US2243831A

US2243831A - Scraper

Info

Publication number: US2243831A
Application number: US275173A
Authority: US
Inventors: Berner Leo
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-05-23
Filing date: 1939-05-23
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

1June 3,1941.

L. BERNER scRAPER Filed may 23. 1939 2 Sheets-Shea?l 1 L. BERNER- June 3, 1941*.

SCRA'PER Filed May 23, 1939 2` Sheets--Sheml 2 @Y HAR A5 K/ECH FO aff Patented June `3, 1941 UNITED STATES PATENT OFFICE Leo Berner, Huntington Park, Calif. Application May 23, 1939, sex-iai No. 275,173

17 Claims.

Myinvention relates to earth-moving apparatus with special reference to scrapers and is directed speciically to an improved vconstruction for a heavy duty scraper of large capacity; f

The earth-moving cycle of ascraper lcomprises the following operations: digging or the scraping operation proper; the loading of the excavated earth into the bowl of the scraper; the transportation of the loaded earth in the scraper to the dumping area; and unloading the earth at thev dumping area, usually the earth being spread to a desirable thickness as it is deposited. The amount of earth that will be moved in a given lperiod of time by a given amount of available power will vary with the effectiveness with which that power is utilized in the digging operation and with Athe time ratio of the digging operation to the whole earth-moving cycle. The

most economical scraper, then, would be one with a highly effective digging means and a relatively large storage capacity to reduce the number of trips necessary for moving a given yardage of earth.

In practice, certain diiculties have defeated attempts to attain large capacity in Scrapers, increasedcapacity along conventional lines uny operation, per se.

avoidably involving prohibitive penalties in reduced eiciency and increased cost.`

One of the most serious problems is the fact that increasing the storage capacity of a conventional scraper results in an inordinate consump tion of power for loading theearth into the scraper bowl, the power so consumed being a direct deduction from the power available for the digging operation proper. This problem arises from the fact that, in the usual scraper construction, the earth is shifted from the scraper blade to storage in an ineiiicient manner, the earth movement into the bowl being accomplished solely by `displacement resulting from earth crowding into the scraper upward from the scraper blade. All

of the loading force is applied at the scraper blade and is rapidly dissipated. Internal friction of the loaded earth in the crowding action consumes energy, and packing of the earth against the side walls of the scraper with considerable pressure causes excessive resistance to the loading flow of the earth. This dissipation of power is unavoidable if mere crowding ,of the earth is relied upon for loading the conveyor and increases at an accelerated rate with increase of bowl capacity. In only a moderate sized scraper, the power consumed in forcing the earth into the scraper bowl for transportation may exceed by aV large margin the power consumed in the digging Since the loading operation .proceeds simultaneously with the digging operation, a conventional scraper of exceptionally large capacity will often require a pusher tractor in addition to the usual pulling tractor. The employment of two tractors in such manner is not only expensive but also involves excessive stresses on the scraper that can be met only by a heav and cumbersome scraper construction.

It may be further pointed out that relying on the sheer crowding of the earth at the blade for conveying the earth into the tractor bowl is not conducive to ecient distributionof the load nor to proper utilization of the available storage volume. Where crowding is depended upon to load the tractor, the earth must be considered as, in effect, a stream flowing from the cutting edge of the scraper blade into the bowl and no design based on the sole consideration of facilitating ,such flow will result in proper loading .of the bowl.

The general object of my invention is to provide various improvements in a scraper construction to obvlate the abovedidiculties and to solve the above problems in the design of a large capacity scraper. Broadly, it is my purpose to provide a large capacity scraper that may be operated effectivelywithout excessive power requirements. I propose to provide alarge capacity scraper in which the power requirements for excavation compare with the power requirements of conventional Scrapers .of relatively small capacity. Conversely stated, my broad Objectis to excavate with maximum utilization of a given available power and at the same time to provide such carrying capacity on the part of the` scraper that the ratio of the digging operation to the earthmoving cycle as a whole will be relatively high.

My invention is characterized by the conception that these broad objects may be attained by concentrating lsubstantially all of the available power on each operation of the earth-moving cycle in turn. By concentrating the available power alternately on digging and loading, I avoid the peak power loads that are inevitable when digging and loading are performed simultaneously. My invention is further characterized by the unique conception of, in effect, dividing the bowl intoa receiving compartment and a storage compartment, my thought being that the earth may be conveyed into the receiving compartment by the usual crowding action with relatively little consumption of the available power if the receiving compartment is relatively small and is designed to favorlowing movement blade, per se.

of the earth. A new earth-moving cycle is con` tem-plated in which the early part of the cycle consists of :alternately digging with forward movement of the scraper and, with the scraper stationary, loading or transferring earth from the receiving compartment to the storage comthe construction o-f the contemplated receiving compartment of the scraper bowl. I propose to provide for transferring earth from the receiving compartment to the storage -compartment in an effective mann-er with minimum power and to deliver the earth to the storage compartment in a manner to utilize the f-ull capacity of the storage compartment and to favor the subsequent dumping operation. A feature of the preferred form of my invention is that the side Walls of the receiving compartment are fixed and that the scraper blade serves as the floor of the receiving compartment and is movable to lift the contents of the receiving compartment bodily into the storage compartment.

Another object in mind relates to the scraper In the preferred form of my invention, I propose, as above-stated, to have the blade perform the function of lifting earth bodily into the storage compartment of the scraper bowl. I propose to provide a blade design eifective for both of the two purposes served by the blade and to mount the blade in a. manner that will permit the required periodical loading movement and yet provide for the required vblade 'rigidity during the digging operation. In this aspect, my invention is characterized by a novel toggle arrangement to achieve the required characteristics of blade operation, and is further characterized by the conception of a blade .mounted on arms to function about a pivotal axis that is isolated from the earth being handled and, therefore, cannot be clogged or jammed by the earth.

In a scraper constructed to operate in the manner described above and having such a dualfunction scraper blade, it is desirable to insure that earth or rock will not cause the blade to jam to interrupt its. upward movement toward during initiation of the loading operation, and

the chocker member, and vto provide for automatic elevation of the chocker member to clear the ground when the scraper is ready for transportation of the excavated earth to the dumping area.

With reference to the unloading operation in the earth-moving cycle performed by the scraper, my object is torelease the material substantially directly under the center of gravity of the storage body to favor rapidity of dumping, and it is my further object to provide for carrying out the unloading operation with minimum power and ina mannerv to result in spreading the earth efficiently in a layer of adjustable depth.- A feature of the preferred form of my invention is the conception of a floor member for the storage compartment that is rotatively mounted to rock to selected dumping positions for spreading the earth to selected depths, the rocking operation being such as to consume relatively little power.

A further broad object of my invention is to provide a scraper of relatively little weight, simthe bowl and to insure that no substantial quan- -tity of earth will spill forward over the cutting edge of the upwardly-swinging blade to block the return downward movement ofthe blade. It is further desirable, for the sake of simplicity in the blade design and blade actuating mechanism, that the blade move in a simple path of reciprocation. Further objects of my invention lrelate to the attainment of these particular ends, and a feature of my invention is that such objects are accomplished by providing what I choose to call a chocker member or chocker box to cooperate with a pivotally-mounted scraper blade. The chocker member serves to deflect material into the receiving compartment of the scraper ple operation and inexpensive construction. This broad object is readily attained under the principles of my invention since only the scraper blade, the movable iioor member of the storage compartment and the chocker member are movable, the remaining elements of the scraper comprising e. rigid unitary structure connected directly to the supporting wheels.

Other objects, features, and advantages of my invention .will be apparent from my more detailed description to follow, taken with the ac companying drawings. y

In the drawings:

Fig. 1 is a side elevation of the scraper in digging disposition;

vFig. 2 is a plan view of the scraper;

Fig. 3 is a longitudinal section, taken along the broken line 3-3 of Fig. 2;

Fig. 4 is a fragmentary section on a somewhat enlarged scale, taken along theline 4--4 of Fig. 1;

Fig. 5 is an enlarged fragmentary section, taken along the line 5-5 of Fig. 1;

Fig. 6 isv a diagrammatic view on a reduced scale showing the scraper in the course of the meral I0 in the drawings, is an elongated receptacle fabricated from suitable metal plates and include side walls Il, a front end wall I2, and-a rear end wall I3, the front and rear end walls being arcuate, as shown,'for reasons that will be 'made apparent later.

supports and reinforces the bowl I0 is prefer- The frame structure that ably of hollow construction fabricated from steel member I surrounding thebowl near the top, a lower similar rectangular frame member I 6, and a pair of inclined frame members Hinterconnectingthe two rectangles at the rear corners of the bowl. A triangular assemblage of frame members, generallydesignated by the numeral I8, rigidly connected to the forward end of the bowl ID supports the bowl from la suitable pivotal connection with a forward axle assembly generally designated I9, the axle assembly being supported by forward wheels 20 and being provided with the usual draft tongue or draw-bar 2 I. At the rear end of the bowl, the supporting structure includes an assemblage of frame members, generally designated 23, that is connected to an axle 24 carrying rear wheels 25. Preferably, the side plates I I of the bowl extend somewhat above the level of the frame structure and are` reinforced by gusset plates 26 rising from the rectangular frame member l5. It will be noted that the described frame-and-bowl construction is rigidjthroughout. This eiicient, rugged, and yet relatively light construction is permissible because my invention does not require movement up and downof the bowl proper relative to the supporting wheels.

The preferred form of my invention includes a `transverse barrier, generally designated 29,

spanning the interior of the bowl I0, the barrier in effect dividing the bowl into a receiving compartment 3D and a storage compartment 3|.

The barrier 29 maytake various forms in various practices of my invention but in the specific form under consideration here is ,a hollow member having an arcuate forward wall 32, an inclined rearward wall 33, a bottom Wall 34, and side walls 35, the side walls, as best shown in Fig. 4, being spaced from and parallel with the corresponding side walls II of the bowl IU. The barrier 29 may be supported from the side walls II of the bowl I0 by an angle-iron 3l that extends across the bowl through the interior of the barrier near the lower rear edge thereof and by a second cross member, such asa bar 38.

My invention includes a blade assembly, generally designated 40, the essential parts of which are a scraper blade 4| and two support arms 42 that are rotatably mounted on corresponding pivot pins 43. The pivot pins43 are at each side of the barrier 29 and are on an axis concentric to both the curvature of the forward end plate I 2 of the bowl I9 and the curvature of the forward wall 32 of the barrier 29. The scraper blade 4l is so dimensioned and positioned that, asithe blade is swung upward, the forward or cutting edge of the blade follows the bowl wall I2 and the rearward edge of the blade follows the v barrier Wall 32. It is apparent that, by virtue 0f such a construction, upward movement of the blade 4I may be relied upon to lift the whole content of the receiving compartment bodily up- Ward over the barrier 29 into the storage compartment 3 l.

In the blade construction shown in the drawings, which is to be taken as suggestive only, the scraper-blade 4I is 'disposed at an angle relative to the arms 42 and the arms, which are of hollow construction and have overhanging upper walls 44, are continuous with corresponding reinforcement members 45 along each side of the blade,A

the reinforcement members tapering toward the leading edge of the blade. Side plates 46 that extend upward from each longitudinal edge of the blade 4I and are reinforced by bars 4'I and 4B lgive the blade assemblyv/the character of a struction laving av spaced lower plate 49 and is provided with a replaceable blade element 50 removably secured thereto by suitable bolts* 5I. It will be noted from Figs. 1 and 3 that the scraper blade 4I, in its cutting or excavating disposition, constitutes in eiect the bottom wall of thev receiving compartment 30. The blade may be said, then, to have three functions inasmuch as it serves as a digging member, 'forms a wall of the receiving compartment of the scraper bowl, andis movable to transfer the content of the receiving compartment into the storage compartment. By virtue of the overhanging walls 44, each of the arms 42` of the blade in eiect spans the corresponding space between the side lwall II ofthe bowl and the side wall 35 of the barrier 29, thereby forming a bottom for that space and also reducing the'likelihood Vof. earth or rock causing the arm to be jammed.

Various suitable mechanisms may be designed to actuate and control the scraper-blade 4I for the performance of the various functions mentioned above. In the preferred form of my invention, by way of example, I employ a toggle v v-concentric to the axis about which the arms rotate. On the far side of the scraper, as viewed in Fig. 3, the upper end of the toggle link 53 is pivotally connected to the lower end of a toggle arm 56 that swings on a pivot post 5'I mounted inside the frame member I5, the bottom of the frame member having a` slot (not shown) dimensioned to'clear the toggle 'arm at all positions. On the near side of the scraper bowl, as the bowl is vviewed in Fig. 1, the other of the two toggle links 53 is connected to a toggle arm 58 that is similar to the toggle arm 56, the toggle arm being in like manner mounted on a pivot post 59 in the frame member. I5. The toggle arm 58, however, is longer than the rst toggle arm 56 in that it has an end portion 60 extending above the frame member I5, the frame member having a lower slot 6I and an upper slot 62 to clear the toggle arm at all positions.`

On each side of the scraper bowl is a hydraulic jack 64 having its rear end pivotally anchored to and controlled through a pair of pipes 68 and flexible connecting conduits 69. It may be noted in Fig. l that, in thenormal digging disposition of the scraper blade 4l, the piston rod 66 of each of the hydraulic jacks is extended to its furthermost forward position, at which position theangle between the toggle link and toggle arm approaches a angle with a correspondingly highly favorable leverage ratio against the pivot post 54 on the scraper arm 42, It is apparent that onlya moderate thrust by the piston rod against the toggle linkage is required to hold the scraper blade at its lowermost position in a rigid manner that precludes chattering. If thehy draulic jacks yl/ en the opposite sides of the scraper are actuated to retract the piston rods ,66, the toggle links 53 are placed in tension to draw the scraper blade 4I upward and back to the extreme blade position indicated in Fig. 1 by a dashed line 10. Features of the described operating mechanism are, first, the effective locking of the scraper blade in digging disposition; second, the relatively extensive blade movement accomplished with only moderate movement of the piston rods; and, third, the relatively small range of oscillation on the part of the hydraulic jacks in the course of blade movement, this latter feature being important as minimizing the likelihood of objects adjacent the scraper interfering with the operation of the -hydraulic jacks.

Since material may spill out of the bowl through the arcuate slots 55 in the side walls Il, especially if the material is dry Vsandy soil, I add to the preferred form of my invention suitable closure means, such as an arcuate series of overlapping plates 12. Each of the plates is pivotally mounted ona bolt I3 and is pressed downward edgewise by a leaf-spring 'I4 against a stop pin 15, at which position the plate covers a portion of the slot. The various plates have forward and rearward edges inclined across the slot in the path of the pivot post 54'so that the blades are successively deflected by a cam action whenever the pivot post 54 traverses the slot in the course of scraper blade movement.

' In the preferred practice of my invention, it is contemplated that, periodically, the forward movement of the scraper will be interrupted for a loading operation, at which time the available power will be directed to the actuation of` two hydraulic jacks 64 to swing the scraper blade 4I upward and backward for transference of material from the receiving compartment 30 to the storage compartment 3|. It is desirable at such time that some means be provided to discourage the tendency of the loosened earth to spill forward over the leading edge of the scraper blade as the scraper blade is moving upward and approaches a position to cut off th'e lower end of the receiving compartment 38. lFor such purpose, I may provide what I call a chocker member, that is generally designated I'I in the drawings.- The chocker member is hingedly mounted and may be regarded as a yielding or flexible extension of the front bowl wall I2. AIn the preferred form of my invention, the chocker member TI is of hollow character, being in the form of a tray or box, and may, therefore, aptly be termed a chocker box. By virtue of this construction, the chocker member maybe loaded with ballast of selected weight vto provide a. de-

sired degree of inherent resistance to deflection.

In the construction shown in the drawings, the chocker box 11 has a rear wall 'I8 that is normally in approximate alignment with the bowl wall I2 and has a lower wall 19 that is arcuate in general configuration, the wall curving upward toward the front to encouragethe chocker box to ride over any rocks, earth ridges, or other relatively lowobstacles on the ground. The chocker box swings on a suitable pintle rod 80 and the lowermost rotativel position of the chocker box is `determined by a pair of adjustable chains 8l anchored to' a member` of the overhanging frame assemblage I8.

In the normal excavating disposition'of the scraper'shown in Figs. 1 and 3, the chocker box serves as a means to deflect material into the receiving compartment 30 or conversely as a baille to limit the forward displacement of earth loosened by the scraper blade. When the scraper is stopped for a loading operation, i. e.,- transference of material from the receiving compartment 38 to the storage compartment 3l, the upwardly-moving scraper blade acts as a lower jaw closing on the material at the entrance of the receiving compartment and the chocker box is, in effect, an upper jaw that is normally stationary yet is adapted to yield to any .unusual force. Under ordinary circumstances, the chocker box remains substantially stationary as the scraper blade moves upward and deilects the loosened earth into the receiving compartment 30, the chocker box cooperating with the scraper blade to close off the receiving compartment at a relatively low angle ofthe blade to prevent `earth from flowing over the blade from the receiving compartment. Should a rock, however, be entrapped between the scraper blade and the chocker box in the described jawaction, the up-- ward movement of the scraper blade will not be blocked nor will any damage be done because the chocker box will yield by swinging outward and upward to permit the rock to escape if the rock is too heavy to be deflected inwardby the resistance of the chocker box.

Since it is desirable for the chocker box to extend relatively close to the ground during digging operation, some means vshould be provided for swinging the chocker box to an elevated position when the scraper is used as a conveyance for transporting loaded earth to the dumping ground. A feature of my invention that the changes in position on the part of the chocker box required for digging and subsequent transportation may be accomplished automatically. For example, the chocker box may 4be operatively related to the scraper blade actuating mechanism in the manner indicated by the drawings. The toggle arm 58, the longer of the two toggle arms, carries a. rail 82 spaced in parallel relation thereto, the rail lying outside of the frame member I5 and being connected at its upperand Athe chocker box 11.

'lower ends to the toggle arm by websl83. The

rail 82 is loosely embraced by the two arms of a clevis 84 that carries a roller 85, the roller acting against the rear edge of the rail. A cable 86 connected to the clevis passes over pulleys 81, 88, and 89 to terminate in an anchorage fitting 90 On posed to pull forwardly on the clevis 84, the roller will automatically seek whichever en d of the rail is inclined forward. It will be noted that, since the upper end of the rail isA relatively close to the pivot axis of the toggle arm 58 as soon as the toggle arm is swung'rearward past vertical, the roller 85 will seek the upper end of the rail and then remain substantially stationary during the remaining rearward movement of the toggle arm.' In other words, the described arrangement is such that only initial movement of the toggle mechanism in elevating the scraper blade acts upon the chocker box 11. The'exact point in the cycle of toggle movement at which the chocker box will-begin to swing upward will depend upon the amount of slack in the cable and may be varied in the judgment of the operator in accordance with operating conditions.

Ordinarily, the upward movement of the chocker box should not be so prompt or rapid as to preclude the previously described cooperation with the scraper blade in cutting off the escape of loose earth from the receiving compartment.y

In the preferred form of my invention the side walls 92 of the chocker box converge inwardly Since the cable 86 is dis-- toward the leading end of the scraper bowl in spaced relation to side cutters 93 that extend forward from each side of the scraper bowl end. These side cutters areshown with replaceable cuttingfblades 94 disposed to divert material into the entrance of the scoop'assembly d0 and to cut clearance for the frame along `embankment slopes'.

The storage compartment 3i may be constructed in any manner or provided with any means known in the art to permit discharge of material therefrom. `One ofthe features of my invention, however, is a unique construction for the storage compartment that has outstanding advantages in the dumping and spreading of material. The xed walls 'of the scraper bowl i d form a bottom hole 96 in the storage compartment 3l that extends from one side'of the scraper bowl tothe other and from .the barrier 29 to the bottom edge of the rear wall i9 of the bowl. A doublewall door panel 9i normally spanning this bottom opening, as best shown in Fig. 3, is part of a dumping cradle, generally designated 99,@ the dumping cradle irluding two triangular side plates 99 that lie y ,closely adjacent to the corresponding side walls H of the scraper bowl. For strength, the edges ofthe side plates99 may be bent to form linclined marginal anges 900. The cradle 98 is 'rotatively carried by a pair of pivot pins l| that extends through the material of the corresponding side walls Il of the scraper bowl' andthrough adjacent portions of the frame member l5. Preferably, the curvature of the rear wall i3 of the scraper bowl has 4the same axis as the two pivot pins I0i so that thevrear edge of the floor panel 91 will follow the bowl wall I3 to loosen earth therefrom when thecradle is rocked rearward to release earth from the storagecompartment 3l. It will be further noted, as best shown in Fig. l, that the marginal flanges |00 of the triangular side plate 99 of the cradle are disposed to scrape away any material adhering to the bowl Walls Il, such scraping action being part of the cradle operation.

While any suitable means may be provided for actuating and controlling the cradle 98; I prefer to use a second pair of hydraulic jacks |03 mounted on the opposite outer side of the scraper bowl I0. Each of the'hydraulic jacks 03 is pivlotally mounted on a bracket plate |04 and is connected to a pair of hydraulic lines |05. Forwardlyextending piston rods |06- of the hydraulic jacks 'are pivotally connected to corresponding pins l01 that extend outwardly from each of the cradle side plates 99 through'suitable arcuate slots |08 in the side walls H of the scraper bowl. Both the hydraulic jacks |03.for

viously-mentioned hydraulic jacks 6I for operat ing the scraper blade 4l are energized by power means to which the scraper is coupled and are subject to remote control by suitable valves' (not shown) within reachof the tractor operator, a plurality of hydraulic conduits H0 interconnect-v ing the tractor and scraper for such purpose.

The operation of my invention. may be readily understood from the foregoing description. 'In the normal digging disposition ofthe various movable parts, best shown in Fig. 3, the blade Il is at its lowermost position' to dig 4into the soil. The

chocker box "I1 is relatively close tothe ground level Iand is disposed to facilitate crowdingof the loosenedsearth into the receiving comparty ment 30. When. ,a substantial quantity of -earth accumulates `in. the receiving compartment, as

shown diagrammaucauy in rig. s, 'the driver win cause a loading operation to be carried out.v The driver may stop the forwardmovement of the' as indicated at l@ in Fig. il and shown. diagram,- matically in Fig. V"Z, being such as to cause substantially all the earth carried thereby to drop into the storage compartment 9i. y

After a few loading operations, the storage compartment 9i accumulates a capacity load and the final loading operation will consist merely in lirtingthe scraper blade di sufliciently to close the` lower end of the receiving compartment 30 effec= tively without causing any substantial displacement of the earth upward in the receiving compartment. Although thisnal closing movement of the scraper blade 4i is not extensive, the operative connection with the chocker box i7 is ,suchl that the closing movement of the blade causes the chocker box to swing upward and the scraper is then ready to transport a capacity load to a dumping area, the disposition of the various movable parts being as indicated diagrammatically in Fig, 8.

To release the material from the storage oompartmfent 8i at the dumping ground, the operator manipulates the proper valve control to cause movement of the cradle to the rear causes the operating the dumping cradleA 98 and ,the' prel the hydraulic jacks |03 to retract the piston rods Mid, thereby causing the cradle 98 to swing rearward as diagrammatically shown in Fig. 9.- It is to be particularly noted that' this rearward rocking of the cradle provides an exceptionally extensive opening immediately under the center v of mass of the earth piled in the storage compartment 3l, so that the weight of the material has maximum eect on expeditlng the discharge from the -scraper bowl. It is to be further noted that the depth to which the discharged material is spread on the dumping ground is determined byl the extent to which the cradle is rocked. .It is apparent from an inspection of Fig. 3 that initial leading edge ofthe floor panel 91 to approach the ground level, but that, in the latter p'art of the cradle movement, the leading edge of the cradle Vincreases its distance from the ground level. Ad-F justment of the depth to which the material isv spread may be controlled, then, either within the earlier range of cradle movement in which the leading edge ofthe fioor panel approaches thel groundlevel or in the later range in which the.

leading edge retreats from the ground levL Preferably, the cradle is moved to operatein thelatter range to provide an opening of 4maximum effective size for gravitation oil the material-to the ground, such alarge opening being especially advantageous for sticky soil that will not spread thin easily. Thus, forspreadingthedischarged earth in a relatively thin'layer, the floor panel- 91 may be swung to Van intermediate'position Il i,` shown in ydashed line in Fig. 3, and. ior'spreading` `a layer of maximum ,thickness may be swung upward completely into the bowl to the dashed yline position IIZ. When the storageoompartmentll is empty or nearly empty, the operator energzes the hydraulic jacks Et to swing the scraper blade lil vupward for the purpose of transferring to the Astorage compartment 3i that portion of the load that was transported to the dumping ground in the receiving compartment Zio. At the end of the dumping operation, the operator causes the various parts to return to the traveling positions shown in Fig-8, and the scraper is returned to the excavation area to repeat the ground-moving cycle.

My disclosure in specic detail of the preierred bottom opening; and a scraper blade adapted to dig earth and to divert the loosened earth upward through said opening, said blade being mounted on pivot means spaced rearward from said opening and being adapted to swing upward and rearward through .said opening' into the interior of said bowl to displace accumulated earth rearward from said opening, one of said walls conforming -to the arcuate path of the outer swinging edge of said blade, and another of said walls conforming to the inner swinging edge of said blade to prevent the escape of any substantial quantities of earth past said edges as the blade is swung upward past said opening.

2. In an earth-moving machine of the char acter described, the combination of t Va bowl having a bottom opening to receive earth; a scraper blade pivotaily movable from' a digging disposi-z tion below said bowl into a position closing said opening; and a baiiie means yieldingly mounted forward of said opening to cooperate with the swinging leading edge of said scraper blade in closing said opening.

3. A' combination as set forth in claim 2 in which said baille means is of a configuration to extend forward as well as downward from said opening to divert loosened earth into the open- 4. In an earth-moving machine of the character described, the combination of: a bowl inav-a Aing when said blade is in digging disposition.

ing a bottom opening to receive earth; a scraper clearing position when said blade is lifted to close said opening for transportation of a load in the bowl.

5j In an earth-moving machine of the character described, the combination of; a bowl having a forward bottom opening; a scraper blade adapted to take a lower position belowsaid openn ing to dig earth, or an intermediate position to close said opening, o'r to moveto an uppermost position to displace accumulated earth from above said opening; means movabiy mounted on said bowl adjacent the front edge of said opening to cooperate with said blade in directing earth amasar into said opening; power-actuated means to lift the blade from said lower position either to said intermediate position or to said uppermost posi tion.; and automatic means to elevate said mow ably mounted means for ample ground ciearance when said blade is elevated to said intermediate position to close said opening for load transportation.

6. In an earth-moving machine of the charm acter described, the combination of: a scraper bowl having a forward bottom opening and a rearward bottom opening; a transverse barrier across said bowl between saidvopenings dividing the bowl into a receiving compartment and a storage compartment; a scraper blade adapted to take a' lower position below said forward opening to dig earth, or an intermediate position to close said forward opening for transportation, or to move to an uppermost position to force the content of said receiving compartment over said barrier into said storage compartment; means normally covering said rearward opening and movable therefrom to permit dumping there through; and power means to move said scraper blade and covering means.

7. An earth-moving machine of the character described having in combination: a storage compartment; a vertically extensive transverse wall spaced forward from said storage compartment; side walls extending forward from said storage compartment to said forward transverse wall; an upwardly extending rearwardly curving wall between said side walls and spaced rearward of said first-mentioned wall, said curving wall leading to said storage compartment;' a bottom wall extending forward from said curving transverse wall, said` two transverse Walls, said side walls, and said bottom wall forming a. receiving compartment forward of said storage compartment, said bottom wall being adaptedfor digging and diverting earth into said receiving compartment; and power-actuated means to lift said bottom wall to carry material up the forward face of said curving transverse wall into storage compartment.

8. An earth-moving machine of the character described having in combination: a storage cornpartment; a rst transverse wall spaced 'forward from said storage compartment, said'transversev wail being curved with an axis of curvature rearward therefrom; side walls extending forward from said storage compartnientl to said transverse wall; a second transverse wall spaced rearward of said rst transverse wall and forward of said axis, said second transverse wall being curved concentric to said axis; a bottom wall ein7 tending forward from said second transverse.

wall, said rst and second transverse walls, said side walls, and said bottom wall forming a receiving compartment, said bottom wall being movable upward between said transverse walls and between said side walls in a path concentric to said axis to transfer material from said re= ceiving compartment to said storage compartment; scraper means at the forward edge of said bottom wall; and power-actuated means to move said bottom wall upward periodically.

9. An earth-moving machine of the character described having in combination: a ,receiving compartment having front, rear, and side walls;

a separate storage compartment having front,v

rear, and` side walls; a movable scraper blade normally at the bottom of said receiving ,comn partment in a position to direct earth from below into said receiving compartment; and power said upward into said receiving compartment toA transfer earth from the receiving compartment to said storage compartment.

10. An earth-moving machine of the character described having in combination: a receiving compartment closed at the sides and open at the top; an adjacent storage compartment open at the top; a barrier separating said compartlments; a relatively movable lower wall normally in a fixed position forming `the bottom of said receiving compartment adapted to move upward to displace earth in the receiving compartment over said barrier into said storage compartment; and power means to actuate said movable wall periodically Awhen earth accumulates in said receiving compartment to substantially ll the receiving compartment 11. An earth-moving machine of the character l described having in combination: a receiving compartment having a rear wall, side walls, and an upwardly and rearwardly curving -front wall; a storage compartment to the rear of said receiving compartment; a scraper blade positioned to serve as a bottom wall of said receiving compartment, said scraper blade being mounted to swing upward in a rearwardly curved path along the inner face of said front curved wall of the receiving compartment to move material from the receiving compartment into said storage compartment; and power means to actuate said scraper blade.

12. An earth-moving machine of the character described having in combination: a scraper bowl having a bottom opening; a scraper blade adapted to dig earth and crowd the loosened earth upward through said opening; means pivotally supporting said blade from a point spaced from saidv Y opening and adapted to carry said bladeiin an arcuate path upward through said opening into the bowl to displace earth accumulated above the opening; and wall means separating the path of movement of said blade-supporting means from the interior of said bowl to prevent earth in the bowl' from interfering with the pivotal movement of said blade-supporting means.

scraper blade pivotally movable from a digging position upward through said opening into the bowl to displace earth accumulated above the opening; a toggle-linkage operatively connected to said scraper blade for raising and lowering the blade, said toggle-linkage being above the diggingposition of the scraper blade and adapted to take a position of vmaximum leverage when said blade is in digging position whereby the toggle-linkage preventschattering of the blade during digging operation; and power means to actuate said toggle-linkage and thereby said blade. Y 15. An earth-moving machine as set I:forth in claim 14 in which lsaid toggle mechanism includes an arm pivoted to swing about a fixed axis near its upper end, and includes a link pivoted to the lower end of said arm, said link being connected Ito said blade, and in which said power means exerts its actuating force rearward to raise the blade. v

16. An earth-moving machine of the character described having in' combination: a storage compartment; a vertically extensive transverse wall spaced forward from said storage compartment; side walls extending forward from said storage compartment to said transverse wall; an' upwardly and rearwardly extending transverse wall between said side walls and spaced rearward from said rst-mentioned transverse wall, said upwardly and rearwardly extending transverse wall leading to saidV storage compartment, said two side walls and said two transverse walls forming a receiving o compartment 4forward of said storagel compartment; a blade element disposed to loosen earth from the ground towards the forward) end of said receiving compartment; wall means rearward of said blade element normally 13. An earth-moving machine of the character 'v described having in combination: a scraper bowl having a bottom opening: a blade normally in a digging position below said bowl to crowd' earth f upward through said opening; movable means y supporting said blade and adapted to carry the blade bodily upward throughsaid opening to disvplace accumulated earth from above said opening; and walls adjacent the edges of said blade conforming to the path of said upward movement disposed to serve as a bottom for saidreceiving compartment and to direct earth loosened by said blade element into the receiving compartment, said wall means being movable upwardly; and power meansoperatively connected to said wall means to lift the wall means and thereby force earth up said upwardly and rearwardly ex-4 tending transverse wall into said storage comhpartment. Y i 17. In an earth-moving machine, the combina Ation of; a bowl having a bottom opening; a

to prevent any substantial quantity of earthnto' escape downward past the upward moving blade afterthe blade through said'opening, one

of said walls serving as a barrier to divide the' bowl into a receiving compartment and a storage compartment. 14. In an earth-moving machinathe combina- `tion of: a bowl having a bottom opening; 'a

scraper blade pivotally movable from a digging position upward through said opening into the bowl -to displace earth accumulated above the opening; a toggle-linkage operatively connected to said scraper blade for raising and lowering the blade, said toggle-linkage being above the digging position of the' scraper blade and adapted to take a position of maximum leverage against lsaid blade. whenthe blade is in digging position;

and a hydraulic ram adapted to actuate saidtoggle-linkage'for raising andlowering the blade and adapted to exert continuous pressure on the toggle-linkage at the lower position of the blade to prevent chattering ofthe blade during digging operation.v`

- l LEO BERNER.