Abstract: An wheel fastening inspection method includes: directly or indirectly applying vibration to a turbine shaft to be inserted to a bearing housing, the turbine shaft being provided with wheels at both ends protruding from the bearing housing, at least one of the wheels being fastened by a fastening member, and a rotary member being fastened by a fastening force generated by the fastening member to the turbine shaft to be integrally rotated with the wheel; measuring the vibration of the turbine shaft; and determining whether or not a vibration frequency at which a peak of the measured vibration of the turbine shaft is given is included in a setting range previously set.

Abstract: A turbocharger includes: a bearing provided in a turbocharger body, and configured to rotatably support a turbine shaft in an insertion hole formed in the bearing; and an opposing portion which faces an end surface of the bearing in an axial direction of the turbine shaft. An end-surface guide portion is provided to any one of an opposing surface of the bearing which faces the apposing portion, and an opposing surface of the opposing portion which faces the bearing. The end-surface guide portion configured to make the insertion hole and an outer peripheral edge of the end surface of the bearing in radial directions of the turbine shaft communicate with each other extends forward in a rotational direction of the turbine shaft from a part of the end surface of the bearing which communicates with the insertion hole.

Abstract: A turbocharger includes: a bearing provided in a turbocharger body, and configured to rotatably support a turbine shaft in an insertion hole formed in the bearing; and an opposing portion which faces an end surface of the bearing in an axial direction of the turbine shaft. An end-surface guide portion is provided to any one of an opposing surface of the bearing which faces the opposing portion, and an opposing surface of the opposing portion which faces the bearing. The end-surface guide portion configured to make the insertion hole and an outer peripheral edge of the end surface of the bearing in radial directions of the turbine shaft communicate with each other extends forward in a rotational direction of the turbine shaft from a part of the end surface of the bearing which communicates with the insertion hole.

Abstract: A bearing structure includes: a bearing hole formed in a bearing housing, a semi-floating metal bearing accommodated in the bearing hole and having a pin hole formed therein; a through-hole formed in the bearing housing and facing the pin hole in the semi-floating metal bearing; a regulating member which is inserted into the through-hole and in which a fixed portion is pressed onto an inner surface of the through-hole for the regulating member to be fixed to the bearing housing at a fixed position where a distal end portion is inserted into the pin hole; a regulating hole opened at a base end in the insertion direction of the regulating member and extending at least to the fixed portion toward the distal end side; and a pressing member provided in the regulating hole to expand the regulating hole by pressing an inner surface of the regulating hole.

Abstract: A valve is provided fitted into a mounting hole of a mounting member. The valve is allowed to have play with respect to the mounting member. The valve includes a valve body having a valve surface capable of being brought into contact with and being separated from a valve seat. A valve shaft is integrally formed on a head of the valve body. An axial center of the bypass passage is inclined with respect to a thickness direction of an inner wall portion of a turbine housing so that an opening portion on an outlet side in the bypass passage is located closer to a stem side than an opening portion on an inlet side. A center of the valve surface of the valve body is eccentric to the stem side with respect to an axial center of the valve shaft.

Abstract: An actuating rod of an actuator is rotatably connected to a distal end portion of a link member, a connecting pin is integrally provided at a distal end portion of the actuator rod, a pin hole for allowing insertion of the connecting pin is penetrated and formed at a distal end portion of the link member, and a disc spring for biasing the distal end portion of the link member and the distal end portion of the actuating rod in an axial direction (both sides of the axial direction) of the actuating rod as directions opposite to each other between the distal end portion of the link member and the distal end portion of the actuator rod.

Abstract: In a variable-flow-rate valve mechanism, a valve is fitted into an attachment hole of an attachment member. The valve allows for play with the attachment member, and includes a valve body provided with a valve surface. A valve shaft is integrally formed in the center of a head portion of the valve body. A stopping member is provided to a leading end portion of the valve shaft. A leaf spring is provided to the valve shaft. The leaf spring includes a folded-back portion formed by bending. An insertion hole is formed in one end portion of the leaf spring. A cutout portion is formed in another end portion of the leaf spring. The one end portion of the leaf spring is fixed to the attachment member and the other end portion of the leaf spring is pressed to the head portion of the valve body.

Abstract: A turbocharger includes: a thrust bearing fixed to a turbocharger main body; and a supply oil passage provided in the turbocharger main body to the thrust bearing. The thrust bearing includes: an insertion hole in which to insert the turbine shaft; pressure receiving portions displaced from one another in phase in a rotational direction of the turbine shaft, and each configured to form an oil film between the pressure receiving portion and the thrust collar to receive a thrust load by use of oil film pressure; and intervening portions each located between two of the pressure receiving portions adjacent in the rotational direction of the turbine shaft, and being further away from the thrust collar than the pressure receiving portions. The intervening portion vertically under the insertion hole at least partially has a surface further away from the thrust collar than the other intervening portions.

Abstract: A bearing structure includes a bearing holder that has a hollow main body and an oil hole penetrating through from an outer circumferential surface to an inner circumferential surface of the main body to thereby guide a lubricating oil to the inside of the main body, and that is fixed in a bearing housing; two full-floating metal bearings that are arranged separated from each other in the axial direction of the shaft and support the shaft, in the bearing holder; two thrust bearing surfaces each arranged on the outside of two full-floating metal bearings in the axial direction of the shaft; and two collars each arranged on the outside of two thrust bearing surfaces in the axial direction of the shaft and provided for the shaft. The lubricating oil lubricates thrust bearing surfaces after lubricating full-floating metal bearings.

Abstract: A bearing structure includes a shaft including an wheel provided at least at one end and a semi-floating metal bearing rotatably supporting the shaft. The semi-floating metal bearing has a main body including a cylindrical shape, a bearing surface formed on an inner circumferential surface of the main body and supporting the shaft, and a plurality of bearing grooves provided at intervals in a circumferential direction in the bearing surface and extending from one end to the other end of the shaft in a rotation axis direction. At least one of a shape and arrangement of the plurality of bearing grooves is asymmetrical to a center of a rotation axis in a section perpendicular to the rotation axis of the shaft.

Abstract: A bearing structure includes a through-hole penetrating through in the axial direction of shaft, a bearing holder accommodated in the through-hole, a semi-floating metal bearing accommodated in the bearing holder and supporting the shaft inserted into the inside, and a positioning member being inserted into a radial direction of the shaft for both the bearing holder and the semi-floating metal bearing and regulating movement of the semi-floating metal bearing in the axial direction and in a rotating direction of the shaft relative to the bearing holder. For the bearing holder, a press-fit portion to be press-fitted into the through-hole is formed. A gap is formed between at least one of outer circumferential surfaces of both end parts of the bearing holder in the axial direction and the inner circumferential surface of the through-hole.

Abstract: A bearing structure includes: an outer circumferential groove formed on an outer circumferential surface of a cylindrical portion of a semi-floating metal bearing, and including two opposed surfaces opposed to each other in an axial direction of a shaft and a bottom surface connected to the two opposed surfaces; a radial hole penetrating a wall portion defining the bearing hole so as to communicate with the bearing hole, and facing the outer circumferential groove of the semi-floating metal bearing; a locking member having a body inserted into the radial hole from the outer side of the shaft, wherein at least part of the body is interposed between the two opposed surfaces and fixed to the outer circumferential groove; and an opposed portion provided in the housing, and opposed to the part of the body of the locking member when the locking member is fixed to the outer circumferential groove.

Abstract: A turbocharger includes: a shaft provided with a small-diameter portion, and two large-diameter portions formed on two sides of the small-diameter portion; and a semi-floating bearing to rotatably support the shaft. The semi-floating bearing includes a cylindrical body into which the shaft is inserted. An inner peripheral surface of the body includes: two bearing surfaces opposed to the large-diameter portions of the shaft; a non-bearing surface located between the two bearing surfaces, having a larger inner diameter than inner diameters of the bearing surfaces; and an oil passage opened to the non-bearing surface to supply lubricant oil to a gap in a radial direction between the non-bearing surface and the shaft. At least one of the two bearing surfaces extends more in an approaching direction of the two bearing surfaces than does the large-diameter portion opposed in the radial direction to the one bearing surface.

Abstract: A thrust bearing structure is equipped with a thrust collar having a collar pad, and a thrust bearing having a bearing pad at a position corresponding to the collar pad on a surface facing the thrust collar. The bearing pad has a tapered section, and a land section continuously formed on the outer edge of the tapered section. Assuming that oil droplets are supplied between the bearing pad and the collar pad, and assuming that the rotation speed of a rotor shaft is constant, the tapered section would have a sloping surface formed in such a manner that a wall thickness gradually becomes thicker toward the downstream side along the trajectory of given oil droplets based on the centrifugal forces acting on the droplets due to the rotation of the rotor shaft.

Abstract: An wheel fastening inspection method includes: directly or indirectly applying vibration to a turbine shaft to be inserted to a bearing housing, the turbine shaft being provided with wheels at both ends protruding from the bearing housing, at least one of the wheels being fastened by a fastening member, and a rotary member being fastened by a fastening force generated by the fastening member to the turbine shaft to be integrally rotated with the wheel; measuring the vibration of the turbine shaft; and determining whether or not a vibration frequency at which a peak of the measured vibration of the turbine shaft is given is included in a setting range previously set.

Abstract: A turbocharger includes: a bearing provided in a turbocharger body, and configured to rotatably support a turbine shaft in an insertion hole formed in the bearing; and an opposing portion which faces an end surface of the bearing in an axial direction of the turbine shaft. An end-surface guide portion is provided to any one of an opposing surface of the bearing which faces the opposing portion, and an opposing surface of the opposing portion which faces the bearing. The end-surface guide portion configured to make the insertion hole and an outer peripheral edge of the end surface of the bearing in radial directions of the turbine shaft communicate with each other extends forward in a rotational direction of the turbine shaft from a part of the end surface of the bearing which communicates with the insertion hole.

Abstract: A turbocharger includes: a turbocharger main body; a bearing hole formed in the turbocharger main body; a turbine shaft rotatably inserted into the bearing hole and having a turbine wheel provided on one end and a compressor wheel provided on the other end; a turbine-side bearing part and a compressor-side bearing part rotatably supporting the turbine shaft and disposed in the bearing hole on a relatively turbine wheel side and on a relatively compressor wheel side, respectively; a cooling oil passage provided radially outside the bearing hole in the turbocharger main body and configured to cool the turbocharger main body with lubricating oil circulated inside; a first oil duct configured to guide lubricating oil after lubricating the compressor-side bearing part to the cooling oil passage; and a second oil duct configured to guide lubricating oil after lubricating the turbine-side bearing part to the cooling oil passage.

Abstract: A turbocharger includes: a thrust bearing fixed to a turbocharger main body; and a supply oil passage provided in the turbocharger main body to the thrust bearing. The thrust bearing includes: an insertion hole in which to insert the turbine shaft; pressure receiving portions displaced from one another in phase in a rotational direction of the turbine shaft, and each configured to form an oil film between the pressure receiving portion and the thrust collar to receive a thrust load by use of oil film pressure; and intervening portions each located between two of the pressure receiving portions adjacent in the rotational direction of the turbine shaft, and being further away from the thrust collar than the pressure receiving portions. The intervening portion vertically under the insertion hole at least partially has a surface further away from the thrust collar than the other intervening portions.

Abstract: A thrust bearing structure is equipped with a thrust collar having a collar pad, and a thrust bearing having a bearing pad at a position corresponding to the collar pad on a surface facing the thrust collar. The bearing pad has a tapered section, and a land section continuously formed on the outer edge of the tapered section. Assuming that oil droplets are supplied between the bearing pad and the collar pad, and assuming that the rotation speed of a rotor shaft is constant, the tapered section would have a sloping surface formed in such a manner that a wall thickness gradually becomes thicker toward the downstream side along the trajectory of given oil droplets based on the centrifugal forces acting on the droplets due to the rotation of the rotor shaft.