Abstract: An internal combustion engine oil ring which stably retains, for a long period, the function of scraping excess oil from a cylinder inner wall surface and letting the excess oil flow down to an underside of a piston and ensures reduction in the amount of oil consumption when an internal combustion engine is driven. An internal combustion engine oil ring is provided, whose main body includes, along an inner peripheral surface, a coil expander receiving recess having a generally semicircular shape in cross-section in an oil ring axial direction, an inner peripheral surface of the coil expander receiving recess has an oil return groove formed along an inner peripheral direction for smoothly returning scraped oil to an underside of a piston, and an outer peripheral shape of the groove is composed of a straight line and a curved line continuous therewith in cross-section in the oil ring axial direction.

Abstract: An oil ring for an internal combustion engine capable of securing an area of an oil-passing hole without deteriorating the strength of the oil ring. To achieve this the oil ring is provided with an oil-passing hole including: two arc portions disposed at both ends in circumferential direction, so as to be opposed to each other; two parallel straight portions disposed so that a widthwise direction distance therebetween is longer than a width of the arc portion; and inclined portions for connecting the arc portions and the parallel straight portions to each other.

Abstract: An oil ring for an internal combustion engine capable of securing an area of an oil-passing hole without deteriorating the strength of the oil ring. To achieve this the oil ring is provided with an oil-passing hole including: two arc portions disposed at both ends in circumferential direction, so as to be opposed to each other; two parallel straight portions disposed so that a widthwise direction distance therebetween is longer than a width of the arc portion; and inclined portions for connecting the arc portions and the parallel straight portions to each other.

Abstract: It is a main object of the present invention to provide an oil ring which is capable of reducing sliding friction even in a high speed revolution region of a piston, and capable of reducing the consumption of oil.

Abstract: A main object of the present invention is to provide a combined oil ring capable of exhibiting a sufficient tension, having excellent oil scraping function and oil control function, even if a coil expander formed of a shape memory alloy is used. To achieve the above mentioned object, the present invention provides a combined oil ring comprising: an oil ring formed into cross-section substantially of an I-shape that two rails are connected at a columnar portion thereof; and a coil expander, which is placed in an inner peripheral groove formed on the inner side of a periphery of the columnar portion connecting the two rails of the oil ring, and which presses the oil ring radially outward, wherein the coil expander is formed of a shape memory alloy, and is formed of anomaly wire having rectangular cross sectional shape.

Abstract: It is a main object of the present invention to provide an oil ring which is capable of reducing sliding friction even in a high speed revolution region of a piston, and capable of reducing the consumption of oil.

Abstract: In the present invention, the thermal efficiency and concentration of a thermal head on a transfer film over the surface of a transfer drum are improved, thereby improving the reproducibility of gradation in printing, which enables highly minute transfer images to be printed on the transfer film. This makes it possible to form a highly minute image on an image-transferred member. To do this, a cushion layer made of elastomer and a rigid layer with a surface finish of less than 2.0 .mu.m on a surface of the cushion layer are provided on a surface of the drum base of the transfer drum.