Note: Descriptions are shown in the official language in which they were submitted.
This Application is a Division o~ Canadian Patent Application
263,260, ~iled October 13,1976.
This invention relates generally to roadway rcsurfacing apparatus,
and more particularly to new and improved asphalt concrete recycling methods
and apparatus for rejuvenation of old roadway surfaces which require little
or no new asphalt concrete hot mix material to be added to the process.
Accordingly, this invention deals with substantial improvements in the form-
ing and handling of rejuvenated roadway surfaces during road repaving
operations. ~-
Road resurfacing apparatus, in general, as set forth in Cutler
United States Patent No. 3,361,042, provides means for quickly and inexpen- ~-
ively resurfacing roadways made o asphalt concrete material. The si~e of
the apparatus disclosed therein is on the order of about eight to ten feet
wide and approximately forty to fifty fee~ long and is intended to move along
the roadway at a slow rate of speed so that during a single continuous pass,
the old road surface is excavated and combined with additional hot mix to
form a new road surface. During the conversion of the old road surface to
the new road surface, substantial amounts of new asphalt concrete mixtures
are required to be added to excavated material. This is to compensate for
missing material as a result of pot holes in the road and to provide a thicker
road surface.
While this method of resurfacing roads comprises a substantial
improvement, it does require an extensive source of new hot mlx of asphalt
concrete during the resurfacing operation. Also the new road surface is
raised one or more inches and therefore requires that gutters and shoulders
along the sides of the road be elevated for proper drainage and road safety.
Another problem with prior art road resurfacing ap~aratus is that
; the leading edge of the leveling screed is subjected to a relatively high
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degree of wear. In many cases the upwardly turned leading edge of the screed
wears through, thereby allowing the hot mix of asphalt concrete to enter the
interior of the screed. When this happens the new road surface is not leveled
and compacted properly and the screed must be replaced. Therefore, the road
resurfacing operation must stop for a relatively long period of time while
the entire screed is replaced.
The parent of this application is direc~ed to a method of and an
apparatus for restoring an asphalt roadway.
According to one aspectJ the invention of this application provides
a screed structure for use in apparatus of the type described comprising a
bottom plate member engageable with a surface to be processed, a front edge
member adjustably fixed along a forward edge of said plate member, said front
edge member including a plurality of circumferentially spaced wear surface
portions, and means adjustably fixing said front edge member for enabling
said wear surface portions selectively to be presented for engagement with a
surface being processed.
According to another aspect of the invention there is provided a `~
material mixing and spreading apparatus for use on a roadway processing
vehicle movable in a predetermined direction comprising support frame means,
a plurality of augers rotatably mounted on said support frame means and extend-
ing transversely of said direction of movement for engaging and transversely
moving loose material on a roadway surface, and blade means immediately ad~a-
cent and behind certain of said augers for engaging and retaining a portion
of the loose material in association with said certain of said augers for
promoting mixing and transverse movement of said portion of loose material,
and other augers being located behind said blade means for promoting spreading
of the loosened material over the roadway, and a screed structure comprising
a bottom plate member engageable with the spread, loosened material, a front
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edge member adjustably fixed along a forward edge of said pla~e member, said
front edge member including a plurality of circumferentially spaced wear
surface portions, and means adjustably fixing said front edge member for
enabling said wear surface portions selectively to be presented for engagement .
wi~h the spread, loosened material. :
According to a further aspect the invention provides apparatus for
restoring a roadway, comprising means for excavating the roadway surface, means
for applying a quantity of asphalt to the excavated heated surface to form a
rejuvenated asphalt mix~ and vibrating screed means for compacting the reju- -
venated asphalt mix, said vibrating screed means including a bottom plate
member engageable with the rejuvenated asphalt mix~ a front edge member adjust-
ably fixed along a forward edge of said plate member, said front edge member
including a plurality of circumferentially spaced wear surface portions, and
means adjustably fixing said front edge member for enabling said wear surface
.~ portions selectively to be presented for engagement with the rejuvenated asphalt ~:
mix, the screed means further including a yieldable bottom plate, and means for
flexing the yieldable bottom plate in accordance with the radius of curvature
of the road surface being restored to form a crown for the road surface. ~.
In the accompanying drawings, which illustrate exemplary embodiments
of the present invention:
FIGURE 1 is a side elevational view schematically showing the various
work stations and steps of operation of a road resurfacing apparatus;
FIGURE 2 is a top view of the schematic showing of FIGURE l; ~
FIGURE 3 is a side elevational view of a road recycling machine .
wherein the various work stations shown schematically in FIGURES 1 and 2 are ~-
located~
FIGURE 4 is a top view of a mixer and leveler apparatus constructed
in accordance with one aspect of this invention and located within the machine
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of EI~URE 3;
FIGURE 5 is a side view of the mixer and leveler apparakus of
FIGURE 4;
FIGURE 6 is a sectional view taken substantially in the plane of
line 6-6 in FIGURE 4;
FIGURE 7 is a sectional view taken substantially in the plane of
line 7-7 in FIGURE 6;
FIGURE 8 is a perspective view of a leveling screed which is con-
structed in accordance with other aspects of this invention;
FIGURE 9 is a top view of the screed;
PIGURE 10 is a front view of the screed;
FIGUR 11 is an end view of the screed;
FIGURE 12 is a top view showing in schematic form another embodiment
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o~ th~ invention; and
~IGURE 13 is a side elevational view of the schematic showing of
FIGURE 12.
Referring now to PIGURES 1 and 2, there is seen a schemat~c arrange-
ment of the work stations associated with a road repaving machine which is
designated generally by reference numeral 10. The road repaving machine 10
includes a pair of spaced-apart radiant heating units 12 and 14 located near
the front end thereof to provide heating of the pavement surface 16. The
radiant heating units 12 and 14 are operated by a fuel mixture comprising
propane and air of the appropriate proportions. The propane-air fuel mixture
is applied to a plurality of radiant heating burners or elements within the
units to generate uniform radiant rays over the area covered by the heating
units. These rays are directed toward the black asphalt cement of the pave-
ment surface 16, and penetra~e to a depth of between one to three inches
without burning the asphalt cement or polluting the surrounding atmosphere.
.,
l~e radiant heating units 12 and 14, as well as the radiant heating burners
mounted therein, can be constructed substantially as set for~h in my earlier
, Patent No. 3,g65,098 which issued February 11, 1975.
; The direction of travel of the road repaving machlne 10 is indicated
by an arrowed line designated by reference numeral 18. Immediately follo~ing
the heating operation of the pavement surface by the radiant heat of the
units 12 and 14, a quantity of asphalt may be applied to the heated pavement
surface by means of a plurality of spaced-apart nozzles 20, i-f desired or if
road conditions require. Thus a thin film of asphalt is applied to particles
which are to be excavated from the road surface for forming a rejuvenated hot
mix.
The excava~,ion of the road surface is accomplished by scarifying
blades 21 which are located at a scar~fying statlon 22 of the road repaving
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apparatus 10. Preferably, the scarifying blades 21 are urged against the
road surface by means of air-operated bags which apply pressure to scarifying
blade holding arms 23. The scarifying blades 21 excavate the heated and
coated road surface to a depth of between one-half inch to three inches~ and
preferably in the order of about 3/4 inch to 1~ inches. The scarifying blades
21 can be carbide tipped for maximum wear resistance. The scarifying blade
and air bag operating controls are described and illustrated in Cutler United
States Patent No. 3,907,~50, dated September 23, 1975.
Immediately following the excavation of the road surface by the
scarifying blades 21, a second quantity of emulsified or heated asphalt is
applied to the now loose and heated surface. This asphalt, sometimes commonly
referred to as liquid asphalt, restores the adhesion property of the asphalt
aggregate which i5 to be recombined ~o form ~he reclaimed or rejuvenated hot
mix for the road surface. The asphalt is applied to the excavated by means
of a plurality of rotating liquid dispensers 24 which are immediately behind
the scarifying blades 21. Preferably the dispensers 24 receive liquid
asphalt from the same container as the nozzles 20.
A quantity of rejuvenator llquid is also applied to the excavated
asphal~ ma~erial by means of a plurality of rotating dispensers 28. The
rejuvenator liquid restores the flexibility to the asphalt concrete mlx.
The combination of the excavated road surface together with the liquid asphalt
and the rejuvenator liquid provides a hot mix of asphalt material with con-
forms substantially to the charac~eristics of the new hot mix normally used
for paving and repaving roadways. ThereforeJ the asphalt concrete repaving
apparatus 10 substantially completely eliminates the need to add large
amounts of new hot mix asphalt concrete material to the road surface when
repaving or rejuvenating such road surfaces.
If a quantity of new hot mix asphalt concrete is required or
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desired, it is supplied at the work station designated generally by reference
numeral 30 which is located immediatel~ following the rejuvenating applicat-
ors 28. The work s~ation 30 receives a new quantity of hot mix from the side
of the repaving machine 10 by means of a dump truck which is designated
generally by reference numeral 32 which applies the new hot mix asphalt con-
crete material therein to a portable conveyor 36. The conveyor 36 moves the
material in the direction indicated by an arrow 38 in FIGURE 2 to the work
station 30. Also at the work station 30 a quantity of anti-skid chips may
be added to the reclaimed hot mix if desired. The conveyor 36 may be carried
by the truck 32 or it may be moved manually on its own wheels.
rmmediately following the formation of the rejuvenated hot mix and
the addition of any new hot mixJ the material is further mixed and leveled
by a pair of mixing screws 40 and 41 which traverse the rejuvenated hot mix
first in the direction indicated by arrow 42 and then in the direction
indicated b~ arrow 43. Associated with each o~ the mixing screws are le~el-
ing blade 44 and 46 resp~ctively. The newly formed rejuvenated hot mix
(together with whatever small amounts of new ho~ mix have been added~ is
thoroughl~ mixed to comblne the loosened aggregate and the liquid asphalt and
rejuvenator. This operation is followed by a second pair of mixlng and
spreading screws 48 and 50 which move the reclaimed hot mix first in the dir-
ection indicated by arrow 51 and then in the direction indicated by arrow 52.
This operation uniformly disperses the reclaimed hot mix together wit~ what-
; ever new hot mix has been added. If necessary, additional heat is applied to
the mix ~y~means of a plurality of independent heating units 54 which enable
the material to be more easily compacted and shaped by means of a formable
vibrating screed 56.
The screed 56 is formed of a plurality of sections 56a, 56b, 56c
and 56d. These sections are interconnec~ed by turnbuckles and rods, to be
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described in greater detail hereInbelow. These turnbuckles and rods enable
the lower sur~ace 58 of the screed to be shaped in conformity ~ith the
contour of the road surface being formed. Most advantageously, the vibrating
screed compacts the reclaimed, rejuvenated, hot mix to a compaction of more
than 85%. However, it will be understood that the degree of compaction
achieved at this work station can vary widel~ without departing from the
spirit and scope of the novel concepts of this invention.
If desired, the road surface may be provided with a scattered single
layer of coated lightweight nonskid synthetic aggregate. This aggregate
material is dispensed from a hopper and spreader 62 over the substantially
completely compacted road surface. The amount of coated chips applied to
the newly formed road surface may be in the order of about three pounds of
aggregate chips per square yard of road surface. However, other amounts may
be dispensed if desired. The road surface is ultimately compacted by a roller
vehicle 64 which applies substantial weight per unit area of road surface to
achieve 100% compaction of the newly rejuvenated asphalt concrete material.
Referring now to ~IGURE 3, there is seen a side elevational view of
a road repaving machine whereln the plurality of work stations illustrated
schematically in FIGURES 1 and 2 are located. The repaving machine 10 has
the forward burner 12 separated from the second or rearmost burner 14 by
wheels 70 and associated undercarriage structure of the repaving apparatus.
The wheels 70 are steerable by hydraulic steering means from a central operat-
ing station 71. Also, if desired, the area between the wheels 70 may include
scarifying apparatus ~not shown) to perform an ini~ial excavation in the road
surface before the second heater 14 applies radiant heat thereto. The heating
units 12 and 14 include a plurality of exhaust stack~ 72 and 73, respectively,
through which the products of combustion from the burners are expelled.
The road repaving apparatus 10 includes a rear lower ~rame structure
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78 which supports the mixing and 10veling screws ~0, ~1, 48 and 50. Also
at the end of the support frame 78 is secured the compacting vibrating screed
56. The road repaving machine 10 also includes a pluralit~ of csntainers 79
for supplying liquid such as diesel fuel for diesel engines used to power the
machine, propane fuel for burners 12 and 14, water for cooling various com-
-~ ponents of the apparatus when necessary, liquid asphalt and rejuvenating
materials.
Referring now to FIGURES 3, 4 and 5, there is seen the details of
construction of the leveling and mixing screws 40, 41, 48 and 50. Also some
of the details of the support frame 78 are shown. The support frame 78
includes an elongated fixed member 80 secured to the chassis of the repaving
apparatus which is indicated generall~ b~ the reference numeral 81. The
member 80 is pivotall~ secured to the chassis 81 by a pin means 82 or other
suitable fastening means. An associated member 84 is adjustable relative to
t~e member 80 and includes means for adjusting the relative positions of
the mixing screws 40 and 41 and with the associated back-up blades 44 and 46.
The mixing screw 40 is journalled at its ends b~ bearing means 87
which may ~e secured to a flange or other suitable means 88. Similarly, the
mixing screw 41 is journalled by bearing means 89 secured within a flange
2~ or bearing support 90. On the other hand, both screws 48 and 50 are secured
to the elongated member 80 by means of plates 91 on opposite sides of the
frame structure. The plates 91 receive means for carr~ing a pair of bearings
92 and 93 for journalling the auger type mixing screws at their ends. A
leveling wheel 94 is secured to an adjustable member 96, which, in turn,
is inserted into a guide 97. The adjustable member 96 includes a threaded
rod 98 secured to the elongated member 80. The vertical position of the mix-
ing and leveling screws 48 and 50 can be adjusted by raising and lowering the
guide roller 94 b~ means of the threaded rod 98. To compensate for the cro~n
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or cross-s~ctional c~lrva~ure of ~he road, th~ leveling blades 44 and 46 are
p~vo~ally secured to the frame ~y p~ns lOOa and lOOb, respectively.
As best seen in ~IGURF: 4, the excavated, rejuvenated hot mix is
conveyed by the mixing screw 40 in the direction as indicated by the arrow
100 to an area 101 immediately in ront of the next auger mixing scr0w 41.
The auger or mixing scre~Y 41 conveys the rejuvenated hot mix in the direction
of arrowed lines 102 where it leaves the scre~ in an area immediatel~ adjacent
the auger screws 41 and behind the auger screw 40~ The blades 44 and 46 cause
substantial amounts of the material to pile up within thelr associated auger
screws to insure the desired mixing ac~ion.
As the repaving apparatus advances forward, the piled rejuvenated
hot mix is then agitated and dispersed by the leveling screw 48 wherein the
material directed in the direction of arrowed lines 103. The rejuvenated
hot mix is again subjected to mlxing and leveling by the auger 50 which moves
the material in the d~rection as indicated by arrowed lines 1040 Since
there are no blades associated with the screws or augers 48 and 5Q, the pil-
ing is minimized and substantial leveling i~ accompllshed.
Referring no~ to ~IGURES 4, 6 and 7, the details of construction
of the forward mixing and leveling screws and associate leveling blade$ are
shown. As mentioned above, the leveling auger screw 40 is journalled by a
bearing 87 in a support 88. As seen in FIGURE 6, the bearing is secured to
a beam 121 and extends therefrom by means of an arm 122. Preferably, location
of the beam 121 can be altered by an adjusting screw 124 or the like to
provide a crown control adjustment for the cross-section of the road surface.
The adjusting screw 124 may either be rotated manually or by means of an
electric motor 125 operated by a suitable control circuit.
The beam 121 is pivotally secured by means of the pin lOOa Which
is connected to a support frame 126 which is fixed ~o the upper support beam
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sn. The ro~ating auger screw 40, toget~er with its l~vellng blad0 44, there-
fore pivot about the pin lOQa by means of the adjusting screw 124. Similarly,
the auger screw 41 toge~her with i~s leveling blade 46 are pivotally secured
to the frame 126 by the pin lOOb which, in turn, is secured to a beam 127.
The ~eam 127J together with the associated auger screw 41 and leveling blade
46 are pivotally adjustable a~out the pin lOOb b~ an adjusting screw 130,
whichalsomaybeeither manually operable or driven by a motor 131 in response
to suitable control circuitry.
During machine operation, arms 141 and 142 (FIGURE 7) enable the
associated beams 121 and 127 to move upwardly and downwardly in response to
action of the adjusting screws 124 and 130. Also, the arms 141 and 142 pro-
vide a back-up support for the leveling blades 44 and 46 as the~ are urged
against the mass of rejuvenated hot mix asphalt concrete material. ~hile a
single specific embodiment is illustrated herein for providing cro~n control
of the rejuvenated hot mix formed b~ the repaving machine of this invention,
it ~11 be understood that other suita~le crown control means can ~e incorpOr-
ated if desired.
Each section 56a - 56d of t~e screed 56 includes an initial leading
edge member formed by a hollow pipe 106 which is secured to the screed bod~
2Q designated generall~ by reference numeral 107, as shown in FIGURES 4, 5 and
8-11 inclusive. The screed body 107 includes a bottom plate 108 extending
the width of the screed and U-shaped upper members 109 forming front, rear
and top walls for each of the sections 56a - 56d. As shown in FIGURE 5, the
screed 56 is urged downwardly by means of an adjusting screw 110 which engages
a threaded coupling 111 extending from the elongated member 8~. A hand crank
112 is provided for adjusting the level of the screed as well as the amount
of pressure or force transferred from the elongated member 8~ to the screed
for compacting the newl~ laid road surface. The screed 56 includes standing
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walks or platforms 113, 114, 115 and 116 associated with the sections 56a,
56b, 56c and 56d, respectively. The standing platforms enable workmen to
stand immediately behind the screed and operate the adjusting screws 110 and
other equipment to insure thak a uniform road surface is formed. Also, it
will be noted that the pipe 106 forming the leading edge ~f each screed sec-
tion is heated by the heating apparatus 54 to insure that the hot mix is
sufficiently flowable under pressure to facilitate compacting of the material.
Referring more particularly to FIGURES 8-11, there are seen the
details of construction of the screed 56 utilized in the road repaving appar-
atus 10. The leveling screed 56 is adjustable along its width to provide
an arcuate surface configuration for conforming to the crown of the road as
f~rmed initially by the leveling blades 44 and 46. The screed is vibrated by
a plurality of motor driven vibrators 160, 161, 162, 163, 164 and 165. Each
vibrator 160 - 165 preferably rotates in a direction opposite to that of the
adjacent vibrators. For example, the vibrators 160, 162 and 164 may rotate --
in a clockwise direction while vibrators 161, 163 and 165 may rotate in a
counter-clockwise direction, when viewing the screed from the rear of the
apparatus.
A heating chamber 167 is provided immediately over the pipe leading
2Q edge 106 of the screed and wherein the plurality of heating units 54, FIGURES
1 and 2, are located. The heating chamber 167 has a pair of exhaust stacks
168 and 169 extending upwardly therefrom to remove the products of combustion.
Preferably, the heating units are of the radiant heating type similar to those
utilized in the heating units 12 and 14 and disclosed in Cutler United States ;
Patent No. 3,685,098.
The ends of the screed include socket structures 170 and 171 to
receive adjusting screws similar to the adjusting screw 110 illustrated in
PIGURE 5. As best seen in PIGURES 9 and 10, the screed sections 56a - 56~
are disposed in closely adjacent side-by-side relatlonships ~or bracing the
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bottom plate 108 and disposing it in a desired road surface-forming shape.
The section 56a includes a pair of vibrakor mounting brackets 176 and the
section 56b includes a pair of vibrator mounting brackets 177. Similarly,
the section 56c includes vibrator mounting brackets 178 and the section 56d
includes vibrator mounting brackets 179. While only four sections and four
pairs of mounting brackets are shown in FIGURES 9 and 10, it will be under-
stood that six vibrators can be incorporated as showrl in the perspective view
of FIGURE 8. Also it will be understood that an~ number of sections similar
to the sections 56a - 56d can be incorporated, this varying from, for example3
10 four to eight sections, depending on the width of the road repaving apparatus.
The section 56a has a pair of access plates 180 and 181 secured over access
apertures in its top member lO9 by lock ~abs and bolts indicated generally
; by reference numeral 182. The sections 56b - 56d have similar pairs of
access plates 183 and 184, 187 and 188 and 190 and 191, secured over openings
in their top members 107 by means of lock similar tabs and bolts.
As explained above, the sections 56a - 56d are adjustable relative
to one another and the plate 108 is sufficiently flexible to allow the sect-
ions to be relatively pivotable about axes between th sections indicated by
reference numerals 200, 201 and 202. This enables the screed plate 108 to
20 be adjustably curved or arched so as to conform to the desired crown of the
~oad surface.
To adjust the section positionsJ the sections 56a and 56b are tied
together at their upper ends by turnbuckle means 204 which extends bet~een a
pair of upstanding plates 206 and 207 on the sections 56a and 56bJ respective-
ly. The turnbuckle means 204 includes forward and rear turnbuckle elements
204a and 204b, as seen in FIGURE 8, which are coupled by a drive chain 209
which can be either manually or automatically driven to rotate the turnbuckles
204a and 204b simultaneously so as to effect uniform flexure of the forward
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and rear portions of the sections 56a and 56b.
Sections 56b and 56c are adjustably connected by turnbuckle means
210 extending between upstanding plates 211 and 212. The turnbuckle means
210 also includes a forward turnbuckle 210a and a rear turnbuckle 210b, as
seen in FIGURE 8, and these turnbuckles are tied together by a common drive
chain and sprocket arrangement indicated generally by reference numeral 213.
The sections 56c and 56d are also adjustably secured together by additional
turnbuckle means 216 mounted between upstanding plates 217 and 218. The
turnbuckle means 216 includes a forward turnbuckle 216a and a rear turnbuckle
~ 10 216b tied together by a chain and sprocket arrangement 220.
; The details of only one of the turnbuckles will be set forth
herein, it being understood that the turnbuckles are all constructed in
substantially the same manner. The turnbuckle 216a includes a pair of thread-
ed shafts 221 and 222 extending from a threaded body 223. The shafts 221 and
222 are secured to brackets 226 and 227, respectively, moun~ed at the top ends
of the plates 217 and 218. The brackets 226 and 227 preferably are welded in
position. Thethreaded member 223 has fixed to it a sprocket 229 engaging a
chain to form the sprocket and chain adjusting arrangement 220. By operating
this turnbuckle, the plate 108 is flexed about the axes 200, 201 and 202 to
obtain the desired curvature.
The leading edge of screed 56 is formed by the aforementioned pipe
or edge member 106, which, as seen in FIGU~E 10 comprises separate sections
106a, 106b; 106c and 106d respectively incorporated in the screed sectîons
56a - 56d. As seen in FUGURE 11, the pipe sections 106a - 106d are secured
to the screed sections by bolts 240 which engage threaded ap0rtures 242,
243, respectively, formed within the pipe. A second set of threaded apertures
244 and 246 are formed diamekrically opposed from the apertures 24~ and 241,
respectively. This enables the pipe or edge member sections to be removed
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from the position shown in the drawlngs, rotated 90, and then resecured in
a position at the leading edge of the screed. In this instance, the pipe
would be secured by the threaded apertures 242 and 244 when rotated counter-
clockwise 90, or secured by threaded apertures 242 and 246 when rotated clock-
wise 90. Thus, the pipe is capable of providing multiple wear surfaces for
engaging the abrasive asphalt concrete material as the repaving machine
passes over the road surface. For example, the quadrant designated by refer-
ence numeral 247 is the wear surface presently disposed for engaging the
asphalt concrete material during the repaving operation. However, when the
quadrant 247 is substantially worn, the pipe edge member can be moved and
rotated to expose a new quadran~ 248. Similarly, when this wear surface is
depleted, the pipe or edge member may again be rotated to expose another new
wear surface 249. Finally, a last wear surface 250 may be put into operation
by again rotating the pipe. The screed 56 therefore provides a multiple ~ear
surface device at the leading edge of the screed complacting plate or bottom
wall 108.
An alternate embodiment is illustrated in FIGURES 12 and 13. Here
a machine 310 includes preliminary heaters 312 and 314 like those described
in connection with FIGURES 1-3. Nozzles ~not sho~n~ can be included if de$ir-
ed to appl~ a preliminary coating of liquid asphalt to the heated pa~ement
if desired or if road conditions require. These nozzles can be conveniently
located between the heaters 312 and 314 or behind the second heater 314.
Scarifying blades 321~ mounted at a scarifying station 322 are urged against
the road surface by air operating bags 323 which apply pressure to scarifying
; blade holding arms 324. As noted above, the scarifying blades and air bag
operating controls are described and illustrated in Cutler United States
patent No. 3,907,450, dated September 23, 1975.
Behind these scarifying blades 321 are windrowing augers 330 and
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331 ~h~ch are arranged and rotated so as to conve~ the now-loosened and
scarified materIal toward t~e cent~r of the machlne travel path as indicated
by the arrows 332 and 333 in ~IGURE 12. slades 335 and 336 mounted behind
the augers 330 and 331 respectively assist in presenting scarified material
to the augers for this centralized movement. Behind the augers 330, 331 and
and blades 335, 336, liquid dispensers 340 and 341 apply hot liquid asphalt
` and any desired rejuvenating agent to the scarified and now relatively denuded
remaining highway surface. These dispensers can be arranged, if desired,
to also add asphalt to the scarified and windrowed material.
At the front or any other convenient location upon the machine 310,
a receiving hopper 350 is located to receive a quantity of hot mix 351 from
a supply 352 in a truck 354 or other delivering unit. This hot mix 351 is
conveyed from the receiving hopper 350, as by a conveyor 355, to a delivery
and dispersing position 356. At this position, the newly delivered hot mix
351 is deposited atop the ma~erial scarified and windrvwed by the blades 321
- and augers 330, 331. An agitator device 360, here comprising a series of pug-
mill paddles 361 and an associated backup plate 362, agitates and intermingles ~ ,
this newly delivered hot mix 351 and old road material to provide a new road- -
forming composition. If desired, this paddle wheel 360 can be formed so
` 20 as to provide a spreading action to the composition as indicated by the arrows
365 and 366.
Behind the agitating paddle wheel 360, additional spreader augers
370 and 371 are oriented and are rotated so as to further spread and level
the new composition as indicated by the arrows 372 and 373. ~ screed
mechanism 380, which can be of the type described above, is provided to level
; and preliminarily compact this composition into a new road surface. ~aterial
spreaders 385 and 386 can be provided to scatter a layer of nonskid synthetic
aggregate atop the new road surface. It will be understood that a roller
- 15 -
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~)73'~2~il
yefiicle 388 or other compactor device can be used to achieve lOQ% of the
des~red compaction ~or t~e newl~ rejuvenated asphalt concrete material and
- recycled r~ad.
- 16 -
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