Multi-spoke-type ultrasonic motor

A multi-spoke-type ultrasonic motor, comprising:

• a rotating shaft (1), a fastening sleeve (2), a spring (3), a rotor (4), a stator (5), a fastening screw (6), and piezoelectric ceramics (7), wherein the rotor (4), the stator (5), the spring (3), and the fastening sleeve (2) are sequentially connected by using the rotating shaft (1);
• the fastening screw (6) is located in the middle of a side surface of the fastening sleeve, and the fastening screw (6) is adjusted to make the fastening sleeve (2) slide on the rotating shaft (1), to adjust a pre-pressure of the spring (3);
• the spring (3) is between the fastening sleeve (2) and the rotor (4), and is pressed on a surface of the rotor (4);
• the rotor (4) is hemispheric or tapered;
• the stator (5) is an annular metal sheet internally provided internal spoke-like teeth, both an upper surface and a lower surface of the stator (5) are provided with identical spoke-like teeth for contacting the rotor (4), and the rotor (4) and the spoke-like teeth of the stator (5) are in close contact under the effect of the pre-pressure of the spring (3);
• and the piezoelectric ceramics (7) are flat annular sheets, and an upper sheet and a lower sheet are separately affixed to an annular surface of the stator (5), wherein there is an angle between the internal spoke-like teeth of the stator (5) and a stator ring surface on which a tooth root is located, and the internal spoke-like teeth of the stator (5) are rotationally symmetrical about a center of the stator ring surface.