US2882623A - Combined grading and rolling machines - Google Patents

Description

April 21, 1959 A. w. GARDNER 2,832,623

. COMBINED GRADING AND ROLLING MACHINES I Filed June 25, 1953 4 Sheets-Sheet 1 ATTORNEYS April 21, 1959 A. w. GARDNER COMBINED GRADING AND ROLLING MACHINES 4 Sheets-Sheet 2 Filed June 25, 1953 INVENTOR M KLUMQ ATTORNEYS April 21, 1959 A. w. GARDNER ,8 2

v COMBINED GRADING AND ROLLING MACHINES Filed June 25, 1953 4 Sheets-Sheet 3 v r 35 I I INVENTOR ATTORNEYS April 21, 1959 A. w. GARDNER COMBINED GRADING AND ROLLING MACHINES Filed June 25, 1955 4 sheets-sheet 4 INVENTOR ATTORNEYS United States Patent COMBINED GRADING AND ROLLHIG MACHINES Adryl Wade Gardner, Redlands, Calif.

Application June 25, 1953, Serial No. 363,985

13 Claims. (Cl. 37-146) My invention relates to road building and maintaining machinery, and relates more particularly to road grading machines having rollers for simultaneously rolling the graded surface during each pass of the scraper.

It is an important object of my invention to provide a combination road grader and roller wherein a standard road grading machine may be fitted with rolling means to provide a single machine to perform on each pass first a grading function and then a rolling function immediately thereafter.

In the past, road graders have been provided with rolling equipment in the form of either a towed unit or in the form of a fixed rolling device attached to the grader chassis so that the roller may be lowered into engagement withthe ground or may be elevated thereabove during periods of disuse. In the form of roller which is merely towed behind the road grader the roller has no function except that of compaction. That is to say,-since the towed roller carries none of the weight of the grading machine there is no inter-relation between the weight of the machine which is supported by the roller and that which is supported by the grader drive wheels. In the formof rolling device which, according to the prior art, has been carried on the grader chassis, there is the inherent disadvantage that when the rolling mechanism is lowered into working contact with the ground the roller is held in a fixed relation with respect to the guide and traction wheels of the grader and thus the roller is not free to independently follow transverse and longitudinal variations in the grade surface. I

Therefore, one very imporatnt object of the present invention is to provide in combination with a road grader a rolling evice which compacts the grade material to a substantially uniform degree. To achieve this purpose, it is necessary that the rolling device not be rigidly mounted on the chassis of the grader. In cases in which the rolling device is rigidly attached to the grader chassis uniform compaction of the grade material is not achieved since the roller stresses the high spots of the material heavily but scarcely touches the lower spots. Moreover,

when the rolling device is rigidly attached to the chassis,

an elevation in the grade material which cannot be leveled by the compaction effort of the roller causes the roller to lift the grader chassis at the point of attachment,an d such lifting causes the normal weight distribuion on the wheels of the grader to be altered so that either steering of the grader is impaired or else the grader is hung up on the roller with its drive wheels suspended off the ground. This type of machine, therefore, is not satisfactory since it performs mainly to roll the grade material toa constant level rather than performing to roll the material to a uniform degree of compaction.

' It is therefore a primary object of my invention to provide a combined grader and roller wherein not only are the rolls so mounted that they are free to follow both the transverse and longitudinal variations in the grade surface but so that the rollsand the drive wheels divide the weight of the machine according to a predetermined 2,882,623 Patented Apr. 21, 1959 ratio. In order to accomplish this purpose I have used a type of machine having a drive frame on each side of the machine, which frames are respectively pivotally mounted on the machine intermediate the ends of the frames. Drive is furnished through pivotal mounting points to shafts on the frames located forwardly of the pivot point, which shafts each carry a drive wheel. At

the aft end of each frame is an extension frame which is rigidly secured thereto, each extension having a set of longitudinally aligned trunnions. Journaled in these trunnions are longitudinally disposed beams carrying stub axles transversely disposed therethrough, and a plurality of roller wheels are carried by these stub axles. By this means it will be seen that the weight of the machine, as applied to the point at which the said frames are attached to the sides of the machine, will be distributed to both the forward drive wheels and to the following roller wheels, and it will furthermore be seen that the individual frames on each side of the machine are free to oscillate about said transverse pivot points whereby the respective roller wheels and drive wheels will at all times bear their respective share of the weight of the machine. The oscillating of the frames about the said pivot points, therefore, permits both the drive wheels and the roller wheels to follow the longitudinal contours of the grade material, and the rocking of the stub axle beams about said longitudinally disposed trunnions will permit the roller wheels to follow any transverse variations in the contour of the grade material.

An additional important object of my invention is to provide means whereby the proportion of the weight respectively carried by the drive wheels and the roller wheels may be altered by the operator of the machine from his control station. So long as the operator does not choose to control the distribution of the weight between the respective drive wheels and roller wheels on each side of the machine, the proportion of the weight of the machine which is carried by said drive wheels and by said roller wheels will be predetermined by the length of the respective moment arms from the point of pivotal mounting of the frames to the drive wheels and to the roller wheels. However, when it becomes desirable to shift the weight distribution (for instance, for the purpose of throwing greater weight on the drive wheels so as to provide additional traction between the drive wheels and the grade surface) the weight distribution may be altered by means of a hydraulic cylinder and piston assembly whereby the'angular position of the frames with respect to the chassis of the machine may be predetermined. In order to control this weight distribution I have provided a hydraulic piston and cylinder connected between the chassis of the machine and the respective.

frames on each side of the machine, said piston and cylinder assembly being pressurized by a source of .hydraulic pressure to forcibly alter the angular position of each frame with respect to the chassis of the machine so as to alter the weight distribution on the respective drive wheels and roller wheels about the pivotal mounting of each frame on the chassis of the machine. By this means the weight carried by the traction wheelsof the machine can be increased above the weight which these wheels would normally carry when said cylinders are not pressurized so as to provide additional traction between said wheels and the ground to keep the machine moving along the surface and to avoid slippage of the traction wheels.

Further objects of my invention include the provision of a strong and simple roller structure which will not only allow the scraping portion of the machine to operate I. will now describe with particularity the embodiment off my invention shown in. theaccompanyingjdrawings wherein:

Figure 1 is a side elevationof thegrader roller*com= bination.

Big. 2 .is .a plan viewthereof.

andth'e' traction wheels showingjthe same snpportedfon" apivotally mountedTframeworklwhichris' a pjartof"the standard road grader illustrated.

Fig; 4 is. aview" similar to Fig; 3' but-f howing. the" rolling. me anisnr and tracticin" wheels" riding" different longitudinal'elevations of the grade surface. H

Fig: S isarearviw ofihe gradr rollershown in Figs: 1i and 2; in which the rollingnieansis shownfollowing'; thesurfaceofanon-level grade. k

Fig; dis a viewsimilarto Fi Sbilt showing 'therolting means riding'on a level surface.-

Fig. 7 is a schematic diagramof the? hydraulic circuit; showing the elements and arrangement thereof" selective= lyfdis'tributingtheweight of. the aftendofthe machine" between the rollers'and the traction wheels;

Fig. 8"is a sectional view-showing one ofthe control valvesofFig. 71in closed position; i

Fig; 9 'is a sectional .viewshowinganotherf of" the con v trol valvesof Fig. 7 in open position";

Fig: 10 1's a perspective view of one of the roller wheel axles showing the supporting beanr and" trunnion for providing transverse freedom of motion;

Referring to the'drawings, the grader-roller includes m'o'stof the elements'of a standard roadgrader, consistingprinoipallyof a main chassis which may be ofany include an engine and'engine housing. 10, anda pair of tandemdrive frames 20: Tandem drive frameslfl are apart'of the standard form ofroad grader shown and" are'provided with traction wheel-drive shafts 21 journalediin carriers 22 and. 23. Figures l, 2, 3 and? 4 show" forward traction wheels Z4Lmounted on .those trac tion wheel drive shafts 21 which. are earried'lhy drive shaft"c'arriers22. In a standard road;v grader additional! traction wheels; identicalto traction wheelsfl t; would normally be mounted on andd riven by the' aft drive shafts 21; journaled'in the aft drive shaft carriers 23. Theseadditional tractionwheels are not shown in the dr'awingssince theyare notemployed acco'rdingrto this invention;

In the standard form of road grader shown. in. the drawings, the chassis '1 issupported at the rear! on .journails 25. on which eachtandem drive frame 20'is pivotally" mounted; Concentricwith andjournal'ed 'in journals 25' arethetransmission driveshafts 26wh'ich'are connected? through chain drives 26a to transmit power: from the engine and'main transmissionto the drivelshaft's v2'1.

The descriptionof the machine so far has included only theessential elements of? a standard road grader. with the rear: traction wheels" ofthe. tandem drive re moved:

The rolling means; according; to my invention,.- con1- tending portionsof the tandem drive housings 20. The embodiment of'the rolling means shown in the drawings includes two separate roller extension frames 27 rigidly attached to tandem drive frames 20. The extension frames 27 are each fitted with a pair of aligned trunnion hearings 27a in which are journaled trunnion beams 28, a perspective view of which is shown in Fig. 10. Aligned trunnion pins 29 are journaled intrunnion bearings 27a to; permit freeoscillation of trunnion beams. 28; Projecting laterally from the trunnion beams 28 are roller wheel axles 30 on which are journalcd' a plurality of roller wheels.-31. Oscillationof: thetrunnion. beams 28 transversely of the grader-roller permits the roller wheels 31 to follow the ground contours as illustrated in Figs. 5 and 6.

Fixed to and extending downwardly from the outer side of each extension frame 27 is a member 32 which is provided with a vertical slot33 which guides the extremity-30a ofithe roller wheel axle lill-when the trunnion beam.

28. oscillates in trunnion bearings 27a, this structure permittingroller wheels 31-to follow transverse variations in theground contourbut limiting-theangle through which the trunnion beams 28 may pivot.

Itisto be understood-that the rollerwheels 31 carried.

by; the roller extension frames.27 support the rearwardly extending.- portions oftandem. drive frames 20 andre- I place the traction wheels which would be mountedron aftshafts 21.(journaled in drive shaft carriers 23) on the. standard grader. In this manner tandem .drive frames 20are supported at'both ends, at the forward ends by traction wheels 24 and at the-aft ends by roller wheels 31.-

As -hereinbefore describedit will bereadily understood that the roller-whee1s=31 may follow both'the longitudinal and the transverse variations in the grade surface.

An important provisionof myinvention is ahydraulic-apparatus' for controllingthe pivotal position of the-tandem-drive frames 20 about supporting journals-25. This feature is in additionto the structure as-hercinbefore described,-. and comprises a fiuidpressure systernincludiuga pair of hydraulic cylinders 34 pivotally mounted as at 40 at their upperends to brackets 39'on the chassis 1. The cylinders 34 are equipped with reciprocable pistons 35: having piston rods 36 pivotally connected at 37 to brackets38 fixed to tandem drive frames 20, Figs. 3 and 4. Further elements of thehydraulic circuit as shownin Figs. 7, 8 and 9 include a sump 41 for oil or other similar liquid, the liquidflowing by suction through a pipe. 50

to a gear pump 42. 51 denotestheoutlet pipe leading from said pump, said pipe communicating through a T 69 and apipe 70-with azvalve casing 43 and=with arby pass-casing. 47. Valve-casing 43 communicates-with a T- 54zthroughpipe 52 and: thenthrough a pipe61-to. another. T 57,.thence-throughrpipes 44 intozthe upper ends: of the. cylinders. 34.

cates" with F 67 through pipe 71;. .pressure relief bypass: valve, and pipeflZ;

Withthe-"parts of the-hydraulic; circuit arranged. as described, the manner in which :the hydraulicacontrolsrop?- erate can-be readilywunderstood; With. the hydraulic circuit filled with oil-or other. operating. fluid,.and' with thevalves set as shown in Fig. 7, operatingrfluid is. supplied undenpressureagainst the upper: sideof: pistons 35 in. cylinders 34,-. causing. pistons 35- and rods .36" to travel: downwardly. Fluid thus :displacedfromthedower-endd:

assaeas oficylinders34 by pistons 35 is discharged through pipes 46, 62, 53, valve 43, pipes 66, 68 and 65 to sump 41. When valve 43 is rotated by control lever 43a 90 counter-clockwise from the position shown in Fig. 7, fluid under pressure is supplied against the lower sides of pistons 35 in cylinders 34, causing pistons 35 and rods 36 to travel upwardly. Fluid thus displaced from the upper ends of cylinders 34 by pistons 35 is discharged through pipes 44, 61, 52, valve 43, pipes 66, 68 and 65 to sump 41. When valve 43 is rotated to closed position as shown in Fig. 8, pistons 35 and rods 36 are held against movement in either direction. Under such a condition, fluid delivered under pressure from the pump flows through pipes 51 and 71 through pressure relief by.-pass valve 47 and is returned through lines 72, 68 and 65 to sump 41. It can thus be seen that pistons 35 and rods 36 can be forced to move in either direction and can also be held against movement, by selectively setting valve 43. Also it will be seen that forced movement of pistons 35 and rods 36 causes the tandem drive frames 20, at the respective opposite ends of which are mounted roller wheels 31 and traction wheels 24, to pivot around journals 25 to the position desired. In this manner, normal distribution of the weight between traction wheels 24 and roller wheels 31 can be altered and the ground pressure can be increased above the normal pressure on the traction wheels to provide additional traction when required. Such a requirement may be occasionally encountered in materials not-providing good traction characteristics or when additional blade 2 cutting thrust is required. It is to be understood that in normal operation of the graderroller, tandem drive frames 20 are permitted to pivot freely around journals 25 so that the load distribution between traction wheels 24 and roller wheels 31 is a natural function of the cantilever action of the tandem drive frames 20, and remains a constant.

Provision for the free pivoting of tandem drive frames 20 around journals 25 is provided in the hydraulic circuit by valve 45. With valve 43 in closed position as shown in Fig. 8, and with valve 45 in closed position as shown in Fig. 7, pistons 35 and piston rods 36 are held against movement in either direction, as hereinbefore described, and the tandem drive frames 20 are thus held against rotation about journals 25. However, when free rotation or pivoting of tandem drive frames 20 around journals 25 is desired, for normal operation of the grader-roller, valve 45fiis rotated by control lever 45a to open position as shown in Fig. 9. With valve 45 in open position, pistons 35 and piston rods 36 are free to float in either direction in cylinders 34 so that the tandem drive. frames 20 are then free to pivot around journals 25. When pivoting of the tandem drive frames 20 is in a direction causing downward travel of pistons 35, hydraulic fluid displaced from the lower ends of cylinders 34 flows through pipes 46, T 56, pipe 62, T 55, valve 45, pipe 59, T 54, pipe 61, T 57 and pipes 44 to the upper ends of cylin: ders 34. Since downward travel of pistons 35 and rods 36 does not displace a volume of hydraulic fluid as great as the volume of cylinders 34 above pistons 35, additional hydraulic fluid is drawn by suction from the overflow tank 49 through pipe 60, valve 45, pipe 59, T 54, pipe 61, T 57 and pipes 44. When pivoting of the tandem drive frames 20 around journals 25 is in a direction causing upward travel of pistons 35, more hydraulic fluid is displaced than the increased volume of the portions of the cylinders below the pistons 35 can accommodate. Consequently, the excess hydraulic fluid flows through the same circuit afore described, in reverse direction, to overflow tank 49. In this manner, pistons 35 and rods 36 are free to travel in either direction in cylinders 34 and the tandem drive frames 20 are thus free to pivot in either direction around journals 25, thereby permitting the roller wheels 31 and traction wheels 24 to follow the ground contours without disturbing the normal weight carried by either.

1. A combined road material scraper and roller comprising a chassis; ground engaging steerable wheels at onevend of said chassis; two independent frames, each pivotally connected intermediate its longitudinal ends on the other end of said chassis on opposite sides there of, the respective pivots lying along a transverse axis; a ground engaging drive wheel carried by each frame:

at one end thereof; a motor connected to'drive said drive wheels; transverse axle means carried by each frame at the end thereof opposite the drive wheel, said axle means occupying a common transverse vertical plane and extending toward each other substantially to the transverse center of the chassis; a plurality of ground engaging rollers freely journaled on each axle means, the weight of the machine as applied to said frames at said transverse axis normally being distributed between said rollers and said drive wheels; road material scraper means carried on said chassis between said frame means and said steerable wheels; and power actuated means connected between each frame and said chassis for applying a tilting pressure to said frames about said transverse axis to alter the normal weight distribution between said roll-- ers and said drive wheels.

2. In a device as set forth in claim 1, the roller carry-' ing end of each frame having opposed longitudinally aligned trunnion bearings, a beam journaled in said bearings, said axle means comprising an axle fixed through the center of each beam, said rollers being symmetrically journaled on each axle with respect to said trunnion bearings; and meansto limit the angle through which said axle may tilt from horizontal.

3. In a device as set forth in claim 1, said power actuated means comprising a piston and cylinder connected between one end of each frame and said chassis; a source of fluid pressure; valve means to selectively apply fluid pressure to either end of said cylinders to cause the pistons to be moved therein; and valve means to connect together the respective ends of said cylinders to permit free motion of the pistons therein, the pistons being locked in the cylinders when both valves are closed.

4. A combined road material scraper and roller com prising a chassis; ground engaging steerable wheels at one end of said chassis; frame means pivotally connected intermediate its longitudinal ends to the other end of said chassis along a transverse axis; transversely spaced ground engaging drive wheels carried by said frame means at one end thereof; a motor connected to drive said drive wheels; a plurality of ground engaging rollers freely journaled on said frame means at the end thereof opposite said drive wheels, the Weight of the machine as applied to said frame means at said transverse axis normally being distributed between said rollers and said drive wheels; road material scraper means carried on said chassis between said frame means and said steerable wheels, the roller carrying end of the frame means having pairs of opposed longitudinally aligned trunnion bearings; and a beam journaled in each pair of bearings, said beams each having fixed through its center a transversely disposed axle, said rollers being symmetrically journaled on said axles with respect to the associated beam.

5. In a device as set forth in claim 4, power actuated means connected between said frame means and said chassis comprising a piston and cylinder connected between one end of said frame means and said chassis; a source of fluid pressure; valve means to selectively apply 7 fluid pressure to :either end -:'of said cylinder to cause the piston to he .moved therein; and valve means to connect together :the respective ends of said cylinder to permit free motion of the piston therein.

=6. ,A combined road material scraper and roller comprising a chassis; ground engaging steerable wheels at onerendzof'said chassis; two independent frames, eachpivotally connected intermediate its longitudinal ends to the other end of said chassis on oppositesides :thereof, the respective pivots lying along a transverse axis; a groundengaging drive wheel carried by each frame at one end thereof; a motorconnected to drive said drive wheels; a plurality of ground engaging rollers freely journaled on each frame at the end thereof opposite the drive wheel, the weighttof the machine as applied to said frames at said transverse axis normally being distributed between said rollers and said drive wheels; road material scraper means carried on said chassis between "said frames and said steerable wheels, the roller carrying end of each frame shaving :opposed longitudinally aligned trunnion bearings; and a beam journaled in said bearings, said beam having fixed through its center a transversely disposed axle, said rollers being symmetrically journaled on said axis with respect to said trunnion bearings.

.7. In a device as set forth in claim 6, means on each frameengaging each axle to limit-the angle through which said zaxle may tilt from horizontal.

8. In combination with a scraper-type road material grading machine having a chassis carrying a scraper and having steerable wheels at one end, and having at the oflier and two longitudinally disposed frames, one on each side of the chassis and each .frame being independently pivotally mounted to the chassis along a transverse axis intermediate its longitudinal ends and each frame carrying a motor-driven drive wheel at one end; roller supporting means fixed to each frame at the end opposite the drive wheel and including axle means occupying a common transverse vertical plane and said axle means extending toward each other substantially to the transverse center of-the chassis; rollers freely journaled on said axle means, the combined width of the respective rollers contacting the road material across 'at least the full width of the machine; and power actuated means respectively connected between each frame and said chassis whereby the frames may be tilted to alter the normal distribution of the proportion of the weight of the machine carried by said drive wheels and by said rollers.

9. .In a device as set forth in claim 8, the roller carrying :end of each frame having opposed longitudinally alignedtrunnion bearings, a beam journaled in said bearings, said axle means comprising an axle fixed through the ceriternteafibeam, "said ro'lle'rs being symmetrically journaledon each axle with respect tosa'id trunnion bearings, and means to limit the angle through which-said axle may tilt from horizontal.

10. In a device'as set forth in-claims 8, said power actuated means comprising a piston and cylinder connected between one :end ef-each frame and said chassis; a source of :fiuid pressure; valve'me'a'ns to selectively apply fluid pressure to either end of said cylinders to cause the pistons to be moved therein; and valve means to connect together the respective ends of said cylinders to permit free motion of the pistons therein, the pistons being locked in the cylinders when both valves areclosed.

1'1. Incombination with a road material gradingmm chine having a chassis i and having steerable wheels :at one end, and having at the other end two longitudinally disposed frames Ion opposite sides of the chassis, each frame being independent and pivotally mounted to the chassis along a transverse axis intermediate its longitudinal ends and .each frame carrying .a motor-drivendrive wheel at one "end; two independent roller supporting means eachifixed to a frame at the end opposite the drive wheel :and each including .axle means occupying a-com mon transverse vertical plane; and rollers freely journaled on :said :axle means.

12. In a device as set forth in claim 11, power actuated means respectively connected between each frame and said chassis whereby :the frames may be tilted to alter the normal distribution of the proportion of the weight of the machine carried'by said drive wheels and by-said rollers.

13. In a deviceas set forthzin claim 11, the roller carrying .end of each .frame having opposed longitudinally aligned trunnion bearings, a beam journaled in said bearings, said axle means comprising an axle fixed through the center of each beam,.said rollers being symmetrically journaled on each axle with respect to said trunnion bearings; andmeans to limit the angle through which said axle may tilt from horizontal.

References Cited inthe file of this patent UNITED STATES PATENTS 1,794,696 Le Tourneau Mar. 3, 1931 1,981,821 Beatty et al. Nov. 20, 1934 2,050,282 Dillard Aug. 11, 1936 2,132;059 Trembly Oct. 4, 1938 2,610,557 Bros et al. Sept. '16, 1952 FOREIGN PATENTS 121,530 Great Britain Dec. 24, 1918

Images