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Highly efficient, huge torque, countless gear ratios
A transmission based on multi-ratio gear technology

The multi-ratio gear (patent pending) is a new type of involute gear. As it rotates it continuously cycles between two different gear ratios, due to its two halves having different amounts of teeth per unit of rotation. So in essence this gear is already a multi-speed transmission by itself, and without the normally big problem of having to get the gears in phase and sync with each other. This greatly simplifies transmission design and also makes the previously impossible, become possible. For example:

The New-CVT transmission (patent pending) is (almost) as efficient as a single-speed transmission, functionally alike a CVT (meaning it has many gear ratios), suitable for high torque, compact, light and cheap. Its only defects are that it needs to be computer controlled and that drive must be disengaged while changing gear. So while a geared CVT has always been regarded as a unicorn, as well as the holy grail in mechanics, it has now become a reality thanks to the multi-ratio gear.

For electric cars the New-CVT results in longer range, longer battery life, higher battery efficiency, cost reduction and much better performance in demanding conditions.

While for cars with combustion engines it offers both the engine efficiency advantages of a CVT as well as itself being much more efficient than even a manual gearbox. The New-CVT transmission demonstrates the immense potential of the multi-ratio gear.

The multi-ratio gear consists of two gear halves with different amounts of teeth per unit of rotation, and with both halves intermeshing with another gear at the same distance between the axes. In the New-CVT the multi-ratio gears function as intermediate gears in-between single-ratio gears, thereby allowing the intermeshing gears to change gear by simply sliding from one gear to the next. In the New-CVT conical involute, also know as beveloid or tapered, versions of the multi-ratio gear are used to enable sliding at an angle along the gear's axis.

Many versions of the New-CVT are possible, but the most interesting ones use the New-CVT to phase and sync the transmission's main input and output gears that intermesh with a stack of helical bevel gears that are on the same shaft as the main gear in the New-CVT. During gear changes these input and output gears are disengaged. For electric cars not all the single-ratio gears in the New-CVT have counterparts in the stack of helical bevel gears. So for example, a 1:1 to 1:9 New-CVT starting with 8 teeth (all teeth numbers of the counterpart gears are multiplied by a constant to prevent undercutting) has a main gear with 9 gears resulting in 59 unique gear ratios. But if only 3 of these 9 have counterparts for the electric version, then it goes from 1:1 to 1:9 with 7 unique gear ratios. This set-up results in a very compact transmission. So the New-CVT ensures that all the gears are always in phase and sync with each other as to enable gear change, while the efficient and low noise helical bevel gears are the ones actually driving the car and determining the efficiency of the transmission as a whole. So efficiency is mostly due to only three gears intermeshing at any one time, and this can even be reduced to just two gears at the cost of fewer gear ratios. These values are equivalent to the efficiencies of the single-speed transmissions commonly used in electric cars. Cars need to be able to go up a steep slope at slow speed and under heavy load, so designers of single-speed transmissions are forced to choose battery types that are optimised for sustained peak power rather than range, battery life and battery efficiency. Simply using a very big electric motor to solve the problem also requires all the other parts to be a lot bigger. A compact transmission design is meaningless when the actual transmission plus motor is four times the size (weight and cost) it could otherwise be. It is often stated that electric motors have an enormous amount of torque. This is true, but it is also true that the power requirements to make this possible are a major design headache that leads to horrible compromises. That super fast acceleration time is a gimmick that hides a real problem. So for electric cars the New-CVT is a major game changer.



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