EXHAUST-GAS DRIVEN TURBOCHARGER HAVING TWO STAGES

摘要

A two-stage exhaust-driven supercharger aggregate is disclosed which comprises a low-pressure supercharger and a high-pressure supercharger. Each of the two superchargers is provided with a compressor driven by a respective turbine. Each of these superchargers is arranged on a separate shaft. In order to provide sufficient space for auxiliary components such as supercharger-air coolers, a bypass system and the like, and to obtain one compact structural unit, the pressure ratio of the low-pressure compressor is made greater than the pressure ratio of the high-pressure compressor by at least 40%. In this way, the geometrical exterior dimensions of the high-pressure supercharger becomes substantially smaller than the dimensions of the low-pressure supercharger. The shaft of the high-pressure supercharger is arranged such that it is parallel to, and offset laterally relative to the shaft of the low-pressure supercharger. Due to the smaller size of the high-pressure supercharger at least a portion of the auxiliary components are arranged in a radial direction next to the high-pressure supercharger without extending beyond an enveloping profile of the low-pressure supercharger. By the present invention, a very compact exhaust-driven supercharger aggregate is formed.