Circular Pallets Deadbeat Escapement

OR: dead-beat escapement An escapement in which the escape wheel does not 'recoil'; it remains stationary and does not recoil between its forward motions. -Dead Beat escapements are so called be-cause except during the actual impulsion, the wheel remains stationary, a point being supported either against the axis of the balance itself, or against the accessory piece, concentric with this axis, which catches it in its movement of rotation. The cylinder and duplex escape-ments in watches and the pin and Graham escapements in clocks are examples of this class.- H.G. Abbott. Abbott's American Watchmaker and Jeweler. Chicago, Hazlitt & Co., 1898 -In escapements of this class the face of the pallet on which the tooth of the escape-wheel drops is concentric with its centre of motion, and hence by the further swing of the balance in the supplementary arc no recoil is effected on the escape-wheel, and the wheel remains at rest, or dead, till, on the return motion of the balance, the impulse plane of the pallet is brought under the point of the tooth, and then the power from the train acts on the escapement.- Paul N. Hasluck. The Watch Jobber's Handybook. A Practical Manual. London, 1889 NOTES: 1. The deadbeat escapement was invented by George Graham (1673-1751) in 1715 and is still in use for regulators and other precision clocks. The deadbeat escapement replaced the less accurate anchor escapement. He also invented the mercurial compensation pendulum. 2. -The deadbeat escapement is an improvement on the anchor [escapement] in that it eliminates the recoil, and remains steady at the end of each beat. It held the field for the most accurate escape for astronomical work for nearly two hundred years. It is still used to-day in high-grade clocks, both long-case and mantel.- Helena Hayward (ed.) The Connoisseur's Handbook of ANTIQUE COLLECTING. Galahad Books, NY, 1960. 320 pp. 3. The cylinder escapement was perfected by George Graham. 4. In horological terms 'dead beat' means to 'move in definite jumps without recoiling'. An example of this is the seconds hand of a dead beat escapement. 5. In the 18th C Pierre Debaufre (1689-1720), a French watchmaker who settled in London as a Protestant refugee, invented a two-wheeled dead-beat escapement known as the Debaufre escapement. 6. -The deadbeat escapement, in use by 1715, was also for pendulum clocks. It evolved from the anchor escapement, but the seconds hand stops dead after each forward motion.- UK Auctioneers website