Wrapping machine with severing blade in crimping head

In an article wrapping machine of the type having a frame, superposed shafts geared together and mounting opposed rotary crimping heads for crimping the wrapping between articles, means for mounting a radially movable knife blade in a slot formed in one crimping head, a blade receiving recess formed in the other crimping head, and blade actuating mechanism for moving said blade into and out of said recess to sever the wrapping between articles;

• the improvement wherein each shaft mounts diametrically opposed crimping heads with both heads on one shaft carrying blades and both heads on the other shaft having recessed, said blade mounting means comprises a pair of axially spaced bell cranks pivoted to each blade carrying head at the radially inner portion of its slot, and means pivotally connecting an outer end of each of said bell cranks to the associated blade, the shaft mounting said blade carrying heads having an axial bore, said blade actuating mechanism comprising two rods movable axially in said shaft bore, the inner end of each of said bell cranks for one blade being pivotally connected to one of said rods, the corresponding bell cranks for the other blade being connected to the other rod, individual cam follower means mounted on one end of said shaft for operating one end of each rod and a stationary cam mounted on said frame for actuating both of said cam followers.

In an article wrapping machine of the type having a frame, superposed shafts geared together and mounting opposed rotary crimping heads for crimping and sealing the wrapping between articles, means for mounting a radially movable knife blade in a slot formed in one crimping head, a blade receiving recess formed in the other crimping head, and blade actuating mechanism for moving said blade into and out of said recess to sever the wrapping between articles;

• the improvement wherein said blade actuating mechanism comprises means for moving said blade radially without any substantial axial motion, the cutting edge portion of said knife blade comprising a flat plate having parallel sides with a bevel formed on one side of said plate, said bevel intersection the opposite side of the plate and teeth formed in the beveled portion of the blade, said teeth having sharpened cutting edges disposed in the plane of said bevel and extending between the sides of said plate, said teeth being relieved behind said cutting edges, said sharpened cutting edges forming a sawtooth cutting edge that zig zags between the two sides of said plate for effecting progressive cutting of the web when the blade is projected into said crimping head recess for producing a zig zag severance line across the web that has the same width as the thickness of said plate.