ROAD PAVER WITH SPRAYING DEVICE

Abstract

The disclosure relates to a road paver that comprises a tractor with a material hopper and a machine frame. The machine frame is pivotably connected to the paving screed by pulling arms and a material spreading auger is disposed in a gap between the tractor and the paving screed. A longitudinal conveyor device extends through a tunnel between the material hopper and the gap. The road paver according to the disclosure is characterized by a spraying device that is configured for injecting a liquid into the gap between the tractor and the paving screed or into the tunnel or into the material hopper.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims foreign priority benefits under 35 U.S.C. § 119(a)-(d) to European patent application number EP 16187612.3, filed Sep. 7, 2016, which is incorporated by reference in its entirety.

TECHNICAL FIELD

The disclosure relates to a road paver.

BACKGROUND

Road pavers are mostly used in road construction. There, they are used for spreading, smoothing and compacting of different types of bulk material. The bulk material can for example be asphalt mixtures. But materials, which are used for the substructure that carries the different asphalt layers of a road, can also be spread, smoothed and compacted by road pavers.

In some cases, the substructure is moistened from above by means of tank vehicles with sprinkling systems after preparation by a road paver or a grader. Therefore, the substructure has to be accessed by these vehicles. Compacting by means of rollers can take place afterwards. As the substructure materials are often loose bulk materials, i.e., without the addition of binding agents, driving on the substructure has negative consequences for the surface quality of the substructure and hence for the quality and stability of the future road.

SUMMARY

A purpose of embodiments according to the disclosure is to improve the surface quality of substructure layers in road construction.

A road paver according to the disclosure comprises a tractor with a material hopper and a machine frame, wherein the machine frame is pivotably connected to a paving screed by pulling arms. A material spreading auger is disposed in a gap between the tractor and the paving screed. A longitudinal conveyor device extends through a tunnel between the material hopper and the gap. The road paver according to the disclosure is characterized by a spraying device that is installed for spraying a liquid into the gap between the tractor and the paving screed or into the tunnel or into the material hopper. Therefore, the substructure bulk material can be moistened prior to smoothing and, where applicable, compacting so that—possibly with the exception of the final compacting roller vehicles—no further vehicles have to drive over the installed substructure. Additional advantages of spraying into the gap between the tractor and the paving screed consist in the liquid being mixed with the paving material, which ensures a more homogeneous water distribution in the substructure. In addition, swirling of dust is reduced. In connection with the present disclosure, spraying and/or injection shall be understood as spreading a liquid. In this process, vaporization or fogging can take place. However, this is not required for implementing the disclosure. A spraying and/or injection process in the sense of the present disclosure can also mean, for example, that the liquid flows out of a tube end. The liquid can for example be water.

It is advantageous for the spraying device to be disposed in the gap. This way, the path that the liquid has to travel from the spraying device to the destination can be reduced and liquid losses, e.g., through evaporation, can be avoided.

It is possible for the spraying device to be fastened on the machine frame or on the paving screed. However, it is equally conceivable for the spraying device to be fastened on at least one of the pulling arms or on a fastening device that is disposed for connecting the paving screed to the pulling arms.

It is expedient for the spraying device to have one or several outlet devices where the liquid selectively flows out. In particular, if there are multiple outlet devices, it can be advantageous to let the liquid flow out on only one or multiple ones of the outlet devices as required. In particular, the direction and the quantity of the liquid that flows out per time unit can be adjustable as will be described in greater detail in the following.

It is particularly advantageous if the outlet devices have respectively one adjusting element that is configured for variable adjustment of a liquid flow out of the respective outlet device. This way, the liquid flow and/or the liquid flows can be adapted even more accurately to the requirement. The adjusting elements can be operable manually or automatically. Mechanical or electrical actuation can be provided. In addition, the adjusting elements can be remote-controlled and/or operable directly on the adjusting element. The adjusting element and/or the adjusting elements can for example be one or multiple ball valves. The outlet devices can have for example one or multiple spraying nozzles, tongue-type nozzles or vaporization devices. However, also one or multiple tube ends is/are conceivable.

The spraying device can preferably have one or multiple coupling devices. For example, two coupling devices can be disposed on opposite sections of the spraying device.

It is possible that an inflow device is disposed on the spraying device. Said inflow device can enable and/or facilitate supply of the spraying device with liquid. For this purpose, the inflow device can be connected to the spraying device for example through the coupling device and/or one of the coupling devices. The inflow device can comprise for example a supply line. The inflow device can extend from the spraying device to a different location of the road paver and therefore facilitate the connection of the spraying device to a liquid supply such as a hydrant, a tank truck or a liquid supply carried along by the road paver or an on-board liquid reservoir.

It is advantageous for the inflow device to be fastened detachably on the spraying device. Therefore, it can be decided situationally if and/or where the inflow device is required or useful, and it is possible that the liquid supply is connected directly, i.e., without using an inflow device, to the spraying device, for example via the coupling device.

It is particularly advantageous if an adjusting unit for variable adjustment of a liquid flow to the spraying device is provided. This can enable an adjustment of the liquid flow to the spraying device up to a complete switch-off. This can be advantageous in relation to an individual adjustment at the outlet device. The adjusting unit can for example be a valve or a flow controller. An adjusting unit can be provided alternatively or in addition to the adjusting element(s).

Different variants of arranging the adjusting unit are possible. For example, it is conceivable for the adjusting unit to be disposed on the inflow device and/or on the spraying device. An arrangement on the inflow device and the spraying device can for example exist if the adjusting unit is provided between the two. The adjusting unit can be disposed for example on an end section of the inflow device that faces away from the spraying device or on the end section of the inflow device that faces the spraying device.

Advantageously, the adjusting unit can be controlled electronically. This way, activation, deactivation or adjustment of the liquid flow can occur automatically and depending on different parameters. Examples for such parameters are for example the actuation of a driving main switch, the velocity of different conveyor devices of the road paver such as the material spreading auger or of so-called scraper belts that may be provided, or the state of different material quantity sensors such as ultrasound or paddle sensors. In addition, or as an alternative to an electronic control, also a hydraulic or pneumatic control of the adjusting unit is conceivable. These may enable or facilitate the automation explained above as well.

In a further variant, the adjusting unit can have an adjustable flow controller for adjusting the liquid flow.

Regardless of the control of the adjusting unit, it is advantageous in addition for the adjusting elements to be controllable in an electronic way. Therefore, activation, deactivation or adjustment of the liquid flow can occur automatically and depending on different parameters. Examples for such parameters are the operation of a driving main switch, the velocity of different conveyor devices of the road paver, e.g., the material spreading auger or so-called scraper belts that may be provided, or the state of different material quantity sensors such as ultrasound or paddle sensors. In addition, or as an alternative to an electric control, also a hydraulic or pneumatic control of the adjusting element(s) is conceivable. These may enable or facilitate the automation explained above as well.

In a further variant, the adjusting element(s) can have an adjustable flow controller for adjusting the liquid flow.

It is conceivable for the spraying device to be disposed between two of the pulling arms. Such an arrangement is in particular advantageous for rigid, non-extended paving screeds. In extending screeds or screeds that are widened by rigid widening parts, widening units can be mountable on the spraying device, in particular by one or multiple ones of the previously mentioned coupling devices. Said widening units can have one or multiple further outlet devices that may correspond to the ones of the spraying device. It is conceivable for the widening units to be not disposed between two pulling arms, but only next to one of said pulling arms. It is also possible that the widening units extend laterally beyond the width of the tractor. It is advantageous for the widening units to have a variable width, e.g., by extending devices.

The disclosure relates to a road paver of the previously described type. In the following, an embodiment will be explained in greater detail by means of drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a conventional road paver;

FIG. 2 shows a detail view of parts of the road paver according to the disclosure with a spraying device;

FIG. 3 shows a perspective view of a spraying device according to the disclosure according to a first embodiment;

FIG. 4 shows a perspective view of a spraying device according to the disclosure according to a second embodiment;

FIG. 5 shows a schematic display of different components that can be provided for open-and/or closed-loop control of an amount of liquid spread by the spraying device;

FIG. 6 shows a perspective view of a road paver according to the disclosure according to a further embodiment; and

FIG. 7 shows a detail view of parts of a road paver according to the disclosure with a spraying device according to a further embodiment.

DETAILED DESCRIPTION

As required, detailed embodiments are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary and that various and alternative forms may be employed. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art.

FIG. 1 shows a road paver 1 as known from the state of the art. It comprises a tractor 2 and a paving screed 3 that is disposed behind said tractor in the direction of travel. The tractor 2 comprises a machine frame 4 and a material hopper 5 that can be fastened on the machine frame 4. In the area of the material hopper 5, a longitudinal conveyor device, which can comprise for example one or two scraper belts 22, is provided. The longitudinal conveyor device extends through a tunnel 26 between the material hopper 5 and the gap 7. The paving screed 3 is pivotably installed on the machine frame 4 by pulling arms 6. A gap 7 is provided between the tractor 2 and the paving screed 3. For the sake of simplicity, the previously used reference signs for the respective components will be used further for the description of a road paver according to the disclosure in the following.

FIG. 2 shows a detail view that illustrates only selected components of a road paver 1 according to the disclosure for a better overview. Out of the previously mentioned components, in particular the pulling arms 6 are visible. Moreover, the gap 7, which is provided between the tractor 2 and the paving screed 3, can be seen. Thanks to the display of only selected components, it can now also be seen that a material spreading auger 8 is disposed in the gap 7. Likewise, a fastening device 9, which is installed for connecting the paving screed 3 to the pulling arms 6, can be seen. A spraying device 10 is provided in the present embodiment. Said spraying device can for example be disposed in the gap 7. It is connected to an inflow device 12 through a coupling device 11. A coupling piece 13 is provided on the end section of the inflow device 12 that faces away from the spraying device 10. The coupling piece 13 can be installed for the connection with a liquid supply. The liquid supply can for example be a hydrant, a tank truck or a liquid tank that is carried along on the road paver 1.

FIG. 3 displays the spraying device 10. Now it is apparent that said spraying device has two coupling devices 11a, 11b in the present embodiment. These are disposed on opposite sections of the spraying device 10 in the present embodiment. However, this can be provided differently depending on the installing situation. In the present embodiment, only one inflow device 12, which is connected to a first coupling device 11a, is provided. A second coupling device 11b is closed by a closure 14. Embodiments of the disclosure, in which multiple inflow devices 12 are provided, which can be connected to multiple coupling devices 11, are possible as well.

An adjusting unit 15 is provided in the present embodiment. This adjusting unit 15 can be used to adjust a liquid flow to the spraying device 10 in a variable way. As an example for an arrangement suitable for this purpose, FIG. 3 shows the arrangement of the adjusting unit 15 between the spraying device 10 and the inflow device 12. Alternatively, however, the adjusting unit 15 could also be disposed for example on the end section of the inflow device 12 that faces away from the spraying device 10.

Six outlet devices 16 are provided in the present embodiment. However, this number shall only be regarded as exemplary and can be adapted in a suitable way depending on the purpose of use. For variable adjustment of a liquid flow that flows out of the respective outlet device 16, one adjusting element 17 is provided on each outlet device 16. As indicated in FIG. 3, said adjusting elements can for example be ball valves. In addition, the outlet devices 16 of the described embodiment comprise spreading elements 18. These can be configured to spread the liquid flow that flows out of the respective outlet device 16 and/or to guide said flow in a specific direction. In the illustrated embodiment, tongue-type nozzles are shown in an exemplary way as spreading elements 18 by which both spreading as well as an orientation of the liquid flow can be achieved. However, other spreading elements 18 are also possible, e.g., spraying nozzles, vaporization devices or a simple tube end.

FIG. 4 shows a spraying device 10 according to a further embodiment. A widening unit 19a, 19b is provided on each of the coupling devices 11a and 11b. As shown in FIG. 4, these widening units can each have one furcation 20a, 20b. On a first furcation 20a of a first widening unit 19a, the inflow device 12 can be connected. A second furcation 20b of the second widening unit 19b is closed by means of the closure 14. However, it is also possible that a second inflow device 12 is provided on the second furcation 20b. Outlet devices 16 are also provided on the widening units 19a, 19b. Said outlet devices have the same configuration possibilities as the outlet devices 16 described with reference to the first embodiment. It is conceivable that they have the same configurations as the outlet devices 16 provided on the spraying device 10. Alternatively, it is possible that the outlet devices 16 are configured differently.

Both the adjusting elements 17 as well as the adjusting unit 15 are displayed as simple ball valves in the described embodiments. However, this shall only be understood in an exemplary way. Any devices, which are suitable to variably adjust an amount of liquid that flows through the respective part per time unit, are possible. In particular, valves that are configured to vary a flow cross-section are conceivable. It is for example possible that the adjusting element(s) 17 and/or the adjusting unit(s) 15 each comprise an adjustable flow controller 17a, 15a. In addition, devices for creating a variable pulsed operation, which creates a variable number of spraying pulses per time unit, or devices for changing the pressure in the respective tube are possible.

An adjustment of the amount of liquid per time unit can occur for example mechanically, electromechanically, hydraulically or pneumatically. It is further conceivable that the adjustment can be effected on the respective adjusting element 17 and/or the adjusting unit 15. In addition, or as an alternative, a remote actuation can be provided. An electromechanical, hydraulic or pneumatic actuation that can be triggered and/or implemented remotely by a control unit 21 (see FIG. 5) is particularly advantageous. The control device 21 can in this context be an electronic, a hydraulic or pneumatic control device. It can comprise a closed control loop or an open control path.

The actuation can occur in an automated way depending on different parameters of the road paver, e.g., of the actuation of a driving main switch 23, a velocity of different conveyor devices of the road paver 1, for example of the material spreading auger 8 or the scraper belts 22, or one or multiple output signal(s) of one or multiple material quantity sensor(s) 24 (see FIG. 5) that can be provided for detecting different material amounts at different locations in or on the road paver 1.

FIG. 5 is an exemplary schematic representation of a possible embodiment of the actuation of the adjusting element(s) 17 and/or the adjusting unit(s) 15. Inputs 25 are taken into account during actuation of the adjusting element(s) 17 and/or the adjusting unit(s) 15. Inputs 25 shall be understood as parameters that can be taken into account for an automated actuation of the adjusting element(s) 17 and/or the adjusting unit(s) 15; the ones mentioned in the previous section are illustrated exemplarily in FIG. 5.

It should be clear that not all of the inputs 25 displayed at the top of FIG. 5 have to be implemented. It is also conceivable to consider only one or multiple of these inputs 25 during actuation of the adjusting element(s) 17 and/or the adjusting unit(s) 15. Likewise, it should be clear that, as an alternative, only the adjusting element(s) 17 or only the adjusting unit(s) 15 can be actuated by the control device 21 and/or depending on one or multiple of the inputs 25.

FIG. 6 shows a road paver 1 according to a further embodiment of the disclosure. This road paver has a spraying device 10 that is configured for injecting a liquid into the material hopper 5. It is fastened on the machine frame 4. In this embodiment as well, the spraying device 10 has several outlet devices 16. Said outlet devices have the same configuration possibilities as the outlet devices 16 described with regard to the first and second embodiment.

FIG. 7 shows a detail view of a road paver 1 according to a further embodiment of the disclosure. Dashed lines indicate that a spraying device 10 is disposed within the tunnel 26. This spraying device is configured for injecting liquid into the tunnel 26, in particular on the material that is conveyed through the tunnel 26. In this embodiment as well, the spraying device 10 has several outlet devices 16. These outlet devices have the same configuration possibilities as the outlet devices 16 described with regard to the first and the second embodiment. Alternatively, it is conceivable that the spraying device 10 is disposed outside of the tunnels 26 and configured for injecting liquid into the tunnel.

While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms according to the disclosure. In that regard, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. Additionally, the features of various implementing embodiments may be combined to form further embodiments according to the disclosure.

Claims

1. A road paver comprising:

a tractor including a material hopper and a machine frame;

a paving screed pivotably connected to the machine frame by pulling arms;

a material spreading auger disposed in a gap between the tractor and the paving screed;

a longitudinal conveyor device that extends through a tunnel between the material hopper and the gap; and

a spraying device that is configured for injecting a liquid into the gap between the tractor and the paving screed or into the tunnel or into the material hopper.

2. The road paver according to claim 1 wherein the spraying device is disposed in the gap.

3. The road paver according claim 1 wherein the spraying device is fastened on the machine frame or on the paving screed.

4. The road paver according to claim 1 wherein the spraying device is fastened on at least one of the pulling arms or on a fastening device that is configured to connect the paving screed to the pulling arms.

5. The road paver according to claim 1 wherein the spraying device has one or more outlet devices through which the liquid may selectively flow.

6. The road paver according to claim 5 wherein each of the one or more outlet devices has an adjusting element that is configured for variable adjustment of a liquid flow out of the respective outlet device.

7. The road paver according to claim 5 wherein the one or more outlet devices comprises multiple outlet devices, and wherein an adjusting element is provided, which is configured for variable adjustment of a liquid flow to a group of the outlet devices, wherein the group of outlet devices comprises at least two outlet devices.

8. The road paver according to claim 1 wherein an inflow device is provided on the spraying device.

9. The road paver according to claim 8 wherein the inflow device is fastened detachably on the spraying device.

10. The road paver according to claim 1 further comprising an adjusting unit for variable adjustment of a liquid flow to the spraying device.

11. The road paver according to claim 10 further comprising an inflow device provided on the spraying device, and wherein the adjusting unit is disposed on the inflow device and/or on the spraying device.

12. The road paver according to claim 10 further comprising an inflow device provided on the spraying device, wherein the adjusting unit is disposed between the spraying device and the inflow device.

13. The road paver according to claim 10 wherein the adjusting unit is electronically controllable.

14. The road paver according to claim 10 wherein the adjusting unit has an adjustable flow controller for adjusting the liquid flow.

15. The road paver according to claim 1 wherein the spraying device is arranged between two of the pulling arms.

16. A road paver comprising:

a tractor including a material hopper and a machine frame;

a paving screed pivotally connected to the machine frame;

a material spreading auger disposed in a gap between the tractor and the paving screed;

a longitudinal conveyor device that extends through a tunnel between the material hopper and the gap; and

a spraying device configured to inject a liquid into the gap between the tractor and the paving screed or into the tunnel or into the material hopper.