What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
With the rapid development of electronic technology, the integration of circuit boards is getting higher and higher, and the number of layers of circuit boards is increasing. Press-fit and fix to ensure accurate alignment during riveting and pressing. The rivets used on PCB boards are basically brass rivets. When riveting and pressing multi-layer PCB boards, metal chips are prone to appear, inner layer short circuits or foreign objects between layers, and because of the brass rivets With higher hardness and larger wall thickness, the riveted area of the PCB is thicker than the non-riveted area, which is easy to cause damage to the middle steel plate of the auxiliary tool. At the same time, the protruding rivets hinder the free expansion of the copper foil, which is easy to produce copper foil. wrinkling phenomenon. Now there are improved plastic rivets used to manufacture multi-layer PCB boards. The advantage is that no metal debris is generated, and at the same time, the tool steel plate is not damaged to the greatest extent. However, the existing plastic rivets are insufficient due to the inherent strength of plastics. When the PCB board is riveted and pressed, it is easy to deform, and the positioning is inaccurate, resulting in dislocation between layers, resulting in poor improvement of the product defect rate.
Most of the capacitors on the market have two pins, which are the connection terminals of the positive and negative electrodes of the capacitor. At present, there is a big hidden danger in these capacitors, that is, the connection between the pins and the core inside the capacitor is basically a stick-on connection. When the capacitor is working, the internal temperature rises rapidly, and the stick-type connection is unstable after being heated, and it is easy to detach Or loose.
At present, the connecting shafts of commonly used food processing knives on the market generally use square bayonet, which is not easy to install parts, and it is time-consuming and laborious when replacing parts; Increased processing costs. There is also a link structure with a circular bayonet on the market, but it is easy to loosen and not firm after the entire food processor is used for a period of time, which affects the use of the machine. Therefore, a connection structure that is easy to operate and simple to process is urgently needed.
Nuts are used as fasteners, and most of them need to be used in conjunction with gaskets in the process of use to adjust the deficiencies of the material itself and strengthen the degree of tightening, while metal materials are used as raw materials for gaskets. The cost is also relatively high, and in the process of use, the end face of the metal gasket and the nut will also be affected by the process, resulting in the defect that the fastening effect is not firm and easy to loosen.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
