Title:
EARTH MOVING PROCESS
United States Patent 3859741


Abstract:
In process of earth moving, severed earth is driven into transport means and transported, undesirable travel thereof is blocked, cross section of flow path of driven material is expanded as pressure of material so driven increases, and unloading the earth from the transport means at a substantially uniform bulk density is accomplished.



Inventors:
REINHARDT ROBERT L
Application Number:
05/447724
Publication Date:
01/14/1975
Filing Date:
03/04/1974
Assignee:
REINHARDT; ROBERT L.
Primary Class:
Other Classes:
37/195
International Classes:
E02F3/64; (IPC1-7): E02F1/00
Field of Search:
37/4,5,7,8,9,195 198
View Patent Images:
US Patent References:
3703776EARTH SCRAPER1972-11-28Feistel, Jr.
3637024TRACTOR MOUNTED, GROUND-RAKING AND ROCK-GATHERING APPARATUS1972-01-25Baskett
3533174EARTH-MOVING MACHINE WITH LOAD-DISTRIBUTING AUGER1970-10-13Carston
3533173EARTH MOVER WITH POWERED AUGER COMBINATION1970-10-13Fenske
3431659SELF-LOADING SCRAPER BOWL1969-03-11Eiger
3360824Rotating screw devices with draw-in pocket1968-01-02Schippers
3224119Earth moving scraper1965-12-21Wilmoth et al.
3210868Earthmoving scraper with auxiliary bowl mounted conveyor1965-10-12Liess
2602388Method of treating soil1952-07-08Elliott et al.
2464098Material loading and unloading apparatus1949-03-08Pittlick
2106759Wheeled scraper1938-02-01Paulsen
1505863Apparatus for removing snow or the like1924-08-19Chayer
1477212Apparatus for loading motor vehicles1923-12-11Eckertz



Primary Examiner:
Burr, Edgar S.
Assistant Examiner:
Eickholt E. H.
Attorney, Agent or Firm:
Silverman, Ely
Parent Case Data:


CROSS REFERENCE TO RELATED APPLICATIONS: The application is a continuation of patent application Ser. No. 345,225, filed Mar. 26, 1973, now abandoned, which in turn was a division of my co-pending patent application Ser. No. 257,638, entitled EARTH MOVING APPARATUSES AND PROCESS filed May 30, 1972 in the United States Patent Office, now U.S. Pat. No. 3,738,028 issued June 12, 1973.
Claims:
I claim

1. In the process of moving an earth severing means in a path across an earth surface, severing an upper layer of earth from earth below the surface of said layer, moving the severed earth particles into a transport means therefor and transporting the severed earth particles in a first forward direction, the improvement which comprises the steps of continuously containing and evenly driving the severed earth particles rearwardly to the rear of the transport means at one site while blocking movement of all particles thereof in an upward path transverse to the direction of said driving and out of said transport means and pulverizing particles of such severed mass and positively and evenly distributing such particles in said transport means and automatically expanding the transverse cross-section of the flow path of the driven material along the entire length of the driving thereof and automatically expandinng the top and bottom portions of the entrance orifice of the flow path of said driven material as the pressure of such particles so driven increases.

2. Process as in claim 1 including the step of raising the transport over said earth surface while so unloading the transport means.

3. Process as in claim 1 including the further step of compacting the unloaded earth wherein the earthy material driven to the front of the transport means and unloaded therefrom has a substantially uniform bulk density, and is spread and distributed during said unloading and thereafter compacted.

4. Process as in claim 3 including the step of raising the transport over said earth surface while so unloading the transport means.

5. Process as in claim 1 including the steps of transporting said severed earth particles and, at a second site distant from said first site, continuously and positively contacting and driving earth particles from the rear of the transport means to the front thereof and outward thereof and so unloading the transport means at a substantially uniform bulk density and even rate.

6. Process as in claim 5 including the step of mixing the severed earth with other substances, aerating and drying it and raising a discharge of the transport means over the earth surface while unloading said transport means.

7. Process as in claim 3 including the step of mixing the severed earth particles with other substances, aerating and drying them and raising a discharge of the transport means over the earth surface while unloading said transport means.

Description:
BACKGROUND OF THE INVENTION

1. THE FIELD OF THE INVENTION

This invention pertains to process of operation of wheeled self-loading excavating vehicles with a lifting conveyor.

2. DESCRIPTION OF THE PRIOR ART

Elevating scrapers with chains and paddles to pick up earth to carry the earth upwards and backwards into a bowl, in handling large earth aggregates, provide shocks to the chains that convey the paddles so that the forces on such machine elements are highly irregular loads, as irregular as the riprap and rocks that are encountered during the movement of such scrapers through the earth. Further, the operation of such apparatuses is noisy and ejects earth and dirt to such a degree that such machines may be heard and recognized a long distance away from their site of operation. Screw conveyors on earth excavators have not used shields thereover in a manner to provide accommodation for load surges or even loading and unloading prior to the invention herein disclosed.

SUMMARY OF THE INVENTION

For the process of moving earth severing means in a path across an earth surface, severing an upper layer of earth from the earth therebelow, loading the severed earth into a scoop transport apparatus and transporting and unloading the severed earth, the apparatuses of this invention use a pair of pivotally mounted hooded oppositely driven helical blades to continuously drive the severed earth rearwardly from the mouth of the bowl to the rear of the helical blades and, thereby, to the rear of the scoop apparatus. The hood resiliently held over the blades blocks any throwing of earth upward and outward of the scoop apparatus and also muffles the sound of the screw conveyor. The resilient connection between hood and conveyor provides for accommodation of surges of load by increasing the cross section of the screw conveyor and its carrying capacity for severed and ground earth particles and aggregates. The pivotal connection of the conveying assembly relative to the floor of the scoop apparatus provides that, during unloading of the scoop the conveying action of the screw assemblies evenly and smoothly removes the earth from the zone at the rear of that screw assembly, which zone is at the rear of the scoop apparatus, and provides for a uniform bulk density of the unloaded product even where it is lumpy, soggy or in aggegates and so improves the speed and efficiency of subsequent spreading and compacting operations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an earth moving assembly 19 including the scoop apparatus 20 according to this invention in its transport position with cutting blade 55 raised above the ground 27.

FIG. 2 is a top or plan view of the assembly of FIG. 1, partly broken away.

FIG. 3 is a sectional view along broken vertical section 3A--3A of FIG. 2 during severing stage of operation of scoop apparatus 20 when the bowl 24 is relatively empty. In FIGS. 1-3 the frame of scoop apparatus 20 is provided with four wheels and is drawn by the tractor to which attached.

FIG. 4 is a sectional view of apparatus 20 when such apparatus is in its severing operation and relatively full of earth: apparatus 20 is herein shown in sectional view along same position of a broken vertical section as 3A--3A of FIG. 2 but the scoop apparatus 20 herein is a part of an earth moving assembly including a tractor 25 and apparatus 20 is partially supported on as well as drawn by such tractor.

FIG. 5 is, in general, a sectional view of apparatus 20 as shown in FIG. 4 and viewed along the same broken plane as FIG. 4; conveyor assembly 23 is also broken away along vertical plane 5A--5A of FIG. 2 to show relations of left elevator screw blade 33 and left elevator shield 37 during handling of a load surge.

FIG. 6 is an end view of the conveyor assembly 23 along section 6A--6A of FIG. 5.

FIG. 7 is a diagrammatic piping diagram of the components or the hydraulic system 70 and their connections as used in embodiments 18 and 19.

FIG. 8 is a side view of the apparatus 20 during its unloading stage of operation.

FIG. 9 is a sectional view as in FIG. 4 of a modification of apparatus 20 during its unloading operation.

FIG. 10 is a diagrammatic view of a detail of conveyor motor support connection in region 10A of FIGS. 13 and 14.

FIG. 11 is a side view of a towed type or farm type scraper apparatus 318 with a farm type tractor 25; the scraper is shown in its earth engaging position and the conveyor assembly in its elevated position.

FIG. 12 is a top view of the apparatus 318 of FIG. 11.

FIG. 13 is a view of apparatus in zone 13A of FIG. 11 with the conveyor assembly thereof in its lowered position and the left side wall of the frame and bucket 232 removed to left of section 13B-13C of FIG. 12 while linkage from cylinder 211 to yoke bearing 239 is shown in side view in full.

FIG. 14 is a vertical sectional view of a motor scraper 319 in part supported by a tractor 25 as in FIGS. 4 and 5 with the elevator assembly in elevated position.

FIG. 15 is a side view of motor scraper 319 with elevator assembly lowered, as in FIG. 13, and bucket 232 raised as in FIG. 20.

FIG. 16 is a front view of the front end of conveyor assembly 228 as seen along direction of arrow 16A of FIG. 13.

FIG. 17 is a diagrammatic diagram for hydraulically powered connections to components of the apparatuses of FIGS. 11 and 14.

FIG. 18 is a diagrammatic side view of linkage between frame 262 and assembly 323 of apparatus of FIGS. 11 and 14 in the elevated position of conveyor assembly 323 as in FIG. 20.

FIG. 19 is a perspective diagrammatic view of the conveyor raising train assembly 133.

FIG. 20 is a side view of apparatus of FIG. 11 in raised position of conveyor assembly 323 and in dumping position of the bucket 232.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The scoop apparatus 20 serves to continuously sever each of several increments of earth to be moved from the site of their original location, to carry the sum of such increments of earth to the site or sites to which such earth is to be moved, and to discharge such increments of the thus severed and carried earth at the site to which such increments of earth are moved. The synergistic co-operation of the parts and operation of scoop apparatus 20 in the overall process of severing, loading, transporting and delivering earth is particularly demonstrated in its earth unloading or discharge operations.

In one embodiment 18 of earth moving assembly shown in FIGS. 4 and 5 the scoop apparatus 20 has two ground engaging wheels and is drawn by a tractor 25; the tractor 25 is then attached by a conventional hitch 26 to the apparatus 20; the tractor partially supports and draws the scoop apparatus 20 over the ground 27 and tractor 25, through a hydraulic liquid pump 72 driven by motor 71 of tractor 25, provides hydraulic power to the hydraulically powered components of apparatus 20.

Wheels 26C and 26D of the tractor 25 are shown in FIGS. 4 and 5. Another embodiment 19 of earth moving assembly shown in FIGS. 1-3 incorporates the same elements or apparatus 20 as in assembly 18; the scoop apparatus 20 is here provided with a separate motor unit 65 and is pivotally supported at its front end on a pair of permanently attached wheels 22C and 22D through a bolster or yoke 66.

The scoop apparatus 20 comprises a rigid frame 21 supported on a plurality of wheels, a conveyor assembly 23, a bowl assembly 24 and a hydraulic power system 70.

Frame 21 comprises a rigid sturdy left longitudinal arm 61, a rigid sturdy right longitudinal arm 62, a rigid sturdy rear transverse arm 63 and a rigid sturdy front transverse arm 64 firmly attached together, to form a rigid frame.

The rear transverse arm 63 supports heavy bowl adjustment screws as 83 (shown in FIGS. 3 and 5) to limit the rearward motion and location of the bowl 24 relative to the frame 21. In embodiment 19, the frame 21 is supported by four ground engaging wheels 22A, 22B, 22C and 22D permanently attached to the frame: in embodiment 18 the frame is supported at its rear by wheels 22A, and 22B permanently attached thereto; the front end of frame 21 is pivotally supported on the tractor 25.

In embodiment 19 of FIGS. 1-3 and 8 the front transverse frame arm 64 of scoop apparatus 20 is located pivotally on a bolster 66: in embodiment 18 of FIGS. 4 and 5 the front transverse arm 14 is firmly yet pivotally located and supported on a rear hitch 68 of tractor 25. The operation of scoop apparatus 20 is the same in the earth moving assembly 19 of FIGS. 1-3 as in the earth moving assembly 18 of FIGS. 4 and 5. The conveyor structure shown in FIG. 6 and hydraulic assembly of FIG. 7 is the same in the apparatus 20 in the assemblies of FIGS. 1-3 as in the assemblies of FIGS. 4 and 5. A modification of the conveyor structure of FIG. 4 is shown in FIG. 9: in the modification shown in FIG. 9 the process of operation is the same as the process of operation of apparatus of FIG. 4.

The bowl assembly 24 comprises a left side wall 51, a right side wall 52, a rear wall 53 and a bottom wall 54. These walls 51, 52, 53 and 54 frame reinforcement, are formed of rigid imperforate metal sheet and firmly joined together at their adjacent edges and surround a bowl cavity 50 which is open at its top and front: the front opening 56 is also referred to as the bowl mouth. A cutting blade 55 is firmly fixed to the front edge of the bottom wall 54 below mouth 56 and extends along the full width thereof.

The scoop apparatus also comprises a hydraulic system 70. This system includes a motor 65 in assembly 19 or 71 in assembly 18, which motor operatively connects to pump 72, a reservoir 74, and pressure relief valve 73. The pump and motor are located on platform 67 in embodiment of FIGS. 1, 2 and 3 and are located on tractor 25 in embodiment of FIGS. 4, 5, 11 and 20. Front left bowl elevator control piston assembly 77 and front right bowl elevator control piston assembly 78 are pivotally attached at their bottom to pins as 76 for piston 77 which is firmly fixed to frame arm 61 and a like pin on frame arm 62 respectively and to ears as left piston ear 81 on left and right bowl walls 51 and 52, respectively: the hydraulic lines 77L and 78L to such pistons respectively are controlled by a conventional three way valve 75 and provide for raising and lowering the front end of bowl 24 relative to the frame 21.

Support ears as 153 on left side wall 51 attached to outer sides of each side wall 51 and 52 support the bowl 24 in its forwardly tipped position as in FIG. 8.

Left and right rear bowl elevator control pistons 57 and 58 respectively pivotally attach at their bottom to lugs 117 and 118 respectively. These lugs are each firmly fixed to left and right frame arms 61 and 62 respectively. A rear upper stub shaft or lug 60 is attached to the outer side of left bowl side wall 51 near its top and the extensible piston arm 119 of left rear bowl piston assembly 57 is pivotally attached thereto: the extensible arm of right rear piston 58 is identical in size and shape to the arm 119 and its upper end is similarly attached to a lug similar to 60 on the outer surface of right bowl side wall 52. Arm 119 comprises a conventional piston rod for piston assembly 58. A sturdy transverse snubber rod 160 extends from top of wall 51 to top of wall 52 over mouth 56 and is firmly fixed at its ends to those walls. A pair of like resilient snubber blocks 161 and 162 are firmly attached to rod 160 and extend inwardly from the inner surfaces of walls 51 and 52 to contact the rear end of hood assembly 30 to prevent its turning further counterclockwise relative to bowl 24 shown in FIG. 4.

The rear end of hood 30 is provided at its center and bottom with a rigid snubbing foot 163 having a resilient tip to prevent contact of blades 33 and 34 with bowl floor 54 when the bowl 24 is empty of earth.

The hydraulic system 70 includes left hydraulic left screw motor 41 and right hydraulic screw motor 42 and hydraulic valve controls 42C and 41C therefor respectively, left and right shield control pistons 85 and 86 and left and right throttle controls thereof 87 and 88, and left and right front and rear conventional extensible elevator piston assemblies 77, 78, 57 and 58 and valve controls therefor as shown in FIGS. 2 and 7.

The conveyor assembly 23 comprises a left conveyor and shield assembly 31 and a right conveyor and shield assembly 32. Left conveyor and shield assembly 31 comprises a left shield 37 and a left helical blade 33 on a left screw shaft 35; right conveyor assembly 32 comprises a right shield 38 and right helical blade 34 on a right screw shaft 36. The shields 37 and 38 are firmly joined together at their central edges to form a hood 30. The conveyor assembly 23 is pivotally located within the bowl chamber 50 and pivotally supported at its front end by a transverse shield support shaft 49. Link assemblies 185 and 186 are each rigid and formed of a front rigid arm as 115 and 116 and a rigid rear arm as 85' and 86' respectively; which arms are adjustably yet firmly joined together by a plurality of bolts each located in one of several spaced apart holes therefor.

Shaft 49 is a rigid sturdy elongated bar that extends transversely of bowl mouth 56 and is firmly attached at its ends to arms 115 and 116 of link assemblies 185 and 186 and thereby is pivotally located at a fixed distance from the points of attachment (as 79) of the extensible link assemblies 185 and 186 to the frame 21.

The movement of the shaft 49 is thus limited, in operation by its pivotal connection to link assemblies having a fixed length to their pivotal connection to the frame at any fixed position of the bowl 24 on the frame 21. The hood of the conveyor assembly 23 extends transversely for at least 1/2 the width of the bowl assembly and the hood thereof is pivotally supported at its front end on the shaft 49. Shaft 49 provides a transversely extending movable axis; such shaft and axis are firmly connected to fixed points on the frame 21 and such fixed points determine a fixed axis for preventing longitudinal but permitting pivotal movement of the movable axis about those points on frame 21.

A transversely extending generally horizontal (in position of parts shown in FIGS. 1-6) rigid elevator ledge bar 59 is firmly fixed to one side (51) of the bowl 24, extends across the mouth 56 of a the bowl to the other side 52 thereof and is firmly fixed thereto.

A hood level limit arm 69 is firmly fixed to the shield support bar 49 and, in its lowermost position as in FIG. 3 rests on the ledge bar 59. This combination serves to prevent excessive lowering of the front end of conveyor asssembly 23 to such a degree that the edge of the screw blades 33 and 34 might contact and be damaged by the blade 55.

The hood assembly 28 comprises a rigid imperforate cover or hood 30, shaft support units 39 and 40, and forks 43 and 44: at the hood assembly 28 is generally, located over helical screws 33 and 34 and cooperates therewith and supports the screw shafts 35 and 36: the hood 30 comprises two like imperforate metal cylindrical sheets, left shield 37 and right shield 38. Each of shield 37 and 38 is of the same size and shape concave downward and the interior, lower, surface of each such shield is concentric with and slightly larger than yet substantially matches the outer edge of the helical screw therebelow as 33 and 34, respectively. The radius of curvature of the interior surface of each hood is slightly greater than the distance from the center of shaft to the radial edge of the helical screw.

The left screw blade 33 and the right screw blade 34 are mirror images of each other but are otherwise the same size shape and weight. The line 45 along which the shields 37; and 38 meet is hereafter referred to as the axis 45 of the hood 28. The central longitudinal axis of each of blades 33 and 34 and of shafts 35 and 36 are parallel to each other and to hood axis 45 when the conveyor assembly is empty or lightly loaded with earth as in FIG. 3. Left shield 37 has holes therethrough near its front end to slidably receive front rigid shaft support guide rods 93, 95 and 97 of the front left shaft support unit 39 and the left shield 37 has holes at its rear end to receive rigid rear shaft support guide rods 193, 195 and 197 of the rear left shaft support unit 139. The right shield 38 has holes at its front end to receive rigid front shaft support guides rods 94, 96 and 98 of the front left shaft support unit 40 and the left shield has holes at its rear end to receive rigid rear shaft support guide rods 194, 196 and 198 of the rear left shaft support unit 140. A chain 46 joins the output shafts of motors 41 and 42 to avoid one unloaded motor running free.

The left conveyor assembly 31 comprises a helical blade 33 firmly attached to and mounted on a rigid left elevator shaft 35. The front end 35' of the shaft 35 is rotatably yet firmly mounted in a resiliently movable front left shaft support unit 39; unit 39 comprises a rigid left metal support plate 91 generally flat and triangular in shape. Plate 91 has near its lower end a journal 99 for the shaft end 35' and at its upper end guide shafts 93 and 95 and a spring loaded bolt 97 firmly fixed to and projecting upward from the upper edge of the plate 91. A spring 101 is compressed between an adjustable nut on the head of the bolt 97 and a rigid rod guide 105 firmly fixed to the left shield 37 and resiliently urges the support plate 91 and shaft 35 toward the shield 37 to the limit permitted by the top edge of plate 91. The plate 91 has a convex curved upper edge 109 that matches the interior concave curvature of the left shield 37. The guide rods 95 and 93 are rigid stub shafts that project through and slidably fit in holes therefor in the shield 37 and help locate the shaft 35 and blade 33 relative to the length of the shield 37.

The rear end 135 of the shaft 35 is similarly rotatably yet firmly mounted in a resiliently movable rear left shaft support unit 139: rear left unit 139 is generally the same as unit 39 in structure: unit 139 comprises a rigid rear left metal support plate generally triangular in shape with near its lower end a jounal for the rear end of shaft 33 and guide rods 193 and 195 and a spring loaded bolt 197 firmly fixed to and projecting upward from the upper edge of the plate 191. A spring 301 compressed between an adjustable nut on the head of the bolt 197 and the rigid rod guide 305 (like 105) on the rear end of left shield 37 resilienlty urges the rear end of the shaft 33 toward the shield 37 to the limit permitted by the plate 191. The plate 191 has a convex upper edge that matches the interior concave curvature of the left shield 37. The guide shaft 193 and 195 are rigid stub shafts that project through holes therefor in the shield 137 near to the upper end thereof and also help locate shaft 35 relative to the length of the shield 37.

The shafts 35 and 36 are operatively connected to hydraulic drive standard hydraulic motors 41 and 42 respectively. The hydraulic motors 41 and 42 each comprise a movable rotor and a housing. Each rotor is firmly and fixedly attached to a shaft as 35 or 36 and each motor housing is provided with rigid brake arm as 47 or 48. Each such brake arm is slidably held in a fork therefor as 43 or 44, each of which forks is firmly attached to the hood 30 as to provide a base against which the torque of each motors 41 and 42 is applied relative to the screw shafts 35 and 36. The forks permit the brake arms to move upward and downward therein (up and down as in FIG. 3) relative to hood 30 and/or longitudinally of the length of hood 30. Such movement of the arms in the forks permits each motor as 41 and 42 which is firmly attached to a shaft as 35 or 36 to move upward and downward relative to the hood as the shaft attached thereto moves upward and downward relative thereto or as each shaft is skewed relative to the axis 45 of hood 30.

This structure permits that the shield portion 37 and 38 may resiliently move away from the shaft 35 and 36 respectively at the lower end of the shafts and pivot about the attachment of the guide rods as 193, 195, and 197 in the holes provided therefor in the shield 37 (and the like guide rods in shield 38).

The relations of the right shield 38 to the right shaft 36 and blade 34 are the same as described for the left shield and left screw shaft and blade; the left elevator assembly 32 comprises a helical blade 34 firmly attached to and mounted on a rigid right elevator shaft 36. The front end of the shaft 36 is rotatably yet firmly mounted in a resiliently movable front left shaft support unit 40; unit 40 comprises a rigid right metal support plate 92 generally flat and triangular in shape. Plate 92 has near its lower end a journal 100 for right shaft 36 and at its upper end guide shafts 94 and 96 and a spring loaded bolt 98 firmly fixed to and projecting upward from the upper edge of the plate 92. A spring 102 is compressed between an adjustable nut on the head of bolt 98 and a rigid rod guide 106 firmly fixed to the right shield 38 and resiliently urges the support plate 92 and shaft 36 toward the shield 38 to the limit permitted by the top edge of plate 92. The plate 92 has a convex curved upper edge like 109 that matches the interior concave curvature of the right shield 38. The guide rods 94 and 96 are rigid stub shafts that project through and slidably fit in holes therefor in the shield 38 and help locate the shaft 36 and blade 34 relative to the length of the shield 38.

The rear end of the shaft 36 is similarly rotatably yet firmly mounted in a resiliently movable rear right shaft support unit 140: rear right unit 140 is generally the same as units 40 and 139 in structure: unit 140 comprises a rigid right metal support plate generally triangular in shape with near its lower end a journal for the rear end of shaft 36 and guide rods 194 and 196 and a spring loaded rod 198 firmly to and projecting upward from the upper edge of the plate 192. A spring compressed between an adjustable nut on the head of the rod 198 and a rigid rod guide (such as 106) on the rear end of right shield 38 resiliently urges the rear end of shaft 36 toward the shield 38 to the limit permited by the plate 192. The plate 192 has a convex curved upper edge that matches the interior concave curvature of right shield 38. The guide shafts 194 and 196 are rigid stub shafts that project through hole therefor in the shield 38 near to the upper end thereof and also help locate shaft 36 relative to the length of right shield 38.

Thus, the lower end of the right shaft 36 may resiliently move to and from the shield 38, pivoting about the attachment to shield 38 of guide elements 194, 196 and 198 on the upper end of the support unit 140 supporting the rear end of shaft 36.

The shaft 49 is connected at its ends to the movable ends of the extensible ends 115 and 116 of the link assemblies 185 and 186 respectively. A clamp 145 with forwardly and rearwardly extending ears 146 and 147 is firmly fixed to the center of shaft 49. Outer sleeves 148 and 149 slidably embrace rod 49 and are firmly connected to a rigid transverse plate 150 therebelow. The plate 150 is firmly attached, as by welding, to the top of hood 30 and so provides a pivotal connection between the hood 30 and shaft 49. Snubber springs 151 and 152 are loosely wound around shaft 49 between sleeve 148 and clamp ear 146 and between sleeve 149 and clamp ear 147 respectively. A hood level limit arm 69 is a rigid arm that is firmly connected to hood 30 and plate 150: its tongue 69' usually overhangs shield support shaft and rests on shield support shaft 49 when the front of assembly 28 is in its lowermost position relative to the blade 55 as in FIGS. 1 and 3. Springs 151 and 152 provide a snubbing action on any sideways thrust occuring when one of the blades 33 or 34 meet a particularly tough obstruction.

The scoop apparatus of FIG. 9 is identical to apparatus 20 shown in FIGS. 4 and 5 and 8 and discussed hereinabove except that the apparatus of FIG. 9 has a pair, 156, of like link arms that connect the rear end of conveyor assembly 23 to the bowl 24. More particularly the right arm member 157 of set 156 comprises a set of serially connected rigid link bar elements 158 and 159: the right base link bar element 158 is pivotally connected at one, base, end to a sturdy pivot stud firmly fixed to the right side wall 52 of bowl 24 near to the top thereof and near to the rear wall 53, and at its opposite, free, end to the base end of the right distal link element 159. Right distal link bar element 159 is pivotally yet firmly connected at one, base, end to the free end of the right base link element 158 and at its other, distal, end is firmly yet pivotally connected to the right side of the rear end of hood 30. The link bar elements 158 and 159 are each rigid sturdy steel bars of substantially equal length and size and the pivotal attachments thereof are at journals at the ends of each such bar: the pivotal attachment therebetween and the pivotal attachments between such elements and bowl 24 and hood 30 are strong and permanent. A similar set of serially connected rigid link bar elements (not shown) of set 156 similarly connects the left rear end of the hood 30 to the left wall 51 of bowl 24. The pair of link arms limits the forward travel of the top of hood 30 to prevent it from turning counterclockwise (as shown in FIGS. 3, 4 and 5) farther than 90° from the vertical and supports the rear end of the hood to prevent contact of the blades 33 and 34 with the floor 54 of the bowl when the bowl is empty of earth, but does not otherwise limit the above described movement of conveyor assembly 23 to maintain contact continuously with the mass of earth in the bowl 24. When the link arms of pair 156 are used the snubber rod 160 and snubber block 163 may be removed.

In the normal loading operation of the earth moving assemblies as 18 and 19 incorporating the apparatus 20, the shafts of front piston assemblies 77 and 78 are retracted and the scraper blade 55 lowered to engage the ground and then extend below the surface thereof to a desired depth of cutting. The running frame 21 is then drawn, as by a tractor 25, over the ground 27 in direction 29 of FIG. 3: thereby the upper layer of earth 121 above the level 122 of the cutting blade forward edge is severed from the earth 123 therebelow and thereafter passes over the blade 55 on continuance of the forward movement (or "crowding" action) of the moving bowl and cutting blade due to the resistance to compression of the severed earth. Thereupon, the thus severed and dislodged earth, accumulates at the mouth of the bowl 24 above and to the rear (right in FIGS. 1-5) of the blade 55. During such steps of the operation of loading earth into the bowl 24 the helical blades 33 and 34 are driven by the motors 41 and 42.

As the conveyor assembly 23 pivots about its front end and extends the full length of the bowl floor each of the helical blades 33 and 34 of the screw assembly 23 maintains driving contact with the top layer of earth 90 in the bowl along the full length of the hood unit 30 and moves it backward, as shown in FIG. 3, from its mouth to its rear wall 53.

The longitudinal extent of contact of the helical blades of the conveyor with the earth in the bowl, by driving such earth 90 to the rear of the bowl, minimizes or eliminates development of points of high level of earth in the forward portion of bowl 24. The hood 30 extends vertically from the tops of blades 33 and 34 down to the axis of the shafts 35 and 36 and laterally more than 1/2 of the width of the bowl, i.e., about four-fifths of the distance between walls 51 and 52 in the preferred embodiment.

The hood 30 and the left and right skirts 110 and 111 dependent therefrom extend downwards to upper surface of ground 27 as shown in FIG. 14 and prevent the rotatory action of the blades 33 and 34 from throwing rocks and earth outward of the bowl 24; the blades work with a minimum of clanging noise, although there is a "swish" and low infrequent "clunking" sound.

Where a slug or temporary larger amount of earth than usual is forced into the mouth of the bowl, as when a hillock, as 124, over the usual level of surface of ground 27 is met, or when a particularly large amount of tough earth aggregate is forced into the mouth of bowl 24, while the conveyor assembly is in one given sloped position, as in FIG. 4, the conveyor assembly pivots to a more horizontal position position as in FIG. 5 but, because of the previous movement to the rear of the earth moved into the bowl there is no, or a minimum of, flow or loss of earth from the bowl out of its mouth notwithstanding the movement of the lower portion of the elevator assembly away from the surface of the mass of earth in the bowl which surface was theretofore in contact with the helical screws 33 or 34. Further still, because of the resilient and yieldable connection of the lower ends of the shafts 35 and 36 from the hood 30, when such surges of increased rate of feed of earth 90 to the screws 33 and 34 occur, the space or volume between shafts 35 and 36 and hood 30 resiliently increase automatically expanding the transverse cross section of the flow path of the driven material along the entire length of the driving thereof and automatically expanding the top and bottom portions of the entrance orifice of the flow path of the driven material as the pressure of such particles increases by compression of springs as 101 and 102, as shown in FIG. 5 and illustrated in FIG. 6 for left support unit 39 and left shield 37, and thus promotes the volume capacity for forced flow by the helical blades 33 and 34 along the shaft 35 and 36 of each such screw conveyor. The fact that there is a space between the edge of helical blade as 33 and the interior of its shield as 37 does not permit earth leakage downwardly therepast durng turning action of the blades 33 and 34 because the flow of particulate solids such as loosely flowing earth is not, especially in this circumstance, controlled to the same quantitive degree by the same factors as the flow of a liquid fluid under such a mechanical situation although there are some fluid characteristics to this loaded earthy material. Accordingly, notwithstanding the yielding and accommodation of the assembly 23 to such surges, the flow of earth along assembly 23 continues with a mass flow rate corresponding to a somewhat larger volume screw rather than by jamming as occurs where there is fixed relationship of such a shield or hood structure or wall to the screw. After the action of severing the earth and distributing it in the bowl 24 as above described the piston assemblies 77 and 78 are extended and raise the blade 55 above the level of the ground 27, as in FIG. 1, from the lowered position of that blade as shown in FIGS. 3, 4, and 5; the rear pistons do not then have to extend. The apparatus 20 is then drawn behind a vehicle as in assembly 18 or assembly 19 and then carries or conveys or transports a load of earth or the like particulate material that has a stable angle of repose, although it can be caused to flow by tilting the floor 54 as shown in FIG. 8.

In unloading earth from the bowl 24, with the orientation of earth 90 and conveyor assembly 23 in the bowl 24 as in FIG. 4 and the elevation and orientation of the bowl 24 relative to the ground 27 the same as shown in FIGS. 1 or 9 the motors 41 and 42 and shafts 35 and 36 are turned in the direction opposite to the direction in which each was driven to load the bowl 24. This causes a controlled discharge of the earth from the bowl 24. On so unloading such earth from the bowl 24, because of the location of the pivotal connection by assemblies 185 and 186 between assembly 23 and frame 21 and because of the pivotally movable support and relation of the screw conveyor assembly 23 on the mass of earth in the bowl 24, during the operation of unloading earth from bowl 24, blades 33 and 34 of conveyor assembly 23 continuously maintain driving contact with upper lower layer of the mass of the earth to be moved out of the bowl 24. The blades 33 and 34 are driven by motors 41 and 42 to rotate at uniform speed via pump 72 during such unloading operation and have continuous contact with the earth in the bowl over the entire length of the blades 33 and 34: the blades extend over the major portion of the length and width of the bowl; there is accordingly a subtantially even and controlled rate of discharge of earth in the bowl 24 from the bowl during discharge thereof as the apparatus 20 is drawn over ground as 27. The even rate of flow and deposit from the scoop apparatus of the earth transport device 18 or 19 facilitates the following smoothing operation by scrapers and rollers and accordingly significantly improves the overall speed and economy of cutting, moving, unloading and smoothing earth.

The bowl support pistons 77, 78 and 57 and 58 and the conveyor assembly 23 thus provide for three different types of emptying action: firstly, a smooth even controlled emptying of earth, to level of bottom of its wheels, i.e., on to ground level, to a depth of a few inches for subsequent more efficient and rapid compaction: secondly, a rapid dumping action by tilting as shown in FIG. 8: and thirdly, an even deposit of the earth carried by bowl 24 into a mass of substantially greater height than in the first operation, by use of conveyor assembly 23 to empty the bowl while the mouth of the bowl 24 is supported, as in FIG. 9, at a greater elevation as 127 than that from which it severed the earth as in FIGS. 3 and 4.

Extension of the arms 115 and 116 of assemblies 185 and 186 to move the shaft or bar 49 further away from their pivot supports as 79 and in line with ledge bar 59 provides that the screw 35 and 36 may be moved away from the bowl floor 54 to minimize interfering or controlling contact by the blades of the screw assembly with the flow of earth from interior of the bowl past the blade 55 when the bowl floor is tilted for rapid dumping as in FIG. 8.

Also the bowl floor 54 may be raised from position shown in FIG. 1 while strongly tilted as in FIG. 8 or slightly as shown in FIG. 9 while the flow from the bowl 24 is controlled by conveyor assembly 23; this provides for an increase in height of material expelled from the bowl 24, such expelling being accomplished at even and controlled rate of flow as well as up to any desired height to the limit of extension of piston assemblies 57 and 58 and 77 and 78.

The first unloading operation is thus accomplished by principal dependence on the assembly 23 to remove the earth from the bowl 24 while the rear of the bowl floor is subtantially at the same height as the height at which the assembly 20 is operated to sever and transport earth, as shown in FIG. 1: and piston 57 and 58 need not be extensible for this purpose.

The second operation is accomplished by use of the piston assemblies 57 and 58 to raise the lower rear edge of the bowl floor as shown in FIG. 8 and increase the angle of the floor 54 to dump the earth, while using conveyor assembly 23 only to avoid "hang-up" or moving the screw assembly by pistons 85 and 86 out of contact with the flow of earth. The third type of unloading operation utilizes the action of the pistons 77 and 78 as well as 57 and 58 to raise the floor 54 of the bowl 24 so that conveyor assembly 23 will expel the earth from the bowl 24 at a height determined by the pistons assemblies 77 and 78 in excess of the usual height of operation of the bowl floor during severing and transport action as well as at a substantially uniform rate of flow and, consequently, at a substantially uniform bulk density; such condition of the discharged material greatly facilitates the subsequent compaction and smoothing of such deposited mass. This third operation is of particular value where the bulk density is desired to promote aeration of the deposited material and, for reasons of either limited dumping area or desired increase in mass temperature with increased depth of deposit due to biochemical action in the mass, and increased height of such mass or deposit is desired.

The first and third operations are of particular value where the material emptied does not flow readily, as with manure.

In a particular embodiment of apparatus 20 the helical blades are 18 inches in diameter and are driven at about 400 r.p.m. The assembly 23 is substantially lighter than conveyor assemblies using paddle blades as drags usually used with chain conveyors for earth movers and, because of such light weight, increases the efficiency of severing, loading, transport and unloading above described.

Hydraulic pistons 85 and 86 may be provided as power adjustment assists operatively attached to the same pins, as 79 and ends of arm 49 to which the link assemblies 185 and 186 respectively are connected in order to move such connections to effect length adjustment of the adjustable links as 185 prior to fixing such links at such length as are desired therefor as above described.

As shown in FIGS. 2 and 7 controls for the hydraulic assembly 70 may be located in a console 112 located on tractor 25 and operatively connected to the components of the hydraulic system 70 in conventional manner.

Structures indicated by referent numerals as 25, 33, 34, 73, and 74 shown in the drawings for embodiments 18 and 19 are the same structures respectively referred to by those referent numerals discussed for embodiments 318 and 319 herebelow discussed and illustrated.

In yet another embodiment 319 of earth moving assembly shown in FIGS. 14 and 15 the scoop apparatus 320 like 20 has two ground engaging wheels and is drawn by a tractor 325; the tractor 325 is then attached by hitch as 326 to the scoop apparatus 320; the tractor 325 partially supports and draws the scoop apparatus 320 over the ground 27. Tractor 325, through a hydraulic liquid pump driven by motor 71 of tractor 325 and through its power take off 201 provides hydraulic power to other hydraulically powered components of scoop apparatus 320 as also shown in FIG. 17 for tractor 25. The scoop apparatus 320 comprises a rigid frame 321 like 21 supported on a plurality of wheels, a conveyor assembly 323, a bowl assembly 324 and a hydraulic power system 270.

Another embodiment 318 of earth moving assembly according to this invention is shown in FIGS. 11, 12, and 20: it incorporates substantially the same elements of apparatus 320 as in assembly 319; the frame for the scoop apparatus 320 is here pivotally supported at its front end on a pair of permanently attached wheels 22C and 22D through a bolster or yoke as 66 and the height of its front end is adjusted by hydraulic pistons 218 and 218'. Embodiment 318 has a tractor 25 with a motor 71.

In embodiment 319, the frame 321 is supported by four ground engaging wheels as 22A, 22B, 22C, and 22D permanently attached to the frame: in embodiment 318 the frame 321 is supported at its rear by wheels 22A and 22B permanently attached thereto; and the front end of frame 321 is pivotally supported on the tractor 325 and adjusted as to height by an adjustable hydraulic piston 218.

In embodiment 318 of FIGS. 11, 12, and 20 the front transverse frame arm 264 of scoop apparatus 320 is located pivotally on a bolster 266: in embodiment 319 of FIGS. 14 and 15 the front transverse arm 264 is firmly yet pivotally located and supported on a rear hitch of tractor 325. The operation of scoop apparatus 320 is the same in the earth moving assembly 318 of FIGS. 11, 12, and 20 as in the earth moving assembly 319 of FIGS. 14 and 15. The conveyor structure shown in FIGS. 16, 18, 19, and 20 and hydraulic assembly of FIG. 17 is the same in the scoop apparatus 320 in assembly 318 of FIGS. 11, 13, and 20 as in assembly 319 of FIGS. 14 and 15.

The conveyor assembly 323 of apparatus 318 and 319 of FIGS. 10-20 is the same as assembly 23 of FIGS. 1-9.

FIG. 11 shows the farm type scraper 318 loaded, with the cutting blade 216 still in the ground 27 while that assembly 323 (like 23 above described) is in the full up position, which is at an angle which approximates the repose angle of the dirt 90 or other material loaded. In this case, the scraper is towed by hitch 26 with a four wheel type tractor 25 having a power take off shaft 201 and can make cuts from 1 to 8 inches deep in a single pass.

The power take off shaft 201 is plugged into and turns the hydraulic pump 272 (like 72 above described). The power take off shaft 201 is turned on and off by means of a suitable operating lever 221 on the tractor platform connected to motor 71 and shaft 201. When the operator wants the assembly 323 to be powered, he puts that lever 221 in its "on" position. Hydraulic pressure is transmitted through hose 206 to the hydraulic motors 41 and 42 which operate the screws as 33 and 34 through a reduction gear box 235. Control of motor action is supplemented by a control valve 214 in embodiment 319.

A hydraulic relief valve, FIG. 17 (209), is incorporated into the hydraulic system 270 between the up and/or high pressure line 206, and the down or return line 205. The hydraulic liquid or oil in normal operation, or relief, will return back to the filter 204 before going into the reservoir. The reservoir 207 is fitted with a filler cap and vent 203, and a set of torque bars, 202, to prevent the hydraulic reservoir 207 from turning, but still faciliate ease of scraper connection or hook up to the tractor, as 25 or 325.

The assembly 323 has a hydraulic system 270 which is a closed loop system. Thus hydraulic lines of system 270 to motors do not have to be removed when disconnecting the scraper from the tractor: rather, the reservoir 207 and pump 272 are disconnected from the power take off shaft 201. It it is advantageous to leave the assembly 328 in the full up position (about 45°), the small valve 219 (shown in FIG. 7) includes a one way check valve 219C and a restrictive orifice 219R which is normally restricted or passage through valve 219R can be completely blocked as desired: if blocked or turned off when the assembly 323 is fully in the up position, it will stay at 45°, or otherwise at whatever angle is desired by completely blocking the restriction bleed back 219R. The vent or restriction is normally used to keep the assembly 323 from falling back into the fully reclined position to quickly.

Two of the four control hoses, 210 and 210' (in FIGS. 11 and 17) are used to actuate the scraper dumping cylinders 212 and 212'. Two of the hoses (shown in FIG. 17) as 210" and 210'" are used to raise and lower the cutting edge 216 by means of a single cylinder 218 (as shown in FIG. 11) on a scraper pulled by a four wheeled farm type tractor or, by double cylinders 218' and 218" where such are used on industrial motor scrapers as shown in FIGS. 4 and 14 and controlled by a valve 258.

A sectional cutting blade assembly 216 is held in place on cutting hanger 226 by bolts and can be changed or reversed by means of such bolts. Suitable side cutting blades 215 (shown in FIG. 11) are also provided to trim the vertical side of the cut, so the rear wheels of the scraper are always inside the cut.

A scraper bucket stop 244 is firmly attached to the rotating bucket 232 (FIG. 11). In the lowered position of the bucket that stop rests against the scraper side frame top plate as shown in FIG. 11. The bottom of the assembly 323 is held in place by a rigid U-shaped yoke 217 with arms adjacent to and supported on the scraper frame side wall, by means of pins 220 and 220° which can be adjusted forward and aft in several positions. Suitable front and rear bearing caps 229 and 230 are firmly attached to and provide hinge points on top of the conveyor assembly frame 228. Rear yoke 237 and front yoke 217 are both rigid and U-shaped and pivotally held in rear bearing cap 230 and front bearing cap 229 respectively on rear and front of top side of assembly 228. Each of the rear or bottom ends of arms of yoke 237 (as 237') is pivotally connected to an arm of a crank 213. Each crank as 213 is formed of a lateral rigid short vertically and longitudinally extending crank arm portion 130, a rigid transverse center portion 131 and an interior vertically and longitudinally extending rigid arm portion 132. Portions 130, 131, and 132 are firmly joined together as shown in FIG. 19. The center crank arm portion 131 is cylindrical and pivotally supported in a journal 233 in the frame 321 of the scraper assembly. The central crank arm portion 131 passes from inside of frame 321 through scraper bucket trunion hangers or journals 233 to the outside of the scraper frame of assemblies 318 and 319. A pair of extensible conveyor cylinders 211 and 211', one on either side of the scraper frame attach to the outside trunion crank arms as 130 and provide assistance in raising the assembly 323 from a near fully reclined position as at the start of the loading cycle as in FIGS. 3 and 13 to the full, or approximately 45°, position when the bowl is filled or at the end of the loading cycle as in FIGS. 4 and 14. By the connection as shown in FIG. 17 as difficulty or mechanical resistance is encountered by the assembly 323 (or other elevating means of loading the scrapers) hydraulic pressure in line 206 is raised which pressure is transmitted to the two conveyor cylinders 211 and 211', which slowly raises the assembly elevator 323 by means of crank arms as 213 and yoke 237. As the torque builds up in the gear box 235 and hydraulic motors 41 and 42 the hydraulic pressure raises to a point where it approximates the loading weight of the assembly elevator mechanism. As a result cylinders 211 and 211' start to work by extending the pistons therein, as 211P, raising the conveyor assembly 323 or other conveyor means. On continued loading, a "balancing act" or interaction of these resistances takes place until the conveyor assembly 323 (or other loading means) reaches its uppermost position. In embodiments 318 and 319 motors 41 and 42 are each operatively connected to a gear box as 235 and, respectively, drive screws 33 and 34 of assembly 323.

The assembly 323, like 23, is provided with the means by which it can be very flexible in operation. In other words the shield, frame, or cover shown as 228 in FIG. 16, like hood assembly 28 in FIG. 5, can raise away from the helical screws and their attaching bearings, as 99' and 100' (like 99 and 100) and bracket 227 (like 39) and compress the coil springs and adjustment assembly (such as 39 and 40) and shown as 224 and 224' in FIG. 16. Alignment pins 223 (like rods 93, 94, 95 and 96 of FIG. 6) are used to keep bearings as 99' and 99 and 100 and bearing support plates as 227 in correct alignment: the pins 223 being attached firmly to bearing support plates as 27 and loosely fited into suitable holes in the cover and frame formed by hood or shield assembly 28. Each side of the rear end of the conveyor assembly 323 comprising shield and frame assembly 228 and helical screws as 33 and 34 comprises (as shown in FIG. 10) a diagonally welded member 236 firmly attached to the gear box 235, and a means of spring compression shown as a nut, bolt and spring 233.

The screws as 33 and 34 of assembly 323 while loading provide a small chopping motion on the dirt which they urge upward from the cutting edge 216. If a stone, tree root, or other sizeable obstacle or object is encountered while loading, the foremost, or front end of the conveyor assembly 323 will raise up and over such an obstacle. If this object, root, rock, or the like becomes wedged in between the helical screw as 33 and its hood, the shield and screw working together will compress the coil spring, as adjustment 224 in FIG. 6 (as for springs 101 and 102 in FIG. 6) and relieve the condition, permitting the object to dislodge.

A means of adjusting the distance between the helical screw blades as 33 and 34 of assembly 323 and the cutting edge 216 is accomplished by means of rigid adjustable side brackets 225 and 225' (FIG. 6) each of which is pivotally supported by a pin 245 at its rear end (FIG. 11) to a portion as 226 of frame 321, but adjustable in height with a front pin as 240 and a plurality of suitable holes as 241 and 242 spaced at regular vertical intervals for one of several relatively upward or downward positions of the pin as 240 and bracket 225 (and likewise for 225').

The front end of conveyor assembly 323 is urged to stay down; the center of yoke 217 is urged resiliently downward and thereby its ears 217C and 217D are urged into contact with the adjustment brackets 225 and 225', as shown in FIG. 6, by coil springs 222 and 222' which springs are held resiliently yet firmly at their centers 242 and 243 to a collar 247: collar 247 is firmly held to shaft 217. Springs 222 and 222' are under tension and wound around central, transverse portion 249 of yoke 217 and urge the rear end of arms 217A and 217B of yoke 217 upward and are thus wound in such a manner that they continually force the lower front end of the conveyor assembly 323 downwards into the dirt 290 being urged upwards by the cutting edge 216.

In dumping the scraper while supported in the blade up, or transport, position by cylinder 218 in FIG. 11 (or by a pair of cylinders 218' and 218" in FIG. 14), the blade 216 is approximately 8 inches above the ground; a suitable control valve 248 on the tractor as 325 or 25 is actuated, and the high hydraulic pressure is routed through hoses as 210 and 210' to the dumping cylinders 212 and 212' which rotate the scraper bowl 232 around suitable trunion bearings as 233 (concentric with arm 131) on the scraper frame. The bowl 232 then tips up and strike-off blade 238 at front end of bucket 232 smoothly levels out or "strikes off" dirt 291 to the desired lift or thickness as shown in FIG. 20. By raising or lowering the entire scraper by means of cylinder 218 (or 218' and 218") in conjunction with the desired strike-off position of the bowl 232 through hydraulic cylinders 212 and 212' a smooth controlled dump can be achieved.

The conveyor assembly 323 can slowly retract into its lower position as shown in FIGS. 3 and 13 (as the dirt 90 falls out of the bucket 232) without touching the rear wall of the bucket 232 if the bucket remains open. This is an advantage while repairing haul roads, and the like, where the scraper blade 216 is used to drag the haul road with the strike-off blade 238 also adjusted to drag the ground. The conveyor assembly 323 is sometimes oprated in the down position to remove the dirt urged upward by the front cutting blade 216 and passed over the blade base as at 292 (FIG. 15): the screws 33 and 34 are operated to pulverize and break up such earth. The thus treated earth is then smoothed out by the rolling bucket strike-off blade 238 as shown in FIG. 15 at 293.

Some advantages of the screw assembly type elevator 323 shown over conventional chain and drag types are that it is:

1. Faster and smoother loading;

2. Impacts are avoided due to continuous helicoidal blade action; 3. The screw conveyor 33 cuts and pulverizes the soil into small pieces, thus making final compaction easier;

4. Dust, due to the cover or shield 30 or 228 is reduced. Such cover may also be used as a flexible or fixed unit on the chain-drag units;

5. Less noise because there is no impact noise. On chain and drag type scrapers the drags touch the soil and/or rocks, etc., two times per second. At the point of loading they are very noisy;

6. Cost to build; the screw assembly 23 (and 323) is considerably less in cost than chain and drag units and repair parts cost less;

7. Safety is assured because the screws are covered, which keeps rocks and like objects from flying forward and hitting the operator in the tractor as well as elsewhere in the vicinity of operation of the apparatus 18, 19, 318, or 319;

8. With the bucket open and the screw assembly as 323 in its down position as in FIG. 15 the unit does an excellent job of mixing and drying soil with the cutting edge 216 in the soil to be mixed, blade 238 contacting the ground, and bucket 232 open, soil to be mixed with cement or soil stabilizing chemicals, etc. is moved over the cutting edge 216 and pulverized by the screw blades, and spread by the strike-off blade: the same operation is performed to dry the soil to specifications prior to compacting. This enables the contractor to get back to work earlier after rains;

9. The units 318, 319, 18 and 19 will load snow, ashes, manure, chemicals, processed or selected materials for transport and/or mixing. This is especialy useful where several types of clay and/or aggregates and soil are layered in different lifts or stratas and then a cut made through the layers at a 90°, or right angle to the direction of lay down. A composite and easily controlled percentage of the whole mass will result;

10. The rolling buket 232 permits not only fine spreading but fast dump over a "grizzly" or opening to a mill or the like. The extreme tilt of the bucket permits rapid and complete ejection of the load at any time, while the scoop apparatus 20 or 220 is moving or still.

The valves 248 and 258 in system 270 are preferably part of a single valve with two spools of three different positions for three different combinations of directions of flow through each of such spools as shown in FIG. 17 with those two spools physically held or tied together to provide only one common open center position.

Each of link assemblies 185 and 186 is preferably located immediately adjacent to and in loose sliding contact with the outer surface of bucket 24 by location of its pins as 79 (and 79' on the inside of the rigid frame members as 61 (and 62) as in FIGS. 1 and 6 and 8 or on the bottom thereof, although, for purpose of illustration, shown on outside of such frame members in FIG. 2.

On the farm type scraper assembly 318 as shown in FIG. 11, the three position valve 214 shown in FIG. 17 may be removed --because usually not there economically feasible--and high pressure line 206 and return line 205 connect the hydraulic pump 272 to motors 41 and 42 in the manner indicated by the uppermost diagrammatic array of channels in valve 214. The hydraulic fluid under pressure then passes direct to motors 41 and 42 from the pump 272, which pump is controlled by the power take-off clutch 221, which clutch is controlled by the power take-off control lever 221' shown on tractor 25 in FIG. 17. On motor scrapers such as shown as 325 in FIG. 14 (and in FIG. 4) the three way valve 214 as shown in FIG. 17 is usual.

The entire hydraulic assembly as shown in FIG. 17 can be used on a tractor as 325 in an assembly as 319 (FIG. 14); then the three way valve 24 is primarily used for control of he motors 41 and 42 instead of the power take-off clutch 221' and its control lever 221 as is used on farm type scrapers as 318 in FIG. 11. The value 214 is used for an assembly as 319 in the assembly shown in FIG. 17 with the quickly attached and/or disconnected reservoir 207 and hydraulic conduit lines 307 and 308 (corresponding to hydraulic conduit lins 107 and 108 in FIG. 7): such hydraulic lines 307 and 308 are easily, rapidly and reliably connected to the tractor 25 or disconnected therefrom as at couplings 307A, 307B, 308A, and 308B so that the tractor 25 may be removed from the scraper apparatus and be used for other purposes.

The closed loop system 270 of FIG. 17 comprising pump 272, motors 41 and 42 of assembly 323, relief valve, filter and reservoir 207 can be readily detached from the power take-off shaft 201 as shown in FIGS. 11 and 17 because the reservoir 207 and parts cooperating therewith as filter 204, valve 209, lines 205 and 206 are separate from the other portion, 271, of the system shown in FIG. 17, which other portion 271 operates (a) the cylinders 212 and 212' that elevate and dump the bowl or bucket 232 and (b) the cylinders as 218 and 218' that raise the scraper frame and cutter blade; such portion 271 uses the tractor hydraulic system, which has a two-spool three-position open center valve 348, including as components three-position spools as 248 and 258, on the tractor frame or on a separate pedestal. The hydraulic lines 312 and 312' quickly and reliably attach to and detach from the hydraulic pressure lines outlets of the farm tractor 25 at conventional quick connect connectors as 307A, 308a, 307B, and 308B respectively in the vicinity of the hitch for the tow bar 208 (or pull yoke) as shown in FIG. 11.

This two-pump system of FIG. 17 is distinct in structure from the system shown in FIG. 7 where the hydraulic power to and control of the bucket and the elevator assembly can be powered by one pump and reservoir and stack valves built into the motor scraper as a part of that assembly and/or the motor scraper, as 319 or 18, is a permanently attached combination of a complete two wheeled tractor and a two wheel scraper and there is no need for a detachable hydraulic reservoir and closed loop system as in FIG. 17. The farm tractor and scraper combination 318 as in FIGS. 11, 12, and 20 is arranged so that the scraper unit 320, which may be quickly attached to tractor 25, may be quickly detached from the tractor unit as 25 and the tractor unit can then be used for other purposes.