US3049823A - Excavating machines - Google Patents

Description

Aug. 21, 1962 R. v sPALDlNG EXCAVATING MACHINES 4 Sheets-Sheet 1 Filed Feb. 2l, 1961 n Etm x w oop mustn am R nNw wv` m42- 2.5.x m N M N L R m E A O IHN ,m WHMM V @lv mmh m iv E E M R .vm Fm D Aug. 21, 1962 R. v. sPALDlNG EXCAVATING MACHINES 4 Sheets-Sheet 2 Filed Feb. 2l, 1961 'mum-mummy* 33 INVENTOR 81 13 Foefer l( JID/suma;l

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ATTORNEYj Aug- 21, 1952 R. v. sPALDlNG 3,049,823

EXCAVATING MACHINES Filed Feb. 2l, 1961 4 Sheets-Sheet 3 E925 s H94 3 25' 'HILH Y INV ENTOR I f 21 [Posner V. Smm/fvg 39 40 3a ATTORNEY) Aug. 2l, 1962 R. v. sPALDlNG EXCAVATING MACHINES 4 Sheets-Sheet 4 Filed Feb. 2l, 1961 INV ENTOR ROBERT l( SPAIIYLu//vs' IOO 43 16.87

v f n v I \Y/ A BY ATTORNE` United States This invention relates to excavating machines which include conveying and discharging means for the excavated material.

An important object of the invention is to provide an excavating machine which includes a wide and deep mouth opening at the excavating end portion of the machine for receiving excavated material removed by portions of excavating' means which project outwardly beyond the mouth at the sides of the mouth and which is relatively narrow as compared to the width of the mouth, whereby a large amount of material may 'be excavated by the machine since its movement is not impeded by portions of the excavating teeth-carrying means or a narrow mouth.

Another important object is to provide an excavating machine wherein the excavated material-moving flights are so positioned that their movements within the mouth of the machine is only impeded in a limited way by friction of the ights set up by contact thereof with the excavated material. The ights immediately deposit the excavated material upon novel pick-up and dumping means, which is immediately next to the flights.

A further important object is to provide novel pick-up and dumping means which includes flexible members which, cooperating with main longitudinal structural side frame members of the machine, provide baskets of initial substantially J-shape but each of which, upon receiving a load of excavated material from the flights, assumes a substantially U-shape and, upon reaching a material dumping location, atten out quite tautly and discharge the load, whereupon the flexible members fold into a narrow formation, less than the U-shape, for passage to the initial position and shape detailed above. Thus, the machine frame may be of less size than would be the case were the baskets rigid and maintained their shape during passage through the machine.

An additional object is to provide substantial hinge connection means between the exible members of the excavated material pick-up and dumping means and portions of the excavating means as well as portions of the conveyor means of the machine.

A further additional object is to provide dual function portions of the machine, such as pivotal connections between the flights, the ilexible basket-forming members and chains of the excavating means, whereby the number of parts of the machine may be reduced without any reduction of functions of the machine. Others of the dual function portions are the main longitudinal structural side frame members of the machine which also function as side walls for the exible basket forming members and also protections and guide for portions of the movable elements of the excavating means, since these side frame members are partly hollow and receive such last-named portions, protecting them against contact with the walls of an excavation and the excavated material being moved by the conveyor means of the machine.

Other objects and advantages of the invention will be apparent during the course of the following detailed description of the invention, taken in connection with the accompanying drawings, forming portions of this disclosure, and in which drawings:

FIG. l is a side elevational `view of one form of the excavating machine of this invention, shown by yway of example, and mounted upon a support, shown as a tractor.

FIG. 2 is a front elevational view thereof.

FIG. 3 is a vertical sectional view substantially on the arent Of ice line 3 3 of FIG. 2, but on an enlarged scale over that of FIG. 2.

lFIG. 4 is a fragmentary vertical sectional View, substantially on the line 4 4 of FIG. 3.

FIG. 5 is a fragmentary horizontal sectional view, substantially on the line 5 5 of FIG. 3.

FIG. 6 is a fragmentary horizontal sectional View, substantially on the line 6 6 of FIG. l, but on an enlarged scale over that of FIG. l.

IFIG. 7 is an elevational view of connection means between conveyor chains and a flight belt.

FIG. 8 is a fragmentary elevational view of a connecting means between an endless belt and conveyor chain of the machine.

FIG. 9 is a fragmentary sectional view, substantially on the line 9 9 of FIG. 8.

FIG. 10 is an enlarged fragmentary sectional view, substantially on the line 10 10 of FIG. 1 but on a scale enlarged over that of FIG. 1.

FIG. ll is an elevational view of connection means between an endless belt and a flight belt.

FIG. l2 is a fragmentary sectional Iview, substantially on the line 12-12 of FIG. ll.

FIG. 13 is a fragmentary sectional View, substantially on the line 13 13 of FIG. 7.

FIG. 14 is a fragmentary vertical sectional view, along the lines of the lower portion of FIG. 3, showing a modication thereof.

FIG. l5 is a horizontal sectional view substantially on the line 15 1-5 of FIG. 14.

lFIG. 16 is a vertical longitudinal sectional view substantially on the line 1(5 16 of FIG. 7.

In the drawings, wherein for the purpose of illustration are shown two embodiments of the invention and wherein similar reference characters designate corresponding parts throughout the several views, the letters A and B designate two forms of the invention, the letter C a support, shown by way of example, for either the machine A or B, D a chute for receiving excavated material discharged from the machine A or B, and connection means E between the machine A and support C for carrying and orienting the machine A.

The machine A preferably comprises a frame 20 supporting excavating means 3i), drive means 50 for the excavating means 3b, conveyor means 60, excavated material pick-up and dumping means 80, and an excavated material discharge wiay 100, receiving the material from Ithe means 80.

The Iframe 20 is shown, by way of example, to comprise two substantially parallel main longitudinal structural side `frame members 2l, and transverse structural cross frame 'and support member-s 22 and 23, connecting the members Z1 `and lsecured thereto as by welding, by way of example. Each member 2.1 is preferably provided with combined guide and guard walls, defining openings, as slots 24 (FIG. 4) -therein at the excavating end portion of the machine A, and slots 28 at the head portion of the machine A, all for accommodating portions of the excavating means 30` iof the machine A, as will be more fully described later. In addition, these members 21 are provided with openings, Ithe Walls of which deiine recesses 25 and `26 ("FIG. 4) extending inwardly from the inner lfaces 27 of the members 21 for accommodating portions of the excavating means as well as portions of the conveyor means which will be explained subsequently.

It will be noted in FIG. 3 that the length of the chain 31 (being one of the pair of chains` 31) substantially parallels the edges of the member 21 and is closely adjacent 4these edges, the chain being disposed within the slots 2.4.

Supported or carried by the frame 20 is the excavating 4integral parts of the :chain linkage.

4 bers 21.

-ilexible means as, for example, a pair of excavator chains 31. Attachments, as will be described, Aare made as Preferably, the chains 311 are conventional conveyor-type industrial chains.

Al first pair of excavator chain sprocket wheels 32 or their equivalent, is provided, over which the excavator chains 3-1 are trained and which wheels are accommodated in the slo-ts 24 and are xedly mounted, as by conven- Ational splines or keys, on first stub shafts 33, carried by the members 21 in suitable bea-rings and retained again-st undesired longitudinal movement by suitable means, such as nuts 34 and 35, with the last accommodated in the recesses 26, so as not lto interfere with ythe operation of the conveyor means. The outer lends of the stub shafts extend outwardly of the outer faces of the members 21 for support of excavator Wheels or discs 3S which will be described later.

The excavator chains 31 are also trained over a second pair of excavator chain sprocket Wheels 36 (FIG. 5) `at the head portion of the machine A, being rotatably carried by the members 21 upon second stub shafts 37, and accommodated in the slots 28. 'Ille Wheels 36 may be keyed or splined on the shafts 37 and the latter earried by suitable bearings of the members 21. It Will be noted that the shafts 37 extend outwardly of the members 21 for support of portions of the drive means 50 to be described later.

Mounted upon the outer end portions of .the first stub shafts 33 are a pair of excavator Wheels or discs 38 which may be conventionally keyed or splined -to .the shafts 33 to rotate with the sprocket Wheels 32. These Wheels or discs 3S preferably carry a plurality of spaced-apart pro jections or lteeth 39 which are rigid therewith and extend radially loutwardly of the periphery of the wheels or discs, providing means to gouge, splinter, cut or break a formation or body of material with which they come into contact upon rotation of the excavator wheels 38 as is Well known in the art. Portions of the projections or -teeth project Well outwardly o-f the planes of the edges of the excavating end portions of the members 21, as may be appreciated from FIGS. l, 2, 3, 4 and 14. Thus a good excavating action is assured.

Referring particularly to FIG. 6, there is shown a pair of first excavator chain direction guide sprocket wheels 40 for lthe chains 31, which wheels 46 are mounted upon stub shafts 41 carried by the members 2l, with the wheels 40 disposed in the recesses 24. Referring now particularly to FIG. l0, there is shown a pair of second excavator chain direction guide sprocket wheels 42 for the chains 31, which Wheels 42 :are mounted in spacedapart relation upon a shaft 43 journaled in the mem I prefer to provide also a pair of third excavator chain direction guide sprocket wheels 44 (FIG. 4) mounted in spaced-apart relation, for free turning on shaft 4S, which is carried by the members 21. The wheels 44 are contained in the slots 24 and mount the chains 31.

A suitable number of ilights 46 are provided, such as illustrated, by way of example, in FIGS. 3 and 7 and carried by the chain-s 31. These flights 46 may have the leading cutting edges 47, and trailing edges 48.

Drive means 50 for the excavating Ameans 3G may include, for example, an electric motor l which may be rigidly mounted upon the cross member 23 and be provided with -a drive pulley 52, such as a V-'belt drive pulley, upon which is trained a belt 53 such as a Vabelt trained about a driven pulley 54, such 'as a V-belt driven pulley xedly mounted upon a jack shaft 55. This shaft also at one of its end portions, with a pillow-block bearing 57 for the shaft 55 preferably interposed between the wheel xedly mounts a first drive sprocket Wheel 56 preferably l 56 and driven pulley `54. The shaft 55 also mounts a second drive sprocket wheel 56 preferably at its other end portion with a second pillow-block bearing S7 interposed between it and the driven pulley S4. The pillow-block bearings 57 may be rigidly mounted upon the members 21. From the wheels 56 drive chains 58, trained thereupon, extend to .and around driven sprocket wheels 59 which are mounted upon (such as keyed thereto) stub shafts 37 which latter, as heretofore stated, iixedly mount the second pair of excavator chain sprocket wheels 36.

Conveyor means 66 for the excavated material is preferably carried by the frame 20 and includes a flexible member, preferably an endless belt 61 Without any direct drive, being rotatable by the pull of the flight belt 81 and connection means 83 and 84 between the cha-ins 3l of the yexcavating means 30 and belt 61 as will be more fully detailed later. The belt 61 may be trained about a tail pulley or rolle-r 62 which is mounted, for free rotation, on the shaft 45 which latter is carried by the members 211. Preferably at the end portions of the pulley or roller 62 are sprocket teeth 63 which engage the chains 64 (FIGS. 8 and 9). These chains (there are tw-o of them shown by way of example) are preferably of the conventional endless industrial convey-or type and are attached lto the belt 61, preferably adjacent the side edges thereon.C (FIGS. 8 and 9) by a plurali-ty of spacedapart belt-to-chain securing means 65, each comprising a plate portion 66 secured to the belt as by rivets 67, and secured to Ithe chain links as by an offset portion 68 which also 'forms a portion of the chain linkage and attached thereto by the pivot 69. It will be noted, such as in FIG. 3, that Athe endless belt 61 substantially parallels the faces 27 of the members 21.

The conveyor means 60 also preferably includes a head pulley or roller 70 (FIG. 6) about which the belt 61 and chains 64 are trained. The pulley or roller 70 is mounted for free rotation upona shaft 71 carried by the members 21. The pulley or roller 70 is provided, at its end portions, With sprocket teeth 72 to engage the chains 64.

ln addition, the conveyor means 60 includes a plurality of spaced-apart intermediate support rollers 73 disposed in spaced relation between the pulleys or rollers 62 and 70, and which pulleys 73 are rotatably supported on shafts 74 mounted on the members 2.1. These rollers 73 support the chains 64 and belt 61 for rotation thereof.

Referring mainly to FIG. l0, it will be seen that I prefer to provide, as part of the conveyor means 60, a pair of sprocket wheels 75 each carried by a stub shaft 76 rotatable in suitable conventional bearings in the members 21. The teeth of the Wheels 7S engage with the chains 64 and also function as direction guides for the belt 61 as it passes downwardly toward the tail pulley 62.

Now, with special reference to the excavated material pick-up and dumping means of the conveyor means 60, I provide a plurality of flexible flight belts or material supports 81, as best shown in FIG. 3. These belts are constructed and arranged to pick up, as the chains 31, carrying the flights 46, and belt 61, rotate clockwise, in the example shown, excavated material, as the latter enters between the excavator wheels 38, moves upon the lowermost flight belt 81, and is carried upwardly, by the ilight belt and dumped yat the upper end portion of the machine A, whereupon the belt 81 passes downwardly in a collapsed condition and then reassumes its pick up shape at the bottom portion of the machine. It will be noted that the shape of the belts 81 are in substantially scoop or basket positions where the excavated material enters the machine A with the belt surface $2 uppermost. The belts 8l maintain these scoop or basket positions as they ascend, then turn over into somewhat taut positions, with the belt surfaces 82 facing downwardly. This ability to turn over .and become somewhat taut is due to the locations of the coupling means 83 and 84 connecting the belts 81 respectively with the flights 46, carried'by the chains 31,' and belt 61, and the location of the axis of Iotation of the shaft 71 and diameter of the head pulley 70 with respect to the axis of rotation of the shaft 37 and diameters of the sprocket wheels 36 mounted thereon as is now apparent from FIG. 3.

The coupling means 83 is best shown in FIGS. 7 and 13, and comprises a hinge assembly which preferably is a hinge leaf 35 secured, as by rivets 86 to the belt 81, projecting partly beyond the edge of the belt and hingedly connected as by a second hinge leaf 87 to `a flight 46 at the trailing edge portion thereof. The pivotal connection 87' may connect both the leaf 87 to the flight 46 and flight 46 to the chains 31.

The coupling means 84 is best shown in FIGS. 1l and 12, and comprises a hinge assembly which preferably is a hinge leaf 90 which is secured to the endless belt 61 and a hinge leaf 91 secured to the flexible flight belts 8l at one end portion of each of the latter. There is provided a pintle or pivot 92 for connection of the hinge leaves 90 and 91. The leaves may be connected to the several belts by rivets 93 and 94 or `the like.

An excavated material discharge way 160 may be provided at the upper end portion of the machine A, for receiving the material from the means `60, with the way 100 communicating with an opening or mouth 101 and projecting downwardly and outwardly. This way may communicate with a discharge chute D, being coupled thereto in any approved way such as by conventional nut and bolt means 102.

The connection means E. Ibetween the machine A 'and support C for carrying and orienting the machine A may be of any approved kind and is no part of the invention, being shown by way of example. It may include pairs of hydraulically or pneumatically operated pivoted telescoping supports 105 and pairs of arms 1616, pivotally carried by the support C and pivotally carrying the machine A by the members 21, with the lower end portion 107 of the Iarm 106 pivotally connected ywith a plunger rod 108 of a piston-and-cylinder assembly 109.

Operation of the machine A is as follows:

The machine may be lowered or thrust into the material to be excavated. Prior to this operation the electric motor 51 has been energized and the flights 46 are thus caused to move around the periphery of their path defined by the course of the endless chain-s 31 passing around their respective sprocket wheels. During intervals between passing of the flights down and around the sprocket wheels 32 the excavator teeth 39 effect a digging action cycle which, coupled with thrust of the machine, will bring material from the bite, between the side frames 21, the excavator wheels 38 being locked in rotation with the sprocket wheels 32. One flight now advances downwardly, engages with the sprocket teeth of Wheel 32 and is pulled through the excavated material and upwardly. As the flight moves upwardly, the excavated material is deposited in the lowermost basket formed by the flexible basket-forming support 81. The inner substantially parallel faces 27 of the members 21 prevent the major part of the excavated material from escaping out of the basket. As the flight 46 continues upwardly the excavated material is confined between the belt 6l and the basketforming support, and the pull on `this belt 61 through the coupling means 84 causes it to travel around its respective pulleys. The center line spacing of the excavator chain sprocket Wheels 36, with respect to the head pulley 70 is such that when the basket-forming support 81 reaches the common axis of the sprocket wheels 36, it is drawn substantially taut and the excavated material is spilled out, through the discharge way 100, into the chute D. In the meantime the opposite flight 46 has partially completed an excavation cycle and is starting upwardly. At this -stage of operation the movement of the belt 61 around its pulleys will be substantially halted until the flight performing the excavation cycle moves upwardly a distance sufficient to tighten the corresponding support 81 and its pull again starts the belt 61 traveling. This period of non-rotation of the belt 61 will allow the then uppermost flight 46 to travel downwardly past the head pulley 70 and lead the corresponding `support 31 downwardly towards its next excavation cycle. Two excavations flights 46 and supports 81 have been illustrated, but mo-re may be employed as is obvious. The size of the machine and its application will determine the number of flights and their pitch distance. `It is important that the pitch spacing of flights be such that as a lowermost flight is making the excavation cycle, at the same time another flight is going through the discharge cycle. This arrangement allows the lowermost coupling means 84, at the excavation location, not to advance until the corresponding flight has passed through the bite of the material being excavated and to begin its upward movement.

Referring now to FIGS. 14 and 15, Where the modifications of the machine A are illustrated to provide the machine B, a comparison of FIG. 14 With FlG. 3 will show that the only substantial changes reside in substituting for the sprocket wheels 44, other sprocket wheels preferably similar to sprocket wheels 75 in order that the chains 116 (preferably similar to the chains 31) may pass around sprocket wheels 115 and the flights 117 (preferably like the flights 46) and supports 11S (preferably similar to the supports S1) associated with the flights 11'7 and endless belt 119 in the same way as are the supports 81.

Of course, the machine B operates in the same way as does the machine A.

Placing the excavator wheels 38 at the exterior sides of the members 21 of the frame 2f), rather than at the interior sides thereof, affords a wider mouth to receive the excavated material which, in turn, affords a wider passageway of the excavated material through the machine.

Attachment of flight or flights 46 to the chains 31 are made as an integral part of the chains linkage. That is, as shown in FIG. 7, the parallel link pins 49 of two adjacent links of the chains extend into suitable parallel sockets in the side portions of the flight 46. Thus, the flights, after they have scooped up the excavated material and it moves upon the flight belts, will move into a path, with their transverse axes upwardly-extending and form a wall to retain the material upon the flight belts during the upward journey of the latter. Thus, the flights have plural functions.

It will be noted that elements, such as the shaft 4S which mounts the third sprocket Wheels 44 and the toothed tail pulley 62 has plural functions. The shaft 71 and sprocket wheels 75 also have plural functions as described.

The flight belt or belts 81 may be of any suitable material depending mostly upon the weight and/ or condition of the excavated material. They may be of stout fabrics such as wire or cloth, or of leather, for example, but it must be readily flexible. The word belt is ernployed, for the element 81, in the broader sense and not as an endless strap or band around two or more wheels. The belt or belts 81 are such as are adapted to take the scoop form while receiving and supporting the excavated material, the substantially taut form while discharging the material, and the folded form while passing through the restricted space between the endless belt 61 or 119 and the chains 31 or 116. As hitherto pointed out, this last permits a narrowing of the frame 20.

Various changes may be made to the forms of the invention herein shown and described without departing from the spirit of the invention or scope of the claims.

What is claimed is:

l. An excavating machine, including a frame, excavating means carried by said frame, endless chains carried by said frame and operatively connected with said excavating means to cause operation of said excavating means, and conveyor means carried by said frame, for receiving and conveying excavated material excavated by said excavating means, including an endless belt rotatable in a path inwardly of the runs of said endless chains and vspaced from said endless chains, and an excavated mate- Vrial receiving scoop of flexible material operatively carried at one end portion of said scoop by said endless chains to move therewith and carried by said endless belt at the other end portion of said scoop.

2. An excavating machine, including a frame having side Walls, excavating means carried by said side walls, and conveyor means, carried by said side members, for receiving excavated material from said excavating means, including an excavated material receiving scoop comprising a sheet of flexible material extending across said machine to closely adjacent said side walls, and a Eight extending across said machine, having a trailing edge connected with one end portion of said sheet and providing a barrier against the escape of excavated material from said one end portion of said sheet.

3. An excavating machine including a frame having two substantially parallel main longitudinal side frame members, the lower extremity of said members defining an excavating end portion of said machine and an excavated material receiving mouth, and the upper portion of said members defining an excavated materials discharge mouth; excavator means carried by said members including excavator sprocket chains, sprocket wheels adjacent the members mounting said chains, excavator teeth operatively connected with said chains, means for guiding said chains in obtuse angular paths between said sprocket wheels; conveyor means carried by said frame including a ight mounted between said chains for receiv ing excavated material at said excavated material receiving mouth; an endless belt spaced a relatively short distance from a portion of the downward path of said chains, and spaced a relatively greater distance from the upward path of said chains, a flexible flight belt tor receiving excavated material from said Hight, said flexible iiight belt extending across the space between said members and secured at one end to said endless belt and secured at the other end of said flexible Hight belt to said i'light, the length of said iiight belt being such that it will form a scoop when at said excavating end portion and during the upward paths of said chains and endless Hight belt, will flatten out when adjacent said excavated material discharge mouth to discharge said material therein, and will fold when moving in the space between the downward flight of said endless flight belt and the downward flight of said chains where said endless iiight belt and chains are spaced said relatively short distance apart.

4. An excavating machine according to claim 3 characterized in that the connections between said iiexible iiight belt and said endless -belt and between said flexible flight belt and said flight are hinge connections.

5. An excavating machine according to claim 3 characterized in that said iiight has a leading cutting edge and extends with its transverse axis and leading cutting edge upwardly during the upward path of said flexible ight belt, whereby said flight provides a wall against egress of excavated material from said iiexible night belt during movement of said flexible flight belt on said upward path. l

6. An excavating machine according to claim 5 characterized in that said ilight is disposed with its ends closely adjacent said members, whereby said members also provide walls against egress of excavated material from said ight belt during movement of said flexible ilight belt on said upward path.

7. An excavating machine including a frame having two spaced-apart substantially parallel main longitudinal side frame members defining a space Ibetween said members, an excavating end portion and an excavated material discharge portion, said members having outer edges;

a pair of spaced apart endless chains, rotatably supported, one chain being rotatably supported by one ot said members and the other chain being rotatably supported by the other of said members, both being adjacent the edge portions of said members; means for rotating said chains carried by said members; rotatable excavator means carried by said members, disposed at said excavator end portion and operatively connected with said chains for rotation of said excavator means; and conveyor means including an endless belt rotatably supported by said members within said space and with its side edges adjacent one like edge portion of both members, remote from the other edge portions thereof and extending to said discharge end portion, and a ilexible flight belt extending across said space and having opposite ends, with one of said ends operatively connected to said chains and the other of said ends carried by said endless belt.

8. An excavating machine including a frame having two substantially parallel facing and spaced apart main longitudinal structural side frame members defining a space between them, each member being provided with two spaced-apart continuous openings, each extending inwardly from its inner face and disposed inwardly of the edges of said members, one opening in one member facing a like opening in the other member; rotatable excavating means carried by said member, endless chains and sprocket wheels therefor disposed within the lirst-named openings and operatively connected with said excavating means to rotate said excavator means, excavator flight means carried by said chains and movable in said space to receive material excavated by said excavating means; endless sprocket chains and wheels therefor disposed within the second-named openings; an endless lbelt carried by the last-named chains and extending across said space to adjacent the second-named openings and substantially paralleling a portion of the iirst-named chains; a flexible ight belt connected at one end portion of the tlight means and connected at its other end portion to said endless belt to move through said space in a looped formation', said iiight and endless flight belt provide a support for excavated material from said excavating means.

9. An excavating machine according to claim 7 characterized in that said excavating means includes at least one excavator flight extending across said space to closely adjacent said members and provided with a pair of sockets in each side portion thereof and with a leading edge and a trailing edge, and said endless chains include a plurality of links and link pins connecting adjacent links, with some of said link pins extending into said sockets.

10. An excavating machine according to claim 7 characterized in that the longitudinal axes of said members extends upwardly, said endless chains and endless belt move in spaced-apart upward and downward pathsa tlight having a trailing edge is carried by said chains, said flexible ight belt carried at one end thereof by the trailing edge of said tlight, said endless conveyor chains and endless conveyor belt isA relatively disposed so that said flexible ight belt will form a scoop for the excavated material during only the upward path of travel of said iexi-ble flight belt, and said light additionally provides a wall for retaining excavated material while said ilexible flight belt is in it upward path.

References Cited in the tile of this patent UNITED STATES PATENTS 287,563 Morton Oct. 30, 1883 328,697 Marquis Oct. 20, 1885 981,440 Llewellyn Ian. 10, 1911 1,679,143 Wineman July 3l, 1928 2,858,755 Toulmin Nov. 4, 1958 2,956,668 Fioravanti Oct. 18, 1960

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