Big thanks to Martin for this design. it solve my issue of filament jam due to the small hook at the end of each roll of filament.
This model is for ppl with ender endstop switch and M10 bowden thread.
it requires below hardware to assemble:
two M3x10 screws
two M3 nut
a spring from ball pen
I only upload the lever part, for the remaining part, please refer to
https://www.printables.com/model/58207-super-simple-filament-jam-and-presence-sensor/files
https://www.printables.com/model/275865-super-simple-filament-jam-and-presence-sensor-inli
The author remixed this model.