Patent ID: 9097462
Filing Date: 2015-08-04
Classification: D06F,F26B,Y02B

Abstract:
1. A laundry drier comprising an outer box casing, a laundry drum which is located in axially rotating manner inside the casing to rotate about an longitudinal axis, and a closed circuit hot-air generator for circulating a stream of hot air inside said laundry drum; said closed circuit hot-air generator comprising: an air recirculating conduit connected at both ends to laundry drum so that to form the closed circuit; a centrifugal fan located along said air recirculating conduit to produce, inside the latter, an airflow flowing through the laundry drum; heat-pump means comprising a first and second air/refrigerant heat exchangers located into the air recirculating conduit to rapidly cool the airflow coming out from the laundry drum for condensing the surplus moisture in said airflow, and, respectively, to heat the airflow returning back into said laundry drum; the laundry drier further comprising: an electric motor which is designed to simultaneously rotate both said centrifugal fan and said laundry drum through transmission system means; said laundry drier further comprising electronic control means for controlling the speed of the electric motor and configured to: receive a predetermined speed which is associated with a nominal airflow rate within the air recirculating conduit and to a nominal drum speed; said nominal airflow rate and nominal drum speed being both related to a drying program selected by a user; and control the electric motor so that the output motor speed is maintained substantially equal to said predetermined speed, independently of decreasing of the airflow rate caused by clogging-up of particles within said first and/or second air/refrigerant heat exchangers of the said heat-pump means.