Abstract: A solenoid assembly (1) is disclosed, the solenoid having a first electro-magnet (9) for producing a first magnetic field. There is also movable element (3), in the form of a permanent magnet (4), with flux guides (7,8) to distribute the magnetic field, which moves within the magnetic field created by the electro-magnet. A second electro-magnet (11) may also- be included in the solenoid thereby creating a push-pull solenoid. The second electro-magnet is arranged so that its magnetic field acts in the opposite direction to the first electro-magnet by having its coils wound in the opposite direction.

Abstract: An apparatus comprises a rotor supported for rotation about a longitudinal axis. The rotor comprises an elongate tubular member enclosing a substantially cylindrical space, the elongate tubular member having a first open end defining an inlet, and a second open end defining an outlet. The apparatus includes at least one electrically conductive element for generating a magnetic field when electric current flows therethrough and for controlling rotation of the rotor. At least a part of at least one said electrically conductive element is aligned axially with at least a part of said elongate tubular member. The elongate tubular member comprises conveying means adapted so that upon rotation of said rotor, at least one body is caused to move in a direction from said inlet toward said outlet, through the substantially cylindrical space.