Electronic anesthesia device circuit diagram

Working principle: The circuit of the electronic anesthesia device is shown in the figure below. Since the transistor oscillator is basically a constant current source, when there are more than two groups of outputs at the same time (such as four groups), if the output amplitude of one group is larger, the output of the negative pulse part of the other groups will be reduced accordingly. This means that they will affect each other. This is very unfavorable for electric anesthesia and must be avoided. In order to eliminate this shortcoming, a voltage regulator diode is connected to both ends of the primary winding of the oscillator output transformer to play the role of limiting and stabilizing voltage. In this way, several groups will not affect each other when working at the same time, which is necessary for anesthesia work. In this way, comprehensive use can be achieved, which can be used for both treatment and anesthesia.

Since the positive pulse amplitude is obtained by stepping up the power supply voltage through the transformer, several groups of positive pulses can be superimposed (forward superposition). If four groups are output at the same time, the amplitude of each positive pulse is 60mA (on a 1kΩ load resistor), and two groups can be superimposed forward to get 100mA; three groups can be superimposed to get 130-150mA (depending on the quality of the transformer). This superposition method is not a proportional growth, nor can it be superimposed indefinitely. Generally, it is difficult to superimpose four groups, so the output amplitude can be greatly improved. You do not need to specifically pursue the size of the unilateral output amplitude, but you can increase the amplitude through superposition. It is very beneficial to use it in some special occasions (for example, if the superposition is good, it can also be used as a pacemaker).

In Figure 7.3, potentiometers RP1 and RP2 are frequency adjustment potentiometers, and the frequency can vary in the range of 2 to 50 Hz. Potentiometers RP3 to RP10 can adjust the output amplitude.

Figure 7.3