Current Technology: Toothed-wheel Gears and Worm Gears
Toothed-wheel drives have been in use for several hundred years. For a long time it was enough to make sure that the teeth on the two wheels do not clash; this has been achieved by using identical separation and non-interfering shapes for the teeth on the two wheels. Later the need has arisen to keep the angular velocity of the two wheels constant in time; this has been achieved by using specially shaped tooth profiles such as evolvents and cycloids. A typical evolvent profile is shown in the figure below.
However, the surfaces of the two coupling teeth keep sliding on one another - except in the position when the contact point between the two teeth just touches on the line connecting the centres of the two wheels. In the case of twisted-teeth gears and also of screw gears and worm gears, the teeth are not only sliding on one another radially but also axially i.e. along their length. This introduces very strong friction between the teeth reducing significantly the energy efficiency and also causing overheating and abrasion and ultimately reduced lifetime. The figure below depicts a worm gear arrangement.
Another major disadvantage of the conventional toothed-wheel drives is that back-lash cannot be eliminated completely or it is very difficult to do. Unlike in the case of roller gears pushing the wheels against each other does not work because that would jam the teeth and the wheels and seize movements. This is simply impossible to do in conventional gears due to their very basic geometry and structure.
New Technology: Roller Gears
In our new patent-protected roller gearing and transmission mechanism we use rollers to couple the motion of the driving and the driven bodies. The rollers are embraced by two corresponding grooves developed onto the surfaces of the two bodies and as the driving body moves the rollers pass the force on and transmit the movement to the driven body. The rollers simultaneously roll along the grooves of the two bodies while travelling along a well-defined path, the roller coupling path, in the space between the two bodies. It is important to note that the rollers carry out pure rolling motion in this system without any sliding. As the rollers travel along the roller coupling path they reach the end of the path and exit from coupling. Then they are guided back to the beginning of the path where they enter the roller coupling path again and introduce coupling between the two bodies again. This coupling-recycling-and-coupling-again cycle can be repeated continuously and indefinitely as it is illustrated in the figure below.