Abstract: Magnetic levitation methods and apparatus use arrays of vehicle magnets to provide three forces: suspension, guidance and propulsion. The magnets, which can be permanent magnets or superconducting magnets operating in the persistent current mode, have associated control coils that allow the magnets to provide a controllable attractive force to a laminated steel rail. The control coils adjust the gap between the magnets and the rails so as to be in stable equilibrium without requiring significant power dissipation in the control coils. These same magnets and steel rails also provide lateral guidance to keep the vehicle on the track and steer the vehicle on turns. The suspension control coils can provide lateral damping by means of offset magnets in the suspension arrays. Windings in transverse slots in the steel rails are excited with currents that react against the field produced by the vehicle magnets to create vehicle propulsion.

Abstract: A system is disclosed that controls the power flow to Linear Synchronous Motor (LSM) stators for a vehicle transport system. This invention allows multiple vehicles to operate in close proximity in a guideway without requiring an excessive number of separate controllers. It can be used in conjunction with schemes now in use and is particularly useful in elevator hoistways or for automated people movers near stations.

Abstract: Magnetic levitation methods and apparatus use arrays of vehicle magnets to provide three forces: suspension, guidance and propulsion. The magnets, which can be permanent magnets or superconducting magnets operating in the persistent current mode, have associated control coils that allow the magnets to provide a controllable attractive force to a laminated steel rail. The control coils adjust the gap between the magnets and the rails so as to be in stable equilibrium without requiring significant power dissipation in the control coils. These same magnets and steel rails also provide lateral guidance to keep the vehicle on the track and steer the vehicle on turns. The suspension control coils can provide lateral damping by means of offset magnets in the suspension arrays. Windings in transverse slots in the steel rails are excited with currents that react against the field produced by the vehicle magnets to create vehicle propulsion.

Abstract: Synchronous motors according to the invention operate at higher efficiency, with lower cost, reduced mass and reduced cogging. Magnet dimensions are selected that reduce cogging forces to a negligible amount even though there are fewer slots than normal. Optionally, it is possible to use non-overlapping windings with deeper and open slots. The approach is applicable to both rotary and linear motors and motors using either permanent magnets or electromagnets in the field structure. It is particularly relevant to linear or rotary motors that have a large air gap, and to small motors that must deliver a high ratio of thrust or torque to motor mass.

Abstract: Magnetic levitation methods and apparatus use arrays of vehicle magnets to provide three forces: suspension, guidance and propulsion. The magnets, which can be permanent magnets or superconducting magnets operating in the persistent current mode, have associated control coils that allow the magnets to provide a controllable attractive force to a laminated steel rail. The control coils adjust the gap between the magnets and the rails so as to be in stable equilibrium without requiring significant power dissipation in the control coils. These same magnets and steel rails also provide lateral guidance to keep the vehicle on the track and steer the vehicle on turns. The suspension control coils can provide lateral damping by means of offset magnets in the suspension arrays. Windings in transverse slots in the steel rails are excited with currents that react against the field produced by the vehicle magnets to create vehicle propulsion.

Abstract: Synchronous motors according to the invention operate at higher efficiency, with lower cost, reduced mass and reduced cogging. Magnet dimensions are selected that reduce cogging forces to a negligible amount even though there are fewer slots than normal. Optionally, it is possible to use non-overlapping windings with deeper and open slots. The approach is applicable to both rotary and linear motors and motors using either permanent magnets or electromagnets in the field structure. It is particularly relevant to linear or rotary motors that have a large air gap, and to small motors that must deliver a high ratio of thrust or torque to motor mass.

Abstract: Inductive transfer methods and structures combine, in a single system, at least two of the three functions of transferring power, communicating data, and sensing position with a vehicle on a guideway. A set of conductors is installed on the guideway to inductively couple a multiplicity of diverse signals with a corresponding set of conductors on the vehicle. The vehicle may be moving or stationary, and signals may be coupled in one or both directions. Coupling is effected without direct electrical contact, through a common region or gap, and the structures provide suitable and precise air gap control for the conductors effecting coupling of each signal. In addition, the windings are arranged with a topology and/or symmetry to cancel crosstalk between different signals.

Abstract: A system for guidance and/or switching of a vehicle or other object comprises a guideway, a guide plate that moves along the guideway, and a magnetic field source that induces a magnetic force between the guide plate and at least a portion of the guideway over which the guide plate is moving. The guide plate is attached to the vehicle or coupled to its steering systems. The magnetic force centers the guide plate along the guideway by opposing any lateral deviation from center. The magnetic field source is a permanent magnet, an electromagnet (including a superconducting magnet) or any other known magnetic field source. It is preferably included in, or forms part of, the guide plate. Likewise, the guide rail preferably comprises ferromagnetic or paramagnetic material, i.e., a material that forms a temporary magnet in the presence of the magnetic field of the source.

Abstract: A positioning apparatus for a maglev vehicle includes multiple vehicle magnets. The magnets are paired For a suspension configuration, the magnets are one above the other, with a plurality of pairs arranged along the length of the vehicle. The poles are of adjacent magnets are opposite each other, transverse of the guideway. The guideway carries a conductor that is located symmetrically with respect to the two vehicle magnets. Among other things, the conductor may be a ladder, discrete coils or a helical winding. As the vehicle moves along the guideway, the voltages are induced in the circuits of the guideway conductor by the moving vehicle magnetic fields. If the vehicle is at a symmetry position with respect to the guideway, no current is induced in the guideway conductors because the magnetic fields from the pair of magnets cancel each other.

Abstract: A print wheel comprising a plurality of character elements for use in a serial impact printer such as a typewriter is directly attached to a rotor of a high performance rotary stepper motor. The rotor which is characterized by a high force-to-mass ratio includes a plurality of circumferentially spaced magnetic drive elements which are integrally formed with the rotor hub which also supports the print wheel. In one embodiment, the stator of the rotary motor forms an axial air gap between an active stator portion and an inactive stator portion, and the rotor and print wheel are removably mounted in the air gap. In another embodiment, the stator of the rotary motor forms a radial air gap between the active stator portion and the inactive stator portion.

Abstract: An electronically controlled rotating synchronous machine having armature and field windings on the same magnetically-permeable core. The rotor of the machine is an open tooth structure. The self inductance of the armature and field windings is substantially independent of relative position between the rotor and stator but mutual inductance between the armature and field windings varies with relative position. A rotor position detector senses the voltage in one of the machine windings and relates that voltage to said relative position. Switches are provided to control electric current flow in the armature winding on the basis of the voltage sensed by the detector.

Abstract: A high performance stepper motor comprises a stator having a plurality of pole positions. Each of the pole positions includes a plurality of stator elements or teeth on opposite sides of a stator-to-stator air gap with nonmagnetic material located in the spaces between the extremities of the teeth. Energization means in the form of a plurality of windings adapted to be connected to a multiphased drive source are associated with the stator means at the various pole positions respectively. Motive means comprising a rotor or a slider includes a plurality of motive elements which comprise teeth or slugs. In order to achieve low inertia and a high force-to-mass ratio, the motive means is located within and confined to the air gap of the stator.

Abstract: A high performance stepper motor comprises a stator having a plurality of pole positions. Each of the pole positions includes a plurality of stator elements or teeth on opposite sides of a stator-to-stator air gap with nonmagnetic material located in the spaces between the extremities of the teeth. Energization means in the form of a plurality of windings adapted to be connected to a multiphased drive source are associated with the stator means at the various pole positions respectively. Motive means comprising a rotor or a slider includes a plurality of motive elements which comprise teeth or slugs. In order to further achieve low inertia and a high force-to-mass ratio of the passive means, the motive means comprises discontinuities in the magnetic material thereof including nonmagnetic material between the extremities of the motive elements so as to reduce flux leakage in the direction of movement of the passive means through the air gap while simultaneously reducing the mass of the motive means.

Abstract: A serial impact printing element is mounted on the slider of a high performance linear stepper motor. The slider moves through the stator-to-stator air gap of the linear motor stator comprising an active stator portion having windings associated therewith and a passive stator portion without windings. In order to achieve high performance of the motor, the slider is relatively short as compared with the stator, and longitudinal flux leakage through and the weight of the slider are minimized by the use of nonmagnetic discontinuities therein. The impact printing element includes a wheel having a plurality of circumferentially spaced character elements which are rotated to the printing position by means of a rotary stepper motor.