Patent Application
20250092739
The present invention relates to a method according to the preamble of claim 1 as well as to a working machine comprising a controller for carrying out the method, and to a corresponding computer program product.
Working machines of this kind typically comprise a carrier device comprising a chassis, which optionally receives a rotatably mounted superstructure. The superstructure in turn provides a leader for receiving the required tool, for example a pile-driving tool for driving in or vibrating in pile elements or a drilling tool for Kelly drilling. The inclination of the leader can usually be varied by support cylinders or inclination cylinders. In a rotary drilling rig for Kelly drilling, the drilling tool is actuated by a rope hoist and a telescopic Kelly rod. The leader can comprise a crowd system comprising a sledge that is adjustable along the leader, wherein the crowd force is usually generated by means of a hydraulic crowd cylinder or a crowd rope.
Depending on the working method, the operating parameters and the state of the working machine, critical situations can occur during the work operation. For instance, in drilling rigs Kelly extensions are often used in order to increase the drilling depths or mixing depths that can be reached during continuous drilling and mixing work. At certain/critical speeds, there is the risk that there might be a build-up or upswing in oscillations of the tool, and this can cause damage to the tool and the machine. The upswing behaviour of the drilling tool is, however, difficult to predict, since it depends on many factors such as the free length, the rigidity, the straightness and the imbalance of the tool, the support of the leader (leader support foot) and the interaction with the ground. Play in connection elements of the tool or leader also influences the upswing behaviour.
Until now, in a build-up of oscillations, it has typically come down to the subjective feeling or experience of the operator of the working machine. Furthermore, for safety reasons, the operating range or the scope of application of the working machine is often limited, for example by limiting a maximum speed of the drilling tool and by making it necessary to actuate a release switch in order to enable higher speeds. During the drilling, it is routine, for example, not to enable the use of a Kelly extension for certain fields of application involving high speeds, e.g. for soil mixing.
The object of the present invention is to increase the safety of working machines of this kind during the work operation and in particular to enlarge its safe usage range.
According to the invention, this object is achieved by a method having the features of claim 1, by a working machine having the features of claim 14, and by a computer program product having the features of claim 15. Advantageous embodiments of the invention are found in the dependent claims and the following description.
Accordingly, a method for monitoring the work operation of a working machine is proposed. The working machine comprises a controller, a detection apparatus, a carrier device and a leader fastened to the carrier device, on which a tool, in particular a pile-driving or drilling tool, is mounted. In a work operation of the working machine, at least one force currently acting on a connecting point and/or a piston-cylinder unit of the working machine is detected by means of the detection apparatus and is transmitted to the controller.
According to the invention, an oscillation amplitude of the force measured by the detection apparatus is determined by the controller. This takes places in particular by means of an amplitude recognition algorithm, which can be known per se from the prior art. The oscillation amplitude determined from the measured data and/or a value derived therefrom is then compared with at least one limit value by the controller. If a limit value is reached (if the amplitude falls below or exceeds it), the controller automatically performs a measure.
The determined oscillation amplitude is in particular not an absolute force value, but a relative value, which represents the maximum deviation (or the magnitude of the deviation) of the detected force of an average force value or the difference between a maximum force value and a minimum force value (so-called peak-to-peak amplitude), for example in a certain interval (e.g. an oscillation cycle).
The at least one limit value can in principle be a limit value that is calculated dynamically by the controller during the work operation. In the simplest case, however, the at least one limit value can be stored in the controller or in a data memory connected to the controller, for example.
A core concept of the present invention is to recognise operation-critical states in good time and in a reliable manner by analysing the oscillation behaviour of a piston-cylinder unit and/or connecting point of the working machine and to automatically take suitable countermeasures. This analysis is based on a force measurement at the piston-cylinder unit and/or a connecting point of the working machine. Here, absolute force values, such as an average or mean value, are in particular not used for the analysis, but instead changes over time of the detected force are used.
The term “oscillation amplitude” is not limited to particular oscillations, such as a purely sinusoidal oscillation, but instead covers fluctuating or oscillating force progressions that generally vary over time. The oscillations can be periodic or non-periodic or can be a combination of periodically oscillating and non-periodically oscillating sections or portions. Force oscillations of this kind can occur in particular in rotating components of the working machine, such as a drilling tool or drill rod, and can have a frequency that depends on the speed of the rotationally driven component. However, during other work processes such as shaking in or driving in pile elements, oscillations can also occur in the detected force, which can be used and analysed for the monitoring.
By analysing the change over time in the detected force or by determining the oscillation amplitude and monitoring against corresponding limit values, the controller can automatically recognise critical operating states, such as a build-up or upswing in the oscillations of a drilling tool in certain speed ranges, and automatically take countermeasures (e.g. warn the operator and/or intervene in the control of the machine). As a result, safe operation is no longer dependent on critical states of this kind being recognised in good time by the machine operator. At the same time, this means that the usage range of the working machine can be expanded, since safe operation can be provided even in operating ranges that were previously inaccessible or were only accessible after being accordingly enabled. As long as the oscillation amplitude or a variable derived therefrom remains within the respective limits, a work operation can take place.
In principle, the analysis of the oscillation amplitude of the detected force can be combined with the detection and analysis of any other variables and operating states. Here, other operating principles, such as the detection of accelerations (e.g. by means of one or more vibration sensors), can also be used.
In the present case, the term “pile-driving tool” is intended to cover both vibration tools and conventional pile-driving devices, such as hydraulic hammers. The carrier device can comprise a chassis, for example a wheel-mounted chassis or a track-mounted chassis. The leader can be fastened to a superstructure mounted on the carrier device (undercarriage) to rotate about a vertical axis of rotation.
The leader is preferably articulated to the carrier device and/or an adjustment mechanism connecting the leader to the carrier device (also referred to as the leader kinematics) so as to be pivotable about a horizontal pivot axis. Said connecting point is in particular an articulated connection between the leader and the carrier device and/or the adjustment mechanism. In principle, however, this can be any connecting point of two components of the working machine.
The adjustment mechanism can comprise one or more inclination cylinders for orienting the leader and/or parallelogram kinematics for moving the leader between a transport position and a raised working position and/or a swingarm, to which the leader is articulated. The parallelogram kinematics can comprise one or more main arm cylinders.
The leader can comprise a leader guide, on which a sledge that is adjustable along the longitudinal axis of the leader is mounted, wherein the sledge can carry a component such as a drill drive, an exciter block for generating vibrations, or a hydraulic hammer. The sledge can be actively adjustable by means of a crowd system comprising a crowd rope and/or a crowd cylinder.
The controller can be or comprise a central control unit of the working machine, a separate control unit or a plurality of such control units.
The detection apparatus preferably comprises one or more sensors, which are arranged on one or more components of the working machine. The analysed force can be detected indirectly, e.g. by measuring a pressure in a hydraulic cylinder.
In one possible embodiment, it is provided that a force currently acting on an inclination cylinder for orienting or inclining the leader relative to the vertical and/or acting on a main arm cylinder of parallelogram kinematics for moving the leader between a transport position and a raised working position is detected and is provided to the controller for monitoring the work operation. These hydraulic cylinders are arranged between the leader and the carrier device, such that oscillations of the leader or the tool act thereon. The oscillation behaviour of the leader or the tool fastened thereto can therefore be monitored by detecting the forces (which can in particular be derived from the pressures prevailing in the cylinders).
Alternatively or additionally, a force currently acting on a leader support foot or any other force acting on the leader can be detected and can be provided to the controller for the monitoring.
In another possible embodiment, it is provided that the controller determines a change in the oscillation amplitude and/or a variable derived therefrom over time and compares it with at least one limit value. For instance, a significant and/or rapid change in the oscillation amplitude can indicate a speed range of a tool or drill drive which results in upswing behaviour.
In another possible embodiment, it is provided that the measure automatically taken by the controller comprises an output of an optical and/or acoustic signal, in particular a warning signal, to an operator. For instance, a warning can be displayed on a display unit in a driver's cab of the working machine and/or on a mobile terminal device. The signal can be transmitted in a wired or wireless manner.
Alternatively or additionally, the measure automatically taken by the controller can comprise an output of a control signal or an automatic intervention in a current work operation of the working machine. The controller can in particular slow down (e.g. speed reduction), stop or reverse a machine movement influencing the oscillation amplitude, for example a speed of a drill rod or drill drive. For this purpose, the controller is in particular connected to corresponding actuators of the working machine, which control the movement of various components of the working machine, such as the drill drive, leader kinematics, superstructure, Kelly rope and/or crowd system.
The controller can thus be or comprise a corresponding assistance system for the operator, which automatically warns the operator of critical operating states and/or automatically intervenes in the machine control.
In another possible embodiment, it is provided that the oscillation amplitude is a peak-to-peak amplitude of the detected force.
In the oscillation analysis for the monitoring according to the invention, an averaged value (e.g. a mean, median, long-term maximum, long-term minimum, etc.) of the detected force is preferably not taken into account. Alternatively or additionally, an oscillation frequency is preferably not taken into account in the oscillation analysis for the monitoring according to the invention. In the simplest case, merely the oscillation amplitude is therefore determined and analysed, which is possible in a rapid, simple and reliable manner by means of corresponding algorithms. The detected force can of course be used for additional analyses/monitoring operations, wherein averaged values and/or oscillation frequencies can also be analysed for this purpose.
In another possible embodiment, it is provided that the detection apparatus additionally detects one or more of the variables set out in the following and provides it to the controller for monitoring the work operation and comparing with at least one corresponding limit value.
By means of the detection apparatus, the controller can obtain a current position of a piston-cylinder unit, in particular an inclination cylinder and/or main arm cylinder and/or crowd cylinder and/or leader support cylinder or leader support foot. This may be an extended position of a piston rod of the cylinder.
Alternatively or additionally, the controller can obtain a current speed and/or a current acceleration of a component of the working machine by means of the detection apparatus, for example a current rotational speed of a drill drive and/or a drill rod or drilling tool.
Alternatively or additionally, the controller can obtain a current cylinder pressure of a piston-cylinder unit of the working machine by means of the detection apparatus, in particular a hydraulic pressure in an inclination cylinder and/or main arm cylinder and/or crowd cylinder and/or leader support cylinder. The corresponding force can be calculated from the detected pressure, wherein a change in a pressure oscillation is translated into a change in the corresponding force.
Alternatively or additionally, the controller can obtain a current position of a component of the working machine by means of the detection apparatus, in particular a current position of the leader (e.g. detecting the projection and/or inclination of the leader) and/or a sledge mounted on the leader and/or a drilling tool and/or a superstructure (e.g. detecting the superstructure rotary angle) and/or a leader top arranged on the tip of the leader and/or a sub-component of parallelogram kinematics, such as a main arm and/or a swingarm connected to the leader.
Alternatively or additionally, the controller can obtain a current drilling depth by means of the detection apparatus.
In another possible embodiment, it is provided that a current drilling depth is detected by means of the detection unit and is set in relation to the determined oscillation amplitude, wherein, from said relation, the controller determines a soil condition and/or compiles a soil model, in particular in the form of a soil depth profile. As a result, the measured values used for the monitoring according to the invention can simultaneously be used for assessing the soil conditions or for compiling a soil depth profile. Additional data and/or measured values can be used for this purpose.
In another possible embodiment, it is provided that a current state of at least one component of the working machine is concluded from the determined oscillation amplitude. This includes the state of connections to other components of the working machine. For instance, it has an influence on the oscillation amplitude when a connection between a sledge mounted on the leader and the leader itself, or between the leader and the carrier device or an adjustment mechanism, has play caused by wear. The analysis of the oscillation amplitude of the detected force therefore allows for statements regarding the current state of the working machine. The determined oscillation amplitude or a progression over time of the oscillation amplitude is preferably compared with an earlier measured value or detected progression for this purpose, in order to conclude a current state of the working machine in particular by means of a recognised deviation.
In another possible embodiment, it is provided that the at least one limit value for the oscillation amplitude and/or for a value derived therefrom is based on earlier measured data for the same working machine. The at least one limit value can be determined by measurements on a test bench, for example. It is likewise conceivable for the measured data for the detected force to be archived in a data memory and for a corresponding limit value for the tool used and/or the working mode under consideration to be determined from these data, which value is taken as the basis for the monitoring of the ongoing work operation. Alternatively or additionally, measured data for a plurality of working machines in a fleet can be evaluated. They preferably store their detected measured values on corresponding data memories, such that they can be evaluated later.
Alternatively, however, it is of course conceivable for the at least one limit value not to be determined from earlier measured data, but to be specified in another way, for example by a simulation and/or a calculation.
In another possible embodiment, it is provided that the controller determines a difference or a ratio of the detected oscillation amplitude to a specified reference value and/or to an earlier measured value of the oscillation amplitude, compares the difference or ratio with at least one limit value, and, if a limit value is reached, automatically performs a measure. As a result, the controller can react to a sudden change in the oscillation amplitude. If this change is greater than a specified reference value and/or the change is to a certain earlier measured value (for example the previously detected value), a measure is automatically taken. The difference or ratio can relate to a change to higher or lower oscillation amplitudes.
In another possible embodiment, it is provided that the controller calculates a prediction for a future state of at least one component of the working machine from the determined oscillation amplitude and/or a value derived therefrom and preferably from earlier measured values of the detected force. The prediction can be taken as the basis for a progression over time of the detected oscillation amplitude or a value derived therefrom. Furthermore, a model of the working machine and/or a current machine configuration and/or at least one further state value can be taken into account. As a result, it is for example possible to predict a defined wear limit of one or more components of the working machine (e.g. a drilling tool or a drill rod) or a time for future maintenance work (“predictive maintenance”) being reached.
In another possible embodiment, it is provided that the controller takes into account a current machine configuration for monitoring the work operation. This can be stored in the controller and/or can be automatically recognised by sensors of the detection apparatus. Alternatively or additionally, the working machine can comprise an input unit, by means of which an operator can input a current machine configuration (e.g. the tool type used) and optionally other settings or machine parameters.
The invention further relates to a working machine comprising a carrier device, a leader fastened to the carrier device, a detection apparatus and a controller, wherein the controller is configured to carry out the method according to the invention. The working machine is preferably a civil engineering machine, in particular a rotary drilling rig or a vibrating pile driver, wherein, in principle, any working machine comprising a leader comes into consideration. A working machine comprising a leader to which a trench wall cutter is fastened is also conceivable. This clearly results in the same properties and advantages as for the method according to the invention, which is why they are not described again.
The invention further relates to a computer program product comprising commands which, when the program is executed on the controller of the working machine according to the invention, cause the steps of the method according to the invention to be performed. This also clearly results in the same properties and advantages as for the method according to the invention, which is why they are not described again.
Further features, details and advantages of the invention are found in the following exemplary embodiments, which are explained with reference to the drawings, in which:
The working machine 10 in this exemplary embodiment comprises a carrier device 11, which in turn comprises an undercarriage 12 comprising a track-mounted chassis and a superstructure 13 mounted on the undercarriage 12 to rotate about a vertical axis of rotation. A leader 14, which is adjustable relative to the superstructure 13 by means of an adjustment mechanism 20, is mounted on the superstructure 13. As shown in
The leader 14 can be adjusted relative to the vertical by means of one or more hydraulic inclination cylinders 22 (also referred to as support cylinders). In the following, two inclination cylinders 22 are taken as a starting point. They are connected to the swingarm and the leader 14 and pivot the leader 14 by accordingly extending or retracting the piston rod in question. However, alternative adjustment mechanisms comprising inclination cylinder(s) are also conceivable. For instance, one or more inclination cylinders could directly connect the leader 14 to the carrier device 11 or superstructure 13 or to a frame anchored in the ground. In all of these configurations, the method according to the invention can be carried out by a force measurement at the at least one inclination cylinder.
In the exemplary embodiment shown in
The Kelly rod 17 is actuated in particular by a Kelly rope (only shown in part), which is guided from the Kelly rod 17, over a leader top 15 positioned at the upper end or head of the leader 14, to a Kelly winch, which can likewise be arranged on the leader 14. The drill 16 can be sunk into the earth via the Kelly rope and the Kelly rod 17 in line with the drilling progress.
At certain/critical speeds of the drill drive 19 or the Kelly rod 17, there is the risk that there might be an upswing in oscillations of the tool 16, and damage can be caused to the tool 16 and the working machine 10. In this case, the upswing behaviour of the tool 16 is difficult to predict, since it depends on many factors, for example the free length of the tool 16, the rigidity of the tool 16, the straightness of the tool 16, possible soiling of the tool 16, a possible imbalance of the tool 16 about the axis of rotation, the interaction with the ground, play that is potentially present in connection elements between the tool 16, the drill rod 17, the leader 14, the sledge 18, the adjustment mechanism 20 and/or the superstructure 13, etc.
The working machine 10 comprises a controller 30, which is indicated schematically in
The working machine 10 further comprises a detection apparatus 32, which comprises at least one sensor, preferably a plurality of sensors, which are connected to the controller 30 and provide measured data thereto. One of the sensors of the detection apparatus 32 detects a current force which is acting on a piston-cylinder unit and/or at least one connecting point of the working machine 10 and provides it to the controller 30 for evaluation. Critical operating states of the working machine 10 are monitored on the basis of the detected force, as explained in the following on the basis of an exemplary embodiment in which the detection apparatus 32 detects the force acting on one or both inclination cylinders 22 and transmits it to the controller 30.
One example of the above-described upswing behaviour of the tool 16 is shown in
In the graph in
The absolute values of the detected force are in particular non-critical per se. The build-up of the oscillations constitutes the critical operating state. It is also clear that this critical state is not reflected in an averaged force value, a maximum value of the detected force or an oscillation frequency or exciter frequency, but in a change in the oscillation amplitude.
The controller 30 of the working machine 10 according to the invention determines the oscillation amplitude (in particular peak to peak) from the detected force and compares it with at least one limit value in order to recognise critical operating states in good time and react to them.
For instance, the operator of the working machine 10 can be warned when an amplitude limit value is exceeded. The amplitude limit values can be determined by means of measured data for the working machine or by means of measured values for a complete fleet of working machines of this kind, and by evaluating this measured data. In addition to the warning given to the operator or driver, it is also conceivable to implement an assistance system, which automatically reacts to the measured oscillation amplitudes and initiates countermeasures. In the case described, this could be a reduction the drill drive speed, for example, in order to return to a non-critical range again.
In addition to the force measurement at the at least one inclination cylinder 22, further measurement sensors can be installed on the working machine 10, for example at least one acceleration sensor on the drill drive 19, at least one optical position sensor on the inclination cylinder 22, at least one pressure sensor in a main arm cylinder, at least one inclination transducer on a main arm, at least one inclination transducer on a swingarm and/or at least one inclination transducer on the leader top 15.
In addition to the application described, further options for analysing and monitoring the detected force are conceivable:
For instance, the soil conditions over the drilling depth could be assessed, i.e. a soil profile could be determined, by recording the oscillation amplitude as a function of a detected current drilling depth.
Alternatively or additionally, by means of the oscillation behaviour of the force on or in the inclination cylinder 22, conclusions can be drawn on a current state of the working machine 10 or at least one component of the working machine 10. It would be conceivable here that all the mechanical connections having play can be assessed. If, for example, guide elements of a sledge 18 for guiding and mounting the sledge 18 on the leader 14 are worn or if a pin fitting on the adjustment mechanism has been worn down, this can be measured from the oscillation amplitudes of the inclination cylinder(s) 22. Proceeding from the current state of the working machine 10 detected thereby, it is also possible to make statements regarding future maintenance work (predictive maintenance). For this purpose, the detected oscillation amplitudes or a progression of the oscillation amplitudes over a particular period of time could be compared with earlier data for other working machines (or the same working machine 10 before earlier maintenance work). For example, it can be deduced from the earlier data that a replacement needs to be made or maintenance needs to be carried out within a predetermined time when a certain oscillation amplitude is reached at a certain speed.
During drilling, it is not uncommon for the drilling tool 16 to suddenly catch in the ground, for example if the drilling tool 16 strikes a boulder. These sudden loads present considerable challenges for the mechanical construction and for example for a hydraulic drive unit on the drill drive 19. If such events only occur occasionally, the working machine 10 is generally designed for this. In this case, the static loads of the design are not exceeded. If these events are repeated frequently, however, damage may be caused to the working machine 10. By measuring and analysing the cylinder force in the inclination cylinder 22, the main arm cylinder and/or in a leader support, the number, extent and frequency of these events can be detected. Here, the operator of the working machine 10 and/or a provider can in turn be warned. In addition, these data can be used for designing the carrier devices in future.
In other applications in deep foundation engineering, too, operating errors can be detected by detecting the load in the inclination cylinder 22. This is intended to be explained in greater detail on the basis of an example in the case of a vibrating pile driver: two sheet piles are driven in by means of the interlock using the single clamp. When positioning a double sheet pile, one of the two sheet piles slips by a few cm. The driver cannot see this, since the sheet pile is not within their field of vision. The sheet pile that has slipped can then only be minimally clamped by the tip of the clamp. Despite the poor clamping, the driver attempts to shake in the sheet piles. This asymmetrical load from the clamp can result in damage to the clamp and the sheet pile. In addition, the driver might not be able to fully insert the sheet pile and would have to install it again, which is time-consuming. This problem of suboptimal clamping can be recognised by analysing the detected force, in particular the oscillation amplitude, since the force signal differs when compared with previous, correctly clamped sheet piles. As a result, the driver can be automatically warned and/or the shaking process can be interrupted, such that the sheet pile that has slipped can be correctly gripped. This prevents damage and saves time for notifying the driver.
Another possible application is a comparison of the force acting in the inclination cylinder 22 and/or at another connecting point with a dynamically calculated limit value for the force. The force limit value can, for example, be determined on the basis of a currently permissible limit value for a maximum structural load of a component of the working machine (e.g. drill drive 19 and/or drilling tool 16 and/or drill rod 17). This currently permissible structural-load limit value can in turn be calculated from the current device configuration and at least one state value (e.g. a detected rope pull force and/or a detected leader position). This would result in effective and ongoing monitoring of the structural load of individual structural elements of the working machine by each loaded component not being individually monitored for a structural overload, but instead, in place of this, an appropriate measured variable (namely a force that is acting, e.g. in the inclination cylinder 22) being used for monitoring the structural load of one or more specific machine components, on the basis of physical relationships.
The method according to the invention can alternatively or additionally be based on a detected force which acts on any connecting point of the working machine.
The method according to the invention can be applied to any working machine comprising a leader and therefore has a wide field of application.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 125 273.9 | Sep 2023 | DE | national |
