In an email to staff, the inventor said his eponymous company had designed the “CoVent” at the request of Boris Johnson, and promised to donate 5,000 to the international relief effort.
Sir James said teams of engineers had been working solidly on the design since receiving the call from the Prime Minister 10 days ago.
The company is now waiting for the design to receive regulatory approval so manufacturing can commence.
Created in partnership with Cambridge-based science engineering firm TTP, the new ventilator had to be safe, effective, efficient in conserving oxygen and portable, Sir James said.
It also had to be bed-mounted, easy to use and not require a fixed air supply.
The battery-powered machine has been designed for use in different settings including field hospitals and when patients are being transported.
In an email to staff, Sir James said the device drew on technology used in the company’s air purifier ranges, and was powered by a digital motor.
“The core challenge was how to design and deliver a new, sophisticated medical product in volume and in an extremely short space of time. The race is now on to get it into production,” he said.
He added: “Ventilators are a regulated product so Dyson and TTP will be working with the Medicine and Healthcare Regulatory products Agency and the Government to ensure that the product and the manufacturing process is approved.
“We have received an initial order of 10,000 units from the UK Government which we will supply on an open-book basis. We are also looking at ways of making it available internationally.”
A spokesman for the company said the fan units needed for the device are already available in a very high volume.