Abstract:
A bell packer comprises of a rotating member combinable to a pallet for rotating the pallet, a vibrator for providing oscillatory motion, and a vibrating member engaged with the vibrator positioned apart from the rotating member for vibrating the pallet. A hopper for storing concrete slurry has an opening to a first auger and a second auger that convey the concrete slurry toward the shaft so that the concrete slurry falls to the center of a mold. A drive assembly comprises of a pair of motors configured for counter-rotation of a pair of concentric shafts with each having a gear and pulley linked by a belt wherein the pulleys are concentric with each other and the counter-rotating shafts.

Description:
[0001]    This application claims priority to U.S. Provisional Application 62/117,529 filed on Feb. 18, 2015 the contents of which are hereby incorporated by reference herein. 
     
    
     BACKGROUND 
       [0002]    This disclosure relates to a packerhead machine, and more particularly, this disclosure relates to a twin feed auger, a cross head transmission and a bell packer. 
         [0003]    In the packerhead system of concrete pipe manufacture a packerhead which consists of a rollerhead, or roller assembly, and a trowel, more frequently referred to as a longbottom, are lowered into a circular mold and rotated as they move upwardly, all the while packing wet concrete, which is dropped onto the packerhead, against the inner wall surface of the mold. 
         [0004]    Concrete pipe products typically have a tongue or male end and a socket or female end which is bell-shaped. Either end of the pipe product may be adapted to receive a gasket (e.g. rubber or other suitable material) for creating a water-tight seal between sections of the pipe when joined. The surface texture and finish of the inner socket end (the surface formed by the upper vertical and horizontal surfaces of the curing pallet) must be adequately compacted to provide the compressive and tensile strength required to resist the force applied by forcing the gasketed end or ends in place. It also is important that the inner concrete surface of the socket end be smooth and void-free to facilitate a water-tight seal. One or both of these two critical conditions frequently are not attained due, principally to the failure of the machinery to provide effective vibration during the pipe-forming process. 
         [0005]    The application of vibration to the cement slurry causes the mixture to assume a more fluid state during the vibration action, so that following the vibration procedure, the resulting vibrating product is in a more consolidated or dense state. Vibration additionally results in the finest components of the slurry being moved to the molded surfaces, thus achieving the desired surface texture. The effectiveness and efficiency of the vibrating action are dependent upon its application directly to the concrete mixture or to the mixture through a mold or machine component, in the frequency, impact, and amplitude appropriate for achieving the desired result. 
       SUMMARY 
       [0006]    A bell packer for a packerhead machine is disclosed. The bell packer comprises of a rotating member combinable to a pallet for rotating the pallet, a vibrator for providing oscillatory motion, and a vibrating member engaged with the vibrator positioned apart from the rotating member for vibrating the pallet. In this regard, the rotating member is substantially isolated from vibration from the vibrating member. In one implementation, the vibrating member and the rotating member are concentrically aligned. The bell packer can further comprise of a support structure assembly for supporting a pair of vibrators to vibrate the pallet in a vertical oscillatory motion. 
         [0007]    The support structure assembly can comprise of a pallet support structure combined to the vibrating member and mounted above a support structure. At least one opening is provided in the pallet support structure that leads to a funnel concentric with the vibrating member that receives and directs excess slurry downward. 
         [0008]    A drive mechanism is provided for rotating the rotating member. The drive mechanism is mounted to a first frame that is engaged for movement along a second frame. The bell packer can be configured to rotate the pallet simultaneous with vibrating the pallet. 
         [0009]    In another implementation, a packerhead machine can be configured with a hopper for storing concrete slurry. An opening in the hoper leads to a first auger and a second auger that convey the concrete slurry toward the shaft so that the concrete slurry falls to the center of a mold. 
         [0010]    The first auger and the second auger can be contained in a shell. A pair of motors for driving the first auger and the second auger is combined to the outside of the shell. The other end of the shell contains a pair of bearings for supporting the other ends of the first auger and the second auger, respectively. The hopper and the shell is configured to move with the drive mechanism for the packerhead while the first auger and the second auger convey concrete slurry at a substantially constant feed rate to a position concentric with the shaft. 
         [0011]    In another implementation, a drive assembly for the packerhead machine is provided. The drive assembly comprises of a pair of motors that engage a corresponding pair of transmissions, which can be configured for counter-rotation of a pair of concentric shafts. Each transmission can comprise of a gear and pulley linked by a belt wherein the pulleys are concentric with each other and the counter-rotating shafts. 
         [0012]    The above and other objects, features, and advantages will become more readily apparent from the following, it being understood that any feature described with reference to one embodiment of the invention can be used where possible with any other embodiment and that reference numerals or letters not specifically mentioned with reference to one figure but identical to those of another refer to structure that is functionally if not structurally identical. In the accompanying drawing: 
     
    
     
       BRIEF DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
         [0013]      FIG. 1  is a perspective view of a concrete pipe forming apparatus, which has been adapted with the present invention. 
           [0014]      FIG. 2  is a top-perspective view of the concrete pipe forming apparatus of  FIG. 1 . 
           [0015]      FIG. 3  is a top-plan view of the concrete pipe forming apparatus of  FIG. 1 . 
           [0016]      FIG. 4  is a side view of the concrete pipe forming apparatus of  FIG. 1 . 
           [0017]      FIG. 5  is an exploded view of a crosshead transmission for counter-rotating the main shafts. 
           [0018]      FIG. 6  is a perspective view of a bell packer. 
           [0019]      FIG. 7  is a side view of the bell packer of  FIG. 6 . 
           [0020]      FIG. 8  is an exploded view of the bell packer of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]      FIG. 1  shows a concrete pipe forming apparatus also known as a packerhead machine  100 . Generally, packerhead machine  100  has a frame  102  to bear the weight of a drive assembly  104 . Drive assembly  104  is mounted on roller guides  103  and moved by a guide mechanism  105  that moves drive assembly  104  upward and downward along frame  102 . Roller guides  103  that connect drive assembly  104  to frame  102  position drive assembly  104  with respect to frame  102  permit drive assembly  104  to move quickly and smoothly about frame  102 . 
         [0022]    Drive assembly  104  powers a roller head  107  (see  FIG. 7 ), which is a circular powered series of compacting rollers that compact concrete slurry and a trowel utilized in concrete pipe formation driven by a shaft  118 . 
         [0023]    Concrete slurry is fed into a mold  108  by a twin auger system  300 .  FIGS. 2-4  show twin auger system  300 , which includes hopper  106  for receiving and holding concrete slurry. A shell  115  is positioned beneath the opening underneath hopper  106 . Shell  115  contains a first auger  114   a  and a second auger  114   b  that are driven by a pair of motors  116   a,    116   b,  respectively, that are mounted to shell  115 . First auger  114   a  and second auger  114   b  are positioned underneath the open, bottom end of hopper  106  to convey slurry from hopper  106  to the center of shaft  118  where it flows into mold  108  as drive assembly  104  rotates and draws roller head  107  upward, packing and smoothing the concrete slurry against mold  108  in the process. The other ends of first auger  114   a  and second auger  114   b  are supported at the other end of shell  115  by a first bearing  117   a  and a second bearing  117   b,  respectively. 
         [0024]    First auger  114   a  and second auger  114   b  are positioned on either side of shaft  118  so that slurry is conveyed and deposited concentric with shaft  118 . This position allows concrete slurry to be delivered at a constant feed rate to the center of shaft  118  where it can be uniformly applied around the circumference of the mold. First auger  114   a  and second auger  114   b  can remain in a fixed position without ever having to be moved or adjusted based on the feed rate of first auger  114   a  and second auger  114   b  as the concrete slurry will always be deposited concentric with shaft  118 . As compared to a belt conveyor system, first auger  114   a  and second auger  114   b  are a more precise conveyor which allows hopper  106  to be enlarged for more holding capacity since first auger  114   a  and second auger  114   b  convey a fixed amount of material based on their design. 
         [0025]    Drive assembly  104  can have a crosshead transmission, as shown in  FIG. 5 . A first motor  120  and a second motor  122  drive a first transmission  123  and a second transmission  125 , respectively. First transmission  123  comprises of a first pulley  124  and a first gear  128 . Second transmission  125  comprises of a second pulley  126  and a second gear  130 . Respective first pulley  124  and second pulley  126  are used to drive shaft  118  which can be a pair of concentric shafts  118   a  and  118   b  to drive a counter-rotating roller head and long bottom, as described in U.S. Pat. No. 7,125,239, titled  Concrete Pipe Manufacturing Machinery and Methods,  the contents of which are hereby incorporated herein by reference. Drive shaft  118   a  is driven by pulley  126  and drive shaft  118   b  is driven by pulley  124 . Pulleys  124  and  126  are positioned between a bottom plate  132  and a top plate  134 . First gear  128  is positioned between a pair of rollers  136   a,    136   b  that hold a toothed belt  138  in position on first gear  128 . Second pulley  126  is concentric with first pulley  124  and separated by a spacer  140 . Second gear  130  is positioned between a pair of rollers  142   a,    142   b  combined to top plate  134  that hold a toothed belt  144  in position on second gear  130 . 
         [0026]    Drive assembly  104  with a crosshead transmission uses toothed belts  138  and  144  which are much cheaper than a gear box found in prior art devices. Maintenance of drive assembly  104  is also easier as only the roller bearings need lubricated. Finally, the counter-rotating pulleys self-cancel the pretension load of belts  138  and  144  on shafts  118   a  and  118   b.  A hub  119  surrounds the outer shaft bearings. 
         [0027]    First transmission  123  and second transmission  125  can comprise of a chain driven pulley system or a timing belt. 
         [0028]      FIG. 6  shows an indexing table  110  that supports mold  108  above a pit  112 . Indexing table  110  has one or more circular rings  111  to receive molds  108 . Mold  108  is positioned on the edge of circular ring  111  so that the inner area of circular ring  111  is in line with the inside of mold  108 . A bell packer  200  is located in pit  112  and fitted with a pallet  150  that is raised into the inside of mold  108 , so that pallet  150  is positioned in a bell portion  108   a  of mold  108 . Pallet  150  is used for forming the end of a concrete pipe and transporting the concrete pipe during the manufacture and curing processes. Packerhead machine  100  fills and packs mold  108  with concrete slurry. While mold  108  is being used, another mold  108  can be positioned on the empty circular ring  111 , so that when the first mold  108  is filled it can be quickly exchanged with the empty mold  108 . 
         [0029]    More specifically, bell packer  200  rotates and vibrates pallet  150  and mold  108  so that the concrete slurry fills the entirety of bell portion  108   a  of mold  108  and compacts as it settles.  FIG. 8  shows bell packer  200 . Bell packer  200  includes a frame  152  mounted by rollers  154  to frame  102  and engaged for movement so it can be moved up and down on frame  102  by a motor drive assembly  156 . A pair of vibrators  158   a  and  158   b  are mounted to opposite sides of a support structure assembly  161  that includes a support structure  160 . Vibrators  158   a,    158   b  cause a vertical oscillatory motion which is imparted to bell portion  108   a  of mold  108 . Support structure  160  is separated from frame  152  by shock absorber  162 , which can be a plurality of bushings to dampen oscillatory movement in frame  152 . A funnel  164  is combined to the top side of support structure  160  the purpose of which is discussed more thoroughly below. 
         [0030]    Support structure assembly  161  also includes a pallet support structure  166  that is positioned on top of funnel  164 . Pallet support structure  166  supports pallet  150  and imparts vertical vibratory oscillation from vibrators  158   a  and  158   b  to pallet  150 . Pallet support structure  166  includes a plurality of members  168  that connect a vibrating member  170 , which looks like a tube in the illustrated embodiment, to outer circumference  172  of pallet support structure  166 . The opening between members  168  allows excess concrete slurry to flow into funnel  164  and into pit  112  (as shown in  FIG. 7 ). At least one opening is need but as many openings as possible between members  168  while allowing pallet support member  166  to support vibrating member  170  and pallet  150  is preferred. 
         [0031]    A rotating member  174 , which looks like a tube in the illustrated embodiment, is positioned concentrically inside vibrating member  170  on pallet support structure  166 . Rotating member  174  has a plurality of members  176  that engage corresponding notches  178  in pallet  150 . On the opposite end of rotating member  174  is a plurality of members  180  that slide into corresponding notches  182  in a receiving tube  184  mounted to frame  152 . A drive mechanism which includes a motor  186  rotates receiving tube  184 , and thus pallet  150  during the concrete pipe forming process in order to pack the concrete slurry inside bell portion  108   a  of mold  108 . 
         [0032]      FIG. 7  shows a close up view of bell packer  200  engaged with mold  108 . Notches  178  of rotating member  174  are engaged in corresponding notches  178  of pallet  150 , so pallet  150  can be rotated. Vibrating member  170  combined to pallet support structure  166  engage and press up against the bottom side of pallet  150 . Vibration in the form of vertical motion or vertical oscillation from vibrators  158   a  and  158   b  is translated to pallet support structure  166  through vibrating member  170  to pallet  150 . 
         [0033]    Vibration of mold  108  is isolated from the rotation of mold  108 . Vibration from vibrators  158   a  and  158   b  is transmitted through pallet support structure  166  to bell portion  108   a  of mold  108 . Mold  108  is rotated by rotating member  174  which is separated and isolated from the vibration. By separating the vibration from the rotation there is no need for an expensive bearing assembly to counter the forces from a vibrating mass. 
         [0034]    While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it should be understood by those of ordinary skill in the art that various changes, substitutions and alterations can be made herein without departing from the scope of the invention as defined by appended claims and their equivalents.