Method and apparatus for scrap removal from rotary dies
3 Assignments
0 Petitions
Accused Products
Abstract
An improved rotary die cutting apparatus and method for removing scrap material from work pieces such as paperboard blanks. One of the dies of a pair of rotary cutting dies is provided with gripper elements that extend over at least a portion of the area of the die corresponding to the areas over which the scrap portions are generated. The gripper elements grip, without piercing completely through, the scrap portions generated by the cutting operation of the dies. A stripping knife extends across the die carrying the scrap portions at a height above the gripper elements that provides clearance between the gripper elements and the stripping knife but contacts the scrap portions retained on the gripper elements.
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Citations
43 Claims
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1-19. -19. (canceled)
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20. A rotary die cutting apparatus for cutting a moving web of material having first and second opposing faces into blanks, said apparatus comprising:
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a pair of cylinders in peripheral contact;
a rotary die mounted to one of said cylinders, said rotary die having cutting elements thereon adapted to pierce both first and second faces and generate blanks and scrap portions from the moving web of material;
means for gripping scrap portions, said gripping means extending from said rotary die, sad gripping means registering with at least some of said scrap portions as said die rotates, said gripping means sized and positioned so as to pierce through the first face of the moving web and not to pierce through the second face of the moving web; and
a stripping knife having an edge for contacting said scrap portions as said sap portions are stripped away from said gripping means. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 41)
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28. A rotary die cutting apparatus or cutting a moving web of material into blanks, said apparatus comprising:
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a pair of cylinders in peripheral contact;
a rotary die removably mounted to one of said cylinders, at least one of said rotary dies having a cutting element thereon adapted to generate blanks and scrap portions from the moving web of material, the outer edge of said cutting element being located a first distance from the centerline of the one said cylinder, a plurality of gripping elements extending from he one said cylinder, said gripping elements registering with at least some of said scrap portions as said cylinders rotate, said gripping elements sized and positioned so as not to pierce completely through said scrap portions, each said gripping element having a tip located from the centerline of the one said cylinder by a distance less than the first distance; and
a stripping knife having an edge for contacting said scrap portions as said scrap portions are stripped away from said gripping elements. - View Dependent Claims (29, 30, 31, 32, 33, 34, 42)
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35. A rotary die cutting apparatus for cutting a moving web of material into blanks, said apparatus comprising:
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a pair of cylinders in peripheral contact;
a rotary die mounted to one of said cylinders, said rotary die having cutting elements thereon adapted to generate blanks and scrap portions from the moving web of material;
a plurality of gripping elements extending from the one said cylinder, said gripping elements registering with at least some of said scrap portions as said cylinders rotate, said gripping elements sized and positioned so as to partially pierce through the thickness of said scrap portions, each said gripping element being integral with each other said gripping element; and
a stripping knife having an edge for contacting the leading edges of said scrap portions as said scrap portions are stripped away from said gripping elements. - View Dependent Claims (36, 37, 38, 39, 40, 43)
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Specification