JP2003294332A - Stirling refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly adjust pressure of a back pressure chamber 154 and a gas passage 175 even when operating over a long time. <P>SOLUTION: The gas passage 175 and the back pressure chamber 154 are communicated, and a pressure regulator 86 is arranged for adjusting a flow rate of operating gas flowing between these members. Thus, when differential pressure between the gas passage 175 and the back pressure chamber 154 becomes an improper state when operating over a long time, the differential pressure is adjusted by operating the pressure regulator 86. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling refrigerating machine capable of suppressing a decrease in refrigerating efficiency even when operated for a long time.

[0002]

2. Description of the Related Art Stirling refrigerators can be miniaturized,
High coefficient of performance and high refrigeration efficiency, wide temperature range generated,
It has many excellent features such as easy replacement of CFCs in recent global environmental problems.

For this reason, commercial or domestic cold heat utilization equipment such as freezers, refrigerators, and throw-in coolers, low-temperature liquid circulators, low-temperature incubators, constant-temperature baths, heat shock test equipment, freeze dryers, temperature characteristics Application to cold heat utilization equipment in all industrial fields such as test equipment, blood / cell storage equipment, cold cooler, and various other heat and cold equipment is being studied.

FIG. 3 shows such a Stirling refrigerator 5.
1 is a diagram showing a schematic configuration of No. 01, which includes a drive device 511 that includes a motor 514 to generate rotational power, and a cold heat generation unit 533 that is driven by the drive device 511 to generate cold heat.

The cold heat generating section 533 has a power converting section 534 for converting rotational power into reciprocating power, and an expanding section 590 having an expanding piston 593 for reciprocating in the expansion cylinder 597 by this reciprocating power to expand the working gas. A compression part 564 provided with a compression piston 567 that reciprocates in the compression cylinder 568 by reciprocating power to compress the working gas, and a heat storage part 674 that stores heat of the working gas flowing between the expansion part 590 and the compression part 564. Etc. are the main components.

The power conversion unit 534 has a crank housing 535 having a crank space 536 inside, and a crank shaft 537 connected to the motor shaft 517, a crank 538 attached to the crank shaft 537, and one end thereof. Connecting rod 54 connected to crank 538
1, a cross guide head 544 connected to the other end of the connecting rod 541, the cross guide head 54
Cross guide liner 5 that restricts the movement direction of 4 to one direction
47 etc. are provided.

Further, the expansion portion 590 is composed of the expansion piston 59.
Expansion cylinder 597 for accommodating 3 and expansion cylinder 59
7, an expansion space 592 provided on the head side, an expansion piston rod 600 for transmitting a driving force to the expansion piston 593, and the like.

The compression section 564 includes a compression cylinder 568 for accommodating the compression piston 567, a compression space 566 provided on the head side of the compression cylinder 568, and a compression piston 567.
It has a compression piston rod 569 that transmits the driving force to the.

Then, the compression space 566 and the expansion space 592.
Are connected to each other by a gas channel 675, and this gas channel 67
5, a heat storage unit 674 made of a cold storage material is provided.

With this structure, when the motor 514 is driven and the crank 538 rotates, the rotational power is converted into reciprocating power and transmitted to the compression piston 567 and the expansion piston 593, which reciprocate.

The expansion piston 593 advances in phase with the compression piston 567 by about 90 degrees and moves.

Oil 748 is used to suppress wear of movable parts such as the motor shaft 517, the crank 538 and the crank shaft 537, and the connecting rod 541 and the cross guide head 544. The oil 748 is the bottom of the crank space 536. It is stored in.

When the crank 538 moves, the oil 748 is scraped up and adheres to the movable part to lubricate the movable part.

However, when such oil 748 adheres to the expansion piston 593 and the compression piston 567,
Along with these reciprocating motions, there is a disadvantage that they gradually enter the compression space 566 and the expansion space 592 and mix with the working gas, or carbonize due to heat to reduce the refrigeration efficiency.

Therefore, an oil seal bellows 649 is provided between the cross guide head 544 and the compression piston 567 and the expansion piston 593.

The upper end of the oil seal bellows 649 has an expansion piston rod 600 and a compression piston rod 5.
69 is airtightly attached, and the lower end is airtightly attached to the crank housing 535.
0 and the reciprocating motion of the compression piston rod 569 causes the oil seal bellows 649 to expand and contract.

Therefore, the crank space 536 includes a room on the side of the compression piston 567 and the expansion piston 593 (this room is referred to as a back pressure chamber 654) and a room on the side of the crank 538 (this room is referred to as the crank space 536 again) by the oil seal bellows 649. It will be divided into two rooms.

Therefore, the oil 748 bounced up by the crank 538 cannot enter the back pressure chamber 654, and can prevent the inconvenience of adhering to the expansion piston 593 and the compression piston 567 and entering the compression space 566 and the expansion space 592. It is like this.

However, since the oil seal bellows 649 expands and contracts as the compression piston and the expansion piston reciprocate, the pressure in the back pressure chamber 654 fluctuates.

Since this pressure fluctuation increases the motor load and reduces the refrigeration efficiency, a communication hole 609 for communicating the gas passage 675 and the back pressure chamber 654 is provided, and the back pressure chamber 154 and the gas passage 154 are provided. And the pressure is even.

[0021]

However, at the initial stage such as when the apparatus is installed, the back pressure chamber 15 is set by the communication hole 609.
Even if the pressure adjustment between the No. 4 and the gas flow passage is properly performed, there is a problem in that the pressure adjustment is not properly performed during long-time operation.

Therefore, it is an object of the present invention to provide a Stirling refrigerator in which the pressure between the back pressure chamber and the gas passage can be properly adjusted even when operating for a long time.

[0023]

In order to solve the above-mentioned problems, the invention according to claim 1 reciprocates between a crank housed in a crank housing for converting rotational power of a motor into reciprocating power and a compression cylinder. A compression piston for compressing the working gas in the compression space, an expansion piston for reciprocating in the expansion cylinder to expand the working gas in the expansion space, and a working space for communicating the compression space and the expansion space with each other. In a Stirling refrigerator having a gas flow path that allows the gas to flow back and forth and an oil seal bellows that divides the crank housing into a crank space on the crank side and a back pressure chamber on the piston side, the gas flow path and the back pressure A pressure regulator that communicates with the chamber and regulates the flow rate of the working gas flowing between them is provided, so that the back pressure chamber and the gas flow passage And an object thereof with improved to reliability can be performed force adjustment properly.

The invention according to claim 2 is characterized in that the pressure regulator is a needle valve.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of a Stirling refrigerator applied to the description of the present embodiment, and the Stirling refrigerator mainly includes a cold heat generating unit that generates cold heat and a drive device that drives the cold heat generating unit. .

The drive unit 11 has a motor housing 12 having a motor chamber 13 inside, and a motor 14 composed of a stator 15 and a rotor 16 capable of rotating in the forward and reverse directions is installed in the motor chamber 13 so that rotational power is generated by the motor. It is output via the shaft 17.

The cold heat generating section 33 includes a power converting section 34 for converting the rotational power generated by the drive device 11 into reciprocating power, a compressing section 64 for compressing the working gas, an expanding section 90 for expanding the working gas, and a compression space 66. A heat storage unit 174 that is provided in a gas flow path 175 that communicates with the expansion space 92 and that stores the heat of flowing working gas, and a heat radiating unit 193 that radiates the heat of the working gas that has been compressed by the compression unit 64 and has increased in temperature to the outside. A cold head portion 219 that supplies cold heat generated by the expansion of the working gas in the expansion portion 90 to the cold heat utilization equipment, and an oil seal portion that prevents oil 248 in the crank space 36 from entering the compression space 66 and the expansion space 92. 148, a pressure adjusting unit 125 that suppresses the generation of a differential pressure between the back pressure chamber 154 and the crank space 36, and the like.

The power converter 34 has an internal crank space 3
6 has a crank housing 35, and the crank housing 35 is provided in contact with the motor housing 12 via the motor housing top 19.

At the bottom of the crank housing 35, oil 248 that lubricates the sliding portion of the power conversion unit 34 and the like.
Is stored, and the stored amount is a viewing window 50 made of a transparent member such as glass formed on the bottom side of the crank housing 35.
Can be confirmed by.

An oil passage hole 20 is formed on the bottom side of the motor housing top 19 to connect the motor chamber 13 and the crank space 36.

As a result, the oil 248 is also supplied to the motor chamber 13.
Is stored, and the motor chamber 13 and the crank space 36 are stored.
The atmosphere with can be exchanged with each other.

The motor housing 12 and the crank housing 35 are each sealed with a lid, and the motor housing 12, the crank housing 35, and the motor housing top 19 are manufactured by casting.

Therefore, the motor housing 12, the crank housing 35, and the motor housing top 19 can be cast as one body, and in this case, there is an advantage that the manufacturing cost can be reduced.

In such a Stirling refrigerator 1, helium, hydrogen, nitrogen or the like can be used as a working gas, and in this case, it should be sealed in the crank space, the motor chamber, the buffer tank, etc. Is preferred.

This is because the atmosphere in the crank space, the motor chamber, and the buffer tank slightly intrudes into the compression space and the expansion space due to long-time operation.

In the crank space 36, a crank shaft 37 connected to the motor shaft 17, a crank 38 composed of a compression crank 38a and an expansion crank 38b mounted on the crank shaft 37, and a compression connecting end connected to the crank 38. A connecting rod 41 including a rod 41a and an expansion connecting rod 41b, a cross guide head 44 including a compression cross guide head 44a and an expansion cross guide head 44b connected to the other end of the connecting rod 41, and the cross guide head 4
Cross guide liner 4 that restricts the movement direction of 4 to one direction
7 etc. are provided.

The compression crank 38a and the expansion crank 38b are provided eccentrically with respect to the shaft center of the crankshaft 37, and when the motor 14 rotates in the normal direction, the expansion crank 38a.
b is provided so as to rotate in advance of the compression crank 38a by approximately 90 degrees in phase.

Here, the forward rotation of the motor 14 refers to the direction of rotation of the motor 14 during the cycle operation that produces cold heat.

At this time, a balancer 51 is provided in order to suppress the rotational imbalance caused by the phase difference between the expansion crank 38b and the compression crank 38a.

The cross guide liner 47 is a substantially cylindrical hole into which the cross guide head 44 is inserted, and is formed by punching the top of the crank housing 35.

As a result, the cross guide head 44 driven by the crank 38 is guided by the cross guide liner 47 to reciprocate.

A fixed plate 243 is provided on the crank housing 35, and a cylinder housing 74 is provided on the fixed plate 243.

The cylinder housing 74 includes an upper cylinder housing 74a and a lower cylinder housing 74b.
And the lower cylinder housing 74b.
Through the fixed plate 243 to the crank housing 3
5 is bolted to the upper cylinder housing 74a
Is fixed to the lower cylinder housing 74b with bolts.

The compression portion 64 is the lower cylinder housing 7
4b, a compression cylinder 68 formed by making a hole, a compression piston 67 reciprocating in the compression cylinder 68, one end swingably attached to the compression cross guide head 44a, and the other end fixed to the compression piston 67. , A compression piston rod 69 connecting them, and the compression piston 67
Compression space 6 formed by the head side of the cylinder and the compression cylinder 68
Have six.

A compression piston ring 70 is attached to the side cylindrical surface of the compression piston 67 to keep the compression space 66 airtight.

The inflating section 90 is provided in the lower cylinder housing 7
4b and the upper cylinder housing 74a are bored to form an expansion cylinder 97, the inside of which is a hollow expansion cylinder 9
7, an expansion piston 93 that reciprocates in one end, one end of which is swingably attached to the expansion cross guide head 44b and the other end of which is fixed to the expansion piston 93, and the expansion piston rod 100 that connects them, and the expansion piston 93. Has an expansion space 92 formed by the head side of the expansion cylinder 97 and the expansion cylinder 97.
9 is formed.

The expansion cylinder 97 and the expansion piston 9
3 are respectively divided into upper and lower parts, and the upper expansion cylinder 9
7a, lower expansion cylinder 97b, upper expansion piston 93
a, a lower expansion piston 93b.

When mounting the lower expansion cylinder 97b in the lower cylinder housing 74b, the lower expansion cylinder 9b
7b is cooled by liquid nitrogen or the like and press-fitted by a method such as cold fitting to be mounted.

As a result, the lower expansion cylinder 97b is completely fixed to the lower cylinder housing 74b, so that inconvenience such as abnormal noise is prevented.

An expansion piston ring 104 is attached to the lower expansion piston 93b to keep the expansion space 92 airtight.

Further, the upper end portion of the lower expansion piston 93b and the lower end portion of the upper expansion piston 93a are formed so as to be integrally screwed together to form an expansion piston 93.

FC material, FCD material, etc. are used as the material of the lower cylinder housing 74b, but the leakage of working gas, the manufacturing cost and the member cost, and the sliding wear characteristics of the compression piston ring 70 and the expansion piston ring 104 are used. From the viewpoint of the above, FC300 is preferable.

Although steel is generally used as the material of the lower expansion cylinder 97b, SUS is preferable from the viewpoint of facilitating manufacturing and improving sliding wear characteristics of the expansion piston ring 104, particularly SUS303, S.
US 304 is preferred.

The surface roughness of the cylinder surfaces of the expansion cylinder 97 and the compression cylinder 68 is conventionally Rz at the lathe processing level.
Although it is about 5.0 microns, in the present invention, this is Rz.
The level is set to 3.0 μm or less, preferably Rz 1.0 μm or less.

As a result, the degree of progress of wear of the compression piston ring 70 and the expansion piston ring 104 is significantly reduced.

In the upper cylinder housing 74a and the lower cylinder housing 74b, there is formed a gas passage 175 of a narrow tube which connects the expansion space 92 and the compression space 66.

An annular groove 108 is formed so as to surround the lower end of the lower expansion piston 93b.
The gas flow path 175 is connected to 08 and communicates with the compression space 66.

On the other hand, the annular groove 108 communicates with the back pressure chamber 154 via a pressure regulator 86 such as a needle valve,
The annular groove 108 is adjusted by adjusting the pressure adjuster 86.
The pressure between the back pressure chamber 154 and the back pressure chamber 154 is adjusted.

In this way, the annular groove 1 is adjusted by the pressure regulator 86.
08 (that is, the gas flow path 175) and the pressure between the back pressure chamber 154 are adjusted by the Stirling refrigerator 1.
Operating for a long time, it may be difficult to adjust the pressure between the annular groove 108 and the back pressure chamber 154 in the conventional communication hole 609, and such a state may occur irregularly. Because there is.

The following causes can be considered as a cause of such a phenomenon. That is, the compression piston 67 and the expansion piston 93 are attached with the compression piston ring 70 and the expansion piston ring 104, and these abut against the compression cylinder 68 and the expansion cylinder 97 to slide, thereby compressing the compression space 66 and the expansion space. The airtightness between 92 and the back pressure chamber 154 is maintained.

Since the compression piston 67 and the expansion piston 93 have the same structure, the compression piston 67 will be described as an example in the following description.

The pressure regulator 86 regulates the differential pressure between the gas flow passage 175 and the back pressure chamber 154, but since the gas flow passage 175 communicates with the compression space 66 and the expansion space 92, the following description will be given. In the above, the operation and effect of the pressure adjuster 86 will be described assuming that the differential pressure between the compression space 66 and the back pressure chamber 154 is adjusted.

FIG. 2 is a view showing the relationship between the compression piston ring 70 and the compression cylinder 68 with respect to the movement of the compression piston 67. In FIG.
2 (b), the compression piston 67
Is moving to the back pressure side, Fig. 2 (c) and Fig. 2 (d)
The foreign matter P is the compression piston ring 70 and the compression piston 6.
The figure shows the case where it has entered between 7 and.

In FIG. 2, the solid line arrow indicates the compression piston 6.
The movement direction of 7 and the dotted arrow are the compression space 66 or the back pressure chamber 15
The flow of the atmosphere from 4, the double arrow indicates the cylinder contact force F1 that presses the compression piston ring 70 against the compression cylinder 68, and the alternate long and short dash line indicates the piston contact force F2 that presses the compression piston ring 70 against the compression piston 67. Is shown.

The compression piston ring 70 is mounted in the piston ring groove 77, but at that time, the compression piston ring 70 is not acted on by the force to positively contact the compression cylinder 68.

However, the compression piston 67 does not move into the compression space 66.
Side (FIG. 2A) or the compression piston 67 moves to the back pressure side, the working gas compressed in the compression space 66 or the atmosphere (working gas) compressed in the back pressure chamber 154.
Penetrates between the compression piston ring 70 and the piston ring groove 77 to press the compression piston ring 70 toward the compression piston 67 side and the compression cylinder 68 side.

As a result, the compression piston ring 70 and the compression piston 67 and the compression piston ring 70 and the compression cylinder 68 are airtightly in close contact with each other, and the compression space 66 and the back pressure chamber 15 are provided.
And 4 are airtightly divided.

Therefore, in such a case, the gas flow path 17
5 and the back pressure chamber 154 can always maintain a constant pressure relationship, and the purpose can be achieved by providing the communication hole 609 as in the related art.

However, when the construction is operated for a long time, the compression piston ring 70 is abraded, and the abrasion dust is generated as shown in FIGS. 2 (c) and 2 (d). If it enters into the gap 67, the cylinder abutting force F1 may not act, or in the worst case, both the cylinder abutting force F1 and the piston abutting force F2 may no longer act.

As a result, the pressure balance between the compression space 66 and the back pressure chamber 154 changes, and it becomes impossible to adjust the communication hole 609 which is set so that the foreign matter P does not exist.

In particular, this unadjustable amount changes depending on the size and amount of the foreign matter P, the place of entry, etc., and the movement of the foreign matter P renders it unadjustable or ameliorated.

Therefore, in the conventional communication hole 609,
In some cases, the pressure cannot be adjusted properly.

Therefore, in the present invention, as described above, the gas flow passage 175 and the back pressure chamber 154 are communicated with each other, and the pressure regulator 86 such as a needle valve is provided so that the flow rate of the working gas flowing through the bottom can be regulated. ing.

As a result, the pressure difference between the back pressure chamber 154 and the compression space 66 (gas passage 175) can be adjusted so as to be always in an optimum state, so that the refrigerating efficiency is lowered even after long-term operation. It becomes possible to prevent it.

Further, at the lower end of the upper cylinder housing 74a, a cylindrical heat storage material storage groove 105 is formed in the longitudinal direction so as to communicate with the gas flow passage 175, and a heat storage material 176 to be described later is inserted. It is like this.

The heat storage section 174 has a cylindrical heat storage material 176 made of a mesh-shaped metal sheet made of brass or stainless steel. A large number of the heat storage materials 176 are stacked and mounted in the heat storage material storage groove 105. To be done.

When the working gas expanded in the expansion space 92 and having a lowered temperature flows toward the compression space 66, the cold heat of the working gas is stored and the cold heat is expanded from the compression space 66. It is used to cool the working gas flowing to 92.

When the working gas that has been compressed in the compression space 66 and has increased in temperature flows from the compression space 66 toward the expansion space 92, the heat of the working gas is stored and the heat is expanded. Used to heat the working gas flowing from the compressed space 66 to the compressed space 66.

The heat radiating portion 193 is provided mainly for the purpose of promptly releasing the heat of the working gas, which has been compressed by the compressing portion 64 and has risen in temperature, to the outside, and circulates around the compression space 66 and the expansion cylinder 97. The cooling water passage 194 thus formed is formed in the lower cylinder housing 74b, and the radiator 195 having fins is provided at the lower end of the expansion cylinder 97.

In the Stirling refrigerator 1 according to the present invention, when the crank 38 rotates, the oil 248 stored in the bottom of the crank space 36 is scraped up, and the sliding portion between the crank 38 and the connecting rod 41 and the like. The sliding portions of the cross guide head 44 and the cross guide liner 47 are attached to lubricate these sliding portions.

At this time, the reciprocating motion of the cross guide head 44 causes the oil 248 to adhere to the compression piston 67 and the expansion piston 93, which are reciprocated by the compression piston 67 and the expansion piston 93 to cause the compression space 66 and the expansion space 92.
Is fed to the tank and causes a decrease in refrigeration efficiency.

Therefore, the oil 248 is compressed by the compression piston 67.
In order to prevent the oil seal bellows from adhering to the expansion piston 93 or the oil expansion bellows 93, the oil seal part 1 mainly composed of an oil seal bellows
48 are provided.

Such an oil seal portion 148 includes the fixed plate 243, the expansion piston 93 and the compression piston 6.
7, an oil seal bellows 149, a washer-shaped upper mounting ring 150 to which the upper end of the oil seal bellows 149 is welded, the oil seal bellows 14
It has a washer-shaped lower mounting ring 151 to which the lower end of 9 is welded.

As the oil seal bellows 149, a metal forming bellows integrally formed by pressing a metal material or a metal welding bellows assembled by welding is used.

The upper mounting ring 150 is mounted in close contact with the compression piston rod 69 or the expansion piston rod 100, and the lower mounting ring 151 is mounted in close contact with the lower cylinder housing 74b via the fixing plate 243.

As a result, the back pressure chamber 154 becomes airtight and the oil 248 from the crank space 36 is compressed into the compression space 66.
Thus, the inconvenience of entering the expansion space 92 can be completely prevented.

The back pressure chamber 154 is formed on each of the back pressure side of the compression piston 67 and the back pressure side of the expansion piston 93, and the back pressure chamber communicating hole 155 is formed so that they communicate with each other.
Are formed.

By the way, the space volume on the crank space 36 side is sufficiently larger than the space volume of the back pressure chamber 154.

The space volume on the crank space 36 side is
Since the crank space 36 and the motor chamber 13 communicate with each other, they are the sum of these.

When the back pressure chamber 154 is in an airtight state under such a volume relationship, the expansion piston 93 and the compression piston 6 are
Due to the reciprocating operation of No. 7, a large pressure fluctuation is generated in the back pressure chamber 154, and a large pressure difference is generated between the back pressure chamber 154 and the crank space 36.

When the pressure in the back pressure chamber 154 becomes higher than the pressure in the crank space 36, the oil seal bellows 14
When the pressure in the back pressure chamber 154 becomes lower than the pressure in the crank space 36, the oil seal bellows 149 expands in a bidal shape.

Such a deformation is repeatedly generated in the oil seal bellows 149 and is easily damaged.

Further, since the pressure fluctuation in the back pressure chamber 154 acts as a brake for the reciprocating motion of the expansion piston 93 and the compression piston 67, the load on the motor 14 increases correspondingly and the refrigeration efficiency decreases.

Therefore, a back pressure chamber communication hole 155 is provided to communicate the back pressure chambers 154 formed on the back pressure side of the compression piston 67 and the back pressure side of the expansion piston 93, respectively.

Since the compression piston 67 and the expansion piston 93 reciprocate while maintaining a predetermined phase difference, their back pressure side pressure also fluctuates while maintaining a predetermined phase difference.

Therefore, by connecting the back pressure side of the compression piston 67 and the back pressure side of the expansion piston 93 through the back pressure chamber communication hole 155, the pressure fluctuations are mutually absorbed.

However, even with such a structure, the pressure is completely reduced due to the difference in space volume between the back pressure side of the compression piston 67 and the back pressure side of the expansion piston 93, the flow resistance of the atmosphere filling the back pressure chamber 154, and the like. Unable to absorb fluctuations.

For this reason, the pressure adjusting portion 125 having the buffer tank 126 is provided.

The buffer tank 1 of the pressure adjusting unit 125
26 includes a pressure adjusting bellows 127 that airtightly divides the space in the tank into two spaces. One space communicates with the back pressure chamber 154 by the back pressure side communication pipe 128, and the other space communicates with the crank side communication pipe 130. Communicates with the crank space 36 and the motor chamber 13.

A space communicating with the back pressure chamber 154 is referred to as a back pressure side buffer chamber 129, and a space communicating with the crank space 36 is referred to as a crank side buffer chamber 131.

At least the back pressure side buffer chamber 12
The space volume of 9 is sufficiently larger than the space volume of the back pressure chamber 154.

As the pressure adjusting bellows 127, a metal forming bellows or a metal welding bellows can be used similarly to the oil seal bellows 149. However, since the expansion and contraction amount is not so large as that of the oil seal bellows 149, it is possible to use a resin. It is also possible to use a rubber bellows.

As a result, the pressure fluctuation in the back pressure chamber 154 is automatically alleviated by the pressure fluctuation in the back pressure side buffer chamber 129, and is absorbed by the expansion and contraction of the pressure adjusting bellows 127, so that the back pressure chamber 154 and the crank space 36 are separated from each other. Between the oil seal bellows 1
It is possible to prevent deterioration and destruction of the 49, and improve the operation performance and durability of the Stirling refrigerator 1.

Since the motor chamber 13 communicates with the crank space 36, the same effect can be obtained even if the crank side buffer chamber 131 communicates with the motor chamber 13.

The cold head portion 219 is provided with the cooling fins 2.
20 and a jacket 221 provided so as to enclose the tip portion of the cooling fin 220, and the brine flow path 2 is provided between the cooling fin 220 and the jacket 221.
22 is formed.

As the brine, ethyl alcohol, HFE, PFC, PFG, nitrogen, helium, etc. can be used.

As a result, the brine is cooled by the cooling heat generated in the expansion space 92 via the cooling fins 220, and the cooling heat is supplied to the equipment utilizing cold heat.

Next, the operation of the Stirling refrigerator 1 having such a configuration will be described.

When the motor 14 is driven, its rotational power is transmitted to the crankshaft 37 via the motor shaft 17.

A crank 38 is eccentrically attached to the crankshaft 37, and a cross guide head 44 is connected to the crank 38 via a connecting rod 41. Therefore, the rotational power is the reciprocating power of the cross guide head 44. To be converted.

When the cross guide head 44 reciprocates, the expansion piston 9 connected through the piston rod.
3 and the compression piston 67 reciprocate to compress the working gas,
Expands.

At this time, the oil 24 is applied by the crank 38.
8 adheres to the cross guide head 44 and the like, but the crank space 36 and the back pressure chamber 1 are prevented by the oil seal bellows 149.
54 and 54 are completely partitioned.

Further, the pressure difference between the back pressure chamber 154 and the expansion space 92 is adjusted by the buffer tank 126 to suppress the generation of the pressure difference between them. At this time, the pressure adjusting bellows 127 is used. Since the buffer tank 126 is partitioned by the buffer tank 126, the oil 248 does not flow from the crank space 36 or the like into the back pressure chamber 154 via the buffer tank 126.

Therefore, the oil 248 does not enter the back pressure chamber 154 and does not enter the compression space 66 and the expansion space 92, and the reduction of refrigeration efficiency can be prevented.

Since the buffer tank 126 suppresses the differential pressure between the back pressure chamber 154 and the expansion space 92, the load on the motor 14 is reduced, and the reduction in refrigeration efficiency can be suppressed.

In this way, when the expansion piston 93 and the compression piston 67 reciprocate and the expansion piston 93 approaches the top dead center and becomes slow in movement, the compression piston 67 moves rapidly near the middle toward the top dead center. As a result, the working gas is substantially adiabatically compressed and its temperature rises.

The compressed working gas flows through the gas passage 175 and flows into the heat radiating portion 193, where it radiates heat to the cooling water via the radiator 195 to lower the temperature.

The working gas radiated to the cooling water is stored in the heat storage unit 17
4 flows into the heat storage material 4 and passes through the heat storage material 176.
The warm heat is stored in 76 and flows into the expansion space 92.

Then, the compression piston 67 approaches the top dead center, and its speed becomes slow.

Then, the expansion piston 93 rapidly moves toward the bottom dead center, whereby the expansion space 92 expands rapidly, and the working gas in the expansion space 92 adiabatically expands and cools.

As a result, the temperature of the cold head portion 219 is lowered, the brine is cooled through the cooling fins 220, and cold heat is supplied to the cold heat utilization equipment.

When the expansion piston 93 moves from the bottom dead center to the top dead center, the compression piston 67 is moving from the intermediate position toward the bottom dead center, whereby the working gas is expanded.
2 to the compression space 66 through the gas flow path 175.

At this time, the working gas, which has expanded and decreased in temperature, stores cold heat in the heat storage material 176 and flows into the compression space 66 via the heat radiating portion 193 to complete one cycle.

Then, when such a cycle operation is carried out for a long time and the adjustment between the back pressure chamber 154 and the gas flow passage 175 is not properly performed, the pressure regulator 86 is operated to bring the pressure to an appropriate pressure. adjust.

As a result, it becomes possible to prevent the refrigeration efficiency from deteriorating even during long-term operation.

[0126]

As described above, according to the present invention,
Since a pressure regulator that connects the gas flow passage and the back pressure chamber and adjusts the flow rate of the working gas flowing between them is provided, the back pressure chamber and the gas flow passage The pressure can be adjusted properly and the reliability is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a Stirling refrigerator applied to the description of an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of a compression piston ring.

FIG. 3 is a side view of a Stirling refrigerator applied to the description of the conventional technique.

[Explanation of symbols]

1 Stirling refrigerator 33 Cold heat generator 66 compression space 67 Compression piston 68 compression cylinders 70 Compression piston ring 77 Piston ring groove 86 Pressure regulator 92 Expansion space 93 Expansion piston 93a Upper expansion piston 93b Lower expansion piston 97 expansion cylinder 97a Upper expansion cylinder 97b Lower expansion cylinder 104 expansion piston ring 108 annular groove 149 oil seal bellows 175 gas flow path F1 Cylinder contact force F2 Piston contact force P foreign material

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[Procedure amendment]

[Submission date] July 9, 2002 (2002.7.9)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

With such a structure, when the motor 514 is driven and the crank 538 rotates, the rotational power thereof is converted into reciprocating power and transmitted to the compression piston 567 and the expansion piston 593, which reciprocate.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

The drive unit 11 has a motor housing 12 having a motor chamber 13 inside, and a motor 14 composed of a stator 16 and a rotor 15 is installed in the motor chamber 13 so as to rotate forward and backward. It is output via the shaft 17.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction content]

FC material, FCD material or the like is used as the material of the lower cylinder housing 74b. From the viewpoints of prevention of working gas leakage, manufacturing cost and member cost, sliding wear characteristics of the compression piston ring 70, etc. Is preferred.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0090

[Correction method] Change

[Correction content]

When the back pressure chamber 154 is in an airtight state under such a volume relationship, the expansion piston 93 and the compression piston 6 are
Due to the reciprocating motion of 7, a large pressure fluctuation is generated in the back pressure chamber 154, and a large pressure difference is generated between the back pressure chamber 154 and the crank space 36.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0113

[Correction method] Change

[Correction content]

The pressure difference between the back pressure chamber 154 and the crank space 36 is adjusted by the buffer tank 126,
Generation of a differential pressure is suppressed between them, but at this time, the pressure adjustment bellows 127 is used to
Therefore, the oil 248 does not flow into the back pressure chamber 154 from the crank space 36 and the like via the buffer tank 126.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0115

[Correction method] Change

[Correction content]

Since the buffer tank 126 suppresses the pressure fluctuation in the back pressure chamber 154, the load on the motor 14 is reduced and the reduction in refrigeration efficiency can be suppressed.

[Procedure Amendment 7]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure Amendment 8]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

[Procedure Amendment 9]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Sekiya             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd.

Claims (2)

[Claims] 1. A crank housed in a crank housing for converting rotational power of a motor into reciprocating power, a compression piston for reciprocating in a compression cylinder to compress working gas in a compression space, and a reciprocating in an expansion cylinder. An expansion piston that moves to expand the working gas in the expansion space; a gas flow path that connects the compression space and the expansion space to allow working gas to move between them; In a Stirling refrigerator having an oil seal bellows partitioned into a crank space on the crank side and a back pressure chamber on the piston side, an operation of communicating the gas flow path and the back pressure chamber and flowing between them A Stirling refrigerator, which is provided with a pressure regulator that regulates a gas flow rate. 2. The Stirling refrigerator according to claim 1, wherein the pressure regulator is a needle valve.