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BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This device relates to curb forming machines that continuously slip form or extrude a pre-determined curb shape from moldable material such as concrete and the like. 
     2. Description of Prior Art 
     Prior art devices of this type typically have powered compression and extrusion augers or slip forms that travel along forming a continuous curb configuration of molded concrete material, see for example U.S. Pat. Nos. 2,707,422, 2,818,790, 3,137,220, 3,363,523, 3,779,661, 3,792,133, 4,298,293, 4,984,932 and 5,018,955. 
     In U.S. Pat. No. 2,707,422 a curb laying machine is disclosed having a fixed power auger extruder that propels the machine by pushing itself against the curb form as it is extruded. 
     U.S. Pat. No. 2,818,790 is directed to a curb and gutter-laying machine having multiple augers to extrude curb form for both a horizontal and vertical integral curb shapes are required. 
     U.S. Pat. No. 3,137,220 claims a feeding means for curb laying machines wherein curb shapes are achieved by the use of both fixed feed and auxiliary augers. 
     U.S. Pat. No. 3,363,523 described a pavement forming apparatus that forms paving material into curbs by using an external vibrating mold plate that compacts the asphalt material and moves the apparatus along. 
     Referring to U.S. Pat. No. 3,779,661 a machine and method are disclosed for preparing a sub-surface and fixed slip forming a curb thereon. This device has a grinding trimming portion and a slip form curb portion. 
     U.S. Pat. No. 3,792,133 discloses a machine for slip forming a concrete wall structure of asymmetrical transverse cross-section required in highway barrier walls. A large fixed mobile slip form is supplied material by a screw auger which extrudes the wall configuration. 
     U.S. Pat. No. 4,298,293 is directed to a curb forming apparatus for traveling along a pavement surface laying a curb on still wet pavement. This device has a slip fixed form and a supply chute utilizing a skid plate to slide along the surface. 
     In U.S. Pat. No. 4,984,932 a continuous concrete curb forming apparatus is shown having a fixed mold that can be raised and lowered as the curb is being laid so that a temporary height change can be achieved. This allows for the curb to be tapered downwardly as it nears an access area such as a driveway or the like. 
     A decorative curbing machine is disclosed in U.S. Pat. No. 5,018,955 wherein a fixed auger feeds a curb mold while being able to negotiate short radius curbing paths. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a self-powered modular curb forming apparatus that continuously forms and extrudes a curb configuration from concrete material. The apparatus provides a self-contained mobile platform in which different curb forming modules can be easily interchanged. This allows for a variety of curb forming configurations to be used in one machine. A number of curb forming techniques including power screw auger extrusion and vibratory slip forming can all be used in a single adjustable platform depending on the conditions and requirements as needed. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of the curb forming apparatus of the invention; 
     FIG. 2 is a top plan schematic view of the curb forming apparatus of the invention; 
     FIG. 3 is a rear elevational view of an adjustable rear wheel and slope compensation assemblies; 
     FIG. 4 is a partial front elevational view of the adjustable front wheel support assembly with portions broken away and in broken lines; 
     FIG. 5 is the reverse side elevational view of the curb forming apparatus generally illustrated in FIG. 1; 
     FIG. 6 is an enlarged partial sectional view of the front wheel support assembly interconnection to the curb forming apparatus; 
     FIG. 7 is an enlarged partial cross-sectional top plan view of the assembly shown in FIG. 6; 
     FIG. 8 is an enlarged cross-sectional view of the rear wheel adjustable support assembly; 
     FIG. 9 is an enlarged rear elevational view of the adjustable rear wheel support assembly with portions broken away; 
     FIG. 10 is a side illustrative view of the auger extrusion module and hopper of the preferred embodiment; 
     FIG. 11 is an end elevational view of the auger extrusion modular with portions shown in cross-section; 
     FIG. 12 is an end illustrative view of an alternate multiple auger extrusion module and resultant curb profile; 
     FIG. 13 is an end illustrative view of a second alternate multiple auger extrusion module and the resultant end curb profile; 
     FIG. 14 is an end illustrative view of a third alternate multiple auger extrusion module and end curb profile; 
     FIG. 15 is a side illustrative view of a slip form curb module for insertation into the apparatus of the invention; 
     FIG. 16 is a side elevational view of an alternate form of the curb forming apparatus for use with a removable transfer feed module not shown; 
     FIG.  17 ,is a top plan modified schematic view of the curb forming machine as seen in FIG. 16 with a removable transfer and feed module positioned within; 
     FIG. 18 is a side elevational view of a transfer and convey module frame for the curb forming apparatus as seen in FIGS. 16 and 17; 
     FIG. 19 is an end elevational view of the transfer and conveyor module frame as seen in FIG. 18; 
     FIG. 20 is a side elevational view of the transportation and conveyor module frame with a conveyor assembly positioned within; and 
     FIG. 21 is a top plan view of the transfer and conveying mounting frame as set forth in FIG. 20 of the drawings. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2 of the drawings, a curb forming apparatus  10  can be seen comprising a main support frame  11  with a front power drive wheel and steering assembly  12  and a pair of movable rear wheel assemblies  13 A and  13 B. The main support frame  11  has an engine compartment  14  near the front power drive wheel and steering assembly  12  and a modular insert receiving opening at  15  midway between the respective front power drive wheel steering assembly  12  and rear wheel assemblies  13 A and  13 B. 
     Referring now to FIGS. 1,  4 ,  5 , and  6  of the drawings, the front power drive wheel and steering assembly  12  can be seen having a wheel mounting frame  16 , a steering handle extension and control input assembly  17  extending therefrom. 
     A telescopically extensible wheel height adjustment and support column  18  extends vertically from the wheel-mounting frame  16  having an outer support casing  18 A and an inner extensible wheel support member  18 B. A hydraulic piston cylinder assembly  19  is secured between the respective support casing  18 A and the inner extensible wheel support member  18 D. An hydraulic drive motor  20  shown in dotted lines is interconnected to drive a pair of front drive wheels  21 , rotatably positioned on the wheel support  21 A, will be well understood by those skilled in the art. The drive wheel and steering assembly  12  is in turn movably secured to the main support frame  11  by a horizontally adjustable front slider assembly  22 , best seen in FIGS. 4,  6  and  7  of the drawings. The slider assembly  22  is secured to the telescopically extensible support tubular column  18  by a guide bracket  23  with fasteners F. The guide bracket  23  is slideably disposed between a pair of parallel longitudinally spaced tubular tracks  24  and  25  and secured to the main support frame  11  to allow for horizontal movement of the steering assembly as indicated by arrows in FIG. 4. A locking clamp  26  slidably engages the respective tracks  24  and  25  from within the main support frame  11  so as to selectively lock the drive wheel and steering essembly  12  to the frame  11 . A plurality of synthetic resin bearing surface inserts  27  are interengaged between the respective bearing surfaces of the tubular tracks  24  and  25 , guide bracket  23  and slider clamp  26 . Locking bolts  28  extend from and are secured to the slider clamp  26  through the guide bracket  23 . It will be evident from the above description that by tightening the bolts  28  the drive wheel and steering assembly  12  can be selectively secured to the main support frame  11  after it has been repositioned thereon. 
     Referring now to FIGS. 3,  8 , and  9  of the drawings, the rear wheel assemblies  13 A and  13 B can be seen, each having a telescopically adjustable support tube assembly  29  from which extends a wheel bearing support assembly  30  and attached wheel  30 A. The adjustable support tube assembly  29  has an outer tubular member  29 A and an inner support extensible portion  29 B which are interengaged by hydraulic piston and cylinder assembly  31  so as to extend the inner support portion  29 B and the wheel bearing support assembly  30  in relation thereto. The support tube assembly  29  has a secondary slider bracket  33  secured thereto which is slideably engaged on a pair of vertically spaced parallel tubular tracks  34  and  35  secured to a primary slider bracket  36 . A secondary slider clamp  37  is positioned within a guide channel portion  38  of the primary slider bracket  36 , best seen in FIG. 8 of the drawings. A secondary lock bolt  39  extends from the secondary slider clamp  37  through the secondary slider bracket  33  so as to selectively lock the support tube  29  against the tracks  34  and  35 . The primary slider bracket  36  is selectively positioned on a pair of primary parallel vertically spaced tubular tracks  40 A and  40 B extending from the main support frame  11 . A primary slider clamp  41  is movably positioned from within the main support frame  11  so as to be engaged against the tubular tracks  40 A and  40 B. Primary locking bolts  42  extend from the primary slider clamp  41  and through oppositely disposed flange fitting  43  on the primary slider bracket  36 . It will thus be seen that each of the rear wheel assemblies  13 A and  13 B are horizontally adjustable on and beyond the main support frame  11  by the primary and secondary slider brackets on their respective tubular guide track pairs  33  and  34  and  40 A and  40 B as hereinbefore described and as best illustrated in FIGS. 3 and 8 of the drawings. 
     By repositioning the rear wheel assemblies  13 A and  13 B different curb forms can be used that are of a larger transverse cross-sectional end curb form as will be discussed in greater detail hereinafter. 
     Referring now to FIGS. 1 and 2 of the drawings, the module insert opening  15  in the main support frame  11  can be seen in which a number of curb forming modules can be easily and rapidly installed. A curb forming auger extrusion module assembly  44  best seen in FIGS. 1 and 10 of the drawings has a material feed reservoir  45  that is registerable within the insert opening  15 . An auger extrusion screw flight  46  is shown being rotatably positioned within a screw housing  47  having an open input area  47 A that is in communication with the feed reservoir  45  and a closed compression area  47 B which in turn is in communication with an extrusion curb form  48  in this example. The extrusion screw flight  46  within the closed compression area  47 B has incrementally decreased flight spacing for increased flights at  46 B which imparts material compression as it passes therethrough. A hydraulic motor  49  drives a flexible coupling  50  and interconnected ball bearing assemblies for an auger shaft  51  of the extrusion screw flight  46  as will be well understood by those skilled in the art. A supply hopper  52  for the curb forming auger assembly  44  is positioned to receive and direct concrete material (not shown) into the material feed reservoir  45  as hereinbefore described. Thus the extrusion curb form  48  will form a curb configuration  53  directly on the surface S as the curb forming apparatus  10  of the invention travels along the surface S. 
     Referring now to FIGS.  12 , 13  and  14 , alternate curb forming auger drive module configurations  44 A,  44 B and  44 C can be seen wherein multiple extrusion auger assemblies are mounted on a feed reservoir  42 ′ with different curb extrusion forms  52 A,  52 B and  52 C illustrated having various cross-sectional configurations. It will be seen that the multiple auger assemblies  44 A,  44 B and  44 C illustrated can be mounted in relationships such as side by side illustrated in FIG. 12 or vertically staggered, illustrated in FIGS. 13 and 14 to achieve the required extrusion output of material of the auger assembly modules in relationship to the cross-sectional curb forms  52 A,  52 B and  52 C to be formed. 
     Referring now to FIG. 15 of the drawings, an example of a slip form curb module  64  is illustrated having a supply hopper  52  with a feed bin  66  and a slip curb form  67 . A vibrator device  68  is typically used within the feed bin  66  to facilitate the transfer of creatious material into the slip form curb module  67  and the formation of a finished curb  69  shown in broken lines. 
     The use of the slip form curb module  64  is dependent on a number of ancillary factors determined by the user and site conditions or as a matter of choice in certain applications. 
     During use to compensate for varying surface (S) conditions, the curb forming apparatus  10  of the invention has grade and slope activation sensors as seen in FIGS. 1-5 of the drawings so as to compensate for variations in the surface S as the apparatus of the invention transverses same. 
     Pairs of sonar sensors  53 A and  53 B are positioned on respective mounting bars  54  secured longitudinally to the either side of the support frame  11 . In this example, the sonar sensors  53 A and  53 B are aligned to target respective pairs of surface engagement skids rails  56  that are secured to extensible jack assemblies  57  on each corner of the main support frame  11 . Each of the jack assemblies  57  has a housing  58  with a tubular jack element  59  therein that can be extended and incrementally locked in position by pins  60  extending through aligned longitudinally spaced apertures within the respective housing and jack element  58  and  59  respectively. The skid rails  56  have sonar target reflectors  61  that are used by the respective sonars sensors  53 A and  53 B. As the skid rails  56  freely follow the surface S. The sonar sensors calculate the change in relative distance and activate the appropriate hydraulic cylinders assemblies  31  in the respective wheel assemblies to adjust and maintain the pre-programmed elevational requirements of the curb to be formed. Alternately, the sonar sensors  53 A and  53 B can use a string guideline  62 ′ in place of the skid rails  56  as the guide target. The string guideline  62 ′ would typically be secured to the grade surface by nails to accommodate certain situations that may preclude the use of the skid rails  56  as would be evaluated in the field, alternately a string line  62  can be used mounted between posts  62 A. Additionally, a slope sensor  63  is mounted on the rear wheel assembly  13 A and will adjust the height of the wheel assemblies  13 A or  13 B to the desired slope i.e. the transverse relationship of the surface S maintaining the pre-determined slope indicated by the apparatus as it travels along its designated path as best seen in FIG. 3 of the drawings. The skid rails  56  can also be used to support the apparatus of the invention for repositioning the respective wheel assemblies by extending and locking the jack stands and retracting the wheel assemblies as needed. 
     An alternate grade and slope sensing system can be used as illustrated in FIG. 1 of the drawings in which each of the adjustable wheel assemblies has a laser receiver  70  on a sensor-mounting fixture  71  extending from and secured to the respective wheel support tubes. The laser receivers  70  can determine the relative position of an impinging laser beam B from a surveyor&#39;s laser as best seen in FIG. 1 of the drawings. 
     Referring now to FIGS. 16 and 17 of the drawings, an alternate form of a curb forming apparatus  80  is illustrated, in which a modified main support frame  81  can be seen having a center section of the main support frame  81  and a pair of bridge frame elements  83  and  84  extending in spaced vertical relation thereacross maintaining the machine&#39;s integrity. The alternate curb forming apparatus  80  thus has defined a large access receiving area  85  having a pair of parallel oppositely disposed guide tracks  86  and  87  as seen in FIG. 16 of the drawings. 
     A material handling box  88  can be seen in FIGS. 17,  18 ,  19  and  20  having oppositely disposed side walls  89 A and  89 B, interconnecting end walls  90  and  91  ad integral bottom portion  92 . The respective sidewalls  89 A and  89 B have a longitudinally extending guide channels  93  and  94  thereon. The guide channels  93  and  94  are registerable on respective guide tracks  86  and  87  so as to allow the material handling box  88  to be slidably positioned within the access receiving area from either side of the main support frame  81 . The respective sidewalls  89 A and  89 B and end wall  91  define a bottom recess portion  94  therebetween inwardly from the respective end wall  91 . The bottom  92  has a material of dispensing opening at  95  that extends transversely between the sidewalls  89 A and  89 B and inwardly of the respective end wall  91 . An extension collar  96  extends about the opening  95  as will be best seen in figure 18 of the drawings. 
     Each of the sidewalls  89 A and  89 B have a plurality of spaced parallel pairs of elongated slots  97  in two positioning groups at  98  and  99  respectively. 
     Referring now to FIGS. 17,  20  and  21  of the drawings, a mobile conveyor assembly  100  can be seen having a support frame  101  with an upstanding material receiving hopper  102  at one end thereof. A powered conveyor belt  103  is positioned within the support frame  101  having a plurality of belt engagement rollers  104  with an end return and drive roller assemblies  106  and  105  respectively. The drive roller  105  is driven by a hydraulic motor  107  as will be well understood by those skilled in the art. 
     Wheel assembly  108  extends from the hopper and of the conveyor assembly  100  and allows for same to be removed and transported as an independent unit. The conveyor belt assembly  100  is adjustably positioned within the material handling box  88  by a pair of independently positioned cross-support channels  110  and  111  that are registerable within respective oppositely disposed pairs of slots  97 , best seen in FIG.  20  and in broken lines in FIG.  21 . It will be evident that by repositioning the cross support channels  110  and  111  that different elevational positions of the conveyor assembly  100  can be achieved within the material handling box  88 . 
     A mounting pin  112  and swivel fitting  113  in broken lines in FIG. 20 extends from the cross support channel  111  and allows a support integration with a portion of the conveyor assembly  100  so as to be selectively positioned as hereinbefore described. 
     It will be evident that the conveyor assembly  100  once positioned within the material handling box  88  which has been inserted within the access receiving area  85  that the hopper  102  of the belt assembly  100  will extend out beyond the curb forming apparatus  80  aligned for ease of access on either side of the device. 
     Additionally, it will be evident that the receiving hopper  102  of the belt assembly  100  is substantially lower relative to the open top portion of the material receiving box  88  and thus is easier to access during use from a materials supply mixing truck (not shown) and heretofore possible in the primary form of the invention. The alternate curb forming apparatus  80  of the invention will allow curb extrusion or slip forming beyond the frame “footprint” as illustrated in broken lines in FIG. 17 of the drawings. 
     Referring back to FIG. 1 of the drawings, it will be seen that the supply hopper  52  is removably secured from the main support frame  11  by mounting brackets  52 A and is independent of the respective insert curb modules as noted above. 
     The steering handle extension and control input assembly  17  extending from the drive wheel assembly  12  has controls for the apparatus  10  of the invention in which the drive wheel assembly  12  can be pivoted so as to steer the apparatus  10  along its desired course and control its effective speed relative to the output of the curb forming modules positioned within. 
     In operation, an internal combustion engine, within the engine compartment  14  drives hydraulic pumps (not shown) therein which supply hydraulic fluid under pressure to the respective adjustable wheel assemblies, curb forming module inserts and hydraulic motor  20  of the steering and wheel assembly  12  as will be well understood by those skilled in the art. 
     From the foregoing, it will be appreciated that the present curb forming apparatus of the invention enables the production of a curb along a road bed surface S which can utilize a number of modular curb forming inserts of either the power auger extension or slip form type depending on the application desired along with precise control of grade end slope of the apparatus and the placement of the curb on said surface S during its operation. It will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention.

Summary:
An apparatus for continuously shaping and extruding a longitudinally extending curb of moldable material. The device provides a self-contained and self-powered platform for modular curb forming inserts of multiple disciplines including auger extrusion and vibratory slip form. Moldable material is supplied to a feed hopper for the modular auger/slip form inserts that creates and dispenses a shaped curb bed. Leveling sensors and guides compensate for irregular surface gradients maintaining the orientation of the formed curb shape.