In the typography and bookbinding sector, alongside machines for printing and production of the bound product, various devices are known for performing binding operations on publishing products.

In particular, stitching machines are known that use staples or thread, i.e. machines for the binding of publishing products, mainly books, but also pamphlets, brochures and the like.

Stitching machines need loading and feeding with paper (i.e. the printed sheets to be bound), and at present this loading takes place mainly by feeding the stack of sheets to be bound from above. When the pile runs out, the machine must be stopped in order to allow the loading of another stack.

Systems for loading and feeding the stacks of sheets are known in which the feeding of the stitching machine takes place from below. Such systems are described in US2007/0254793 and EP0945377. In these systems, the stack of sheets is in the form of a block, from which the sheets are removed starting from the bottom. The stack of sheets in block form involves a rather complex handling system.

The technical problem addressed by the present invention is therefore that of providing a loading and feeding device for a bookbinding stitching machine that avoids the need for stoppage of the machine during operations of loading successive stacks of sheets. A further technical problem solved by the present invention is that of providing the feed rapidly and without jams.

This problem is solved by means of a loading and feeding device in accordance with the main claim of the present patent application. Preferred embodiments of the invention are also described in the dependent claims.

In the context of the present invention, the term "bound product" means a product formed by a plurality of stacked sheets, joined together along one of their median lines by the application of a binding system, particularly a stapler or a thread stitching machine.

In this regard, as will be fully understood by an expert in the bookbinding sector, "stapler" conventionally means the bookbinding technique that involves the insertion of one or more staples to hold the sheets together; "thread stitching" conventionally means the joining together of the various four-sheet insets that constitute the bound product (generally a book, but also pamphlets, brochures and other publishing products) with the use of a thread (linen, cotton, hemp, synthetic) that passes from the outside to the inside from the back of one signature to the next, holding them together to form the book block.

The device according to the present invention therefore makes it possible to feed a stitching machine, as a stapler or thread stitching machine, in a rapid and reliable manner and without having to stop the machine, thus drawing the maximum benefit from its speed capabilities and obtaining a high overall productivity. In particular, the device according to the present invention allows a particularly rapid feed flow of sheets without jams or backlogs of sheets, and ensures that the sheets flow one by one, without overlaps or multiple sheet feeds.

It is an object of the present invention a loading and feeding device 100 for a bookbinding stitching machine, comprising: a. means 101 for advancing sheets of paper 111, where said sheets are arranged in scaled manner and said means 101 are operated by a first motor 102;

b. downwardly with respect to said means for advancing 101, is provided a housing 105 for said sheets of paper;

c. a suction drum 103, operated by a second motor 104, is located below said housing 105, said drum 103 being capable of picking up said sheets from below; d. a counting system 106 of said sheets is located in said housing 105;

e. one or more advancing drums 109 is or are downwardly located with respect to said housing 105;

f. one or more creasing drums 107 is or are downwardly arranged with respect to said one ore more advancing drums 109;

g. one or more folding belts 108 is or are downwardly arranged with respect to said creasing drums 107.

In a preferred embodiment of said device, said counting system 106 of said sheets is a photoelectric cell.

In another preferred embodiment of said device, a double sheet sensor is located near said suction drum 103.

In another embodiment, said device further comprises a pressing station 110 for folded insets and means for introducing said insets into a stitching machine.

The present invention also concerns a device for binding a publishing product comprising the loading and feeding device described above and a bookbinding stitching machine, for example a stapler or a thread stitching machine.

The characteristics and further advantages of the invention will emerge more clearly from the detailed description of some exemplary embodiments illustrated by way of indicative and non-limitative examples, with reference to the annexed drawings, in which: Figure 1 is a first simplified schematic perspective top view of the present invention, from the paper loading side;

Figure 2 is a second simplified schematic perspective top view of the present invention, from the side of the interface with the stitching machine;

- Figure 3 is a simplified schematic side view of the present invention;

Figure 4 is a simplified schematic perspective top view of the present invention, showing the whole of the loading and feeding system;

Figure 5 shows a detail of the holder 112 equipped with the suction system; Figure 6 is a flow diagram illustrating schematically the functioning of the loading and feeding device illustrated in the preceding drawings.

The drawings show partial embodiments of the device of the present invention, on the understanding that a person averagely skilled in the art will understand the device in its entirety.

With reference initially to Figures 1, 2, 3 and 4, a loading and feeding device 100 of a stitching machine comprises means for advancing 101, operated by a first motor 102. Subsequently, downstream of said means of advancing 101 is provided a suction drum 103, operated by a second motor 104. Said suction drum 103 lies beneath a suitable housing 105 serving as a temporary storage for the paper. In said holder is provided a counting system 106, typically a photoelectric cell. Subsequently, downstream of said housing 105 are provided creasing drums 107, driven by suitable advancing drums 109. Downstream of said creasing drums 107 are provided suitable folding belts 108.

Downstream of said device 100 is provided a suitable pressing station 110 for the folded insets (shown in Figure 2) and means for introducing the insets into the thread stitching machine (not shown in the drawings). Preferably, said means for advancing 101 are in the form either of single belts or double or multiple belts in parallel. These means for advancing may also be provided with a rear holder capable of holding in position the scaled stack of sheets (not shown in the drawings). Said means for advancing are actuated in such a way as to cause the scaled paper to advance along the plane determined by said means 101 and in a longitudinal direction of travel with respect to the axis of said loading and feeding device.

In greater detail, a characteristic element of the present invention is represented in Figure 3, showing the assembly of the housing 105, the suction drum 103, the holder 112 and the counting system 106, for example a photoelectric cell.

The manner of operation of the device according to the present invention is illustrated in Figure 4 in the exemplary embodiment with a thread stitching machine. It is understood that a person skilled in the art can adopt suitable contrivances to use the present invention with any other type of stitching machine, for example a stapler. The previously scaled paper, also shown schematically in Figures 1-3 with the reference 111, is placed upon said means for advancing 101 (Figure 3), which, operated by said first motor 102, cause said scaled paper to advance to said housing 105, creating a stack of sheets (block) in the desired number for the formation of the inset. The desired number of sheets is determined by said counting system 106 (typically a photoelectric cell), which reads the height of said block. Once the desired number of sheets has been reached, the counting system interrupts the advance of the sheets from the scaled stack of paper, by sending a stop command to said first motor 102.

Once said block has been formed, said suction drum 103, operated by said second motor 104, sucks the first bottom sheet of said stack from said housing 105 and sends it through said advancing drums 109, typically two or more in number arranged in opposing pairs. At the moment when the sheet picked up by the suction drum 103 is taken by the advancing drums 109, the suction ceases. Said sheet then passes via said advancing drums 109 to said creasing drums 107, which crease the sheet. Typically, the creasing drums are in pairs, where the upper drum has the female part and the lower the male part. The sheet thus provided with the required creasing passes to said folding belts 108. Typically, the folding belts are two in number, with two lateral coupling belts.

At the moment when said sheet passes from said creasing drums 107 to the folding belts 108, said suction drum 103 picks up another sheet from the block present in said housing 105 and sends it to said advancing drums 109, and thus to said creasing drums 107 and said folding belts.

The cycle continues until the photoelectric cell 106 detects the lowering of the height of said block and then sends a start command to said motor 102, which causes said scaled paper 111 to advance towards said housing 105 to form a next block, as determined by said photoelectric cell 106.

The folded insets arrive at a suitable pressing station 110 (Figure 2) and means for introducing the insets into the thread stitching machine (not shown in Figure 2).

From the description provided thus far, it is evident that at the moment when said scaled stack of paper 111 is close to running out, the operator of the machine can load a next scaled stack of paper, placing it on top of the one that is running out. In this way, the device according to the present invention can continue to feed the stitching machine without having to stop it, unlike the solutions of the known art. This is because, unlike the known machines, the device described herein is characterised by the manner of picking up the sheets from the block from below, leaving the upper surface of the block, and also of the scaled stack of paper, free for successive loadings. It is important to note that the present invention sucks up the sheets in an incremental manner, unlike the known machines, where the sheets are picked up in a decremental manner. This characteristic presents a further advantage. In the event that a double sheet is sucked up, it is not necessary to stop the machine described herein.

This is because the manner of incremental accumulation adopted in the present invention greatly simplifies the work required in the event that said suction drum 103 accidentally picks up a double sheet (as can happen when working with porous paper or special types of paper). The device described herein is suitably provided with a double sheet sensor, which detects the double sheet and corrects the working sequence while continuing to produce without shutting down, unlike the machines currently in existence, which in the event of a double sheet require the machine to be stopped and the two double insets to be reversed. As can be seen in the diagram below, picking the sheets up from below, even if two sheets are picked up, the sequence does not change, unlike in the known art.

STITCHING MACHINE

The invention thus solves the posed problem, and simultaneously provides a number of advantages. In particular, the device according to the present invention makes it possible for the machine, whether a stapler or a thread stitching machine, to be fed in an extremely rapid manner, without having to stop the machine when a new stack of sheets needs to be provided. This advantage is easily obtained by feeding said means for advancing 101 with a succeeding scaled stack of paper before the previous scaled stack of paper runs out.

In a particularly preferred embodiment of the present invention, at the extremity of the plane determined by the means of advancing 101 and at the join between said plane and the housing 105, is provided a holder 112, which has the function of ensuring the alignment of the block of sheets that is being formed in said housing. Said holder 112 is a manifold connected to a vacuum system and is illustrated in particular in Figure 5.

From the scaled stack of sheets 111, the first sheet from the bottom arrives from the plane determined by the means for advancing 101, passes over the upper surface 122 of said holder 112 and falls into the housing 105. Meanwhile, the sheet immediately following the first, again from the bottom of the scaled stack of sheets 111, advances towards the housing 105 to form the block of sheets. As the block is gradually formed, until the counting system 106 determines the quantity of sheets that it contains, the rear wall 124 of said holder 112 ensures the correct vertical alignment. The wall 124 is connected with the lower plane of the housing 105, where the block is formed, with an inclined plane 123, which also ensures the scaling of the block.

Once the counting system 106 has determined the quantity of sheets that make up the scaled block in the housing 105, the suction drum 103 picks up the first sheet from the block from below and sends it towards the creasing and folding system for the formation of the insets.

To ensure the speed of the device according to the invention and the constant flow of the sheets without jams, the holder 122 is provided with one or more holes 125 connected to a vacuum system. Preferably, the holes 125 are sufficient in number (for example 2, 3, 4, 5 or 6) to hold the lower sheet of the block in place on the plane 123. In this way, when the first lower sheet of the block is picked up by the suction drum 103, the immediately next sheet is held in place by the vacuum exerted through the holes 125 made in the plane 123 of the holder 122. As soon as the first sheet has been sent by the suction drum 103 towards the inset creation system, the vacuum through the holes 125 is discontinued, leaving the second sheet free to be picked up by the suction drum 103. As soon as the second sheet is taken up by the suction drum 103, the next sheet from the lower part of the stack (third sheet) is held in place by the vacuum through the holes 125, and so on until the block runs out.

Conveniently, the counting system 106 may also be programmed for a continuous or semi-continuous feeding of the scaled block of paper 111 at the moment when the suction drum 103 has picked up from the block a sufficient quantity of sheets to require a further feeding of the block via the means for advancing 101, without having to wait for the block to run out.

Conveniently, the housing 105 may also comprise a series of blowers 113 provided in the side walls 114 of the housing 105. Said blowers, which may be provided with suitable regulators 115, ensure that the sheets advancing from the lower face of the block are kept separate, thus facilitating their sliding motion.

The present invention also concerns a method for feeding a bookbinding stitching machine comprising the following steps:

a. preparing a scaled stack of sheets to be bound;

b. advancing said scaled stack to a temporary storage position for forming a block of said sheets;

c. performing a count of said block to a predetermined number of sheets;

d. halting the advance of said scaled stack when said number of sheets is reached;

e. picking up from said block a first sheet from the lower side of said block;

f. sending said first sheet to the creasing and folding stages; g. picking up successive sheets from said block from said lower side of said block; h. sending said successive sheets to said creasing and folding stages;

i. collecting said creased and folded sheets in insets to form a signature.

Conveniently, said counting at step c) in said procedure is performed by means of a photoelectric cell.

Conveniently, a double sheet sensor is present at step g) of said procedure.

Conveniently, the loading and feeding device 100 is managed by a software system. Said software system is capable of managing the various components of the device, in particular the system for advancing the first sheet from the lower face of the block when picked up by the suction drum 103 and the system for holding the succeeding sheet by the holder 112, connected to a vacuum system via one or more holes 125.