Lever escapement and other parts out of harder materials than steel, eliminating the need for lubrication. Materials being tried include silicon, nickel phosphorus, diamond, and diamond-on-silicon. Ulysse Nardin in 2001, Patek Philippe in 2005, and Zenith (watchmaker) in 2013 introduced watches with silicon escape wheels. Lever escapement The lever escapement, invented by British clockmaker Thomas Mudge in 1755, is a type of escapement that is used in almost all mechanical watches, as well as small mechanical non-pendulum clocks, alarm clocks, and kitchen timers. An escapement is a mechanical linkage that gives pushes to the timepiece's balance wheel, keeping it rotating back and
Mechanical energy isolated system remains constant in time, as long as the system is free of friction and other non-conservative forces. In any real situation, frictional forces and other non-conservative forces are present, but in many cases their effects on the system are so small that the principle of conservation of mechanical energy can be used as a fair approximation. Though energy cannot be created or destroyed in an isolated system, it can be converted to another form of energy. In a mechanical system like a swinging pendulum subjected to the conservative gravitational force where frictional forces like air drag and friction