Tpr Co., Ltd.

Tpr Industry Co., Ltd.

Akira Hikone

Naoki Umeda

Hiroyuki Nagakura

Shuichi Inamori

Takashi Oguro

Takashi Inoue

Kiyoyuki Kawai

Takashi Ozawa

Akira Sato

Masami Horigome

Noriaki Ayuzawa

Takashi Oizumi

Yushi Abe

Masayuki Ohira

Toshihiro Yamaoka

An outer circumferential surface of a piston ring has a cut surface forming a notched portion between an outer circumferential end surface and a lower surface, the cut surface including a first surface between the outer circumferential end surface and a bottom portion, and a second surface between the bottom portion and the lower surface. The second surface is inclined away from a central axis of the piston ring as it extends toward a crank chamber side, an angle of inclination of the second surface with respect to the bottom portion being greater than or equal to 50° and less than or equal to 85°. When an axial width of the piston ring is hand a distance in an axial direction between a connecting portion between the cut surface and the outer circumferential end surface and a connecting portion between the cut surface and the lower surface is H, H/his greater than or equal to 0.2 and less than or equal to 0.4.

Piston ring

An outer peripheral surface of a compression ring includes a barrel curved surface, in a case where a width of the outer peripheral surface in an axial direction of the compression ring is set as L1, a condition of 0.2 mm≤½×L1 is satisfied, and in a case where a distance in a radial direction of the compression ring between an outer peripheral peak and each of two points on the barrel curved surface separate from the outer peripheral peak by 0.1 mm in the axial direction of the compression ring is set as d1, and a distance in the radial direction of the compression ring between the outer peripheral peak and each of two points on the barrel curved surface separate from the outer peripheral peak by ¼×L1 in the axial direction of the compression ring is set as d2, a condition of d1<d2 is satisfied.

Compression ring

An oil control ring comprises: 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 that biases the oil ring toward the outer circumferential side in the radial direction. The web part of the oil ring is provided with a plurality of window holes. 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 Hin the sliding direction of the oil ring and a length Lof a combustion chamber-side non-window hole part, which excludes the window hole, in the outer circumferential surface of the web part, satisfy the condition of 0.15>L/H

Oil control ring

A combination of piston rings assembled to a piston includes a first compression ring, a second compression ring, a third compression ring and an oil ring. When an axial width of the first compression ring is h1(1), an axial width of the second compression ring is h1(2), an axial width of the third compression ring is h1(3) and an axial width of the oil ring is h1(4), h1(1)≥h1(2) and h1(1)≥h1(3), and when h1(TOTAL)=h1(1)+h1(2)+h1(3)+h1(4), h1(TOTAL)≥3.9 mm.

Combination of piston rings, and combination structure of piston and piston rings

A combination of piston rings assembled to a piston of an internal combustion engine includes four compression rings. An outer peripheral surface of a first compression ring includes a barrel surface, an outer peripheral surface of a second compression ring includes an outer peripheral end portion and a taper surface, an outer peripheral surface of a third compression ring includes an outer peripheral end portion and a taper surface, and an outer peripheral surface of a fourth compression ring includes an outer peripheral end portion and a taper surface.

Piston ring combination, and internal combustion engine

A combination of piston rings assembled to a piston includes a first compression ring, a second compression ring, a third compression ring and an oil ring. When an axial width of the first compression ring is h1(1), an axial width of the second compression ring is h1(2), an axial width of the third compression ring is h1(3) and an axial width of the oil ring is h1(4), h1(1)≥h1(2) and h1(1)≥h1(3), and when h1(TOTAL)=h1(1)+h1(2)+h1(3)+h1(4), h1(TOTAL)≥3.1 mm.

Provided are a method of manufacturing an engine, an engine, and a connected cylinder. The method of manufacturing an engine includes at least a fitting step of fitting a connected cylinder to a hollow portion of a cylinder block main body. The connected cylinder is (1) a first connected cylinder including two or more cylinder liners and a connecting portion configured to connect the two or more cylinder liners to each other or (2) a second connected cylinder including a connected cylinder main body portion having two or more cylinder bores and a coating configured to cover an inner peripheral surface of the connected cylinder main body portion in which the cylinder bores are formed. The cylinder block main body has one end side, another end side, and the hollow portion passing through the cylinder block main body from the one end side to the another end side.

Growing community of inventors

Tokyo, Japan

Akira Hikone