JPS5831446B2 - Internal combustion engine piston cooling system - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in piston cooling devices for internal combustion engines.

FIG. 1 shows a conventionally used piston cooling system for large marine internal combustion engines.

Since the piston 1 reaches a high temperature during operation, it is cooled with a cooling oil 2 made of lubricating oil or the like.

The piston rod 3 has central double tubular passages 4 and 5;
The coolant 2 flows into the piston 1 through a passage 4, and after cooling it is discharged to the outside from a discharge pipe 6 through a passage 5.

The passage 4 is connected to a telescopic tube 9 fixed to the arm metal fitting 8 through a passage inside the arm metal fitting 8 attached to a cross rad pin 7 that moves up and down with the piston rod 3.

The telescopic tube 9 moves up and down inside the outer tube 10 together with the piston 1.

A packing 11 is attached to the lower end of the outer tube 10, and a cooling oil pipe 1 is attached to the upper end.
It has 2.

During the vertical movement of the telescopic tube 9, the cooling oil 2 pumped from the cooling oil pipe 12 to the outer tube 10 is continuously transferred from the upper end of the telescopic tube 9 to the arm fitting 8.
→ Crosshead pin 7 → Passage 4 → Piston 1 route,
It is forced into the inside of the piston 1.

In this device, the outer tube 10 is a steel tube fixed to an air reservoir 14 fixed to the side of the cylinder jacket block 13 of the engine.

The disadvantage of the above device is that since the outer tube 10 is mounted apart from the cylinder jacket block 13, the telescopic tube 9 is far away from the piston 1, and therefore the arm fitting 8 has to be long and strong; In order to enable vertical movement of the tube 9, the frame 15
It becomes necessary to extend it to the outside of the telescopic tube 9.

Therefore, the engine as a whole becomes larger and heavier than necessary, making it an uneconomical device.

The purpose of the present invention is to provide a piston cooling device that can reduce the size, weight, and number of parts of an engine by paying attention to the above-mentioned points. The pipe is integrally formed inside the cylinder jacket block of the engine.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a sectional view showing the structure of an engine according to an embodiment of the present invention.

In the figure, each reference numeral indicates the same thing as in FIG. 1.

Piston 1, piston rod 3, oil passages 4, 5, discharge pipe 6,
The structures of the cross rad pin γ, arm hardware 8, and telescopic tube 9 are the same as in the case of FIG.

Note that 2 is cooling oil. The outer tube 10 is made integrally as part of the structure of the cylinder jacket block 13.

Since the cylinder jacket block is usually made of cast iron, the outer tube 10 is made as a cast hole in the cylinder jacket block.

The upper part of the outer tube 10, which is formed by a cast hole, is open to the side surface of the cylinder jacket book, and a cooling oil passage 12 is connected thereto.

Further, the outer tube 10 has a packing 11 at the lower end.

The air reservoir 14 is attached to the side surface of the cylinder jacket block 13 without incorporating the outer tube 10.

The frame 15 is reduced to a range that allows movement of the telescopic tube 9.

In the above embodiment, the outer tube 10 is a cast hole, but any hole formed inside the block 13 may be used.

That is, the block 13 may have a welded structure or may have a machined hole.

In the case of the above configuration, the piston cooling effect is similar to that of the conventional example shown in FIG.

As described above, the present invention has the following effects.

(1) The telescopic tube 9 can be brought closer to the piston 1.

Therefore, the arm hardware 8 can be made smaller.

(2) Since the vertical movement range of the telescopic tube 9 is closer to the center of the engine, the width of the frame 15 can be reduced.

(3) There is no need to make the outer tube 10 separately and attach it to an air reservoir, etc., and it is only necessary to change the shape of the cylinder jacket block, which reduces the number of parts and facilitates manufacturing.

(4) By reducing the size, weight, reducing the number of parts, and facilitating manufacturing as described in items (1) to (3) above, manufacturing costs can be reduced, materials can be saved, and reliability can be improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the engine showing a conventional piston cooling device for a crosshead type internal combustion engine, and FIG. 2 is a sectional view of the engine showing one embodiment of the device according to the present invention. 1...Piston, 2...Cooling oil, 3.
... Piston rod, 4, 5 ... Oil passage, 6
...Discharge pipe, 1 ... Rad pin to cross, 8 ... Arm hardware, 9 ... Telescopic tube, 10 ... Outer tube, 11...
Packing, 12...Cooling oil pipe, 13...
- Cylinder jacket block, 14... Air reservoir, 15... Frame.

Claims (1)

[Claims] 1. A piston cooling device for a crosshead internal combustion engine having an outer tube fixed to the engine and a telescopic tube inserted into the outer tube and reciprocating in conjunction with the piston to forcefully feed cooling fluid into the piston, wherein the telescopic tube A piston cooling device for an internal combustion engine, characterized in that an outer tube into which the tube is inserted is integrally formed inside a cylinder jacket block of the engine.