An interleaving unit, comprising a pair of rolls (1, 2) set alongside one another and counter-rotating and provided with respective first and second folding tools (3, 4; 5, 6) set at a distance from one another along the circumferential development of the respective peripheral surfaces so as to operate in a common point of tangency (Z) on a succession of sheets (7a, 7b) fed between the two rolls, said tools (3, 4; 5, 6) being set on respective mobile cylinder sectors (8, 9, 10, 11) to enable positioning thereof at an adjustable distance apart along the circumferential development of a corresponding roll (1, 2), said interleaving unit comprising means (M1, M2, U) for independently adjusting the speed of rotation of one or more of said sectors according to their angular position in order to reduce or increase the peripheral speed of said sectors with respect to a speed of feed (Vm) of said sheets.

An interleaving unit, comprising a pair of rolls (1, 2) set alongside one another and counter-rotating and provided with respective first and second folding tools (3, 4; 5, 6) set at a distance from one another along the circumferential development of the respective peripheral surfaces so as to operate in a common point of tangency (Z) on a succession of sheets (7a, 7b) fed between the two rolls, said tools (3, 4; 5, 6) being set on respective mobile cylinder sectors (8, 9, 10, 11) to enable positioning thereof at an adjustable distance apart along the circumferential development of a corresponding roll (1, 2), said interleaving unit comprising means (M1, M2, U) for independently adjusting the speed of rotation of one or more of said sectors according to their angular position in order to reduce or increase the peripheral speed of said sectors with respect to a speed of feed (Vm) of said sheets.

According to an embodiment, a sheet folding apparatus comprises a first roller, a second roller configured to be energized to the first roller, form a nip section together with the first roller, fold a sheet in half together with the first roller through the nip section and convey the sheet folded in half together with the first roller and a pressing force adjusting mechanism configured to be capable of increasing and decreasing a pressing force generated at the nip section. The pressing force adjusting mechanism causes a pressing force in a state of being conveying the sheet folded in half to be lower than that in a state of being folding the sheet in half.

According to an embodiment, a sheet folding apparatus comprises a first roller, a second roller configured to be energized to the first roller, form a nip section together with the first roller, fold a sheet in half together with the first roller through the nip section and convey the sheet folded in half together with the first roller and a pressing force adjusting mechanism configured to be capable of increasing and decreasing a pressing force generated at the nip section. The pressing force adjusting mechanism causes a pressing force in a state of being conveying the sheet folded in half to be lower than that in a state of being folding the sheet in half.

An interleaving unit, comprising a pair of rolls (1, 2) set alongside one another and counter-rotating and provided with respective first and second folding tools (3, 4; 5, 6) set at a distance from one another along the circumferential development of the respective peripheral surfaces so as to operate in a common point of tangency (Z) on a succession of sheets (7a, 7b) fed between the two rolls, said tools (3, 4; 5, 6) being set on respective mobile cylinder sectors (8, 9, 10, 11) to enable positioning thereof at an adjustable distance apart along the circumferential development of a corresponding roll (1, 2), said interleaving unit comprising means (M1, M2, U) for independently adjusting the speed of rotation of one or more of said sectors according to their angular position in order to reduce or increase the peripheral speed of said sectors with respect to a speed of feed (Vm) of said sheets.

A process for the production of multipage information leaflets or slips, the information leaflet provided with a booklet structure including two or more pages, the process including in sequence the steps of: loading and feeding of a ream of sheets printed on one or both sides, taking of a single sheet from the ream and gluing along an edge portion of the single sheet, multiple folding of the single sheet on itself along the glued portion to define a folded sheet, cutting of the folded sheet to define the multipage information leaflet with the pages connected one to the other only at a joining area in proximity of an edge, pressing of the information leaflet at the joining area, accumulation and collection of the finished information leaflets and optional rejecting of the leaflets which do not comply with the production specifications.

A process for the production of multipage information leaflets or slips, the information leaflet provided with a booklet structure including two or more pages, the process including in sequence the steps of: loading and feeding of a ream of sheets printed on one or both sides, taking of a single sheet from the ream and gluing along an edge portion of the single sheet, multiple folding of the single sheet on itself along the glued portion to define a folded sheet, cutting of the folded sheet to define the multipage information leaflet with the pages connected one to the other only at a joining area in proximity of an edge, pressing of the information leaflet at the joining area, accumulation and collection of the finished information leaflets and optional rejecting of the leaflets which do not comply with the production specifications.

According to an embodiment, a sheet folding apparatus comprises a first roller, a second roller configured to be energized to the first roller, form a nip section together with the first roller, fold a sheet in half together with the first roller through the nip section and convey the sheet folded in half together with the first roller and a pressing force adjusting mechanism configured to be capable of increasing and decreasing a pressing force generated at the nip section. The pressing force adjusting mechanism causes a pressing force in a state of being conveying the sheet folded in half to be lower than that in a state of being folding the sheet in half.

According to an embodiment, a sheet folding apparatus comprises a first roller, a second roller configured to be energized to the first roller, form a nip section together with the first roller, fold a sheet in half together with the first roller through the nip section and convey the sheet folded in half together with the first roller and a pressing force adjusting mechanism configured to be capable of increasing and decreasing a pressing force generated at the nip section. The pressing force adjusting mechanism causes a pressing force in a state of being conveying the sheet folded in half to be lower than that in a state of being folding the sheet in half.

A process for the production of multipage information leaflets or slips, the information leaflet provided with a booklet structure including two or more pages, the process including in sequence the steps of: loading and feeding of a ream of sheets printed on one or both sides, taking of a single sheet from the ream and gluing along an edge portion of the single sheet, multiple folding of the single sheet on itself along the glued portion to define a folded sheet, cutting of the folded sheet to define the multipage information leaflet with the pages connected one to the other only at a joining area in proximity of an edge, pressing of the information leaflet at the joining area, accumulation and collection of the finished information leaflets and optional rejecting of the leaflets which do not comply with the production specifications.