Abstract: An interfolding machine produces interfolded sheets according to an interfolding configuration and, starting from a web of paper provides a feeding section, which applies a tension on the web and moves the same along a feeding direction feeding the same to a cutting section, in which the web of paper is cut into a series of sheets at a cutting point between a cutting roller and a counter-cutting element. Downstream of the cutting section, a folding section includes a first and a second folding rollers counter-rotating with respect to each other. The first and second folding rollers rotate about respective rotation axes with a first peripheral velocity vP, and fold, at a folding zone, a plurality of sheets in a plurality of panels and form the stack of interfolded sheets. The cutting roller alternately distributes the aforementioned sheets between a transfer roller and the first folding roller.

Abstract: Folding or interfolding unit of a web, or sheet, of paper, comprising a first and a second folding or interfolding roll, of a web, or sheet, of paper, configured to fold or interfold, the web or sheet of paper according to a predetermined folding or interfolding configuration, at a folding or interfolding zone arranged between the first and the second folding or interfolding roll. The folding or interfolding unit comprise, furthermore, a first and a second plurality of detaching fingers configured to cause the web or sheet of paper to be detached from the external surface of the respective folding or interfolding roll.

Abstract: A suction roll of a web, or sheet, of paper, includes a tubular body that rotates about a longitudinal rotation axis. External and internal lateral surfaces of the suction roll pneumatically communicate with each other through suction holes. The roll includes a suction chamber pneumatically connected to a vacuum generation device for generating a predetermined vacuum degree. A vacuum distribution device selectively puts into pneumatic communication the suction chamber with at least one row of suction holes, at determined angular positions of the tubular body and causes the processed sheet or web of paper to be sucked, and to adhere at a corresponding portion of the external lateral surface arranged between a catching point and a releasing point having determined angular positions. A displacement device moves the vacuum distribution device to change the angular position of the catching or releasing point of the web or sheet of paper.

Abstract: A folding, or interfolding, unit, for folding, or interfolding, a first and a second plurality of sheets of paper in a machine for converting paper, comprises a first and a second folding, or interfolding, counter-rotating rolls configured to rotate about a respective longitudinal rotational axis and providing a plurality of suction holes. A vacuum generation device and a vacuum distribution device are, furthermore, provided for selectively putting into pneumatic communication the vacuum generation device with at least a row of the aforementioned suction holes. The folding, or interfolding, unit, comprises, furthermore, a first and a second cutting device providing, respectively, at least a first and a second cutting blade which cooperates with a first and a second plurality of counter-blades distributed along the folding, or interfolding rolls in order to cut a first and a second web of paper, in the first and in the second plurality of sheets.

Abstract: An interfolding machine (1) for producing stacks (100) of interfolded sheets according to a predetermined interfolding configuration, starting from a web (50) of paper, or similar materials, provides a feeding section (10), which provides to apply a tension on the web (50) and to move the same along a feeding direction (101) to feed the same to a cutting section (20), in which the web of paper (50) is cut into a series of sheets (11) of length predetermined, at a cutting point arranged between a cutting roller (25) and a counter-cutting element (26). Downstream of the cutting section (20) a folding section (30) is provided comprising a first and a second folding rollers (31,32) counter-rotating one with respect to the other.

Abstract: A folding, or interfolding, unit, (100) for folding, or interfolding, a first and a second plurality of sheets of paper (105a, 105b) in a machine for converting paper, comprises a first and a second folding, or interfolding, counter-rotating rolls (1a, 1b) configured to rotate about a respective longitudinal rotational axis (110a, 110b) and providing a plurality of suction holes (11a, 11b, 12a, 12b). A vacuum generation device and a vacuum distribution device (40a, 40b) are, furthermore, provided for selectively putting into pneumatic communication the vacuum generation device with at least a row of the aforementioned suction holes (11a, 11b, 12a, 12b).

Abstract: A roll (1) for folding, or interfolding, a web, or sheet, of paper, (100) fed along an advancing direction in a paper converting machine, or similar machines, comprises a tubular body (10) configured to rotate about a longitudinal rotation axis (101), and having an external lateral surface (11) and an internal lateral surface (12) pneumatically communicating through a plurality of suction holes (3a, 3b) organized in a predetermined number of suction groups (60). Each suction group (60) comprises a predetermined number of close longitudinal rows (30a, 30b) of suction holes (3a, 3b) distributed along the tubular body (10). A suction chamber (20) is, then, provided arranged internally to the roll (1) for folding, or interfolding, and pneumatically connected to a suction device generating a predetermined vacuum level.