Multi-flap standing wave type ultrasonic motor

#The present invention relates to an ultrasonic motor, and in particular, to a multi-flap standing wave type ultrasonic motor.

#Ultrasonic motors are motors with a new drive principle, and compared with conventional electromagnetic motors, ultrasonic motors do not use coils, and employ the inverse piezoelectric effect of piezoelectric ceramic and friction coupling between a stator and a rotor to achieve energy conversion from electrical energy to torque output of the motor. Compared with the electromagnetic motor, the ultrasonic motor has the characteristics of fast response, high torque at low speed, self-locking upon no input, and electromagnetic interference free. The current standing wave ultrasonic motor has an inner-rotor flap structure, but the inner rotor structure has a complex process, the processing precision of parts cannot be ensured in batch production, enough power cannot be generated, and the inner rotor structure cannot be applied.

#The stator of the current ultrasonic motor employs an integrated multi-flap structure, so that the structure is complex and is difficult to process.

#The disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the disclosure, and wherein:

#FIG. 1 is a schematic structural diagram of a multi-flap standing wave type ultrasonic motor;

#FIG. 2 is a schematic diagram of a rotor part of a multi-flap standing wave type ultrasonic motor;

#As shown in FIG. 1 to FIG. 3, a multi-flap standing wave type ultrasonic motor of the present invention includes a rotor part 10, a stator part 20, a control circuit board 30 and a fixing attachment 40. As shown in FIG. 2, the rotor part 10 includes a flange 11, a rotor ring 12 and a shaft 13, where the shaft 13 and the flange 11 are joined together by using a screw 81 and the flange 11 and the rotor ring 12 are joined together by using a screw 82. As shown in FIG. 3, the stator part 20 includes a piezoelectric ceramics 21, an excitation ring 22 and flaps 23, where the piezoelectric ceramics 21 and the excitation ring 22 are fixed with glue, and the flaps 23 and the excitation ring 22 are connected through welding, and form an angle with the radial direction of the excitation ring. As shown in FIG. 1, the stator part 20 is sleeved on a support 41, is attached to a pressure plate 42 and is connected, through an upright 44, to a locking plate 43, and to a substrate of the control circuit board to form the fixing attachment 40, and the flap 23 is an elastomer and a preload provider. The inner diameter of the rotor ring 12 is less than the outer diameter of the flaps 23. The shaft has no bearing thereon, and performs sliding friction in the inner hole of the support, the surface of the flange fits the upper surface of the support, and the rotor is fixed in the axial direction on the other surface of the support through an external retaining ring for shaft on the shaft.

#The flaps 23 are made of an elastic sheet material, form the preload on the surface of the rotor, and form an angle with the radial direction of the excitation ring so as to promote the rotor to move in the inclined direction of the flaps.

#A photoelectric sensor 31 is installed in the circuit, so as to determine the rotational angle of the rotor by detecting the outer circle of the rotor, thereby achieving precise operation.