Abstract: A packing machine includes a supply conveyor arranged for advancing articles to be wrapped; a first motor drivingly connected to the supply conveyor; a second motor arranged for advancing a wrapper sheet codirectionally with the advance of articles; a sealing unit for periodically providing a transverse sealing seam in front of and behind each article subsequent to wrapping the article; and a third motor drivingly connected to the sealing unit. There is provided a circuit arrangement operatively coupled to the sealing unit for regulating a rotational position of the third motor. The circuit arrangement includes a computer having an input connected to the first motor for receiving data on consecutive rotational positions. To the computer there are applied data on dimensional characteristics of the articles and the wrapper sheet. The computer calculates, from the data, synchronous rotary positions of the second and third motors at least during periods when the sealing unit is in contact with the wrapper sheet.