Patent Application
20230383603
The present invention relates to a foundation construction machine and a method for controlling such machine.
Such type of machine is typically configured for working the soil, generally in order to build structural foundation elements, e.g. piles for a new deep foundation or piles for propping up an existing foundation or the support layer of a shallow foundation, or in order to make retaining elements in the ground, e.g. earth retaining walls or waterproofing bulkheads, or for soil consolidating purposes through the use of appropriate injection and mixing techniques.
Machines employed for building foundations are generally called “foundation construction machines”. They are typically used in a building yard environment and comprise a base machine, a mast or boom supported by the base machine, and an operating equipment carried by the mast. Such machines are typically controlled by means of commands, i.e. control signals, issued by an operator placed in a control station e.g. a cabin or a control board, or by an operator placed at a distance from the machine, e.g. using a radio control unit or a remote control station.
The base machine generally comprises an upper structure and a self-moving or mobile assembly mechanically connected to each other in a fixed or, via a slewing ring, rotatable manner; the self-moving or mobile assembly, which is typically a tracked undercarriage, allows the foundation construction machine to move on the ground and supports it thereon. The upper structure is generally provided with a structural frame housing several components, e.g. a prime mover, typically a Diesel engine, supplying the necessary power to all the devices and the hydraulic and electric systems of the machine. The structural frame also houses one or more control units, typically PLCs, which, together with suitable input/output modules, sensors, limit switches and electromechanical devices, permit controlling the machine.
The mast (also called “boom” when, for example, it is derived from a base machine of a foundation construction crane) is commonly a structural element having a lattice or boxed construction and a long extension, even in excess of forty meters. Said mast is mechanically connected to the frame on the side opposite to the ballast by means of a kinematic mechanism or a pin hinge to make a traverse movement in order to switch from a horizontal position to a substantially vertical position and/or, whenever necessary, in order to change the working radius of the machine. Furthermore, the mast performs the function of mechanically supporting and also—in some types of foundation construction machines—guiding an operating equipment designed to work the soil according to a given processing technology.
The upper structure and/or the mast and/or the kinematic mechanism also house winches adapted to move the operating equipment by means of a rope, typically driven by hydraulic gear motors and braked by overcentre valves and mechanical brakes, and also ballast elements ensuring machine stability during the work. The winches may also have an electrically controlled drive, and therefore may be equipped with an electric motor imparting the rope winding/unwinding motion. The winches may also be driven by a hydraulic unit combined with an electric command.
The foundation construction machines known in the art include the so-called “drilling machines”, wherein the operating equipment comprises, in particular consists of, interchangeable equipment and a drill or consolidation head or a driving head.
The interchangeable equipment may be, merely by way of example, a drilling tool (e.g. a bucket, a drill bit, a core sampler) mechanically connected to telescopic rods called “kelly bars”, a single “continuous flight auger” or “soil displacement” drilling tool, or else it may be ground consolidation equipment (e.g. of the “jet grouting”, “soil mixing”, “deep mixing”, “Turbojet”, “vibro compaction”, “stone column”, “bottom feed system” types). The operating equipment may also be a vibro-drive equipment, e.g. a hammer or a vibrator, constituting a drive head configured to impart ground driving motion to a structural foundation element (e.g. a sheet pile, a pipe, a metal section, etc.).
The drill head, also referred to as “rotary”, is mechanically connected to the mast and can be guidedly made to translate along the mast by means of a rope driven by a winch installed on the upper structure or, as an alternative, by means of a hydraulic cylinder or a rack-type drive system. The drill head is mechanically connected to the interchangeable equipment in order to transfer thereto a rotary motion and a torque of such intensity as to overcome the resistance of the soil and make a hole.
The interchangeable equipment may be mechanically associated with the mast in a direct manner by means of a rope of a winch installed on the upper structure (or on the mast), which supports the interchangeable equipment on the pulleys installed at the top of the mast and moves the interchangeable equipment relative to the mast along the longitudinal direction of the hole. Alternatively, the interchangeable equipment may be mechanically associated with the mast in an indirect manner, being moved by the drill head (in this case, for example, hydraulic cylinders or chain-type gear motor systems or winches equipped with ropes or pinion-rack systems, or the like, are used). The drive head may be associated with the mast either directly or indirectly, and an additional winch installed on the upper structure, called “service winch”, moves an auxiliary rope which, supported by additional pulleys installed at the top of the mast, can be used in order to move foundation elements, such as reinforcement cages, near the hole being made.
Drilling machines also include the so-called “micropile and tunnel machines”, i.e. small to medium size machines employed for making foundations, subfoundations, tie beams, anchors, borings or consolidation works both outdoors (e.g. on a construction site) and indoors (e.g. in buildings, tunnels, etc.).
The foundation construction machines known in the art also include the so-called “diaphragm wall excavation machines”, wherein the operating equipment may be, by way of example, a cutter module, i.e. a frame to which rotary drums equipped with teeth and driven by gear motors are connected in order to make the excavation. Alternatively, in said diaphragm wall excavation machines the operating equipment may be a grab module, i.e. a frame to which mobile clamshells are connected, which are moved by a hydraulic cylinder in order to make the excavation. Furthermore, the operating equipment of a diaphragm wall excavation machine may be a dynamic compaction mass or a drive head. Said operating equipment may be mechanically connected in a direct manner along the mast, in which case they preferably exert a thrust force that facilitates soil penetration, or may be simply suspended by gravity from the mast head by means of a rope in order to work the soil in a substantially vertical direction. In any case, in all known types of foundation construction machines, the operating equipment is mechanically associated with the mast in a direct manner to be moved relative to the mast along the longitudinal direction of the excavation to be made in the soil. From the examples described herein, a person skilled in the art will understand that the definition of foundation construction machine may comprise not only those machine types mentioned above merely by way of non-limiting example, but also other machine types (e.g. also those typically included in the EN16228:2014 product standard series).
In drilling and/or diaphragm wall excavation machines typically equipped with a tracked undercarriage whereon the upper structure is mechanically connected, whether fixedly or rotatably, it is necessary to ensure machine stability in order to prevent the machine from overturning: to this end, as specified, for example, in the EN16228-1:2014 standard, stability verification calculations are made during the designing phase (i.e. calculations verifying that the angle of inclination that will bring the machine into an unstable condition is greater than a value specified in the standards) and soil pressure calculations (i.e. calculations of the value and under-track distribution of the pressure exerted by the machine on the soil) in all possible configurations in terms of loads and machine geometry, and the results of such calculations are reported in the operator manual; in addition, the machine is fitted with limit switches that limit the possibility of movement of parts of the machine to admissible values for stability. When a foundation construction machine turns over in a building yard, this is mainly caused by a reduced bearing capacity of the working platform on which the machine lies, i.e. the layer of compacted and/or reinforced soil that supports the machine, in comparison with the loads transmitted to the platform by the machine. When the platform is not properly compacted and/or reinforced, local subsidence first occurs, and then the machine will start tilting, until the straight line of action of the resultant of all forces acting upon the machine parts (e.g. such forces are the weights of parts and equipment, drilling/excavation forces (while working), centrifugal forces due to rotation of the upper structure, inertia, dynamic actions, wind, etc) exits the perimeter within which the tracked undercarriage rests on the ground, in particular moves past a machine overturning line, so that the overturning motion will become uncontrollable.
If one wanted to modify the foundation construction machine to prevent the pressure generated by it on the ground from exceeding a specific allowable limit value, which value is specific of the working platform whereon the machine lies, and is therefore typically variable depending on the conditions of the soil and/or the type of working platform in use, action could be taken by changing at least one of the three characteristic parameters: the first one is the machine setup, another one is the geometric configuration of the machine, and the last one consists of modifying the type and maximum intensity of the working forces and loads acting upon the machine.
The adopted setup may simply concern any part of the machine that affects the weight thereof and/or the position of its centre of gravity. As a non-limiting example of setup modifications, lighter or heavier machine parts can be selected, such as: the drill head (as aforementioned, also referred to as “rotary”), the “kelly” bars, the mast (which, as previously mentioned, may have a variable length and may be fitted with boxed or lattice extensions), the head at the top of the mast, the mast supporting foot, the working tools (screws, drill bits, casings, etc.) and the ballast (which may either be reduced, in order to lower the weight thereof and reduce the maximum value of the pressure distribution on the ground, or increased, in order to reduce the eccentricity of the centre of gravity and improve the uniformity of the spatial distribution of the pressure under the tracks of the undercarriage, compared with a typically triangular distribution).
The main parameters of the geometric configuration of the machine that mostly affect its stability in operation and the pressure generated on the soil comprise: the working radius of the tool (i.e. the “overhang” of the tool from the base machine, particularly relative to the front and lateral overturning lines defined by the undercarriage and/or by stabilizers or by the mast supporting foot, if present) and the angle of rotation of the upper structure relative to the undercarriage, if the upper structure is a rotary one. Especially in micropile and tunnel machines, further geometric parameters affecting stability and soil pressure include the lateral tilting angle of the mast (i.e. the inclination of the mast about a longitudinal axis of the machine) and, in general, any controllable degree of freedom of the kinematic mechanism connecting the mast to the base machine. In drilling machines, the working radius of the tool is typically changed by actuating, by means of a jack, a kinematic mechanism (e.g. a parallelogram mechanism) that mechanically connects the upper structure to the mast; or in diaphragm wall excavation machines, this is achieved by causing the mast, by means of a winch, to make a traverse movement. The angle of rotation of the upper structure relative to the undercarriage can simply be adjusted by controlling a slewing ring via one or more gear motors. Likewise, the lateral tilting angle of the mast and the degrees of freedom of the kinematic mechanism can preferably be modified by means of hydraulic cylinders and/or a slewing ring and gear motor pair.
The maximum value of the working forces acting upon the machine, i.e. the forces originated during the drilling/excavation process (e.g. the drilling torque of the drill head or the thrust or extraction force acting upon the tool), can be controlled and reduced to decrease the resultant force that is transmitted to the soil by the machine. Merely by way of example, the extraction force of a “continuous flight auger” (CFA) excavation tool is generally exerted according to a ratio of multiplication of the pulling force of a winch (e.g. x2 or x4, thus reaching values even in excess of 100 tons, and in many cases similar to or higher than the weight of the whole foundation construction machine), and therefore has a considerable impact on the intensity of the loads transmitted to the soil by the machine, e.g. via the mast supporting foot. Such forces and loads can be decreased and limited, for example, by means of the machine's control system, by limiting the value of the working pressure of the hydraulic actuators or the value of the current of the electric actuators, or by mechanically modifying the multiplication ratio, as in the above-described case. Other forces acting upon the machine and not directly caused by the soil processing activity, e.g. wind force or the centrifugal force generated during the rotation of the upper structure, are considered as fixed values specified in the product standards.
The stability of the machine and the pressure exerted by it on the soil also depend on the operating condition in which the machine is (e.g. normal operation, transportation, manoeuvers, etc.), since its geometric configuration is different in the various operating conditions. Lastly, also ground slope has an impact on the value and distribution of the pressure generated by the machine on the soil, because such slope affects the relative position of the centre of gravity. In fact, the resultant weight force applied to the general centre of gravity of the machine always remains vertical, while the machine supporting plane takes the inclination of the ground.
In particular, a decisive factor affecting the stability of the foundation construction machine and the pressure generated by it on the soil consists of the overturning moments caused by the various forces acting upon the machine parts (weights of the parts and external loads), i.e. the product of the intensity of the force and the distance of the point of application of such force from a line of possible overturning of the machine: for example, the overturning effect caused by the weight force of the equipment in use is strongly affected by the product of the value of such weight (and also, in working conditions, the resultant of the applied loads) and the value of the current working radius of the machine.
The foundation construction machines known in the art suffer from a few drawbacks.
One of such drawbacks lies in the fact that in prior-art foundation construction machines it is not straightforward to modify the above-described three characteristic parameters so that the maximum value of the pressure generated by the machine on the ground will not exceed a new allowable limit value, e.g. following the use of a working platform having different load-bearing capacity values.
It is therefore one object of the present invention to provide a foundation construction machine which can speed up and simplify the modification of characteristic parameters that affect the value and spatial distribution of the pressure generated by the foundation construction machine on the soil.
It is a further object to provide a method for modifying the characteristic parameters of a foundation construction machine.
According to the present invention, these and other objects are achieved by means of a foundation construction machine and a method having the technical features set out in the appended independent claims.
It is understood that the appended claims are an integral part of the technical teachings provided in the following detailed description of the present invention. In particular, the appended dependent claims define some preferred embodiments of the present invention that include some optional technical features.
The following will summarize some advantages that can be obtained from some favourable aspects and features of the present invention.
One advantage lies in the fact that no machine configuration can be created wherein the value of the pressure exerted on the soil may become critical for the working platform whereon the machine will have to work.
Another advantage lies in the fact that the invention simplifies the selection of that setup modification which will provide the most effective and fastest reduction of the soil pressure values.
A further advantage lies in the fact that the determination of the soil pressure values is verified and certain.
The invention also offers the advantage of making it easier to ascertain which one of the three parameters (machine setup, geometric configuration of the machine, and maximum intensity of the working forces and loads acting upon the machine) will provide the best and optimal reduction of the soil pressure value.
Further features and advantages of the present invention will become apparent in light of the following detailed description, provided herein merely as a non-limiting example and referring, in particular, to the annexed drawings as summarized below.
With reference to
Foundation construction machine 1 comprises a tracked undercarriage 2 configured for moving on the soil, thus moving the rest of said foundation construction machine 1, and configured for withstanding the forces and loads acting upon the rest of foundation construction machine 1 and for transmitting them to soil S whereon the machine lies, i.e. to the working platform.
Foundation construction machine 1 also comprises an upper structure 3 mechanically connected, in a rotatable manner, to tracked undercarriage 2, in particular supported by the latter. Typically, upper structure 3 is mechanically connected, in a rotatable manner, to tracked undercarriage 2 by means of a slewing ring, not shown in the drawing, driven by a gear motor, for rotating upper structure 3 relative to tracked undercarriage 2 about an axis of rotation R of the slewing ring itself.
Furthermore, foundation construction machine 1 comprises a mast or boom 4 mechanically connected to upper structure 3.
Foundation construction machine 1 further comprises a kinematic mechanism 6 that connects mast 4 to upper structure 3. Kinematic mechanism 6 is configured for varying the distance between mast 4 and upper structure 3, in particular for changing the working radius of the machine.
Moreover, foundation construction machine 1 comprises an operating equipment 5 configured to be mounted on mast 4 and adapted to drill the soil.
In the embodiment illustrated in
Foundation construction machine 1 comprises a control station 7, in particular a cabin mechanically connected to upper structure 3. Control station 7 is operationally connected to a control system 8 of the machine, and is configured to be used by an operator, in particular to accommodate an operator, so that, from there, the latter can issue commands aimed at controlling foundation construction machine 1 and display and/or input information about the operation of foundation construction machine 1. In particular, control station 7 comprises control devices 10, such as joysticks and/or control panels and/or pedals and/or levers and/or touchscreen displays and/or push-buttons and/or potentiometers, which are physically operated by the machine operator in order to control the movements of the machine and display and/or input information about the operation of the machine.
In the embodiment illustrated in
As aforementioned, foundation construction machine 1 shown in the exemplary embodiment of
With reference to
In particular, the data archive or database contains at least the maximum values of the pressure distribution generated by the machine on soil S as a function of (i.e. depending on) the above-described three characteristic parameters, i.e. setup, geometric configuration and working forces acting upon the machine.
According to the embodiment illustrated herein, the data archive contains maximum pressure data representative of the maximum values of the pressure generated by the machine on the soil; such maximum pressure data are determined as a function of corresponding: setup data representative of the possible setups of the machine, geometric configuration data representative of the possible geometric configurations of the machine, and working force data representative of the working forces acting upon the machine. In other words, according to one embodiment of the present invention, said data archive or database correlates the maximum values of the pressure generated by the machine on soil S with the characteristic parameters of the machine's setup, the machine's geometric configuration and the working forces acting upon the machine. For brevity's sake, as regards such characteristic parameters reference should be made to the above description of the background art associated with the present invention.
By way of non-limiting example, the geometric configuration data comprise the working radius of operating equipment 5 and/or the angle of rotation of upper structure 3 relative to undercarriage 2. When upper structure 3 is mounted rotatable relative to undercarriage 2 about axis of rotation R, the working radius is defined by the distance between the axis of rotation and operating equipment 5, while the angle of rotation is defined between upper structure 3 and undercarriage 2 in a plane substantially orthogonal to the axis of rotation R.
Still by way of non-limiting example, the setup data comprise, for example, the adopted tool type and/or the length of mast 4 and/or the weight of the installed ballast.
Still by way of non-limiting example, the working force data comprise, for example, the maximum value of the drilling torque and/or the maximum value of the extraction force acting upon the tool.
In particular, such maximum pressure data are preloaded in the database contained in the above-mentioned memory unit 11, i.e. such maximum pressure data are loaded before foundation construction machine 1 is actually used on a construction site by the operator and, preferably, also before it is transported and delivered to the customer.
While using the foundation construction machine on a construction site, the machine operator can easily access the data contained in the database by means of one or more of the above-described control devices 10, preferably a control panel installed in control station 7 (in particular, the cabin), e.g. a touchscreen display, and display them on a display installed in control station 7, possibly the same touchscreen display.
The maximum pressure data preloaded in the database are preferably representative of values measured during a preliminary machine calibration phase, i.e. values obtained by using suitable sensors positioned under the tracks of undercarriage 2, possibly buried in the soil at an appropriate depth underneath the tracks, or by using anchor points suitably arranged in a test area, through which it is possible to simulate operating conditions and exert maximum working forces. For example, measurements of the pressure generated by the machine according to its setup, its geometric configuration and the working forces can be taken during a calibration phase before the machine is put in operation on a construction site, so that it will already have the values preloaded in the database. In particular, such measurements may be taken by the machine manufacturer during the calibration phase by executing a specific test with variable operating parameters.
Optionally, foundation construction machine 1 may automatically preload the measured maximum pressure values into the data archive. In other words, the sensors used for measuring the maximum pressure data may be operatively connected to machine's control system 8 and transfer the measured values to electronic processing system 9 substantially in real time, so that said electronic processing system 9 will store them into its own database during the measurement phase. As an alternative, the measured values may be preloaded manually.
As an alternative or in addition to the above, the maximum pressure data preloaded in the database are representative of calculated values, i.e. values obtained by using suitable formulae instead of sensors, e.g. calculated by means of formulae specified in the reference technical standards, and then manually preloaded into the database.
Advantageously, but not necessarily, the maximum pressure data are calculated according to a plurality of different calculation methods or criteria. In particular, each one of such calculation methods or criteria may use a different formula, e.g. obtained from a respective reference technical standard. Each one of such calculation methods or criteria produces a respective data table and/or map, which is stored into said data archive or database; therefore, in this case, the data archive will contain a plurality of data tables and/or maps obtained by applying the above-mentioned plurality of different calculation methods or criteria. Moreover, when foundation construction machine 1 is in operation, control station 7 can preferably be used by the operator of foundation construction machine 1 for selecting the desired calculation method or criterion. As a result, electronic processing system 9 may be configured for interrogating the data archive and accessing the respective data table and/or map obtained according to the operator-selected calculation method or criterion. For example, the operator may select the desired calculation method or criterion by means of the above-described control devices 10 (in particular, by interacting with a graphic interface, such as a menu, a touchscreen display, or by operating a mechanical push-button and/or selector). Furthermore, the selection of the desired calculation method or criterion may occur under the protection of physical security means, such as a key, and/or computer security means, e.g. authentication by username and password.
It will therefore be appreciated that the maximum pressure data may be preloaded into the database, in particular in accordance with any one of the following options: according to one option, only the maximum pressure data obtained by measurement are preloaded; according to another option, only the maximum pressure data obtained by calculation are preloaded; according to yet another option, the maximum pressure data obtained by measurement and by calculation may both be preloaded, e.g. so that they can be compared.
Optionally, if the pressure generated by the machine on the soil is measured during the calibration phase by using a plurality of sensors arranged under and along each track of undercarriage 2 and/or if it is calculated by using suitable formulae, it is also possible to determine the maximum pressure data and the pressure distribution data and then preload them into the database. Irrespective of the type of preloaded soil pressure values, each one of the maximum pressure data and/or each one of the pressure distribution data is always associated in the database with corresponding data representative of the setup, data representative of the working forces and data representative of the geometric configuration that originated such determined maximum pressure data and/or pressure distribution data.
Merely by way of example, in foundation construction machine 1 of the present invention the operator can manually enter into electronic processing system 9, by selection and/or input via one or more of the above-described control devices 10, actual setup data representative of the setup actually adopted by foundation construction machine 1 (e.g. the weight of the tool and/or ballast in use) and allowable pressure limit values representative of the maximum pressure that can be exerted by the machine on the soil whereon it lies, in particular specific for the working platform in use.
Optionally, it is additionally possible to enter data representative of the minimum pressure that must necessarily be always exerted by the machine on the soil whereon it lies.
As an alternative or in addition to the above, the actual setup data representative of the machine's setup may be automatically inputted to (or entered into) electronic processing system 9 and, in particular, may be detected automatically through the use of one or more sensors installed on machine 1. For example, foundation construction machine 1 may be equipped with a proximity sensor detecting the presence or absence of an auxiliary ballast or a mast extension, or may be equipped with a load cell detecting the weight of the installed operating equipment.
In particular, electronic processing system 9 interrogates the data preloaded in its own database and outputs all the admissible combinations, among the preloaded (i.e. measured and/or calculated) ones, of geometrical configuration data and working force data that correspond to maximum pressure data contained in the data archive (in particular, preloaded therein). In the admissible combinations, the maximum pressure data are smaller than or equal to the allowable pressure limit value data. In other words, the maximum pressure data coincide with, or are lower than, the allowable pressure limit value data specific for the working platform in use, thus ensuring a certain safety coefficient.
Electronic processing system 9 can show said admissible combinations to the operator, whether in numerical and/or graphical form, e.g. by means of a display installed in control station 7, e.g. in the cabin. In particular, electronic processing system 9 can show one or more two-dimensional tables containing the allowable values of the geometric configuration data (e.g. working radius of operating equipment 5 and/or angle of rotation of upper structure 3 relative to undercarriage 2) for certain allowable values of the working forces. Advantageously, the operator can select a predefined and limited number of parameters whose values may vary and, based on such variable values only, determine the corresponding preloaded (i.e. measured and/or calculated) maximum pressures. If the number of such parameters does not exceed three, soil pressures can be shown in graphic form. As an alternative or in addition, such admissible combinations may be shown on the display via one or more three-dimensional graphs, each one representing, by means of a surface, the allowable values of the working radius for different values of the maximum intensity of a given working force and of the angle of rotation of the upper structure. Also, such admissible combinations may be shown on the display via a representation exemplifying a top view of the foundation construction machine, around which the trend of the maximum allowable value of the working radius throughout the 360° degrees of rotation of the upper structure is indicated, e.g. by one or more lines, for different values of the maximum intensity of a given working force. Furthermore, the display may show a two-dimensional graph with the preloaded soil pressure values, possibly compared with the allowable pressure limit value entered by the operator, and a pull-down menu through which the operator can intuitively and quickly select the allowable values of the parameters that affect soil pressure, so as to facilitate and simplify the choice of the best values of such parameters.
Preferably, control system 8 is configured for selecting and outputting said admissible combinations when the latter comply with one or more user-defined constraint conditions. In particular, electronic processing system 9 may adopt a number of selection criteria, e.g. priority and/or optimization criteria, in order to return only a few of said admissible combinations, thus proposing only those admissible combinations which meet particular additional constraints that can be selectively set by the operator. For example, such selection may be done considering also a predefined value of the working force data concerning a particular force (e.g. a predefined value of the maximum force that can be exerted by means of the maximum hydraulic force, or limited to a lower value in order to reduce the pressure on the soil) and/or considering the existence of a sufficient angle of stability and/or that the geometric configuration data are limited to a given range of parameter values (e.g. limited to the front configuration, without turning the upper structure or without tilting the mast laterally) and/or considering only the most conservative values of the admissible combinations, limited to a given range of values of the geometric configuration data. In addition, the operator may select, via the control panel, one or more parameters that must be considered as variable, and may also define a range within which the value of such parameters can change; in this case, electronic processing system 9 will only return those admissible combinations wherein those parameters which have been considered as variable have mutually different values that fall within the operator-defined range, while all other characteristic parameters have, for example, identical values.
Should one or more constraint (or selection) conditions set by the operator not allow the selection of any admissible combinations among those preloaded in the database, electronic processing system 9 will propose some alternative combinations that will still be admissible for the maximum pressure data and/or the angle of stability of the machine although, for example, they minimize the error with respect to said constraint conditions, and will preferably indicate on the display the amount of such error for each one of said constraint conditions.
After viewing the admissible combinations, the operator can select a certain admissible combination, e.g. a certain value of the working radius and a certain value of the maximum intensity of the tool extraction force, and view on the display the trend of the maximum pressure data, preloaded in the database, throughout the 360° of rotation of the upper structure, possibly comparing such maximum value with the allowable pressure limit value data inputted or entered by the operator. Optionally, it is also possible to display the data of the under-track pressure distribution, preloaded in the database, for any angle of rotation of the upper structure. If the operator has selected one or more parameters to be considered as variable, the maximum soil pressure data and/or the pressure distribution data can be displayed for different values of such parameters.
Preferably, both the maximum pressure data and the pressure distribution data shown on the display are preloaded values obtained by measurement; if no measured values are present in the database, electronic processing system 9 will show the preloaded data obtained by calculation. Optionally, the maximum pressure data obtained by measurement and the pressure distribution data obtained by measurement shown on the display are compared with the corresponding values obtained by calculation and, should they differ, such difference will be shown to the operator, possibly signalling it in different ways as its percent value increases.
Electronic processing system 9 may also determine, for any particular combination of the above-described three characteristic parameters, the position of the static and/or dynamic centre of gravity of the machine (i.e. the resultant position of the static centre of gravity only due to the weights of the parts and/or the resultant position of the dynamic centre of gravity due to both the weights of such parts and any other external force acting upon the machine), obtaining it on the basis of the preloaded measured and/or calculated maximum pressure data values, and may show such position on the display both in digital numeric form and in graphic form. Furthermore, electronic processing system 9 may also determine the position of the static and/or dynamic centre of gravity of the machine, for any particular combination of the three characteristic parameters, on the basis of the actual geometric configuration data and the actual setup data. By determining the static and/or dynamic centre of gravity, it is possible to know how close the admissible limit condition is, and then compare the maximum values with the allowable ones and decide if the working condition is sufficiently safe, even before putting the machine in operation.
Optionally, electronic processing system 9 may compare the position of the static and/or dynamic centre of gravity of the machine obtained from the preloaded values of the maximum pressure data with the corresponding position obtained from the actual geometric configuration data and the actual setup data, for the purpose of comparing the two positions thus determined and return a signal to the operator should they differ considerably. Moreover, electronic processing system 9 is also configured for determining the angle of stability of the machine both in static conditions (i.e. the angle of stability of the machine when it is only subject to the weights of its own parts) and in dynamic conditions (i.e. the angle of stability of the machine when it is subject to the weights of its own parts and to external forces) and for showing on the display the value of such angle of stability both in digital numeric form and in graphic form, possibly compared with the minimum value specified in the standards, issuing a signal when the value of the angle of stability approaches such minimum value.
Thanks to the information returned by electronic processing system 9 and shown on the display, the operator can rapidly and intuitively choose the correct geometric configuration and maximum working force intensity for processing the soil by using a given setup of foundation construction machine 1, so that the pressure generated by it on the soil will not exceed a specific allowable limit value.
It should be understood that the case in which the operator enters the actual setup data is only a non-limiting example; as a matter of fact, the operator may, without distinction, enter into electronic processing system 9 data representative of any one of the above-described three characteristic parameters. For example, the operator may enter the maximum working force data or the actual geometric configuration data that the machine should adopt, thereby obtaining, respectively, the allowable setup data to be complied with in order to remain below the specific value of the allowable pressure limit value data with certain geometric configurations. Or, alternatively, the operator will obtain the allowable geometric configuration data to be complied with in order to remain below the specific value of the allowable pressure limit value data with certain maximum working force data. In addition, the operator may also enter into electronic processing system 9 data representative of two of the above-described three characteristic parameters; for example, he may enter the actual setup data and the maximum working force data, and obtain therefrom the allowable geometric configuration data to be complied with in order to remain below the specific value of the allowable pressure limit value data. Alternatively, the operator may enter the maximum working force data and the actual geometric configuration data, and obtain therefrom the allowable setup data that the machine will have to adopt. It should be understood that the data representative of the characteristic parameters may also represent a range of values of such parameters; for example, it is possible to enter a range of values of the angle of rotation of the upper structure, comprised between a maximum value and a minimum value, and electronic processing system 9 will return only those admissible combinations which fall within that range of values.
In a first construction variant of foundation construction machine 1 of the present invention, the admissible combinations outputted by electronic processing system 9—following the entry of the actual setup data and/or the actual geometric configuration data and/or the maximum working force data—are stored into electronic processing system 9, possibly upon confirmation requested to the operator through the display installed in the cabin.
Preferably, foundation construction machine 1 comprises at least one sensor, operationally connected to control system 8 and installed on foundation construction machine 1, which detects, whether directly or indirectly, the actual value of at least one parameter of the geometric configuration of the machine and sends to electronic processing system 9 a signal representative of such actual value; for example, it may be a sensor directly measuring the actual value of the working radius and/or a sensor directly measuring the actual value of the angle of rotation of the upper structure. As an alternative or in addition, said sensor may indirectly detect the actual value of a parameter of the geometric configuration; for example, it may be a proximity sensor configured for detecting when a movement of a part of the machine reaches a given extension, or it may comprise a plurality of proximity sensors configured for detecting the extension of the movement of a part in a plurality of intermediate positions taken by such part during its movement. Such proximity sensors are configured for sending a signal to electronic processing system 9 when the corresponding movement of a part of the machine reaches a given extension, e.g. when the working radius reaches a certain limit extension or when the rotation of the upper structure reaches a certain limit angle. By way of example, the operator inputs or enters the machine's actual setup data and selects the maximum working force data that are representative of the maximum value of the intensity of the working forces; in this manner, while the machine is in operation, electronic processing system 9 will compare the actual values of the geometric configuration of the operating machine with the maximum allowable values of the geometric configuration data referred to the selected maximum value of the working forces, and will have foundation construction machine 1 execute at least one predetermined function when the detected actual values of the geometric configuration are too close (below a predefined threshold value) to the maximum allowable values, so that the actual value can never exceed the maximum allowable values. Such predetermined functions may be one or more functions selected from: emitting at least one audible and/or visual alarm signal, stopping at least one motion of parts of the machine, activating at least one motion of parts of the machine, providing at least one recommendation concerning a necessary change in the setup and/or geometric configuration and/or working forces, in particular aimed at maintaining a given safety coefficient or level as to the allowable pressure limit value and/or the stability of the machine.
Optionally, the operator may also enter or select in electronic processing system 9, via the control panel, maximum limit values for the main parameters of the geometric configuration that the machine may assume in operation, e.g. maximum limit values of the working radius of the tool and of the angle of rotation of upper structure 3. Such maximum limit values of the working radius and of the angle of rotation of upper structure 3, are those values of foundation construction machine 1 which the operator does not intend to exceed in operation. In particular, entering such maximum limit values creates a range of values that can be used in operation; for example, if the operator enters a maximum limit value of 3 meters for the working radius, this means that foundation construction machine 1 may assume, in operation, any working radius value between the minimum physically possible value and the maximum limit value of 3 meters entered by the operator. Advantageously, the limit values that can be set by the operator are selectable among those values which can be detected, whether directly or indirectly, by control system 8 of the machine by means of the sensors. As an alternative or in addition, also minimum limit values of the main parameters of the geometric configuration of the machine, i.e. values below which the operator does not want to go in operation, can be entered or selected by the operator. If the operator enters both a maximum limit value and a minimum limit value for one parameter of the geometric configuration, that parameter may assume, in operation, any value between such limit values entered by the operator. If the two limit values coincide, then such geometric configuration parameter will be a fixed value and control system 8 will vary the other parameters only. In this case, the admissible geometric configurations returned by electronic processing system 9 will be simultaneously limited by the limit values of the geometric configuration entered by the operator and by the allowable pressure limit value.
In a second construction variant, foundation construction machine 1 also comprises, in addition to what has been described herein with reference to the first variant, at least one sensor, operationally connected to control system 8 and installed on foundation construction machine 1, which detects, whether directly or indirectly, the actual value of at least one working force acting upon the machine, e.g. a load cell mounted at the top of mast 4. The operator only enters the machine's actual setup data; in this manner, when the machine is in operation, electronic processing system 9 will compare the actual values of the geometric configuration assumed by the machine in operation with the maximum allowable values of the geometric configuration referred to the actual value of the working forces, and will compare the actual value of the at least one working force with the maximum allowable value of such force referred to the actual values of the geometric configuration. Electronic processing system 9 will have foundation construction machine 1 execute at least one of the previously described predetermined functions when the actual values of the geometric configuration and/or the actual value of at least one working force turn out to be too close (below a predefined threshold value) to the respective maximum allowable values, so that the actual values of the geometric configuration and/or the actual values of the working forces can never exceed the respective maximum allowable values. In general, it will be appreciated that the second construction variant of foundation construction machine 1 of the present invention always comprises at least one sensor reading the actual value of at least one working force, while it may not comprise a sensor reading the actual value of at least one parameter of the geometric configuration of the machine.
In particular, control system 8 may be set with the maximum allowable force values obtained from an admissible combination, so that the intensity of the force will never exceed such maximum values; for example, machines equipped with electro-proportional systems have settings that can be automatically entered by control system 8, or on electro-hydraulic machines suggestions may be shown on a display concerning the settings that need to be made (e.g. adjustment of a pressure relief valve of the hydraulic system). In this latter case, it will be advantageous to monitor in real time the value of the actual hydraulic pressure of the drive outputting the force that needs to be limited, so as to constantly verify that the set value is not exceeded, in which case an alarm signal will be sent to the operator. As an alternative or in addition, it is possible to determine the actual value of at least one working force on the basis of the value of the actual hydraulic pressure, for the purpose of comparing the actual value thus determined with the actual value detected, whether directly or indirectly, by the at least one sensor, and sending an alarm signal to the operator when the difference between such actual values exceeds a predefined threshold value.
Optionally, it is also possible to use sensors that measure the tensional state at specific points of undercarriage 2, so as to detect the actual resultant loads acting upon the machine, e.g. strain gauges arranged in proximity to the slewing ring that connects undercarriage 2 to upper structure 3, or load cells arranged in proximity to pins that connect the tracks to undercarriage frame 2. In this case, control system 8 can make a comparison between the actual resultant loads acting upon the machine and measured by the sensors arranged in proximity to undercarriage 2 and the resultant loads that should be acting upon the machine as calculated on the basis of the actual setup data entered by the operator and of the measured actual values of the working forces. If the comparison shows negligible differences, this means that the actual setup data manually entered by the operator via the control panel correspond to the real setup adopted by the machine. If the differences are substantial, i.e. greater than a predefined threshold value, this means that the actual setup data entered by the operator differ from those of the setup actually adopted, and the control system will issue a signal to warn the operator that some selected options and/or some input data are incorrect, requiring him to verify them again. Should the operator confirm the correctness of the entered data, control system 8 will issue a further signal to warn the operator that the proper operation of the sensors should be checked because the comparison has shown substantial differences.
With particular reference to
Said method further comprises the following steps:
Preferably, the method further comprises the step of entering into control system 8, by an operator and by means of said control station 7, actual setup data representative of the setup adopted by the foundation construction machine, and maximum allowable pressure limit value data representative of the maximum pressure that can be exerted on the soil whereon the machine lies. The interrogation is carried out as a function of the actual setup data and the maximum allowable pressure limit value data.
Even more preferably, the method further comprises the step of outputting, through control system 8, at least one admissible combination of the geometrical configuration data and/or working force data. Such at least one admissible combination is correlated with corresponding preloaded maximum pressure data contained in the data archive, which are smaller than or equal to the entered allowable pressure limit value data.
Other functional and structural details of the method have already been described above with reference to embodiments and construction variants of foundation construction machine 1 and will not therefore be repeated for brevity's sake, but should be understood to be applicable to the present method without requiring any further description or explanation.
Of course, without prejudice to the principle of the invention, the various embodiments, construction variants and implementation details may be extensively varied from those described and illustrated above by way of non-limiting example, without however departing from the scope of the invention as set out in the appended claims.
In particular, although the figures have been described with reference to the working radius and the angle of rotation of the upper structure, it is likewise possible to take into account any other parameter of the geometric configuration of the machine that affects its stability in operation and the value of the pressure exerted on the soil (e.g. one may consider any mast tilting angle and/or any degree of freedom of the kinematic mechanism of the machine). In fact, the mast may be tilted laterally, forward and/or backward to execute the necessary drilling operations, and such angles of inclination may be either fixed or variable according to specific conditions (e.g. when it is necessary to switch from vertical drilling to a next translation with the mast tilted backward to improve the stability of the machine). In such cases, variations in these parameters may also be taken into account when determining the pressures exerted on the soil.
Likewise, those machines which are equipped with a fixed, as opposed to rotary, upper structure may have a mast that can be traversed laterally; therefore, depending on the positions taken by the latter, it is possible to determine the trend of the maximum pressure exerted on the soil. Or, as is typically the case in tunnel machines, the mast may be moved by rotary arms describing circles at the front, with the mast in a sub-horizontal condition. By rotating the mast from a configuration centred in the longitudinal plane of the machine to a configuration in a lateral plane, the load applied to one of the two tracks will gradually increase while the load on the other track will decrease, and therefore also in this case the condition of maximum pressure on the soil can be determined as a function of the variations occurring in this parameter.
Furthermore, the machines may have a control station 7 consisting of a cabin fixed to upper structure 3, or they may have a remote control station 7 (drilling and/or positioning and/or translation control board) that an operator can use from the ground to control the machine while remaining in a more visible and safer condition, depending on the commands to be issued.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102020000025255 | Oct 2020 | IT | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/059809 | 10/25/2021 | WO |
