Vibration motors are imbalanced motors. To make the motor imbalanced, a weight is added to the center of the rotary shaft which causes the motor to vibrate. Vibration depends on the weight added on the motor, the distance between the weight and the shaft center and the speed of the motor.
Vibration motors are compact sized DC motors. They are commonly used in applications which need to notify the user without sound. These applications are generally cell phones, pagers, game consoles. A common feature of vibration motors is their having permanent magnets. Besides this, vibration motors are commonly small in size and lightweight. Due to that features their performance are reliable.
Vibration motors designs have two types. The first one is coin shaped or flat vibration motor and the second one is cylinder shaped or bar vibration motor.
