CA1150992A - Method and apparatus for repairing longitudinal seams or cracks in road surfaces - Google Patents

Abstract

T I T L E : Method and apparatus for repairing longitudinal seams or cracks in road surfaces A B S T R A C T

The invention relates to a method for repairing ruptured longitudinal seams or cracks in road surfaces which consist of a thermoplastic material and particularly of an asphalt coating including bitumen and mineral constituents, by which, under the application of heat, new coating material is applied and consolidated in the area of the longitudinal seams or cracks, wherein at first mud and humidity is removed from, and out of, said langitudinal seam or crack, said longitudinal seam is subsequently softened by heating, said softened coating is loosened from the underground and is compounded with the new material and/or liquid or liquified aggregates and is finally incorporated and consolidated again.

The invention relates also to an apparatus for performing the method, comprising a chassis including an own drive engine and at least one heating device and means for lossening the road coating arranged behind it as seen in the direction of motion, wherein as the means for loosening said road coating a small roller provided with chisels and rotating in a direction opposite to the direction of motion is provided, which roller is arranged in the discharge area of a container holding said new coating material such that when rotating said roller in the discharge area of said container, compounding the old coating material transported up by said chisels and of the new coating material is accomplished.

Description

METHDD A~D APPARATUS F0R REPAIRING LQNGITUDINAL
SEAMS or~ CRACKS IN ROAD SURFA OES

The inventlon relates to a method for repriring ruptured lc,ngi-tudinal seams or cracks in road suriaces whieh eonsist of a thermoplastie material and particularly of an asphalt eoating ineluding bitumen and mineral constituents by which, under the applieation of heat, new eoating material is applied and eonsolidated in the area Or the longitudinal seams or eracks.
Partieularly in the case oi' roads having several lanes, the longi-tudinal seams between two adjaeent laules, eaused by the influenee ofthe weather and/or oi' a heavy trafi'ie, may rupture and thus admit, through these eraeks, water and humidity into the road eoundation, whieh migrht lead to a progressive destruetion ol' the r~ad sull'aee partieularly durin~r tl~ cold season In the asphalt s~ut'aces, to,o, lon~ritudinal erack~ ~ly form beca~se Oe heavy tral'L'ic ~)y which a simila-r prematule wear and d~wKe ot' the road is prc~)t~l.
Ii' and when such -rlJI)tur~d lon~ltudLnal se~l~ or lollgLtudinal cracks were repaired at all, tl~is was done by l`llllng them with ~ preheatc-~l i'iller material or in cuse of broa(ier eracks or fiss~res by applying new heated eoating rnaterial, whieh wus subsequently consolidate~l witl -the aid of a hand-operated roller. This way ol' repairing rupt~ured seams and eraclss in the road surface, however, leaves mueh to be desired as coneerns the stability as well as coneerns the suri'ace quality of' a road surf'aee so repaired.
In order to repair road surfaces damaged by the influence of the .. : . ..

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weather and/or by heavy traffic, rnethods have been known wherein as a first step the mad surface is milled off or peeled off and a:fter the removal of the milled-off or peeled-off material a new coating is rlp~
plied. During the course of the miLllng off or of the peeling off as well as in the course of the application of the new coating, the road surface is generally subjected to a heating by which the milling or peeling is simplified and a be-tter adhesion of the new coating to the underground is obtained. The milled-off or peeled~off rnaterial is eithe.r transported by trucks to dumping sites or, according to a newer method, is ccmpound~
with the new coating material in a relation corresponding to the require-rnents and this compound is applied onto the milled-off or peeled-o1`e roaci surface. To this end, the millecl-off or peeled-off material is transported by highly sophisticated conveyor means to a container, which is also charged with the new coatin~r, material erc~1 a truck.
Par-ticularly in the last-describ~Y1 pr-ior art methc)d, the repair costs per m~ (mi-t may consi(lerably be redl1ce(i as cant)~red to any ot;het method. This mett1(xl, howeve1, Ls not suiLed eor reE)airint,r lon~ritudit1aL
cracks or I~lptured lont~ritu(ii11ll s~ams oL/ roui ~s~1rt'u es consider1nLr ttr~t.
-the 1~se oL~ machinety L'or the re~ir Or only stna11et ~(~1S, which :Lon~i-tudinal se"n~s an(i cr1~ s~~te, would L)e~tnuc11 too co~t1y Uld the re~plir eosts per unit oL' r~ad sur~ace wou:Ld be too excessive.
It is, thereeore, the aim o~' the invention to provide 1 method by which the repair Oe ruptured lonL,ritudinal sean~ or lon~r,itudinal crac~s in the sur~'ace coatingrs is possible with minimum technical and personal costs. 'Ihe method should moreover so be conceived that it permits the z pe~nanent closure of seams and cracks.
In accordance with the invention, this problem is solved by a method wherein as a first step mud and humidity is removed f'rcm, and out of, the longitudinal seam or crack, the longitudinal seam is subsequently softened by heating, the softened coating is loosened frc~? the underground and is compounded with the new material and/or liquid or liquified ag-gregates and is finally incorporated and consolidated again.
By agr~regates, minerals such as -for instance bitumen, so-called i'lux oils, light i'uels and the like are to be understood, which are suited to improve -the quality of the material to be incorpora-ted and to increase the adhesion between the individual p'~ ticles.
This method, i.e., cleaning, heating, tearing, incorporating tl~
new coating rnaterial and/or aggregates and consolidating, permits a permanent repair of longitudinal, rupture~d seams or crack~ ln a srnal'L
neighborhood thereof, which rneans that the repair works may not on'Ly be performed rapidly and wi-th little new coatill~rrnaterinl but a'lso, witl a view to the limitation of' the work.s to a very ~qnall area, m~y be In.lLle without subs-t~mtially impa:iringr th~ trarf'ic t'l~w. Tho Lalter ~nstitlltcs a particular advantu~e ol` tlle n~tll(xl accl)I(Iing to tlle invention consi(l(l-ingr thaL; no c~)stly street barlicades ne~l be e~ecLe(l an(l no time and lut!`consumin~ detours have t;o be n~lde~.
Partlclllarly the prior cleaning Oe the cracks ~nd longitudinal se.uns down to -their base fl~m mud and h~midity and the incorporation Oe the ne~w material in-to the road coating loosened erom the underground and soetened, result in a good ccn?pounding oi' the new and the old coatings and the longi-~S~ 5'~

tudinal crac~s are closed permanently and resistent to major loads bytlle flowing traffic.
In order-to obtain a high cleaning degree in the longitudinal cracks, or longitwdinal seams, respectively, which is of decisive im portance for a lasting repair, the longitudinal seam or the longitudinal crack, respectively, is most suitably treated with a burning ~ras-air mixture of high flow velocity. I-t is advisable in this case to allow the gas-air mixture to pass into the seam, or the crack, respectively, at an oblique angle as otherwise the rnud and dust, which is whirled up, is not ccmpletely blown ou-t Or the seam, or the crack, respec-tively.
It has furtheron shown to be suitable that the sottened coatin~ is loosened not only fran the underground but also in itself`, which means that the coating should more or less be crumbled so that the new co.lt:ir ~ material may more easily be applied. It is of p.~rticullLr advantage ir during and a:~ter the addit:ion of the new coatin~r material the so~telle(l and l.oosened coatin~r is 1nti.mate:ly blended for a lo~r time with tlle n~v coatingr material. lt h~s shown thut the de~ree Or blendill~ wi.ll exe:tt an increased ineluence on the dutabil.iLy ol' the repuir, tllat ls, witl the ~rovJln~ blendi.n6r debrree the .llrt of' the coute~l are.l retr.lilecl w:i.ll : ~o i.ncreuse.
In accordatlce wl.th ~n advatltu~-Y~u~ ~ml.x)dilllent oL the invention, tho c~mpound o~ old coatin~ n~aterial and Or ne~w coat:ing materi.al is su~),jectetl to a iurther heatirl~ process p:rior to consolidation. This step shou:lcl l)e ~n~loyed particularly in such cases ~hen old and new coating materials are heavily blended as in this case both materials will cool down relatively ~5~Z

rapidly. The consequence is that particularly in the area of the seam or crack bottom the cornpounding of the blended coating material with the road sur~ace foundation might be too poor. The latter is particu-larly the case when dealing with relatively deep seams or cracks.
For the same reason, i.e., aiming at an intLmate catnpounding of the blended coating material in the bottom area Orc the seam or of the crack, it is advisable to subject the coating cornpound to preconsolidation prior and/or at`ter the heating process.
In order to improve adhesion , it has ~urtheron shown to be advanta-geous to spray the road surface so treated prior to the incorporation ot`
the material with a liquid or liquiiied aggregate.
A further idea of the invention relates to an apparatus tor pelf ing the method according to the invention. This appaIatus canpr:ise~ a prior art ch~sis including an own drive engine and wheels and/or ctlter-pillar -tracks and including at least one heatinbr device and means E`o[
loosening the road cotting arranged behincl it .~s see~n in the clirection ot`
motlon.
~ IC`. apparatu~s accordin6r to the inverltion dLI'eet~ frc~m the priol 11't devices in that as the m~u~s l'ol l(x~ellin6r the road coatLn~, a .sn~ . tol.-ler provided witll chisel~ and rotatlng in 1 dLI~ction opl~x:ite to thedirection o~' motion is ~ )vided~ which roller is arrwlged in the di~charge area o~ a colltainer hold:Ln~ the n~ coatin~ tnaterial such that when rotLlting the roller in the discharge area o~` the container, ccmpoundinbJ o~ the old coating rnaterial transported up by the chisels and of the new coating tr~telia:L
is accc~plislled.

~ e roller provided with the chisels fuliills two functions; it loosens the road surface in the area of the seam or the crack, and the coating in itself, and on the other hand blends the old, loosened coating with the new coating material. Special devices for blending the new and the old coating materials or devices for transporting-the olcl coating material to such a blending device are, therefore, no longer necessary in the apparatus according to the invention. This is a particu- -lar advanta~re Or-the apparatus according to the present invention. In accordance with -the invention, a container including a doeing device eor liquid or liqui.eied aggregates is provided.
In accordance with an advantageous em~31unent o~ tlle present inven-tion, the doeing device opens in the discharge area ot the conta.iner receiving the new coatin~r material. In this way, the a~regates ~each the correct location in order -to be intimately belended w.ith the o:ld u in given cuses, new co.tin6 muterial.
In acco:rdance W.Ltll a ~urther e~x3dimellt ot` t}l~ Ul)l)aratUS aCCOl(l:in~
to the invent;:i.on, the d(~:LIl~ devl(:e .is additiollully COlllleCted (ir nt,`Ce~S;.ll'y) to u eprayer dev.ice coveri.ll6 the whole w:i.dtll Oe tlle lu~3tllre(l SUL'i'UCe to t3e treat~(l. 'l`h:Ls e~3r.uyer devi.c~3 sprays the a~re~ute(s), i.e., ln lllis

2() c~se the u(illesioll improvill~ sut)stall-:es, into the ~up Lrall whicll the ol.(l r(),~l (~)ating rl~ter-i.al. hae beerl tuken so that the ne~wly i.ncorporated matel:i.ul.
will sllbstalltial.ly betteI aclht3re to the resi.dual coating.
~ 3ns:iderin6 th~t the added ag~rle~,rutes muy ulso include such ag~:re~utes, which under no~mal conditions are solid, the container ~or the liquid or liquieied agrgreKates is provided, in accordance with a par-ticularly advun-ta~eous g'~

embodiment of -the apparatus accsrding to the present invention, with a corresponding heating device. This heating device may either serve for liquifying the added aggregates or only to maintain the liquicl state if they were already added in that state into the container.
-5 In a particularly advantageous e~bodiment of the apparatus of the invention, the container for the aggregate(s) is wholly or partly pro-vided with a metal sheet mantle througrh which the combustion gases of the drive engine are conducted.
For dosing the aggregates, any devices comnon to those verse(l in the art may be employed. It has, however, shown -to be particularly ad-vantagreous if the anK)unt of the liquid or liquified aggregrates added by the dosing clevice is controlled depending on the moving sI)eed Oe the apparatus. In this way, it is safegualded that equul c~no-mts Oe the ag-gregrates are added per unit of length of tlle longitudinLIl seam repaite(l so that a thinning of the newly :incorporated roacl sureace coating or , thickening thereof is avoided.
In ac~ordanc~ with an aclvLultL~reo~ls ~ x)dill~?nl; of til~ VelltiOII, tlle contu:iner i'or tlle llew cx)atillg mal;erica'l pL~SeS, at the l(~wer si.de thel~ol', over into a tub~ r e~Yten~ion ol' rocl:Lmgular (:row sectioll, :Ln whlcll the rolleI c~lrryill~ the clllsels Ls rotatL~l)ly slJpIx)rt~l. 'I`he arrLm~nc~ t or the ro'llel calryin~ el~ in the l~el portion ot' the containel hLIs the ~dvantL~e thLIt a particul~rly intimate blendLIl~ between the olcl coating materiLIl and the new coating mateLiaI is obtclinecl.
l~le blending degree may furtheron be increased in that the chisels are arraulged in at least three levels spaced r-elative to each otheI and perpendicular to the roller axis the chisels in one level being stag-gered relative to those in the adjacent level in the circurneerential direction oi the roller. By so staggering the chisels, the old and the new coating material is not only moved to and fro in the circurnferential direction of the roller but also in the longitudinal direction of the roller, which has an advantag~eous effect on the blending of the two n~terials. When employing a roller having three chisel levels, i-t ha~s proved to t~3 suitable to stag~er the chisels oi' one level relative t;o those Oe the adjacent level at about 120 as it has Sllc~ tllat in this case a particularly good blending o~ old and new materials may be ob-tained.
Control ol the discharged amount of new and old coating material is su.itably obtained in that the rear wall of the tubular c~)ntainer ex-tension is heiKht Lu~justable. By raising, or l~erin~, repectively, of the waLl, the amount to be dischul~ed n~ly be increased or decreastYI in the desired manner. For the heiKht; ud~justlnent o~ the wull, a screwed spindle is suitably provid~d ~lichlnay be s1lp~x>rted at tt~3 contuiner wa:l1.
In order to obtain L~l even dischurue o~ tlle blende(l c~)uting mat~-3r:ial i'rorn the l;ubulur extensioll ut the r~lr wùll, it is advlsab1e t;o pr~)vi~e tht-3 latter at ttn~ oute1~ side tllerc~l' witll an extensioll simLILl1 to a finishillg scree(l. By using th~ finishir~ sc1eed like extensi0n, a ce1l;uir consoliclation o~ the blended mater.Lal in itsel~ an(l in the seLlm, or the crack, respectively, is udditional]y obtuined. This p-reconsoLidatioll may moreover be eavored in thut at least the lower area of the rear wall ~nd, ~5 i-e necessary, the screed-like extension is in operative connec,tion with a

3~2 g heatin~ device. The wall and the screed-like extension pass on the heat fed to them to the blended material, which, therefore, fits part:icu-larly well into the crack or the seam down to the crack bottan or -the seam bottan, and because of the increased plasticity caused by the heat fill snug into smaller recesses as well.
In order to adjus-t the loosening depth of the coating to be repaired, the container carrying the chisel roller is height adjustable. This height ad,justment may in accordance with an en~odiment Oe the invention be obtained in that the wheel pair of the eha~ssis adjaeent the containel is height adjustab]y secured to the chassis. In aecordance with another embodiment it may also be the cl)ntainer, which is hei~rht adjllstably secured to -the chassis, a solution whicll is to be pret'erred over the otller one as it is aceanplished with less costs~ As for the rest, it c.ulllot be exeluded that in special c:ases the whe~31 p~ir of the ch~sis adjacent tlle ; 15 container as well as the container are ht3l~r,llt adjustably securtci to the chassis thus pennittin~ u coarse ~tJustr~nt via the height adjllstable whec~:L
pair and a fine a(~justmc-~nt via the h~ight ad,j-lstment l~?lwe~-3n contuiner an(l chassis. In such u ease, the lle~i~rllt; ad~justu~'le whe~l p~lir s(3tves a'lso l;o llold the contailler Witll tt~? ctlisel rollel clurirlLr, pure tluvellin~ ol)erlLion~
i.e~, when it truvels erc~n one pla((3 ot' opcratioll to tllt~ other, in Ul t)pe:rable pOS:itiOII el~vated ~er~n the road sutl'uce.
'l'he~:Lattel~ may also be achieve(t in accordunce wi-th another en~x)di~ rlt ot' the invention in that the container witll tl~ chisel ro'Ller is swlve'llin~-ly secured to the chassis around an .~is parallel to the roller ~iS~ ~[n such a case, a height adjustable wheel pair may be dispensed with unless it is required for the exclusive height adjustment of the container or the adjustmc?nt of the loosening depth, respectlvely. In a particularly preferred en~odiment, the container is secured to a holder having a-t leas-t one lever which holder on its part is untwistably secured relative to a shaft rotatably supported on the chassis. The shaft earrying the holder is suitably substituted by a roller as in that case, because of tht? sub-stantially higher weight of the roller as ccmpared to a shaft, vibrations and oscillations as will occur during the course of the operation ol` the chisel roller have a s-ubstantial smaller effect on the whole apparatus, the loosenin~r depth and the evenness of the seam or craek repair.
For swivellinK the holder with the container, there is most suitab]y provided on the cha~ssis a preferably pneumatic or hydraulic positionin~
device the moving el~nent of which is in operative connection with -the lever.
In order to get the apparutus t)y a mini~num of' switchillg maneuvels, and thus as rapldly L~ ~)ssiblt3, into the~i~x)sition necessary t'or t;ht3 I~C~-pair of' a longitudinal SeLUn or a lon~ltudin~L craek, t:he contLIiner to~e~ e with the ehisel rollt,~r is most suitu~ly Cl'OSS ad~justul)ly arrarl~recl on the chassis. The uppurutus nt?ed tht3rl on'ly l~ I)rou~ht lnto u ~)sitlon pLuu'll(YJ
to the lon~rLtudinal sewn to t~e repLIir~-~ or to ~ht,~ lon~itudLrluL c:rLIck Lo ho rep~ired rather thull into a position exwctLy alx)vt3 the seurn or the crack, respeetively, whiceh would entaiL sul)*tantial'ly more maneuvering. r~he ex~,t adJustrnent oE tt~-3 loller, which carries tht,~ chisel, and o~` the oontuirler is then obtained by cross ad;justment thereot' relative to -the chassis oe the apparatus, z For the cross adjus-tment Oe the container with the chisel roller relative to the chassis, there is most suitably provlded a closed pris-matic guide, one portion of which is secured to the container while the other portion thereof is securecl to the chassis. The adjustment is ad-vantagreously made with the aid of a raek-and-pinion gear where the raek is connected to the container and the pinion engagring with the rack is arranged Oll a shaft provided with a crank.
In order to ob-tain an even loosening depth over the whole roller length relative to the road eoating surface, tllere is provided in accolci~ce with an advanta~reou~s embodiment, on the two side walls o:t` the tubular container extension one skid each on which the container glides on the rotd surfclee during the loosening opera-tion. For th~ same reason .it i.s advisable to provide bocms on the container arranged transverse to the direction oc motion to the end Oe whieh b(~ms heigllt a~l,jnstal)le skids Ul'e secured. For the height ad~ustn~nt Oe the skids, scIew~Yi spind:l.es m~y be provided, which are arranged in cor:respc)ll(iing thlel~e(i l~ushi.ngs ~uld t;he free ends O~e which are provide(l with u el~ulk eacll.
In aceordance wi.th a l)re:felle(i ~n~o~l:iment ol the illvontioll, a rirsL
heatill~ (lev.Lc~ .is l)t~vid~3~ ill tll~ )nt ~ ?~ w~lllt3 ~ ~!col~ tillg (l~vic~
is plovided bt3twee~ll th(3 two wheel. pal.ls oL tll~ chl~.is. l3y tllis J~ .n~3-metlt, a particllla~ly cc~llpa~t structule o~ the appalatus nray be ol~t:a:in~.
the helti.llg device, in.l`.ra-red r~diators ~ave shown to he su.itaL)Le whi.le otl~r electric or gas-operated lleatin~ cLevices may be ~nployed as well..
In i'rorlt of the fi.rst heating deviee, there are provicled, i.n accordanee with a further develo~nent ol the above rnentioned ernbod.iment, liquid g1S

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operat~t ~urners for removing n~ld and humidity Erorn the longitudinal seam to be repaired or the longitudinal crack to be repaired. In order to obtain an optuTum cleaning eLfect, at least two to three burner rows are arranged one behind the other in the direction of motion. The firs-t heating device and the burners are suitably ccmbined to constitute one structural unit, which is swivellingly secured to the chassis. This n~kes possible to swing up the heating device burner unit during travellin~
operation, i.e., when the apparatus is -transported from one location to another-, and thus render the apparatus better maneuverable than would be the case with the heating device - burners unit down.
In order to obtain a par-ticularly smooth and steady repair oL a ruptuled longitudinal seam or longitudinal crack, a third he~atin~ clevice is provided, in accordance with a ~urther development oE the invention, behind the container in the directi.on ot Inotion. By thix heatin~ device, the ccmpound consistin~r ol old and new coatin~,rll~t;eriul Iilled into the seam or tl~ crack and already ~r~econsoli(LateYI is l~.lte~ .~rain in tts sllr-Lace area slu)rtly prior Lo tlle rinuL coll~)lLclati<)n~ which lllay be n~(te by a cc~mon road ro].l~ K~ collxeclllen(e is that Ln ud(li~i(>ll to the at~)ve~
m~ntiolle(i adv~nta~es, tlle c~llxolidlltioll in t;he s~rruce~ U.l'(,'cl oL' lh~ (~aLir (~m~)und applie(l is pc~ ticulalLy xtroll~, which hu~q a t`avora~le el'l`e(t on the abra~ive resistance ot` tll-? roud surt`ace repair~d.
The heclt:in~ devi(~ is udvc~lt~ )uxly provided on ski(~ and is re~
m~vably coupled to the container. It mcly thus in a s:imple Wcly, for in-stcmce, if it is not needeYi in case o~ smclll crack or secun depths, be decoupled and suspended at a suitable location on the apparatus.

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The Invention will now be explained in m~re detail based on the drawing which ineludes, partly in a sehematic represen-tation, exempli-fied embodiments.
Figure 1 shows a lateral view of a complete apparatus aeeording to the invention.
; Figure 2 shows a lateral view of a container ineluding a ehisel roller oL` the apparatus aecording to Figrure 1.
Figure 3 shows another container including a chisel roller, which is height-adjustably seeured to a holder swivellingly p:r~vided on the chassis, and Figrure 4 sh~ws a rear view to the container of the apparatus ac-cording to Figrure 1.
The apparatu~s cc~prises a chassis l including a steeluble Lrollt whe~l pair 2 and a rear wheel pair 3 lleigllt ad~ju~tably secllred to chassis 1. ~etween the fron-t wheel puir 2 and the ~?ar- wh~el. pair 3, ther-e i..9 provi.clecl, on chassi.s :I, the dr:ive engrine 4, at the rear en(:l wh~?:r~?o:e th~ c~i.ver~'s sLlulcl 5 i~ lu(lill~r tll~ St~t`i.ll~r Wll~?I ~, ttlC? (Il`iV('l` S
seat 7 ~Id variou,s opelat:ion lev~-?ls 8 ure~c~rrangc~l~

[11 tlle ~'I`OIIt pc)rt:ion Ot' (~hcWSLS 1~ the~`e clt`e rOllr ~ gU~; ('011-tainers 9, onl.y tw~ ol' ~hk:h are ~h(~wll, k:)r f~eclillg u fitxt ll(?atLll~device :I0, a second heuting devic~e ll ~rrurlgred b~?tw(-~n wh~ .)ui.t~ 2 ~ul(l 3 and a. thil(llleatingr device 12, which is c~rrangr~i behilld ch~ss:is l~ Tl~e l.iquid ga~s Lr~:xn containers 9 operclt~Y f'urtheron a n~ber ot burneI~ 13, which are arranged in three rows one after the o-ther at the front end o:L
heatillg device 10. Burners 13 are provided in a holder 14 integral with 1'1 -heating eler~n-t lO to constitute a constructional unit 15. Cons~ruc-tion~l unit 15 is secured to an arm 16, which is hing~?d at its other end to chassis l. By means of a traction rope 17, which eng,~gres with the end of the arm 16 at the side o~ the constructional unit and is in connection via a g~uide pulley 18 with a worm gear secured to the chassis, constructional unit 15 may be drawn into a somewhat vertical position to enable pure travelling motion. On the other hand, the ground clear-ance of constructi.onal unit 15 rr~ay be adjusted by the traction rope 17 as well.
E3ehind the driver's stand 5, contaitIer l9 is provided, which, as can part.i.cularly be taken ~rom Figures 2 and 3, at the lower side theI~eot passes over into a tubular extension 20 of rectan~II.al~ Cl'OSS SeCtiOrl, ill which a device ~or loosening tlle roc~l sur.tace is arr,~mge(I.
Loosenlng device 21 comprises I~oIlt?r 22 (Fi6rure 3) on which ctIisc?:Ls 2~i are removlbly secured. ~.llen 22 is supported .in tt~? two side walLs 27 and 28 Oe ccnta:iner- 19. To ttIe sid(? wall 27 llOt sIx)wn, dl-iVe ellg.irle 29 for rol.l.~?~ 22 is secu~ . E~ e 29 (Ir:i.v~?s tIl~? IoI i~?l' illtO th(? tlil'(`('l;i(lrl ae arI~c~w A, i.t?., op~)si.te t.o tlle (lil~?(`t,.i.OII ot' ll~tiOtl Ol' ttIe apI)cllutlIs~
()n l;IIe side~ wa]l. 2~ oI coIIl;,lirle~ ,uI ~ukILLion.II (ont,Iinel~ ~3 Iot ~ o~ L~ rbrr~ Irtor~v~.~l pI~ovi~ r~ ontc~ 3 :is conrIect.ed, via dIlc~-t 2~, to d~in~r dev:ice 25, by whi.(~I de~fined cU1101111tS
Oe t;he ~gIegates may ~ c~Ided in the (tisch~rge arecl ot ~vntaine:r I.9.
As carl paI~ti.cul.arly 1~? taken fnan ~ res 2 cUl(t 4, I~ear wall 30 oL
tubul.ar extension 20 is ~eigrht adjustable by means ot a screwed sp.in(II.e 3:I.
Screwed spindle 31 engc~res w:ith its one end with a corresponding threaded ~ J Z

nut 32 secured to wall 30, and is supported with i-ts other end in a bushing 33. Bushing 33 as well as further bushing 34 is secured to the rear wall 35 of container 19.
The height adjustable wall 3~ of the tubular container extension 20 is provided at its lower end with a finishing screed 36. For heating this finishing screed 36 and the rear wall 30, three burners 37, 38 and 39 are provided, which are arranged in a holder 40, which on its part is secured between the two side walls 27 and 29 of the tubular exten-sion 20. The connecting pipes for the burners 37, 38 and 39 are not shown for the sake oi' clarity of the representation.

To the tw~ side walls 27 and 28 of the tubular extension 20, tWD boans 41 and 42 are furtheron secured to the rree ends oi' which one skid 43, or 44, respectively, each is height adjustably secured. ~br height adjusting skids 43 and 44, each o~ the tw~ skids is connected to a screw spindle 45, or 46, respectively, includinL a correspondinL

threaded nut 47, or 48, 49, or 50, respectively, each at the Lree ends thereof. Two further skids 51 and 52 ara provided inmediately at the ends of walls 27 and 28 adJacent the road surface. For the sake of clarity, the bo~ns 41 and 42 wl~tl th~ ~kids 43 and 44 ~re not shown 2() in ~'ig. 3-Container 1~ includin~r loosening device 21 :is provided, as can be taken i'l~m Fl~rs. 2 ~md 4, via a holder 53 on chassi~ older 53 comprises a rc~ller 55, which is supported in two side wal:ls 54, to the periphery of which holder 56 is screw~d. Holder 56 includes a guide ~5 57 constituting together with a guide body 58 a prismatic guide 59, 9'~

by which container 19 including loosening device 21 rnay be shi~t~i at a right angle relative to chassis 1. Adjustment is brought about by mcans of a rack-and-pinion gear 60 the rack 61 of which is rigidly secured tC? container 19 while the pinion of which is indirectly or directlyconnected to a crank 62.
Holder 56 includes furtheron a lever 62 which engages with the rnovable portion 63 of a pneurnatic operating cylinder 64 provided on chassis 1. By operating this operating cylinder 64 container 19 including loosening device 21 rnay be lowered around axis 65 frorn an elevated rest position into an operating position and elevated there-frarn again.
As already rnentioned adjustrnent of the loosening depth is achi.eved in accordance with Figs. 1 2 and 4 via height adjustable rear wheel pair 3. For the height adjustrnent of the tw~ rear wheels 3 two rack-and-pinion gears 66 each are provided operated by means oE crank 67.
The inclination oE c~ntainer 19 in the direction oE motion observed in case oE ~reatèr height adjustrnents is re~ulated by correspondingly actuating hydraulic cylinder 6~. In th.is way it is safebuardecl th~t skids 52 rest on the roaci surEace over the whole J.en~th thereof wh:l.le the rear wheel pair 3 may be in any hei~tlt position.
In I~i~re 2 the heating device provided Eor contalner 23 i9 nl~t shown :Eor the sake o~ clarity. ltlis heatin~ device may c~mpri~e correspondingly arr~n~ed gas burners which act upon the outer wall oi container 23. Other heating m~ans may o:E course be applied as wel.l.
A ~urther possible height acijustrnent o~ container 19 relative to p~

chassis 1 and hence adjustmen-t o~ the loosening depth is seen in that container 19 including loosening device 21 is height adjustably applied to holder 53'. Such an embodiment is shown in Fig. 3. Container 19 is secured to an intermediate holder 68, which forms together with holder 56' a skid guide. On the intermediate holder 68, there is an extension 69 having a threaded bore passed by a threaded spindle 70, which on its part is supported in a leg 71. At the end opposite ex-tension 69, the threaded spindle includes a crank 72. Between leg 71 and extensi.on 69 pressure spring 73 is provided, which absorbs the vibrations and shocks transmitted irom the loosening device 21 to the container 19 and hence to the intermedi.ate holder 68.
Bei'ore canmencin& with the repair of a longitudinal crack in a road suriace, the constructional unit 15 comprising burners 13 and the heating device lO is lowered in the direction of the road, and subse-1~ quently, by correspondingly height adjustlng the tw~ rear wheels 3 andsimultaneously ti].ting lever 62 by means Oe pneumatic operating cylin(ler 64, the desired loosening depth is a~justed. Care should in this connection be taken that the skids 26 are ali~ned in parallel relat:ive to th0 road sureace ~Id that they rest complete~ly to the road. I~y ~ actuating screwed spindle 31, the hei~ht oi wall 30 and oe th0 .ei.n.i.;hing screed has to be adjusted. 'l'h.i.s ~djustn~nt depends inter alia on the depth of the cr ~ to ~e repaired. l~articularl.y in the case Or a ~reat depth oi' the crack, the heating device 12 restin~r on ski.ds 74 shou:Ld iinaLly ~e coupled to contaLner 19. The various heatin~ devices having ~5 been put lnto operation, the repair w~rk can begin. l'he gas-air mixture ejected under higrh pressure by the burners will clean the crack and : remove any h~nidity in it. Subsequently, the crack itselY and i-ts immediate neighborhood is heated by heating device 10 and subsequentl.y by heating device 11. The heated area of the crack is subsequently loosene~ by the chisels 26 provided on roller 22 and the loosened particles are additionally crushed by the chisels. Together with the loosening and crushing of the old road coating, admixing of new coating material from container 19 is accomplished. The old and new coating material intimately blended by chisels 26 is subsequently pressed via polishing screed 36 into the broadened crack, is preconsolidated and polished. Subsequently, the sur~ace areas of the coating material in the crack is heated again and immediately thereafter the coating material is subjected to a final consolidation by means of a connon road roller.

In another embodiment according to Fig. 3, loosening device 21 is directly swivellingly secured via guide organ 58, pri.smatic guide 59, holder 56 and roller 55 (see Figr. 2) and height-adjustably via wheels 3 to the chassis.
In relation to this loosening device 21, the container 21 is height-ad~ustable by screwed spind:Le 70, and pressure spring 73 provides 2~ that the contalner gliding on the ground may evade any unevenness ol' the ground, but on the other hand will always Lrlide on the ground ~Id thus limit th~ blending space for the c.rushed old coatlng materi~l and the new coating material i.rrespect:i.ve of which loosening depth i.s desired,

Claims (16)

Patent Claims

1. A method for repairing ruptured longitudinal seams or cracks in road surfaces which consist of a thermoplastic material and particularly asphalt by which, under the application of heat, new coating material is applied, and consolidated, in the area of said longitudinal seams or cracks, wherein as a first step mud and humidity is removed from, and out of, said longitudinal seam or crack, said longitudinal seam is subsequently softened by heating, said softened coating is loosened from the underground and is compounded with the new material and/or liquid or liquified aggregates and is finally incor-porated and consolidated again.

2. A method according to claim 1, wherein said compound comprising old coating material and new coating material and/or aggregrates is subjected to a further heating step prior to consolidation.

3. A method according to claim either 1 or claim 2, wherein in order to improve adhesion, the road surface to be treated is sprayed with liquid or liquified aggregate prior to the incorporation of said material.

4. Apparatus for performing the method according to one of claims 1 through 3 comprising a chassis including an own drive engine and wheels and/or caterpillar tracks and including at least one heating device and means for loosening the road coating arranged behind it, as seen in the direction of motion, wherein as the means for loosening said road coating a small roller provided with chisels and rotating in a direction opposite to the direction of motion is provided, which roller is arranged in the discharge area of a container holding said new coating material such that when rotating said roller in the discharge area of said container, compounding of the old coating material trans-ported up by said chisels and of the new coating material is accomplished.

5. Apparatus according to claim 4, wherein a container including a dosing device for liquid or liquified aggregates is provided.

6. Apparatus according to claim 5, wherein said dosing device opens in the discharge area of said container holding the new coating material .

7. Apparatus according to claim 5, wherein said dosing device is connected to a sprayer device covering the whole width of the road surface to be treated.

8. Apparatus according to one of claims 5 through 7, wherein said container for the liquid or liquified aggregates is provided with a heating device.

9. Apparatus according to claim 5, wherein the amount of the liquid or liquified aggregates added by said dosing device is controlled depending on the moving speed of the apparatus.

10. Apparatus according to claim 4, wherein said container at the lower side thereof passes over into a tubular extension of rectangular cross section in which said roller carrying the chisels is rotatably supported.

11. Apparatus according to claim 10, wherein the rear wall of said tubular extension of the container is height-adjustable and includes an extension similar to a finishing screed.

12. Apparatus according to claim 11, wherein at least the lower area of said rear wall and if necessary of said finishing screed like extension are in operative connection with a heating device.

13. Apparatus according to claim 11, wherein in order to height-adjust said container, that pair of wheels of the chassis neighboring said container is height-adjustably secured to said chassis.

14. Apparatus according to claim 12, wherein said container is height-adjustably secured to said chassis.

15. Apparatus according to claim 10, wherein to the two side walls of said tubular container extension one skid each is provided.

16. Apparatus according to claim 4, wherein for removing mud and humidity from the longitudinal seam to be repaired or from the longi-tudinal crack to be repaired, respectively, liquid gas operated burners are arranged in front of said heating device.