COMMUTATOR FOR VIBRATION MOTOR, VIBRATION MOTOR AND PLATING SOLUTION USED FOR THE SAME

摘要

A commutator for a vibration motor is provided to increase reliability by improving wear resistance and electrical conductivity in an interface that is electrically contacted between the commutator and a brush, a vibration motor having high electric reliability and extended life by employing the commutator is provided, and a plating solution used for coating surfaces of metal conductive segments of the commutator is provided. A commutator for a vibration motor comprises: a plurality of metal conductive segments; and an Au-Ag-In alloy layer formed on surfaces of the metal conductive segments that is electrically contacted with a brush. The metal conductive segments comprise a copper layer formed of copper or a copper alloy. The Au-Ag-In alloy layer comprises 20 to 79.9 wt.% of Au, 20 to 79.9 wt.% of Ag, and 0.1 to 10 wt.% of In. The Au-Ag-In alloy layer comprises 40 to 59.9 wt.% of Au, 40 to 59.9 wt.% of Ag, and 0.1 to 5 wt.% of In. The Au-Ag-In alloy layer is formed by performing a plating process using a plating solution comprising 2 to 16 g/L of potassium dicyanoaurate(KAu(CN)2), 2 to 10 g/L of potassium dicyanoargentate(KAg(CN)2), 0.2 to 5 g/L of indium(III) sulfate hexahydrate(In2(SO4)3-6H2O), and a water solvent. The Au-Ag-In alloy layer has a thickness of 0.5 to 5 mum. The commutator for a vibration motor further comprises at least one strike plating layer of Ni, Au, Ag, Cu, Pd, Rh, Cd, and alloys thereof formed between the metal conductive segments and the Au-Ag-In alloy layer. The commutator for a vibration motor further comprises a Ni-plating layer formed between the metal conductive segments and the Au-Ag-In alloy layer.