Pin-pallet escapement revealed in a cutout on the clock's face. 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
Grasshopper escapement in the stable block at Brocklesby Park in Lincolnshire. This proved to be unreliable, needing repeated attention by which Harrison was inconvenienced, so around 1722 he modified the escapement by putting a hinge in the middle of each arm of the anchor. The hinged pallets both pointed the same way, opposing the rotation of the escape wheel. As the escape wheel pushes the pallet, the hinge moves away from the escape wheel. The pallet pivots about its contact point with the wheel as it pushes the anchor. At the same time, the other pallet is approaching the wheel. When it