It is rare to come up with a new idea in the automotive industry that has not been tried before, but the design of a multi-speed gearbox with sprocket gears is one of those rare ideas that was recently patented by the famous Canadian company Inmotive.
Anthony Wong, the company’s chief technical officer who is a cycling enthusiast, began to ponder how to shift gears on bicycles and asked himself what would happen if he put the gears inside a chain sheath. it fell.
The result of his research is a completely new gear system designed for electric vehicles and is expected to perform similarly to current helical gears in single-speed gearboxes of electric motors.
Inmotive claims that by using this mechanism and structure, the range of motion of electric vehicles will increase by about 7 to 15 percent and the acceleration of the vehicle will improve by about 15 percent.
This gearbox is called Ingear, but it is not a CVT (variable gear ratio) gearbox and does not require a gear coordinator. All of this has been replaced by a quiet, highly durable Borg Warner’s chain that not only produces less noise but also transmits high torque to the electric motor.
Gearboxes used in electric vehicles use two gears and the power is transmitted to the wheels by a conventional differential.
But the Ingear gearbox no longer has a second gear and is surrounded by a differential, so there is no need for extra space to put the second gear.
In this type of gearbox, the force is transferred by the chain from one chain wheel to the next chain wheel.
Another sprocket wheel is used as the idler wheel in this mechanism to form a triangular chain.
The sprocket consists of two parts and inside the larger gear with the lower gear is a small gear with a large number of gears.
Larger gears with lower gears are capable of moving transversely to deviate from the chain path.
By moving the larger gear with the lower gear, it is possible for the small gear to engage with the high gear, as if the gear were suddenly changed as the chain rotation speed increases after the small gear engages.
This also happens with dual-clutch and CVT gearboxes, but the mechanism of this gearbox is designed in a simpler and more efficient way.
By changing gears, the electric motor must increase or decrease the speed to synchronize with the gearbox to allow power transmission between the two sprocket wheels.
All of this can be customized using the software. Different sport or comfortable modes can be designed for this gearbox.
In practice, it takes less than a few milliseconds to switch between two sprockets, and this happens in less than one spin of the wheel.
Wong initially designed the prototype gearbox using a few extra pieces and CNC machining. He was able to simulate shifting at 1200 rpm using the same simple, original gearbox.
Inmotive’s chief engineer discarded half of the original design parts to commercialize the invention because it needed to be simplified as much as possible for commercialization.
If the gearbox is mass-produced for automakers, each gearbox will be worth ۸ 108. There is also the ability to install in different dimensions for different types of vehicles. The prototype is currently installed on an electric Kia Soul.