Wrapping machine for wrapping a film about articles

A wrapping machine for wrapping a film about articles for forming packs containing single articles, comprising:

• conveyor means, configured for receiving and conveying articles which are to be wound about by the film according to a conveying direction;
• an aspirated conveyor belt, arranged consecutively to the conveyor means;
• a supply station of the film, comprising a reel on which a film is wound and supply and relay means for feeding the film between the conveyor means and the aspirated conveyor belt, transversally to the conveying direction of the articles, and for arranging the film with a relative central part resting on the aspirated conveyor belt and with lateral parts in relation to the central part laterally projecting from the aspirated conveyor belt, so that the articles conveyed by the conveyor means become arranged above the central part of the film arranged resting on the aspirated conveyor belt and so that the film with the articles arranged on the relative central part can be retained by aspiration by the aspirated conveyor belt and advanced in a transport direction;
• folder means, arranged and configured with respect to the aspirated conveyor belt so as to be able to abut and fold the lateral parts of the film that are laterally projecting from the aspirated conveyor belt;
• a frame associated to the aspirated conveyor belt and which is conformed in such a way as to define a tunnel-conformed frame for passage of the articles transported by the aspirated conveyor belt above the central part of the film, the folder means being conformed and configured in such a way as to abut the lateral parts of the film that are laterally projecting from the aspirated conveyor belt, during advancement thereof, and fold the lateral parts of the film about the tunnel-conformed frame so as to superpose two lateral flaps of the film and form a tube of film wound about the tunnel-conformed frame;
• glue application means, positioned above the tunnel-conformed frame and configured to apply glue on one of the two lateral flaps of the film before superposing one thereof on the other;
• heat welding and cutting means positioned downstream of the tunnel-conformed frame, at an interruption of the aspirated conveyor belt, and activatable for clamping the tube of film first anteriorly and then posteriorly with respect to the position of an article in the tube of film, so as to realise a heat-welding and cutting of the film and obtain a pack containing the article internally thereof;
• and
• photo-detecting means arranged along the tunnel-conformed frame and configured to detect the passage of the articles internally of the tunnel-conformed frame and to detect the distance between the articles and wherein the heat welding and cutting means are configured in such a way as to be non-operative when the photo-detecting means detect that the distance between two consecutive articles is less than a predetermined minimum distance.