HYDRAULIC ARRANGEMENT

Abstract

The invention relates to a method (100) of operating an actuator arrangement including at least two types of actuators (6, 7, 11, 12, 30, 34) effectuating different types of movement of a connected device (10, 32) to be actuated, where a change of attitude of the connected device (10, 32) has an influence on the position of at least a defined part (13, 14) of the connected device (10, 32). Different types of actuators (6, 7, 11, 12, 30, 34) are actuated in an automated way to at least partly compensate for the change of position of the defined part (13, 14) of the connected device (10, 32) when changing the attitude of the connected device (10, 32), at least for a certain range of movements.

Claims

1. A method of operating an actuator arrangement comprising at least two types of actuators effectuating different types of movement of a connected device to be actuated, where a change of attitude and/or position of the connected device has an influence on the position of at least a defined part of the connected device, wherein the different types of actuators are actuated in an automated way to at least partly compensate for the change of position of the defined part of the connected device, when changing the attitude and/or position of the connected device, at least for a certain range of movement.

2. The method according to claim 1, wherein the attitude of the connected device is primarily determined by the setting of an attitude actuator, wherein the setting of the attitude actuator usually has an influence on the position of the defined part of the connected device as well.

3. The method according to claim 1, wherein at least some of said actuators are hydraulic actuators, in particular hydraulic pistons and/or hydraulic motors and/or in that at least one of said actuators is a driving actuator of a vehicle.

4. The method according to claim 1, wherein the connected device is a shovel, a bucket, a fork, and/or a grasping device and/or in that the actuated arrangement forms part of a shovel dozer, a wheel loader, a telescopic wheel loader, a teleloader, a backhoe loader, an excavator and/or a forklift truck.

5. The method according to claim 1, wherein the defined part of the connected device is located near a bottom side of the connected device and/or is located near a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from the connection section and/or the hinge device of the connected device and the actuated arrangement.

6. The method according to claim 5, wherein the defined part of the connected device is chosen in dependence of the connected device.

7. The method according to claim 1, wherein the range for corrections and/or the direction of corrections is limited for certain actuators, in particular for safety reasons and/or in that corrections of at least certain actuators are only allowed under certain conditions and/or on condition of an express clearance and/or on condition of a certain sensor input and/or on condition of a certain data output and/or in certain areas and/or locations.

8. The method according to claim 1, wherein the method is applied on request only, in particular on request of an operator and/or in that the method is deactivated on request, in particular on request of an operator.

9. The method according to claim 1, wherein the main input is made by an operator, in particular a human operator and/or an autonomous driving logic, wherein the main input is modified using a method according to claim 1.

10. A controller device, in particular electronic controller device that is designed and arranged to perform a method according to claim 1.

11. An actuator arrangement, comprising a plurality of actuators and a controller device according to claim 10.

12. A working vehicle, comprising an actuated arrangement according to claim 11.

13. The method according to claim 2, wherein at least some of said actuators are hydraulic actuators, in particular hydraulic pistons and/or hydraulic motors and/or in that at least one of said actuators is a driving actuator of a vehicle.

14. The method according to claim 2, wherein the connected device is a shovel, a bucket, a fork, and/or a grasping device and/or in that the actuated arrangement forms part of a shovel dozer, a wheel loader, a telescopic wheel loader, a teleloader, a backhoe loader, an excavator and/or a forklift truck.

15. The method according to claim 3, wherein the connected device is a shovel, a bucket, a fork, and/or a grasping device and/or in that the actuated arrangement forms part of a shovel dozer, a wheel loader, a telescopic wheel loader, a teleloader, a backhoe loader, an excavator and/or a forklift truck.

16. The method according to claim 2, wherein the defined part of the connected device is located near a bottom side of the connected device and/or is located near a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from the connection section and/or the hinge device of the connected device and the actuated arrangement.

17. The method according to claim 3, wherein the defined part of the connected device is located near a bottom side of the connected device and/or is located near a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from the connection section and/or the hinge device of the connected device and the actuated arrangement.

18. The method according to claim 4, wherein the defined part of the connected device is located near a bottom side of the connected device and/or is located near a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from a front section of the connected device, preferably opposite of a connection section and/or a hinge device of the connected device and the actuated arrangement and/or is located with a displacement from the connection section and/or the hinge device of the connected device and the actuated arrangement.

19. The method according to claim 1, wherein the defined part of the connected device is chosen in dependence of the connected device.

20. The method according to claim 2, wherein the defined part of the connected device is chosen in dependence of the connected device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Further advantages, features, and objects of the invention will be apparent from the following detailed description of the invention in conjunction with the associated drawings, wherein the drawings show:

[0035] FIG. 1: a schematic view of a teleloader from a side;

[0036] FIG. 2: the hydraulic schematics of the teleloader of FIG. 1 in a schematic drawing;

[0037] FIG. 3: the schematics of a control method for the teleloader according to FIGS. 1 and 2;

[0038] FIG. 4: a schematic side view of a bucket loader.

DETAILED DESCRIPTION

[0039] FIG. 1 shows a telescopic wheel loader 1 in a schematic side view. Teleloaders 1 as such are well known in the art.

[0040] As usual, the teleloader 1 comprises a chassis 2 that is presently mounted on four wheels 3. Thanks to the wheels 3 the teleloader 1 can be moved around by an operator sitting in the driver's cab 4 of the teleloader 1. Certainly, the number of wheels 3 can vary. Also, it is possible that instead of wheels 3, crawler chains are used.

[0041] The teleloader 1 has a telescopic boom 5 that can be extended and contracted using an appropriate actuator, presently a hydraulic piston 6 (telescopic piston 6). Certainly, different types of actuators are possible as well, like a hydraulic motor that drives a cog that engages in a cog rail, just to name an example.

[0042] Furthermore, a second hydraulic piston 7 is present (angle variation piston 7) that is used for changing the angle of the telescopic boom 5 with respect to the vehicle chassis 2. For realising this, the telescopic boom 5 is movably attached to the chassis 2 using a hinge section 8.

[0043] Attached to the upper end 9 of telescopic boom 5 there is a fork 10 that can be used for picking up and putting down pallets, bales of straw, or the like. Furthermore, as it is known in the prior art as such as well, the fork 10 is connected to the upper end 9 by a tilting actuator 11 (presently actuated using a hydraulic piston as well; attitude actuator), so that the angle of the fork 10/the fork's arms 14 with respect to the chassis 2 can be varied. Thanks to this ability, pallets can be easily picked up and put down in a horizontal position (with respect to the environment). By tilting the fork 10 into an appropriate position, however, the pallet can be safely fixed on the fork 10, so that it does not fall down when the pallet is moved around by the teleloader 1.

[0044] As it is known in the art, and as it is clear from FIG. 1, an actuation of the angle variation piston 7 will result in a tilting action of the fork 10. In detail, the change of angle of telescopic boom 5 with respect to the chassis 2 is identical to the change of attitude/variation of the angle of fork 10 with respect to the ground (in case the teleloader 1 does not move). This change of attitude/variation can be either compensated by an appropriate manual operation of the operator (manual compensation), or by an automated actuation of the tilting actuator 11 (automated compensation).

[0045] However, an actuation of the angle variation piston 7 will also result in a variation of the horizontal position (x-axis) of the fork 10 (comparatively high influence), as well as in a change of the vertical position (y-axis) of the fork 10 with respect to the ground (comparatively small variation in the presently shown position of telescopic boom 5). It is presently suggested that this variation is automatically compensated (at least in part) by an appropriate actuation of the telescopic boom 5 (appropriate extension/contraction of telescopic piston 6), and/or an appropriate actuation of the wheels 3 that are presently driven by a hydraulic motor 12 (see FIG. 2).

[0046] Similarly, an extraction or contraction of the telescopic boom 5 does not only result in lifting or lowering (y-axis) the fork 10, but also in a certain forward or backward movement of the fork 10 (x-axis), as well. As it is presently suggested, this change may be compensated, at least in part, by an appropriate actuation of the wheels 3. However, it is usually preferred that the compensation of the actuator arrangement is done without actuating the wheels 3. Nevertheless, such an actuation of the wheels 3 might prove to be necessary/advantageous, at least in certain positions of the actuator arrangement.

[0047] Even further, when a tilting command is applied to the tilting actuator 11 of fork 10, this tilting command will also lead to a certain variation of the horizontal and/or vertical position of various parts of the fork 11. For the presently shown teleloader 1, usually the most problematic part is the front tip 13 of the fork arms 14 of fork 10. It is also presently suggested that any change in height (altitude; vertical position; y-axis) and/or horizontal position (x-axis) that occurs due to a tilting movement of fork 10 is automatically compensated by an appropriate actuation of the various other actuators, namely of angle variation piston 7 and/or telescopic piston 6 and/or hydraulic motor 12 (that is driving the wheels 3). Therefore, the front tips 13 of the fork arms 14 remain at an essentially identical position in space, albeit the angular position (attitude) of the fork 10 changes.

[0048] The relevance of this compensation is clear when considering the situation, where an operator has to place a pallet into a position of a shelf: he wants to change the tilted back position that is suitable for driving around into a horizontal position of the fork 10 to be able to place the pallet that is situated on the fork 10 into the shelf. So far, when commanding a tilt-forward action of the fork 10, the operator has to manually apply a lifting action and a backward driving action at the same time, so that the position of the front tip 13 of the fork 10 does not change with respect to the shelf. According to the prior art, this is quite cumbersome and requires a lot of training and experience.

[0049] Thanks to the presently suggested automatic compensation, the operator can simply command a forward tilting movement and the rest of the actuation is done automatically.

[0050] Problems might occur if an experienced user who is accustomed to compensate for any positional variations is first appointed to drive a teleloader 1 according to the present suggestion. To make the customisation process simpler for him, it is possible to define an only partial automatic correction to make the transitional period simpler for him. Therefore, the individual driver might set a 50% automatic correction at the beginning of the shift, while the next day or a week he might increase the automatic correction to 70%, just to give an example. Certainly, another operator can set any setting that he feels comfortable with.

[0051] It is further to be noted that based on the current task, even an overcorrection might be sensible. As an example, an over-correction of 120% might be advantageous, in case a pallet is placed on the fork 10, where the length of the pallet is 20% longer than the fork arms 14 lengths.

[0052] In FIG. 2, the principal hydraulic circuitry 15 is shown in a schematic drawing.

[0053] Hydraulic oil that is used for the various hydraulic services 6, 7, 11, 12, 17, 23 is supplied by a hydraulic pump 16. In the present example, the hydraulic pump 16 services telescopic piston 6, angular variation piston 7, tilting actuator 11 and hydraulic motor 12, and possibly various other systems, like a hydraulic steering system 23, that is presently connected to the hydraulic circuit by means of a priority valve 17 (just to give an example).

[0054] The input of the operator is presently made using a joystick 18 (albeit different devices can be used as well). The input data 19 is delivered to a controller 20.

[0055] Additional input data is received from various sensors 22 that are placed at appropriate positions.

[0056] The operator input data 19 is read in 101 by the controller 20 (see also flowchart diagram 100 of FIG. 3).

[0057] Additionally, additional input data 21 is read in 102 by the controller 20.

[0058] Based on the various input data 19, 21, and based on additional data that is stored in the controller (representing the mechanical design of the teleloader 1, preferences of the present operator and the like), the controller first of all calculates 103 the side effects that come along with a certain actuation command. As an example, in this step the controller 20 considers a tilting command for tilting the fork 10 and calculates the effect this will have on the horizontal (x-axis) and the vertical (y-axis) position of the front tip 13 of the fork 10.

[0059] Next, the controller 20 calculates 104 appropriate compensation signals that will be applied to the various actuators 6, 7, 11, 12, so that no side-effects will occur.

[0060] Possibly, the size of the control signals will be artificially increased or decreased (i.e. the correction signals will be adapted 105), in case the operator, the manufacturer of the vehicle, or any machine shop or employer has implemented this feature.

[0061] Consequently, the controller 20 will output the appropriately corrected actuation signals 106.

[0062] After this, the program jumps back 107 and the flowchart 100 is repeated for a new cycle.

[0063] To complete the description, in FIG. 4 another type of machinery is shown, namely a bucket loader 25 in a schematic side view. In the presently shown detailed embodiments, similar devices are using identical reference numbers, if the function of the respective devices are identical, or at least highly similar.

[0064] Similar to the teleloader 1, the presently shown bucket loader 25 has a chassis 26 that is mounted on wheels 27 (presently four wheels 27). The operator is sitting in the driver's cab 28.

[0065] The bucket loader 25 shows a pivot capable & arranged boom 29. The boom 29 is attached to the chassis 26 by the hinge section 8.

[0066] The boom 29 can be raised or lowered using a hydraulic piston 30 (angle variation piston 30). It is to be noted, that different types of actuators can be used as well.

[0067] At the opposite side of the hinge section 8 (front end 31 of boom 29), presently a bucket 32 is attached. Presently, the bucket 32 is also rotatably attached to the boom 29, using a hinge 33. The attitude of the bucket 32 (angle of the bucket 32 with respect to the ground) can be varied by an attitude actuator 34, which is presently also designed as a hydraulic piston 34.

[0068] The previously said can be applied mutatis mutandis to the presently suggested bucket loader 25 as well. Doing this, the same objectives, advantages and features can be realised as well, at least in analogy.

[0069] While the present disclosure has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this disclosure may be made without departing from the spirit and scope of the present disclosure.