Patent ID: 8918936

Claim:
A method of sensing the motion of a wash assembly due to a dynamic unbalance of a wash laundry drum assembly in a washing machine comprising a casing and the wash assembly which comprises a tub connected in a floating manner to said casing and the laundry drum assembly; said laundry drum assembly comprising a laundry drum mounted to rotate freely about a longitudinal axis of rotation inside said tub and means for rotating said laundry drum about said axis of rotation; said method comprising the steps of: a) increasing the rotation speed (ω) of said laundry drum to a first rotation speed (ω DIST ) at which the laundry adheres, in a fixed distribution pattern, to the inner wall of said laundry drum; b) determining, when said first rotation speed (ω DIST ) is reached, a first parameter related to a time pattern of the values of an unbalance function A=T−Jdω/dt filtered at a predetermined filtration frequency; T and ω being the torque and rotation speed, respectively, imparted to said laundry drum, and J being the moment of inertia of said laundry drum assembly; c) as of said first rotation speed (ω DIST ), repeatedly increasing the rotation speed (ω) of the laundry drum by a predetermined value (Δω) to cover a predetermined resonance rotation speed range (D FR ) of the wash assembly; d) determining, at each increase (Δω) in rotation speed (ω) within said predetermined resonance rotation speed range (D FR ), a second parameter related to the time pattern of the values of said unbalance function A=T−Jdω/dt filtered at said predetermined filtration frequency; e) calculating a difference between said second parameter and said first parameter; f) determining a dynamic unbalance parameter related to the dynamic unbalance torque of said laundry drum assembly as a function of said difference.