Month: February 2012

He-arc Developed Cycloid Reducer For Automatic Winding System

Last year, Professor Professor Christian Robert, a professor of microtechnology at Heute-Arc (Haute Ecole Arc Ingénierie), and his students introduced a pendulum for displaying the hours and minutes on the watch dial. Needle wheel reducer.
This year, Professor Robert Robert also proposed to his students two new applications of cycloid pin gear reducers (also known as cycloid gear or cycloid gear reducers) in watch movements: one is to use For the automatic winding system, the other is for the seconds display.

Cycloidal pinwheel reducer for automatic winding system (model ratio 20: 1)

The main advantage of the cycloid pin gear reducer for the automatic winding system is that it replaces a large number of large and small gears on the transmission wheel system and has a high reduction factor, thereby reducing the space occupied by the movement, and The efficiency between the top and the ratchet is increased by 20%.
When applied to the automatic winding mechanism, the cycloid pin gear reducer modifies the transmission wheel system in order to reduce the rotation of the rotor to the winding of the barrel. The ratchet needs only 140 turns to rotate the rotor. The oscillating weight is free to rotate in only one direction, and pushes the cycloid pinwheel reducer in the other direction (because the cycloid pinwheel reducer can only work in one direction).

Because the movement can also be wound manually with a crown (an ETA 2892 movement is used as the basis for this mechanism), this will cause the cycloidal pinwheel reducer to rotate too fast, leading to its premature wear. Worn, the spindle-less moving element on the olive pin will act as a decoupling system to disconnect the cycloidal pin gear reducer during manual winding.
The display for the second is based on the design of the cycloid reducer which was introduced last year to reduce the display between minutes and hours. The cycloid reducer can also be used to display the seconds.