Impressive miniature engineering showcased in 3D-printed transmission.

Planetary Gearbox: Automatic Transmission Alternative with Three Gears Selected by Camshaft

Shrinking technology doesn’t just involve reducing its size; it involves preserving the fundamental purpose of the object while adapting it to fit a smaller scale. While a small manual transmission may be impressive, it becomes even more remarkable when the design complements the advanced technology employed in its creation. An ideal illustration of this concept is the miniature three-speed manual transmission crafted by YouTuber PolyProject3D.

While it may resemble a manual transmission, this mechanism actually functions more akin to an automatic one by using planetary gearsets and brake bands to adjust ratios. It differs from the traditional manual transmission design and is well-adapted for 3D printing, unlike a typical manual gearbox.

Mini 3Dprinted Transmission build

The device is not standalone; it is actually paired with another intriguing invention by PolyProject3D – a compact four-cylinder engine powered by compressed air. This pairing involves specific design elements such as a bell housing and a servo motor placed at the front in a recessed position to ensure a seamless connection between the two components.

The physical movement is carried out by the servo, which controls a camshaft with three lobes. Adjusting it to a particular position will engage a specific gear, causing one of the ring gears to stop rotating. Each ring gear being stopped results in a unique gear ratio. If none of the ring gears are stopped, then the transmission is in neutral.

The structure is an appealing fusion of mechanical and aesthetic components. It not only accomplishes a goal, but also capitalizes on its construction in the process. This equilibrium is rare and definitely deserves recognition.