Aalborg Universitet

Gm Global Technolgoy Operations, Inc.

Aalborg University

Peter Omand Rasmussen

Rasmus Koldborg Holm

Nick Ilso Berg

Klaus Trangbaek

Vladimir Suplin

The present invention relates to an actuator system with a magnetic lead screw, comprises a magnetic rotor and a translator cylinder, the translator cylinder comprises a magnetic stator, the translator cylinder has a closed first end and a second end confined by a lid, the lid having a shaft opening for a shaft coupled to the magnetic rotor, wherein the magnetic rotor, when inserted in the translator cylinder, is arranged to translate a linear movement of the translator cylinder into a rotational movement of the magnetic rotor by using magnetic flux interacting between the magnetic stator and the magnetic rotor, said rotational movements is being transferred through a shaft, the lid with a shaft opening arranged for receiving the shaft, wherein the shaft is arranged to make both the linear and the rotational movement in the shaft opening, the lid being arranged for confining the second end of the translator cylinder, the translator cylinder confined by the lid forms, when divided by the magnetic rotor, a first chamber with a first volume and a second chamber with a second volume, wherein the first volume and the second volume changes as a function of the linear movement. The invention also relates to a method of operating an actuator system with a magnetic lead screw.

Actuator system with dual chambers

An apparatus for controlling force of a magnetic lead screw actuator includes a magnetic lead screw actuator, an external control module and at least one sensor device integrated within the magnetic lead screw actuator. The magnetic lead screw actuator includes an electric machine, a rotor, and a translator. The rotor includes a rotor magnet assembly forming first helical magnetic threads along the rotor and the translator includes a translator magnet assembly forming second helical magnetic threads along the translator. Rotation of the rotor by the electric machine effects linear translation of the translator by interaction of the first and second helical magnetic threads. The external control module is electrically operatively coupled to an electric machine controller of the magnetic lead screw actuator. The at least one sensor device integrated within the magnetic lead screw actuator is configured to measure a parameter indicative of a relative displacement between the rotor and the translator and this parameter is provided as feedback to the electric machine controller.

Method and apparatus for measurement and control of linear actuator

In order to improve the torque per weight ratio in electrical machines for a lower price it is proposed to use a segmented stator design. The segmented stator design is based on general E shaped cores traditionally used for single-phased transformers and inductors, The E-cores has a coil around the centered leg and is assembled parallel to the rotor axis, which means it will function with the transverse flux principle. A radial flux principle can also be performed with the E-cores if the E-cores are divided into two U-sections with a full pitch winding in between them. A clear extra advantage with the E-cores is short flux paths meaning less steel has to be magnetised. For a low volume production standard E-cores can be used making the investment in production facilities smaller. The E-core machines using the transverse principle can have different pole-shapes such the normal force between the rotor and stator are significantly reduced. This makes unequal designs like a 3 stator- and 2 rotor-pole design practical possible.

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Norresundby, Denmark

Peter Omand Rasmussen