Pin-pallet escapement Pin-pallet escapement A Roskopf, pin-lever, or pin-pallet escapement is an inexpensive, less accurate version of the lever escapement, used in mechanical alarm clocks, kitchen timers, mantel clocks and, until the 1970s, cheap watches now known as pin lever watches. It was patented by German watchmaker Georges Frederic Roskopf in 1867, suggested to Roskopf by Jules Grossmann. An escapement is the mechanism in a mechanical timepiece that gives the balance wheel pushes to keep it moving back and forth, and releases the timepiece's gears to advance a fixed amount with each swing of the wheel, thus moving the hands forward at
Anchor escapement is still a frictional rest escapement because the sliding of the escape tooth on the dead face adds friction to the pendulum's swing, but it has less friction than the recoil escapement because there is no recoil force. In contrast to the backward slant of the anchor escape wheel teeth, the deadbeat escape wheel teeth are radial or slant forward to ensure that the tooth makes contact with the 'dead' face of the pallet, preventing recoil. In 1826 British astronomer George Airy proved that a pendulum that is driven by a drive impulse that is symmetrical about its bottom equilibrium