Abstract:
A transfer wheel removes flat products from one location, such as an overhead conveyor, spaces the products apart, reorients them and then transfers the products to a second conveyor or other location. The transfer wheel is eccentrically mounted within a circular frame. Grippers mounted on radially-moving spokes of the transfer wheel rotate as the wheel turns, to reorient the products, for example from vertical to horizontal, so they can be laid flat on the second conveyor. The eccentric mounting of the wheel causes the spokes to increase the spacing between adjacent products as the wheel turns, to prepare the products for later processing.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application is entitled to the benefit of U.S. Provisional Patent Application Ser. No. 60/692,696, filed Jun. 21, 2005. Such application is incorporated herein by reference. 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a device for transferring flat, flexible products from one location, such as a conveyor, to another location. The invention is especially useful for transporting newspapers between two conveyors and reorienting them for later feeding to a bagging machine. 
   2. Art Relating to the Invention 
   In the graphic arts industry, flat, flexible, printed products, such as newspapers and magazines, are often moved from one processing machine, such as an inserter, to another machine or location by line conveyors having grippers. The product is typically carried in a vertical, hanging orientation, one product per gripper. At some point along the path, the product has to be transferred from the line conveyor to another conveyor or other location, for later transport to a bagging or other machine for further processing. Very high transport speeds are necessary. 
   Typically, a line conveyor, as employed in the graphic arts industry, is a horizontally oriented endless chain that is equipped with a plurality of vertically oriented grippers moving overhead of other machines. The grippers clamp the top edge of the product and transport the product along. When the product arrives at its destination, the gripper opens its jaws to allow the product to fall or be removed from the conveyor to another area. 
   For proper handling by a bagging machine, the vertically hanging products on the overhead line conveyor need to be reoriented into a horizontal position and laid on another conveyor or other device in a serial or “singulated” arrangement, namely one product after another, flat and in single file. The spacing distance between adjacent products is also important. At present, for newspaper products, the spacing between each adjacent singulated product needs to be approximately fourteen inches, for proper, high-speed bagging to take place. However, the spacing between the vertically hanging products on the line conveyor is normally less than that, such as six inches or so, because a shorter spacing is needed to help maximize product flow speed along the conveyor. 
   Thus, a need exists for a high-speed transfer device that effectively (1) removes vertically oriented products from a line conveyor; (2) orients the products horizontally; (3) increases the spacing between the products; (4) singulates the products; and (5) transfers the products to another conveyor or other area for subsequent proper handling by a bagging machine or other processing machine. 
   SUMMARY OF THE INVENTION 
   It has now been discovered that, by employing a transfer wheel invention that operates as a circular gripper conveyor, a smooth and rapid transfer of the product occurs from the overhead line conveyor to an underneath singulating conveyor. The transfer wheel is eccentrically mounted within a circular frame. Movable grippers mounted on movable and pivotable spokes of the transfer wheel rotate as the wheel turns, to serially grab the products from an overhead line conveyor, space them apart, reorient them, and then deposit them flat on the singulating conveyor beneath the wheel. For example, the products can be reoriented from a vertical position to a horizontal position. 
   The outside ends of the spokes are attached to sliders that slide along a track or groove formed in the circular frame. As the transfer wheel rotates, the sliders continuously push and pull the spokes out and in radially, due to the eccentric mounting of the wheel. When the spokes move out, the outside ends of the spokes move apart, thus increasing the spacing distance between adjacent grippers (and their gripped products) as the wheel turns. In this way, the transfer wheel, which may also be referred to as a “singulating gripper wheel,” properly orients and spaces apart the products, and then transfers them serially to the singulating conveyor, which then transports them away to a wrapping or bagging machine or other processing area. 
   More particularly, in one embodiment, the present invention comprises a device for transferring flat products from a first location to a second location, comprising: 
   a wheel rotatably mounted between said first location and said second location; and 
   a plurality of movable grippers mounted to the wheel around its periphery; 
   whereby, as the wheel rotates, each gripper grips one of said products from the first location, increases a spacing distance between adjacent gripped products, and moves each product serially to the second location. 
   In another embodiment, the present invention comprises a transfer wheel device for transferring, spacing apart and reorienting a plurality of flat, flexible, vertically-oriented products from a first conveyor to a second conveyor, comprising: 
   a rotatable transfer wheel mounted eccentrically within a circular frame, below said first conveyor and above said second conveyor; 
   a plurality of bearing blocks pivotally mounted to the transfer wheel around its periphery; 
   an approximately radially-oriented spoke slidably held within each of said bearing blocks; and 
   a movable gripper mounted to a slider attached to an outside end of each spoke; 
   whereby, as the transfer wheel rotates, each gripper serially grips one of said products from the first conveyor, increases a spacing distance between adjacent gripped products, reorients each product to an approximately horizontal position, and deposits each product serially on the second conveyor. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other aspects of the present invention may be more fully understood by reference to one or more of the following drawings, in which: 
       FIG. 1  is a side view of the transfer wheel of the present invention; 
       FIGS. 2-5  are a series of perspective, simplified views of the transfer wheel of  FIG. 1 , showing a time sequence of operations of elements of the wheel as the wheel rotates clockwise through four positions; 
       FIG. 6  is a side view of a machine incorporating an alternative embodiment of the transfer wheel of the invention, the machine being shown positioned near a feeder of an insert machine, underneath a linear gripper conveyor, and over a wrapping or bagging machine; 
       FIG. 7  is a front view of the machine of  FIG. 6 ; 
       FIG. 8  is a top view of the machine of  FIG. 2 ; 
       FIG. 9  is a simplified perspective view of the transfer wheel shown in  FIG. 6 ; and 
       FIG. 10  is a simplified perspective view of a gripper cam mechanism used with the transfer wheel shown in  FIG. 6 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the present application, reference is made to newspaper jackets or, more simply, jackets, as the flat, flexible, printed product. Each newspaper within the jacket typically contains a number of loose inserts. It will be understood that other products besides newspapers can be handled by the present invention. In addition, while the present invention is particularly useful for positioning newspapers on a conveyor or other device for proper transportation to a wrapping or bagging machine, it will be understood that the invention may also be used to transport flat products to other processing machines or locations. 
     FIG. 1  illustrates a preferred embodiment of the present invention. One general mechanical principle employed in the invention is that of a slider crank mechanism. In a feature of the invention, a circular, rotatable transfer wheel  85  is eccentrically mounted within a circular frame  57 . Transfer wheel  85  is preferably comprised of two metal disks mounted to each other, parallel to each other, slightly spaced apart and having a common axis of rotation. This arrangement is best seen in  FIGS. 2-5 . 
   In the illustrations of FIGS.  1  and  2 - 5 , the wheel is arranged to rotate clockwise by a motor (not shown) driving gears, chains or a belt. If desired, the belt can be driven from the overhead gripper conveyor, as can be seen in  FIG. 6 . The axis of rotation of wheel  85  is preferably offset away from the imaginary center of circular frame  57 , and is preferably closer to the top of circular frame  57  than to the bottom. The degree of eccentricity in the mounting may be varied depending upon the amount of spacing that is desired between products as the wheel turns (discussed below). 
   In a preferred embodiment, transfer wheel  85  is positioned below a line conveyor  51 , and above a singulating conveyor  90 . Line conveyor  51  has a plurality of line conveyor grippers (not shown) that hold jackets  2  of a newspaper in a vertical, hanging orientation. Typically, the newspaper will be folded, with the folded, closed side on the bottom to prevent inserts from falling out. In the illustration of  FIG. 1 , the jackets  2  are moved by line conveyor  51  toward the right. Singulating conveyor  90  moves toward the left. In  FIG. 1 , it can be seen that jackets  2  are lying horizontal on conveyor  90 . Conveyor  90  can be used to transport the newspapers to a wrapping or bagging machine. 
   Transfer wheel  85  is operated in synchronization with line conveyor  51  and singulating conveyor  90 , to ensure that the circumferential speed of the grippers  3  on the wheel is the same as the linear speed of the products  2  moving along the conveyors  51  and  90 . 
   In another feature of the invention, and as shown in FIGS.  1  and  2 - 5 , pivotally mounted between the disks of transfer wheel  85  and around its periphery are a plurality of bearing blocks  80 , which function somewhat like hollow articulating joints. In the present embodiment, 16 bearing blocks are employed, and they are spaced equally apart around the circumference of wheel  85 . 
   Slidably mounted within each bearing block  80  is a spoke  82 . The outer end of each spoke is attached to a slider  4 , which is best seen in  FIG. 3 . The inner end of each spoke is unattached. Each slider  4  is slidably mounted within a track or groove  91  that is formed around the periphery of circular frame  57 , as shown in  FIGS. 1 ,  2  and  3 . In this arrangement, the spokes  82  assume an approximately radial orientation, pointing toward the imaginary center of circular frame  57 . 
   Attached to each slider  4  is a movable gripper  3 . Each gripper  3  has two jaws that are spring biased in a closed position. Cams are used to open the jaws. Opening cams (not shown), positioned at the top and bottom of circular frame  57 , are employed for opening the jaws to grab a product  2  from above and release the product below. 
   In yet another feature of the invention, each gripper  3  is rotatable. For example, as seen in  FIG. 1 , the jaws of the grippers at the top, bottom and left side of the circular frame  57  are facing away from transfer wheel  85 , whereas the jaws of the grippers on the right side of frame  58  have rotated to the left, in a direction opposite to the direction of rotation of the transfer wheel  85 . Typically, the grippers will rotate by approximately 90 degrees. This changes the orientation of the product from vertical to horizontal after the product has rotated approximately halfway around the wheel. 
   In order to help control the movement of jacket  2  during its downward decent from line conveyor  51  to singulating conveyor  90 , a curved guide (see  FIG. 6 ) is mounted slightly away from the right side periphery of circular frame  57 . As will be appreciated, each gripper  3  grabs the bottom edge of a jacket  2 , and the guide helps maintain the top edge of jacket  2  in an upward-facing direction during its downward movement. This assists in preventing inserts, which are in jacket  2 , from escaping. 
   The operation of the invention will now be described, with reference to FIGS.  1  and  2 - 5 . As previously mentioned, transfer wheel  85  is rotating clockwise in these particular figures. When a gripper  3  has rotated directly under a product  2 , the jaws of the gripper close. Approximately simultaneously, the jaws of the line conveyor gripper (not shown) that are holding the product open to release the product. 
   As transfer wheel  85  continues to rotate, and as best seen in  FIG. 3 , slider  4  is sliding along track  91 . Since transfer wheel  85  is eccentrically mounted in relation to track  91 , the distance between track  91  and bearing block  80  gradually and continuously increases as the wheel rotates around its right-hand portion, and the slider  4  starts to pull its associated spoke outwardly away from the wheel. Bearing block  80  also starts to pivot gradually. These actions cause the distance between adjacent grippers to increase, which is best seen by comparing  FIG. 4  with  FIG. 3 . This, in turn, causes the spacing between adjacent gripped products to increase. 
   Meanwhile, a cam mechanism (see  FIG. 10 ) attached to each gripper causes the jaws of the gripper to rotate counterclockwise, away from the direction of rotation of wheel  85 . This action, together with the guide  36  ( FIG. 2 ), changes the movement of the product from left to right to clockwise circular, and eventually changes the orientation of the product from vertical to horizontal. 
   When a gripped product on the transfer wheel rotates into a position directly over the singulating conveyor  90 , after approximately one-half of a rotation of the wheel, the jaws of gripper  3  open, and the product is released onto conveyor  90 . The released products are now appropriately flat, singulated, separated from each other by the correct distance, and ready to be rapidly and effectively processed by a bagging machine or other processing machine. Typically, the products hanging from the overhead gripper conveyor will be spaced apart by approximately 6 inches. In a preferred embodiment, the present invention will increase the spacing between products to approximately 14 inches. 
   An alternative embodiment of the present invention is shown in  FIGS. 6-10 . More particularly,  FIG. 6  is a side view of a machine incorporating an alternative embodiment of the transfer wheel of the invention, the machine being shown positioned near a feeder of an insert machine, underneath a linear gripper conveyor, and over a wrapping or bagging machine. 
     FIG. 7  is a front view of the machine of  FIG. 6 ;  FIG. 8  is a top view of the machine of  FIG. 6 ;  FIG. 9  is a simplified perspective view of the transfer wheel shown in  FIG. 6 ; and  FIG. 10  is a simplified perspective view of a gripper cam mechanism used with the transfer wheel shown in  FIG. 6 . 
   This alternative embodiment is different from the previously-described embodiment in that the spokes are fixed, whereas the spokes  82  of  FIGS. 1 and 3  pivot as the wheel rotates. Also, the grippers around the wheel of this embodiment are spaced farther apart than the grippers of the previously-described embodiment. 
   While only a limited number of specific embodiments of the present invention have been expressly disclosed, it is, nonetheless, to be broadly construed and not to be limited except by the claims appended hereto.