GB2116151A - Registering book cover subassembly at transverse cutter - Google Patents

Abstract

A web (10) carring spaced boards (22) forming a book cover sub-assembly is provided with indicia, eg slots (20), used to control a cutter during transverse severing of the web. The slots (20) are provided within the marginal regions of the book cover sub-assembly, they are spaced from the longitudinal web edges by more than the width of a margin and have a dimension in the direction of web travel less than two margins. The sub-assembly is formed by accurately glueing wood or carboard boards (22) to a travelling paper, cloth or plastics web using fluidic-or photosensor-controlled sheet and web conveyors for monitoring side notches (18) and centre slots (20) in the web and leading edges (26) of the boards. The central slots (20) are cut through the web simultaneously with the side notches (18). As the sub-assembly approaches a rotating transverse cutter, a photocell and web movement pulse generator are used to control the cutter drive to sever the subassembly (at 12) into separate book cover sections. This arrangement using central slots (20) avoids misalignments occurring with edge indicia, permits observation of the indicia when the longitudinal margins are folded over the boards and avoids machine readjustment when the sub-assembly width is varied. <IMAGE>

Description

SPECIFICATION Registering book cover subassembly at transverse cutter BACKGROUND OF THE INVENTION The present invention relates in general to a new and improved system for bringing a plurality of articles travelling at different speeds in separate paths into registration with each other at a processing station where the paths converge, and in particular to a registration system incorporating means for providing an improved detectable indicium on an elongated flexible sheet whereby said sheet may be brought into a predetermined spatial relationship with a relatively rigid board at the aforesaid processing station. While the invention may find applicability in different areas, it will be explained in connection with a specific manufacturing process.

In the manufacture of book bindings or cases, and the like, a pair of boards consisting of relatively rigid material, such as wood or stiff cardboard, are covered and held together by a flexible material, such as paper, cloth, plastic, or the like. The board and covering material are attached to one another by adhesive.

In high speed case making machinery, the covering material is typically supplied as an elongated web with opposite parallel longitudinal edges in the direction of web travel, the web being notched at predetermined intervals with successive pair of V-shaped notches in opposite edges. The vertices of such pairs of notches lie along a line perpindiuclar to the edges. To this notched web, adhesive and precut boards are then applied in succession.

Subsequent to the application of the board to the adhesive-coated web, the side edges of the web between successive notches are lapped over the adjacent board edges, the web is sectioned along the line between the vertices of opposite notches or each pair, and the remaining edges of the cover are folded over the boards, producing a pair of hingedtogether covered boards. As is well known in the art, the function of the notches is to permit a smooth fold about the corners of the case.

It is important in such an operation that the boards and the covering material are brought together in proper registration, and that this registration is observed in the folding and web cutting operations. Lateral registration between the boards and the web (i.e., alignment normal to the direction of travel but in the respective travel planes of the items) is readily provided by suitable guides or roller flanges which keep the boards and the web in line as they move toward the joining station in their respective paths. However, registration in the direction of travel presents a problem, particu larly at high speeds of operation. Lack of proper registration may lead to an unacceptable end product, the cover material, when cut, not properly covering an edge or corners of the boards.While it is possible to employ large over-lapping folds of the covering material to partially compensate for lack of registration, such a practice is wasteful of the cover material, increases the cost of the end product, and generally provides an unacceptably lumpy case. In any event, poor corner or edge binding and edge margins of different widths are unacceptable in the end product.

A prior art registration system which has been successfully employed in case making has been disclosed in U.S. Patent 4,070,226.

The system there described includes means for conveying the board and the web at different respective speeds along a pair of paths toward a processing station. Each path includes a reference position and means for measuring the distance traveled by each article beyond the corresponding reference position. A comparison of the measured distances traveled by board and web provides an indication of the registration differential. The speed of each article is varied to reduce the registration differential to zero prior to the time the board and web are brought together. Upon registration, the respective travel speeds are equalized so that both articles will arrive at the processing station in unison while maintaining registration with one another. As described in U.S.Patent 4,070,226, the Vshaped edge notches are used as indicia along the web, and photocells are provided at stations along the edge of the web to detect them. As the edges of the V-shaped notches are canted at an angle to the direction of web travel, they are not suitable as precision indicia, since any lateral motion of the web would shift the apparent longitudinal position of the indicia. Thus, the indicia are provided along the length of the web by specially cutting the notches to provide at least one and preferably two indicium, as shown in Fig. 1, in the form of an edge 11 perpendicular to the direction of web travel. It is these edges which are detected by the photocells spaced along the edge of the web.

While such systems are satisfactory, the edge cutting of the web to provide location indicia leads to a number of problems. Thus, for instance, adhesive applied to the web prior to applying the boards differentially wets the web, causing its edges to curl, and thereby introduces a possible timing or alignment error. Further, once the edges of the web have been lapped over the board, the edge indicia are no longer accessible for easy observation.

Consequently, in those case making systems where the longitudinal edges of the web are folded prior to separation of the web into indivdual sheets, accurate synchronization of the cutter requires the use of other indicia and sensing means, often a disadvantage. Thus, sensing indicia printed on the web requires changes in ink and photodetector gain or trigger level for changes in web stock, while sensing the boards attached to the web by mechanical means is difficult when thin board stock is employed. Finally, systems accomodating different width webs commonly convey the web centrally through the system, making it necessary to laterally adjust the notching and cutting mechanisms and the indicia detectors each time the web width is changed.

Accordingly, it is a primary object of the present invention to provide a registration system which is not subject to the foregoing disadvantages. More specifically, it is an object of the present invention to provide a system for registration between a web and other objects which system is not susceptible to alignment errors brought about by curling of the web due to differential wetting of the sides of the web by an adhesive or the like. It is also an object of the present invention to provide a registration system wherein indicia on the web are available for non-contact detection even after the longitudinal edges of the web have been wrapped about the boards bonded to the web, thereby readily accommodating thin board stock.Further, it is an object of the present invention to provide a registration system for centrally fed webs of varying widths in which neither the indicia marking nor sensing devices need be moved each time the web width is changed.

SUMMARY OF THE INVENTION These and other objects are met in the present invention of a registration system having registration or location indicia, preferably in the form of slots, spaced apart along the web in the direction of the web's travel and, in a preferred embodiment, lying substantially midway between the web's longitudinal edges. The long dimension of each slot is made substantially normal to the longitudinal edges of the web. These slots are made to coincide with the lines along which the web will be cut into individual sheets. Both the punch used to form the indicia in the web and the photocells used to observe the slots may be permanently mounted along the center line of the conveyor.

As the center of the web is under tension, differential wetting and swelling of the fibers of the web by an adhesive will not curl the web in the vicinity of the indicia (as occurs with indicia located on the edge of the web).

Finally, after the longitudinal edges of the web between the V-shaped notches have been folded over the adjacent edges of the board, the centrally located slots, disposed between consecutive boards are still available as indicia for synchronizing a cutting blade.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the apparatus possessing the construction, combination of elements, and arrangement of parts and the process involving the steps and the relation and order of one or more of such steps with respect to each of the others, both of which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature and objects of the present invention, reference should be had to the following detailed descriptions taken in connection with the accompanying drawing wherein: Figure 1 illustrates a portion of a case making process using a prior art web provided with edge registration indicia; Figure 2 illustrates a portion of a case making process incorporating the registration process provided by the present invention, as would be used in the process of fabricating a 2-board case; Figure 3 illustrates a preferred embodiment of a case making machine which incorporates the principles of the present invention; and Figure 4 is a fragmentary view of a portion of the notching mechanism of Fig. 3.

In all views, like index numbers refer to like elements.

DETAILED DESCRIPTION OF THE INVEN TION Referring to Fig. 2, there may be seen a portion of a case making process as might be used in the production of a two-board case, as seen from the interior of the unfinished case.

An elongated web 10, which will eventually be divided into successive sheet areas 1 or, lOB, and 1 OC along successive transverse parting lines 12, is propelled by means which will be described in detail hereinafter in the general direction indicated by arrow 14. Web 10, which constitutes the covering material for the case, may consist of paper, cloth, plastic or the like. It is constrained against lateral movement by conventional means, e.g., by suitable guides 16. Alternatively, the rolls used to transport the web along its own path can be provided with flanges to act as guides. As is known in the prior art, successive sheet areas 1 or, 1 or, and 1 OC are defined by the edges of the web and lines running between the vertices of successive pairs of opposed V-shaped edge notches 1 8 spaced along the length of the web. By the present invention, means are provided for also delimiting the successive sheet areas by successive central notches 20 equally spaced along the length of the web. Each notch 20 which serves as a registration indicium is preferably of rectangular shape, with the long axes aligned normal to the longitudinal edges 21 of the web. Aside from notches 20 and notches 18, web 10 is otherwise generally unmarked.

In the fabrication of a case, successive sheet areas 1 OA, 1 OB, and 10C are each provided with corresponding boards 22A, 22B, and 22C. Each board 22 is a precut rectangle of relatively rigid material such as wood or a stiff cardboard. It will be understood that the number of boards 22 provided for each sheet area of web 10 will correspond to the nature of the particular case being manufactured. For the two-board case illustrated for exemplary purposes, each sheet area 10A, lOB, and 10C will be provided with a corresponding pair of boards 22A, 22B, and 22C.As is well known in the art of case making, the sets of boards making up an individual case are spaced apart a sufficient distance to provide for a hinge or spine of covering material therebetween, while successive sets of boards are spaced apart a sufficient distance to permit forming a margin of covering material about the external edges of each case. As will be described in greater detail hereinafter, boards 22 are propelled in the direction indicated by arrow 14 and, prior to being contacted with web 10 are generally aligned therewith by conventional means such as edge guides 24. As with guides 1 6 for web 10, guides 24 for boards 22 may be separately provided guides or may be a portion of the conveying means used to transport the boards to the web.

As will be described in greater detail hereinafter, a principal function of the present invention is to insure proper registration in the direction of travel (indicated by arrow 14) between the leading and trailing edges 26 and 28 respectively of each board 22 and the corresponding parting lines 1 2 of successive sheet areas 1 OA, lOB, and 10C when boards and web meet at station 30, indicated in Fig.

2 by dotted lines. As illustrated by boards 22B and sheet lOB, the boards are longitudinally centered on the sheet when they are in registration. More specifically, the leading edges 26 of each board 22 are spaced from the adjacent parting line 1 2 of the respective sheet by a distance substantially equal to that separating the board's trailing edge 28 from the successive parting line 1 2. It will be understood by those skilled in the art that once boards and web are brought together at station 30, they will be attached to one another by adhesive previously applied to either or both.

Fig. 3 illustrates a preferred embodiment of a case-making machine wherein a board 22C is shown approaching joining station 30 and a previously joined board 22B is shown leaving the station. The path of relatively flexible web 10 may be seen to extend between a web supply roll 32 and joining station 30 as will now be described. Proceeding along the path of travel of web 10, as indicated by arrows 14, the web dispensed by supply roll 32 is threaded past a first guide roll 34, a pair of tensioning rolls 36, and a second guide roll 38.

The web next passes through a notching station 40 adapted to provide the web with the aforementioned central notches 20 and edge notches 1 8. Notching station 40 preferably includes reciprocating pressure plate 41 and cutting blades 42 disposed in opposing relationship to one another and to web 10 such that the web may normally move freely between them. Pressure plate 41 is preferably a flat, hardened plate substantially parallel to web 10 and dimensioned to extend over the area of blades 42. Turning to Fig. 4, there may be seen in greater detail a preferred embodiment of blades 42, as viewed from the plane of web 1 0. Blades 42 are mounted on bar 101, which itself is mounted substantially parallel to web 10 and normal to longitudinal edges 21 thereof.A fixed cutting blade 42A, outlining a rectangle, is situated at the center of bar 101 such that the long dimension of the rectangle is parallel to the length of the bar. A pair of adjustable cutting blades 42B are also provided. Adjustable blades 42B have a V-shaped outline, with the apex of each V directed toward fixed cutting blade 42A. Adjustable cutting blades 42B are movably attached to bar 101, as by collars 102 and set screws 104. Blades 42A and 42B are maintained in alignment with one another as by keyways 106 on bar 101 and keys 108 inside collars 1 02.

Considering once again Fig. 3, pressure plate 41 is intermittently reciprocated through a single cycle, as by drive 43, so as to periodically engage web 10 to blades 42 at predetermined intervals. To this end, drive 43 may be any of a number of well-known intermittently operating mechanical linkages coupling a reciprocating mechanism, such as an eccentric wheel and a cam-follower, to the prime mover of web 10. Alternatively, drive 43 may be an intermittenly operated motor.

The reciprocating linkage between drive 43 and pressure plate 41 (indicated in Fig. 3 as a dotted line connection) is configured to just bring the pressure plate into contact with blades 42 at the end of the plate's travel toward the blades, and to return the pressure plate to a position well clear of the blades and the web at the other extreme of its travel.

Before entering and after leaving notching station 40, web 10 pases over a pair of compensating rolls 44 which support the web through the notching station. Rolls 44 are mounted so as to be reciprocable parallel the direction of motion of the web through the notching station, and, as is indicated by the dotted lines, are also connected to drive 43 by a reciprocating linkage. The linkage between drive 43 and rolls 44 is synchronized with the linkage between the drive and pressure plate 41 so as to move rolls 44 in a direction (as indicated by arrow C) counter to that of web 10 substantially at the velocity of the web during the period the pressure plate is in contact with the web and blades 42, and to move rolls 44 at the web's velocity in the direction of web travel (as indicated by arrow D) during the return stroke (arrow B) of pressure plate 41.

It will be appreciated that other notching mechanisms, such as intermittently counterrotating blades, may also be employed in the realization of the present invention. As is well known in the art, notching station 40 is further provided with means, such as a vacuum purge (not shown), for disposing of the chips resulting from the punching action of blades 42.

The web is next threaded past a third guide roll 45, followed by a glue dispensing station 46. Glue dispensing station 46 comprises well 48, which may be at least partially filled with glue 50, glue applicator roll 52, and glue dispensing roll 54. Glue 50 may be constantly applied to glue dispensing roll 54 by applicator roll 52 which is at least partially submerged in well 48. Glue dispensing roll 54 is adapted to apply glue to the underside of web 10 as the latter comes in contact with the surface of roll 54. As shown, web 10 follows a relatively extended path portion between glue dispensing roll 54 and joining station 30 in order to afford the applied adhesive an opportunity to cure to a state where it becomes tacky. Dancer roll 56 is arranged to provide lateral position control in the aforesaid extended path portion.In rounding dancer roll 56 the under side of web 10, to which the adhesive has been applied, becomes the upper side of the web.

Between dancer roll 56 and joining station 30, the center line of web 10 is observed by fixedly positioned photocell means 58 and 60. Photocell means 58 and 60 are each adapted to provide an output pulse upon detection of each center notch 20 passing by it. To this end, it will be recognized by those skilled in the art that each photocell means 58 and 60 generally would incorporate both a light source and a light detector such that successive notches 20 might either be detected by transmission of light from the source to the detector through a notch, by reflection of light from the source to the detector through a notch, or otherwise. Photocell means 58 and 60 are respectively positioned distal and proximate joining station 30 by a pair of predetermined distances.

Joining station 30 comprises a pair of drive rolls 62 which are faced so as to urge the adhesive carrying web surface against any board 22 that reaches the joining station at the same time. Drive rolls 62, which are mechanically coupled to drive motor 64 (as indicated by a dotted line connection in Fig.

3), constitute the basic drive for transporting web 10 at a selected predetermined speed from supply roll 32 in the direction indicated by arrows 14. In a specific embodiment of the invention, the drive is operated at a constant speed. Drive rolls 62 are further mechanically coupled to a pulse generator 66 which is adapted to provide a train of output pulses at a pulse rate dependent on the rotational speed of rolls 62. Each pulse represents a discrete angular increment of rotation of rolls 62 and hence a unit of distance by which web 10 has advanced in contact with these rolls. Thus, the total number of pulses generated in a given period by pulse generator 66 represents the total distance travelled by the web during that period and this total is independent of the speed at which such distance is covered.

A stack 68 of uniform, flat, relatively rigid boards 22 is supported on base 70, the boards being aligned edgewise along their leading edges 26, as by vertical wall 72. An opening 74 is defined between support 70 and wall 72 and is so dimensioned as to permit a pusher actuator 76 to eject one board 22 at a time from the bottom of stack 68. The pusher mechanism may be of conventional construction and it is preferably of the type responsive to an electrical signal for ejecting successive boards 22 through opening 74 in response to successive actuating signals. Mechanisms of this type are well known in the art and are shown, for example, in U.S. Patent No. 3,814,343. For the sake of clarity and because it is only collaterally related to the present invention, the mechanism has been omitted from the drawing.It will further be recognized, that for the embodiment illustrated in Fig. 2, stack 68 comprises a set of matched stacks spaced apart side by side, with the leading edges 26 of each stack abutting vertical wall 72.

A pair of drive rolls 78, operating at relatively high speed, are positioned in line with opening 74 to move each emerging board 22 rapidly onto a conveyor 80. A photocell means 82 is stationed at a predetermined position adjacent the path of the boards which extends between the stack 68 and joining station 30. It will be understood, that as with photcell means 58 and 60, photocell means 82 incorporates an appropriate light source and detector to sense the respective leading edges 26 of successive boards 22. A pair of variable speed drive rolls 84 are positioned adjacent the path of the board between the position of photo-cell means 82 and joining station 30. Drive rolls 84 are mechanically coupled to a clutch mechanism 86 which may selectively transmit power to these drive rolls either directly at the rotational speed of basic drive rolls 62 or, through suitable bearing included in clutch mechanism 43, at a speed different from that of basic drive rolls 62. In a preferred embodiment of the invention, the differential speed is higher, e.g., by 110%, than the basic speed of drive rolls 62, and be equal to the speed of conveyor 80. However, as will become apparent, other differential velocities between drive rolls 62 and 84 (and conveyor 80) may be employed. It will also be recognized that a separate power source, rather than a clutch mechanism 86, may be used to drive rolls 84.The clutching mechanism required for alternatively clutching rolls 86 to the basic drive or to the high speed drive may comprise conventional two-way clutching apparatus, which has been omitted from the drawings for the sake of clarity. For example, a cone type friction clutch of the type well known in the art may be employed.

Variable speed drive rolls 84 are further mechanically coupled to pulse generator 88 which is adapted to provide a train of output pulses at a pulse rate dependent on the rotational speed of rolls 84. Each pulse represents a discrete angular increment of rotation of rolls 84 and hence a unit of distance by which board 22C has advanced in contact with rolls 84. The total number of pulses generated in a given period represents the total travel of boards 22C during that period, independent of the speed at which the distance was covered. In a preferred embodiment of the invention, the distance units represented by pulse generators 66 and 88 are identical. That is to say, in such an embodiment web 10 advances the same distance for a given number of pulses from pulse generator 66 as boards 22C advance for a similar number of pulses from pulse generator 88.It will be recognized that this condition can be readily met if rolls 62 and 84 are of substantially equal diameters and pulse generators 66 and 88 sense substantially equal increments of angular rotation of the respective rolls.

Beyond joining station 30 a conveyor 90, typically of the known belt type, is provided to transport web 10 and boards 22 B, now jointed together, to the next processing station at the velocity imparted by rolls 62. Typically, the next processing station (not shown) provides means for wrapping the longitudinal edges 21 of web 10 about the adjacent edges of boards 2.

At a subsequent station, the web passes a fixedly positioned photocell 92. Photocell 92 is similar to photocells 58 and 60, and, like them, is positioned along the centerline of web 10. Photocell 92 is adapted to provide an output pulse upon detection of each center notch 20 passing by it. A predetermined distance beyond photocell 92, web 10 passes through cutting station 94. Cutting station 94 preferably includes a pair of counterotating rolls 95 and 96 disposed on opposite faces of web 10. Roll 95 is a rigid cylindrical roll and is continuously driven, as by a mechanical linkage (not shown) to drive motor 64. Roll 95 supports and propels web 10 through the cutting station. Roll 96, disposed clear of web 10, is provided with a blade 98, and is synchronously driven intermittently by drive 100.Blade 98 is disposed so as to engage roll 95 through web 10, thereby cutting the web along a line normal to longitudinal edge 21. Drive 100 is any of a number of mechanical drives which can be cycled on receipt of an electrical signal so as to rotate roll 96 and the attached blade 98 a single time so as to engage the blade to the web and to roll 95 a predetermined time after receipt of the signal, with the blade and web travelling in the same direction and at the same velocity while in contact. For example, drive 100 may be a mechanical linkage including a vacuum actuating clutch or the like coupled to motor 64.

Beyond cutting station 94, the individual cases formed by dividing web 10 into individual sheets, each with an attached compliment of boards 22, are conveyed to subsequent processing stations (not shown) where the case is finished.

In operation, web 10 is unrolled from supply roll 32 at a speed determined by drive rolls 62. As the web passes punching station 40, drive 43 is periodically actuated, each time reciprocating pressure plate 41 through a single cycle alternatively toward and away from web 10 and blades 42 (as indicated by arrows A and B respectively), while simultaneously reciprocating both rolls 44 through one cycle opposite and toward the direction of web travel (as indicated by arrows C and D respectively). On each cycle, pressure plate 41 engages blades 42 through the web, cutting the web to form a set of edge notches 1 8 (punched out of the longitudinal edges 21 of the web by blades 42B) and the corresponding central notch 20 (punched by blades 42A).The translation of rolls 44 during the period of impact between pressure plate 41 and the web is made to be substantially equal and opposite the web's velocity by the reciprocating linkage between rolls 44 and drive 43, thereby momentarily halting the web opposite the notching station. It will be understood that webs of different widths may be accommodated by axially adjusting blades 42B along the length of bar 101. The spacing between successive sets of notches 1 8 and 20 depends on the velocity of web 10 and the timing of drive 43.

As a notch 20 passes photocell 58, it is detected by the photocell. The resulting photosignal may be processed, by means well known, and used to provide an actuating signal to pusher actuator 76. Actuation of pusher actuator 76 causes the bottom board 22 of stack 68 to be ejected through opening 74 in fixed temporal relationship to the passage of a notch 20 past photocell 58. As soon as the board reaches drive rolls 78, it is siezed and moved forward at high speed onto conveyor 80.

When the aforesaid notch 20, having passed photocell 58, reaches photocell 60, it is again sensed. The distance notch 20 has travelled past photocell 60 may be directly determined by mounting pulses of pulse generator 66 after the notch is sensed. Similarly, as each board 22 comes opposite photocell 82, the board's leading edge 26 is sensed.

Variable speed rolls 84 are set in high-speed operation, matching the linear velocity of conveyor 80. Accordingly, the position of leading edge 26 relative to photocell 82 may be directly determined by counting pulses of pulse generator 88 after the edge is sensed.

The relative locations of photocells 60 and 82 and the counts from pulse generators 66 and 88 after passage of the respective notch 20 and leading edge 26 past the photocells thus provide a measure of the distance between notch and leading edge and joining station 30.

In the preferred embodiment, the board dispenser (pusher actuator 76, high speed rolls 78, and conveyor 80) are disposed such that, despite their higher speed, the boards reach photocell 82 lagging their respective sheets 1 OA, lOB, and 10C. The count from pulse generator 66 thus typically starts first.

However, board 22 is approaching joining station 30 at a higher velocity than the web, and the pulse rate from pulse generator 88 is accordingly higher than that from pulse generator 66. Consequently, the difference in count from the two pulse generators is changing.

Registration between board leading edge 26 and notch 20 (i.e., spacing the leading edge a predetermined distance from the notch) is sensed when the count difference from the two pulse generators reaches a predetermined difference. At this point, clutch mechanism 43 is actuated, coupling variable speed rolls 84 to drive rolls 62 such that both sets of rolls feed at the same rate.

The mechanism so far described is, with the exception of notching station 40 and the central location of photocells 58, 60, and 92, substantially the same in structure and function as that described in U.S. Patent 4,070,226, to which reference may be had for further details of the apparatus, a signal processor for use therewith, and its operation.

The primary distinction between the present invention and U.S. Patent 4,070,226 is in provision of means to establish the indicia along the centerline of the web, rather than at one or both edges, and the disposition correspondingly of tbe detectors in central loca tio s froXhich they need not be moved to accommodate for varying web widths.

After departing joining station 30, web 10 and attached boards 22 are conveyed by belt conveyor 90 to subsequent processing stations at the same velocity as that imparted to the web by drive rolls 62. As assembled web and boards approach cutting station 94, they pass beneath photocell 92, positioned a known distance in advance of the cutting station. Photocell 92 detects each notch 20 passing it. The photosignal resulting from the passage of a given notch 20 may be used to initiate a count of pulses generated by pulse generator 66. The position of the notch relative to photocell 92 may be directly determined from this count, the notch passing through cutting station 94 a fixed number of counts after passing the photocell, the exact number depending on the pulse generator and the spacing between photocell and cutting station.Thus, the signal from photocell 92 taken together with the pulses from pulse generator 66 may be used, by well known means, to provide a signal actuating drive 100 so as to drive roll 96 through a single revolution, engaging blade 98 with roll 95 through web 10 just as notch 20 arrives opposite the blade.

Notches 20 are thus made to coincide with parting lines 1 2 along which web 10 is divided into individual sheets. It should be noted that, after cutting, the margins of the individual sheets 1 OA, 1 or, and 10C extending beyond the respective boards 22A, 22B, and 22C are folded over the boards, completing each case. This folding operation will bring parting lines 1 2 over the adjacent leading and trailing edges 26 and 28 respectively of the boards. For the two-board cases illustrated in Fig. 2, the severed half-notches formed from notches 20 when web 10 is cut into individual sheets will then be on the inside of the spine of the case, and thus concealed when the case is affixed to a book.

It should be noted that the invention is not restricted to two-board cases, even though for cases having different numbers of boards, notches 20 might be in line with a board. In this regard, it will be appreciated that the interiors of cases are generally finished-off, as with end papers, and such finishing in part covers the folded-over cover material. Consequently, even in such cases, a centrally disposed notch will be concealed. The only requirement for insuring such concealment, assuming proper registration, is that the maximum width (i.e., the dimension in the direction of travel of web 10) of a severed notch 20 not exceed the width of the fold. For a centrally cut notch 20, this severed notch width corresponds to the half-width of the notch, while for a leading- or trailing- edge cut notch, this width is the overall width of the notch. It should also be noted that, should web 10 be trimed flush with the leading and trailing edges of boards 22, notch 20 may be dimensioned to extend between successive boards.

Since both notching station 40 and photocells 58, 60, and 92 are mounted along the centerline of the web conveyor, and since webs of different widths are generally centrally fed, neither the notching station nor the photocells need be moved when covering differently sized cases. As the center of the web is under tension, differential wetting and swelling of the fibers of the web by an adhesive will not curl the web in the vicinity of notches 20 as it will in the case of edge notches 1 8. Consequently, notches 20 provide more trustworthy indicia than do indicia 11 on edge notches 18 (Fig. 1).Finally, the centrally located notches 20 disposed between consecutive boards 22 are still available as indicia for synchronizing such machine operations as cutting the web into sheets even after longitudinal edges 21 of the web have been folded over the adjacent edges of boards 22.

It will be appreciated that the invention so far described may be modified without departing from the principles of the invention. Thus, while described in terms of the manufacture of two-board cases, it clearly is applicable to the manufacture of cases having any number of boards. It will also be recognized that while V-shaped edge notches 1 8 are preferred for covereing thin boards with thin cover stock, differently shaped edge notches, and indeed a lack of edge notches, may be preferred for certain applications. Thus, as is well known in the art, more complicated edge notching is sometimes of advantage for cases made using thick boards or thick cover stock, while for laminating applications, where the cover stock is commonly trimmed to the board dimensions rather than being folded over the boards, edge notches need not be provided.

While the preferred embodiment incorporates rectangular notches 20, primarily to accommodate slight transver wandering of the web, other configurations of notch are also possible. Thus, for instance, notches 20 might be in the form of a short line of perforations.

Then, too, notches 20 might be replaced by circular apertures and photocells 58 and 60 be provided with rectangular or slit-like fields of view aligned normal to the direction of web travel. It will also be understood that notches 20 (and corresponding blade 42A and photocells 58, 60 and -92) need not be positioned at the web (and conveyor) centerline, but may be disposed at any location intermediate and well clear of longitudinal edges 21 of the web. Such a location, displaced from the centerline, may still be fixed yet accommodate all but the narrowest webs, and would be of particular advantage in the manufacture of exposed-hinge cases (i.e. cases wherein the boards are supplied with a hinge independent of the covering material, and wherein the web is slit prior to joining station 30, so that only the boards, and not the hinge, are covered).

Other forms of indicia (e.g. printed, magnetic, florescent or similar marks) may be employed in place or notches 20, appropriate detectors being substitued for photocells 58, 60 and 92.

Then, too, it will be realized that while the preferred embodiment described in detail hereinabove makes use of photocells for detectors, other detector means (e.g. fluidic sensors), may be used.

Claims (5)

1. An apparatus for use in manufacturing cases, comprising means for applying rectangular boards to an elongated, moving paralleledged web at registered positions spaced longitudinally along the web in the direction of web travel, means for cutting the web into sheets providing a margin about the board, thereby forming a case sub-assembly, means for applying indicia to the web intermediate the longitudinal edges of the web, the indicia being disposed in a pattern having a spacing in the direction of travel of the web greater than the corresponding dimension of a finished case by an amount sufficient to provide for a pair of the margins, the indicia being spaced from the edges of the web by more than the width of a margin, and each of the indica having a width in the direction of travel less than a pair of margins, means fixedly positioned opposite the web and intermediate the parallel edges thereof for detecting the indicia and for providing control signals responsively to the detecting and means responsive to predetermined ones of the control signals for selecting the registered positions.

2. An apparatus as claimed in claim 1, in which the indicia are apertures in the web means being responsive to others of the control signals for cutting the web into substantially rectangular sheets, each cut being made through an aperture and normal to and between opposite longitudinal edges of the web.

3. A registration method for use in manufacturing cases in which rectangular boards are applied to an elongated moving web at selected positions on the web, the web being cut into sheets providing a margin about the boards, thereby forming a case sub-assembly, comprising the sequential steps of applying indicia to the web intermediate opposite longitudinal edges thereof, the indicia being disposed in a pattern having a spacing in the direction of travel of the web greater than a corresponding dimension of a finished case by an amount sufficient to provide for a pair of margins, each of the indicia having a with in the direction of travel less than a pair of margins, applying the boards to the web substantially orthogonally to and equidistant from the longitudinal edges of the web and between and equidistant from adjacent pairs of indicia and cutting the web into substantially rectangular sheets, each cut being made normal to the longitudinal edges of the web.

4. An apparatus for use in manufacturing cases constructed and arranged to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.

5. A registration method for use in manufacturing cases substantially as herein described.