摘要 |
A centrifuge has a rotating driving head (2) fixed to a rotating shaft (43), a rotor (3) fixed to the driving head, a means (21) of coupling the driving head and the rotor in rotation, and a means of blocking axial movement on the shaft comprising a means of applying an axial force to a surface (9) of the rotor where the force increases with the rotational speed of the driving head. The means of applying an axial force to the rotor has at least two inertial masses (56) mounted on one end of the driving head symmetrically about its axis of rotation (42). Each mass can be moved between a position unblocking the rotor axially, in which the mass is retracted into the driving head, and a position blocking the rotor axially, depending on the speed of rotation of the head. In this position, the pressing part of the mass extends beyond the external radial surface (49) of the driving head and acts with a ramped surface (11) to a receiving opening (7) on the rotor. This ramped surface is inclined towards the inside of the opening and towards the pressing surface (9) of the rotor. The ramp is conical. At least one mass is held elastically from its retracted position to an initial blocking position. The pressing surface (9) and the holding surface (47) are conical and matched. At least one mass is a shock load to produce a resonant signal during the blocking. An Independent claim is included for a rotor for a centrifuge as above with a receiving opening for at least one end of a driving head, with a surface pressing against the holding surface and at least one ramp which acts with part of a mass, inclined towards the inside from the outside and towards the pressing surface. |