Turn violet lever 45 deg. and release it to make pink ratchet wheel turn 45 deg. Repeat the process for another 45 deg. The motion can be performed in either direction.
The yellow screws act as stoppers for 45 deg. rotation of the lever. Two red identical springs bring the released lever to its neutral position.
Two brass identical leaf springs force pawls (in blue and green) towards the ratchet wheel and the yellow cover.
When the lever is released, the ratchet wheel is kept immobile thanks to spring pin and cone holes on the wheel.
The mechanism can be applied for gear shifting in motorcycles.