JP2823525B2 - Oil seal device for gas compression / expansion machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a gas compression / expansion system for compressing or expanding gas by reciprocating a piston.
The present invention relates to an oil seal device for an expander.

[0002]

2. Description of the Related Art As a mechanism for compressing or expanding a gas, a gas compression / expansion machine that reciprocates a piston in a cylinder as in a Stirling refrigerator, a Stirling engine, a reciprocating compressor and the like is known.
In such a cylinder-piston type gas compressor / expander, one end of a piston rod is connected to a piston and the other end is connected to a cross guide, and the piston is reciprocally housed in a piston working chamber which is a cylinder chamber. The cross guide is housed in a piston drive chamber in which a crank mechanism for driving the piston is provided. The piston drive chamber is provided with a crank mechanism for converting the rotation output of the drive motor into linear motion, and the connecting rod is connected to the cross guide.

[0003]

Usually, the gas compression /
The piston working chamber and the piston driving chamber of the expander are partitioned by a partition wall provided with an oil seal so that oil does not enter the piston working chamber from the piston driving chamber side.

However, when the cross guide reciprocates in the cross guide guide portion, the oil is pushed to the partition wall side by the cross guide or scatters on the partition wall, so that the piston rod is covered with the oil and gradually moves in the oil seal direction. And then into the piston working chamber.

In view of the foregoing, the present invention provides an oil seal device for a gas compression / expansion device which prevents oil from traveling along a piston rod from entering a piston working chamber into a piston working chamber. With the goal.

[0006]

According to a first aspect of the present invention, there is provided a piston working chamber in which a piston connected to one end of a piston rod is housed in a reciprocating manner, and a cross connected to the other end of the piston. In a gas compression / expansion machine sealing device in which a partition between a piston drive chamber and a drive mechanism for reciprocating a guide is disposed by a partition wall provided with a rod seal, a space between the partition wall and the cross guide is provided. Is formed larger than the outer shape of the cross guide, a plate having an outer shape larger than the outer shape of the cross guide is attached to the piston rod portion disposed in the space portion, and the space from the piston drive chamber to the partition wall is formed. It is characterized by preventing oil from entering.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, a passage for returning oil from a space between the partition wall and the cross guide to the piston driving chamber is formed. And

According to a third aspect of the present invention, in addition to the configuration of the first aspect, a space between the partition wall and the cross guide of the gas compression / expansion machine in which the piston rod is disposed horizontally. Is formed larger than the outer shape of the cross guide, and a plate having a lower outer shape than the outer shape of the cross guide is attached to the piston rod portion disposed in the space, and the partition wall is separated from the piston drive chamber. It is characterized in that oil is prevented from invading the air.

According to a fourth aspect of the present invention, in addition to the configuration according to the first aspect, a radiation fin is provided on an outer wall of a partition wall portion where the rod seal is provided.

[0010]

According to the first aspect of the present invention, since the plate member is provided between the cross guide and the rod seal, oil is prevented from traveling along the rod and accumulating near the rod seal, and the scattered oil is prevented. Can be prevented from adhering to the piston rod from the wall surface of the partition wall and approaching the vicinity of the rod seal, so that oil can be reliably prevented from entering the piston working chamber from the piston drive chamber.

According to the second aspect of the present invention, oil is returned to the piston driving chamber from the space between the partition wall and the cross guide, and the space is always kept in a clean state free of oil. In addition, it is possible to prevent oil from adhering to the piston rod and to more reliably prevent oil from entering.

According to the third aspect of the present invention, in the gas compressor / expander in which the piston rod is disposed horizontally,
Since the oil is scattered only in the lower portion, only the lower portion of the space between the partition wall and the cross guide is formed larger than the outer shape of the cross guide, and the space between the partition and the cross guide is formed in the piston rod portion disposed in the space portion. By attaching a plate whose lower side has an outer shape larger than the outer shape of the cross guide, processing and material costs can be saved.

According to the configuration of the fourth aspect, the rod seal is cooled by the radiation fins, deterioration is prevented, and desired sealing performance can be stably maintained for a long period of time.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, taking an example in which the present invention is applied to a Stirling refrigerator.

FIG. 1 is a schematic structural view of a Stirling refrigerator according to one embodiment of the present invention. The Stirling refrigerator has a compression space 2 of a gas compressor 1 and an expansion space 4 of a gas expander 3. , Are connected by a gas flow path 6 in which a regenerator 5 is interposed. Further, behind the gas compressor 1,
Further, below the gas expander 3, a crank chamber 9 in which a crank mechanism 8 for driving a piston is disposed is formed.

The gas compressor 1 compresses a refrigerant gas having a very low boiling point such as helium in accordance with a predetermined cycle, and supplies the compressed refrigerant gas to the expander 3. The compression piston 11 is fitted slidably in the compression cylinder 12, and the compression piston 11 is reciprocally driven by the operation of a crank mechanism 8 described later.

The expander 3 expands the compressed refrigerant gas supplied from the gas compressor 1 via the regenerator 5, and the gas expander 3 has an inner side of an expansion cylinder 13 disposed in a vertical direction. An expansion piston 15 with a piston ring 14 is vertically slidably fitted thereto, and a refrigeration generation section as an expansion space 4 where a low temperature is generated is formed inside the upper part of the expander 3.

The regenerator 5 is connected to the expander 3 via a gas passage 6.
While cooling the compressed refrigerant gas supplied to the gas compressor 1, the refrigerant gas expanded and cooled in the expansion space 4 is cooled and stored when the refrigerant gas is returned to the gas compressor 1. Copper and stainless steel with high specific heat,
Lead and the like are used, and they are formed in a cylindrical shape by forming a large number of fine holes through which a refrigerant gas passes.

The gas flow path 6 is a pipe for communicating the gas compressor 1 and the expander 3. At the inlet side of the regenerator 5 interposed in the middle, the compressed refrigerant gas passes through the regenerator 5 uniformly. Is configured.

The crank mechanism 8 reciprocates the compression piston 11 and the expansion piston 15 using a drive motor (not shown) as a drive source. This crank mechanism 8
A guide portion 17 for guiding the cross guide 16 behind the compressor 1 is formed in the crank chamber 9 for housing
Guide section 1 for guiding cross guide 18 below expander 3
9 are formed. A lubricating oil 20 is stored in the bottom of the crank chamber 9 and is supplied to each part of the crank mechanism 8.

One connecting rod 21 extending from the crank mechanism 8 is connected to a cross guide 16 slidably fitted on the guide portion 17. The other connecting rod 22 extending from the crank mechanism 8 is connected to a cross guide 18 slidably fitted on a guide portion 19 .

One end of the piston rod 25 is connected to the cross guide 16, and the other end is connected to the rear of the compression piston 11. The compression cylinder 12
The chamber and the crank chamber 9 are partitioned by a partition wall 27 having a rod seal 26.

Similarly, one end of the piston rod 28 is connected to the cross guide 18, and the other end is connected to the rear of the expansion piston 15. Further, a partition wall 30 having a rod seal 29 is partitioned between the expansion cylinder 13 and the crank chamber 9.

In order to prevent oil from penetrating the piston rod 25 into the rod seal 26 of the partition wall 27, the space 31 between the partition wall 27 and the cross guide 16 is defined by the outer dimensions of the cross guide 16. The piston rod 2 formed larger and disposed in the space portion 31
A disk-shaped plate member 32 having an outer shape larger than the outer size of the cross guide 16 is attached to five portions.

Similarly, the rod seal 2 of the partition 30
In order to prevent oil from penetrating through the piston rod 28 into the nine portions, a space 33 between the partition wall 30 and the cross guide 18 is formed to be larger than the outer dimensions of the cross guide 18, and the space 33 is formed in the space 33 . A disk-shaped plate member 34 having an outer shape larger than the outer size of the cross guide 18 is attached to the piston rod 28 provided.

The Stirling refrigerating machine of this embodiment is constructed as described above. When the crank mechanism 8 of the crank chamber 9 is driven by the rotation of a drive motor (not shown), the compression piston in the compression cylinder 12 of the gas compressor 1 is moved. 11 moves to the compression space 2 side, and hardly liquefied refrigerant gas such as helium or nitrogen filling the compression space 2 is compressed.

The compressed refrigerant gas flows into the regenerator 5 provided in the gas flow path 6. The refrigerant gas flowing into the regenerator 5 is cooled by a material having a large specific heat, for example, a regenerator made of a wire mesh or sphere of copper or lead, and the cooled refrigerant gas flows into the expansion space 4 of the expander 3 and has a high pressure. State.

Thereafter, the expansion piston 15 in the expansion cylinder 13 of the expander 3 descends with a phase difference of about 90 ° from the compression piston 11. As a result, the high-pressure refrigerant gas flowing into the refrigeration generator 4 from the regenerator 5 due to the expansion of the expansion space 4 is rapidly expanded, and the pressure of the refrigerant gas drops rapidly, so that the refrigerant gas has a low temperature.

Eventually, when the expansion piston 15 starts to rise and the compression piston 11 retreats, the low-temperature refrigerant gas passes through the regenerator 5 and returns to the compression space 2 via the gas flow path 6. At this time, in the regenerator 5, the regenerator material is cooled, and the regenerator 5 stores cold heat.

By the above-mentioned steps, one heat cycle is completed, and this step is repeated by the crank mechanism 8, whereby the temperature of the refrigeration generating section which is the expansion space 4 and the temperature of the regenerator 5 gradually decrease. The temperature of the refrigerant gas in the refrigeration generator becomes low, and the generated cold heat can be taken out and used.

Incidentally, in the Stirling refrigerator configured as described above, if oil is mixed with the refrigerant gas, the performance of the regenerator 5 is reduced, and the efficiency of refrigeration generation is reduced. To prevent this, the compression cylinder 12 chamber and the crank chamber 9
The partition wall 27 is provided with a rod seal 26 to prevent oil from entering the compression cylinder 12 from the crank chamber 9.
When the oil adheres to the rod seal 26, it accumulates in the vicinity of the rod seal 26 and eventually enters the compression cylinder 12 chamber. This is the same also between the expansion cylinder 13 chamber and the crank chamber 9.

Therefore, in order to prevent oil from coming along the piston rods 25, 28 near the rod seals 26, 29, in this embodiment, the space between the partition walls 27, 30 and the cross guides 16, 18 is provided. The portions 31, 33 are formed larger than the outer dimensions of the cross guides 16, 18, and the piston rods 25, 2 disposed in the space portions 31, 33 are formed.
Disk-shaped plate members 32 and 34 having external shapes larger than the external dimensions of the cross guides 16 and 18 are attached to the eight portions.

By doing so, the oil is prevented from traveling along the piston rods 25, 28 and accumulating near the rod seals 26, 29, and the scattered oil adheres to the piston rods 25, 28 from the wall surfaces of the partition walls. It is possible to prevent oil from entering the cylinders 12 and 13 from the crank chamber 9 by preventing the seals 26 and 29 from approaching the vicinity of the seals 26 and 29, and to keep the interior of the cylinders 12 and 13 oil-free at all times. it can.

FIG. 2 shows a sealing device for a gas compressor / expander according to another embodiment of the present invention, and only the side of the gas compressor 1 is shown in the figure. In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts, and the point different from the configuration in FIG.
The point is that an oil passage 40 for returning oil from 1 to the crank chamber 9 is provided.

As described above, by providing the oil return passage 40 for returning oil to the crank chamber 9 below the space portion 31, the space portion 31 can always be kept in a clean state free from oil. Oil is more reliably prevented from adhering to the rod portion between the plate member 32 and the rod seal 26 that is fixed to the rod seal 26, thereby preventing oil from entering the rod seal 26 portion. This oil return passage 4
If 0 is provided on the gas expander 3 side, it goes without saying that the same operation and effect can be obtained.

Incidentally, the plate material 32 fixed to the piston rod is not limited to a flat plate, and its shape can be appropriately designed, for example, by forming it into a conical shape as shown in FIG.

Also, as in the gas compressor 1 shown in FIG.
When the cylinder-piston is disposed in the horizontal direction, the splash of oil due to the reciprocating movement of the cross guide 16 is mainly at the lower part of the piston rod 25, and therefore, as shown in FIG. Instead, a space 311 between the cross guide 16 and the partition wall 27 is formed larger than the outer dimension of the cross guide 16 only in the lower portion, and only the lower portion of the cross guide 16 is formed in the piston rod 25 existing there corresponding to the space 311. Plate 32 larger than external dimensions
2 may be configured to be fixed.

FIG. 5 shows still another embodiment of the present invention, in which the same reference numerals as those in FIG. 1 denote the same parts. For example, as shown, the gas expander 3 side has a partition wall 30.
By forming the radiation fins 50 on the outer wall portion of
The temperature of the rod seal 29 can be suppressed by cooling the rod seal 29. As a result, deterioration of the rod seal 29 can be prevented, desired sealing performance can be maintained, and the life can be extended. The same applies to the gas compressor 1 side.

[0039]

According to the first aspect of the present invention, since the plate is provided between the cross guide and the rod seal, oil is prevented from traveling along the rod and accumulating near the rod seal. At the same time, it is possible to prevent the scattered oil from adhering to the piston rod from the partition wall surface and to approach the vicinity of the rod seal, thereby reliably preventing oil from entering the piston working chamber from the piston drive chamber. .

According to the second aspect of the present invention, oil is returned from the space between the partition wall and the cross guide to the piston drive chamber, and the space is always clean without oil. , The oil is prevented from adhering to the piston rod, and the intrusion of oil can be more reliably prevented.

According to the third aspect of the present invention, in the gas compression / expansion device in which the piston rod is disposed horizontally, the oil is scattered only in the lower portion, and therefore the partition wall and the cross The space between the guide and the guide is formed so that only the lower portion is larger than the outer shape of the cross guide, and a plate having a lower outer shape than the outer shape of the cross guide is attached to the piston rod portion disposed in the space portion. , Processing and material costs can be saved.

According to the structure of the fourth aspect of the present invention, the rod seal is cooled by the radiation fins, and is prevented from being deteriorated.
Desired sealing performance can be stably maintained for a long time.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of a Stirling refrigerator showing a first embodiment of the present invention.

FIG. 2 is a conceptual configuration diagram on the gas compressor side of a Stirling refrigerator showing a second embodiment of the present invention.

FIG. 3 is a conceptual configuration diagram on the gas compressor side of a Stirling refrigerator showing a third embodiment of the present invention.

FIG. 4 is a conceptual configuration diagram of a gas compressor side of a Stirling refrigerator showing a fourth embodiment of the present invention.

FIG. 5 is a conceptual configuration diagram of a Stirling refrigerator on a gas expander side according to a fifth embodiment of the present invention.

[Explanation of symbols]

12, 13 Cylinder 11, 15 Piston 16, 18 Cross guide 25, 28 Piston rod 26, 29 Rod seal 31, 33, 311 Space part 32, 34, 321, 322 Plate 40 Oil return passage 50 Radiation fin

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F25B 9/14 520 F25B 9/14 510

Claims (4)

(57) [Claims] 1. A piston working chamber in which a piston connected to one end of a piston rod is housed in a reciprocating manner,
Gas compression / gas separation between a piston drive chamber in which a drive mechanism for reciprocating a cross guide connected to the other end of the piston is disposed by a partition wall provided with a rod seal.
In the sealing device for an expander, a space between the partition wall and the cross guide is formed to be larger than the outer shape of the cross guide, and the piston rod portion disposed in the space portion is larger than the outer shape of the cross guide. An oil seal device for a gas compression / expansion machine, wherein a plate member having an outer shape is attached to prevent oil from entering the partition wall from the piston drive chamber. 2. An oil seal device for a gas compression / expansion machine according to claim 1, wherein a passage for returning oil from a space between said partition wall and said cross guide to said piston drive chamber is formed. 3. A lower portion of a space between the partition wall and the cross guide of the gas compression / expansion machine in which the piston rod is disposed horizontally is formed to be larger than the outer shape of the cross guide. 2. A plate member having an outer shape whose lower side is larger than the outer shape of the cross guide is attached to the arranged piston rod portion to prevent oil from entering the partition wall from the piston driving chamber. Oil seal device for gas compression / expansion machines. 4. The oil seal device for a gas compression / expansion machine according to claim 1, wherein a radiation fin is provided on an outer wall of a partition wall portion on which said rod seal is provided.