Turbocharger in a combustion engine

The device has a turbine (5), driving a compressor (3), and a bypass (15) to a compressor rotor (8). The active flow cross-section of the bypass is adjusted by a shut-off part, located in a flow aperture (18), which connects the bypass to the compressor exhaust flow section. The section is formed by a spiral channel (14) of the compressor. The shut-off device is formed as a translatory closeable shut-off valve (19), adjusted by a pneumatic actuator (20).