Mini DC Brushed Motor

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Most common place to find these motors would be inside children’s toys. Mini brushed motors have very small torque and high speed of rotation, therefore are used for lightweight car toys, lightweight boat toys, small usb fans, electric toothbrushes and as a main component inside small gearmotors. As the name implies, gearmotors are these simple brushed motors combined with a number of gears. The purpose here is to reduce the speed of the rotation and consequently increase the torque of the output shaft. Great learning project here would be to use a mini brushed motor and build your own set of gears, mount them on the shaft and experiment with the output torque and speed, don’t forget to grease the gears to reduce the noise and increase the efficiency. Common working voltages for these motors are 3V, 6V and 12V. As with the other motors it’s good practice to separate the current source from the rest of the electronics, to avoid damage caused by back emf. They usually draw 0.3 A - 0.6 A, but stall current can get as high as 1.7 A, which should be taken into account when choosing a motor driver. Unloaded speed of these motors will usually be somewhere around 12.000 RPM and 18.000 RPM, the speed will decrease when the motor shaft is loaded, and decrease even more when the traction force of the fluid (water) or the ground is present. The shaft is usually 8 mm long and 2 mm in diameter. Simple press technique is enough to join the wheel or the propeller with the shaft, because these components are most likely made out of relatively soft plastic. https://www.instagram.com/robottronic/