| 摘要 |
PURPOSE:To obtain a ring varistor which can remarkably improve noise absorb ing effect by forming a plurality of circumferential electrodes made of solderable material to the external circumference, providing the ohmic contacts to the one surface thereof and forming a plurality of plane electrodes being connected to the circumferential electrodes. CONSTITUTION:A ring varistor 20 includes a ring element body 21, plane electrodes 22 formed on one surface of element body 21 and circumferential electrodes 23 formed at the external circumference of element 21. The plane electrode 22 is divided equally into a plurality of sections depending on the number of poles of motor and the circumferential electrodes 23 is also equally divided in the circumferential direction in correcpondence to the foregoing division. The plane electrodes 22 assures ohmic contacts and are formed by a material not suitable for soldering, such as Ag, Zn, Sb, while the circumferen tial electrodes 23 is formed by a solderable material. According to this constitu tion, the electrode area becomes large since a pair of electrodes of circumferen tial electrode and plane electrode are formed as the varistor electrodes, and thereby sufficient capacitance can be attained. As a result, noise absorbing effect can be improved remarkably. |
