EP2423384B1 - Spray device for a construction machine for earth works, construction machine with a spray device and method for operating a spray device - Google Patents

Description

The invention relates to a spraying device for a construction machine for soil cultivation, a construction machine with such a spraying device and a method for operating a spraying device.

Many construction machines, in particular construction machines for working floors or roadways, such as a cold milling machine for the milling of road surfaces and floor coverings, a stabilizer for stabilizing non-load-bearing soils and a recycler for repairing repaired road pavements, have Einsprüheinrichtungen to the dust during the To reduce working process and / or the soil material to be processed fluid, especially water, add to obtain desired properties. Usually, such construction machines are provided with a work roll with which the floor or the road can be broken up and / or mixed. For example, if the processing involves an asphalt or concrete pavement, a typical operation is milling the pavement. The work roll is horizontal with respect to its cylinder axis directly or indirectly mounted on a machine frame of the construction machine and extending transversely to the longitudinal direction and working direction of the construction machine. The work roll is also usually stored in a working space open to the floor, in which the work roll rotates in the working insert and comes into contact with the soil to be processed. To the other pages, the work roll is usually shielded, for example by a guard or a Fräswalzenkasten. The closed design of the working space prevents, inter alia, that the material milled off from the work roll rotating about its longitudinal axis is uncontrollably thrown into the surroundings of the construction machine. The work space limited to the outside also serves the transport of material in order to be able to remove material milled off from the milling drum in a controlled manner. In another application The task of the working space is to provide a mixing room in which the processed raw material can be mixed with an additive, for example, to achieve a Bodenbefestigung or stabilization. Typical additives in this context are, for example, hydraulic or bituminous binders or water.

In order to be able to add a fluid in working mode to the working space, the construction machine has a spraying device. Concretely, the spraying device usually comprises a fluid delivery device, via which the fluid can be introduced into the working space. Such a fluid dispensing device may comprise, for example, a valve and an outlet opening or outlet nozzle opening into the working space. Frequently, the part of the fluid delivery device, via which the fluid exits into the working space, is arranged in the interior of the working space. Hereinafter, the term fluid delivery device includes all those means that are available for immediate delivery of the fluid into the working space. This is thus at least a suitable fluid outlet opening, for example an opening of a nozzle. The fluid dispenser also often includes a valve or similar regulating means. This does not necessarily have to form a structural unit with the at least one fluid outlet opening. It is essential that the regulation means can regulate the fluid flow through the outlet opening, for example, release and lock. Further, a conduit system is provided, via which the fluid is passed to the fluid dispenser. The conduit system may optionally include other components, such as one or more pumps via which the fluid is pumped from the reservoir into the conduit system and finally to the at least one exit nozzle, filters, valves, etc. The fluid supply to the construction machine itself is either via one or more several own entrained fluid tanks and / or via a connection of the construction machine with a suitable tanker vehicle. Also, the construction machine can be designed to supply the working space with different fluids or a fluid mixture. For this purpose, for example, several fluid tanks may be integrated in the construction machine or suitable connections for a tanker vehicle may be present.

The amount of fluid or the flow rate of fluid to be added to the soil material to be processed, depending on the application, can vary widely. A generic spraying device therefore further comprises a control unit which controls the fluid supply through the piping system to the fluid delivery device. The control unit thus represents the central control and control component of the spraying device and is responsible for controlling the spraying device or the individual components of the spraying device. The control unit may, for example, specifically be a suitably programmed microcontroller which has suitable Signal connections controls the corresponding components of the sprayer. The control unit may further comprise an input unit via which the machine operator can input control parameters such as, for example, the nature of the ground, the delivery line of the injection device, the type of fluid, etc. Typical control functions, which are controlled by the control unit, are, for example, the switching on and off of the fluid supply or a corresponding pump, the regulation of the fluid pressure or the delivered amount of fluid per unit time that emerges through the fluid dispenser, or the flow rate, the type of the fluid, etc.

A typical application in which the introduction of a fluid into the working space of the construction machine is desired, for example, the blending of the work roll processed material in the working space with water to improve together with previously applied to the soil to be processed binders such as lime Material properties of the soil material to achieve. Alternatively or additionally, by moistening the soil material but also a reduction of dust development in the working mode can be achieved. Other exemplary applications include the incorporation of bituminous binders, the production and introduction of foam bitumen, etc.
However, the required quantities of fluid can vary greatly depending on the conditions of use. In recycling applications, for example, comparatively little water (eg about 100-300 l / min) is often required, whereas in stabilization applications, for example, up to 700-1000 l / min should be conveyed from the spraying device into the working space. In the case of the usual injection devices, therefore, considerable pressure fluctuations or insufficient dosing accuracies and an uneven distribution of the fluid in the working space arise over the entire range of application. In particular, at low pressures, therefore, uneven and therefore unsatisfactory distribution results frequently occur in conventional injection devices. In addition, there is a risk, especially at low pressures, that the fluid delivery device becomes clogged with soil material to be processed and therefore fails for further use.

From the US 2003/0194273 A1 a recycler is known, which provides a fluid delivery device for a milling unit and a further fluid delivery device for a downstream mixing unit. In the prior art are from the US 3,782,634 A and the US 2008/0193215 A1 also known tank vehicles with a spray, with which a liquid can be distributed on the soil surface. The spraying devices may comprise subunits with which an optimized distribution of the liquid on the soil surface in terms of quantity and width is possible.

The object of the invention is therefore to provide a spraying device for a generic construction machine, the uniform introduction of a fluid into the working space over a wide range, ie from small amounts of fluid to relatively high amounts of fluid per time and / or distance, continuously and reliably guaranteed. In addition, the sprayer should be robust and fail-safe.

The solution of the invention is achieved with a spraying device for introducing a fluid into the working space of a construction machine, with a construction machine having such a spraying device and with a method for operating such a spraying device according to the independent claims. Preferred developments are specified in the dependent claims.

According to the invention, it is provided that the spraying device for introducing a fluid into the working space of a construction machine for working floors or roadways has at least one first and at least one second fluid delivery device, via which the fluid can be introduced into the working space. The first fluid delivery device is designed to deliver a larger amount of fluid than the second fluid delivery device at a predetermined operating pressure. The specified operating pressure is thus a certain pressure during operation of the injection device, for example in the line system upstream of the at least first and the at least second fluid delivery device or a specific section in the line system. In this comparison pressure, the at least first and the at least second fluid delivery device deliver different amounts of fluid into the working space. Based on this comparison pressure, the at least first fluid delivery device is thus more efficient than the at least second fluid delivery device and, at the same operating pressure, delivers a larger volume of fluid per unit time into the working space than the at least second fluid delivery device. It goes without saying that the operating pressure relevant here prevails only at those points in the injection device at which the fluid pressure changes depending on the amount of fluid conveyed in the line system or increases with increasing delivery rate and vice versa. For this purpose, use is made in particular of the fluid pressure in the line system between the pump and the at least first and the at least second fluid delivery device. Essential for the inventive design of the sprayer is thus that the sprayer has at least two fluid dispensers, which differ in their performance from each other. The "large" fluid delivery device makes it possible at the particular operating pressure, for example at a bar, to deliver a significantly larger volume of fluid into the working space than the "smaller" second fluid delivery device at precisely this operating pressure. It goes without saying that both fluid dispensers deliver more fluid into the working space as the operating pressure is increased. However, a larger volume always flows at comparable operating pressure through the larger first fluid delivery device. In other words, the sprayer according to the invention thus comprises a "high performance fluid delivery device" for delivering large volumes of fluid per unit time to the working space and a "low power fluid delivery device" as compared to the high performance fluid delivery device lower fluid deliveries per unit time into the workspace. This can be reliably covered in a smaller range of operating pressure, a particularly wide range or a particularly wide range of metered into the working space fluid volume per unit time. If it is necessary to introduce only a small amount of fluid, the introduction of the fluid into the working space preferably takes place via the second fluid delivery device and with an increased fluid requirement via the first fluid delivery device or even via the at least two fluid delivery devices. Characterized in that the first fluid dispensing device is designed in such a way that it emits a larger amount of fluid than the second fluid dispensing device at a predetermined operating pressure, the sprayer can bring in a comparatively narrow operating pressure range reliably highly varying fluid volumes homogeneously distributed in the working space.

Another essential component of the injection device according to the invention is the line system, via which the fluid is passed to the at least first and the at least second fluid delivery device. The line system comprises all line parts from the fluid tank or fluid inlet of the construction machine to the respective fluid delivery device. The task of the line system is summarized in passing the fluid from a feed or storage area to the fluid dispenser. Typical components of the conduit system may be, for example, pipelines, hoses, valves, one or more pumps, filter units, line bars, etc.

An essential element of the injection device according to the invention also represents a control unit, which is designed to control the fluid delivery via the at least first and the at least second fluid delivery device. The control unit regulates the fluid delivery of the at least first and at least the second fluid delivery device in such a way that it individually or individually controls the first fluid delivery device and the second fluid delivery device or both, as will be explained in more detail below. Under an individual control is in particular, for example, only a partial activation of one of the at least first or at least second fluid dispensing devices to understand, depending on the embodiment. The control unit thus regulates the at least first and the at least second fluid delivery device independently of each other. Of course, it is also possible that in addition to the at least first and the at least second fluid delivery device further fluid delivery devices are present, which are also controlled separately by the control unit. The control unit can be designed self-regulating. In this embodiment, the operator thus set desired values. Based on these setpoints, the control unit determines and regulates the required Flow rate. Typical parameters that can be taken into account by the control unit are the desired fluid distribution or moisture in the soil material to be processed, the depth of cut, the soil density, the ground speed, etc. If the depth of cut in this embodiment is thus changed during operation, for example increased, increases the control unit at the same time the flow rate fluid or the volume of the introduced into the working space fluid per unit time in a corresponding extent, so that despite different cutting depths, the introduced into the soil amount of fluid per volume of soil material is constant.

Each fluid delivery device comprises at least one metering element, with which the fluid is discharged directly into the working space, in particular sprayed. Such metering elements may be, for example, holes in a line bar, which can be opened and closed via a corresponding valve or to which metered fluid can be supplied. Preferably, however, the dosing elements are outlet nozzles, since a particularly homogeneous distribution of the fluid in the working space can be achieved via outlet nozzles. A metering element is thus a subunit of the fluid delivery device and refers solely to that component which is responsible for the introduction of the fluid into the working space in the last step of the fluid delivery. In other words, the metering element is the element through which the fluid leaves the spraying device into the working space. The fluid delivery device may further comprise at least one regulation element, for example a valve, which is actuated by the control unit to activate, deactivate and regulate the flow rate.

The specific arrangement of the metering elements may vary. The individual metering elements of a fluid delivery device are preferably arranged distributed uniformly parallel to the longitudinal axis of the work roll in the axial direction one behind the other over the entire width of the working space. This ensures that the fluid entry into the working space over the entire width of the working space is as even as possible. Often, the at least first and the at least second fluid delivery device comprises a plurality of metering elements, in particular outlet nozzles, for example three to twenty, in particular eight to fifteen and in particular ten. The specific relative arrangement of the at least first fluid delivery device to the at least second fluid delivery device may also vary. It is thus possible, for example, for one metering element of the at least first fluid delivery device to be arranged in the direction of rotation of the work roll or in the working direction of the construction machine in front of or behind a metering element, in particular outlet nozzle, of the at least second fluid delivery device. In particular for this arrangement alternative, it is preferred that the number of metering elements of the at least first fluid delivery device and the at least second fluid delivery device is the same, both fluid delivery devices thus each comprise, for example, ten metering elements, in particular outlet nozzles. Alternatively, it is possible for the metering elements of the at least first and the at least second fluid delivery device to be arranged distributed as evenly as possible in the axial direction of the work roll over the entire width of the working space, in particular on a common part of the line system, for example a line bar. Especially for this embodiment, unequal numbers of metering elements of the at least first and the at least second fluid delivery device have proven to be advantageous in order to ensure the homogeneity of the fluid entry. Thus, the number of metering elements of one fluid delivery device preferably exceeds that of the other by a metering element, so that in each case a metering element of a fluid delivery device is present in each case for the two outer sides in the axial direction of the longitudinal axis. Further preferred is a symmetrical arrangement of the metering elements. In order to increase the versatility of use of the spraying device, the individual metering elements are further preferably formed exchangeable. Specifically, for example, screwed nozzles are used, which can be replaced if necessary by nozzles of a different size. The design of the line system to the at least first or at least second fluid dispenser may also vary. Thus, it is possible, for example, for the individual metering elements of the at least first and for the individual metering elements of the at least second fluid delivery device a separate line section, for example a separate line bar, to be provided in the line system. However, it is preferred if the metering elements of the at least first and the at least second fluid delivery device are connected to the line system via a common element, for example a line bar; Both fluid dispensers thus deliver the same fluid into the working space and have an adjoining and in particular partially overlapping operating range with regard to the flow volume or discharge volume of the fluid into the working space per unit time.

The extent to which the first fluid delivery device and the second fluid delivery device differ with regard to the quantity of fluid delivered at a defined operating pressure essentially depends on the range of use of the construction machine equipped with such a spraying device. In practice, it has been found that the metering elements of the at least first and at least second fluid delivery devices are preferably designed such that at the specified operating pressure the flow rate of the fluid through a metering element of the first fluid delivery device relative to the flow rate of the fluid through a metering element the second fluid delivery device in the range of 1.8: 1 to 5: 1, in particular in the range from 2: 1 to 3: 1. In a preferred embodiment, the outlet nozzles of the first fluid delivery device are thus dimensioned so that they deliver about 25 l / min at 1 bar operating pressure and the outlet nozzles of the second fluid delivery device dimensioned so that they at the operating pressure of 1 bar about 10 l / min spray into the work space. If the metering elements of the fluid delivery devices are selected in this ratio, it is ensured that the construction machine can be used in particular over the entire range of typical recycler and stabilizer applications.

The control unit is designed, for example, such that it controls the respective metering elements, in particular the at least two metering elements, of the first and the second fluid delivery device, together. If the first fluid delivery device is activated, fluid is thus conveyed through all metering elements of the first fluid delivery device into the working space. The same applies to the metering elements of the second fluid delivery device. However, a particularly high variety of applications is made possible when the control unit is designed in such a way that it groups and in particular individually controls the at least two metering elements of the at least first fluid delivery device and / or the at least second fluid delivery device. In an individual control, it is thus possible to activate individual dosing of the first and second fluid delivery device separately. Of course, this also includes the possibility of activating several or all metering elements of a fluid delivery device at the same time or to use them for delivering fluid into the working space. Based on the entire working space is obtained with this embodiment, the possibility to introduce only in partial areas of the working space fluid in the soil material to be processed. This can be desired, for example, in the working mode, if only one in the direction of travel of the construction machine extending portion of the machining width of the construction machine to be offset with fluid. For this type of injection device, however, it is necessary for each dosing element to have a corresponding device, for example a valve, which can be controlled and regulated by the control unit. The at least first and / or at least second fluid delivery device are therefore relatively expensive to manufacture. A meaningful and thus also advantageous compromise represents a spraying device according to another preferred embodiment of the invention, in which the control unit is designed in such a way that it controls the metering of the at least first fluid dispensing device and / or the at least second fluid dispensing device grouped. For example, at least two dosing each form a Dosierelementgruppe. Metering elements of the at least first and / or the at least second fluid delivery device in this embodiment are at least partially in groups within the scope of the fluid delivery device arranged, so that for example with a valve a Dosierelementgruppe, in particular two metering elements can be activated. Of course, the number of individual dosing elements of each group can be varied and adapted to the respective needs.

In principle, the control unit can be designed in such a way that it controls the at least first and the at least second fluid delivery device in such a way that a defined volume of fluid per unit time is discharged into the working space or the flow rate of fluid is kept constant in the working space. Depending on the nature of the ground (in particular the soil density), the environmental situation on the construction site, the work settings such as depth of cut, driving speed, etc., the desired fluid volume per time or the flow rate of fluid per time into the working space can vary widely. In addition, different fluids may, for example, have different viscosities, which requires consideration of different operating pressures to obtain a desired fluid flow into the working space. In addition, other parameters may occur which have a direct or indirect influence on the delivery rate of the fluid or the fluid flow rate of the soil material to be processed. In order to nevertheless guarantee constant work results, the invention proposes, in a further aspect, to design the control unit in such a way that it switches over from the at least first fluid dispensing device to the at least second fluid dispensing device as a function of exceeding or falling below a threshold value, and vice versa. The essential basic idea of this embodiment is initially that the control unit automatically controls the discharge capacity of fluid into the working space on the basis of at least one relevant measuring parameter and regulates the amount of fluid introduced into the working space per unit of time as a function of this measuring parameter. For this purpose, at least one threshold value is stored in the control unit, the exceeding of which triggers a switchover from the at least second fluid delivery device to the more powerful at least first fluid delivery device. Such a threshold may be, for example, the flow rate, the line pressure, etc. Of course, a plurality of threshold values may be present, the exceeding of which triggers each switching. This can be ensured that the amount of fluid introduced into the working space can be relatively varied and the operating pressure is maintained at the same time in a relatively narrow range. On the other hand, if the threshold value is undershot, the control unit reacts in the opposite direction and switches over from the at least one first fluid delivery device to the at least second fluid delivery device. The at least first fluid delivery device is correspondingly deactivated and the at least second fluid delivery device is activated by the control unit. This succeeds, despite a possibly drastic reduction in the work space To keep the operating pressure in a significant range per unit time and to prevent excessive sagging of the operating pressure. As a result, on the one hand, a uniform distribution of the fluid over the entire fluid delivery device is ensured and at the same time, for example, clogging of the metering elements, in particular outlet nozzles, can be counteracted with soil material of the respective fluid delivery device, since even at low volume flow the fluid exits the metering elements with a certain minimum pressure ,

Of course, the control unit may also be designed in such a way that it automatically switches on at least one of the at least two fluid delivery devices of the at least one other fluid delivery device as a function of exceeding or falling below a maximum value. This is typically done, for example, when the more powerful at least first fluid delivery device has reached its maximum injection level from the volume of fluid per unit time or from the flow rate. The delivery rate of the injection device can then be further increased according to this further preferred embodiment by activating the less powerful at least second fluid delivery device in addition to the more powerful fluid delivery device or, as it were, adding it. In the case of this embodiment, this happens automatically when the maximum value of a suitable control parameter stored in the control unit and / or the maximum flow rate are exceeded. This may be, for example, the line pressure in the line system of the injection device, the flow rate or the discharge volume per unit of time in the working space or the like. It goes without saying that for monitoring the maximum value and also the aforementioned threshold at least one corresponding suitable sensor device must be integrated into the injection device as part of the control device, such as a pressure sensor which determines the fluid pressure in the line system and transmits it to the control unit , If the maximum value is undershot, the power-weaker at least second fluid delivery device is first deactivated by the control unit. If the corresponding parameter continues to fall and then falls below the threshold value, the control unit switches from the more powerful at least first fluid delivery device to the less powerful at least second fluid delivery device.

In principle, a multiplicity of operating parameters are suitable for defining and determining the threshold value and / or the maximum value. Particularly preferred in this connection are the monitoring and the basis of the line pressure, the flow rate of fluid per unit time, the depth of cut, the soil moisture, the soil density and / or the ground speed. Of course, it is also possible to use combinations of parameters for monitoring and controlling the spraying device. For example, the line pressure can be taken into account in addition to the driving speed and / or in addition to the flow rate fluid per unit time by a correspondingly formed control unit.

The most widely used fluid is water. However, there are also known applications in which to switch between different fluids. These fluids often have great differences in their specific properties, for example their viscosity. In these cases, it is advantageous if the control unit is designed in such a way that the threshold value and / or the maximum value vary depending on the respective fluid or are respectively adapted to the specific properties of the fluid. For each fluid, individual threshold values and / or maximum values are thus stored in the control unit in this embodiment.

By using at least two graduated fluid delivery devices with respect to their flow rate at a fixed operating pressure or comparative pressure, it is possible to substantially reduce the clogging of metering elements, in particular outlet nozzles, during operation with settling soil material. In the event that particularly critical soil materials are to be processed in this regard, it is further preferred that a cleaning device or cleaning function, in particular Düsenreinigungseinricnturng, for cleaning the at least first and the at least second fluid dispensing device is present. This can be formed, for example, in such a way that the control unit for performing the cleaning function at regular intervals a cleaning pulse by the respective existing fluid dispensing devices triggers.

A further development further provides for the integration of a fluid filter into the line system, in particular in the conveying direction of the fluid before and / or behind a fluid pump. In this way, it can be ensured particularly well that the fluid delivered to the at least first and the at least second second fluid delivery device is free of contaminants. Overall, so deposits and blockages in the pipe system can be better avoided. Of course, it is also possible to integrate a plurality of pumps in the line system, for example, to promote fluid to the at least first and the at least second fluid delivery device with separate pumps and / or provide a separate line system for each fluid.

The solution of the problem also succeeds with a construction machine for tillage, in particular a recycler to restore repaired street fixtures, a stabilizer for stabilizing non-load-bearing floors and a milling machine, especially cold planer, for milling roadway and floor coverings in the manner described above trained spraying device. These various types of construction machinery are consistent in the essential design of their work tool and the arrangement of this work tool in the construction machine. Each comprise a horizontal and transversely to the longitudinal axis or working direction of the construction machine arranged work roll, which is designed to rotate about its horizontal axis for substrate processing, for example for milling of road surfaces, for stabilizing soil or for recycling defective road pavement. The working space in which the work roll is arranged to rotate is designed to be substantially closed to the sides and upwards, for example with a cover hood, so that the work space is only opened toward the floor and, for example, for mixing the soil to be worked with Additives and / or fluids, etc., can be used. The working device or work roll is arranged directly or indirectly on the machine frame of the construction machine. The construction machine is also preferably self-propelled and has at least one front wheel and at least two rear wheels, which may have a suitable drive, for example via corresponding hydraulic motors. Alternatively, embodiments with corresponding drive crawlers are possible. For fluid supply, the construction machine may further comprise either at least one fluid reservoir for carrying the fluid or, alternatively, be connected via the conduit system with a tanker vehicle or the like for fluid supply of the spraying device. The invention provides to integrate the spraying device described above in a construction machine for soil cultivation, in particular a construction machine with the above features.

Finally, the object is also achieved by a method for operating a spraying device, in particular the spraying device of the above-described construction machine. In the method according to the invention, the flow rate of the injection device is controlled by controlling at least one first fluid delivery device and at least one second fluid delivery device by a control unit, wherein the first fluid delivery device is designed to deliver a larger fluid quantity than the second one at a predetermined operating pressure Fluid dispenser is formed. The method according to the invention is therefore characterized in that for the delivery of the same fluid into the working space at least two with respect to their respective performance at a specified reference operating pressure staggered mutually formed fluid dispensing devices are controlled by the control unit and regulated with respect to their output into the working space amount of fluid. Thus, for example, the operating pressure in the line system of the spraying device can be kept within a comparatively narrow range and at the same time the amount of fluid dispensed into the working space per unit of time can be varied widely.

A refinement of the method according to the invention provides for the regulation of the flow rate of the injection device or of the delivery of the fluid volume per unit of time into the working space as a function of overshooting and / or falling below at least one defined threshold value of at least one specific operating parameter. Thus, for example, the control unit automatically switches over from the activated at least second at least second fluid delivery device to the more powerful at least first fluid delivery device if, for example, the flow rate of the fluid per unit time and / or the operating pressure in the line system exceeds the threshold value. A similar control process may, for example, take place when the travel speed of the construction machine or the line pressure as a result of an acceleration of the engine exceeds a threshold value in order to keep the fluid input per unit volume of soil material constant. Of course, it is also possible to integrate combinations of different operating parameters for establishing a threshold value and for determining the current operating state of the construction machine in the control unit. Thus, it is possible, for example, to set the threshold taking into account the operating pressure, the depth of cut and / or simultaneously the travel speed of the construction machine and the switching between the at least first fluid delivery device and the at least second fluid delivery device depending on both the operating pressure in the line system and / or the milling depth and or to control the driving speed of the construction machine.

The switching between the fewest first and the least second fluid delivery device can basically take place without transition. This means that the at least first fluid delivery device is deactivated in the moment in which the second fluid delivery device is activated and vice versa. However, in this switching method, comparatively large pressure fluctuations in the line system can occur. In order to avoid the pressure peaks occurring during switching, the invention therefore proposes overlapping the switching between the at least first and the at least second fluid delivery device. For example, from the at least first fluid delivery device to the at least second fluid delivery device, for example when reducing the travel speed of the construction machine, from the control unit When the at least one first fluid dispensing device is activated, at least one parallel activation of the at least second fluid dispensing device takes place. After a predetermined time interval, finally, the at least first fluid dispensing device is deactivated and the entry of the fluid into the working space is continued solely by the at least second fluid dispensing device. This process is correspondingly reversed when the amount of fluid dispensed into the working space per unit time is to be increased. It is therefore essential for this embodiment of the method according to the invention that, when switching over for a transitional time interval, the at least first and the at least second fluid delivery devices are activated overlapping each other simultaneously and with respect to their activation state and release the fluid together into the working space within this time interval. After this time interval has elapsed, the desired deactivation of the respectively no longer required fluid delivery device takes place. In this way, the emergence of pressure peaks during switching is effectively prevented and significantly reduces the pressure load on the piping system.

Fig. 1

Seitenansicht einer gattungsgemäßen Baumaschine;

Fig. 2

Seitenschnittansicht in den Arbeitsraum der Baumaschine aus Fig. 1;

Fig. 3

Aufbau einer Einsprüheinrichtung gemäß einer ersten Ausführungsform;

Fig. 4

Aufbau einer Einsprüheinrichtung gemäß einer zweiten Ausführungsform;

Fig. 5

Aufbau einer Einsprüheinrichtung gemäß einer dritten Ausführungsform; und

Fig. 6

Ablaufdiagramm eines Verfahrens zur Steuerung der Einsprüheinrichtung aus Fig. 5.

The invention will be explained in more detail with reference to several embodiments. They show schematically:

Fig. 1

Side view of a generic construction machine;

Fig. 2

Side sectional view into the working space of the construction machine Fig. 1 ;

Fig. 3

Structure of a spraying device according to a first embodiment;

Fig. 4

Structure of a spraying device according to a second embodiment;

Fig. 5

Structure of a spraying device according to a third embodiment; and

Fig. 6

Flowchart of a method for controlling the sprayer from Fig. 5 ,

Identical components are indicated in the figures with the same reference numerals.

Fig. 1 relates to a construction machine 1, specifically in Fig. 1 a so-called stabilizer or, depending on the application, a recycler. The construction machine 1 initially comprises a machine frame 2, a pair of front wheels 3 and a pair of rear wheels 4, wherein only the respective wheel located in the working direction a on the left side is visible. The machine frame 2 further has a two-part construction, comprising two frame members, which are connected to each other with an articulated joint 5. At the height of the articulated joint 5, a height-adjustable arrow direction b along the driver's cab 6 is further arranged. The drive energy required is obtained by means of a drive device 7, which both the driving energy required for driving the construction machine 1 as well as for driving the work device to be explained in more detail below Provides. The construction machine 1 is used for processing of floors or roadways and has to the working device in the form of a work roll on (in Fig. 1 not visible). The work roll is mounted rotatably about its cylinder axis indirectly on the machine frame 2 of the construction machine 1 and surrounded by a protective hood 8, which closes the space around the working device upwards and to the sides. Downwards or towards the bottom 9, the protective cover 8 is open. The protective cover 8 thus encloses a working space in which the work roll is mounted. The work roll is relative to the protective cover 8 and the machine frame 2 in the direction of arrow c adjustable in height and has for this purpose a corresponding adjustment or pivoting device. In the in Fig. 1 This position of the work roll is assumed, for example, in the transport mode of the construction machine, whereas the work roll is lowered in working mode or tillage mode down and immersed in the ground with the desired depth , For tillage the construction machine 1 is moved in the direction of arrow a (forward direction) on the ground 9.

The concrete structure of the protective hood 8 bell-like covered working space 10 is in the sectional view through the guard 8 from Fig. 1 perpendicular to the axis of rotation of the work roll and in the direction of a in Fig. 2 shown in more detail. The protective cover 8 accordingly encloses the working space 10 upwards and towards the sides. On the other hand, downwards or in the direction of the roadway bottom 9, the hood 8 is designed to be open, so that the work roll 11 surrounded by the hood 8 is in contact with the ground 9 to be processed by lowering the work roll 11 in the direction of the arrow c (FIG. Fig. 1 ) can be brought. The work roll 11 is disposed inside the protective hood 8. The longitudinal axis 12 of the work roll 11 extends horizontally and perpendicular to the finished movement direction a of the construction machine 1. On the outside of the cylindrical work roll 11 is a plurality of teeth 13, specifically arranged on a unspecified bit holder or, depending on the embodiment, chisel change holder system. The work roll 11 rotates about its cylinder axis 12 in the direction of arrow d, ie counter to the direction of movement of the construction machine 1. The work roll 11 thus carries soil material in the depth .DELTA.T, comprising the roadway bottom 9 and a portion of the underlying lower layer 14 and places them in the direction of travel a behind the work roll again. The lying between the work roll and the protective cover 8 interior can be used as a mixing room.

For introducing fluid, in particular water, into the working space 10 which is delimited outwardly from the protective hood 8, an outlet nozzle 15 ("large" outlet nozzle) protrudes from the outside. and an outlet nozzle 16 ("small" outlet nozzle) located in front of it in the axial direction of the cylinder axis 12 with its respective fluid outlet opening into the interior of the working space 10. Both outlet nozzles 15 and 16 each have a respective regulating element, in each case a valve (not indicated; Responding to valves, wherein other suitable control elements can be used instead), to a line bar 17, which is part of a line system connected. There are also more identical outlet nozzles 15 and 16 are provided, which are arranged along the axis of rotation alternately in the viewing direction behind the two outlet nozzles 15 and 16 on the line bar 17, available. In principle, it is also possible that instead of the outlet nozzles simple holes are used in the line beam, but exit nozzles are preferred.

The piping system further comprises a water reservoir, which is mounted on the construction machine 1 (in Fig. 2 not visible), as well as a pump (in Fig. 2 also not visible), which promotes the water from the reservoir via the line system to the outlet nozzles 15 and 16 out. The pump is further configured to pressurize the conduit system 17. If the respective valve of the large outlet nozzle 15 and / or the small outlet nozzle 16 is opened, the fluid coming from the conduit bar 17 passes through the outlet nozzle 15 and / or the outlet nozzle 16 and thereby passes into the working space 10.

The outlet nozzle 15 is part of a first fluid dispensing device and the outlet nozzle 16 is part of a second fluid dispensing device. The basic structure of the concrete spraying device Fig. 2 is in different embodiments in the FIGS. 4 and 5 illustrated in more detail. In the embodiment of Fig. 3 two line bars 17.1 and 17.2 are arranged one behind the other in the direction of rotation. Further details of the sprayer in various embodiments are further illustrated below.

Fig. 3 relates to a spraying device 18a according to a first embodiment. The fluid, in the present case water, is at the sprayer 18a from a discharge point 19, which is for example a tank connection or a connection to a tanker, via a line system 20 to a first fluid dispenser 21, comprising the large outlet nozzles 15.1 to 15.6 and the valve 22, and to a second fluid dispenser 23, comprising the small outlet nozzles 16.1 to 16.6 and the valve 24, passed. The line system 20 has a water pump 25, a pressure sensor 26, a flow meter 27 and a Stopcock 28 on. Optionally, a filter 29 (in FIGS. 4 and 5 ) between the water pump 25 and the stopcock 28 in the wiring harness of the conduit system 20 may be integrated.

The line system 20 further comprises a first line bar 17.1 and a second line bar 17.2. The first line bar 17. 1 is fluidically connected to the remaining part of the line system 20 via the valve 22 of the first fluid delivery device 21. On the line bar 17.1, the six large outlet nozzles 15.1 to 15.6 are also arranged in parallel. If the valve 22 is opened, fluid flows through the valve 22 upstream of the part of the line system (driven by the pump 25) through the valve 22 in the line bar 17.1 and is distributed from there to the individual outlet nozzles 15.1 to 15.6 and passes through the outlet nozzles 15.1 to 15.6 in the working space 10 off. The outlet nozzles 15.1 to 15.6 are thus the metering elements of the first fluid delivery device 21. The second fluid delivery device 23 has a comparable structure. There, the small outlet nozzles 16.1 to 16.6 are connected to the second line bar 17.2, which communicates with the remaining part of the line system 20 via the valve 24 of the second fluid dispensing device 23. If the valve 24 is open and the pump 25 is in operation, fluid is pumped through the conduit system 20 through the valve 24 into the conduit bar 17.2 and leaves it in the working space 10 through the individual metering of the second fluid delivery device 23 and through the outlet nozzles 16.1 to 16.6, which are also connected in parallel. The large outlet nozzles 15.1 to 15.6 are outlet nozzles which at 1 bar operating pressure (measured with the pressure sensor 26 in the line system 20) per nozzle 25 l / min fluid and at 5 bar operating pressure 60 l / min fluid in the working space per nozzle submit. The small nozzles 16.1 to 16.6, however, are designed in such a way that they deliver 10 l / min of fluid per nozzle and at operating pressure of 5 bar 25 l / min in the working space at an operating pressure of 1 bar. The large and the small outlet nozzles 15.1 to 16.6 are thus selected in relation to each other so that their respective outlet volumes at a certain operating pressure of 1 to 5 bar complement each other almost without overlap.

Another essential element of the spraying device 18 is a control unit 30a. This is, as indicated by the dashed and dotted lines, connected to the pump 25, the pressure sensor 26, the flow meter 27, the stopcock 28, the valve 22 of the first fluid dispenser 21 and the valve 24 of the second fluid dispenser 23. The control unit 30 is configured to regulate and control the flow rate of the fluid through the spray means 18 and the first fluid discharge device 21 and the second fluid discharge device 23 into the work space 10, respectively. The control unit 30 is also in the way designed to include an input field, via which an operator can enter desired values, fluid properties, ground properties, etc., or parameters that are generally relevant for the machining process. The basic idea of the invention is to design the spraying device 18 such that it comprises at least two fluid delivery devices (in the present case the first fluid delivery device 21 and the second fluid delivery device 23) with different capacities per unit time with respect to the flow rate of fluid at a fixed operating pressure or time unit. Comparative pressure and these coordinated with each other to control. If it is desired to introduce large amounts of fluid into the working space 10, the control unit 30 opens the valve 22 of the first fluid delivery device 21, so that 25 l / min of fluid exits into the working space 10 per nozzle at an operating pressure of, for example, 1 bar in the line system 20 , If, on the other hand, a smaller amount of fluid is desired, the control unit 30 closes the valve 22 of the first fluid delivery device 21, whereby the fluid entry into the working space 10 is shut off by the large outlet nozzles 15.1 to 15.6. By contrast, the control unit 30 opens the valve 24 of the second fluid delivery device 23, so that the fluid exits through the small outlet nozzles 16.1 to 16.3 into the working space 10. If the operating pressure is 1 bar, 10 l / min per nozzle are entered into the working area in this case. When the operating pressure is increased, for example, because the depth of cut is increased and / or the working speed of the construction machine is increased, finally, upon reaching the threshold of 5 bar, the control unit switches from the second fluid dispenser 23 with small nozzles to the first fluid dispenser 21 with large nozzles lowers the operating pressure accordingly, in the present case specifically initially to 1 bar.

Overall, the control unit 30a, the control process for controlling the sprayer 18 thus taking into account measurement parameters, in the specific example, for example, the milling depth and / or the travel speed of the construction machine adapt. For example, the control unit 30 can detect the cutting depth and / or travel speed of the construction machine or the processing speed via suitable sensors and the fluid discharge or the flow rate fluid per unit time by regulating the pump 25 and / or the valves 22 and 24 of the first fluid delivery device 21 or the second fluid delivery device 23 adapt to the travel speed of the construction machine. Other measurement parameters may be, for example, the operating pressure of the fluid in the line system 20, the applied power of the pump 25, etc.

Obviously, in order to obtain the maximum flow rate per unit time of the injection device 18, it is also possible for the control unit to control both the first fluid delivery device 21 as well as the second fluid dispensing device 23 is activated so that fluid can simultaneously escape through the outlet nozzles 15.1 to 15.6 and 16.1 to 16.6 into the working space 10.

Basically, it is with the help of the control unit 30a and the Einsprüheinrichtung 18a Fig. 3 Thus, at comparatively low pressure fluctuations in the operating pressure (in the present example, between 1 bar and 5 bar), the flow rate of the fluid over a wide range (present between 10 l / min at a 1 bar operating pressure and activated second fluid dispenser 23 and deactivated first fluid dispenser 21 to to 85 l / min at 5 bar and activated first fluid dispenser 21 and simultaneously activated second fluid dispenser 23) to cover a wide range of desired delivery volumes. Since, in this way, further extreme pressure ranges in the line system can be excluded, at least during normal operation, it is ensured, for example, that a uniform amount of fluid exits from each outlet nozzle 15.1 to 15.6 or, depending on the activation state, 16.1 to 16.6 into the working space 10. At the same time, a certain minimum pressure at the outlet nozzles 15.1 to 15.6 to 16.1 to 16.6 can be ensured during operation over a wide range, whereby clogging of the corresponding outlet nozzles by soil material can be effectively counteracted.

Another embodiment of a spraying device 18b is shown in FIG Fig. 4 illustrated. With regard to the basic construction of the conduit system 20 and the metering elements designed as outlet nozzles 15.1 to 15.6 and 16.1 to 16.6, reference is made to the statements on the preceding exemplary embodiment. The second fluid delivery device comprises an additional metering element 16.7, thus has the number of metering elements of the first fluid delivery device +1.

The essential difference between the spray-in device 18b and the spray-in device 18a lies in the control of the large outlet nozzles 15.1 to 15.6 and the small outlet nozzles 16.1 to 16.7. In contrast to the previous embodiment, the control of the individual outlet nozzles takes place here individually and separately, ie individually, from the control unit 30b. Each of the metering elements or outlet nozzles 15.1 to 15.6 and 16.1 to 16.7 has for this purpose in each case a suitable valve which can be controlled and regulated by the control unit 30b, for example opened and closed. The individual valves are for clarity in Fig. 4 not specified and there graphically each part of the corresponding outlet nozzle 15.1 to 15.6 and 16.1 to 16.7. The first fluid delivery device 21 accordingly comprises the entirety of the individual large metering elements or the outlet nozzles 15.1 to 15.6 including their separately controlled by the control unit valves. By contrast, the second fluid delivery device 23 designates the entirety of the small metering elements or the outlet nozzles 16.1 to 16.7, including the in Fig. 4 also not specified and controlled by the control unit 30b valves.

A further special feature of the spraying device 18b is that both the metering elements of the first fluid delivery device 21 (outlet nozzles 15.1 to 15.6) and the metering elements of the second fluid delivery device 23 (metering elements 16.1 to 16.7) are arranged together on the conduit bar 17. Thus, the space requirement in the direction of rotation of the work roll in the working space 10 in the protective hood of the sprayer 18b, for example, much lower than the space requirement of the sprayer 18a with the two in the direction of rotation d of the work roll one behind the other line beams 17.1 and 17.2.

It is also essential in the case of the spraying device 18b that individual metering elements of the first fluid delivery device 21 are distributed over the entire width of the protective cover alternately to the metering elements of the second fluid delivery device 23 and are arranged lying in a line in the axial direction of the rotation axis 12. The large outlet nozzles 15.1 to 15.6 thus alternate with the small outlet nozzles 16.1 to 16.7 in the axial direction 12 or transversely to the working direction of the construction machine at regular intervals from each other. Thus, if all the large outlet nozzles 15.1 to 15.6 or all small outlet nozzles 16.1 to 16.6 or even all the outlet nozzles 15.1 to 15.6 and 16.1 to 16.6 are activated or flowed through by the fluid, the fluid is distributed uniformly over the entire width of the working space 10. On the other hand, the individual control of individual outlet nozzles enables the selective activation of a subgroup of the outlet nozzles 15.1 to 15.6 of the first fluid dispenser 21 and / or the outlet nozzles 16.1 to 16.6 of the second fluid dispenser 23. It is thus possible that only over a part of the total working width of the work roll 11 Fluid is introduced into the working space 10. Based on the entire working width thus only a partial strip is added during operation with fluid. Overall, the sprayer 18B therefore allows a highly selective and individualized displacement of the soil to be processed with the fluid. It is also important that to the two outer sides of the line beam 17 and in the axial direction of the working space (that direction in which the longitudinal axis 12 of the work roll extends in the working space) similar dosing 16.6 and 16.7 are arranged. This feature also contributes to the homogeneous distribution of the fluid in the working space.

Another difference lies in the arrangement of a filter 29 in the line system 20. The filter 29 is arranged in the flow direction of the fluid behind the pump 25 or between the pump 25 and the line bar 17 and the branch of the line system in front of the line bar 17.

Another embodiment of a spraying device 18c is shown in FIG Fig. 5 which represents a particularly well-proven in practice compromise between the sprayer 18a and 18b.

The basic arrangement of the individual components of the spraying device 18c corresponds to the spraying device 18b (wherein the external metering element 16.7 is missing in the spraying device of FIG. 18c). The essential difference lies in the fact that the metering elements 15.1 to 16.6 are grouped, specifically grouped in pairs, interconnected and controlled by the control unit 30c. For example, the two outlet nozzles 15.1 and 15.2 form the metering element group G1, the outlet nozzles 15.3 and 15.4 the metering element group G2 and the outlet nozzles 15.5 and 15.6 the metering element group G3. The metering element groups G1 to G3 (including the valves (also not shown upstream of each discharge nozzle 15.1 to 15.6) form the first fluid delivery device 21 overall. The metering elements of the second fluid delivery device 23 are also arranged in pairs. The outlet nozzles 16.1 and 16.2 form the metering element group K1, the outlet nozzles 16.3 and 16.4 the metering element group K2 and the outlet nozzles 16.5 and 16.6 the metering element group K3. The control unit 30c can now individually control and regulate the operating state of each individual group G1, G2, G3, K1, K2 and K3 (in FIG Fig. 5 indicated by the indicated in different thickness dotted and dashed switching connections between the control unit 30c and the individual metering elements 15.1 to 16.6). Thus, it is also possible with the injection device 18 c to control individual segments of the first fluid delivery device 21 and / or the second fluid delivery device 23 individually and independently of one another with respect to operating state and flow rate. At the same time, the interconnection of the control unit 30c with the respective fluid dispensers 21 and 23 can be simplified, since not every metering element must be in contact with the control unit 30c via a single and individual signal connection, but only the metering element groups G1 to G3 and K1 to K3 respectively.

Fig. 6 illustrates the operation of the control method of the groups G1 to G3 and K1 to K3 of the sprayer 18c Fig. 5 , In its fundamental principles, this control method can also be applied to the two spray-in devices 18a and 18b to a reasonable extent. Fig. 6a ) relates to the increase in the working space 10 of the sprayer 18 fluid volume per time (V / t) (V1 <V2). The timeline is directed downwards and marked with t. To the right of the V / t diagram, the metering element groups G1 to G3 of the first fluid delivery device 21 and K1 to K3 of the second fluid delivery device 23 are indicated. If a bar is present, the respective metering element group G1 to G3 and K1 to K3 is activated or is traversed by fluid or releases fluid into the working space. If there is no bar under the corresponding metering element group at a certain point in time, the respective metering element group is deactivated or closed or does not deliver any fluid into the working space. The control of the activation states takes place via the control unit 30c.

Fig. 6a illustrates in the left diagram that at time t1, the flow rate of the per unit time to be dispensed into the working space fluid volume from the volume V ₁ to the volume V ₂ by control measures of the control unit 30 c is increased. From time t ₁ to time t ₂ , the corresponding volume flow is increased from V ₁ to V ₂ . At the time t ₃ , which is between the time t ₁ and t ₂ , a predetermined threshold value S _{w is} exceeded. The control unit 30c registers this exceeding and changes from the small outlet nozzles or the dosing element groups K1 to K3 toward the large outlet nozzles or the dosing element groups G1 to G3. When the threshold value S _w is exceeded, the control unit thus switches over between the second fluid delivery device 23 and the first fluid delivery device 21. It is essential in this step that this switching does not take place ad hoc at the time t ₃ , but extends over a period t _u , which begins with the exceeding of the threshold value S _w . Over the period Δt _u , both the originally activated and not yet switched-off second fluid delivery device 23 and the first fluid delivery device 21 newly activated by the control unit are activated jointly or overlapping. Only after the expiration of the time window .DELTA.t _u , the control unit switches off the second fluid delivery device 23. If the amount of fluid to be metered, however, lowered in the working mode, takes place in Fig. 6a specified procedure in reverse order. Characterized in that there is an overlap region when switching between the two fluid dispensers 21 and 23, the emergence of pressure spikes in the conduit system 20 when switching the fluid dispensers 21 and 23 can be avoided or at least substantially reduced.

The spraying device 18c Fig. 5 also allows the individual control of each two as a group G1, G2, G3, K1, K2 or K3 circuitry summarized Dosierelementpaare or outlet nozzle pairs. This should be in Fig. 6a are illustrated by the black colored webs of groups G1 and K1. In addition to the common activation with the respective additional two gray-colored groups, the sole activation and switching between the groups K1 and G1 is thus possible, for example.

Fig. 6b Finally, the control of the spraying device 18c is illustrated by the control unit 30c Fig. 5 taking into account the driving speed v of a suitably equipped construction machine. The driving speed is here only an example to illustrate the basic operation. Alternatively or additionally, the depth of cut, changing soil properties, the flow rate, etc., can be used for the regulation in order to ensure a continuous distribution of fluid in the soil material to be processed. In the left graph according to Fig. 6b Thus, the speed v or the speed of the construction machine is reproduced.

At time t ₁ , the machine accelerates, exceeding the threshold value S _w . The control unit 30c triggers, comparable to the process Fig. 6a , the switching from the Dosierelementgruppe the second fluid dispenser 23 K1 to K3 on the Dosierelementgruppen G1 to G3 of the first fluid dispenser 21 to allow even at increased operating speed the desired fluid entry into the soil material to be processed. For clarity, is in Fig. 6b ]) the course of the volume flow is not specified. However, this ultimately runs parallel to the development of the driving speed. As the driving speed increases, the amount of fluid discharged from the spraying device 18c into the working space increases and vice versa. This ensures that a constant amount of fluid is introduced into the soil material to be processed per section even at different speeds.

Finally, at time t ₄ , the construction machine accelerates until time t ₅ , exceeding maximum value M _w at time t ₆ . The maximum value is based on the maximum output quantity of the fluid in the working space by means of the more efficient fluid dispensing device 21. In order nevertheless to ensure adequate supply of the working space with fluid even at maximum travel speed during operation, the control unit switches on exceeding the maximum value M _{w in} addition to the first Fluid dispenser 21 the Dosierelementgruppen K1 to K3 of the second fluid dispenser 23 added so that afterwards both fluid dispensers 21 and 23 are operated in parallel. Will the working speed of the Construction machine then lowered at the time t ₇ to the time t ₈ , the vehicle speed drops below the maximum value M _w at the time t ₉ and below the threshold value S _w at the time t ₁₀ . When the value falls below the maximum value M _w , the control unit first inactivates the fluid delivery of the metering element groups K1 to K3 of the second fluid delivery device 23. When the threshold value is undershot, the control unit switches from the metering element groups G1 to G3 of the first fluid delivery device 21 to the metering element groups K1 to K3 of the second fluid delivery device, in which case switching takes place overlappingly over the time interval Δt _{u in order} to prevent pressure peaks in the line system.

Of course, control of the spraying device 18c adapted to the driving speed can also be carried out selectively with one or two metering element groups of the first fluid delivery device 21 and / or the second fluid delivery device 23. This is in Fig. 6b by the respective average Dosierelementgruppe G2 and K2, which are colored black, respectively.

Neither in Fig. 6a ) still in Fig. 6b On the other hand, further regulation processes are indicated, which are controlled and regulated by the control unit 30c. This concerns, for example, the regulation of the pump power, the pump speed, the control of the line pressure, etc.

Claims (16)

1. A spraying device (18a, b, c) for introducing a fluid into a working chamber (10) of a working roller (11) of a construction machine (1) for processing the ground (9) or road surfaces, comprising

   - a line system (20) via which fluid is guided to an at least first (21) and an at least second (23) fluid delivery apparatus;

   - and a control unit (30a, b, c) for controlling the fluid delivery via the at least first (21) and the at least second (23) fluid delivery device,

   characterized in that
   fluid can be delivered to the working chamber (10) via the at least first (21) and the at least second (23) fluid delivery apparatus, and that the first fluid delivery apparatus (21) is implemented to deliver a larger fluid quantity than the second fluid delivery apparatus (23) at a fixed operating pressure, so that, per unit of time, the at least first fluid delivery apparatus (21) supplies a larger fluid volume to the working chamber than the at least second fluid delivery apparatus (23), and wherein the control unit (30a, b, c) is implemented in such a manner that it controls the at least first fluid delivery apparatus (21) and the at least second fluid delivery apparatus (23) independently from one another.
2. The spraying device (18a, b, c) according to claim 1,
   characterized in that
   the at least first (21) and the at least second (23) fluid delivery device each comprise at least two dosing elements, especially outlet nozzles (15.1 to 15.6, 16.1 to 16.7).
3. The spraying device (18a, b, c) according to claim 2,
   characterized in that
   the dosing elements (15.1 to 15.6, 16.1 to 16.7) of the at least first (21) and the at least second (23) fluid delivery device are arranged in the manner that at a fixed operating pressure the flow rate of the fluid through the dosing element (15.1 to 15.6) of the first fluid delivery device (21) is in the range of 1.8:1 to 5:1, especially in the range of 2:1 to 3:1, at a ratio to the flow rate of the fluid through a dosing element (16.1 to 16.6) of the second fluid delivery device (23).
4. The spraying device (18b) according to any one of claims 2 or 3,
   characterized in that
   the control unit (30b) is arranged in the manner that it individually triggers the at least two dosing elements (15.1 to 15.6, 16.1 to 16.7) of the at least first fluid delivery device (21) and/or the at least second fluid delivery device (23).
5. The spraying device (18c) according to any one of claims 2 or 3,
   characterized in that
   the control unit (30c) is arranged in the manner that it triggers the dosing elements (15.1 to 15.6, 16.1 to 16.7) of the at least first fluid delivery device (21) and/or the at least second fluid delivery device (23) in a grouped manner.
6. The spraying device (18a, b, c) according to any one of the preceding claims,
   characterized in that
   the control unit (30a, b, c) is arranged in the manner that it switches over from the at least first fluid delivery device (21) to the at least second fluid delivery device (23) depending on exceeding or falling below a threshold value (Sw).
7. The spraying device (18a, b, c) according to any one of the preceding claims,
   characterized in that
   the control unit (30a, b, c) is arranged in such a manner that, upon exceeding or falling below a maximum value (Mw), it will activate at least one of the at least two fluid delivery devices (21, 23) in addition to the at least other fluid delivery device (21, 23), or will deactivate at least one of the at least two fluid delivery devices (21, 23).
8. The spraying device (18a, b, c) according to any one of claims 6 or 7,
   characterized in that
   the threshold value (Sw) or the maximum value (Mw) is a line pressure, a milling depth, a travelling speed and/or a flow rate.
9. The spraying device (18a, b, c) according to any one of the claims 6 to 8,
   characterized in that
   the control unit (30a, b, c) is arranged in the manner that the threshold value (Sw) or the maximum value (Mw) vary depending on the fluid.
10. The spraying device (18a, b, c) according to any one of the preceding claims,
    characterized in that
    a cleaning device, especially a nozzle cleaning device, is provided for cleaning the at least first and at least second fluid delivery apparatus (21, 23).
11. The spraying device (18a, b, c) according to any one of the preceding claims,
    characterized in that
    the line system (20) comprises a fluid filter (29), especially before or after a fluid pump (19).
12. A construction machine (1) for processing the ground, especially a recycler, stabilizer or cold milling machine, comprising a spraying device (18a, b, c) according to any one of claims 1 to 11.
13. A method for operating a spraying device (18a, b, c) of a construction machine (1) according to claim 12,
    characterized in that
    it comprises control of the flow rate of the spraying device (18a, b, c) by triggering at least one first fluid delivery device (21) and at least one second fluid delivery device (23) by a control unit (30a, b, c), with the first fluid delivery device (23) being arranged in the manner that at fixed operating pressure it is arranged to supply a larger fluid quantity than the second fluid delivery device (23), so that, per unit of time, the at least first fluid delivery apparatus (21) supplies a larger fluid volume to the working chamber than the at least second fluid delivery apparatus (23).
14. The method for operating a spraying device according to claim 13,
    characterized in that
    the control occurs depending on exceeding or falling beneath at least one fixed threshold value (Sw) of a specific operating parameter.
15. The method for operating a spraying device according to any one of claims 13 or 14, characterized in that
    the control occurs depending on the travelling speed of a construction machine, especially the construction machine (1) according to claim 12, depending on the line pressure and/or depending on the flow rate.
16. The method for operating a spraying device according to any one of claims 13 to 15,
    characterized in that
    the changeover between the at least first (21) and the at least second (23) fluid delivery device occurs in an overlapping manner.

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