Stephen Hales, called the creator of pneumatic chemistry, created the pneumatic trough in 1727. This instrument was widely used by many chemists to explore the properties of different airs, such as what was called inflammable air (what is modernly called hydrogen). Lavoisier used this in addition to his gasometer to collect gases and analyze them, aiding him in creating his list of simple substances. The pneumatic trough, while integral throughout the eighteenth century, was modified several times to collect gases more efficiently or just to collect more gas. For example, Cavendish noted that the amount of fixed air that was given off by a reaction was not entirely present above the water; this meant that fixed water was absorbing some of this air, and could not be used quantitatively to collect that particular air. So, he replaced the water in the trough with mercury instead, in which most airs were not soluble. By doing so, he could not only collect all airs given off by a reaction, but he could also determine the solubility of airs in water, beginning a new area of research for pneumatic chemists. While this was the major adaptation of the trough in the eighteenth century, several minor changes were made before and after this substitution of mercury for water, such as adding a shelf to rest the head on while gas collection occurred. This shelf would also allow for less conventional heads to be used, such as Brownrigg's animal bladder.
In general, based on the application, a pneumatic cylinder is usually a single acting cylinder, where there is a single port in the cylinder and where cylinder extension is done by compressed air and retraction by means of open coiled spring. In double acting cylinders two ports both extend and retract by means of compressed air.
Pneumatic tools come in many shapes and form, including small and large-sized hand tools.
The most common types of pneumatic tools include:
The low projectile speed requirement of a toy weapon greatly reduces the amount of air pressure needed; combined with the importance of safety in the toy industry, this has led to widespread adoption of pneumatic firing mechanisms in toy weapons, where a propellant reaction is not appropriate (although other technologies, such as rubber bands, can be used).
The toy industry has produced a number of pneumatic toy weapons, which fire small, lightweight (often plastic and frequently hollow) projectiles at relatively low speeds. Airsoft and paintball guns are a popular toy that operates this way; when used with adequate safety equipment (eye protection at a minimum) these may be used in games involving shooting at other players.
Pneumatic valve springs gave Renault an advantage with its turbocharged engines, often said to be one of the most powerful. However, reliability and poor handling of their chassis kept the cars from success until 1989, when Renault provided Williams with a new V10 engine that began a winning streak.
Pneumatic valve springs are also found in several Moto GP motorcycle engines, debuting in 2002 with the Aprilia RS Cube. In 2005, Team Roberts was the first to use pneumatic valves full-time in their uncompetitive KTM powered bike. Today, almost all of the MotoGP teams use pneumatic valve technology on their bikes, including Yamaha, Suzuki and Honda. Ducati uses a desmodromic design.
Additionally, some users of pneumatic jackhammers may use a pneumatic lubricator which is placed in series with the air hose powering the air hammer. This increases the life and performance of the jackhammer. Specific lubricant is filled in the pneumatic lubricator. Furthermore, air compressors typically incorporate moisture into the compressed air leading to freeze-ups of the jackhammer or air hammer in cold weather.
Since large trucks typically use air brakes, the system does double duty, supplying compressed air to the brake system. Pneumatic starters have the advantages of delivering high torque, mechanical simplicity and reliability. They eliminate the need for oversized, heavy storage batteries in prime mover electrical systems.
Pneumatic core drilling machines are used where there is a danger of explosion or fire due to electrical sparking. The motor is driven by compressed air and the magnet is a permanent magnet instead of an electromagnet.
On larger diesel generators found in large shore installations and especially on ships, a pneumatic starting gear is used. The air motor is normally powered by compressed air at pressures of 10–30 bar. The air motor is made up of a center drum about the size of a soup can with four or more slots cut into it to allow for the vanes to be placed radially on the drum to form chambers around the drum. The drum is offset inside a round casing so that the inlet air for starting is admitted at the area where the drum and vanes form a small chamber compared to the others. The compressed air can only expand by rotating the drum, which allows the small chamber to become larger and puts another one of the cambers in the air inlet. The air motor spins much too fast to be used directly on the flywheel of the engine; instead a large gearing reduction, such as a planetary gear, is used to lower the output speed. A Bendix gear is used to engage the flywheel.
Air (or other gas) pressure is the power source for pneumatic valve actuators. They are used on linear or quarter-turn valves. Air pressure acts on a piston or bellows diaphragm creating linear force on a valve stem. Alternatively, a quarter-turn vane-type actuator produces torque to provide rotary motion to operate a quarter-turn valve. A pneumatic actuator may be arranged to be spring-closed or spring-opened, with air pressure overcoming the spring to provide movement. A "double acting" actuator use air applied to different inlets to move the valve in the opening or closing direction. A central compressed air system can provide the clean, dry, compressed air needed for pneumatic actuators. In some types, for example, regulators for compressed gas, the supply pressure is provided from the process gas stream and waste gas either vented to air or dumped into lower-pressure process piping.
In Germany and some other European countries, the pneumatic two-tone (hi-lo) siren consists of two sets of air horns, one high pitched and the other low pitched. An air compressor blows the air into one set of horns, and then it automatically switches to the other set. As this back and forth switching occurs, the sound changes tones. Its sound power varies, but could get as high as approximately 125 dB, depending on the compressor and the horns. Comparing with the mechanical sirens, it uses much less electricity but needs more maintenance.
A pneumatic jackhammer, also known as a ' or ', is a jackhammer that uses compressed air as the power source. The air supply usually comes from a portable air compressor driven by a diesel engine. Reciprocating compressors were formerly used. The unit comprised a reciprocating compressor driven, through a centrifugal clutch, by a diesel engine. The engine's governor provided only two speeds:
Pneumatic level sensors are used where hazardous conditions exist, where there is no electric power or its use is restricted, or in applications involving heavy sludge or slurry. As the compression of a column of air against a diaphragm is used to actuate a switch, no process liquid contacts the sensor's moving parts. These sensors are suitable for use with highly viscous liquids such as grease, as well as water-based and corrosive liquids. This has the additional benefit of being a relatively low cost technique for point level monitoring. A variation of this technique is the "bubbler", which compresses air into a tube to the bottom of the tank, until the pressure increase halts as the air pressure gets high enough to expel air bubbles from the bottom of the tube, overcoming the pressure there. The measurement of the stabilized air pressure indicates the pressure at the bottom of the tank, and, hence, the mass of fluid above.
Pneumatic airguns propel the projectiles by utilizing the pneumatic potential energy within compressed air, which is pressurized beforehand and stored inside the gun, and then released through valves during shooting. Single-stroke and multi-stroke pump guns utilize an on-board hand pump to pressurize air in an internal reservoir, while pre-charged pneumatic guns' reservoirs are filled from an external source using either a high-pressure stand pump or by decanting air from a larger diving cylinder.
Pneumatic (compressed air) systems are rarely found in passenger cars. Larger vehicles often use air brakes and the pressure may be used to drive other systems. Windshield wipers, automatic gear boxes, and other common hydraulic or vacuum powered accessories are often adapted. On buses where the engine is often at the rear of the vehicle, compressed air may be used for the throttle and clutch.
Some gas turbine engines and diesel engines, particularly on trucks, use a pneumatic self-starter. In ground vehicles the system consists of a geared turbine, an air compressor and a pressure tank. Compressed air released from the tank is used to spin the turbine, and through a set of reduction gears, engages the ring gear on the flywheel, much like an electric starter. The engine, once running, drives the compressor to recharge the tank.
The pneumatic siren, which is a free aerophone, consists of a rotating disk with holes in it (called a chopper, siren disk or rotor), such that the material between the holes interrupts a flow of air from fixed holes on the outside of the unit (called a stator). As the holes in the rotating disk alternately prevent and allow air to flow it results in alternating compressed and rarefied air pressure, i.e. sound. Such sirens can consume large amounts of energy. To reduce the energy consumption without losing sound volume, some designs of pneumatic sirens are boosted by forcing compressed air from a tank that can be refilled by a low powered compressor through the siren disk.