JPH0138281Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an oil ring used for lubricating oil control among piston rings used in internal combustion engines. More specifically, it relates to an improvement in a combination oil ring consisting of a spacer expander and a side rail that is pressed in the outer circumferential direction by the spacer expander and is pressed against the inner wall surface of the cylinder. It is.

<Prior art> In a reciprocating internal combustion engine, as the piston reciprocates, lubricating oil is efficiently scraped from the inner wall of the cylinder and skillfully circulated back to prevent it from entering the combustion chamber. An oil ring is installed in the ring groove. This kind of oil ring is
Various shapes have been devised to improve not only the material quality but also the functionality. As shown in Japanese Patent Publication No. 33-10104, an oil ring that has been commonly used in the past is made up of a corrugated flat plate, and the corrugation forms a series of outer and inner protrusions. There is a spacer expander in which outer protrusions and inner protrusions are arranged alternately, and protrusions are provided on the upper and lower end surfaces of each inner protrusion, respectively, which are formed into an annular shape, and upper and lower parts of the annular spacer expander. There is a combination oil ring consisting of a pair of annular side rails arranged on both end surfaces, the inner annular surface of each side rail is supported by the projection, and the outer circumferential surface of the side rail is in contact with the inner wall of the cylinder. . Although its performance has been fully demonstrated, usage conditions have become increasingly severe in recent years, such as initial conformity to the cylinder inner wall surface, followability to the cylinder surface after long-term engine operation, and constant and even pressure. Maintaining pressure has become a challenge. Furthermore, if the bottom of the oil ring groove of the piston is deep, there are problems such as unstable assembly and unstable seating within the ring groove.

<Problems to be solved by the invention> In view of the above, the purpose of the invention is to improve the spacer expander of the combination oil ring so that it can follow the cylinder and always have a sufficiently uniform surface pressure.
It is an object of the present invention to provide a combination oil ring that can easily be assembled with reliability and good alignment (that is, stable seating in the ring groove) with respect to oil ring grooves of various pistons.

<Means for Solving the Problems> In order to achieve the above object, the features of the present invention consist of a corrugated flat plate having an annular shape as a whole, and the corrugation has a series of outer convex portions and a series of inner convex portions. The convex portions are connected by a connecting member extending in the radial direction, and the upper and lower edges of the inner convex portion in the axial direction are provided with spacer expanders integrally provided with protrusions. A combination oil ring comprising a pair of side rails disposed above and below a spacer expander, wherein the spacer expander has a notch extending in the axial direction on either one of the upper and lower protrusions on the inner protrusion; There is provided at least one projecting piece supported by one side of the part and bent in the inner circumferential direction from the inner convex part.

The combination oil ring of the present invention has a spacer expander with a new structure in order to solve the problems of conventional combination oil rings, such as the inability to follow the cylinder and the inability to always obtain sufficiently uniform surface pressure. .

<Function> As described above, in the combination oil ring of the present invention, since the protrusion part that is press punched and bent appropriately is provided on the inner convex part of the spacer expander, it has flexibility in the vertical and circumferential directions. Therefore, the followability of the side rail to the cylinder is improved, uniform surface pressure is obtained, and lubricating oil consumption can be reduced. Furthermore, since the projecting piece is bent in the inner circumferential direction, when it is installed in the oil ring groove, its free end can be placed at an optimal position with respect to the bottom surface of the oil ring groove. That is, reliable assembly and good centering (stable seating within the ring groove) can be easily achieved with respect to the oil ring groove of various pistons. The size and number of the protruding pieces are determined depending on the strength and elastic behavior of the spacer expander, and other requirements.

<Example> An example embodying the present invention will be described below based on the drawings.

FIG. 1 shows a state in which the combination oil ring of the present invention is mounted on a piston of a reciprocating internal combustion engine. 6 in the figure is the piston, and its oil ring groove 6
A combination oil ring 1 is attached to 1. The combination oil ring 1 includes a pair of side rails 3,
3 and a spacer expander 2 interposed therebetween to hold the side rail 3 and press it against the cylinder inner wall 4. The spacer expander 2 is formed into a radial wave shape,
The inner convex portion 21 has a protrusion 211 that contacts the inner circumferential side surface of the side rail 3 and is spaced apart from the circumferential side surface of the spacer expander 2 . The protrusion 211 has an angle with respect to the axial direction. This is to press the side rail 3 not only in the radial direction but also in the vertical direction to obtain a sealing effect on the cylinder inner wall 4 and the side wall surface of the oil ring groove 61.

Reference numeral 62 is a hole for returning the oil in the oil ring groove 61 to the inside of the piston. The side rail 3 is made of a steel ribbon, and the portion 5 on its outer circumferential surface that contacts the cylinder inner wall 4 includes:
If necessary, surface treatment such as hard chrome plating may be applied.

FIG. 2 is a perspective view showing a part of the spacer expander according to the present invention, and the spacer expander 2 is composed of an annular corrugated flat plate as a whole.
A series of inner protrusions 21 and a series of outer protrusions 22 are arranged alternately, and these protrusions are connected by a connecting member to form a wave shape in the circumferential direction. Protrusions 2 extending in the axial direction are provided at both upper and lower ends of each inner convex portion 21.
11 is provided, and a pair of side rails are disposed to engage with this as described above. In the present invention, the inner protrusion 21 of the spacer expander 2 has a notch extending in the axial direction on either one of the upper and lower protrusions 211.
At least one protruding piece 212 is provided which is supported by one side of the inner protrusion 21 and bent in the inner circumferential direction from the inner convex part 21. This protruding piece can be easily formed by press punching and bending it appropriately. Further, it is preferable that the protruding pieces 212 are provided alternately on the inner protrusions around the entire circumference of the expander as shown in the figure. With this configuration, the flexibility of the spacer expander in the vertical direction and the circumferential direction is increased, and therefore, the followability of the side rail to the cylinder is improved, and uniform surface pressure can be obtained. In the figure, one protruding piece is provided on each inner convex part,
The number can be determined depending on the strength and elastic behavior of the spacer expander and other requirements. In addition, as shown in FIG.
By adjusting the bending angle θ of 12,
When installed in the oil ring groove, their free ends can be located at the optimal position with respect to the bottom surface of the oil ring groove, ensuring assembly reliability and good centering for various piston oil ring groove depths. Matching (stable seating within the ring groove) can be easily achieved.

Incidentally, reference numeral 23 in FIG. 2 is a punched hole for oil circulation.

<Effects of the invention> As described above, in the present invention, since the spacer expander is properly provided with the projecting piece, the flexibility of the spacer expander in the vertical direction and the circumferential direction is increased, and thus the flexibility of the spacer expander against the cylinder of the side rail is increased. Followability is improved, uniform surface pressure is obtained, and reliable assembly and good centering can be easily obtained for various piston oil ring groove depths. Therefore, the combination oil ring of the present invention can improve the sealing effect and reduce the consumption of lubricating oil, and the practical benefits of its implementation are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a combination oil ring of the present invention installed in an oil ring groove of a piston, and FIG. 2 is a partially cutaway perspective view showing an embodiment of the combination oil ring of the present invention. be. Symbols in the figure are: 1...Combination oil ring, 2...Spacer expander, 21...Inner convex portion, 22...Outer convex portion, 211...Protrusion, 2
12... Projection piece, 3... Side rail, 4... Cylinder inner wall, 5... Side rail outer peripheral surface, 6...
Each piston is shown.

Claims (1)

[Claims for Utility Model Registration] (1) Consisting of an annular corrugated flat plate as a whole, the corrugations include a series of outer convex portions and a series of inner convex portions alternately, and both of these convex portions extend in the radial direction. The spacer expander is connected by a connecting member, and has projections integrally formed on the upper and lower axial edges of the inner convex portion, and a pair of side rails arranged above and below the spacer expander. In the combination oil ring, the inner convex portion of the spacer expander has a notch that extends in the axial direction on either one of the upper and lower protrusions, is supported by one side of the inner convex portion, and is supported by one side of the inner convex portion, and extends in the inner circumferential direction from the inner convex portion. A combination oil ring characterized in that it has at least one protrusion portion that is bent. (2) The combination oil ring according to claim 1 of the utility model registration claim, characterized in that the spacer expander is provided with alternately bent protrusions on the inner convex portion extending over the entire circumference of the spacer expander. Combination oil ring.