US2171098A - Earth working apparatus - Google Patents

Description

Aug. 29, 1939. c. A. RAGLAND. SR. El AL 2,171,098

EARTH WORKING APPARATUS Filed July 22, 1938 2 sheets-sneak 1 \O awe/whom Cms-s TEE Aer/{me P464 AND, 52.; cut-s75? ,4? 7/10,? Baez/mo, Jr. #4 65020: 6/; an fnazn/vo.

Aug. 29,1939.

C. A. RAGLAND, SR..

EARTH WORKING APPARATUS F'i1ed.July 22, 1938 2 Sheets-Sheet 2 65026: 6/1 /01 IPAGLAND. 33343 Patented Aug. 29, 1939- 2.171,098- EARTH WORKING APPARATUS Chester Arthur Ragland, Sn, Chester Arthur Bagland, Jr., and- George Gilliam Ragland, Louisburg, N. 0.; said Chester Arthur Ragland, .Sr., assignor to said Chester Arthur England,

I12. and said George Gilliam r;

land

Application July 22, 1938, Serial No. 220,754

which convert the conventional tractor into a power-driven tamping roller. In particular this invention relates to an improved power-driven tamping roller which will be 'eifective to completely tamp and roll earth'surfaces and at the same time beavailable for the ordinary uses of a tractor. 4

It is, therefore, an object of this invention to provide traction increasing elements which are designed to compact road beds, dams, fills, levees I and,the like. Such atraction element is referred to broadly as a sheep foot tamper.

Thepurpose of the sheep's foot tamping roller is to obtain uniform compaction of layers of loose material. Voids are destroyed and efllcient tamping is accomplished on level or uneven ground. The plane surfaced roller of the prior art produces a smooth surface but not necessarily a hard one. Uneven compaction results with voids and soft spots in each layer. This is particularly true when the material is lacking in cohesiveness. Weighted drum tamping rollers designed to be pulled by a tractor or other means have been I used by the prior art but they are of costly construction and are one-service units. In the prior art tamping roller it has been necessary to have a number of complete rollers with a varying number of tamping feet. However, by the use of our invention, the specifications of the engineers can be met with the one piece of equipment. Further, with our invention, the tractor is converted into a power-driven tamping roller and is available for any needed power service such as bulldozing, 5 trail building, terracing, hauling, stump pulling or any other purpose for which a tractor with conventional tread is normally used.

The tamping feet are so shaped as to provide a surface-bearing area that gives e'xcellent'compacting results. In one embodiment of our invention they taper slightly toward their outer ends and their outer faces are sufficiently broad to perform a tamping as distinguished from a digging or plowing action. A further advantage 5 of our tamping foot is its ready attachment to conventional tractor wheels. It may be applied easily and quickly either to supplement or replace the conventional tractor tread and when applied is securely held in position.

50 Referring to the drawings, it will be seen that our invention contemplates a power-driven tamping roller comprising a tractor having wheels upon which are mounted a plurality of tamping units. 7 55 Figure -1 is a side view of atractor equipped with our improved tamping lug in place of the conventional traction-increasing elements.

Figure 2 is a front view of a tractor equipped with our sheep foot tamping lugs showing one arrangement of the tamping feet on the tractor 5 wheels.

Figure 3 is a detailed view of a, portion of the periphery and lug attached thereto.

Figures 3 and'4, 5 and 6, and 'l and 8 represent views of three specific tamping units. 10

The tread surface of each tractor wheel is provided with a plurality of sheep foot lugs which, as seen in Figures 1 and 2, are arranged circumferentially in rows, the lugs of one row being staggered with respect to the lugs of the ad- 15' iacent row. l

The lugs may be bolted, riveted, welded or otherwise. fastened to the tractor wheel. However, in the conversion of existing tractors, it is preferred to bolt or rivet the tamping unitto 20, the wheel. When the tamping units are'applied in this manner they are readily removed when it becomes necessary to replace damaged tampers.

As shown in detail in Figures 3, 5, and 7, each of the tamping feet is provided with flanges a 25 having holes 3 for attachment by bolts or rivets to the periphery of the tractor wheel. The outer periphery of the tractor wheel is shown at 5 in Figures 1, 2 and 3 and we have secured to this periphery a plurality of sheep foot tampers. Since bolts or rivets 6 pass through the flanges 2 of the tamping lugs and the periphery 5 of the tractor wheel, it will be seen that'the lugs are securely held to the tractor wheel.

Referring particularly to Figures 1 and 2, the modified front wheel assembly comprises the usual swivel yoke I and transverse shaft 3 carrying wheels 9 with broad bearing surfaces 5. The front wheels are of suflicient width so that when combined with the rear wheels there is, in effect 40 a continuous tamping roller of an overall width equal to the distance between the outer rims ofthe rear wheels.

,Our sheep foot tamper is substantially selfcleaning and being tapered, easily penetrates the layer. However, a comb-type cleaner may be provided. The tamping feet are spaced apart and therefore tamp in spots. The earth or other material being tamped isin a soft or loose condition and 5 the tamping feet are of a length which corresponds to the depth of the loose layer. Consequently, each tamping foot will penetrate the loose layer and compact a small part of the loose material upon the solid layer beneath, On each 35 desired compaction.

successive passage of the tampingroller an increment of the tamped material is pressed down upon that previously compacted so that repeated passages of the tamping roller gradually build 5 up and compress solid layers of material. With the movement of the tractor forward or backward there is but little tendency of our tamping foot to disturb the compacted layer. Eventually, the entire fill or road bed is packed s'olidly from the 10 bottom upward through the layer and the mate- 15 toward the underlying bed. With such improper tamping thematerial settles. Only with sheep foot tampers can this work be done satisf: ctorily;

Each wheel may carry a plurality of rows of feet with from about one to about four feet per 20 sq. ft. of wheel bearing surface. The feet are from about five inches to about eight inches in length. The bearing surface of each foot is from about four sq. in. to about six sq. in. exerting a pressure of from about 150 pounds to about 250 pounds per 25 sq. in. The number of feet on the ground at any one time, the weight of the tractor, and the area of the tamping surface determine the effective pressure.

The purpose of varying the pressure per square of different engineers. With the same weight on the ground per tamping foot and fewer feet, a large number of trips is required to secure the $ome engineers prefer a greater number of rollings and then fewer tamping feet are used. In the prior art tamping roller it was necessary to have a number of complete rollers with a varying number of tamping feet.

40 By the use of our invention the number of feet may be varied at will to meet the specifications of the engineers.

e The length of the sheep foot should be slightly more than the depth'of the layer to be compacted.

45 The area of the bearing surface is dependent upon the. pressure desired per square inch. By varying the area of the tamping'foot and the number of tamping units on the ground at any one time, the effective pressure is controlled. A pressure of 50 about 200 pounds to about 225 pounds per sq. in.

is a common specification.

In a preferred embodiment of our invention, we provide a lug as shown in Figures 3 and 4. The shank of this lug has substantially rectangular 55 cross section tapering slightly toward ,a. point about one inch below the bearing surface. The} outer end is flared toward the front to form the sheeps foot or bearing surface. Thebearing surface has an-area of approximately five. sq. in. and

the distance from the periphery of the wheel to the center of the bearing surface is about 6% inches. This lug is intended for compacting layers which do not exceed about six inches in depth and is substantially self-cleaning. 6 Referring further to Figures 1 and 2, the powerdriven tamping r ller shown has a gross weight of approximately 7 0 pounds. About 5800 pounds are represented byxthe base weight of the tractor and rims, whilethe tamping units weigh approximately ten pounds each, of which there are 160.

There are five circumferential rows of twelve tamping units on each of the rear wheels. The

1 area of each rim of the driving wheels is approximately 22 sq. ft. With a total of sixty tamping tamping units per sq. ft. of driving wheel surface.

Each circumferential row of tamping units is staggered with respect to the next and this arrangement is carried over to the front wheels and the second rear wheel resulting in a continuous roller having an effective width as shown in Figure 2. There are fourteen circumferential rows bearing surface of the tamping unit, the pressure may be'increased. For example, if the triangular lug shown in Figures 7 and 8 or any of the other lugs had a bearing surface of approximately 3% sq. in., and if the arrangement of the lugs remained the same as shown in Figures 1 and. 2, the effective pressure would be about 300 pounds per sq. in. Obviously, by increasing the bearing surface area of the individual lug or by increasing the number of units, the pressure may be decreased;

In another embodiment of our invention the tamping feet may be steel forgings or castings substantially circular in cross section with a large flaring base provided with means for securely atand this forms a cutting edge which assists in the breaking of any hard crust or surface on the loosened .or uncompacted layer. As in the other embodiments, the bearing surface area of the tamping foot and. the length may be variedto obtain the desired results.

While we have in the above specification described certain specific embodiments of our invention, it will be understood that modifications may 'be'made without departing from our invention as claimed. I

What we claim-is I 1. A self-impelling road rolling and tamping machine comprising a tractor which has a plurality of wheels mounted on a rear axle and a front axle, each wheel having a wide periphery, a

chassis supported on said axles, a source of automotive power mounted on said chassis and adapted to impart a driving force to the wheels mounted on at least one of said axles, all of the said wheels of said tractor being provided with sheepfoot tamping units on the .periphery thereof. 4

2. A self-impelling road rolling and tamping machine comprising a tractor which has a'plurality of wheels mounted on a rear axle and a front axle, each wheel having a wide periphery, a chassis supported on said axles, a source of automotive power mounted on said chassis and adapted to impart a driving force to the wheels mounted on. at least one of said axles, all of the said wheels of said .tractor being provided with demountable sheep-foot tamping units on the periphery thereof.

3. A self-impelling road rolling and tamping machine comprising a tractor which has a pair of driving wheels and a pair of driven wheels mounted on a rear axle'and a front axle, each mounted on at least one of said axles, allot the wheel havinga wide periphery, the chassis supported on said axles, a source of automotive power mounted 'on said chassis and adapted to impart a driving force to the wheels mounted on at least one of said axles, all of the said wheels or said tractor being provided with sheep-foot tamping units on the periphery thereof.

4. A self-impelling road rolling and ta'm'ping machine comprising a tractor which has a pair of driving wheels and a pair of driven wheels mounted on a rear axle and a front axle, each wheel having a wide periphery, a chassis supported on said axles, a source of automotive power mounted on said chassis and adapted to impart adriving force to the wheels mounted on at least one oi. said axles, all of the said wheels of said tractor being provided with demountable sheeptoot tamping units on the periphery thereof.

5. A self-impelling road rolling and tamping machine comprising a tractor which has a plurality of wheels mounted on a rear axle and a front axle, each wheel having a wide periphery,

a chassis supported on said'axles, a source of automotive power mounted on said chassis and adapted to-impart a driving force to the wheels said wheels of said tractor being provided with sheep-foot tamping wnits'on the periphery thereof, means for selectively demounting selected of the sheep-foot tamping units whereby the edective pressure on the material being tamped may be varied at will.

- 6. A self-impelling road rolling and tampin'g machine comprising a tractor which has a plurality of wheels mounted on a rear axle and a. front axle, each wheel having'a wide periphery, a chassis supported on said axles, a source of automotive power mounted on said chassis and adapted to impart a driving force-to the wheels mounted on at least one of said axles, all of the said wheels of said tractor being provided with demouritable sheep-foot tamping units on the periphery thereof, means for selectively demounting selected of the sheep-foot tamping units whereby the effective pressure on the material being tamped may be varied at will.

CHESTER ARTHUR RAGLAND, Sn. CHESTER ARTHUR RAGLAND, .m. .GEORGE GILLIAM RAGLAND.

Images