Abstract:
The provided is a bearing device for a crankshaft of an internal combustion engine including: a crankshaft having a plurality of journal portions; main bearings for supporting the crankshaft; and a bearing housing, wherein a range in which the oil groove of the upper-side halved bearing of the second main bearing is formed in the circumferential direction includes at least a range of a circumferential angle of 20° within the ±45° region, a circumferential end portion of the oil groove on a rotationally forward side communicates with the crush relief at a minimum, and is open to a circumferential end face at a maximum, and a circumferential end portion of the oil groove on the rotationally backward side of the journal portion is positioned on a circumferential center portion side of the upper-side halved bearing from a circumferential end face of the upper-side halved bearing.
Abstract:
A split-type sliding bearing for a crankshaft in an internal combustion engine incorporated in a split-type bearing housing. The sliding bearing consists of a pair of semi-cylindrical bearing bodies combined with each other to form a cylindrical body. The bearing housing has a cylindrical bearing retaining bore and consists of a pair of housing halves. One of the housing halves has a relatively lower stiffness, and the other has a relatively higher stiffness. One of the bearing bodies is held by the housing half having a relatively lower stiffness. The other bearing body is held by the housing half having a relatively higher stiffness. The bearing bodies have an equal outer diameter to each other, and both of the circumferential end parts of one bearing body have a larger thickness than those of the other bearing body prior to incorporation into the housing halves.
Abstract:
The bearing apparatus 1 includes a crankshaft having multiple journals, main bearings supporting the crankshaft, and a bearing housing. The plurality of journals include a first journal with a lubricating oil passage and a second journal without a lubricating oil passage. The first and second journals are supported by first and second main bearings, respectively. The bearing housing is constituted by an Al-alloy upper housing and an Fe-alloy lower housing. The depth of the oil groove of the upper half bearing of the second main bearing at least in a ±45° region is equal to or smaller than a half of the depth of the oil groove of the upper half bearing of the first main bearing in the ±45° region.
Abstract:
Provided is a sliding member including a steel back metal layer and a sliding layer with a porous sintered layer and a resin composition. The porous sintered layer includes granular Fe or Fe alloy phase and Ni—P alloy phase for binding the Fe or Fe alloy phase grains with one another. The steel back metal layer is made of a carbon steel including 0.05-0.3 mass % of carbon and having a structure composed of ferrite phase and pearlite phase, and includes a low pearlite phase part in a surface thereof on a side of the sliding layer. The low pearlite phase part has a ratio of the pearlite phase is lowered by 50% or more compared with the pearlite phase at a central part in a thickness direction of the steel back metal layer. The Ni—P alloy phase may cover the entire surface of the steel back metal layer.
Abstract:
Provided is a half bearing constituting a sliding bearing for a shaft member of an internal combustion engine that is unlikely to cause seizure in a sliding surface even if deflection or whirling of the shaft member occurs during an operation of the internal combustion engine. In a half bearing that constitutes a sliding bearing, a plurality of circumferential-direction grooves are formed to be adjacent to each other in a sliding surface including first and second curved surfaces with different curvatures, the sliding surface includes a plane portion that is parallel to an axial line direction and an inclined surface portion that is adjacent to the plane portion, the inclined surface portion is displaced from the plane portion toward an end portion of the sliding surface in the axial line direction such that the sliding surface successively comes close to a back surface, positions of maximum groove depths of the circumferential-direction grooves are located on groove center lines, the groove center lines in the inclined surface portion of the sliding surface are inclined relative to a vertical line toward the end portion of the sliding surface in the axial line direction, a groove inclination angle of the circumferential-direction grooves that are closest to the plane portion is a minimum angle, and the groove inclination angle successively increases toward the end portion of the sliding surface in the axial line direction.
Abstract:
A bearing device includes a crankshaft having a plurality of journal portions, main bearings for supporting the crankshaft, and a bearing housing. The plurality of journal portions includes a first journal portion with a lubricating oil passage and a second journal portion without the lubricating oil passage. The first and second journal portions are supported by the first and second main bearings. The bearing housing includes an upper-side housing and a lower-side housing. A length of a crush relief of at least an upper-side halved bearing of the second main bearing is larger than a length of the crush relief of each of upper-side and lower-side halved bearings of the first main bearing.
Abstract:
Provided is a half bearing constituting a sliding bearing for a shaft member of an internal combustion engine that is unlikely to cause seizure in a sliding surface even if deflection or whirling of the shaft member occurs during an operation of the internal combustion engine. In a half bearing that constitutes a sliding bearing, a plurality of circumferential-direction grooves are formed to be adjacent to each other in a sliding surface, the sliding surface includes a plane portion that is parallel to an axial line direction and an inclined surface portion that is adjacent to the plane portion, the inclined surface portion is displaced from the plane portion toward an end portion of the sliding surface in the axial line direction such that the sliding surface successively comes close to a back surface, positions of maximum groove depths of the circumferential-direction grooves are located on groove center lines, the groove center lines in the inclined surface portion of the sliding surface are inclined relative to a vertical line toward the end portion of the sliding surface in the axial line direction, a groove inclination angle of the circumferential-direction groove that is the closest to the plane portion is a minimum angle, and the groove inclination angle successively increases toward the end portion of the sliding surface in the axial line direction.
Abstract:
Provided is a sliding member having: a back metal layer; and a sliding layer on the back metal layer. The sliding layer includes a porous sintered layer and a resin composition. The sintered layer includes Ni—P alloy phase and granular steel phase made of a carbon steel including 0.3-1.3 mass % of carbon and having a structure of: ferrite phase; and perlite phase, or perlite phase and cementite phase. The Ni—P alloy phase binds the steel phases with one another and/or binds the steel phases with the back metal layer. The steel phase includes a low perlite phase part in a surface. The low perlite phase part has an area ratio of the perlite phase lowered by 50% or more compared with a total area ratio of the perlite phase and the cementite phase at a central part of the steel phase when observed in a cross-section.