APPARATUS FOR MAKING CORRUGATED TUBES Russian patent published in 2003 - IPC

FIELD: plastic metal working, namely equipment for making annular corrugations on tubes. SUBSTANCE: apparatus includes mandrel with sealing collars, die halves, holders with hydraulic cylinders for their axial motion and with mechanisms for radially drawing them together, lock units in the form of tapered straps and Г-shaped levers whose one ends are joined with hydraulic cylinder and other ends may engage with straps; axially movable power frameworks with angular supporting members arranged in plane of each holder with possibility of their common motion. Tapered straps are mounted in pairs at two sides of each holder. Г-shaped levers are joined with hydraulic cylinder by means of crosspiece placed inside framework on housing of hydraulic cylinder movably mounted relative to holder and framework. Rod of hydraulic cylinder is rigidly joined with holder. Necessary tension for drawing together is adjusted by means of cross wedge acting upon straps and by means of self-aligning rotary pin mounted on Г-shaped lever. It provides reliable drawing together of die halves, prevents friction forces caused by significant spreading efforts in contact zone of holder and hydraulic cylinder. EFFECT: enhanced quality of articles. 5 cl, 4 dwg