A ventilator is designed to breathe for somebody who is unable to breathe effectively on their own in layman’s words. A ventilator steps in when the lungs of a patient are inflamed and filled with fluid making it difficult to breathe with ease. Modern ventilators consist of a pump machine and a tube that health care professionals slide into your windpipe to control airflow. Ventilators help support the lung’s functions as the body fights off an infection or ailment. In the present times when the world has been gripped by the pandemic of Corona Virus, the need of the hour is an innumerable number of ventilators for patients battling the virus. DIY ventilator can come to the aid for immediate support until he is transferred to a medical facility.
Here is how you can make DIY Ventilator:
- ½ inch thick plywood 18 x 21 inches.
- 1 Inlet valve ¼ inch open valve ( with at least 50 psi rating).
- 2 ½ inch diameter valves ( one normally open and one normally closed – direct acting solenoid type)
- Threaded pipe fittings with Teflon tape on fittings
- 2 numbers ½ inch NPT Ts
- 1 number ¼ inch airline fitting (to connect to an air supply)
- 4 numbers ¼ inch pipe nipples (short pipe sections threaded at both ends)
- 3 numbers ¼ inch to ½ inch adapters
- 2 numbers ½ inch pipe nipples
- 1 number ½ inch plug (for plugging the line that will go to the manometer later)
- The bellows hinge is created by using 4 pieces of 1 ½ by 7 inches 5/8 inch plywood pieces and a 1 ½ by 1 ½ inch by 17-inch piece of wood, two 3 inch hinges and a 2 inch by 12 ½ reinforcement.
- Screw down the bottom 2 plywood pieces to the backing board to make the bellows.
- Position the other 2 plywood pieces directly over the first two, cover with the 17-inch piece of wood and clamp them together.
- Drill holes centered 2 and ¾ inches from each end to accept ¼ inch carriage bolts inserted from the bottom.
- Un-clamp and remove the top 17-inch piece of wood.
- Insert the carriage bolts from the bottom to line up the middle layer plywood pieces and clamp them again.
- Screw the hinges to middle layer plywood. Ensure that the screws do not protrude through the plywood to the bottom layer.
- Screw the other side of the hinges to the bellows lid between the lid and the reinforcing strip.
- The bag is clamped between the two plywood sections during operation using the nuts and washers on the carriage bolts.
- Attach the magnet to the end of the bellows near the sensor pole, and the sensors are attached to the sensor pole.
- Use a duct tape to attach them.
- Use a Ziploc bag to make the ventilator bag.
- Cut off the Ziploc part of the bag and insert a ½ inch plastic tubing into the center and use a tape to seal and reinforce the edges of the Ziploc bag.
- The tubing should stick out of the bag far enough to be able to be slipped over the end of the ¼ inch nipple section of piping.
- The taped seam of the bellows bag should be on the bottom plywood section.
- Install the hinged cover and then the top 17 inch section.
- Clamp together with the 4 inch long ¼ inch carriage bolts, two nuts and 2 washers.
PLC, Program, and Wiring:
- A PLC unit like the Direct Logic 06 DO-06DR from Automation Direct.
- A 24 V power supply and an on and off switch system is also needed.
- A basic program is need to open valve 1 and close valve 2.
- Wiring is required to connect the PLC connectors and power supply. Use 120 V valves.
- Wiring chart is as follows:
- X0 Top bellows mag switch
- X1 Bottom bellows mag switch
- X2 on off switch
- C0 24V
- All returns to Ground
- Y0 Unused
- Y1 Inhale valve (V2)
- Y2 Exhale valve (V3)
- Y3 Bellows fill valve (V1)
- C0 120VAC line
- All returns to line Neutral
The DIY ventilator can be seen running on the website at https://youtu.be/ahumLb8pWBc .