JPH09105561A - Stirling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high performance Stirling machine in which pressure loss of working gas on a gas flow passage between a compression space and an expansion space is reduced, and heat efficiency is increased. SOLUTION: An annular spacer 20 having an inclined upper surface is disposed in a gas inlet space 16 located at the bottom of an annular empty chamber 15 formed in the outer periphery of a second cylinder 12. With use of the spacer 20, inflow gas into the gas inlet space 16 smoothly horizontally diffuses, and flows through a heat regenerator 8 with less resistance upwardly of the annular empty chamber 15 as a uniform gas flow whereby an effective gas amount flowing into an expansion space is increased and hence terminal efficiency at the heat regenerator 8 is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling machine having improved performance by reducing pressure loss of a working gas in a gas flow path between a compression space and an expansion space.

[0002]

2. Description of the Related Art FIG. 9 is a schematic sectional view showing an example of a Stirling machine, where 1 is a first piston inserted in a first cylinder 11 and 2 is a second piston inserted in a second cylinder 12. A piston, 3 is a drive unit that reciprocates the first piston and the second piston with a certain phase difference, 4 is a gas compression space formed in front of the first piston 1, and 5 is in front of the second piston 2. The gas expansion space formed is shown.

Reference numeral 6 denotes a gas flow passage which connects the gas compression space 4 and the gas expansion space 5 to each other. In the gas flow passage 6, a gap type heat exchanger 7 is arranged on the gas compression space 4 side, while A heat regenerator 8 and a heat exchanger (radiation fin) 9 are provided on the expansion space 5 side.
And are arranged.

The second cylinder 12 is the inner cylinder 1
3 and the outer hollow cylinder 14, and the heat regenerator 8 is housed in an annular space 15 formed between the inner cylinder 13 and the outer hollow cylinder 14.

At the bottom of the annular space 15, the gas inlet space 1 into which the working gas from the gas passage 6 first flows.
6 are formed as a ring-shaped cavity and are continuously formed, and a gas inlet 17 is formed at one location on the bottom surface of the gas inlet space 16. Therefore, the working gas flowing from the gas inlet 17 rises from the gas inlet space 16, passes through the heat regenerator 8, and flows into the gas expansion space 5.

The gap type heat exchanger 7 provided on the first cylinder 11 side has a gap portion 19 provided between the outer peripheral wall of the inner cylinder of the cylinder and the inner peripheral wall of the outer cylinder having the heat radiation fins. Therefore, when the compressed working gas passes through the gap portion 19, heat is released to the outside. Reference numeral 10 denotes a flow path for adjusting back pressure in the rear space between the first piston 1 and the second piston 2.

With the above structure, first, when the drive unit 3 is driven, the first piston 1 moves to the gas compression space 4 side and the working gas such as helium and nitrogen which fills the gas compression space 4 and is difficult to liquefy is compressed. The compressed working gas is cooled by exchanging heat with the outside air in the gap type heat exchanger 7. Then, the working gas further flows into the heat regenerator 8 via the gas flow path 6. The working gas that has flowed into the heat regenerator 8 stores heat when passing through the filler inside, and the working gas flows into the gas expansion space 5.

After that, the second piston 2 in the gas expansion space 5
Comes down with a certain phase difference from the first piston 1.
As a result, the gas expansion space 5 is expanded and the heat regenerator 8 is expanded.
The high-pressure working gas that has flowed into the gas expansion space 5 rapidly expands, and the pressure of the working gas sharply drops, so that the working gas becomes a low temperature. Eventually, the second piston 2 starts to rise, and the first piston 2
When the piston 1 retracts, the working gas having a low temperature returns to the gas compression space 4 through the heat regenerator 8. At this time, cold heat is stored in the heat regenerator 8.

By the above-mentioned steps, one thermal cycle is completed, and this step is repeated by the reciprocating movement of the driving part, whereby the temperature around the gas expansion space is gradually lowered.

[0010]

By the way, the thermal efficiency of the heat regenerator increases as the amount of effective gas flowing from the gas compression space 4 of the first cylinder into the gas expansion space 5 of the second cylinder and acting on expansion increases. Will be things. Therefore, it is desirable that the working gas passes through the annular space 15 in which the heat regenerator 8 is disposed without any resistance difference, that is, without pressure loss, and passes through the heat regenerator 8 to uniformly flow the gas.

However, the conventional second cylinder 12 described above is used.
With this structure, the working gas enters the annular space through one gas inlet 17 which is close to one side in terms of position, the gas diffuses in the entire circumferential direction of the annular space, and then the space bottom surface and the vertical direction. Although the direction is changed so as to follow the inner surface of the annular space 15 and flows upward, when the distance from the gas inlet 17 decreases, the amount of gas reaching the area decreases, and when the gas changes direction at that location, the vertical inner surface of the annular space Since the angle between the bottom surface and the bottom surface is a right angle, the flow resistance becomes large for the gas, and the gas passing through the heat regenerator 8 becomes a weak gas flow, so that the total amount of gas flowing into the gas expansion space 5 is reduced and the thermal efficiency is reduced. There was a problem that was low.

The present invention has been made in view of the above problems, and provides a Stirling machine capable of smoothly flowing a working gas into a gas expansion space, increasing an effective gas amount, improving thermal efficiency, and enhancing performance. With the goal.

[0013]

In order to achieve the above object, a Stirling machine according to claim 1 of the present invention is provided with a first Stirling machine.
A gas compression space in front of the first piston in the cylinder and a gas expansion space in front of the second piston in the second cylinder communicate with each other through a gas flow path, and the first piston and the second piston reciprocate with a certain phase difference. First by driving
The compressed working gas that has flowed from the cylinder to the second cylinder is expanded and cooled, and the expanded working gas is returned to the first cylinder to repeat the heat cycle, and the outer hollow cylinder having the outer peripheral wall of the second cylinder and the heat radiation fins. In a Stirling machine in which cold heat is stored in a cylindrical heat regenerator housed in an annular space formed between and, in the annular space where the gas inlet from the gas flow path is open A gas in which the working gas that has flowed into the inner bottom is uniformly diffused in the entire peripheral region of the bottom of the annular cavity and flows into the gas expansion space as a uniform flow to the heat regenerator. A Stirling machine having an annular spacer for forming a flow.

According to a second aspect of the present invention, in the Stirling machine, the annular spacer disposed on the inner bottom of the annular space has a gas flow hole communicating with the gas inlet at one end or the gas. The end corresponding to the inflow port is formed in a cut-off shape, and is formed on the upper surface inclined at a constant angle so that the height gradually increases toward the end opposite to the gas inflow port.

Furthermore, in the Stirling machine according to a third aspect of the present invention, the annular spacer arranged on the inner bottom portion of the annular space is formed on a curved inclined upper surface that is recessed inward.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The same or equivalent components as those of the conventional device shown in FIG. 9 are designated by the same reference numerals.

Referring to FIG. 1, a second heat regenerator 8 is provided.
In the lower part of the annular vacant chamber 15 in the cylinder 12, that is, inside the gas inlet space shown in FIG. 16, an upper surface 21 having a ring shape as a whole and gradually increasing in height toward one side as shown in FIG. A spacer 20 having an obliquely cut shape is arranged. The spacer 20 is formed of a heat-resistant member such as a molded product of resin so as to withstand a high-temperature working gas, and a gas passage hole 22 is provided in the lower portion.

Therefore, the spacer 20 is arranged in the gas inlet space 16 with the gas passage hole 22 aligned with the gas inlet 17, and is firmly attached and fixed to the bottom of the gas inlet space 16 by an adhesive or the like. There is.

When such a spacer 20 is arranged in the bottom portion (gas inlet space 16) in the second cylinder 12 which is the gas inlet portion, the working gas from the gas flow path 6 passes from the gas inlet 17 to the gas flow hole 22. When passing through the gas inlet space 16, the gas flows along the inclined upper surface 21 of the spacer 20 without resistance, and the gas inlet space 1 on the opposite side of the gas flow hole 22 is provided.
It smoothly wraps around to the area 6 and diffuses sufficiently into the entire gas inlet space 16.

The gas that has flowed laterally (horizontally) in this way and then diffused into the gas inlet space 16 changes its direction from horizontal to vertical so as to rise along the inner surface of the second cylinder. At this time, the angle of the point where this flow changes
In the present invention, as shown in FIG. 4, since the obtuse angle β is formed between the inclined upper surface 21 of the spacer 20 and the inner side surface 24 of the second cylinder, a right angle is formed by the conventional horizontal cylinder bottom surface and the vertical inner surface. The resistance is reduced and the gas flow is improved, and the gas passes uniformly through the heat regenerator 8 without pressure loss, so that a sufficient amount of gas can be supplied to the gas expansion space 5 of the cylinder. Will be able to send. Therefore, the performance of the staring device is improved, and the thermal efficiency of the heat regenerator 8 can be improved.

Further, when the spacer 20B formed on the upper surface of the spacer on the inclined upper surface 21b curved inward (downward) so as to draw a downward convex curve as shown in FIG. 5 is used, the resistance against gas flow is further reduced. Therefore, it becomes possible to promote the diffusion and rise of gas more effectively, and it becomes more effective by improving the thermal efficiency. Further, it goes without saying that the maximum output can be obtained by appropriately setting the degree of curvature in association with structural elements such as the inner diameter of the cylinder and the driving force of the piston.

FIGS. 6 to 8 show a spacer 20C according to another embodiment, which is different from the spacer 20 of the first embodiment in that a gas passage hole 22 for introducing gas is not provided, but a gas passage. 6, the end 2 on the side corresponding to the gas inlet 17
6 is a spacer 20C having a shape in which 6 is widely cut.

In this spacer 20C, the gas can be introduced by cutting off the end portion 26, and it is not necessary to form the gas circulation hole 22 unlike the spacer 20 of the first embodiment, so that the processing is facilitated and the cost is reduced. It can be cheap.

[0024]

As described above, according to the first aspect of the present invention,
In the annular space around the cylinder where the tubular heat regenerator is placed,
Since the working gas flowing from the unevenly located gas inlets is sufficiently guided to the side far from the gas inlets, and the spacer is arranged so as to form a gas flow that uniformly flows into the working space of the cylinder, the spacer is arranged. Even in the heat regenerator, which is concerned that the flow rate will decrease due to resistance, the gas passes through as a uniform flow, the amount of effective gas sent to the gas working space is sufficient, and the heat storage degree in the heat regenerator is also increased. It is possible to provide a staring device that can improve thermal efficiency.

Further, specifically, as in the second aspect of the invention, the spacer is annular and has an inclined upper surface, so that the gas flow can be easily and uniformly flown, and also in terms of constitution. It is not complicated and can be realized at low cost.

Further, if the inclined upper surface of the spacer is curved inwardly, a more uniform gas flow can be formed, and it is possible to provide a staring machine with further improved thermal efficiency and performance. become.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a staring machine according to the present invention.

FIG. 2 is a perspective view of a spacer for forming a gas flow that evenly flows in the heat regenerator of the present invention.

FIG. 3 is a vertical sectional side view of the spacer.

FIG. 4 is a plan view of the spacer.

FIG. 5 is a side view of a spacer according to another embodiment in which an upper surface has an inclined surface curved downward.

FIG. 6 is a perspective view of a spacer according to another embodiment.

FIG. 7 is a vertical sectional side view of the spacer.

FIG. 8 is a plan view of the spacer.

FIG. 9 is a schematic sectional view of a conventional staring machine.

[Explanation of symbols]

 1 1st piston 2 2nd piston 6 Gas flow path 8 Heat regenerator 12 2nd cylinder 15 Annular space 16 Gas inlet space 17 Gas inlet 20, 20B, 20C Spacer

Claims (3)

[Claims] 1. A gas compression space in front of the first piston in the first cylinder and a gas expansion space in front of the second piston in the second cylinder communicate with each other through a gas flow path, and the first piston and the second piston are provided. By reciprocatingly driving with a phase difference, the compressed working gas flowing from the first cylinder into the second cylinder is expanded and cooled, and the thermal cycle in which the expanded working gas returns to the first cylinder is repeated, In a Stirling machine in which cold heat is stored in a cylindrical heat regenerator housed in an annular space formed between an outer peripheral wall of a second cylinder and an outer hollow cylinder having a heat radiation fin, The working gas that has flowed into the inner bottom portion of the annular cavity where the gas inlet is open diffuses uniformly throughout the entire bottom area of the annular cavity and rises to the heat regenerator as a uniform flow. Pass through Stirling devices, characterized in that arranged annular spacers to form a gas stream so as to flow into the serial gas expansion space. 2. The annular spacer disposed on the inner bottom portion of the annular space has a gas flow hole communicating with the gas inlet port at one end or an end portion corresponding to the gas inlet port is cut off. The said upper surface is formed in a gradual shape, and is formed on an upper surface inclined at a constant angle whose height gradually increases toward the end opposite to the gas inlet.
Stirling equipment as described. 3. The Stirling machine according to claim 2, wherein the annular spacer disposed on the inner bottom portion of the annular space is formed on a curved inclined upper surface that is recessed inward.