Abstract: A semi-cylindrical half bearing for a sliding bearing includes at least one axial groove formed on its inner circumferential surface that includes a smooth groove surface formed back away from the inner circumferential surface toward a radially outer side of the half bearing. The groove surface forms a convex curve toward the radially outer side in a cross-section perpendicular to the axial direction of the half bearing, and forms a straight line extending in the axial direction in a cross-section parallel to the axial direction. The half bearing further includes a plurality of axial narrow grooves formed on the groove surface so as to be back away from the groove surface toward the radially outer side, that extend in the axial direction of the half bearing.

Abstract: A semi-cylindrical half bearing for a sliding bearing includes at least one axial groove formed on its inner circumferential surface that includes a smooth groove surface formed back away from the inner circumferential surface toward a radially outer side. The half bearing further includes a plurality of axial narrow grooves and a plurality of circumferential narrow grooves that are formed further back away from the groove surface toward the radially outer side, and extend in circumferential and axial directions, respectively, so as to cross each other. A depth of the axial narrow groove from the groove surface is greater than a depth of the circumferential narrow groove from the groove surface, and a width of the axial narrow groove on the groove surface is greater than a width of the circumferential narrow groove on the groove surface.

Abstract: A semi-cylindrical half bearing for a sliding bearing includes at least one axial groove formed on its inner circumferential surface that includes a smooth groove surface formed back away from the inner circumferential surface toward a radially outer side. The half bearing further includes a plurality of axial narrow grooves and a plurality of circumferential narrow grooves that are formed further back away from the groove surface toward the radially outer side, and extend in circumferential and axial directions, respectively, so as to cross each other. A depth of the axial narrow groove from the groove surface is greater than a depth of the circumferential narrow groove from the groove surface, and a width of the axial narrow groove on the groove surface is greater than a width of the circumferential narrow groove on the groove surface.

Abstract: A semi-cylindrical half bearing for a sliding bearing includes at least one axial groove formed on its inner circumferential surface that includes a smooth groove surface formed back away from the inner circumferential surface toward a radially outer side of the half bearing. The groove surface forms a convex curve toward the radially outer side in a cross-section perpendicular to the axial direction of the half bearing, and forms a straight line extending in the axial direction in a cross-section parallel to the axial direction. The half bearing further includes a plurality of axial narrow grooves formed on the groove surface so as to be back away from the groove surface toward the radially outer side, that extend in the axial direction of the half bearing.

Abstract: Provided is a semi-annular shaped half thrust bearing. The half thrust bearing has a sliding surface and a back surface opposite to the sliding surface. The sliding surface includes a plurality of recesses. Each recess has a recess surface recessed from the sliding surface toward the back surface. The recess surface is convex toward the back surface in cross-sectional view in a center line direction of the half thrust bearing. The recess surface includes a plurality of grooves. The grooves are recessed from the recess surface toward the back surface. The grooves extend in the center line direction so that smooth surfaces and the grooves are alternately arranged on the recess surface in a horizontal direction of the half thrust bearing.

Abstract: Provided is a semi-cylindrical shaped half bearing. The half bearing has an inner surface forming a sliding surface. The sliding surface includes a plurality of recesses. Each recess has a smooth recess surface recessed from the sliding surface toward an outer diameter side of the half bearing. The recess surface forms a convex curve toward the outer diameter side of the half bearing in a cross-sectional view in any direction perpendicular to the sliding surface. The recess surface includes a plurality of circumferential grooves. The circumferential grooves are recessed from the recess surface toward the outer diameter side of the half bearing. The circumferential grooves extend along a circumferential direction of the half bearing so that smooth surfaces and the circumferential grooves are alternately arranged on the recess surface.

Abstract: Provided is a semi-annular-shaped half thrust bearing having a sliding surface for receiving an axial force and a back surface opposite to the sliding surface. The sliding surface includes a plurality of recesses. Each recess has a recess surface recessed from the sliding surface toward the back surface of the half thrust bearing. The recess surface is convex toward the back surface of the half thrust bearing in cross-sectional view in a circumferential direction of the half thrust bearing. The recess surface includes a plurality of circumferential grooves recessed from the recess surface toward the back surface of the half thrust bearing. The circumferential grooves extend along the circumferential direction of the half thrust bearing, and smooth surfaces and the circumferential grooves are alternately arranged on the recess surface.

Abstract: A main bearing for a journal portion of a crankshaft includes a pair of upper and lower half bearings forming a cylindrical shape. Each half bearing includes a main cylindrical portion including a circumferentially central portion and having a slide surface, and crush reliefs formed on both circumferential sides of the slide surface. Only the upper half bearing includes an oil groove on its inner peripheral surface, and an oil hole pierced from the oil groove to an outer peripheral surface. The lower half bearing includes an axial groove on the slide surface that is arranged apart from the circumferentially central portion toward the forward side by a circumferential angle of 10° or more, and apart from the crush relief located on the forward side by a circumferential angle of 10° or more.

Abstract: A connecting rod bearing for a crankpin of a crankshaft of an internal combustion engine includes a pair of half bearings forming a cylindrical shape. Each half bearing has a main cylindrical portion including a circumferentially central portion of the half bearing, and crush reliefs formed on both circumferential sides of the main cylindrical portion with a wall thickness being smaller than that of the main cylindrical portion. At least one half bearing has an axial groove which extends in an axial direction on a slide surface of the main cylindrical portion, and is apart from the circumferentially central portion by a circumferential angle of 10° or more toward a forward side in a rotation direction of the crankpin, and apart from the crush relief by a circumferential angle of 10° or more toward the circumferentially central portion.

Abstract: Provided is a semi-cylindrical-shaped half bearing having an inner surface including a center zone and end zones each including a plurality of recesses. Each recess includes a groove forming zone adjacent to the peripheral edge and including a plurality of circumferential grooves extending from the peripheral edge along the circumferential direction. An area ratio S2 of an area of the groove forming zone to an area of the recess in the end zone is larger than an area ratio S1 in the center zone. A maximum depth D4 of the circumferential groove in the end zone is larger than a maximum depth D2 of the circumferential groove in the center zone. A sliding bearing of the present invention includes the above half bearing.

Abstract: Provided is a semi-cylindrical shaped half bearing. The half bearing has an inner surface forming a sliding surface. The sliding surface includes a plurality of recesses. Each recess has a smooth recess surface recessed from the sliding surface toward an outer diameter side of the half bearing. The recess surface forms a convex curve toward the outer diameter side of the half bearing in a cross-sectional view in any direction perpendicular to the sliding surface. The recess surface includes a plurality of circumferential grooves. The circumferential grooves are recessed from the recess surface toward the outer diameter side of the half bearing. The circumferential grooves extend along a circumferential direction of the half bearing so that smooth surfaces and the circumferential grooves are alternately arranged on the recess surface.

Abstract: Provided is a semi-annular shaped half thrust bearing. The half thrust bearing has a sliding surface and a back surface opposite to the sliding surface. The sliding surface includes a plurality of recesses. Each recess has a recess surface recessed from the sliding surface toward the back surface. The recess surface is convex toward the back surface in cross-sectional view in a center line direction of the half thrust bearing. The recess surface includes a plurality of grooves. The grooves are recessed from the recess surface toward the back surface. The grooves extend in the center line direction so that smooth surfaces and the grooves are alternately arranged on the recess surface in a horizontal direction of the half thrust bearing.

Abstract: A main bearing for a journal portion of a crankshaft includes a pair of upper and lower half bearings combined with each other to form a cylindrical shape. Only the upper half bearing includes an oil groove formed on its inner peripheral surface to extend in a circumferential direction, an oil hole piercing from the oil groove to an outer peripheral surface of the upper half bearing, and a plurality of axial grooves formed on its inner peripheral surface to extend in an axial direction so as to intersect with the oil groove. A groove depth D2 of the axial groove is not more than 10% of a groove depth D1 of the oil groove, and an axial length L2 of the axial groove is not less than 70% of an axial length L1 of the upper half bearing.

Abstract: Provided is a semi-annular-shaped half thrust bearing having a sliding surface for receiving an axial force and a back surface opposite to the sliding surface. The sliding surface includes a plurality of recesses. Each recess has a recess surface recessed from the sliding surface toward the back surface of the half thrust bearing. The recess surface is convex toward the back surface of the half thrust bearing in cross-sectional view in a circumferential direction of the half thrust bearing. The recess surface includes a plurality of circumferential grooves recessed from the recess surface toward the back surface of the half thrust bearing. The circumferential grooves extend along the circumferential direction of the half thrust bearing, and smooth surfaces and the circumferential grooves are alternately arranged on the recess surface.

Abstract: Provided is a semi-cylindrical shaped half bearing. The half bearing has an inner surface forming a sliding surface and including a plurality of recesses. Each recess has a smooth recess surface and a peripheral edge. The recess surface forms a convex curve toward the outer diameter side of the half bearing in cross-sectional view in a direction parallel to a circumferential direction of the half bearing. The recess includes a groove forming zone adjacent to the peripheral edge of the recess. The groove forming zone includes a plurality of circumferential grooves. The circumferential grooves extend from the peripheral edge of the recess along the circumferential direction of the half bearing. The present invention also provides a cylindrical sliding bearing including the above half bearing.

Abstract: Provided is a semi-cylindrical-shaped half bearing having an inner surface including a center zone and end zones each including a plurality of recesses. Each recess includes a groove forming zone adjacent to the peripheral edge and including a plurality of circumferential grooves extending from the peripheral edge along the circumferential direction. An area ratio S2 of an area of the groove forming zone to an area of the recess in the end zone is larger than an area ratio S1 in the center zone. A maximum depth D4 of the circumferential groove in the end zone is larger than a maximum depth D2 of the circumferential groove in the center zone. A sliding bearing of the present invention includes the above half bearing.

Abstract: A main bearing for a journal portion of a crankshaft includes a pair of upper and lower half bearings forming a cylindrical shape. Each half bearing includes a main cylindrical portion including a circumferentially central portion and having a slide surface, and crush reliefs formed on both circumferential sides of the slide surface. Only the upper half bearing includes an oil groove on its inner peripheral surface, and an oil hole pierced from the oil groove to an outer peripheral surface. The lower half bearing includes an axial groove on the slide surface that is arranged apart from the circumferentially central portion toward the forward side by a circumferential angle of 10° or more, and apart from the crush relief located on the forward side by a circumferential angle of 10° or more.

Abstract: A connecting rod bearing for a crankpin of a crankshaft of an internal combustion engine includes a pair of half bearings forming a cylindrical shape. Each half bearing has a main cylindrical portion including a circumferentially central portion of the half bearing, and crush reliefs formed on both circumferential sides of the main cylindrical portion with a wall thickness being smaller than that of the main cylindrical portion. At least one half bearing has an axial groove which extends in an axial direction on a slide surface of the main cylindrical portion, and is apart from the circumferentially central portion by a circumferential angle of 10° or more toward a forward side in a rotation direction of the crankpin, and apart from the crush relief by a circumferential angle of 10° or more toward the circumferentially central portion.

Abstract: Provided is a semi-cylindrical shaped half bearing. The half bearing has an inner surface forming a sliding surface and including a plurality of recesses. Each recess has a smooth recess surface and a peripheral edge. The recess surface forms a convex curve toward the outer diameter side of the half bearing in cross-sectional view in a direction parallel to a circumferential direction of the half bearing. The recess includes a groove forming zone adjacent to the peripheral edge of the recess. The groove forming zone includes a plurality of circumferential grooves. The circumferential grooves extend from the peripheral edge of the recess along the circumferential direction of the half bearing. The present invention also provides a cylindrical sliding bearing including the above half bearing.

Abstract: A sliding resin composition is provided which hardly seizes by decreasing oil repellency of PTFE to prevent discharging of lubricating oil from sliding surface. That is, by using resin composition 1 where particles of PTFE 3 in the surface of which inorganic compound 4 having oil-absorptivity is embedded are dispersed in synthetic resin 2, the inorganic compound 4 having oil-absorptivity absorbs and retains lubricating oil, and oil repellency of PTFE 3 on the sliding surface can be decreased. Thus, discharging of the lubricating oil from the sliding surface can be inhibited and resin composition 1 hardly seizes.