JPH0430362Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention consists of two side rails, upper and lower, which are separated from each other in the upper and lower directions (in the axial direction), and which are pressed against the cylinder wall to apply oil to the side rails. This invention relates to a combination oil ring consisting of a spacer expander that provides a scraping effect.

[Conventional technology]

The combination oil ring installed in the oil ring groove of a piston that operates within the cylinder of an internal combustion engine has two upper and lower side rails that are separated and held by a spacer expander between the two side rails, and a side rail pressing piece of the spacer expander. It is pressed in the radial and axial directions by the cylinder wall to slide into sliding contact with the cylinder wall and seal the ring groove, and by appropriately scraping up and scraping down the lubricating oil on the cylinder wall, it functions to maintain and adjust an appropriate lubricating oil film.

This combination oil ring is forced into various postures along with the behavior of the piston during engine operation, but it is necessary to maintain a state in which the side rail is always in contact with the cylinder wall regardless of the behavior of the piston. However, as shown in Fig. 9, in the conventional combination oil ring, when the piston is slapped due to inclination or eccentricity of the piston, the two upper and lower side rails partially separate from the cylinder wall, and the two side rails are completely separated from the cylinder wall over the entire circumference. Since the oil ring does not come into sliding contact with the cylinder wall, it is difficult to perform a sufficient function as an oil ring. As a result, a problem has arisen in that the amount of lubricating oil consumed by the engine increases.

[Problem that the invention attempts to solve]

For example, even in the state of piston slap, if the upper and lower side rails can move independently and make sure sliding contact with the cylinder wall, and can scrape up and lower the lubricating oil, then the side rails can be moved independently to the piston and cylinder. It improves followability, increases airtightness inside the cylinder, prevents oil buildup, and reduces lubricant consumption. The followability of the side rail to the cylinder wall is ensured by the pressing force of the side rail in the radial direction by the spacer expander. This pressing force depends partly on the tension of the side rail itself, but is mainly provided by the radial pressing piece of the spacer expander. Note that the side rails are also pressed against the upper and lower surfaces of the oil ring groove in the oil ring groove of the piston by the axial component force of the spacer expander.

The problem to be solved by the present invention is how to use the expander to reliably press both side rails against the cylinder wall even in situations where piston slap occurs, for example.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce lubricating oil consumption by providing a combination oil ring that can bring the side rail into pressure contact with the cylinder wall under any conditions.

[Means for solving problems]

In order to achieve the above object, according to the present invention, the side rail pressing part of the spacer expander is connected to the main pressing piece and an auxiliary member located radially outward of the spacer expander and having lower rigidity than the main pressing piece. It is characterized by being composed of a pressing piece. That is, as shown in FIGS. 1 and 2, the side rail pressing piece of the spacer expander 11 has lower rigidity than the main pressing piece 13 (first stage) forming the conventional side rail pressing piece, and is in a free state. It has an auxiliary pressing piece 15 that protrudes radially outward (towards the cylinder wall) from the main pressing piece.

[Effect]

Since the auxiliary pressing piece 15 has weaker rigidity in the outer circumferential direction than the main pressing piece 13, during normal assembly, the auxiliary pressing piece 15 retreats to the same plane as the main pressing piece 13, and both come into contact with the side rails 21A and 21B. This is pressed outward in the radial direction, but even when the inner periphery of the side rail separates from the main pressing piece due to the inclination of the piston, for example, the auxiliary pressing piece 15 easily protrudes outward in the radial direction and presses the side rail. . Therefore, the presence of the auxiliary pressing piece allows the pressing part of the spacer expander to always come into contact with the inner circumferential side of the side rail even in the case of unusual piston behavior such as piston slap, thereby keeping the side rail in contact with the inner circumferential sliding surface of the cylinder. It works by pressing against the top and bottom surfaces of the piston groove, so
The upper and lower side rails can each move independently. In this way, the side rail is always in sliding contact with the cylinder and the top and bottom surfaces of the piston ring groove, increasing the airtightness inside the cylinder, preventing oil build-up not only during piston slap but also when the cylinder internal pressure is negative during the intake process, reducing lubricating oil consumption. reduce

〔Example〕

1 to 3 show a first embodiment of the present invention. In this embodiment, the pressing piece of the spacer expander 11 is a main pressing piece 13 corresponding to a conventional side rail pressing part, and a main pressing piece 13 that is more rigid or elastic than the main pressing piece 13. It is composed of a weak auxiliary pressing piece 15. FIG. 3 is a developed view of the material of the spacer expander 11,
This is bent as shown in FIG. 2 to form a ring-shaped spacer expander 11. The difference in rigidity or elasticity between the main pressing piece 13 and the auxiliary pressing piece 15 is as shown in FIG. This is obtained by forming one auxiliary pressing piece 15 at the end of the elastic piece 12. Alternatively, it is also possible to make the surface treatments of the main pressing piece 13 and the auxiliary pressing piece 15 different, thereby providing a difference in rigidity or elasticity. In that case, the main pressing piece may also be formed of only one elastic piece 12. In the embodiment shown in FIG. 1, the main pressing pieces 13 and the auxiliary pressing pieces 15 are arranged regularly and alternately in the circumferential direction, but they do not necessarily have to be arranged alternately. Further, the number of elastic pieces 12 forming the main pressing piece 13 or the auxiliary pressing piece 15 is not limited to that shown in the drawings.

Elastic piece constituting the main pressing piece 13 and auxiliary pressing piece 1
The elastic pieces forming the elastic pieces 5 may have exactly the same shape (of course, they may have different shapes), and the auxiliary pressing piece 15 is slightly closer to the cylinder wall 31 than the main pressing piece 13 in the free state during bending, as shown in FIG. The degree of bending may be adjusted so that it protrudes toward the side.

FIG. 7 shows the results of an engine test conducted on a water-cooled 4-cycle, 4-cylinder gasoline engine using an oil ring combined with the spacer expander according to the present invention shown in FIGS. 1 to 3. As shown in FIG. 7, the amount of lubricating oil consumed has been reduced by half compared to the conventional system shown in FIG. 9 (in which there is no equivalent to the auxiliary pressing piece 15). The engine used and operating conditions are as follows.

Engine specifications: 93PS/6200rpm Displacement 1300cc Cylinder: 73φmm x Stroke 77.4mm Operating conditions: 2400rpm x -660mmHg Load Operating time: 3Hr According to the present invention, as shown in Figure 8, the side rail 21A can be used even when the piston is tilted. (or 21B)
It was confirmed that the spacer expander 11 was reliably pressed against the cylinder wall 31 by the auxiliary pressing piece 15, and that it was functioning to raise and lower the oil. In addition, in FIG. 8, 40 is a piston,
41 indicates oil ring grooves, respectively.

Figures 4 to 6 show a spacer expander 11' according to another embodiment of the present invention, in which the auxiliary pressing piece 15' is different from the embodiment shown in Figures 1 to 3.
The main pressing piece 13 is different in that it is not bent into the same shape as the main pressing piece 13, and stands straight upward without forming a U-shaped portion in FIG. The auxiliary pressing piece 15' only needs to have the part that contacts the side rail projecting further toward the cylinder wall (to the right in Figure 4) than the main pressing piece 13, and the shape of the other parts is not important. . Therefore, FIGS. 4 to 6 show examples of different shapes of such auxiliary pressing pieces 15', which can be modified and changed in various ways.

According to the embodiment shown in Figs. 4 to 6, the auxiliary pressing piece 15' is shorter than that in Figs. It is also easy to bend.

Figure 5 shows the spacer expander 1 shown in Figure 4.
1', and FIG. 6 shows a developed view of the material.

[Effect of idea]

As explained above, according to the present invention, the side rail pressing piece of the spacer expander is used as the main pressing piece, and the auxiliary pressing piece is located radially outward of the spacer expander and has lower rigidity than the main pressing piece. This configuration improves the followability of the upper and lower side rails to the cylinder wall and reduces lubricant consumption, especially when the combustion chamber becomes negative pressure during engine braking or when the piston slaps. It has great effects, such as suppressing the oil build-up phenomenon that occurs in

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of a spacer expander of a combination oil ring according to the present invention, and Fig. 2 is a front sectional view of a spacer expander of a combination oil ring according to the present invention.
3 is a developed view of the material forming the spacer expander of FIG. 1, FIG. 4 is a front sectional view of the spacer expander showing another embodiment of the present invention, and FIG. Figure 5 is a perspective view of the spacer expander shown in Figure 4, Figure 6 is a developed view of the material of the spacer expander shown in Figure 4, Figure 7 is a graph of oil consumption showing the effects of the present invention, and Figure 8. FIG. 9 is a sectional view showing the effects of the combination oil ring according to the present invention, and FIG. 9 is a sectional view showing the drawbacks of the conventional combination oil ring. 11... Spacer expander, 13... Main pressing piece, 15... Auxiliary pressing piece, 21A, 21B...
side rail.

Claims (1)

[Scope of utility model registration request] In a combination oil ring consisting of one upper and lower side rail and a spacer expander that presses the side rail against the cylinder wall, the side rail pressing part of the spacer expander is connected to the main pressing piece and from this to the outside of the spacer expander in the radial direction. 1. A combination oil ring characterized by comprising an auxiliary pressing piece located on the side and having lower rigidity than the main pressing piece.