Dental materials mixing apparatus

Claim 1

APPARATUS FOR STIRRING AND MIXING DENTAL MATERIALS SUCH AS STONE IN A FLEXIBLE BOWL FOR HOLDING THE MATERIALS COMPRISING: A HIGH SPEED IMPELLER COAXIALLY DISPOSED WITHIN THE BOWL IN CONTACT WITH THE MATERIALS; SAID IMPELLER HAVING A PAIR OF BLADES RADIALLY EXTENDING OUTWARDLY FROM A CENTRAL POST; AN UPPER AND A LOWER IMPELLER SECTION COAXIAL WITH RESPECT TO EACH OTHER AND ARRANGED IN FIXED SPACED RELATIONSHIP AND EXTENDING IN PLANES DIAGONALLY DISPOSED WITH RESPECT TO EACH OTHER; SAID PAIR OF BLADES FORMED WITH THE ENDS OF SAID IMPELLER SECTIONS SO THAT SAID BLADES DRIVE THE MATERIAL DOWNWARDLY IN THE DIRECTION OF ROTATION; A LID FOR SAID BOWL HAVING AN ANNULAR INWARDLY SLOPING PERIPHERY ADAPTED TO SEALINGLY ENGAGE WITH THE INTERIOR WALL SURFACE OF THE BOWL AND AN UNDERSURFACE SPACED BY SAID BLADES TO PROVIDE A SUBSTANTIAL GAP THEREBETWEEN; AND POWER MEANS FOR SELECTIVELY ROTATING SAID IMPELLER TO THOROUGHLY MIX THE MATERIAL HELD IN THE BOWL AND TO STIR THE MATERIAL SO AS TO EFFECTIVELY REMOVE THE PRESENCE OF ENTRAPPED AIR IN THE MATERIAL.