Abstract:
Provided is a sheet diverter for directing signatures moving in serial fashion along a diverter path to one of a plurality of collation paths. The sheet diverter includes a pair of diverter rolls for directing a signature to one of the plurality of collation paths and a diverter wedge for deflecting the signature to a selected one thereof. The diverter wedge is positioned between the diverter rolls so as to reach high into the diverter path thereby providing increased support to the signature as it travels from between the diverter rolls to the diverter wedge. The diverter rolls are permitted to intermesh with the diverter wedge so as to allow the diverter wedge to be so positioned.

Description:
FIELD OF THE INVENTION 
     The present invention relates, generally, to sheet diverters for directing sheets moving in serial fashion along a path to one of a plurality of collation paths and, more particularly, to a high speed sheet diverter of the foregoing kind for collation of printed signatures to be used in the binding of a publication such as a magazine or a newspaper. The present invention further relates to an improved diverter assembly for collating sheets, such as signatures, from a high speed printing press. Specifically, the present invention provides a sheet diverter with diverter rolls and a diverter wedge positioned therebetween, the function of which is to allow for faster operating machine speeds with fewer jams and, at the same time, to improve the collation process such that the quality of signatures is improved as the signatures move along one of a plurality of collation paths. 
     BACKGROUND OF THE INVENTION 
     Sheet diverters may range from the collating apparatus associated with an office copier, to sheet or web handling devices employed in the manufacture of paperboard articles, to sheet diverters specifically adapted to collate signatures to be used in binding or otherwise assembling books, magazines or newspapers. Each of these environments presents a somewhat different challenge in designing an efficient diverter or collator, but the same objective applies to the entire class of apparatus, namely, accurately routing selected flexible webs or ribbon sections along a desired collating path to achieve a desired order. 
     In the printing industry, an image is repeatedly printed on a continuous web or substrate such as paper. The ink is dried by running the web through curing ovens. In a typical printing process, the continuous web is subsequently slit (in the longitudinal direction which is the direction of web movement) to produce a plurality of continuous ribbons. The ribbons are aligned one on top of the other, folded longitudinally, and then cut laterally to produce a plurality of multi-paged, approximately page length web segments, termed signatures. A signature can also be one printed sheet of paper that has or has not been folded. It is often desirable to transport successive signatures in different directions or paths. In general, a sheet diverter operates to route a signature along a desired one of a plurality of paths. 
     A sheet diverter in a folder towards the end of a printing press line must be operable at the high speeds of the press line, typically in excess of 2,000-2,500 feet per minute (fpm). It is desirable to run both the press, folder and other equipment in the printing press line at the highest speed possible to produce as many printed products as possible in a given amount of time. However, the physical qualities of printed paper or similar flexible substrates moving at a high rate of speed can result in undesirable whipping, dog-earring, tearing, smearing of the ink, or bunching of the substrate. Additionally, impact between the leading edge of a signature and a diverter wedge may result in the leading edge of the signature being dented or dog-eared or damaged in other ways. Moreover, the trailing edge of a signature may slap against the top edge of a diverter wedge, resulting in tears, dog-ears or other damage to the trailing edge. Damaged signatures may be of reduced or unacceptable quality and may also lead to jams in the folder, resulting in downtime, repair expense and much wasted paper. 
     Another problem which occurs when operating a press and a folder at high speeds is that signatures may be routed to an undesired one of a plurality of collation paths. As the leading edge of a signature approaches the apex of a diverter wedge, depending on the stiffness of the signature and due to the relationship between the diverter and the diverter wedge, the signature may be delivered to the wrong side of the diverter wedge thereby sending the signature down the wrong collation path. This leads to jams in the folder causing delays and expense. 
     Yet another problem when operating a printing line at high speeds concerns ink offset in the diverter. As a signature impacts a diverter wedge, non-dried ink may transfer to the surface of the diverter wedge. As successive signatures contact the diverter wedge, the ink transferred to the diverter wedge may undesirably pass to the other signatures. The greater the impact of the signatures against the diverter wedge, the greater the likelihood of ink offset. 
     Many of the foregoing defects become more prevalent above certain speeds of the printing press and folder. For example, such defects may occur when the press is run at speeds greater than 2,500 fpm, but may not occur when the press is run at a slower speed, for example, 2,200 fpm. As printing press speed capabilities have increased, it has become increasingly important to provide a system which allows for individual signatures to be directed down any one of a plurality of selected collation paths without damaging the leading or trailing edge of each signature or causing jams. 
     U.S. Pat. No. 4,373,713 discloses a diverter mechanism placed in a path of a stream of cut sheets comprising a pair of rotary diverters with raised cam surfaces used to divert and guide the sheets. A tapered guide has a pair of diverging guide surfaces and has its upstream tapered end interposed between the rotary diverters with raised cam surfaces and diverging tapes. 
     A sheet diverter for signature collation and a method thereof is described in U.S. Pat. No. 4,729,282, assigned to Quad/Tech, Inc., of Pewaukee, Wis., and is hereby incorporated by reference. The &#39;282 patent discloses a sheet diverter including an oscillating diverter guide member that directs successive signatures to opposite sides of a diverter wedge. As set forth in the &#39;282 patent, the diverter design disclosed in the &#39;713 patent is not viewed as workable in light of the high speeds sought to be attained nor is it seen to be particularly reliable in reducing jamming tendencies which are expected to arise in these settings. 
     SUMMARY OF THE INVENTION 
     Diverting devices are used in the printing industry to divert individual signatures along alternating paths in the folder part of a printing press line. Because the diverting operation has a slow processing velocity in relation to the rest of the line, the industry seeks to speed up this operation while reducing damage to the signatures and avoiding jams. 
     There is a need for a sheet diverter that is capable of operating at high speeds, e.g., in excess of 2,500-3,000 fpm and above, and yet also capable of providing a signature that is acceptable in quality. What is also needed is a sheet diverter for use in the printing industry such that the sheet diverter improves the collation process of printed signatures to prevent or minimize damage to the signatures as the signatures move along one of a plurality of collation paths to increase the quality of each signature, allow for greater operational speeds and reduce downtime and repair expenses associated with jams in a folder. What is further needed is a sheet diverter for use in a high speed printing press line which is designed to prevent or minimize the transfer of non-dried ink to a diverter wedge of the sheet diverter thereby enhancing the overall quality of the printed signatures. 
     In one embodiment of the present invention, a diverter assembly for diverting signatures from a diverter path to a desired one of a plurality of collation paths is provided. A pair of spaced apart, rotating diverter rolls have respective travel paths which define a common swipe path for the diverter rolls. A diverter wedge which separates the plurality of collation paths is positioned between the pair of diverter rolls such that a portion of the diverter wedge extends into the common swipe path. Positioning the diverter wedge in the common swipe path of the diverter rolls allows for increased control over signatures traveling through a folder as compared to prior known apparatus and methods thereby allowing for greater operational speeds, decreasing signature damage, less ink offset to the diverter wedge and reducing jamming tendencies in a folder. 
     In another embodiment of the present invention, a sheet diverter for diverting signatures delivered from a printing press to a selected one of a plurality of collation paths is provided. The sheet diverter includes an oscillating diverter device for directing a leading edge of a signature to one of the plurality of collation paths. The sheet diverter also includes a diverter which separates the plurality of collation paths for deflecting a signature to a selected one thereof. The oscillating diverter device and the diverter are capable of intermeshing at appropriate times so as to increase control over signatures traveling through a folder as compared to prior known apparatus and methods thereby also allowing for faster operational speeds, decreasing signature damage, less ink offset and reducing jamming tendencies in a folder. 
     In yet another embodiment of the present invention, a method for collating signatures delivered from a high speed printing press is provided. A signature is delivered to a pair of oscillating diverter rolls which generally translate over a reciprocable path which is generally normal to the path of the signatures. The translation of the diverter rolls with respect to a diverter wedge positioned therebetween is such that damage to the signatures is substantially minimized or prevented as the signatures travel to and past the diverter wedge thereby allowing for increased operating speeds with fewer jams. The translation of the diverter rolls is properly timed or adjusted with respect to the approach or position of the signatures in relation to the diverter rolls. 
     Accordingly, it is a feature of the present invention to provide an apparatus and a method thereof that minimizes the potential for damage to signatures as they travel down one of a plurality of collation paths, while also allowing for increased operating speeds. 
     Another feature of the present invention is to provide a sheet diverter in a printing press operation that provides for improved collation of signatures therethrough while eliminating the need for expensive, complicated equipment as is currently used in the industry. Thus, a feature of the invention is to provide a simple, inexpensive device to improve the collation process in a sheet diverter of a printing press and folding operation. 
     Yet another feature of the present invention is to provide a diverter in a printing press capable of operating at excessive speed, e.g., in excess of 2,500-3,000 fpm and above, and yet also capable of producing signatures of acceptable quality standards, while at the same time reducing jams which would normally occur in prior known devices if such devices were operated at the contemplated rates of speed discussed herein, all of which thereby minimizes machine downtime and repair expenses, and increases product output over a specified period of time. 
     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partial schematic diagram of a pinless folder incorporating a sheet diverter in which the present invention may be employed. 
     FIG. 2 is a partial perspective view of portions of a sheet diverter according to the present invention. 
     FIGS. 3-5 are cross section side views of a sheet diverter according to the present invention showing the advancement of a signature past a diverter as the signature travels to a selected one of a plurality of collation paths. 
     FIG. 6 is an enlarged view of a portion of the sheet diverter shown in FIGS. 3-5. 
     FIG. 7 is a front view of a sheet diverter of the present invention with one diverter roll removed showing the relationship between certain components of the sheet diverter. 
     FIG. 8 is a cross section side view of a diverter wedge of a sheet diverter according to another embodiment of the present invention. 
     FIG. 9 is an illustrative view of a sheet diverter wedge of a sheet diverter according to yet another embodiment of the present invention. 
     FIG. 10 is an illustrative view of the sheet diverter of FIG. 1 showing in greater detail another aspect of the present invention. 
    
    
     Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The use of “consisting of” and variations thereof herein is meant to encompass only the items listed thereafter. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Illustrated in FIG. 1 of the drawings is a partial schematic diagram of a pinless folder  10  which is a portion of a high speed printing press (not shown). A typical folder includes a forming section, a driving section, a cutting section, a diverting section and a collating section. The invention described herein is primarily directed to a diverter section. A description of a typical forming section, driving section, cutting section, and collating section is found in U.S. Pat. No. 4,729,282, which has been incorporated herein by reference. Shown in FIG. 1, among other things, is a diverter section  12  in which the present invention may be employed. 
     Upstream of the diverter section  12  shown in FIG. 1, a forming section, such as that described in the &#39;282 patent, may be provided which may include a generally triangularly shaped former board which receives a web of material (or several longitudinally slit sections of the web termed “ribbons”, wherein the ribbons are typically aligned one on top of the other) and folds the same. The fold is in a direction parallel to the direction of web travel. The folded web is then fed downwardly through a drive section and a cutting section in like manner as that also described in the &#39;282 patent. 
     Once the web has been transformed into a plurality of individual signatures, successive signatures enter the diverter section  12  along a diverter path  14 . The signatures are led serially via opposed tapes or belts  16  and  18  to a sheet diverter  20 , which includes an oscillating diverter device  22  and a diverter  24 . The diverter assembly  20  deflects a signature to a selected one of a plurality of collation paths  26  or  28 . The signature then enters a collating section  30  and is transported along one of the collation paths to a destination such as a fan delivery device  32  and subsequently to a conveyor (not shown), such as a shingling conveyor, as is known in the art. 
     The diverter device  22  of the sheet diverter  20  includes a pair of oscillating counter-rotating diverter idler rolls  34  and  36  eccentrically located on driven counter-rotating shafts. The diverter device  22  operates to direct the lateral disposition of the leading edge of a signature relative to the diverter  24  which separates the two collation paths  26  and  28 . The diverter device  22  generally reciprocates in a diverter plane which has a component generally perpendicular to the diverter path  14 . 
     Signatures are routed through the diverter path  14  and to a selected one of the collation paths  26  or  28  under the control of a signature controller means including a primary signature controller  38  and secondary signature controllers  40  and  42 . Preferably, the distance through the sheet diverter  20  between the primary signature controller  38  and respective secondary signature controllers  40  and  42  is less than the length of the signature to be diverted. In this way, the selected secondary signature controller  40  or  42  assumes control of the leading edge of a signature before the primary signature controller  38  releases control of the trailing edge of the same signature. As used herein, the leading edge or end and trailing edge or end refer to the first or last inch or so of a signature length, but, may actually be as much as the first or last three inches or so of a signature length. 
     The primary and secondary signature controllers  38 ,  40  and  42  comprise opposed (face-to-face) belts or tapes  16  and  18  disposed over rollers in endless belt configurations. The primary signature controller  38  includes the first diverter belt  16  and the second diverter belt  18  which circulate in separate continuous loops in the directions shown by the arrows in FIG.  1  and are joined at a nip between a set of idler rollers  44  near the outfeed of a cutting section (not shown), as such is described in the &#39;282 patent. Drive rollers  46  and  48  drive the diverter belts  16  and  18  respectively about, among other certain components in the separate continuous loops, idler rollers  44 , a plurality of idler rollers  50 , signature slow down mechanisms  52 , idler rollers  54  and  56 , and idler rollers  58  and  60 . The diverter belts  16  and  18  are also driven around idler guide rollers  64 . Both diverter belts  16  and  18  are driven by respective drive rollers  46  and  48  at the same speed, which typically is from 8% to 15% faster than the speed of the printing press. The faster speed of the belts  16  and  18  causes a gap to occur between successive signatures as the signatures move serially and in tandem down path  14  between the diverter belts  16  and  18 . Preferably, for a signature having a length of about 10.875 inches, the gap between successive signatures is approximately between about 1 to 2 inches. Signatures travel generally vertically downward past the diverter  24  along collation paths  26  and  28  so that the signatures are bent as little as possible to avoid damage due to wrinkles at the backbone of the signature and to reduce tail whip of the signatures. 
     Located downstream of idler rolls  44  is a soft nip  66  defined by an idler roller  68  and an abaxially disposed idler roller  70 . The rollers  68  and  70  cause pressure between diverter belts  16  and  18  as these belts follow the diverter path  14  through the soft nip  66 . The soft nip  66  compressively captures and positively drives a signature that passes therethrough. 
     The primary signature controller  38  includes an idler guide roll  72  which, with the aid of diverter belts  16  and  18 , helps direct a signature to the oscillating diverter device  22 . A soft nip, similar to soft nip  66 , is defined between idler roll  70  and the abaxially disposed roller  72 . 
     The secondary signature controllers  40  and  42  include a first collator belt  74  and a second collator belt  76 , respectively, which both circulate in separate continuous loops in the directions shown by the arrows in FIG.  1 . The opposed collator belts  74  and  76  share common paths with the diverter belts  16  and  18  along the collation paths  26  and  28 , beginning downstream of the diverter  24 . In particular, collator belt  74  is transported around idler rollers  64  and  78 , roll  80  of the respective signature slow down mechanism  52 , idler roller  82 , drive roll  84  and idler roll  86 . Collator belt  76  is transported around idler roller  64 , snubber roller  88  of the respective signature slow down mechanism  52 , idler rollers  90 ,  92 ,  94 , drive roll  96  and idler roll  98 . Idler rollers  100  and  102  also define the paths of the collator belts  74  and  76 . Idler rolls  82  and  94  are belt take-up rolls and are operable to adjust the tension in each belt loop. The tension of diverter belts  16  and  18  can also be adjusted with belt take-up rollers A and B, which are connected via a pivotable lever arm to an air actuator (not shown) that applies adjustable pressure. Since the tension in all four belts can be adjusted, adjustable pressure between opposed belts results to positively hold and transport signatures at tape speeds. Belts  16  and  18  are driven at the same speed as are belts  74  and  76  through the use of timing belts and timing pulleys (not shown). 
     The secondary signature controller  40  includes a soft nip  104  defined by idler roller  58  operating with the abaxially disposed idler roller  86 , the diverter belt  16 , and the collator belt  74 . Similarly, the secondary signature controller  42  includes a soft nip  106  defined by idler roller  60  operating with the abaxially disposed idler roller  98 , the diverter belt  18 , and the collator belt  76 . 
     Shown in FIG. 2 are parts of a sheet diverter according to one embodiment of the present invention. Shown are the diverter device  22  and diverter  24 . The diverter rolls  34  and  36  of the diverter device  22  include outwardly extending, spaced apart, preferably crowned, steps  118 , the function and purpose of which will be explained below. The diverter or diverter wedge  110  mounts to fixture  120  which is appropriately placed stationary in a folder so as to properly locate and firmly support diverter wedge  110  with respect to diverter rolls  34  and  36 . The diverter wedge  110  includes diversion surfaces  114  and  116  diverging from a top vertex  112  to a base  122  which is opposite the top vertex  112 . A diverter nip plane  107  is generally parallel with the diverter nip path  14  (FIG. 1) and extends through the top vertex  112  to the middle of the base  122  (see FIG.  9 ). With reference to FIG. 9, one embodiment of a diverter wedge is shown. Various points A-D are identified on the diversion surfaces  114  and  116  of the diverter wedge  110 . From points A to B, the diversion surfaces  114  and  116  preferably diverge from the top vertex edge  112  at approximately fifteen degrees with respect to the diverter nip plane  107  defining steeply sloped straight surfaces. From points B to C, the diversion surfaces  114  and  116  include generally curved surfaces, preferably having about a three-inch radius. From points C to D, the diversion surfaces  114  and  116  define generally straight surfaces which lead into the respective collating sections and directly into respective soft nips  104  and  106 . The top vertex  112  of the diverter wedge  110  preferably includes a generally rounded surface. The top vertex  112  further includes spaced apart grooves  124  (FIG.  2 ). As shown in FIG. 2, grooves  124  mesh with adequate clearance with steps  118  of rolls  34  and  36 , the function and purpose of which will be explained below. 
     An alternative embodiment of a diverter wedge is shown in FIG.  8 . Diverter wedge  111  is similar to diverter wedge  110  except that diversion surfaces  113  include respective air discharge ports  115  which are connectable to a source of pressurized air  117 . The air pressure can be adjusted with external air pressure regulators or needle valves, known to those skilled in the art. Ports  115  are preferably evenly spaced holes extending through the diversion surfaces  113  in the diverter wedge  111 . The air directed through the diversion surfaces  113  assists in sending the signatures down the collation paths by ensuring that the signatures do not stick to and are not appreciably slowed down by the diversion surfaces of the wedge by reducing friction between the diversion surfaces  113  and the signatures. 
     FIGS. 3-5 show the advancement of a signature past a diverter as the signature travels to a selected one of a plurality of collation paths. The gap of the nip  108  located between the belts  16  and  18  and respective diverter rolls  34  and  36  is preferably dimensioned to be oversized as compared to signature thickness to avoid exerting virtually any compressive force on a signature traveling through the sheet diverter  20  in the sense that a signature can be drawn through the nip  108  without rotation of the rolls  34  and  36 . In operation, at least a first and second diverter belt  16  and  18  carry individual signatures toward the sheet diverter  20  (FIG.  1 ). As the diverter rolls  34  and  36  oscillate and translate, as a result of being eccentrically located about driven counter-rotating shafts, the diverter nip  108  moves from one side to the other side of the diverter wedge  110 . A first signature is guided along one diversion surface  114  of the wedge  110 . As the signature moves through the nip  108 , the diverter rolls  34  and  36  continue to oscillate and translate so that nip  108  moves to the other side of the wedge  110 . In this manner, a successive signature is diverted to the other side of the wedge  110  along the diversion surface  116 . 
     The diverter rolls  34  and  36  include roll centers  126  and  128 . The diverter rolls  34  and  36  rotate about their respective centers and are caused to do so by virtue of being in contact with respective belts  16  and  18 . The diverter rolls  34  and  36  are also journalled for rotation about respective axes  130  and  132  lying in a diverter plane  134  which has a component generally normal to the diverter path  14  of the signatures. Axes  130  and  132  extend lengthwise through the respective rolls  34  and  36 . Preferably, the diverter rolls  34  and  36  are eccentrically located upon respective driven shafts  131  and  133  wherein the axes  130  and  132  lying in the diverter plane  134  extend through respective centers of the shafts. More preferably, each of the eccentrically located diverter rolls  34  and  36  is designed to be approximately one-quarter inch off the axis of the respective shafts, to yield a full eccentric throw of about one-half inch. 
     It should be noted that in a printing press operation such as that described in reference to FIG. 1, two or more collating sections having a plurality of collating paths may be provided. As shown in FIGS. 2-5, diverter rolls  34  and  36  cooperate with collation paths  26  and  28 . Although not shown in FIG. 2, a second sheet diverter, comprising a mirror image of sheet diverter  20 , may be provided adjacent to sheet diverter  20 . In such an arrangement, more than two collation paths are used to assemble magazines or the like. 
     Referring again to FIGS. 3-5, it can be appreciated that as the diverter rolls  34  and  36  rotate about their own axis  126  or  128 , the roll centers  126  and  128  are caused to orbit about the respective shaft centers  130  and  132 . The orbital motion of the diverter rolls  34  and  36  defines travel paths of the outside diameters of steps  118  for each of the diverter rolls as identified by dotted lines  136  and  138 . As shown, travel paths  136  and  138  partially overlap to define a common swipe path  140 , best seen in FIG. 6, the significance of which will be explained below. The diverter wedge  110 , separates the collation paths  26  and  28  and is interposed between the diverter rolls  34  and  36  such that a portion of the diverter wedge  110  extends into the common swipe path  140  (see also FIG.  6 ). 
     The sheet diverter  20  of the present invention routes a signature  142  to an appropriate one of the collation paths  26  or  28  by placement of the leading edge  144  of that signature into appropriate proximate contact with the diverter  24 . In the illustrative embodiment, the diverter wedge  110  is orientated toward the diverter nip  108  and the diversion surfaces  114  and  116  taper downwardly from the apex  112  toward the collation paths  26  and  28 . The belts  16  and  18  are preferably a part of a separate group of segmented belts. With reference to FIG. 7 in conjunction with what is shown in FIG. 2, it can be observed that the belts  16  and  18  are in operative engagement with respective rolls  34  and  36 . Preferably, for every step  118  of rolls  34  and  36 , a separate belt is in operative engagement with that step. The steps  118  are generally crowned to assist in tracking of the belts as they traverse over the steps. The belts  16  and  18  diverge from a point intermediate the diverter rolls  34  and  36  and the diverter wedge  110  along distinct collation paths. The belts  16  and  18  confine a signature  142  therebetween for transport to the diverter wedge  110  such that the signature does not come into contact with either of the diverter rolls  34  or  36 . 
     With continued reference to FIGS. 3-5, signature passageways  148  and  150  are formed between respective diversion surfaces  114  and  116  of the diverter wedge  110  and the respective diverter belts  16  and  18 . As the diverter device  22  reciprocates in the diverter plane  134 , the leading edge  144  of the signature  142  is caused to enter one or the other of the signature passageways  148  or  150 . The diverter belts, diverter rolls and diverter wedge are cooperatively arranged so as not to substantially hinder or pinch a signature as the signature travels down a diverter path, past a diverter to a selected one of a plurality of collation paths. 
     FIG. 3 shows the leading edge  144  of a signature  142  approaching the top vertex  112  of wedge  110 . As shown, diverter rolls  34  and  36  are positioned along their respective travel paths  136  and  138  so as to direct the leading edge  144  of the signature to one side of the diverter wedge  110 . The timing of the translation of the diverter rolls  34  and  36  is such that the leading edge  144  of the signature  142  will not contact the apex  112  of the diverter  110  which, if it did occur, may damage the leading edge of the signature and could cause a jam in the diverter. 
     As is apparent in FIG. 3, passageway  148  is open and passageway  150  is practically closed. Passageways  148  and  150  tend to open and close as the diverter rolls  34  and  36  reciprocate in the diverter plane  134 . In prior designs, at excessive speeds, because of the relationship between the diverter rolls and the diverter wedge, a signature could be directed down a wrong collation path as a result of passageways on either side of a diverter wedge not being sufficiently closed. As shown in FIG. 3, because the diverter wedge reaches into the common swipe path  140  of the diverter rolls  34  and  36 , and because the rolls  34  and  36  translate in a reciprocable path, the passageway  150  is sufficiently closed to prevent the signature  142  from being directed down the wrong collation path, in this case, collation path  28 . 
     FIG. 4 shows the leading edge  144  of signature  142  as the signature is first guided into initial contact with the diverter wedge  110 . The top vertex  112  and diversion surfaces  114  and  116  of the diverter  24  are designed as set forth above to ease the passage of the signatures along the collation paths. The vertex  112  is preferably rounded to assist in reducing damage to the leading edge or trailing edge of a signature if such should contact the vertex  112 . The upstream portion of the diversion surfaces  114  and  116  are steeply sloped and liberally curved (FIG. 9) to reduce the impact force acting on the leading edge  144  of the signature  142  as it strikes against the diverter wedge  110  and to reduce the rubbing pressure on the side of the signature which travels against the diverter wedge so as to prevent or reduce ink offset. The signature  142  is continually advanced along collation path  26  as rolls  34  and  36  rotate and translate. As can be observed in FIG. 4, with reference to FIG. 6, steps  118  of roll  36  extend beneath diversion surface  116  of wedge  110  during part of the full rotation such that diverter roll  36  meshes with diverter wedge  110 . The steps  118  mesh with grooves  124  of wedge  110  so as not to cause damage from a collision to the diverter roll  36  and diverter wedge  110 . The meshing action between the diverter roll  36  and diverter wedge  110  allows the diverter wedge  110  to extend into the common swipe path  140  of the diverter rolls  34  and  36 . As noted, control over the signature is increased by placing the diverter wedge  110  in the common swipe path  140  of the diverter rolls  34  and  36 . 
     FIG. 5 shows the trailing edge  146  of the signature  142  as it approaches the apex  112  of diverter wedge  110 . As the diverter rolls  34  and  36  translate along plane  134 , passageway  148  is closing and passageway  150  is opening. The translation of the rolls  34  and  36  is such that the trailing edge  146  of the signature will not be slapped violently against the vertex  112  which would cause tailwhip. This is prevented because the diverter wedge  110  reaches into the common swipe path  140 . The signature  142  is more fully supported as the belts  16  and  18  diverge from the rolls  34  and  36 . In prior sheet diverters, the diverter wedge may be located substantially distant from the diversion point of the belts. Thus, in such prior designs, a significant portion, including the trailing edge, of a signature may be whipped against and across the top vertex of the diverter wedge thereby damaging the trailing edge as set forth above. 
     Timing the translation of the diverter rolls to the arrival time of the signatures as the signatures are collated from a high speed printing press is one aspect of the present invention. The timing of the translation, which may be manual, semi-automatic or automatic, should be controlled such that when a leading edge of a signature is adjacent to an uppermost portion of a diverter, the diverter rolls direct the leading edge of the signature to one side of the diverter so that the signature leading edge does not contact the top vertex. Moreover, timing the translation of the diverter rolls should be such that the trailing edge of the signature will not whip against the top portion of the diverter as the signature continually travels along the selected collation path. 
     With reference to FIG. 4, a preferred embodiment of the invention will be described. The timing of the translation of diverter rolls  34  and  36  is preferably based on the point in time when the leading edge  144  of the signature  142  first contacts a diversion surface of the diverter wedge  110 . As previously explained, roll centers  126  and  128  are caused to orbit about respective axes  130  and  132 . Position “X” is defined as the angular location of the centers  126  and  128  of diverter rolls  34  and  36  with respect to axes  130  and  132  and plane  134  when the signature first contacts the wedge  110 . In position “X”, it can be observed that roll center  126  is located to the left and below axis  130  and roll center  128  is located to the left and above axis  132 . Diverter roll  34  is located about its travel path  136  in the position shown such that roll center  126  falls on a plane  152  traveling through roll center  126  and axis  130 , the plane  152  being set at a preferred angle of between about 25-45 degrees with respect to plane  134 . Diverter roll  36  is located about its travel path  138  in the position shown such that roll center  128  falls on a plane  154  traveling through roll center  128  and axis  132 , the plane being set at a preferred angle of between about 25-45 degrees with respect to plane  134 . Preferably, the numerical angle value for locating roll  34  with respect to plane  152  and plane  134  is equal to the numerical angle value for locating roll  36  with respect to plane  154  and plane  134 . 
     Timing the translation and positioning of rolls  34  and  36  as set forth with respect to FIG. 4 ensures that as a leading edge of a signature approaches apex  112  (FIG.  3 ), the leading edge will not sufficiently contact or sufficiently misses the vertex  112  and the signature  142  will not be directed down the wrong collation path  28 . As shown in FIG. 3, rolls  34  and  36  have not yet reached position “X” as identified in FIG.  4 . However, based on the timing of the translation of the rolls in order to reach position “X”, the position of the rolls  34  and  36  is timed such that passageway  150  is sufficiently closed and passageway  148  is sufficiently opened so that rolls  34  and  36  properly direct the leading edge  144  of signature  142  to collation path  26 . In addition, proper timing and positioning of the rolls  34  and  36  will ensure that as a trailing edge of a signature approaches apex  112  (FIG.  5 ), the trailing edge will not be violently whipped or slapped against or across the apex  112 . As shown in FIG. 5, rolls  34  and  36  have translated beyond position “X” as described in FIG.  4 . The translation of the rolls  34  and  36  is timed such that passageway  148  is closing and passageway  150  is opening so that signature  142  is properly directed down collation path  26  and a succeeding signature will be fed down collation path  28 . 
     It should be noted that for every 180 degrees the drive shafts rotate, one signature travels past the rolls. Thus, with reference to FIGS. 3-5, and particularly the just described preferred embodiment, when a succeeding signature is directed to collation path  28  and the signature contacts a surface  116  of a wedge  110 , the location of rolls  34  and  36  will be reversed with respect to the description related to FIG.  4 . 
     The operation of the present invention may be further explained as follows. As described, when the diverter rolls  34  and  36  translate over a path in the diverter plane  134  in order to direct a signature  142  to a wedge  110 , passageways  148  and  150  tend to open and close. As illustrated in FIG. 4, when the signature  142  contacts the wedge  110 , grooves  124  in wedge  110  mesh with sufficient clearance with steps  118  of roll  36 . It should be noted that although the steps  118 , and thereby belts  18 , extend beneath diversion surface  116 , the belts  18  preferably do not contact any part of wedge  110  because such contact may cause the belts to adversely wear. As is apparent with reference to FIG. 5, as a succeeding signature is directed to collation path  28 , grooves  124  in wedge  110  will appropriately mesh with sufficient clearance with steps  118  of roll  34 . In this way, the grooves  124  intermittently mesh with steps  118  of rolls  34  and  36 . It should be noted that the timing of the translation and thereby the meshing action of the rolls and wedge is such that the signatures are not hindered or pinched as they travel from the diverter path to the collation paths. As should be evident, if a roll, such as roll  34 , meshes with grooves  124  in the wedge  110  before a signature has traveled past the apex  112  on its way down the collation path  26 , the signature would be pinched between the belts  16  and wedge  110  thereby causing damage to the signature and possibly jamming the machine. 
     FIG. 10 is an illustrative view of the sheet diverter of FIG. 1 showing in greater detail another aspect of the present invention. As a signature  142  is traveling past a diverter wedge  110  in a diverter section, it is desirable to prevent the signature  142  from being bent in more than one direction so as to reduce tail whip of the trailing edge  146  of the signature  142  as it travels past the vertex  112  of the diverter wedge  110 . As such, from the point the diverter belts  16  and  18  generally release from respective diverter rolls  34  and  36  to the point the diverter belts  16  and  18  generally engage respective rolls  54  and  56 , the diverter belts  16  and  18  travel in a substantially straight line. The distance between these two points is approximately equal to about the length of one signature. In this way, as a signature  142  travels down one of the collation paths  26  or  28 , the leading edge  144  of a signature  142  will not be directed in another direction until the trailing edge  146  of the signature  142  has traveled past the apex  112  of the diverter  24 . Thus, reducing the likelihood that the trailing edge  146  will be violently whipped against or across the apex  112  of the diverter  24 . In order to achieve the foregoing features, idler rollers  58  and  60  are adjustable generally perpendicular to the respective belt or collator paths  26  or  28  and idler rollers  54  and  56  are adjustable generally parallel to the respective belt or collator paths  26  or  28 . 
     It is readily apparent from the foregoing detailed description that the sheet diverter of the present invention overcomes the problems of the prior art. The sheet diverter of the present invention may function efficiently in conjunction with a high speed printing press at sheet speeds in excess of 2,500-3,000 fpm or more. Sheets are efficiently diverted into appropriate collation paths at these high speeds with reduced damage to the sheets and with reduced jamming tendencies. Anticipating the occurrences of such jams, which although reduced in tendency could never be made non-existent, the diverter rolls may be designed to pivot away from each other through the use of air cylinders or the like in order to open up a region near the collation paths and diverter so jammed product can be removed. Thus, even in the event of jams, the downtime associated with clearing the apparatus is greatly reduced. 
     The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention in the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings in skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described herein are further intended to explain the best modes known for practicing the invention and to enable others skilled in the art to utilize the invention as such, or other embodiments and with various modifications required by the particular applications or uses of the present invention. It is intended that the appended claims are to be construed to include alternative embodiments to the extent permitted by the prior art. 
     Various features of the invention are set forth in the following claims.