In light of the ongoing Coronavirus crisis and the shortage of ventilators in Hospitals around the US and around the globe I decided to develop a homemade, inexpensive and mass-producible ventilator. Currently, the cost of a ventilator is in the thousands. This product would cost less than 50 dollars and the main component is a bag valve mask. I chose to use a bag valve mask because hospitals already have thousands of these on hand. As always, all of the files and details can be seen on my Github page. Please reach out if you have questions or comments. My number and email are below.
Instead of using a slider crank mechanism like I implemented in version one. I decided to use an oscillating rack and pinion. The pinion in the joint remains in a static position which makes the rack oscillate into and away from the bag to inflate it. To the right is an animation of the mechanism at work. I will be laser cutting the pieces and building the machine in the coming weeks.
V2 CAD Model:
Once I actually got my hands on a bag valve mask I realized that this design would not work. Due to the construction of the bag, it requires a lot of force to pump the bag this way. While it is possible to build a machine that can do it, I found it smarter to go back to the drawing board and come up with a more efficient mechanism.
How it works:
The bag valve mask is strapped into a harness. When the harness is pulled, the bag compresses and oxygen flows into a tube that would connect to an endotracheal tube. The mechanism that I designed to pull on the rope is a slider crank that would be powered by a DC motor connected to an Arduino nano. The flow rate could be controlled by slowing the speed of the DC motor. I created an animation of the slider crank mechanism in Fusion 360 which you can see to the right.