Diffrunner concept

[lincpimp]

Ok, place the magnets on the outside of the diff case, and use a oversized can with the windings on the inside as an inrunner does. The can would be solidly mounted and the "diff/stator" would ride on bearings that are suppored by the ends of the can. In reality the endbells of the can could be made as bulkheads, and the center of the can would be removeable with the windings attached. 1/4 turn design would make removing one endbell easy, just pull the 4 chassis mount screws (2 in each bulk) turn 1 bulk 90deg and remove the stator/diff. Have one end of this stator/diff unbolt and you can service the diff as easily as a regular diff. Solidly mount the other bulkhead to the can, maybe with screws. This would allow kv chages easily, as only the center section of the can would need to be removed, or make it completely modular like a novak motor.

Multipole woould be required, and the diff height would be taller, as would the center drives. Worm drive ft and rear diffs with top output and bevel gears (think dump truck axles) would allow for more reduction and higher center driveline angles without raising weight too much. Place the rx/servos below them to offset this. Chassis could be narrow due to center motor mount and saddle syle trays with lipos split into series packs. Center motor/diff could also be placed front or rear for desired weight bias.

Aside from the added complexity of the center section and multi gear diff assemblies it would offer alot of benefits. Solidly made al or fiber reinfored plastic (carbon fiber?) front and rear diff bulks would be required to keep the worm drives meshing well. Off power coating would not be doable, unless you use one way bearings between the diffs and the wheels. Or you could use a gear reduction with std gears in the diffs, with a bevel output to direct the flow back to the center assembly. Seeing as these could be made smaller, and sealed it would be better than a center diff with exposed gears, even though it is more complex.

Of course a reduction could be applied to each end of the center assembly's outputs, and sealed. This would aloow std front and rear diffs and still not wear like an exposed setup. Gears could be spiral cut to improve effecintcy and strength and thus be made smaller. Still more complex that what we currently run.

[zeropointbug]

Yeah man! Great idea, maybe not doable any time soon with our R&D access, but doable. Although, I am not too keen on using warm gears for anything R/C however, I just don't like them. This idea though having the diff being physically built into the motor housing is awesome, and on each end of the chassis you are saying? I don't think you would even need warm gears, as you can really do anything with motors, increase torque, lower speed, yada, yada.

Sike, ya, I think a sufficiently thick alum. plate screwed to diff housing then if the motor shaft was keyed, or squared, or splined..... then it would just slide in and be supported by the motor shaft, which because of the fact that it would be over sized from the increased size hollow shaft then it would be fine maybe.