A system with an interfolding machine, a method and an interfolding machine

Abstract

A system comprising an interfolding machine with a frame and an interfolding unit comprising a set of roller units removably housed and independent of one another in seats of the frame, a second set of roller units, interchangeable with the set and couplers for coupling to one another respectively the roller units of the set and of the second set. Each roller unit comprises a first part and a second part and a rotatable roller. Both the couplers comprise a structure and connecting means for connecting the first part and the second part of each roller unit to the respective structure and are configured to keep the first and second parts in the positions in which they engage the frame. A method for the cut-off change and an interfolding machine.

1 . A system comprising an interfolding machine for production of interfolded packs of sheet articles from strips which comprises a frame and an interfolding unit, for cutting sheet articles from strips and for arranging the sheet articles so as to realise interfolded packs, which comprises a set of roller units, having a first roller unit and a second roller unit the rollers of which are configured for moving sheet articles, and folding elements cooperating with the first roller unit and the second roller unit in order to arrange the sheet articles in an interfolded way, wherein:
 each roller unit of the set comprises a first part, a second part and, between them, a roller which is rotatable with respect to the first part and to the second part about a respective rotation axis;   the first part and the second part of a roller unit of the set are distinct respectively from the first part and from the second part of another roller unit of the set;   the frame comprises, for each roller unit of the set, a first seat which removably houses a respective first part and a second seat which removably houses a respective second part;   the system comprises a second set of roller units which is interchangeable, in the interfolding machine, with the set and which comprises a third roller unit and a fourth roller unit interchangeable respectively with the first roller unit and the second roller unit so as to cooperate with the folding elements, each roller unit of the second set comprising a first part removably engageable with a respective seat of the first seats, a second part removably engageable with a respective seat of the second seats and, between them, a roller which is rotatable with respect to the first part and to the second part about a respective rotation axis and the first part and the second part of a roller unit of the second set being distinct respectively from the first part and from the second part of another roller unit of the second set;   the rollers of the third roller unit and of the fourth roller unit differ from the rollers of the first roller unit and of the second roller unit so as to operate with a different length of sheet articles;   the system being characterised in that it comprises a first coupler for reciprocally coupling the roller units of the set and a second coupler for reciprocally coupling the roller units of the second set, wherein:   the first coupler comprises a structure which is configured to support the weight of the roller units of the set and connecting means for connecting the first part and the second part of each roller unit of the set to the structure so as to be able to move the roller units of the set together;   the second coupler comprises a second structure which is configured to support the weight of the roller units of the second set and second connecting means for connecting the first part and the second part of each roller unit of the second set to the second structure so as to be able to move the roller units of the second set;   the first coupler is configured in such a way as to maintain the first parts and the second parts of the roller units of the set in the positions they reciprocally occupy when they engage the first seats and the second seats;   the second coupler is configured in such a way as to maintain the first parts and the second parts of the roller units of the second set in the positions they reciprocally occupy when they engage the first seats and the second seats.   
     
     
         2 . The system of  claim 1 , wherein the interfolding machine is configured in such a way as to enable lifting the roller units of the set together. 
     
     
         3 . The system of  claim 2 , wherein the frame comprises a first upper part which bears idler rollers and/or drive rollers, a second upper part which bears idler rollers and/or drive rollers and a lower part which has the first seats and the second seats, wherein the first upper part and the second upper part are both hinged to the lower part and wherein the interfolding machine comprises at least an actuator which moves the first upper part and the second upper part between a first operating position and a second maintenance position in which the first upper part and the second upper part free the space above the roller units of the set so as to enable the lifting thereof. 
     
     
         4 . The system of  claim 3 , wherein the at least an actuator comprises a first hydraulic or pneumatic cylinder which is connected to the first upper part and to the lower part so as to move the first upper part and a second hydraulic or pneumatic cylinder which is connected to the second upper part and to the lower part so as to move the second upper part. 
     
     
         5 . The system of  claim 1 , wherein the connecting means comprise screws and the structure comprises openings in which the screws engage. 
     
     
         6 . The system of  claim 1 , wherein the interfolding machine comprises blades, or counter-blades, wherein the set of roller units has two cutting roller units which cooperate with the blades, or counter-blades, for cutting sheet articles from strips and wherein the structure comprises a central part which is configured to support the first parts and the second parts of the first roller unit and of the second roller unit and wings which project from the central part on opposite sides and which are configured to support the first parts and the second parts of the two cutting roller units. 
     
     
         7 . The system of  claim 1 , wherein the interfolding machine comprises blades, or counter-blades, and wherein the first roller unit and the second roller unit cooperate with the blades, or counter-blades, for cutting sheet articles from strips. 
     
     
         8 . A method for varying a length of sheet articles of interfolded packs of sheet articles produced from strips in an interfolding machine comprising steps of:
 providing a system according to  claim 1 ;   replacing the set of roller units with the second set of roller units;   wherein in the step of replacing the set of roller units, the roller units of the set are connected to the structure with the connecting means and the roller units of the second set are connected, or are already connected, to the second structure with the second connecting means.   
     
     
         9 . The method of  claim 8 , comprising steps of:
 adjusting the reciprocal orientation between the rollers of the set of roller units before the step of replacing the set of roller units;   replacing the second set of roller units with the set of roller units after the step of replacing the set of roller units;   wherein between the step of replacing the set of roller units and replacing the second set of roller units the reciprocal orientation between the rollers of the set of roller units is maintained.   
     
     
         10 . The method of  claim 8 , wherein the frame comprises a first upper part which bears idler rollers and/or drive rollers, a second upper part which bears idler rollers and/or drive rollers and a lower part which has the first seats and the second seats, wherein the first upper part and the second upper part are both hinged to the lower part and wherein the interfolding machine comprises at least an actuator which moves the first upper part and the second upper part between a first operating position and a second maintenance position in which the first upper part and the second upper part free the space above the roller units of the set so as to enable the lifting thereof;
 wherein in the step of providing a system further comprises the step of:   activating an actuator so as to bring the first upper part and the second upper part into the second maintenance position before the step of replacing the set of roller units.   
     
     
         11 . An interfolding machine for the production of interfolded packs of sheet articles from strips which comprises a frame and an interfolding unit, for cutting sheet articles from strips and for arranging the sheet articles so as to realise interfolded packs, which comprises a set of roller units, having a first roller unit and a second roller unit the rollers of which are configured for moving sheet articles, and folding elements cooperating with the first roller unit and the second roller unit in order to arrange the sheet articles in an interfolded way, wherein:
 each roller unit of the set comprises a first part, a second part and, between them, a roller which is rotatable with respect to the first part and to the second part about a respective rotation axis;   the first part and the second part of a roller unit of the set are distinct respectively from the first part and from the second part of another roller unit of the set;   the frame comprises, for each roller unit of the set, a first seat which removably houses a respective first part and a second seat which removably houses a respective second part;   the interfolding machine being characterised in that it is configured in such a way as to enable lifting the roller units of the set together.   
     
     
         12 . The interfolding machine of  claim 11 , wherein the frame comprises a first upper part which bears idler rollers and/or drive rollers, a second upper part which bears idler rollers and/or drive rollers and a lower part which has the first seats and the second seats, wherein the first upper part and the second upper part are both hinged to the lower part and wherein the interfolding machine comprises at least an actuator which moves the first upper part and the second upper part between a first operating position and a second maintenance position in which the first upper part and the second upper part free the space above the roller units of the set so as to enable the lifting thereof.