US3256787A

US3256787A - Road base building apparatus

Info

Publication number: US3256787A
Application number: US281919A
Authority: US
Inventors: William H Lewis
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-05-21
Filing date: 1963-05-21
Publication date: 1966-06-21
Anticipated expiration: 1983-06-21

Description

June 21, 1966 w. H. LEWIS 3,

ROAD BASE BUILDING APPARATUS Filed May 21, 1963 5 Sheets-Sheet l INVENTOR. WILLIAM H. LEWIS BY FULWIDER, PATTON,

RIEBER, LEE & UTECHT ATTORNEYS ROAD BASE BUILDING APPARATUS Filed May 21, 1963 5 Sheets-Sheet 2 FIGZ INVENTOR. WILLIAM H. LEWIS BY FULWIDER, FATTON,

RIEBER, LEE & UTECHT ATTORNEYS June 21, 1966 w. H. LEWIS ROAD BASE BUILDING APPARATUS 5 Sheets-Sheet 3 Filed May 21, 1963 INVENTOR.

H. LEWIS PATTON WILLIAM BY FULWIDER RIEBER, LEE a. UTECI iT AT TOR NEYS June 21, 1966 w. H. LEWIS 3,256,787

ROAD BASE BUILDING APPARATUS Filed May 21, 1963 5 Sheets-Sheet 4 2 FIG.6 a 225 234 1 0 new zaa 224 222 @242 FIGQ INVENTOR WILLIAM H. LEWIS BY FULWIDER, PATTON,

RIEBER, LEE & UTECH'I' ATTORNEYS June 21, 1966 w. H. LEWIS 3,256,787

ROAD BASE BUILDING APPARATUS Filed May 21, 1963 5 Sheets-Sheet 5 FIG. IO

FIG. I I

a INVENTQR. V WILLIAM H. LEWIS BY FULWIDER. PATTON.

RIEBER, LEE & UTECHT ATTORNEYS United States Patent 3,256,787 ROAD BASE BUILDING APPARATUS William H. Lewis, 9530 E. Rush St., Arcadia, Calif. Filed May 21, 1963, Ser. No. 281,919

' Claims. (Cl. 94-44) The present invention relates to road building apparatus, and more particularly to an improved road base building apparatus.

Major economies have been effected in the construction of modern highways by reason of the utilization of large, semi-automatic concrete finishing machines. As is Well known, these machines are adapted to spread, compact, and finish in one operation a slab of concrete as much as 9 inches thick and 24 feet wide.

However, the road subbase or base has not heretofore been prepared to the exacting specifications to which the finished slab is made, and considerable time and expense have been required to grind the finished highway or road surface to eliminate irregularities caused by unevenness in the subbase or base.

Accordingly, it is an object of the present invention to provide a road base building apparatus which is adapted to perform a variety of different but related functions, including the preparation of the .subgrade for a road, the spreading and leveling of a rock base for a road, and the spreading and leveling of cement-treated material for a road, providing in all cases a road bed or road base which is uniform, accurate and smooth.

Another object of the invention is to provide a road base building apparatus of the aforementioned character which is adapted to accomplish the above-described functions quickly and inexpensively through the utilization of semiautomatic components under the control of one operator.

A further object of the invention is to provide a road base building apparatus of the aforementioned character which is self-propelled and adpated to follow a pair of conventional windrowers which are supplied by usual dump trucks, and adapted to split, spread, and level windrows laid by the windrowers. An ancillary feature of the present apparatus is the utilization of moving shovels, rakes, and screeds to work the material to a uniform consistency, with minimum segregation.

A further object of the invention is to provide a road base building apparatus adapted to lay a cement-treated base on a road b ed smoothly, with minimum segregation, and to a very accurate grade. 4

Another object of the invention is to provide a road base building apparatus of the aforementioned character which has a comparatively great width, 27 feet in one embodiment, and a comparatively long wheel base, 34 /2 feet in such embodiment, whereby there is eliminated the elfect of grade deviations that might otherwise be 'transferred to the finished surface of the pavement.

A further object of the invention is to provide a road base building apparatus which is adapted to spread and level a variety of base course materials, and which can also be utilized as a heavy-duty, highly accurate subgrader as well.

An additional object of the invention is the provision of a road base building apparatus which incorporates heavy steel members which are securely braced to provide a rugged, rigid frame to minimize inaccuracies due ice to deflection. In this regard, it is a salient feature of the invention that the hydraulic controls for the various components are elevated and centrally located within easy reach of the operator so that the performance of the apparatus can be continuously monitored and controlled by the operator.

A further object of the invention is to provide an apparatus of the aforementioned character in which the rakes, shovels, and screeds are characterized by a reciprocating action which extends the full width of the apparatus, while leaving clean-finished edges at the road base.

Another object of the invention is to provide a road base building apparatus in which the windrow splitters or plows, the reciprocating rakes, the spreading shovels,

and the reciprocating screeds are transversely movable to provide the operator with a means for precisely controlling the spreading and leveling of material.

Other objects and features of the invention will become apparent from consideration of the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view' of the road base building FIG. 5 is a detail View taken along the line 55 of FIG. 3, and illustrating a portion of the drive means for the rear screed;

FIG. 6 is an enlarged, rear elevational view, taken along the line 66 of FIG. 2, illustrating a portion of the means for adjusting the height of the reciprocating rakes;

FIG. 7 is a view taken along the line 77 of FIG. 6;

FIG. 8 is an enlarged, front elevational view, taken along' the line 88 of FIG. 2, illustrating the means for adjusting the height of the rear screed;

FIG. 9 is a view taken along the line 9-9 of FIG. 8;

FIG. 10 is a top plan view, on an enlarged scale, illustrating the front, left track drive unit;

FIG. 11 is an enlarged, front elevational view of the track drive unit of FIG. 10;

FIG. 12 is an enlarged, side elevational view, taken along the line 1212 of FIG. 2, illustrating a portion of the means for transversely moving the forward or front spreading shovel;

FIG. 13 is a FIG. 12;

FIG. 14 is a view taken along the line 1414 of FIG. 13; and

FIG. '15 is an enlarged, side elevational view, taken along the line 15-15 of FIG. 2, illustrating the means for adjusting the vertical height of the V-plows or windrow splitters.

GENERAL ARRANGEMENT Referring now to the drawings, and particularly FIGS. 1 through 3 thereof, a road base rbuilding apparatus 10 according to the present invention is illustrated as it would appear when traveling forwardly, in the direction of the arrow 12. The apparatus 10 includes a rigid rectangular frame 14 which is supported by a pair. of

view taken along the line 13-13 of transversely spaced-apart front tracks 16 and a pair of transversely spaced-apart rear tracks 18, whereby the apparatus is self-propelled, as will be seen.

Although the apparatus 10 is adapted to be utilized as a heavy-duty, accurate subgrader, thedescri-ption hereinafter made Will be directed to utilization of the apparatus 10 for spreading and leveling of base course material upon an already prepared subgrade. The base course for a concrete highway is usually a rock base over which the slab of concrete is liad. However, it-should be noted that the present apparatus 10 is adapted to spread and level various types of base course materials, as Well as cement-treated material which itself constitutes the road surface, and the description hereinafter made is therefore merely exemplary.

Since the accuracy of the grade of the rock base course to a great extent controls the accuracy of the finished road, it is extremely important to break up, spread, and level the rock base course within relatively close tolerances.

The rock base material is usually dumped into a pair of conventional calibrated windrowers (not shown) by a pair of dump trucks. The windrowers lay down two parallel windrows arranged coextensive with and upon the proposed road bed, and theapparatus 10 desegregates, spreads, and levels the two windrows to provide a finished rock base course for supporting an overlying slab of concrete to form the road.

The forward extremity of the frame 14 carries a pair of transversely spaced-apart windro-w splitters or V-plows 20 which split and laterally distribute the two windrows of rock base material across the width of the apparatus 10. In a typical instance the material is spread to a loose depth of about 4 /2 inches across a lateral span of 27 feet.

On the frame 14 rearwardly of the V-plows 20 are a pair of reciprocating rakes 22 and 24 which desegregate or work the rock base material to a uniform consistency by reciprocating through the material in a transverse direction with a stroke of, for example, approximately 7 inches.

Mounted on the frame -14 rearwardly of the reciprocating rakes 22 and 24 isa chain-driven forward spreader paddle or shovel 26 which ordinarily moves constantly across the width of the apparatus 10 to provide lateral distribution of the rock material.

To the rear of the shovel 26 the frame 14 mounts a toothed, transversely reciprocating forward or front screed 28 which effects leveling and smoothing of the rock material which was laterally positioned by the shovel 26. A chain-driven second or rear spreader shovel 30 is mounted to the frame 14 behind the front screed 28 and normally moves continuously back and forth across the width of the apparatus 10 to effect a finer lateral distribution of the material leaving the front screed 28, picking up the material from the high or heavy spots and delivering it to the low or lean spots.

On the frame 14 behind the rear shovel 30 is located a transversely reciprocating finish or rear screed 32 characterized by a straight lower edge to impart an accurate, finished surface to the base course material as the apparatus 10 proceeds beyond it.

As will be seen, each of the above-mentioned components is individually adjustable to perform its function in a manner tailored to the particular job to be done.

The frame The frame .14 includes a pair of longitudinally extending

side members

34 and 36 integrally connected by front and rear cross pieces or

beams

38 and 40 as well as a plurality of intermediate transverse beams 42. The

members

34 and 36 and the

beams

38, 40 and 42 may be secured together in any suitable fashion, as by welding or bolting together, but the latter is preferred because it facilitates shipping and transportation of the apparatus 10. Moreover, the

beams

38, 40 and 42 are preferably made in bolted-together sections to permit relatively rapid disassemb-ly thereof for changing the apparatus 10 from one width to another to accommodate the apparatus to construction of roads of different widths.

The frame 14 is also suitably reinforced by various bracing components, including a pair of side trusses 44, but such bracing components will not be described in detail inasmuch as their particular construction does notform a part of the present invention.

An internal combustion engine 46 is centrally located over the

screeds

28 and 32 upon a pair of the intermediate frame beams 42. As best illustrated in FIG. 2, the engine 46 is coupled to a gear box 48 for altering the input speed to the driven components of the apparatus 10, and the box 48 is in turn coupled to a usual and conventional differential '50, FIG. 3, for driving the tracks 16 and 18. The engine 46 is also coupled to a hydraulic pump 52 to supply fluid under pressure for operation of the various hydraulic components of the apparatus 10, the pump 52 being conventional in construction with its output controlled by conventional valving to actuate various hydraulic cylinders, as will be seen. Most of the details of structure of the engine 46, the gear box 48, the differential 50, the pump 52, and the means interconnecting these units are not described herein for reasons of brevity, because such details form no part of the present invention, and because such details will immediately suggest themselves to those skilled in this art.

The engine 46 is connected by a system of belts and chains to the components driven thereby, as best viewed in FIG. 3, which system is connected to a drive shaft 54 of the engine 46. The shaft 54 rotates a grooved sheave 56 which is connected to a grooved differential sheave 58 and to a drive sheave 60 by separate pluralities of V-belts.

The sheave 58 drives the differential 50 through a chain sprocket 62 connected to the differential 50 by a chain 64, the opposite sides of the diiferental 50 being keyed to a pair of shafts 6'6 and 68 which have their opposite ends keyed to a pair of chain sprockets 70 and 72, respectively. The sprockets 70 and 72 are rotatably supported by the side frame members 36 and 54, respectively, and drive pairs of endless chains coupled to the tracks 16 and 18. These chains are constituted by a rearwardly extending endless chain 74 and a forwardly extending endless chain 76 meshed with the sprocket 70, and a rearwardly extending endless chain 78 and a forwardly extending endless chain 80 meshed with the sprocket 72. The

chains

76 and 80 are operatively coupled to the front tracks 16 and the chains 74 and 78 to the rear tracks 18 where the apparatus 10 is propelled forwardly or rearwardly depending upon the direction of rotation of the drive sprocket 62 of the differential 50.

A representative showing of the coupling of the endless drive chains 74, 7:6, 78 and 8th is seen'in FIG. 3, wherein the chain 74 is shown meshed with a track sprocket-82 connected by a universal joint linkage 84 to a sprocket 86. The sprocket '86 is connected by an endless chain 88 to a track sprocket 90 mounted on a shaft which carries an endless track chain (not shown) for a rear track :18. The track chain meshes with sprockets carried by toothed wheels upon which the track threads 92 are carried, as best viewed in 'FIGS. 10 and 11. Thus, the engine 46 is adapted to power the front and rear tracks 16 and 18 forwardly or rearwardly, depending upon operation of the gear box 48, to move the apparatus 10 over the proposed road bed.

The engine 46 is also adapted to effect reciprocatory transverse movement of the front and

rear screeds

28 and 30 by coupling of the drive sheave 60 to a shaft 94. The shaft 94 drives a chain sprocket 96 connected by a chain 98 to another chain sprocket 100 which drives a shaft carrying a chain sprocket 102. This drives an endless chain 104 connected to a screed sprocket 106, which rotates a pair of shafts 108 and 110 carrying a pair of crank arms 112 and 114, respectively. The crank arms 112 and 114 are connected to a pair of transversely disposed

screed shafts

116 and 118, respectively, for transversely reciprocating the front and

rear screeds

28 and 30.

The engine 46 is also adapted to operate the reciprocating rake 22 through connection of the chain sprocket 96 to a grooved sheave'120 which is connected by a plurality of Vbelts to a groove-d sheave 122. Rotation of the sheave 122 is transmitted by a shaft 124 to a chain sprocket 126, and the .rotation is then carried by an endless chain 128 to a chain sprocket 130 which is mounted at approximately the midportion of a shaft 132. The opposite extremities of the shaft 132 are keyed to a pair of chain sprockets 134 and 136 so that the sprockets 134 and 136 are rotatable by the sprocket 130. Sprocket 130 is also effective to rotate a chain sprocket 138 which is mounted upon the shaft 132 outwardly of the chain sprocket 134, and is operative with the sprocket 136 to power the

shovels

26 and 30, respectively, as will be seen.

The chain sprocket 134 is connected by an endless chain 140 to a chain sprocket 142 which, through a shaft 144, rotates a crank throw .146, as best viewed in FIG. 4. The crank throw 146 is pivotally mounted to a transversely extending rake shaft 148 connected to the reciprocating rake 22 for reciprocating the same, as will be seen.

The front and

rear shovels

26 and 30 are moved transversely by the sprockets 138 and 136 through a pair of endless chains 150 and 1 52 which convert rotation of the sprockets into transverse movement of the shovels, as will be seen, the chains being held at the opposite sides of the frame 14 by training thereof upon a pair of idler sprockets 154 and 156 rotatably mounted to the frame 14.

Each of the tracks 16 and 18 is attached to the frame 14 in such a way that the track may be steered as well as vertically adjusted. More particularly, each track, as best viewed in FIGS. and 11, is constituted by a cyl inder 158 which is attached to the frame front beam 38 by a short, U-shaped channel member 160 welded to the front beam 38. Across the upper end of the cylinder 160 is welded a strap 162 having a central opening for receiving a threaded shaft 164. A nut 166 is welded to the strap 162 so that rotation of the shaft 164 serves to vertically position the shaft 164 relative to the cylinder 158.

The lower end of the shaft 164 is freely rotatable in a collar 168 welded to a yoke 170 which rotatably mounts the sprocket 90 of the track. A cylinder 172 is welded at its lower end to the yoke 170 and is slidable at its upper end within the cylinder 158. Thus, rotation of the shaft 164 in one direction will raise the frame 14 relative to the track 16, while rotation of the shaft 164 in the opposite direction permits the weight of the frame 14 to lower the frame 14 relative to the track 16. To

prevent the cylinder 172 from sliding downwardly out of the cylinder 158 when the frame 14 is raised, as bya crane during transportation or the like of apparatus 10, a chain 174 is connected between the two

cylinders

158 and 172, as best illustrated in FIG. 11.

Each track is steered by a pair of steering arms 176 and 178 connected at their forward extremities to the yoke 170, and diverging rearwardly for connection together and for pivotal connection to a transversely extending steering rod 180 disposed between the steering arms 176 of the oppositely disposed tracks 16 or 18, as the case may be.

The steering rod 180 is moved in one direction or the other by a double-acting hydraulic cylinder 182 suitably connected between the steering rod 180 and the frame 14. As will be apparent, the cylinder 182 is appropriately connected by suitable flexible conduits to the hydraulic pump 52, and is under the control of the operator by means of suitable valving (not shown).

V-plows Each of the pair of V-plows 20 located at the forward extremity of the apparatus 10 comprises a pair of elongated, rearwardly diverging plow plates 184 whose forward extremities are secured to a short, longitudinally extending plate 186. The rearward extremities of theplow plates 184 are welded together in divergent relationship by a transversely extending channel 188, and a transversely extending strap is welded adjacent the forward extremities of the blades 184 to provide an integral, rigid structure.

As best viewed in FIGS. 1, 2, and 15, a pair of transversely spaced-apart plow supports 192 are connected to each of the plow channels 188 to support the plows 20 upon the most forwardly located intermediate beam 42. As best viewed in FIG. 15, each plow support 192.includes a bracket 194 welded to the plow channel 188 and keyed to the lower extremity of a vertically extending shank 196 which slidably passes through vertically aligned openings provided in a support channel 198 which encompasses the intermediate channel or beam 42.

The upper extremity of the shank 196 is slidably disposed through a cylindrical housing 200 welded to the upper side of the support channel 198. A nut 202 is mounted to a threaded upper end of the shank 196, and bears against the upper end of the housing 200 whereby rotation of the nut 202 in opposite directions raises and lowers the shank 196 relative to the bracket support channel 198. With this arrangement, a means is provided for relatively rapidly adjusting the height of the rearward extremities of the plow blades 184 above the road surface, as by merely rotating the nut 202 in the proper direction. Each plow support 192 is secured in position upon one of the intermediate beam-s 42 by a set screw- 204 and a usual lock nut 206, as will be apparent.

An identical plow support 192 is located adjacent the forward extremity of each plow 20, and is mounted upon the front beam 38 with the lower end of its shank welded to the plate 186. Accordingly, both the rearward and forward extremities of the plows 20 may be accurately adjusted with respect to the surface to be. Worked whereby an optimum distribution of the base course material is had.

The initial windrow splitting angle of each of the plows 20 is hydraulically adjustable so that the base course material is spread or laterally distributed in the most advantageous manner. More particularly, each plow 20 includes a splitter plate 208 pivotally connected to the forward end of the plate 186 and including an integral operating arm 210 which is pivotally connected to the piston of a double-acting hydraulic cylinder 212 pivotally secured to the transverse strap 190 as best viewed in FIG. 2. The cylinders 212 of the two plows 20 are suitably connected to the hydraulic controls of apparatus 10 so that the operator is able to precisely split the windrows as required by the particular application at hand whereby complete flexibility is provided in the splitting and lateral distribution of the windrows of base course material.

Reciprocating rakes The laterally distributed base course material passing from the V-plows 20 is next agitated and desegregated by the transversely extending reciprocating rakes-22 and 24. As best viewed in FIGS. 1 through 4, 6, and 7,

the

rakes

22 and 24 extend transversely in coextensive relationship, and are substantially identical so that a description of one will serve as a description of the other as well. Thus, the rake 22 comprises a transverse support bar 214 extending substantially the whole width of the frame 14, and including a plurality of equally spacedapart openings which receive a corresponding plurality of vertically oriented, elongated elements or teeth 216 secured in position by bolts 218.

The support bar 214 is rigidly secured to the lower end of a pair of transversely spaced-apart cylinders 220, one of which is illustrated in FIGS. 6 and 7. The cylinders 220 are vertically slidable within larger cylinders 222 which are welded to and form integral parts of a pair of pivot assemblies 224. Each assembly 224 also includes a cylinder 226 opposite the cylinder 222 for slidably accommodating the cylinder 220 of the other rake 24. The two cylinders 222 and 226- of each assembly 224 are connected by a pair of upper and lower plates 228 to opposite sides of an upper annular collar 230 and a lower annular collar 232 which are pinned to the upper and lower extremities of a cylinder 234.

The cylinder 234 is rotatable within a fixed, larger cylinder 236 rigidly secured to an arcuate yoke 238 welded to the intermediate beam 42. With this arrangement, the central cylinder 234 and the pair of cylinders 220 pivot relative to the fixed yoke 238 and the cylinder 236, effecting a reciprocatory movement of the rake teeth 216 of both of the

rakes

22 and 24.

Pivoting of the pair of pivot assemblies 224 to reciprocate the

rakes

22 and 24 is produced by the rake shaft 148 which was previously mentioned in connection with the components illustrated in FIG. 3. The shaft 148 is connected to the cylinder 222 by a ball joint connection 239 and is reciprocated by rotation of the crank throw 146 at approximately 75 revolutions per minute, with a length of stroke of the shaft 148 of approximately seven inches. Of course, such speed and stroke is merely exemplary of one arrangement which was found to work the'rock base course material to a uniform. consistency with minimum segregation.

The lowermost position of the teeth 216 of each of the

rakes

22 and 24 is adjusted by rotation of a pair of nuts 240 upon the threaded upper extremities of the cylinders 220, thereby adjusting the positions of the cylinders 220 relative to the

cylinders

222 and 226 within which they are vertically slidable.

The vertical positions of the teeth 216 are also vertically adjustable during operation of the apparatus 10 by meansof flexible cables which are connected to a hydraulic cylinder. More particularly, a flexible cable 242 is secured to a pair of cables 244, only one of which is illustrated in FIG. 6, which are secured to the support bars 214 of the

rakes

22 and 24. The cable 242 is trained about a pulley 246 rotatably mounted to the intermediate beam 42, and extends transversely to a singleacting hydraulic cylinder 248, FIG. 2. A similar cable is also extended from the other extremity of the

rakes

22 and 24 for connection to the hydraulic cylinder 248 so,

that by operating suitable valves (not shown), the operator of the apparatus 10 is able to control the hydraulic Forward shovel As best illustrated in FIGS. 1, 2, and 12 through 14,

the forward shovel 26 is transversely movable forwardly of the intermediate beam 42 and across the width of the apparatus 10. The structure supporting the shovel 26 during this movement includes a plurality of transversely spaced apart brackets (not shown in detail) which are welded to the forward face of the beam 42 and support a pair of vertically spaced apart, horizontally extending

angles

250 and 252 which, as will be seen, constitute tracks for guiding the shovel 26 in its transverse travel.

The shovel 26 comprises a pair of angularly inclined blades 254 which diverge in a rearward direction and are secured at their midportions in spaced apart relationship by channel members 256 Welded to the lower extremity of a hollow vertically extending shovel support element 258. The element 258 is vertically slidable within a similar hollow, but larger support element 260* which is welded to a vertical mounting plate 262.

A pair of spaced apart upper rollers 264 and a pair of spaced apart lower rollers 264 are rotatably carried by the plate 262, being secured to the back thereof by mounting bolts or the like (not shown), and roll upon the

angles

250 and 252. The rollers 264 include annular end flanges which retain the rollers on the

angles

250 and 252.

The shovel 26 is raised and lowered by a hydraulic actuator or cylinder 266 disposed Within the

telescopable elements

258 and 260, the upper extremity of the cylinder 266 being secured to the upper extremity of the cylinder 260 by a transversely disposed pin 268, and the lower ex-v tremity of the cylinder 266 being secured tothe transverse channels 256 by a pin 270. However, the openings in the various components accommodating the pin 270 are oversize, and a compression spring 272 is disposed between the channels 256 and a shoulder 274 of the cylinder 258 to resiliently take up the relative movement occasioned by the loose fitting pin 270. The resilient mounting of the shovel 26 permits the shove-l blades 254 to orient themselves as required for coextensive engagement with the road bed surface over whic hthe apparatus 10 is passmg.

If it is desired to lower the shovel 26, hydraulic fluid is directed into a hydraulic line 276 and into the cylinder 266, as by manipulation of suitable control valves (not shown) forcing the piston 278 thereof to move downwardly. In similar fashion, the shovel 26 is moved upwardly by exhausting fluid through the line 276, the

natural forces on the shovel 26 during operation of the apparatus 10 tending to push the shovel upwardly.

Thus, the shovel 26 is movable transversely as well as up and down, whereby the operator exercises close control of the lateral spreading of base course material coming from the

reciprocatingrakes

22 and 24. Accordingly, if the operator wishes to deposit some of the material to one side of the apparatus 10, it is merely necessary to lower the shovel 26 at the opposite side and gradually raise it as the shovel approaches the side of the apparatus where more of the material is desired. Gther discrepancies in material distribution are similarly adjusted, as will be apparent.

The transverse movement of the shovel 26 is primarily effected through the operation of a continuous chain 280 which is rotatably mounted upon a pair of sprockets (not shown) located at opposite sides of the apparatus 10, and rotatably secured to the forward face of the intermediate beam 42. A flanged guide wheel 282 is rotatably carried by the chain 280, as best illustrated in FIG. 12, and is projected forwardly by the chain within a vertical track 284 defined by a pair of vertically arranged elements secured to the rear face of the mounting plate 262.

With this arrangement, as the chain 280 passes about its sprockets, the guide wheel 282 in engagement with the track 284 carries the shovel 26 toward one side of the apparatus 10. When the chain 280 passes about its end sprocket at that point, the guide wheel 282'will follow the chain and move upwardly or downwardly in the track 284, as the case may be, and thereafter carry the shovel 26 in the opposite direction across the width of the apparatus 10. In this manner, the shovel 26 continuously'moves back and forth to distribute the base course material.

Rear shovel The rear shovel 30, which is located between the front and

rear screeds

28 and 32, is substantially identical in arrangement and operation to the front shovel 26 just described except that the shovel blades thereof are somewhat smaller and are joined together at their forward extremities in a V configuration. The rear shovel 30 provides an accurate lateral distribution of base course material passing from the front screed 28, and gives the operator a fine control of the grade of the base course material just before its final leveling by the rear screed 32. The rear shovel 26 is indicated in dotted outline in FIG. 2, and is transversely movable along a track 286 mounted upon an intermediate beam 288 disposed between the

frame side members

34 and 36, in a manner substantially identical to the transverse. track provided for the front shovel 26 by the

angles

250 and 2 52 upon the intermediate beam 42.

Front and rear screeds The front screed 28 and the rear screed 32 are substantially identical in construction and operation except that the front screed is reciprocated by the shaft 116 and the rear screed by the shaft 118, and also in that the screeds are differently positioned. Accordingly, a detailed de scription will be made of only the rear screed 32, the

description being equally applicable to the front screed 28 unless otherwise indicated.

The rear screed 32 includes an elongated horiozntal scraper element 290 extending across the width of the apparatus and, as best vie-wed in FIGS. 8 and 9, is characterized by a straight lower edge. In contrast, the front screed 28 has an elongated scraper element which is toothed to more easily handle the initial leveling of the base course material. The straight scraper element 290 is best adapted to effect the final finishing in that it provides a smooth surface.

The scraper element 290 is welded to the forwardlower edge ofan elongated screed box 292 whose walls are welded together to form a hollow, transversely extending box structure, as best viewed in FIG. 1. The box 292 is supported by an intermediate beam 294 carried -by the frame side members 34'and 36, a pair of shafts 296 being rigidly secured to the opposite extremities of the box 292 and extending upwardly into a pair of cylindrical fittings 298 which aid in suspending the screed in position while allowing reciprocation thereof.

More particularly, the upper extremity of each of the pair of shafts 296 is rotatable in its fitting 298, passes through a suitable opening provided in a plate 300 which is welded across the upper end thereof, and is threaded to receive a pair of wrench nuts 302. The nuts 302 are operated to adjust the vertical position of the shaft 296 relative to the cylindrical fitting 298, and lock the shaft and fitting in the adjusted positions thereof. By thus operating the two pairs of nuts 302, the vertical position of the opposite ends of the screed may be adjusted.

Each cylindrical fitting 298 is welded to a support arm 304 which is welded to a vertically oriented shaft 306. The upper and lower ends of the shaft 306 are rotatably carried in annular upper and

lower trunnions

308 and 310 bolted to a box frame 312 which is welded to the upper side of the intermediate beam 294. Thus, each cylindrical fitting 298 is integral with a shaft 296, and is rotatable relative to the associated cylindrical trunnion 308.

The rear screed 32 is transversely reciprocated by reciprocatory movement of the shaft 118 which is connected to one extremity of the screed box 292, as best illustrated in FIG. 5. More particularly, the shaft 118 is slidably disposed through an annular tube 314, is carried by the screed 32, the tube 314 including an integral shaft portion 316 rotatably carried Within a cylinder 318 welded to the upper side of the screed box 292.

A pair of springs 320 are arranged upon the shaft 1 18 on opposite sides of the tube 314, and are maintained in position by a pair of collars 322 secured to the shaft 118. When the shaft 118 moves in one direction, one of the springs 320 is compressed, followed by movement of thescreed 32 in that direction. Conversely, when the shaft 118 is moved in the opposite direction, the other spring 320 is compressed, followed by movement of the screed 32 in such opposite direction. Thus, the movement of the screed 32 in either direction is first cushioned by initial compression of the springs 320, thereby reducing shock and smoothing the reversal of direction of the screed 32 during reciprocation of the screed shaft 118.

In addition to the height adjustment provided by the nut wrenches 302, the screed 32 is vertically movable by means of a pair of hydraulic cylinders 324 secured to the box spring 312. The piston ends thereof are secured to the lower wall of the screed box 292 by means of a pair of chains 326 whose lengths are initially established such that the screed 32 is in operative engagement with the base course material in its lowermost position and out of engagement with such material in its uppermost position. Accordingly, operation of the cylinders 324 raises and lowers the screed 32 between its operative and inoperative positions as the apparatus 10 is propelled over the roadbed, and operation of only one of the cylinders 324 effects a tilting of the screed.

From the above description, it will be apparent that the apparatus '10 is effective to accurately spread and level base course material for a road, to also spread and level cement treated material, and to also actually prepare the subgrade itself. The apparatus is self propelled to follow conventional windrowers, and split, spread and level the windrows to provide a roadbed of accurate grade. The utilization of the pair of large, rugged V-plows 20 enables the apparatus to handle large quantities of material, splitting and laterally spreading the material to an initial rough grade.

The pair of transversely reciprocating rakes deseg'regate the material and break it into particles of substantially uniform size, providing a uniform roadbed, and the continuously moving forward shovel effects an initial transverse distribution of the material for initial leveling by the forward screed. Thereafter, the continuously moving rearward shovel provides a more precise lateral distribution of the material prior to final leveling by the rearward screed. In this regard, the transverse reciprocation of the forward and rearward screeds greatly assists in properly leveling the material, and the ability of the operator to raise and lower either of the shovels at any time gives him a very precise control over the lateral distribution 'of the material before it ever reaches the screeds.

Various modifications and changes may be made with regard to the foregoing detailed description without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. A road 'base building apparatus comprising:

a frame;

V-plow means mounted to said frame for laterally distributing road base material on a highway subgrade;

a pair of toothed rakes pivotally mounted on said frame rearwardly of said V-plow means for transverse reciprocation in opposite directions relative to each other;

means for pivoting said rakes for transversely reciprocating the teeth of said rakes .in said road base material;

shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally distribute road base material leaving said toothed rakes;

screed means pivotally mounted on said frame rearwardly of said shovel means;

means for transversely reciprocating said screed means to level said road base material; and

drive means for simultaneously propelling said frame over said subgrade, transversely moving said shovel means, and actuating said means for pivoting said rakes and actuating said means for reciprocating said screed means whereby a strip of road base material of uniform height and consistency may be continuously provided.

2. A road base building apparatus comprising:

a frame;

V-plow means mounted to said frame for laterally distributing road base material on a highway subgrade, a portion of said V-plow means being pivot- 11 able on said frame to adjust the amounts of said road base material laterally distributed on opposite sides of said V-plow means;

means for pivoting said rakes for transversely reciprocating the teeth of said rakes in said road base material;

shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally 'distribute road base material leaving said toothed rakes;

screed means pivotally mounted on said frame rearwardly of said shovel means;

drive means for simultaneously propelling said frame over said subgrade, transversely moving said shovel means, actuating said means for pivoting said rakes, pivoting said portion of said V-plow means, and actuating said means for reciprocating said screed means whereby a strip of road base material of uniform height and consistency may be continuously provided. v

3. A road base building apparatus comprising:

a frame;

first shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally distribute road base material leaving said toothed rakes;

first screed means pivotally mounted on said frame rearwardly of said first shovel means;

means for transversely reciprocating said first screed means to level said road base material;

second shovel means on said frame rearwardly of said first screed means and transversely movable on said frame to laterally distribute road base material leaving said first screed means;

second screed means pivotally mounted on said frame rearwardly of said second shovel means;

means for transversely reciprocating said second screed means to level said road base material;

means for transversely reciprocating said second screed means to level said road base material distributed by said second shovel means; and

drive means for simultaneously propelling said frame over said subgrade, transversely moving said first and second shovel means, actuating said means for pivoting said rakes, actuating said means for reciprocating said first screed means, and actuating said means for reciprocating said second screed means whereby a strip of road base material of uniform height and consistency may be continuously provided.

4. A road base building apparatus comprising:

a frame;

shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally dsitribute road base material leaving said toothed rakes, said shovel means being vertically movable to adjust the depth of penetration of said road base material by said shovel means;

means including hydraulic cylinder means connected between said frame and said shovel means and operable to raise and lower said shovel means;

screed means pivotally mounted on said frame rearwardly of said shovel means;

drive means for simultaneously propelling said frame over said subgrade, transversely moving said shovel means, and operating said means for pivoting said rakes and said means for reciprocating said screed means whereby a strip of road base material of uniform height and consistency may be continuously provided.

5. A road base building apparatus comprising:

aframe;

means for pivoting said rakes for transversely reciprocating the teeth of said rakes in said road base material, said toothed rakes being vertically movable to adjust the depth of said teeth in said road base material;

means including hydraulic cylinder means connected between said frame and said toothed rakes and operable to raise and lower said toothed rakes;

screed means pivotally mounted on said frame rearwardly of said shovel means;

6. A road base building apparatus comprising:

a frame;

V-plow means mounted to said frame for later-ally means for transversely reciprocating said screed means to level said road base material, said screed means being vertically movable to adjust the height of said lower edge;

means including hydraulic cylinder means connected between said frame and said screed means and operable 'to raise and lower said lower edge of saidscreed means; and 7 drive means for simultaneously propelling said frame over said subgrade, transversely moving said shovel means, and operating said means for pivoting said rakes and said means for reciprocating said screed means whereby a strip of road base material of uniform height and consistency may be continuously :provided.

7. A road base building apparatus comprising:

a substantially rectangular frame having a pair of spaced apart side members;

a pair of V-plow means mounted to said frame in adjacent, transversely spaced apart relationship for laterally distributing road base material on a highway subgrade, each of said -V-plow means pivotally mounting a vertically oriented forward plate;

means including hydraulic cylinder means for pivoting said plate of each of said V-plow means to thereby adjust the lateral distribution of said road base material;

a pair of elongated, substantially coextensive toothed rakes mounted on said frame rearwardly of said pair of V-plow means and pivotable on opposite sides of common pivot points for transverse reciprocation in opposite directions relative to each other;

means for pivoting said rakes for transversely reciprocating the teeth thereof in opposite directions in said road base material;

screed means pivotally mounted on said frame rearwardly of said shovel means;

8. A road base building apparatus comprising:

a substantially rectangular frame having a pair of spaced apart side members;

a pair of V-p-low means mounted to said frame in adjacent, transversely spaced apart relationship for laterally distributing road base material on a highway subgrade, each of said V-plow means pivotally mounting a vertically oriented forward plate;

a pair of elongated, substantially coextensive toothed rakes mounted on said frame rearwardly of said pair of V-plow means and pivotable on opposite sides of common pivot points for transverse reciprocation in opposite directions relative-to each other;

means for pivoting said rakes for transversely reciprocating the teeth thereof in opposite directions in-said road base material;

a pair of shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally distribute road base material,

one of said pair of shovel means being located immediately rearwardly of said toothed rakes;

a pair of screed means pivotally mounted on said frame forwardly and rearwardly, respectively of the rearmost one of said pair of shovel means;

a pair of means for transversely reciprocating said pair of screed means, respectively, to level said road base material; and

drive means for simultaneously propelling said frame over said subgrade, transversely moving said shovel means, operating said means for pivoting said rakes, and operating said pair of means for reciprocating said pair of screed means whereby a strip of road base material of uniform height and consistency may be continuously provided.

9. A road base building apparatus comprising:

a substantially rectangular frame having a pairof spaced apart side members;

a pair of V-plow means mounted to said frame in adjacent, transversely spaced apart relationship for lateral-1y distributing road base material on a highway subgrade, each of said V-plow means pivotally mounting a vertically oriented forward plate;

a pair of elongated, substantially coextensive toothed rakes mounted on said frame rearwardly of said pair of V-plow means and pivotable on opposite sides of common pivot points for transverse recip rocation in opposite directions relative to each other;

a pair of shovel means on said frame rearwardly of said toothed rakes and transversely movable on said frame to laterally distribute road base material, one of said pair of shovel means being located immediately rearwardly of said toothed rakes;

a pair of screed means pivotally mounted on said frame forwardly and rearwarly, respectively of the rearmost one of said pair of shovel means;

a pair of means for transversely reciprocating said pair of screed means, respectively, to level said road base material, the lower edge of said rearmost screed means being straight and the lower edge of the other of said pair of screed means being toothed; and

drive means simultaneously propelling said frame over said subgrade, transversely moving said shovel means, operating said means for pivoting said rakes, and operating said pair of means for reciprocating said pair of screed means whereby a strip of road base material of uniform height and consistency may' be continuously provided.

10. A road base building apparatus comprising:

a frame;

V-plow means mounted to said frame for laterally distributing road base material on a highway subgrade; v

screed means pivotally mounted on said frame rearwardly of said shovel means;

means for transversely reciprocating said screed means to level said road base material;

a plurality of tractor means located adjacent the sides of said frame and operative to propel said frame over said subgrade; and

means for operating said tractor means, for transversely moving said shovel means, and for actuating said means for pivoting said rakes and actuating said mieans for reciprocating said screed means whereby a strip of road base material of uniform height and consistency may be continuously provided.

References Cited by the Examiner UNITED STATES PATENTS Fitzgerald 94-45 Humphries 9444 Noble 9444 Heltzel 94-44 Heltzel 9444 Faber 9444 Millikin 94-46 Apel 9445 JACOB L. NACKENOFF, Primary Examiner.

Claims

1. A ROAD BASE BUILDING APPARATUS COMPRISING: A FRAME; V-PLOW MEANS MOUNTED TO SAID FRAME FOR LATERALLY DISTRIBUTING ROAD BASE MATERIAL ON A HIGHWAY SUBGRADE; A PAIR OF TOOTHED RAKES PIVOTALLY MOUNTED ON SAID FRAME REARWARDLY OF SAID V-PLOW MEANS FOR TRANSVERSE RECIPROCATION IN OPPOSITE DIRECTIONS RELATIVE TO EACH OTHER; MEANS FOR PIVOTING SAID RAKES FOR TRANSVERSELY RECIPROCATING THE TEETH OF SAID RAKE IN SAID ROAD BASE MATERIAL; SHOVEL MEANS ON SAID FRAME REARWARDLY OF SAID TOOTHED RAKES AND TRANSVERSELY MOVABLE ON SAID FRAME TO LATERALLY DISTRIBUTE ROAD BASE MATERIAL LEAVING SAID TOOTHED RAKES; SCREED MEANS PIVOTALLY MOUNTED ON SAID FRAME REARWARDLY OF SAID SHOVEL MEANS; MEANS FOR TRANSVERSELY RECIPROCATING SAID SCREED MEANS TO LEVEL SAID ROAD BASE MATERIAL; AND DRIVE MEANS FOR SIMULTANEOUSLY PROPELLING SAID FRAME OVER SAID SUBGRADE, TRANSVERSELY MOVING SAID SHOVEL MEANS, AND ACTUATING SAID MEANS FOR PIVOTING SAID RAKES AND ACTUATING SAID MEANS FOR RECIPROCATING SAID SCREED MEANS WHEREBY A STRIP OF ROAD BASE MATERIAL OF UNIFORM HEIGHT AND CONSISTENCY MAY BE CONTINUOUSLY PROVIDED.