Method to make bends in the trailing ends of bars for building work in bending-shaping machines, and bending-shaping machines for bars for building work which employ such method

摘要

Method to make bends in the trailing ends of bars for building work in bending-shaping machines which comprise in working sequence a drawing and/or straightening assembly (11), a shearing assembly (16), a bending assembly (12) and clamping means (17-117), which have a first retracted position under the working plane and a second working position, the bars for building work being obtained from a bar (10) coming from a feeding section (22) possibly wound in a roll, the bar (10) with all its bends already made except a bend (24) in its trailing end being separated from the feeding section (22) and being fed forwards downstream by a required length, the bend (24) in its trailing end being then carried out in cooperation with the clamping means (17-117).Bending-shaping machine for bars for building work, which comprises in working sequence a drawing and/or straightening assembly (11), a shearing assembly (16), a bending assembly (12) and clamping means (17-117), which have a first retracted position under the working plane and a second working position, the bars for building work being obtained from a bar (10) coming from a feeding section (22) possibly wound in a roll, the machine comprising means for the controlled forward displacement (11-12) of the feeding section (22) partly pre-shaped and sheared to a required length.