KR100365115B1 - Piston ring of engine - Google Patents

Abstract

PURPOSE: A piston ring of an engine is provided to improve sealing performance against fuel gas and oil. CONSTITUTION: Grooves(15) are formed on both ends of a joint(13) of a piston ring(1) along with a circumference of the piston ring. Springs(17) and sealing members(19) are inserted to the grooves, respectively, so that the sealing members are elastically supported by the springs and movable in circumferential direction of the piston ring. The sealing members are pushed by the springs to contact with each other near the middle of the joint.

Description

Piston ring of engine

(Technology field)

The present invention relates to a piston ring of an engine, and more particularly to a compression ring that prevents leakage of fuel gas from the engine's combustion chamber to the crankcase and an oil ring that scrapes oil from the cylinder wall to prevent oil from entering the combustion chamber. It relates to a piston ring in which the sealing performance of fuel gas and oil is improved as a piston ring.

(Prior art)

As is known, the engine of the vehicle compresses and combusts fuel mixed gas sucked into the combustion chamber space defined by the cylinder block and the cylinder head by means of a piston, and transfers thermal energy of the combustion gas to the linear motion of the piston, thereby connecting. It is operated by the principle of switching to the rotational movement of the trunk shaft by the rod.

In order for the engine to perform optimally, a number of requirements must be provided, among others, to ensure that the combustion gas explosive force of the combustion chamber is converted to the vertical movement of the piston to the maximum and that the frictional resistance between the various moving parts of the engine is minimized. Is desired.

In more detail, for efficient engine output, the combustion gas must first be blocked from leaking from the combustion chamber into the crankcase through the gap between the cylinder block and the piston. To this end, the piston is provided with a compression ring to prevent gas leakage in the ring groove formed on the outer periphery, thereby keeping the combustion chamber as airtight as possible.

On the other hand, the engine inevitably generates friction between the moving parts such as the cylinder block, the cylinder head, the piston, and the connecting rod during its operation. As such, all friction between parts occurring during engine operation acts as a resistance to reduce the output of the engine, and wears down the parts to shorten the life of the engine and reduce engine performance.

Accordingly, the engine is provided with a lubrication device for supplying lubricating oil to the sliding parts of the above-described moving parts in order to minimize the reduction of engine output and the wear of the parts by friction of such moving parts. Naturally, lubricating oil is also supplied to the wall of the cylinder block which is subjected to continuous frictional contact by the piston to minimize frictional resistance.

However, the lubricating oil supplied to the wall of the cylinder block is introduced into the combustion chamber according to the vertical movement of the piston and combusted with the fuel, thereby increasing the lubricating oil consumption and releasing toxic fumes. Therefore, the piston has an oil ring fitted to the lower portion of the compression ring, which scrapes oil from the wall of the cylinder block and prevents it from entering the combustion chamber.

1 is a partial cross-sectional view of a typical engine cylinder block mounted with a piston ring, and FIG. 2 is a partial perspective view of a piston ring showing various joint structures of a conventional piston ring.

As shown, the piston ring 1 comprising the compression rings 3, 3 ′ and the oil ring 5 is fitted in a ring groove 9 formed concave in the piston 7 so that the cylinder block 11 and the piston 7 can be fitted. ), The piston ring (1) generally consists of a compression ring on the upper part of the piston (7) consisting of a first ring (3) and a second ring (3 ') and a lower oil ring (5). do.

When the piston ring 1 is manufactured in the shape of a complete circular band, not only the piston ring 1 cannot be inserted into the ring groove 9 formed narrower than the diameter of the piston 7, but also the thermal expansion caused by exposure to the engine's high temperature environment It is not possible to accommodate an increase in the length of the ring 1 along. Therefore, as shown in Fig. 2, the piston ring 1 is not formed in a complete band shape, and a joint 13 having a gap at a predetermined interval is formed in one portion of the piston ring 1.

Examples of the joint 13 type of the piston ring 1 include butt joints having vertically cut joints (see FIG. 2A), step joints having stepped joints (see FIG. 2B), and mirrors. Slanted joints having a photographic joint (see FIG. 2C);

If the joint 13 of the piston ring 1 has a wide gap, the airtightness and oil removal performance will be reduced. On the contrary, if the gap is narrow, the piston ring will be damaged when the piston ring is thermally swelled, the cylinder wall is damaged, and the frictional resistance is increased. Problems occur. Thus, in determining the proper seam spacing of the piston ring 1, there is a difficulty in meeting the two opposing conditions described above as much as possible. However, since the conventional piston ring was difficult to satisfy both of the above contradictory conditions, the size of the seam of the piston ring was determined at either of the two faults.

In accordance with this technical background, the piston ring which overcomes the limitations of the joint structure of the conventional piston ring as well as excellent sealing performance of fuel gas and oil, and can eliminate all problems caused by thermal expansion of the piston ring. It is requested.

1 is a partial cross-sectional view of a typical engine cylinder block mounted with a piston ring.

Figure 2 is a partial perspective view showing various joint structures of a conventional piston ring.

3 is a cross sectional view of a seam portion of a piston ring according to the present invention;

4 is an exploded perspective view of one end of a joint portion of a piston ring according to the present invention;

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

1: piston ring 3, 3 ': compression ring

5: oil ring 7: piston

9: ring groove of piston 11: cylinder block

13: seam 15: home

17: spring 19: sealing member

The object of the present invention described above is achieved by providing a sealing member that elastically closes the gap between the joints in the joint portion of the piston ring.

More specifically, an object of the present invention is a piston ring in which a joint is inserted into a ring groove formed in a piston and has a gap of a predetermined interval, and is formed in a portion of the ring, wherein both ends of the piston ring are disposed along the circumference of the ring. An elongated groove is formed, and each of the grooves is inserted with a spring and a sealing member elastically moved by the spring and movable in the circumferential direction of the ring, and the two sealing members are pressed by the two springs. It is achieved by a piston ring characterized by abutting each other at approximately the center of the seam.

Hereinafter, with reference to the accompanying drawings will be described in detail a piston ring according to the present invention. The following specific examples merely illustrate the piston ring according to the present invention, but do not limit the scope of the present invention.

Fig. 3 is a cross sectional view of a seam portion of a piston ring according to the present invention, and Fig. 4 is an exploded perspective view of one end of a seam portion of a piston ring according to the present invention.

Piston ring 1 according to the present invention also, as shown in Figure 1, consists of a substantially circular ring shape corresponding to the outer circumferential shape of the piston 1, that is, the inner circumferential shape of the cylinder block 11, the piston (7) The joint 13 is inserted into the ring groove 9 formed in the cross section, and a part of the piston ring 1 has a gap of a predetermined interval.

As shown in Figs. 3 and 4, grooves 15 elongated along the circumference of the piston ring 1 are formed at both ends of the joint 13 according to the characteristics of the present invention. A spring 17 is fitted inside each of the grooves 15, and a small piston-shaped sealing member 19 is fitted to expose a predetermined length from the groove 15. The sealing member 19 is elastically movable by the spring 17 and is movable along the circumferential direction of the piston ring 1, and is pressed toward the joint 13 by each spring 17. Thus, the two sealing members 19 abut each other at approximately the center of the seam 13.

The length of the groove 15 is the length increase caused by the thermal expansion rate of the general piston ring 1 when exposed to the high temperature environment of the engine and the length occupied by the spring 17 and the sealing member 19 fitted thereto. It is set in consideration of. The length of the sealing member 19 is easily separated from the groove 15 from the groove 15 in consideration of the gap length of the joint 13, the depth of the groove 15, the work expansion coefficient of the piston ring (1). It is chosen to not be a length.

Since the piston ring 1 of the above-mentioned structure is provided with the joint 13 fundamentally, it can insert in the ring groove 9 of the piston 7 with a slightly open said joint part like a conventional piston ring. Once the piston ring 1 is inserted into the piston 7, the two sealing members 19 are connected to each other by elasticity of each spring 17 inserted into the groove 15 formed at both ends of the joint 13. Since it is pressed toward the center of 13, the seam 13 of the piston ring 1 is substantially sealed by the sealing member 19. Therefore, it is possible to prevent the leakage of the gas or oil described above with respect to the prior art.

On the other hand, when the length of the piston ring 1 becomes long due to the high heat of the engine, and the gap length of the seam 13 becomes short, the two sealing members 19 press the springs 17 while the piston ring 1 It is pushed into the groove 15 by a length corresponding to the length increase, and the two sealing members 19 are pressed against the center of the seam 13 by the springs 17 and are still in contact.

Accordingly, the sealing member 19 completely seals the narrowed joint 13 of the piston ring 1 while absorbing the increase in length due to thermal expansion of the piston ring 1, thereby causing damage to the piston ring, damage to the cylinder wall, and increased frictional resistance. The problem should not occur.

The piston ring according to the present invention can be applied to both the compression ring and the oil ring.

According to the piston ring according to the present invention described above, it is possible to improve the sealing performance of the fuel gas and oil as well as to eliminate all problems caused by thermal expansion. In addition, in determining the size of the joint gap of the piston ring, it is not necessary to precisely control the gap such as to make the gap of the joint as small as possible to accommodate the thermal expansion of the piston ring while maintaining the maximum sealing performance. Even if it enlarges, sealing performance will not fall.

Claims (1)

In a piston ring inserted into a ring groove formed in the piston and having a gap of a predetermined interval formed in a portion of the ring, grooves extending along the circumference of the ring are formed at both ends of the joint of the piston ring, Each groove is inserted with a spring and a sealing member elastically moved by the spring and movable in the circumferential direction of the ring, wherein the two sealing members are pressed by the two springs to contact each other at approximately the center of the seam. A piston ring characterized by the above-mentioned.

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