A spring pin, also called a Pogo Pin, is a pin with compression elasticity. Its basic structure consists of a turning needle tube, a turning needle head, and a compression spring. It is mainly used for precision connection in electronic products and plays a conductive role.

Pogo pins are widely used, ranging from space shuttles and high-speed trains to smart watches, Bluetooth headsets and other electronic products. They are also used in mobile phones, computers, printers, GPS positioning devices, communication equipment, medical equipment, aviation equipment, electronic cigarettes, etc.

- Pin stuck problem: may be caused by problems with the needle tube and needle structure design, solid glue or colloid residue, flux contamination, poor surface plating process, debris stuck, poor assembly process, improper working stroke, etc. - Poor contact and instantaneous disconnection problem: The reasons include poor quality and thickness of the electroplating layer, the working stroke and connection spacing in the spring pin structure design do not match, temperature difference changes in the external environment, vibration and other factors, unreasonable circuit design, improper material selection, special requirements of the use scenario such as contact with sweat, etc., resulting in oxidation or corrosion of the electroplating layer.

- Optimize the structural design of needle tube and needle head. - Ensure that there is no glue, flux, etc. that contaminates the spring pin during the production process. - Ensure the quality of surface electroplating process to avoid excessive roughness of the tube wall. - Standardize the production process to prevent debris or debris from entering. - Improve the assembly process to avoid damage to the tube mouth. - Reasonably control the working stroke, and the compression amount is generally 2/3 of the total stroke.

- Choose spring pins that are suitable for the product contact spacing working height. - According to the product application environment, choose the appropriate surface plating treatment. For example, for products that contact the skin, consider the biocompatibility of the plating layer. - For problems caused by circuit design, adjust circuit parameters such as voltage, current, etc.

- Tin plating: relatively cheap, soft texture, requires high contact force to ensure conductivity, low plug-in and pull-out times, not wear-resistant, can only play a simple anti-corrosion role, brass or bronze tin plating working temperature can reach 110℃, steel tin plating can reach 190℃. - Gold plating: used for spring pins that require high reliability, transmit small signals and have low contact force, chemically inactive, not easy to oxidize, and has good corrosion resistance.

A small DC charging gun is a device used to provide DC fast charging for electric vehicles and other devices. Compared with traditional DC charging guns, it is usually "miniaturized" in terms of size, weight or power, making it easier to operate and adapt to some specific scenarios. It can convert external AC power into DC power and transmit it directly to the vehicle battery pack for fast charging.

- Size and weight: Small DC charging guns are generally smaller and lighter, making them easier to plug in and out and operate, especially for people with less power, such as female users; regular DC charging guns may be larger and heavier. - Power: Small DC charging guns have relatively low power, but can meet basic daily fast charging needs; regular DC charging guns have a wider power range, and some high-power ones can achieve ultra-fast charging. - Applicable scenarios: Small DC charging guns are suitable for installation in places with limited space, such as residential areas, small parking lots, etc.; regular DC charging guns are more common in large charging stations, highway service areas, and other scenarios.

The charging speed is affected by many factors. For example, the power of a common small DC charging gun is around 20-60kW. Generally speaking, it can replenish a considerable amount of power for an electric vehicle in about 30 minutes to 2 hours. The specific time varies depending on the vehicle battery capacity and initial power. In addition, the acceptance capacity of the vehicle battery will also affect the charging speed. For example, the battery performance will decrease in a low temperature environment, and the charging speed will slow down.

As long as the vehicle's charging interface is consistent with the interface standard of the small DC charging gun and the vehicle supports DC charging, it can be charged with the small DC charging gun. Currently, most pure electric vehicles and some plug-in hybrid vehicles on the market support DC charging, such as Tesla Model 3/Y, BYD Han EV, Xiaopeng P7, etc.