JPH09292163A - Oil seal device of gas compression/expansion unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple seal device capable of preventing intrusion of oil of a driving part into a working part. SOLUTION: Cross guide spaces 45a, 45b are provided between a partition part and cross guides 42a, 42b reaching the top death center so as to eliminate adhesion of oil to partition parts 50a, 50b, intermediate chambers 51a, 51b of prescribed dimensions are provided between a driving part 40 and working parts 20, 30 to increase the length of the intrusion passage of oil, and partition parts 53a, 53b between the intermediate chamber and the working part are arranged so that the pressure fluctuation of the working part is attenuated in the process in which the gas flows through the clearance inside, or the thickness of the seal is increased to make the clearance P longer and to take time for the gas to flow therethrough. Seal devices (labyrinth seal) 55a, 55b of non- contact structure which prevent the fluctuating pressure from being applied to an oil seal part 52 are provided to prevent intrusion of oil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil seal device for a gas compressor / expander which compresses or expands gas by reciprocating a piston.

[0002]

2. Description of the Related Art Conventionally, gas compressors / expanders have been used in Stirling refrigerators, Stirling engines, reciprocating compressors and the like.

FIG. 8 shows a schematic structure of such a gas compression / expansion machine. The gas compression / expansion machine 100 has a working part 110 having a piston 111 for compressing / expanding a working gas by the piston 111, and a driving part 120 for giving a driving force to the piston 111, and these are a partition part 130.
Are classified by In addition, the crank mechanism 121 provided in the drive unit 120 includes a connecting rod 12
The cross guide 123 is connected via 2.

The piston 111 and the cross guide 12
Numeral 3 is connected by a rod 140 that passes through the partition 130, and the rotational movement of the crank mechanism 121 is converted into a reciprocating movement and transmitted to the piston 111. As a result, the working gas in the working unit 110 is compressed or expanded by the reciprocating motion of the piston 111.

The crank mechanism 121 is lubricated with oil 124. When the oil 124 enters the working portion 110 and mixes with working gas, the working gas passage is clogged with oil. For this reason, the partition portion 130 is provided with a sealing material 131 that is fitted into the rod 140, and the oil 124 adhering to the rod 140 is wiped off by rubbing against the rod 140.

FIG. 9 is a sectional view of a portion where the sealing material 131 is arranged. The seal material 131 is used for the seal storage unit 1.
32, and the rod 1
It is biased to the 40 side. As described above, the sealing material 13
The sealing effect of the sealing material 131 and the rod 140
It is achieved by wiping off the oil 124 adhered by the rubbing of the sealing material 131. Therefore, in order to sufficiently wipe off the oil 124, it is necessary to urge the sealing material 131 with a strong backup force.

[0007] However, such a method of removing the oil 124 has a problem that the sealing material 131 is worn out when used for a long time, and the sealing effect is reduced.

When the cross guide 123 reaches the top dead center, the distance between the cross guide 123 and the partition 130 is short, and the oil 124 adhering to the cross guide 123 is short.
However, the partition portion 130 comes into contact with the partition portion 130, a large amount of the partition portion 130 adheres thereto, and enters the seal portion.

Further, the oil 124 attached to the reciprocating cross guide 123 is removed by the sealing material 131 due to the inertial force.
Or the oil 124 accumulates between the cross guide 123 and the partition 130 due to long-time operation, and the oil 124 is kicked off by the cross guide 123 toward the seal material 131.

When the above-mentioned situation occurs, the reciprocating motion of the rod 140 causes the oil 124 to be gradually fed to the working portion 110 side, and finally enters the working portion 110 to be mixed with working gas, and the gas compression / expansion device concerned. Performance will be reduced. Therefore, it renders the device unusable. That is, the life of the device is determined by these factors.

[0011]

Therefore, the present invention solves the above problems and prevents oil from being mixed into the working gas by adopting a sealing device capable of improving the sealing performance, thereby achieving high reliability. Another object of the present invention is to provide an oil seal device for a gas compression / expansion machine having a long life.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an operating portion for reciprocally accommodating a piston to which one end of a rod is connected, and a cross guide connected to the other end of the rod. An oil seal device for a gas compression / expansion machine, which has a drive unit that houses a drive mechanism that reciprocates along a cross guide guide unit, and a partition that partitions the operation unit and the drive unit through which the rod is inserted. In, the dimension between the partition and the cross guide reaching the top dead center is larger than the thickness of the oil adhering to the cross guide, and the cross guide space is accumulated in the cross guide space. An oil returning means for returning oil to an oil tank provided under the drive mechanism; and a rod provided inside the partitioning portion including the rod, and having a predetermined length in the axial direction of the rod. An intermediate chamber formed to have a dimension in the radial direction of the rod larger than the thickness of oil attached to the rod; an oil seal portion provided in a partition wall portion between the intermediate chamber and the cross guide space; Is provided in the partition wall portion with respect to the working portion side with a clearance from the rod, and the pressure fluctuation on the working portion side is attenuated so as not to be transmitted to the intermediate chamber side, so that the fluctuating pressure is not applied to the oil seal portion. And a non-contact seal having a structure capable of preventing the above.

In the non-contact seal, a large number of ring-shaped seal pieces are arranged in the rod axial direction, and a large number of the seal pieces formed between the seal element pieces are continuously provided in the rod axial direction. A labyrinth seal having a structure having a plurality of space parts, and a gas maze in which the gas flowing between the intermediate chamber and the operating part is sequentially accumulated through the clearance between the tip of the sealing piece and the rod peripheral surface in these space parts. Is characterized in that.

Further, the non-contact seal has a structure in which a pair of seal pieces that are separated from each other in the axial direction of the rod and face each other are provided, and a single gas reservoir space is formed between the seal pieces. Characterize.

Furthermore, an operating portion for reciprocatingly accommodating a piston to which one end of the rod is connected and a drive mechanism for reciprocating a cross guide connected to the other end of the rod along the cross guide guiding portion. Drive unit to store,
In a gas compressor / expander oil seal device having a partition part through which the rod is inserted and which partitions the operating part and the drive part, a dimension between the partition part and the cross guide reaching a top dead center. Is a cross guide space formed larger than the thickness of the oil attached to the cross guide,
An oil returning means for returning the oil accumulated in the cross guide space to an oil tank provided in the lower part of the drive mechanism, and the rod provided inside the partitioning portion, and having a predetermined length in the axial direction of the rod. An intermediate chamber having a dimension in the radial direction of the rod larger than the thickness of the oil adhering to the rod, and an oil seal portion provided in the partition wall portion between the intermediate chamber and the cross guide space. A non-contact seal provided in the partition wall portion of the intermediate chamber with the working portion side, the non-contact seal being provided with a clearance, the non-contact seal having a seal wall length passing through the clearance. It is characterized in that it is formed to have a length such that the gas flow transmitted from the operating part side to the intermediate chamber becomes difficult and the pressure fluctuation is attenuated.

The dimension of the intermediate chamber in the radial direction of the rod means the dimension from the surface of the rod, and the oil thickness means the thickness of the oil adhering to the cross guide and the rod when there is a distribution. Means maximum thickness.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a Stirling refrigerator when the oil seal device according to the present invention is applied to a displacer type Stirling refrigerator. In the following description, upper, lower, left, and right directions may be defined. However, these directions generally indicate the directions in FIG. 1, and in other cases, the directions are described. For the reference numerals, for example, the cross guide 42
When (42a, 42b) is described, number 42 is number 4
Each of 2a and 42b is a general number.

The Stirling refrigerator 10 includes a compression section (operating section) 20 having a compression piston 21, a displacer 3
1 and a drive unit 40 having a crank mechanism 41, and a compression unit 20.
The displacer portion 30 and the displacer portion 30 are communicated with each other through a gas flow path 60.

The compression piston 21 has a rod 49a.
And the rod 49a is connected to the cross guide 42a of the drive unit 40 through the partition 50a.
Similarly, the displacer 31 is connected to the rod 49b,
The rod 49b is inserted through the partition 50b and
Is connected to the cross guide 42b.

The displacer 31 is provided with a regenerator 33, and the regenerator 33 is made of a material having a large specific heat, for example, a regenerator material such as copper, lead, stainless steel wire mesh or sphere.

The cross guide 42 (42a, 42b) is
The cross guides 43 are guided by cross guides 43 (43a, 43b), and the cross guides 42 are connected by connecting rods 44.
It is connected to the crank mechanism 41 via (44a, 44b).

A crank mechanism 41 provided in the drive unit 40
Is transmitted to the cross guide 42 via the connecting rod 44. At this time, the two connecting rods 44a and 44b receive the driving force from the crank mechanism 41 at the same point of action. This causes the compression piston 21 and the displacer 31 to operate synchronously.

A cross guide space 45 is provided between the cross guide 42 and the partition 50 in order to avoid contact between them.
(45a, 45b) are provided. This prevents contact between the partition 50a and the oil adhering to the cross guide 42a reaching the left end dead center, and contact between the oil and the partition 50b adhering to the cross guide 42b reaching the top dead center. .

The dimension of the cross guide space 45 in the axial direction of the rod 49 is set to be larger than the thickness of the oil 46 attached to the surface of the cross guide 42 to which the rod 49 is connected.

Since the displacer portion 30 is provided upright, the surface of the cross guide 42b to which the rod 49b is connected can be approximated to a substantially horizontal surface, and thus the oil 46 attached to the surface can be approximated. Can be considered to be uniform in thickness. However, since the compression section 20 is disposed in the horizontal direction, the oil 46 is urged by the cross guide 4 due to gravity.
2a is gathered on the lower side, and the adhering oil 4
A distribution occurs in the thickness of No. 6. Accordingly, in such a case, the thickest portion of the oil 46 is the thickness of the oil 46.

A crank mechanism 41 is provided under the drive unit 40.
An oil tank 47 is provided in which oil 46 for lubricating the oil is stored. The side surface of the cross guide 42b on the side of the depressor section 30 is partially cut away to form an oil return space 48b.
The dotted line area in FIG. 5 indicates a cutout area.

The oil return path 4 is provided in the cross guide guide portion 43a.
8a, and an oil return gap 48b is provided in the cross guide 42b.
Is provided for the following reason. That is, in the present embodiment, since the displacer section 30 is disposed in the upright state, the oil 46 in the cross guide space 45b can be dropped from the oil return gap 48b by gravity and returned to the oil tank 47. The arrow in FIG. 5 shows the flow of the oil dropped in this way.

On the other hand, since the compression section 20 is arranged laterally, the oil 46 in the cross guide space 45a cannot return to the oil tank 47 due to gravity. For this reason, an oil return path 48a passing through the inside of the cross guide guide 43a is provided so that the oil 46 accumulated in the cross guide space 45a is returned to the oil tank 47.

The shape of the oil gap is not limited to that shown in FIG. 5, but the side surface of the cross guide 42b may be grooved, or the cross guide guide portion may be grooved. It may be.

Now, inside the partition 50, the rod 49
(49a, 49b) to include the intermediate chamber 51 (51a,
51b) is provided.

The partition walls 56a, 56 between the intermediate chambers 51a, 51b and the cross guide spaces 45a, 45b.
Oil seal parts 52 (52a, 52b) are provided in b, respectively. Further, in the partition wall portions 53a and 53b between the intermediate chambers 51a and 51b and the operating portions 20 and 30,
Gas seal portions 55 (55a, 55b) are provided respectively.

Now, here, the intermediate chamber 51 has its length L1 in the rod direction made longer than the stroke length S of the rod 49 on / from which the oil film adheres to / from the drive unit 40. As a result, the oil film attached to the rod 49 cannot reach the partition wall portion 53 on the operating portion side, so that the oil film is prevented from entering the operating portion.

The dimension L2 of the intermediate chamber 51 in the radial direction of the rod 49 is made larger than the thickness of the oil 46 adhering to the rod 49 located in the intermediate chamber 51, and the oil is in the intermediate state due to the capillary phenomenon. It adheres to the cylindrical surfaces 54a, 54b of the chamber and is prevented from reaching the partition walls 53a, 53b by wrapping around.

In the intermediate chamber 51 having such dimensional conditions, even if the oil seal portion 52 has a clearance with the rod 49, the oil adhering to the rod 49 is limited to a thin oil film having this clearance. The oil film does not come into contact with the partition wall portion 53 even if it enters the intermediate chamber 51, and there is a sufficient distance between the operating portions 20 and 30, and it is impossible to reach the operating portion at all, and the oil does not reach the operating portions 20 and 30. It is possible to prevent contamination.

Therefore, as the oil seal portion 52, it is possible to use an oil seal of a type in which there is a minute gap between the seal wall and the rod 49 and there is no fear of non-contact wear.

Further, as the constitution of the device, the operating parts 20, 3
When the pressure fluctuation of 0 is applied to the oil seal portion 52 and the clearance of the oil seal portion 52 is large, the drive portion 40
Since there is a possibility that oil will flow into the intermediate chamber 51 from the above, it is sealed by the gas seal portion 53 so that fluctuations in gas pressure from the operating portions 20, 30 side are not transmitted to the intermediate chamber 51 side. The gas seal portion 55 and the oil seal portion 52 are made of PTFE (polytetrafluoroethylene) or the like.

By providing the intermediate chamber 51 having the above-mentioned structure, an oil seal having clearance with the rod 49 can be applied to the oil seal portion 52.

The intermediate chambers 51a and 51b and the operating portion 2
Gas seal parts 55 (55a, 55b) are provided on the partition wall parts 53a, 53b between 0 and 30, so that the oil seal part 52 is not subjected to fluctuating pressure, and there is a clearance with the rod 49. Even with an oil seal structure, no oil will enter.

As for the gas seal portion 53, the gas seal urged by the backup material on the rod as in the conventional case can obtain a high sealing effect, but the seal wears out after a long period of use and the sealing performance deteriorates. There is a problem to do.

The present invention is directed to an improved gas seal portion in consideration of this point, and has a resistance action against a gas flow which is going to be connected due to pressure fluctuation from the working portion side to the intermediate chamber side. It is provided in a non-contact state with the rod and is simple in terms of equipment so that it can be activated to reduce the transmission of pressure fluctuations in the operating part to the intermediate chamber side, and to exert a long sealing performance to prevent oil intrusion. The purpose is to provide a gas seal portion that can be formed, and the details thereof will be described later.

The Stirling refrigerator 10 of this embodiment is constructed as described above, and the driving force is transmitted from the crank mechanism 41 to the compression piston 21 and the displacer 31 by the rotation of the drive motor (not shown).

At this time, since the compression piston 21 and the displacer 31 are arranged orthogonally to each other, the compression portion 2
When the 0-side connecting rod 44a is substantially horizontal, the compression piston 21 hardly moves, but the displacer 31 moves the most. Conversely, when the connecting rod 44b on the displacer section 30 side is substantially vertical, the displacer 31 hardly moves, but the compression piston 21 moves the most. Thus, the compression piston 21 and the displacer 31 are synchronously moved out of phase.

Next, the Stirling refrigerator 10 having the above structure
Will be described. As described above, the compression piston 2
It should be added that the compression process and the expansion process, which will be described later, cannot be strictly distinguished because the phases of 1 and the displacer 31 are out of phase.

When the compression piston 21 moves from the left end dead center to the right end dead center, the working gas in the working space 22 of the compression section 20 is isothermally compressed by the compression piston 21.

During this time, the displacer 31 moves upward, and then moves downward after reaching the top dead center. The working gas compressed with the upward movement of the displacer 31 is sent to the displacer section 30 side through the gas passage 60, and the displacer 3
When 1 moves down, the working gas passes through the regenerator 33, radiates heat to the regenerator 33, and is sent to the expansion space 32.

As the displacer 31 reaches the bottom dead center, the compression piston 21 moves from the right end dead center to the left end dead center, and the working gas expands to lower the temperature. Since the expansion process at this time is an isothermal expansion process, external heat is absorbed as much as the temperature is reduced by the expansion. That is, it can be cooled.

As the compression piston 21 approaches the left end dead center, the displacer 31 starts to move upward, the working gas passes through the displacer 31, absorbs heat from the regenerator 33, and
The cycle ends.

Stirling refrigerator 1 for performing the above cycle
When the oil 46 is mixed with the working gas at 0, the cooling efficiency is reduced. To prevent the oil from entering, the drive unit 40
A cross guide space 45 is provided in front of the partition to prevent oil from adhering to the partition itself. In addition, means such as provision of an intermediate chamber 51 having a length such that the oil attached to the rod does not come into contact with the partition wall portion 53 on the operating portion side is provided.

By doing so, it is possible to use the oil seal portion 52 which is sealed by a seal material having a clearance and does not have a fear of deterioration of sealing performance due to wear.

Further, the gas seal portion 55 provided on the partition wall portion 53 prevents the oil seal portion 52 from being subjected to a fluctuating pressure and prevents oil from entering through the clearance with the rod. In order to improve the gas sealing property, it is advantageous to use a backup material for the gas sealing portion 52 and to urge the rod 49 with a strong force, but the sealing portion 55 will be significantly worn due to long-term use and the sealing will be improved. There is a problem that the force is reduced and the above-described clearance that facilitates oil entry is generated.

When the gas sealability is deteriorated, the pressure fluctuations of the operating parts 20 and 30 are largely transmitted to the intermediate chamber 51, so that the oil from the drive part 40 is significantly invaded.
That is, the intrusion of oil through the clearance is greatly affected by pressure fluctuations from the operating portions 20, 30 side.

FIG. 6 shows pressure fluctuations in the intermediate chamber 51, the operating parts 20, 30 and the drive chamber 40. As described above, in the operating parts 20, 30, the working gas is compressed / compressed by the piston 21 or the displacer 31. Since it is expanded, the pressure in the operating parts 20 and 30 periodically fluctuates, and similarly, the intermediate chamber 5
The pressure of 1 also fluctuates periodically. Furthermore, the pressure fluctuation is
This affects the gas seal portion 52 and causes oil to enter.

Therefore, when the oil enters, the operating portion 20,
Since the pressure fluctuation applied to the oil seal part 52 from 30 through the intermediate chamber 51 has a great influence, the gas seal part 55
It is preferable that the (55a, 55b) block the variable pressure from the operating sections 20, 30 so as not to be transmitted to the intermediate chamber 51 side, and the gas seal section has good durability because the blocking property is long and can be held well.

By the way, in such a gas seal device, the pressure fluctuations from the operating parts 20 and 30 are transmitted as a gas flow passing through the gap between the seal part and the rod, so that it becomes a resistance to the passage of the gas and it takes time to pass the gas. With such a structure, the transmission of the fluctuating pressure is delayed, and a high effect of preventing oil intrusion can be obtained.

The present invention focuses on the above points, and the gas seal portion 55 (55a, 55b) is designed to store the passing gas in the space provided therein, and to keep the fluctuating pressure for the accumulated time. (EN) Provided is an oil seal device capable of effectively preventing oil from entering by adopting a configuration capable of reducing the influence or a configuration in which a gas passage itself formed by a clearance is elongated.

A specific example will be described below. As can be understood from FIG. 2 which is an enlarged view of the oil seal portion 55a surrounded by a circle A in FIG.
The partition walls 53a and 53b through which the
9. A non-contact type oil seal part 55 (55a, 5a, 5a, 55a, 55a,
5b) is formed.

In this way, the oil seal portion 55 (55a, 5a, 5a, 5a, 5a, 5a) having a structure formed by arranging a large number of seal pieces 80 side by side
5b), voids 81 are formed between the seal pieces 80 and the seal pieces 80, and since there are these gaps 81, the pressure fluctuations generated in the operating portions 20 and 30 become the gas flow. Even if the gas flow is transmitted to the intermediate chamber 51 side, a large number of the seal pieces 80 of the oil seal portion 53 are arranged in parallel.
The pressure fluctuation is attenuated while passing through the gap 81 between the seal element 80 and the seal element 80, and the fluctuation pressure applied to the oil seal part 52 that seals the drive part 40 is reduced. You can

As described above, the gas seal portion 55 is thus formed.
When a pressure difference between the operating parts 20, 30 and the intermediate chamber 51 is transmitted as a gas flow, the passage formed by a large number of continuous voids 81 inside the chamber becomes a gas maze 90 for the gas flow, and the operating part 20 , 30 has a function of attenuating the pressure fluctuations in the process of being transmitted to the intermediate chamber 51, so that it is possible to prevent the fluctuation pressure from being applied to the oil seal portion 52.

As a result, oil can be effectively prevented from entering through the oil seal portion 56. Since this gas seal portion 55 has a clearance with the rod 49, even if it is operated for a long time, the seal will wear like a seal urged by a conventional backup material, resulting in a large clearance and The problem of deterioration of the sealing property is eliminated, a long-life gas sealing portion can be obtained, and the reliability of the device is improved.

Further, since the fluctuating pressure applied to the oil seal portion 55 can be reduced in this way, even if the oil seal portion 52 having a clearance with the rod is used, the invasion of oil can be prevented, and there is no practical problem. If a backup material is not needed like an oil seal with this clearance, the seal itself is simple, and it is easy to install and the cost of parts can be reduced.

The use of a labyrinth seal, which is a sealing device having a large number of voids 81 inside and a gas labyrinth that makes it difficult for gas to pass therethrough, determines the invasion of oil from the drive unit 40. It is possible to damp the pressure fluctuation from the operating portion applied to the oil seal portion on the drive portion side, and it is possible to effectively prevent the oil from entering the operating portions 20 and 30.

The dimension L1 of the intermediate chamber 51 in the rod axial direction is shorter than the stroke length S (L1 <
S), the partition wall portion 53a between the intermediate chamber 51a and the compression portion (operating portion) 22, and the intermediate chamber 51b.
Partition part 5 between the displacer part 30 and the displacer part 30
As the gas seal portion provided on each of 3b, a seal material of a type in which a backup material is urged by the rod 49 can be used. Even if the seal portion is worn and a clearance is generated between the rod 49 and the sealing property is deteriorated, the intermediate chamber 51 is shorter than the stroke length S and therefore adheres to the rod and enters the intermediate chamber 51. This is because the oil spreads, enters the clearance, the lubricity of the seal is maintained by the oil that has entered, the durability of the seal material can be improved, and the required sealing performance can be secured for a long time. However,
In this case, the oil used should be oil with a low vapor pressure that does not easily turn into oil vapor, and the oil that exists between the seal member and the rod in the gas seal section may become oil vapor and enter the operating section. Try to avoid it.

The above dimensions are set in consideration of the installation direction of the compression section 20 and the displacer section 30, the stroke length of the compression piston 21 and the displacer 31, the diameter and material of the rod 49, the sealing force of the sealing material 52, and the like. It is what is done.

In addition, in the one shown in FIG. 3, another embodiment is a sealing device 55B having a structure in which the gas is also stored in the voids but the number of the voids is not large, and the volume of the voids for the flowing gas is increased. According to the example, by allowing extra time for the gas to accumulate in the large voids, the pressure fluctuation transmitted from the operating parts 20, 30 to the intermediate chamber 51 side is absorbed, and the oil seal part 52 is provided. It is configured so that fluctuating pressure is not strong.

That is, the rod 49 is inserted and the rod 4
9. A sealing device 55B having a structure in which sealing pieces 83a and 83b which are slidably contacted with 9 are formed at both ends, and a large-capacity cylindrical cavity (space) 85 is held so as to surround the rod 49 between the sealing pieces 83a and 83b. Is.

If there is such a large-capacity cavity 85, the pressure fluctuations generated in the operating parts 20, 30 will also be caused by the large gap 8
5 is absorbed and transmitted to the intermediate chamber 51 side after being attenuated, it is possible to reduce the fluctuating pressure applied to the oil seal portion 52 on the drive portion side, and the oil enters from the drive portion 40 through the oil seal portion 52. Can be effectively prevented. Further, since the gas seal portion is a non-contact seal that does not come into contact with the rod, it is possible to obtain an advantage that a good seal can be maintained for a long time without deterioration of sealability due to wear, and in the oil seal portion 52, Even if there is a clearance between the rod 49 and the rod, the amount of oil that enters through the clearance can be limited to an amount that does not cause any practical problems, so that this type of oil seal device can also be applied, and the degree of freedom in design is expanded. The convenience and the like can be obtained in the same manner as in the previous embodiment.

By adopting the sealing device 55B having such a large volume for storing gas as described above, the drive unit 40 is
Therefore, it is possible to effectively prevent the oil from entering the operating portions 20 and 30.

Further, as shown in FIG. 4, the rod 49 is a partition portion 52D for inserting and supporting the rod 49 with a minute clearance P, and the wall length L5 of the partition portion 52D itself is long. I shall. Even if the clearance P has the clearance P as described above, if the clearance P has a long distance, the operating portion 2
Even for pressure fluctuations generated at 0 and 30, the clearance P over a long distance is a resistance to the transmission and is attenuated.
The fluctuating pressure applied to the oil seal portion 52 on the side is reduced,
From the drive unit 40 to the intermediate chamber 51 through the oil seal unit 52.
It is possible to prevent oil from getting into. As a result, it is possible to prevent oil from entering the operating portion from the drive portion.

Therefore, by adopting the seal device 55C having this long wall (partition) 52D structure, the amount of oil entering the intermediate chamber 51 from the drive unit 40 is reduced and the oil is moved to the operating unit 2.
It is possible to make sure that 0 and 30 do not enter.

Further, the sealing devices 55, 5 adopted
5B and 55C are all simple, and it is possible to realize a device with high sealing performance without increasing cost, which is very useful.

By the way, the one shown in FIG. 7 is an improvement of the gas compression / expansion device shown in FIG. 1. In the case of a device that uses a large amount of oil 46 enclosed in the drive section 40, for example, a cross guide space is used. A large 45 is provided to prevent a large amount of oil from adhering to the oil seal portion 52 and the partition wall portion 56, but this may increase the size of the drive unit and the size of the device. A gas compression / expansion device which is provided with a front chamber 71 between the drive unit 40 and the drive unit 40, and has a structure equivalent to that of taking a large cross guide space so that oil can be prevented from entering the intermediate chamber 51. The above-described gas seal device of the present invention can also be applied to this improved gas compression / expansion device. Next, a description will be given with respect to this, but since the configuration is almost the same as that of the gas compression / expansion device of FIG. 1, the description of the equivalent portions will be omitted and the different points will be described.

The compression section 20 side and the displacer section 30
On the side, between the intermediate chamber 51 and the cross guide space 45, there is a front chamber 71 (7 which has a predetermined length in the axial direction of the rod).
1a, 71b) are formed. The partition wall 73 (73a, 73a) between the front chamber 71 and the cross guide space 45 is formed.
b) is provided with an oil seal part 74 (74a, 74b),
In addition, a partition wall 61 (61
a, 61b) also has an oil seal part 75 (752a, 75b).
b) is provided.

When the front chambers 71a and 71b are provided in this way, the partition wall portion between the cross guide space serves as an obstruction wall for the oil that tries to enter from the drive unit 40 and prevents the oil from entering. The oil that has entered is stored in the front chamber 71 and is prevented from entering the intermediate chamber.

An oil return hole 78 for returning the oil that has entered and accumulated in the front chamber 71a to the oil reservoir 47 of the drive unit 40.
a is provided below the partition wall 73a, and an air hole 79a communicating with the cross guide space 45a is provided above the partition wall 73a.
The backflow of oil is prevented by balancing the pressures of 1a and the cross guide space 45a.

Similarly, on the displacer portion 30 side, oil seal portions 74b and 75b are provided on the partition wall 73b on the cross guide space 45b side of the front chamber 71b and the partition wall 61b on the intermediate chamber 51b side, respectively. An oil return hole 78b and an air hole 79b are provided in the.

By thus providing the front chamber 71 in the preceding stage of the intermediate chamber 51, the oil that has entered is accumulated in the front chamber 71, and the accumulated oil returns to the drive unit 40 from the oil return hole 78. In this way, since the invasion of oil can be suppressed, it is possible to use a non-contact seal, that is, a seal having a clearance, which does not urge the oil seal portion against the rod. Further, when the conditions are good, the partition wall between the front chamber and the cross guide space can be sufficiently prevented from entering oil even if the partition wall is thin. Thus, the amount of oil 46 fed by the reciprocating motion of the rod 49 can be reduced, and the life of the device can be extended.

Under the structure in which the front chamber 71 is provided,
The pressure fluctuations of the operating parts 20, 30 are caused by the oil seal parts 75, 7
As shown in FIG. 2, in the partition wall portion 53a on the compression section 20 side of the intermediate chamber 51a, a large number of rows of voids capable of attenuating the pressure fluctuation in the process where the same flowing gas as shown in FIG. The formed seal pieces form an oil seal device, that is, a labyrinth seal 58a, which exists between them and in which a gas maze is formed.

If the oil seal device having such a structure is provided on the side of the operating parts 20, 30 of the intermediate chamber 51, the pressure fluctuation generated at the operating part is transmitted in the process of propagating through many cavities of the oil sealing device. It receives resistance, is attenuated, and is connected to the intermediate chamber 51 and the front chamber 71. Therefore, the fluctuating pressure applied to the oil seal portion 75 between the intermediate chamber and the front chamber and the oil seal portion 74 at the boundary between the front chamber and the drive portion can be reduced. In this way, it is possible to prevent the oil seal portions 75, 74 from being affected by the fluctuating pressure from the operating portion as much as possible, so that it is possible to effectively prevent the oil that enters the operating portion from the drive portion through the intermediate chamber. it can.

Similarly, a labyrinth seal 58b having the same shape and structure is attached to the partition wall portion 53b between the displacer portion 30 and the intermediate chamber 51b. Accordingly, it is possible to prevent the fluctuating pressure from the displacer portion 30 side from being applied to the oil seal portions 75b and 74b sequentially arranged from the displacer portion 30 side of the gas.

In addition, it goes without saying that this gas seal device may be equipped with a gas seal device of the form shown in FIG. 3 or a gas seal device of the form shown in FIG.

Although the case where the sealing device is applied to a depressor type Stirling refrigerator has been described, the present invention is not limited to this, and an expansion piston type Stirling refrigerator, a Stirling engine and a reciprocating compressor. It may be used for the above.

[0082]

As described above, in the gas compression / expansion device in which the rod is reciprocated by inserting the partition into the partition for partitioning the driving part and the operating part, and the working gas is compressed / expanded by the piston at the rod end. In order to prevent oil from adhering to the rod from the drive part and entering the operating part, a cross guide space is provided to prevent the reciprocating cross guide from contacting the partition part. In addition to providing an intermediate chamber with a predetermined distance in the partition,
In addition, the partition wall between the intermediate chamber and the operating section provides a non-contact type seal device that acts as a passage resistance for the gas flowing between the two sections and can damp the pressure fluctuation from the operating section. It is possible to prevent fluctuating pressure from being applied to the oil seal on the part side and effectively prevent oil from entering the operating part.

Since the seal device for damping the pressure fluctuation from the operating portion is a non-contact seal having a clearance from the beginning with the rod, the conventional backup material has a drawback in that the rod is urged to wear. The sealing property does not deteriorate, and a long-life sealing device capable of maintaining a good seal for a long time can be provided. This also increases the reliability of the device.

Further, in order to suppress the gas flow, the above-mentioned sealing device has a simple structure which can be achieved by a void formed inside or a clearance having a long distance and can attenuate the pressure fluctuation. Since it is possible, the cost can be reduced.

Further, by adopting a structure including a large number of these voids or a labyrinth seal having a single void but having a large space capacity, an oil intrusion prevention structure can be obtained easily and at low cost. Therefore, the reliability of the device can be improved and the durability can be improved.

Furthermore, when the sealing device has a minute clearance with the rod, by using a sealing device having a structure in which the wall length of the sealing portion is long, the clearance is extended and the gas entry path is long. In this way, pressure fluctuations from the operating part are attenuated in a long transmission path and not transmitted to the oil seal part, which is simple in terms of equipment and has a high oil intrusion prevention effect. It will be the real benefit of.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a staring refrigerator including an oil seal device according to the present invention.

FIG. 2 is an enlarged configuration diagram of a gas sealing device shown in a portion A of FIG.

FIG. 3 is an enlarged configuration diagram of a gas sealing device according to another embodiment.

FIG. 4 is an enlarged configuration diagram of a gas sealing device according to still another embodiment.

FIG. 5 is a partial perspective view for explaining an oil return gap when the cross guide is set upright.

FIG. 6 is a diagram showing pressure fluctuations in an intermediate chamber, a working chamber, and a drive chamber that occur during operation of a staring refrigerator.

FIG. 7 is a configuration diagram when an oil seal device according to the present invention is provided in a staring refrigerator of another embodiment in which a front chamber is further added to the front stage of the intermediate chamber.

FIG. 8 is a conceptual configuration diagram of a gas compression / expansion device applied to the description of the related art.

FIG. 9 is a partial cross-sectional view for explaining the sealing effect of the sealing material.

[Explanation of symbols]

20 compression part (operating part) 21 piston 30 displacer part (operating part) 33 regenerator 40 drive part 42 (42a, 42b) cross guide 45 (45a, 45b) cross guide space 49 (49a, 49b) rod 50 (50a, 50b) Partition part 51 (51a, 51b) Intermediate chamber 53 (53a, 53b) Partition wall part 55 (55a, 55b), 55B, 55C, 58a, 5
8b Gas seal part 71 (71a, 71b) Front chamber 80, 83a, 83b Seal element 81, 85 Void P Clearance

Claims (4)

[Claims] 1. An operating part for accommodating a piston to which one end of a rod is connected so that the piston can reciprocate, and a drive mechanism for reciprocating a cross guide connected to the other end of the rod along the cross guide guide part. An oil seal device for a gas compression / expansion device having a drive section for inserting the rod and a partition section for partitioning the operating section and the drive section, wherein the cross guide reaches the partition point and the top dead center. An oil having a dimension between the cross guide space formed to be larger than the thickness of the oil attached to the cross guide and the oil collected in the cross guide space to an oil tank provided under the drive mechanism. A return means is provided inside the partition part including the rod, has a predetermined length in the axial direction of the rod, and has a rod radial dimension attached to the rod. The intermediate chamber formed larger than the thickness of the rod, the oil seal portion provided in the partition wall portion between the intermediate chamber and the cross guide space, and the rod in the partition wall portion between the operation portion side of the intermediate chamber. Is a non-contact seal having a structure which is provided with a clearance and is capable of attenuating the pressure fluctuation on the operating part side so as not to be transmitted to the intermediate chamber side and preventing the oil seal part from being subjected to a fluctuation pressure. An oil seal device for a gas compression / expansion machine, comprising: 2. The non-contact seal comprises a large number of ring-shaped seal pieces arranged in the rod axial direction, and a large number of continuous seal pieces formed between the seal pieces and arranged in the rod axial direction. Labyrinth seal having a space structure of a gas maze in which the gas flowing between the working part and the intermediate chamber is sequentially accumulated in the space part through the clearance between the tip of the seal piece and the peripheral surface of the rod. The oil seal device for a gas compressor / expander according to claim 1, wherein 3. The non-contact seal has a structure in which a pair of seal pieces that are separated from each other in the rod axial direction and face each other are provided, and a single gas reservoir space is formed between the seal pieces. An oil seal device for a gas compression / expansion machine according to claim 1, characterized in that. 4. An actuating portion for accommodating a piston to which one end of a rod is connected reciprocally, and a drive mechanism for reciprocating a cross guide connected to the other end of the rod along the cross guide guide portion. An oil seal device for a gas compression / expansion device, which has a drive part for operating the drive part and a partition part for partitioning the operating part and the drive part through which the rod is inserted,
The dimension between the partition and the cross guide reaching the top dead center is a cross guide space formed larger than the thickness of the oil attached to the cross guide, and the oil accumulated in the cross guide space is An oil returning means for returning to an oil tank provided in the lower part of the drive mechanism, and a rod provided inside the partitioning portion including the rod, having a predetermined length in the axial direction of the rod, and a radial dimension of the rod. Is an intermediate chamber formed to have a thickness larger than the thickness of the oil attached to the rod, an oil seal portion provided in a partition wall portion between the intermediate chamber and the cross guide space, and the operating portion side of the intermediate chamber. And a rod and a non-contact seal provided with a clearance, the non-contact seal having the seal wall length passing through the clearance to the operating portion side. Oil seal device for a gas compressor / expander, wherein the set to the gas flow transmitted into the intermediate chamber difficult to form a length such that the length of the clearance to dampen pressure fluctuations.