1、 Composition and function of quartz clock movement

Although there are many types of quartz clocks, whether they are seated, hanging, or have alarm or non alarm functions, their internal movement structures are similar.

1. Quartz crystal oscillator: Its function is equivalent to the balance spring of a mechanical clock, which generates stable frequency oscillation signals in the circuit and is a key component to ensure timekeeping accuracy. Generally speaking, the higher the frequency of the crystal oscillator, the higher the accuracy of the divided second pulse and the more accurate the travel time.

At present, there are two types of quartz clock crystal oscillators popular in the market: one is the low-frequency type, with an oscillation frequency of 32.768kHz; The other type is high-frequency type, with an oscillation frequency of 4.1943MHz. To reduce external influences and enhance seismic and impact resistance, the oscillator is sealed in a cylindrical metal or glass shell during manufacturing, leaving only the pins.

2. Adjusting capacitance: Its function is similar to the fast and slow calibration needle of a mechanical clock. It is designed to eliminate the error of the resonant frequency of a quartz crystal oscillator itself and the influence of distributed capacitance on the oscillation frequency. An external capacitor is used to correct the oscillation frequency to meet the accuracy of travel time.

When the quartz clock travels too fast, the capacitance can be increased, and conversely, the capacitance can be reduced.

3. Stepper motor: Its function is to convert electrical energy into mechanical energy, and the iron cores of the motor stator coils are made of high permeability Permalloy material. The DC resistance of the coil varies depending on the product, generally ranging from 350 to 500 Ω.

4. Integrated circuit: Together with peripheral components, it generates accurate reference frequencies and outputs stable driving signals and alarm signals.

Integrated circuits are generally CMOS devices, which have the characteristics of low operating voltage, low power consumption, strong anti-interference ability, and long lifespan. It contains internal components such as oscillation, frequency division, narrow pulse formation, driving, and control. Like crystal oscillators, they are also divided into two categories: high-frequency and low-frequency applications.

5. Alarm device: It is a device that converts alarm signals or time signals into sound. Under the control of integrated circuits, the sound signal is generated by the circuit output and amplified to drive the buzzer or speaker to produce sound.

6. Work process description: After connecting the power supply, the integrated circuit and its peripheral quartz crystal oscillator, adjusting capacitors, etc. generate standard 4194304Hz or 32768Hz oscillation signals. After being processed by the internal frequency division circuit and narrow pulse forming circuit of the integrated circuit, the pulse signal is applied to the stepper motor through the driving circuit. Under the second pulse driving, the magnetic field generated by the stator coil of the stepper motor changes with the alternating changes of the pulses. The rotor rotates at a step angle of 180 ° per second, and then drives the transmission gear to operate the entire mechanical wheel system and pointer, displaying time. After setting the alarm function, when the operation reaches the set time, the integrated circuit outputs an audio signal to the alarm device, emitting an alarm signal.