Balance wheel

Floating Balance Escapement

Alarm Clock Balance Wheel

Chinese movement escapement and jewels

Verge and foliot from De Vick's clock

Giovanni Di Dondi clock

Balance Wheel in Early Watch Berthoud

A balance wheel is a crucial component in mechanical watches and clocks that controls the timekeeping accuracy. It oscillates back and forth, regulating the movement of the gear train and ensuring the consistent advancement of the hands.

History

The balance wheel was first introduced in the 17th century, revolutionizing timekeeping by providing a more accurate and reliable method of regulating the movement of mechanical timepieces. Prior to its invention, timekeeping devices relied on the verge escapement, which was less accurate.

Components

The balance wheel works in conjunction with several other components:

• Hairspring: Also known as the balance spring, it provides the restoring force that causes the balance wheel to oscillate.
• Balance staff: The axle on which the balance wheel is mounted.
• Balance spring: Another term for the hairspring, it is a fine spiral spring that controls the oscillations of the balance wheel.

Function

The balance wheel oscillates at a constant rate, typically several times per second. This oscillation is driven by the mainspring through the escapement, which releases a small amount of energy to the balance wheel with each swing. The regularity of these oscillations is what keeps the timepiece running accurately.

Types

There are several types of balance wheels used in different timepieces:

• Plain balance wheel: A simple wheel without any additional features.
• Compensated balance wheel: Designed to counteract the effects of temperature changes on the timekeeping accuracy.
• Gyromax balance wheel: A modern design that allows for fine adjustments to the balance wheel's inertia.

Maintenance

Proper maintenance of the balance wheel is essential for the accurate functioning of a mechanical watch or clock. This includes regular cleaning, lubrication, and adjustment by a skilled watchmaker.

Related Pages

• Watch
• Clock
• Escapement
• Hairspring
• Mainspring
• Gear train