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In this paper, combined with the characteristics of spiral-shaped transverse magnetic field (TMF) contacts and cup-shaped TMF contacts, a new structure of spiral-cup shaped contacts was designed. Firstly, experiments were carried out on two kinds of TMF contacts – the traditional cup shaped contacts and the new spiral-cup shaped contacts. Arc behaviors were recorded and the arc motion were studied. The experimental results indicated that the arc motion between new contacts was better than that between the traditional cup-shaped contacts. Here, we paid particular attention to the arc characteristics between spiral-cup shaped TMF contacts. The duration and threshold current of different stages with different tested currents were discussed, and the arc characteristics during arc motion stage was analyzed. Moreover, electromagnetic field simulation was conducted on above two kinds of TMF contacts, and the distributions of magnetic field and the electromagnetic forces acted on arc were compared. According to the simulation results, some experimental phenomena were explained theoretically. In addition, the spiral-cup shaped structure proposed here makes it possible to research on arc movement mechanism without considering the complex mechanism of arc stepping over slots.