Rail Vehicle Having a Carriage Coupling Device

Abstract

A rail vehicle having at least a first carriage and a second carriage intercoupled via a carriage coupling device that has a variable resistance to twisting of the at least first carriage relative to the second carriage, wherein a first resistance torque gradient of the carriage coupling device at a first angular position of the at least first carriage relative to the second carriage in a direction of rotation is greater in magnitude than a second resistance torque gradient of the carriage coupling device at a second angular position of the at least first carriage relative to the second carriage in the same direction of rotation, where the first angular position is associated with a lesser twisting of the at least first carriage relative to the second carriage than the second angular position, such that an improved driving behavior of the rail vehicle is achieved, particular when entering track curves.

Claims

1-15. (canceled)

16. A rail vehicle comprising: at least one first carriage; carriage articulation device; and a second carriage coupled to the first carriage via the carriage articulation device; wherein the carriage articulation device has a variable resistance to twisting of the at one least first carriage relative to the second carriage; wherein a first resistance torque gradient of the carriage articulation device is greater in magnitude in cases of a first angular position of the at least first carriage relative to the second carriage in one direction of rotation than a second resistance torque gradient of the carriage articulation device in cases of a second angular position of the at least first carriage relative to the second carriage in the same direction of rotation; and wherein the first angular position is associated with a lesser twisting of the at least first carriage relative to the second carriage than the second angular position.

17. The rail vehicle as claimed in claim 16, wherein a first resistance torque of the carriage articulation device in cases of the first angular position has greater magnitude than a second resistance torque of the carriage articulation device in cases of a third angular position of the at least first carriage relative to the second carriage in the same direction of rotation; and wherein the first angular position is associated with a lesser twisting of the at least first carriage relative to the second carriage than the third angular position.

18. The rail vehicle as claimed in claim 17, wherein the carriage articulation device has a maximum third resistance torque in terms of magnitude in cases of a fourth angular position of the at least first carriage relative to the second carriage between the first angular position and the third angular position in the same direction of rotation.

19. The rail vehicle as claimed in claim 16, wherein the carriage articulation device includes a pivot point and includes a first spring which is connected to the at least one first carriage and the second carriage, a first normal distance between a first spring longitudinal axis of the first spring and the pivot point being variable; and wherein the carriage articulation device further includes a second spring which is connected to the at least first carriage and the second carriage, a second normal distance between a second spring longitudinal axis of the second spring and the pivot point being variable.

20. The rail vehicle as claimed in claim 19, wherein the first and second springs are pretensioned.

21. The rail vehicle as claimed in claim 19, wherein the first and second springs are formed as compression springs.

22. The rail vehicle as claimed in claim 20, wherein the first and second springs are formed as compression springs.

23. The rail vehicle as claimed in claim 19, wherein the first and second springs are connected in an articulated manner to the at least one first carriage and the second carriage.

24. The rail vehicle as claimed in claim 20, wherein the first and second springs are connected in an articulated manner to the at least one first carriage and the second carriage.

25. The rail vehicle as claimed in claim 21, wherein the first and second springs are connected in an articulated manner to the at least one first carriage and the second carriage.

26. The rail vehicle as claimed in claim 19, wherein the first spring is combined with a first damper to form a first spring/damper unit and the second spring is combined with a second damper to form a second spring/damper unit.

27. The rail vehicle as claimed in claim 19, wherein the first normal distance in the first angular position is greater than the second normal distance in the second angular position.

28. The rail vehicle as claimed claim 16, wherein the carriage articulation device includes a curved molding which is bent multiple times in opposite directions, a first guide arm, a first roller which is connected rotatably to the first guide arm, and a second guide arm and a second roller which is connected rotatably to the second guide arm; wherein the first guide arm and the second guide arm are coupled to the at least first carriage in an articulated manner; wherein the curved molding is coupled to the second carriage; and wherein the first and second rollers and the curved molding are intercoupled via rolling contacts.

29. The rail vehicle as claimed in claim 28, wherein the curved molding has an undulating first mold contour which contacts the first roller and an undulating second mold contour which contacts the second roller.

30. The rail vehicle as claimed in claim 29, wherein the first roller contacts a first wave trough of the first mold contour and the second roller contacts a second wave trough of the second mold contour if the at least first carriage has a neutral angular position of 0 relative to the second carriage.

31. The rail vehicle as claimed in claim 28 wherein the curved molding is coupled to the second carriage immovably relative to the second carriage.

32. The rail vehicle as claimed in claim 29, wherein the curved molding is coupled to the second carriage immovably relative to the second carriage.

33. The rail vehicle as claimed in claim 30, wherein the curved molding is coupled to the second carriage immovably relative to the second carriage.

34. The rail vehicle as claimed in claim 16, wherein the carriage articulation device has a carriage articulation.

35. The rail vehicle as claimed in claim 16, wherein the twisting of the at least first carriage relative to the second carriage is substantially a rotation in relation to a parallel of a vehicle vertical axis.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention is explained in greater detail below on the basis of exemplary embodiments, in which:

[0023] FIG. 1 shows a schematic outline of a cut-out from an exemplary first embodiment of a rail vehicle in accordance with the invention having a first carriage and a second carriage, the carriage articulation device of which comprises a carriage articulation, a first spring and a second spring;

[0024] FIG. 2 shows an exemplary embodiment of a diagram that represents a graphical plot of profile of a resistance torque of a carriage articulation device above an angular position between two carriages of a rail vehicle;

[0025] FIG. 3: shows a schematic outline of a cut-out from an exemplary second embodiment of a rail vehicle in accordance with the invention having a first carriage and a second carriage, the carriage articulation device of which comprises a carriage articulation, a first spring/damper unit and a second spring/damper unit; and

[0026] FIG. 4: shows a schematic outline of a cut-out from an exemplary third embodiment of a rail vehicle in accordance with the invention having a first carriage and a second carriage, the carriage articulation device of which comprises a carriage articulation, a curved molding, a first guide arm with a first roller as well as a second guide arm with a second roller.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0027] FIG. 1 shows a schematic outline of a cut-out of an exemplary first embodiment of a rail vehicle having a first carriage 1 and a second carriage 2 in accordance with the invention.

[0028] The rail vehicle is formed as a low floor tram. The first carriage 1 has a first idler chassis 3, and the second carriage 2 has a second idler chassis 4. The rail vehicle comprises further chassis and further carriages which are, however, not represented in FIG. 1.

[0029] The first carriage 1 and the second carriage 2 are coupled to one another via a carriage articulation device 5, where the carriage articulation device 5 has a variable resistance against twisting of the first carriage 1 relative to the second carriage 2. This twisting occurs substantially in relation to a parallel to a vehicle vertical axis 42 of the rail vehicle that appears in a projecting manner in FIG. 1. This parallel acts as an axis of rotation and can move or change in the course of the rotation.

[0030] The carriage articulation device 5 comprises a carriage articulation 6, in the center of which a pivot point 7 of the carriage articulation device 5 is arranged, and comprises a first spring 8 and a second spring 9. The first spring 8 and the second spring 9 are connected to the first carriage 1 and the second carriage 2 in an articulated or rotatable manner and are formed as pretensioned, metallic screw/compression springs.

[0031] A first spring longitudinal axis 10 of the first spring 8 and a second spring longitudinal axis 11 of the first spring 9 are, in a relative neutral angular position 12 of 0 between the first carriage 1 and the second carriage 2, as is represented in FIG. 1, oriented obliquely in relation to a vehicle longitudinal axis 13. A first normal distance 14 is provided between the first spring longitudinal axis 10 and the pivot point 7, and a second normal distance 15 is provided between the second spring longitudinal axis 11 and the pivot point 7.

[0032] If the first carriage 1 travels into a track curve, then an angular position between the first carriage 1 and the second carriage 2 is increased firstly from the neutral angular position 12 because the second carriage 2 is still traveling along a straight section of track. When the first carriage 1 is entering the track curve, a first angular position 16 is gradually reached between the first carriage 1 and the second carriage 2 and later, via a second angular position 17 shown in FIG. 2, a third angular position 18 is gradually reached between the first carriage 1 and the second carriage 2, in the same direction of rotation about the pivot point 7 as the first angular position 16. A twisting of the first carriage 1 relative to the second carriage 2 therefore occurs.

[0033] A first spring force of the first spring 8 and a second spring force of the second spring 9 change during twisting between the neutral angular position 12, the first angular position 16, the second angular position 17 and the third angular position 18, because the first spring 8 and the second spring 9 are compressed or expanded during twisting as a result of their connections to the first carriage 1 and to the second carriage 2.

[0034] The first normal distance 14 and the second normal distance 15 change during twisting because the first spring longitudinal axis 10 and the second spring longitudinal axis 11 change their orientation during twisting.

[0035] A resistance torque of the carriage articulation device 5 is changed via the first spring 8 and the first normal distance 14 and via the second spring 9 and the second normal distance 15.

[0036] During the described twisting, the first spring 8 is compressed and the first spring force is increased, as a result of which the resistance torque between the neutral angular position 12 and the first angular position 16 is increased. At the same time, the first normal distance 14, however, is reduced during twisting. In the case of twisting beyond the first angular position 16, the reducing first normal distance 14 influences the resistance torque to a greater extent than the first spring force which reaches a spring force maximum during twisting.

[0037] As a result of this, the resistance torque reduces in terms of magnitude once a resistance torque maximum is reached, which resistance torque maximum is arranged between the first angular position 16 and the third angular position 18.

[0038] The second spring force initially decreases during the stated twisting and rotates from a relaxed spring position about 180, and therefore transforms from a compressive force into a tensile force. The second normal distance 15 does indeed increase during the stated twisting, but this, as a result of the second spring force that initially reduces during twisting and is later rotated about 180, only insignificantly influences the resistance torque or not in an undesirable manner. As a result, the resistance torque does not change in its initially increasing and, once the resistance torque maximum is reached, decreasing tendency.

[0039] FIG. 2 discloses an exemplary embodiment of a diagram that represents a graphical plot of a resistance torque of a carriage articulation device 5 of a rail vehicle, as is shown by way of example in FIG. 1, over an angular position between a first carriage 1 and a second carriage 2 of the rail vehicle. This profile is achieved by arranging a first spring 8 and a second spring 9 between the first carriage 1 and the second carriage 2 in a manner as represented in FIG. 1.

[0040] The graphical plot has an x-axis 20 on which the angular position is plotted as well as a y-axis 21 on which the resistance torque is plotted. The profile of the resistance torque is non-linear.

[0041] In a neutral angular position 12 of 0, the resistance torque is not equal to zero because a carriage articulation 6 of the carriage articulation device 5 has a base rotational resistance.

[0042] In the case of a first angular position 16 between the first carriage 1 and the second carriage 2 in a direction of rotation that is greater than the neutral angular position 12, the carriage articulation device 5 has a first resistance torque 22 against a twisting of the first carriage 1 relative to the second carriage 2 that is greater than the resistance torque in the neutral angular position 12. In the first angular position 16, the carriage articulation device 5 furthermore has a first resistance torque gradient 25.

[0043] In the case of a second angular position 17 between the first carriage 1 and the second carriage 2 in the same direction of rotation, the carriage articulation device 5 has a second resistance torque gradient 26. The first resistance torque gradient 25 is greater in terms of magnitude than the second resistance torque gradient 26. An increase in the resistance torque therefore reduces, where the profile of the resistance torque becomes flatter.

[0044] In the case of a third angular position 18 between the first carriage 1 and the second carriage 2 in the same direction of rotation, the carriage articulation device 5 has a second resistance torque 23 against the twisting of the first carriage 1 relative to the second carriage 2.

[0045] In the third angular position 18, the first carriage 1 is twisted to a greater extent relative to the second carriage 2 than in the first angular position 16. The first resistance torque 22 is greater in terms of magnitude than the second resistance torque 23.

[0046] The carriage articulation device 5 furthermore has, in the case of a fourth angular position 19 between the first angular position 16 and the third angular position 18, a maximum third torque resistance 24 in terms of magnitude. The resistance torque therefore increases in terms of magnitude from the resistance torque in the neutral angular position 12 via the first resistance torque 22 in the first angular position 16 up to the maximum third resistance torque 24 and then reduces in terms of magnitude in the case of a further increase in the angular position between the first carriage 1 and the second carriage 2 in the same direction of rotation via the second resistance torque 23 in the third angular position 18.

[0047] The profile of the resistance torque between the first resistance torque 22 and the second resistance torque 23 is influenced because a first normal distance 14 described by way of example in conjunction with FIG. 1 between a first spring longitudinal axis 10 of the first spring 8 and a pivot point 7 of the carriage articulation device 5 in the first angular position 16 is greater than in the second angular position 17 and in the third angular position 18.

[0048] In accordance with the invention, it is also conceivable to allow the resistance torque to increase in terms of magnitude only to such an extent that the second resistance torque gradient 26 is reached because a reduction in the resistance torque gradient already delivers improvements in terms of driving dynamics when the rail vehicle enters track curves.

[0049] FIG. 3 shows a schematic outline of a cut-out of an exemplary second embodiment of a rail vehicle in accordance with the invention having a first carriage 1 and a second carriage 2 that are coupled to a carriage articulation 6 via a carriage articulation device 5.

[0050] This exemplary second embodiment is structurally and functionally similar to that exemplary first embodiment of a rail vehicle in accordance with the invention that is represented in FIG. 1. Partially identical reference signs are therefore used in FIG. 3 as in FIG. 1.

[0051] In contrast to FIG. 1, the carriage articulation device 5 of FIG. 3 has a first spring/damper unit and a second spring/damper unit that are arranged between the first carriage 1 and the second carriage 2 and connected to the first carriage 1 and to the second carriage 2 in an articulated manner.

[0052] A first spring 8 and a first damper 27 are combined to form the first spring/damper unit, and a second spring 9 and a second damper 28 are combined to form the second spring/damper unit. The first spring 8 and the second spring 9 are formed as pressure-pretensioned helical springs, where the first spring 8 sheathes the first damper 27 and the second spring 9 sheathes the second damper 28. The first damper 27 and the second damper 28 are formed as hydraulic telescopic dampers.

[0053] A first spring longitudinal axis 10 of the first spring/damper unit and a second spring longitudinal axis 11 of the second spring/damper unit are oriented in that neutral angular position 12 shown in FIG. 3 of 0 between the first carriage 1 and the second carriage 2 obliquely to a vehicle longitudinal axis 13.

[0054] FIG. 4 represents a schematic outline of a cut-out of an exemplary third embodiment of a rail vehicle in accordance with the invention having a first carriage 1 and a second carriage 2 that are connected to one another via a carriage articulation device 5 with a carriage articulation 6.

[0055] The first carriage 1 has a first idler chassis 3, the second carriage 2 has a second idler chassis 4. The rail vehicle comprises further carriages and further idler chassis, which are, however, not shown in FIG. 4.

[0056] The carriage articulation device 5 furthermore has a curved molding 29 that is bent multiple times in opposite directions, a first guide arm 30, a first roller 32 that is connected rotatably to the first guide arm 30, a second guide arm 31 and a second roller 33 that is connected rotatably to the second guide arm 31. The first guide arm 30 and the second guide arm 31 are coupled to the first carriage 1 in an articulated manner. The curved molding 29 is connected to the second carriage 2, immovably relative to the second carriage 2.

[0057] The first roller 32 and the second roller 33 are coupled to the curved molding 29 via rolling contacts, i.e., can roll on the curved molding 29. The curved molding 29 has an undulating first mold contour 34 which contacts the first roller 32 and an undulating second mold contour 35 that contacts the second roller 33.

[0058] In a neutral angular position 12 of 0 between the first carriage 1 and the second carriage 2, as shown in FIG. 4, the curved molding 29 is symmetrical in relation to a vehicle longitudinal axis 13 of the rail vehicle. In this neutral angular position 12 and in relation to that image view of FIG. 4, the first guide arm 30 with the first roller 32 and the first mold contour 34 are arranged above the vehicle longitudinal axis 13 and the second guide arm 31 with the second roller 33 and the second mold contour 35 are arranged below the vehicle longitudinal axis 13.

[0059] In the described neutral angular position 12, the first roller 32 contacts a first wave trough 36 of the first mold contour 34 and the second roller 33 contacts a second wave trough 37 of the second mold contour 35.

[0060] If the first carriage 1 deflects during a twisting relative to the second carriage 2 from the neutral angular position 12 in the direction of rotation of a first angular position 16, then the first roller 32 moves out of the first wave trough 36 to a first wave peak 38 of the first mold contour 34 and the second roller 33 moves from the second wave trough 37 to a second wave peak 39 of the second mold contour 35.

[0061] Contact forces between the first roller 32 and the first mold contour 34 and between the second roller 33 and the second mold contour 35 increase in magnitude.

[0062] A resistance torque of the carriage articulation device 5, formed from the contact forces and from variable normal distances between the contact forces and a pivot point 7 of the carriage articulation device 5 increases as a result, where a resistance torque gradient between the first angular position 16 and a second angular position 17 as a result of a decreasing pitch between wave troughs and wave peaks of the curved molding 29 decreases in terms of magnitude.

[0063] If the first carriage 1 further twists relative to the second carriage 2 in the same direction of rotation, i.e. in the direction of a third angular position 18, then the first roller 32 rolls from the first wave peak 38 and the second roller 33 rolls from the second wave peak 39. As a result of this, the contact forces and the resistance torque are reduced.

[0064] A profile of the resistance torque as a function of an angular position, proceeding from the neutral angular position 12 in the direction of the first angular position 16, of the second angular position 17 and the third angular position 18, is similar to that profile which is represented in FIG. 2.

[0065] A pressure-pretensioned first contact pressure spring 40 is arranged between the first carriage 1 and the first guide arm 30, and a pressure-pretensioned second contact pressure spring 41 is arranged between the first carriage 1 and the second guide arm 31. The first contact pressure spring 40 pushes the first roller 32 against the first mold contour 34, the second contact pressure spring 41 the second roller 33 against the second mold contour 35. In accordance with the invention, it is also conceivable that the first roller 32 and the second roller 33 are connected via a brace and are thus pushed against the first mold contour 34 or the second mold contour 35.

[0066] In accordance with the invention, it is furthermore conceivable that the first guide arm 30 and the second guide arm 31 themselves have contact pressure structures, for example, torsion springs in articulations of the first guide arm 30 and of the second guide arm 31.

[0067] Thus, while there have been shown, described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements that perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.