JP2546846B2 - Oil splash prevention porous body fixing structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fixing structure of a porous body used for a heat-driven engine, a dry compressor or the like for preventing scattering of lubricating oil.

[Conventional technology]

FIG. 4 shows a conventional Stirling engine disclosed in Japanese Patent Application Laid-Open No. 62-32267. In this Stirling engine, a structure for preventing oil from propagating to the power piston side is shown. That is, the conventional Stirling engine used for a heat-driven engine or a dry compressor has a problem that the operating efficiency becomes low when oil enters the working chamber side.
Various scattering prevention structures have been proposed so that the lubricating oil on the sliding surface of the crosshead does not scatter to the power piston side above it.

In FIG. 4, reference numeral 1 is a crankcase, and the crankcase 1 is used as a basis for assembling all the components of the Stirling engine. Reference numeral 2 is a flange fixed to a hole machined in the crankcase 1 with a fastening component such as a bolt, 3 is a bearing housing fixed to the crankcase 1 similarly to the flange 2, and 4 is fixed to the crankcase 1. A flange 5 is a bearing fixed to the bearing housing 3, 6 is a bearing fixed to the flange 2, and 7 is a crankshaft, which is rotatably held by the bearings 5 and 6 to externally generate power generated by the Stirling engine. Is to be transmitted to. A mechanical seal 8 is attached to the crankshaft 7 and is for sealing the gas in the crankcase 1. Further, 9 and 10 are balance weights for balancing the rotation of the crankshaft 7, which are fixed to the crankshaft 7. 11, 12 are power piston connecting rods connected to the crankshaft 7 by bearings, 13 is a crosshead connected to the power piston connecting rods 11 and 12, and include a power piston rod 14 and a power piston 15 Are connected. Further, the outer circumference of the crosshead 13 is fitted to the inner circumference of the cylinder 16 so as to have a bearing function so that it can slide back and forth.

Reference numeral 17 is an oil absorbing material provided in the space between the crosshead 13 and the power piston 15, and is made of a material that has air permeability and oil absorption. It absorbs oil attached to the piston rod 14. Reference numeral 24 denotes a scattering prevention porous body provided immediately above the crosshead 13 and fixed to the crosshead 13. This is for suppressing the oil scattered from the sliding portion of the crosshead 13 and rising as little as possible. Reference numerals 18a and 18b denote first and second communication holes, respectively, which communicate the space for housing the oil absorbing material 17 and the crank chamber, that is, the space in the crankcase 1, with 18a being the crosshead 13 and 18b being the cylinder 16 And the wall of the crankcase 1, respectively. Reference numeral 26 is an oil absorbent retainer that holds the oil absorbent 17.

Reference numeral 19 denotes a displacer connecting rod, which is rotatably connected to the crankshaft 7 by a bearing. 20 is a piston pin, 21 is a displacer rod,
Is connected to the displacer connecting rod 19 through the crosshead 13, the power piston rod 14 and the power piston 15 and is fixedly connected to the displacer piston 22. The reference numeral 23 is a lubricating oil for lubricating the moving part of the Stirling engine accumulated at the bottom of the crankcase 1.

FIG. 5 shows an example of a conventional fixing structure for a shatterproof porous body. In this figure, reference numeral 24a is a fixed plate, and a gap with the upper surface of the crosshead is held by a bush 24d. 24f is a washer that presses the porous body 24b, and 24c is a bush whose height dimension is almost equal to the height dimension of the porous body 24b. The structure is such that the weak porous body does not buckle.

[Problems to be solved by the invention]

As described above, since the porous body is formed of a foam metal or a sponge-like substance, its strength is very low and it cannot be directly fastened with a bolt or the like. Therefore, the porous body is fixed and held by the structure shown in FIG.

By the way, since the crosshead 13 repeats a reciprocating motion, a reciprocating inertial force acts not only on the crosshead 13 but also on the porous body 24b, the fixing plate 24a and the like. Naturally, a buckling force acts on the porous body 24b on the seat surface of the washer 24f.
If the engine is operated for a long time in such a situation or if intermittent operation is repeated, the surface of the porous body 24b buckles and sinks (see FIG. 6). As this phenomenon progresses, the porous body 24
The effect of fixing b was lost, the amount of oil scattered increased due to the floating of the porous body 24b, and eventually, the porous body 24b was sometimes destroyed.

As described above, in the conventional fixed structure of the oil scattering porous body,
There is a problem that the highly reliable effect cannot be obtained for a long time, the splash prevention plate (porous body) floats, the amount of oil splashes increases, and in the worst case, the splash prevention plate breaks. there were.

The present invention has been made to solve the above problems, and can securely fix the oil scattering prevention porous body, and no problem occurs even if it is operated for a long time, and the scattering prevention of the porous material It is an object of the present invention to obtain a fixed structure of an oil scattering prevention porous body in which a plate does not float.

[Means for solving problems]

The fixing structure of the oil splattering prevention porous body in the Stirling engine and the like according to the present invention has a hole for inserting the head of the fixing pin into the porous body for preventing lubricating oil splattering, and the hole of the fixing pin is provided in this hole While inserting the portion, an adhesive is poured to fix the fixing pin and the porous body to each other.

[Operation] In the present invention, the foam metal shatterproof plate does not float even when the engine is operated for a long time, and the adhesive penetrates into the holes of the foam metal, so that a strong fixing effect is obtained. .

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. The overall structure of the engine to which the present invention is applied is the same as the conventional one shown in FIG. FIG. 1 shows a fixing structure of a shatterproof porous body according to an embodiment of the present invention. Reference numeral 30 denotes a foam metal which is a porous body, and a through hole 30a into which a pin portion of a set screw 31 can be inserted is formed. 31 is a set screw for fixing the foam metal 30 to the crosshead 13, and the upper part thereof is a hole of the foam metal 30.
It is formed so that it can be inserted into 30a, and an uneven portion for preventing the adhesive from coming off is formed, and the lower portion is fixed to the crosshead 13 by screw coupling. An adhesive 32 is injected into the upper portion of the through hole 30a of the foam metal 30, and penetrates into the concave and convex portions of the set screw 31 and above the set screw and at the same time penetrates into the hole portion of the foam metal 30.

In the fixing structure of the porous body according to the present embodiment, the fixing adhesive 32 penetrates into the recesses of the set screw and the holes of the foam metal to obtain a strong fixing force and the set screw 32 is loosened. Nor.

Therefore, even if the inertial force due to the reciprocating motion of the crosshead 13 due to the rotation of the engine acts on the porous body (foamed metal) 30 having a low strength, the floating phenomenon and the breakage of the porous body 30 can be eliminated. As a result, it is possible to prevent an inconvenience caused by an increase in the amount of oil scattered or destruction over a long period of time.

In the above embodiment, an example in which the set screw 31 is provided with a concave portion for preventing the adhesive from coming off is shown. However, as shown in FIG. May be. Further, as shown in FIG. 3, the screw head may have a spiral shape. Furthermore, if the adhesive strength of the adhesive is strong, the upper part of the set screw may be pin-shaped (straight).

The present invention can be applied to any engine as long as it seals the piston portion without lubrication, and can be applied to, for example, a non-lubricated compressor, a Stirling engine, a Stirling cooler, a GM refrigerator, or the like.

Furthermore, the material of the foam metal, the porosity, the thickness, the diameter, the number of setscrews, etc. are not limited.

〔The invention's effect〕

As described above, according to the present invention, the oil scattering prevention porous body is provided with the hole into which the head of the fixing pin is inserted, and the fixing pin head is inserted into this hole and the adhesive is poured into the hole, Since they are fixed to each other, the amount of oil splashing does not increase even when the engine speed increases or even during long-term operation. Further, there is an effect that the conventional destruction of the porous body can be prevented and a highly reliable fixed structure of the oil scattering prevention porous body can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a fixing structure of an oil scattering prevention porous body of a Stirling engine according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing other embodiments of the present invention, respectively. FIG. 5 is a sectional view showing a conventional Stirling engine, fifth.
FIG. 6 is a sectional view showing a conventional fixing structure of an oil splash prevention plate,
The figure is a diagram for explaining the problems of the conventional structure. 13 ... Crosshead, 30 ... Porous body such as foam metal, 30a
…… Hole, 31 …… Set screw, 32 …… Adhesive. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (6)

(57) [Claims] 1. An engine which seals a piston portion without lubrication, and which is provided above a crosshead fixedly connected to a piston which receives a pressure fluctuation generated in a cylinder,
A structure for fixing a porous body for preventing scattering of lubricating oil from the sliding surface of the crosshead, wherein a pin for fixing a porous body is fixed to the upper surface of the crosshead, and the fixing body is fixed to the porous body. A hole into which the head of the pin for insertion is inserted is formed, and the porous body is inserted into the hole of the porous body in the head of the fixing pin, and an adhesive is injected into the hole to attach the pin to the fixing pin. A fixed structure of oil scattering prevention porous body characterized by being fixed. 2. The fixing structure of the oil splattering prevention porous body according to claim 1, wherein the porous body is formed of foam metal. 3. The fixing structure for an oil spill prevention porous body according to claim 1 or 2, wherein the fixing pin has an uneven portion formed on its head. 4. The fixing structure for an oil splattering prevention porous body according to claim 1 or 2, wherein the fixing pin has knurls formed on its head. 5. The fixing structure for an oil splash preventing porous body according to claim 1 or 2, wherein the fixing pin has a head portion formed in a spiral screw shape. 6. The oil according to any one of claims 1 to 5, wherein the fixing pin is fastened and fixed to a screw hole formed in the upper surface of the crosshead. Fixed structure of anti-scattering porous body.