How should we solve some faults when the key switch is assembled? What are the common ones? Let's give you a detailed introduction.
It is difficult to slide after assembling the handle cap and the base.
Because of too many matching parts and no main matching datum, and the asymmetry of the width and center of the processing convex and groove, the key switch is offset, and the saddle shape is formed in the middle part of the rectangular groove of the handle cap due to contraction and deformation, which leads to the difficulty of sliding after assembly. In view of this situation, the matching position can be reduced, and the square hole or rectangular hole can be used as the main part of the matching. The matching clearance of convex and groove can be relaxed to avoid over-positioning. At the same time, the convex grooves in the width direction are removed from the larger base and the plane shape is modified, so that the base and the handle cap are only matched on the four adjacent sides after matching. After such improvement, the actual assembly, according to the handle cap and the base sliding fast, flexible action, feel comfortable.
The handle cap and the base are heavily tilted after assembly:
The base of the key switch restores its original shape by the elastic force of the pressure spring. Only when the elastic force of the pressure spring in the base is different and the force is uneven, can the tilt condition be produced. In a limited range, the position of the two positioning columns (including the corresponding positioning columns on the base) on the positioning rod with the compression spring can be moved upward, so that the force points of the compression spring and the conductive spring are in a basic equilibrium state. At the same time, the diameter of the steel wire of the compression spring is appropriately increased to less than 0125 mm, so that its elastic force is approximated to that of the conductive spring. After the above modification and improvement, the actual production assembly of the key switch no longer has a serious tilt situation.
The contact resistance of the switch is unstable and the electrical resistance index is difficult to pass.
Contact resistance and electrical resistance are the main performance indicators of key switch series. In view of the unstable contact resistance and low electrical resistance of key switch, the size of the relevant parts of the contact plate can be modified and improved. As a result, the R part of the contact plate is smaller, the height size is smaller, and the distance from the top of the R part to the conductive part and the center of the contact plate is changed. This not only improves the contact performance, but also has limitations. Within the effective range, the gap between the contacting parts can reach 015-016 mm, or even larger, which guarantees the attainment of the resistance index, improves the stability of the contact resistance and ensures the reliability of the product.
The above production problems not only affect the quality of key switch products, but also affect the production progress of enterprises.