A forcipate gear open-close mechanism comprises a circular base spliced by two parts, an annular gear spliced by two parts, and an open-close device for driving the circular base and the annular gear to open or close. An annular guide rail formed by splicing is arranged on the circular base; the annular gear is mounted on the annular guide rail; and a power transmission device drives the annular gear to rotate along the annular guide rail. The annular gear and the circular ring-shaped base are each spliced by two parts; therefore, the gear mechanism can be clamped on an iron core conveniently, and a coil can be wound on a three-dimensional iron core conveniently. Moreover, the gear mechanism can not only be clamped on an iron core, but also be clamped on a columnar iron core.