spring holding portion 52 and the outer peripheral portion of the spring 33,
Then, the bonding surfaces of the first spring mounting members 51a and 51b are bonded with an adhesive. Thus, the spring 33 is attached to the first spring attachment member 51 so as not to come off.

In this case, the spring 33 is held by the spring holding portions 52a, 52b of the first split spring mounting members 51a, 51b.
No external force is applied to the spring 33 in the radial direction. Therefore, if the hole 52c of the first spring attachment member 51 is correctly coaxial with the connecting portion 53, the spring 33 is attached coaxially to the first spring attachment member 51.
As a result, it is coaxially attached to the displacer 31.

In the above embodiment, the inner wall surface of the hole 52c of the spring holder 52 and the outer peripheral portion of the spring 33 are bonded with an adhesive to fix the spring 33 to the first spring mounting member 51. ing. However, the method of fixing the spring 33 to the first spring mounting member 51 is not limited to this. For example, the inner diameter of the hole provided in the spring holding portion of the first spring mounting member is set to be slightly smaller than the outer diameter of the spring 33. Then, the two ends of the first spring mounting member are sandwiched and joined together by the spring holding portions of the first spring mounting member, so that the spring 33 is evenly tightened from the periphery by the spring holding portions. Thus, the spring 33 is fixed to the first spring mounting member by the reaction force of the above-mentioned tightening force by the spring 33.

According to this embodiment, it is not necessary to form a spiral groove on the inner peripheral surface of the hole 52c in the spring holding portion 52 of the first spring mounting member 51. Therefore, it is possible to reduce the troublesome spiral groove forming process and reduce the cost.

FIG. 4 is a cross-sectional view of a first spring mounting member different from FIGS. 2 and 3 and a diagram showing a structure of a spring mounted on the first spring mounting member. FIG. 4B is a front view, and FIG. 4C is an assembly view. The spring 66 in the present embodiment includes a spring main body 67 and a different diameter portion 68 formed by making the outer diameter of one end of the spring main body 67 larger than the outer diameter of the spring main body 67. .

On the other hand, as shown in FIG. 4C, the first spring mounting member 61 includes a spring holding portion 62 for holding the spring 66 and a displacer 31 similar to the first spring mounting member 51 shown in FIG. And a connecting portion 63 connected to the base member 34 of the spring 66, and a hole 64 having the same inner diameter as the outer diameter of the spring body 67 of the spring 66 is provided. And it can be divided into two by a plane including the axis.

In the first spring mounting member 61, the innermost peripheral surface of the hole 64 of the spring holding portion 62
A circular locking groove 65 having the same inner diameter as the outer diameter of the different diameter portion 68 of the spring 33 is provided. When the different-diameter portion 68 of the spring 66 is attached to the first spring attachment member 61, the following is performed. The one end of the spring body 67 is sandwiched between the holes 64a and 64b of the first split spring mounting members 61a and 61b, and the different diameter portion 68 is sandwiched between the locking grooves 65a and 64b. Then, the joining surfaces of the first spring attachment members 61a and 61b are adhered with an adhesive. Thus, the different diameter portion 68 of the spring 66
Is locked in the locking groove 65 of the first spring mounting member 61, and the spring 66 is mounted on the first spring mounting member 61 so as not to come off.

In this case, the spring 66 is held by the spring holding portions 62a and 62b of the first split spring mounting members 61a and 61b.
No external force is applied to the spring body 67 and the different-diameter portion 68 in the radial direction. Therefore, if the hole 64 and the locking groove 65 of the first spring mounting member 61 are correctly coaxial with the connecting portion 63, the spring 66 is coaxially mounted on the first spring mounting member 61. As a result, it is coaxially attached to the displacer 31.

In FIG. 4, the side wall of the locking groove 65 which forms the boundary between the hole 64 and the locking groove 65 in the first spring mounting member 61 is a plane perpendicular to the axis. By the way, spring 6
6, there is a large difference between the outer diameter of the spring body 67 and the outer diameter of the different diameter portion 68, and the transition from the spring body 67 to the different diameter portion 68 hits the side wall of the locking groove 65, so that the external force is applied to the transition. When it is applied, the spring 66 is inclined due to the external force. In this case, it is necessary to provide an inclination or a notch or the like on the side wall of the locking groove 65 such that the transition portion of the spring 66 does not abut, so that an uneven external force is not applied to the spring 66. .

According to this embodiment, it is not necessary to form a spiral groove on the inner peripheral surface of the hole 64 in the spring holding portion 62 of the first spring mounting member 61, and the spring 66 can be securely connected to the first spring. It can be fixed to the mounting member 61.

Although not described in detail, the specific configuration of the spring mounting portion of the second spring mounting member may be the same as that of the first spring mounting member. In the case of the second spring mounting member 39 shown in FIG. 1, the first spring mounting member 3 shown in FIG.
As in the case of No. 6, a spiral groove having the same pitch as the pitch of the spring 33 is formed when the second spring mounting members 39a and 39b are attached to the inner peripheral surface of the hole 40c in each of the spring holding portions 40a and 40b. A groove is formed. Here, the first
The spring mounting structure of the spring mounting member and the spring mounting structure of the second spring mounting member need not necessarily be the same.

Further, in the embodiment shown in FIG.
The second spring mounting member 39 is screwed to a flange 32 mounted to one end of a cylinder of the expander. However, the present invention is not limited to this, and it may be screwed to one end of the cylinder without a flange.

[0045]

As is apparent from the above description, the Stirling refrigerator according to the first aspect of the present invention has a screw portion provided with a male screw screwed to one end of a displacer or one end of a cylinder of an expander. It has a spring holding portion provided with a shaft hole, and has a spring mounting member which can be divided into two by a surface including a shaft, and the spring is sandwiched by an inner peripheral surface of the shaft hole, so that the spring is formed in the cylinder. Since the spring is mounted on one end side of the displacer, the spring is not subjected to an uneven external force in the radial direction, and the spring can be mounted coaxially in the shaft hole of the spring mounting member. That is, according to the present invention, each of both ends of the spring is coaxially sandwiched between the spring mounting members as described above, and the screw portions of the respective spring mounting members are coaxially screwed into the displacer or the cylinder. Thereby, the displacer-spring-cylinder can be connected coaxially. Therefore, the sliding resistance of the displacer can be reduced.

Further, the spring can be easily attached to and detached from one end of the displacer or the cylinder with high accuracy, and the maintainability can be improved.

According to a second aspect of the present invention, in the Stirling refrigerator, the inner periphery of the shaft hole of the spring holding portion has the same pitch as the pitch of the spring and the spiral can be fitted with the spring. Since the groove is formed, the spring coaxially held in the shaft hole of the spring mounting member is fitted into the spiral groove formed on the inner peripheral surface of the shaft hole, and is securely fixed to the spring mounting portion. it can.

In the Stirling refrigerator according to the third aspect of the present invention, the spring has a spring main body and different diameter portions formed at both ends of the spring main body with a diameter larger than that of the spring main body. The inner peripheral surface of the shaft hole of the member is formed with a locking groove into which the different diameter portion of the spring is fitted. Therefore, when the spring is mounted in the shaft hole of the spring mounting member, the different diameter portion is used. By fitting the spring into the locking groove, the spring can be coaxially held by the spring mounting portion and securely fixed.

[Brief description of the drawings]

FIG. 1 is a view showing a procedure for attaching a spring to a displacer and a flange in an expander of a Stirling refrigerator according to the present invention.

FIG. 2 is a sectional view and an assembly view of a first spring mounting member in FIG. 1;

FIG. 3 is a sectional view and an assembly view of a first spring mounting member different from FIG. 2;

FIG. 4 is a sectional view, an assembly view, and a structural view of a spring of a first spring mounting member different from FIGS. 2 and 3;

FIG. 5 is a schematic sectional view of a Stirling refrigerator.

6 is a detailed sectional view of the expander in FIG.

FIG. 7 is a diagram showing a procedure for attaching the spring in FIG. 6 to a displacer and a flange portion.

[Explanation of symbols]

31 displacer, 32 flange part, 33, 66 spring, 34 base end member, 36, 51, 61 first spring mounting member 37, 41, 5
3, 63 ... connecting part, 38, 40, 52, 62 ... spring holding part, 38c, 40c, 52c, 64 ... hole, 39 ... second
Spring mounting member, 43 ... spiral groove, 6
5 ... locking groove, 67 ... spring body, 68
… Different diameter part.

Claims (3)

[Claims] 1. A cylinder having a cylinder and a displacer (31) reciprocally fitted in the cylinder. The refrigerant gas supplied from the compressor is expanded by reciprocating the displacer (31). A Stirling refrigerator having an expander that cools to an extremely low temperature, comprising: a spring (33, 66) mounted on one end side of the displacer (31) in the cylinder; one end of the displacer (31) or A threaded part (3) provided with a male thread to be screwed to one end of the cylinder
7, 53, 63) and a spring holding portion (38, 52, 62) provided with a shaft hole (38c, 52c, 64), and can be divided into two by a plane including the shaft. Hole (38c, 52
A Stirling refrigerator comprising a spring mounting member (36, 51, 61) for sandwiching the spring (33, 66) on the inner peripheral surface of the (c, 64). 2. The Stirling refrigerator according to claim 1, wherein the inner peripheral surface of the shaft hole (38c) of the spring holding portion (38) has the same pitch as the pitch of the spring (33). , Spring above
A Stirling refrigerator comprising a spiral groove (43) into which (33) can be fitted. 3. The Stirling refrigerator according to claim 1, wherein the spring (66) has a predetermined outer diameter.
And a different diameter portion (68) having an outer diameter larger than that of the spring body (67) formed at both ends of the spring body (67), and a shaft hole (64) of the spring mounting member (61). An engagement groove (65) into which the different diameter portion (68) of the spring (66) is fitted
A Stirling refrigerator comprising: