Here’s a coronavirus story to gladden the heart: boffins at a UK-based vacuum cleaner firm have put together a working prototype for a cheap, easy-to-make ventilator to fill the massive shortage in British hospitals.
Worcester-based Gtech was responding to the government’s challenge to businesses to see if anyone could come up in short space with a suitable design.
Here Gtech tells its story:
Nick Grey, Owner of Gtech began working on the project after being contacted by Gareth Rhys Williams, Government Chief Commercial Officer, in the early hours of Sunday morning.
“At first I thought it was a hoax – being asked if I could assist in making up to 30,000 medical ventilators in as little as two weeks,” said Nick.
“When I realised that this was a genuine need I felt compelled to help”.
Nick spent Sunday learning how ventilators worked and on Monday tasked Gtech’s engineering and model making team to tackle the challenge. He also bought a ventilator off eBay and arranged for it to be collected first thing Monday morning.
There were quite a lot of problems; oxygen is a very reactive gas, which rules out many motors and electrical devices. Normal air-operated cylinders can only run on air, not pure oxygen, so they could not be used.
The breakthrough was to repurpose an everyday syringe into an oxygen-powered ram. A valve directs oxygen into the syringe which squeezes a self-inflating air container delivering 400 ml of air directly to the patients’ lungs. A second syringe acts as a timer and once the “breath” has been delivered resets the ram ready for the next cycle.
In order to save and conserve oxygen, the waste gas is fed into a reservoir to enrich the patients’ air supply.
The ventilator is driven and controlled entirely from the hospital oxygen supply without the need for electricity.
The number of cycles per minute, volume of air delivered, and the pressure of the air can all be controlled according to the patient’s needs.
“We designed the ventilator entirely from parts that can readily be made from stock materials or bought off-the-shelf. This means that if government approves and wants Gtech ventilators they can be made by almost any engineering and manufacturing company” says Nick.
“Gtech could produce around 100 per day within a week or two providing we could find steel fabrication and CNC machining companies to help us make some of the parts.”
Gtech plan to produce two more ventilators tomorrow and submit them to the government for assessment.