The present invention relates to a luffing jib-type tower crane comprising: a support frame installed in a rotation unit, and connected to a jib to guide the jib to vertically rotate; and a vertical drive unit installed in the rotation unit, and connected to the jib to allow the jib vertically rotate around the support frame. In addition, a top end unit of the support frame makes a hinge unit by converging towards the top side. The hinge unit of the support frame is placed on top of the end unit of the top end of a mast. The jib and the hinge unit of the support frame are combined by a hinge shaft for the jib to vertically rotate around the hinge shaft. A counterweight is mounted on one end of the jib to vertically rotate together with the jib; thereby when the jib is horizontal, a center of gravity is made on the mast since the jib and the counterweight creates a balance of force around the mast. When the jib stands up towards a top side and the center of gravity of the jib moves towards the mast, the counterweight also rotates as much as the rotation angle of the jib and moves towards the mast. As such, when the jib rotates upwards and the center of gravity of the jib moves toward the mast, the center of gravity of the counterweight also moves towards the mast, and the center of gravity of the jib and the counterweight is always placed on the mast regardless of the vertical rotation angle of the jib. The present invention aims to provide a luffing jib-type topless tower crane which allows the center of gravity of a jib and a counterweight to always be placed on a mast regardless of the vertical rotation angle of the jib whose number of parts is minimized.
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