HEAVY-DUTY VEHICLE

Abstract

A heavy-duty vehicle, comprising a steering unit mounted on a vehicle frame of the heavy-duty vehicle, wherein the steering unit is rotatable about an axis of rotation of the steering unit. The heavy-duty vehicle comprises a steering input element connected to the steering unit and configured to cause the steering unit to rotate about the axis of rotation of the steering unit. The steering unit has at least one connecting portion configured to be connected to one or more of a steering device of the heavy-duty vehicle or the steering input element of the heavy-duty vehicle. The steering unit comprises at least one actuating unit configured to change a distance of at least one connecting portion relative to the axis of rotation of the steering unit.

Claims

1. A heavy-duty vehicle, comprising: a steering unit mounted on a vehicle frame of the heavy-duty vehicle, wherein the steering unit is rotatable about an axis of rotation of the steering unit; and a steering input element connected to the steering unit and configured to cause the steering unit to rotate about the axis of rotation of the steering unit, wherein the steering unit has at least one connecting portion configured to be connected to one or more of a steering device of the heavy-duty vehicle or the steering input element of the heavy-duty vehicle, and wherein the steering unit comprises at least one actuating unit configured to change a distance of at least one connecting portion relative to the axis of rotation of the steering unit.

2. The heavy-duty vehicle of claim 1, wherein the steering input element is connected to the steering unit via a coupling unit, wherein the coupling unit is connected to the steering unit eccentrically to the axis of rotation of the steering unit, wherein the coupling unit connects the steering input element to the steering unit so that a displacement of the steering input element relative to the vehicle frame of the heavy-duty vehicle causes a rotation of the steering unit relative to the vehicle frame of the heavy-duty vehicle.

3. The heavy-duty vehicle of claim 2, wherein the steering input element comprises a steering actuator that is rotatable around an axis of rotation stationary to the vehicle frame of the heavy-duty vehicle, wherein the steering actuator is arranged at a substantially unchangeable distance from the axis of rotation stationary to the vehicle frame, wherein the steering actuator defines a pivot axis for the coupling unit connected to the steering actuator.

4. The heavy-duty vehicle of claim 3, further comprising a steering plate rotatable relative to the vehicle frame of the heavy-duty vehicle about the axis of rotation stationary to the vehicle frame dependent upon a steering angle of the heavy-duty vehicle, wherein the steering actuator is connected to the steering plate eccentrically to the axis of rotation stationary to the vehicle frame.

5. The heavy-duty vehicle of claim 1, wherein the steering unit comprises a variable in length actuating unit, and further comprising a further steering device, wherein the steering unit is connected both to the steering device and to the further steering device, wherein the at least one actuating unit of the steering unit is configured to displace at least one connecting portion associated with the steering device relative to the axis of rotation of the steering unit.

6. The heavy-duty vehicle of claim 5, wherein the steering unit further comprises a further actuating unit configured to displace at least one connecting portion associated with the further steering device relative to the axis of rotation of the steering unit.

7. The heavy-duty vehicle of claim 6, wherein the at least one actuating unit of the steering unit is configured to displace a pair of connecting portions synchronously relative to the axis of rotation of the steering unit.

8. The heavy-duty vehicle of claim 1, wherein a direction of change in length of at least one of the at least one actuating unit of the steering unit is oriented orthogonally to the axis of rotation of the steering unit.

9. The heavy-duty vehicle of claim 1, wherein the at least one actuating unit is configured as a hydraulic cylinder, a double cylinder, a spindle drive, double spindle drive, a rack drive, a linear unit, or a sliding block unit.

10. The heavy-duty vehicle of claim 4, wherein the steering plate comprises a kingpin and a steering wedge, wherein the kingpin and the steering wedge are configured to engage non-rotatably with a higher-level assembly that is not part of the heavy-duty vehicle.

11. The heavy-duty vehicle of claim 4, wherein a direction of rotation of the steering plate relative to the vehicle frame of the heavy-duty vehicle about the axis of rotation of the steering plate is the same as a resulting direction of rotation of the steering unit about the axis of rotation of the steering unit.

12. The heavy-duty vehicle of claim 4, wherein the at least one actuating unit of the steering unit is arranged outside the steering plate in a direction orthogonal to the axis of rotation of the steering plate.

13. The heavy-duty vehicle of claim 1, wherein the steering device to which the steering unit is connected comprises a hydraulic circuit, wherein the at least one connecting portion associated with the steering device is connected to a piston-cylinder arrangement, wherein the piston-cylinder arrangement is arranged so that a rotation of the steering unit about the axis of rotation of the steering unit causes a relative displacement of piston and cylinder in the piston-cylinder arrangement to actuate a hydraulic circuit of the steering device.

14. The heavy-duty vehicle of claim 4, wherein two piston-cylinder arrangements are associated with each of the steering device and a further steering device, wherein one of the two piston-cylinder arrangements is connected, in each case, to the steering unit at one of connecting portions arranged on two sides of a central plane which extends through the axis of rotation of the steering unit.

15. The heavy-duty vehicle of claim 14, wherein respective ends of the two piston-cylinder arrangements opposite the steering unit are rotatably mounted on a same side of the plane about a common axis substantially parallel to the axis of rotation of the steering unit.

16. The heavy-duty vehicle of claim 1, wherein the at least one actuating unit is variable in length.

17. The heavy-duty vehicle of claim 5, wherein the at least one connecting portion comprises multiple connection portions, and wherein the at least one actuating unit of the steering unit is configured to displace all of the multiple connecting portions relative to the axis of rotation of the steering unit.

18. The heavy-duty vehicle of claim 6, wherein the further actuating unit is variable in length.

19. The heavy-duty vehicle of claim 6, wherein the at least one connecting portion comprises multiple connection portions, and wherein the further actuating unit is configured to displace all of the multiple connection portions relative to the axis of rotation of the steering unit.

20. The heavy-duty vehicle of claim 10, wherein the higher-level assembly comprises a tractor unit and wherein the axis of rotation stationary to the vehicle frame is substantially coaxial with a central axis of the kingpin.

21. The heavy-duty vehicle of claim 14, wherein the one of the two piston-cylinder arrangements is connected, in each case, to the steering unit at one of connecting portions arranged symmetrically on the two sides of the central plane which extends through the axis of rotation of the steering unit.

Description

[0035] In the following, the present invention will be explained in more detail using an exemplary embodiment making reference to the accompanying drawings. In the drawings:

[0036] FIG. 1 shows a schematic structure of a heavy-duty vehicle according to the invention;

[0037] FIG. 2 shows a detail of the embodiment of the heavy-duty vehicle according to the invention as per FIG. 1 in a perspective view;

[0038] FIG. 3 shows the detail of FIG. 2 in a further perspective view;

[0039] FIG. 4 shows a further embodiment of the detail of FIG. 2;

[0040] FIG. 5 shows a portion, in particular a rear portion, of the heavy-duty vehicle according to the invention;

[0041] FIG. 6 shows a further embodiment of a portion, in particular of a rear section, of the heavy-duty vehicle according to the invention.

[0042] In FIG. 1, a heavy-duty vehicle according to the invention is identified, in general, by the reference sign 10. The heavy-duty vehicle 10 is configured here as a semi-trailer which is connected to a tractor unit 12, which does not form part of the invention. The tractor unit 12 is rotated relative to the semi-trailer 10 about an axis of rotation A, on which the tractor unit 12 is connected to the semi-trailer 10, by an angle α.

[0043] FIG. 2 shows, in a detail view, how a steering of the tractor unit 12 is transferred to the semi-trailer 10.

[0044] In the exemplary embodiment shown here, the semi-trailer 10 comprises a steering plate 14 which is mounted on the semi-trailer 10 so as to be rotatable about the axis of rotation A. The steering plate 14 is non-rotatably connected to the tractor unit 12.

[0045] A steering input element 16 is arranged on the steering plate 14. The steering input element 16, which is designed here as a steering actuator 16, is arranged at a fixed distance from the axis of rotation A. A coupling unit 18, which is designed here as a coupling rod 18, is arranged on the steering input element 16 and pivotable about it, about a pivot axis B. At the end of the coupling unit 18 opposite the steering input element 16, the coupling unit is also pivotably connected to a steering unit 20.

[0046] The steering unit 20 is connected in a stationary manner to the heavy-duty vehicle 10 or its vehicle frame, but rotatable about an axis of rotation C (see FIG. 3). This means that a distance between the axis of rotation A and the axis of rotation C cannot be changed.

[0047] Upon rotation of the steering plate 14 about the axis of rotation A, the coupling unit 18 is displaced together with the steering actuator 16, as a result of which the steering unit 20 is set in rotation about the axis of rotation C.

[0048] At its outer ends, the steering unit 20 has connecting portions 22, at which the steering unit 20 is connected in an articulated manner to piston-cylinder arrangements 24, 26, 28 and 30. The piston-cylinder arrangements 24, 26, 28 and 30 are connected to the heavy-duty vehicle 10 at their ends opposite the steering unit 20 about a particular common pivot axis D or D′. A rotation of the steering unit 20 about the axis of rotation C thus causes the piston-cylinder arrangements 24 and 28 arranged on one side of the steering unit 20 to be extended, for example, that is to say the piston rods connected to the connecting portions 22 are displaced from their respective cylinders whereas the piston-cylinder arrangements 26 and 30 are retracted. In the exemplary embodiment shown, the piston-cylinder arrangements are designed as double-acting hydraulic cylinders.

[0049] The steering unit 20 here comprises a variable in length actuating unit 32 which is configured to move the connecting portions 22 connected to it away from or towards the axis of rotation C, i.e. to change a particular distance between the connecting portions 22 connected to the variable in length actuating unit 32 and the axis of rotation C.

[0050] Depending on the set distance between the connecting portions 22 and the axis of rotation C, the leverage of the steering unit 20 to the piston-cylinder arrangements 24 to 30 changes. In other words, the distance between the connecting portions 22 and the axis of rotation C can be used to set a ratio of the distance by which a piston of a particular piston-cylinder arrangement is displaced at a specific angle of rotation of the steering unit 20. Since a change in the amount of fluid that is present in a corresponding chamber of a particular piston-cylinder arrangement 24 to 30 causes a proportional actuation of an associated steering device, a transmission ratio of the angle α between the tractor unit 12 and the semi-trailer 10 can be adjusted via the above-mentioned ratio to an extent of an actuation of the steering device associated with the variable in length actuating unit 32.

[0051] In the embodiment shown in FIG. 2, the piston-cylinder arrangements 24 and 26 are associated with a first steering device of the heavy-duty vehicle 10 and the piston-cylinder arrangements 28 and 30 are associated with a second steering device of the heavy-duty vehicle 10, and furthermore, in the embodiment shown in FIG. 2, a variable in length actuating unit 32 is associated only with the first steering device, so that only the first steering device of the heavy-duty vehicle 10 comprises a steering device with an adjustable transmission ratio.

[0052] The arrangement of two piston-cylinder arrangements 24, 26 or 28, 30, respectively, each for a single steering device is due here to corresponding regulations, which are to be complied with, for example, in the context of German road traffic. Naturally, the same effect could also be achieved using only the piston-cylinder arrangements 24 and 28 or 26 and 30 (or 24 and 30 or 26 and 28).

[0053] In FIG. 3, the arrangement of FIG. 2 is shown in a perspective view from below. It can be seen here that the steering plate 14 has a kingpin 34 on its underside, centred on the axis of rotation A, and a steering wedge 36 that is firmly connected to the underside of the steering plate 14. By engaging the kingpin 34 and the steering wedge 36 with, for example, a semi-trailer coupling (not shown), the steering plate 14 can be non-rotatably connected to this semi-trailer coupling.

[0054] Furthermore, a pin 38 can be seen in FIG. 3, which is connectable to a vehicle frame of the heavy-duty vehicle 10 via a screw connection on the lower side shown in FIG. 3, and which defines the axis of rotation C about which the steering unit 20 can rotate.

[0055] An alternative or additional arrangement of a connecting portion 22 is shown in FIG. 4. In the embodiment shown in FIG. 4, although the actuating units 32 of the embodiment according to FIGS. 2 and 3 are still shown here, the connecting portion 22 on which the steering input element 16 and/or the coupling unit 18 which is connected to the steering input element 16 can be displaced relative to the axis of rotation C of the steering unit 20 in such a way that a transmission ratio of a rotation of the steering plate 14 about the axis of rotation A to a rotation of the steering unit 20 about the axis of rotation C is changed.

[0056] FIG. 5 shows a portion, in particular a rear portion, of a heavy-duty vehicle 10 according to the invention, with two piston-cylinder arrangements 40 serving as steering input elements 16 here to exert a force on the steering unit 20 in order to rotate the steering unit 20 about the axis of rotation C. The two piston-cylinder arrangements 40 are provided here in a redundant manner and it is also conceivable to provide only one piston-cylinder arrangement 40.

[0057] The steering unit 20 is connected in FIG. 5 via a connecting rod 42 to a pivot lever 44 which is mounted on the vehicle frame of the heavy-duty vehicle 10 about an axis of rotation E. Two steering rods 46 are in turn connected to the pivot lever 44, each of which is coupled to a turntable 48 of a particular wheel assembly comprising at least one wheel (not shown) such that a displacement of a steering rod 46, in particular substantially in the vehicle width direction, causes a rotation of the wheel assembly relative to the vehicle frame of the heavy-duty vehicle 10. The term “turntable” can be applied equally to a turntable of a full floating axle and to a steering arm of a steering arm axis.

[0058] In order to implement the basic inventive concept of setting a transmission ratio between a force or displacement path input by a particular steering input element 16 and a force or displacement path, respectively, output to a particular wheel assembly, a variable in length actuating unit 32 can be arranged on a connecting portion 22 between the steering input element 16, i.e. in FIG. 5 at least one of the piston-cylinder arrangements 40, and the steering unit 20 and/or a connecting portion 22 between the steering unit 20 and a bearing about the axis of rotation C and/or a connecting portion 22 between the steering unit 20 and the connecting rod 42 and/or a connecting portion 22 between the connecting rod 42 and the pivot lever 44 and/or a connecting portion 22 between the pivot lever 44 and a bearing about the axis of rotation E and/or a connecting portion 22 between the pivot lever 44 and a steering rod 46 and/or a connecting portion 22 between a steering rod 46 and the wheel assembly or the turntable 48, respectively, or an element connected thereto.

[0059] In the embodiment of the heavy goods vehicle 10 shown in FIG. 6, the steering unit 20 is arranged offset from a centre in the vehicle width direction of the heavy-duty vehicle 10. With regard to the features and mode of operation as well as the possible arrangements of a connecting portion 22 of the embodiment shown in FIG. 6, reference is made at this point to the embodiments described above. In the embodiment of FIG. 6, the steering input element 16 is also configured as a piston-cylinder arrangement 40.