COUPLING DEVICE FOR COUPLING A TOWING VEHICLE TO A TRAILER

Abstract

A device for coupling a towing vehicle to a trailer vehicle of a vehicle combination, where the towing vehicle has a trailer coupling and the trailer vehicle has a drawbar. A measurement device is configured to measure forces and/or torques between the towing vehicle and the trailer vehicle has a two-part support with a first and second support components. The first support component has at least two measurement arms which extend radially and are symmetrically offset relative to one another. A strain gauge rosette is on each measurement arm. The second support component has counter-arms which extend radially and which correspond in number and arrangement to the measurement arms. The two support components can be attached firmly to one another and to the trailer coupling or to the drawbar. Also disclosed is a measurement-data capture and evaluation unit.

Claims

1-9. (canceled)

10. A coupling device (1) for coupling a towing vehicle (4) to a trailer vehicle (5) of a vehicle combination, in which the towing vehicle (4) comprises a trailer coupling (3) and the trailer vehicle (5) comprises a drawbar (6) that can be coupled to the trailer coupling (3), and with a measurement device (2) for measuring forces and/or torques between the towing vehicle (4) and the trailer vehicle (5), wherein: the measuring device (2) comprises a two-part support (7.1, 7.2, 7.3, 7.4) having an elongated first support component (8.1, 8.2, 8.3, 8.4) in the form of a sensor carrier and having, as a counterpart of the first support component (8.1, 8.2, 8.3, 8.4), an elongated second support component (9.1, 9.2, 9.3, 9.4), the first support component (8.1, 8.2, 8.3, 8.4) comprising at least two measurement arms (13a, 13b; 30a, 30b, 30c; 32a, 32b, 32c, 32d; 35a, 35b, 35c, 35d, 35e, 35f) which extend radially at a first end of the first support component (8.1, 8.2, 8.3, 8.4); the measurement arms (13a, 13b, 30a-30c, 32a-32d, 35a-35f) of the first support component (8.1, 8.2, 8.3, 8.4) are arranged symmetrically relative to one another; on each measurement arm (13a, 13b, 30a-30c, 32a-32d, 35a-35f) of the first support component (8.1, 8.2, 8.3, 8.4) there is arranged a strain gauge rosette (23, 23a, 23b, 23c, 24) that acts as a force sensor; the second support component (9.1, 9.2, 9.3, 9.4) has counter-arms (20a, 20b; 31a, 31b, 31c; 33a, 33b, 33c, 33d; 35a, 35b, 35c, 35d, 35e, 35f) which extend radially at a first end of the second support component (9.1, 9.2, 9.3, 9.4) and which correspond in number and arrangement to the measurement arms (13a, 13b, 30a-30c, 32a-32d, 35a-35f) of the first support component (8.1, 8.2, 8.3, 8.4); each of the first support components (8.1, 8.2, 8.3, 8.4) and the second support components (9.1, 9.2, 9.3, 9.4) has a first end, wherein the first end of each of the first support components faces a first end of a respective second support component, and facing first ends are configured to be connected by connecting the measurement arms (13a, 13b, 30a-30c, 32a-32d, 35a-35f) of the first support component (8.1, 8.2, 8.3, 8.4) with the respective associated counter-arms (20a, 20b; 31a-31c; 33a-33d; 35a-35f); the first end of the first support component (8.1, 8.2, 8.3, 8.4) facing toward the towing vehicle (4) can be connected firmly to the coupling means (6a) on the trailer side; the first end of the second support component (9.1, 9.2, 9.3, 9.4) facing toward the trailer vehicle (5) can be connected firmly to the drawbar (6); and the measurement device (2) comprises: a measurement-data capture and evaluation unit (26) configured to be electrically connected to the strain gauge rosettes (23, 23a, 23b, 23c, 24), the measurement device (2) arranged completely or in part on the two-part support (7.1, 7.2, 7.3, 7.4) or remotely therefrom, the measurement device (2) configured to detect and evaluate deformations of the coupling device (1) caused by forces and/or bending moments in three axial directions and that are correlated with electric signals; an electronic circuit and/or a computer program with an algorithm by means of which, from the sensor signals captured, the coupling forces, coupling bending moments and/or components thereof acting upon the coupling device (1) can be determined according to size and direction and in sequence of time, and can be made available for further processing.

11. The coupling device according to claim 10, comprising: a strain gauge rosette (23, 24) on a free end of each measurement arm (13a, 13b, 30a-30c, 32a-32d, 35a-35f), the strain gauge rosette (23, 24) consisting of three strain gauges (23a, 23b, 23c); a central strain gauge (23b) orientated on each measurement arm in a direction of a notional longitudinal axis of the measurement arm (13a, 13b, 30a-30c, 32a-32d, 35a-35f); and two strain gauges (23a, 23c) adjacent to the central strain gauge (23b) and arranged alongside the central strain gauge and at an angle from 0° and 90° relative to the central strain gauge.

12. The coupling device of claim 11, wherein the angle is from 45° to 60°.

13. The coupling device according to claim 10, wherein: the two-part support (7.1) is in the form of a two-arm arrangement; the first support component (8.1) comprises a radially extending first measurement arm (13a) and a radially extending second measurement arm (13b) orientated diametrically opposite the first measurement arm; and the second support component (9.1) has two correspondingly designed and arranged counter-arms (20a, 20b).

14. The coupling device according to claim 10, wherein the two-part support (7.2) is in the form of a three-arm arrangement; the first support component (8.2) comprises three radially extending measurement arms (30a, 30b, 30c) with adjacent measurement arms (30a, 30b, 30c) are offset by an angle of 120°; and the second support component (9.2) has three correspondingly configured and arranged counter-arms (31a, 31b, 31c).

15. The coupling device according to claim 10, wherein: the two-part support (7.3) is in the form of a four-arm arrangement; the first support component (8.3) has four radially extending measurement arms (32a, 32b, 32c, 32d with adjacent measurement arms offset by an angle of 90°; and the second support component (9.3) has four correspondingly configured and arranged counter-arms (33a, 33b, 33c, 33d).

16. The coupling device according to claim 10, wherein: the two-part support (7.4) is in the form of a six-arm arrangement; the first support component (8.4) has six radially extending measurement arms (35a, 35b, 35c, 35d, 35e, 35f) with adjacent measurement arms offset by an angle of 60°; and the second support component (9.4) has six correspondingly configured and arranged counter-arms (36a, 36b, 36c, 36d, 36e, 36f).

17. The coupling device according to claim 10, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

18. The coupling device according to claim 11, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

19. The coupling device according to claim 12, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

20. The coupling device according to claim 13, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

21. The coupling device according to claim 14, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

22. The coupling device according to claim 15, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

23. The coupling device according to claim 16, further comprising one or more strain gauge rosettes (23, 23a, 23b, 23c, 24) arranged on one or more of the counter-arms (20a, 20b; 31a-31c; 33a-33d; 36a-36f) of the second support component (9.1, 9.2, 9.3, 9.4).

24. A measurement device (2) for measuring forces and/or torques between a towing vehicle (4) and a trailer vehicle (5) of a vehicle combination, comprising the coupling according to claim 10.

25. A vehicle combination comprising the coupling device (1) for coupling the towing vehicle (4) to the trailer vehicle (5), and with a measurement device for measuring forces and/or torques, wherein the coupling device (1) according to claim 10.

26. The vehicle combination of claim 25, comprising a passenger car caravan.

27. The vehicle combination of claim 25, comprising a pick-up-drawbar-trailer train.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Below, the invention will be explained in greater detail with reference to a number of example embodiments illustrated in the attached drawings, which show:

[0042] FIG. 1: A schematic view of a coupling device with a measurement device having the features of the invention, and with a first embodiment of a two-part support, viewed from the side,

[0043] FIG. 2: A perspective view of the two-part support shown in FIG. 1,

[0044] FIG. 3: A perspective view of a first support component of the two-part support, with two measurement arms as in FIGS. 1 and 2,

[0045] FIG. 4: A detailed view of a measurement arm of the first support component of the two-part support of the coupling device, with a strain gauge rosette,

[0046] FIG. 5: A detailed view of the strain gauge rosette shown in FIG. 4,

[0047] FIG. 6: A perspective view of a two-part support with three measurement arms, according to a second embodiment of the invention,

[0048] FIG. 7: A view from above, of the support with the three measurement arms as shown in FIG. 6,

[0049] FIG. 8: A side view of the support with the three measurement arms as shown in FIG. 6,

[0050] FIG. 9: A perspective view of a two-part support with four measurement arms according to a third embodiment of the invention,

[0051] FIG. 10: A perspective view of the first support component of the two-part support with four measurement arms as shown in FIG. 9,

[0052] FIG. 11: A side view of the support with the four measurement arms as shown in FIG. 9,

[0053] FIG. 12: A perspective view of a two-part support with six measurement arms according to a fourth embodiment of the invention,

[0054] FIG. 13: A perspective view of the first support component of the two-part support with six measurement arms, as shown in FIG. 12, and

[0055] FIG. 14: A side view of the two-part support as shown in FIG. 12.

[0056] Various structural elements in the figures are identical, so these are denoted by the same indexes.

DETAILED DESCRIPTION

[0057] Accordingly. FIG. 1 shows a coupling device 1, which serves for the detachable formation of a vehicle combination and for measuring coupling forces and/or coupling torques. This vehicle combination consists, for example, of a light towing vehicle 4 and a light trailer vehicle 5. The said vehicle combination, however, can also be a passenger car-caravan combination. The coupling device 1 comprises a measurement device 2 for measuring the coupling forces and/or coupling torques acting upon the drawbar 6 and on the one trailer coupling 3 of the towing vehicle 4.

[0058] In the first example embodiment shown in FIGS. 1, 2, and 3, the measurement device 2 comprises a two-part support 7.1 in the form of a two-arm arrangement, with a first support component 8.1 and a second support component 9.1. The first support component 8.1 has a first central basic portion 10, in this case in the form of a tube. In the first basic portion 10 there are at least two holes 11, 12 which serve to allow the insertion of fixing screws by means of which the said first basic portion 10 can be attached firmly to coupling means 6a of an ordinary ball-head coupling on the trailer side. The trailer-side coupling means 6a of the ball-head coupling is detachable in a known manner and can be articulated to a ball head of a trailer coupling 3 of the towing vehicle 4.

[0059] The second support component 9.1 comprises a second central basic portion 16, in this case also in the form of a tube. However, the first basic portion 10 and the second basic portion 16 can also have a rectangular, U-shaped or other cross-section geometry. In the second basic portion 16 three holes 17, 18, 19 are formed, which are used for a firm screw connection to the drawbar 6 of the trailer vehicle 5. Instead of the said screw connections, however, the two basic portions 10, 16 can also be welded to the trailer-side coupling means 6a or to the drawbar 6. However, a screw connection has the advantage that retrofitting is possible on an already existing trailer vehicle design. In the assembled condition the two-part support 7.1 is arranged fixed between the drawbar 6 of the trailer vehicle 5 and the trailer-side coupling means 6a in order to perform its measurement tasks, in such manner that the drawbar 6 can be coupled onto the trailer coupling 3 of the towing vehicle 4 as has been usual so far.

[0060] At this point it should be said that the coupling device 1 is not limited to a particular type of structure. Thus, with a passenger car-caravan combination, although a ball-head coupling is provided, in the case of a utility vehicle a bar-hitch coupling or a bolt coupling can be used instead. In both cases the two-part support 7.1 can be fitted on the trailer side or on the towing vehicle side, on the one hand in order to articulate the towing vehicle to a trailer vehicle and on the other hand to measure the forces and/or torques acting in the coupling area.

[0061] As illustrated particularly clearly in FIGS. 2 and 3, at an axial end of the basic portion 10 of the first support component 8.1 remote from the towing vehicle two measurement arms 13a, 13b extend diametrically opposite one another. At their respective radially outer ends the first measurement arm 13a and the second measurement arm 13b in each case have an axially projecting eyelet 14a. 14b with respective through-bores 15a. 15b extending with their axes parallel to the longitudinal direction of the first basic portion 10. The through-bores 15a, 15b serve to enable connection of the two measurement arms 13a, 13b to respective associated counter-arms 20a. 20b of the second support component 9.1 of the two-part support 7.1, for example by means of a screw connection. Starting from the end of the basic portion 16 of the second support component 9.1, first and second counter-arms 20a, 20b extend radially and diametrically opposite one another, the radially outer ends of which also have axially projecting eyelets 21a, 21b with axis-parallel through-bores 22a, 22b.

[0062] FIG. 2 shows the two-part support 7.1 in a condition prepared for assembly, wherein the two essentially tube-shaped support components 8.1, 9.1 are positioned against one another with their arm-supporting axial ends 13a and 13b and the counter-arms 20a, 20b directed in line with one another. FIG. 2 shows the first support component 8.1 designed as a sensor carrier as a single component, looking at its back side that faces away from the towing vehicle which in the assembled condition faces toward the second support component 9.1 or the drawbar 6. In the figure it can be seen that on each of the two measurement arms 13a, 13b, close to the eyelets 14a, 14b mentioned, in each case a strain gauge rosette 23, 24 is arranged.

[0063] FIGS. 4 and 5 show in detail, as an example, the structure of the first strain gauge rosette 23 on the first measurement arm 13a. The strain gauge rosette 23 is arranged as close as possible to the eyelet 14a of the measurement arm 13a and is connected firmly, for example in a material-bonded manner, to the material of the measurement arm 13a. The strain gauge rosette 23 consists of a central strain gauge 23b and two further strain gauges 23a, 23c, which are arranged to the right and left of it in each case at an angle of 45° to the central strain gauge 23b. The three strain gauges 23a. 23b and 23c are in each case connected by two electrically conducting cores 25.1, 25.2, 25.3, 25.4, 25.5, 25.6 of a six-core electric line 25 to a measurement-data capture and evaluation unit 26. The second strain gauge rosette 24 (not shown here), which is arranged on the second measurement arm 13b, is of identical form and correspondingly connected to the measurement-data capture and evaluation unit 26 by a further six-core electric line.

[0064] In the other figures, explicit representations of further strain gauge rosettes are omitted. The only important thing is that in all the further example embodiments described in what follows, such a strain gauge rosette is arranged on each measurement arm and is electrically connected to the measurement-data capture and evaluation unit. A possible further development is the additional arrangement of such strain gauge rosettes on one or more of the aforesaid counter-arms for the purpose of increasing the precision of the determination of the coupling forces and coupling torques still more.

[0065] The measurement-data capture and evaluation unit 26 comprises electronic and software technological means, already known as such, by means of which the electrical signals correlated with the strain variations of the strain gauge rosettes 23, 24 can be evaluated in order to determine the forces and torques to which the coupling device 1 is exposed during trailer operation. For example, the measurement-data capture and evaluation unit 26 can be arranged on a printed circuit board, in turn arranged in a protected area of this two-part support 7.1.

[0066] In addition, the measurement-data capture and evaluation unit 26 comprises an electrical or optical interface 27 for the transmission of the coupling force information determined, digitalized and amplified in the measurement-data capture and evaluation unit 26, to an electronic control unit 28. The electronic control unit 28 can for example be part of an electronically controllable brake system and/or an electric drive system of the trailer vehicle 5. Data transmission between the measurement-data capture and evaluation unit 26 and the electronic control unit 28 can take place by way of a wireless, wired or glass-fiber connected data link.

[0067] The example embodiment of the two-arm support 7.1 shown in FIGS. 1 to 3 makes it possible, in particular, to determine a resultant coupling force in one direction, for example in the longitudinal direction of the vehicle. The coupling force can be a traction force or a thrust force.

[0068] FIGS. 6 to 14 show further example embodiments, which differ essentially in the number of measurement arms arranged. Each of these further example embodiments is a symmetrical arrangement of measurement arms which enables a balanced determination of coupling forces and coupling torques in all three spatial directions. In other respects, the previous description is correspondingly applicable.

[0069] Accordingly, in FIGS. 6 to 8 three different views of a second two-part support 7.2 in the form of a three-arm arrangement are shown, namely in perspective, as seen from above, and as seen from the side. In this case a first support component 8.2 comprises three, namely a first to a third, measurement arms 30a, 30b and 30c, which are arranged relative to the respectively adjacent measurement arms offset by an angle of 120°. The three measurement arms 30a. 30b, 30c in each case carry one of the strain gauge rosettes described and generate force signals that enable a three-dimensional evaluation in the measurement-data capture and evaluation unit 26.

[0070] FIGS. 9 to 11 show, in perspective and viewed from the side, a third two-part support 7.3 which is in the form of a four-arm arrangement. In this, a first support component 8.3 shown in detail in FIG. 10 comprises four, namely a first to a fourth, measurement arms 32a, 32b, 32c, 32d arranged offset relative to their adjacent measurement arms by an angle of 90° in each case. A corresponding support component 9.3 has four, namely a first to a fourth, counter-arms 33a, 33b, 33c, 33d, also offset by an angle of 90° relative to one another. The four counter-arms 33a, 33b, 33c, 33d on the second support component 9.3 are largely integrated in a base-plate 34. This provides the arrangement with particularly great stability.

[0071] Finally, FIGS. 12 to 14 show, in perspective and viewed from the side, a fourth two-part support 7.4 in the form of a six-arm arrangement. In this case, a first support component 8.4 shown in detail in FIG. 13 comprises six, namely a first to a sixth, measurement arms 35a, 35b, 35c, 35d, 35e, 35f, each offset relative to its adjacent measurement arms by an angle of 60°. Correspondingly, a second support component 9.4 has six, a first to a sixth counter-arms 36a, 36b, 36c, 36d, 36e, 36f, also arranged offset relative to one another by an angle of 60°. The six measurement arms 35a, 35b, 35c, 35d, 35e, 35f and the six counter-arms 36a, 36b, 36c, 36d, 36e, 36f provide the six-arm arrangement of the fourth two-part support 7.4 with very great stability and force transmission capacity. At the same time the arrangement generates spatially highly resolved force signals which enable very precise determination of the coupling forces and coupling torques.

[0072] Inasmuch as the transmission of comparatively large forces via the arms of the two support components 8.4 and 9.4 seems necessary and the measurement-technological outlay and effort for a three-dimensional determination of the forces and/or torques should be kept low for reasons of cost, then with this six-arm arrangement of the fourth two-part support 7.4 only three of the measurement arms 35a, 35c, 35e offset by an angle of 120° need to be fitted with a strain gauge rosette in each case.

[0073] In conclusion, it should be pointed out that the coupling device with the features of the invention can also be connected to a one-part drawbar of a trailer vehicle. The coupling device is then fixed between the structure of the trailer vehicle and the trailer coupling of the towing vehicle, on the drawbar of the trailer vehicle. Since the two support components of the two-part support of the coupling device are only connected by their radially extending arms, these components are mechanically relatively weak in the force transfer path compared with a one-piece drawbar. When during trailer operation, that is to say when the trailer vehicle is articulated to the towing vehicle and forces are transmitted by way of the drawbar of the trailer vehicle to the towing vehicle or in the converse direction, then this results in a stretching or compression or torsion of the drawbar. This deformation of the drawbar can be measured by the measurement device of the coupling device and then evaluated, as described. Accordingly, this arrangement of a coupling device designed in accordance with the invention is particularly advantageous, since it can be fixed to any conventional trailer vehicle when geometrically adapted to the drawbar concerned.

LIST OF INDEXES

[0074] 1 Coupling device [0075] 2 Measurement device [0076] 3 Trailer coupling (ball-head coupling) [0077] 4 Towing vehicle [0078] Trailer vehicle [0079] 6 Drawbar of the trailer vehicle [0080] 6a Coupling means on the trailer side [0081] 7.1 First two-part support (two-arm arrangement) [0082] 7.2 Second two-part support (three-arm arrangement) [0083] 7.3 Third two-part support (four-arm arrangement) [0084] 7.4 Fourth two-part support (six-arm arrangement) [0085] 8.1 First support component of the first support [0086] 8.2 First support component of the second support [0087] 8.3 First support component of the third support [0088] 8.4 First support component of the fourth support [0089] 9.1 Second support component of the first support [0090] 9.2 Second support component of the second support [0091] 9.3 Second support component of the third support [0092] 9.4 Second support component of the fourth support [0093] Basic portion of the first support component 8.1 [0094] 11 First hole in the first support component 8.1 [0095] 12 Second hole in the first support component 8.1 [0096] 13a First measurement arm of the first support component 8.1 (1st embodiment) [0097] 13b Second measurement arm of the first support component 8.1 (1st embodiment) [0098] 14a Eyelet of the first measurement arm 13a [0099] 14b Eyelet of the second measurement arm 13b [0100] 15a Through-bore in the eyelet of the first measurement arm 13a [0101] 15b Through-bore in the eyelet of the second measurement arm 13b [0102] 16 Basic portion of the second support component 9.1 [0103] 17 First hole in the second support component 9.1 [0104] 18 Second hole in the second support component 9.1 [0105] 19 Third hole in the second support component 9.1 [0106] 20a First counter-arm of the second support component 9.1 (1st embodiment) [0107] 20b Second counter-arm of the second support component 9.1 (1st embodiment) [0108] 21a Eyelet of the first counter-arm 20a [0109] 21b Eyelet of the second counter-arm 20b [0110] 22a Through-bore in the eyelet of the first counter-arm 20a [0111] 22b Through-bore in the eyelet of the second counter-arm 20b [0112] 23 First strain gauge rosette with three strain gauges [0113] 23a Right-hand strain gauge of the strain gauge rosette [0114] 23b Central strain gauge of the strain gauge rosette [0115] 23c Left-hand strain gauge of the strain gauge rosette [0116] 24 Second strain gauge rosette with three strain gauges [0117] 25 Six-core electric line [0118] 25.1-25.6 First core to sixth core of the electric line [0119] 26 Measurement-data capture and evaluation unit [0120] 27 Interface of the measurement-data capture and evaluation unit [0121] 28 Electronic control unit [0122] 30a-30c First to third measurement arm of the first support component 8.2 (2nd embodiment) [0123] 31a-31c First to third measurement arm of the second support component 9.2 (2nd embodiment) [0124] 32a-32d First to fourth measurement arm of the first support component 8.3 (3rd embodiment) [0125] 33a-33d First to fourth measurement arm of the second support component 9.3 (3rd embodiment) [0126] 34 Base-plate on the second support component 9.3 (3rd embodiment) [0127] 35a-35 f First to sixth measurement arm of the first support component 8.4 (4th embodiment) [0128] 36a-36f First to sixth counter-arm of the second support component 9.4 (4th embodiment)