Trackless construction measuring instrument for overhead line system in tunnel

The utility model discloses a trackless construction measuring instrument for an overhead line system in a tunnel, and belongs to the technical field of tunnel engineering measurement. The trackless construction measuring instrument for the contact network in the tunnel is low in manufacturing cost, high in measuring precision and high in efficiency. The technical scheme for solving the technicalproblem is as follows: the technical scheme is adopted; the instrument disclosed by the utility model comprises two vertical adjusting support rods, the horizontal cross beam base is arranged on the vertical adjusting support rod; an ultrahigh adjusting clamping column is vertically and fixedly arranged on one side above the horizontal cross beam base; one end of the ultrahigh adjusting cross beamis hinged with the horizontal cross beam base; the other end of the ultrahigh adjusting cross beam is fixed to the ultrahigh adjusting clamping column, a precise sliding rail is fixed to the top endof the ultrahigh adjusting