The operating principle of an air pump is somewhat similar to that of a motor, except that while a motor converts electrical energy into mechanical energy, an air pump converts electrical energy or human power into gas pressure. An air pump primarily consists of a cylinder, a steel tank, and a pressure gauge. Inside the pump, a piston continuously reciprocates, drawing air into the cylinder and compressing it. When the gas pressure reaches a preset value, the pressure gauge indicates the pressure. This entire process is controlled by a pressure regulating valve.