pullchain

A pull chain, also known as a pull cord or pull string, is a simple mechanical device used to activate or deactivate a switch. It typically consists of a cord or chain attached to a lever or button that, when pulled, completes or breaks an electrical circuit. This mechanism is commonly found in household fixtures such as ceiling fans, light fixtures, and some types of blinds.

The primary function of a pull chain is to provide a manual and accessible way to control a device. In the case of a ceiling fan, pulling the chain might cycle through different speed settings or turn the fan on and off. For a light fixture, a pull chain usually serves as a simple on/off switch, especially in situations where a wall switch is inconvenient or absent. The length of the chain is often designed to be easily reachable from a standing position.

The internal mechanism of a pull chain switch is relatively straightforward. It usually involves a series of contacts that are either brought together or separated by the movement of the pull cord. For multi-speed fans, the chain might engage different sets of resistors or electrical pathways to alter the motor's speed. Due to their simplicity and low cost, pull chains remain a popular choice for certain applications, offering a reliable and straightforward method of device control.