Provided is a half bearing constituting a sliding bearing that is unlikely to cause damage during an operation of an internal combustion engine. The half bearing includes at least one protrusion, and the protrusion projects outward in a radial direction from an outer circumferential surface. A recessed portion that is recessed inward in the radial direction from the outer circumferential surface is formed over the entire inner-circumferential length between the protrusion and a circumferential-direction end surface of the half bearing. Two radial-direction grooves are formed in the circumferential-direction end surface of the half bearing relative to the protrusion, and each of the radial-direction grooves is adjacent to each of recessed portion side surfaces. The radial-direction grooves extend in the radial direction along the recessed portion side surfaces and are separated from the recessed portion at a midpoint of the extension. An inner circumferential surface-side end portion in an extending direction of the radial-direction grooves is located between a recessed portion bottom surface and an inner circumferential surface of the half bearing. A groove width and a groove depth of the radial-direction grooves decrease from the position separated from the recessed portion toward the inner circumferential surface-side end portion and reach zero at the inner circumferential surface-side end portion.

A half thrust bearing includes a slide surface which includes: at least two oil grooves extending in a radial direction; a plurality of pad surfaces located on both sides of each oil groove in a circumferential direction; and at least two first inclined surfaces each formed between the oil groove and the pad surface on a front side of the oil groove in a rotation direction of a crankshaft. A plurality of circumferential grooves are formed in succession in the radial direction on the first inclined surface. A plurality of oil drain grooves extends side by side to intersect the circumferential direction and the radial direction on the pad surface. A plurality of flat portions are formed each between the adjacent oil drain grooves. Each oil drain groove is open at a radially outer end and/or a radially inner end of the pad surface.

A half thrust bearing includes a slide surface which includes: at least two oil grooves extending in a radial direction; a plurality of pad surfaces located on both sides of each oil groove in a circumferential direction; and at least two first inclined surfaces each formed between the oil groove and the pad surface on a front side of the oil groove in a rotation direction of a crankshaft. A plurality of circumferential grooves are formed in succession in the radial direction on the first inclined surface. A plurality of oil drain grooves extends side by side to intersect the circumferential direction and the radial direction on the pad surface. A plurality of flat portions are formed each between the adjacent oil drain grooves. Each oil drain groove is open at a radially outer end and/or a radially inner end of the pad surface.

A cylinder block includes a support wall part that rotatably supports a crank shaft. The support wall part has a fitting recess part to which a bearing cap can be fitted. In each of the left and right corner parts where a bottom surface and a fitting surface of the fitting recess part intersect, a notch groove is formed that extends in the array direction of cylinder bores and has a substantially arc-shaped cross section when cut by the virtual plane along the extension direction thereof. As a result, stress having a greater value as the location becomes closer to the center part in the extension direction of the notch groove can be substantially uniform in the extension direction of said notch groove, and it is possible to effectively mitigate the stress concentration.

A cylinder block includes a support wall part that rotatably supports a crank shaft. The support wall part has a fitting recess part to which a bearing cap can be fitted. In each of the left and right corner parts where a bottom surface and a fitting surface of the fitting recess part intersect, a notch groove is formed that extends in the array direction of cylinder bores and has a substantially arc-shaped cross section when cut by the virtual plane along the extension direction thereof. As a result, stress having a greater value as the location becomes closer to the center part in the extension direction of the notch groove can be substantially uniform in the extension direction of said notch groove, and it is possible to effectively mitigate the stress concentration.

Provided is a technique capable of exhibiting high seizure resistance even if a scratch is formed. The sliding member of the present invention is a sliding member including a base layer and a resin coating layer formed on the base layer, wherein the resin coating layer is formed of a polyamide-imide resin as a binder, barium sulfate particles, molybdenum disulfide particles having an average particle diameter which is 1.0 time or more and 2.8 times or less the average particle diameter of the barium sulfate particles, and unavoidable impurities.

To provide a technique capable of realizing an appropriate wear resistance in a resin coating layer.

The sliding member of the present invention is a sliding member including a base layer and a resin coating layer formed on the base layer, wherein the resin coating layer is formed of a polyamide-imide resin as a binder, barium sulfate particles, molybdenum disulfide particles, and unavoidable impurities, wherein the resin coating layer is composed of a plurality of overcoated application layers, and wherein the plurality of application layers are different from each other in content of hard particles.

A bearing member 1 is provided with a coating layer 3 on an inner circumferential surface of a shaft hole 1A into which a shaft body 2 is to be fitted. The coating layer 3 is composed of a metal base material 3A and a heat conductive material 3B that is dispersed in the base material 3A and that has a thermal conductivity relatively higher than that of the base material 3A. The heat conductive material 3B has lengths Lb and Lc in directions B and C along a surface of the coating layer 3, longer than a length La in a thickness direction A of the coating layer 3, whereby thermal conductive characteristics in the directions B and C along the inner circumferential surface of the shaft hole 1A are enhanced. Thus, heat dissipation is improved, whereby temperature rise due to sliding contact with the shaft body 2 is suppressed, and seizure resistance is improved.

A cylinder block of an engine is provided. The cylinder block includes a cast body defining one or more cylindrical bores. The cylinder block also includes a crankshaft bearing wall formed within the cast body. The crankshaft bearing wall is configured to be removably coupled with a bearing cap to define an opening for rotatably supporting a crankshaft of the engine. The cylinder block further includes a chamfered shoulder portion casted on the crankshaft bearing wall.

A cylinder block of an engine is provided. The cylinder block includes a cast body defining one or more cylindrical bores. The cylinder block also includes a crankshaft bearing wall formed within the cast body. The crankshaft bearing wall is configured to be removably coupled with a bearing cap to define an opening for rotatably supporting a crankshaft of the engine. The cylinder block further includes a chamfered shoulder portion casted on the crankshaft bearing wall.