locking face in a sentence

• The pallets in a traditional lever escapement have two angled faces, the locking face and the impulse face, which engage the escape wheel teeth.
• During the extremities of the pendulum's swing, the escape wheel tooth rests against this locking face, providing no impulse to the pendulum, which prevents recoil.
• Near the bottom of the pendulum's swing the tooth slides off the locking face onto the angled " impulse " face, giving the pendulum a push, before the pallet releases the tooth.
• Once the entrance tooth leaves the impulse plane of the entrance pallet, the wheel is able to turn a small amount ( called the drop ) until the exit tooth of the escape wheel lands on the locking face of the exit pallet.
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