Bearing support structure for electro-magnet driven pump

Claim 1

An electromagnetically driven pump comprising: a pump casing having first and second axially spaced end walls where said second wall comprises a substantially magnetically permeable material; a fluid inlet coaxially positioned within said first wall; a fluid outlet in said casing; a rotor unit comprising a motor armature integral with a pump impeller; a magnetic system exterior of said casing adjacent said second wall for providing a rotating magnetic force to rotate said rotor unit; a bearing structure coaxially mounted with respect to said first wall and extending within said casing towards said second wall with the bearing structure comprising a first spherical bearing surface mounted on said rotor unit and a first pillar having a second bearing surface complimentary to said first spherical bearing surface coaxially mounted to said first wall to rotatably support said rotor unit against axial movement towards said first wall under the influence of liquid pressure when said pump is operating; and, a further bearing means associated with said second wall for rotatably supporting said rotor unit and for opposing movement of said unit towards said magnetic system due to the force of magnetic attraction between the magnetic system and said rotor unit with the further bearing means comprising a second pillar having a third spherical bearing surface complimentary to said first spherical surface coaxially mounted with respect to said second wall whereby said second and third complimentary bearing surfaces are engageable with said first spherical surface to rotatably support said rotor unit and resist axial movement of said unit towards said first and second walls.