JPS5846661B2 - Steel combination oil ring side rail and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a sight rail for a steel combination oil ring for an internal combustion engine.

Recently, in order to improve the performance and economy of internal combustion engines, the site rail of the combination oil ring that is attached to the ring groove of the piston fitted in the cylinder is highly wear resistant and reduces the consumption of lubricating oil. Something is needed to reduce it.

As this wear-resistant material, there is generally a thermally sprayed layer formed by thermally spraying chrome plating or various other wear-resistant materials on the outer peripheral sliding surface of the sight rail.

A sight rail of a combination oil ring having a thermally sprayed layer of wear-resistant material on the outer sliding surface can be manufactured when the width is relatively large, but it is difficult to complete when the width is small. 0.05m sprayed layer on outer sliding surface
The situation is such that it cannot be put to practical use at all when more than m is required.

And the sight rail of the combination oil ring has a width of 0.
411! Although it is understood that if the sprayed layer is 0.05mm or more thick at m -0.8mm, the results will be good, but it has not yet been put to practical use. When the rail was removed from the rail, cracks and chips appeared on its side surface, and as a result, when it was installed as a piston sight rail, it caused scratches on the inner peripheral surface of the cylinder and the lubricating oil did not have a good scraping effect. It had some shortcomings.

In order to solve these problems, the present invention has a wear-resistant thermal sprayed layer of a constant thickness on the outer sliding surface of even the smallest sight rail, and also has a thermal sprayed layer on the outer peripheral sliding surface and the side surface. This invention relates to a method for manufacturing a sight rail for a steel combination oil ring, in which the outer circumferential chamfer angle formed between the upper and lower surfaces is appropriately ground and finished to enable the scraping action of lubricating oil and reduce its consumption. be.

Next, this will be explained with reference to the embodiment shown in the drawings.

First, as shown in FIG. 1, in the first step, both edges of the long relatively thin steel strip material 1 are made to form the inner and outer circumferential sides of the coil, and the outer circumferential side of the coil has a desired outer diameter a. The steel strip material is continuously wound spirally around the core 2 so that its side surfaces are in close contact with each other, and then rolled in the axial direction by the pressing plates 3 on both sides of the layer so as not to unwind. Pressure contact.

In the next second step, as shown in FIG. 2, the outer peripheral side edge of the steel strip material 1 spirally wound around the outer periphery of the layer 2 is heated to a predetermined diameter (cylinder diameter - 2 x sprayed layer thickness) a/. Copper strip material 1 that has been ground and spirally wound around wire 2 in the first step
The rounded shape of the outer periphery is removed to form a base processed surface 4 for a thermally sprayed layer of wear-resistant material to be thermally sprayed in the next third step.

Furthermore, in the third step, as shown in FIG. 3, a wear-resistant thermal spraying material such as ferrochrome powder, nickel self-fluxing alloy powder, molybdenum metal powder, etc. A thermal spray layer 5 is provided by thermal spraying a powder alone or a mixture of two or more of these powders, and then the wear-resistant thermal spray layer 5 is formed in a fourth step shown in FIG.
For example, the outer diameter is continuously ground 6 in the axial direction to a predetermined thickness to a slightly oversized diameter C, which is approximately the cylinder diameter plus post-process machining allowance.

Then, in the next fifth step, as shown in FIG. , the outer circumferential chamfer angle α that the outer circumferential side edge makes with its side surface
is ground by a screw grinding machine A having a V-shaped blade 7 with a tip angle of (2×α) to form a continuous sprayed layer 5 in the axial direction in a spiral shape as shown in FIG. 5. shall be separated.

As shown in the drawing, a sprayed layer is left on the outer circumferential surface of the spirally wound material by grinding and cutting it into a trapezoidal cross section with a screw grinder A having a V-shaped blade at the tip. The outer circumferential chamfer angle α between the outer circumferential side edge of the sprayed layer and the side surface (upper and lower surfaces) may also be, for example, 45° or less or more.

Next, in the sixth step, as shown in FIG. The site rail R is completed by cutting it in the axial direction (an axial guide groove is provided on the outer periphery of the rail) and removing it from the layer (Fig. 7), and then pulling it apart individually as shown in Fig. 8. It manufactures.

Conventionally, as shown in FIG. 9, the product that has gone through the first to fourth steps of the present invention is simply processed into the fifth step 90 of the present invention.
This was removed without going through the steps and directly cut in the axial direction of the blade with a cutting disc grindstone as in the sixth step of the present invention, but this was removed from the blade and further separated individually. When the oil ring is installed as a sight rail in the piston ring groove, cracks 10 and chips 11 occur in the thermal sprayed layer 5 made of wear-resistant material. This has caused drawbacks such as scratches and poor scraping action of the lubricating oil, but the present invention completely eliminates these problems.

In addition, the present invention produces sight rails by the method described above, so that the width thereof is extremely small, for example, 0.4 mm to 0.8 mm, and the thermal sprayed layer is approximately 0.05 m long.
A sight rail with a thickness of
The outer circumferential chamfering angle α between the upper and lower surfaces is ground with a tapered surface having an appropriate angle to form a trapezoidal shape, and an extremely good oil scraping property for lubricating oil can be obtained.

Furthermore, in another embodiment shown in FIG. 10, the product that has undergone the first to fourth steps of the present invention is
Part 1 to be commercialized as a sight rail in advance in the process
The V-shaped blade of the screw grinding machine A in the first embodiment is changed into a trapezoidal cross-section blade 7' to spirally cut off the thermal sprayed layer which has been previously ground into a part 1' to be discarded and an adjacent part 1' to be discarded. in,
Every other sight rail can be manufactured as a product, and the chamfer angle α can be precisely ground and formed.

In this case, of course, the same thin steel strip material may be continuously wound spirally to complete one thin copper strip material as a sight rail, and the other adjacent thin steel strip material may be discarded. As the thin steel strip material to be discarded, a low-quality and inexpensive material may be used in advance.

[Brief explanation of drawings]

1 to 6 show each manufacturing process of the method for manufacturing the sight rail of the present invention. FIG. 1 is a front view showing the first step, FIG. 2 is a front view showing the second step, and FIG. The figure is a front view with a partial cross section showing the third step, FIG. 4 is a front view with a partial cross section showing the fourth step, and FIG. Fig. 5 is a front view taken in cross-section at the − part showing the grinding relationship with the wound thin steel strip material;
The figure is a front view showing the 6th process, Figure 7 is a partially enlarged cross-sectional view showing the product made in the 6th process removed from the metal core, and Figure 8 is the one shown in Figure 7. FIG. 9 is a partially enlarged cross-sectional view of the sight rail completed by separating it into individual parts. FIG. The figure is a partially sectional front view of another embodiment. 1... Thin steel strip material, 2... Hiring (core metal)
, 3... Press plate, 4... Grinding surface, 5...
...Thermal sprayed layer made of wear-resistant material, 6...
Grinding surface, 1... V-shaped blade, 8... Trapezoidal sprayed layer, 9... Disc grindstone, A... Screw grinder.

Claims (1)

[Claims] 1. A first step in which the side edges of the long thin steel strip material are closely wound into a spiral so that the edges of the material become the inner and outer peripheries of the coil, and the outer periphery side edges of the spiral material are a second step of grinding; a third step of spraying a wear-resistant material on the outer peripheral side edge to form a continuous sprayed layer; and a fourth step of grinding the sprayed layer to a required thickness; On the outer circumferential surface of the ground thermal spray layer, at the boundary between the outer circumferential edges of the materials that are adjacent to each other at the same pitch as the spirally processed coil, an appropriate outer circumferential chamfering angle is formed between the outer circumferential edge and the side surface thereof. The fifth step is to continuously cut grooves of a predetermined depth in a spiral shape.
and a sixth step of cutting the spiral material and the continuous spiral sprayed layer on the outer peripheral side edge thereof in the longitudinal direction and separating them into individual parts. manufacturing method.