Abstract:
A box scraper and scarifier has a scraper box and a mid-blade mounted to the scraper box, intermediate a scarifier bar and a rear wall of the scraper box. The scarifier bar, which can be either fixed or retractable, is also mounted to the scraper box. The scarifier bar includes a plurality of chisels for scarifying the soil. Positioned near the rear wall of the scraper box may be a rear cutting blade. Three actuators mounted to the box scraper and scarifier may be used to achieve a desired cut angle for either the mid-blade or the rear blade. Further, a front drawbar assembly and a rear wheel assembly may stabilize the box scraper and scarifier during use. In one embodiment, a shackle assembly attaches the box scraper and scarifier to a skid loader or tractor.

Description:
CROSS REFERENCE TO RELATED PROVISIONAL PATENT  
       [0001]     This non-provisional application claims priority of the provisional application No. 60/533,403 filed on Dec. 29, 2003. 
     
    
     BACKGROUND  
       [0002]     Box scrapers have long been used for construction purposes to form, grade and level building sites, roadways, yards and the like. Generally, scrapers are simple boxes having a single cutting edge which removes dirt and rock as it is pulled across a cutting surface, e.g. soil. Removed dirt is accumulated in a box portion of the device. Early box scrapers were vertically-adjustable by mechanical levers, jacks and eventually hydraulics. Most scrapers utilize a single cutting edge and a single axis of elevation, adjustable by raising and lowering the rear-most section of the scraper at a single articulation point. The angle of cut is determined by the elevation of the rearward portion of the scraper. The higher the elevation, the greater the cut angle.  
         [0003]     Generally, the performance of box scrapers is limited by the degree to which the scraper bounces vertically as it is dragged over the soil. Bouncing results in uneven removal of soil caused by the blade jumping over rocks and hard-packed soil. This unwanted and previously unavoidable movement of a box scraper degrades the performance of the scraper. Further, box scrapers rock back and forth between the hitch and the rear wheels, and from side to side as they are pulled across the cutting surface.  
       SUMMARY  
       [0004]     In one embodiment, the box scraper and scarifier includes: a scraper box; a scarifier bar having a plurality of chisels to selectively engage with a cutting surface; a primary blade movably and transversely mounted in the scraper box, intermediate the scarifier bar and a rear wall of the scraper box; a wheel assembly mounted to the scraper box; and, a draw bar assembly for towing the box scraper and scarifier during operation.  
         [0005]     In other embodiments, the box scraper and scarifier may include: a strengthening bar mounted to the scraper box for minimizing flexure of the scraper box during use; a first articulation mechanism connected to the scarifier bar and the strengthening bar; and/or a second articulation mechanism connected to the wheel assembly and the rear wall of scraper box, the first and the second articulation mechanisms concertedly modifying the pitch of the scraper box during operation. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  is a perspective view of one box scraper and scarifier, according to an embodiment;  
         [0007]      FIG. 2  is a side view of a blade mount of the box scraper and scarifier, according to an embodiment;  
         [0008]      FIG. 3  is a side view of a blade mount of the box scraper and scarifier having elongated bolt holes, according to an embodiment;  
         [0009]      FIG. 4  is a perspective view of one box scraper and scarifier having a hinged wheel assembly and stabilizers, according to an embodiment; and  
         [0010]      FIG. 5  is a perspective view of one box scraper and scarifier having a shackle assembly, according to an embodiment. 
     
    
     DETAILED DESCRIPTION  
       [0011]     The present teaching is by way of example, not by limitation, and is not limited to use or application with one specific type of box scrapper and scarifier. Thus, although the instrumentalities described herein are for the convenience of explanation, shown and described with respect to exemplary embodiments, these principals may be equally applied in other types of box scrapper and scarifiers.  
         [0012]     One box scraper and scarifier is shown in  FIG. 1  and generally designated  100 . The box scraper and scarifier  100  includes a scraper box  101  having a left wall  102  and a right wall  104 , wherein the left  102  and right  104  walls are substantially opposite one another. Further, a rear wall  106  transversely interconnects the left  102  and right  104  walls.  
         [0013]     Preferably, left wall  102  and right wall  104  taper, or narrow, in a direction away from rear wall  106 . Moreover, left wall  102  and right wall  104  each have a forward section, of which section  108  of left wall  102  is exemplary. As shown in  FIG. 1 , forward section  108  tapers away from a cutting surface  110  (e.g. soil) at an angle “θ”. These forward sections, e.g. section  108 , provide for clearance between the scraper box  101  and the cutting surface  110 .  
         [0014]     A scarifier bar  112  mounts transversely between left wall  102  and right wall  104 , forward of rear wall  106 . As shown in  FIG. 1 , scarifier bar  112  includes a mounting plate  114  which is bolted or otherwise mechanically attached to right wall  104 . A similar mounting scheme is used to mount scarifier bar  112  to left wall  102 . The scarifier bar  112  mounts in close proximity to a forward or leading edge  116  of the scraper box  101 . The scarifier bar  112  includes a plurality of scarifier teeth or chisels, of which chisels  118  are exemplary. Chisels  118  are spaced an even distance apart along the length of scarifier bar  112 , between left wall  102  and right wall  104 . In one embodiment, scarifier bar  112  rotates about an axis of rotation  120 , to selectively engage and disengage the plurality of chisels  118  with the cutting surface  110 .  
         [0015]     A mid-blade  122  mounts transversely between left wall  102  and right wall  104 , and is positioned longitudinally between scarifier bar  112  and rear wall  106 . As shown, mid-blade  122  includes a mounting plate  124  which is bolted or otherwise mechanically attached to right wall  104 . A similar mounting scheme is used to mount mid-blade  122  to left wall  102 . Cross-referencing  FIGS. 1 and 2 , the bottom edge  200  ( FIG. 2 ) of mid-blade  122  is adjustable to a predetermined distance “d” below the bottom or lower edge  126  of left wall  102 , and the bottom or lower edge  128  of right wall  104 .  
         [0016]     Referring now to  FIGS. 2 and 3 , it can be seen that mid-blade  122  includes a blade portion  202  and a support bar  204  which may be formed from angled iron and inverted into an upside down “V” orientation. The blade portion  202  attaches to the forward or leading edge of the inverted “V” bar  204 . In one embodiment, mid-blade  122  vertically adjusts using a plurality of slotted bolt holes, of which bolt holes  300  and  302  in  FIG. 3  are exemplary. In particular, mounting plate  124  moves vertically, in the direction of the arrows  304  in  FIG. 3 , to adjust the position of the bottom edge  200  of mid-blade  122  relative to cutting surface  110 .  
         [0017]     As mid-blade  122  engages cutting surface  110 , mid-blade  122  removes a layer of soil, rocks and the like. The removed product is forcibly moved upward along blade portion  202  and over bar  204 . This accumulation of soil, rocks and the like imparts a downward force on mid-blade  122  as the soil, etc., passes over mid-blade  122  and accumulates in compartment  130 . This downward force stabilizes mid-blade  122  as it cuts, resulting in a smooth and consistent cut into the cutting surface  110 .  
         [0018]     As shown in  FIG. 1 , a rear blade  132  may removably mount between left wall  102  and right wall  104 . Further, rear blade  132  may mount behind mid-blade  122 , adjacent to rear wall  106 . Similar to mid-blade  122 , rear blade  132  includes a mounting plate  134  which is bolted or otherwise mechanically mounted to right wall  104 . A similar mounting scheme is used to mount rear blade  132  to left wall  102 . The rear blade  132  further removes soil and the like during operation. Also, rear blade  132  acts to compact soil into small holes and crevices created by mid-blade  122 .  
         [0019]     Still referring to  FIG. 1 , a front draw bar assembly  136  connects box scraper and scarifier  100  to a tractor or similar engine for towing during operation. The front draw bar assembly  136  comprises at least one attachment bracket, of which brackets  138  and  140  are exemplary. The attachment brackets  138 ,  140  fix the front draw bar assembly  136  to scarifier bar  112 , or to other structural components of the scraper box  101  substantially near scarifier bar  112 . When mounted to the scarifier bar  122 , the brackets  138 ,  140  allow for the rotation of scarifier bar  122  as required for operations. The front draw bar assembly  136  also includes a support frame  142 , which further includes a left vertical down support  144  and a right vertical down support  146 . The down supports  144 ,  146  interface with the attachment brackets  138 , 140 . A horizontal stabilizer  148  interconnects left support  144  and right support  146 . Horizontal stabilizer  148  may be vertically aligned with, and substantially parallel to, scarifier bar  112 .  
         [0020]     A draw bar  150  removably attaches to horizontal stabilizer  148 . The draw bar  150  extends generally forward of support frame  142 . Draw bar  150  may extend forward of support frame  142  a sufficient distance to allow clearance of the towing vehicle during tight turn maneuvers. As shown in  FIG. 1 , draw bar  150  terminates in a hitch assembly  152 .  
         [0021]     The box scraper and scarifier  100  may also include a strengthening bar  154  mounted transversely between left wall  102  and right wall  104 , adjacent to and above mid-blade  122 . The strengthening bar  154  helps to minimize or eliminate flex or torque of the scraper box  101  during operation. The strengthening bar  154  is, for example, made of steel tubing and may rigidly mount to both walls  102 ,  104  of scraper box  101 .  
         [0022]     As further shown in  FIG. 1 , a hydraulic actuator  156  mounts to strengthening bar  154  and horizontal stabilizer  148  of support frame  142 . Actuation of hydraulic actuator  156  operatively lowers or raises the scraper box  101 , relative to cutting surface  110 . This hydraulic actuator  156  constitutes the first articulation mechanism for the box scraper and scarifier  100 . Raising and lowering strengthening bar  154  using hydraulic actuator  156  positions the mid-blade  122  to function as a cutting blade (in substantial contact with the cutting surface  110 ) or to function as a screed (in a position slightly removed from the cutting surface  110 ).  
         [0023]     Continuing with  FIG. 1 , a rear wheel assembly  158  attaches to an outer surface  160  of rear wall  106 . A frame  159  of the rear wheel assembly  158  includes a left wheel bar  162  pivotally attached to the outer surface  160  by an attachment bracket  164 . The left wheel bar  162  is substantially parallel to, and spaced apart from, a right wheel bar  166 . Similar to left wheel bar  162 , right wheel bar  166  also pivotally attaches to outer surface  160  of rear wall  106  by a bracket  168 . The left wheel bar  162  and right wheel bar  166  are supported and separated by a transverse wheel bar  170 .  
         [0024]     A hydraulic actuator  172  pivotally mounts to both the transverse wheel bar  170 , and to outer surface  160  of rear wall  106 . Actuation of hydraulic actuator  172 , which may be in concert with the operation of hydraulic actuator  156 , raises and lowers that portion of scraper box  101  closest to rear wall  106 , and determines the dig angle or scraping angle of rear blade  132 . This hydraulic actuator  172  constitutes the second articulation mechanism for box scraper and scarifier  100 .  
         [0025]     A left wheel  174  attaches to left wheel bar  162 ; and a right wheel  176  attaches to right wheel bar  166 . In one embodiment, as shown in  FIG. 4 , left wheel bar  162  may include a hinged portion  400  adjacent to left wheel  174 . The hinged portion  400  may include a hinged bar  402 . Further, a hydraulic actuator  404  mounts to left wheel bar  162  and hinged bar  402 . Actuation of hydraulic actuator  404  changes the overall slope angle of the scraper box  101  and, hence, the cut angles of blades  122 ,  132 . This embodiment allows box scraper and scarifier  100  to be used for contouring the ground and cutting sloped surfaces. It is to be understood that hydraulic actuator  404  and hinged bar  402  can be positioned on either the left  162  or the right  166  wheel bar. This hydraulic actuator  404  constitutes the third articulation mechanism for box scraper and scarifier  100 .  
         [0026]     In yet another embodiment, as further shown in  FIG. 4 , rear wall  106  may include a rigid and reinforced upper section  406 , and a lower section  408  hinged to the upper section  406 . The lower section  408  opens or swings generally in the direction of rear wheel assembly  158 , and will open until contacting at least one stop, of which stops  410  and  412  are exemplary. During normal scraping operations, lower section  408  may be fastened so as to prevent the swinging or opening of lower section  408 . More specifically, lower section  408  may be fastened at each of the left  102  and right  104  walls. In one embodiment, lower section  408  includes a left  414  and a right  416  hinged section. Either one or both hinged sections  414 ,  416  of lower section  408  can be released and allowed to swing generally toward a stop  410 ,  412 . This embodiment allows work material such as dirt to pass through the compartment  130  of box scraper and scarifier  100 . If only one end  414 ,  416  of lower section  408  is released, the work material will be directionally “graded” similar to the blade of a road grader.  
         [0027]     Still another embodiment includes a left stabilizer  418  and right stabilizer  420  positioned on either side of draw bar  150 . The stabilizers  418 ,  420  removably attach to left vertical down support  144  and right vertical down support  146  respectively. A left wheel assembly  422  attaches to left stabilizer  418 , and a right wheel assembly  424  attaches to right stabilizer  420 . The stabilizers  418 ,  420  generally stabilize the box scraper and scarifier  100 , and further limit bounce of box scraper and scarifier  100  during operation.  
         [0028]     Referring now to  FIG. 5 , in one embodiment a shackle system  500  mounts to rear wall  106 . During operation of box scraper and scarifier  100 , shackle system  500  attaches to a skid loader or skid tractor, either of which is used to move the box scraper and scarifier  100  forward. The rear wheel assembly  158  and front draw bar assembly  136  are both removed from box scraper and scarifier  100  when shackle system  500  is employed. As shown, shackle system  500  includes a pair of spaced apart vertical support members,  502  and  504 , which receive and hold securely the universal mount of a skid loader. Further, rear wall  106  may include openings  506  and  508 , in proximity to the bottom of each vertical support member,  502  and  504  respectively. In this configuration, openings  506 ,  508  receive the skid loader forks prior to operation. The forks of the skid loader are positioned within openings  506 ,  508  in rear wall  106 , and box scraper and scarifier  100  is used as a front mount box scraper  100 .  
         [0029]     Changes may be made in the above methods, devices and structures without departing from the scope hereof. It should thus be noted that the matter contained in the above description and/or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense. The following claims are intended to cover all generic and specific features described herein, as well as all statements of the scope of the present method, device and structure, which, as a matter of language, might be said to fall therebetween.