MY134721A - Improvements to laboratory mixers - Google Patents

Abstract

A ROTARY MIXER HAS AN ELECTRIC DRIVE MOTOR (2) WHICH DRIVES A LOWER ROTOR (4) AND AN OPTIONAL INTERMEDIATE ROTOR (50) VIA AN DRIVE SHAFT (3). THE MOTOR, PREFERABLY AN AC INDUCTION MOTOR, IS POWERED FROM A VARIABLE FREQUENCY SUPPLY BY WHICH THE SPEED OF THE MOTOR CAN BE VARIED. IN ONE OPTION, SUPPORT ARMS (20) CARRY A BEARING (30) WHICH SUPPORTS THE DISTAL END OF THE DRIVE SHAFT. THE ARMS MAY ALSO SUPPORT AN OPTIONAL STATOR (35) IN A POSITION SURROUNDING THE LOWER ROTOR. CONNECTIONS BETWEEN THE MOTOR, DRIVE SHAFT AND LOWER ROTOR, AND BETWEEN THE MOTOR BODY, SUPPORT ARMS AND BEARING OR STATOR, ARE MADE BY SCREW THREADS (10, 11, 12, 21, 33, 34) TO FACILITATE EASILY ASSEMBLY AND DIS-ASSEMBLY OF THE ''WETTED'' MIXER COMPONENTS WITHOUT THE USE OF TOOLS. IN ONE OPTION, THE LOWER ROTOR HAS BLADES WITH A V-SHAPED TRANSVERSE CROSS-SECTION WHICH CAN CO-OPERATE WITH SIMILARLY V-SHAPED SLITS IN A CYLINDRICAL WALL OF THE OPTIONAL STATOR. IN ANOTHER OPTION, THE LOWER ROTOR HAS A SET OF BLADES WITH EACH BLADE HAVING A CURVED LEADING FACE AND A BEVELLED TRAILING FACE. YET ANOTHER ROTOR HAS A PAIR OF FLAT, MUTUALLY PARALLEL, TOOTHED BLADES THAT ARE SPACED APART AND COAXIALLY MOUNTED ON A COMMON HUB.(FIGURE 6)