JPH0152576B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to piston rings used in internal combustion engines, particularly to a combination oil-scraped piston ring.

[Background of the invention]

Combination oil-scraped piston rings, which usually consist of one spacer expander and a pair of side rails arranged above and below the spacer expander, are widely used. The present invention relates to a spacer expander for this combination oil-scraped piston ring.

[Conventional technology and its problems]

There are many types of spacer expanders for combination oil scraping piston rings, but they scrape off excess lubricating oil on the cylinder inner wall and return it to the oil pan, while leaving an appropriate lubricating oil film on the cylinder inner wall to prevent wear of the piston ring and cylinder. The spacer expander shown below is widely used as one that fully satisfies the original functions of oil-scraped piston rings, such as reducing the amount of lubricating oil and sealing so that excess lubricating oil does not enter the combustion chamber. ing.

That is, the spacer expander is composed of a corrugated band plate in which the outer top sides and the inner top sides are arranged alternately in the longitudinal direction, and the side edges are integrally interposed between them.
It is widely known as No. 10104.

Although this spacer expander had excellent performance, it had the following drawbacks.

That is, when fitting a spacer expander into a piston ring structure provided on a piston, the abutment of the spacer expander is widened and inserted into the piston ring groove, and the abutment of the spacer expander is butted within the piston ring groove. However, in some cases, the joints may overlap and be fitted. Also, after the spacer expander is fitted into the piston ring groove, the side rails are sometimes assembled, but when trying to assemble the side rails, one of the joints may cross over the other and the joints may overlap. .

If it were to be fitted into the piston ring groove and further assembled into the cylinder in such a state, it would naturally not be able to apply any tension to the side rails and would lose its function as a spacer expander.

Therefore, when putting this type of spacer expander into use, it is necessary to take countermeasures against the above defects, and many improvements have been made.

A spacer expander that prevents the overlapping of the abutment portions is disclosed in Japanese Patent Publication No. 48884/1984. As shown in FIG. 8, this spacer expander has an abutment G of a wave-shaped spacer expander S in which the outer top sides 5 and the inner top sides 6 are arranged alternately in the longitudinal direction, and the top sides 4 are integrally interposed therebetween. A small through hole 3 is provided on the nearby side 4 through which the stopper piece 21 bent at both ends of the guide rod 2 cannot pass through. A large through hole 31 is provided through which the locking piece 21 can pass through, and the guide rod 2 is passed through the through holes 3, 31, so that the locking piece 21 of the guide rod 2 is attached to the periphery of the through hole 3 of the spacer expander S. The abutments are locked and guided by the guide rod 2 through the through hole 3 to prevent the abutments from overlapping.

However, this spacer expander
When the guide rod is made of synthetic resin, the locking piece can be easily formed using thermal deformation, but when the guide rod is made of metal, there is a defect in the shape of the locking piece that makes it difficult. Furthermore, in the case of a guide rod made of synthetic resin, it is good if the width of the spacer expander is large, but if it is small, a wire rod with a small diameter is used, which causes problems in terms of rigidity and lacks the function as a guide rod. For this reason, in the case of a spacer expander with a small width, it is necessary to rely on a metal guide rod, but as mentioned above, in the case of a metal guide rod, it is difficult to form the stop pieces at both ends, so it is not practical. was difficult.

In addition, as a spacer expander that uses a different method to prevent overlapping of the abutments,
There is one shown in No. 47131.

As shown in FIG. 9, this spacer expander S is a wave-shaped spacer expander S in which outer top sides 5 and inner top sides 6 are arranged alternately in the longitudinal direction, and side sides 4 are integrally interposed therebetween. abutment G
A through hole 3 is provided on the side 4 near the outer top edge 5 or the inner edge 6, and the through hole 3 is further biased toward the outer edge 5 or the inner edge 6.
adjacent to the side 4 from the outer top edge 5 to the inner top edge 6
A through hole 31 large enough to span the length of the metal guide rod 7 is provided, and the metal guide rod 7 passes through the through hole 31. A trapezoidal space 8 is formed by the outer apex 5 or the inner apex 6 and the sides 4 on both sides, or
In the trapezoidal space 8 on only one side of the abutment, the end of the guide rod 7 is bent to form a depression 71,
The recessed portion 71 of the guide rod 7 is engaged with the periphery of the through hole 3 of the spacer expander S.

With this spacer expander, even when using a small-diameter metal guide rod as the guide rod 7 with the spacer expander S having a small width, it is easy to bend the recessed portion 71 and prevent overlapping of the abutment portion. has become possible and is now widely used.

However, when manufacturing this spacer expander, although it is easy to bend the end of the guide rod within the trapezoidal space, it requires caulking, so manufacturing using a special machine is required. It is very difficult to automate time.

[Purpose of the invention]

The present invention aims to solve the above-mentioned conventional problems, and aims to provide a spacer expander that can be manufactured extremely efficiently and has a means for preventing overlap of the abutments of radially corrugated spacer expanders. It is something.

[Means for solving problems]

In order to solve the above problems, the present invention has outer apex sides and inner apex sides arranged alternately in the longitudinal direction,
It consists of an annular corrugated band plate with side edges integrally interposed therebetween, and protrusions are provided on both sides of the inner top side integrally with this, and protrusions are provided integrally with both sides of the outside top side. In the spacer expander provided with a pressure receiving surface, a through hole is provided on each side near the abutment of the spacer expander, and a guide rod is inserted into the through hole so as to span the abutment, Furthermore, there is provided a spacer expander in which a guide rod stopper means is provided on either the inner top side or the outer top side of the side near both ends of the guide rod when the abutment of the spacer expander is closed.

The guide rod stopper means is a piece attached to the side where the through hole is not provided, the inner top side, or the outer top side.

[Effect]

As mentioned above, a through hole is provided on each side near the abutment of the spacer expander, and a guide rod is inserted into the through hole so as to straddle the abutment.
Furthermore, when the abutment of the spacer expander is closed, the sides near both ends of the guide rod;
Since a stopper means is provided on either the inner top side or the outer top side, the guide rod cannot be moved beyond the abutment portion.

Therefore, when the abutment of the spacer expander is elastically expanded when the spacer expander is fitted into the piston ring groove, the through hole of the spacer expander slides on the outer periphery of the guide rod.
In this way, the abutment of the spacer expander expands while being guided by the guide rod, and the guide rod straddles the expanded abutment.

Therefore, after expanding the abutment of the spacer expander and installing it in the piston ring groove, the abutment is guided by the guide rod again and elastically returns to the original closed state, ensuring that the abutment parts overlap. This will be prevented.

Also, when fitting a pair of side rails after fitting the spacer expander into the piston ring groove, the guide rod is inserted across the abutment of the spacer expander, so the abutment does not work as before. This will surely prevent one side from climbing over the other and causing the abutments to overlap.

〔Example〕

Embodiments of the spacer expander of the present invention will be described in detail with reference to the accompanying drawings. In addition, the 8th,
In FIG. 9, the same parts as those explained in the explained prior art are given the same reference numerals.

First, as shown in FIG. 2, the spacer expander is made of a ring-shaped corrugated band plate in which outer top sides 5 and inner top sides 6 are arranged alternately in the longitudinal direction, and side edges 4 are interposed between them. , protrusions 61 are provided on both sides of the inner top side 6 integrally with the inner top side 6, and pressure receiving surfaces 51 are provided on both side edges of the outside top side 5 integrally with the outside top side 5. A through hole 3 is provided on each side 4 near the abutment G of the spacer expander S having such a configuration.

As shown in FIG. 3, a guide rod 9 made of metal such as steel or stainless steel or synthetic resin such as tetrafluoroethylene resin or ABS resin is inserted into this through hole 3 as shown in FIG. It is inserted so that it straddles the. As the through hole 3, a hole conventionally provided on the side of the spacer expander can be used as it is as an oil window of the spacer expander.

Furthermore, in a state where the abutment G is closed, the through hole 3 is located near both ends 91, 91 of the guide rod 9.
A guide bar stopper member 10 is provided, which has a side 4 having no edges. The guide rod stopper member 10 consisting of the side 4 without the through hole 3 can be formed extremely easily since it can be formed in a press step during the manufacturing process of the spacer expander. Since the guide rod stopper member 10 is formed, the guide rod 9 is reliably prevented from moving beyond the guide rod stopper member 10 from the abutment portion G.

As the guide rod stopper means, as shown in FIG. 4, a piece 11 made of synthetic resin or metal may be attached to the inner top side 6 or the outer top side 5 by bonding or welding.

Since the spacer expander of the present invention has the above configuration, it operates as follows when the spacer expander is fitted into the piston ring groove.

FIG. 5 shows a cross-sectional view of the spacer expander S of the present invention in use in combination with a pair of side rails 12, fitted into a piston ring groove 14 provided in a piston 13, and further inserted into a cylinder 16. This is to make the following explanation easier to understand.

First, place the spacer expander S on piston 1.
When the spacer expander is fitted into the piston ring groove 14 provided in the piston ring groove 14, when the abutment G of the spacer expander is expanded, the through hole 3 slides on the outer periphery of the guide rod 9 and is guided to the guide rod 9 as shown in FIG. The abutment G will be widened. (Normally, in the case of a spacer expander for automobiles, the abutment is
It will be widened by about 40mm. ) The guide rod 9 is placed astride the widened abutment G. In the case of FIG. 6, the left and right sides of the abutment G of the spacer expander S slide approximately evenly on the outer circumference of the guide rod 9, but the guide rod 9 is loosely fitted into the through hole 3. Since it is inserted in this state, it not only always slides almost evenly as shown in FIG. 6, but also sometimes slides unevenly. For example, as shown in FIG. 7, it is conceivable that the through hole 3 on the right side of the abutment does not slide on the outer periphery of the guide rod 9 at all, and only the through hole 3 on the left side slides on the outer periphery of the guide rod 9. Therefore, the length of the guide rod 9 is the length from the guide rod stopper member 10 to the abutting piece 15 of the abutment G.
l1, the abutment widening amount l2 set depending on the model, and the length l3 that straddles the other abutment (to ensure smooth return when closing the abutment, it engages at least 3 through holes 3. ) is the minimum required length.

As mentioned above, since the guide rod 9 is spread out across the abutment, the piston ring groove 14
After being fitted into the spacer, the spacer expander is guided by the guide rod 9 and can smoothly and elastically return to the original state where the abutment is closed, thereby reliably preventing the abutment portions from overlapping. At this time, in order to smoothly return the abutment to its original closed state, it is desirable that the guide rod 9 has approximately the same curvature as the spacer expander 3, as shown in FIG.

Next, the upper and lower pair of side rails 12, 12 of the spacer expander S are fitted, but even at this time, the guide rod 9 is inserted across the abutment G of the spacer expander. Therefore, it is possible to reliably prevent one of the abutments from overlapping the other, which is the case in the past.

〔Effect of the invention〕

As explained above, the spacer expander of the present invention is provided with through holes on each side near the abutment, and a guide rod is inserted into the through hole so as to extend across the abutment. When the abutment is closed, the guide rod is a spacer expander in which a guide rod stopper means is provided on either the side, the inner top edge, or the outer apex near both ends of the guide rod. It is possible to reliably prevent the abutment portions from overlapping each other without moving beyond the guide rod stopper means.

In addition, the guide rod is simply inserted into the through hole, and unlike conventional guide rods, there is no need to deform both ends to create a locking piece, or to swage the guide rod, which would cause one part of the guide rod to cave in. , which has the effect of being able to be manufactured extremely efficiently.

Furthermore, in the spacer expander of the present invention, the guide rod can be made of either metal or synthetic resin, so it has the advantage that it can be manufactured from small widths to large widths.

[Brief explanation of drawings]

Fig. 1 shows an embodiment of the spacer expander of the present invention, and is a perspective view of only the abutment part with the abutment closed, and Fig. 2 shows the spacer expander of Fig. 1 in a state before the guide rod is inserted. FIG. 3 is a perspective view of only the guide rod shown in FIG. 1; FIG. 4 is a perspective view of the abutment with the abutment closed, showing another embodiment of the spacer expander of the present invention. FIG. 5 is a sectional view showing the state in which the spacer expander of the present invention is fitted into the piston ring groove, and FIGS. 6 and 7 are a partial perspective view of the spacer expander of the present invention shown in FIG. 1. Perspective view showing the state when the abutment of the spacer expander is opened, No. 8
FIG. 9 shows a perspective view of a conventional spacer expander. In the figure, S...Spacer expander, G...Abutment, 3...Through hole, 4...Side edge, 5...Outside top edge, 6...
Inner top side, 9... Guide rod, 10... Guide rod stopper member, 11... Piece piece, 12... Side rail, 15... Abutment piece, 51... Pressure receiving surface, 61...
protrusion.

Claims (1)

[Scope of Claims] 1 Consisting of an annular corrugated band plate with outer top sides and inner top sides arranged alternately in the longitudinal direction and side edges interposed therebetween, and on both side edges of the inner top side. In a spacer expander in which a protrusion is integrally provided and a pressure receiving surface is integrally provided on both edges of the outer top side, a through hole is provided on each side near the abutment of the spacer expander. A guide rod is inserted into the through hole, spanning the abutment, and when the abutment of the spacer expander is closed, any of the side, inner top, and outer top sides of the guide rod near both ends is inserted. A spacer expander characterized in that a guide rod stopper means is provided. 2. The spacer expander according to claim 1, wherein the guide rod stopper means is a side without a through hole. 3. The spacer expander according to claim 1, wherein the guide rod stopper means is a piece attached to the inner top side. 4. The spacer expander according to claim 1, wherein the guide rod stopper means is a piece attached to the outer top side. 5. "Claims 1 to 4" characterized in that the guide rod is a guide rod having substantially the same curvature as the curvature of the spacer expander.
spacer expander.