Continuously-Variable Transmissions in Vehicles With Particular Attention to Efficiency Control Through Unstepped V-Belt Control 785053

The continuously-variable transmission is especially promising if it can maintain engine operation at optimal fuel consumption levels. The most widely-used V-belt regulators cannot yet fulfill this demand. After description of transmission types, efficiency losses, and influencing factors, the paper discusses selected examples of efficiency analyses of wide V-belts. Evaluation of these analyses leads to the following recommendation:

For the Belt Manufacturer:

- Wide V-belts must incorporate low flexural rigidity, high transverse rigidity, and low hysteresis values.

- The specified characteristics must be maintained under all operational conditions.

- Geometric and physical specifications must be upheld.

For the Transmission Manufacturer:

- The optimal angular difference must be maintained.

- Belt tension optimal for fuel economy at each level of engine loading must be assured.

- The belt should only be wide enough to guarantee the required changes in transmission-ratios.

- The belt should only be large enough as is necessary for power transmission.