Mine transportation vehicle backing-up limit alarm device

The invention discloses a mine transportation vehicle backing-up limit alarm device. The device comprises a girder, a mechanical arm, a reset device, a conduction assembly and an alarm arranged on a vehicle frame, a connecting piece is welded to the girder, the connecting piece is hinged to the top end of the mechanical arm through a first pin, the mechanical arm can swing by taking the first pinas a center, the reset device is arranged between the girder and the mechanical arm, the conducting assembly is arranged on the girder and the mechanical arm, and the conducting assembly is electrically connected with the alarm in the cab; the on or off of the conduction assembly is controlled by the mechanical arm, the potential safety hazard caused by near-distance command of the past personnelis changed, the personal injury caused by command of the dumping site personnel is avoided, the vehicle coast accident caused by the fact that the transportation vehicle is too hard to collide with atemporary vehicle stop duri