FR2675522A1 - DEVICE FOR PRODUCING A ROAD COVERING BY SUCCESSIVE SPREADING ONTO THE ROAD SURFACE TO BE COVERED, A HANGING LAYER AND A LAYER OF HOT BITUMINOUS MATERIAL. - Google Patents

Abstract

The device consists of a motorised mobile unit (1) comprising, from the front towards the rear in its direction of travel on the road surface, a means (8) for receiving hot bituminous mixtures, a device for transferring the hot bituminous mixtures towards the rear of the mobile unit (1), a device (16) for spreading the bituminous mixtures and a compacting and smoothing table (17) as well as a spraybar (18) for spraying bitumen emulsion, which can extend in the transverse direction. The extensible spraybar (18), consisting of two spraybar elements (18a, 18b) which can move relative to each other in the transverse direction, is placed at the rear part of the mobile unit (1), in front of the device (16) for spreading the bituminous mixtures, with a spacing of less than one metre. The spraybar comprises an additional means for spraying and measuring out bituminous liquid in the interface zone between the two spraybar elements (18a, 18b).

Description

The invention relates to a device for producing

  tion of a road surface by successive spreading on

  the road surface to be covered with a layer of

  chage consisting of a liquid bituminous product such as a bitumen emulsion and a layer of hot bituminous material incorporating aggregates, such as a

  coated, the spreading width of the two products can

  before being continuously adjusted between two extreme positions

  my. A process is known for producing a road surface consisting of bituminous mixes produced hot or cold, the adhesion of the coating layer on the road surface being ensured by

  a layer of a liquid bituminous binder which is generally

  LEMENT consisting of a bitumen emulsion.

  In the case where the coating is constituted by a hot bituminous product such as a coated containing

  aggregates (in particular pebbles of different

  your grain sizes), bitumen, a powdery material as well as any other additives, the mix can be spread on the road previously coated with the bonding layer, at a temperature of about 1500 C. Conventionally, the liquid bituminous binder constituting the bonding layer is spread on the road before spreading the hot mixes, sufficiently in advance so that the bitumen of the layer

  can be separated from the solvent or optionally-

  lement of water in the case of the use of an emulsion, by evaporation of the solvent or water in air

free.

  The liquid bituminous binder is spread on the road by a spreader completely independent of the

  device used to spread the enro-

  be, then its compaction and its smoothing.

  In European patent 0 049 260 filed by the Swedish company AB SKANSKA CEMENT GUTIERIT, it has been proposed to spread the granular bituminous product such as a coated material, on the adhesion layer, immediately after the spreading of this layer of bonding on the road Unexpectedly and, in particular in the case where the bonding layer consists of an aqueous bitumen emulsion, drying and breaking of the emulsion under the effect of the heat of the hot mixes entail an improvement in the qualities of the

  bonding layer and therefore of the coating produced.

  In addition, this avoids, to a large extent, deteriorating the bonding layer by the passage of gear on this still liquid or broken layer in the case of use of bitumen emulsion

  spread well before spreading hot mixes.

  Various devices have been proposed for applying this method, in the case of a layer of

  coating consisting of asphalt or other pro-

  road surfacing mixes incorporating aggregates and

  pulverulent materials bound by a bituminous material

  neuse. In particular, it has been proposed to use a device for spreading, compacting and smoothing asphalt for road surfacing, generally called a paver, for simultaneously carrying out the spreading of the liquid bituminous binder of the bonding layer. .

  The finishers known in the prior art

  generally consist of a mobile motorized assembly comprising, from front to rear of the mobile assembly in its direction of movement on the road surface, a means for receiving granular bituminous materials, a device for transferring bituminous material towards the rear of the mobile assembly, a device for spreading out the granular bituminous material and a table for compacting and smoothing

  the layer of material spread on the road.

  When a bituminous binder spreading ramp

  neux intended to constitute the bonding layer is integrated into the paver, this ramp is arranged at

  front of the paver, so the wheels or kennel

  those of the mobile assembly are caused to circulate on the layer of freshly spread bituminous binder It is therefore necessary to provide additional ramps

  arranged at the rear of the wheels or tracks of the assembly

  movable grain to reconstitute a bonding layer

substantially homogeneous.

  In addition, the pavers are intended to produce pavements on pavements of variable width, so that it is necessary to provide ramps made up of separate mobile elements whose relative position in the transverse direction is adjustable. The result is a complex arrangement of

  delicate ramps and adjustment conditions

  constituent elements these ramps, to achieve a bonding layer as homogeneous as possible The homogeneity of the bonding layer is generally defective, in the areas of overlap of the ramp elements and in the areas of passage of the wheels or tracks of the pavers . In addition, the emulsion reserve which can be transported by the finisher is limited, so that

  the finisher's autonomy on site is insufficient

  you. These problems have been at least partially resolved, in the case of more complex assemblies intended in particular for the production of thin layer coatings of special types as described in patent application 89-09893 of July 21, 1989 filed by the

  SCREG ROUTES AND PUBLIC WORKS.

  In the case of finishers comprising a smoothing table with lateral extension, it has also been proposed, in patent application 89-12132 filed on July 31, 1989 by the company SCREG ROUTES ET TRAVAUX PUBLICS,

  to associate the extensible ramp elements with the elements

  adjustable elements of the smoothing table The device which is the subject of this patent application also comprises means making it possible to obtain a substantially homogeneous bonding layer in the areas of

  covering of the different ramp elements.

  However, in the case of a type finisher

  classic with adjustable working width, we do not know

  hitherto no device for spreading a bituminous binder such as an emulsion, integrated into the paver, which makes it possible to remedy all the drawbacks associated with the operation of pavers with integrated ramp known from

prior art.

  The object of the invention is therefore to propose a device for producing a road surface by successive spreading over the road surface to be covered, with a bonding layer constituted by a liquid bituminous product, such as a bitumen emulsion. , and a layer of hot bituminous material incorporating

  aggregates such as a mix, consisting of a seed

  motorized mobile wheat comprising, from front to rear

  re in its direction of movement on the road surface, a means for receiving the granular bituminous material, a device for transferring the bituminous material to

  the rear of the mobile assembly, a spreading device

  dage of bituminous material and a compacting table

  and smoothing the layer of dual granular material

  as well as a bitu product spreading ramp

  miners with extension in the transverse direction, ali-

  mented by a liquid tank of sufficient capacity

  containing a liquid such as an emulsion, this dispo-

  sitive making it possible to produce a completely homogeneous bonding layer over a width of road surface identical to the width of spreading of the coated materials and

  avoid any deterioration of this bonding layer

  age before spreading the granular bituminous material

such as a mix.

  For this purpose, the extendable ramp made up of two ramp elements with relative movement in the transverse direction is arranged, at the rear part of the mobile assembly, in front of the device for spreading bituminous products with a spacing of less than one meter relative to to this spreading device, and comprises an additional means for spreading and metering bituminous liquid in the interface zone between the two ramp elements, in order to allow the

  infinitely adjustable working width.

  In order to clearly understand the invention, we

  will now describe, by way of non-limiting examples,

  tifs, with reference to the attached figures, several embodiments of a device according to the invention. Figure 1 is a side elevational view of a device according to the invention, of the finisher type

with adjustable working width.

  Figure 2 is a perspective view of the

  rear part of the finisher shown in Figure 1.

  Figure 3 is a schematic top view

  along 3 of figure 2, from the rear part of the finish

  sister. Figure 4 is a large sectional view

  scale according to 4-4 of figure 3, of a complementary means

  spreading and metering liquid bituminous in the interface area between the two elements of

  ramp, according to a first embodiment.

  Figure 5 is a perspective view of a

  additional means for spreading and dosing liquids

  bituminous in the interface zone between the two

  ramp elements, according to a second embodiment.

  In FIG. 1, a device for producing a road surface of the finisher type with integrated ramp is generally designated by the reference 1. The finisher 1 which is produced in the form of a movable assembly moves, in the course of operation on site, in the direction of arrow 3, by means of tracks 4 driven by a heat engine 5,

  via a transmission assembly 6.

  The frame 7 of the finisher mounted on the tracks

  nilles 4 carries, at its front part, a hopper 8 for receiving granular bituminous products such as hot mixes which are poured into the hopper 8, during the progress of the paver 1 on the site, by a dump truck which can be connected to the finisher 1, via a coupling device 10 placed at the front end of the finisher 1 Tipping

  of the tipper of the truck then makes it possible to carry out the

  pleating of the hopper 8 with hot mixes, without

  interrupt the advance to the paver site 1.

  Cylinders such as 11 fixed between the chassis 7 of the paver and the arm 15 secured to the smoothing table are intended for adjusting the incidence of

table.

  The chassis 7 of the finisher also carries, along its length, a continuous conveyor with bars 12

  the anterior end of which is located under the hopper 8.

  The bar conveyor 12 makes it possible to transport the hot mixes introduced into the receiving hopper 8,

  toward the rear end of the finisher.

  A large-capacity liquid reservoir 13 is also fixed to the chassis 7, between the receiving hopper 8 and the heat engine 5, above the

bar conveyor 12.

  The bar conveyor 12 is driven by the heat engine 5, by means of a set of

  transmission with chain 14.

  Two suspension arms such as 15 are fixed to the chassis 7 on each of the sides of the chassis,

  so as to include a rear part 15 a, outside

  laughing frame ensuring suspension and fixing of the device 16 for spreading bituminous mixes and the table 17 for compacting and smoothing the mixes

  spread on the road surface by the device 16.

  The rear end of the bar conveyor 12

  constituting its outlet end is arranged slightly-

  lying at the front and above the device 16 constituted

  by a screw having two successive parts with reverse pitch

  ses, as seen in Figure 2.

  In this way, the hot mixes brought to the rear of the chassis by the conveyor 12 are evacuated so as to be supported by the screw 16 which ensures the spreading of these mixes along the entire width of the road surface to be coated. and following a

layer of constant thickness.

  A bituminous emulsion spreading ramp 18 comprising two mobile ramp elements 18 a and 18 b

  in the transverse direction one with respect to the other

  tre is placed immediately in front of the device

  spreading 16 of hot mixes.

  When the paver is in operation on the site, the ramp elements 18 a and 18 b comprising spray nozzles distributed along their length are supplied with bituminous emulsion from the

storage tank 13.

  The distance between the ramp 18 and the spreading device 16, along the length of the chassis is small, this length may be of the order of 400 to 500 mm In all cases, this length is less than 1 meter. In addition, the ramp 18 is located entirely behind the tracks 4 for moving the paver 1, so that these tracks 4 are not likely to pass over the layer of freshly-produced bituminous emulsion.

  spread on the road surface, during operation

finisher 1.

  The ramp elements 18 a and 18 b are available

  beneath a protective cover 19 fixed to the chassis 7, below the rear part of the bar conveyor 12 and comprising extensions which follow

  the ramp in its lateral extension.

  The relative arrangement of the spreading ramp

  dage of bituminous emulsion 18, of the spreading device

  Dage of hot mixes 16 and of the compacting and smoothing table 17 makes it possible to carry out successively and with very short time intervals between the

  different operations spreading the bitu-

  leaf spreader, spreading hot mixes and compacting

  tage and smoothing of the coating constituted by the

  hot mixes spread on the bituminous emulsion layer

  neuse. The general structure of the finisher shown in FIG. 1 makes it possible to limit the total length of the machine, by virtue of an arrangement in height and vertically above the bar conveyor, of elements such as the emulsion tank 13, the heat engine and the transmission device 6. The pilot cabin 20 is arranged at the upper part of the finisher, so as to improve the visibility conditions of the driver 21 ensuring

driving the machine.

  In the transport position, the upper part of the driving position can be folded down, so as to limit the height of the finisher. In FIG. 2, we can see the rear part of the paver 1 comprising the compacting and smoothing table 17, the distribution and spreading screw 16 of the hot mixes and the elements 18 a and 18 b of the ramp

18.

  The finishing table 17 comprises a central element or base table 17 a and two lateral elements 17 b and 17 c constituting lateral extensions of the base table 17 a making it possible to vary the width

work of the finisher.

  The base table 17 a has fittings

  side 21 and 21 'which allow the above

  finishing table board at the end parts

  has suspension arms 15 of the paver.

  The central base table 17 a and the extendable side tables 17 b and 17 c include

  known eccentric vibration devices

  that, reciprocating tamping devices and heating means making it possible to carry out the compaction and the smoothing of the common bituminous mixes

on the road surface.

  Each of the fittings 21, 21 'carries colon-

  telescopic nes such as 22 a and 22 b having a movable part slidably mounted in a fixed part integral with the corresponding fitting 21 or 21 'which is connected at its end to a fitting 23 b (or 23 c) constituting the side wall of end of one of the extendable tables

17 b and 17 c.

  The fittings 21 and 21 'integral with the base central table are fixed on arms 24 b and 24 c, themselves connected to the frame of the finisher by the jacks 11 (FIG. 1) for adjusting the incidence and the like.

arm 15 (figure 1).

  The extension of the finishing table 17 is carried out by the cylinder rods 25 and 25 '. The side doors 28 b and 28 c integral with the table 17 each drive an element of the ramp

  18 a or 18 b to adjust the spreading width to the same

that of asphalt.

  The spreading screw 16 has two parts

  successive with reverse steps 16 a and 16 b ensuring the

  tition and spreading of hot mixes over the entire width of the base central table 17 a, as it is

  visible in particular in Figure 3.

  In FIG. 3, the finishing table 17 has been shown in its position of maximum extension, the lateral extensions 17 b and 17 c being in the extension of the central table 17 a.

  extensions 26 b and 26 c have been placed in the extension

  outward extensions 17 b and 17 c respectively. Corresponding extensions 27 b and 27 c of the screw 16 having reverse pitches make it possible to spread the hot mixes over the width

  maximum total working of the finishing table.

  As can be seen in FIGS. 2 and 3, the ramp elements 18 a and 18 b constituting the extendable ramp 18 fixed respectively at their ends to the side doors 28 b and 28 c in positions slightly offset in the longitudinal direction

  allow the emulsion width to be adjusted

  bituminous sion at the working width of the paver which is adjusted by moving the doors 28 b and 28 c,

as shown above.

  Each of the ramp elements 18 a and 18 b has nozzles 29 a (or 29 b) regularly distributed

  along the length of the corresponding ramp and place

  created at a distance from each other.

  The ramp element 18 a has, at its free end opposite the support arm 24 b, an extension slightly offset in the longitudinal direction relative to the ramp element 18 a and carrying a nozzle 31. As is visible in Figure 2, when

  the finisher is in a lower extension position

  re at its maximum extension, part of the ramps 18 has

  and 18 b is placed opposite the central part

  the work area of the paver All the nozzles of the boom 18 a are then open; the nozzles of the boom 18 b, in position interference with those of the

ramp 18 a are closed.

  The variable width zone 35 linked to the extension

  The table is treated by the nozzle 31.

  The nozzles 29 a and 29 b of the rail elements 18 a and 18 b are flat jet nozzles having an angle of

defined diffusion.

  The height of the ramps above the worksite floor is adjusted by hydraulic cylinders so that the successive jets 33 a and 33 b overlap

  exactly at the ground level of the site In this way

  re, each of the jets 33 a and each of the jets 33 b ensure the spread of the bituminous emulsion over a strip of constant width, the different juxtaposed strips ensuring the formation of a homogeneous layer over all

  the working width of the machine.

  Each of the ramp elements 18 a and 18 b is

  supplied with bituminous emulsion by a volumetric pump-

  stick, from the bituminous emulsion tank 13 which is heat-insulated and which is provided with a temperature maintaining beam in which a heat transfer fluid circulates. The pressure and the feed rate of the boom are adjusted, according to the width and the spreading speed of the paver, by a computer ensuring the control and management of the main functions of the paver. the ramp, the height of it is

  automatically adjusted by the on-board computer.

  In addition, the computer controls the spreading ramps of the emulsion so that the quantity of emulsion spread per unit area is constant, regardless of the speed of advance of the

  spreading device and width.

  The flat jet nozzles 29 a and 29 b are equipped

  for their opening and closing of valves

electropneumatic control.

  In order to obtain a perfectly homogeneous layer

  ne and regular over the entire working width, it is necessary to ensure the closing of certain flat jet nozzles when the two ramp elements come in

  overlapping position on part of their length

  when adjusting the width of the finisher, such as

shown in figure 2.

  As can be seen in FIG. 2, the nozzles 29 b of the rail element 18 b located in the part of this rail element 18 b placed opposite

  of the ramp element 18 a are closed while the

  seems nozzles 29 a of the ramp element 18 a are open so as to allow the formation of flat jets 33 a juxtaposed over the entire length of the ramp 18 a The adjustment of the working width of the finisher is continuous, the position relative of the ramp elements 18 a and 18 b can be arbitrary at a given instant. It therefore generally exists between the last flat jet 33 'a situated at the end of the ramp 18 a and the last flat jet 33 b dispensed by the ramp element 18 b, a longitudinal space 35 the width of which can be between O and d, d being the length of the step, that is to say the longitudinal distance between two nozzles

  any of the ramp elements 18 a and 18 b.

  In order to spread a completely homogeneous and even layer of bituminous emulsion over the entire working width of the paver, it is

  necessary to ensure full spreading and dosing

  bitumen in zone 35.

  For this, use the nozzle 31 located on the extension 30 placed at the end of the ramp element 18 a, this extension 30 of the ramp element 18 a

  being supplied with bituminous emulsion at the same pressure

  sion and at the same flow rate as the boom 18 a.

  In Figure 4, there is shown in section and on a large scale the nozzle 31 disposed at the end of

  the ramp element 18 a and making it possible to ensure the spreading

  biting and metering of bitumen in the interface area

  between the ramp elements 18 a and 18 b.

  The nozzle 31 of cylindrical shape comprises a chamber 32 communicating with the extension 30 of the ramp element 18 a, having a cross section of suitable shape; an adjustment cam 36 is rotatably mounted in the chamber 32, as indicated by the arrow 37. The cam 36 is movable between a completely closed position of the chamber 32, this position corresponding to the outline in solid lines of the chamber

  32 shown in FIG. 4 and an open position

  adjustable ture shown in broken lines.

  The open position of the cam 36 which is adjusted and managed by the finisher's on-board computer, as a function of the relative position of the ramp elements 18 a and 18 b makes it possible to adjust the flow rate and the angle of diffusion of a flat jet 38 ensuring the spreading and

  dosage of bituminous emulsion in the inter-

  face between the ramp elements 18 a and 18 b.

  This adjustment of the cam 36 ensures spreading by the flat jet 38 of a layer of bituminous emulsion, along a strip of desired width, so as to ensure complete continuity of the layer of bituminous emulsion, according to all the width of

  while the paver is moving.

  In FIG. 5, a variant has been represented.

  of means for ensuring the conti-

  nakedness of the emulsion layer, in the interface zone

  between the ramp elements 18 a and 18 b.

  According to this variant, a pneumatically controlled piston 40 is fixed to the end of the ramp element 18 a so as to ensure the displacement of a flat jet nozzle 42 in the interface zone 35 The nozzle 42 is fixed at the end of a conduit 41 connected to the rod

  pneumatic cylinder 40 and supplied with bituminous emulsion

  through the ramp element 18 a.

  The nozzle 42 ensures the formation of a flat jet 43 along a plane perpendicular to the direction of the ramps 18 a and 18 b which corresponds to the direction of movement of the rod of the jack 40, of the conduit 41 and of

  the nozzle 42, as represented by the double arrow 44.

  The pneumatic cylinder 40 ensures the displacement of the nozzle 42 in the zone 35 corresponding to the interface zone between the ramp elements 18 a and 18 b situated between the last jet 33 'a of the ramp 18 a and the

last throw 33 b of the ramp 18 b.

  The nozzle 42 is supplied with bituminous emulsion.

  neuse, via the conduit 41, intermittently, during the displacement of the nozzle 42 in one direction or the other, as shown by the double

arrow 44.

  Intermittent nozzle 42 supply

  allows to realize strip by strip, in the area of the

  terface 35, a layer of bituminous emulsion perfectly continuous and perfectly homogeneous compared to the layers spread by the nozzles 29 a and 29 b of the elements

  of ramp 18 a and 18 b respectively.

  The displacement of the nozzle 42 thanks to the jack

  pneumatic 40 and the opening and closing control

  ture of the nozzle 42 at determined times making it possible to define successive spreading phases separated by phases where the nozzle 42 is not in service, are provided by the on-board computer of the finisher, as a function of the relative position of the elements ramp

18 a and 18 b.

  In FIG. 3, the spreading ramp 18

  of bituminous emulsion has been shown in its posi-

  maximum extension, the ramp elements 18 a and

  18 b then not comprising facing zones.

  The device according to the invention constituting a paver paver with integrated ramp has

  could be made in such a way that it has dimensions

* sions and characteristics to facilitate its conditions of transport from one site to another and its conditions of use on a road or motorway site. The paver has a width of 2.50 m, an overall length of 6.90 m and a height when

of its transfer, 3 m.

  The capacity of the receiving hopper

  bés 8 is 6.5 m 3 and the capacity of the reserve

emulsion of 3000 liters.

  The finishing table to which are associated

  The emulsion spreading ramps and the hot asphalt spreading screws allow to obtain a continuously variable working width between 2.50 m and 4.80 m. The use of extensions, as shown in

  Figure 3, provides a wide working width

  laughing continuously between 3.70 and 6 meters. In all cases, the bitumen emulsion layer

  miner spread on the road surface to be coated is perfectly homogeneous and the hot mixes are spread on this layer of bituminous emulsion as soon as it is spread on the road surface, so that no deterioration of the

  bituminous emulsion layer by an external agent.

  All operations are managed by the on-board computer, according to input data relating to the characteristics of the bonding layer.

  and the covering layer which is used to spread

age and finishing.

  The device according to the invention therefore makes it possible to obtain a bonding layer and a coating layer of perfect quality and the operation of the machine is reduced to simple visual piloting operations which are facilitated by the position of the station. of

  pipe to the upper part of the finisher.

  The invention is not limited to the modes of

  which have been described.

  This is how an emulsion spreading ramp can be used, the movable elements of which are mounted on the finisher in a manner different from

  that which has been described and for example, in an all-

  completely independent of the finishing table.

  The spreading ramp can be produced in a form different from that which has been described and

  equipped with nozzles other than flat jet nozzles.

  Likewise, the means for metering and spreading bituminous emulsion in the interface zone of the ramp can be produced in a form different from the

  two embodiments which have been described.

  In all cases, however, the emulsion spreading ramp must be placed immediately in front of the hot mix spreading device, which can be made in a different form from a screw.

  comprising two parts with opposite steps.

  Generally, the emulsion spreading is carried out in an area located a few centimeters from

  the area where hot mixes are spread.

  In order to keep the advantages of the

  tif according to the invention with regard to its size -

  longitudinal and the quality of realization of the coating

  The distance between the spreading ramp and the hot mix spreader, in the

  longitudinal direction, should not exceed one meter.

  The feed speed of the paver in function-

  road works can generally be

  set to a value between O and 30 m / min.

  Finally, the device according to the invention can be used for the production of any coating.

  road consisting of bituminous products incorporated

  rant a granular material implemented hot and spread on a bonding layer constituted by a

liquid bituminous product.

Claims (13)

  1. Device for producing a road surface by successive spreading on the road surface (2) to be covered, with a bonding layer consisting of a liquid bituminous product, such as a bitumen emulsion, and a layer of hot bituminous material incorporating aggregates such as a mix, constituted by a mobile motorized assembly (1) comprising, from the front to the rear in its direction of movement on   the road surface, a means (8) for receiving the material   granular bituminous stream, a device (12) for transferring the granular bituminous material to the rear of the mobile assembly (1), a device (16) for spreading the granular bituminous material and a compacting and smoothing table (17) of the layer of granular bituminous material as well as a spreading ramp (18) of bituminous product extending in the direction   transverse, supplied by a reservoir (13) of capacity   sufficient tee containing a liquid such as an emulsion,   characterized by the fact that the spreading ramp extends   sible (18) consisting of two ramp elements (18 a,   18 b) relative displacement in the transverse direction   the is arranged, at the rear part of the mobile assembly (1), in front of the bituminous product spreading device (16), with a spacing of less than one meter relative to the spreading device (16), and that it comprises an additional means (30, 31, 40, 41, 42) for spreading and metering bituminous liquid in the interface zone (35) between the two ramp elements (18 a, 18 b) in order to allow adjustment continuously working width.   2. Device according to claim 1, characterized in that each of the elements (18 a, 18 b) of the extendable ramp (18) is fixed to a side door (28 b, 28 c) integral with a table lateral extension (17 b, 17 c) of the compacting and finishing table (17) and that the lateral extension can be performed continuously.   3. Device according to any one of   Claims 1 and 2, characterized in that   each of the ramp elements (18 a, 18 b) comprises a plurality of spreading nozzles (29 a, 29 b) with flat jet distributed along the length of the ramp elements   (18 a, 18 b) with constant spacing (d).   4 Device according to claim 3, characterized in that each of the flat jet nozzles (29 a, 29 b) comprises an opening and closing means pneumatically operated.   5. Device according to any one of   Claims 1 to 4, characterized in that the   additional means for spreading and dosing liquids   bituminous in the interface zone (35) between the two ramp elements (18 a, 18 b) is constituted by a conduit (30) connected to the end of one of the ramp elements (18 a, 18 b ) facing the interior of the finisher,   on which is placed a spreading nozzle (31) comprising   as a chamber (32) communicating with the conduit (30), in which is rotatably mounted a cam (36) for adjusting the flow rate and the angle of dispersion of the jet of bituminous liquid (38) leaving the chamber (32) of the nozzle (31).   6. Device according to any one of   Claims 1 to 4, characterized in that the   additional means for spreading and dosing liquids   bituminous in the interface zone (35) between the two ramp elements (18 a, 18 b) is constituted by a jack (40) fixed to the end of one of the ramp elements (18 a, 18 b) directed towards the interior of the finisher, by a conduit (41) communicating with the ramp element   correspondent (18 a, 18 b) for its liquid supply   bituminous and fixed on the cylinder rod (40) and by a nozzle (42) fixed on the conduit (41) and supplied with bituminous liquid by this conduit (41), the nozzle (42) being a flat jet nozzle ( 43) directed along a plane perpendicular to the longitudinal direction of the elements   ramp elements (18 a, 18 b) and in the direction of travel   ment (44) of the cylinder rod (40) allowing movement   cer the nozzle (42) in the interface zone (35) between the   two ramp elements (18 a, 18 b).   7 Device according to claim 6, characterized in that the nozzle (42) comprises a   opening and closing means allowing the consti-   tution or intermittent interruption of the flat jet (43), during movements of the nozzle (42) in the area interface (35).   8. Device according to any one of   claims 5, 6 and 7, characterized in that the   additional means for spreading and dosing liquids   bituminous (30, 31, 40, 41, 42) is connected, for its order, according to the relative arrangement of   ramp elements (18 a, 18 b), to a pilo calculator tage of the device.   9. Device according to any one of   Claims 1 to 8, characterized in that the   device (16) for spreading granular bituminous material consists of a screw comprising at least   two parts (16 a, 16 b) having opposite steps.   10. Device according to any one of   Claims 1 to 9, characterized in that the   bituminous liquid tank (13) ensuring the supply   tation of the ramp (18) is placed in a vertical position, above the transfer device   bituminous material (12), at the rear of the receiving means tion (8) of bituminous material.   11. Device according to any one of   Claims 1 to 10, characterized in that the   spreading ramp (18) is arranged at the rear of displacement means (4) of the mobile assembly on the road surface (2), below the rear part of the   bituminous material transfer device (12).   12. Device according to any one of   Claims 1 to 11, characterized in that it   comprises means for adjusting the flow rate of the boom (18) making it possible to keep the quantity of product constant   liquid bituminous spread per unit area, whatever   whatever the speed of advancement of the device and the width of the spread.   13. Device according to any one of   Claims 1 to 12, characterized in that it   includes automatic height adjustment means   spreading ramp (18) above the road surface (2) allowing the thickness of the bonding layer to be kept constant over the entire   working width whatever the feed pressure ramp.