JPS61233269A - Combination oil ring - Google Patents

Abstract

PURPOSE:To provide a uniform radial direction and surface distribution on an upper and a lower surface, by a method wherein an internal peripheral projection and an external peripheral projection are respectively formed on at least either upper or lower end in the direction of an axis of the internal and the external projection on a spacer expander. CONSTITUTION:A pad part, which has an internal peripheral projection 26b, circumferentially connected to at least either upper or lower end 26a in the direction of an axis of an internal projection and cut away from a coupling member 24, is formed to an internal projection 21 of a spacer expander 2. A side rail pressure collecting part, which has an external projection 25b, circumferentially integrally connected to either of upper and lower ends 25a in the direction of an axis of an external projection and cut away from the coupling member 24, is formed to the external projection of the spacer expander 2. This enables uniform maintenance of surface distribution on the upper and lower surface of the ring groove of a piston 6 by means of a side rail 3.

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 a reciprocating internal combustion engine. More specifically, a spacer expander, and sides that are disposed above and below the spacer expander and are pressed in the outer circumferential direction by the spacer expander to come into pressure contact with the inner wall surface of the cylinder and also with the upper and lower surfaces of the ring groove of the piston. This invention relates to an improvement of a combination oil ring consisting of a rail.

<Prior art> In a reciprocating internal combustion engine, as the piston reciprocates, the lubricating oil on the inner wall of the cylinder is efficiently scraped, and in order to skillfully circulate it back and prevent it from going to the combustion chamber. An oil ring is installed in the ring groove of the ring groove.In addition to improving the material, various shapes have been devised to improve the function of these oil rings.Oil rings that have been used in conventional sizes For example, there is an oil ring shown in Japanese Patent Publication No. 33-10104.This oil ring is as shown in Fig. 4.5, and the spacer expander used for this oil ring is shown in Fig. 4. As shown, it is made of a corrugated flat plate as a whole, and the corrugation has a series of outer protrusions 22 and inner protrusions 21, and each outer protrusion and inner protrusion are arranged alternately, and each A spacer expander 2 is formed into an annular shape, with projections 211 provided on the upper and lower end surfaces of the inner convex portion, and pressure receiving surfaces 221 integrally provided at the upper and lower ends of the outer convex portion in the axial direction to support the side rails. As shown in FIG. 5, it consists of a pair of annular side rails 3.3 disposed on both upper and lower end surfaces of this annular spacer expander, and the inner annular surface of each side rail is supported by the projection 211, This is a combination oil ring configured so that the outer peripheral surface of the side rail is in contact with the cylinder inner wall 4, and the upper and lower surfaces of the side rail are in pressure contact with the upper and lower surfaces of the ring groove 61 of the piston.It has been fully demonstrated in terms of its performance, but in recent years it has gradually improved. Due to increasingly harsh operating conditions, the inner periphery of the side rail and the protrusion that makes contact tend to wear out, resulting in initial conformation to the inner cylinder wall surface and ability to follow deformation of the cylinder surface after long-term engine operation. In addition, it is difficult to maintain an even pressure distribution on the upper and lower surfaces of the ring groove of the piston due to the side rails, making it difficult to obtain a sufficient sealing effect. However, this results in the problem of increased lubricant consumption.

<Problems to be Solved by the Invention> In view of the above, the purpose of the present invention is to improve the spacer expander of the combination oil ring and improve the followability to the cylinder and the top and bottom surfaces of the piston ring groove.
To provide a combination oil ring in which both surface pressures are sufficiently equalized.

<Means for Solving the Problems> In order to achieve the above object, the features of the present invention are as follows:
It consists of a generally annular corrugated flat plate, the corrugations having a series of outer convex portions and a series of inner convex portions alternating with each other, and these convex portions are connected by a connecting member extending in the radial direction. A combination oil ring consisting of a spacer expander having projections integrally provided at the upper and lower ends of the inner convex portion in the axial direction, and a pair of side rails disposed above and below the spacer expander. A pad having at least one of the protrusions at the upper and lower axial ends of the inner convex part, and an inner circumferential protrusion that is integrally connected to at least one of the protrusions in the circumferential direction and separated from the connecting member. and at least one of the upper and lower axial ends of the outer convex part, and an outer peripheral protrusion that is integrally connected to at least one of the upper and lower ends in the circumferential direction and separated from the connecting member. The present invention is characterized in that a side rail pressure receiving portion is formed.

The combination oil ring of the present invention solves the problem in the conventional combination oil ring that the cylinder and piston follow the upper and lower surfaces of the tongue groove, and the surface pressure that influences the followability is not sufficiently uniform. It is a new structure of panda.

As described above, in the combination oil ring of the present invention, at least one of the protrusions at the upper and lower axial ends of the inner convex part of the spacer expander is connected to at least one of the protrusions in the circumferential direction. and a pad portion having an inner circumferential protrusion separated from the connecting member, and a pad portion that is integral with at least one of the upper and lower axial ends of the outer convex portion and at least one of the upper and lower ends in the circumferential direction. In order to form a side rail pressure-receiving part having an outer peripheral protrusion that is connected to the connecting member and separated from the connecting member by press punching or the like, the contact area of the contact area between the inner periphery of the side rail and the spacer expander and the side rail are By increasing the pressure-receiving area that supports the side rail, it is possible to prevent wear on the contact area with the inner circumference of the side rail, making it possible to follow the cylinder and always maintain sufficient pressing force. The surface pressure distribution on the top and bottom surfaces of the ring groove can be maintained evenly, and a sufficient sealing effect can be obtained.
It is possible to reduce lubricating oil consumption. The extended length, axial width, etc. of the protruding parts of the pad part and the side rail pressure receiving part are determined in accordance with the strength of the spacer expander and other necessary conditions. <Examples> Examples embodying the present invention will be described below based on the drawings. In addition, the same parts as those explained in FIG. 4 and FIG. 5 as a conventional combination oil ring are given the same reference numerals.

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. In the figure, 6 is a piston, and the combination oil ring 1 is installed in the oil ring groove 61 of the piston. The combination oil ring is composed of a pair of side rails 3.3 and a spacer expander 2 interposed between them to hold the side rails 3 and press them against the cylinder inner wall 4. The spacer expander 2 is formed into a radially corrugated shape, and has an inner convex portion 21 that contacts the inner circumferential side surface of the side rail 3 and has a protrusion spaced apart on the circumferential side surface of the spacer expander 2. A pad portion 26 is formed having an inner circumferential protrusion integrally continuous with the protrusion in the circumferential direction and separated from the connecting member.

The pad portion 26 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 outer circumferential surface 5 of the side rail 3 may be subjected to surface treatment such as hard chrome plating or nitriding treatment, if necessary.

FIG. 2 shows an outline of the spacer expander 2 of the present invention, and FIG. 3 shows a perspective view of a portion thereof. As shown in the figure, the spacer expander 2 is made of an annular wave-shaped flat plate as a whole, and 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 24. They are connected in a wavy shape in the circumferential direction. Each inner convex above.

Pad portions 26 extending in the axial and circumferential directions are provided at both upper and lower ends of the portion 21, and as described above, a pair of side rails are provided to engage with the pad portions 26.

In the present invention, as shown in FIG.
6a, and a connecting member 2 that is integrally connected to the protrusion in the circumferential direction.
4 by press punching or the like to form a pad portion 26.26 having inner circumferential protrusions 26b, 26b that protrude equally on both sides of the inner protrusion, and the outer protrusion 22.
upper and lower axial ends 25a, 25a, and outer peripheral protrusions 25b, 25b that are integrally connected to the upper and lower ends in the circumferential direction, are separated from the connecting member 24 by press punching, etc., and protrude equally on both sides of the outer convex part. A side rail pressure receiving part 25 having
．． 25 is formed. With this configuration, it is possible to increase the contact area between the inner periphery of the side rail and the spacer-expander, and the pressure receiving area between the side rail and the inner periphery of the side rail. It is possible to maintain followability and sufficient pressing force at all times, and it is possible to maintain an even surface pressure distribution on the upper and lower surfaces of the ring groove 61 of the piston due to the side rail, and to obtain a sufficient upper and lower surface sealing effect. , mwi
r Oil consumption can be reduced. Preferably, the pad portion 26 includes a protrusion 26a at the upper and lower ends of the inner protrusion and an inner peripheral protrusion 26b, and the upper and lower ends 25a of the outer protrusion and the protrusion 25.
As shown in FIG. 2, the side rail pressure receiving portion 25 consisting of b is formed so as to be located on the same circumference over the entire circumference of the spacer expander, thereby achieving a more even pressing force and upper and lower surface surface pressure distribution. This further improves the sealing effect.

In the conventional spacer expander shown in Fig. 4,
Its protrusion 21 around the entire circumference of the spacer expander
1 and the circumferential length of the pressure receiving surface 221 is 15 to 20 of the total circumferential length of the combined oil ring protrusion and pressure receiving surface
%, but in the pad portion and side rail pressure receiving portion of the present invention, it is set to at least 30% or more, making it possible to increase the contact area and pressure receiving area compared to conventional ones,
As described above, it is possible to prevent wear of the contact portion with the inner periphery of the side rail and undulation in the axial direction of the side rail during use, and to obtain an even surface pressure distribution. It can be freely set and drawn to the above length without being subject to shape restrictions as in the past.

Furthermore, as shown in FIG. 1, in the structure of the combination oil ring of the present invention, the spacer expander is separated from the connecting member and an inner circumferential protruding portion 26b and an outer circumferential protruding portion 25b are provided in the circumferential direction. ! 1241 is
It can serve as an oil distribution hole, and the process of punching out the oil distribution hole 23 as shown in FIG. 2 can be omitted, but depending on the model, a separate oil distribution hole may be provided. .

The extended length, axial width, etc. of the protruding portions of the pad portion 26 and the side rail pressure receiving portion 25 are determined in accordance with the strength of the spacer expander and other requirements. Furthermore, in the above embodiment of the spacer expander of the present invention, a case has been described in FIG. 3 in which the protruding portion protrudes from the upper and lower ends of the inner convex portion and the outer convex portion to both sides in the circumferential direction. A better effect than before can be obtained even if the convex portion and the outer convex portion are protruded from either the upper or lower ends or from the inner convex portion or the outer convex portion only on one side in the circumferential direction, but the embodiment shown in FIG. The one shown below is the most desirable and exhibits excellent effects.

<Effects of the Invention> As described above, the present invention provides a spacer expander with a pad portion and a side rail pressure receiving portion that can increase the contact area and pressure receiving area by several orders of magnitude compared to the conventional one, thereby making it possible to withstand harsh use in recent years. It can prevent the wear of the contact area with the inner circumference of the conventional side rail and the waviness in the axial direction of the side rail, which occurs under certain conditions, and achieves uniform radial and upper and lower surface pressure distributions, providing a sufficient sealing effect on the upper and lower surfaces. . Therefore, it is possible to reduce the amount of lubricating oil consumed, and the practical benefits of implementing this method are extremely large.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the combination oil ring of the present invention installed in the oil ring groove of the piston, Fig. 2 is a plan view of the spacer expander of the combination oil ring of Fig. 1, and Fig. 3 is the main FIG. 4 is a partially cutaway perspective view showing an embodiment of the invention; FIG. 4 is a partially cutaway perspective view of a spacer expander of a conventional combination oil ring; FIG. 5 is a conventional combination oil ring installed in an oil ring groove of a piston. FIG. The symbols in the diagram are: 1...Combination oil ring. 2...Spacer expander. 21...Inner convex portion. 22...Outside convex portion. 24...Connection member. 211... Protrusion. 25...Side rail pressure receiving part. 25a... Upper and lower ends of the outer convex portion in the axial direction. 25b...Outer peripheral protrusion. 26a...Protrusion 26b...Inner peripheral protrusion 3...Side rail. 4... Cylinder inner wall. 5... Inner and outer peripheral surfaces of the side rails. 6... Piston. are shown respectively.

Claims (4)

[Claims] (1) Consisting of a corrugated flat plate having an annular shape as a whole, the corrugation is provided with a series of outer protrusions and a series of inner protrusions alternately, and these protrusions are connected by a connecting member extending in the radial direction. A combination oil ring comprising a spacer expander having projections integrally provided at the upper and lower ends of the inner convex portion in the axial direction, and a pair of side rails disposed above and below the spacer expander, the spacer at least one of the protrusions at the upper and lower axial ends of the inner convex part of the expander; and an inner circumferential protrusion that is integrally connected to at least one of the protrusions in the circumferential direction and is separated from the connecting member. and an outer periphery which is integrally connected to at least one of the upper and lower ends in the circumferential direction and is separated from the connecting member. A combination oil ring characterized by forming a side rail pressure receiving part having a protruding part. (2) In the combination oil ring, a protrusion at the upper and lower axial ends of the inner convex portion of the spacer expander, and an inner peripheral protrusion that is integrally connected to the protrusion in the circumferential direction and separated from the connecting member. and a side rail pressure receiving part having upper and lower ends in the axial direction of the outer convex part, and an outer peripheral protrusion part that is integrally connected to the upper and lower ends in the circumferential direction and separated from the connecting member. The combination oil ring according to claim 1, characterized in that the combination oil ring is formed by: (3) In the combination oil ring, the inner circumference protrusion and the outer circumference protrusion protrude on both sides of the inner protrusion and the outer protrusion in the circumferential direction. Combination oil ring. (4) In the combination oil ring, the pad portion and the side rail pressure receiving portion are located on the same circumference over the entire circumference of the spacer expander. ring.