Pros and Cons of Brushed Motors

Introduction: Brushed motors are widely used in various applications due to their simplicity and cost-effectiveness. In this essay, we will explore the advantages and disadvantages of brushed motors, focusing on a specific brand called LeanMotor. We will discuss the rotational mechanism, driver requirements, torque characteristics, rotational speed, control options, and pricing of these motors.

Rotational Mechanism: LeanMotor utilizes a sliding contact rectification mechanism consisting of brushes and commutators to switch the armature current. This mechanism allows for efficient and reliable rotation of the motor.

Driver Requirements: One of the significant advantages of brushed motors is that they do not require additional driver devices. This simplifies the overall system design and reduces costs.

Torque Characteristics: Brushed motors offer high starting torque, which is proportional to the armature current. This characteristic makes them suitable for applications requiring a significant initial force, especially at medium to high speeds.

Rotational Speed: The rotational speed of a brushed motor is directly proportional to the applied voltage on the armature. However, as the load torque increases, the speed decreases. The maximum achievable speed is limited by the wear and tear of the brushes and commutators, typically ranging from a few hundred to a few thousand revolutions per minute (rpm). The lifespan of the brushes and commutators is also limited to several hundred to several thousand hours.

Direction Control: Reversing the rotation of a brushed motor is as simple as reversing the polarity of the pin voltage. This ease of control makes brushed motors versatile in applications requiring frequent direction changes.

Control Options: To achieve constant rotational speed, speed control using feedback from a speed sensor is necessary. However, due to the proportional relationship between torque and current, torque control is relatively straightforward with brushed motors.

Pricing: Compared to coreless motors with upgraded magnets, brushed motors are relatively inexpensive. This affordability makes them a popular choice in various industries.

Conclusion: In conclusion, brushed motors, such as LeanMotor, offer several advantages, including a simple rotational mechanism, no additional driver requirements, high starting torque, and ease of direction and torque control. However, they have limitations regarding rotational speed and lifespan due to the wear and tear of brushes and commutators. Despite these limitations, brushed motors remain a cost-effective solution for many applications.