A compressor includes: an impeller including a hub and a plurality of blades disposed on an outer surface of the hub; and a housing which houses the impeller. The housing includes: a shroud section facing the outer surface of the hub to form a fluid flow path between the shroud section and the outer surface, and surrounding the impeller; and a casing section formed integrally with the shroud section and supporting the shroud section. The shroud section includes a first resin-based material having a static tensile strength of at least 65 MPa and no more than 200 MPa and a breaking strain of no more than 0.3 mm/mm at a temperature of 100 C. The casing section includes a second resin-based material having a static tensile strength of at least 40 MPa and a breaking strain of at least 0.1 mm/mm at a temperature of 100 C.

An oil film damper of a bearing structure is located between facing surfaces of two bearings. The oil film damper includes two protrusions protruding inward in a radial direction from an inner circumferential surface of a main body portion, an oil guiding passage penetrating through from the protrusion to an outer circumferential surface of the main body portion and guiding a lubricating oil from the outer circumference of the main body portion to the bearing, an inclined surface provided on a side opposite to the adjacent surface adjacent to the bearing in the protrusion and having an inner diameter gradually increasing as the diameter is separate from the adjacent surface in the rotation axis direction of the shaft, and an oil discharge hole provided between the two protrusions of the main body portion and discharging the lubricating oil to an outside from an inside of the main body portion.

An oil film damper of a bearing structure is located between facing surfaces of two bearings. The oil film damper includes two protrusions protruding inward in a radial direction from an inner circumferential surface of a main body portion, an oil guiding passage penetrating through from the protrusion to an outer circumferential surface of the main body portion and guiding a lubricating oil from the outer circumference of the main body portion to the bearing, an inclined surface provided on a side opposite to the adjacent surface adjacent to the bearing in the protrusion and having an inner diameter gradually increasing as the diameter is separate from the adjacent surface in the rotation axis direction of the shaft, and an oil discharge hole provided between the two protrusions of the main body portion and discharging the lubricating oil to an outside from an inside of the main body portion.

A method for identifying a surge limit of a compressor. The compressor is driven at least by an electric motor, the power of which is regulated by means of a regulation device. The regulation device detects regulation activity during the operation of the compressor. A surge limit of the compressor is identified if the regulation activity or a change in the regulation activity overshoots a threshold value which is assigned to the surge limit.

A method for identifying a surge limit of a compressor. The compressor is driven at least by an electric motor, the power of which is regulated by means of a regulation device. The regulation device detects regulation activity during the operation of the compressor. A surge limit of the compressor is identified if the regulation activity or a change in the regulation activity overshoots a threshold value which is assigned to the surge limit.

Methods and systems are provided for a compressor of a turbocharger of an engine. In one example, a compressor may include a flow passage and a resonance chamber surrounding the flow passage, with the flow passage fluidly coupled with the resonance chamber by a recirculation passage, a bleed passage, and a plurality of apertures positioned between the recirculation passage and the bleed passage. Flowing fluid from the resonance chamber, through the apertures, and into the flow passage may reduce a noise level of the compressor.

A turbocharger (1) includes compressor and turbine wheels (4, 5) and a shaft (6) that connects the compressor wheel (5) to the turbine wheel (4). The shaft (6) is supported by a thrust bearing assembly (20) that includes a pair of thrust washers (42a, 42b) mounted on the shaft (6), a hollow, cylindrical spacer (80) disposed on the shaft (6) between and abutting first faces (44) of the thrust washers (42a, 42b), and a thrust bearing (100) supported on the spacer (80) between the thrust washers (42a, 42b). One of the thrust bearing (100) or the first and second thrust washers (42a, 42b) includes a copper-alloy lining (60) where the lining (60) is provided in a first region (58a) and in a second region (58b), and the remainder of the thrust bearing (100) or the first and second thrust washers (42a, 42b) is lining free.

A turbocharger (1) includes compressor and turbine wheels (4, 5) and a shaft (6) that connects the compressor wheel (5) to the turbine wheel (4). The shaft (6) is supported by a thrust bearing assembly (20) that includes a pair of thrust washers (42a, 42b) mounted on the shaft (6), a hollow, cylindrical spacer (80) disposed on the shaft (6) between and abutting first faces (44) of the thrust washers (42a, 42b), and a thrust bearing (100) supported on the spacer (80) between the thrust washers (42a, 42b). One of the thrust bearing (100) or the first and second thrust washers (42a, 42b) includes a copper-alloy lining (60) where the lining (60) is provided in a first region (58a) and in a second region (58b), and the remainder of the thrust bearing (100) or the first and second thrust washers (42a, 42b) is lining free.

Disclosed is a controller for a turbocharged engine. The engine includes a supercharger configured to supercharge intake air using an exhaust gas from the engine, and including movable flaps arranged so that a boost pressure generated in an intake passage is adjustable. If a rotational speed of a turbine and compressor that constitute the supercharger has reached a first threshold lower than an endurance limit, an amount of fuel injected to the engine is reduced to a predetermined amount. If the rotational speed has reached a second threshold lower than the first threshold, the amount of fuel injected is reduced in accordance with an excess of the rotational speed over the second threshold.

Disclosed is a controller for a turbocharged engine. The engine includes a supercharger configured to supercharge intake air using an exhaust gas from the engine, and including movable flaps arranged so that a boost pressure generated in an intake passage is adjustable. If a rotational speed of a turbine and compressor that constitute the supercharger has reached a first threshold lower than an endurance limit, an amount of fuel injected to the engine is reduced to a predetermined amount. If the rotational speed has reached a second threshold lower than the first threshold, the amount of fuel injected is reduced in accordance with an excess of the rotational speed over the second threshold.