DIY Automatic ventilation for AMBU bags 3d printable / made with laser cut acrylic

grabcad

My free contribution as a Maker to the DIY movement of finding alternatives for the most needed medical supplies. Please note that this design is not definitive and that sizes of the bag is approximate, so before 3D printing the parts, they must be modified.This design compresses bags like Ambu Bags.It uses easy to find parts, like Nema 17 stepper motor, shaft coupler, linear rods. The use of high helix screw means that with 1 stepper turn, the vertical movement is 25.4mm, so cycles of 2s + 4s should be possible. The body parts can be 3D printed. A benefit of this design is that mechanical stress on the 3D printed parts is reduced as much as possible. An Arduino based PCB controls the stepper movement, amplitude and frequency of the movement, endstops sensor check that everything is moving as expected, and a buzzer can notify if something is not. Feel free to modify as you like.V2: for anyone interested, this new version that can be made with laser cut acrylic parts mostly, just a few 3d printed parts; acrylic parts can be glued together, or joined with 3d printed brackets and screws (not shown). The assembly has been simplified, endstop to check that the movement is performed correctly also added. Please note that the assembly is still WIP.