Continuing a seemingly never ending quest for smaller form factor products, Apple engineers dreamed up a compact folding pin USB adapter design with the convenience of push-button magnetic actuation, as detailed in a patent granted by the U.S. Patent and Trademark Office on Tuesday.
For all intents and purposes, Apple's U.S. Patent No. 9,077,093 for a "Magnetic rotation actuator" does the same job as the new folding style 5-watt USB power adapter first introduced to the UK market with Apple Watch. The difference is in execution.
Instead of fixed prongs, like current U.S. adapters, Apple's folding design neatly tucks away live, neutral and ground pins into its plastic housing for ultimate portability and damage prevention. Each prong pivots up from its own slot when deployed, ready for insertion into a corresponding outlet. When a user is ready to pick up and go, the prongs retract and stow flush to the adapter housing for easy transport.
Like the UK adapter, today's patent also deals with three-prong units. However, instead of a manually manipulated spring-loaded hinge, the patent describes a magnetic drive mechanism that provides low friction, low wear operation with full electrical isolation between critical internal components.
In one embodiment, drive magnets disposed on an actuator slide interact with driven magnets attached to a rotatable shaft coupled to the earth prong. The actuator itself might be a button or slide that is operatively attached to the internal magnetic drive mechanism. When the slide or button is manipulated, drive magnets attract or repulse driven magnets to translate linear force into rotational motion, thus bringing the prong shaft into position.
Internally, the adapter's design is very similar to that of Apple's new UK-style product save for a few minor details. For example, the document notes bands are used to connect the first shaft with a second shaft operable to live and neutral prongs, an operation accomplished with spring-assisted arms on Apple's shipping product.
As with other Apple patents, it is unclear if or when the company plans to apply the magnetic drive system — or UK-style manual folding design — across its international power adapter lineup. In some ways Apple's current folding pin method is superior to its now patented magnetic drive design, as the simple flip up/flip down method relies on fewer external parts and is therefore less susceptible to breakage.
Apple's magnetic drive folding power adapter patent was first filed for in April 2014 and credits Mathieu P. Roy, Cesar Lozano Villarreal, Jean-Marc Gery and Vikas K. Sinha as its inventors.