Electric motor vehicle

Abstract

Various embodiments include an electric motor vehicle which does not have any active suspension components, gearbox, differential or other mechanical transmission components, in various embodiments including consists a chassis, at least one pair of integrated wheel and brushless DC electric motor assemblies mounted on the chassis with conventional suspension components including springs and dampers. In various embodiments, a battery pack on the chassis provides power to the integrated wheel and electric motor assemblies; and a control system operates each integrated wheel and motor assembly independently of each other integrated wheel and motor assembly. Various embodiments include the control system including a master controller connected to the battery pack, and, a separate slave controller connected to the battery pack and to each of the integrated wheel and motor assemblies as well as the master controller.

Description

PRIORITY CLAIM TO RELATED APPLICATIONS[0001]This application is a national stage application under 35 U.S.C. §371 of PCT / AU2009 / 001359, filed Oct. 16, 2009, and published as WO 2010 / 042989 A9 on Apr. 22, 2010, which claims priority to Australian Application No. 2008905352, filed Oct. 16, 2008, which applications and publication are incorporated herein by reference and made a part hereof in their entirety, and the benefit of priority of each of which is claimed herein.TECHNICAL FIELD[0002]This invention relates to electric motor vehicles and more particularly to low speed electric motor vehicles suitable for use as resort cars or golf cars.BACKGROUND ART[0003]Prior art electrical vehicles typically incorporate a brushed motor gearbox train and require a substantial bank of batteries in order to operate. The use of a gearbox train to transfer the power from the motor to the four wheels causes losses in efficiency. Sometimes as much as 50% of the power input to the electric motor is lo...

AI Technical Summary

Benefits of technology

[0081]Many benefits are provided by the electric vehicle of the invention and these include four wheel drive and front wheel drive which makes the vehicle less damaging to golf courses in wet weather and more able to be used in general resort activities where quality turf and car-paths are not available. There is also freedom of design and the removal of the motor, batteries and transmission from under the seat of conventional golf carts permits a short wheel base car to carry four forward facing passengers.

Problems solved by technology

The use of a gearbox train to transfer the power from the motor to the four wheels causes losses in efficiency.

Whilst these in-wheel electric motor vehicles have lower power losses and are more efficient, these vehicles have associated with them, the problem of poor road holding performance.

The reason these vehicles perform badly on the road is a result of increases in their so-called “un-sprung mass”.

As the un-sprung mass of a vehicle increases, the contact force of a tyre fluctuates when the vehicle runs over an uneven road, resulting in deteriorated road holding properties.

Firstly the sprung mass of the vehicle decreases as the motor and transmission which originally sat on a suspended chassis is taken off the chassis.

Secondly, since the motor stator of the in-wheel motor is rotatably fixed to a spindle shaft connected to a part called an “upright” or “knuckle” which is one of the parts around the wheels of the vehicle, the un-sprung mass of the vehicle increases when an in-wheel motor is mounted, thereby deteriorating the road holding properties of the vehicle.

As a result of the large un-sprung masses associated with in-wheel electric motors, the road holding performance, and consequently safety, of these vehicles is seriously compromised.

Even when the mass of the body of a vehicle, so-called “sprung mass” is small, the road holding properties of such vehicles deteriorates when in-wheel electric motors are used.

However, the way in which the inventor has done this is to introduce very complicated and sophisticated active suspension components that constantly monitor pressures exerted on the wheels by the terrain and by the suspended chassis to compensate for the differences in pressures through the use of active suspension components.

Such an approach adds complexity and raises the cost to manufacture in-wheel electric vehicles.

The problems caused by un-sprung mass result in the introduction of variable force between the wheel and the ground.

This can result in wheels locking under braking or spinning even under minimal acceleration and especially under strong acceleration.

This locking and spinning contributes further to the poor road-holding experienced in the general motor vehicle industry.

Golf course or resort vehicles are fairly small in dimension, and often lack components such as a roof, windows and doors.