Preselector

Preselector

A preselector is a type of gearbox used in automobiles and other machinery. It allows the driver to "pre-select" the next gear before it is actually needed. This type of gearbox was particularly popular in the early to mid-20th century, especially in luxury cars and buses.

History

The preselector gearbox was first developed in the early 20th century. It gained popularity in the 1930s and 1940s, particularly in British and European cars. Notable manufacturers that used preselector gearboxes include Daimler, Alvis, and Lagonda.

Mechanism

The preselector gearbox operates using a combination of clutches and bands to engage the desired gear. The driver uses a small lever or a pedal to select the next gear in advance. When the driver is ready to change gears, they simply press a pedal or move a lever, and the preselected gear is engaged. This system allows for smoother and quicker gear changes compared to traditional manual transmissions.

Advantages

One of the main advantages of the preselector gearbox is the ease of use. It requires less effort from the driver to change gears, making it particularly useful in heavy traffic or for drivers who may have difficulty with a traditional manual gearbox. Additionally, the preselector gearbox can provide smoother gear changes, which can enhance the driving experience.

Applications

Preselector gearboxes were commonly used in luxury cars, buses, and some military vehicles. They were particularly favored in vehicles where smooth and effortless gear changes were important. Although they have largely been replaced by modern automatic transmissions and semi-automatic transmissions, preselector gearboxes are still of interest to vintage car enthusiasts and collectors.

Notable Models

Some notable car models that featured preselector gearboxes include:

• Daimler Double-Six
• Alvis Speed 20
• Lagonda V12

Decline and Legacy

The use of preselector gearboxes declined with the advent of more advanced automatic and semi-automatic transmissions. However, they remain an important part of automotive history and are still appreciated by enthusiasts for their unique mechanism and driving experience.

See Also

• Manual transmission
• Automatic transmission
• Semi-automatic transmission
• Clutch
• Gearbox