Construction steel bar machining device

The invention discloses a construction steel bar machining device which comprises a frame. A transverse frame is horizontally mounted at one end of the inner part of the frame, a sliding frame is slidably mounted on the outer side of the transverse frame, a sliding seat is slidably mounted on the outer side of the sliding frame, a mounting frame is mounted on the outer side of the sliding seat, and a first pneumatic pressure rod is horizontally mounted at the bottom of the mounting frame. The second pneumatic pressure rod works and extends to drive a translation frame to slide on a second sliding rail, at the moment, a roller moves along a limiting piece, when the roller moves to a lifting plate, a placing frame rotates on a rotating shaft through a bearing seat, at the moment, one end ofa steel bar penetrates through a discharging groove to be in contact with the top side of the lifting plate and continuously moves along with the placing frame, the steel bar extends out continuouslyfrom the inner part of the discharging groove, when the placing frame moves to the bottom end of the limiting piece, the steel bar automatically falls into a hopper, at the moment, the second pneumatic pressure rod contracts to return to the original position, the automatic discharging operation of the steel bar is rapidly and conveniently completed, and the condition that the steel bar is damageddue to direct discharging is avoided.