Constant current power supply with precise voltage function

A constant current power supply with a precise voltage function comprises a transformer, a storage battery, a motor speed reducing mechanism, a primary voltage stabilizing circuit, a high voltage detection circuit and a low voltage detection circuit. The primary voltage stabilizing circuit is matched with an adjustable resistor A, the transformer, the lithium storage battery, the primary voltage stabilizing circuit, the high voltage detection circuit and the low voltage detection circuit, the adjustable resistor A is installed in the element box and electrically connected, and a supporting frame is installed at the side end of the adjustable resistor A; the motor reducing mechanism is installed on the upper portion of the inner side end of the supporting frame, the lower end of a power output shaft and the upper side end of an adjusting handle of the adjustable resistor A are installed together, a fixing plate is installed at the side end of a shell of the adjustable resistor A, power switches are installed a