Working principle of quartz watch
Just like a tuning fork vibrates according to a certain law, when the crystal is affected by the battery power, it will also vibrate regularly.
The crystal vibrates as high as 32,768 times per second. We can design a simple circuit to calculate its vibration times. When it counts to 32,768 times, the circuit will send a message to let the second hand go forward for one second.
Because the timely vibration is quite regular, the error rate of a day will not exceed 1 second even for a cheap quartz watch.
Quartz watches can also be called "timely vibrating electronic watches" because it uses timely "vibration phenomenon".
When subjected to an externally applied voltage, it will deform and expand. On the contrary, if it is compressed in time, it will generate electricity at both ends of the time. This property can also be seen in many crystals, which is the so-called "piezoelectric effect".
Quartz watch is a crystal that vibrates periodically and continuously, which brings us accurate time.
First of all, when the quartz watch is energized, it will vibrate correctly at a frequency of 32,768 Hz. Then, this frequency must be converted into a signal current period of 1Hz*** current that changes once every second.
Increase the amplitude of some signals * * * because the current generated by vibration is very weak * * *, and then start the rotor gear with some signal current, and the second hand on the watch will start accordingly.
After that, the minute hand and the hour hand are all related to the principle of mechanical structure. For example, if the second hand jumps 60 times, the minute hand will jump.
All quartz watches are equipped with batteries. It provides energy for integrated circuits and quartz resonators, and vibrates 32,768 times per second. There is something faster than this. The integrated circuit is the "brain" of the watch. It controls the vibration of the quartz resonator and acts as a frequency divider. 32,768 vibrations divided by 65,438+05 vibrations produce a pulse per second. With a second of "raw material", you can drive the clock.
With the application of timely crystal, watches can be mass-produced, not only the production speed is much faster than before, but also the price has dropped. The world can produce about 500 million watches every year.
Element structure of quartz watch
CMOS integrated circuit
The full name of the integrated circuit of quartz watch is CMOS. It controls all the functions of the electronic watch. The area of the integrated circuit chip is about 65438 00 square millimeters. Spot weld the lead quartz watch connected to the circuit board with gold wire or aluminum wire, and then protect it with black sealant. This kind of integrated circuit is characterized by high integration, that is, a small silicon wafer can accommodate thousands of transistors at the beginning, and the power consumption is extremely low. According to the record of semiconductor quality in the past, under the condition of reasonable use, the probability of integrated circuit damage is very small and its life should be very long. Common electronic watch integrated circuit damage, most of them are caused by external water vapor, static electricity and other * * * damage.
liquid-crystal display
It is generally believed that there are only three states of matter: solid, liquid and gas. This view is not completely correct, especially for some organic substances, changing from solid to liquid is not a simple transformation, but a rather complicated transformation process. For example, organic matter melts at 16℃ and becomes a completely clear liquid at 76℃. At this time, on the one hand, it has the fluidity of liquid, and at the same time it has the properties of liquid crystal, that is, the optical and electrical characteristics of crystal, so it is an intermediate state between solid and liquid, so it is called liquid crystal. Liquid crystals are generally composed of camphor-like cylindrical symmetric molecules.
Synchronous oscillator
It is a kind of silicon oxide crystal, which can be divided into artificial crystal and natural crystal. Because rock crystal contains impurities, artificial crystals are generally used in electronic watches. Timely has such characteristics; When electricity is applied to the crystal, the crystal is mechanically deformed, and when pressure is applied to the crystal, the crystal is deformed to generate electric energy. This phenomenon is called synchronous piezoelectric effect. Because of this characteristic, it has a high and stable oscillation frequency, so it is considered as an ideal oscillation device for electronic watches. Because the balance wheel is replaced by the crystal oscillator, the travel time accuracy of the electronic watch is 1000 times higher than that of the mechanical watch.
joist
The fine-tuning capacitor and the timing oscillator constitute the oscillating circuit of the electronic watch. Adjusting the capacity of this capacitor can change the oscillation frequency and reach the standard 32768Hz. The smaller the capacity, the higher the frequency, whether it is a trimming capacitor or an oscillating capacitor. Description, suppose that at the beginning, the metal parts of the rotor and stator are just aligned, that is, 0. At this time, the maximum capacitance is * * * 3 5pf * *, and the frequency is the lowest. When the relative angle changes to a certain point, the frequency is exactly 32,768 h, and then it reaches the minimum capacitance of 5PF, at which time the frequency is also the highest, so that the loop change may not be like an ideal curve in actual adjustment, but as long as there is an adjustment point of 32,768 h, the purpose of adjustment can be achieved.
Oscillating capacitance
The boosting, stabilizing and oscillating capacitors are small ceramic capacitors, and the ceramic medium and the Ag-Pd electrode layer are superimposed to form a capacitor. Swiss watches are used for boosting and stabilizing capacitors. Depending on CMOS, their values are 0.2uf, 0.0 147uf or 0. 1uf. Oscillating capacitance, also known as compensation capacitance, has different values due to different oscillator load capacitances. Oscillator with load capacitance CL of 10.5PF; The oscillation capacitance is 18PF, CL is 12.5PFe, and the oscillation capacitance is 27PF. Some CMOS chips already have internal oscillation capacitors, so as long as the appropriate oscillator is selected, there is no need for external oscillation capacitors.
Matters needing attention of quartz watch
1, the calendar, day of the week and month phase of the watch should not be adjusted between 2 1: 00pm-3: 00am. At this time, the calendar function is running, and it is also the time when the gear teeth are not clenched. Frequent movements will damage the internal parts of the watch.
2. There are two types of calendar jumps in a week, fast and slow, because the formats are different. The 1 calendar jump is completed within 5 minutes, and the second calendar jump is completed within 3 hours.
If you think the watch with spiral crown is suitable, don't pull it hard. First, turn the locked crown counterclockwise. After debugging, turn the crown clockwise and push it into the lock to avoid water ingress.
4. If you need to use the calendar to adjust the date of the watch, please adjust the calendar to the day before you need it, and then turn the hour hand to adjust the date. The date will change when the pointer passes 12 midnight, which can prevent the confusion between day and night caused by directly adjusting the date.
5. If the function of the watch is complicated, please read the attached text carefully first.
Types of quartz watches
Quartz watches can be divided into digital quartz electronic watches, pointer quartz watches, automatic quartz watches and optical kinetic energy watches.
Digital quartz electronic watch
The function of the wristwatch, which combines the piezoelectric effect of the timekeeping crystal and the bipolar tube liquid crystal display, is completely completed by electronic components.
Indicating quartz watch
The energy of quartz watch comes from silver oxide button cell. After the silver button cell oxide provides a specific voltage to the integrated circuit, the oscillator vibrates through the oscillator circuit and the quartz resonator in it, forming an oscillator circuit source. An alternating bidirectional pulse signal is formed to drive the stepping motor to rotate intermittently! Further drive the transmission gear train, so that the watch hand can accurately display the time.
Automatic quartz watch
Combine that advantages of automatic mechanical watch and quartz watch. It does not need batteries, and the wearer can choose to wind it manually or charge it automatically. Its working principle is to use the dancing of the arm to drive the pendulum in the watch to rotate and generate energy to push the internal micro-motor to convert it into energy, so as to provide sufficient power for the timing device in the watch, and the excess power will be stored by the micro-capacitor for later use.
Optical kinetic energy watch
Solar chips convert light energy into electric energy, which is stored in recyclable titanium-lithium-ion rechargeable batteries. The electric energy generated by the battery generates a pulse signal to the coil through the integrated circuit, which generates a magnetic force to drive the stepping motor, which drives the gear to rotate and the indicator to indicate the time. After fully charged, it can run in the dark for about 40- 180 days, with accurate travel time, and the life of rechargeable battery can reach 10 years. Matters needing attention of quartz watch