This invention relates to a pulse hub motor with power coils tilted and arranged in layers, in up to three dimensions.
The problem to solve was how to create a more powerful, efficient, and flexible pulse hub motor that could not only propel a vehicle, but was capable of collecting power and recharging the batteries not just in braking, but in normal use too.
To solve these problems, the present invention proposes a pulse hub motor comprising a stator that is fixed to a vehicle body, containing many coils arranged in 1 to n columns on the x axis, 1 to n rows on the y axis, and 1 to n extrusion layers on the z axis. Through the centre of the stator is a shaft that can rotate on a bearing. Attached to the shaft is a fixing plate onto which the rotor is bolted. The rotor makes up the outer part of the vehicle wheel, including rim and tyre.
Inside the rotor, magnets are fixed to the inner wheel rim and also to 1 to n extrusions through the z axis, arranged in such a way that they intertwine with the extrusions on the z axis of the stator, although the stator and rotor extrusions never actually make physical contact. Magnets are spaced to align with every other stator coil, and they are offset down the z axis layers such that the coils both push one layer of magnets whilst simultaneously pulling at another layer. Each layer of coils and magnets work together to produce thrust, and coils are fixed in place tilted by up to 10 degrees for stronger directional bias.
The coils of the x axis on the stator are arranged in a staggered format to facilitate a smoother drive motion.
Circuits are created such that every other coil on the y axis are pulsed together, along with the corresponding every other coil on the x axis. Coils on the next z axis layer inward are fired on the same pulse, however the coil that is fired is offset according to the active y axis coil.
Circuits are designed such that in normal drive, but lower power requirement situations such as a cruise or going downhill then parts of the x, y or z configuration can be switched off and can collect power as the magnets driven by the active coils pass over them.
Power can also be collected by the circuits as back-EMF from the collapsing magnetic fields of the coils.
Braking is achieved by reversing the polarity of the current to the coils. As with the driving scenario, light braking is controlled to use only the required x, y and z elements, with the redundant coils collecting power. Once stationary the parking brake should be applied.
Reverse is achieved by reversing the polarity of the current to the coils.
Control over which circuits are active will be maintained by a microcontroller. A microcontroller will also control the timing and power of pulses when at low speeds. At higher speeds the microcontroller will still control the power of each pulse, but the timing will be maintained by a transistor for each circuit, being activated by power from the magnets moving over a bifilar winding on a single coil in each circuit.
A parking/emergency brake mechanism is fitted beside the rotor fixing plate.
In conventional drive systems where thrust is delivered through the central shaft, a larger wheel is a disadvantage. The reverse applies with the motor in this invention wherein a larger wheel means more available thrust. Vehicle design should take this into account.
As a feature of this design is customisation, the number of circuits and therefore phases can be increased or decreased by adding or removing columns in the x axis. For demonstration purposes, the invention will now be described by way of a 4 phase example and with reference to the accompanying drawings in which:
In
If practical, more layers and magnets can be added.
This process is replicated in each of the columns of the x axis. As coil columns in the x axis are purposefully offset with their neighbours (
Coils can recycle energy from the movement of the rotor in both normal drive mode and braking mode by skipping phases if they are not required at that time.
The pulse hub motor mechanism is made possible by taking the stator (100 in
The completed assembly produces the wheel in
Number | Date | Country | Kind |
---|---|---|---|
1602859.9 | Feb 2016 | GB | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/IB2017/050933 | 2/18/2017 | WO | 00 |