Automatic wrapping machine

A machine for wrapping products (P) consisting of a plurality of cylindrical articles (R), comprising:

• first feeding means (1-2) of feeding the product (P) to a first conveyor (3-103-4-5) which moves the product in a longitudinal direction substantially coinciding with the longitudinal axis of the articles (R) and which delivers the product (P) onto elevator and counter-elevator means (22-22') for raising the the product therefrom;
• wrapper feeding means (16) for feeding a wrapper sheet (15) in the longitudinal direction above the product carried by said first conveyor (3-5) so that said product (P) is delivered to said elevator and counter-elevator means with the wrapper sheet (15) positioned thereon, said wrapper sheet (15) presented side flaps (115, 215) drooping at sides of the product;
• a guide channel (30-31-30'-31') receiving the product and wrapper sheet (P, 15) from said elevator and counter-elevator means (22-22'), and continuing the advancing movement of same in the longitudinal direction, said guide channel presenting lower fixed guide members (41) for correctly supporting the product (P);
• first folding means (43-43'-46) for folding the wrapper side flaps (115-215) onto a bottom of the product (P) causing the superposition of edges of said side flaps;
• first sealing means (53) for sealing together the superposed edges of the side flaps (115-215), thus giving origin to a tubular shaped open ended wrapper enclosing the product (P);
• rotating means (59-60-61) for imparting to the product enclosed in the tubular shaped open ended wrapper a 90.degree. rotation, and for continuing its advancement in the longitudinal direction, so as to subject open ends of the tubular wrapper to the action of a second folding means (63-64-65) and a second sealing means (66-67);
• said first feeding means comprising a guide (3) presenting an ascending stretch (103), such that into an initial portion of said guide a suitable means (1-2) feeds cyclically the product (P) which is timely engaged by one of a plurality of cross bars (4) of a parallel-chains conveyor (5) which carries said product longitudinally along said guide;
• said wrapper feeding means comprising opposite feeding belts (16) which transport, longitudinally and above the product being advanced on said guide (3), the wrapper sheet (15) having been severed by cutting means (17) from a film unwound from a reel (21), in such a manner that at an end of the ascending stretch (103), the wrapper sheet is suitably positioned on said product and is held laterally by said opposite feeding belts (16);
• said elevator (22) and counter-elevator (22') means being provided at the end of the ascending stretch (103), whereby the product (P) is positioned on an elevator (22) thereof and is held thereon by a counter-elevator (22') thereof which timely clamps on said product the wrapping sheet (15) released by the opposite feeding belts and whose side flaps hang down on a perimeter of said product, which product is progressively raised by the elevator and counter-elevator acting as a unit and which is introduced into said guide channel which is aligned longitudinally, whereafter said elevator/counter-elevator unit is deactivated and repeats a new working cycle;
• said guide channel comprising a pair of moving lateral flat belts (30-30') having an outer face with high-friction coefficient, and comprising at its sides a pair of moving round-section lateral lower belts (31-31') which progressively are inserted below the product, these lateral lower belts being synchronized with the lateral flat belts, and said guide channel being provided at its bottom with stationary, round-sectioned said guide members (41) parallel to said lateral flat and lateral lower belts, which said lateral flat and lateral lower belts engage the product in lower empty spaces between the adjacent cylindrical articles and which are mounted so that end portions thereof are overhanging to avoid interfering with the elevator (22) and to avoid interfering thereafter with the first folding means which act on the wrapping sheet;
• said first folding means (43-43'-46) acts below the product moving along said guide channel and spreads the opposite side flaps (115-215) of the wrapping sheet onto the bottom of said product, so as to superpose said side flaps and to form the tubular shaped wrapper;
• said first sealing means comprising opposite pairs of opposite upper and lower conveyor belts (48-48'-51-51') acting on the product as it leaves said lower guide members (41) and is still held laterally by the lateral flat and lateral lower conveyor belts (30-30'-31-31'), a lower portion and an upper portion of the product with the tubular shaped wrapper being engaged by said opposite pairs of said opposite upper and lower belts (48-48'-51-51') which travel in the same direction and at the same speed as said lateral belts, one of said opposite lower belts being arranged so as to engage the superposed flaps of the tubular-shaped wrapper, being made of suitable heat-transmitting material, and being urged against said sheet by heating means (53) which effect the continuous heat-sealing of said superposed flaps;
• and
• said rotating means comprising a station (57) which takes over the product thus sealed in a tubular open ended wrapper and which, while advancing it in the original longitudinal direction of travel, causes its rotation 90.degree. about a vertical axis, to subject the open ends of the tubular wrapper to the action of said second folding means, (63-63'-64-65) and of said second sealing means (67-67') to finally close the said open ends of the tubular wrapper.