People have paid more and more attention to their health as living standards rise. More and more families deploy a variety of home medical equipments to facilitate simple health management of their family members. Blood pressure measuring device, or sphygmomanometer, has become a necessary health monitoring equipment in people's daily lives. With the development of science and technology, sphygmomanometers have become increasingly more compact, portable, and sensitive.
Nowadays, many types of portable intelligent sphygmomanometer have been developed, such as wearable sphygmomanometers for the upper arm or the wrist. These types of sphygmomanometers require cuffs (or bands) to be wrapped and fastened around the upper arm or wrist for measuring blood pressure. The cuff is typically built-in with a fluid bag for pressing arteries at certain portions of the body, such as the upper arm or the wrist. Arterial pressure wave can be detected when air is pumped into and out of the fluid bag by a built-in pump motor, so that blood pressure can be measured. Generally, the cuff includes an air bag for accommodating air and a sleeve for wrapping the air bag around the body. When wrapped around the upper arm or the wrist of a user, the cuff is also called an arm band or wrist band.
In the prior art, air bags are usually of a flat one-piece sealed rubber structure. The upper and lower rubber layers of the air bag tend to adhere to each other, therefore lowering the speed of inflation and deflation of the air bag and detection efficiency of the sphygmomanometer. In addition, poor air permeability of the rubber layers reduces the comfort of measurements.