A microcomputer-based CPR system design (1)

1 Introduction

We all know, the time in minutes for critical emergencies, accidents of dying patients.

Using the traditional artificial respiration and chest compression methods, often as not, firmly press the site the right way, the press depth control, press the frequency patterns and other factors, it is difficult to achieve the desired effect, and even cause fractures, pneumothorax, hemothorax and other serious complications and, at the mouth for artificial respiration is also possible in patients with sexually transmitted diseases among the ambulance. It is therefore necessary to develop rapid, accurate positioning emergency, press the appropriate portable intelligent cardiopulmonary resuscitation machines. Their timeliness and accuracy can significantly improve treatment efficacy, better solve the unarmed cardiopulmonary resuscitation. Currently the most widely used is the United States of Michigan Instruments company "SA Bo" cardiopulmonary resuscitation machines, the domestic market has still not made portable cardiopulmonary resuscitation machines. This article describes is a microcontroller to control core Cygnal portable smart CPR system.

2 single CPR system composed of

System chart:

　　

Diagram 1 for ventilation ducts, open the valve, 2 3 gas cylinder, 4-regulating valve, solenoid valve, 6 5 pressure sensor, 7 single-chip controller, 8 solenoid valves, piston cylinder 9, 10, 11, 12, head, 14 13 electromagnetic valve, solenoid valve.

System workflow is as follows:

1. adoption of the touch screen, set the microcontroller parameters: press pressure, pressure frequency;

2. open the valve 2 open, 3 pneumatic cylinders;

3, pressure regulating valve 4, solenoid valve 5 open, press 9 to start charging cylinder;

4. pressure transducer 6 cylinder pressure not to be?, you continue to charge;

5. pressure transducer 6 cylinder pressure reaches a preset, solenoid valve, solenoid valve 5 off 8 open;

6 cylinder 9 exhaust, then go to step 3 cycle;

In order to achieve the purpose, the system for portable use high pressure oxygen as the driving force.

Double cylinder, a gas cylinder to another cylinder with piston, promote the piston through the gas to massage the chest. As the piston down spring-loaded, so pressing depth and apply pressure to the pressure, the pressure increases the deeper. In-cylinder pressure reaches a preset, open solenoid valve exhaust, from here you can control the size of pressing pressure. Pressure regulating valve by stepper motor control their actions, can be adjusted to the cylinder filling of gas pressure, the pressure regulating valve vacuum pressure of gas, is equipped with a piston filling fast, while slowly. From here you can control the frequency of the press. Cylinder displacement of 50 is a bezel, prevent the piston down, allowing the sharing of part of the cylinder wall. Press the maximum depth of 50mm, can effectively prevent pressing depth too deep, rib fractures.

Through the solenoid valve discharges to oxygen 8, according to the 5: 1 compression ratio of breathing [5], by opening and closing the valve 13 and 14 of the solenoid valve to control.

Solenoid valve open, 13-14 by closed solenoid valve, pipe for ventilation, the tidal volume available add-ins to control the balloon. Solenoid valve closed, 13 of 14 of the solenoid valve is opened, the oxygen emission to the atmosphere.

3-chip control system hardware design

This system is intended to be a United States company C8051F020 SCM CYGNAL.