US2826839A - Roller conveyor for excavating wheel - Google Patents

Description

March 18, 1958 F. F. KOLBE 2,826,839

' ROLLER CONVEYOR FOR EXCAVATING WHEEL Filed Nov. 6, 1953 s Sheets-Sheet 1 INZENTOR. jFarzflI/[oda BY W I March 18, 1958 F. F. KOLBE ROLLER CONVEYOR FOR EXCAVATING WHEEL 3 Sheets-Sheet 2 Filed Nov. 6, 1953 March 18, 1958 F. F. KOLBE ROLLER CONVEYOR FOR EXCAVATING WHEEL 3 Sheets-Sheet 3 Filed Nov. 6, 1953 INVENTOR. flaizffiblbe BY fi/ HM I I 5% q: M

United States Patent ROLLER CONVEYOR FOR EXCAVATING WHEEL Frank F. Kolbe, Winnetka, Ill., assignor to The United Electric Coal Companies, Chicago, Hit, a corporation of Delaware Application November 6, 1953, Serial No. 390,454

4 Claims. (Cl. 37-190) The present invention relates generally to excavating apparatus of the bucket wheel type and particularly to an improved roller conveyor for transferring excavated material from the interior of the wheel to a belt type conveyor or the like.

In excavating apparatus of the type referred to, a large rotatably mounted wheel is provided with a plurality of buckets attached to its periphery that cut into and scoop up a quantity of earth when the Wheel is rotated. The buckets carry the earth upward to a point where the earth gravitates therefrom into the interior of the wheel. Some means must be provided to receive the earth and convey it from the interior of the wheel to a belt type conveyor or the like which is usually disposed adjacent the wheel and parallel thereto.

In the past it has been the practice to provide an inclined slope sheet, extending from the interior of the wheel toward the belt conveyor, which received the earth and fed it either directly onto the conveyor, or fed it to a point adjacent to the conveyor whereupon a suitable mechanism or manual labor were utilized to place the earth on the conveyor. However, the use of a slope sheet has several disadvantages (all of which my invention overcomes), among which are the following;

(1) In order that dirt may slide off of the slope sheet, the slope sheet must be placed at a substantial angle. For

example, in an existing wheel of 20 foot diameter and with buckets 32 inches wide,the inclined slope sheet has its top inside edge 4 feet 9 inches above the center of the axle and'that reduces the space interiorly of the Wheel into which material may be discharged. When the material is packed into the bucket by the excavating action, it usually will not discharge'until the tail of the bucket has passed the top inside edge of the sheet which is 4 feet 9 inches above the axle; has not only a reduced space into which to discharge but also short dumping range until the far side of the slope sheet is reached. Consequently, either the Wheel must be run more slowly to give suflicient time forall the material to get out or the wheel must make a light out so that the material is not too closely packed bucket.

(2') Owing to the fact that the slope sheet is at a coninto the siderable angle, rocks or frost lumps falling, onto it are but little retarded and are likely to hitthe conveyor belt as substantial velocity withresulting damage to the belt. Also, the rocks or lumps may bounce oif the belt and strike other portions of the excavatingmechanism. Since theirocksand lumps will generally discharge only as the bucket reaches its highest position the impact slope sheet and belt will be considerable.

(3) For a 'given size of wheel one'can have buckets of on the The bucket therefore only a certain width; which is relatively narrow, since I the slope sheet must go from the outside of the bucket across the interior ofthe wheel to the other side of the wheel and must be at a considerable angle, Hence, the

height that the slope sheet can go controls the; distance 2,326,839 Patented Mar. 18, 1958 tive to the horizontal, the material, of course, will not slide off.

(4) Also, on a slope sheet sticky material builds up and this requires some form of cleaning mechanism which is subject to wear and is something of a main tenance item.

Therefore, it is a primary object of this invention to provide an excavating wheel having an earth conveying means which eliminates the necessity for having an in ternally disposed slope sheet, and which feeds the excavated earth out of the wheel to some means for removing same, all with greater efficiency than prior conveyors have provided and without the above disadvantages.

It is a more particular object of this invention to provide an excavating wheel having roller conveyor means for receiving the earth which gravitates toward the interior of the wheel from the buckets, and which efficiently conveys the earth exteriorly of the wheel toward and onto a belt type conveyor or the like disposed adjacent said wheel.

In accomplishing the foregoing objects by my invention, the earth is brought out from the inside of the Wheel by a series of rollers which are normally arranged horizontally, although they canbe arranged at a slight downward incline toward some external conveying means such as an endless belt or the like. The highest point of such rollers in a 20 foot wheel, for example, may be only 30 inches or less above the center of the axle. This gives a materially longer arcuate distance through which the buckets may dump. Also, since the rollers are lower in the wheel than a slope sheet would be, there is more space into which the material can dump. a

For example, in an existing 20 foot-wheel, the buckets are approximately 4 feet deep. The tails are there fore set on a 12 foot circle. If the rollers are setapproximately 2 /2 feet above the center of the axle, the tails are not clear until they have risen 2 /2 feet, but are then free for approximately the next 3 /2 to 4 feet vertically and tail of the bucket is completely free for only item 3 inches going up and another 1 foot 3Iinches going down, or a total of 2 feet 6 inches. Measured in degrees, in the use of the roller conveyor of my invention, the tails are free for approximately while in using'the slope sheet the tails are free only 74. it is possible, therefore, to speed up the action of the wheel and increase its excavating capacity; V

Furthermore, the rollers being horizontal or at only a slight angle, a rock falling from the highest position of the bucket strikes aflat bed of rollers which absorbs the impact and then is transported by the rollers to a conveyor belt, or the like, instead of striking the belt with considerable impact, as has been the case with a slope sheet.

Since the rollers in my invention are set low, the material can come out of the buckets before the buckets have raised very much above the center of the'axle and t is held back by the margin of the'slope sheet and then'it" all tends to come out at once, producing an impact and uneven loading.

A further advantage of my invention is that the material in the bucket of a wheel with a bed of horizontal rollers; falls'in a vertical plane parallel with the wheel. The

entire width of the bucket is uncovered at once. A slope sheet, on the other hand, by the very fact that it is sloping, does not uncover the whole width of the bucket at once. A part of the bucket is uncovered and then another part, and so on, as thebuckets rise. The material diIectly back' of the central opening of the Wheel (that is, the material spaced the farthest laterally from the slope sheet) tends to fall out in a vertical plane parallel to the wheel, but the material next to this and still covered by the slope sheet tries to assume an angle of repose, which is about 1 in a wide bucket, the material discharges more readily.

Consequently, what might not come out at all in a narrow bucket comes out easily in a Wide bucket. In a wide bucket the relationship of the side friction to the cubic contents is less, and therefore even if packed to the same extent will dump more easily.

Another advantage is that it is not necessary to have cleaning mechanisms such as are needed when a slope sheet is employed. However, simple and inexpensive forms of cleaners maybe employed in connection with the rollers if desired. 1

Yet a further object of this invention is to provide a roller conveyor adapted for use with existing excavating Wheels which embodies a number of the advantages of the present invention and yet which may be applied to present day excavating wheels in place of the usual slope sheet Without modification of the wheel structure itself.

One embodiment provided in accordance with the present invention comprises a digging wheel having a plurality of buckets at its periphery and having an open side and a closel side, with a powered roller conveyor means being provided comprising a series of several cylindrical rollers which extend into the interior of said wheel from said open side to a point where the innermost roller closely adjoins the closed side of the wheel. .The rollers substantially span the distance between the closed side of the wheel and a belt type conveyor or the like, the latter being normally located adjacent to but spaced laterally from the open side, the result being that the rollers receive the earth from. the buckets and convey the earth to the belt type conveyor. Since the rollers are disposed a short distance above the wheel axle, their axial length may be substantial.

As a variation of the foregoing invention, I provide a roller to said. series of rollers at a point above the innermost roller, and closely adjacent the inner surface of the closed side of the wheeL- The additional roller is normally somewhat smaller than the innermost roller, and occupies the V-shaped crevice or space existing between the inner surface of the closed side and the adjacent periphery of the innermost roller. The additional roller prevents any tendency toward a build up of earth in this crevice and adds to the overall efliciency of the invention.

In addition to the foregoing, it is an object of the present invention to provide an excavating wheel which is wider than has been feasible in the past, which is economical of manufacture, and which is highly convenient and efiicient in use.

Other objects. and advantages of the present invention will become apparent in the following description of preferred embodiments of the roller conveyor of the present invention and the usethereof.

Now in order to acquaint those skilled in the art with the excavating wheel of the present invention, I shall, de-

scribe, in connection with the accompanying drawings, preferred embodiments of the excavating wheel and roller conveyors therefor.

In the drawings:

Figure 1 is a diagrammatic view, in elevation, of an excavating apparatus of the bucket wheel type and supporting means therefor;

Figure 2 is a side elevation, on an enlarged scale and with portions broken away, of one form of the bucket wheel and associated apparatus, taken from the side of the apparatus opposite that shown in Figure l and substantially on the line 2-2 of Figure 3;

Figure 3 is a vertical cross-sectional view of thcbucket wheel and associated apparatus, taken substantially on the line 3-3 of Figure 2;

Figure 4 is a cross-sectional view of the rollers and closed side of the excavating Wheel taken substantially on line 4-4 of Figure 2;

Figure 5 is similar to Figure 4 but shows a modification of the invention shown in Figures 1-4;

Figure 6 is a cross-sectional view of the embodiment of Figure 5, but along a line through the main body pertions of the rollers; and

Figure 7 is a vertical cross-sectional view like that of Figure 3, but modified to show the series of rollers downwardly and outwardly inclined from the interior of the bucket wheel.

FIGURES l-4 Referring now to the drawings, wherein like reference numerals indicate like elements throughout the several views, reference numeral 10 in Figure 1 indicates a digging ladder which is pivotally mounted, as at 12, on a fixed support, gantry, or the like, indicated at 14. A digging wheel 16 is rotatably mounted at the free end of the digging ladder 10 and theladder 10 and wheel 16 are supported by a wish-bone or V-shaped element 18 which is under the control of a hoist line 29 rceved over a saddle block 22 provided at the end of a beam 24. The beam 24 is pivotally mounted as at 26 on the fixed support 14. Beam 24 and digging ladder 10 are movable about their pivoted connections with the fixed support 14 by conventional means (not shown). The digging ladder 10 also supports a conveyor belt 28, which extends longitudinally of the ladder 10 from the digging wheel 16 to the fixed support 14. The conveyor 28 may lead directly to a point of disposal or may lead to other conveyors or the like that ultimately lead to a point of disposal.

Figures 2, 3 and 4 illustrate more particularly a preferred embodiment of my improved excavating wheel and manner in which it is associated with the digging ladder 10. The digging wheel 16 comprises a cylindrical shell 30 having secured to the periphery thereof a plurality of toothed buckets 32. A vertical end plate, or side wall, 34 is secured in any suitable manner to the cylindrical shell 30 and is secured to a hub 36 which is rotatably supported, by means of bearings 37, on an axle or shaft 38. The axle or shaft 38 is elongated and is supported adjacent its outer ends by the wish-bone or V-shaped structure 18 through clamps 40, secured to structure 18, which engage the shaft 38. The digging ladder 10 comprises a trussed section including a plurality of horizontal I beams 42, 44 and 46 and. it supports the digging wheel 16 by means of a plurality of bearings 48, 50 and 52, which engage the shaft or axle 38 and are secured, respectively, to the beams 42, 44 and 46. The digging wheel 16 is preferably provided with a rcin forcing plate 54 secured to the vertical end plate 34, and the plate 54 may be provided at its periphery with gear teeth (not shown) for engagement with a suitable driving means whereby the diggingwheel may be driven.

The driving means may be supported on the digging ladder adjacent the digging wheel, or the digging wheel may be driven in any suitable manner.

The digging wheel 16 shown in Figures 14 comprises the separable parts or elements 30, 32, 34, 36, 38 and 54, which may be suitably secured together, as by welding, to provide a sturdy but economically manufactured digging wheel that is closed at one side and open at its other side. The digging wheel illustrated is adapted to cut upwardly, and as the individual buckets move upwardly from the position in which they perform the excavating function, the earth gravitates toward the in-.

terior of the wheel. It is therefore necessary to provide some conveying means to move the earth falling from the buckets to the conveyor belt 28 so that the earth may be removed to a distant disposal point. It has been proposed in the past to provide a slope sheet, fixed to the ladder in a suitable manner, which is disposed in the interior of the wheel at a relatively large angle with respect to the horizontal plane of the wheel. The earth gravitating from the buckets would then contact the slope sheet and slide or roll down said sheet to the conveyor belt, if same is located under the lower edge of the sheet, or slide or roll down to some position on the slope sheet where a mechanism of a suitable type or a laborer would transfer the earth to the conveyor. It has been found, however, that the earth tends to accumulate on the upper surface of a slope sheet, necessitating continual cleaning and maintenance thereof to keep the wheel operating at a feasible efliciency.

I propose to eliminate the slope sheet, and provide a series of powered cylindrical rollers to receive the falling earth and'convey same to the belt conveyor 28. As shown in the embodiment illustrated in Figures 2, 3 and 4, three cylindrical rollers 56, 58 and 60, which preferably are hollow, are disposed in side-by-side relationship, and extend through the open side of the wheel into the interior thereof. The innermost roller 56 is preferably spaced only a slight distance from the closed side wall comprising the vertical end plate 34, and the outermost roller is preferably disposed with a portion thereof above the adjacent edge of conveyor belt 28, as shown in Figure 3. As shown, the series of rollers is preferably disposed in a horizontal plane. However, the rollers may be inclined at a slight angle from inside the wheel down toward the belt, as shown in Fig. 7.

To prevent earth from falling between them, the rollers are positioned closely together. -If they are inclined, they may be positioned so that they overlap slightly with respect to the horizontal axis of the wheel 16, as shown in Fig. 7. Of .course, the amount of material which may fall between the rollers is slight and it drops into the buckets on the lower run of the wheel and is carried up again.

The rollers may be supported on the ladder in any suitable manner. I have illustrated a supporting means (see Figure 4) wherein supporting beams 61 and 62 (located at each end of the rollers) are suitably fixed to beam 44- and to bar 64, respectively, which bar fixedly carries suitable bearings 66, 68 and 70 in which the rollers 56, 58 and 69 are journalled at their ends. The rollers are adapted to be rotated in the direction indicated by the arrows in Figure 3 by any suitable means, such as is illustrated, wherein a drive shaft 72 (see Figure 2) is suitably supported in bearing 74 and engages the shaft '76 of roller 60 by means of a clutch 78. The rollers 56 and 58 may be driven or rotated independently, or may be rotated by drive shaft 72 by means of a chain and sprocket arrangement indicated generally at wherein endless chain 79 cooperates with sprockets 81, 83 and 85 to rotate the rollers 56 and 58 at the same speed as roller 60 is rotated. Other combinations of rotating speed and/or operating mechanisms may be employed to suit particular operating conditions. Manifestly, the drive shaft 72 may be driven from a suitable source mounted on the digging ladder, or from other suitable driving means. I

If desired, a scraper or stop sheet 86 is provided to prevent accumulation of earth materials on the outermost roller. It has been found that since the rollers are spaced quite close to each other, earth cannot accumulate on any of them to any great degree. However, since any earth accumulating on roller 60 would ordinarily not be removed by roller 58 until the accumulation was returned to the interior of the wheel (by rotation of roller 60) and would therefore ordinarily drop down below the rollers, it is desirable to provide the scraper 86 so that such accumulations will drop on the conveyor belt 28 when removed, decreasing the amount of maintenance required. The scraper or stop sheet 86 shown in Figures 2 and 3 is secured to a bracket and extends at an inclination between the upper run of the conveyor belt 28 and the periphery of the outermost roller 60. The scraper or stop sheet 86 is preferably positioned so as to be spaced slightly from the periphery of the roller 60 to scrape any accumulated material therefrom and transfer same onto the belt 28.

To prevent excavated earth from falling from the buckets as the individual buckets move upwardly from the position in which they perform an excavating operation, a plug 90 (see Figure 2), preferably formed of sheet metal, is suitably secured to the digging ladder 10 and extends into the interior of the digging wheel 16 through the open side thereof. The plug 90 is provided with an arcuate wall portion 92 adapted to fit closely adjacent the bottoms of the buckets to prevent displacement of earth materials from the buckets as the individual buckets are moved from a position slightly beyond bottom center to a position slightly above the horizontal axis of the digging ladder 10. The plug 90 is provided at its upper edge with an inclined sheet or plate 91, for guiding material from the buckets 32 onto the series of rollers. The plate extends across the rollers and holes or curvilinear notches are provided therein for the passage of each roller. Forwardly of wheel shaft 38 and parallel therewith, a shaft 94 carrying a pulley or roller 96 is rotatably supported in suitable bearings (not shown) secured to the beams 44 and 46. The pulley 96 comprises the end pulley for the conveyor belt 28 and is so disposed that the upper or earth carrying run of the belt 28 passes above the shaft 38 and adjacent the lower margin of the outermost roller 60. If desired, a suitable shield similar to plate 91 may be fixed to ladder 10 to protect the bearings 66, 68 and 70 and the chain and sprocket arrangement, indicated at 80, from earth accumulations.

Operation In operation, the digging wheel 16 is rotated by a suitable power drive means in the direction indicated by the arrow in Figure 1, whereby an upward out against the surface or a bank of earth or the like to be removed is effected. The toothed buckets 32 of the digging wheel 16 scoop up a quantity of the material of the bank, as determined by the size of the buckets, and carry the material upwardly. The earth is retained in the buckets during upward travel by the plug 90, but as soon as the individual buckets clear the plug 90, the earth material gravitates downwardly onto the inclined plate 91 of the plug 90 and onto the series of rollers, whereupon it is conveyed by the rollers onto the top run of the conveyor belt 28. Should any earth material tend to accumulate on the surfaces of the rollers, it would normally be removed by the close proximity of the adjacent roller or rollers. The scraper or stop sheet 86 effectively cleans such material off the surface of roller 68 before the material can be carried back to the interior of the wheel and allows the material to drop to the top run of the conveyor belt located just below it (see Figure 3). The conveyor belt 28 is driven in any customary manner and carries the material, which has now been transferred to the upper run thereof, rearwardly toward the pivotal support of the digging ladder 10 for disposal thereof.

FIGURES 5-6 In Figures 5 and 6, I illustrate a modification of the excavating wheel described in connection with Figures 1-4, wherein a small fourth roller 100 is utilized to fill in the substantially V-shaped crevice bounded by the in nermost roller 56 and plate 34. Roller 100 may be secured to the bar 64 in any suitable manner, such as by the angle member 102 provided with bearing device 104, in which the roller 100 is journalled. Rotary motion, in the direction of the arrow shown in Figure 6, may be imparted to roller 100 by any suitable means, such as a sprocket fixed to the roller shaft and a chain cooperat ing with a suitable sprocket on the shaft of roller 56. Thus,,when the larger rollers are set in motion by means of the hereinbefore described structure, the small roller 100 will turn in the same direction, and will tend to feed earth material, which might ordinarily collect in the V-shaped crevice between plate 34 and the upper periphery of roller 56, toward the larger rollers, therefore adding to the efficiency of the roller conveyor apparatus. The rollers 56, 58m 60 may be disposed with their, axles in a horizontal plane or in a plane inclined downwardly toward the horizontal.

The aforedescribed embodiments not only provide a more etiicient manner of feeding the excavated earth to the belt conveyor 28, but also increase the capacity of wheel type excavators as well. Since the rather long slope sheet, which formerly projected upwardly quite far into the upper interior of the wheel (and therefore limited the space into which excavated material might be discharged and also limited the possible depth of the buckets 34) is eliminated, the bucket depth and therefore the capacity of each bucket may be increased substantially. Moreover, the width of excavating wheel may be increased materially, and would not be limited by the means for removing excavated earth from the wheel since the roller conveyor hereinbefore described may be made as long as is necessary to convey earth from the interior of the wheel to means such as belt conveyor 28. Also, the buckets can be emptied sooner since the series of rollers does not rise as high as the slope sheet of prior practices. All of these factors, considered together with the increased efiiciency of the roller conveyor apparatus, greatly increase the excavating capacity of the excavating wheel.

The foregoing description and the drawings are given merely to explain and illustrate my invention, and the invention is not to be limited thereto, except insofar as the appended claims are so limited, since those skilled in the art who have my disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

I claim:

1. In anexcavating apparatus, the combination comprising a digging wheel having an axle and having a plurality of excavating buckets at its periphery which buckets are adapted to discharge downwardly from their upper positions into the interior of the digging wheel, a conveyor positioned outside of said wheel, a series of rollers extending into the interior of the wheel for receiving downwardly discharging excavated material from the buckets and for conveying it outwardly of the wheel to said conveyor, said rollers being disposed a short distance above the axle of the wheel and extending across the interior of the wheel to receive discharged material from each bucket through a wide arc of its rotational path.

2. The combination of claim 1, wherein the rollers are inclined downwardly in the direction of the exterior of said wheel and are spaced relatively close together and in slightly overlapping relationship.

3. The combination of claim 1 wherein the rollers are disposed in a generally horizontal plane and said wheel has a substantially vertical inner wall and the innermost roller of the series is disposed closely adjacent said wall in parallel relationship.

4. The excavating apparatus set forth in claim 3 wherein another and smaller roller is disposed adjacent said wall and above the generally V-shaped space existing between said Wall and the innermost roller of said series of rollers.

References Cited in the file of this patent UNITED STATES PATENTS 308,741 Booth Dec. 2, 1884 369,948 Kersey Sept. 13, 1887 655,955 Brophy Aug. 14, 1900 918,373 Rolph Apr. 13, 1909 1,319,058 Fitzpatrick Oct. 21, 1919 1,476,375 Shook Dec. 4, 1923 1,581,318 Liurn Apr. 20. 1926 2,217,075 OMalley Oct. 8, 1940 2,417,846 Stevens Mar. 25, 1947 2,631,718 Rinehart Mar. 17, 1953 FOREIGN PATENTS 67,565 Austria Jan. 25, 1915

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