① Pendulum: composed of a pendulum, a pendulum rod, a hanging pendulum device, and a period adjustment device. Used in fixed clocks. When the pendulum deviates from the plumb line (equilibrium position) at any angle under external force and is released, under the action of gravity, the pendulum will move back and forth around the fulcrum. The vibration process is the process of alternating the kinetic energy and potential energy of a pendulum.

② Twisting pendulum: mainly composed of a pendulum plate and suspension wire. The lower end of the suspension wire is fixed on the swing plate, and the upper end is fixed on a fixed fulcrum. The cross-section of the suspension wire can be rectangular or circular. The torsion pendulum often forms an escapement speed control system with a backward escapement mechanism or a fork shoe escapement mechanism. Twisted pendulum has a long vibration period (several seconds to tens of seconds), and is mostly used for fixed clocks that save energy and have a longer duration of travel.

③ Cycloidal hairspring vibration system: The inner and outer ends of the hairspring are respectively fixed on the pendulum shaft and swing clamp plate. When the pendulum wheel deviates from its equilibrium position due to external force and begins to swing, the hairspring is twisted to generate potential energy, commonly known as restoring torque. This torque causes the pendulum to move towards its equilibrium position.

The upper needle is a mechanism that tightens the spring in the primary system and adjusts the clock and minute hands to correct the time indicated by the clock. When loading, the vertical wheel and clutch wheel are in a meshing state. When shifting the needle, the clutch wheel and vertical wheel disengage and engage with the shifting needle wheel.