Method of Operating a Working Machine

Description

[0001] This invention relates to a method of operating working machine of the kind which is drivable on the ground and which has a working arm carrying at an outermost end, a working implement such as a loading forks or loading bucket for examples.

[0002] Particularly such machines which are used for loading and unloading, are prone to longitudinal instability when handling loads at height, and/or at distance from a main structure of the machine. Accordingly it is a statutory requirement at least in Europe, for such machines to be provided with a longitudinal load moment control system which automatically prevents operation of the working arm at least in a manner which could increase the longitudinal instability of the machine beyond a safe limit. It is also a requirement for such machines to have a longitudinal moment indicator to provide a warning to an operator of an impending longitudinal unstable condition.

[0003] A longitudinal load movement control system is an essential safety feature particularly where such a machine is used in public places or places where there are workers, such as on the highway or on construction sites. It is also a requirement for such machines which are used for loading and unloading operations that such operations are carried out while the machine is stationary, and that when the machine is travelling on the ground, the working arm when the implement is loaded, is substantially lowered. According to the legistation, the longitudinal load moment control system may be disabled when the working arm is fully retracted.

[0004] Where such machines are used in an agricultural context, commonly the surface on which the machine has to travel when being driven from one location to another location, is particularly uneven.

[0005] Known longitudinal load moment control systems are provided on all working machines regardless of their intended use. It will be appreciated that when a machine provided with such a longitudinal load moment control system is used in an agricultural context i.e. the machine is driven on particularly uneven ground, a longitudinal load sensor of the control system may be subject to transient forces which indicate longitudinal instability, and so the longitudinal load control system may operate automatically to prevent or stop operation of the working arm when this is not required. This false indication can actually lead to an increase in the machine's instability.

[0006] GB2390595 discloses a load handling apparatus of a machine of the type having a lifting arm which is moved about a horizontal axis by a first actuator, has a sensor that acts to sense tilting moment and acts to progressively reduce the speed of the load as it approaches a threshold value.

[0007] According to a first aspect of the invention we provide a method of operating a working machine which includes a main structure, and a working arm, the working arm being pivotally, mounted on the main structure at one end of the arm, the working arm being raisable and lowerable relative to the main structure by a first actuator device, and being extendible relative to the main structure by a second actuator device, and the arm carrying in use at its other end a corking implement which in use carries a load, the machine further including a ground engaging drive structure by which the machine is driveable on the ground, and the machine having a longitudinal load moment control system which is functional automatically to disable the operation of the first and/or second actuator device which would increase longitudinal instability in the event that a predetermined machine longitudinal instability is sensed, characterised in that the method includes sensing a parameter relating to the travelling speed of the machine on the ground, and where the machine is determined to be travelling at a speed above a threshold speed, disabling the longitudinal load moment control system.

[0008] By virtue of the invention, a machine is provided in which the longitudinal load moment control system is operational to protect against excess longitudinal instability beyond the predetermined instability during loading and unloading operations when the machine is stationary or at least travelling at below the threshold speed, thus to protect the machine against overturning. However when the machine travels at above the threshold speed, the load moment control system is disabled, so that the working arm can be raised or lowered or extended without the operation of any actuator being disabled by the longitudinal load moment control system. Even though the longitudinal load movement control system may be disabled, the load movement indicator will continue to provide a visual indication to the operator of the longitudinal stability status of the machine.

[0009] Thus in for example a construction site context, when loading and unloading is only permitted when the machine is stationary, and the machine may only travel when loaded with the working arm in a lowered and retracted condition, full safety is provided. In an agricultural context, the operator may use the machine without the load moment control system operating such as to affect his ability to operate the first and second actuator devices.

[0010] In one example the working machine is of the kind in which the working arm is a loading arm which is pivoted relative to the main structure for up and down movement about a generally horizontal axis, at the one end of the working arm, typically at a rear position on the main structure, the working arm extending forwardly beyond the main structure at the other end, where the working implement: is provided. The first actuator device (which may include one or a plurality of actuators) may extend between the main structure and the loading arm, the first actuator device being extendable to raise the arm and retractable to lower the arm, whilst the longitudinal load moment is sensed. The loading arm may be telescopic, having a plurality of arm sections, the second actuator devices (which again may include one or a plurality of actuators) extending between adjacent sections of the arm, which second actuator device is extendable or retractable to extend or retract the loading arm, whilst sensing the longitudinal load moment.

[0011] The first and second actuator devices may be provided in a hydraulic circuit which includes a longitudinal load moment control system device which is operable under the control of a controller, to prevent the flow of hydraulic fluid to or from one of or each of the actuator devices when the longitudinal load moment control system is operational and longitudinal instability is sensed which is greater than the predetermined machine longitudinal instability.

[0012] Preferably the method may include sensing the travelling speed of the machine on the ground by sensing movement of the machine relative to the ground, e.g. using a ground speed radar, or the speed of the machine may be sensed by sensing movement of a part of the ground engaging drive structure which moves as the machine moves on the ground, e.g. a wheel or axle rotation, so that whether the machine is driven or coasting, the method of the invention may be performed. However the method may include sensing the movement of a transmission component, such as the engagement of a clutch element or gear of the transmission, or the rotational speed of a transmission component such as a gear or shaft, to determine whether the travelling speed of the machine over the ground is above or below the threshold speed. Further alternatively, the braking status of the machine may be sensed, or movement of a component of a foot brake, or a parking brake. In each case the method may include providing a signal to a controller indicative of the machine travelling speed, the controller disabling the longitudinal load moment control system when the travelling speed is determined to be above the threshold speed.

[0013] In one example, the threshold speed may be zero kph, but in any event is preferably less than 5 kph and more preferably is not more than 0.5 kph.

[0014] According to a second aspect of the invention we provide a working machine which includes a main structure and a working arm, the working arm being pivotally mounted on the main structure, at one end of the arm, the working arm being raisable and lowerable relative to the main structure by a first actuator device, and being extendible relative to the main structure by a second actuator device, and the arm carrying in use at its other end a working implement which in use carries a load, the machine further including a ground engaging drive structure by which the machine is driveable on the ground, and the machine having a longitudinal load moment control system which is functional automatically to disable the operation of the first and/or second actuator device which would increase longitudinal instability in the event that a predetermined machine longitudinal instability is sensed, characterised in that the machine further includes a sensor to sense a parameter relating to the travelling speed of the machine on the ground, and to provide a signal to a controller indicative of whether the travelling speed of the machine is above or below a threshold speed, and where the machine is determined to be travelling at a speed above a threshold speed, the controller disabling the longitudinal load moment control system.

[0015] Embodiments of the invention will now be described with reference to the accompanying drawings in which:-

FIGURE 1 is a side illustrative view of a working machine which may be operated in accordance with the invention, showing a working arm in various alternative conditions;

FIGURE 2 is a rear view of the machine of figure 1 but showing the working arm in a single condition;

FIGURE 3 is a diagram of a part of a hydraulic circuit of the machine of figure 1 and 2.

[0016] Referring to figure 1 a working machine 10 is shown which in the example is a loading machine having a main structure which is a body 11, on which is mounted at a rear position of the body 11, one end 13 of a working arm 14, for pivoting movement of the arm 14 about a generally horizontal axis B relative to the body 11. The arm 14 is raisable and lowerable about the axis B by virtue of a first actuator device 12 which may include one or a plurality of preferably double acting hydraulic actuators.

[0017] The arm 14 is also extendable and retractable by virtue of having a plurality (only two in the example in the drawings) of telescopic sections 14a, 14b, there being a second actuator device 15, which again may be one or a plurality of preferably double acting hydraulic actuators, to effect relative extension and retraction of the arm sections 14a, 14b.

[0018] In figure 1 the arm 14 is illustrated in a fully lowered and retracted condition, and a raised and extended condition.

[0019] At its outermost end, i.e. the end of the arm 14 remote from the pivot axis B, the arm 14 carries a working implement 16 which in the example shown, is a loading forks 16. The forks 16 are shown carrying a load L. The loading forks 16 are pivotal relative to the arm 14 about a generally horizontal axis D by another actuator device indicate at 17.

[0020] The arm 14 is mounted about axis B at a rear end of the body 11 and extends forwardly of a front end of the body 11. The body 11 mounts an operators cab 20 from where an operator may control the raising and lowering and extension and retraction of the working arm 14, and pivoting of the loading implement 16, using manual controls which operate hydraulic controls valves for the actuator devices 12, 15, 17. Also, from within the cab 20 the operator may drive the machine 10 on the ground, the machine 10 including a ground engaging drive structure to enable this. The ground engaging drive structure includes in this example a front pair of wheels 21 and a rear pair of wheels 22, at least the front wheels 21 being steerable and at least the rear wheels 22 being drivable via a transmission 24 from an engine E.

[0021] The machine 10 includes a longitudinal load moment control system which is effective to protect the machine 10 against overturn due to longitudinal instability during load handling. The control system includes a sensor 30 on a rear axle 19 which carries the rear wheels 22. The rear axle 19 is pivoted to the body 11 for movement about a generally horizontal axis A which is substantially perpendicular to axis B about which the loading arm 14 pivots, and centered on a machine centreline C shown in figure 2. The sensor 30 may include at least one stress gauge which provides an electrical signal to a control system controller 32 as indicated in figure 3. The controller 32 determines from the signal from the load sensor 30 whether the longitudinal load moment is within or not, a safe limit. In another example, the load sensor 30 may only provide a signal to the controller 32 when an unsafe longitudinal load moment is sensed.

[0022] In each case, when an unsafe longitudinal load moment is sensed i.e. a moment greater or less than a predetermined moment, the controller 32 is arranged to respond by automatically disabling the operation of any actuator device 12/15/17 which would increase longitudinal instability further.

[0023] In the illustration in figure 3 there is shown a control valve 34 which receives pressurised hydraulic fluid from a source such as a pump P, and depending upon the operation of a manual control in the cab 20, the control valve 34 directs pressurised hydraulic fluid to an actuator device 12/15/17. The longitudinal load moment control system includes a load safety valve 35 between the control valve 34 and the actuator device 12/15/17, which is electrically operated in this example. In the event that the controller 32 determines that there is longitudinal instability beyond a predetermined longitudinal instability, the load safety valve 35 is closed to prevent the flow of more hydraulic fluid to the actuator device 12/15/17. Thus the machine 10 is protected against any further longitudinal instability which otherwise could occur upon any further actuator device 12/15/17 operation.

[0024] In another example (not shown), instead of the load safety valve 35 being between the control valve 34 and an actuator device 12/15/17, a load safety valve 35 may be provided between the pump P and the control valve 34. Where the control valve 34 is electronically operated or pilot operated, if desired, the longitudinal load moment control system may be incorporated into a system controller which provides an electrical or pilot signal to the control valve 34 in response to the operation of a manual operator control to operate the control valve 34; in normal operation, but which interrupts the signal to the control valve 34 when the sensor 30 senses a longitudinal instability greater than a predetermined instability. Thus a separate load safety valve 35 or similar device, may not be required.

[0025] It will be appreciated that a typical control valve 34 will include a spool which is resiliently biased to a position in which no pressurised hydraulic fluid passes to the downstream actuator 12/15/17. Thus in the absence of an electrical or pilot control signal to move the spool against the resilient biasing, the spool will return to its "no flow" position and the actuating device 12/15/17 will be disabled.

[0026] In the example, it will be appreciated that the longitudinal instability of the machine 10 may increase upon a loaded loading arm 14 being raised and/or extended during a loading or unloading operation, or upon the arm 14 being lowered whilst extended. The longitudinal stability of the machine 10 about a tipping axis which in the example coincides with the rotational axis of the front wheels 21, depends on the load L, and the height, and extension of the loading arm 14, i.e. the distance of the load from the body 11.

[0027] In operation of such a working machine 10 on a construction site for example, typically the machine 10 would be stationary during loading or unloading operations. As desired, one or more (usually a pair) of stabilizers S may be lowered from the body 11 into engagement with the ground to move the tipping axis longitudinally. However in each case the machine 10 is protected against longitudinal instability by the longitudinal load moment control system.

[0028] It will be appreciated that the part of the hydraulic circuit of the machine 10 shown in figure 3 is incomplete and is only included to aid understanding. A practical such circuit would include a plurality of control valves 34, perhaps provided in a common valve block or not, and lines to provide hydraulic fluid to and from both sides of the actuator devices 12/15/17. A plurality of load safety valves 35 may be required to prevent the flow of pressurised fluid to or from one or more or all of the actuator devices 12/15/17, as necessary and desired, to prevent any further increase in longitudinal stability beyond the predetermined safe threshold.

[0029] The longitudinal load moment control system may be more sophisticated than is suggested in the drawings, and may be operational to disable the operation of only a particular actuator device 12/15/17 the operation of which is giving rise to a longitudinal instability machine condition, or the longitudinal load moment control system may operate to reduce the operation of at least one actuator device 12/15/17 at a first threshold of operation, and stop operation of the actuator device 12/15/17 at a second threshold of operation.

[0030] If desired, there may be an input to the controller 32 to indicate when the loading arm 14 has been fully retracted. Upon receipt of such a signal, the longitudinal load moment control system may be disabled, so that as the machine 10 travels on the ground and the longitudinal load moment sensor 30 is subject to transient forces which could falsely indicate longitudinal instability beyond the safe limit; the actuator devices 12/15/17 are not prevented from being operated. Such disabling of the longitudinal load control system may be desirable where e.g. upon closing of the or one of the safety valves 35 or otherwise upon actuation of the longitudinal load movement control system to prevent the flow of fluid to the actuator 12/15/17, a system reset is required, or other special steps need to be taken to restore the hydraulic system to a normal operating condition.

[0031] In accordance with the present invention, the machine 10 includes a sensor 40 to provide an input to the controller 32 indicative of the machine 10 travelling speed on the ground. At its simplest the controller 32 receives a signal from a machine 10 sensor 40 which senses movement of a part of the ground engaging drive structure such as an axle or wheel 19,21,22, which signal at least indicates if the machine 10 travelling speed is above or below a threshold speed. In accordance with the invention such threshold speed is preferably zero kph or close to zero, for example preferably less than 5 kph and more desirably not greater than 0.5 kph.

[0032] In another example, a signal may be provided from a sensor which senses the movement e.g. rotation, of a part of the transmission 24, such as a gear or a shaft of the transmission, or a, not necessarily rotational, movement of an element of a clutch of the transmission 24 during speed and/or ratio selection, or of any other part movement of which is indicative of the travelling speed of the machine 10.

[0033] In another example, the sensor 40 may sense movement of the machine 10 relative to the ground and so may be for example, a component of a ground speed radar.

[0034] In yet another example the sensor 40 may sense movement or operation of another machine 10 part which is dependent upon travelling speed, such as of a part of a braking system of the machine 10, e.g. of the machine foot brake or parking brake, or otherwise the braking status of the machine may give an indication of machine 10 travelling speed.

[0035] In each case the controller 32 may respond to the signal to determine the travelling speed, or the speed indication sensor 40 may only signal the controller 32 upon the travelling speed being determined to be above or below the threshold value. In every case, the controller 32 is responsive to a machine 10 travelling speed above a threshold speed.

[0036] Where the travelling speed is determined by the controller 32 to be less than the threshold speed, the longitudinal load moment control system remains fully operational as described above to protect the machine 10 when an unsafe longitudinal load moment is determined.

[0037] However when travelling speed is determined to be above the threshold speed, in accordance with the present invention, irrespective of whether the loading arm 14 is raised or lowered, or retracted or not, the controller 32 disables the longitudinal load moment control system, permitting the operator to operate the actuator devices 12/15/17 at will.

[0038] In any event, a load movement indicator 31 which is provided in the cab 20 will remain fully operational to indicate to the operator the longitudinal stability status of the machine 10, so even when the longitudinal load movement control system is disabled. Thus the operator may still be made aware of any impending longitudinal instability. Such an indicator 31 typically includes a plurality of indicator lights an increasing number of which are lit as machine instability increases, and possibility with there being an audible alarm as an impending instability condition is determined.

[0039] It will be appreciated that the machine 10 depicted in figure 1 and figure 2 is purely exemplary. Instead of a loading forks 16, another kind of working implement 16 could be provided, such as a loading or even an excavating bucket. The working arm 14 need not be a loading arm as shown, but could, be another kind of loading arm such as a backhoe used for excavating. Where the working arm 14 is a loading arm, the arm may be mounted at the front instead of the rear of the machine body 11 or elsewhere on the body 11. The working arm 14 may carry a hook or magnet for raising the load cranewise, and need not be telescopic as described.

[0040] The longitudinal load moment sensor 30 need not be provided on the rear axle 19, but may be provided by an alternative type of sensor and/or in an alternative position provided that the sensor 30 is able to determine the longitudinal load moment and provide an appropriate signal to the controller 32 by means of which the controller 32 can determine whether or not the longitudinal load moment of the machine 10 is or is not within a safe limit, i.e. less than a predetermined instability.

[0041] The ground engaging drive structure need not include two pairs of wheels 20, 21 but may include one or more pairs of tracks. The transmission 24 may be mechanical and/or hydrostatic as desired.

[0042] The cab 20 need not be mounted on the body 11 as shown that is the rear of the body 11 and at one side of the working arm 14 but may be mounted elsewhere. The machine 10 may have more than one working arm 14, and thus may be of the kind of working machine knows as a backhoe loader.

[0043] Desirably, or indeed necessarily to comply with legislation in some territories, the machine 10 may include a longitudinal movement indicator at least to provide a warning to an operator of an impending longitudinal unstable condition. If, in accordance with the method of the invention, the longitudinal load movement control system is disabled, the load movement indicator may continue to provide a visual indication to the operator of the longitudinal stability status of the machine 10.

Claims

1. A method of operating a working machine (10) which includes a main structure (11) and a working arm (14), the working arm (14) being pivotably mounted on the main structure (11) at one end (13) of the arm (14), the working arm (14) being raisable and lowerable relative to the main structure (11) by a first actuator device (12), and being extendible relative to the main structure (11) by a second actuator device (15), and the arm (14) carrying in use at its other end a working implement (16) which in use carries a load (L), the machine (10) further including a ground engaging drive structure (21, 22) by which the machine (10) is driveable on the ground, and the machine (10) having a longitudinal load moment control system (30, 32, 35, 40) which is functional automatically to disable the operation of the first and/or second actuator device (12, 15) which would increase longitudinal instability in the event that a predetermined machine (10) longitudinal instability is sensed, characterised in that the method includes sensing a parameter relating to the travelling speed of the machine (10) on the ground, and where the machine. (10) is determined to be travelling at a speed above a threshold speed, disabling the longitudinal load moment control system (30, 32, 35, 40).

2. A method according to claim 1 characterised in that the working arm (14) is a loading arm which is pivoted relative to the main structure for up and down movement about a generally horizontal axis (B), at the one end (13) of the working arm (14), at a rear position on the main structure (11), the working arm (14) extending forwardly beyond the main structure (11) at the other end, where the working implement (16) is provided, the first actuator device (12) extending between the main structure (11) and the loading arm (14), the first actuator device (12) being extendable to raise the arm (14) and retractable to lower the arm (14), the method including extending or retracting the first actuator device (12) and sensing the longitudinal load moment.

3. A method according to claim 1 :or claim 2 characterised in that the loading arm (14) is telescopic, having a plurality of arm sections (14a, 14b), the second actuator device (15) extending between adjacent sections (14a, 14b) of the arm (14), which second actuator device (15) is extendable or retractable to extend or retract the loading arm (14), the method including extending or retracting the second actuator device (15), and sensing the longitudinal load moment.

4. Method according to any one: of the preceding claims characterised in that the first and second actuator devices (12, 15) are provided in a hydraulic circuit which includes a longitudinal load moment control system device (35) the method including operating the longitudinal load moment control system device (35) under the control of a controller (32), to prevent the flow of hydraulic fluid to or from one of or each of the actuator devices (12, 15) when the longitudinal load moment control system (30, 32, 35, 40)is operational and longitudinal instability is sensed which is greater than the predetermined machine longitudinal instability.

5. A method according to any one of the preceding claims characterised in that the method includes sensing movement of the machine (10) relative to the ground to sense machine travelling speed.

6. A method according to any one of claims 1 to 4 characterised in that the method includes sensing the speed of the machine on the ground by sensing movement of a rotational part of the ground engaging drive structure (21, 22) which moves as the machine (10) moves on the ground.

7. A method according to any one of claims 1 to 4 characterised in that the method includes sensing the movement of a transmission component to determine the traveling speed of the machine (10) on the ground.

8. A method according to claim 7 characterised in that the method includes sensing movement of one of a clutch element, or a gear, or a shaft, to determine the travelling speed of the machine (10) over the ground.

9. A method according to any one of claims 5 to 8 characterised in that the method includes providing a signal to a controller (32) indicative of the machine (10) travelling speed, the controller (32) disabling the longitudinal load moment control system (30, 32, 35, 40) when the travelling speed is determined to be above the threshold speed.

10. A method according to any one of the preceding claims characterised in that the threshold speed is less than 5 kph.

11. A method according to claim 10 characterised in that the threshold speed is not more than 0.5 kph.

12. A method according to claim 11 characterised in that the threshold speed is zero kph.

13. A working machine (10) which includes a main structure (11) and a working arm (14), the working arm (14) being pivotally mounted on the main structure (11) at one end (13) of the arm (14), the working arm (14) being raisable and lowerable relative to the main structure (11) by a first actuator device (12), and being extendible relative to the main structure (11) by a second actuator device (15), and the arm (14) carrying in use at its other end a working implement (16) which in use carries a load (L), the machine (10) further including a ground engaging drive structure (21, 22) by which the machine (10) is driveable on the ground, and the machine (10) having a longitudinal load moment control system (30, 32, 35, 40) which is functional automatically to disable the operation of the first and/or second actuator device (12, 15) which would increase longitudinal instability in the event that a predetermined machine (10) longitudinal instability is sensed, characterised in that the machine (10) further includes a sensor (40) to sense a parameter relating to the travelling speed of the machine (10) on the ground, and to provide a signal to a controller, indicative of whether the travelling speed of the machine (10) is above or below a threshold speed, and where the machine (10) is determined to be travelling at a speed above a threshold speed, the controller (32) disabling the longitudinal load moment control system (30, 32, 35, 40),

Ansprüche

1. Verfahren zum Betreiben einer Arbeitsmaschine (10), die eine Hauptstruktur (11) und einen Arbeitsarm (14) enthält, wobei der Arbeitsarm (14) schwenkbar an der Hauptstruktur (11) an einem Ende (13) des Arms (14) montiert ist, wobei der Arbeitsarm (14) relativ zur Hauptstruktur (11) durch eine erste Betätigungsvorrichtung (12) anhebbar und absenkbar ist und relativ zur Hauptstruktur (11) durch eine zweite Betätigungsvorrichtung (15) ausfahrbar ist und der Arm (14) im Gebrauch an seinem anderen Ende ein Arbeitsgerät (16) trägt, das im Gebrauch eine Last (L) trägt, wobei die Maschine (10) ferner eine mit dem Boden in Eingriff stehende Antriebstruktur (21, 22) enthält, durch welche die Maschine (10) auf dem Boden fahrbar ist, und die Maschine (10) ein Längslastmomentssteuersystem (30, 32, 35, 40) besitzt, das so funktioniert, dass es automatisch den Betrieb der ersten und/oder zweiten Betätigungsvorrichtung (12, 15), welche die Instabilität in Längsrichtung erhöhen würde, in dem Fall abschaltet, dass eine vorgegebene Instabilität der Maschine (10) in Längsrichtung wahrgenommen wird, dadurch gekennzeichnet, dass das Verfahren das Wahrnehmen eines Parameters betreffend die Bewegungsgeschwindigkeit der Maschine (10) auf dem Boden und das Abschalten des Längslastmomentssteuersystems (30, 32, 35, 40), wenn bestimmt wird, dass sich die Maschine (10) mit einer Geschwindigkeit über einer Schwellengeschwindigkeit bewegt, umfasst.

2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass der Arbeitsarm (14) ein Ladearm ist, der zur Auf- und Abbewegung um eine allgemein horizontale Achse (B) relativ zur Hauptstruktur geschwenkt wird, an dem einen Ende (13) des Arbeitsarms (14) an einer hinteren Position der Hauptstruktur (11), wobei sich der Arbeitsarm (14) nach vorne am anderen Ende über die Hauptstruktur (11) hinaus erstreckt, wo das Arbeitsgerät (16) vorgesehen ist, wobei sich die erste Betätigungsvorrichtung (12) zwischen der Hauptstruktur (11) und dem Ladearm (14) erstreckt, wobei die erste Betätigungsvorrichtung (12) ausfahrbar ist, um den Arm (14) anzuheben, und einfahrbar ist, um den Arm (14) abzusenken, wobei das Verfahren das Ausfahren oder Einfahren der ersten Betätigungsvorrichtung (12) und das Wahrnehmen des Längslastmoments einschließt.

3. Verfahren nach Anspruch 1 oder Anspruch 2, dadurch gekennzeichnet, dass der Ladearm (14) teleskopisch ist, wobei er eine Vielzahl von Armteilstücken (14a, 14b) aufweist, wobei sich die zweite Betätigungsvorrichtung (15) zwischen benachbarten Teilstücken (14a, 14b) des Arms (14) erstreckt, welche zweite Betätigungsvorrichtung (15) ausfahrbar oder einfahrbar ist, um den Ladearm (14) auszufahren oder einzufahren, wobei das Verfahren das Ausfahren oder Einfahren der zweite Betätigungsvorrichtung (15) und das Wahrnehmen des Längslastmoments einschließt.

4. Verfahren nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, dass die erste und zweite Betätigungsvorrichtung (12, 15) in einer hydraulischen Schaltung vorgesehen sind, die eine Längslastmomentssteuersystemvorrichtung (35) enthält, wobei das Verfahren das Betreiben der Längslastmomentssteuersystemvorrichtung (35) unter Steuerung einer Steuerung (32) einschließt, um den Fluss von Hydraulikflüssigkeit zu oder von einer oder jeder Betätigungsvorrichtung (12, 15) zu verhindern, wenn das Längslastmomentssteuersystem (30, 32, 35, 40) betrieben wird und eine Instabilität in Längsrichtung wahrgenommen wird, die größer ist als die vorgegebene Instabilität der Maschine in Längsrichtung.

5. Verfahren nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, dass das Verfahren das Wahrnehmen der Bewegung der Maschine (10) relativ zum Boden einschließt, um die Maschinenbewegungsgeschwindigkeit wahrzunehmen.

6. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Verfahren das Wahrnehmen der Bewegung der Maschine auf dem Boden durch Wahrnehmen der Bewegung eines sich drehenden Teils der mit dem Boden in Eingriff stehenden Antriebstruktur (21, 22) einschließt, welches sich bewegt, sowie sich die Maschine (10) auf dem Boden bewegt.

7. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Verfahren das Wahrnehmen der Bewegung einer Transmissionskomponente einschließt, um die Bewegungsgeschwindigkeit der Maschine (10) auf dem Boden zu bestimmen.

8. Verfahren nach Anspruch 7, dadurch gekennzeichnet, dass das Verfahren das Wahrnehmen der Bewegung eines Kupplungselements, eines Zahnrads oder einer Welle einschließt, um die Bewegungsgeschwindigkeit der Maschine (10) auf dem Boden zu bestimmen.

9. Verfahren nach einem der Ansprüche 5 bis 8, dadurch gekennzeichnet, dass das Verfahren das Zuführen eines Signals zu einer Steuerung (32) einschließt, das die Bewegungsgeschwindigkeit der Maschine (10) angibt, wobei die Steuerung (32) das Längslastmomentssteuersystem (30, 32, 35, 40) abschaltet, wenn bestimmt wird, dass die Bewegungsgeschwindigkeit über der Schwellengeschwindigkeit liegt.

10. Verfahren nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, dass die Schwellengeschwindigkeit weniger als 5 km/h beträgt.

11. Verfahren nach Anspruch 10, dadurch gekennzeichnet, dass die Schwellengeschwindigkeit nicht mehr als 0,5 km/h beträgt.

12. Verfahren nach Anspruch 11, dadurch gekennzeichnet, dass die Schwellengeschwindigkeit 0 km/h beträgt.

13. Arbeitsmaschine (10), die eine Hauptstruktur (11) und einen Arbeitsarm (14) enthält, wobei der Arbeitsarm (14) schwenkbar an der Hauptstruktur (11) an einem Ende (13) des Arms (14) montiert ist, wobei der Arbeitsarm (14) relativ zur Hauptstruktur (11) durch eine erste Betätigungsvorrichtung (12) anhebbar und absenkbar ist und relativ zur Hauptstruktur (11) durch eine zweite Betätigungsvorrichtung (15) ausfahrbar ist und der Arm (14) im Gebrauch an seinem anderen Ende ein Arbeitsgerät (16) trägt, das im Gebrauch eine Last (L) trägt, wobei die Maschine (10) ferner eine mit dem Boden in Eingriff stehende Antriebsstruktur (21, 22) enthält, durch welche die Maschine (10) auf dem Boden fahrbar ist, und die Maschine (10) ein Längslastmomentssteuersystem (30, 32, 35, 40) besitzt, das so funktioniert, dass es automatisch den Betrieb der ersten und/oder zweiten Betätigungsvorrichtung (12, 15), welche die Instabilität in Längsrichtung erhöhen würde, in dem Fall abschaltet, dass eine vorgegebene Instabilität der Maschine (10) in Längsrichtung wahrgenommen wird, dadurch gekennzeichnet, dass die Maschine (10) ferner einen Sensor (40) zum Wahrnehmen eines Parameters betreffend die Bewegungsgeschwindigkeit der Maschine (10) auf dem Boden und zum Bereitstellen eines Signals zu einer Steuerung enthält, welches angibt, ob die Bewegungsgeschwindigkeit der Maschine (10) über oder unter einer Schwellengeschwindigkeit liegt, und wobei die Steuerung (32) das Längslastmomentssteuersystem (30, 32, 35, 40) abschaltet, wenn bestimmt wird, dass sich die Maschine (10) mit einer Geschwindigkeit über einer Schwellengeschwindigkeit bewegt.

Revendications

1. Procédé de conduite d'une machine de travail (10) qui comprend une structure principale (11) et un bras de travail (14), le bras de travail (14) étant monté pivotable sur la structure principale (11), à une extrémité (13) du bras (14), le bras de travail (14) étant relevable et abaissable par rapport à la structure principale (11) par un premier dispositif actionneur (12) et extensible par rapport à la structure principale (11) par un second dispositif actionneur (15), et le bras (14) portant, en service, à son autre extrémité, un outil de travail (16) qui, en service, porte une charge (L), la machine (10) comprenant, en outre, une structure motrice en prise avec le sol (21, 22), au moyen de laquelle elle peut être conduite sur le sol, et possédant un système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40) qui est opérationnel automatiquement pour mettre hors service le premier et/ou second dispositif actionneur (12, 15) qui augmenterait l'instabilité longitudinale dans le cas où une instabilité longitudinale prédéterminée de la machine (10) est détectée, caractérisé en ce que le procédé comprend la détection d'un paramètre en rapport avec la vitesse de déplacement de la machine (10) sur le sol, et dans lequel il est déterminé que la machine (10) se déplace à une vitesse supérieure à la vitesse seuil, mettant hors service le système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40).

2. Procédé suivant la revendication 1, caractérisé en ce que le bras de travail (14) est un bras de chargement qui est pivoté par rapport à la structure principale pour effectuer un mouvement vers le haut et vers le bas autour d'un axe généralement horizontal (B), à une de ses extrémités (13) et dans une position arrière sur la structure principale (11), le bras de travail (14) s'étendant vers l'avant sous la structure principale (11), à l'autre extrémité, à laquelle l'outil de travail (16) est prévu, le premier dispositif actionneur (12) s'étendant entre la structure principale (11) et le bras de chargement (14), le premier dispositif actionneur (12) étant extensible pour relever le bras (14) et rétractable pour abaisser le bras (14), le procédé comprenant l'extension ou la rétraction du premier dispositif actionneur (12) et la détection du moment de la charge par rapport à l'axe d'orientation longitudinal.

3. Procédé suivant la revendication 1 ou 2, caractérisé en ce que le bras de chargement (14) est télescopique et présente une pluralité de sections de bras (14a, 14b), le second dispositif actionneur (15) s'étendant entre des sections adjacentes (14a, 14b) du bras (14) et étant extensible ou rétractable pour étendre ou rétracter le bras de chargement (14), le procédé comprenant l'extension ou la rétraction du second dispositif actionneur (15) et la détection du moment de la charge par rapport à l'axe d'orientation longitudinal.

4. Procédé suivant une quelconque des revendications précédentes caractérisé en ce que les premier et second dispositifs actionneurs (12, 15) sont prévus dans un circuit hydraulique qui comprend un dispositif à système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (35), procédé comprenant la conduite du dispositif à système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (35) sous le contrôle d'un contrôleur (32), afin d'empêcher le flux de fluide hydraulique vers ou depuis l'un ou chacun des dispositifs actionneurs (12, 15), lorsque le système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40) est en service et qu'une instabilité longitudinale est détectée, qui est supérieure à l'instabilité longitudinale prédéterminée de la machine.

5. Procédé suivant une quelconque des revendications précédentes, caractérisé en ce que le procédé comprend la détection du mouvement de la machine (10) sur sol, afin de détecter la vitesse de déplacement de la machine.

6. Procédé suivant une quelconque des revendications 1 à 4, caractérisé en ce que le procédé comprend la détection de la vitesse de la machine sur le sol en détectant le mouvement d'une pièce rotative de la structure motrice en prise avec le sol (21, 22), pièce qui est en mouvement quand la machine (10) se déplace sur le sol.

7. Procédé suivant une quelconque des revendications 1 à 4, caractérisé en ce qu'il comprend la détection du mouvement d'un organe de transmission, afin de déterminer la vitesse de déplacement de la machine (10) sur le sol.

8. Procédé suivant la revendication 7, caractérisé en ce que le procédé comprend la détection du mouvement d'un parmi un élément d'embrayage, un mécanisme de transmission ou un arbre, afin de déterminer la vitesse de déplacement de la machine (10) sur le sol.

9. Procédé suivant une quelconque des revendications 5 à 8, caractérisé en ce que le procédé comprend l'envoi d'un signal indicatif de la vitesse de déplacement de la machine (10) à un contrôleur (32), qui met hors service le système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40) lorsque la vitesse de déplacement est constatée être supérieure à la vitesse de seuil.

10. Procédé suivant une quelconque des revendications précédentes, caractérisé en ce que la vitesse de seuil est inférieure à 5 km/h.

11. Procédé suivant la revendication 10, caractérisé en ce que la vitesse de seuil n'est pas supérieure à 0,5 km/h.

12. Procédé suivant la revendication 11, caractérisé en ce que la vitesse de seuil est égale à zéro km/h.

13. Machine de travail (10) qui comprend une structure principale (11) et un bras de travail (14), le bras de travail (14) étant monté pivotable sur la structure principale (11), à une extrémité (13) du bras (14), le bras de travail (14) étant relevable et abaissable par rapport à la structure principale (11) par un premier dispositif actionneur (12) et extensible par rapport à la structure principale (11) par un second dispositif actionneur (15), le bras (14) portant, en service, à son autre extrémité, un outil de travail (16), qui, en service, porte une charge (L), la machine (10) comprenant, en outre, une structure motrice en prise avec le sol (21, 22), au moyen de laquelle elle peut être conduite sur le sol, et la machine (10) présentant un système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40) qui est opérationnel automatiquement pour mettre hors service le premier et/ou le second dispositif actionneur (12, 15) qui augmenterait l'instabilité longitudinale dans le cas où une instabilité longitudinale prédéterminée de la machine (10) est détectée, caractérisé en ce que la machine (10) comprend, en plus, un détecteur (40) pour détecter un paramètre en rapport avec la vitesse de déplacement de la machine (10) sur le sol et pour envoyer un signal indicatif de ce que la vitesse de déplacement de la machine (10) est supérieure ou inférieure à une vitesse de seuil à un contrôleur, et dans lequel il est déterminé que la machine se déplace à une vitesse supérieure à la vitesse de seuil, le contrôleur (32) mettant hors service le système de commande du moment de la charge par rapport à l'axe d'orientation longitudinal (30, 32, 35, 40).

Drawing