JPH0754107B2 - Stirling engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for preventing a working gas sealed inside a Stirling engine having a reciprocating portion from leaking to the outside from the reciprocating portion. Related to the Stirling engine.

BACKGROUND ART A Stirling engine is generally filled with high-pressure working gas such as helium, and by heating and cooling this working gas with a heater and a cooler, expansion and contraction are caused to cause pressure fluctuations, and The output is taken out by the piston. However, if the working gas leaks to the outside, the engine output will decrease, and the lubricating oil in the crankcase, etc.
When it is carried to the heater side, it deteriorates due to heat and is deposited and deposited inside the device, which causes a problem of blocking the gas passage.

In order to solve the above-mentioned problems, as a conventional sealing device, a method of using carbon, Teflon, or those in which other materials are mixed as a material for a rod sealing ring is used. As another measure, there is a method of using a flexible plate such as a diaphragm or a bellows (for example,
Shoji Isshiki "Development of Stirling Engine", Industrial Research Committee, 82.7.25, P57, P194-196).

A typical example is a rolling seal shown in FIG. This is equipped with a rolling rolling diaphragm 3 made of rubber called a roll sock in a gap between the reciprocating rod 1 and the housing 2 to prevent the working gas in the working space 4 from flowing out to the crank chamber 5. Further, since the pressure of the working gas is high, the roll sock 3 is supported by the oil in the oil space 7 regulated by the pressure regulator 6. The oil that has flown into the crank chamber 5 by the pressure regulator 6 is returned to the oil space 7 by the oil pumping ring 8 as the rod 1 reciprocates.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, among the above-described conventional examples, those using a sealing ring are not sufficient to prevent gas leakage, and resistance loss at the seal portion is large and wear of the sealing ring, etc. There was a problem. On the other hand, in the configuration of the second conventional example using the bellows and the diaphragm, the amount of oil held in the oil space is unstable, and the device for adjusting the amount of oil becomes complicated, so that the oil shortage is further reduced. Since it is returned from the crankcase, the oil may be dirty or deteriorated, and the oil temperature may increase during operation.
Gas that dissolves in oil is generated, causing problems such as cavitation, which shortens the life of the sealing device.

In view of this, the present invention is intended to prevent contamination and deterioration of liquid such as oil and to supply a constant amount of liquid in the seal portion, and to keep the front-back pressure of the flexible plate substantially constant.

MEANS FOR SOLVING THE PROBLEMS The technical means of the present invention comprises a flexible partition plate such as at least two bellows or a diaphragm, a reciprocating member such as a piston rod, and a side wall such as a cylinder. A Stirling engine provided with a seal member between a reciprocating member and a side wall so as to enclose a liquid in a space formed by a partition plate and a side wall and divide the space for enclosing the liquid. It is provided.

Action The action of this technical means is as follows.

That is, since the liquid is sealed in the space formed by at least two bellows, the diaphragm and the side wall, there is almost no foreign matter mixed in or contaminated, and the liquid does not need to be the same as the lubricating oil, so that there is no flow loss. It is possible to select a liquid with a small amount of gas, or a liquid that hardly generates gas.Since the sealing device has a sealed structure even for a liquid that easily dissolves gas, problems such as cavitation due to gas generation during operation will occur if degassing occurs during liquid encapsulation. Absent. As a result, it is possible to obtain a sealing mechanism which has a long life and requires no maintenance.

Embodiment One embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 2, as the displacer 9 reciprocates, the working gas such as helium enclosed in the Stirling engine passes through the heater 10, the regenerator 11, and the cooler 12, and the high temperature space 13 and the low temperature space 14 are shown. Make a round trip between. On this occasion,
The working gas is heated and cooled by the heating device 10 and the cooling device 12 to repeat expansion and contraction. The pressure fluctuation caused thereby causes the power piston 15 to reciprocate to take out the output to the outside. In this example, the Stirling engine is applied to a heat pump, and the power piston 15 is connected to the compression piston 17 by the rod 16 and the space 18
Inhale and compress refrigerants such as CFCs. The sealing device is installed between the power piston 15 and the compression piston 17, and the diaphragms 20 and 21 are installed between the rod 16 and the side wall of the housing 19, and the diaphragms 20 and 21 and the side wall of the housing 19 are installed. A liquid such as oil is enclosed in the formed spaces 22 and 23. Further, between the spaces 22 and 23 in which the liquid is sealed, a pump 38 is provided as a liquid moving means, and a pressure resistant rod seal 24 which is in contact with the side wall of the rod 16 and the housing 19 is provided.

As a result, the working gas in the space 25 is separated by the diaphragm 20 from the space 22 containing the liquid supporting the diaphragm 20, and similarly, the refrigerant in the space 26 is the diaphragm 21 and the space containing the liquid supporting the diaphragm 21. Separated from 23.

When the pressures of the working gas in the space 25 and the refrigerant in the space 26 are different, the pressure of the liquid in the space 22 supporting the diaphragm 20 and the pressure of the liquid in the space 23 supporting the diaphragm 21 are also pressure. Make a difference. The pressure resistant rod seal 24 is provided to prevent the liquid in the spaces 22 and 23 from flowing into and out of the spaces due to this pressure difference. Further, by providing the pressure resistant rod seal 24, the liquid in the space 22 and the space
Since the liquid in 23 is pressure-separated, the pressure of the working gas in the space 25 and the pressure of the liquid in the space 22 can be almost the same, and the diaphragm 20 is not forced. . Similarly, the space 26 and the space 23 can be made to have almost the same pressure, and the diaphragm 21 is not subjected to excessive force. As a result, even if there is a pressure difference between the working gas in the space 25 and the refrigerant in the space 26, it is possible to seal without gas leakage. In addition, since the pump 38 is provided as the liquid moving means, for example, the liquid leaks from the liquid space 22 to the liquid space 23 through the gap between the pressure-resistant rod seal 24 and the rod 16, and the liquid in the liquid space 22 becomes insufficient. If the liquid level sensor (not shown) or the like detects the liquid amount, the pump 38 sends the liquid from the liquid space 23 to the liquid space 22 to constantly optimize the liquid amounts in the liquid spaces 22 and 23. Can be kept.

In this example, the diaphragm is installed between the rod and the side wall of the housing, but it goes without saying that it may be installed between the piston and the side wall of the housing. Although FIG. 2 shows an example of the free piston type Stirling engine, the seal device of the present invention using a general crankshaft or the like can be applied. Next, another embodiment of the present invention will be described. FIG. 1 shows a longitudinal sectional view of a main part of a Stirling engine of another embodiment. In this embodiment, double bellows 27 and 28 are used in place of the diaphragm to form the outer side of the double bellows. Bellows (hereinafter called external bellows)
Is attached to the side wall of the housing 29, and the other end is connected to one end of a bellows (hereinafter referred to as an inner bellows) that constitutes the inside of the double bellows, and the other end of the inner bellows is connected to the rod 30. Installed. Further, between the liquid spaces 31 and 32 in which the liquid is sealed, the rod 30 and the housing are
A pressure-resistant seal member 33 such as a motion O-ring that contacts the side wall of 29 is provided. With this configuration, when the piston 34 and the rod 30 reciprocate, the pressure of the working gas in the space 35 and the space
Pressure of liquid in 31 and pressure and space of refrigerant in space 36
The bellows 27 and 28 expand and contract so that the pressures of the liquids inside the 32 are substantially equal to each other. Further, in this example, the check valve 37 is provided as the liquid moving means. Check valve 37
By providing, when the liquid in one of the liquid spaces is insufficient and the bellows are in close contact, the liquid space side of the momentarily insufficient side becomes a negative pressure than the other liquid space side, and the liquid space side of the insufficient liquid side Flows in. As described above, when the liquid moving means such as the check valve and the pump is provided, a slight amount of liquid is allowed to leak from the seal member 33, so that the loss due to the sliding resistance of the seal member 33 can be reduced.

Although the inner bellows are shown shorter than the outer bellows in FIG. 1, they may have the same length or longer, and the double bellows may be multiple bellows such as triple or quadruple. Is of course.

Advantageous Effects of Invention The present invention can seal a liquid such as oil in a space having a pressure difference formed by at least two flexible partition plates such as bellows and side walls such as a housing in a Stirling engine, Since the liquid does not become dirty or deteriorated due to the liquid flowing out to the crank chamber, etc., it does not require maintenance, and since it has a structure that seals the liquid, it is a gas that has melted into the liquid when sealing the liquid. Can be defoamed, and defects such as cavitation due to gas generation due to temperature changes during operation can be prevented, so that the sealing device can be maintained for a long life. Further, since the liquid does not have to be the same as the lubricating oil, it is possible to freely select the most suitable liquid for the seal portion, such as a liquid with little flow loss and a liquid with almost no gas generation. Further, since a liquid moving means such as a check valve and a pump is provided, a slight amount of liquid can be leaked from the seal member, and the loss due to the sliding resistance of the seal member can be reduced.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a Stirling engine according to an embodiment of the present invention, FIG. 2 is a vertical sectional view of a main part of a Stirling engine according to another embodiment of the present invention, and FIG. 3 is a typical conventional example. It is a longitudinal cross-sectional view of a main part of a Stirling engine. 27,28 …… Double bellows, 29 …… Housing, 30 …… Rod, 31,32 …… Liquid space, 33 …… Pressure-proof sealing member, 3
4 ... piston, 35,36 ... space.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kinichi Adachi 1006, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) 39161 (JP, Y2)

Claims (3)

[Claims] 1. A reciprocating member, a seal member contacting the reciprocating member and a cylinder side wall forming a moving space of the reciprocating member, and reciprocating with the side wall positioned on both sides of the seal member. Two liquid spaces formed between the moving member, a flexible partition plate closing both sides of the liquid space, and a liquid moving means between the two liquid spaces,
A working gas space that is adjacent to one of the liquid spaces via the partition plate is provided, and is divided into a high temperature space and a low temperature space by a member that moves in the working gas space, and a superheater is provided on the high temperature space side. A Stirling engine that forms a bypass with a cooler in the low temperature space. 2. The Stirling engine according to claim 1, wherein the partition plate is a diaphragm or a multiple bellows. 3. The Stirling engine according to claim 1, wherein the liquid moving means is a pump or a check valve.