The micro dc motor is the first device to convert electrical energy into mechanical energy. It can be traced back to Faraday's invention of the disc motor. In 1880, has become the main electrical energy into mechanical energy conversion device, but due to the use of alternating current (ac) has become increasingly popular, and the invention of the induction motor and synchronous motor, dc motor, the importance of also decreases. Until about 1960 years, with the invention of the SCR, magnet materials, carbon brush, of improving insulation materials, and variable speed control of growing demand, combined with the development of industrial automation, direct current motor drive system obtained the development opportunity, again by 1980 dc servo drive system become the key to industrial automation and precision machining technology.

The characteristics of micro - dc motor.

1. The micro dc motor has the characteristic that the motor can automatically slow down according to the load, so as to achieve a great start torque. This is more difficult for ac motors. In addition, dc motor is easy to absorb the load size of the mutation, the motor speed can automatically adapt to the load.

2. The efficiency of micro dc motor is generally higher than that of other types of motors. Therefore, the volume of dc motor is generally smaller when it reaches the same output power. For the limited installation position, the micro dc motor is relatively suitable.

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   In 1880, has become the main electrical energy into mechanical energy conversion device, but due to the use of alternating current (ac) has become increasingly popular, and the invention of the induction motor and synchronous motor, dc motor, the importance of also decreases.

   By 1880, it had become the main electric power to the mechanical energy conversion device, but since the use of alternating current became more and more popular, the importance of the induction motor and synchronous motor was reduced.

   By 1880, it became the main power to the mechanical power conversion device, but since the use of alternating current became more popular, the idea of the induction motor and the synchronous motor, the importance of the dc motor was reduced.

   In 1880, it became the main power to mechanical energy conversion device, but since the use of ac power was becoming more universal, induction motor and synchronous motor were invented, and the importance of direct current motor reduced.