Rotary-Drum Laundry Dryer

Abstract

A rotary-drum laundry dryer ( 1 ) has a revolving drum ( 3 ) structured for housing the laundry to be dried, a hot-air generator ( 6 ) structured to circulate a stream of hot air through said revolving drum ( 3 ), and a lower supporting base or socle ( 9 ) which is structured for resting on the floor and for housing at least part of the hot-air generator ( 6 ). The hot-air generator ( 6 ) in turn comprises: an air recirculating conduit ( 12 ) having its two ends connected to the revolving drum ( 3 ); air circulating means ( 13 ) which are located along the air recirculating conduit ( 12 ) and are structured to produce, inside the air recirculating conduit ( 12 ), an airflow ( 0 which flows through the revolving drum ( 3 ) and over the laundry inside the drum ( 3 ); and at least one heat exchanger ( 15 ) located along the air recirculating conduit ( 12 ) and structured to cool the moist air arriving from the rotatable drum ( 3 ) so to cause the condensation of the surplus moisture inside the airflow (f); a segment ( 12 c) of the air recirculating conduit ( 12 ) extending across the lower supporting base or socle ( 9 ), and being structured so as to house said at least one heat exchanger ( 15 ) of the hot-air generator ( 6 ). The hot-air generator ( 6 ) additionally comprises air filtering means ( 18 ) located along the air recirculating conduit ( 12 ), upstream of said at least one heat exchanger ( 15 ), and a rigid, grid-like protective assembly ( 19 ) which is firmly fixed inside the segment ( 12 c) of the air recirculating conduit ( 12 ), downstream of the filtering assembly ( 18 ) and upstream of the at least one heat exchanger ( 15 ), so as to bar the segment ( 12 c) of the air recirculating conduit ( 12 ) for preventing a generic hard foreign body from reaching the heat exchanger ( 15 ).

1 . A rotary-drum laundry dryer comprising a revolving drum structured for housing the laundry to be dried, a hot-air generator structured to circulate a stream of hot air through said revolving drum, and a lower supporting base or socle which is structured for resting on the floor and for housing at least part of the hot-air generator;
 the hot-air generator in turn comprising: an air recirculating conduit having its two ends connected to the revolving drum; air circulating means which are located along the air recirculating conduit and are structured to produce, inside the air recirculating conduit, an airflow which flows through the revolving drum-and over the laundry inside the drum; at least one heat exchanger located along the air recirculating conduit rand structured to cool the moist air arriving from the rotatable drum so as to cause the condensation of the surplus moisture inside the airflow; and air filtering means located along the air recirculating conduit upstream of said at least one heat exchanger;   a segment of the air recirculating conduit extending across the lower supporting base or socle, and being structured so as to house said at least one heat exchanger of the hot-air generator;   wherein the hot-air generator additionally comprises a rigid, grid-like protective assembly which is unremovably fixed inside said segment of the air recirculating conduit, downstream of the filtering assembly and upstream of the at least one heat exchanger, for protecting said at least one heat exchanger.   
     
     
         2 . A rotary-drum laundry dryer according to  claim 1 , wherein the lower supporting base or socle comprises a lower shell and an upper shell which are structured/shaped for being coupled to one another to form at least the portion of said segment of the air recirculating conduit within which the grid-like protective assembly is located, and said grid-like protective assembly is jammed in between said lower and upper shells. 
     
     
         3 . A rotary-drum laundry dryer according to  claim 1 , wherein said grid-like protective assembly is shaped/dimensioned so as to not significantly slow down the airflow flowing along of the air recirculating conduit. 
     
     
         4 . A rotary-drum laundry dryer according to  claim 3 , wherein said rigid, grid-like protective assembly is shaped/dimensioned so to have a free pass-through area at least equal to 60% of the local air-passage section of the air recirculating conduit. 
     
     
         5 . A rotary-drum laundry dryer according to  claim 4 , wherein said grid-like protective assembly is shaped/dimensioned so to have a free pass-through area at least equal to 75% of the local air-passage section of the air recirculating conduit. 
     
     
         6 . A rotary-drum laundry dryer according to  claim 3 , wherein said grid-like protective assembly is shaped/dimensioned so to have an air-passage free surface ratio at least equal to twice the air-passage free surface ratio of the filtering assembly. 
     
     
         7 . A rotary-drum laundry dryer according to  claim 1 , wherein said grid-like protective assembly comprises a substantially flat, rigid, large-meshed grille. 
     
     
         8 . A rotary-drum laundry dryer according to  claim 7 , wherein said substantially flat, rigid, large-meshed grille is substantially complementary in shape to that of the local air-passage section of the air recirculating conduit. 
     
     
         9 . A rotary-drum laundry dryer according to  claim 1 , wherein the lower supporting base or socle is provided with an access opening which directly communicates with said segment of the air recirculating conduit, upstream of said protective grid-like assembly. 
     
     
         10 . A rotary-drum laundry dryer according to  claim 9 , wherein said air filtering means comprise a manually-removable, air-permeable panel or septum which is arranged inside said segment of the air recirculating conduit, upstream of the protecting grid-like assembly, so as to obstruct the local air-passage section of said segment of the air recirculating conduit, and is structured/dimensioned so as to stop fluff and/or lint particles upstream of said at least one heat exchanger; said manually-removable, air-permeable panel or septum being removable through said access opening realized in the lower supporting base or socle. 
     
     
         11 . A rotary-drum laundry dryer according to  claim 1 , wherein the lower supporting base or socle comprises a lower half-shell structured for resting on the floor, and an upper half-shell stacked up on top of, and rigidly coupled to said lower half-shell; said lower half-shell and upper half-shell being shaped so as to form, when coupled to one another, said segment of the air recirculating conduit which houses said grid-like protective assembly and said at least one heat exchanger of the hot-air generator. 
     
     
         12 . A rotary-drum laundry dryer according to  claim 9 , wherein said grid-like protective assembly is jammed in between said lower and upper half-shells. 
     
     
         13 . A rotary-drum laundry dryer according to  claim 1 , further comprising an upper boxlike cabinet which is rigidly fixed to the top of the lower supporting base or socle and is structured so as to house the revolving drum, and a door which is hinged to said cabinet to rotate to and from a closing position in which said door rests completely against the cabinet to close a corresponding laundry loading/unloading opening; and in that said air filtering means comprise a manually-removable, air-filtering device, which is inserted in easy extractable manner into the inlet of the air recirculating conduit, and is structured to obstruct said inlet to stop fluff and/or lint particles at entrance of the air recirculating conduit; the inlet of the air recirculating conduit being located on the peripheral frame of the cabinet that defines/delimits said laundry loading/unloading opening. 
     
     
         14 . A rotary-drum laundry dryer according to  claim 1 , wherein said air circulating means comprise a centrifugal fan which is located outside of the lower supporting base or socle, substantially at one of the two end-openings of said segment of the air recirculating conduit 
     
     
         15 . A rotary-drum laundry dryer according to  claim 14 , further comprising an electric motor assembly which is mechanically connected to the revolving drum for rotating said drum about its longitudinal axis; said electric motor assembly being fixed on said lower supporting base or socle and the centrifugal fan being mechanically connected to said electric motor assembly. 
     
     
         16 . A rotary drum laundry dryer according to  claim 1 , wherein the hot-air generator is a heat-pump type, hot-air generator which comprises:
 a first air/refrigerant heat exchanger which is located inside said segment of the air recirculating conduit and is structured for rapidly cooling down the airflow arriving from the revolving drum to condense and restrain the surplus moisture in the airflow;   a second air/refrigerant heat exchanger which is located inside said segment of the air recirculating conduit, downstream of the first air/refrigerant heat exchanger, and which is structured for rapidly heating the airflow arriving from the first air/refrigerant heat exchanger and directed back to the revolving drum;   a refrigerant compressing device which is interposed between the refrigerant-outlet of the first air/refrigerant heat exchanger and the refrigerant-inlet of the second air/refrigerant heat exchanger, and which is structured for compressing the gaseous-state refrigerant directed towards the second air/refrigerant heat exchanger; and   a refrigerant expansion device which is interposed between the refrigerant-outlet of the second air/refrigerant heat exchanger and the refrigerant-inlet of the first air/refrigerant heat exchanger, and it is structured so as to cause a rapid expansion of the refrigerant directed towards the first air/refrigerant heat exchanger.   
     
     
         17 . A rotary-drum laundry dryer according to  claim 4 , wherein said grid-like protective assembly is shaped/dimensioned so to have an air-passage free surface ratio at least equal to twice the air-passage free surface ratio of the filtering assembly. 
     
     
         18 . A rotary-drum laundry dryer according to  claim 5 , wherein said grid-like protective assembly is shaped/dimensioned so to have an air-passage free surface ratio at least equal to twice the air-passage free surface ratio of the filtering assembly. 
     
     
         19 . A rotary-drum laundry dryer according to  claim 2 , wherein said grid-like protective assembly comprises a substantially flat, rigid, large-meshed grille. 
     
     
         20 . A rotary-drum laundry dryer according to  claim 3 , wherein said grid-like protective assembly comprises a substantially flat, rigid, large-meshed grille.