Book sewing machine with automatic separation of books

The present invention relates to a book sewing machine of the type equipped with an automatic mechanism for separating the books which have already been sewn, which includes:

• - a separator element arranged to be inserted between two contiguous books located close to the zone of discharge of the books which have been sewn, and arranged to be displaced in a vertical transverse plane relative to the direction of advance of the conveyor carrying a horizontal pile of the said books towards the said discharge zone from one side to the other of the said pile, and
• - control system including:

  • a marker device arranged to overlie onto the final signature of each book which is at the sewing zone, and an indicator element, so as to separate a part of the said book from the next one.

In a machine of this type, known through the German Patent No. 612,818 the indicator elements have the form of cylindrical rods the length of which is greater than the height of the books. They are inserted between the end of one book and the beginning of the next one for the sake of forming clearances or spaces the presence of which renders the separation of the last book from the horizontal pile easy. The said rods, which may start the operations which must be performed in order to carry out the said separation, follow a closed path and are inserted automatically close behind the sewing zone under the action of a counter capable also of starting the operations of separation of the last book from the horizontal pile and of cutting the stitches connecting said last book to the next one.

The counter, the conveyor means which provide to displace the rods along a closed path, and also the tools cutting the thread stitches are all actuated by mechanisms connected to the main drive of the sewing machine.

In another book sewing machine, known through the German patent No. 582,200 the books of the horizontal pile which is displaced towards the zone of discharge of the books which have been sewn are spaced therebetween by means of an elongated wooden bar of rectangular cross-section, inserted by hand and provided at their upper faces with longitudinal guide-grooves. Such bars meet at a certain point of their travel towards the discharge zone noose-shaped elements and move the latter, thereby temporarily connecting the mechanism controlling the cutters with the main drive of the sewing machine.

In both cases mentioned above cumbersome guides for the bar ends must be provided beyond the opposite longitudinal sides of the machine, and the drive of the latter must be equipped with rather complex mechanisms for controlling the displacements of the said bars and/or those of the cutters, which latter are no less involute and cumbersome.

Thence it will be obvious that the use of the prior art's teachings would not lead to an easy and not expensive modification of a conventional book sewing machine not provided with an automatic mechanism for separating the books which have already been sewn into a book sewing which is equipped with said mechanism. Furthermore the use of long and relatively heavy bars or rods, possible with obsolete book sewing machines running at the speeds of 60-70 strokes/min., can in no case be envisaged with modern book sewers running at speeds which exceed 150 strokes/min.

The object of the present invention is therefore, in general, to eliminate the above said disadvantages and limitations and the invention tackles the problem of simplifying the structure of the book sewing machines equipped with an automatic mechanism for separating the books which have already been sewn, of rendering them less cumbersome and adapted to operate at high speeds, thereby rendering it possible to modify easily book sewing machines deprived of an automatic mechanism for separating books which have already been sewn into book sewing machines equipped with said mechanism.

According to the present invention the problem indicated above is solved by providing a book sewing machine of the type equipped with an automatic mechanism for separating the books which have already been sewn, which includes:

• a) indicator elements capable of separating a part of each book from the next one,
• b) a marker device arranged to overlie onto the final signature of each book which is at the sewing zone one of the said indicator elements,
• c) a separator element arranged to be inserted between two contiguous books located close to the zone of discharge of the books which have been sewn, and arranged to be displaced in a vertical transverse plane relative to the direction of advance of the conveyor carrying a horizontal pile of the said books towards the said discharge zone from one side to the other of the said pile, and
• d) indicator detecting means for actuating the separator element;
  
  

  characterised in that:

• e) that said indicator elements have, at least in part, the form of plates of preferably rectangular shape which are small in relation to the length of the books, and that
• f) said marker device is arranged at one side only of the conveyor carrying the horizontal pile of books, comprises a loader adapted to contain a plurality of said indicator elements and comprises also means adapted to release from the said loader of one indicator element at the end of the completion of one book;
• g) the said marker device being so arranged and shaped, that each indicator element leaving the loader is overlaid on the final signature of each book already sewn close to the upper vertex of the said signature, lying at the side of the conveyor carrying the horizontal pile of the books at which said marker device is arranged, and that said indicator element partially protrudes beyond one of the sides of the said final signature which crosses at the above mentioned vertex.

According to the preferred embodiment, the separator member is in the form of an elongate element inclined to the horizontal plane in which the backs of the books carried by the conveyor lie, so that its lower end is closer to the pile of books is a small distance from the upper corresponding corner of the pile itself; the element being slidable axially downwardly and fixed to the movable element of a linear motor movable towards the opposite side of the pile of books under the action of a second linear motor; the operating cycle of the motors being started by the pulse which the sensor emits on passage therepast of one of the indicators inserted between the contiguous books.

This elongate element may also be constituted by a simple rod or the like intended to fu Ifill solely the function of separating the books by the unstitching of portions of the threads already cut which connect them.

Alternatively the elongate element may be shaped in the form of a cutting blade and the sewing machine which in this case does not have a conventional cutter may conveniently be provided with a glue spreader of known type arranged to apply a layer of glue to the backs of the sewn books which is then cut during separation of the books by the cutting blade. This system is particularly advantageous in that it gives the books which leave the sewing machine a stability of form which is adequate to allow them to be sent directly to the trilateral paper cutter, allowing the back gluerto be omitted from the production line.

The books which leave the sewing machine are also without the threads which normally project from opposite longitudinal sides of the respective backs.

Other characteristics and advantages of the invention will become apparent from the following description with reference to the appended drawings which show, purely schematically, a practical embodiment, and in which:

• Figure 1 is a partial plan schematic view of a book sewing machine according to the invention,
• Figures 2 and 3 are sections taken on lines II-II and III-III of Figure 1,
• Figure 4 is an exploded perspective view showing a construction detail,
• Figure 5 is a schematic partial perspective view showing a constructional variant of the book sewing machine of the invention,
• Figure 6 is a perspective view showing, on an enlarged scale, the marker device of the sewing machine illustrated in Figure 5,
• Figure 7 is an exploded perspective view showing a constructional detail of the sewing machine of Figures 5 and 6, and
• Figures 8, 9 and 10 are schematic side elevational views of some parts of the marker device, showing the positions adopted thereby during a sequence of three successive stages of operation of the device.

In all the drawings, those elements which correspond to each other are indicated by the same reference numerals.

In the drawings (see Figure 1) the movable saddle of the sewing machine is indicated 1 and a signature arriving at this saddle is indicated 2. The broken line 3 shows the zone of sewing or the plane in correspondence with which groups of tools (not illustrated) which effect the sewing operate, and towards which the top of the saddle carrying the signature 2 is brought to carry the signature 2 close to the rearmost signature 4 of the last of the books already sewn. This book, indicated 5, is carried, together with the previously sewn books, by an horizontal conveyor 6 (see Figures 2 and 3) which moves them towards a discharge zone 7.

On one side of the pile of books already sewn carried bytheconveyor6 is the marker device. This includesa a loader shaped in the form of an elongate container 8 of rectangular cross section. It carries within it a plurality of indicator elements shaped in the form of rectangular plates 9 made of any material. These plates are constantly thrust towards the open end of the container 8 which is located a small distance from the said plane 3, by the action of a spring 10 which bears against a removable wall 11 which closes the other end of the container itself.

The marker device also includes an inserter member shaped in the form of a slider 12 which partly closes the open end of the container 8 and which has a vertical base wall 13 (see Figure 4) from the face whereof facing the open end of the container 8 there project a peripheral lower rib 14 and a peripheral lateral rib 15. The upper face of the rib 14 is aligned with the base 16 of the container 8 and the face of the lateral rib 15 facing the pile of books carried by the conveyor 6 is aligned with the inner face of the side wall 17 of the loader. The slider 12 is connected to the shaft 18 of the double-acting pneumatic actuator 19fed through a distributor, schematically shown by the small box 20, controlled by a circuit, also shown schematically by the box 21.

At the end of the formation of each book, that is, in the position illustrated in Figure 1, the circuit 21 - which is arranged so as to come into action at the end of each series of oscillations of the movable saddle necessary for the formation of a book - causes the actuation of the pneumatic actuator 19 through the distributor 20. This latter then makes the respective piston (not illustrated) fixed to the shaft 18 carrying the slider 12 effect a movement towards the pile of books carried by the conveyor 6 (up to the position indicated in broken outline in Figure 1), followed by a return stroke to the starting position illustrated in Figures 1 and 4. This cycle of movements of the slider 12 serves to overlay the indicator held against the base wall 13 and the peripheral ribs 14 and 15 of this wall of the slider on the face of the rear signature 4 of the last book 5 facing the sewing zone 3.

The assembly constituted by the container 8 and the slider 12 cooperating therewith is located at a height such that the plate 9 moved towards the pile of books overlies the part of the signature 4 close to the intersection of its back and its side edge facing the container 8. The base wall 13 of the slider 12 only partly closes the open end of the container 8 and effects a stroke which has a length equal to a fraction of the length of the plate 9 consequently the plate 9' located over the rear signature 4 of the book 5 projects partially from the side of this book facing the container 8. The position and size of the parts are also such that the upper edge of the plate 9' is located, after its superposition on the signature, at the level of the back of the signature 4. The parts of the backs of the contiguous signatures of the successive books located on the sides of these latter facing the container 8 will thus be spaced apart from each other by a small distance equal to thickness of the plates 9' located therebetween.

At a certain distance from the transverse vertical plane in which the slider 12 slides is a glue spreader 22 of known type, for example a "NORDSON" type arranged to apply a layer of glue to the backs of the books which advance on the conveyor 6 towards the discharge zone 7. This gluer is naturally adjustable so as to adapt it to the requirements of the production of sewn books of different heights.

In the discharge zone 7, at a certain distance from the transverse stop plate 23 for the pile of books brought by the conveyor 6 is the separator mechanism. It includes a blade 24 which lies in a transverse vertical plane spaced from the stop 23 by a distance corresponding to the thickness of a book. The blade is inclined to the horizontal plane touching the backs of the books brought by the conveyor 6 at an angle of about 45° and is located so that its lower end is closer to the side of the pile of books facing the container 8 than its other end, and is located, close to the upper corner of the corresponding side of the pile, substantially above the plate 9' inserted between the rear signature of one book and the first signature of the successive book.

The upper end of the blade 24 is fixed to the shaft of a double-acting actuator 25 constituting a replaceable "head" mounted on a horizontal transverse rod 26 which extends beyond the other side of the pile of books and is located at a distance from the stop 23 equal to the thickness of a book. Its end opposite the "head" is fixed to the shaft 27 of another double-acting pneumatic actuator 28 displaced upwardly and towards the sewing zone 3 relative to the rod 26.

Beneath the path traversed by the plate 9' inserted between successive books is a photocell 29 the axis of which lies in the transverse plane containing the axis of the rod 26 whereby, when the plate 9' superimposed on the final signature of the book, the first signature of which has reached the stop 23 lies in this plane, the photocell emits a pulse which is transmitted to a circuit 30 which controls the operation of distributors (not illustrated) which control the operation of the pneumatic actuators 25 and 28 so as to cause the component members of the separator to carry out a working cycle:

• - an axial downward movement of the blade 24 and its penetration between the signatures between which the plate 9', which is lowered, is located;
• - a successive movement of the "head", due to the operation of the actuator 28 which moves the rod 26 by a distance sufficient to bring the blade 24 from the other side of the horizontal pile of the books;
• - the return of the pistons (not illustrated) of the actuators 28 and 25 to the starting conditions, which makes the parts resume the position illustrated in Figure 2.

The first phase of this operation causes the cutting of the layer of glue applied to the backs of the books by the gluer 22 and the cutting of the threads connecting the rear signature of the last book to the first signature of the successive book, thus effecting the separation of the final book.

With the system described above, and with small and relatively inexpensive modifications to conventional sewing machines, one can thus produce books without empty stitches, free from threads projecting from the opposite longitudinal sides of the respective backs, firmly held together by the glueing of these latter and hence ready to pass directly to the trilateral paper cutting machine.

In the embodiment of Figures 5 to 10, each of the plate 9 constituting the indicator elements projects from the middle of the lower face of a small parallelepiped shaped block 31 having a square cross-section.

These blocks 31 carrying the plates 9 are made to leave the lower end of a shaped loader 32 one at a time, the loader being located in a position such that each of the plates 9 can overlie the last signature of a book which has already been formed and such that the lower face of the parallelepiped-shaped block 31 from which the plate 9 projects is at the level of the plane in which lie the backs of the signatures in the horizontal pile advancing towards the stop plate 23.

The loader 32 is constituted by two elongate channel-shaped members 33 facing each other. In the lower, vertically-extending end portion 34 of the loader 32 is located the device 35 for controlling the exit of the indicator elements 9, 31 and their location between the successive books formed by the sewing machine. The block 31 of the indicator element 36 (see Figure 6) located at the bottom of the pile in the loader 32 rests on the fork 37 carried by the device 35.

The fork 37, whose assembly in the device 35 and the system for the control of which by the double-acting pneumatic cylinder 38 are clear from the drawings, particularly Figure 6, may be withdrawn in the direction of the arrow 39 when a signature counter (not illustrated) emits a signal indicating that the formation of a book has been completed.

The movement of the fork 37 in the direction mentioned above is accompanied by the movement of the upper fork 40 in the opposite direction, from the position illustrated in Figures 6 and 8 to the position illustrated in- Figure 9 in which it is beneath the block 31 of the indicator element 41 located immediately above the element 36. This latter, no longer supported by the fork 37, falls under gravity in the direction of the arrow 42 (see Figure 9), while the fork 40 prevents the indicator element 41 from descending.

The lower, vertical end portion 34 of the loader 32 is located in a position such as to ensure that the plate 9 of the indicator element 36 overlies that surface of the last signature 4 (see Figure 5) of the book just formed which faces the sewing zone, in correspondence with that part of this surface closest to the end portion of the respective back which faces the side of the horizontal pile of books in correspondence with which the loader 32 is located.

The upper side part of the first signature of the subsequent book is superimposed immediately on the plate 9 of the indicator element 36 in contact with the last signature of the last book formed so as to prevent it falling downwardly or to the side. The pneumatic actuator 38 - under the action of control members (not illustrated) which have been activated by the signature counter - will finally return the forks 37 and 40 to the starting position. This will occur as a result of the passage of the various parts from the position illustrated in Figure 9 to that illustrated in Figure 10, the movement of all the indicator elements in the loader 32 downwardly by one step, and the stoppage of the element 41 against the fork 37.

The structure further includes an endless chain 43 (see -Figures 5, 6 and 7) located in a plane parallel to the stop plate 23. This passes over sprockets 44 mounted on spindles parallel to the direction of advance of the pile, at least one of which is driven by a motor (not illustrated). These spindles are located so that the path of the chain has two horizontal passes, one 45 of which is disposed close to the plane in which lie the backs of the signatures in the pile which advances towards the stop plate 23 and the other 46 of which is located at such a level as to be above the upper end of the loader 32. In their turn, the lateral vertical passes are located outside the opposite longitudinal sides of the said pile.

The chain 43 (see Figure 7) carries a plurality of small guide and support carriages 47 rotatably mounted about horizontal pins 48 disposed at regular intervals and all projecting from the same side of the chain 43. Each of these carriages 47 has a lower projection 49 carrying a small rod 50 which can penetrate the through hole 51 formed in the blocks 31 of the indicator elements 9, 31. The resiliently expansible heads 52 of the rods 51 necessitate the use of a certain amount of force to disengage the rods from the holes 51.

The wheels 53 of the carriages 47 cooperate with horizontal and vertical guides 54, 55 and 56 respectively, in order to ensure that the carriages 47 and particularly the rods 50 are always horizontal.

The system further includes a sensor constituted by a microswitch or proximity switch (not illustrated) for outputting a signal when the axis of the through hole 51 formed in the block 31 of one of the indicator elements is in the vertical plane containing the axes of the rods 50.

This event occurs during a stoppage of the pile for sewing thereto of a new signature. The signal output by the sensor activates, through a suitable circuit (not illustrated), the motor which drives the chain 43 and the latter advances in the direction of the arrow 57. During this advance, the rod 50, 52 carried by the projection 49 of that carriage 47 waiting close to the corresponding side of the pile penetrates the hole 51 in the element (generally indicated 58 in Figure 5) and moves this element to the position occupied by the element indicated 59 also in Figure 5.

During this movement, the plate 9 of the element 59 cuts the stitches joining two adjacent books in the plane in which the plate moves, and may also cut the layer of glue whenever the latter has already been applied to the backs of the signatures in the pile by a device similar to that indicated 22 in Figures 1 and 3 of the drawings.

At the end of the movement of the chain, the intermittent advance of the pile of books towards the stop plate 23 is resumed, and the position 159 occupied previously by a carriage 47 is occupied by the subsequent carriage shown above and to the right in Figure 5.

In this drawing, the latter is shown in a position just after its disengagement from the indicator element 60, which is stopped by the vertical plate 61 perpendicular to the plane in which the chain 43 lies and provided with a through slot 62 of a width such as to allow the passage of the lower projections 49 of the carriages 47 but not the blocks 31 of the indicator elements. Immediately it is disengaged from the carriage carried by the chain, the element 60 falls into the shaped loader 32 to be added to the top of the pile of indicator elements in the loader.

Naturally, the principle of the invention remaining the same, details may be varied widely with respect to those described above and illustrated in the appended drawings without thereby departing from the scope of the present invention.

Thus, for example, the cutting and separation device could be constituted by a blade movable like a guillotine, that is, in the vertical sense, having its respective cutting edge inclined downwardly towards the side of the pile facing the loader.

The blade 24 could also be replaced by a rod or the like adapted for separating by unstitching. In this case, the sewing machine would still be provided with a normal thread cutter but would be without the spreader for spreading glue onto the respective backs. The overall production line would retain the glueing machine and the advantages achieved would only be those inherent in the elimination of the manual operations of separation and unstitching.

The zone at which the separation is carried out and that in which the photocell for enabling the operation of the separator is disposed could be displaced relative to that illustrated in Figure 1, as long as it was at a distance from the stop 23 equal to a multiple of the thickness of the books carried by the conveyor 6.