Device for paving roadways

The invention relates to a device for processing Of roadways according to the preamble of claim 1.

Such devices are used, for example, in recycling machines For road construction. A road building machine, In which the invention is applied Can be described, for example, in WO-A-96/24725.

A device for producing foam bitumen for road construction machines, With at least one expansion chamber Comprising mixing means, in which hot bitumen At a temperature of 180 ° C and water via injectors Under pressure, is known from WO-A-95/22661 known. The device has a heatable Foam reactor and heatable supply and distribution lines , The lines being additionally insulated can. A plurality of nozzles are arranged along a manifold Are arranged one on top of the other. This distribution line is connected via A line network is connected to a central foam reactor, In which the bitumen foam is produced for all nozzles becomes. In this foam reactor is also a stirrer Respectively. In the known device, That the bitumen foam is a long way from the Expansion chamber as far as the nozzles. This Has the effect that the foam is on its way to the nozzles Partly disintegrates, so that further accurate dosage Of the foam bitumen is not possible. Another Problem Is that the known device is only partially Is heated, and that the nozzles, in particular Heated. As a result, the purification of the System requires a considerable amount of time. As the cleaning With diesel fuel, is also created Still a disposal problem with regard to the polluted Fuel

The object of the invention is to provide a device For processing roadways With which an exact dosage of the Foam bitumen is possible, and with which the cleaning- And maintenance effort is reduced to a minimum.

The features of the claim serve to achieve this object 1.

The invention provides, advantageously, that, A device for processing roadways Process for producing foamed bitumen with several juxtaposes Arranged mixing devices with Foam discharge nozzles are arranged on the hood of the work roll , So that the air emerging from the foam discharge nozzles Foam bitumen spray jet into the working chamber Of the working roll and extending into the direction indicated by the Working roll. The Hot bitumen is fed from a bitumen tank via feed lines And a bitumen injection nozzle with a water tank Through a water injector In an expansion chamber of the mixing device.

Injection of the bitumen foam directly into the working chamber The working roll has the advantage that the foam bitumen Directly into the granulated building material mixture Can be mixed in before the foam collapses into itself. In this case, the foam bitumen is only released shortly before exit From the foam discharge nozzles in an expansion chamber One provided separately for each foam discharge nozzle Mixing means. The production of the Foam bitumen only shortly before leaving the Foam discharge nozzles advantageously make it possible The foam bitumen exactly doses.

In the apparatus for producing foamed bitumen, Is advantageously provided for the injection nozzle for Hot bitumen has a ram adapted to the nozzle cross-section For the nozzle opening leading to the periodic Clean or close the nozzle orifice via a Control is drivable. The plunger is used for nozzle cleaning 1 to 2 times per minute through the nozzle, So that the nozzle cross-section is always kept clear. If the nozzle is to be closed, the plunger remains in the Nozzle cross-section. Each nozzle can be individually controlled, so That the working width, for example, in the case of several passes over a Road is selectable.

It is further characterized in a device for generating Foam bitumen is provided, that a microprocessor control The streams of hot bitumen and water in Dependence of the speed of propulsion of the road construction machine . This ensures that The dosage with high accuracy and driving speed-dependent And that the ratio of foam bitumen And granulated building material Is.

In a preferred exemplary embodiment, Characterized in that the water tank is arranged on the landing gear. On On the running gear has the advantage, That no separate water supply is required. The Water in the water tank can also be used for Other tasks, eg for soil humidification during compaction Of a roadway.

Preferably, it is provided that in the expansion chamber Air can be injected into each mixing device. The additional injection of air intensifies the foam formation And allows expansion of the foam bitumen To about 20 times the original volume. A Advantageous further development provides that laterally, The working roll is protruding one manually manually Mixing device with foam outlet nozzle Is. This additionally provided foam discharge nozzle Serves at the beginning or during the operation of the Road machine to check the foam quality.

The expansion chamber is preferably in cross-section Circular, the bitumen injection nozzle being coaxial with Of the expansion chamber. The injection Injection devices for the water and / or air nozzles Water or air radially or tangentially into the outlet Of the bitumen injection nozzle Bitumens. This creates a strong turbulence In the expansion chamber, with which an optimal Foam quality can be produced.

It is preferably provided that the expansion chamber has a Eccentrically arranged foam discharge nozzle. Such an eccentrically arranged nozzle reinforces the nozzle Swirls the foam bitumen and allows a higher Expansion number for a longer half - life of the Foam

The mixing devices are heatable. The heating is done By means of thermostat-controlled heating devices, The optimum operating temperature before start and during Of the stake, even in case of interruption. A complicated rinsing of the mixing devices with The foam discharge nozzles can be omitted at the working end.

The generator for generating the heating current already generates The full heating voltage in the idle state of the drive motor And also keeps it at higher rotational speeds of the drive motor constant.

For this purpose, the generator has a hydraulic drive , Which can be adjusted to a constant value by means of a flow control valve Drive speed can be set.

Further advantageous features are the further subclaims refer to.

In the following, reference is made to the drawings An embodiment of the invention is explained in more detail.

Show it:<dl tsize="6" compact="compact"><dt>FIG</dt><dd>A road construction machine,</dd><dt>FIG</dt><dd>4 is a schematic representation of the microprocessor control For the foam generation process,</dd><dt>FIG</dt><dd>A flow chart of the foam bitum components,</dd><dt>FIG</dt><dd>The tappet control, and</dd><dt>FIG</dt><dd>A mixing device.</dd></dl>

FIG. 1 shows the device for processing roadways With a machine frame supported by two undercarriages 2 1 and one of a driver's cab 3 Driving range.

The landing gear 2 has at the front and rear end of the Machine frame 1 two together or alternatively individually Steerable chassis axles.

Below the machine frame 1 is a work roll 4 Is arranged under a hood 8 which surrounds the working chamber 6 Of the work roll 4 upwards and to the sides.

The hood 8, which is connected to the machine frame 1, A shaft parallel to the roller axis of the work roll 4 Pivotable breaker bars 19. A detailed Description of the road construction machine shown in FIG See WO-A-96/24725.

The hood 8 has a device at its upper portion 10 for producing foamed bitumen. For the production Of foam bitumen becomes about 180 ° C hot bitumen Mixed with cold water. As a result, the bitumen foams , The original volume of the components being By about 20 times.

By the foaming process, which assists with blowing in air Can be the viscosity of the bitumen Greatly reduced. The bitumen foam can be formed by Of a greatly increased volume over several parallel To the axis of the working roll 4 14 uniformly into the working chamber 6 and Thereby mixing into the granulated mixture of building materials.

The device 10 for producing foam bitumen consists In particular from, for example, 16 arranged side by side Mixing means 12 which are connected to one another with a Common supply line 16, 42 for hot bitumen are. The mixing devices 12 have a bitumen injection nozzle 18, which in the opened state have a bitumen free-wheel Into an expansion chamber 26. Orthogonal to this free beam become radial or tangential To the circular expansion chamber in the cross-section 26 water via a water injection nozzle 22 and Air via an air injection device 24. In The expansion chamber becomes a strong swirling Of the expanding foam volume, whereby A high expansion number of the foam bitumen and a Longer half-life. The air will For example under a pressure of 4 to 5 bar.

The foam discharge nozzle 14 is eccentric to the expansion chamber 26 and to the bitumen injection nozzle 18, Thereby preventing the swirling in the expansion chamber 26 Is strengthened.

The bitumen injection nozzle is pulsed clocked with help Of a plunger 30 is periodically cleaned, the plunger Controlled by a pneumatic drive device 32 Is driven. The plunger 30 can also be Can be used to close the bitumen injection nozzle 18, For example, the foam bitumen in a Reduced width. This is For example in the case of multi-lane, overlapping work Useful

FIG. 2 is a schematic representation of the microprocessor control For the control of the foaming process and The amount of dosing, and the dosage of the foam bitumen.

The microprocessor 36 is connected to an electronic input / output unit 38 is connected to a display 39. At Of the input / output unit 38 may be the bitument input in % By weight and the water addition for the foaming process in% Of the bitumen quantity. Furthermore, the Spray width for overlapping work, That is, individual foam discharge nozzles 14 can be arranged Desire to be turned off. All operating and working data Are displayed on the display 39. The microprocessor 36 is further connected to a printer 40, Data for documentation purposes. About a Wheel sensor 41, the microprocessor 36 receives a feed rate The engine speed signal, So that the dosage of the foam bitumen components Depending on the driving speed Respectively. The microprocessor 36 generates Control signal for the drive motors 21, 23 for the bitumen suction pump For bitumen 20, as well as the water suction pump 24. The effective amounts of bitumen and water Are supplied from the pumps 20 and 24 to the microprocessor For the purpose of regulation.

The pulse-clocked line 28 is also fed to the pulse line Nozzle cleaning in each mixing device 12.

In addition to the device for producing foam bitumen As shown in FIG. 2, a device for the Feeding of a water-cement suspension 46 is provided Parallel to the means for generating Foam bitumen 10 can be arranged on the hood 8. about A signal line 48 is supplied to the drive motor 50 of a Suction pump 52 of the injection device for the water-cement suspension 46.

FIG. 3 illustrates the combination of bitumen, water And air in the mixing means 12. The connecting part 19 for the hot bitumen feed receives hot bitumen Of the bitumen tank arranged on the chassis 2. The Pump 20 for bitumen is, as already mentioned in FIG The microprocessor 36. A temperature sensor 23 Monitors the temperature of the Hot bitumen. This becomes hot in a bitumen filter 25 Bitumen. Behind the bitumen filter 25 is a Pressure sensor 27, which monitors the operating pressure. The feed line 16 opens into a distributor line 42, which can also be executed as a ringing line, So that unnecessary bitumen is recirculated into the bitumen tank Is.

Via the water pump 24, the water from one on the (2) is fed by means of a Water supply line 43 and a respective water valve 45 for two mixing devices 12 the water to the water injectors 22. It may be provided that In each case one water valve 45, two non-adjacent mixing Devices 12.

Compressed air is supplied via a compressor 28 via an air supply line 44 and air injectors 24 under one Pressure of, for example, 4 to 5 bar.

With lateral spacing from the, for example, 16 side by side Along the distributor / pipe 42 for hot Bitumen mixing devices 12 can be a separate Mixing means 12 may be arranged such that It laterally protrudes via the working roll 4. These Further mixing means is used as a test nozzle At the beginning or during the operation a quality check With respect to the foam quality. This test nozzle can be controlled manually.

From the same air compressor 28 or a separate air compressor Compressor is also compressed air for cleaning Of the bitumen injection nozzle. The compressed air becomes Via pneumatic valves 33 to the pneumatic drive devices 32 for the tappets 30. In the process, Same stroke also the bitumen injection nozzle 18 of the test nozzle cleaned.

The bitumen suction pump 20, the feed lines 16, and The distribution and ring line 42, as well as the mixing devices Itself, in particular the bitumen injection nozzle 18 Are provided with heating elements and temperature sensors. The temperature sensors give a temperature signal to the Microprocessor 36 or to a thermostat control. The Suction pump for bitumen, supply lines 16, 42, as well as The mixing devices 12 are also insulated thickwalled, To reduce heat loss and compliance Of the optimum processing temperature.

A power generator is powered by a hydraulic motor driven. The hydromotor for the generator gets its Driving energy from a hydropump connected to the Combustion engine of the road-building machine. The hydromotor for the current generator already generates in the Idling operation of the internal combustion engine one for the heating Of the device 10 for producing foam bitumen Necessary energy.

With the help of a flow control valve the speed of the Hydromotors are kept constant for the current generator.

The microprocessor-controlled device 10 for generating Of foam bitumen allows the operation of all functions And the preselection of the train quantities for hot bitumen, water And air, as well as the work - related parameters of the Driving position 3 off.

The microprocessor control also allows control Of the load quantities proportional to the propulsion speed.

The exact temperature control in conjunction with the periodic Cleaning of the bitumen injection nozzles High dosing accuracy and functional safety. On Complex rinsing of the device 10 for producing Foam bitumen can be dispensed with at the working site.