Multi-row coaxial melt-blown type plant

Abstract

A multi-row coaxial melt-blown type plant ( 1 ) is provided comprising a support ( 2 ) including one or more first conduits ( 20 ) configured to convey polymeric fluid parallel to a dispensing direction ( 2 a ) and at least one second conduit ( 21 ) configured to convey air or gas, a cassette ( 3 ) removably constrained to the support ( 2 ) and including a plurality of acceleration conduits ( 30 ) extending parallel to the dispensing direction ( 2 a ) comprising tubes ( 10 ) in fluid passage connection with one or more first conduits ( 20 ) and configured to distribute the polymeric fluid, first holes ( 31 ) extending parallel to the dispensing direction ( 2 a ), centered and spaced with respect to the acceleration conduits ( 30 ) along the dispensing direction ( 2 a ) and configured to house each part of a respective tube ( 10 ), second holes ( 32 ) extending parallel to the dispensing direction ( 2 a ) and adapted to allow the passage of air or gas, and a slit ( 33 ) extending transversely to the dispensing direction ( 2 a ) between the acceleration conduits ( 30 ) and the first holes ( 31 ) in fluid passage connection with the second holes ( 32 ), wherein the support ( 2 ) comprises a housing ( 22 ) configured to contain the cassette ( 3 ) and the slit ( 33 ) extends in the cassette ( 3 ) from side to side so as to be in fluid passage connection with the second conduit ( 21 ) and configured to convey air or gas from the second conduit ( 21 ) to the second holes ( 32 ).

1 . Multi-row coaxial melt-blown type plant ( 1 ) comprising:
 a distributor ( 2 ) configured to be operatively connected to a cassette ( 10 ) and including
 at least one main access ( 20 )
 adapted to be placed in fluid passage connection with a main conduit ( 10   a ) of said cassette ( 10 ) and 
 adapted to convey polymeric fluid and 
 
 a plurality of secondary accesses ( 21 ) adapted to be placed in fluid passage connection each with a respective secondary conduit ( 10   b ) of said cassette ( 10 ) adapted to convey gas; 
   a dispenser ( 3 ) in fluid passage connection with said distributor ( 2 ), configured to dispense polymeric filaments from said polymeric fluid and including at least:
 a spinneret ( 4 ) adapted to form said polymeric filaments removably constrained to said distributor ( 2 ) and including at least one group ( 4 ′) in turn including:
 a plurality of acceleration conduits ( 40 ) extending parallel to a dispensing direction ( 4   a ) comprising tubes ( 11 ) in fluid passage connection with said at least one main access ( 20 ) and configured to distribute said polymeric fluid, 
 first holes ( 41 ) extending parallel to said dispensing direction ( 4   a ), centered with respect to said acceleration conduits ( 40 ) along said dispensing direction ( 4   a ) and configured to house each part of a respective said tube ( 11 ), 
 second holes ( 42 ) extending parallel to said dispensing direction ( 4   a ) and adapted to allow the passage of air or gas, and 
 a slit ( 43 ) extending transversely to said dispensing direction ( 4   a ) between said acceleration conduits ( 40 ) and said first holes ( 41 ) in fluid passage connection with said second holes ( 42 ), and 
 
 a jig ( 5 )
 adapted to receive said gas to guide said polymeric filaments exiting from said dispenser ( 3 ), removably constrained to one or more of said distributor ( 2 ) and said spinneret ( 4 ) and including, for each of said groups ( 4 ′), a plurality of third holes ( 50 ) centered with respect to said first holes ( 41 ), communicating with said second holes ( 42 ) and configured to house part of said tubes ( 11 ) and to allow, at the same time, the passage of said air or gas around said tubes ( 11 ); 
 
   characterized in that   said spinneret ( 4 ) further comprises one or more chosen from:
 a further said group ( 4 ′) distinct, separate and side by side with the other said group ( 4 ′) and 
 at least one cusp ( 4 ″) side by side with said group ( 4 ′) and comprising at least one main outlet ( 40   a ) configured to convey said polymeric fluid parallel to said dispensing direction ( 4   a ); 
   and in that if there is a cusp ( 4 ″)   said spinneret ( 4 ) further comprises a pair of secondary outlets ( 41   a ) arranged at opposite sides relative to said cusp ( 4 ″) and configured to convey said gas towards said jig ( 5 );   said jig ( 5 ) includes an air blade ( 52 ) defining an outlet ( 52   a ) in fluid passage connection with said secondary outlets ( 41   a ) and developing parallel to said dispensing direction ( 4   a ) at said main outlet ( 40   a ), and   said plant ( 1 ) comprises a transfer device ( 6 ) configured to place in fluid passage connection at least
 a said secondary access ( 21 ) with two opposite ends of said slit ( 43 ) of a said group ( 4 ′) and 
 another said secondary access ( 21 ) with two opposite ends of said slit ( 43 ) of another said group ( 4 ′) or with said pair of secondary outlets ( 41   a ). 
   
     
     
         2 . Plant ( 1 ) according to  claim 1 , wherein said distributor ( 2 ) comprises a plurality of main accesses ( 20 ) and said transfer device ( 6 ) is configured to place in fluid passage connection said main access ( 20 ) with said acceleration conduits ( 40 ) of one said group ( 4 ′) and another said main access ( 20 ) with said acceleration conduits ( 40 ) of another said group ( 4 ′) or with said main outlet ( 40   a ). 
     
     
         3 . Plant ( 1 ) according to  claim 1 , wherein said transfer device ( 6 ) is also configured to place in fluid passage connection said main access ( 20 ) with said acceleration conduits ( 40 ) of each of said group ( 4 ′) and/or said main outlet ( 40   a ). 
     
     
         4 . Plant ( 1 ) according to  claim 3 , wherein said transfer device ( 6 ) comprises at least one main inlet ( 60 ) in fluid passage connection with said main access ( 20 ), a plurality of main branches ( 61 ) all in fluid passage connection with said main inlet ( 60 ) and each with said acceleration conduits ( 40 ) of a respective said group ( 4 ′) and/or a respective said main outlet ( 40   a ), a plurality of secondary inlets ( 62 ) each in fluid passage connection with a respective said secondary access ( 21 ), and a plurality of pairs of secondary branches ( 63 ); wherein in each pair said secondary branches ( 63 ) is in fluid passage connection with a respective said secondary inlet ( 62 ) and each of said secondary branches ( 63 ) is in fluid passage connection with a respective end of said slit ( 43 ) of a said group ( 4 ′) and/or a said secondary outlet ( 41   a ) of a said pair of secondary outlets ( 41   a ). 
     
     
         5 . Plant ( 1 ) according to  claim 1 , wherein said transfer device ( 6 ) is entirely comprised in said distributor ( 2 ), said main inlet ( 60 ) corresponds to said main access ( 20 ), each said secondary inlet ( 62 ) corresponds to a respective said secondary access ( 21 ), and said spinneret ( 4 ) comprises:
 for each said group ( 4 ′), a first main dispensing channel ( 44 ) configured to place in fluid passage connection said main branch ( 61 ) and said acceleration conduits ( 40 ) and a pair of first secondary dispensing channels ( 45 ) each configured to place in fluid passage connection a respective said secondary branch ( 63 ) of a same said pair of secondary branches ( 63 ) with a respective said end of said slit ( 43 ), and/or   for said cusp ( 4 ″), a second main dispensing channel ( 46 ) configured to place in fluid passage connection said main branch ( 61 ) and said main outlet ( 40   a ) and a pair of second secondary dispensing channels ( 47 ); wherein each of said second secondary dispensing channels ( 47 ) is configured to place in fluid passage connection a respective said secondary branch ( 63 ) of a same said pair of secondary branches ( 63 ) with a respective said secondary outlet ( 41   a ) of a same said pair of secondary outlets ( 41   a ).   
     
     
         6 . Plant ( 1 ) according to  claim 5 , wherein said distributor ( 2 ) comprises a support plate and a breaker plate; and wherein said transfer device ( 6 ) is entirely comprised in one or more of said support plate and said breaker plate. 
     
     
         7 . Plant ( 1 ) according to  claim 1 , wherein said distributor ( 2 ) and said dispenser ( 3 ) develop mainly along a longitudinal direction ( 1   b ); wherein each of said main branches ( 61 ) defines a main end ( 61   a ) opposite to said main inlet ( 60 ); wherein each of said secondary branches ( 63 ) defines a secondary end ( 63   a ) opposite to said secondary inlet ( 62 ); and wherein said ends ( 61   a ,  63   a ) are distributed on a longitudinal plane ( 1   c ) parallel to said longitudinal direction ( 1   b ) in such a way that, for each said group ( 4 ′) or said cusp ( 4 ″) and for each set including a said main end ( 61   a ) and a pair of said adjacent secondary ends ( 63   a ), at least said secondary ends ( 63   a ) are mutually misaligned with respect to directions normal to said longitudinal direction ( 1   b ). 
     
     
         8 . Plant ( 1 ) according to  claim 7 , wherein said ends ( 61   a ,  63   a ) are distributed on a longitudinal plane ( 1   c ) in such a way that all said ends ( 61   a ,  63   a ) of the same said group are mutually misaligned with respect to directions normal to said longitudinal direction ( 1   b ). 
     
     
         9 . Plant ( 1 ) according to  claim 7 , wherein for each said group ( 4 ′) or said cusp ( 4 ″) and for each said set, at least one said main end ( 61   a ) and one said secondary end ( 63   a ) are mutually aligned along development directions ( 6   a ) transverse to said main direction (la). 
     
     
         10 . Plant ( 1 ) according to  claim 1 , wherein said spinneret ( 4 ) comprises at least one seat ( 49 ) configured to house at least one filter ( 12 ) and arranged adjacent to said distributor ( 2 ).