JPH0521652Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a spacer expander for a combination oil ring used in an internal combustion engine.

PRIOR ART

A combination oil ring usually has one side rail arranged on the upper and lower surfaces of one spacer expander, and the side rails are brought into sliding contact with the inner wall of the cylinder by the spacer expander to scrape up and scrape down lubricating oil. This is to ensure that an appropriate oil film is always formed on the cylinder inner wall to minimize wear on the piston ring and cylinder.

[Problem that the invention attempts to solve]

However, when trying to widen the abutment of such a spacer expander, insert it into the ring groove of the piston, abut the abutment of the spacer expander within the ring groove, and then assemble the side rails, the spacer expander may There may be cases where one of the abutments crosses over the other and the abutments overlap.

When assembled to the piston in such a state, tension cannot be applied to the side rail and the spacer expander does not function.

The present invention aims to prevent such problems and improve the spacer expander so that it can be properly assembled to the piston.

[Means for solving problems]

The structure of the present invention that achieves the above-mentioned problems is that, in a spacer expander having a gap continuous in the circumferential direction and opening laterally, coil springs are installed in the gaps on both joint opening sides of the spacer expander. A guide rod is fixed along the circumferential direction of the coil springs and inserted through the coil springs, and is disposed astride both joint openings.

[Effect]

The guide rod is attached to both sides of the gap of the spacer expander, which is continuous in the circumferential direction of the spacer expander and opens to the side, by inserting it through the coil spring fixed along the circumferential direction in the gap, and when the spacer expander is assembled into the piston ring groove and the gap of the spacer expander is expanded, the through hole of the coil spring fixed to the spacer expander slides along the guide rod, and the gap is always guided by the guide rod and expanded. Then, when the gap of the spacer expander is closed after being inserted into the piston ring groove, as described above, the through hole of the coil spring fixed to the spacer expander slides along the guide rod, and the gap is always guided by the guide rod, and the spacer expander returns to the original state with the gap closed without overlapping.

〔Example〕

Fig. 1 is a partially sectional plan view showing the vicinity of the abutment of the spacer expander equipped with a coil spring and guide rod, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig. 3 is a - line sectional view in Fig. 1. FIG. 4 is a cross-sectional view, and FIG.
The figure is a front view of the coil spring, Figure 6 is a side view of Figure 5, Figure 7 is a plan view of the guide rod, and Figure 8 is a cross-sectional view of the ring groove portion of the piston incorporating the spacer expander and side rail. It is.

In FIG. 1, a spacer expander 1 has a pair of upper and lower pieces 2 and 3 extending in the circumferential direction, which are spaced apart from each other in the vertical direction, their outer peripheral ends are connected by a connecting piece 4, and the inner peripheral The ends are provided with side rail pressing pieces 5 and 6 that stand up outward, and the axial cross section is approximately U-shaped. A large number of oil holes 7 are formed at equal intervals in the circumferential direction from the upper piece 2 to the lower piece 3, and from the upper side rail pressing piece 5 to the upper piece 2, and from the lower side rail pressing piece 6 to the lower part. On the piece 3, a large number of V-shaped notches 8a and 8b are formed between the oil holes 7.

Coil springs 9 and 10 are attached to both abutment openings 11 and 12 sides of spacer expander 1, respectively. The outer diameters of these coil springs 9 and 10 are slightly larger than the dimension between the lower surface of the upper piece 2 and the upper surface of the lower piece 3, and the lengths are the abutments 11 and 10, respectively, when attached to the spacer expander 1. 12
It has a dimension from the position to a position near the front of the second oil hole 7. Then, the coil spring 9 is press-fitted between the upper piece 2 and the lower piece 3 from the opening on the inner peripheral side of the spacer expander 1, and the coil spring 9 is press-fitted between the upper piece 2 and the lower piece 3.
It is attached along the circumferential direction of the spacer expander 1 between the upper piece 2 and the lower piece 3 over a position near the second oil hole 7 from the position. Therefore, in the installed state, as shown in FIG.
The coil spring 9 disposed between the upper piece 2 and the lower piece 3 other than the oil hole 7 has a deformed elliptical cross section and is press-fitted between the upper piece 2 and the lower piece 3, and is inserted into the oil hole 7. Then, as shown in FIG. 2, they are arranged in a perfect circular shape in a free state. Therefore,
As can be understood from FIGS. 1 to 4, the coil spring 9 of the oil hole 7 is engaged with the radial cut end surfaces 13 and 14 of the upper piece 2 and the lower piece 3, and The circumferential cut end surfaces 15 of the upper piece 2 and the lower piece 3 do not protrude from the opening,
16 and is also prevented from moving in the circumferential direction. In this way, the coil spring 9 is attached to one side of the abutment 11 of the spacer expander 1. A coil spring 10 is similarly attached to the other abutment 12 side.

The guide rod 17 is a curved round rod with a circular cross section and approximately the same curvature as the spacer expander 1; however, its cross section is not limited to the circular shape; The more you have, the better. The guide rod 17 is inserted into the through holes of the coil springs 9 and 10 installed on the sides of the abutments 11 and 12 of the spacer expander 1, and is attached to the spacer expander 1 while straddling the abutments 11 and 12. It will be installed. Both ends of this guide rod 17 are made flat by press working,
These flat parts 18 and 19 are locked to the coil springs 9 and 10, and the coil springs 9 and 10
It is configured so that it cannot be removed. In this case, in actual work, the flat parts 18, 1
A pair of coil springs 9 and 10 are passed through a round bar without 9, and then flat parts 18 and 10 are attached to both ends.
19 are provided, and these are mounted on the spacer expander 1.

Therefore, as shown in FIG.
If the coil springs 9, 10 and guide rod 17 are attached to the spacer expander 1 as described above before assembling the spacer expander 1 into the piston ring groove 21, the abutment 11 of the spacer expander 1, When expanding 12,
The through holes of the coil springs 9 and 10 fixed to the spacer expander 1 slide along the guide rod 17, and the abutments 11 and 12 are always connected to the guide rod 17.
It spreads under the guidance of and piston ring groove 2
1, when the abutments 11 and 12 of the spacer expander 1 are closed, the coil springs 9 and
The ten through holes slide along the guide rod 17, the abutments 11 and 12 are always guided by the guide rod 17, and the spacer expander 1 returns to its original state with the abutments closed without the abutments 11 and 12 overlapping. .

In FIG. 8, 22 and 23 are side rails disposed on the upper and lower surfaces of the spacer expander 1, and 24 is a cylinder.

In the above example, flat portions 18 and 19 were provided at both ends of the guide rod 17 as locking portions for the coil springs 9 and 10, but the locking portions are not limited to these, and other locking portions, such as those shown in FIG. Bent parts 25 and 26 may be provided as shown in FIG. 10, burrs 27 and 28 caused by shearing may be provided as shown in FIG.
As shown in FIG. 12, heat-resistant heat-shrinkable tubes 31 and 32 may be fixed, or a piece of soft metal such as lead, tin, or solder may be fixed. Further, in the above example, the locking portions 18 and 19 are provided at both ends of the guide rod 17, but the locking portion 33 may be provided at the center of the guide rod 17 as shown in FIG. In addition, although the illustrated one forms the locking part 33 by bending, the locking part 33 is not limited to this, and as mentioned above, it may be formed by bending the locking part 33.
It may be formed by forming a flat portion, or by fixing a heat-resistant resin, a heat-resistant heat-shrinkable tube, or a piece of soft metal.

Further, in the above example, the guide rod 17 is connected to both joint openings 11,
The spacer expander 1 was long enough to span the spacer expander 12 and be placed on a part of the entire circumference of the spacer expander 1, but
As shown in FIG. 14, a guide rod 17 having a length extending substantially over the entire circumference of the spacer expander 1 (preferably two-thirds or more of the entire circumference) may be used.
The one shown has a bent locking part 2 at one end.
5a, but coil springs 9, 10
It is not necessary to provide a locking part with the. In that case, it is preferable that both ends of the guide rod 17 be placed at positions 180 degrees opposite to the abutments 11 and 12.

In addition, the coil springs 9 and 10 have an outer diameter that is approximately equal to the dimension between the lower surface of the upper piece 2 and the upper surface of the lower piece 3, and the outer circumferences of the coil springs 9 and 10 are welded or It may be fixed by being bonded to the spacer expander 1 with an adhesive or the like. Also, as shown in Figure 15,
The coil springs 9 and 10 can also be fixed by assembling an annular elastic body 34, a tube, a pipe, or the like on the inner circumferential side of the spacer expander 1.

16 to 18 show a spacer expander having a different cross-sectional shape from the spacer expander 1 described above, and includes coil springs 9,
10 and guide rod 17 are the same as those described above. Figure 16 shows upper piece 2 and lower piece 3.
is provided with inclined piece parts 2a and 3a at the connection part with the connecting piece 4 (in the above spacer expander 1, the upper piece 2 and the lower piece 3 are not provided with the inclined piece parts, and are arranged horizontally). eggplant). In FIG. 17, a connecting piece 4 is provided at the inner peripheral end of the upper piece 2 and the lower piece 3, and this connecting piece 4 protrudes in the vertical direction than the upper piece 2 and the lower piece 3, and this protruding piece allows the side Rail pressing piece 5,
6 was formed. In FIG. 18, the side rail pressing piece 6 is not provided on the lower piece 3 of the spacer expander 1, and the inner peripheral end of the lower piece 3 is reversely bent to form a side rail portion 35 extending parallel to the lower piece 3. It is.

19-20 show a radially corrugated spacer expander in which an outer top piece 36 and an inner bottom piece 37 are radially spaced apart and alternately arranged in the circumferential direction, and It consists of radially corrugated strips connected by intermediate pieces 38. Then, the outer top piece 3 straddles the adjacent intermediate piece 38.
An oil hole 39 is formed on the 6 side, and the spacer expander 1 straddles the adjacent intermediate piece 38.
Coil springs 9 and 10 are mounted on both abutment openings 11 and 12 along the circumferential direction in a gap that continues in the circumferential direction and opens laterally. Since the outer diameter of the coil spring is larger than the vertical width of the oil hole 39, the coil spring has an outer top piece 36 and an inner bottom piece 37 in the radial direction.
The intermediate piece 3 is locked in the circumferential direction and does not come out.
8 and is prevented from moving and fixed to the spacer expander 1.

FIG. 21 shows an oil ring 40 having a U-shaped cross section, and similarly to the above, coil springs 9, 1
0 on both joint openings 11 and 12 side, and guide rod 17
Insert the coil springs 9 and 10 into both joints 1
1 and 12.

[Effect of idea]

As explained above, according to the present invention, when assembling the spacer expander into the piston ring groove, it is possible to reliably prevent one of the abutments of the spacer expander from climbing over the other and overlapping the abutments.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a partially sectional plan view showing the vicinity of the abutment of a spacer expander equipped with a coil spring and a guide rod; FIG. 2 is a sectional view taken along the line -- in FIG. 1; Figure 3 is a sectional view taken along the - line in Figure 1, Figure 4 is a perspective view showing the vicinity of the abutment of the spacer expander equipped with a coil spring and guide rod, Figure 5 is a front view of the coil spring, and Figure 6 is a side view of Fig. 5, Fig. 7 is a plan view of the guide rod, Fig. 8 is a sectional view of the ring groove portion of the piston incorporating the spacer expander and side rail, and Figs. 9 to 13 are views of the engagement of the guide rod. FIG. 14 is a plan view of a guide rod showing another example of a stop portion; FIG. 14 is a plan view of another example of a guide rod; FIG. 15 is a sectional view of a spacer expander showing another example of fixing a coil spring; 16 to 18 are sectional views corresponding to FIG. 8 of another spacer expander having different axial cross-sectional shapes, FIG. 19 is a sectional view corresponding to FIG. 8 of a radially corrugated spacer expander, and FIG. The figure is a plan view of the spacer expander part.
FIG. 21 is a sectional view of the oil ring corresponding to FIG. 8. 1 is a spacer expander, 2 is an upper piece, 3 is a lower piece, 4 is a connecting piece, 5 and 6 are side rail pressing pieces, 7 and 39 are oil holes, 8 is a notch, 9,
10 is a coil spring, 11 and 12 are abutments, 1
7 is a guide rod, 18, 19, 25, 26, 27,
28, 29, 30, 31, 32, 33 are locking parts;
20 is a piston, 21 is a piston ring groove, 2
2, 23 are side rails, 24 is a cylinder, 34
35 is an elastic body, 35 is a side rail portion, 36 is an outer top piece, 37 is an inner bottom piece, and 38 is an intermediate piece.

Claims (1)

[Scope of utility model registration request] In a spacer expander having a gap continuous in the circumferential direction and opened laterally, a coil spring is fixed along the circumferential direction in the gap on both abutment sides of the spacer expander,
A structure for preventing overlapping of abutments of a spacer expander, characterized in that a guide rod that is inserted through the coil springs is disposed astride both abutments.