System and method for detecting and registering serrated bags

1. A system for detecting and registering serrated bags comprising:

a) a web comprising a plurality of bags, the bags connected in an end-to-end arrangement, each bag comprising two walls, each bag of the plurality of bags comprising

i) a first side;

ii) a second side;

iii) a first longitudinal end;

iv) a second longitudinal end;

v) a transverse seal;

vi) a serration disposed transversely across the bag, and extending from the first side to the second side; and

vii) a tab cut through both walls of each bag, the tab being spaced from the first and second sides, and spaced from the first longitudinal end and second sides, and intermediate the first longitudinal end and second longitudinal end, the tab integrally connected to the bag at a portion of but less than the entire extent of the tab, and;

b) device for projecting a stream of air on each bag as the web passes a predetermined location, the device comprising a fixed roll, a source of compressed air, and an air nozzle disposed in the fixed roll,

c) a first pair of nip rolls disposed downstream of the device;

d) a second pair of nip rolls disposed downstream of the first pair of nip rolls; and

e) a detection device;

wherein the first and second pair of nip rolls are adapted to accommodate the web, and

to drive at different speeds such that a lead bag is separated from the web; and

wherein the detection device is adapted to detect a drop in air pressure as the tab of each bag passes the predetermined location, and to send a signal to the second pair of nip rolls to initiate separation of the lead bag from the web.

2. The system of claim 1 wherein the bags are patch bags.

3. The system of claim 1 wherein the tab of each bag comprises a rectangular through-cut that is attached to each bag on one side of the rectangle, and unattached to each bag on the other three sides of the rectangle.