Drive rotor for a magnetically coupled pump having tolerance rings

A pump arrangement, comprising:

• a pump casing having an interior space;
• a containment can having a central longitudinal axis and being arranged to hermetically seal a chamber in the interior space;
• an impeller shaft;
• an impeller arranged on an impeller end of the impeller shaft;
• an inner rotor arranged within the containment can on an end of the impeller shaft opposite the impeller end of the impeller shaft;
• b1
• an outer rotor arranged radially outside of the containment can and axially located to interact with the inner rotor,
• a drive motor, and
• a drive shaft arranged to be driven by the drive motor and to be coupled to the outer rotor,
• wherein
• the outer rotor has a hub having a passage bore formed along the central longitudinal axis,
• the passage bore has a hub inner surface having
• an axial groove which extends parallel to the central longitudinal axis, the axial groove being configured to interact with a feather key engaged in a corresponding feather key groove of the drive shaft to rotationally fix the outer rotor with the drive shaft,
• at least one radially encircling first groove and at least one radially encircling second groove,
• tolerance rings are arranged in at least one of the at least one radially encircling first grooves and in the at least one radially encircling second grooves,
• the tolerance rings are configured to prevent radial movement of the outer rotor and the drive shaft relative to one another by elastic deformation,
• when in an installed position the tolerance rings are configured to generate a spring force between the drive shaft and the outer rotor that corresponds to a weight force from the weight of the outer rotor and a centrifugal force generated by an amount of imbalance of the outer rotor, without rotationally fixing the outer rotor to the b2 drive shaft, at least one first groove of the at least one radially encircling first grooves is formed in a first region of the hub inner surface located along the longitudinal axis at least in part between a center of the hub and a first carrier element of the hub, and at least one second groove of the at least one radially encircling second grooves is formed in a second region of the hub inner surface located along the longitudinal axis at least in part between the center of the hub and an end of the hub opposite the first carrier element.