JPS60212660A - Stirling engine - Google Patents

Abstract

PURPOSE:To reduce the friction loss associated with sliding thus to improve the efficiency of engine by securing a bearing through bearing housing to the inner wall of cylinder and supporting the outercircumferential face of power piston rod slidably through said bearing. CONSTITUTION:The outer ring of linear roll bearing 31 is secured to the inside of bearing housing 32 secured to the inside of cylinder 20 to fit and support the power piston rod 22 reciprocally by means of said bearing 31. While the outer ring of linear roll bearing 33 is secured to the inside of the rod 22 to fit and support the displacer piston rod 17 reciprocally. Since the sideface force associated with the load functioning onto the power piston 18 conventionally received by cross head is now received by the bearing 31, the frictional factor can be reduced considerably resulting in considerable reduction of frictional loss caused by the sideface force.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a Stirling engine, and more particularly to an improvement of the crosshead portion of the Stirling engine for higher efficiency and quieter operation.

[Prior art]

An example of a typical structure of a conventional Stirling engine power transmission mechanism is shown in FIG. In the figure, ■ is the crankcase, and all parts of the Stirling engine are assembled and configured based on this part. 2
is a flange that is fixed with a fastening part such as a bolt into a hole machined in the crankcase; 3 is a bearing housing that is fastened and fixed to the crankcase 1 in the same way as flange 2; 4 is a flange that is fastened and fixed to the crankcase 1; 5 is a bearing fixed to the bearing housing 3, and 6 is a bearing fixed to the flange 2. A crankshaft 7 is rotatably held by a bearing 5.6 and transmits the power generated by the Stirling engine to the outside. Reference numeral 8 denotes a mechanical seal attached to the crankshaft 7 for sealing off the gas sealed within the crankcase 1.

9.10 is a balance weight for balancing the rotation of the crankshaft 7 of the Stirling engine;
is fixed.

Reference numeral 14 denotes lubricating oil collected at the bottom of the crankcase 1 for lubricating the moving parts of the Stirling engine.

Reference numeral 15 denotes a splasher for splash lubrication, which is usually attached to a connecting rod for a displacer or a connecting rod for a power piston.

11.12 is a power piston connecting rod connected to the crankshaft 7 by a bearing, and 21 is a crosshead connected to the power piston connecting rod 11.12. A power piston rod 22 and a power piston 18 are fixedly connected to this crosshead 21 . Further, the outer periphery of the crosshead 21 is fitted to the inner periphery of the cylinder 20 so as to be able to slide back and forth with a bearing function.

Reference numeral 13 denotes a displacer connecting rod, which is rotatably connected to the crankshaft 7 by a bearing. 16 is a piston pin, 17 is a displacer piston rod, and 19 is a displacer piston. The displacer piston rod 17 is connected to the displacer connecting rod 13 by the piston pin 16. The displacer piston rod 17 is connected to the crosshead 21. Power piston rod 22. It passes through the center of the circular cross section of the power piston 18 and is fixedly connected to the displacer piston 19.

20 is a cylinder portion fixed to the upper part of the crankcase 1, and inside this cylinder 20, a displacer piston 19. The power piston 18 is designed to slide back and forth.

Note that the explanation of structural parts such as the combustor section and the heat exchanger section of the Stirling engine will be omitted.

Next, the operation will be explained.

In the so-called one-cylinder, two-piston series-arranged crankshaft Stirling engine as shown in FIG. 1, pressure fluctuations generated within the cylinder 20 (pressure generation mechanism is omitted) act on the power piston 18 This is converted into force and the power piston rod 22. cross head 21
．． The power is transmitted to the connecting rod 11.12 for the piston. The rotational work is then taken out from the crankshaft 7.

A portion of the rotational work is transmitted to the displacer piston 19, inducing reciprocating motion and causing it to operate as a Stirling engine.

In this way, in the conventional Stirling engine,
The axial force of the power piston 18 acts on the crosshead 21, but as is well known, lateral force is generated on the cylindrical side surface of the crosshead 21 and the inner wall of the cylinder 20, and this lateral force can be extracted as rotational work. This is something that cannot be done. Therefore, this side force is consumed as friction loss on the outer peripheral sliding surface of the crosshead 21, resulting in a disadvantage that the efficiency of the Stirling engine is reduced. That is, normally the crosshead 21. The coefficient of friction between the cylinders 20 is large, ranging from 0.1 to 0.2, which increases the friction loss in this portion.

Another drawback is that the conventional crosshead 21 is large and performs large reciprocating movements, which causes vibration and noise in the Stirling engine due to reciprocating inertia, which interferes with quiet operation. It had become.

[Summary of the invention]

The present invention has been made in view of the above problems, and a bearing is fixed to the inner wall of the cylinder via a bearing housing, and the outer circumferential surface of a power piston rod is supported by the bearing so as to be slidable in a reciprocating manner. The present invention aims to provide a Stirling engine that can reduce the friction loss associated with motion, reduce the size of the conventional crosshead equivalent part, reduce vibration and noise, and achieve high efficiency and quiet operation. The purpose is

[Embodiments of the invention]

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

FIG. 2 is a diagram showing the basic structure of a Stirling engine according to an embodiment of the present invention. Power piston 18. Displacer piston rod 17° Power piston rod 22. Displacer connecting rod 13. The construction of the connecting rods 11, 12 for the power pistons is basically the same type as the conventional ones. In this embodiment, cylinder 2
An outer ring of a linear rolling bearing 31 is fixed further inside a bearing housing 32 fixed to the inside of the bearing housing 32, and the rolling bearing 31 fits and supports the power piston rod 22 so as to be able to reciprocate.

Further, an outer ring of a linear rolling bearing 33 is fixed to the inside of the power piston rod 22, and thereby the displacer piston rod 17 is fitted and supported so as to be able to reciprocate and slide.

Furthermore, the connecting rod connector 3 is the part that connects the two power pistons 11 and 12, which corresponds to the conventional crosshead.
It is 4. This connecting rod connector 34 differs from a conventional crosshead in that its outer peripheral portion does not need to be in contact with the inner surface of the cylinder 20, and naturally does not perform a bearing action. Therefore, the outer diameter and height of the connecting rod connector 34 can be reduced.

In this embodiment of the device, the side force associated with the load acting on the power piston 18, which was conventionally received by the crosshead, is absorbed by the linear rolling bearing 31 whose friction coefficient is usually 0.005 to 0.015. I decided to receive it with
This is much smaller than the conventional friction coefficient of 0.1 to 0.2, and the friction loss due to the side force can be significantly reduced.

Furthermore, conventionally, in order to receive the side force as described above, the outer circumferential surface of the cross head 21 is fitted in contact with the inner circumferential surface of the cylinder 20 so as to be able to reciprocate. Although the outer diameter was set large,
In the device of this embodiment, since there is no need to slide the outer periphery of the connecting rod connector 34, the connecting rod connector 34, which corresponds to a conventional crosshead, can be made smaller. the result,
This means that the reciprocating inertia can be reduced, and the vibration and noise of the Stirling engine itself can also be reduced.

Further, since the side force acting on the displacer piston rod 17 is also received by the linear rolling bearing 33, the friction loss due to contact sliding can be reduced as in the case of the power piston rod 22.

It goes without saying that the basic structure of the present invention can be applied not only to Stirling engines but also to reciprocating internal combustion engines and compressors.

〔Effect of the invention〕

As described above, according to the present invention, the bearing is fixed to the inner wall of the cylinder via the bearing housing, and the outer periphery of the power piston rod is supported by the bearing so as to be able to reciprocate. Reciprocating sliding friction loss due to acting side forces can be reduced, making it possible to achieve higher engine efficiency.

Furthermore, the reciprocating inertia of the portion corresponding to a conventional crosshead can be reduced, resulting in lower vibration, lower noise, and quieter operation.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a typical structure of a conventional Stirling engine, and FIG. 2 is a diagram showing a structure of a Stirling engine according to an embodiment of the present invention. 17...Displacer piston rod, 18.
...Power piston, 22... Rod for power piston, 31.32... Linear rolling bearing, 32...
Bearing housing, 34...Conrod connector, 11
．． 12... Power piston connecting rod, 7... Crankshaft. In the drawings, the same reference numerals indicate the same or equivalent parts. Agent Patent Attorney Ken Hayase - 0 Figure 1 Figure 2 Procedural Amendment (Voluntary) August 8, 1981 2. Name of the invention Stirling Engine 3. Relationship with the person making the amendment. Address of the patent applicant. 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name
(601) Mitsubishi Electric Co., Ltd. Representative: Hitoshi Katayama 4, Agent Address: Shin-Osaka Yachiyo Building, 4-1-45 Miyahara, Yodoyo-ku, Osaka Name (8181) Ken Hayase, Patent Attorney 5. Details subject to amendment Column 6 of the scope of claims of the book, content of amendment (11 The claims of the specification are amended as shown in the attached sheet. Claims above + 11 A power piston that reciprocates inside a cylinder and one end of which is a crank) A power piston rod and a connecting rod connector that are connected and fixed to each other connect a connecting rod that is rotatably connected to a shaft, and a power piston rod and a connecting rod connector that have an outer circumference fixed to the inner wall of the cylinder between the power piston and the connecting rod connector. a bearing housing provided with the rod fitted therein; and a bearing provided between the inner circumferential surface of the cough bearing housing and the outer circumferential surface of the rod so as to support the rod in a reciprocating manner. A Stirling engine characterized by: (2) The power piston rod 1 (7) inner peripheral part 1tZ
2. The Stirling engine according to claim 1, wherein a bearing is fixed to support the L-placer-piston rod so as to be able to reciprocate and slide. A＾7

Claims (2)

[Claims] (1) Hower histon Rond and connecting rod connectors connected and fixed to each other, which connect the power piston that reciprocates inside the cylinder and the connecting rod whose one end is rotatably connected to the crankshaft, and the power piston and connecting rod connectors. A bearing housing having an outer circumferential portion fixed to the inner wall of the cylinder and into which the iron is fitted, and a bearing housing that reciprocates the iron between the inner circumferential surface of the bearing housing and the outer circumferential surface of the iron. A Stirling engine characterized by comprising a bearing provided to slidably support the engine. (2) The power piston rond is formed in a cylindrical shape, and a bearing is fixed to the inner circumference of the power piston rond for slidably supporting the displacer piston rond in a reciprocating manner. Stirling engine according to scope 1.