Patent ID: 8336378

Claim:
A method for estimating the moment of inertia of a rotating unit of a washing or washing-and-drying machine; said machine comprising a frame and a washing unit connected to the frame and comprising said rotating unit, which is, in turn, provided with a drum, which is able to house laundry and is mounted within the frame so that said drum is free to rotate about an axis of rotation of its own, and with driving means designed to set said drum in rotation about said axis; said method comprising the steps of: (a) establishing one or more linear parameters, each of which is associated with a corresponding pre-set speed of rotation of said drum, which has a value lower than a sticking-speed threshold corresponding to a minimum speed at which the laundry remains completely stuck to an internal wall of said drum so as to form a single body with the drum; (b) rotating said drum containing the laundry in such a way as to reach at least one of said pre-set speeds of rotation; (c) for each said pre-set speed of rotation, detecting the value of the total torque provided to the rotating unit plus the laundry contained in the drum; (d) estimating the total moment of inertia of the rotating unit plus the laundry contained in the corresponding drum through a linear combination of said torques, detected at each said pre-set speed of rotation, and by using said linear parameters associated to the pre-set speed of rotation itself.