Patent Abstract:
A ground scraper designed to be pulled by a tractor or the like includes a pair of parallel frame rails with a scraper blade between them and perpendicular to them. The scraper blade can lowered to a preferred depth of scraping and can be raised above the bottom of the frame for towing. Dual-wheeled trucks on the rear of the frame can be raised off the ground to allow the frame to contact the ground for scraping and can be lowered into contact with the ground, also raising the frame off the ground, for towing on roads or the like. The rear of a tongue can be raised relative to the front of the tongue to pick up the front of the ground scraper frame for transporting the ground scraper and then the rear of the tongue can be lowered relative to the front of the tongue, allowing the frame to contact the ground. The exact angle of the tongue can float up and down in order to allow towing on uneven terrain.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not Applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   SEQUENCE LISTING 
   Not applicable 
   BACKGROUND OF THE INVENTION 
   The present invention is related to an apparatus for scrapping ground to remove an upper layer of material. More particularly, the present invention is designed and adapted for removing hardened manure from animal feed lots and the like. 
   DESCRIPTION OF THE RELATED ART INCLUDING INFORMATION DISCLOSED UNDER 37 C.F.R. 1.97 AND 1.98 
   Maintenance of feed lots, for example cattle fatting pens, is the largest expense of operating a feed lot. Removal of the accumulated manure is a very substantial portion of these expenses and present removal methods are slow and labor intensive. The present invention is designed to improve productivity of manure removal and the precision the depth of scraping needed to provide the best result in cleaning feed lots. 
   When livestock, such as cattle or hogs, is confined to feed lots or pens for fattening, large amounts of manure quickly accumulate. The accumulated manure becomes compacted as the animals walk on it. With this compression, drying and summer&#39;s intense sun, the manure hardens into a very solid dense material, which must be removed from time to time to maintain the elevation of the lot relative to fences and to reduce the opportunities for diseases to flourish. Because the manure hardens to a brick-like consistency in the hot sun, removing it is a difficult and expensive. 
   The upper layers of manure harden into a material called hardpan. Below the hardpan, the manure and the underlying ground tend to remain wet or moist and there disease bacteria live and thrive. The hardpan seals most bacteria into the underlying material and protects the animals from diseases. Removing all the manure exposes the underlying contaminated material and causes foot rot in animals and may expose them to other diseases. Therefore, in removing manure from animal feed lots it is economically important to remove only a relatively thin layer, ranging from 1 inch to 1 foot, of the hardpan, leaving an upper surface that is itself hardpan. 
   Because the hardpan has a brick-like consistency, it must be broken up before it can be removed. In one common technique, a conventional plow is pulled by a tractor to break up the hardpan. Then the loosened material is loaded into a truck bed by a front loader or the like for removal. This method, however, disrupts the lowest level of material that is plowed, that is, it does not leave an unbroken pan surface at the lowest point the plow blades strike, but rather creates an unsealed new surface, leading to a plowplan, that is a bowl in which the bottom surface is disrupted and porous and the sides are compacted soil or the like. Rain converts the plow pan into a lake and the broken-up bottom surface allows the free migration of disease bacteria to the surface, causing the animals to become ill. The same disease process occurs without rain, but perhaps less vigorously. 
   Therefore, it is important to leave an unbroken solid hardpan surface behind after removal of manure from feedlots. In order to accomplish this result, it is essential to control preciously the depth of the material that is removed. It is also crucial that the outer ends of any scraping blade be physically contained so that the outer ends of the scraping blade do not rip up ground adjacent to them, which would result in broken ground. 
   Some scrapers and the like have been patented, including for example U.S. Patent Application Publication 2002/0133899, disclosing an invention by Van den Berg that was published on Sep. 26, 2002, discloses an “Unmanned Vehicle Adapted to Be Used in a Stable, Such as a Cowshed” comprising a scraper on the end of a telescopic boom that extends rearwardly from a motorized vehicle and a second manure displacing device which is located under the vehicle chassis, which rides on wheels. In one embodiment, the downward force on the scraper can be adjusted by the cylinder  12 , which applies downward force to the extension boom. This design does not provide boundary to the edges of the scraper blade, causing tearing of the ground at the outer edges of the scraper blade. The apparatus is also complex and expensive to manufacture and maintain. 
   U.S. Pat. No. 6,446,298, issued to Berg, Jr. et al. on Sep. 10, 2002, discloses a “Scraper for Animal Stalls” comprising a pair of scraper blades that have a number of depending curved plates welded to the back sides of the scraper blades mounted on a frame and pulled by the tow bar  15 . When the scraper is pulled forward, the curved plates move such that the scraper blades fall into a vertical position where the lower edges of the scraper blades contact the ground and scrape it. The curved plated terminate in a thickened cylindrical disk-shaped end which serve as cam followers along the ground. This results is a cutting depth that changes in response to different densities of the manure, in contrast to the more desired practice of removing a certain specific thickness of manure. 
   U.S. Pat. No. 6,442,921, issued to Feeley on Sep. 3, 2002, discloses a “Method of Raking with a Tractor Having a Rear Hydraulic Blade” comprising a blade, resembling a small snow plow or scraper having a concave side profile and a flat straight bottom edge. The rake fitting is an elongated channel member that is fastened to the bottom the snow plow blade and which includes a plurality of downwardly protecting teeth or tines, which serve as rake tines when the device is pulled while resting on the ground. Any type of scraping carried out with this device would result in a broken lower scraped surface, allowing bacteria in the soil to reach feedlot animals. 
   U.S. Pat. No. 6,098,320, issued to Wass on Aug. 8, 2000, discloses a “Front End Loader Attachment Including Forks and Grapple for Digging, Dislodging and Lifting Materials” comprising a grapple having a lower jaw or fork with pointed lower ends and pivoting upper jaw that can be opened or closed against the lower jaw by a hydraulic ram. The jaws and can be used to pick up, move and release objects and could be used to break up soil or the like, but would leave a broken lower surface. 
   U.S. Pat. No. 5,901,911, issued to Davis on May 11, 1999, discloses an “Apparatus and Method for Removing Caked Litter from a Poultry Facility” comprising a sifting apparatus attached to a small tractor or the like. The sifting apparatus picks up litter from the floor of a chicken coop and sifts out the clean litter, returning it to the floor, while retaining the soiled litter for use as fertilizer. A number of arms mounted on an axle rotate in the fashion of a boat&#39;s paddle-wheel and the ends contact the ground to break up and sweep up the litter for sifting and delivering the caked litter to a conveyor belt, which carries it up and deposits it into a bin. This device cannot break up hardpan or leave an unbroken surface after scraping. 
   U.S. Pat. No. 5,423,394, issued to Kendle on Jun. 13, 1995, discloses a “Three Point Hitch for Hummer Truck and Other Vehicles” comprising a base plate that presses against the bumper of the motor vehicle and is fastened thereto to provide a hitch that supports a boom, which can be raised or lowered by a hydraulic ram and may carry a blade for scrapping gravel, snow, ice, dirt, manure and the like from the ground or a floor (column 4, lines 7-12). Such a blade is not described further and is not illustrated. In any event there is no disclosure or suggestion that any scraping could be carried out to a particular desired depth. 
   U.S. Pat. No. 5,297,745, issued to Vinyard on Mar. 29, 1994, discloses a “Rear-Mounted Manure Gathering Machine and Method of Handling Manure” comprising a frame carried above the ground by wheels that can be raised or lowered by a hydraulic ram, pushing against an arm attached to a pivot point, which causes a link to the wheel to move up or down. When the wheels are raised, they do not contact the ground and the frame does. A yoke at the front of the machine is connected to a draw bar of a tractor or the like. Mounted on top of the frame is a large tank and a pickup mechanism that includes a vertically oriented set of stacked rotating vanes attached to the rear of the machine. At the bottom of the housing for the pickup mechanism is a scraper blade which contacts the ground during scraping and scrapes material into a bin, that is, a housing enclosure where augers sweep up the loosened material into the center of the width of the frame. The manure is mixed with water in an onboard tank the resulting slurry is sprayed from the tank. The scraper blade is at the very rear of the apparatus, where control of the weight on the blade is lacking and hence it is not well suited for cutting to a specific depth. 
   U.S. Pat. No. 4,711,403, issued to Gregory, Sr. et al. on Dec. 8, 1987, discloses a “Method and Apparatus for Cleaning Chicken Manure from Chicken Houses” comprising a motorized vehicle that carries a scraper blade that scraps up chicken litter and manure and coveys to a classifier shaker that separates the chicken litter from the manure and shakes the litter back onto the floor for reuse. This apparatus is designed to scrap material down to a hard floor and is not adapted for digging into the ground. 
   U.S. Pat. No. 4,044,843, issued to Holub on Aug. 30, 1977, discloses a “Tractor-Mounted Scraper” comprising a scraper blade that is attached to the front of a convention shovel bucket such as those commonly used on front-loaders, bulldozers and the like, which is attached to a tractor. A hydraulic ram can change the angle of the scraper and a second hydraulic ram can be used to press downwardly on the frame of the scraper sufficiently to pick up the rear wheels of the tractor, thereby applying more weight to the scraper. This device does not provide controlled cutting away of a specific depth of material. 
   U.S. Pat. No. 3,912,016, issued to Arnold on Oct. 14, 1975, discloses a “Hydraulically Powered Root and Soil Separating and Windrowing Apparatus” comprising spaced parallel side members that hold a plurality of rotating vanes, which are like plow disks. A scraper blade is attached at the front of the apparatus and digs into the ground. The angle of the scraper blade can be changed by adjusting the length of a control cable. This device does not provide for control of the depth of cutting or contain the ends of the blade. 
   U.S. Pat. No. 3,845,517, issued to Harris on Nov. 5, 1974, discloses a “Scraper Attachment” comprising a pair of elongated scraper blades attached to a tractor for being pulled by the tractor. The blades fold up vertically behind the tractor for transport. The device is designed for, scraping manure, for example, but cannot control the depth of the cut. An alternative embodiment includes solid plates whose bottom edges cut into the ground. This embodiment is basically like a snow plow that is pulled instead of pushed and which suffers from the same shortcoming as the preferred embodiment. 
   U.S. Pat. No. 3,458,029, issued to Allen et al. on Jul. 29, 1969, discloses a “Pit Cleaner for Animal Houses” comprising a scraper blade with flexible extensions to permit the scraper blade to be used with varying widths of scraping paths. This scraper cannot be used to cut into the ground or to cut to a specified depth. 
   U.S. Pat. No. 3,409,120, issued to Van Huis on Nov. 5, 1968, discloses a “Manure Scraper” comprising a scraper blade, which is held by a pair of abbreviated frame members, which are attached to a pair of cables for pulling the device using a tractor or the like. This device cannot be operated to cut into the f ground by a specified amount. 
   Thus there is a need for a ground scraper that can scrape ground, manure or the like to a specified depth; that leaves behind an unbroken surface; and that breaks up the scraped material into pieces that can be readily handled with other equipment; that contains the two ends of the scraper blade to prevent the two ends from breaking up adjacent ground, preserving the unbroken resulting surface adjacent to the ground scraper as well as along length of the scraper blade, rather than leaving a broken finished surface that would encourage disease in feedlot animals; and that can be travel over conventional roads in a non-scraping mode and then lowered into a scraping mode at the job site. 
   BRIEF SUMMARY OF THE INVENTION 
   Accordingly, it is a primary object of the present invention to provide a ground scraper that can scrape ground, manure or the like to a specified depth. 
   It is another object of the present invention to provide a ground scraper that leaves behind an unbroken surface and that breaks up the scraped material into pieces that can be readily handled with other equipment. 
   It is another object of the present invention to provide a ground scraper that contains the two ends of the scraper blade to prevent the two ends from breaking up adjacent ground, preserving the unbroken resulting surface adjacent to the ground scraper as well as along length of the scraper blade, rather than leaving a broken finished surface that would encourage disease in feedlot animals. 
   It is another object of the present invention to provide a ground scraper that can be travel over conventional roads in a non-scraping mode and then lowered into a scraping mode at the job site. 
   These and other objects of the present invention are achieved by providing a frame having a pair of C-channel side members extending from the front of the ground scraper to its rear, with these members connected by front and rear cross members to form a box frame, with a transversely mounted scraper blade in approximately the middle of the box frame. In use, the side rail members, but not the front or rear frame members, ride hard on the ground, held in firm contract with the ground by a number of large weights mounted on the frame, and a pair of vertically mounted double-acting hydraulic rams, with one connected to each end of the scraper blade. These rams can force the blade into the ground. The ground scraper is attached to an articulated tongue that is fastened to a tractor, which pulls it. 
   A rear carriage wheels truck can be raised to drop the frame onto the ground, or lowered to lift the frame off the ground, allowing the ground scraper to be pulled without scraping, thereby permitting it to be pulled along conventional streets or over fields until the job site is reached. The rear carriage wheels truck is raised or lowered by dedicated double-acting hydraulic rams. 
   The tractor&#39;s hydraulic power system is used to actuate and to control the double-acting hydraulic rams on the ground scraper. 
   The ground scraper according to the present invention is designed to automate the process of removing such manure from feedlots and pens. The ground scraper is a scraper, which cuts or scraps a layer of ground or the like, such as manure from the feedlot substrate, with a layer of manure being forced up and over the top of scraper blade, which breaks the scraped layer in to pieces, where it then lies lose on the ground. In this condition, the manure can readily be removed by other equipment, such as a snow plough-type blade, a front loader or the like, which deposits the manure into a truck bed or the like for removal and disposal or for further use. 
   Other objects and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, the preferred embodiment of the present invention and the best mode currently known to the inventor for carrying out his invention. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       FIG. 1  is a side view of a ground scraper according to the present invention shown attached to a farm tractor. 
       FIG. 2  is a left front isometric view of the ground scraper of  FIG. 1 . 
       FIG. 3  is a cross sectional left-hand side view of the ground scraper of  FIG. 1  shown with the carriage wheels deployed downward for pulling the ground scraper without scraping taken along lines  3 - 3  of  FIG. 2  and the outside wheel removed for clarity. 
       FIG. 4  is a cross sectional left-hand side view of the ground scraper of  FIG. 1  shown with the carriage wheels deployed upward for pulling the ground scraper to scrap the ground taken along the lines  4 - 4  of  FIG. 2  and the outside wheel removed for clarity. 
       FIG. 5  is a rear view of the ground scraper of  FIG. 1  shown with the carriage wheels deployed upward, allowing the ground scraper to be pulled along the ground and scrap the ground. 
       FIG. 6  is a rear view of the ground scraper of  FIG. 1  shown with the carriage wheels deployed downward, allowing the ground scraper to be pulled along the ground without scraping the ground. 
       FIG. 7  is an enlarged fragmentary left front isometric view as shown in  FIG. 2  with enlarged parts for clarity. 
       FIG. 8  is an enlarged fragmentary isometric view of the scraper blade assembly of the ground scraper of  FIG. 1  shown from the rear of the scraper blade assembly. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIG. 1 , the ground scraper  10  includes a box frame  12  that houses a scraper blade assembly  14  that can be lowered into a ground scraping position and raised to clear the ground or to scrape to selected depths by the double-acting scraper left-side hydraulic ram  16  and the double-acting scraper blade right-hand hydraulic ram  18  ( FIG. 2 ). As the ground scraper  10  is pulled along the ground by the tractor  20  with the ground scraper  10  in the lowered position and the scraper blade assembly  14  in a lowered position, the ground scraper  10  scrapes the top layer of ground or other material to the desired depth, breaking the scraped layer into principally large pieces that can be scooped up by front loaders or the like (not shown) and loaded into a dump truck of the like (not shown) for further handling. Right-side, right, left-hand, left and so forth are defined from the point of view of a driver sitting in the driver&#39;s seat  21  of the tractor  20 . Front is the end of the ground scraper  10  closer to the tractor  20  when the ground scraper  10  is attached to the tractor  20  as shown in  FIG. 1  and rear is the portion of the ground scraper  10  that is farthest from the tractor  20  when the ground scraper  10  is attached to the tractor  20  as shown in  FIG. 1 . 
   Still referring to  FIG. 1 , the box frame  12  includes a front end  22  with a tongue  24  attached to the front end  22  of the box frame  12 . In use the tongue  24  is connected to the tractor  20  or the like so that the tractor  20  can pull the ground scraper  10  using a conventional and appropriate hitch assembly. Hydraulic lines  26  are connected to the hydraulic power system of the tractor at their distal ends  28  and at their proximal ends  30  to various hydraulic control cylinders to raise and lower the carriage truck wheel assembly  32  and the scraping blade assembly  14 , described below. The carriage truck wheel assembly  32  is raised and lowered by the double-acting carriage truck assembly right-side hydraulic ram  34  and the double-acting carriage truck assembly left-side hydraulic ram  36  ( FIG. 2 ). When the carriage truck wheel assembly  32  is extended downward, as shown in  FIG. 1 , and the front end  22  of the box frame  12  is raised as described in connection with  FIG. 2  below, the bottom edge  38  of right-hand side frame rail  40  and the corresponding bottom edge  41  of the left-hand side frame rail  42  ( FIG. 2 ) are elevated above the ground  44  so that no scraping can be performed and the ground scraper  10  can be towed on roads or over fields to the job site, where the scraper blade assembly  15  is lowered into the scraping position at the desired depth into the soil. 
   Referring to  FIG. 2 , the box frame  12  is formed from the spaced parallel side frame rails  40 ,  42 , which are steel C-channel beams, that run from the front to the rear of the ground scraper  10 , and which are connected by the transverse front frame member  46 , which has an upper surface even with the upper surfaces of the side frame rails  40 ,  42 , but which is narrower so that it does not touch the ground and the rear transverse brace  48  fixed the top of the side frame rails  40 ,  42  perpendicular to them, preferably by welding, to complete the box frame  12 . Importantly, during scraping, no part of the front or rear of the box frame  12  contacts the ground, which is broken up into pieces by the scraper blade  118  and scraper  96 . A transverse wheel carriage member  50  (best seen in  FIG. 5 ) holds the truck assemblies  132 ,  138  of the carriage truck wheel assembly  32 . 
   Still referring to  FIG. 2 , three substantial weights are mounted on the box frame to ensure forceful contract of the side frame rails  40 ,  42  when the ground scraper is deployed in the scraping mode. An upstanding rear weight-retaining pin  52  is fixed to the box frame  12  in the middle of the rear transverse frame member  50  and a cylindrical rear weight  54  having an central aperture  56  through it is mounted on the pin  52 . The rear weight  54  weighs preferably about 680 kg (1,500 lbs)-910 kg (2,000 lbs). A left front weight  58  having a central aperture  60  is similarly mounted on the upstanding left front mounting pin  62 , which is welded to the box frame  12  and a right front weight  64  having a central aperture  66  is mounted onto the upstanding right front mounting pin  68 , which is welded to the box frame  12 . The left front weight  58  and the right front weight  64  are also preferably essentially cylindrical and the preferred weight of each normally falls within the range of about 230 kg. (500 lbs)-385 kg. (850 lbs). The amount of all the weights can be adjusted as needed to achieve a specific depth of cut. In each case, the weight must be sufficient to maintain contact between the lower edges of the side frame rails  40 ,  42  and the ground at all times during scraping. 
   Still referring to  FIG. 2 , the tongue  24  is mounted onto a tongue bracket  70  having a pair of mounting ears  72 , which is fastened to the front transverse frame member  46 . The tongue  24  includes a left tongue member  74  and a right tongue member  76  joined at their font ends and spaced apart to accommodate a rectangular tongue plate  78 , with the two tongue members  74 , forming a triangle, whose base is pivotally fastened to the tongue bracket  70  at the ears  72 , where the tongue plate  78  is fastened between the left tongue member  74  and the right tongue member  76  by the pin  77 . Intermediate of the tongue&#39;s  24  ends is fastened a reinforcing plate  80 , having an upstanding pin  82  fastened to it for receiving and retaining another weight similar to the weights  54 ,  58 ,  64 , if needed. 
   Still referring to  FIG. 2 , the distal end  83  of the tongue  24  can be pivoted up and down about the pin  77 , which is adjacent to, parallel to and in front of the transverse front frame member  46  for towing and to facilitate continuous contact between the ground  44  and the side frame rails  40 ,  42  during scraping and to prevent such contact when the ground scraper  10  is in its transport mode by operation of the double-acting tongue hydraulic ram  84 . The hydraulic ram  84  is mounted on a vertical portion of the tongue hydraulic ram mounting plate  86 , which is fastened to the box frame  12 . The piston rod  85  of the tongue hydraulic ram  84  moves the upper end of the vertical pivot arm  88 , which has a lower end pivotally connected to the front end of the tongue hydraulic ram mounting plate  86 , back and forth as controlled by the operator of the ground scraper  10 . A horizontal tongue control arm  90  is pivotally connected to an upstanding gusset  92  fastened to the tongue plate  78  at its distal end and is pivotally mounted between the upper and lower ends of the vertical pivot arm  88  at its proximal end. A long reenforcing rod  94  has one end fastened to the tongue hydraulic pate  86  at one end and to the rear transverse brace  48  at its other end to brace the double-acting hydraulic ram  84 . When the piston rod  85  of the hydraulic ram  84  is extended, the distal end of the tongue  24  is pushed downward and when the piston rod  85  is retracted, the distal end of the tongue  24  is raised. 
   Still referring to  FIG. 2 , a scraper  96  runs across the box frame  12  between the right-hand side frame rail  40  and the left-hand side frame rail  42  about half-way between the transverse front frame member  46  and the rear transverse frame member  50 . The scraper  96  is fixed to the lower end of a left-hand scraper arm  98  on its left-hand end and to the lower end of a right-hand scraper arm  100  on its right-hand end. The upper ends of the left-hand scraper arm  98  and the right-hand scraper arm  100  are fastened to a sleeve  102  mounted over a stationary axle  104 , allowing the scraper to be moved up and down. The up and down movement is controlled by operation of the double-acting scraper left-side hydraulic ram  16 , which is vertically mounted on the bracket  106  and the double-acting scraper right-side hydraulic ram  18 , which is vertically mounted on the bracket  108 . A distal end  110  of the piston rod  111  of the right-side double-acting hydraulic ram  18  is pivotally connected to the top end of a right-hand vertical force transfer plate  112 , whose lower end is fixed to the right-hand side of the scraper  96 . A distal end  114  of the piston rod  115  of the left-side double-acting hydraulic ram  16  is pivotally connected to the top end of a left-hand vertical force transfer plate  116 , whose lower end is fixed to the left-hand side of the scraper  96 . The two double-acting hydraulic rams  16 ,  18  operate in concert, with each piston rod moving up or down by the same distance and with the same force. In use the rams  16 ,  18  are preferably 60,000 lbs rams. 
   Still referring to  FIG. 2 , a scraper blade  118  is bolted to the lower edge of the scraper  96  and can be removed and sharpened or replaced. The scraper blade  118  is preferably about 2.5 m (8 feet) long, 25 cm (10 inches) wide and 1.3 cm (0.5 inches) thick. The scraper blade  118  can be pushed into the soil by any desired amount from 0 to about 20.5 cm (8 inches) and bites into the soil at an angle between about 15°-30° with the preferred angle being about 22° (the angle of attack), that its, with the lower edge  120  of the scraper blade  118  being closer to the front end  22  of the box frame  12  that the top edge  122  of the scraper blade  118 . The scraper is held in a desired position by the rams  16 ,  18 . As the scraper  116  is pushed into the soil, the angle of attack of the scraper blade  118  changes somewhat due to the pivoting motion of the scraper  96  about the axis of rotation defined by the arms  98 ,  100 , but such changes in the attack angle are insignificant so long as the scraper blade  96  remains within the stated range. 
   Still referring to  FIG. 2 , left-side hydraulic ram  36  is pivotally connected at it upper end  124  to the vertical mounting bracket  126 , whose lower end is fixed to the rear transverse brace  48  and the right-hand hydraulic ram  32  is pivotally connected at its upper end  128  to the vertical mounting bracket  130 , whose lower end is fixed to the rear transverse brace  48 . The mounting brackets  126 ,  130  provide the necessary resistence for the rams  34 ,  36  to work against. The rams  34 ,  36  operate in concert, with the piston rods both being extended or retracted by the same distances and at the same rates. 
   Still referring to  FIG. 2 , the carriage truck wheel assembly  32  includes a left-hand truck  132  having a pair of wheels and tires  134 ,  136  and a right-hand truck  138  having a pair of wheels and tires  140 ,  142  all mounted on a live axle  144 . The distal end of the piston rod  146  of the ram  36  is pivotally connected to the axle housing  148  and the right-side ram  34  is identically connected to the axle housing  148 . A left-hand swing arm  150  is pivotally connected to the rear transverse brace at one end and to the axle housing  148  at its other end. A right-hand swing arm  152  is identically connected adjacent to the right-hand side of the box frame  12 . 
   Referring to  FIG. 3 , as shown, the box frame  12  and the scraper blade  118  are lifted off the ground  44  for pulling the ground scraper  10  along the roads or to a job site. The piston rod  146  of the double-acting carriage truck assembly left-side hydraulic ram  36  is shown fully extended, as is the piston rod of the ram  34 , which lifts the box frame  12  off the ground  42 . The left-side swing arm  150  is pivotally connected to the rear transverse brace  48  at the pivot housing  154 . The lower end  156  of the left-side swing arm  150  is fixed to the left-hand truck  132  at the sleeve  158 , which is fixed to the axle housing  148  between the wheels  134 ,  136 . The top end  160  of the right-angle bracket  162  is pivotally connected to the lower end  164  of the piston rod  146  of the ram  36 , while the lower end  166  of the right angle bracket  162  is fixed to the axle housing  148  and the lower end  168  of the left side swing arm  156 . 
   Still referring to  FIG. 3 , in the over the road transport mode shown in  FIG. 3 , the scraper  96  and attached scraper blade  118  are retracted well above the ground  44  and above the lower edge of the box frame  12  by fully retracting the piston rods on the double-action scraper blade left-side hydraulic ram  16  and the double-acting scraper blade right-side hydraulic ram  18 . 
   Still referring to  FIG. 3 , the distal end  83  of the tongue  24  is lowered by extending the piston rod  85  on the double-acting hydraulic ram  84 . When the distal end  83  of the tongue  24  is connected to a fixed height hitch, as shown in  FIG. 1 , the front of the box frame  12  is raised up off the ground  44  into a transport position. When the scraper  96  and front of the box frame  12  are thus raised and the carriage truck wheel assembly  32  is lowered, thrusting the rear of the box frame  12  upward, the ground scraper is ready for transport as a trailer and can be legally and safely driven on the roads or over fields or the like to the specific job site when ground needs to be scraped. This eliminates the need for a separate trailer for transporting the ground scraper  10  to a job site. 
   Still referring to  FIG. 3 , the scraper  96  is formed from a scraper face  166  set at a downward angle with its front edge in front of its top edge and a brace member  168  fixed to it along its entire length by welding or the like at an angle of about 135° to the scraper face  166 , with a seven reenforcing gussets  168  secured by welding to both the scraper face and the brace member  168 . The scraper blade  118  is fastened adjacent to the lower edge of the scraper face  166 . This construction is shown in more detail in  FIG. 8 . Other constructions, such as a one-piece scraper are also desirable. 
   Referring to  FIG. 4 , each of the above three steps has been reversed, making the ground scraper ready for scraping. The rear wheels  132 ,  136 ,  140 ,  142  are raised out of contact with the ground  40  by fully retracting the piston rods in the rams  34 ,  36 , as indicated by the arrow  161 , causing the counterclockwise pivoting action indicated by he arrow  163 . The scraper blade  118  is forced into the ground to the desired depth by extending the piston rods on the rams  16 ,  18 , causing the downward motion shown by the downward arrow  165  and the counterclockwise pivoting action of the arms as indicated by the pivot arrow  167 . Finally, the distal end  83  of the tongue  24  is pivoted upward by retracting the piston  85  of the ram  84 , allowing the front edges of the side rails frame members  40 ,  42  of the box frame  12  to be held against the ground  44  by the weights  54 ,  64 ,  58 , while the tongue  24  can ride up and down as needed in uneven terrain. This floating movement is accomplished by allowing the connecting bolt  170  in the upstanding gusset  92  to reciprocate in the slot  172  in the horizontal tongue control arm  90  ( FIGS. 2 ,  8 ), as explained in greater detail in connection with  FIG. 8  below. In the use position, bottom edge  38  of the right-hand side frame rail  40  and the bottom edge  41  of the left-hand side frame rail  42  both contact the ground  40  throughout their lengths (unless a rough surface causes one or the other to ride on a high spot, which will soon be eliminated) and the scraper  96  is lowered into the ground  44  to the desired depth. Hydraulic fluid carrying metal pipes  174  carry hydraulic fluid and pressure to the various rams throughout the ground scraper  10  and are connected to the flexible hydraulic lines  26 . All lines may be flexible if desired, but utilizing the metal pipes  174  is more cost effective and more durable. Specific designs of the hydraulic circuits for the ground scraper  10  are considered to be within the ordinary skill in the art. 
   Referring to  FIG. 5 , the ground scraper  10  is shown in use, with the bottom edge  41  of the left-hand side frame rail  40  and the bottom edge  38  of the right-hand side frame rail  40  contacting the ground  44  and the scraper blade  118  is lowered into its ground scraping position, while the carriage truck wheel assembly  32  is raised up so that the wheels  134 ,  136 ,  140 ,  142  do not contact the ground  44 . Also visible in  FIG. 5  is the piston rod  147  of the double-acting carriage truck assembly right-side hydraulic ram  34 . 
   Referring to  FIG. 6 , the ground scraper  10  is shown in its transport position, i.e., non-scraping position, with the bottom edge  41  of the left-hand side frame rail  40  and the bottom edge  38  of the right-hand side frame rail  40  well above the ground  44  and the scraper blade  118  raised into its non-scraping position above the bottom edge  41  of the left-hand side frame rail  40  and the bottom edge  38  of the right-hand side frame rail  40 , while the carriage truck wheel assembly  32  is in its lowered position with the wheels  134 ,  136 ,  140 ,  142  in contact with the ground  44  so that the ground scraper can be towed over roads or fields to the job site. 
   Referring to  FIG. 7 , when the piston rod of the ram is extended along the direction of the arrow  180 , the tongue  24  is raised, moving the tongue into the non-scraping towing position. When the piston rod is retracted by moving it in the direction opposite of the arrow  180 , the tongue is lowered, allowing the bottom edge  41  of the left-hand side frame rail  40  and the bottom edge  38  of the right-hand side frame rail  40  to contact the ground  44 , placing the ground scraper  10  into its scraping position, while the tongue can continue to move up and down in response to changes in the terrain, by due to the slot  172 , as discussed above. 
   Referring to  FIG. 8 , the scraper blade  118  is fastened to the scraper face  166  by the bolts and corresponding nuts  182 . The distal end  114  of the piston rod  115  is pivotally connected to a bracket  182 , which is in turned connected to an ear  184  that is connected to the left-hand scraper arm  98 . The distal end  110  of piston rod of the right side ram  18  is identically connected to the right-hand scraper arm  100 . 
   While the present invention has been described in accordance with the preferred embodiments thereof, the description is for illustration only and should not be construed as limiting the scope of the invention. Various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention as defined by the following claims.

Technology Classification (CPC): 4