The gearbox is obsolete
Many improvements have been made to your car in the past 100 years..... except the gearbox. Its basic principle has not changed. It is still using a series of gear ratios. There is a discontinuity when you move from one ratio to the next whether you do it manually or the car does it for you. It is those gear ratios that make the gearbox obsolete.
Its replacement is the Torque Box. Step on the gas and the Torque Box will get you from zero to top speed in a smooth and continuous way. One speed does it all.
The Torque Box comes with many other advantages:
- The motor can be kept running at constant speed and maximum efficiency
- No switching gears. The output speed can vary from zero to maximum speed without switching gears.
- The system is reversible. Dynamic breaking can be used
- When the output speed goes all the way down to zero the output torque increases indefinitely (bulldozers)
- There is no mechanical speed ratio between the motor and the output. As long as the power of the motor is higher than the losses, the output speed will keep increasing (race cars).
- Less pollution because the motor can be kept running at constant speed.
- Cheaper to manufacture than an automatic transmission.
How the Torque Box works
Patent US 9,109,681 B2 Aug 18, 2015
We start with the usual differential:
The relationship between the three speeds of rotation is: 2Vb = Va + Vc
The next step is to connect two axis (out of three) with a speed variator.
The differential amplifies the speed range of the speed variator
Gear ratio (the two red gears on the right): r
Speed variator's ratio: k
The speed of the shaft C is function of the input speed A: Vc = - r k Va
(The minus sign comes from the 2 gears changing the sense of rotation)
Output speed Vb = Input speed Va * (1-r k) / 2
If r = 1.5 and the speed variator ratio k varies from 0.66 to 2 the output speed varies from zero to 100%.
A car could go from zero to maximum speed without switching gears.
Output torque Tb = 2 Ta/(1- r k)
if r = 1.5 and the ratio of the speed variator gets close to 2/3 the output torque increases indefinitely.
The Torque Box produces a very high starting torque that could be used in bulldozers.
Gear ratio (the two red gears in the center): r
Speed variator's ratio: k
Output speed Vc = Input speed Va *(2rk - 1)
If r = 1.5 and the speed variotor ratio k varies from 2/3 to 2 the output speed varies from 1 to 5 times the input speed. The Torque Box is a 'speed amplifier'.
Output torque Tc = Ta / (2rk -1)
If r = 1.5 and the ratio of the speed variator gets close to 1/3 the output torque increases indefinitely.
The speed range of a car should not be able to go full speed in reverse. The Torque Box will be adapted to the particular application.
Engineers have several parameters at their disposal:
- Many configurations possible
- Which axles will be used as input and output.
- The speed variator can be used with gears and other devices
- The speed range of the speed variator can be adapted to the application.