US3276152A

US3276152A - Submarine scraper

Info

Publication number: US3276152A
Application number: US343872A
Authority: US
Inventors: Knap George
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-02-10
Filing date: 1964-02-10
Publication date: 1966-10-04
Anticipated expiration: 1983-10-04

Description

G. KNAP SUBMARINE SCRAPER Oct. 4, 1966 4 Sheets-Sheet 1 Filed Feb. 10, 1964 INVENTOR GEO R G E K NAP ATTORNEYG Oct. 4, 1966 G. KNAP 3,276,152

SUBMARINE SCRAPER Filed Feb. 10, 1964 4 Sheets-Sheet 2 INVENTOR GEORGE KNAP BY ATTORNEYI:

Oct. 4, 1966 G. KNAP 3,276,152

SUBMARINE SCRAPER Filed Feb. 10, 1964 4 Sheets-Sheet 5 INVENTOR GEORGE KNAP mmwk/k ATTORNEYS Oct. 4, 1966 v G, KNAP 3,276,152

SUBMARINE SCRAPER Filed Feb. 10, 1964 4 Sheets-Sheet 4 3,276,152 SUBMARINE SCRAPER George Knap, 4408 Wildwood Crescent, Burnaby, British Columbia, Canada Filed Feb. 10, 1964, Ser. No. 343,872 8 Claims. (Cl. 37125) This invention relates to earth moving scrapers particularly to the type which are drawn by cables operated remotely from the scraper itself, a function which makes this type of scraper peculiarly adapted to submarine evacuation.

Earth movers of the cable drawn type are usually constructed having a bucket or bowl with a cutting edge at its fore end to dig into the earth as the scraper is drawn thereover and to lower the bucket into the body of the scraper. When the scraper reaches the end of its forward travel, means are provided, operated by the control cable to empty the bucket of its contents. The bucket is then returned by means of a haulback cable to the digging site from which point the scraping cycle again commences.

In certain scrapers, the cutting edge of the bucket remains in a digging position throughout the entire forward travel of the scraper, however, this method is wasteful of power as the cutting edge of the scraper is continually digging into the ground. Certain earth scrapers have been developed to overcome this problem by providing a means operable by cables to lift the cutting edge of the bucket from the ground after the bucket is filled, thereby decreasing its resistance to forward motion. Most of the scrapers of this latter type are quite complicated in construction and operation. They are, therefore, by reason of their complexity, not adapted for simple rugged construction, and may therefore be easily damaged if the operator is not extremely careful in this matter of operation.

The present invention overcomes the above difiiculties by providing an earth scraper which, simple of operation and construction, and which automatically moves from a digging position to a carrying position when loaded in order to permit the earth to be carried with the expenditure of minimum power. This invention also provides an earth scraper which automatically discharges its load when the operator commences to return the scraper to the digging site. The automatic features of the present invention permits earth moving operations to be carried out by operators of little expericen and due to its simplicity of construction may be ruggedly constructed to stand very roughh-andling during its digging operations.

The present invention comprises a chassis having a haul forward cable secured at its fore end and a haulback cable secured at its aft end, wheels on the chassis to support the scraper for movement over the ground, a bucket mounted on the chassis in an fore and aft position, said bucket being movable between a normal digging position, a carrying position and a dumping position, a cutting edge on the fore end of the bucket which, in the latter digging position, extends below the ground and in the carrying position lies above the ground, means connecting the bucket and said haul forward cable to move the latter from its normal position to its carrying position as tension is applied to said haul forward cable to move the scraper over the ground, means connected to the bucket to retard the movement from the digging position to the carrying position as the scraper is moved forwardly, said mean being timed to retain the cutting edge in its position extending below the surface of the ground for the bucket to dig into and sutficiently fi ll itself with earth before said cutting edge is carried above said surface, and dumping means operable by applying tension United States Patent 3,276,152 Patented Oct. 4, 1966 to the haulback cable to move the bucket into its dumping position.

In order to provide lateral movability of the scraper, whereby earth may be excavated from the disposed over a large area, the wheels upon which the chassis are mounted are castered, and the haulback and haul forward cables are so arranged that the direction of pull on the scraper may be varied at the will of the operator to thereby vary its path to and from the area in which the earth is excavated and dumped.

In the drawings which illustrate embodiments of the invention,

FIGURE 1 is a plan view of the scraper,

FIGURE 2 is an elevation of one embodiment of the scraper showing, in solid lines, the bucket in its carrying position and in dotted lines the bucket in its stopping position,

FIGURE 3 is an end elevation of the embodiment as shown in FIGURE 2,

FIGURE 4 is a fragmentary side elevation showing another embodiment of the scraper in positions similar to FIGURE 2 FIGURE 5 is a fragmentary section taken on the line 5-5 of FIGURE 4,

FIGURE 6 is an isometric view partially in section of a portion of the apparatus whereby the movement of the bucket from its digging to its carrying position is retarded,

FIGURE 7 is an exploded isometric view of the caster wheel support,

FIGURE 8 is a fragmentary isometric view of an alternate embodiment of the caster wheel support as shown in FIGURE 7,

FIGURE 9 is a diagrammatic representation of a typical cable and winch arrangement to move the scraper, and

FIGURE 10 is a diagrammatic representation in elevation showing the scraper in various positions throughout its path of travel, and also showing the bucket in its digging, carrying and dumping positions.

Referring to the drawings, one form of earth moving scraper generally numbered 10, as shown in FIGURE 1, 2 and 3, comprises a chassis 11 mounted on wheels 12, said chassis serving as a support for a bucket 13. The bucket 13 is arranged for movement of the chassis between various positions, as shown in FIGURE 10, whereby it may be lowered to a digging position fill itself with earth, raised into a position whereby it may be easily transported and then tipped into a dumping position to discharge its contents.

The chassis 11 is essentially a rigid frame having a pair of spaced parallel

longitudinal side members

14 and 15, and spaced parallel fore and aft

transverse members

16 and 17, respectively. The farming members are welded together at the corners to present an extemely rigid framework.

Bucket 13 which is rectangularly shaped and elongated in a fore and aft direction, is formed as a scoOP having

side walls

18 and 19, a bottom 20, and a rear wall 21. The fore edge of the bucket is provided with a cutting blade 23 which lies in a horizontal frame transversely to the longitudinal axis of the bucket. The

side walls

18 and 19 are each provided near their fore ends with outwardly projecting

pintles

25 and 26, which are adapted to pivotally and slidably ride in vertical slots 27 and 28 formed in a pair of plate-like supporting

members

31 and 32, respectively, which depend downwardly from the

longitudinal members

14 and 15, respectively, near the fore end of the scraper, the connection between the supporting members and said longitudinal members being made by welding or the like. The pintles project outwardly of the outer faces of the supporting

members

31 and 32, and their ends 33 and 34, respectively, may be riveted to bear on said outer faces of the supporting members to prevent withdrawal of the pintles through the slots, therebyirestraining lateral movement of the bucket relative to the chassis 11. By referring to FIG- URE 2 it will be sen that the slots are of sufficient length, that with the

pintles

25 and 26 at the lower extremity of the former, the cutting blade 23 of the bucket will lie below the surface of the ground, and when the pintles are at the upper extremity of the said slots, the said cutting blade will lie above the ground. Also it will be noted that the bucket 13 is free to pivot on the pintles, whereby the bucket 13 may be disposed from a position as shown in solid lines in FIGURE 2 to a position as show in dotted lines in the same figure.

The fore end of the bucket 13, due to the weight of the bucket, will normally assume a position in which the

pintles

25 and 26 are at the lower ends of the slots 27 and 28. The fore end of said bucket is therefore-secured to the haul forward line 40 through a retarding mechanism 42, whereby upon the application of tension to said line, the pull will be transferred to the bucket to lift the forward end thereof, the

pintles

25 and 26 sliding upwardly to the upper ends of slots 27 and 28.

The retarding mechanism 42 comprises a piston 43 mounted for reciprocation in a cylinder 44, the latter being mounted in a fore and aft direction for oscillation in the vertical plane between brackets 45 fixed to the forward transverse member 16 of chassis 11 centrally thereof.

The cylinder 44 is provided at its after end with a head 47 having an aperture 49 formed centrally therein, said aperture being provided with a suitable gland 51. The gland is of sufficient size to slidably and sealably receive a rod 52, one end 55 of the rod being connected to the piston 43 and the other end of the rod 56 being pivotally connected to a lever 58, the latter being secured fixedly intermediate of the ends of a transverse bar 59 which is journalled for rotation in bearing blocks 60 secured to the

longitudinal members

14 and 15 of the chassis 11.

Near the ends of the transverse bar 59 are secured for rotative movement therewith a pair of levers 61, the latter being coupled to the

pintles

25 and 26 by vertical rods 62 and 63, respectively.

The forward end of the cylinder 44 is provided with a head 65 and gland 66 adapted to slidably receive a rod 67. One end 68 of the rod being secured to the fore end of the piston 43, the other end projecting forwardly beyond the gland 66. The walls of the cylinder 44 are extended forwardly beyond the head 65 and serve as guides fora piston-like runner 70, the latter being secured to the rod 67 near its other end 71. The cylinder 44 is also provided with a bypass conduit 73, said conduit communicating at each end thereof with the interior of the cylinder near each of the

heads

47 and 65. Said conduit providing a means whereby hydraulic fluid with which the cylinder is filled may be transferred from one end to the other dependent upon the movement of the piston 43. The conduit 73 is also provided with a valve 75 which may be manually adjusted I control the rate of flow of fluid from one end of the cylinder 44 to the other. The valve may be of any type needle or gate, to provide the necessarily fine regulation of flow of hydraulic fluid.

In the scraper 10 the after end of the bucket 13 is connected to a pair of substantially vertical stanchions 78. The stanchions are pivotally connected at their lower ends to a transverse shaft 79 which is secured between a pair of supporting members 81, which depend downwardly from the after transverse member 17, being secured thereto by welding in order to ensure rigidity. The stanchions are formed as yokes at their upper ends in which sheaves 83 are journalled for rotation.

The bucket 13 is connected to the stanchions by means of sleeves 84 sl-idable on the stanchions and having a pivotal connection as at 85 with the rear end 21 of the bucket, said sleeves permitting elevation of said bucket from a position as shown in solid lines in FIGURE 2, to the dumping position as shown in dotted lines in the same figure. Another transverse shaft 87 is supported for rotation between the supporting members 81 and carries a winding drum 89 centrally thereof and fixedly secured for rotation in unison therewith. A pair of smaller drums 91 are also fixedly secured to the shaft for rotation therewith on either side of the drum 89. Cables 92 extend from each of the drums 91 over the sheaves 83 and are secured as at 93 to the bucket 13. The haulback line 95 is secured at one end to the drum 8?, being wound around in such a manner that upon tension being applied to the haulback cable to rotate shaft 87, the drums 91 Will rotate thereby winding cable 92 thereon and elevating the bucket 13 to its dumping position as shown in dotted lines in FIGURE 2. It will be appreciated that upon release of tension to the haulback line 95, the bucket, due to its weight, will return to its position as shown in solid lines in FIGURE 2, thereby unwinding cables 32 from drums 91 and winding the haulback cable on drum 89.

In accordance with the objects of this invention, it is the purpose to provide a scraper which may be guided by altering the lateral direction of pull of the haulback cable to permit the operator of the scraper to dump the contents thereof over a relatively large area. The wheels 12 of the scraper are therefore connected to the chassis in a manner whereby they will caster.

It is apparent that if a type of caster were used whereby the wheels would have to rotate on a vertical axis a full 180 in order to provide lateral movability of the scraper to and from its dumping area, the

longitudinal members

14 and 15 would have to extend sufiiciently far enough beyond the fore and aft ends of the bucket 13 to provide suflicient clearance. A scraper constructed in this manner necessitates the provision of long and consequently heavy side members and will result in a unachine having an excessive overall length compared to the length of the bucket. It would also result, due to the fact that the wheels would have to swivel about their vertical axis for approximately 180 every time the direction of movement of the scraper were reversed, in excessive wear of the rolling contact surface of the wheel. In the operation of the scraper, only :a minimum amount of caster of the wheels about a vertical axis is necessary, for steerage. The forward wheels of the scraper, and the rear wheels if desired, are secured to the chassis on a caster mechanism which permits the mechanism to reverse its caster upon the reversal of the direction of movement of the scraper without necessitating the wheels to be rotated 180 about the vertical axis. The caster arrangement also provides for a minimal swivelling action of the castered wheels about the vertical axis sufficient to permit a minimal amount of steerage.

In accordance with the present inventon, the chassis 11 is provided at each corner thereof with a passage extending vertically therethrough, welded to the underside of the chassis at each corner is a bearing plate 162 with an aperture 103 lying in registry with said vertical passage. Said aperture and passage are adapted to receive an elongated boss or pintle 104 formed on the upper surface 105 of a bearing member 106, said pintle extending above the upper surface of the chassis to accept retaining means. In this example, pintle 104 is threaded and drilled to accept a nut 107 and cotter pin 108. Any retaining means will suffice, which keeps pintle 104 engaging passage 100.

The lower end 1111 of the bearing member 106 is bifurcated, the lower surface of the bearing member lying between the bifurcations being shaped to form a pair of outwardly diverging downwardly facing shoulders 112. The said lower end 1111 is adapted to receive the upper end portion 113 of a wheel supporting bracket 114, the

latter being pivotally secured between the bifurcations of the said lower end 110 on a horizontal shaft 115. The upper end portion 113 of the bracket is formed with angular shoulders 117, each of which is so arranged that it will engage one of the corresponding shoulders 112 upon the bracket being tilted a few degrees on either side of its truly vertical position. The bracket 114 is provided with a shaft 118 at its lower end thereof upon which one of the wheels 12 is rotatably mounted. It will be apparent that the arrangement foregoing has given the desired caster effect to the wheel 12, whereby the directionv of caster thereof may be reversed without the necessity of rotating the said wheel 180 about its vertical pivotal axis.

It is apparent that the castered wheel as described is freely pivotal through 360 on the boss or pintle 104, and in certain circumstances dictated perhaps by the manner in which the'scraper is to be employed, this type of caster may be advantageously used. However, where only limited lateral movement of the scraper is desired, the pivotal movement of the caster may be limited. This may be accomplished, as indicated in FIGURE 8, by forming an elongated slot or indentation 126 on the periphery of the bearing plate 102 to form spaced shoulders 128 to serve as stops for a dog 130 projecting upwardly from the upper surface 105 of the bearing member 106. The slot or indentation 126 may be made as long as necessary to provide a spacing between shoulders 128 sufficient for the desired rotation of the caster wheel about its vertical axis.

In the operation and use of the scraper to dig, carry and subsequently discharge the earth from the bucket, reference should be had to FIGURES 1, 2 and of the drawings. In position A or digging position, both the haul forward and haulback lines are slack, thereby permitting the bucket, by its weight to assume a position in which the forward edge of the bottom thereof lies below the surface of the ground to be excavated and the after end of the bucket is in its non-elevated position, the cable 92 being wound on drums 91. Tension is then applied to the haul forward cable to move the scraper forwardly, the forward edge of the bottom of the bucket cutting into the earth to fill the bucket. Simultaneously with the forward motion of the scraper, the fore end of the bucket, being linked to the haul forward line through the retarding mechanism 42, lifts upwardly until the forward edge of the bottom thereof is above the surface of the ground, the scraper assuming its carrying position, as indicated by the letter B. It will be appreciated that the upward movement of the forward end of the bucket may be regulated by the valve 75 of the retarding mechanism 42, whereby .said upward movement may be correlated with the forward movement of the scraper so that the forward edge of the bottom 20 of bucket will not rise above the surface of the ground until the bucket has been filled with earth.

The scraper is then moved forwardly by means of the haul forward cable until the scraper has reached its dumping point. The haul forward cable is then slacked off and the haulback cable taken in. The forward end of the bucket will drop to the surface of the ground and the haulback will rotate drum 91, thereby rotating transverse shaft 87 to which drums 93 are secured, and winding up cables 92 to elevate the after end of the bucket, the scraper assuming a dumping position as indicated by the letter C 0n FIGURE 10 to permit the earth carried by the bucket to be discharged from the open front end thereof. The scraper, of course, is then moved rearwardly by the haulback line to its excavating site.

FIGURE 9 indicates one manner of cable arrangement which is especially suitable for sub-marine excavation and which provides a degree of lateral control of the scraper. In this figure, a cable 132 secured to the chassis of the scraper at the rear end thereof and passed around a pulley 133 which is secured to an anchored float 136. The cable 132 is then carried to a windlass 137 on shore and which 6 is powered by any suitable source of power, not shown. The cable is then passed around a pulley 138 which is secured to the end 71 of rod 67 in the manner .shown in FIGURE 6, then passed around pulleys 139 and 140 anchored on shore fixed to a powered winding drum 142.

Both the winding drum 142 and windlass 137 are provided with controls whereby the amount of cable payed out and taken in by each may be correlated a transverse as well as fore and aft pull on pulley 138 to move the scraper laterally as well as longitudinally. When lateral force is applied to the said pulley, the force is transferred to the scraper unit through the runner 70 acting on the walls of the cylinder 44, thereby relieving any lateral strain which would ordinarily be applied by the rod 52 against the gland 51.

It is to be understood that the operation of the scraper is not limited to the arrangement as shown in FIGURE 7, said figure showing only one arrangement which will provide lateral as well as longitudinal movement of the scraper.

FIGURES 4 and 5 indicate an alternative form of scraper 160. Scraper is constructed in the same manner as scraper 10, the only difference lying in the manner in which the bucket is elevated at its rear end and in the manner in which the front end thereof is suspended. In scraper 160, the bucket 162 is pivotally and slidably secured to supporting members 163 and 164 in the same manner as bucket 13 of scraper 10 is secured to supporting

members

31 and 32 thereof. Supporting members 163 and 164 are pivotally secured at their upper ends to a shaft 166, the latter being secured between the longitudinal members herein numbered 168 and 169 of the chassis 170.

Side walls 171 and 172 of bucket 162 are extended rearwardly beyond the rear wall 173, the projecting portion 175 and 176 each being provided with an arcuate slot 178 and 179 extending from near the top to near the bottom thereof. Secured to the end wall 143 of the bucket 162 and parallel to the slots 178 and 179, are a pair of elongated gear racks 180 and 181 which are adapted to mesh with gears 183 and 184 fixedly secured to a shaft 185 which extends through the slots 178' and 179 and are rotatably secured at each end thereof to longitudinal members 168 and 169 of the chassis 170. The shaft 185 also carries, inwardly of gears 183 and 184, sprockets 187 and 188 fixedly secured thereto for rotation in unison therewith.

A transverse shaft 191 is secured for rotation between a pair of supporting members 193 and 194 secured to the chassis much in the .same manner as are supporting members 81 and 82 of scraper 10, and has fixedly secured thereto for rotation in unison therewith, a central drum 195 to which the haulback cable 196 is secured in the same manner as the haulback cable is secured to drum 91. The shaft 191 has also fixedly secured thereto for rotation in unison therewith a pair of sprockets 198 and 199, each of which is operatively connected to sprockets 187 and 188, respectively, by chains 201 and 203, respectively. In the operation of scraper 160, it will be seen that when tension is applied to haulback cable 196 to rotate drum 195, transverse shaft 191 will rotate thereby rotating sprockets 198 and 199. The rotation of the latter sprockets will in turn rotate sprockets 187 and 188, thereby rotating shaft 185 and gears 183, and 184, the latter rotating against the gear racks 180 and 181, respectively, to elevate the bucket 162. When tension on haul-back cable 196 is relieved, the weight of the bucket 162 will allow it to return to its lower position, thereby counter rotating sprockets 187 and 188, the rotative movements of the latter being transferred to the drum 195 to rewind a portion of the haulback cable 196 thereon.

During the elevating and lowering of the after end of bucket 162, the forward end of the bucket is free to swing on the pivoted support members 163-164 thereby 7 eliminating any tendency of the shaft 185 to bind in the slots 178 and 179.

What I claim as my invention is:

1. An earth moving scraper comprising a chassis, Wheels on which the chassis is supported for movement in a fore and aft direction over the surface of the ground, an earth carrying fore and aft bucket having a cutting edge at its fore end slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between a first position in which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable from a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a haul-in cable secured to the scraper at its fore end to move the latter forwardly, means connecting the fore end of the bucket and said cable and operable upon tension being applied to said cable to move said fore end from its normal position towards its second position, retarding means connected to the bucket to retard the latter movement, said retarding means being adjustable to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, a haulback cable secured to the after end of the scraper to pull the latter rearwardly, and bucket dumping means connecting the haulback cable and the after end of the bucket operable as tension is applied to the haulback cable, to elevate said after end above the fore end to thereby dump the load.

2. An earth moving scraper comprising a chassis, wheels on which the chassis is supported for movement in a fore and aft direction over the surface of the ground, an earth carrying fore and aft bucket having a cutting edge at its fore end slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between a first position on which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable from a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a transverse shaft journalled for rotation in the chassis, a first lever fixedly connected to the transverse shaft whereby the latter may be rotated, a second lever connected at one end to the transverse shaft for rotation therewith and linked at the other end to the fore end of the bucket whereby upon rotation of the shaft the bucket may be moved from its first to its second position, a haul-in cable connected to the first-mentioned lever to simultaneously rotate the shaft and move the scraper forwardly, retarding means connected to the fore end of the bucket to retard the movement of the latter from its first to its second position as the shaft rotates, said retarding means being adjustable to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, and a haulback cable secured to the after end of the scraper to pull the latter rearwardly, bucket dumping means connecting the haulback cable and the after end of the bucket operable as tension is applied to the haulback cable, to elevate said after end above the fore end to thereby dump the load.

3. An earth moving scraper comprising a chaisss, wheels on which the chassis is supported for movement in a fore and aft direction over the surface of the ground, an earth carrying fore and aft bucket having a cutting edge at its fore end slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between a first position on Which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable rom a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a haulin cable secured to the scraper at its fore end to move the latter forwardly, means connecting the fore end of the bucket and said cable and operable upon tension being applied to said cable to move said fore end from its normal position towards its second position, retarding means connected to the bucket to retard the latter movement, said retarding means being adjustalble to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, said retarding means comprising an elongate-d hydraulic cylinder connected to the chassis, a fluid by-pass passage providing communication between each end of the cylinder, a piston in the cylinder movable from one end to the other thereof and having a connection at one end with the fore end of the bucket, said piston being adapted upon being moved between said ends of the cylinder to transfer the hydraulic fluid from one end to the other, and a regulating valve in the passage whereby the rate of flow of the fluid through the passage may be controlled to thereby control the rate of movement of the piston, and a haulback cable secured to the after end of the scraper to pull the latter rearwardly, bucket dumping means connecting the haulback cable and the after end of the bucket operable as tension is applied to the haulback cable, to elevate said after end above the fore end to thereby dump the load.

4. An earth moving scraper comprising a chassis, wheels on which the chassis is supported for movement in a fore and aft direction over the surface of the ground, an earth carrying fore and aft bucket having a cutting edge at its fore end slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between a first position on which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable from a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a haul-in cable secured to the scraper at its fore end to move the latter forwardly, means connecting the fore end of the bucket and said cable and operable upon tension being applied to said cable to move said fore end from its normal position towards its second position, retarding means connected to the bucket to retard the latter movement, said retarding means being adjustable to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, a transverse shaft secured for rotation on the chassis at the after end thereof, a first winding drum secured to the chassis for rotation therewith, a haulback cable Wound on the winding drum to rotate the latter upon tension being applied to the former, a second winding drum secured on the shaft for rotation in unison with the first, and a second cable connected at one end to the after end of the bucket and wound on the said second winding drum, whereby upon tension being applied on the haulback cable to rotate the first drum and thereby rotate the second drum, the said second cable will be wound on the second drum thereby drawing the after end of the bucket to its upper position to thereby dump the load, said bucket returning to its normal position upon release of tension on the haulback cable to rotate the shaft and rewind haulback cable on the first drum.

5. An earth moving scraper comprising a chassis, wheels on which the chassis is supported for movement in a fore and aft direction over the surface of the ground, an earth carrying fore and aft bucket having a cutting edge at its fore en-d slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between .a first position on which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable from a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a haul-in cable secured to the scraper at its fore end to move the latter forwardly, means connecting the fore end of the bucket and said cable and operable upon tension being applied to said cable to move said fore end from its normal position towards its second position, retarding means connected to the bucket to retard the latter movement, said retarding means being adjustable to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, a transverse shaft secured for rotation on the chassis at the after end thereof, a first winding drum secured to the chassis for rotation therewith, a haulback cable wound on the winding drum to rotate the latter upon tension being applied to the former, a substantially vertical gear rack secured at the after end of the bucket, and a gear fixedly secured to the shaft for rotation in unison therewith, said grear meshing with the gear rack to move the latter upwardly when the former is rotated as tension is applied to the haulback cable to thereby elevate the bucket to its upper position and to dump the load therefrom, said bucket being adapted to return to its normal position upon release of said tension on the haulback line to rotate the shaft and rewind the haulback cable on the drum.

6. An earth moving scraper comprising a chassis, caster wheels in which the chassis is supported for movement in a fore and aft direction over the surface of the ground, said caster wheels providing a means whereby the chassis may be directed laterally, an earth carrying fore and aft bucket having a cutting edge at its fore end slidably and pivotally secured at its fore end and after end to the chassis for vertical movement of said fore end between a first position on which the cutting edge extends below the surface of the ground to a second position in which said cutting edge lies above said surface, said bucket being normally biased by weight thereof to said first position, said after end being movable from a normal weight-biased lower position to an upper position in which said after end is elevated above the fore end, a haul-in cable secured to the scraper at its fore end to move the latter forwardly, means connecting the fore end of the bucket and said cable and operable u-pon tension being applied to said cable to move said bucket from its normal position towards its second position, retarding means connected to the bucket to reard the latter movement, said retarding means being adjustable to correlatedly time the upward movement of the cutting edge with the forward movement of the scraper to permit the bucket to load itself before the cutting edge is lifted out of the ground, a haulback cable secured to the after end of the scraper to pull the latter rearw ardly, and bucket dumping means connecting the haulback cable and the after end of the bucket operable as tension is applied to the haul-back cable, to elevate said after end above the fore end thereby dumping the load.

7. An earth moving scraper as claimed in claim 6 in which the caster wheels each comprises a bearing mem' ber .pivotally connected to the chassis for rotation about a vertical axis, an elongated bracket having a wheel carrying axle secured at one end and hingedly secured at the other end to the bearing member for pivotal movement about a horizontal axis, shoulders formed on the bracket on both sides of the latters pivotal axis, and stops formed on the bearing member and lying in the path of the shoulders as the bucket is rotated about its horizontal axis, said stops and shoulders being spaced apart to permit rotation of the bracket in an arc of predetermined length extending on both sides of a position in which the wheel axle lie-s vertically below the pivotal axis of said bracket.

8. An earth moving scraper as claimed in claim 7 in eluding means to limit the rotation of the bearing member about its pivotal axis.

References Cited by the Examiner UNITED STATES PATENTS 1,017,293 2/1912 Johnson 37135 1,242,320 10/1917 Burkett 37-135 2,873,871 2/1959 Waite 371 16 ANTONIO F. GUIDA, Primary Examiner. W. A. SMITH, III, Assistant Examiner.