Patent Publication Number: US-7909534-B1

Title: Apparatus and method for endgate with angle adjustment

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to screed assemblies adapted to apply hot mix asphalt to surfaces, and particularly to screed assemblies having endgates. 
     BACKGROUND AND DESCRIPTION OF THE PRIOR ART 
     It is known to use endgates in connection with screed assemblies adapted to apply hot mix asphalt to surfaces such as roadways, parking lots and the like. However, conventional endgates suffer from one or more disadvantages. For example, conventional endgates include a plurality of independent adjustment means and a plurality of independent means for applying force to the wear shoe. As a result, adjustment of conventional endgates is difficult and time-consuming, and each of the plurality of independent means for applying force to the wear shoe may experience unequal loads. In addition, the means for applying force to the wear shoe in conventional endgates do not remain perpendicular to the wear shoe of the endgate when the wear shoe is disposed at an angle. Consequently, conventional endgates do not maintain optimal surface contact with the hot mix asphalt applied by the screed assembly and they do not maintain uniform pressure on the hot mix asphalt. 
     It would be desirable, therefore, if an apparatus and method for an endgate with angle adjustment could be provided that would result in easier, less time-consuming adjustments. It would also be desirable if such an apparatus and method could be provided such that each of the means for applying force to the wear shoe would apply an equal load to the wear shoe. It would be further desirable if such an apparatus and method could be provided that would maintain each of the means for applying force to the wear shoe substantially perpendicular to the wear shoe when the wear shoe is disposed at an angle. It would be still further desirable if such an apparatus and method could be provided that would maintain optimal surface contact with the hot mix asphalt applied by the screed assembly and maintain uniform pressure on the hot mix asphalt. 
     ADVANTAGES OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
     Accordingly, it is an advantage of the preferred embodiments of the invention claimed herein to provide an apparatus and method for an endgate with angle adjustment that results in easier, less time-consuming adjustments. It is also an advantage of the preferred embodiments of the invention to provide an endgate with angle adjustment in which each of the means for applying force to the wear shoe or other pavement contacting surface applies an equal load to the wear shoe or other pavement contacting surface. It is a further advantage of the preferred embodiments of the invention to provide an endgate with angle adjustment that maintains each of the means for applying force to the pavement contacting surface substantially perpendicular to the pavement contacting surface of the endgate when the pavement contacting surface is disposed at an angle. It is a still further advantage of the preferred embodiments of the invention to provide an endgate with angle adjustment that maintains optimal surface contact with the hot mix asphalt applied by the screed assembly and maintains uniform pressure on the hot mix asphalt. 
     Additional advantages of the preferred embodiments of the invention will become apparent from an examination of the drawings and the ensuing description. 
     SUMMARY OF THE INVENTION 
     The invention comprises an endgate adapted to be attached to a screed assembly. The preferred endgate comprises a mounting bracket that is adapted to be attached to the screed assembly, a pivoting plate that is adapted to be pivotally attached to the mounting bracket, and a sliding plate that is adapted to be pivotally moved with the pivoting plate. The preferred endgate also includes a pavement contacting surface that is adapted to be pivotally moved with the pivoting plate, a support that is adapted to be pivotally moved with the pivoting plate, and a means for applying force to the pavement contacting surface that is disposed between the support and the sliding plate. The preferred endgate further includes a first adjustment means that is adapted to adjust the amount of force applied by the means for applying force to the pavement contacting surface and a second adjustment means that is adapted to adjust the angle of the pavement contacting surface. 
     In the preferred embodiments of the endgate, the sliding plate includes a flange, the pavement contacting surface is a wear shoe, the means for applying force to the pavement contacting surface comprises a plurality of springs that are biased between the support and the flange, and the first adjustment means and the second adjustment means are jacks. Also in the preferred embodiments of the endgate, the pivoting plate, the support, the means for applying force to the pavement contacting surface and the pavement contacting surface remain in a substantially fixed disposition relative to each other when the pavement contacting surface is pivotally moved. In another preferred embodiment, each of the plurality of springs is maintained in a substantially perpendicular disposition relative to the pavement contacting surface when the pavement contacting surface is pivotally moved. Further, in a preferred embodiment of the endgate, each of the plurality of springs applies a substantially equal amount of force to the pavement contacting surface. 
     The invention also comprises a method for an endgate with angle adjustment that is adapted to be attached to a screed assembly. The preferred method comprises providing an endgate including a mounting bracket that is adapted to be attached to the screed assembly, a pivoting plate that is adapted to be pivotally attached to the mounting bracket, and a sliding plate that is adapted to be pivotally moved with the pivoting plate. The preferred endgate also includes a pavement contacting surface that is adapted to be pivotally moved with the pivoting plate, a support that is adapted to be pivotally moved with the pivoting plate, and a means for applying force to the pavement contacting surface that is disposed between the support and the sliding plate. The preferred endgate further includes a first adjustment means that is adapted to adjust the amount of force applied by the means for applying force to the pavement contacting surface and a second adjustment means that is adapted to adjust the angle of the pavement contacting surface. The method further comprises adjusting the angle of the pavement contacting surface and adjusting the amount of force applied to the means for applying force to the pavement contacting surface. 
     In the preferred embodiments of the method, the pivoting plate, the support, the means for applying force to the pavement contacting surface and the pavement contacting surface remain in a substantially fixed disposition relative to each other when the pavement contacting surface is pivotally moved. Also in the preferred embodiments of the method, the means for applying force to the pavement contacting surface is maintained in a substantially perpendicular disposition relative to the pavement contacting surface when the pavement contacting surface is pivotally moved, and the sliding plate is adapted to be slidingly moved relative to the pivoting plate in a direction substantially perpendicular to the pavement contacting surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The presently preferred embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
         FIG. 1  is a perspective view of an exemplary screed including the preferred endgates with angle adjustment in accordance with the present invention. 
         FIG. 2  is a front view of the preferred endgate with angle adjustment illustrated in  FIG. 1 . 
         FIG. 3  is a perspective view of the preferred endgate with angle adjustment illustrated in  FIGS. 1-2 . 
         FIG. 4  is a right side view of the preferred endgate with angle adjustment illustrated in  FIGS. 1-3 . 
         FIG. 5  is a front view of the preferred endgate with angle adjustment illustrated in  FIGS. 1-4  showing the wear shoe disposed at an angle relative to the mounting bracket. 
         FIG. 6  is a perspective view of the preferred endgate with angle adjustment illustrated in  FIGS. 1-5  showing the wear shoe disposed at angle relative to the mounting bracket. 
         FIG. 7  is a right side view of the preferred endgate with angle adjustment illustrated in  FIGS. 1-6  showing the wear shoe disposed at an angle relative to the mounting bracket. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
     Referring now to the drawings, the preferred embodiment of the endgate with angle adjustment is illustrated by  FIGS. 1 through 7 . Referring to  FIG. 1 , a perspective view of an exemplary screed including the preferred endgate in accordance with the present invention is illustrated. As shown in  FIG. 1 , the preferred endgate is designated generally by reference numeral  20 . The preferred endgate  20  is adapted to be attached to exemplary screed  22  which is part of a screed assembly. More particularly, preferred endgate  20  is adapted to be attached to the outer, distal ends of a main screed or a screed extension to prevent the outward movement of hot mix asphalt applied by a screed assembly beyond the width of the main screed or any screed extensions. The preferred endgate  20  is also adapted to provide a finished edge to the hot mix asphalt applied by a screed assembly. It is contemplated within the scope of the invention that the preferred endgate  20  may be removably or fixedly connected to a screed assembly by any suitable means. 
     Referring now to  FIG. 2 , a front view of preferred endgate  20  is illustrated. As shown in  FIG. 2 , the preferred endgate  20  is attached to a screed such as exemplary screed  22  by mounting bracket  24 . The preferred mounting bracket  24  includes a plurality of holes  26  adapted to receive fasteners such as bolts or rivets, but it is contemplated within the scope of the invention that the mounting bracket may include slots or other suitable means for attaching the endgate to a screed assembly. It is also contemplated within the scope of the invention that the mounting bracket may be attached to a screed assembly by weldment, adhesives and the like. Further, while  FIG. 2  illustrates the preferred configuration of the mounting bracket, it is contemplated within the scope of the invention that the mounting bracket may be any suitable configuration adapted to attach the endgate to a screed assembly. 
     Referring still to  FIG. 2 , the preferred endgate  20  includes pivoting plate  30 . The preferred pivoting plate  30  is pivotally attached to mounting bracket  24  at pivot point  32 . While  FIG. 2  illustrates the preferred configuration and arrangement of pivoting plate  30 , it is contemplated within the scope of the invention that the pivoting plate may be of any suitable configuration and arrangement adapted to pivotally move relative to the mounting bracket. As shown in  FIG. 2 , a pavement contacting surface such as preferred wear shoe  40  is disposed near the bottom of the preferred pivoting plate  30 . The preferred wear shoe  40  is adapted to be pivotally moved with pivoting plate  30 . In addition, the preferred wear shoe  40  is adapted to contact the paving surface. While  FIG. 2  illustrates the preferred configuration and arrangement of the pavement contacting surface, it is contemplated within the scope of the invention that the pavement contacting surface may be of any suitable configuration and arrangement. It is further contemplated within the scope of the invention that the pavement contacting surface may be an integral component of the endgate or a contiguous part of the pivoting plate. It is still further contemplated within the scope of the invention that the pavement contacting surface may be heated and/or vibrated using any suitable means. 
     Referring still to  FIG. 2 , the preferred endgate  20  includes a support such as the preferred pair of spring supports  50 . Each of the preferred pair of spring supports  50  is mounted on pivoting plate  30 . Further, each of the preferred spring supports  50  is adapted to be pivotally moved with the pivoting plate and provide support to one of the means for applying force to the pavement contacting surface such as the preferred plurality of springs  52 . While  FIG. 2  illustrates a pair of spring supports, it is contemplated within the scope of the invention that more or fewer than two supports may be provided. It is also contemplated within the scope of the invention that the support(s) may be of any suitable configuration and arrangement adapted to pivotally move with the pivoting plate and provide support for the means for applying force to the pavement contacting surface. Each of the preferred plurality of springs  52  is adapted to apply a substantially equal amount of force to wear shoe  40 . It is contemplated within the scope of the invention, however, that any suitable device, mechanism, assembly or combination thereof may be used to apply force to the pavement contacting surface such as hydraulic actuators, pneumatic actuators, electric actuators, torsion springs, leaf springs and the like. 
     Still referring to  FIG. 2 , the preferred endgate  20  includes a sliding plate such as the preferred spring plate  60 . The preferred spring plate  60  is adapted to be pivotally moved with pivoting plate  30  and slidingly moved relative to the pivoting plate. As shown in  FIG. 2 , the preferred spring plate  60  includes a pair of slots  62  adapted to permit the spring plate to slidingly move relative to pivoting plate  30 . The preferred spring place  60  is adapted to move in a direction substantially perpendicular to the pavement contacting surface such as the preferred wear shoe  40 . It is contemplated within the scope of the invention, however, that the spring plate may include more or fewer than two slots or any other suitable means for permitting the spring plate to slidingly move relative to the pivoting plate. The preferred spring plate  60  also includes flange  64 . The preferred flange  64  is disposed near the top of spring plate  60  and is adapted to contact an end of each of the plurality of springs  52 . As a result, each of the preferred plurality of springs  52  is biased between one of the preferred pair of spring supports  50  and the preferred flange  64  of spring plate  60 . In addition, the preferred flange  64  is adapted to move relative to pivoting plate  30  in a direction substantially perpendicular to the pavement contacting surface such as the preferred wear shoe  40 . It is contemplated within the scope of the invention, however, that any suitable structure, device, mechanism, assembly or combination thereof may be used to bear against an end of the means for applying force to the pavement contacting surface. As shown in  FIG. 2 , the preferred springs  52  are disposed around rods  66 . The preferred rods  66  extend from the preferred pair of spring supports  50  to the preferred flange  64  and include a fastener such as nuts  68  on each end. It is further contemplated within the scope of the invention that any suitable device, mechanism, assembly or combination thereof may be used to maintain the disposition of the means for applying force to the pavement contacting surface. 
     Still referring to  FIG. 2 , the preferred endgate  20  includes a first adjustment means such as the preferred first jack  70  and a second adjustment means such as the preferred second jack  72 . The preferred first jack  70  is adapted to adjust the amount of force applied to the means for applying force to the pavement contacting surface such as the preferred plurality of springs  52 . As shown in  FIG. 2 , the preferred first jack  70  includes first jack first end  74  which is mounted to spring plate  60  and first jack second end  76  which is mounted to pivoting plate  30 . The preferred second jack  72  is adapted to adjust the angle of the pavement contacting surface such as preferred wear shoe  40 . The preferred second jack  72  includes second jack first end  78  which is mounted to mounting bracket  24  and second jack second end  80  which is mounted to pivoting plate  30 . While  FIG. 2  illustrates the preferred configuration and arrangement of the first jack and the second jack, it is contemplated within the scope of the invention that the first jack and the second jack may by of any suitable configuration and arrangement. It is also contemplated within the scope of the invention that any suitable device, mechanism, assembly or combination thereof adapted to adjust the amount of force applied to the means for applying force to the pavement contacting surface and/or adjust the angle of the pivoting plate and/or pavement contacting surface may be used such as electric actuators, hydraulic actuators, pneumatic actuators, hand cranks and the like. 
     Referring now to  FIG. 3 , a perspective view of preferred endgate  20  is illustrated. As shown in  FIG. 3 , the preferred endgate  20  includes mounting bracket  24 , holes  26 , pivoting plate  30 , wear shoe  40 , spring supports  50 , springs  52 , spring plate  60 , slots  62 , flange  64 , nuts  68 , first jack  70  and second jack  72 . 
     Referring now to  FIG. 4 , a right side view of preferred endgate  20  is illustrated. As shown in  FIG. 4 , the preferred endgate  20  includes mounting bracket  24 , pivoting plate  30 , wear shoe  40 , spring support  50 , spring  52 , spring plate  60 , flange  64 , rod  66 , nut  68 , first jack  70  and second jack  72 . 
     Referring now to  FIG. 5 , a front view of the preferred endgate  20  is illustrated. More particularly, the preferred endgate  20  is illustrated with the wear shoe disposed at an angle relative to the mounting bracket. As shown in  FIG. 5 , each of the pair of preferred springs  52  is maintained in a substantially perpendicular disposition relative to wear shoe  40  when pivoting plate  30 , and thus wear shoe  40 , is pivotally moved. As a result, each of the pair of preferred springs  52  applies a substantially equal amount of force. Preferably, pivoting plate  30 , spring supports  50 , springs  52  and wear shoe  40  remain in a substantially fixed disposition relative to each other when pivoting plate  30 , and thus wear shoe  40 , is pivotally moved. 
     Referring now to  FIG. 6 , a perspective view of the preferred endgate  20  is illustrated. More particularly, preferred endgate  20  is illustrated with the wear shoe disposed at angle relative to the mounting bracket. As shown in  FIG. 6 , the preferred endgate  20  includes mounting bracket  24 , holes  26 , pivoting plate  30 , wear shoe  40 , spring supports  50 , springs  52 , spring plate  60 , slots  62 , flange  64 , nuts  68 , first jack  70  and second jack  72 . 
     Referring now to  FIG. 7 , a right side view of the preferred endgate  20  is illustrated. More particularly, preferred endgate  20  is illustrated with the wear shoe disposed at an angle relative to the mounting bracket. The preferred endgate  20  includes mounting bracket  24 , pivoting plate  30 , wear shoe  40 , spring support  50 , spring  52 , spring plate  60 , flange  64 , rod  66 , nut  68 , first jack  70  and second jack  72 . 
     The invention further comprises a method for an endgate with angle adjustment that is adapted to be attached to a screed assembly. The preferred method includes providing an endgate comprising a mounting bracket that is adapted to be attached to the screed assembly. The preferred endgate with angle adjustment also includes a pivoting plate that is pivotally attached to the mounting bracket, a sliding plate that is adapted to be pivotally moved with the pivoting plate, and a pavement contacting surface that is adapted to be pivotally moved with the pivoting plate. The preferred endgate further includes a support that is adapted to be pivotally moved with the pivoting plate, a means for applying force to the pavement contacting surface which is disposed between the support and the sliding plate, a first adjustment means that is adapted to adjust the amount of force applied by the means for applying force to the pavement contacting surface, and a second adjustment means that is adapted to adjust the angle of the pavement contacting surface. The preferred method also includes adjusting the angle of the pavement contacting surface and adjusting the amount of force applied to the means for applying force to the pavement contacting surface. 
     In the preferred embodiments of the method of the invention, the pivoting plate, the support, the means for applying force to the pavement contacting surface and the pavement contacting surface remain in a substantially fixed disposition relative to each other when the pavement contacting surface is pivotally moved. Also in the preferred embodiments of the method, the means for applying force to the pavement contacting surface is maintained in a substantially perpendicular disposition relative to the pavement contacting surface when the pavement contacting surface is pivotally moved. Further, in the preferred embodiments of the method, the sliding plate is adapted to be slidingly moved relative to the pivoting plate in a direction substantially perpendicular to the pavement contacting surface. 
     In operation, several advantages of the preferred embodiments of the apparatus and method of the invention are achieved. For example, the preferred embodiments of the invention claimed herein provide an endgate with angle adjustment that results in easier, less time-consuming adjustments. The preferred embodiments of the invention also provide an endgate with angle adjustment in which each of the means for applying force to the pavement contacting surface applies an equal load to the pavement contacting surface. The preferred embodiments of the invention further provide an endgate with angle adjustment that maintains each of the means for applying force to the pavement contacting surface associated with the endgate substantially perpendicular to the pavement contacting surface when the pavement contacting surface is pivotally moved. The preferred embodiments of the invention still further provide an endgate with angle adjustment that maintains optimal surface contact with the hot mix asphalt applied by the screed assembly and maintains uniform pressure on the hot mix asphalt. 
     Although this description contains many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments thereof, as well as the best mode contemplated by the inventors of carrying out the invention. The invention, as described herein, is susceptible to various modifications and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.