If the person has been to the ubiquitous tyre shop or watched the slick Formula Teams changing tyres in double quick time during the TV , you could have seen the air hammer tools with their staccato hammering action, active. The tools are driven by compressed air and possibly at their heart are piston air motors. Wikipedia defines the piston air motor (sometimes also called an air drive, or compressed air engine) as the machine that is powered by compressed air and it converts reciprocating motion into rotary initiative.
How they work usually compressed air is fed continuously in the top cylinder this kind of pushes down a spring-loaded piston until the top in the piston passes the exhaust port(s) and also the cylinder then goes duplicate and the two-stroke cycle begins spine. This is the hammering noise that you hear on the tyre work shop. For most applications, the piston air motor comprises between two and six cylinders to smooth out the power generated by overlapping the electricity pulses. The reciprocating action is transformed into rotary motion in an identical fashion together with normal combustion engine. This type is called the radial type and it's the simplest type with the least moving components. They are commercially available in sizes from fractions of something like a kilowatt to about 25 kW at 4,500 rpm
Alternatively, the axial type arranges supply around the shaft and also the power is transmitted inside the piston con rods using spur gears. This arrangement is often used where poor axial profile is required say as the hand-held power drill. The efficiencies of the two sorts are similar but more than axial type requiring more maintenance on high torque-applications. They do also produce slightly less torque than the equivalent axial type.
The piston air motor has an assortment of characteristics that make it ideal where an electric motor would halt an option. The air motor doesn't spark and therefore it is treated in potentially explosive atmospheres as from petro-chemical installations, automotive workshops, mines and fume laden paint spray booths. They could be especially more compact with a reduced axial cross-section than very same electric train's motor. They can be run at low speeds (by throttling the compressed air supply) and retain their high efficiency; typically 70%.
The air piston motor drive develops its maximum torque at start up or when stalled naturally characteristic helps eminently suitable for the air spanners played with the tyre shop. In case you have ever for you to take off a wheel nut bash car has been in the type shop, you can attest to the difficulty of undoing the wheel nut by the car spanner. This high torque at zero rpm would damage an electric motor or cause power circuit trips to function without some protective clutch arrangement.
Another benefit of the air motor during the electric motor is that adiabatic growth of the compressed air causes it to cool thus takes heat from motor. Which entirely opposite to electrical motor where waste energy is converted to heat and thus electric motors need specific cooling measures like internal axial fans, spur gears and over-temperature cut-off devices. Piston air motors have short-stoke piston action and low-weight parts; thus making then have a low-interia. This characteristic makes all the piston air motor start and stop very quickly and being a result, uses of a stepper motor are simple, effective and accurate in stance. The electronic control of compressed air pulses makes this an ideal industrial machine tool iphone app.
These days, the smaller piston air motors are produced in robust plastics and stainless steel such to be the Huco Dynatork motors, which run on oil-free compressed air and these have opened the applications to clean environments regarding example found in food production and medical applications.