Abstract: A dual drive signature stacker having side-by-side stacker sections, each of substantially identical design and including a stepper motor for driving a pair of buckets for receiving signatures secured at spaced intervals along a drive chain driven by the stepper motor. The buckets have intercept blades supported by brackets joined to the drive chain to position one of the intercept blades of each drive assembly in front of the adjacent drive assembly so that all of the buckets of the dual drive assembly are in alignment with one another and with the signature stream. The side-by-side arrangement greatly simplifies the design cost and assembly. A microprocessor-based control system permits stacking of stacks having as few as two signatures and is further capable of forming successive signature stacks of differing count in a precision manner and compatible with the speeds of any signature flow rate.

Abstract: A dual drive signature stacker having side-by-side stacker sections, each of substantially identical design and including a stepper motor for driving a pair of buckets for receiving signatures secured at spaced intervals along a drive chain driven by the stepper motor. the buckets have intercept blades supported by brackets joined to the drive chain to position one of the intercept blades of each drive assembly in front of the adjacent drive assembly so that all of the buckets of the dual drive assembly are in alignment with one another and with the signature stream. The side-by-side arrangement greatly simplifies the design cost and assembly. A microprocessor-based control system permits stacking of stacks having as few as two signatures and is further capable of forming successive signature stacks of differing count in a precision manner and compatible with the speeds of any signature flow rate.

Abstract: A stack of signatures is delivered to a weighing platform which measures bundle weight. A stored bundle weight is subtracted from the measured bundle weight to yield a difference which is compared against the stored reference weight of an individual signature. If the difference is a multiple of the weight of an individual signature, an indication of a count error is given. If the aforesaid difference is greater than the weight of an individual signature but is not an integral multiple of that weight, an indication of a possible combination error is given. If the difference is less than the weight of an individual signature, a recalibration is initiated to substitute the reference weight per unit with a new value prior to initiation of the next measuring cycle. In the presence of a combination error pattern, a manual count check is made on the subsequent sample to insure a correct count and a recalibration is then initiated.