Abstract: Provided is a bearing structure, including: a bearing housing having a bearing hole; a main body portion, which is provided in the bearing hole, and receives a shaft inserted to the main body portion; a damper portion formed on an outer circumference surface of the main body portion; a radial bearing surface formed on an inner circumference surface of the main body portion; a thrust bearing surface formed on one end surface of the main body portion in an axial direction of the shaft; a communication hole, which has one end opened in a gap between an outer circumference surface of the main body portion and an inner circumference surface of the bearing hole or in the damper portion, and has another end opened in the thrust bearing surface, in the radial bearing surface, or between the thrust bearing surface and the radial bearing surface.

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: A bearing structure includes: a housing; a bearing hole formed in the housing and provided with a bearing for pivotally supporting a shaft; a clearance groove provided in the bearing hole, having an opposing wall portion radially opposed to the shaft, and communicating with an oil drainage passage provided below a shaft center of the shaft; and at least one of a narrow portion or a wide portion in the opposing wall portion of the clearance groove with a boundary right above the shaft center of the shaft, the narrow portion provided in a rear side in a rotation direction of the shaft, the narrow portion having a narrower gap from the shaft than that in a front side in the rotation direction of the shaft, the wide portion provided in the front side in the rotation direction of the shaft, the wide portion having a wider gap from the shaft than that in the rear side in the rotation direction 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: a ball bearing disposed in a bearing hole formed in a housing of a turbocharger, the ball bearing having an outer ring formed with a damper portion on an outer circumferential surface thereof; an opposed member fixed to the housing, the opposed member opposed to the outer ring in an axial direction of a shaft; a protruding portion formed on one of the outer ring and the opposed member, the protruding portion protruding toward another one of the outer ring and the opposed member; and a regulating portion formed on the other one of the outer ring and the opposed member, the regulating portion opposed to the protruding portion in a rotation direction of the shaft.

Abstract: A bearing structure includes: a housing; a bearing hole formed in the housing; a bearing, which is provided in the bearing hole, and is configured to axially support a shaft having one end provided with a turbine impeller; a space, which is formed in the housing, and is positioned between the impeller and the bearing hole; a passage, which communicates with the space, and extends to a vertically lower side of the bearing hole; a communication opening portion, which allows the passage and the bearing hole to communicate with each other; and a lower wall portion, which is provided in a lower portion including a portion directly below an axis of the shaft between the passage and the bearing hole, and has an inner wall surface being opposed to the shaft and having a curved surface shape with a curvature center positioned on the shaft side.

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 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: 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 bearing housing (housing); a bearing disposed in the housing and having a thrust bearing surface; and a partition wall portion assembled to the housing, the partition wall portion including an inclined surface positioned on an outer side in a radial direction of the thrust bearing surface, extending at least vertically above the thrust bearing surface, and inclined with respect to a direction perpendicular to the axial direction of a shaft.

Abstract: Provided is a mounting structure, including: an impeller including: a main body portion having a through hole; a plurality of blades provided to an outer peripheral surface of the main body portion; and a boss portion, which is a part of the main body portion, and protrudes toward one end side of the shaft with respect to the plurality of blades; a small-diameter portion, which is a part of the shaft; a first large-diameter portion, which is a part of the shaft, is located on another end side of the shaft with respect to the small-diameter portion; and a small-inner-diameter portion of the through hole, which is formed on a radially inner side of the boss portion, and has an inner diameter smaller than an inner diameter of a part of the through hole which is opposed to the first large-diameter portion in a radial direction.

Abstract: Provided is a bearing structure, including: a bearing housing having a bearing hole; a main body portion, which is provided in the bearing hole, and receives a shaft inserted to the main body portion; a damper portion formed on an outer circumference surface of the main body portion; a radial bearing surface formed on an inner circumference surface of the main body portion; a thrust bearing surface formed on one end surface of the main body portion in an axial direction of the shaft; a communication hole, which has one end opened in a gap between an outer circumference surface of the main body portion and an inner circumference surface of the bearing hole or in the damper portion, and has another end opened in the thrust bearing surface, in the radial bearing surface, or between the thrust bearing surface and the radial bearing surface.

Abstract: A bearing structure S includes: a bearing hole formed in a housing; a main body portion of a bearing provided in the bearing hole and inserted with a shaft therethrough; damper surface and provided on an outer circumferential surface of the main body portion, the damper surface facing an inner circumferential surface of the bearing hole; thrust surface provided at end portions of the main body portion in an axial direction of the shaft; and thrust back surface portions provided in the main body portion and having an outer diameter larger than those of the damper surface, the thrust back surface portions spaced apart from the damper surface by a distance farther than a distance between each of the damper surface and the inner circumferential surface of the bearing hole and positioned on back sides of the thrust surface.

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 bearing structure includes: a housing; a bearing hole formed in the housing; a bearing, which is provided in the bearing hole, and is configured to axially support a shaft having one end provided with a turbine impeller; a space, which is formed in the housing, and is positioned between the impeller and the bearing hole; a passage, which communicates with the space, and extends to a vertically lower side of the bearing hole; a communication opening portion, which allows the passage and the bearing hole to communicate with each other; and a lower wall portion, which is provided in a lower portion including a portion directly below an axis of the shaft between the passage and the bearing hole, and has an inner wall surface being opposed to the shaft and having a curved surface shape with a curvature center positioned on the shaft side.

Abstract: A bearing structure includes: a housing; a bearing hole formed in the housing and provided with a bearing for pivotally supporting a shaft; a clearance groove provided in the bearing hole, having an opposing wall portion radially opposed to the shaft, and communicating with an oil drainage passage provided below a shaft center of the shaft; and at least one of a narrow portion or a wide portion in the opposing wall portion of the clearance groove with a boundary right above the shaft center of the shaft, the narrow portion provided in a rear side in a rotation direction of the shaft, the narrow portion having a narrower gap from the shaft than that in a front side in the rotation direction of the shaft, the wide portion provided in the front side in the rotation direction of the shaft, the wide portion having a wider gap from the shaft than that in the rear side in the rotation direction of the shaft.

Abstract: A bearing structure includes: a housing; a bearing hole, which is formed in the housing, and receives a bearing configured to axially support a shaft having one end provided with an impeller; a clearance groove, which is formed in an inner circumferential surface of the bearing hole, and communicates with a passage formed on a lower side of the shaft; and an inclined portion formed on an inner wall surface of the clearance groove, which is positioned at least above the shaft.

Abstract: A bearing structure includes: a ball bearing disposed in a bearing hole formed in a housing of a turbocharger, the ball bearing having an outer ring formed with a damper portion on an outer circumferential surface thereof; an opposed member fixed to the housing, the opposed member opposed to the outer ring in an axial direction of a shaft; a protruding portion formed on one of the outer ring and the opposed member, the protruding portion protruding toward another one of the outer ring and the opposed member; and a regulating portion formed on the other one of the outer ring and the opposed member, the regulating portion opposed to the protruding portion in a rotation direction of the shaft.

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.