MOBILE WORK MACHINE

Description

[0001] The present invention relates to a mobile work machine, in particular an excavator or the like.

[0002] Mobile work machines often have a larger chassis with large diameter tires (or even a track drive) so that they can find a secure footing even in rough and unpaved terrain and can move reliably even under these difficult conditions.

[0003] This means that the operator's cab is usually located above the undercarriage, resulting in a considerable height above ground level. This is clearly evident in the example of an excavator, as the undercarriage is initially designed with the undercarriage (tracked or wheeled), and the operator's cab is located on the uppercarriage, which can rotate relative to the undercarriage. Depending on the dimensions of the excavator, the operator's cab may be positioned significantly (up to several meters) above ground level.

[0004] As a result, an operator of a mobile work machine typically uses a downward angled view from their cab while working, in order to visually survey the ground area directly in front of the cab. To ensure good visibility of the work area, the cabs of mobile work machines feature large glass areas that help ensure the best possible view from the cab.

[0005] However, due to legal requirements in many countries, it is necessary for a steering wheel or similar device to be located in the center of the driver's cab in front of the driver's seat, which the operator of the mobile work machine can use to communicate changes in direction. A steering wheel is common for travel on public roads. In actual use of the mobile work machine on a construction site, however, the mobile work machine is often not controlled using the steering wheel, but rather with a secondary steering system, namely a joystick. This offers the advantage that, in conjunction with the steering via the joystick, combined control of the chassis, a rotational movement of the upper carriage and the tool provided on the upper carriage, for example an excavator arm or the like, is possible.It is therefore also possible to transmit the steering commands entered via the primary steering system using the secondary steering system, although this is usually done in a less intuitive way than with the primary steering system.

[0006] During operation of a mobile work machine, visibility is often restricted in the vicinity of the driver's cab because the primary steering is located directly in the operator's preferred field of vision.

[0007] US2021316778A1 discloses a work machine in which a steering wheel assembly can be moved to the side next to the driver's seat to improve visibility. Furthermore, US2019152505A1 discloses a steering wheel assembly of an autonomously operable vehicle that can be stowed under the driver's seat.

[0008] It is the object of the present invention to provide a mobile work machine that enables an improved view for the operator of a mobile work machine from the driver's cab.

[0009] This is achieved with a mobile work machine that has all the features of claim 1. Advantageous embodiments of the present invention can be found in the subclaims.

[0010] According to the invention, it is provided that the mobile work machine, in particular an excavator, comprises a driver's cab for accommodating an operator of the mobile work machine, an operating station for the operator arranged in the driver's cab, in particular a seat, a primary steering arranged in front of the operating station in the direction of travel of the mobile work machine, in particular a steering wheel, and a secondary steering arranged laterally offset from the operating station in the direction of travel of the mobile work machine, in particular a joystick.The mobile work machine is characterized in that the primary steering has a steering column section which cooperates with a steering column holder in order to transmit a steering actuation to a control unit which implements the desired steering movement, wherein the steering column section and the steering column holder can be connected to one another in a rotationally fixed manner via a plug connection, so that the operator is able to dismantle or remove the primary steering depending on a perceived restriction of visibility.

[0011] According to the invention, it is therefore possible to unplug the primary steering, for example a steering wheel with a steering column section firmly connected to it, from a steering column holder using a plug connection and to store it in a place that does not obstruct the line of sight from the driver's cab during a work process that requires particularly good visibility in the vicinity of the front cab.

[0012] The control commands that were previously entered via the primary steering system are then transmitted using the secondary steering system if necessary.

[0013] According to an advantageous modification of the present invention, it can be provided that the plug connection is implemented by means of a quick coupling, which preferably releases the steering column section coupled to the steering column holder by actuating a locking mechanism, for example a foot pedal, preferably in such a way that the steering column section can then be separated from the steering column holder by lifting it down.

[0014] To make disassembly of the primary steering system as easy as possible, the primary steering system and its steering column section are connected to the steering column mount via a quick-release coupling. A quick-release coupling is a type of coupling that can be opened and closed by the operator without the need for tools. In this case, for example, the quick-release coupling can be designed so that the coupling between the steering column mount and the steering column section can be disengaged by operating a foot pedal, which can be attached to the steering column mount or the steering column section, allowing the operator to remove the primary steering system with a lifting movement. The advantage of releasing the system using a foot pedal is that the operator has two hands available to lift the steering wheel, allowing it to be safely removed from the steering column mount and then immediately taken to a temporary storage location.

[0015] According to a further development of the present invention, it can be provided that the driver's cab has a floor area from which the steering column holder extends upwards.

[0016] The driver's cab usually has a floor plate or floor area that serves as the base for the components contained within the driver's cab. For example, a driver's seat or the steering column mount is arranged on the floor plate or floor area. In mobile machines, the steering column typically extends from the floor area of ​​the driver's cab and is connected to a steering wheel at the end facing away from the ground so that the operator of the mobile machine can intuitively input steering actions by turning the steering wheel. Essentially, it can therefore be provided that, starting from the steering wheel, the rod-like steering column or the steering column section and the steering column mount extend towards the floor and pierce the floor area so that the steering signal can be recorded in an area arranged below the floor area or floor plate of the driver's cab.

[0017] Preferably, the steering column mount can protrude less than 30 cm, preferably less than 20 cm, and more preferably less than 10 cm from the floor area of ​​the driver's cab. It is advantageous if the mount protrudes as little as possible from the floor area.

[0018] It is advantageous if the steering column mount, with which the steering column section of the primary steering can optionally interact, does not protrude too far from the floor area into the interior of the driver's cab when the primary steering is disassembled. Otherwise, the operator's field of vision would be restricted and there would be a risk of injury to the operator when the steering column and steering wheel are disassembled. For this reason, it is desirable to limit the height of the steering column mount that protrudes into the interior of the driver's cab to less than 30 cm.

[0019] Furthermore, it can be provided that the steering column mount, i.e. the non-removable section, has a pivoting device between the floor area of ​​the driver's cab and the area for connecting the steering column section, with which the operator can tilt the primary steering in a desired direction when the primary steering is connected. It is therefore not absolutely necessary for the steering column section and the steering column mount to have a consistently straight shape when connected, since a bent shape is also possible thanks to the pivoting device. This is advantageous because it allows the operator to tilt the primary steering according to their needs in order to achieve the most comfortable position possible.

[0020] According to an optional development of the present invention, it can be provided that the driver's cab has a windscreen which preferably extends to a floor area of ​​the driver's cab.

[0021] The windshield, which extends to the floor, provides the operator with sufficient visibility from their seat into the immediate vicinity of the mobile work machine. The windshield can extend all the way to the floor or the floor panel of the driver's cab. It is also possible for parts of the floor panel to have a window or even be part of the windshield. This is possible, for example, if the windshield is bent in the transition area between the floor panel and the windshield, thus forming part of the floor panel.

[0022] According to an advantageous development of the present invention, it can be provided that the rotationally fixed connection of the steering column section and the steering column holder is implemented via a serration.

[0023] The serration enables a simple, non-rotatable connection between two separable elements. For example, the steering column section has the shape of a hollow tube in its connecting area, which is provided with a corresponding tooth structure on its inner circumference. The corresponding connecting area of ​​the steering column mount has a complementary design and can have a rod-like or tubular shape, which has a matching tooth structure on its outer circumference. If the hollow tube of the steering column section is then pushed onto the, for example, rod-shaped steering column mount, the respective tooth structures engage with each other, creating a non-rotatable connection.

[0024] Furthermore, according to the present invention, a detection device can be provided which detects whether the steering column section interacts with the steering column holder or is plugged onto it and is properly locked for road travel and transmits a corresponding signal to a machine control system of the mobile work machine.

[0025] The detection device is designed to detect whether the steering column section and the steering column mount are operatively connected to each other, i.e., whether the primary steering mechanism can be actuated. If this is the case, the detection device sends a corresponding signal to a machine control system so that it knows the status of the primary steering mechanism. The detection device can comprise a capacitance sensor, an induction sensor, a tactile sensor, or the like to detect a correctly connected steering column section.

[0026] Preferably, it can be provided that the machine control is designed to limit or reduce a maximum travel speed of the mobile work machine when the signal detected by the detection unit indicates that the steering column section and the steering column holder are separated from each other.

[0027] Since primary steering is the preferred method for controlling the steering angle of the mobile machine's undercarriage, and the option of steering the mobile machine's undercarriage using secondary steering is far less common and intuitive for an operator, it is advantageous to reduce the maximum travel speed of the mobile machine when steering it using secondary steering. This contributes to safety and, in particular, prevents the mobile machine from being operated at high travel speeds, where the use of primary steering is advantageous for safety reasons.

[0028] According to a further development of the present invention, it can further be provided that the machine control is designed to reduce the maximum speed of the mobile work machine to a value that enables safe driving of the vehicle, for example to a value of not more than 20 km / h, preferably not more than 15 km / h and more preferably not more than 12 km / h.

[0029] Furthermore, according to an optional modification of the present invention, it can be provided that the machine control is designed so that, when the signal detected by the detection unit indicates that the steering column section and the steering column holder are operatively connected to one another, a limitation of the maximum travel speed of the mobile work machine is not provided or is removed.

[0030] Any limitation of the maximum driving speed is therefore lifted when the detection device detects that the primary steering is functional.

[0031] According to an optional modification of the present invention, the steering column mount can be configured as a shaft with radially circumferential serrations in the contact area with the steering column section. Serrations represent a particularly advantageous option for implementing a rotationally fixed connection between two shaft sections (steering column section and steering column mount) that can be coupled to one another.

[0032] For example, according to the invention, the steering column section can be designed as a hollow shaft in the contact area with the steering column mount, which is provided with a serration on its inner circumference, with this serration preferably being matched to a serration on the steering column section. Of course, the mount does not necessarily have to be a hollow shaft. In principle, the hollow shaft could also be provided in the steering wheel, and the power take-off shaft could be provided on the mount. This would have advantages with regard to the problem of contamination.

[0033] Furthermore, a locking unit can be provided that prevents any relative movement—for example, in the axial direction—of the steering column section relative to the steering column mount after the steering column section has been plugged onto the steering column mount. This locking unit prevents the primary steering from being accidentally removed from the steering column mount.

[0034] Advantageously, according to a further embodiment of the present invention, it can be provided that the locking unit has pins projecting laterally to the longitudinal extent of the steering column receptacle and / or the steering column section for hooking in a locking lug.

[0035] The pins can serve as an attachment point for the other part to be plugged in. It is also conceivable that the plug-in part, which is intended to interact with the pins, has at least one labyrinth-like opening into which the pins are threaded, making removal impossible. Another option is the use of locking lugs, which are preloaded, for example, by a spring and are deflected against their preload force when plugged in, so that after the plugging process is complete, each locking lug engages behind a corresponding pin.

[0036] Accordingly, it can also be provided that the locking unit has a spring-loaded locking lug on the steering column holder and / or on the steering column section in order to cause the steering column section to lock with the steering column holder when the steering column section is plugged onto the steering column holder.

[0037] Further details, features, and advances of the invention will become apparent from the following description of the figures. These show: Fig. 1: a perspective view of the field of vision of the operator of a mobile work machine from the driver's cab, Fig. 2: a perspective view of the field of vision of the operator of a mobile work machine from the driver's cab, in which the steering wheel is connected to an associated steering column section, Fig. 3: a detailed view in the connection area of ​​the steering column section and the steering column holder, and Fig. 4: a detailed view in the connection area of ​​the steering column section and the steering column holder, in which the steering column section is connected to the steering column holder.

[0038] Fig. 1 shows a perspective view of the field of vision of an operator from the driver's cab 1 of a mobile work machine. It is assumed that the operator of the mobile work machine is sitting in the seat of the driver's cab and is looking forward and down out of the cab. It can be seen that the view of the surroundings of the driver's cab 1 in the front area of ​​the driver's cab 1 is provided by the windscreen 2. To the left and right of the operator, there are also large window areas so that the operator's all-round visibility is restricted as little as possible. Furthermore, it can be seen that the driver's cab has a floor area 3 on which foot pedals 4 are provided for controlling the mobile work machine. In road driving mode, for example, the right foot pedal 4 can take on the function of an accelerator pedal, whereas the left foot pedal 4 takes on the function of a brake. Furthermore, in the right area of ​​the Fig. 1 shown field of view a display unit 5 on which information about the status of the mobile work machine can be displayed.

[0039] Furthermore, the primary steering system 6 is located centrally, directly in front of the driver's seat. It is used to input a steering command to the mobile work machine. The primary steering system 6 comprises a steering wheel, which transmits a steering movement via a steering column 7 connected to the steering wheel.

[0040] In addition, one can see in the lower edge area of ​​the Fig. 1 on both the left and right side there is a secondary steering 8, which in this case is designed as a joystick.

[0041] It is clear how much the primary steering 6 in the form of the steering wheel restricts the field of vision of the mobile work machine operator, as it obstructs an unobstructed view of the ground area directly in front of the driver's cab. The primary steering restricts the field of vision in the immediate vicinity of the mobile work machine. Also visible is the excavator bucket 9 belonging to the mobile work machine, which has been illustrated as an example of a working tool of the mobile work machine.

[0042] Fig. 2 now shows the same field of vision from the operator located in the driver's cab 1, but according to the inventive idea the primary steering 6 has been blocked off, whereby the field of vision of the operator in the driver's cab 1 is significantly improved.

[0043] This is immediately noticeable in the significantly improved visibility of the ground area located in front of the driver's cab. For example, the primary steering system 6 no longer obstructs the view on the ground directly in front of the mobile work machine.

[0044] It is clearly evident that the basic idea of ​​the present invention significantly improves the operator's field of vision in the driver's cab 1 and thus provides significant added value. It is clear to those skilled in the art that an improved field of vision is also advantageous with regard to the danger posed by a mobile work machine, since the operator's improved visibility reduces the risk of accidents.

[0045] From the floor area 3 of the driver's cab 1, only the steering column mount 10 protrudes, which is usually significantly less than 30 cm long and does not obstruct the field of vision. Fig. 2 In the state of the mobile work machine shown, a steering actuation, which was previously carried out by the primary steering 6, is carried out by the secondary steering 8. This means that the operator can now transmit a steering movement to the work machine using the joystick 8 instead of the steering wheel 6.

[0046] However, since this is less intuitive than operating a steering wheel 6, for safety reasons, it can be provided that the maximum travel speed of the mobile work machine is reduced or limited in a state in which the primary steering 6 is removed. For this purpose, a detection device is provided which recognizes whether the primary steering 6 is installed or removed. If the primary steering 6 is in a removed state, the detection device reports this to a machine control system, which then limits the maximum travel speed of the mobile work machine in response. For example, it can be provided that in a configuration in which the primary steering 6 is not attached, the travel speed of the mobile work machine cannot exceed 20 km / h.

[0047] Furthermore, it can be provided that upon detection of a dismantled steering wheel 6, the engine control automatically transfers the steering function to the secondary steering without this having to be selected manually by the operator in a selection menu, for example with the aid of the display device 5.

[0048] Fig. 3 shows a possible implementation of the steering column mount 10 and a steering column section 7 connected to it. In the present figure, it can be seen that the two components, i.e. the steering column section 7 and the steering column mount 10, are in engagement with one another, so that a steering movement (e.g. rotational movement) transmitted via the steering wheel 6 is passed on via the steering column mount 10.

[0049] Furthermore, a locking mechanism 11 can be seen, which can be transferred into an unlocked state by means of an unlocking device, in particular a foot pedal 12.

[0050] If this foot pedal 12 of the locking mechanism 11 is actuated, an engagement between the steering column section 7 and the steering column holder 10 is released, so that the operator can lift the primary steering 6 (together with the steering column section 7) from the steering column holder 10.

[0051] Fig. 4 shows a representation in which the steering column mount 10 is separated from the steering column section 7. It can be seen that the steering column mount 10 has a shaft with radially circumferential toothing at the end facing the interior of the driver's cab 1. This serration, in cooperation with the steering column section 7, which can be designed, for example, as a hollow tube with internal toothing in the transition area to the steering column mount 10, serves to create a rotationally fixed connection between the steering column mount 10 and the steering column section 7 in a plugged-on state.

[0052] In order to ensure that the primary steering 6 is not accidentally lifted off the steering column holder 10, a corresponding locking mechanism is provided, which is arranged in the Fig. 3 illustrated implementation interacts with the two pins 13 projecting laterally on the steering column mount 10.

[0053] The locking mechanism can be a labyrinth-like recess in a hollow tube on the steering column section 7, so that after the pins have been plugged in and inserted into the recess, a rotation of the two components prevents the primary steering 6 from being accidentally lifted off. Furthermore, a locking mechanism is also conceivable, which engages the pins 13 on the steering column mount 10 when the steering column section 7 is plugged in.

[0054] Fig. 5 shows a sectional view through a driver's cab 1 of a mobile work machine. On the left side of the driver's cab, the windscreen 2 can be seen, which extends to a floor area 3. From the floor area 3, the steering column mount 10 extends into the interior of the driver's cab 1 (in Fig. 5 concealed by the rubber bellows), onto which the steering column section 7 of the primary steering 6 is attached. To increase the comfort for the operator in the cabin 1, a tilting mechanism can be provided that allows the steering column 7 to be tilted.

[0055] This tilting mechanism is not dismantled when the primary steering 6 is unplugged, but is part of the steering column mount 10. This means that the connection area for attaching the steering column section 7 is located above the tilting mechanism of the steering column mount 10.

[0056] It is also shown that the connecting area between the steering column section 7 and the steering column mount 10 is surrounded by a rubber bellows, which serves as a cover for the connecting area. However, this cover can also be simply attached to the steering column section or the steering column mount 10, so that when the primary steering system 6 is disassembled, the cover in the form of the rubber bellows can also be removed. Furthermore, those skilled in the art will understand that the cover for the connecting area between the steering column section 7 and the steering column mount 10 is not absolutely necessary, so it can be omitted entirely.

[0057] Furthermore, a joystick 8, which can be used as a secondary steering system, can be seen on the side of the operator's seat in the driver's cab 1. Thus, if the primary steering system 6 is removed, the mobile work machine can continue to perform the same steering actions, although these are then input via the secondary steering system 8 rather than the primary steering system 6.

[0058] The invention described above now enables the operator of a mobile work machine to significantly improve their field of vision into the lower front area of ​​the mobile work machine when necessary. This is achieved by being able to dismantle the obstructive steering column along with the attached steering wheel, for example without tools, so that the steering wheel, which was previously directly in the field of vision, no longer obstructs the field of vision. The steering commands previously entered via the steering wheel can then continue to be entered using a secondary steering system, such as a joystick, so that the full functionality of the mobile work machine is guaranteed even when the primary steering system in the form of a steering wheel and a steering column section is dismantled.

[0059] Instead of the installed steering column, a protective cap can be used to protect the remaining steering column stub from dirt, dust, or potential injuries using the same locking or latching function. This protective cap always swaps places with the steering column. If the steering column is mounted in front of the driver, the protective cap is mounted in the compensating position. If, however, the steering column is mounted in the compensating position, the protective cap is mounted in front of the driver.

Claims

1. Mobile working machine, in particular a digger, comprising: a driver's cab (1) for accommodating an operator of the mobile working machine, a control station for the operator, in particular a seat, arranged in the driver's cab, a primary steering system (6), in particular a steering wheel, arranged in front of the control station in the direction of travel of the mobile working machine, and a secondary steering system (8), in particular a joystick, arranged laterally offset from the control station in the direction of travel of the mobile working machine, characterized in that the primary steering system (6) has a steering column section (7), which cooperates with a steering column mount (10) to transmit a steering actuation to a control unit implementing the desired steering movement, wherein the steering column section (7) and the steering column mount (10) can be connected to each other in a rotationally fixed manner via a plug-in connection, such that the operator is able to dismount the primary steering system (6) depending on a perceived visual restriction.

2. Mobile working machine according to the preceding claim 1, wherein the plug-in connection is implemented with the aid of a quick coupling, which preferably releases the steering column section coupled to the steering column mount (10) by actuating a locking mechanism, for example a foot pedal (12), preferably such that the steering column section can then be separated from the steering column mount by lifting it down.

3. Mobile working machine according to any one of the preceding claims, wherein the driver's cab has a floor area (3), from which the steering column mount (10) extends upwards.

4. Mobile working machine according to the preceding claim 3, wherein the steering column mount (10) protrudes less than 30 cm, preferably less than 20 cm, and in a preferred manner less than 10 cm from the floor area (3) of the driver's cab.

5. Mobile working machine according to any one of the preceding claims, wherein the driver's cab has a windscreen (2), which preferably extends to a floor area (3) of the driver's cab.

6. Mobile working machine according to any one of the preceding claims, wherein the rotationally fixed connection of the steering column section (7) and the steering column mount (10) is implemented via a form-fitting connection, e.g. a serrated toothing.

7. Mobile working machine according to any one of the preceding claims, wherein a detection device is provided, which detects whether the steering column section (7) cooperates with or is plugged onto the steering column mount (10) and transmits a corresponding signal to a machine control of the mobile working machine.

8. Mobile working machine according to the preceding claim 7, wherein the machine control is designed to reduce a maximum travel speed of the mobile working machine when the signal detected by the detection indicates that the steering column section (7) and the steering column mount (10) are separated from each other.

9. Mobile working machine according to the preceding claim 8, wherein the machine control is designed to reduce the maximum travel speed of the mobile working machine to a value of at most 20 km / h, preferably at most 15 km / h, and in a preferred manner at most 12 km / h.

10. Mobile working machine according to any one of the preceding claims 7-9, wherein the machine control is designed not to provide or to remove a restriction on the maximum travel speed of the mobile working machine when the signal detected by the detection indicates that the steering column section (7) and the steering column mount (10) are operatively connected.

11. Mobile working machine according to any one of the preceding claims, wherein the steering column mount (10) has, in the contact area with the steering column section (7), the configuration of a shaft with form-fitting elements, for example radially circumferential serrated toothing.

12. Mobile working machine according to any one of the preceding claims, wherein the steering column section (7) has, in the contact area with the steering column mount (10), the configuration of a hollow shaft, which is provided with a serrated toothing on its inner circumference, wherein this serrated toothing is preferably matched to a serrated toothing of the steering column mount.

13. Mobile working machine according to any one of the preceding claims, wherein a locking unit is provided, which, once the steering column section (7) has been plugged onto the steering column mount (10), prevents all relative movements of the steering column section with respect to the steering column mount.

14. Mobile working machine according to any one of the preceding claims 12 or 13, wherein the locking unit has pins projecting laterally to the longitudinal extent of the steering column mount (10) and / or the steering column section (7) for hooking a latching lug.

15. Mobile working machine according to any one of the preceding claims 12-14, wherein the locking unit has a spring-biased latching lug on the steering column mount (10) and / or on the steering column section (7) in order to effect latching of the steering column section with the steering column mount when the steering column section is plugged onto the steering column mount.