JPH06129725A - Refrigerating machine - Google Patents

Abstract

PURPOSE:To obtain a refrigerating machine, whose vibration is small and not transmitted to the outside thereof, even when a movable part, constituted of a displacer, cold heat accumulating material and a control piston, is operated with reciprocating motion. CONSTITUTION:A balancer cylinder 29, a balancer cylinder 33 and a balancer 31, moved receprocally in the balancer cylinder 33, are arranged below a control piston 24 while a refrigerating machine is equipped with a cold finger 2 provided with a balancer chamber 30 partitioned from a control chamber 23 by the control piston 24, the balancer cylinder 29, the balancer 31 and the balancer cylinder 33. According to this method, the balancer is operated so as to cancel the reaction of vibration generated by the reciprocating motion of the movable unit constituted of the displacer, the cold heat accumulating material and the control piston whereby the generated vibration can be restrained effectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling refrigerator for cooling, for example, an infrared element or a superconductor to an extremely low temperature, generally 100K or less.

[0002]

2. Description of the Related Art FIG. 4 shows a configuration example of a conventional Stirling refrigerator. The Stirling refrigerator shown in FIG. 4 is called a split type Stirling refrigerator, and is a typical example of the Stirling refrigerator. In FIG. 4, the split Stirling refrigerator is roughly divided into a compressor 1, a cold finger 2, and a connecting pipe 3 connecting them.

The compressor 1 comprises a cylinder 4 and a piston 5, and the piston 5 is reciprocated inside the cylinder 4 by being driven by an electric motor though not shown in the figure via a connecting rod 6 and a crank 7. Has become. A cylinder head 8 is attached to the upper portion of the cylinder 4, and the internal space defined by the cylinder head 8 is called a compression chamber 9. A mechanical member for driving the piston 5 such as the crank 7 is housed in a housing 10 and
The housing 10 partitioned from the compression chamber 9 by
The inner space is called a bulk chamber 11. The cylinder 4, the cylinder head 8 and the housing 10 are joined to each other so as to maintain airtightness with the outside, and the compression chamber 9 and the bulk chamber 11 inside are filled with a high-pressure working gas such as helium and hydrogen. Has been done. A piston ring 12 is attached to the side surface of the piston 5 so that the working gas does not pass through the clearance between the piston 5 and the cylinder 4. Further, fins 13 are provided on the outer surface of the cylinder 4 in order to enhance heat radiation to the outside. The above is the configuration of the compressor 1. On the other hand, the cold finger 2 has a displacer 15 which slidably reciprocates in a cylindrical low temperature cylinder 14. The space inside the low-temperature cylinder 14 is divided into two by the displacer 15. The space above the displacer 15 is called a low temperature chamber 16 and the space below is called a high temperature chamber 17. The displacer 15
A regenerator 18 and a gas passage hole 19 are provided inside, and the low temperature chamber 16 and the high temperature chamber 17 are continuous through the regenerator 18 and the gas passage hole 19. The cold storage material 20 is filled. A seal 21 is fitted on the side surface of the displacer 15 so that the working gas does not pass through the clearance between the low temperature cylinder 14 and the displacer 15. The displacer 15
A control chamber 24 surrounded by a control piston 24, a control cylinder 22 and a housing 27 is provided at the lower end of the control piston 24. The control piston 24 passes through the high temperature chamber 17 and the control cylinder 22 and projects into the control chamber 23. ing. A seal 25 is attached to the control cylinder 22 so that the working gas does not pass through the clearance between the control cylinder 22 and the control piston 24. Similar to the compressor 1, each chamber of the cold finger 2 is filled with a high-pressure working gas such as helium or hydrogen. The above is the configuration of the cold finger 2, and the compression chamber 9 of the compressor 1 and the high temperature chamber 17 of the cold finger 2 communicate with each other through the connecting pipe 3. Also, the compression chamber 9,
The space inside the connecting pipe 3, the low temperature chamber 16, the high temperature chamber 17, the regenerator 18, and the gas passage hole 19 communicate with each other, and these chambers as a whole are collectively called a working chamber 26.

The operation of the conventional refrigerator configured as described above will be described. The piston 5 reciprocates in the cylinder 4 to give a sinusoidal wave to the gas pressure in the working chamber 26 from the compression chamber 9 to the low temperature chamber 16. on the other hand,
Since the volume of the bulk chamber 11 is sufficiently larger than the stroke volume of the piston 5, the internal gas pressure does not change much even when the piston 5 reciprocates. The seal 25 attached to the control cylinder 22 of the cold finger 2 almost completely seals against a pressure change of a short cycle such as the pressure wave of the gas in the working chamber 26 described above, but seals in a long time. Is incomplete, the gas pressure in the control chamber 23 is maintained at an average value of the gas pressure in the working chamber 26.

FIG. 5 to FIG. 8 explain the operation principle of the conventional apparatus in the order of the refrigeration cycle. In the course of the cycle shown in FIG. 5, the piston 5 of the compressor 1 is located below the cylinder 4 and the displacer 15 of the cold finger 2 is located above the cold cylinder 14. 5 to 6, the piston 5 rises to compress the gas in the working chamber 26. Working chamber 2 at the time of FIG.
The gas pressure of 6 is higher than the gas pressure in the control chamber 23, and the downward force generated in the control piston 24 by this differential pressure moves the displacer 15 downward by overcoming the static friction force of the seals 21 and 25. First, as shown in FIG. 7, the cold cylinder 14 is moved to the lower part. With the movement of the displacer 15, the gas in the high temperature chamber 17 moves to the low temperature chamber 16 through the regenerator 18, and at this time, the regenerator material 20 charged in the regenerator 18 absorbs heat from the passing gas to generate the gas. Lower the temperature. In the process from FIG. 7 to FIG. 8, the piston 5 of the compressor 1 descends to expand the gas in the working chamber 27, and the gas in the low temperature chamber 16 further drops in temperature due to this expansion, and the heat from the surroundings of the upper part of the cold finger 2 is increased. Absorbs. This endothermic action plays a role of cooling off the object to be cooled as a refrigerator. Since the pressure in the working chamber 26 decreases due to the expansion of the gas, the gas pressure in the control chamber 23 is higher than that in the working chamber 26 at the time of FIG. The force exerted upwardly on the control piston 24 by this pressure difference counteracts the static frictional force of the seals 21 and 25, causing the displacer 15 to start moving upward and to the upper portion of the cold cylinder 14 as shown in FIG. This displacer 1
With the movement of 5, the low temperature gas in the low temperature chamber 16 passes through the regenerator 18, stores cold heat in the regenerator material 20 in the regenerator 18, and the gas itself flows into the high temperature chamber 17 while increasing the temperature. The refrigerating operation is performed by repeating the above cycle.

[0006]

The conventional device as described above has the following problems. There has been a problem that the reaction force of the vibration generated when the movable part composed of the displacer, the regenerator material and the control piston reciprocates is directly transmitted to the housing to generate a large vibration outside.

The present invention has been made in order to solve the above problems, and is provided with a balancer for canceling a reaction force of vibration generated when a movable portion composed of a displacer, a regenerator material and a control piston reciprocates. The purpose is to suppress the vibration generated when the unit reciprocates.

[0008]

In the refrigerator of the present invention, a balancer cylinder A, a balancer cylinder B, and a balancer inside the balancer cylinder B are arranged below the control piston, and the control piston, the balancer cylinder A, and the balancer cylinder B are arranged.
Has a balancer chamber separated from the control chamber, and a seal is provided so that the working gas does not pass through the gap between the control piston and the balancer cylinder A and the gap between the balancer and the balancer cylinder B.

[0009]

In the present invention, as shown in FIG. 2, when the displacer moves upward, the working gas in the balancer chamber expands and becomes lower than the gas pressure in the control chamber. The downward pressure exerted on the balancer by this pressure difference overcomes the frictional force of the seal to start moving the balancer downward, and moves to the lower part of the balancer cylinder B. As shown in FIG. 3, when the displacer moves downward, the working gas in the balancer chamber is compressed and becomes higher than the gas pressure in the control chamber. The force exerted upwardly on the balancer by this differential pressure strikes against the frictional force of the seal and starts moving the balancer upward, and moves to the upper part of the balancer cylinder B. Therefore, the balancer operates in the same cycle, in the same phase, and in the opposite direction as the displacer, so that the reaction force of the vibration generated from the movable portion composed of the displacer, the regenerator material and the control piston is canceled and the vibration is suppressed.

[0010]

1 is a sectional view showing an embodiment of the present invention, in which a compressor 1 and a connecting pipe 3 are exactly the same as those of a conventional device, and a cold finger 2 is a balancer cylinder below a control piston 24. A29, balancer cylinder B33, balancer 31 that reciprocates inside balancer cylinder B33
The control piston 24 and the balancer cylinder A29.
A balancer chamber 30 separated from the control chamber 23 by a balancer 31 and a balancer cylinder B33 is provided. Further, unlike the conventional device, seals 28 and 32 are provided so that the working gas does not pass through the gap between the control piston 24 and the balancer cylinder A29 and the gap between the balancer 31 and the balancer cylinder B33. is there.

The refrigerator of the invention as described above has the same principle as that of the conventional refrigerator, but when the displacer 15 moves upward, the pressure in the balancer chamber 30 is higher than that in the control chamber 23. Since it becomes smaller, the balancer 31 moves to the lower part of the balancer cylinder B33. When the displacer 15 moves downward, the pressure in the balancer chamber 30 becomes higher than the pressure in the control chamber 23, so that the balancer 31 moves to the upper part of the balancer cylinder B33. Therefore, the balancer 31 operates in the same cycle, in the same phase, and in the opposite direction as the displacer 15, so that the reaction force of the vibration generated from the movable portion constituted by the displacer 15, the regenerator material 20, and the control piston 24 is canceled and the balancer 31 vibrates. Can be suppressed.

[0012]

As described above, according to the present invention, since the balancer operates so as to cancel the reaction force of the vibration generated when the movable part composed of the displacer, the regenerator material and the control piston reciprocates, the movable part is operated. This has the effect of suppressing the vibration that occurs when the robot reciprocates.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view for explaining the principle of the balancer of the invention.

FIG. 3 is a sectional view for explaining the principle of the balancer of the invention.

FIG. 4 is a cross-sectional view showing the structure of a conventional device.

FIG. 5 is a cross-sectional view for explaining the operation principle of a conventional refrigerator.

FIG. 6 is a cross-sectional view for explaining the operation principle of a conventional refrigerator.

FIG. 7 is a cross-sectional view for explaining the operation principle of a conventional refrigerator.

FIG. 8 is a cross-sectional view for explaining the operation principle of a conventional refrigerator.

[Explanation of symbols]

 1 Compressor 2 Cold Finger 3 Connection Pipe 14 Low Temperature Cylinder 15 Displacer 16 Low Greenhouse 17 High Greenhouse 21 Seal 22 Control Cylinder 23 Control Room 24 Control Piston 25 Seal 26 Working Room 27 Housing 28 Seal 29 Balancer Cylinder A 30 Balancer Room 31 Balancer 32 Seal 33 Balancer cylinder B

Claims (1)

[Claims] 1. A compressor for giving periodic pressure fluctuations to a working gas in a working chamber, a slender cylindrical low-temperature cylinder, an interior of the low-temperature cylinder divided into a low-temperature chamber and a high-temperature chamber, and the inside of the low-temperature cylinder. A reciprocating displacer,
A control piston provided under the displacer, a control cylinder, a housing, a seal provided in a gap between the low temperature cylinder and the displacer, and a gap between the control cylinder and the control piston, and the housing. A cold finger having a control chamber partitioned by the control cylinder and the control piston, and a refrigerator constituted by a connecting pipe that connects the compressor and the high temperature chamber of the cold finger to each other, in the refrigerator. Balancer cylinder A provided at the bottom
A balancer cylinder B disposed below the balancer cylinder A, a balancer that reciprocates in the balancer cylinder B and divides the control chamber into a balancer chamber, the balancer cylinder A and the control piston. And a seal provided in the gap between the balancer cylinder B and the balancer.