Green gear, pink large satellite gear and blue carrier create a differential planetary drive.
A pink small gear, which fixed to the pink large satellite gear, engages with a oval gear of yellow slider. A pin on the pink small gear face slides in an oval groove of the yellow slider.
The blue carrier is driving.
The yellow slider reciprocates linearly with dwell at one end of its stroke. Its speed is constant when the pink small gear engages with the straight portions of the yellow oval gear.