Patent ID: 8337074

Claim:
A stirrer unit comprising: a reaction vessel having an inlet port; and a shaft stirrer including: a stirrer blade, a stirrer shaft connected to the stirrer blade; an adapter having a passage, wherein the adapter is configured to be inserted so as to fit into the inlet port and releasably fastened to the inlet port using a fastening device so that, in a connected state, the stirrer blade and a part of the stirrer shaft is disposed inside the reaction vessel, and wherein, in the connected state, an immersion depth to which the stirrer shaft extends into the reaction vessel is adjustable by adjusting an axial position of the stirrer shaft relative to the adapter; a locking device configured to secure the stirrer shaft in at least two axial positions relative to the adapter that correspond to different immersion depths that are spaced apart from one another; and a spring element configured to secure the locking device in a fixed position.