In the past few years, smart homes have become very popular. In recent years, smart homes with quiet, good reputation and strong applicability have once settled down in thousands of households. The next stage of the struggle should be portable medical electronic products. How to say, this global outbreak of COVID-19 has not only brought us challenges, but also brought opportunities to some innovative enterprises. Haven't you seen that portable medical products such as the forehead temperature gun have sold out, Some companies that have quietly invested in research and development in this field in the early stages have really made a lot of money in a short period of time. Perhaps the inventory that has been accumulated for several years has been emptied in one go. Are you envious? Therefore, after the dismantling of the portable urine test instrument (the demolition of the intelligent portable urine test stick HiPee) in the last issue, this issue and the non demolition bar will bring another portable medical electronic product dismantling - electronic sphygmomanometer.

Oscillographic blood pressure measurement is based on the relationship between pulse wave amplitude and sleeve pressure to estimate blood pressure, and corresponds to the maximum pulse wave amplitude with uniform pressure. Systolic and diastolic blood pressure are determined by the proportion of the maximum amplitude of the pulse wave, respectively. After the pressure reaches the set value (190mmHg in this application), the inflation pump stops pressurizing, and the solenoid valve (red) starts working, starting the linear deflation process. In the process of linear deflation, the electronic sphygmomanometer stops data acquisition and processing, and displays systolic pressure, diastolic pressure and pulse data on the LCD after the completion of the calculation. At the same time, if this sphygmomanometer has been connected to your mobile phone APP, it will also be pushed to your mobile phone via WiFi. After understanding the working principle of this sphygmomanometer, let's take a closer look at the hardware circuit plan of this sphygmomanometer.

The measurement method of pulse wave sphygmomanometer has been patented by China, Japan, South Korea, Russia and South Africa. Its accuracy is extremely high and highly recognized by many doctors and academic institutions. Its accuracy can also be verified by simple comparison. At the same time, mercury sphygmomanometer and pulse wave sphygmomanometer are used to synchronously measure the same person to verify its accuracy. This method is applicable to verifying the accuracy of all electronic sphygmomanometer.

First, remove the sleeve of the pulse wave sphygmomanometer and pull it down, without worrying about its failure.

After dismantling, you can see a pipe in front of you

Pull out the pressurized pipe from the front and pull it to the front of the sleeve.

Remove the tube used by the mercury sphygmomanometer for pressurization and the tube connecting the cuff, leaving only mercury and a tube.

Next, we need a three-way pipe and a rubber pipe, and we are optimistic about how to connect them. Next, we will focus on the key points.

Connect the end of the three-way pipe to the rubber pipe first

The other is connected to the pressure tube of the pulse wave sphygmomanometer (the tube pulled from the front of the sleeve to the front), so that the pressure in the three-way tube is the same, that is, the pressure of the mercury sphygmomanometer is the same as that of the pulse wave sphygmomanometer.