Apparatus for the automatic ejection of concrete pipes

An apparatus for manufacturing concrete pipes comprising:

• (a) a molding flask, said molding flask comprising a cylindrical body having a bell end and a spigot end, a flange secured to said bell end of said cylindrical body and having an inside annular shoulder and an outside annular shoulder, a plurality of bolts inserted through said flange so as to allow the axes of said bolts to run parallel with the axis of said cylindrical body, a clasp rotatably fitting on each of said bolts in abutment with said outside annular shoulder of said flange, a means for constantly pressing said clasp against said outside annular shoulder of said flange, a first end ring fitting in said flange and held in place by means of said clasps, said first end ring having an outwardly projecting portion which is provided with an annular groove in the surface facing said bolts, and a second end ring fitting in said spigot end of said cylindrical body;
• (b) a device for detaching said first end ring from a concrete pipe hardened in said molding flask, said device comprising a means for subjecting said device to reciprocation in the axial direction of said molding flask, a plurality of threaded bolts arranged radially in such a manner that a plane formed thereby is made perpendicular to the axis of said molding flask and that the extension of the axis of said molding flask passes through the point where the axes of said threaded bolts intersect, a means engaging each of said threaded bolts and adapted for catching said outwardly projecting portion of said first end ring, and a means for giving a kick at said clasp, said means for giving a kick at said clasp being mounted on said means engaging each of said threaded bolts;
• and
• (c) a means for giving an inward push to said second end ring.