KR19980036903A - Piston of car engine - Google Patents

Abstract

The present invention relates to a piston having a structure capable of reinforcing a lubricating oil removing function of an oil ring. The present invention relates to a lower compression ring groove and an oil ring to return the lubricating oil raised to the compression ring groove (5) to the oil ring groove (6). The communicating oil balls are formed radially along the circumferential direction. Alternatively, the oil ring groove of the piston may be formed with a curved surface to prevent the lubricant from rising.

Description

Piston of car engine

1 is a perspective view of a piston of a conventional automobile engine.

2 is a cross-sectional view of the main portion of the piston shown in FIG.

3 is a sectional view of principal parts of a piston of a motor vehicle according to the first embodiment of the present invention.

4 is a sectional view of principal parts of a piston of a motor vehicle according to a second embodiment of the present invention.

5 is a sectional view of principal parts of a piston of a motor vehicle according to a third embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

1: piston head 2: ring belt

5: Compression ring groove 6: Oil ring groove

7: oil ball 8: auxiliary groove

[Purpose of invention]

The present invention relates to a piston of an automobile gasoline engine, and more particularly, to a piston of an automobile engine having a structure capable of reinforcing a function of an oil ring.

[Technical Field to which the Invention belongs and Prior Art in the Field]

As is well known, the piston of an automobile gasoline engine is reciprocated by a mixed gas compressed in an expansion stroke inside a cylinder, and the connecting rod converts the linear movement of the piston into the rotational movement of the crankshaft, thereby Rotate the connected wheels to drive the car.

This piston consists of a piston head 1, a ring belt 2, a pin boss (not shown) and a skirt 4, as shown in FIGS. 1 and 2.

The ring belt 2 is formed with a plurality of ring grooves 5 and 6 into which the piston ring is fitted. The piston ring is a cast iron or steel ring which is partially cut and elastic, and may be classified into a compression ring and an oil ring according to a function. Typically, the piston of an automobile gasoline engine is formed with two compression ring grooves 5 and one oil ring groove 6 so that two compression rings and one oil ring are fitted from the top of the ring belt.

The compression ring is in close contact with the piston and the cylinder wall to maintain the airtightness of the combustion chamber and to transfer heat received by the piston to the cylinder wall during the expansion stroke. On the other hand, the oil ring has a function of scraping excess lubricant out of the lubricant oil for lubricating the friction surface of the piston and the cylinder wall, and returning the lubricant oil to the crankcase through small holes formed in the oil ring groove 6.

[Technical problem to be achieved]

However, in the conventional piston as described above, since the oil ring occupies most of the space of the oil ring groove and blocks the small holes formed in the oil ring groove, the excess lubricant is not sufficiently filtered out, and thus, into the combustion chamber. Hazardous components may be included in the exhaust gas by the inflow of lubricating oil, and carbon deposits may form during combustion, contaminating spark plugs, and depositing carbon deposits on the intake / exhaust valves or causing deadlocks in the ring. Thereby, there existed a problem that the performance of an engine fell.

In addition, there is a problem in that the consumption of the lubricating oil increases as the lubricating oil flows into the combustion chamber.

Accordingly, an object of the present invention is to provide a piston of an automobile engine having a structure in which a function of returning lubricating oil scratched by the oil ring to the crankcase is enhanced so as not to flow into the combustion chamber.

[Configuration and Function of Invention]

In order to achieve the above object, the piston of the automobile engine according to the first embodiment of the present invention, in the piston of the automobile engine, the lower compression ring groove and the oil ring to return the lubricating oil raised to the compression ring groove to the oil ring groove A plurality of oil balls for communicating the groove is characterized in that it is formed radially along the circumferential direction.

Alternatively, in the piston of an automobile engine, the oil ring groove of the piston is formed by a curved surface to prevent the lubricating oil from being raised to be achieved by the piston of the automobile engine according to the second embodiment of the present invention. Can be.

In addition, in the piston of the automobile engine, it can be achieved by the piston of the automobile engine according to the third embodiment of the present invention, characterized in that the groove is formed on the outer peripheral surface of the piston between the lower compression ring groove and the oil ring of the piston. .

EXAMPLE

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

3 shows a first embodiment according to the invention.

As shown in FIG. 3, the piston according to the present invention has an oil hole 7 communicating the oil ring groove 6 and the lower compression ring groove 5 radially along the circumferential direction of the piston. Therefore, the excess lubricant oil which has not been filtered out by the oil ring and rises into the compression ring groove 5 is passed back through the oil hole 7 which communicates the oil ring groove 6 and the lower compression ring groove 5. Will come down.

On the other hand, FIG. 4 shows a second embodiment according to the present invention.

As shown in FIG. 4, the piston according to the present invention is formed with serrated curved surfaces on the upper and lower surfaces of the oil ring groove 6, respectively. Therefore, the surface area of the upper and lower surfaces of the oil ring groove 6 becomes wider, so that the amount of lubricating oil that can be accommodated in the oil ring groove 6 increases.

Also shown in FIG. 5 is a third embodiment according to the invention.

As shown in FIG. 5, the piston according to the present invention has an auxiliary groove 8 formed on the outer circumferential surface between the oil ring groove 6 and the lower compression ring groove 5. Therefore, the extra lubricating oil which is not filtered by the oil ring and rises toward the compression ring groove is stopped by the auxiliary groove 8 and is again filtered by the oil ring as the piston moves.

[Effects of the Invention]

According to the present invention as described above, since the extra lubricant oil is prevented from flowing into the combustion chamber by means of reinforcing the function of the oil ring, it is possible to prevent the generation of harmful components of the exhaust gas and the deterioration of engine performance due to the combustion of the lubricant oil. In addition, the consumption of lubricating oil can also be reduced.

Claims (3)

In a piston of an automotive engine, a piston of an automotive engine, characterized in that a plurality of oil balls communicating with the lower compression ring groove and the oil ring groove are radially formed along the circumferential direction so as to return the lubricating oil raised to the compression ring groove to the oil ring groove. . A piston of an automobile engine, wherein the oil ring groove of the piston is formed in a curved surface to prevent the lubricant oil from rising. A piston of an automotive engine, wherein the groove is formed on the outer circumferential surface of the piston between the lower compression ring groove and the oil ring of the piston.