Operating Machine, in Particular a Motor-Driven Pump with an Axial Motor Arrangement

Abstract

The present invention refers to an operating machine, in particular a motor-driven pump with an axial motor arrangement, comprising a rotor assembly ( 18 ) and a stator assembly ( 7 ). The rotor assembly ( 18 ) includes an impeller ( 4 ) and a permanent-magnet rotor ( 5 ) firmly associated to the impeller ( 4 ). The stator assembly ( 7 ) includes a single multipolar stator ( 8, 9, 10 ) interacting with the rotor ( 5 ) to impart a rotary motion to the impeller ( 4 ) along an axis (A) perpendicular to the rotor ( 5 ). The rotor assembly ( 18 ) is rotatably supported by a flange ( 6 ) adapted to separate the rotor assembly ( 18 ) from the stator assembly ( 7 ). Guide means ( 16, 17 ) are provided between the rotor assembly ( 18 ) and the flange ( 6 ) to guide the rotary motion of the impeller ( 4 ) about the axis (A).

1 . Operating machine, in particular a motor-driven pump with an axial motor arrangement, comprising a rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) and a stator assembly ( 7 ;  7 A;  7 B;  7 C;  7 D;  7 E;  7 F), said rotor assembly including an impeller ( 4 ;  4 A;  4 B;  4 C;  4 D;  4 E;  4 F) and a permanent-magnet rotor ( 5 ;  5 A;  5 B;  5 C;  5 D;  5 E;  5 F) firmly associated to said impeller ( 4 ;  4 A;  4 B;  4 C;  4 D;  4 E;  4 F), characterized in that said stator assembly ( 7 ;  7 A;  7 B;  7 C;  7 D;  7 E;  7 F) includes a single multipolar stator ( 8 ,  9 ,  10 ;  10 A;  8 B,  9 B,  10 B;  8 C,  9 C,  10 C;  8 D,  9 D,  10 D;  8 E,  8 ′E,  9 E,  10 E, I CE;  8 F,  9 F,  10 F) interacting with said rotor ( 5 ;  5 A;  5 B;  5 C;  5 D;  5 E;
   5 F) to impart a rotary motion to said impeller ( 4 ;  4 A;  4 B;  4 C;  4 D;  4 E;  4 F) along an axis (A) perpendicular to said rotor ( 5 ;  5 A;  5 B;  5 C;  5 D;  5 E;  5 F), said rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) being rotatably supported by a flange ( 6 ;  6 A;  6 B;  6 C;  6 D;  6 E;  6 F) adapted to separate said rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) from said stator assembly ( 7 ;  7 A;  7 B;  7 C;  7 D;  7 E;  7 F), guide means ( 16 ,  17 ;  16 A;  16 B,  17 B;  16 C;  16 D;  16 E;  24 F,  29 F) being provided between said rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) and said flange ( 6 ;  6 A;  6 B;  6 C;  6 D;  6 E;  6 F) to guide the rotary motion of said impeller ( 4 ;  4 A;  4 B;  4 C;  4 D;  4 E;  4 F) about said axis (A). 
 
     
     
         2 . Operating machine according to  claim 1 , wherein said guide means ( 16 ,  17 ;  16 A;  16 B,  17 B;  16 C;  16 D;  16 E;  24 F,  29 F) extend longitudinally along said axis (A) perpendicular to said rotor ( 5 ;  5 A;  5 B;  5 C;  5 D;  5 E;  5 F) leaving substantially free a central region of said stator assembly ( 7 ;  7 A;  7 B;  7 C;  7 D;  7 E;  7 F). 
     
     
         3 . Operating machine according to  claim 2 , wherein said guide means ( 16 ,  17 ;  16 A;  16 B,  17 B;  16 C;  16 D;  16 E) extend along said axis (A) protruding from said flange ( 6 ;  6 A;  6 B;  6 C;  6 D;  6 E) and said rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) towards said stator assembly ( 7 ;  7 A;  7 B;  7 C;  7 D;  7 E) substantially up to a region defined by an upper portion of said multipolar stator ( 8 ,  9 ,  10 ;  10 A;  8 B,  9 B,  10 B;  8 C,  9 C,  10 C;  8 D,  9 D,  10 D;  8 E,  8 ′E,  9 E,  10 E,  10 ′E). 
     
     
         4 . Operating machine according to  claim 3 , wherein said guide means ( 16 ,  17 ) comprise a circular groove ( 16 ) provided on said flange ( 6 ) and adapted to engage a corresponding circular rim ( 17 ) extending from said impeller ( 4 ) towards said flange ( 6 ). 
     
     
         5 . Operating machine according to  claim 4 , wherein said circular groove ( 16 ) is obtained in one piece with said flange ( 6 ) and said circular rim ( 17 ) is obtained in one piece with said impeller ( 4 ). 
     
     
         6 . Operating machine according to  claim 2 , wherein said guide means ( 24 F,  29 F) extend along said axis (A) from a central region of said flange ( 6 F) and said rotor assembly ( 18 F) towards an upper portion of said impeller ( 4 F). 
     
     
         7 . Operating machine according to  claim 6 , wherein said guide means comprise a pin ( 24 F) extending from a central region of said flange ( 6 F) and adapted to engage a corresponding recess ( 29 F) in said impeller ( 4 F), said recess ( 29 F) extending from a central base portion of said impeller ( 4 F) towards said upper portion of said impeller ( 4 F). 
     
     
         8 . Operating machine according to  claim 7 , wherein antifriction means ( 26 F,  27 F) are interposed between said pin ( 24 F) and said recess ( 29 F). 
     
     
         9 . Operating machine according to  claim 7 , wherein said pin ( 24 F) is obtained in one piece with said flange ( 6 F). 
     
     
         10 . Operating machine according to  claim 1 , wherein said impeller ( 4 ) is formed by overmoulding onto said rotor ( 5 ). 
     
     
         11 . Operating machine according to  claim 1 , wherein said said rotor ( 5 B) is firmly joined with said impeller ( 4 B). 
     
     
         12 . Operating machine according to  claim 3 , wherein said guide means ( 16 B,  17 B) comprise a circular groove ( 16 B) provided on said flange ( 6 B) and adapted to engage a corresponding circular rim ( 17 B) extending from said rotor ( 5 B) towards said flange ( 6 B). 
     
     
         13 . Operating machine according to  claim 1 , wherein said rotor ( 5 ;  5 A;  5 B;  5 C;  5 D;  5 E;  5 F) is axially magnetized. 
     
     
         14 . Operating machine according to  claim 1 , wherein said multipolar stator comprises a plurality of magnetic poles ( 8 ;  8 B;  8 C;  8 F) connected to a yoke ( 9 ;  9 B;  9 C;  9 F) and a plurality of stator coils ( 10 ;  1  OB;  10 C;  10 F), each stator coil of said plurality of stator coils ( 10 ;  10 B;  10 C;  10 F) being wound round a respective magnetic pole of said plurality of magnetic poles ( 8 ;  8 B;  8 C;  8 F). 
     
     
         15 . Operating machine according to  claim 1 , wherein said multipolar stator comprises a plurality of stator coils ( 10 A), each stator coil of said plurality of stator coils ( 10 A) being wound to form a respective magnetic pole. 
     
     
         16 . Operating machine according to  claim 1 , wherein said multipolar stator comprises at least one stator coil ( 10 D;  10 E,  10 ′E) at least partially enclosed by a plurality of magnetic poles ( 8 D;  8 E,  8 ′E) that close up in an alternate sequence on the upper side of said at least one stator coil ( 10 D;  10 E,  10 ′E) to form a respective plurality of alternate patterns of north and south poles. 
     
     
         17 . Operating machine according to  claim 16 , wherein said multipolar stator comprises at least a first stator coil ( 10 E) and a second stator coil ( 10 ′E), said first stator coil ( 10 E) and second stator coil ( 10 ′E) being at least partially enclosed by a first plurality of magnetic poles ( 8 E) and a second plurality of magnetic poles ( 8 ′E), respectively, said first stator coil ( 10 E) and said second stator coil ( 10 ′E) and, respectively, said first plurality of magnetic poles ( 8 E) and said second plurality of magnetic poles ( 8 ′E) being concentrically arranged relative to each other. 
     
     
         18 . Operating machine according to  claim 1 , wherein said rotor assembly ( 18 ;  18 A;  18 B;  18 C;  18 D;  18 E;  18 F) is contained in a diffuser ( 1  ; 1 A;  1  B;  1  C;  1  D;  1  E;  1  F) provided with an inflow aperture ( 2 ;  2 A;  2 B;  2 C;  2 D;  2 E;  2 F) and at least one outflow aperture ( 3 ;  3 A;  3 B;  3 C;  3 D;  3 E;  3 F), said diffuser ( 1  ;  1 A;  1  B;  1  C;  1  D;  1  E;  1  F) being sealingly connected to said flange ( 6 ;  6 A;  6 B;  6 C;  6 D;  6 E;  6 F). 
     
     
         19 . Operating machine according to  claim 18 , wherein at least one heating element ( 20 ) is associable to said diffuser ( 1  C). 
     
     
         20 . Operating machine according to  claim 19 , wherein said heating element ( 20 ) is wound either inside or outside on said diffuser ( 1  C) or incorporated therein.