Method and an apparatus for measuring blood pressure

DETAILED DESCRIPTION The invention comprises two devices, each separately constituting a new measuring instrument within the medical attendance for measuring blood pressure at hospitals, blood donation centres and elsewhere, where measuring blood pressure is involved in a routine for determining a person's blood pressure.
The first novelty is that the cuff consists of two parallel, inflatable intercommunicating rubber cushions.
When air is inflated the cushions will grow in a radial and tangential direction towards each other.
Thereby two fields of force are achieved, which are directed obliquely inwards against an extremity enclosed by the cuff and at the point where these cross each other an artery is positioned.
This is squeezed towards the skeleton of the extremity so that the blood ceases to flow through and the so-called Korotkoff-sounds or the pulsation are not perceptible downstream the squeeze.
The coarseness of the extremity is of less importance with this cuff, which eliminates one problem for the hospital staff.
The second novelty is the embodiment of the valve system.
The cuff is connected to a valve system with a rubber hose.
An air hand pump is also connected to the valve system, i.
e.
through the valve system a tube is running, which partly transports the air from the air pump to the cuff, partly discharges the air from the cuff via two small channels placed across the tube.
Said two small channels are of different sizes and each of them is closed by means of a rubber coated piston, each one giving the air required outflow.
Each of the pistons are operated by means of a button.
There is a smaller channel for slow, continuous emptying, and a bigger channel for rapid emptying, when the measuring is accomplished.
When the rubber cushions are inflated to a pressure which prevents the blood to pass the Korotkoff-sounds are inaudible downstreams the squeeze.
Air is now released by a press on the first button, which lifts the rubber coated piston and the smaller channel opens and a distinct, continuous air outflow starts