Burster

Claim 2

In a burster for separating successive sheets of paper from a continuous web along lateral perforation lines and having a pair of driven feed rollers spaced from a pair of snap rollers driven at a greater speed than said feed rollers, the improvement comprising a breaking element disposed between said pairs of rollers and having a triangular upper surface with the apex thereof horizontally aligned with the contact of said snap rollers and said triangular upper surface being inclined downwardly from the apex to the base adjacent the contact of said feed rollers and a secondary breaking unit having sides slanted inwardly and upwardly to a forward apex displaced from the apex of said triangular upper surface toward said snap rollers with said apices being horizontally aligned and also aligned longitudinally of the traverse of paper through the burster whereby paper moved by said feed rollers over said breaking element folds thereover for tearing the paper along a perforation line each time the snap rollers grip and pull the paper.

Claim 3

The improvement of claim 1 further defined by a plate from which said triangular upper surface and said secondary breaking unit extend and said plate being mounted in fixed position in said burster between said pairs of rollers.

Claim 4

The improvement of claim 1 further defined by said triangular upper surface extending laterally at the base thereof substantially entirely across the length of said feed rollers.

Claim 5

The improvement of claim 1 further defined by the contact of said feed rollers being disposed below a horizontal plane through the contact of said snap rollers and the apex of said triangular surface whereby paper is fed along the upward incline of said triangular surface by said feed rollers to fold over the apex of said triangular surface so that gripping of the paper by the snap rollers rotating at a greater rate than the feed rollers cause the paper to be torn by said apex at the center of a perforation line across the paper and progressively torn outward along the perforation line to minimize noise generation during paper separation.

Claim 6

The improvement of claim 1 further defined by said triangular upper surface having a centrally located apex directed toward said snap rollers and said surface being inclined downwardly from the apex toward said feed rollers to dispose the sides of the triangular surface which form edges of the surface extending across the path of paper between the pairs of rollers with said edges being inclined downwardly from the apex toward to the ends of the feed rollers so that paper rides on these edges in passage over the breaking element.

Claim 7

The burster of claim 1 in which the secondary breaking unit is inclined with respect to the horizontal at a greater degree than the sides of said triangular upper surface whereby paper passing over said breaking element engages the apex and sides of said triangular surface.

Claim 8

The burster of claim 6 wherein said secondary breaking unit is formed to that of a pyramid.

Claim 9

The burster of claim 6 wherein the apex of the triangular upper surface is centrally located to extend toward said snap rollers, and wherein the lateral extension of said triangular upper surface is substantially equal to the lateral extension of said feed rollers for support of the paper throughout its width dimension whereby paper moved by said feed rollers is supported in movement toward said breaking element to feed over said apex for tearing progressively the paper from a central location along a perforation line each time the snap rollers grip and pull the paper.

Claim 10

In a burster for separating successive sheets of paper from a continuous web along lateral perforation lines and having a pair of driven feed rollers spaced from a pair of snap rollers driven at a greater speed than said feed rollers, the improvement comprising a breaking element disposed between said pairs of rollers and having a triangular upper surface with the apex thereof horizontally aligned with the contact of said snap rollers and said triangular upper surface being inclined downwardly from the apex to the base adjacent the contact of said feed rollers and a secondary breaking unit in the form of a pyramid having the apex thereof horizontally aligned with the apex of said triangular surface on the side of said snap rollers therefrom and said apices being aligned with the mid-points of said rollers and separated a short distance from each other whereby paper moved by said feed rollers over said breaker element folds thereover for tearing the paper along a perforation line each time the snap rollers grip and pull the paper.

Claim 11

In a burster for separating successive sheets of paper from a continuous web along lateral perforation lines and having a pair of driven feed rollers spaced from a pair of snap rollers driven at a greater speed than said feed rollers, the improvement comprising a breaking element disposed between said pairs of rollers and having a triangular upper surface with the apex thereof horizontally aligned with the contact of said snap rollers and said triangular upper surface being inclined downwardly from the apex to the base adjacent the contact of said feed rollers and a secondary breaking unit in the form of a pyramid having the apex thereof horizontally aligned with the apex of said triangular surface on the side of said snap rollers therefrom and said apices being aligned with the mid-points of said rollers and separated a short distance from each other whereby paper moved by said feed rollers over said breaker element folds thereover for tearing the paper along a perforation line each time the snap rollers grip and pull the paper.

Claim 12

The improvement of claim 9 further defined by the sides of said secondary breaking unit being inclined with respect to horizontal at a greater degree than the sides of said triangular surface whereby paper passing over said breaking element engages the apex and sides of said triangular surface.