Spraying device for a construction machine for processing the ground, a construction machine with a spraying device and a method for operating a spraying device

Abstract

A spraying device for introducing a fluid into the working chamber of a construction machine for processing the ground or road surfaces, comprises two fluid delivery apparatuses, a line system and a control unit. The present invention further relates to a construction machine, especially a recycler, a stabilizer or a cold milling machine, comprising such a spraying device and a method for operating such a spraying device.

Claims

1. A construction machine comprising one of a recycler, a stabilizer or a cold milling machine including a spraying device configured to introduce a fluid into a single working chamber of a working roller of the construction machine, with the working roller being configured to remove ground or road surfaces during processing by the construction machine, wherein the spraying device comprises: at least one first and at least one second fluid delivery device via which the fluid is introduced into the single working chamber of the working roller of the construction machine, with the at least one first fluid delivery device having at least one dosing element being dimensioned to deliver a larger fluid quantity than at least one dosing element of the at least one second fluid delivery device at a fixed operating pressure so that, per unit of time, the at least one dosing element of the first fluid delivery device supplies a larger fluid volume to the single working chamber than the at least one dosing element of the second fluid delivery device; a line system via which the fluid is guided to the at least one first and the at least one second fluid delivery device; and a control unit configured to control a volume of fluid delivered to the single working chamber via the at least one first and the at least one second fluid delivery device by controlling activation of the at least one first and the at least one second fluid delivery device individually from each other such that activation by the control unit comprises selectively operating each of: (i) only the at least one first fluid delivery device, (ii) only the at least one second fluid delivery device, and (iii) the at least one first and the at least one second fluid delivery device at the same time.

2. The construction machine according to claim 1, wherein each of the at least one first and the at least one second fluid delivery devices comprises at least two dosing elements.

3. The construction machine according to claim 2, wherein the at least two dosing elements of the at least one first and the at least one second fluid delivery devices are arranged in a manner that, at a fixed operating pressure, the flow rate of the fluid through one of the at least two dosing elements of the first fluid delivery device is in the range of 1.8:1 to 5:1 at a ratio to the flow rate of the fluid through one of the at least two dosing elements of the second fluid delivery device.

4. The construction machine according to claim 3, wherein at the fixed operating pressure, the flow rate of the fluid through one of the at least two dosing elements of the first fluid delivery device is in the range of 2:1 to 3:1 at a ratio to the flow rate of the fluid through one of the at least two dosing elements of the second fluid delivery device.

5. The construction machine according to claim 2, wherein the control unit is arranged in a manner that it individually triggers the at least two dosing elements of the at least one first fluid delivery device and/or the at least one second fluid delivery device.

6. The construction machine according to claim 2, wherein the control unit is arranged in a manner that it triggers the at least two dosing elements of the at least one first fluid delivery device and/or the at least one second fluid delivery device in a grouped manner.

7. The construction machine according to claim 2, wherein the at least two dosing elements comprise outlet nozzles.

8. The construction machine according to claim 1, wherein the control unit is arranged in a manner that it switches over from the at least one first fluid delivery device to the at least one second fluid delivery device depending on exceeding or falling below a threshold value (Sw).

9. The construction machine according to claim 1, wherein upon exceeding or falling below a maximum value (Mw), the control unit will activate at least one of the at least one first and the at least one second fluid delivery devices, or will deactivate at least one of the at least one first and the at least one second fluid delivery devices.

10. The construction machine according to claim 9, wherein the threshold value (Sw) and/or the maximum value (Mw) is a line pressure, a milling depth, a travelling speed and/or a flow rate.

11. The construction machine according to claim 9, wherein the control unit is arranged in the manner that the threshold value (Sw) and/or the maximum value (Mw) vary depending on the fluid.

12. The construction machine according to claim 1, wherein a cleaning device is provided for cleaning the at least one first and at least one second fluid delivery devices.

13. The construction machine according to claim 12, wherein the cleaning device comprises a nozzle cleaning device.

14. The construction machine according to claim 1, wherein the line system comprises a fluid filter.

15. The construction machine according to claim 14, wherein the fluid filter is located before or after a fluid pump.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be explained below by reference to several embodiments shown in the schematic drawings, wherein:

(2) FIG. 1 shows a side view of a generic construction machine;

(3) FIG. 2 shows a sectional side view into the working chamber of the construction machine of FIG. 1;

(4) FIG. 3 shows the arrangement of a spraying device according to a first embodiment;

(5) FIG. 4 shows the arrangement of a spraying device according to a second embodiment;

(6) FIG. 5 shows the arrangement of a spraying device according to a third embodiment; and

(7) FIG. 6 shows a flowchart of a process for controlling the spraying device of FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

(8) FIG. 1 relates to a construction machine 1, specifically in FIG. 1 a so-called stabilizer or a recycler, which depends on the respective application. The construction machine 1 comprises a machine frame 2, a pair of front wheels 3 and a pair of rear wheels 4, with merely the wheel disposed in the working direction a on the left side being visible. The machine frame 2 has a two-element configuration comprising two frame elements which are connected with each other by a knee-joint connection 5. A driver's cabin 6 is arranged at the level of the knee-joint connection 5, which cabin is height-adjustable along the direction of arrow b. The required drive power is provided by means of a drive apparatus 7 which provides the drive power required both for driving the construction machine 1 and for driving the working device which will be explained below in closer detail. The construction machine 1 is used for processing ground or road surfaces and the working device comprises a working roller for this purpose (not shown in FIG. 1). The working roller is mounted indirectly on the machine frame 2 of the construction machine 1 to be rotatable about its cylindrical axis and is enclosed by a protective hood 8 which encloses the working device upwardly and to the sides. The protective hood 8 is provided with an open configuration downwardly and towards the ground 9. The protective hood 8 thus encloses a working chamber in which the working roller is held. The working roller is height-adjustable in the direction of arrow c relative to the protective hood 8 and to the machine frame 2 and comprises a respective adjusting or pivoting apparatus for this purpose. In the position as shown in FIG. 1 the working roller is position upwardly and is not in contact with the ground 9 to be processed. This position of the working roller is assumed for example in the transport mode of the construction machine 1, whereas the working roller is lowered downwardly in the working mode or ground processing mode and presses into the ground in the depth as desired. The construction machine is moved in the direction of arrow a (forward direction) over the ground 9.

(9) The concrete configuration of the working chamber 10 which is covered in a bell-like manner by the protective hood 8 is shown in closer detail in the sectional view of the protective hood 8 of FIG. 1 perpendicularly to the rotational axis of the working roller and in FIG. 2 in the working direction a. The protective hood 8 therefore encloses the working chamber 10 upwardly and towards the sides. The hood 8 is provided with an open arrangement in a downward direction and in the direction towards the ground 9 of the road, so that the working roller 11 which is enclosed by the hood 8 can be brought into contact with the ground 9 to be processed by lowering the working roller 11 in the direction of arrow c (FIG. 1). The working roller 11 is arranged in the interior of the protective hood 8. The longitudinal axis 12 of the working roller 11 extends horizontally and perpendicularly to the direction of movement a of the construction machine 1. A plurality of teeth 13 is arranged specifically by way of tool holder system or a tool-changing holder system (depending on the embodiment) on the outside of the cylindrical working roller 11. The working roller 11 rotates about its cylinder axis 12 in the direction of arrow d, i.e., in the opposite direction to the direction of movement of the construction machine 1. The working roller 11 thus removes ground material in the depth ΔT, comprising the ground 9 of the road and a part of the underlying substructure 14 and deposits the same behind the working roller in the travelling direction a. The interior space disposed between the working roller and the protective hood 8 can be used as a mixing space.

(10) For the purpose of introducing fluid, especially water, into the working chamber 10 which is delimited by the protective hood 8, an outlet nozzle 15 (“large” outlet nozzle) and an outlet nozzle 16 (“small” outlet nozzle) which is disposed in front of the former in the axial direction of the cylinder axis 12 protrude from the outside with their respective fluid outlet opening into the interior space of the working chamber 10. Both outlet nozzles 15 and 16 are each connected via a regulation element, which is specifically a respective valve (not indicated; valves will be indicated specifically below, wherein other suitable control elements can also be used), to a line beam 17 which is part of a line system. Further structurally identical outlet nozzles 15 and 16 are present which are arranged on the line beam 17 in an alternating manner in a direction of view behind the two outlet nozzles 15 and 16. Although it is principally also possible to use simple holes in the line beam instead of the outlet nozzles, the outlet nozzles are preferable however.

(11) The line system further comprises a water reservoir which is mounted on the construction machine 1 (not shown in FIG. 2) and a pump (also not shown in FIG. 2) which conveys the water from the reservoir via the line system to the outlet nozzles 15 and 16. The pump is further arranged in the manner that it pressurizes the line system 17. When the respective valve of the large outlet nozzle 15 and/or the small outlet nozzle 16 is opened, the fluid arriving from the line beam 17 passes through the outlet nozzle 15 and/or the outlet nozzle 16 and thereby reaches the working chamber 10.

(12) The outlet nozzle 15 is part of a first fluid delivery apparatus and the outlet nozzle 16 is part of a second fluid delivery apparatus. The principal configuration of the specific spraying device of FIG. 2 is explained in closer detail in the various embodiments in FIGS. 4 and 5. Two line beams 17.1 and 17.2 are arranged behind one another in the rotational direction in the embodiment of FIG. 3. Further details of the spraying device in different embodiments will be explained below in closer detail.

(13) FIG. 3 relates to a spraying device 18a according to a first embodiment. The fluid, which is water in the present case, is conducted in the spraying device 18a from a feed point 19 which usually concerns a tanking connection or a connection to a tanker via a line system 20 to a first fluid delivery apparatus 21, comprising the large outlet nozzles 15.1 to 15.6 and the valve 22, and to a second fluid delivery apparatus 23, comprising the small outlet nozzles 16.1 to 16.6 and the valve 24. The line system 20 comprises a water pump 25, a pressure sensor 26, a flow meter 27 and a shut-off valve 28. Optionally, a filter 29 (in FIGS. 4 and 5) can further be integrated between the water pump 25 and the shut-off valve 28 in the set of lines of line system 20.

(14) The line system 20 further comprises a first line beam 17.1 and a second line beam 17.2. The first line beam 17.1 is connected in a fluidic manner via the valve 22 of the first fluid delivery apparatus 21 with the remaining part of the line system 20. The six large outlet nozzles 15.1 to 15.6 are further arranged on the line beam 17.1 in parallel. Once the valve 22 is opened, the fluid flows through the portion of the line system upstream of the valve 22 (driven by the pump 25) through the valve 22 into the line beam 17.1, and is distributed there among the individual outlet nozzles 15.1 to 15.6 and passes through the outlet nozzles 15.1 to 15.6 into the working chamber 10. The outlet nozzles 15.1 to 15.6 are thus dosing elements of the first fluid delivery apparatus 21. The second fluid delivery apparatus 23 has a similar configuration. In this case, the small outlet nozzles 16.1 to 16.6 are connected to the second line beam 17.2 which is in connection with the remaining part of the line system 20 via the valve 24 of the second fluid delivery apparatus 23. Once the valve 24 is opened and pump 25 is in operation, fluid is pumped through the line system 20 and through the valve 24 into the line beam 17.2 and leaves the same to enter the working chamber 10 via the individual dosing elements of the second fluid delivery apparatus 23 or through the outlet nozzles 16.1 to 16.6 which are also switched in parallel with each other. The large outlet nozzles 15.1 to 15.6 concern outlet nozzles with a fluid output of 25 L per minute per nozzle into the working chamber at an operating pressure of one bar (measured with the pressure sensor 26 in the line system 20) and an output of 60 L per minute fluid into the working chamber per nozzle at an operating pressure of five bars. The small nozzles 16.1 to 16.6 are arranged in the manner however that they supply 10 L of fluid per minute to the working chamber for each nozzle at an operating pressure of one bar and 25 L per minute at an operating pressure of five bars. The large and small outlet nozzles 15.1 to 16.6 are thus chosen in relation to one another in such a way that their respective output volumes supplement one another in a virtually overlap-free manner at a specific operating pressure from 1 to 5 bars.

(15) A further relevant element of the spraying device 18 is a control unit 30a. It is connected, as indicated by the broken and the dotted lines, with the pump 25, the pressure sensor 26, the flow meter 27, the shut-off valve 28, the valve 22 of the first fluid delivery apparatus 21 and the valve 24 of the second fluid delivery apparatus 23. The control unit 30 is arranged in the manner that it regulates and controls the output quantity of the fluid through the spraying device 18 and the first fluid delivery apparatus 21 and the second fluid delivery apparatus 23 into the working chamber 10. The control unit 30 is further arranged in the manner that it comprises an input field via which the operator can enter reference values, fluid properties, ground properties, etc., and general parameters relevant for the processing process. It is the principal idea of the present invention to arrange the spraying device 18 in the manner that it comprises at least two fluid delivery apparatuses (in the present case the first fluid delivery apparatus 21 and the second fluid delivery apparatus 23) with different output capacities concerning the flow rate of fluid per unit of time at a fixed operating pressure or comparative pressure and controls them in a manner adjusted to each other. If the introduction of large quantities of fluid into the working chamber 10 is desired, the control unit 30 opens the valve 22 of the first fluid delivery apparatus 21, so that in the present case 25 L of fluid per minute will be supplied per nozzle 25 to the working chamber 10 at an operating pressure of one bar for example in the line system 20. If on the other hand a lower fluid quantity is desired, the control unit 30 closes the valve 22 of the first fluid delivery apparatus 21, by means of which the introduction of fluid into the working chamber 10 through the large outlet nozzles 15.1 to 15.6 is deactivated. The control unit 30 opens the valve 24 of the second fluid delivery apparatus 23, so that the fluid will enter the working chamber 10 through the small outlet nozzles 16.1 to 16.3. If the operating pressure is one bar, 10 L of fluid per minute are introduced per nozzle into the working chamber. If the operating pressure is increased because the milling depth is increased for example and/or the working speed of the construction machine is increased, the control unit will switch over when reaching the threshold value of five bars from the second fluid delivery apparatus 23 with the small nozzles to the first fluid delivery apparatus 21 with the large nozzles and will lower the operating pressure accordingly, which occurs at first to one bar specifically in this case.

(16) In summary, the control unit 30a can adjust the feedback control process for controlling the spraying device 18 by taking measuring parameters into account, e.g., the milling depth and/or the travelling speed of the construction machine in this specific example. As a result, the control unit 30 can detect the milling depth and/or the travelling speed of the construction machine or the processing speed by means of suitable sensors and adjust the fluid output or the flow rate fluid per unit of time by regulating the pump 25 and/or the valves 22 and 24 of the first fluid delivery apparatus 21 or the second fluid delivery apparatus 23 to the travelling speed of the construction machine. Other measuring parameters can be the operating pressure of the fluid in the line system 20, the applied output of the pump 25, etc., for example.

(17) In order to obtain the maximum flow rate per unit of time of the spraying device 18 it is obviously also possible that the control unit activates both the first fluid delivery apparatus 21 and the second fluid delivery apparatus 23, so that fluid can be output simultaneously to the working chamber 10 through the outlet nozzles 15.1 to 15.6 and 16.1 to 16.6.

(18) It is therefore principally possible with the help of the control unit 30a and the spraying device 18a of FIG. 3 in combination with relatively low pressure fluctuations in the operating pressure (between one bar and five bars in the present case for example) to cover the flow rate of the fluid over a large range of desired conveying volumes (in the present case between 10 L per minute at an operating pressure of one bar and activated second fluid delivery apparatus 23 and deactivated first fluid delivery apparatus 21 up to 85 L per minute at five bars and activated first fluid delivery apparatus 21 and simultaneously activated second fluid delivery apparatus 23). Since extreme pressure ranges in the line system can be excluded in this manner at least in regular operation, it is ensured for example that and even quantity of fluid will be output from each outlet nozzle 15.1 to 15.6 or, depending on the activation state, 16.1 to 16.6 into the working chamber. At the same time, a certain minimum pressure can be ensured in operation on the outlet nozzles 15.1 to 15.6 to 16.1 to 16.6 over a wide range, by means of which clogging of the respective outlet nozzles by ground material can effectively be counteracted.

(19) A further embodiment of a spraying device 18b is shown in FIG. 4. Reference is hereby made to the statements in respect of the preceding embodiment concerning the principal configuration of the line system 20 and the dosing elements arranged as the outlet nozzles 15.1 to 15.6 and 16.1 to 16.6. The second fluid delivery apparatus comprises an additional dosing element 16.7, and therefore comprises the number of dosing elements of the first fluid apparatus +1.

(20) The relevant difference of the spraying device 18b in comparison with the spraying 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 preceding embodiment, the triggering of the individual outlet nozzles occurs in the present case individually and separate from one another, i.e., one by one, by the control unit 30b. Each of the dosing elements or outlet nozzles 15.1 to 15.6 and 16.1 to 16.7 comprises a respectively suitable valve which can be controlled and regulated by the control unit 30b, e.g., it can be opened and closed. The individual valves are not specifically stated in FIG. 4 for reasons of clarity of the illustration and are graphically a respective part of the respective outlet nozzle 15.1 to 15.6 and 16.1 to 16.7. The first fluid delivery apparatus 21 therefore comprises the totality of the individual large dosing elements or outlet nozzles 15.1 to 15.6, including their valves which are separately triggered by the control unit. The second fluid delivery apparatus 23 on the other hand designated the totality of the small dosing elements or outlet nozzles 16.1 to 16.7, including the valves which are not indicated separately in FIG. 4 and which are triggered by the control unit 30b.

(21) It is a further particularity of the spraying device 18b that both the dosing elements of the first fluid delivery apparatus 21 (outlet nozzles 15.1 to 15.6) and also the dosing elements of the second fluid delivery apparatus 23 (dosing elements 16.1 to 16.7) are arranged jointly on the line beam 17. The need for space in the rotational direction of the working roller in the working chamber 10 in the protective hood of the spraying device 18b is thus essentially lower for example than the need for space of the spraying device 18a with the two line beams 17.1 and 17.2 which are disposed behind one another in the rotational direction d of the working roller.

(22) It is further relevant in the spraying device 18b that individual dosing elements of the first fluid delivery apparatus 21 are distributed in an alternating manner in respect of the dosing elements of the second fluid delivery apparatus 23 over the entire length of the protective hood and are arranged to lie in one line in the axial direction of the rotational 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 in equal distances with respect to each other. If therefore all large outlet nozzles 15.1 to 15.6 and all small outlet nozzles 16.1 to 16.6 or even all outlet nozzles 15.1 to 15.6 and 16.1 610.6 are activated or are flowed through by fluid, the fluid will evenly distribute over the entire width of the working chamber 10. On the other hand, the individual triggering of individual outlet nozzles will enable the selective activation of a subgroup of the outlet nozzles 15.1 to 15.6 of the first fluid delivery apparatus 21 and/or the outlet nozzles 16.1 to 16.6 of the second fluid delivery apparatus 23. It is thus ensured that fluid is introduced into the working chamber 10 only over a part of the entire working width of the working roller 11. With reference to the entire working width, only a partial strip is supplied with fluid in working operation. In summary, the spraying device 18b therefore allows an exceptionally selective and individualized supply of fluid to the ground to be processed. It is further important that similar dosing elements 16.6 and 16.7 are arranged on the two outsides of the line beam 17 or in the axial direction of the working chamber (the direction in which the longitudinal axis 12 of the working roller extend in the working chamber). This feature also contributes to the homogeneous distribution of the fluid and the working chamber.

(23) A further difference finally lies in the arrangement of a filter 29 in the line system 20. The filter 29 is arranged in the direction of flow of the fluid behind the pump 25 or between the pump 25 and the line beam 17 or the branching of the line system before the line beam 17.

(24) A further embodiment of a spraying device 18c is shown in FIG. 5, which represents an especially tried and tested compromise between the spraying device 18a and 18b.

(25) The principal arrangement of the individual components of the spraying device 18c corresponds to that of the spraying device 18b (with the outer dosing element 16.7 missing in the spraying device 18c). The relevant difference is that the dosing elements 15.1 to 16.6 are switched in a grouped manner and are specifically grouped in pairs, and are triggered by the control unit 30c. As a result, the two outlet nozzles 15.1 and 15.2 form the dosing element group G1 for example, the outlet nozzles 15.3 and 15.4 the dosing element group G2, and the outlet nozzles 15.5 and 15.6 the dosing element group G3. The dosing element groups G1 to G3 (including the valves which are also not shown and are provided upstream of each outlet nozzle 15.1 to 15.6) jointly form the first fluid delivery apparatus 21. The dosing elements of the second fluid delivery apparatus 23 are also grouped in pairs. The outlet nozzles 16.1 and 16.2 form the dosing element group K1, the outlet nozzles 16.3 and 16.4 the dosing element group K2, and the outlet nozzles 16.5 16.6 dosing element group K3. The control unit 30c can now individually regulate and control the operating state of every single group G1, G2, G3, K1, K2 and K3 (indicated in FIG. 5 by the switching connections indicated in dotted and dashed lines of different thickness between the control unit 30c and the individual dosing elements 15.1 to 16.6). It is therefore also possible with the spraying device 18c to control individual segments of the first fluid delivery apparatus 21 and/or the second fluid delivery apparatus 23 individually and independent from one another concerning the operating state and the flow rate. At the same time, the switching of the control unit 30c with the individual fluid delivery apparatuses 21 and 23 can be simplified because it is not necessary that every single dosing element needs to be in contact with the control unit 30c via a single and individual signal connection, but merely the respective dosing element groups G1 to G3 and K1 to K3.

(26) FIG. 6 explains the functionality of the control process of the groups G1 to G3 and K1 to K3 of the spraying device 18c of FIG. 5. In respect of its fundamental principles this control process can also appropriately be applied to the spraying devices 18a and 18b. FIG. 6a) relates to the increase in the fluid volume introduced into the working chamber 10 by the spraying device 18 per unit of time (V1<V2). The timeline faces downwardly and is labeled with t. To the right of the V/t diagram are the dosing element groups G1 to G3 of the first fluid delivery apparatus 21 and K1 to K3 of the second fluid delivery apparatus 23. If a beam is present, the respective dosing element group G1 to G3 and K1 to K3 is activated and is flowed through by fluid or supplies fluid to the working chamber. If there is no beam under the respective dosing element group at a specific point in time, the respective dosing element group is deactivated or closed or does not supply fluid to the working chamber. The control of the activating states occurs via the control unit 30c.

(27) FIG. 6a illustrates in the left diagram that at time t1 the flow rate of the fluid volume to be delivered per unit of time into the working chamber is increased from volume V.sub.1 to volume V.sub.2 by control measures of the control unit 30c. The respective volume flow is increased from V.sub.1 to V.sub.2 from time t.sub.1 to time t.sub.2. At time t.sub.3, which lies between t.sub.1 and t.sub.2, a previously determined threshold value S.sub.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 to the large outlet nozzles or the dosing element groups G1 to G3. When exceeding the threshold value S.sub.W, the control unit thus switches over between the second fluid delivery apparatus 23 and the first fluid delivery apparatus 21. The relevant aspect in this step is that this changeover does not occur in an ad hoc manner at the time t.sub.3, but extends over a time t.sub.u which starts upon exceeding the threshold value S.sub.W. Both the originally activated second fluid delivery apparatus 23 which has not yet been deactivated and the first fluid delivery apparatus 21 which was newly activated by the control unit are activated jointly or in an overlapping manner over the time Δt.sub.u. The second fluid delivery apparatus 23 will only be the activated by the control unit after the expiration of the time window Δt.sub.u. If the fluid quantity to be dosed is reduced in working operation, the procedure as stated in FIG. 6a will occur in reverse sequence. Due to the fact that there is an overlapping range between the two fluid delivery apparatuses 21 and 23, the occurrence of pressure peaks in the line system 20 can be avoided during the changeover of the fluid delivery apparatuses 21 and 23, or it can at least be reduced to a substantial extent.

(28) The spraying device 18c of FIG. 5 further allows the individual triggering of two pairs of dosing elements or two pairs of outlet nozzles which are combined by circuitry as groups G1, G2, G3, K1, K2 or K3. This is illustrated in FIG. 6a by the tracks of groups G1 and K1 which are colored in black. In addition to the joint activation with the additional two groups colored in grey, it is thus possible for example to provide the singular activation and changeover between the groups K1 and G1.

(29) FIG. 6b finally illustrates the control of the spraying device 18c by the control unit 30c of FIG. 5 by taking into account the travelling speed v of a respectively equipped construction machine. The travelling speed is provided merely as an example for illustrating the principal functionality. Alternatively or additionally, it is also possible to use the milling depth, changing ground properties, the flow rate, etc., for regulation in order to ensure a continuous distribution of the fluid in the ground material to be processed. The left diagram according to FIG. 6b therefore shows the speed v or the speed curve of the construction machine.

(30) At the time t.sub.1 the machine will accelerate and exceed the threshold value S.sub.W. The control unit 30c will trigger a changeover from the dosing element group K1 to K3 of the second fluid delivery apparatus 23 to the dosing element groups G1 to G3 of the second fluid delivery apparatus 21, similar to the process of FIG. 6a, in order to enable the desired introduction of fluid into the ground material to be processed if at higher working speeds. For reasons of clarity of the illustration, the progression of the volume flow is not shown in closer detail in FIG. 6b. In the end, it extends parallel to the development of the travelling speed. The fluid quantity delivered by the spraying device 18c to the working chamber will rise with increasing travelling speed and vice versa. It is thus ensured that a constant quantity of fluid is introduced into the ground material to be processed even at different travelling speeds.

(31) Finally, at the time t.sub.4 the construction machine will accelerate up to the time t.sub.5 and will exceed the maximum value M.sub.W at the time t.sub.6. The maximum value is based on the maximum delivery quantity of the fluid into the working chamber with the help of the more powerful fluid delivery apparatus 21. In order to ensure a sufficient supply of the working chamber with fluid in working operation even at maximum travelling speed, the control unit will activate the dosing element groups K1 to K3 of the second fluid delivery apparatus 23 in addition to the first fluid delivery apparatus 21 when exceeding the maximum value M.sub.W, so that both fluid delivery apparatuses 21 and 23 are operated in parallel thereafter. If the working speed of the construction machine is then decreased at the time t.sub.7 up to the time t.sub.8, the travelling speed decreases at first beneath the maximum value M.sub.W at the time t.sub.9 and beneath the threshold value S.sub.W at the time t.sub.10. When falling beneath the maximum value M.sub.W, the control unit at first deactivates the fluid delivery of the dosing element groups K1 to K3 of the second fluid delivery apparatus 23. When falling beneath the threshold value, the control unit switches over from the dosing element groups G1 to G3 of the first fluid delivery apparatus 21 to the dosing element groups K1 to K3 of the second fluid delivery apparatus, with the changeover occurring in an overlapping manner over the time interval Δt.sub.u in order to prevent pressure peaks in the line system.

(32) It is understood that it is also possible to provide a control of the spraying device 18c which is adjusted to the travelling speed in a selective manner with one or two dosing element groups of the first fluid delivery apparatus 21 and/or the second fluid delivery apparatus 23. This is illustrated in FIG. 6b by the respective middle dosing element group G2 and K2, which are each colored in black.

(33) No further regulation processes are provided either in FIG. 6a or in FIG. 6b which are controlled and regulated by the control unit 30c. This relates for example to the regulation of the pumping output, the pumping speed, checking the line pressure, etc.

(34) While the present invention has been illustrated by description of various embodiments and while those embodiments have been described in considerable detail, it is not the intention of Applicants to restrict or in any way limit the scope of the appended claims to such details. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of Applicants' invention.