Pallet fork

The pallet fork is the pivoted part that sits between the escape wheel and the balance. It carries two pallets that take the escape wheel's teeth in turn, holding the wheel still and then letting it move on one step, and it passes that step to the balance through a pin. Its names vary with the writer: the Seiko Museum Ginza describes the escape wheel's teeth pushing "against the pallet stones of the anchor", while the published European patent application EP 3 185 083 A1, Mechanical timepiece mechanism with anchor escapement, filed on 23 December 2015, speaks of "a pallet-lever 4 arranged to move alternately into abutment with two banking elements 24, 25," the fixed stops that limit its travel at each end of its swing.

The pallets themselves are normally jewels. The same museum, describing the cheaper pin-lever escapement, says metal pins were used "in place of the rubies that were used in the club tooth escapement to reduce wear on the anchor pallets and impulse pin": in the ordinary lever escapement the working faces are set stones, not steel.

No standards body defines the part. The Federation of the Swiss Watch Industry's published list of available NIHS norms for the Swiss watch industry contains no norm titled for the anchor, the pallet lever or the escape wheel, and ISO's horological vocabulary is paywalled. What is quoted above is therefore a museum record and a patent application: a primary record of how the part is described, not a normative definition.