I. Check the appearance parts of the watch
The appearance of the watch can be checked from the aspects of Shell, watch cover, dial and minute and second needle. The case should be free of sand holes and obvious scratches, and the edges and corners should be symmetrical; The rotation of the back cover and upper shell should be tight; The distance between the two watch rings and the case should be equal, the hole for installing ear Juan should be in the position of the tail of the watch case foot, and the depth of the hole should be appropriate, so that the watch ring is not easy to fall off; The watch cover should be free of defects and scratches, transparent and bright; The three-pin installation is correct, there should be a correct safety gap between the needle and the needle, watch cover and dial; The dial and pointer coating finish is good, no patch stain, dial scale lines or luminous spots are complete; there is a gap of 0.1-0.3mm between the head and the case.
Second, check the sensitivity of the watch
The sensitivity of the Watch refers to its torsion pendulum automatic swing flexibility. The check method is as follows:
1) gently shake the watch that has not stopped walking on the spring, and observe the second hand moving with the help of the shaking force: If the second hand stops walking in a short time, it means that this watch can walk all after it is fully wound up (that is, the clockwork has no torque), and the sensitivity is high; If the second hand continues to walk for a long time, it means that the watch cannot be finished after it is fully wound up (that is, the spring also stores torque), and the sensitivity is not high or the watch machine is faulty.
2) turn your head slowly and observe the starting situation of the second hand when you stop walking on the watch that has not been put on the spring bar: the less the rotation of the upper handle is, the earlier the second hand starts, the higher the sensitivity of the meter; Otherwise, the sensitivity is low or the meter machine has other faults. However, it should be noted that due to the high rigidity of the hairspring, the fast swing watch needs a little more clockwork than the watch machine with traditional frequency (18000 times/hour). The watch with high sensitivity continues to walk for a long time after it reaches the foot.
3. Check the distance and position of the watch pointer
Watch needles should be kept at a certain distance between watch cover, dial and three needles. Otherwise, collision will affect the normal operation of watch machine. During the inspection, you can dial the needle to observe. Check whether the position and mutual cooperation of the hour hand and the minute hand are normal: dial the minute hand and the hour hand to 3 o'clock and 9 o'clock, and observe whether the two needles are at right angles; Dial to 6 o'clock, whether the two needles are straight; Dial to 12 o'clock and whether the two needles coincide.
4. Check the mechanism on the watch
A normal watch should be easy. When turning the upper strip of the handle head, I first feel looser and tighter gradually. When I can't continue to rotate the head forward, it means that the spring is completely full and the upper body works normally. If a phenomenon such as "Twittering exceptional sound or top teeth slipping occurs when rotating the bar on the handle head, the above mechanism is faulty.
V. Check the watch needle dialing mechanism
The watch should be flexible and reliable when dialing the needle and rotate the pointer evenly. During the inspection, the tightness of friction coordination between the sub-wheel and the center axle should be checked. When the needle is dialed, if there is no feeling of looseness or tightness, it indicates that the friction force of the wheel is normal and the amount of refueling is appropriate. On the contrary, the needle dialing machine is faulty.
