A assembling structure of a miniature vibration motor includes a seat plate provided with electronic elements, a sensor, and connecting points. A conducting line is provided between the sensor and the connecting points. The seat plate is formed with a shaft hole for fixing of a pivot shaft that passes through the shaft hole of the housing and the shaft hole of the rotor. The rotor has a permanent magnet induced with the poles of the stator seat. The stator seat is wound with a coil, and has connecting legs connected to the connecting points of the seat plate. The housing may be fixed on the seat plate.
A direct current (DC) brushless vibration motor includes an inductive coil as the stator, and a magnetic element, which has a plurality of coplanar magnetic poles, as the rotor. The inductive coil is a single annular coil formed by a singly-wound conductive wire. The winding area corresponds to two magnetic poles of the magnetic element of the like polarity at opposite sides. The magnetic element has a centrifugal slot to make the gravity center of the magnetic element eccentric from the axis. When current is input into the inductive coil to form a magnetic field, the magnetic element and the magnetic field generated by the inductive coil repulse each other to generate rotation. The eccentric gravity center of the magnetic element can generate the vibration desired.
A deflection limiting member (110, 310) or a deflection limiting mechanism (512, 514) is used to limit deflection of a motor shaft (102) of a vibrator (105, 305, 505) in a portable electronic device (104,304, 504). The deflection limiting member (110, 310) extends in a radial direction from the motor shaft (102) on a side of the motor shaft (102) that is opposite to the center of gravity (108, 308) of an eccentric weight (108, 308). The deflection limiting member (110, 310) contacts a fixed surface such as a printed circuit board (112) to limit deflection of the motor shaft (102). The deflection limiting mechanism (512, 514) prevents an inertial force of an eccentric weight 510 from being applied directly to the motor shaft (102) under conditions in which there is a high risk of permanent deformation of the motor shaft (102).
Disclosed is an improved flat vibration motor to be disposed in a mobile communication terminal, etc. for generating a vibration signal. A brushless-type vibration motor without brushes and a commutator is adopted, instead of a brush-type vibration motor with the brushes and commutator. An eccentric portion is disposed on one side of the peripheral surface of a rotor made of a permanent magnet, and one or more pairs of hall sensors are mounted in the vibration motor so as to start and drive the vibration motor. A motor controller may be used as internally or externally disposed on the vibration motor. The arrangement of a stator coil is improved so as to reduce the loss of magnetic flux as well as remove the non-operation points, thereby preventing the starting and driving disorders of the vibration motor, and improving its performance and efficiency.