Locking device for the trigger of a pistol

A locking device for the trigger of a pistol comprising a first and a second clipping seat, wherein the first clipping seat is provided with a hollow seat having a stopping block mounted with a plurality of ratchet wheels, the second clipping seat is provided with a locking seat and a geared-shaft slot, and a number combination locker is provided to the locking seat, a geared-shaft is provided to the geared-shaft slot and is mounted with a plurality of ratchet wheel, and the geared-shaft is adaptable to the hollow seat, a cut face is provided to a circular end of the geared-shaft, and a top face of the geared-shaft is provided with a rotating button, such that when the cut face is restricted by a control board of the number combination locker, the geared-shaft cannot be rotated and a trigger is at a locking position, and when number wheels of the number combination locker is rotated to a correct number, the control board is free to retract and the cut face of the geared-shaft is not engaged with the control board, the geared-shaft is then free to rotate, and the ratchet wheel of the geared-shaft and the ratchet wheel with a stopping block is thus disengaged and the trigger is at an unlocking position, the number combination locker comprises a plurality of numeral wheels, a retractable shaft, a control board, a plurality of spring, and a covering plate, the control board is controlled by the numeral wheels of the number combination locker to urge the control board to press against the cut face of the geared-shaft, the control board is controlled by the numeral wheels of the numeral locker to urge the control board to release from pressing against the cut face of the geared-shaft, a plurality of springs are provided at one lateral edge of the control board, a hole is provided to a lateral edge of the numeral locker which allows the insertion of a sharp pointer to retract the retractable shaft in order to set a number combination for the number combination locker.