JPS5830110Y2 - Stirling engine lubricating oil sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a lubricating oil sealing device within a cylinder of a Stirling engine.

In a Stirling engine, intrusion of lubricating oil into the cylinder of the upper piston must be prevented because it significantly reduces the heat transfer efficiency of the engine.

Conventionally, the sliding method and the roll sock method, in which a roll sock made of a rubber-like material is attached to a stepped piston rod to seal the shaft, and excess lubricating oil accumulated under the roll sock is released using a pressure regulating valve, have been used. Although it has been adopted and has been somewhat effective, its mechanism has the drawback of being complex.

Therefore, the present invention provides a simple lubricating oil sealing device to replace the sliding method and roll sock method in Stirling engines.

That is, the present invention is a deformable elastic body whose upper end is fixed above the rod connecting the upper and lower pistons of a Stirling engine, and whose lower end is fixed to the inner wall of the cylinder located above the top dead center of the lower piston. The lubricating oil is sealed by a bellows frame consisting of a bellows frame, and a communicating hole is provided in a convex portion of a rod to which the upper end of the bellows frame is fixed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Fig. 1 is a side sectional view of the main part of a cylinder equipped with the lubricating oil sealing device of the present invention, Fig. 2 is a side sectional view showing the main part of another embodiment of the bellow flamm used in the present invention, and Fig. 3 is It is a side sectional view showing the principal part of another bellow frame similarly.

In Fig. 1, an upper piston 2 and a lower piston 3 are integrally attached by a rod 4 in a cylinder liner 1 of a Stirling engine, and the upper piston 2 is equipped with, for example, five fluororesin resin in order to seal the working gas. The piston ring 5 consisting of is fitted (・ru.

Similarly, two piston rings, for example, are fitted into the lower piston 3 as seal members.

Therefore, the upper end is attached to the convex portion 6 formed in the portion of the rod 4 that is fitted into the upper piston 2, and the lower end is attached to the inner recess 7 of the cylinder liner 1 located above the top dead center of the lower piston 3. The bellows 7 and the rams 10 each made of a deformable elastic body are fixed by a retaining ring 8°9, and a communicating hole 11 is provided in the protrusion 6, so that the external space A and the internal space B, which will be described later, are completely separated. is not blocked.

However, the space between the upper piston 2 and the lower piston 3 is partially divided into an external space A and an internal space B by the bellows flamm 10.

Therefore, the position of the recess 7, which is provided on the inner wall of the cylinder liner 1 and into which the lower part of the bellows frame 10 is fitted and fixed, is determined so that it does not come into contact with either the upper piston 2 or the lower piston 3 during operation of the Stirling engine. There is.

Therefore, by the integral vertical movement of the upper piston 2 and the lower piston 3, the bellows flamm 10 is
′, it deforms and follows.

Therefore, the external space A and the internal space B are almost completely separated, and the lubricating oil from the first crank side is completely blocked by the bellow frame 10, thereby almost completely preventing the lubricating oil from entering the external space A''-. I can do it.

Therefore, mixing of lubricating oil in the working gas can be completely prevented.
There is also no lubricant oil adhering to the fluororesin piston ring 5-.

What is important here is that the upper convex part 6 of the rod 4 is provided with a small communication hole 11, so that air can circulate between the inner space B and the outer space A through it, even though the passage is small, so that the upper and lower pistons With the vertical movement of 2 and 3, the internal space B
The air inside can enter and exit, and compared to the vertical movement of the piston in the sealed internal space B where the communication hole 11 is not provided, there is less air resistance due to the movement of air in and out, there is no power loss, and smooth vertical movement of the piston is possible. .

Of course, since the communicating hole 11 is located above the rod 4 and is a small hole, the intrusion of lubricating oil from the communicating hole 11 can be substantially ignored.

Further, since the communicating hole can utilize a convex portion for fixing the upper part of the bellows frame, it is easy to manufacture and no special equipment for the communicating hole is required.

Furthermore, there is no lubricant oil adhering to the walls of the heater, regenerator, cooler, etc. due to passage of the working gas, which causes a decrease in the heat transfer efficiency of the Stirling engine.

Therefore, the Stirling engine of the present invention has great effects in that the lubricating oil can be cut off and the vertical movement of the upper and lower pistons 2 and 3 can be made smoother.

Further, the bellow flammable 10 shown in FIGS. 2 and 3 is
The only difference in the mounting is the shape, and the other configurations are completely the same as in the previous embodiment.

Therefore, even if the bellows flamm 10 is installed as shown in FIGS. 2 and 3, the function of the lubricating oil sealing device of the present invention will not change in any way L'.

[Brief explanation of the drawing]

Fig. 1 is a sectional side view of the main part of a cylinder equipped with the lubricating oil sealing device of the present invention, Fig. 2 is a sectional side view of the main part of another bellows flamm embodiment, and Fig. 3 is a further embodiment of another bellows flamm. FIG. 1... Cylinder liner, 2... Upper piston, 3... Lower piston, 4...
Rod, 6... Convex portion, 10... Bellow frame, 11... Communication hole.

Claims (1)

[Scope of utility model registration request] A bellows frame made of a deformable elastic body whose upper end is fixed to the upper convex part of the rod that connects the upper and lower pistons of the Stirling engine, and whose lower end is fixed to the inner wall of the cylinder located above the top dead center of the lower piston. A lubricating oil sealing device for a Stirling engine, comprising: a communication hole provided in an upper convex portion of the rod to communicate a space divided by a bellows frame.