How does the magnetic module of a double swivel bracket balance strong suction force with compatibility for wireless charging on smartphones?
Publish Time: 2025-09-11
With wireless charging now widely available on smartphones, magnetic mounts for cars or desktops face a key challenge: how to provide strong suction to secure the device while not interfering with the phone's wireless charging performance. The double swivel bracket, with its flexible two-axis adjustment, has become an ideal accessory for phone and tablet users, and the design of its magnetic module is the core technology. Through innovative materials, structural optimization, and electromagnetic compatibility design, the modern, high-performance double swivel bracket successfully achieves the dual goals of "strong magnetic fixation" and "unimpeded wireless charging," meeting users' comprehensive needs for safe, convenient, and efficient charging.
1. Selecting rare earth magnets with high magnetic permeability and low interference
The core of the magnetic module is the permanent magnet. Traditional ferrite magnets, while low-cost, have weak magnetic force, require a larger size to maintain proper fixation, and are prone to interference with electromagnetic signals. Modern double swivel brackets commonly use neodymium iron boron (NdFeB) rare earth magnets. Their high magnetic energy product enables powerful suction within a compact size, ensuring the phone remains secure even during bumpy driving or frequent contact. More importantly, by precisely controlling the magnet's size, thickness, and magnetic field distribution, its operating frequency is offset from the 110–205kHz band used by mobile phone wireless charging, reducing eddy current losses. Furthermore, the magnet's surface is nickel-plated or epoxy-encapsulated to prevent oxidation and provide a certain degree of electromagnetic shielding.
2. Optimizing Magnet Layout for Directed Magnetic Field Focusing
To prevent magnetic field diffusion from interfering with the charging coil, the magnetic attraction module utilizes a "ring array" or "center-spaced" layout. This involves arranging multiple small neodymium magnets in a ring around a central area, creating a magnetic-free zone in the middle that precisely corresponds to the location of the phone's wireless charging coil. When the phone is attached, the charging coil faces the magnet's gap, minimizing magnetic field interference. At the same time, the magnetic field generated by the ring magnet is focused in all directions, enhancing the edge adhesion and creating a "strong outside, sparse inside" magnetic field distribution. This not only ensures overall fixing strength but also creates a "green channel" for wireless charging. Some high-end brackets also incorporate a magnetic guide sheet (such as soft iron or silicon steel) on the back of the magnet to direct the magnetic lines of force to the adhesion surface, reducing leakage into the device and further improving charging efficiency.
To ensure seamless coordination between magnetic attraction and charging functions, the bracket features an integrated structural design. For example, precise holes are reserved in the center of the magnetic attraction module, or a thin wireless charging transmitter coil is embedded, allowing users to charge and use their phone without removing it. Some smart double swivel brackets even have a built-in Qi-certified charging module, powered by USB-C or a car power adapter, achieving "magnetic attraction + charging" two-in-one functionality. In this case, the magnet and charging coil undergo precise simulation and testing to ensure optimal matching of spacing, shielding thickness, and circuit layout. This allows for sustained charging efficiency above 75%, approaching the level of a direct charger connection.
4. Compatibility with the Mobile Phone Ecosystem: Support for Magnetic Adaptation and Universal Compatibility
Apple's MagSafe ecosystem sets the standard for magnetic accessories. Its phones feature a built-in circular magnet array that aligns perfectly with certified mounts. The Double Swivel Bracket replicates the MagSafe magnetic pole pattern for automatic alignment, ensuring precise alignment between the magnetic field and the charging coil. For non-MagSafe phones, the bracket utilizes a "universal magnetic sheet + highly compatible coil" solution. It comes with a thin magnetic sheet, typically less than 0.5mm thick, that adheres to the phone's back, ensuring no interference with wireless charging. The sheet's built-in magnet array matches the bracket's, ensuring secure attachment without obstructing the charging area.
5. Thermal Management and Safety
Wireless charging generates heat, which, when combined with magnets, can impact performance or safety. Therefore, the Double Swivel Bracket incorporates a thermally conductive barrier between the magnetic module and the charging area, or uses high-temperature-resistant materials, to prevent demagnetization of the magnets or overheating of the phone due to excessive temperatures. Some products also incorporate a temperature sensor and overheat protection circuitry to monitor charging status in real time and ensure safe use.
In summary, the Double Swivel Bracket successfully resolves the conflict between strong magnetic attraction and wireless charging compatibility through its high-performance magnets, intelligent magnetic field layout, structural integration, and ecological adaptation. It not only provides a stable and reliable device fixing solution but also adapts to the trend of wireless and intelligent use, becoming a vital accessory for modern mobile life.
