Civil engineering machine, and method for operating civil engineering machine

Abstract

To specify a civil engineering machine and a method for operating the same in which a work unit of the civil engineering machine can be lowered particularly efficiently.SOLUTION: In a civil engineering machine, an electronic control device is provided for controlled opening, partial opening and closing of a free fall brake by means of at least one control element, a lowering speed and / or a lowering path can be preset as target values in the control device, at least one detection device is provided which is configured to detect a lowering speed and / or a lowering path of the work unit as actual values, and the control device is connected to the at least one detection device and is configured to control opening, partial opening and closing of the free fall brake depending on the detected actual values. Thus, the actual values approximate to the preset target values in order to correspond to them.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The invention relates to an earth moving machine, in particular a cable grab, comprising a support device, a working unit configured to perform an earth moving process and held on the support device by means of at least one cable, at least one cable winch for manipulating the cable, the cable winch having a winch drum and an associated winch motor for driving the winch drum in rotation, and at least one free fall brake arranged on the at least one cable winch, such that in a locked state of the free fall brake the winch drum is coupled to the associated winch motor, in a semi-released state of the free fall brake a relative movement is possible between the winch drum and the winch motor, a torque is transmitted in the free fall brake, which torque corresponds to a degree of release of the free fall brake, and in a released state the winch drum is decoupled from the associated winch motor and is substantially freely rotatable relative to it, as defined in the preamble of claim 1. [Background technology]

[0002] In the case of certain earthmoving machines, in particular so-called cable grabs, it is frequently necessary to repeatedly lower and raise the working unit for carrying out the earthmoving process by means of a cable winch via a cable. For example, in the case of a cable grab or a digging bucket as the working unit, after the earthmoving process, the cable grab or the digging bucket, filled with the soil removed from the ground, must be lifted again from the hole made in the ground and moved to a discharge point where it is emptied. The working unit is then returned again to the hole for a new working process.

[0003] In order to carry out the work efficiently, the aim here is to carry out the raising and, in particular, the lowering of the working unit as quickly as possible.

[0004] For example, patent document 1 shows a construction machine with a cable grab. In the case of the cable grab, it is known to lower it by friction actuation and driving the cable winch in the downward direction or by the weight of the cable grab by fully releasing or partially releasing (semi-releasing) the so-called free-fall brake. In all cases, this is done manually by the machine operator.

[0005] In friction descent by rotating the winch in the downward direction, it is possible in principle to control the descent speed, but only a limited descent speed can be achieved due to the maximum possible speed of the winch motor.

[0006] On the other hand, when the cable grab is lowered with the winch drive fully or partially disengaged, a much faster descent speed can be achieved by fully or half releasing the free-fall brake. However, there is no control of the movement by the machine controller. When the cable grab is lowered in free fall, the machine operator must keep standing on the control pedal of the free-fall brake to control the descent speed through the pedal position. In this case, it is not easy to find the correct pedal position. This depends heavily on the experience of the machine operator. Moreover, operating the control pedal or the brake pedal for controlling the descent for a long time is ergonomically burdensome.

[0007] In particular, there is no control by the machine controller regarding the maximum descent speed, nor the descent path. This is controlled by the machine operator according to his own experience. In the past, this has repeatedly caused damage to the free-fall brake, especially in the case of long descent paths, fast descent speeds, and heavy cable grabs, as the free-fall brake can overheat.

[0008] The problem is that when descending in free fall, the winch motor is stationary. This means that the plates of the free fall brake connected to the winch motor are stationary, while the plates connected to the winch drum are rotating according to the descent speed of the cable grab. When descending with a half-released free fall brake, this means that the plate pairs in the free fall brake rub against each other. This causes wear of the plates on the one hand and heating of the free fall brake on the other hand, which can lead to overheating of the free fall brake. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] European Patent Application Publication No. 4134489 Summary of the Invention [Problem to be solved by the invention]

[0010] The object of the invention is to specify an earth-moving machine and a method for operating it, which allows a working unit of the earth-moving machine to be lowered particularly efficiently. [Means for solving the problem]

[0011] This object is achieved according to the invention on the one hand by a civil engineering machine 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 set out in the respective dependent claims.

[0012] The civil engineering machine according to the present invention is characterized in that an electronic control device is arranged for controlled release, semi-release and arrestment of the free-fall brake by means of at least one control element, the descent speed and / or the descent path can be preset in the control device as a setpoint value, at least one detection device is arranged and configured to detect the descent speed and / or the descent path of the working unit as an actual value, and the control device is connected to the at least one detection device and configured to control the release, semi-release and arrestment of the free-fall brake depending on the detected actual value, so that the actual value approaches the preset setpoint value so that it corresponds to the setpoint value.

[0013] The basic idea of ​​the invention is to release, semi-release and lock a free-fall brake in an inventive manner controlled by an electronic control device, for this purpose the free-fall brake is arranged with at least one controllable control element for releasing, semi-release and locking.

[0014] According to another aspect of the invention, a setpoint value is stored in the control device, which value is related to at least the descent speed or the descent path. An actual value corresponding to the setpoint value, and thus at least the actual descent speed or the actual descent path, can be detected by at least one detection device. The descent speed can be detected directly or indirectly via a corresponding value, for example the rotation speed of the cable winch. Similarly, the descent path of the working unit can also be detected directly or indirectly, for example via the number of rotations or the rotation position of the free-fall winch.

[0015] According to another aspect of the invention, the control device is configured to control the release, partial release and locking of the free-fall brake depending on the detected actual value, so that the actual value approaches the preset target value so that it ideally coincides with the target value, so that an automatic control of the free-fall brake depending on the actual data to the working unit is realized, so to speak.

[0016] Thus, by using the earthmoving machine according to the invention, a largely automated free-fall operation can be implemented for lowering the working unit, which on the one hand has the advantage of being energy-efficient and particularly fast in free-fall mode, and on the other hand, the automated control of the release, half-release and restraint of the free-fall brakes significantly reduces the burden on the machine operator, since no long-term control or brake pedal operation is required. This process can be controlled by the entire machine.

[0017] A preferred embodiment of the invention is that at least one winch motor is controlled by a control device, and that the control device is configured to operate the associated winch motor when releasing or partially releasing the free-fall brake of the cable winch in order to rotate and drive the winch drum in the direction of cable downwards. According to this further configuration, the control device also controls the winch motor. The control device is particularly configured to operate the associated winch motor when releasing or partially releasing the free-fall brake of the cable winch in the direction of cable downwards. This seemingly contradictory operation of the winch motor to release or partially release the free-fall brake and simultaneously lower the winch drum at least incompletely from the winch motor, however, has the advantage that the speed difference between the plate pairs of the free-fall brake is reduced, thereby reducing wear on the plates of the free-fall brake and heat generation in the free-fall brake.

[0018] Furthermore, slippage can be created between the plate connected to the winch motor and the plate connected to the winch drum, which can vary the speed of descent. In addition, the free-fall brake in particular can be released slowly while the winch motor is already moving in the downward direction, which can also make the descent gentler during this initial phase and reduce wear on the plates.

[0019] According to a development of the invention, it is advantageous if the control device has at least one input device for inputting the lowering speed and / or the lowering path as target value and / or control command. The input device can be configured in basically any form, in particular as a keyboard, as a touch screen or by suitable rotary switches. This allows the machine operator to specify and set the respectively desired values ​​for each application means.

[0020] According to another implementation variant of the invention, the control device is preferably configured with an automatic control program, in which, when a start and / or stop command is input, the free-fall operation of the at least one free-fall winch is started or stopped by gradually releasing or semi-releasing or binding the free-fall brake over a preset period in response to the start / stop command. By gradually releasing or semi-releasing and binding the free-fall brake over a preset period when starting or stopping, a particularly gentle operation can be achieved, which has a positive effect on the service life of the individual components and of the entire earth-moving machine.

[0021] In a particularly preferred embodiment, the input device of the control device comprises a tiltable joystick, and the operator can control the descent speed by the tilt angle of the joystick. In this way, one-handed operation using the joystick can realize particularly simple control of the descent speed, which is very easy for the operator. Furthermore, speed control using the joystick by tilting the joystick facilitates particularly intuitive speed adjustment.

[0022] Another advantageous embodiment of the invention consists in that the input device of the control device, in particular on the joystick, has a control button for starting and stopping the automatic control program. In this way, the winch, in particular with regard to the lowering speed, can initially be controlled manually by the joystick, and the machine operator can switch to automatic operation by simply operating the control button. Further control of the lowering speed and possibly the lowering path can thus be effected via the automatic control program. The control button is preferably arranged directly on the joystick, so that lowering can be effected in an ergonomically rational manner with one hand.

[0023] The free-fall brakes can in principle be constructed in any suitable way. According to one implementation variant of the invention, it is particularly advantageous for at least one free-fall brake to be constructed like a multi-plate clutch with a number of friction disks, also called plates, which can be pressed against one another to brake. The free-fall brake is constructed like a multi-plate clutch in such a way that the contact and friction surfaces increase depending on the number of plates arranged. This allows the transmission of particularly high forces.

[0024] By pressing axially against one another, the plates are connected to one another by force fit or frictional engagement, which allows the transmission of forces between them. In particular, a winch drum connected to a plate on a first side can be connected in a rotationally fixed manner to a winch motor or a holding element connected to the plate on the opposite second side. By appropriately slow axial adjustment of the plates relative to one another, a correspondingly gentle braking effect can be obtained.

[0025] According to a development of the invention, it is provided that the earth-moving machine has a cable grab with a grab shovel, in particular as a diaphragm grab with an approximately rectangular guide frame or as a digging gripper with an approximately cylindrical guide frame, and that there are removal teeth arranged on the grab shovel, which are configured to remove earth.

[0026] The cable grab can be connected via a corresponding cable suspension element on a mast or boom arm to a support device on which the winch is arranged. The support device is preferably mobile and can in particular comprise a crawler chassis.

[0027] According to a further development of the invention, it is advantageous if the cable grab has a first cable for raising and lowering the cable grab and a second cable for opening and closing the grab shovel, and if the two cables are each operable by a cable winch, which is preferably arranged on the support device, thereby allowing a particularly compact construction of the earthmoving machine.

[0028] The method of the present invention for operating a civil engineering machine is characterized in that an civil engineering machine of the present invention is used, at least one free-fall brake is released and locked under the control of an electronic control device and at least one control element, the descent speed and / or the descent path are preset in the control device as setpoint values, the descent speed and / or the descent path of the working unit are detected as actual values ​​by a detection device, and depending on the detected actual values, the release, semi-release and locking of the free-fall brake are controlled by the control device in such a way that the actual values ​​approach the preset setpoint values.

[0029] The method of the invention can in particular be carried out using the above-described civil engineering machine of the invention, so that the advantages described above can be realised, in particular the above-described civil engineering machine can also be operated according to the method of the invention.

[0030] The earth-moving machine can in principle be configured to carry out any earth-moving method. According to a continuous embodiment of the invention, it is particularly preferred that earth is removed by the earth-moving machine. The removal of earth can be carried out in particular in discontinuous operations.

[0031] An implementation variant of the invention consists in that a construction machine with a cable grab is used, by means of which a trench with a rectangular trench cross-section or a hole with a circular hole cross-section is made. By opening and closing the grab shovel, soil from the ground can be taken up into the cable grab when drilling a hole in the ground. The filled cable grab can be extracted from the hole and moved to a discharge point. After being emptied, the cable grab can be returned again to the processing point and lowered into the hole by corresponding operation of the cable winch. In particular, the lowering can be performed according to the method of the invention.

[0032] The invention is explained further below on the basis of preferred exemplary embodiments, which are depicted diagrammatically in the drawings. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a perspective view of a civil engineering machine of the present invention equipped with a cable grab. [Diagram 2] FIG. 2 is a front view of the cable grab of the earthmoving machine of FIG. 1 with the grab shovel closed. [Diagram 3] FIG. 3 is a front view of the cable grab according to FIG. 2 with the grab shovel opened. [Figure 4] FIG. 2 is a schematic cross-sectional view of a winch device equipped with a free fall brake for a civil engineering machine according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] The inventive civil engineering machine 10 according to Fig. 1 may have a mobile support device 12 with a crawler chassis as undercarriage 14. On the undercarriage 14 an upper carriage 16 with a control cabin 17 may be supported rotatably about a vertical axis of rotation. Preferably, inside the control cabin 17, control equipment including input equipment for the machine operator is arranged.

[0035] The boom arm 18 can be articulated pivotally about a horizontal axis on the upper carriage 16. A holding cable 24 can be guided at the tip 20 of the boom arm 18 with a deflection pulley, at the end of which a working unit 30 configured as a cable grab 31 with a grab frame 32 and a lower grab shovel 34 can be attached. The holding cable 24 can be operated via a first cable winch 21 on the support device 12 in order to raise and lower the cable grab 31. Furthermore, a second cable winch 22 can be located on the support device 12 for an operating cable 44, which can likewise be guided via the tip 20 to the cable grab 31 in order to operate the grab shovel 34 at the lower end of the grab frame 32.

[0036] The mode of operation of the earthmoving machine 10 of the present invention is described in more detail below in conjunction with FIGS.

[0037] An operating carriage 42 of an operating device 40 for operating the grab shovel 34 can be supported in a vertically longitudinal direction displaceable in the central region of the grab frame 32. An end of the holding cable 24 can be fixed to an upper end of the operating carriage 42, whereby the cable grab 31 is held via the operating carriage 42.

[0038] A link mechanism 46 with a link rod 47 may be arranged at the lower end of the operating carriage 42. The link rod 47 is preferably articulated at one end to the operating carriage 42 and at the other end to one of the grab shovels 34. The grab shovel 34 may itself be pivotally supported at the lower end of the grab frame 32 by means of a pivot support 35. The grab shovel 34 may be opened and closed by relatively displacing the operating carriage 42 with respect to the grab frame 32. The link rod 47 may be pulled upwards by relatively displacing the operating carriage 42 upwards, whereby the grab shovel 34 is pivoted about its pivot axis 35 to its open position, as is clearly shown in FIG. 3.

[0039] A pulley device 50 for the operating cable 44 may be provided below the operating carriage 42. The pulley device 50 may have an upper pulley 52 rotatably supported on the operating carriage 42 and a lower pulley 54 rotatably supported in a lower region of the grab frame 32. The operating cable 44 fed from above may be wound around the pulleys 52, 54 several times while forming a wrap 56 or tightening, and the lower end of the operating cable 44 is fixedly connected to the grab frame 32. The operating carriage 42 may thus be adjustably connected or coupled to the grab frame 32 by means of the operating cable 44.

[0040] Starting from the open position according to Fig. 3, the operating carriage 42 can be pulled downwards relative to the grab frame 32 by the pulley device 50 by pulling the operating cable 44 upwards by the second cable winch 22. This causes the link rod 47 to press the grab shovels 34 downwards with an increased closing force, which are then pivoted about their pivot supports 35 according to Fig. 2 into the closed position.

[0041] During use in an underground trench, soil can be gripped and clamped between the grab shovels 34 in the process with an increased closing force compared to the pulling force on the operating cables 44 .

[0042] After the cable grab 31 is pulled out of the trench in the ground and moved to the discharge position, the tension on the operating cable 44 can be reduced. In this way, the grab frame 32 can move downwards relative to the operating carriage 42 by its own weight, which causes the grab shovel 34 to rotate back to its open position via the link rod 47, as depicted in FIG.

[0043] The arrangement described here is merely an example: other pulley arrangements having different cable linkages and different link mechanisms could in principle be selected which would facilitate equivalent grab shovel operation.

[0044] When manipulating the cable grab 31, coordination of forces and movements between the holding cable 24 and the operating cable 44 is necessary in order to control the torque of the individual cables and thus of the attached cable grab 31 about its longitudinal axis, in particular due to the so-called lay direction in the case of stranded cables, so that the desired rotation of the cable grab 31 occurs only when required by the installation procedure.

[0045] The forces of the holding cable 24 and the operating cable 44 can be detected by means of suitable detection devices, which can be arranged, for example, on the cable winches 21, 22 or on the deflection pulleys at the tip 20 of the boom arm 18. Via a control device, which is preferably arranged in the control cabin 17 on the support device 12, the winches 21, 22 can be controlled depending on the detected cable forces, so that either a stabilization of the orientation of the cable grab 31 in a swiveling motion about its longitudinal axis or a target twist desired by the machine operator can be realized. On the part of the machine operator, only an appropriate input for an arbitrarily desired compensation mode for the position stabilization or an input for a desired rotational position of the cable grab 31 is required. On this basis, the control device can actuate the cable winches 21, 22 accordingly in order to realize the desired swiveling orientation of the cable grab 31. This considerably simplifies the control of the simple-construction cable grab 31 and makes it easier for the machine operator.

[0046] After emptying the grab shovel 34, the cable grab 31 can be lowered again into the hole in the earth. This can be done in a controlled free fall mode and is explained below in connection with the winch device according to FIG.

[0047] The exemplary winch arrangement according to Figure 4 comprises a cable winch 60 with a winch drum 62 which may be rotatably mounted on a winch frame 64. The winch drum 62 is rotationally driven via a drive shaft 71 by a diagrammatically shown winch motor 70 which may be implemented as a hydraulic motor, and a diagrammatically shown winch gear arrangement 72 which may be a single-stage or multi-stage planetary gear. The cable winch 60 may form at least one or both of the winches 21, 22 of the earthmoving machine 10 described above.

[0048] The free-fall brake 80 according to the invention, which is arranged between the winch motor 70 and the winch drum 62, is constructed like a multi-plate clutch or brake. By operating the free-fall brake 80, it is possible to realize, on the one hand, a rotationally integral coupling between the winch motor 70 and the winch drum 62, in particular between the drive shaft 71 of the winch drum 62, and, on the other hand, a decoupling or semi-decoupling state. In the decoupling state, the winch drum 62 of the cable winch 60 can rotate freely without the existence of a corotating connection with the winch motor 70. By gradually adjusting the plates of the free-fall brake 80, intermediate states between the coupled and decoupling states can also be set, in which a certain slippage can occur between the winch motor 70 and the winch drum 62, which leads to friction between the plate pairs of the free-fall brake 80.

[0049] Holding and locking of the winch drum to the winch frame 64 may be performed by a holding brake 84. A control device 90 is arranged according to the invention for the control, which device may be formed, for example, by a computer or other electronic control unit. The actuation of the winch motor 70, in particular the speed, torque, rotational position, etc., may be performed via the control device 90. Furthermore, the control device 90 may be configured with a first actuator 91 for the release, semi-release and arrestment of the free-fall brake 80. The holding brake 84 may be operated by the control unit 90 via a second actuator 92.

[0050] The machine operator can input into the control device 90 the desired value for the descent speed and / or the descent path of the working unit 30 or the respective corresponding rotation of the winch drum 62. Furthermore, the machine operator can activate the winch motor 70 and the free-fall brake 80 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 descent speed of the working unit 30 attached to the cable winch 60 by tilting a control lever. By means of a control button 98 of the joystick 97 the machine operator can start or stop an automatic program.

[0051] The rotational position and / or rotational speed of the winch drum 62 can be detected via a detection device 94 and sent to the control device 90 as an actual value of the lowering speed and / or lowering path of the attached working unit 30. The corresponding data can be displayed to the machine operator on a monitor, not depicted in FIG.

[0052] When the automatic control program is activated, automatic operation of the free-fall brake 80 by the control device 90 can be carried out in such a way that the actual values ​​detected by the detection device 94 correspond to or at least approach preset target values ​​for the descent speed or, respectively, the descent path.

[0053] In the case of a working unit 30 such as a cable grab 31 having two cables 24, 44, both winches 21, 22 may be operated simultaneously to lower the working unit 30 or respectively the cable grab 31 without opening or respectively closing the grab shovel 34.

Claims

1. A civil engineering machine, in particular a machine equipped with a cable grab (31), a support device (12), a working unit (30) adapted to carry out a civil engineering process and held on said support device (12) by means of at least one cable (24, 44); at least one cable winch (60) for manipulating said cable (24, 44), said cable winch (60) comprising a winch drum (62) and an associated winch motor (70) for driving said winch drum (62) in rotation; and a free-fall brake (80) arranged on the cable winch (60), in which in a locked state of the free-fall brake (80), the winch drum (62) is coupled to the associated winch motor (70), in a semi-released state of the free-fall brake (80), the winch drum (62) and the winch motor (70) are capable of relative movement and a torque corresponding to the degree of release of the free-fall brake (80) is transmitted within the free-fall brake (80), and in a released state, the winch drum (62) is decoupled from the associated winch motor (70) and is substantially free to rotate relative to said winch motor (70); In a civil engineering machine comprising: an electronic control (90) is arranged for effecting said controlled release and arrestment of said free-fall brake (80) by means of at least one actuator (91); the descent speed and / or the descent path can be preset as target values ​​in the control device (90); at least one detection device (94) is arranged and configured to detect the actual speed and / or path of descent of the operational unit (30); the control device (90) is connected to the at least one detection device (94) and is configured to control the release, semi-release and arrestment of the free-fall brake (80) depending on the actual value or the detected actual value, such that the actual value approaches the preset target value; A civil engineering machine characterized by:

2. the at least one winch motor (70) being controlled by the control device (90); the control device (90) is configured to operate the associated winch motor (70) in a downward direction upon release or in particular partial release of the free-fall brake (80) of the cable winch (60), 2. A construction machine according to claim 1.

3. the control device (90) has at least one input device (96) for inputting the descent speed and / or the descent path as target values ​​and / or a control command; 3. A civil engineering machine according to claim 1 or 2.

4. said control device (90) is configured with an automatic control program, which upon input of start and / or stop commands, respectively starts or stops the free-fall operation by gradually releasing / semi-releasing or locking said free-fall brake (80) over a predetermined period of time in response to said commands; 4. A civil engineering machine according to claim 1, wherein the civil engineering machine is a hydraulic excavator.

5. the input device (96) of the control device (90) includes a tiltable joystick (97), and an operator can control the descent speed by the tilt angle of the joystick (97); 5. A civil engineering machine according to claim 3 or 4.

6. the input device (96) of the control device (90) has a control button (98), in particular on a joystick (97), for starting and stopping the automatic control program, 6. A civil engineering machine according to claim 3, wherein the civil engineering machine is a hydraulic excavator.

7. the free-fall brake (80) is configured in the form of a multi-plate clutch having a plurality of friction plates, which can be pressed against each other to brake the free-fall brake; 7. A civil engineering machine according to claim 1, wherein the civil engineering machine is a hydraulic excavator.

8. It has a cable grab (31) with a grab shovel (34), in particular as a diaphragm grab with a substantially rectangular guide frame (32) or as a drilling grab with a substantially cylindrical guide frame, The grab shovel (34) has removal teeth arranged thereon and configured to remove earth. A construction machine according to any one of claims 1 to 7.

9. The cable grab (31) has a first cable (24) for raising and lowering the cable grab (31) and a second cable (44) for opening and closing the grab shovel (34); each of the two cables (24, 44) being operable by a cable winch (60); 9. A construction machine according to claim 8.

10. A plurality of cables (24, 44) are each arranged with a cable winch (60) and can be operated in parallel or synchronously with each other; 10. A civil engineering machine according to claim 1 .

11. A method of operating a construction machine (10), comprising the steps of: a construction machine (10) according to any one of claims 1 to 10 is used, said at least one free-fall brake (80) being released and arrested under the control of at least one control element (92) by an electronic control (90); the descent speed and / or the descent path can be preset as target values ​​in the control device (90); the descent speed and / or the descent path of the working unit (30) are detected as actual values ​​by at least one detection device (94); - depending on the detected actual value, the release and locking of the free-fall brake (80) is controlled by the control device (90) in such a way that the actual value approaches the preset target value; A method comprising:

12. 12. The method of claim 11, wherein soil is removed by the earthmoving machine (10).

13. A construction machine (10) is used that is equipped with a cable grab (31), by which a groove having a rectangular groove cross section or a hole having a circular hole cross section is made.

13. The method according to claim 11 or 12.

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