Compressor housing for turbocharger and method for manufacturing the same

Abstract

A compressor housing for a turbocharger including a refrigerant flow path and a recirculation part, which is dividably composed of a scroll piece and a shroud piece. The refrigerant flow path is formed as an annular space that is defined by a first flow-path formation part of the scroll piece and a second flow-path formation part of the shroud piece that are fitted with each other. In the refrigerant flow path, a first press-fitting portion of the shroud piece is press-fitted into a first press-fitted portion of the scroll piece to form an inner circumferential seal part, and a second press-fitting portion of the shroud piece is press-fitted into a second press-fitted portion of the scroll piece to form an outer circumferential seal part. The recirculation part recirculates part of the air which has reached the shroud part to an upstream of the compressor impeller.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]The present application claims priority under 35 U.S.C. § 119 to Japanese Application No. 2019-026413, filed on Feb. 18, 2019, entitled “COMPRESSOR HOUSING FOR TURBOCHARGER AND METHOD FOR MANUFACTURING THE SAME”. The contents of this application are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTIONField of the Invention[0002]The present disclosure relates to a compressor housing for a turbocharger and a method for manufacturing the same.Description of the Related Art[0003]A turbocharger to be mounted on an internal combustion engine of an automobile, etc. includes a compressor impeller and a turbine impeller, which are housed in a housing. The compressor impeller is disposed in an air flow path that is formed inside the housing. The air flow path is provided with an intake port for sucking in air toward the compressor impeller, a diffuser passage through which compressed air discharged from the compressor impel...

AI Technical Summary

Benefits of technology

The present disclosure provides a compressor housing for a turbocharger that has several technical effects. Firstly, the compressor housing is dividably formed, which makes it easier to assemble and reduces the parts count. Secondly, the refrigerant flow path is sealed at both inner and outer circumferential seals, which prevents deposit accumulation and ensures high supercharging at low cost. Thirdly, the recirculation part formed by the scroll piece and shroud piece prevents reduction of low-speed torque and maintains the operation range on the low airflow-rate side. Finally, the scroll chamber formed by assembling the scroll piece and shroud piece has a circular cross section and improved compression efficiency. Overall, the compressor housing for a turbocharger provides improved performance and prevents deposit accumulation while being cost-effective.

Problems solved by technology

Thus, parts count is indispensably increased, which causes increase in manufacturing cost and reduction in assembling workability.

The cross-sectional shape of the scroll chamber is far different from a circle form accordingly, and such a shape causes reduction in compression efficiency of supplied air.

On the other hand, this method requires long casting cycle, and needs a sand shakeout operation for removing the sand core and an inspection work for checking remaining casting sand.

Meanwhile, the increased flow rate of the compressor impeller and the unfavorable cross sectional shape of the scroll chamber cause reduction of low-speed torque in an engine.

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