Compressed Air Engine

A compressed air engine is an engine which works by expanding compressed air. Another name for a compressed air engine is a pneumatic motor. They convert compressed air to mechanical work using either linear or rotary motion. The linear motion is generally a piston while rotary is a vane type air motor. Compressed air engines have existed for around 200 years and have ranged in size from handheld engines to engines with several hundred horsepower. Performance can be improved by heating the intake air or heating the actual engine. Using a compressed air engine tool is very widespread in the handheld tool industry

Compressed Air Engine: How They Work

A compressed air engine using the linear motion works in this fashion. Compressed air is put in an airtight chamber where the shaft of the piston is. In this chamber is a coiled spring that keeps the chamber completely open when air is not pumping. Air is fed into the airtight shaft section. As the air increases the pressure in the piston, it begins to move. At its maximum length air pressure is released and the spring closes off the chamber to return to where the cycle began.

The rotary type of compressed air engine produces rotational motion to a shaft. What rotates is a slotted rotor that is on a drive shaft. The slot is filled with a rectangular vane which extends to the wall of the housing. Air is pumped through an input which pushes the vanes into a rotational flow around a central shaft. Rotational speeds can go up to 25,000 RPM. This type of compressed air engine is used to start industrial engines powered by diesel or natural gas.

Compressed Air Engine: Where They Are Currently Used

Compressed air engine tools are extensively used in air impact wrenches, drills, sanders cutters, grinders and the like. The compressed air powers the compressed air engine so that humans do not have to work as hard. Many people have attempted to apply the compressed air engine technology to transportation such as automobiles. There are several people working on this technology. Cars would initially have limited distance and would have to compress the air around them in order to refuel (takes hours) unless compressed air refueling stations become widespread. The advantage of an air car is that there is no pollution put out at the tailpipe and another advantage cited for compressed air engine cars is that it will only cost two dollars electricity to fill the car up and they will get around 100 miles to the gallon (equivalency, since air doesn’t come in gallons) Tata Motor Company of India has plans to introduce an automobile powered by a compressed air engine in either 2011 or 2012. Another company in Melbourne Australia is working on compressed air motor technology that would enable the car to be powered by renewable energy effectively. All the compressed air engine cars are lightweight and made of aluminum to increase their range.

Air compressors also run most of the nail guns used in the construction industry from framing nailers to nailers used for putting up trim in houses and of course impact nailers used in roofing.

Compressed air engine technology has many possible future potential uses other than its current application which is widespread use in some of the handheld tools mentioned in the previous paragraph. It’s great that cool things are coming with this technology.