US2241299A

US2241299A - Road building apparatus

Info

Publication number: US2241299A
Application number: US171979A
Authority: US
Inventors: Sam E Finley
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-10-30
Filing date: 1937-10-30
Publication date: 1941-05-06
Anticipated expiration: 1958-05-06

Description

S. E. FINLEY ROAD BUILDING APPARATUS Mayfi, 1941. v

5 Sheets-Sheet 1 Filed Oct. 50. 1937 May 6, 1941. 5 E. FINLEY 2,241,299

ROAD BUILDING APPARATUS Filed Oct. 30, 1937 5 Sheets-Sheet 2 May 6, 1941.

S. E. FlNLEY ROAD BUILDING APPARATUS Filed Oct. 30, 1937 5 ShoetsSheet 3 May 6, 1941. s. E. FINLEY ROAD BUILDING APPARATUS 5 Sheets-Sheet 4 Filed Oct 30, 1937 May 6, 1941. 5 E FINLEY 2,241,299

ROAD BUILDING APPARATUS Filed Oct. 30, 1937 5 Shets-Sheet 5 I I 1 I I I I 0 r" 7 1 n N l W. N m J n v I III 3. I w [I I I I; I n

4 a 8 @Q 51 m v' y,

II v Patented May 6, 1941 UNITED STATES PATENT OFFICE ROAD BUILDING APPARATUS Sam E. Finley, Atlanta, Ga.

Application October 30, 1937, Serial No. 171,979

Claims.

This invention relates to road building apparatus and more particularly to machines for heating, mixing and spreading aggregates, previously coated with bituminous material, in place upon the road bed.

A process of building roads of bituminous-coated aggregate, whether as a road built upon a natural foundation or as a paving upon an old, worn road surface, or upon another road base previously formed, has come into general use and has been commonly termed the mixed-in-place process, the standard practice according tosuch process being to spread on the road foundation broken stone, slag, gravel and the like, in pieces of suitable sizes, and to apply bitumen thereto by means of a pressure distributor. In order to obtain workability of the aggregate, with such process, it is necessary that the bitumen contain a high percentage of quick volatiles, such as naphtha and asphaltic cement cut backs, and that the particles of aggregate be of such size that the interstices therebetween will afford a means of exit permitting the volatilized matter to escape, in order that the roadway can set up into a bituminous wearing surface. This process has the definite disadvantage that it effects a paving of the kind known to those skilled in the art as of the open type, and the same openings or interstices that provide for the escape of volatile matter persist to a marked degree and permit the subsequent entrance of water which, in many instances, softens the foundation or causes the bituminous wearing surface to be broken up. Such process likewise entails high economic waste, since the volatile compounds, necessary to provide workability of the coated aggregate, constitute the most expensive part of the mixture and are almost totally lost. Such process also usually entails excessive time and labor, because in most instances the machine used in such mixed-inplace process must make several trips over the roadway in order to effect a mix that is even approximately perfect.

One of the objects of the invention is to provide an apparatus for building a road of bituminous material containing a. minimum of volatile compounds. A further object is to provide such an apparatus that will produce a bituminous wearing surface economically as to time, labor and materials, and that will be durable and highly resistant to penetration by water.

A still further object is to provide an apparatus by which fine aggregates that cannot be utilized in the usual road building methods can be employed, with the advantage of effecting a surface that is particularly dense and impermeable.

Further objects of the invention will be apparent from reference to the following specification and the accompanying drawings, wherein the apparatus is described and illustrated.

In general, in accordance with the present invention, aggregates of the desired quantity are spread upon the surface to be paved, whether the same be top soil, clay, gravel, water-bound macadam, Portland cement or any other usual road foundation, such aggregates being coated with bituminous cement heated to a high temperature, and the coated aggregates are then thoroughly mixed in place on the road foundation and while maintained at a high temperature, by an apparatus, such as that shown in the drawings, which is moved over the roadway and is provided with inclined blades maintained at a high temperature and so designed that the aggregates are heated not only by the heated blades but also by the gaseous products of combustion of the fuel used to heat the blades. The initial coating of the particles of aggregate with heated bituminous cement may be carried out either by applying the bituminous cement in heated form by means of a pressure distributor upon the dry aggregate after it has been placed upon the foundation, or by mixing the bituminous cement and the aggregate, at a suitable high temperature, in an asphalt mixing plant of any of the well known types and transporting the coated aggregate to the site of the building operation. In either case, it is of course perferable that the loss of heat be reduced as far as possible, that is, that reheating of the materials be avoided so far as possible. While the road building apparatus herein described is capable of heating the coated aggregate sufiiciently to render it workable, it is preferable, if the aggregate be coated in place on the foundation, that it be mixed and worked into a completed pavement before cooling and, if the aggregate is pre-coated in a mixing plant, that it be transported with as little heat loss as possible and that it be mixed and worked immediately after being deposited on the foundation.

A road building machine for carrying out this simultaneous heating and mixing also has high utility when used to spread and finish many of the so-called cold mixes, that is, mixtures of aggregates and bitumen which set up from other causes than the loss of heat. Such mixes can be worked and finished much easier and faster while warm than when cold. The machine keeps the material warm during the finishing period, and thus produces a better result in less time and at taken on line 55 of Fig. 2, and showing the circulation system of the medium for heating the various parts;

Fig. 6 is a view in perspective of one of the parts shown in Figs. 1, 2, 4 and 5;

Fig. '7 is an enlarged view in vertical transverse section, taken on line of Fig. 5;

. Fig. 8 is agreatly enlarged fragmentary view in vertical transverse section, taken on line 8-8 of Fig. 5;

Fig. 9 is agreatly enlarged fragmentary view in vertical longitudinal section, taken on line 99 of Fig.- 5; V

,Fig. 10 is an enlarged View in horizontal section, showing in plan the means for holding one of the parts in adjusted position; and Figs. 11 and 12 are, respectively, a View in side elevation and a plan view of a modified structure embodying the invention.

The structures shown consist primarily of a sled ll, provided with front wheels [2 and rear wheels l3 adjustable relative to the sled to vary its height relative to the road foundation. The sled comprises I-beam side frame members l4, secured together at their rear ends by cross members I5 and I6 and carrying, spaced somewhat from the rear end, an I-beam cross member I! that is secured,.by welding. or similar means, upon the. top of the side frame members, as shown best in Fig. 4. Other cross members l8, l9 and 20, preferably of Ll-shape, are suitably connected at their ends to the webs of the side frame members, to form with them a rigid framework, as shown in Fig. 5. To the top of the side frame members there is secured a cover plate or housing consisting of. a flat topportion 2| and downwardly extending side portions 22 spaced laterally from, and parallel with, the side frame members, as shown best in Figs. 5 and 7. This cover plate is preferably formed with spaced walls of heavy sheet metal and filledwith asbestos, or other suitable heat-insulating material, one of the chief purposes of such .coverplate being to retain the heat in the aggregate While it is being mixed, as the machine is being moved over the aggregate.

Heated agitating blades are rigidly secured to the side portions 22, the side frame members l4 and the cross frame members I8, [9 and 20, as shown best in Fig. 5, being arranged and inclined so as to, force the aggregate projecting above the lower edges of the blades in reverse directions laterally of the frame. In the embodiment shown three pairs of

blades

23, 24 and 25 are used, the leading blades 23 and the rearmost blades 25 being'arranged to deflect the aggregate toward the center line of the frame, while the intermediate blades 24 meet at the center line and are so inclined as to deflect the aggregate toward the side portions 22. It will be understood that the number, arrangementand inclination of the blades may be .variedas. desired. The outer ends of blades 23 are adjustably securedto the depending side walls 22, as best shown in Fig. 8, the blades each having a bolt 21 extending upwardly therefrom through a lug 28 Welded to the side portion 22 and provided with nuts 29 on opposite sides of the lug. The inner end of each of the blades 23 is secured to a lug 30 rigidly connected to the cross member 20 and connected by a diagonally extendingbrace 3| to the lower side of the respective side frame member l4. Aside from this vertically adjustable support of the outer ends of the blades 23, all of the blades are preferably rigidly connected to the frame. The blades 24 are secured adjacent their inner and outer ends, respectively, preferably by welding, to the cross frame member I9 and to the side frame members l4. The rear blades are similarly secured to the side members 22, side frame members [4 and the cross frame member l8 Each of the

blades

23, 24 and 25 is hollow, for a purpose which will later appear, and is preferably rounded on the lower rear corner, as best shown in Fig. 7, and each blade is preferably provided with a wear plate 32 secured by rivets to the front face of the blade at its lower edge.

A hollow strike-off blade or screed 33 is mounted for reciprocation transversely of the frame, to the rear of the rear blades 25. As best illustrated in Fig. 4, the screed 33 is formed with pairs of upwardly-extending arms 34 rigidly secured thereto and preferably reinforced by diagonal braces 35 welded to screed and to the arms. Each pair of arms 34 carries a flanged roller 36 engaging the top surface of the I-beam cross member l1, and a flanged roller 31 engaging the bottom surface of such beam, and one pair of the arms 34 is pivotally connected to a pitman 38 by which the screed may be reciprocated. Two angle iron cross members 33 and 4B are provided to guide the screed 33, the side frame members [4 being cut away to receive such angle iron members which are welded to the side frame members, the lower flange of the lower angle iron member 40 being engaged by the front face of the screed 33, as shown in Fig. 9. A pair of rollers 4| carried by brackets 42 welded to the bottom faces of the side frame members I4, engage the rear face of the screed 33. A wear plate 43 is preferably provided on the bottom face of the hollow screed 33, being preferably welded thereto, and the front edge of the wear plate 42 is preferably scalloped and beveled, as shown in Figs. 6 and 9.

A hollow finishing blade or smoother 44 is rigidly, but adjustably, mounted on the cross member IE5 at the rear ends of the side frame members 14, as shown in Figs. 2 and 9, having rigid vertically extending angle-iron arms 45 that are slidably engaged between the cross frame member l5 and guide members 46 that extend about the angle-iron members45 and are secured at their forward ends to the webs of the side frame members I4. The tops of the angle-iron members 44 are provided with threaded extensions 41 passing through lugs 48 extending rearwardly from the cross frame member 15, and nuts 49 on the extensions 46 serve to adjust the blade 43 vertically and tion.

Vertical collecting plates 50 are provided at the respective ends of the angle-

iron members

39 and 40 which guide the strike-off blade or screed 33, being welded, or otherwise rigidly secured, to the ends of such members and extendhold it in adjusted posiitcanloe manually removed and placed in advance of the mixing blades 23.

The rear wheels I3 are preferably dual, as shown, each pair being carried by a stub shaft 5| mounted in one end of a bell-crank 52 on a shaft 53 that is pivotally mounted in bearings 54 sunk into, and secured to, the side frame member I4, the other ends of the bell cranks 52 being provided with tension springs 55 adjustably connected at 56 to the body of the machine and normally tending to move the wheels downwardly, and hence raise the rear end of the frame. A worm gear 51, mounted on a bracket 58, is provided to control the rotation of the shaft 53, and hence the adjustment of the rear end of the frame, and is provided with a flexible shaft 59 extending to a gear box 60.

For carrying the front wheels I2, a framework comprising two longitudinal members 6| is pivoted to lugs 02 that extend upwardly from the cover plate portion 2|, and are preferably welded to the side frame members I4 and extend through the cover plate member. The members 6| converge toward their forward ends where they are secured to the top of a column 03. Vertical frame members E54 are also secured to the top of the column 03 and carry near their upper ends the gear box 60. Bracing members 65 are secured to the upper ends of the members 54 and, at their rear ends, to the longitudinal members 5|, and a flat cross member 06 is secured to the top of members 6| and carries a shaft Bl having bellcrank levers 68 secured thereto and a worm gear device 59 for controlling the position of said bellcrank levers and operated by a flexible shaft I extending to the gear box 60. Tension springs II are adjustably anchored on the body of the machine and are connected to the upwardlyextending arms of the bell-crank levers 08, and the forwardly-extending arms of such levers are connected by chains I2 to a plate I3 that is secured to the front ends of the side frame members l4 and the front edge of cover plate portion 2 I. The column 03 is hollow and receives a king pin extending upwardly from the center of the front axis I0, on which the front wheels I2 are pivoted, and any suitable members I5 are secured to the axle I4 by which the device as a whole may be drawn along over the road foundation. The gear box 60 is provided with a hand wheel I0 and suitable gearing, andselective engaging mechanism therefor, by which the wheel l6 may be connected to rotate either flexible shaft 50 or. flexible. shaft I0, as desired, to raise or lower either the rear or front end of the machine as a whole.

As stated heretofore, the agitating

blades

23, 26 and 25, as well as the strike-off blade or screed 33 and the finishing blade 44, are hollow, and suitable means for circulating a heating liquid therethrough is provided, as best shown in Fig. 5. Such heating system includes a reservoir 'I'I secured in place in the top surface of the cover portion 2|, and on top of which there is mounted a force pump 18 which draws the heating medium from the bottom of the reservoir and discharges it into the inner end of one of the blades 25. The system also includes pipes I9 secured to, and in close engagement with, the depending side members 22 of the cover 2|, so as to transfer heat thereto, and a flat grill 80 formed of reversely bent piping, and adapted to be heated by burners 8| which, as shown in Fig. 7, are directed downwardly and inwardly through the side walls 82 of a burner cover plate'83 mounted to cover an opening 84 at the forward end of cover member 2|. The burners 8| may be of any suitable construction, and are fed by piping 85 from -a fuel tank 86.

' The various units of the heating system are connected together by pieces 81 of flexible tubing formed of rubber, or other suitable material, and as a heating medium any suitable fluid may be used that is liquid at ordinary temperatures and has a boiling point in excess of 600 F., such as heavy lubricating oils, or residual oil from the distillation of petroleum bases to an end point of approximately 600 F. From the pump I8 the heating liquid is circulated through left blade 25, left blade 24, left blade 23, the coils of the grill 80 where it is heated, left pipe I9, finishing blade 44, strike-off blade 33, right pipe 79, right blade 23, right blade 24, right blade 25, back to reservoir Ti and to the pump, and it is preferably maintained at a temperature between 500 F. and 600 F.

A suitable engine 88 is mounted on the cover portion 2|, for directly driving the pump I8 and for reciprocating the strike-off blade 33 through a chain drive 89 from a small gear on its shaft to a larger gear 90 on a shaft 9| having a clutch connection to alined shaft 92 which is provided with a crank arm 93 to which the pitman 38 is connected. A short distance to the rear of, and in line with, the throat formed between the rear ends of the converged rear blades 25 a distributor vane 94 is provided, extending rearwardly from a vertical shaft 95 having a handwheel 96, by which it may be swung, and with a notched wheel 9'1, adjacent the top surface of the cover member 2|, and a cooperating locking dog 90, as shown in Fig. 10, by which the vane 90 may be held in various adjusted positions. It will be apparent that, by varying the angle of adjustment of the vane 94, the proportion of material directed to the right-hand end and the left-hand end of the strike-off blade 33 may be varied.

In general, the structure shown in Figs. 11 and 12 is the same as that shown in Figs. 1 to 10, but modified by having a power plant mounted for driving the rear wheels, by providing modified means for adjusting the rear wheels vertically, and by providing a tiltable batch-receiving hopper on the front axle, with suitably modified means for directing the front wheels. As shown, an engine 99 is mounted on the machine frame, having a hollow axle I00 pivotally mounted on the side frame members at IOI and provided with rigid forwardly-extending arms I02 carrying the stub shafts upon which the driving wheels I03 are mounted. A worm-gear device I04 is connected to the forward end of each arm I02 and driven, through a vertical shaft I05 and bevel gears I06, by an elevating wheel I0I.

The front axle I08 is carried by forward extensions I09 of the side frame members I4 and by braces IIO extending forwardly from the side cover portions 22, and the front wheels III are pivoted to the ends of the axle I00, as in the usual automobile construction, being connected together by cross connecting rod II2 for movement in unison and connected by drag link 3 and suitable mechanism to a steering wheel II I near the rear of the machine. The hopper I I5 is provided with downwardly-extending lugs IIG by which it is pivotally mounted upon the axle I08, and has a fiat front scoop portion I I1, formed to lie flat on the road foundation, and an inclined portion II8 extending back and upwardly over the axle, so as to dump its load between the axle I08 and the front end of the blades 23.

The machines are shown in Figs. 2 and 11 as they rest upon a completed road. It will be understood that, when the machine is in use, the front wheels will travel on a surface lower, by the thickness of the paving being applied, than the level of the completed road surface, while the lower surface of the strike-off blade 33 determines the level of the completed surface and the finishing blade 44 should be adjusted so as to rest upon such surface. The lower edges of the front agitating blades 23 normally are located, in use, slightly below the lower edges of the blades 24, and the blades 24 are, in turn, slightly lower than the rear blades 25, the lower edges of the rear ends of the latter blades 25 being only slightly below the level of the bottom of the strike-off blade 33.

As either of the structures shown is moved over the road foundation, it will be understood that the coated aggregate will be heated not only by the direct action of the burners 8| but also by contact with the

blades

23, 24 and 25, the striking-off blade 33, the smoothingblade 44 and the depending side cover portions 22, While the cover member 2|, 22 as a whole serves to retain the heat and the hot gases from the burners. At the same time, the effect of the

blades

23, 24 and 25 will be to thoroughly mix the coated aggregate as the blades 23 converge it toward the center line, the blades 24 spread it out toward the side cover portions 22, and the blades 25 again converge it toward the centrally located throat between their rear ends where it is engaged by the vane 94 by which its distribution to right and left is varied. I The reciprocating strike-off bar levels off the thoroughly heated aggregate, while maintaining its temperature, and any surplus collecting adjacent the plates 50 may be readily removed and placed in front of the machine. Finally, the finishing blade or smoother 44 will remove inequalities and tend to catch any stray pieces of aggregate.

It will be understood that it is preferable that the road be rolled immediately after the aggregate has been mixed, formed and leveled by the road building machine herein described, and that as the aggregate cools to atmospheric temperature it sets up to form a wearing surface having a high degree of stability, without pores and practically impervious to water, so that the road may be used at'once without the delay entailed by waiting for a set up by' evaporation of the light volatiles which is necessitated when the aggregate is rendered workable by the addition to the asphalt of naphtha or other out backs.

What I claim is:

l. A machine for spreading'road material, comtherein, a portion of said circulating system being associated with said blades and said screed to transfer heat thereto and a substantially flat heat-retaining plate covering all of said agitating blades.

2. A machine for spreading road material, comprising a cover plate having depending side walls, hollow, laterally-inclined blades beneath said plate and carried thereby, a hollow screed extending transversely of said plate, a fluid circulating system including said hollow plates and screed and having a portion associated with said side walls, and means associated with a portion of said circulating system for heating the fluid therein.

3. A machine for spreading road material, comprising a frame, agitating blades rigid with and depending from said frame, a screed carried by said frame, a cover plate above said blades, a fluid circulating system associated with said blades and screed to transfer heat thereto, and means associated with a portion of said circulating system beneath said cover plate for heating the fluid therein and for heating the material before it is engaged by said blades.

4. A machine for spreading road material, comprising a cover plate having depending side walls, blades rigidly carried by said cover plate and laterally inclined to direct the road material toward and from said side walls, a transverselyextending screed spaced rearwardly from said blades, a fluid-circulating system associated with said blades and screed to heat them, and means associated with a portion of said circulating system for heating the fluid therein.

5. A machine for spreading road material, comprising a cover plate having depending side walls, blades rigid with said cover plate and laterally inclined to direct the road material to and from said side walls, a transversely-extending screed rearwardly from said blades, a fluid-circulating system associated with said blades and screed to transfer heat thereto, means associated with a portion of said circulating system for heating the fluid therein, means for circulating the fluid through said system, and means for imparting reciprocatory movement to said screed transversely of said cover plate.

SAM E. FINLEY.