Taiho Kogyo Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Nippon Steel Corporation

Yuichiro Kajiki

Hiroki Takata

Katsuhiro Ashihara

Motoichi Murakami

Akihiro Honda

Yusuke Morita

Takeshi Fukui

Keiji Yuda

Shuu Kamiya

Yasushi Nakatake

Takashi Koyama

Manabu Kubota

Tatsuhiko Abe

Satoru Okawa

Yusuke Inukai

Alan Hase

Takashi Izumi

A crankshaft with improved seizure resistance is provided. A crankshaft () is a crankshaft including journals () and pins (), having a chemical composition of, in mass %: 0.35 to 0.40% C; up to 0.70% Si; 1.00 to 2.00% Mn; up to 0.50% Cr; up to 0.050% Al; up to 0.020% N; up to 0.020% P; 0.005 to 0.200% S; and balance Fe and impurities, each of the journals () and pins () having a surface microstructure containing tempered martensite in not less than 80 volume % and a surface hardness not higher than HV 450.

Crankshaft

A half bearing includes circumferentially extending first and second grooves on the inner circumferential surface. The circumferential end of the first groove, on the rotational upstream side of the shaft, has an inclination angle &#x3b8;1 of 135&#xb0; formed by: a first imaginary line connecting the inner circumferential surface end of a mating surface and the origin of an outer circumferential surface; and a second imaginary line connecting the end of the first groove and the origin of the outer circumferential surface. The circumferential end of the second groove, on the rotational upstream side of the shaft, has an inclination angle &#x3b8;2 of 135&#xb0; formed by: a first imaginary line connecting the inner circumferential surface end of the mating surface and the origin of the inner circumferential surface; and a third imaginary line connecting the end of the second groove and the origin of the outer circumferential surface.

Half bearing

A half bearing is provided with a first groove and a second groove on the inner circumferential surface side. The first and second grooves extend in the circumferential direction of the inner circumferential surface, and retain lubricating oil. The end of the first groove in the circumferential direction, on the downstream side in the rotational direction of the shaft (the end on the crush relief side), is located away from a crush relief so as not to reach the crush relief. Also, the end of the second groove in the circumferential direction, on the downstream side in the rotational direction of the shaft (the end on the crush reliefside), is located away from the crush relief so as not to reach the crush relief.

A control device controls an internal combustion engine including: an elastic wave sensor arranged and configured to output a signal responsive to the strength of an acoustic emission wave produced at a sliding portion; and a variable oil pump. The control device is configured to execute an oil pressure control such that the oil pressure approaches a target oil pressure according to an engine operating condition. This oil pressure control includes a first pressure-increase processing executed where an AE correlation value correlated with the strength or occurrence frequency of the acoustic emission wave detected by the elastic wave sensor is greater than a first threshold value. The first pressure-increase processing increases the target oil pressure associated with a first engine operating condition present when the AE correlation value becomes greater than the first threshold value, as compared to when the AE correlation value is not greater than that.

Control device for internal combustion engine

A half bearing includes: a semi-cylindrical bearing body having an inner circumferential surface that slides against a counterpart shaft; and a first groove formed in the inner circumferential surface so as to extend in a circumferential direction of the inner circumferential surface. In a cross section that is parallel with the circumferential direction and passes through the first groove, of the bearing body, an angle &#x3b8; satisfies 90&#xb0;&#x2264;&#x3b8;&#x2264;105&#xb0;, where the angle &#x3b8; is formed by: a line connecting the inner circumferential surface side end of a mating surface located on a downstream side in a rotational direction of the counterpart shaft with the center point of a circular arc constituting an outer circumferential surface; and a line connecting an end of the first groove in the circumferential direction, on the upstream side in the rotational direction of the counterpart shaft, with the center point.

There is provided a slide bearing capable of preventing or reducing a temperature increase in lubricant. A cylindrical main bearing is formed by combining a pair of upper bearing and lower bearing and rotatably supports a crank journal. The lower bearing includes a downstream crush relief formed at a downstream end in the rotation direction of the crank journal in an inner periphery of the lower bearing; and an oil groove formed in the inner periphery of the lower bearing so as to communicate with the downstream crush relief.

Slide bearing

Slide bearing and lubricant feed mechanism having the same

Provided is a slide bearingwith which friction can be reduced and the total amount of effluent oil can be reduced. In the slide bearing in which halved members, made by dividing a cylinder in two in a direction parallel to the axial direction are disposed vertically, grooves are provided at an end of the axial direction of the lower halved member in the circumferential direction and the depth of the groove in the radial direction is changed corresponding to the circumstance direction and the gradient of the depth (d) of the groove in the radial direction is configured in asymmetry using the center (the bearing angle (&#x3c9;) is (&#x3c9;2)) in the circumferential direction as a symmetry axis.

Sliding bearing

Provided is a slide bearing with which friction can be reduced and the total amount of effluent oil can be reduced. In the slide bearing in which halved members, made by dividing a cylinder in two in a direction parallel to the axial direction are disposed vertically, grooves are provided at an end of the axial direction of the lower halved member in the circumferential direction and the height of a peripheral edge part configured at the outside of the groove in the axial direction is changed corresponding to the circumstance direction and the gradient of the height of the peripheral edge part is configured in asymmetry using the center (the bearing angle (&#x3c9;) is (&#x3c9;)) in the circumferential direction as a symmetry axis.

A slide bearing, in which halved members, made by dividing a cylinder parallel to the axial direction are disposed vertically, includes a groove circumferentially provided at the axial end of a lower halved member and a recess provided on an axially outer periphery of the groove, where a circumferential length of the recess is formed to be shorter than a length of the groove. The recess is formed such that its upstream end in the axial rotation direction aligns with an upstream end in the rotation direction of the groove. The recess is formed such that its downstream end in the rotation direction is located upstream relative to the circumferential center of the groove.

Provided is a sliding bearing that has a bearing inner peripheral surface covered by a resin overlay layer configured from a binder resin and a solid lubricant and/or hard substance, reduces the running-in time during an operation start, and can obtain the effect of increasing wear resistance and the effect of reducing friction. In the sliding bearing, halved members resulting from halving a cylinder parallel to the axial direction are disposed at the top and bottom, the inner peripheral surfaces of the top and bottom halved members are covered by a resin overlay layer configured from a binder resin and a solid lubricant and/or hard substance, and a fine groove is provided to an axial-direction end of the bottom halved member in the peripheral direction from the mating surface at the downstream side in the rotational direction to a predetermined bearing angle.

Provided is a slide bearing with which friction can be reduced and the total amount of effluent oil can be reduced. In the slide bearing in which the halved members made by dividing the cylinder in two in the direction parallel to the axial direction are disposed vertically, the narrow grooves are provided at an end of the lower halved member in the circumferential direction from a mating surface on a downstream side of a rotation direction to a predetermined bearing angle and peripheral edge parts are provided outside the narrow grooves in an axial direction.

Provided is a slide bearing with which friction-reducing effects are obtained and the total volume of effluent oil is limited. In a slide bearing an end of the narrow groove on a downstream side of the rotation direction is disposed at the position which is adjacent to a mating surface on the downstream side of the rotation direction and not communicated with the mating surface on the downstream side of the rotation direction and an end of the narrow groove on an upstream side of the rotation direction is disposed at the position which is the upstream side from the end on the downstream side of the rotation direction and is rotated by an angle no more than 90 degrees from the mating surface on the downstream side of the rotation direction.

Provided is a slide bearing with which friction-reducing effects can be obtained and the total volume of effluent oil can be limited. A slide bearing in which halved members made by dividing a cylinder in two in a direction parallel to the axial are disposed vertically, wherein narrow grooves are provided at the ends of the slide bearing in the axial direction, the narrow grooves extending in the circumferential direction from the mating surface on the downstream side of the rotation direction to a specified bearing angle is an angle rotated in the range of &#x2267;0 degree to &#x2266;90 degrees from the mating surface on the downstream side in the rotation direction (bearing angle of 180 degrees) towards the upstream side in the rotation direction. In other words, the bearing angle is the range of 180 degrees to 270 degrees.

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Toyota, Japan

Yuichiro Kajiki