| CPC F16J 9/20 (2013.01) [F16J 9/062 (2013.01)] | 5 Claims |
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1. An oil control ring, comprising:
an oil ring having a pair of land parts arranged in a sliding direction and connected to each other by a web part; and
a coil expander arranged on an inner circumferential side of the oil ring in a radial direction, the coil expander biasing the oil ring toward an outer circumferential side in the radial direction,
wherein the web part of the oil ring is provided with a plurality of window holes along a circumferential direction, the window holes each extending through the web part in the radial direction;
wherein, in an axial cross-sectional view of a largest opening portion in an axial direction of the window hole in the oil ring, an inner surface of a combustion chamber-side land part which is located on the outer circumferential side in the radial direction of the combustion chamber-side land part and connects an outer circumferential surface in the radial direction of the web part and a sliding surface of the land part, and an inner surface of a crank case-side land part which is located on the outer circumferential side in the radial direction of the crank case-side land part and connects the outer circumferential surface in the radial direction of the web part and a sliding surface of the land part, are formed so as to increase a diameter toward the outer circumferential side in the radial direction, and
wherein, in the axial cross-sectional view of the largest opening portion of the window hole in the axial direction of the oil ring, a width H1 in the sliding direction of the oil ring and a length L1 of a combustion chamber-side non-window hole part, which excludes the window hole, in the outer circumferential surface of the web part, satisfy the following condition:
0.15>L1/H1≥0, wherein, in the axial cross-sectional view of the largest opening portion of the window hole in the axial direction of the oil ring, when a crank case-side end of the sliding surface of the combustion chamber-side land part is referred to as point A, a window hole-side end of the combustion chamber-side non-window hole part in the outer circumferential surface of the web part is referred to as point B, and an end of the combustion chamber-side non-window hole part, which is located on a side of the inner surface of the land part, in the outer circumference surface of the web part is referred to as point C, a distance AB between the points A and B, a distance AC between the points A and C, and a distance BC between the points B and C, satisfy the following condition: 1.0< (distance AC+distance BC)/(distance AB)≤1.5,
wherein, in the axial cross-sectional view of the largest opening portion of the window hole in the axial direction of the oil ring, an area of a triangle formed by the points A, B and Cis 11% or less and greater than 0% of an area of a space formed by the pair of land parts and the web part on the outer circumferential side in the radial direction of the oil ring, and
wherein, in the axial cross-sectional view of the largest opening portion of the window hole in the axial direction of the oil ring, an angle formed by a virtual line passing a crank case-side end of the sliding surface of the combustion chamber-side land part and the window hole-side end of the combustion chamber-side non-window hole part in the outer circumferential surface of the web part, with respect to the radial direction of the oil ring, is 33 degrees or less.
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