JP2877733B2 - Gas compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder-piston type gas compressor for compressing gas by reciprocating a piston in a cylinder.

[0002]

2. Description of the Related Art A cylinder-piston type gas compressor is
It is used in various devices such as a Stirling engine and a reciprocating compressor. In a Stirling refrigerator, it is used to send compressed gas to a gas expander to expand the gas and extract refrigeration heat.

FIG. 4 shows a conventional example of a Stirling refrigerator using such a gas compressor. The Stirling refrigerator has a compression space 2 of a gas compressor 1 and an expansion space 4 of a gas expander 3. To a gas flow path 6 with a regenerator 5 interposed
Are linked by Further, a crank chamber 9 in which a crank mechanism 8 for driving a piston is provided behind the gas compressor 1 and below the gas expander 3.

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.

[0005] The expander 3 expands the compressed refrigerant gas supplied from the gas compressor 1 via the regenerator 5. In the gas expander 3, the inside of an expansion cylinder 13 provided in the vertical direction is provided. 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.

[0006] 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 the guide portion 17.

[0008] 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 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. The expansion cylinder 13 chamber and the crank chamber 9 are partitioned by a partition wall having a rod seal 29.

In the above configuration, when the crank mechanism 8 of the crank chamber 9 is driven by the rotation of a drive motor (not shown), the compression piston 11 in the compression cylinder 12 of the gas compressor 1 moves to the compression space 2 side to compress. The hardly liquefied refrigerant gas such as helium or nitrogen filling the space 2 is compressed.

The compressed refrigerant gas flows into the regenerator 5 provided in the gas passage 6. The refrigerant gas flowing into the regenerator 5 is cooled by a material having a large specific heat, for example, a regenerator material formed 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 that has expanded into the expansion space 4 from the regenerator 5 and expanded into the expansion space 4 is rapidly expanded, and the pressure of the refrigerant gas drops sharply, so that the refrigerant gas has a low temperature.

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-described 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.

[0015]

By the way, in the Stirling refrigerator configured as described above, when the refrigerant gas is compressed in the compression space 2 on the gas compressor 1 side, heat is generated and the refrigerant gas is heated to a high temperature. become. If this high-temperature gas flows through the regenerator 5 in the gas flow path 6 as it is, the cooling efficiency is reduced. Conventionally, on the compressor 1 side, a gap 31 through which the compressed gas passes is formed along the outer wall of the cylinder 12 having the radiation fins 30 and the inner wall of the cylinder 12 and connected to the gas flow path 6, Cooling the refrigerant gas flowing into the air.

However, in the structure of the above-mentioned conventional compression cylinder, since the gas passage is formed inside the cylinder, the cylinder 12 block with the radiation fins 30 becomes large, and the whole gas compressor becomes large. In addition, there is a problem that the volume of the cylinder-piston portion is reduced.

Therefore, the present invention solves the above problems,
It is an object of the present invention to provide a gas compressor that can reduce the size of the entire gas compressor or increase the internal volume of a piston portion including a gas compression space.

[0018]

According to a first aspect of the present invention, there is provided a gas compressor for causing a piston to reciprocate in a front-rear direction in a cylinder to flow gas from the outside into a compression space in front of the piston, compress the gas, and discharge the gas. A gas flow gap is provided between the inner wall of the cylinder and the outer peripheral surface of the piston facing the inner wall of the cylinder, and the rear end of the outer peripheral surface of the piston slides against the inner wall of the cylinder to allow gas to flow backward of the piston. A piston ring for preventing gas from flowing out of the gap from the piston ring position at the top dead center where the piston moves in the direction of the gas compression space toward the gas compression space. I do.

A second aspect of the present invention is characterized in that a radiation fin is formed on the outer peripheral surface of the cylinder in addition to the configuration of the first aspect.

According to a third aspect of the present invention, in addition to the configuration according to the first aspect, a cylinder communicating with the inside of the piston is provided on the front surface of the piston, and the cylinder is slidably mounted on the cylinder. A ring for blocking communication between the inside of the piston and the compression space is mounted on the outer peripheral surface of the cylindrical body while forming a guide portion for holding.

[0021]

According to the first aspect of the present invention, the compressed gas is caused to flow out to the outside through the gap formed between the inner wall of the cylinder and the outer peripheral surface of the piston. There is no need to form a gas flow path in the inside, and the cylinder thickness can be reduced. As a result, the configuration of the entire gas compressor can be made compact. Alternatively, the compression space can be enlarged with the same volume configuration as in the related art, and the compression work efficiency can be increased.

According to the second aspect of the present invention, by forming the radiation fins on the outer peripheral surface of the cylinder, the compressed gas can be efficiently cooled and discharged to the outside.

According to the third aspect of the present invention, the piston is slidably held by the ring portions provided on the front and rear portions, so that a stable reciprocating operation can be performed without performing cantilever drive. Become.

[0024]

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 configuration diagram of a Stirling refrigerator according to one embodiment of the present invention, and FIG. 2 is an enlarged view of a gas compressor portion of the Stirling refrigerator. In the figure, the same reference numerals as those in FIG.
The difference from the configuration of the first embodiment is that the inner wall of the cylinder 40 and the piston 1
A gap 41 through which gas flows is provided between the outer peripheral surface of the piston (hereinafter, abbreviated as an outer wall of the piston 11) facing the inner wall of the first cylinder 40 and the piston at the top dead center where the piston 11 moves in the gas compression space 2 direction. Ring 10
The point is that a gas passage 42 is formed on the gas compression space 2 side from the position to allow gas to flow out of the gap 41 to the outside. Also,
The radiating fin 43 is formed directly on the outer peripheral surface of the cylinder 40.

As described above, by providing the gas flow gap 41 between the inner wall of the cylinder 40 and the outer wall of the piston 11 so as to allow the gas to flow out, a gas passage is formed in the cylinder wall as in the related art. This eliminates the necessity and makes it possible to reduce the thickness of the cylinder portion. Alternatively, when the external dimensions are not changed, the piston diameter can be set large to increase the volume of the compression space 2, and the volume of gas to be compressed can be increased to increase the compression work.

Further, since the radiation fins 43 are formed on the outer peripheral surface of the cylinder 40, the gas taken out to the outside is cooled by the cylinder 40 on which the radiation fins 43 are formed when flowing through the gap 41. As a result, the compressed gas flows into the cooler 5 provided in the gas flow path 6 in a considerably cooled state, and the cooling efficiency of the cooler 5 is increased, so that the compressed gas having a lower temperature is supplied to the gas expander 3 side. As a result, lower-temperature refrigeration heat can be generated.

FIG. 3 is a schematic structural view of a gas compressor portion of a Stirling refrigerator according to another embodiment of the present invention. 2, the same reference numerals as those in FIG. 2 denote the same or corresponding parts, and the difference from the configuration in FIG. 2 is that a cylinder 50 communicating with the inside of the piston 11 is formed Is formed slidably, while the piston 1 is provided on the outer peripheral surface of the cylindrical body 50.
A ring 52 for blocking communication between the inside of the compression space 1 and the compression space 2
It is the point that was attached.

With such a configuration of the gas compressor, the piston 11 is provided with the guide portion 5 formed at the cylinder inner wall portion 53 behind the gas passage 42 and the cylinder tip portion.
As a result, the piston 11 is not driven in a cantilever manner, but is stably supported at both ends of the piston, and a stable reciprocating operation is performed.

At this time, the guide portion 51, the cylindrical body 52, and the inside of the piston 11 communicate with each other to increase the volume, thereby reducing the resistance when the piston 11 reciprocates. In this case, the guide portion 51 may be connected to the buffer tank to further reduce the resistance when the piston 11 reciprocates. The same applies to the space behind the piston. By connecting the space behind the piston to the buffer tank, loss other than work in the compression space 2 can be reduced.

[0031]

According to the first aspect of the present invention, the compressed gas is caused to flow out to the outside through the gap formed between the inner wall of the cylinder and the outer peripheral surface of the piston. There is no need to form a gas flow path in a cylinder as in the conventional case, and the thickness of the cylinder can be reduced. As a result, the configuration of the entire gas compressor can be made compact. Alternatively, the compression space can be enlarged with the same volume configuration as in the related art, and the compression work efficiency can be increased.

According to the configuration of the second aspect of the present invention, by forming the radiation fins on the outer peripheral surface of the cylinder, the compressed gas can be efficiently cooled and discharged to the outside.

According to the configuration of the third aspect of the present invention, the piston is slidably held by the ring portions provided at the front and rear portions, so that a stable reciprocating operation can be performed without being cantilevered. You will be

[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 an enlarged view of a gas compressor portion of the Stirling refrigerator shown in FIG.

FIG. 3 is a conceptual configuration diagram of a gas compressor part of a Stirling refrigerator showing a second embodiment of the present invention.

FIG. 4 is a conceptual configuration diagram of a conventional Stirling refrigerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas compressor 2 Compression space 10 Piston ring 11 Piston 40 Cylinder 41 Gap 42 Gas passage 43 Heat radiation fin 50 Cylindrical body 51 Guide part 52 Ring

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

Claims (3)

(57) [Claims] 1. A gas compressor in which gas flows from the outside into a compression space in front of a piston by a piston which reciprocates in a cylinder in a front-rear direction, and is compressed and discharged. A piston inside the cylinder and a piston opposed to the cylinder inner wall A gas flow gap is provided between the piston and the outer peripheral surface, and a piston ring is disposed on the rear end side of the outer peripheral surface of the piston so as to slidably contact the cylinder inner wall and prevent gas from flowing out to the rear of the piston. A gas compressor characterized in that a gas passage is formed on a gas compression space side of a piston ring position at a top dead center moving in a gas compression space direction to flow gas out of the gap to the outside. 2. The gas compressor according to claim 1, wherein radiation fins are formed on an outer peripheral surface of said cylinder. 3. A cylindrical body communicating with the inside of the piston is provided on the front surface of the piston, and a guide portion for slidably holding the cylindrical body is formed in the cylinder, while the piston is formed on an outer peripheral surface of the cylindrical body. 2. The gas compressor according to claim 1, further comprising a ring for blocking communication between the inside and the compression space.