Patent ID: 7723934

Claim:
A control method of an automatic cleaning device of an submerged surface in liquid comprising: a chassis carrying a device for filtration of the liquid; units for driving of the chassis on the submerged surface to be cleaned; drive motor means of the chassis on the submerged surface comprising at least one electric drive motor of the chassis on the submerged surface, supported by the chassis and arranged to transmit motor movement to at least part of the units for driving of the chassis on the submerged surface; electronic supply and control means of each electric drive motor of the chassis on the submerged surface, adapted to be able to control reversal of the drive direction of the units for driving of the chassis on the submerged surface, wherein: at least one electric variable providing a value representative of the load torque of the at least one electric drive motor arranged to transmit motor movement to at least part of the units for driving of the chassis on the submerged surface is measured periodically; each value obtained at a predetermined threshold value representative of a maximum acceptable value is compared, and in the event where said threshold value is exceeded for at least one electric drive motor of the chassis on the submerged surface, a procedure is triggered, said saving procedure, in which: control at least of this or these electric drive motors of the chassis on the submerged surface is reversed so as to engender displacement of the device in a direction opposite its direction of initial displacement; and displacements of the device are controlled, suitable for having it follow a trajectory enabling it to deviate from the initial trajectory it was following when said threshold value was exceeded.