Abstract:
A printing press having a jaw mode assembly and a rotary mode assembly with a single folding cylinder adapted to feed either the jaw mode assembly or the rotary mode assembly is disclosed. A moving web of material is initially trained about the folding cylinder and cut into a signatures which are then temporarily held on the folding cylinder. A folding blade extends from the folding cylinder to initiate a fold in each signature and direct each signature to either the jaw mode assembly or the rotary mode assembly. The timing of the folding blade is coordinated and adjusted using an indexable spider assembly to feed either the jaw mode assembly or the rotary mode assembly.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to printing presses and, more particularly, relates to printing presses adapted to fold signatures cut from a moving web of printed material. 
     BACKGROUND OF THE INVENTION 
     Signatures produced from printing presses, such as those for newspapers, periodicals, and catalogs are typically cut from a moving web of printed material traversed through the printing press. After the cut, the signature is typically folded at least once to produce the desired configuration for the end product. 
     The printing press industry has typically employed one of two mechanisms for creating a fold within a signature cut from a moving web. One of the known mechanisms for creating the fold is referred to as a rotary folder or couple, wherein a pair of second fold rollers are positioned proximate a folding cylinder with a gap or nip being provided between the second fold rollers. The web of material is wrapped around the folding cylinder and a folding blade is adapted to extend from the folding cylinder in a position corresponding to the nip. The folding blade is typically mounted to a spider assembly used to appropriately time the extension of the folding blade. When a folding blade extends from the folding cylinder, the folding blade extends into the nip, pushing the signature cut from the web into the nip. The second fold rollers, which rotate away from the folding cylinder, complete the fold in the signature initiated by the folding blade, and process the folded signature on to a delivery system including such things as delivery flies and conveyor belts. 
     Another known type of folding couple is referred to as a jaw folder wherein a jaw cylinder is positioned proximate the folding cylinder with a plurality of jaws or clamp assemblies positioned around the periphery of the jaw cylinder. The timing of the rotating jaw cylinder is coordinated with the rotation and extension of the folding blade from the folding cylinder such that when the folding blade extends from the folding cylinder, the folding blade extends into one of the jaws or clamp assemblies on the jaw cylinder. This in turn pushes the fold of the signature into the jaw or clamp to complete the fold. The jaw is then released to allow the folded signature to be transported away by a delivery system. Examples of such jaw cylinders are disclosed in U.S. Pat. Nos. 5,226,871, 5,522,586, and 5,797,319, the disclosures of each being herein incorporated by reference. 
     While such systems continue to be used, certain production criteria necessitate the need for one or the other type of folding couple. For example, rotary folders have proven to be extremely rugged and durable and thus are often preferred by facilities wherein it is desirable to produce a large quantity of product on a daily basis, such as with a newspaper. However, jaw folders have proven to be more accurate and to result in minimized marking on the signatures and thus are more desirable in situations wherein extremely high quality and accuracy are at a premium, such as with magazines and catalogs. 
     Some printing presses are equipped with both mechanisms. However, such presses are relatively expensive in that, among other things, two separate folding couples need to be provided. This includes additional frames, drive shafts, drive gearing, delivery flies, and conveyors. In addition, since the hardware for both the rotary folder and jaw folder are provided on the same press, regardless of which is being used, the mechanics of the resulting press are tightly grouped, with little access room being provided in the press for maintenance and the like. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the invention, a printing press folding system is provided which includes a frame, a folding cylinder mounted to the frame, a jaw cylinder mounted to the frame, and a rotary mode assembly mounted to the frame. A moving web of printed material is adapted to traverse through the printing press and be cut into individual signatures. The folding cylinder is adapted to receive the signatures and includes a folding blade adapted to extend radially therefrom to initiate a fold in each signature. The folding cylinder is configurable into a rotary mode or a jaw mode. The jaw cylinder is positioned proximate the folding cylinder and includes a plurality of clamp assemblies extending radially therefrom, each clamp assembly being adapted to receive the folding blade and a folded signature therein when the folding cylinder is in the jaw mode. The rotary mode assembly includes a pair of second fold rollers separated by a nip which is adapted to receive the folding blade and a signature therein when the folding cylinder is in the rotary mode. 
     In accordance with other aspects of the invention, the folding blade may be connected to a timing mechanism which is adjustable to cause a folding blade to extend either into one of the clamp assemblies when in the jaw mode, or into the nip when in the rotary mode. The timing mechanism may include a planetary gear system. 
     In accordance with another aspect of the invention, a folding couple for a printing press is provided which includes a rotary mode assembly, a jaw mode assembly, and means for directing a fold in a signature to either the rotary mode assembly or the jaw mode assembly. 
     In accordance with yet another aspect of the invention, a method of producing folded signatures from a moving web is provided including the steps of cutting the moving web into signatures, creating a fold in the signature, and directing the fold to a rotary mode assembly or a jaw mode assembly wherein the rotary mode assembly and jaw mode assembly are provided on the same folding couple. 
     These and other aspects and features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic representation of a printing press according to the invention configured into a rotary mode; 
     FIG. 2 is a schematic representation of a printing press according to the invention configured into a jaw mode; 
     FIG. 3 is a schematic representation of a printing press according to the invention, depicting a spider motion that is typical in the industry but which is timed in accordance with the invention to cooperate with a rotary mode assembly; 
     FIG. 4 is a side sectional view through a folding cylinder and spider assembly typical of rotary folders currently existing in newspaper printing plants, and used by the invention. 
     FIGS. 5A-G are schematic representations of a printing press according to the invention in sequenced stages of operation in the rotary mode; and 
     FIGS. 6A-G are schematic representations of a printing press according to the invention in sequenced stages of operation in the jaw mode. 
    
    
     While the invention is susceptible to various modifications and alternative constructions, certain illustrative embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions and equivalents falling within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, and with specific reference to FIGS. 1 and 2, a printing press folder according to the present invention is generally depicted by reference numeral  20 . As shown therein, the printing press folder  20  includes a frame  22  relative to which a moving web  24  is adapted to move. While not depicted, it is to be understood that the web  24  is typically provided in the form of a wound roll of paper which is threaded and pulled through the printing press folder  20  to have various printing procedures performed thereon. Once printed, the web  24  is cut into signatures  26  and folded into end units  28 . 
     First with regard to FIG. 1, the rotary mode into which the printing press folder  20  can be configured is shown. The web  24 , moving in the direction of arrow A, is initially wrapped partially around a folding cylinder  30  and held thereto by a first set of pins  32  (FIG.  3 ). As will be described in further detail herein, the first set of pins  32  are timed to extend from the folding cylinder  30  prior to cutting, and retract into the folding cylinder  30  prior to folding. A second set of pins  32  (FIG. 3) is provided to hold the web  24  to the folding cylinder  30  after the signature  26  is cut. A third set of pins  32  (FIG. 3) is also provided so as to allow for continuous operation more fully described below. 
     After the first set of pins  32  have extended from the folding cylinder  30  and into the web  24 , the web  24  is cut into signatures  26  by cutting blades  34  extending radially from a cutting cylinder  36 . In the depicted embodiment, the cutting cylinder  36  rotates counterclockwise (arrow B) and the folding cylinder  30  rotates clockwise (arrow C). The cutting blades  34  cooperate with anvils  38  provided on the folding cylinder  30  to create the signatures  26 . After the cut is made the web  24  continues to be held to the folding cylinder  30  by the second set of pins  32  (See FIG.  3 ). 
     As best shown by FIGS. 5A-G, when the press  20  is in the rotary mode, a fold  40  is created in the signature  26  simultaneously with the cut being made by the extension of one of two sets of folding blades  42  from the folding cylinder  30 . The extension of the first set of folding blades  42  causes the tips  43  of the blades  42  to create the fold  40  (FIG. 5B) and push the fold  40  of the signature  26  into a nip  44  provided between a pair of second fold rollers  46  and  48 . Once the signature  26  is frictionally gripped in the nip  44 , rotation of the first and second fold rollers  46  and  48  in the directions indicated by arrows D and E, respectively, in FIG. 1, causes the signature  26  to be pulled away from the folding cylinder  30 . This motion completes the fold  40  and results in a folded signature or end unit  28 . The first set of pins  32  are retracted in a timely fashion along with the extension of the first set of folding blades  42  to free the signature during folding. 
     Below the folding cylinder  30 , a delivery system  50  is provided. The delivery system  50  includes a delivery fly  52  above an exit conveyor  54 . The delivery fly  52  includes a rotating hub  56  from which a plurality of arcuate vanes  58  extend. Each pair of adjacent arcuate vanes  58  defines a pocket  60  adapted to receive an end unit  28 . Rotation of the delivery fly  52  in the direction indicated by arrow F causes the end unit  28  to be deposited upon the exit conveyor  54  with the folds  40  facing forward for transportation to downstream equipment (not shown) in the direction of arrow G. 
     Referring now to FIG. 2, the printing press folder  20  is shown configured into a jaw mode. It will be noted that the equipment associated with the rotary mode remains positioned proximate the folding cylinder  30 , but that the first and second sets of folding blades  42 , when the printing press folder  20  is in the jaw mode, extend in a different rotational position than in the rotary mode. The timing mechanism to accomplish such a difference in the extension of the sets of folding blades  42  will be discussed in further detail herein. A second timing mechanism is provided to coordinate extension and retraction of the first, second and third sets of pins  32 . 
     FIGS. 6A-G depicts the jaw mode assembly in various stages of operation. As shown therein, a jaw cylinder  62  is provided proximate the folding cylinder  30  and adapted to rotate in the direction of arrow H (see FIG.  2 ). The jaw cylinder  62  includes a plurality of jaw clamps  64  radially extending therefrom. The jaws  64  include first and second clamp arms  66  and  68  which are adapted to close and open to grip folds  40  created in signatures  26 . The rotation of the jaw cylinder  62  is timed such that one of the sets of the folding blades  42  extends and pushes the fold  40  into one of the clamps  64  as both rotate. Further rotation of the jaw cylinder  62 , after a signature  26  has been clamped, completes the fold  40 , resulting in the end unit  28 . 
     The end unit  28  is delivered by the jaw cylinder  62  to a second delivery system  70 . The delivery system  70  includes a delivery fly  72  positioned above an exit conveyor  74 . The delivery fly  72  includes a hub  76  from which a plurality of arcuate vanes  78  extend. Each adjacent pair of arcuate vanes  78  defines a pocket  80  adapted to receive an end unit  28 . Rotation of the delivery fly  72  in the direction indicated by arrow I causes the end units  28  to be deposited upon the exit conveyor  74 , which transports the end units  28  in the direction indicated by arrow J. 
     From FIGS. 1 and 2, it can be seen that using a single folding cylinder  30 , the printing press folder  20  can be configured from a rotary mode to a jaw mode. In the rotary mode, the hardware associated with the jaw mode is not utilized. Similarly, when the printing press  20  is in the jaw mode, the hardware associated with the rotary mode is not utilized. It is important to note that the printing press folder  20  can be purchased and installed with the hardware associated with rotary mode only, the jaw mode only, or both. In any scenario, only a single folding cylinder  30  is needed, thus reducing cost, and enhancing accessibility. 
     The first and second sets of folding blades  42 , as indicated above, can be configured to extend from the folding cylinder  30  at different rotational positions and at various intervals through the use of a timing mechanism  82 . The timing mechanism  82 , referred to as a spider assembly, is adapted to extend the folding blades  42  radially outward, as shown in FIGS. 1 and 2, upon every 120° of rotation of the folding cylinder  30 . 
     With regard to the mechanics of the spider assembly  82 , FIGS. 3 and 4 depict the spider assembly  82  in detail. The spider assembly  82  is preferably a planetary gear system having a drive gear  84  rotating in the same direction as the folding cylinder  30 . The drive gear  84  is motionless with respect to ground, but a drive device  86  rotates about the drive gear  84  in the direction indicated by arrow K. The drive gear  84  includes teeth  88  which mesh with teeth  90  of first and second intermediate gears  92 . The teeth  90  of the intermediate gears  92  mesh with teeth  96  of first and second folding blade shafts  98 , respectively. The first and second sets of folding blades  42  are attached to the first and second folding blade shafts  98 , respectively. Therefore, rotation of the drive gear  84  in the direction of the arrow K causes rotation of the intermediate gears  92  in the same direction, which in turn causes rotation of the folding blade shafts  98  in the opposite direction as indicated by arrow L. 
     Given the respective diameters of the folding cylinder  30 , the drive gear  84 , the intermediate gears  92 , and the folding blade shafts  98 , it can be seen that the folding blade shafts  98  make multiple rotations for each individual rotation of the folding cylinder  30 . This is illustrated by pathways a and a in FIGS. 5A-G and  6 A-G, wherein the pathway designated by a indicates the motion of the folding blade shafts  98  with respect to ground, and the pathway designated by  0  indicates the motion of the folding blade tips  43  with respect to ground. By using first and second sets of folding blades  42  and the gear system described, one of the folding blades  42  extend beyond the periphery  83  (see FIG. 4) of the folding cylinder  30  at the location of the second fold rollers  46  and  48  upon every 1200 of rotation of the folding cylinder  30 . 
     In FIGS.  3  and  5 A-G the extension of the folding blades  42  beyond the periphery  83  of the folding cylinder  30  corresponds to the location of the nip  44 . If, however, the user wishes to switch to jaw mode, the first and second sets of folding blades  42  can be extended radially outward beyond the periphery  83  of the folding cylinder  30  at a position corresponding to the location of the jaw cylinder  62 . This is done by indexing the entire drive device  86  one hundred and twenty degrees clockwise from the position shown in FIGS. 5A-G to the position shown in FIGS. 6A-G to thus coordinate the extension of the folding blade  42  with the location of the jaw cylinder  62 . Such indexing simply requires the drive gear  84 , drive device  86 , intermediate gears  92 , and folding blade shafts  98  to be physically moved. After indexing, each set of folding blades  42  continues to extend radially outward after every 120° of rotation of the folding cylinder  30 , but the folding blades  42  only extend beyond the periphery  83  of the folding cylinder  30  at the location of the jaw cylinder  62 . 
     From the foregoing, it can therefore be seen that the disclosed apparatus and method are able to produce folded signatures from a moving web of material in either a rotary mode or a jaw mode to thus provide the beneficial features of both modes, while minimizing equipment requirements and enhancing physical access space to the press.