In the verification process of the pressure gauge, the phenomenon of tapping the movement of the watch case often occurs, mainly because the balance spring is not enough to be tight, the tension is large or the ends of the balance spring are not tightly fastened. Therefore, it is extremely important to install and disassemble the balance spring of the pressure gauge. So, how to install, disassemble and adjust the hairspring of the pressure gauge? First of all, we must know the role, characteristics and technical requirements of the hairspring.
1. The role of hairspring
The reaction torque is generated by the balance spring, so that the gear maintains the one-way tooth profile in close contact, thereby eliminating the unstable state of the indication caused by the gap between the center gear and the sector tooth, the gap between the transmission shaft and the connecting rod, and the pointer is installed stably. , tap the case to show the same value. That is, when the pressure is removed, the pointer is returned to the zero position, and the nail is stopped immediately.
2. Characteristics of the hairspring
When the pressure gauge measures the lower limit of the tension, it is at the maximum torque state. As the pressure increases, the torque gradually decreases, and the reverse loaded hairspring is reversed. At the zero position, the hairspring is in a pre-tightened state, and as the pressure increases, the hairspring gradually relaxes. When the hairspring is too long, the rigidity is weak, the elasticity is poor, the pointer is unstable, and even the free state is presented in a circle. When the hairspring is too short, the frame distance of the Zhang Da is very large, and even the one side is circled, and the force is not uniform. The silk is boiled.
3. Technical requirements for hairspring
(1) There should be no significant eccentricity after installation, and the plane is perpendicular to the mandrel.
(2) After slack, tightening or opening, the circle should be clear, the circle spacing is relatively uniform, and there is no frame-closing phenomenon.
(3) The core hole, diameter and torque should meet the installation specifications.
(4) After installation, the ends of the hairspring are fastened without looseness.
4. Installation and disassembly of the pressure gauge spring
There are two kinds of directions, which are installed in the direction of the big hairspring. The force of the hairspring is large, and the pointer is close to the dial to limit the nail. Installed in the direction of the shrinking hairspring, the balance of the hairspring is smooth (as shown in Figure 2). In addition, pay attention to the following points during installation and disassembly:
(1) Before loading the hairspring, first check the fit of the hairspring ring to the shaft. The hairspring ring is loose and clamped with a vise; the hairspring ring is tight, and the punch is enlarged, and the hole is slightly smaller than the shaft. Then, the hairspring is inserted into the central axis, and the other end of the central shaft is placed in the eye of the iron pier, and the hairspring ring is hollowed out to be nailed to the top surface of the center gear. After the nail is generally fastened, no need to clamp again.
(2) Check if the hairspring ring is loose on the pointer shaft, clamp the hairspring ring with a vise, and test the hand shaft. If it is installed on the movement, hold the pointer shaft by hand and swing the fan-shaped teeth for observation. The hairspring ring must not rotate.
(3) Before inserting the tail end of the hairspring into the pin hole, hold the outer ring with your hand to stop the hairspring from shaking for easy operation. After the tail end of the hairspring is inserted into the pin hole, puncture the tip of the forceps into the pin hole to facilitate the smooth insertion of the hairspring pin. After the hairspring pin is placed in the pin hole, push the flat end of the tweezers with the tweezers, and then use the tiger. The pliers clamp the balance spring pin into the pin hole. Both ends of the hairspring must be pinned tightly. If loose, the indication value is unstable. Check if the outer end of the hairspring is pinned, clamp the root with a pliers, and push up and down to observe.
(4) When taking the downstream wire, use a knife-shaped punch to open the opening of the hairspring ring, then the hairspring ring is loose and easy to take.
5. Repair of the hairspring
Adjusting the hairspring is very important for the pressure gauge. Pay attention to the following points:
(1) After installation, the flat surface of the hairspring is uneven, with the clamp clamped vertically at the root of the tail end, forming a skull shape, and the jaws are turned up; in a bowl shape, the jaws are pressed down, and generally can be adjusted.
(2) The hairspring is eccentric to the left, which is short outside the end-end bend; the hairspring is eccentric to the right, which is the length left outside the end-end bend, which can change the bending position or open the hairpin, and increase or decrease the work of the end portion. The length is solved. When the hairspring is up or the hairspring is eccentric downward, use the tongs to push up and down the façade at the outer end of the outer corner of the curve. If the bending angle is too large or too small, the jaws should be clamped to the right side of the bending angle to change the bending angle.
(3) When the hairspring plane is inclined, when the one side is high and the side is low, the jaws are vertically clamped to the left side of the tail end bending, and the verticality of the hairspring surface is corrected. Which side is higher than the plane, the side of the jaw is tilted and applied to the side, and corrected until the level is flat. It is also possible to rotate the pin to bring the balance spring to a flat state when the pin is not fully inserted.
