JPH11173692A - Gas compressor/expansion machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts, costs, and the size of a device by integrally forming a cross guide in a compression piston and a lower section of an expansion piston. SOLUTION: Between a compression section 20, an expansion section 30, and a drive section 40 is provided a guide member 49 equipped with cross guide holes 49a and 49b for stowing freely reciprocatingly a lower end section of a compression piston 21 and that of a lower section of an expansion piston 31. And, by sliding both sides of the lower end section of the compression piston 21 and that of the lower section of the expansion piston 31 over an inner wall of the cross guide holes 49a and 49b, a driving force from the drive section 40 is caused to be converted into a linear motion, thereby to reduce the number of members for conversion of linear motion and the size of a device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas compression / expansion machine in which a compression guide and an expansion piston are provided with a cross guide function for converting a driving force from a driving unit into a linear reciprocating motion.

[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. 6 shows a schematic configuration of such a gas compression / expansion machine.
1, an expansion section 130 with an expansion piston 131, and a drive section 14 with a crank mechanism 143.
0, having a cold storage unit 150 in which a cold storage material 151 is stored,
The cold storage section 150 is provided in the middle of a gas flow path 161 that connects the compression section 120 and the expansion section 130.

The compression section 120 includes a compression cylinder 122 for accommodating a compression piston 121, a compression space 123 provided on the head side of the compression cylinder 122, and a compression piston 121.
Buffer space 124 formed by the
The compression piston 121 includes a buffer chamber 125 communicating with the buffer space 124, a compression piston rod 126 for transmitting a driving force to the compression piston 121 through the partition 163, and the like. An oil seal 128 is provided on the rod 126.

The expansion section 130 includes an expansion cylinder 132 for accommodating an expansion piston 131, an expansion space 133 provided on the head side of the expansion cylinder 132, and an expansion piston 131.
Buffer space 134 formed by the
It has an expansion piston rod 136 and the like for transmitting a driving force to the expansion piston 131 through the buffer chamber 135 and the partition 163 communicating with the buffer space 134. The expansion piston 131 is provided with a gas seal 137 and an expansion piston. An oil seal 138 is provided on the rod 136.

The compression cylinder 122 is provided with radiation fins 164 to radiate the heat of the working gas generated by the compression to the outside.
A load 162 is mounted on the head side of the load 32.

The driving section 140 includes a crank mechanism 143 comprising cranks 142a and 142b fixed to a rotor 141 and a shaft 146, a storage tank 147 for storing oil for lubricating the crank mechanism 143 and the like, a crank mechanism 143, and a compression mechanism. Connecting rod 144a and cross guide 145 connected to piston rod 126
a, Crank mechanism 143 and expansion piston rod 136
A connecting rod 144b, a cross guide 145b, and the like, which are connected to the control rod.

In such a configuration, when the crank mechanism 143 rotates, the rotating power is reduced by the connecting rod 1.
It is transmitted to the compression piston 121 and the expansion piston 131 via 44a, 144b and the like.

At this time, the two cranks 142a, 142
b indicates that the shaft 146 moves so that the expansion piston 131 reciprocates with a phase approximately 90 degrees ahead of the compression piston 121.
It is fixed to.

While the compression piston 121 moves from the bottom dead center to the top dead center, the expansion piston 131 reaches the top dead center and moves downward. During this time, the working gas in the compression space 123 is adiabatically compressed and its temperature rises. However, heat is radiated to the atmosphere by radiation fins formed around the compression cylinder 122 and the like, and as a result, it can be regarded as isothermal compression.

The working gas in the compression chamber is supplied to the expansion piston 131.
The gas flow path 1 while exchanging heat in the regenerator 150 with the downward movement
61 flows to the expansion space 133 side, and the expansion piston 131 adiabatically expands as it approaches the bottom dead center, so that the temperature of the working gas decreases.

Then, the working gas whose temperature has dropped due to the upward movement of the expansion piston 131 flows through the gas passage 161 while cooling the load 162, exchanges heat in the regenerator 150, returns to the compression chamber, and performs one cycle. finish.

When the compression piston 121 and the expansion piston 131 reciprocate, the buffer chambers 124, 13
Space 4 acts to hinder the reciprocation,
The drive section 140 must drive the compression piston 121 and the like with a large force.

Therefore, the power supplied to the drive unit 140 increases, and the ratio of the amount of heat taken from the load 162 to the supplied power decreases. Since the lowering of the ratio becomes larger as the buffer spaces 124 and 134 become smaller, the buffer chambers 125 and 135 are conventionally provided separately.

[0015]

However, in the above configuration, the driving force from the crank mechanism 143 is transmitted to the compression piston 121 via the connecting rod 144a, the cross guide 145a, and the compression piston rod 126, and the driving rod 144b, Since the power is transmitted to the expansion piston 131 via the cross guide 145b and the expansion piston rod 136, the number of parts is increased, and there is a problem that the size of the apparatus is increased and the cost is increased.

Further, if the buffer chambers 125 and 135 are separately provided, there is a problem that the size of the apparatus is increased accordingly.

Accordingly, an object of the present invention is to provide a gas compression / expansion machine which solves the above-mentioned problems and enables downsizing and cost reduction.

[0018]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a driving unit having a crank chamber in which a crank mechanism is housed, and a driving unit receiving a driving force from the crank mechanism. The compression piston reciprocates and compresses the working gas in the compression space. The expansion piston receives reciprocating motion of approximately 90 degrees out of phase with the compression portion, and the expansion piston reciprocates. In a gas compression / expansion machine having an expansion section for expanding a working gas, a lower end portion of a compression piston and an expansion piston is provided between a compression section and an expansion section and a drive section or on the compression section and expansion section side of the drive section. And a guide member having a cross guide hole for reciprocally storing the guide member. By sliding the inner wall of the cross guide hole and the lower end side surface of the compression piston and the expansion piston, the driving force from the drive unit is converted into linear motion, thereby reducing the members for linear motion conversion. And miniaturization of the device.

According to a second aspect of the present invention, the back pressure side of the compression piston and the expansion piston integrally formed with the cross guide communicates with the crank chamber, and the crank chamber is used as a buffer space to reduce the size of the apparatus. Is characterized.

According to a third aspect of the present invention, there is provided an expansion piston having an expansion piston containing a regenerator material, an expansion piston connected to the expansion piston to expand a working gas, an expansion piston and an expansion piston. And a communication space formed between the compression section and the expansion section and communicating with a gas flow path that forms a flow path of the working gas between the compression section and the expansion section. And
The working gas flowing from the compression section into the communication space via the gas flow path passes through the upper portion of the expansion piston and flows into the expansion space while exchanging heat with the cold storage material. The expansion space is thereby expanded, whereby the working gas is expanded to obtain a low temperature.

According to a fourth aspect of the present invention, there is provided a compression cylinder in which a compression section accommodates a compression piston in a reciprocating manner, and a radiation fin disposed so as to cover the compression cylinder. Is formed so as to form a gas flow path, and the heat of the working gas flowing through the gas flow path is efficiently radiated.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows the gas compression /
FIG. 2 shows a cross-sectional view of the expander.

The gas compression / expansion device is provided with a crank 42
a drive unit 4 having a crank mechanism 43 composed of a and b
0, an expansion part 30 having an expansion piston upper part 39 and an expansion piston lower part 31, a compression part 2 having a compression piston 21
0 and so on.

The drive section 40 includes a rotor 41 for applying a rotational driving force to the crank mechanism 43, a storage tank 47 for storing oil for lubricating the crank mechanism 43, a crank 42a,
Connecting rods 44a, 44 connected to 42b
b etc.

The cranks 42a and 42b are fixed eccentrically to the shaft 46, and the phase of the compression piston 21 is delayed by about 90 degrees from the phase of the lower part 31 of the expansion piston.

The expansion section 30 includes an expansion piston lower part 31 and an expansion piston upper part 3 connected to the expansion piston lower part 31.
9, an expansion cylinder 32 (32a, 32) for reciprocatingly storing an expansion piston lower part 31 and an expansion piston upper part 39.
b), an expansion space 33 and the like provided on the head side (upper side in FIG. 1) of the expansion cylinder 32. The expansion cylinder 32 includes an expansion piston upper cylinder 32a in which an expansion piston upper part 39 reciprocates and an expansion piston 32a. The lower portion 31 is formed by a reciprocating expansion piston lower cylinder 32b.

A cold storage material 51 is accommodated in the upper portion 39 of the expansion piston, and a hole 39 communicating with the expansion space 33 is provided in the upper end surface thereof.
a is provided in large numbers. A load 62 is mounted on the head of the upper part of the expansion piston 39.

A communication space 39b for communicating the gas flow path G2 and the upper part of the expansion piston 39 is formed at the connection between the upper part 39 of the expansion piston and the lower part 31 of the expansion piston.

Accordingly, the working gas flows into the communication space 39b from the gas flow path G2, and exchanges heat with the cold storage material 51 to form the holes 39.
a flows into the expansion space 33, and conversely flows from the expansion space 33 to the gas flow path G2 through the expansion piston upper part 39.

Further, gas seals 37a and 37b are provided on the expansion piston upper portion 39 and the expansion piston lower portion 31 to increase the close contact between these gas seals and the expansion piston upper cylinder 32a and the expansion piston lower cylinder 32b.

An oil seal 38 is provided in the lower part of the expansion piston 31 to prevent oil from the drive unit 40 from entering the expansion unit 30.

The compression section 20 has a compression cylinder 22 for accommodating a compression piston 21, a compression space 23 provided on the head side of the compression cylinder 22, and the like.

A gas seal 27 is disposed on the compression piston 21 to bring the compression piston 21 and the compression cylinder 22 into close contact with each other.
8 is provided to prevent oil of the drive unit 40 from entering the compression unit 20.

Further, radiating fins 64 for dissipating the heat of the working gas to the outside are arranged around the compression cylinder 22 and the expansion piston lower cylinder 32b so as to cover them.

FIG. 2 is a sectional view taken along the line AA in FIG. 1 and shows a cylindrical gas flow path G1 formed between the radiation fin 64 and the compression cylinder 22, and the radiation fin 64 and the expansion piston lower cylinder 32b. A gas flow path G2 having a cylindrical shape is formed between the compression section 20 and the expansion section 30. The gas flow paths G1 and G2 are connected by a gas flow path G3.

The compression section 20 and the expansion section 30 are arranged side by side on the drive section 40 via the guide member 49, and
The guide member 49 is provided with cross guide holes 49a and 49b for reciprocally storing the lower ends of the compression piston 21 and the lower portion of the expansion piston 31.
By sliding the lower ends 9a and 49b and the lower end side surfaces of the compression piston 21 and the expansion piston lower part 31, the driving force from the driving unit is converted into linear motion.

In FIG. 1, the upper plate of the drive unit 40 also serves as the guide member 49, but it goes without saying that it may be provided separately from the upper plate of the drive unit 40.

The back pressure side of the compression piston 21 and the lower part of the expansion piston 31 is provided in communication with the crank chamber 45, and the large space of the crank chamber acts as a buffer space or a buffer chamber conventionally used. I have. Thereby, the number of parts and the size of the gas compression / expansion machine are reduced.

Although FIG. 1 shows the case where the radiation fin 64 is formed so as to surround the compression cylinder 22 and the expansion piston lower cylinder 32b, the present invention is not limited to this. For example, the radiation fins 65 may be formed so as to surround only the periphery of the compression cylinder 22 as shown in FIG. Of course, in this case, it is needless to say that a similar radiating fin may be provided around the expansion piston lower cylinder 32b.

By forming the radiation fins 65 so as to independently surround the periphery of the compression cylinder 22 and the like, the area of the radiation fins 65 can be increased, and the heat of the working gas is reduced by the heat of the working fins 65. Since the average distance of heat transfer can be reduced, heat can be efficiently dissipated. Therefore, when the gas compression / expansion machine is used in a refrigerator or the like, the coefficient of performance can be increased.

In the above description, the gas seals 27, 37
a, 37b and oil seals 28, 38 are compressed piston 2
1, the configuration fixed to the expansion piston lower part 31 and the expansion piston upper part 39 has been described. However, the present invention is not limited to this. For example, as shown in FIG. It may be configured to be fixed to the expansion piston lower cylinder 32b side.

Next, the operation of the gas compressor / expander based on the above configuration will be described with reference to FIG. As the crank mechanism 43 rotates, the rotating power is reduced by the connecting rod 4.
The compression piston 21 is transmitted to the compression piston 21 and the expansion piston lower part 31 via 4a, 44b, etc., and reciprocates with a phase delayed by about 90 degrees with respect to the expansion piston lower part 31. As described above, the expansion piston upper portion 39 is connected to the expansion piston lower portion 31.

As described above, since the driving force is transmitted to the connecting rods 44a and 44b via the crank mechanism 43, the connecting rods 44a and 44b do not reciprocate linearly. Therefore, conventionally, a cross guide is provided to convert the driving force from the connecting rods 44a, 44b into a linear reciprocating motion.

However, in the present invention, the compression piston 21 and the expansion piston lower part 31 are made of an aluminum alloy, phosphor bronze, stainless steel or the like from the viewpoint of lightness. Further, the compression cylinder 22 and the expansion piston lower cylinder 32b are formed of carbon steel, chromium molybdenum steel, stainless steel, or the like from the viewpoint of abrasion resistance and making the amount of thermal expansion substantially equal to that of the compression piston 21 and the like. . Further, the guide member 49 is made of phosphor bronze, cast iron,
It is formed by kelmet or the like.

As a result, the compression piston 21 and the lower part of the expansion piston 31 function as the original piston, and the cross guide holes 49a and 49b slide on the lower end side surfaces of the lower part of the compression piston 21 and the lower part of the expansion piston 31 to drive the drive unit. 4
The driving force from zero can be converted to linear motion to provide the function of a conventional cross guide.

Further, by providing the compression piston 21 and the expansion piston lower part 31 with the function of the cross guide in this way, the crank chamber 45 having a large space can be used as a buffer space and a buffer chamber.

Therefore, since a cross guide and a buffer space are not required, the number of parts can be reduced, and the size of the compression section 20 and the expansion section 30 can be reduced, and the cost and size of the gas compression / expansion machine can be reduced. Become like

When the compression piston 21 moves from the bottom dead center to the top dead center, the working gas in the compression space 23 is compressed. During this time, the lower part of the expansion piston 31 moves upward and reaches the top dead center, and then moves downward.

The working gas compressed by the upward movement of the compression piston 21 flows through the gas flow paths G1, G3, and G2 while being radiated by the radiation fins 64, and is sent to the expansion section 30.

When the lower part of the expansion piston 31 moves downward, the upper part 39 of the expansion piston moves downward together with the lower part of the expansion piston 31, so that the working gas flows into the upper part 39 of the expansion piston from the communication space 39 b and exchanges heat with the cold storage material 51. Hole 39
The liquid flows out of the expansion space 33 into the expansion space 33 (see FIG. 5A).

At this time, the volume of the expansion space 33 expands due to the downward movement of the expansion piston lower part 31, and the working gas expands, thereby lowering the temperature. That is, the load 62 can be cooled.

The pressure in the expansion space 33 and the pressure in the communication space 39b are only the pressure difference generated by the cold storage material 51, and the pressure difference is small, and the working gas flowing due to the pressure difference is always the cold storage material 51. Therefore, the working gas in the high-temperature communication space 39b does not directly flow into the working gas whose temperature has been lowered by expansion.

Thereafter, as the compression piston 21 approaches the bottom dead center, the expansion piston lower part 31 starts to move upward, and the working gas flows in the expansion piston upper part 39 and exchanges heat with the cold storage material 51. Returning to the compression space 23 via the gas flow paths G2, G3, and G1, the cycle ends (FIG. 5).
(B)).

[0054]

As described above, according to the first aspect of the present invention, the guide member having the cross guide holes for reciprocally receiving the lower ends of the compression piston and the expansion piston is driven by the compression unit and the expansion unit. Between the drive section and the compression section and the expansion section of the drive section, the inner wall of the cross guide hole slides on the side of the lower end of the compression piston and the expansion piston, so that the driving force from the drive section is increased. Can be converted to linear motion, and the cost can be reduced by reducing the number of members, and the compression unit and the expansion unit can be downsized, so that the gas compression / expansion machine can be downsized. .

According to the second aspect of the present invention, since the back pressure sides of the compression piston and the expansion piston communicate with the crank chamber, the crank chamber can be used as a buffer space. Is achieved.

According to the third aspect of the present invention, the expansion piston is constituted by the upper portion of the expansion piston, the lower portion of the expansion piston, and the communication space, and the working gas flowing into the communication space from the compression section via the gas flow path is provided. The heat exchange with the cold storage material allows the gas to flow into the expansion space through the upper part of the expansion piston, and the expansion space is expanded by the upper part and the lower part of the expansion piston. As a result, the working gas with a high temperature in the communication space flows between the upper part of the expansion piston and the upper cylinder of the expansion piston without exchanging heat with the cold storage material, while reducing the size of the gas compressor / expander. As a result, when the gas compression / expansion machine is used as a refrigerator, the refrigeration efficiency can be increased.

According to the fourth aspect of the present invention, the radiation fins are provided around the compression cylinder so as to cover the compression cylinder, and the gas flow path is formed between the radiation fin and the compression cylinder. The heat of the working gas flowing through the flow path can be efficiently radiated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a gas compression / expansion machine applied to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a sectional view of a gas compression / expansion machine instead of FIG. 1;

FIG. 4 is a sectional view of a gas compression / expansion machine instead of FIG.

FIG. 5 is a diagram showing a flow of a working gas in an expansion section.

FIG. 6 is a cross-sectional view of a gas compression / expansion machine applied to the description of the related art.

[Explanation of symbols]

 Reference Signs List 20 compression unit 21 compression piston 22 compression cylinder 23 compression space 27, 37a, 37b gas seal 28, 38 oil seal 30 expansion unit 31 expansion piston lower 32a expansion piston upper cylinder 32b expansion piston lower cylinder 33 expansion space 39 expansion piston upper 39a hole 39b Communication space 40 Drive unit 43 Crank mechanism 45 Crank chamber 49 Guide member 49a, 49b Cross guide hole 64, 65 Radiation fin G1, G2, G3 Gas flow path

Claims (4)

[Claims] A driving unit having a crank chamber in which a crank mechanism is housed; a compression unit compressing a working gas in a compression space by reciprocating a compression piston by receiving a driving force from the crank mechanism. , The phase of the compression unit is approximately 90
In a gas compression / expansion device having an expansion portion that expands a working gas in an expansion space by reciprocating an expansion piston in response to a driving force shifted by an angle, the compression portion and the expansion portion are connected to the drive portion. A guide member having a cross guide hole for reciprocally receiving the lower end portions of the compression piston and the expansion piston is provided between the compression unit and the expansion unit side of the driving unit, and an inner wall of the cross guide hole and the guide member. A gas compression / expansion machine wherein a driving force from the driving unit is converted into a linear motion by sliding a lower end side surface of a compression piston and an expansion piston. 2. The gas compression / expansion device according to claim 1, wherein a back pressure side of the compression piston and the expansion piston communicates with the crank chamber. 3. The expansion piston includes an upper portion of an expansion piston containing a cold storage material, a lower portion of the expansion piston connected to the upper portion of the expansion piston to expand a working gas, and a portion between the upper portion of the expansion piston and the lower portion of the expansion piston. And a communication space that communicates with a gas flow path that forms a working gas flow path between the compression section and the expansion section, and flows into the communication space from the compression section via the gas flow path. The working gas is
While exchanging heat with the cold storage material, the gas flows into the expansion space through the upper portion of the expansion piston, and the expansion gas is expanded by the upper portion of the expansion piston and the lower portion of the expansion piston to expand the working gas. The gas compression / expansion machine according to claim 1 or 2, wherein 4. The compression section has a compression cylinder for reciprocatingly accommodating the compression piston, and a radiation fin disposed to cover the compression cylinder, wherein a radiation fin is provided between the radiation fin and the compression cylinder. The gas compression / expansion machine according to any one of claims 1 to 3, wherein a gap formed in the gas flow path forms the gas flow path and radiates heat of the working gas flowing through the gas flow path.