Civil engineering installation and method for operating civil engineering installation

Abstract

The invention relates to civil engineering equipment, which is provided with a supporting device; a processing unit configured to perform civil engineering steps and held on the support means by at least one cable; at least one cable capstan for operating a cable, wherein the cable capstan has a capstan drum and an associated capstan motor; and at least one free fall brake arranged on the at least one cable winch. According to the invention, it is provided that: the electronic control device is arranged for controlled opening, partial opening and closing of the freefall brake; the descending speed and / or the descending path can be preset to target values in the control device; arranging at least one detection device configured to detect a descent speed and / or a descent path of the processing unit as an actual value; and a control device connected to the at least one detection device and configured to control opening, partial opening, and closing of the free-fall brake according to the detected actual value such that the actual value approaches a preset target value.

Description

Technical Field

[0001] According to the preamble of claim 1, the present invention relates to a civil engineering device, in particular a cable grabber, comprising: a supporting device; a processing unit, which is configured to perform civil engineering steps and is held on the supporting device by at least one cable; at least one cable winch for operating the cable, wherein the cable winch has a winch drum and an associated winch motor for rotationally driving the winch drum; at least one free fall brake, which is arranged on the at least one cable winch, wherein in a closed state of the free fall brake, the winch drum is coupled to the associated winch motor; in a partially opened state of the free fall brake, a relative movement between the winch drum and the winch motor is possible, wherein a torque is transmitted in the free fall brake, which torque depends on the degree of opening of the free fall brake; and in an open state, the winch drum is decoupled from the associated winch motor and can rotate essentially freely relative to the associated winch motor. Background Art

[0002] In the case of certain civil engineering equipment, in particular so-called cable grabbers, it is often necessary to repeatedly lower and raise the processing unit by means of a cable using a cable winch in order to carry out the civil engineering step. In the case of a cable grabber or a drilling bucket, for example, as a processing unit, it is necessary to pull the cable grabber or drilling bucket filled with removed ground material out of the hole formed in the ground again after the civil engineering step and move it to a discharge point for discharge. The processing unit is then moved back into the drill hole for the restarted processing step.

[0003] In order to carry out this process efficiently, the aim in this case is to carry out the raising and in particular the lowering of the treatment unit as quickly as possible.

[0004] For example, EP 4134489 A1 shows a civil engineering device with a cable grabber. In the case of a cable grabber, it is known to lower the grabber by frictionally actuating and driving a cable winch in the descending direction or by partially or completely opening a so-called free fall brake due to the deadweight of the cable grabber. In all cases, this is carried out manually by the machine operator.

[0005] By lowering by friction with the capstan driven in rotation in the lowering direction, it is in principle possible to control the lowering speed. However, due to the maximum possible speed of the capstan motor, only a limited lowering speed can be achieved.

[0006] On the other hand, when the cable grabber is lowered with the winch drive fully or partially decoupled, a much greater lowering speed can be achieved due to the fully or partially opened free fall brake. However, the machine controller cannot control the movement. When the cable grabber is lowered in free fall, the machine operator must always stand on the control pedal of the free fall brake in order to control the lowering speed by means of the pedal position. In this case, it is not easy to find the correct pedal position. This depends largely on the experience of the machine operator. In addition, it is ergonomically difficult to operate the control pedal or brake pedal for a long time to control the descent.

[0007] In particular, the machine controller has no control over the maximum descent speed and descent path. This will be controlled by the machine operator based on his or her experience. In the past, this has repeatedly led to damage to the free fall brakes, as they can overheat, especially in the case of long descent paths, high descent speeds and heavy cable grabbers.

[0008] The problem is that when descending in free fall, the winch motor is stationary. This means that the plate in the free fall brake connected to the winch motor is stationary, while the plate connected to the winch drum rotates according to the descent speed of the cable grabber. For a descent with the free fall brake partially open, this means that the plate pairs in the free fall brake rub against each other. This leads on the one hand to wear of the plates and on the other hand to heating of the free fall brake, which can lead to overheating of the free fall brake. Summary of the invention

[0009] The object of the invention is to specify a civil engineering device and an operating method by means of which a handling unit on a civil engineering device can be lowered particularly efficiently.

[0010] According to the invention, this object is achieved on the one hand by a civil engineering device having the features of claim 1 and on the other hand by a method having the features of claim 11. Preferred embodiments of the invention are indicated in the respective dependent claims.

[0011] The civil engineering equipment according to the present invention is characterized in that: an electronic control device is arranged for the controlled opening, partial opening and closing of the free fall brake by means of at least one control element; the descent speed and / or the descent path can be preset as a target value in the control device; at least one detection device is arranged, and the at least one detection device is configured to detect the descent speed and / or the descent path of the processing unit as an actual value; and the control device is connected to the at least one detection device and is configured to control the opening, partial opening and closing of the free fall brake according to the detected actual value, so that the actual value is close to the preset target value so as to correspond to these preset target values.

[0012] The basic idea of ​​the present invention is to open, partially open and close the free-fall brake in an inventive manner controlled by an electronic control device. For this purpose, at least one controllable control element for opening, partially opening and closing is arranged on the free-fall brake.

[0013] According to another aspect of the invention, target values ​​are stored in the control device, which values ​​are at least related to the descent speed or the descent path. The actual value corresponding to the target value, and thus at least the actual descent speed or the actual descent path, can be detected by means of at least one detection device. The descent speed can be detected directly or indirectly via a corresponding value of the rotation speed of the cable winch, for example. Accordingly, the descent path of the processing unit can also be detected directly or indirectly, for example via the number of revolutions or the rotational position of the free fall winch.

[0014] According to another aspect of the invention, the control device is configured so that the opening, partial opening and closing of the free fall brake is controlled according to the detected actual value so that the actual value approaches the preset target values ​​so as to ideally correspond to these preset target values. It can be said that automatic control of the free fall brake is achieved according to the actual data of the processing unit.

[0015] Thus, using the civil engineering device according to the invention, a highly automated free-fall operation can be realized for lowering the handling unit. Here, on the one hand, the advantages of energy saving and, in particular, rapid descent in free-fall mode can be achieved. On the other hand, due to the automation of the control of the opening, partial opening and closing of the free-fall brake, the burden on the machine operator is significantly relieved, since it is no longer necessary to operate the control pedal or the brake pedal for a long time. The process can be controlled by the machine as a whole.

[0016] A preferred embodiment of the invention is that the at least one winch motor is controlled by the control device and that the control device is configured to operate the associated winch motor when the free fall brake of the cable winch is opened or partially opened so as to rotationally drive the winch drum in the direction of descent of the cable. According to this continuous configuration, the control device also controls the winch motor. The control device is in particular configured so that when the free fall brake of the cable winch is opened or partially opened, the associated winch motor is also operated in the direction of lowering the cable. However, this seemingly contradictory operation of the winch motor for lowering while the free fall brake is opened or partially opened and the winch drum is therefore at least partially decoupled from the winch motor has the following advantages: due to the reduced speed difference between the plate pairs in the free fall brake, the wear on the plates of the free fall brake and the heat generation in the free fall brake are reduced.

[0017] Furthermore, slippage may occur between the plate connected to the winch motor and the plate connected to the winch drum. The descent speed may be altered by this slippage. Furthermore, when the winch motor is already running in the descent direction, the free fall brake may be opened more slowly, which may also lead to a softer descent in this start-up phase and reduce wear on the plate.

[0018] According to a development of the invention, it is advantageous if the control device has at least one input device for entering the lowering speed and / or the lowering path as a target value and / or a control command. The input device can be configured in essentially any manner, in particular as a keyboard, a touch screen, or via a suitable rotary switch. This enables the machine operator to specify and set the respective desired value for each construction measure.

[0019] According to another embodiment variant of the invention, it is preferred that the control device is configured with an automatic control program, wherein upon input of a start and / or stop command, the free fall operation of the at least one free fall winch is started or stopped, respectively, by gradually opening or partially opening or closing the free fall brake, respectively, within a preset time span. Upon starting or stopping, respectively, by gradually opening or partially opening and closing the free fall brake within a preset time span, a particularly gentle operation can be achieved, which has a positive effect on the service life of individual components and of the entire civil engineering equipment.

[0020] A particularly preferred embodiment is also that the input device of the control device comprises a joystick which is tiltable, wherein the lowering speed can be controlled by the operator via the tilt angle of the joystick. Thus, a particularly simple and low-effort control of the lowering speed can be achieved by means of one-handed operation of the joystick. Speed ​​control by means of the joystick by tilting the joystick also facilitates a particularly intuitive speed adjustment.

[0021] Another advantageous embodiment of the invention is that the input device of the control device has a control button, in particular a control button on a joystick, for starting and stopping the automatic control program. In this way, the winch can initially be controlled manually via the joystick, in particular with regard to the lowering speed, wherein the machine operator can switch to automatic operation by a simple actuation of the control button. Further control of the lowering speed and, if applicable, the lowering path can take place in this way via the automatic control program. The control button is preferably arranged directly on the joystick so that the lowering can take place in an ergonomically reasonable manner with one-handed operation.

[0022] In principle, the free-fall brake can be configured in any suitable manner. According to an embodiment variant of the invention, it is particularly advantageous if at least one free-fall brake is configured as a multi-plate clutch with several friction plates (also called plates) which can be pressed against one another for braking. The free-fall brake is constructed in the manner of a multi-plate clutch such that the contact and friction surface increases according to the number of plates arranged. This permits a particularly high force transmission.

[0023] By axially pressing against each other, the plates are connected to each other by force fit or friction engagement, so that a force transmission is achieved between them. In particular, a winch drum connected to a plate on a first side can thus be connected in a torsion-proof manner to a winch motor or a retaining element, which is connected to the opposite plate on a second side. By appropriately slow axial adjustment of the plates relative to each other, a correspondingly gentle braking effect can be achieved.

[0024] According to a development of the invention, it is provided that the civil engineering device has a cable grabber with a grabber spade, in particular as a partition wall grabber with an approximately rectangular guide frame or as a drilling rig clamp with an approximately cylindrical guide frame, and that scraping teeth are arranged on the grabber spade, which scraping teeth are configured to scrape soil.

[0025] The cable grabber may be connected via corresponding cable suspension means on the mast or boom arm to a support device on which the winch is arranged. The support device may preferably be movable and in particular comprise a tracked undercarriage.

[0026] According to a further embodiment of the invention, the cable grabber advantageously has a first cable for raising and lowering the cable grabber and a second cable for opening and closing the grabber shovel, and the two cables can each be operated by a cable winch. The cable winch is preferably arranged on the support device. This permits a particularly compact construction of the civil engineering apparatus.

[0027] The method of the present invention for operating civil engineering equipment is characterized by: using the civil engineering equipment of the present invention; controlling the opening and closing of at least one free-fall brake with the aid of an electronic control device and with the aid of at least one control element; presetting the descent speed and / or the descent path as a target value in the control device; detecting the descent speed and / or the descent path of the processing unit as an actual value with the aid of a detection device; and based on the detected actual value, controlling the opening, partial opening and closing of the free-fall brake with the aid of the control device so that the actual value is close to the preset target value.

[0028] The method according to the invention can be carried out in particular with the aid of the previously described civil engineering equipment according to the invention. In doing so, the advantages described previously can be achieved. In particular, the previously described civil engineering equipment can also be operated according to the method according to the invention.

[0029] The civil engineering device can in principle be configured to carry out any civil engineering method. According to the continuous configuration of the invention, it is particularly preferred that soil is removed by means of the civil engineering device. The soil removal can in particular take place in a discontinuous process.

[0030] One embodiment variant of the invention consists in using a civil engineering device with a cable grabber, wherein a trough with a rectangular trough cross section or a hole with a circular hole cross section is formed by means of the cable grabber. When the hole is formed in the ground, the ground material can be received in the cable grabber by opening and closing the grabber shovel. The filled cable grabber can be pulled out of the hole and moved to the discharge point. After discharge, the cable grabber can be returned to the handling point again by corresponding operation of the cable winch and lowered into the hole. In particular, the lowering can take place according to the method of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention is further explained below based on preferred exemplary embodiments, which are schematically illustrated in the accompanying drawings. In the accompanying drawings:

[0032] Figure 1 A perspective view of the civil engineering apparatus of the present invention with a cable grabber is shown;

[0033] Figure 2 Shows Figure 1 A front view of a cable grabber of a civil engineering apparatus of the type shown in FIG. 1 , wherein the cable grabber has a closed grabber scoop;

[0034] Figure 3 Shown according to Figure 2 A front view of a cable grabber with an open grabber scoop; and

[0035] Figure 4 A schematic cross-sectional representation of a winch arrangement with a free-fall brake for civil engineering equipment according to the invention is shown. DETAILED DESCRIPTION

[0036] according to Figure 1 The civil engineering device 10 according to the invention can have a mobile support 12 with a crawler chassis as a chassis 14. An upper carriage 16 with an operator's cabin 17 can be rotatably supported on the chassis 14 about a vertical rotation axis. A control device is preferably located inside the operator's cabin 17, which control device includes an input device for the machine operator.

[0037] The boom arm 18 may be pivotably hinged on the upper carriage 16 about a horizontal axis. A holding cable 24 may be guided at the head 20 of the boom arm 18 by means of a deflection pulley, at the end of which a handling unit 30 configured as a cable grabber 31 with a grabber frame 32 and a lower grabber scoop 34 may be attached. The holding cable 24 may be operated via a first cable winch 21 on the support device 12 in order to raise and lower the cable grabber 30. Furthermore, a second cable winch 22 may be located on the support device 12 for an operating cable 44, which may likewise be guided via the head 20 to the cable grabber 30 in order to operate the grabber scoop 34 at the lower end of the grabber frame 32.

[0038] Combined with the following Figure 2 and Figure 3 The mode of operation of the civil engineering device 10 of the present invention will be explained in more detail.

[0039] In the center area of ​​the grabber frame 32, an operating carriage 42 of an operating device 40 for operating the grabber scoop 34 can be displaceably supported in the vertical longitudinal direction. The end of the holding cable 24 can be attached at the upper end of the operating carriage 42 so that the cable grabber 31 is held via the operating carriage 42.

[0040] A linkage 46 with a linkage 47 can be arranged at the lower end of the operating carriage 42. The linkage 47 is preferably articulatedly connected to the operating carriage 42 on the one hand and to one of the grabber scoops 34 on the other hand. The grabber scoop 34 itself can be pivotally supported at the lower end of the grabber frame 32 by a pivot bearing 35. The grabber scoop 34 can be opened and closed by a relative displacement of the operating carriage 42 relative to the grabber frame 32. The linkage 47 can be pulled upwards by a relative displacement of the operating carriage 42 upwards, wherein the grabber scoop 34 is pivoted into its open position about its pivot axis 35, which is clearly shown in FIG. Figure 3 middle.

[0041] A block and tackle arrangement 50 for an operating cable 44 may be provided below the operating carriage 42. The block and tackle arrangement 50 may have an upper pulley 52 rotatably supported on the operating carriage 42 and a lower pulley 54 rotatably supported on a lower region of the grabber frame 32. The pulleys 52, 54 may be wound multiple times by the operating cable 44 supplied from above, thereby forming a winding 56 or length, wherein the lower end of the operating cable 44 is fixedly connected to the grabber frame 32. Thus, the operating carriage 42 may be adjustably connected or coupled to the grabber frame 32 by the operating cable 44.

[0042] From the basis Figure 3Starting from the open position, the operating carriage 42 can be pulled downward relative to the grabber frame 32 by the pulley block device 50 by pulling the operating cable 44 upward by the second cable winch 22. As a result, the connecting rod 47 presses the grabber scoop 34 downward with an increased closing force, wherein the grabber scoop 34 pivots about its pivot bearing 35 to the position according to Figure 2 closed position.

[0043] During use, in the groove in the ground, soil material may be grabbed with an increased closing force compared to the tension on the operating cable 44 in the process and may be enclosed between the grabber scoops 34 .

[0044] After the cable grabber 31 has been pulled out of the slot in the ground and after it has been moved to the unloading position, the tension on the operating cable 44 can be reduced. In this way, the grabber frame 32 can move downward relative to the operating carriage 42 due to its weight, so that the grabber shovel 34 pivots back to its open position via the connecting rod 47, as shown in FIG. Figure 3 As shown in .

[0045] The arrangement described here is only an example. In principle, other pulley block arrangements with different cable couplings and different linkages can also be selected, which facilitate comparable grabber shovel operation.

[0046] When operating the cable grabber 31, it is necessary to coordinate the forces and movements between the holding cable 24 and the operating cable 44 so as to take into account the so-called laying direction, in particular in the case of a wound cable, to control the torque in the individual cables and therefore the torque of the attached cable grabber 31 about its longitudinal axis, so that the desired rotation of the cable grabber 31 only occurs when the construction sequence requires it.

[0047] The forces in the holding cables 24 and the operating cables 44 can be detected by suitable detection devices, which can be arranged, for example, on the cable winches 21, 22 or on the deflection pulleys at the head 20 of the boom arm 18. Via a control device preferably arranged in the operator cabin 17 on the support device 12, the winches 21, 22 can be controlled according to the detected cable forces, so that the stability of the pivot orientation of the cable grabber 31 around its longitudinal axis or the targeted twisting desired by the machine operator can be achieved. For the machine operator, only the appropriate input of the compensation mode, which is optionally desired for position stability, or the input of the desired rotational position of the cable grabber 31 is required. Based on this, the control device can activate the cable winches 21, 22 accordingly to achieve the desired pivot orientation of the cable grabber 31. As a result, the control of the simply constructed cable grabber 31 is significantly simplified and becomes easier for the machine operator.

[0048] After the unloading of the grabber shovel 34, the cable grabber 31 can be lowered again into the hole in the ground. This can take place in a controlled free fall mode, as described below in conjunction with Figure 4 The winch device explains this.

[0049] according to Figure 4 An exemplary winch arrangement of has a cable winch 60 having a winch drum 62 which may be rotatably mounted on a winch frame 64. The winch drum 62 is rotationally driven by a schematically shown winch motor 70 (which may be implemented as a hydraulic motor) via a drive shaft 71 and a schematically shown winch gear 72 (which may be a single-stage or multi-stage planetary gear). The cable winch 60 may form at least one or two winches 21, 22 of the previously described civil engineering equipment 10.

[0050] According to the invention, a free fall brake 80 is arranged between the winch motor 70 and the winch drum 62, the free fall brake 80 being constructed in the manner of a multi-plate clutch or a multi-plate brake. By operating the free fall brake 80, on the one hand, a torsion-proof coupling can be achieved between the winch motor 70 and the winch drum 62, in particular a torsion-proof coupling with the drive shaft 71 of the winch drum 62, and on the other hand, a decoupled or partially decoupled state can be achieved. In the decoupled state, the winch drum 62 of the cable winch 60 can rotate freely without the presence of a torsion-proof connection to the winch motor 70. By gradually adjusting the plates of the free fall brake 80, an intermediate state between the coupled state and the decoupled state can also be set, wherein a certain slip can occur between the winch motor 70 and the winch drum 62, which in turn achieves friction between the plate pairs of the free fall brake 80.

[0051] The holding and locking of the winch drum relative to the winch frame 64 can take place by means of the holding brake 84. According to the invention, a control device 90 is arranged for control, which device can be formed, for example, by a computer or other electronic control unit. The activation of the winch motor 70, in particular with regard to speed, torque, rotational position, etc., can take place via the control device 90. Furthermore, the control device 90 can be configured with a first actuator 91 for opening, partially opening and closing the free fall brake 84. The holding brake 84 can be operated by the control unit 90 via a second actuator 92.

[0052] The machine operator can enter target values ​​into the control device 90 for the lowering speed or respectively the rotation of the winch drum 62 and / or the lowering path of the processing unit 30. Furthermore, the machine operator can activate the winch motor 70 and the free fall brake 84 via the control device 90. In particular, a joystick 97 is provided as an input device 96 of the control device 90, by means of which the machine operator can control the lowering speed of the processing unit 30 attached to the cable winch 60 by tilting the joystick. By means of a control button 98 on the joystick 97, the machine operator can activate or deactivate an automatic program.

[0053] The rotational position and / or speed of the winch drum 62 can be detected via the detection device 94 and forwarded to the control device 90 as actual values ​​for the descent speed and / or descent path of the attached processing unit 30. The corresponding data can be found at Figure 4 The information is displayed to the machine operator on a monitor (not shown).

[0054] After activation of the automatic control program, automatic operation of the free fall brake 84 by the control device 90 can take place so that the actual value detected by the detection device 94 corresponds to preset target values ​​regarding the descent speed or descent path, respectively, or is at least close to these preset target values.

[0055] In case of a handling unit 30 such as a cable grabber 31 with two cables 24, 44, both winches 21, 22 can be activated simultaneously to cause a lowering of the handling unit 30 or respectively the cable grabber 31 without opening or closing the grabber scoop 34 respectively.

Claims

1. A civil engineering device, in particular with a cable grabber (31), comprising: - a supporting device (12), a processing unit (30) configured to perform a civil engineering step and held on the support device (12) by at least one cable (24, 44), - at least one cable winch (60) for operating the cable (24, 44), wherein the cable winch (60) comprises a winch drum (62) and an associated winch motor (70) for rotationally driving the winch drum (62), a free fall brake (80) arranged on the one cable winch (60), wherein in a closed state of the free fall brake (80), the winch drum (62) is coupled to the associated winch motor (70); in a partially open state of the free fall brake (80), a relative movement between the winch drum (62) and the winch motor (70) is possible, wherein a torque depending on the degree of opening of the free fall brake (80) is transmitted in the free fall brake (80); and in an open state, the winch drum (62) is decoupled from the associated winch motor (70) and can rotate substantially freely relative to the associated winch motor (70), It is characterized in that - an electronic control device (90) is arranged for controlled opening and closing of the free-fall brake (80) by means of at least one actuator (91), - the descent speed and / or the descent path can be preset as a target value in the control device (90), at least one detection device (94) is arranged, which is configured to detect the descent speed and / or the descent path of the processing unit (30) as actual values, and - the control device (90) is connected to the at least one detection device (94) and is configured to control the opening, partial opening and closing of the free fall brake (80) according to the detected one or more actual values ​​so that the actual value approaches the preset target value.

2. The civil engineering equipment according to claim 1, It is characterized in that The at least one winch motor (70) is controlled by the control device (90), and The control device (90) is configured to operate the associated winch motor (70) in a descending direction when the free fall brake (80) of the cable winch (60) is opened or in particular partially opened.

3. Civil engineering equipment according to claim 1 or 2, It is characterized in that The control device (90) has at least one input device (96) for inputting the descent speed and / or the descent path as a target value and / or for inputting a control command.

4. Civil engineering equipment according to any one of claims 1 to 3, It is characterized in that The control device (90) is configured with an automatic control program, wherein upon input of a start and / or stop command, the free fall operation is started or stopped respectively by gradually opening / partially opening or closing the free fall brake (80) respectively within a specified time span.

5. Civil engineering equipment according to claim 3 or 4, It is characterized in that The input device (96) of the control device (90) comprises a joystick (97) which is tiltable, wherein the descent speed can be controlled by an operator via the tilt angle of the joystick (97).

6. Civil engineering equipment according to any one of claims 3 to 5, It is characterized in that The input device (96) of the control device (90) has a control button (98), in particular a control button (98) on a joystick (97), for starting and stopping an automatic control program.

7. Civil engineering equipment according to any one of claims 1 to 6, It is characterized in that The free fall brake (80) is configured in the manner of a multi-plate clutch having a plurality of friction plates which can be pressed against each other for braking.

8. Civil engineering equipment according to any one of claims 1 to 7, It is characterized in that It has a cable grabber (31) with a grabber scoop (34), in particular as a partition wall grabber with an approximately rectangular guide frame (32) or as a drilling rig grabber with an approximately cylindrical guide frame; and A scraper tooth is disposed on the grabber blade (34), the scraper tooth being configured to scrape soil.

9. Civil engineering equipment according to claim 8, Features The cable grabber (31) has a first cable (24) for raising and lowering the cable grabber (31) and a second cable (44) for opening and closing the grabber scoop (34); and The two cables (24, 44) are each operable by a cable winch (60).

10. Civil engineering equipment according to any one of claims 1 to 9, Features A plurality of cables (24, 44) are each arranged with a cable winch (60) which can be actuated in parallel or synchronously with each other.

11. A method for operating civil engineering equipment (10), It is characterized in that - use of a civil engineering device (10) according to any one of claims 1 to 10, - controlling the opening and closing of the at least one free-fall brake (80) by means of an electronic control device (90) by means of at least one control element (92), - the descent speed and / or the descent path can be preset as a target value in the control device (90), - detecting the descent speed and / or the descent path of the processing unit (30) as an actual value by means of at least one detection device (94); and - According to the detected actual value, the opening and closing of the free fall brake (80) is controlled by means of the control device (90) so that the actual value approaches the preset target value.

12. The method according to claim 11, It is characterized in that The soil is removed by means of the civil engineering device (10).

13. The method according to claim 11 or 12, It is characterized in that A civil engineering device (10) is used with a cable grab (31), wherein a slot with a rectangular slot cross section or a hole with a circular hole cross section is formed by means of the cable grab (31).

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