Vivo has filed a new patent that points to work on a smarter true wireless stereo (TWS) earbuds system. If we go by the patent documents and sketches, the company appears to be exploring reverse wireless charging between the earbuds and the charging case, along with an automatic charging cut-off when a drop is detected.
The patent, titled Earphone assembly and control method, describes a charging case and earbuds that rely on internal coils rather than traditional pogo-pin connectors. Based on the drawings and descriptions, the earbuds include a coil, while the case houses its own coil, battery, processors, and a wireless charging module. This setup seems designed to allow two-way wireless power transfer, meaning the case could charge the earbuds, and under certain conditions, the system could also manage reverse charging behaviour.
Wireless charging between the earbuds and the case
If we go by the patent text and diagrams, the earbuds are charged wirelessly inside the case using electromagnetic induction between a first coil in the earbuds and a second coil in the charging case. The patent explains that the charging case uses a wireless charging module connected to these coils, allowing power to be transferred without physical charging pins.
The document also describes a forward and reverse charging module. Based on this, the system can control the direction of current flow depending on the detected state, such as when the earbuds are placed inside the case or when the case itself is being charged wirelessly from an external source. All charging control decisions are handled by processors inside the charging case.
Drop detection and charging control
One of the more interesting parts of the patent is the drop detection mechanism. Based on the diagrams, the case monitors changes in magnetic induction between the coil in the earbuds and the coil in the case. If the system detects a sudden change that indicates the earbuds or case are falling, the processor can react instantly.
According to the description, the system may either increase magnetic attraction to keep the earbuds secured inside the case during a fall or cut off charging to prevent damage. This looks like a dedicated safety feature aimed at reducing the chances of earbuds flying out or internal components being stressed during an accidental drop.
Pressure sensing and earbud removal
Based on the patent text, the charging case may also include a pressure sensor. If we go by the description, the processor can use both magnetic induction changes and pressure signals to determine when the earbuds are being intentionally removed. In this state, the system can control the coil current to increase magnetic repulsion, making it easier for the earbuds to move out of the charging case.
Note: It is important to note that this information is based entirely on a patent filing and its technical drawings. The original document is in Chinese, and all interpretations here are based on translated text and the patent illustrations. Vivo has not confirmed any product using this design, and not every patent filed by a company ends up becoming a commercial device.
