To allow the construction of hybrid systems, where the 4-20 mA is generated by the controller, but allows the use of pneumatic valves, a range of current to pressure ( I to P ) converters are available from manufacturers.
32.
This despite the pneumatic valves Cavaille-Coll installed to help pull the miles of wires and pieces of wood that connect the keys at the console to the pipes that actually produce the sound, some of them 50 feet away.
33.
These file stores, a high maintenance item with pneumatic valves and other mechanical parts, were replaced in the 1980s with the 1A Attached Processor System ( 1AAPS ) using the 3B20D Computer to provide access to the " 1A File Store ".
34.
After the 1985 season the Renault works team ended participation in Formula One, but continued as an engine supplier for Tyrrell and Lotus . 1986 saw the introduction of the EF15B engine, which included several innovations, like static ignition and pneumatic valve return.
35.
Other mechanisms can be used in place of valve springs to keep the valves closed : Formula 1 engines employ pneumatic valve springs in which pneumatic pressure closes the valves, while motorcycle manufacturer Ducati uses desmodromic valve drive which mechanically close the valves.
36.
The " cast " of the musical revue uses tones recorded on tape to vibrate a metal reed that closes a circuit to trigger a relay, which sends a pulse of electricity to a mechanism that causes a pneumatic valve to move part of the figure.
37.
They were replaced by pneumatic valve springs introduced by Renault, which inherently have a rising rate ( progressive rate ) that allowed them to have extremely high spring rate at larger valve strokes without much increasing the driving power requirements at smaller strokes, thus lowering the overall power loss.
38.
The machine generates forces up to 300 times the force of gravity ( 300 G's ) and operates by using a smooth-walled, rotating bowl to stratify the material into heavier and lighter fractions then uses pneumatic valves to control the amount of heavy material that reports to the concentrate collection stream.
39.
In addition to the use of pneumatic valve springs a Formula One engine's high RPM output has been made possible due to advances in metallurgy and design allowing lighter pistons and connecting rods to withstand the accelerations necessary to attain such high speeds, also by narrowing the connecting rod ends allowing for narrower main bearings.
