Article synchronizing apparatus for wrapping or boxing machines

An apparatus for grouping and synchronizing articles arriving on a flow smoothing conveyor belt and leaving on a downstream conveyor belt for feeding a wrapping or boxing machine, and provided with equidistant ledges separating groups of articles, and with at least one corrector belt for transferral of the articles from the flow smoothing belt to the downstream belt, the corrector belt being driven by a variable-speed motor, characterized in that the apparatus comprises:

• (a) a detector of the ledges in said downstream belt, adapted to supply a signal at the instant when each ledge passes a predetermined position;
• (b) a first tachometer adapted to supply a signal proportional to the speed of said downstream belt;
• (c) an article-position detector for each corrector belt, adapted to deliver a signal at the instant when each article enters said corrector belt;
• (d) a microprocessor for each corrector belt, connected for receiving the signals generated by said ledge detector, from said first tachometer and from said article-position detector for the associated corrector belt, and connected for delivering a speed-control signal to the motor of said corrector belt, and programmed for controlling the speed of the associated corrector belt to a base value which is proportional to the speed of the downstream belt by a predetermined constant, and for instantaneously changing said base value of the speed by an additive corrective constant which is proportional to the product of said base speed and the position error of the article entering the corrector belt;
• (e) said flow smoothing belt being driven by a controllable-speed motor, and further comprising an auxiliary microprocessor controlling said speed proportionally to a tachometric signal coming from a second tachometer of said corrector belt.

An apparatus for grouping and synchronizing articles arriving on a flow smoothing conveyor belt and leaving on a downstream conveyor belt for feeding a wrapping or boxing machine, and provided with equidistant ledges separating groups of articles, and with at two corrector belts in sequence for transferral of the articles from the flow smoothing belt to the downstream belt, the corrector belts being driven by a variable-speed motor, characterized in that the apparatus comprises:

• (a) a detector of the ledges in said downstream belt, adapted to supply a signal at the instant when each ledge passes a predetermined position;
• (b) a first tachometer adapted to supply a signal proportional to the speed of said downstream belt;
• (c) an article-position detector for each corrector belt, adapted to deliver a signal at the instant when each article enters said corrector belt;
• (d) a microprocessor for each corrector belt, connected for receiving the signals generated by said ledge detector, from said first tachometer and from said article-position detector for the associated corrector belt, and connected for delivering a speed-signal to the motor of said corrector belt, and programmed for controlling the speed of the associated corrector belt to a base value which is proportional to the speed of the downstream belt by a predetermined constant, and for instantaneously changing said base value of the speed by an additive corrective constant which is proportional to the product of said base speed and the position error of the article entering the corrector belt.