Fireplace Bellows
Most people associate a bellows with a leather bag kept by the fireplace, used in the past to make a fire burn more fiercely. A pleated bag is fixed between handles that can be pulled apart and pushed together, forcing the air through inlet and outlet vents that are fitted with valves so the air must enter one end and exit the other. This is its most basic and familiar form. A more robust version is used in iron-making, where it provides oxygen to keep the furnace fire burning.
Using Bellows
The bellows provides the force necessary for a wide range of everyday tools and instruments. A few examples include:
- Cameras: The bellows device functions as a camera zoom, fitting between the lens and the camera body and enabling it to focus on a close subject to achieve larger-than-life sized images on film. It is also used in enlargers. Like the camera, it allows the lens to move toward or away from the film for greater magnification.
- Aerophone Instruments: Bellows were put to use in powering hand-held free reed aerophone instruments (also called “squeezeboxes”) such as the accordion. The accordion is played by compressing and expanding the bellows, which drives air across reeds inside. A keyboard controls which reeds receive airflow, thereby controlling the tones produced.
- Medicine: Bellows have also been put to a variety of medical uses, including raising and lowering hospital beds and dental chairs, and in the past, helping sick patients to breathe.
The use of bellows technology is extensive – especially in machines and automated devices. The bellows is utilized in energy storing devices to build pressure; it is the expanding and contracting force in pistons and provides suspension for bikes and vehicles; it is used in piping systems to compensate for temperature changes; used to gauge pressure changes in machinery; it can be used as a thermostat as it expands or contracts in changing temperatures.
