Kingpin for fifth wheel coupling, fifth wheel coupling with kingpin, and utility vehicle with kingpin

Abstract

The invention relates to a kingpin (10) for a fifth wheel coupling of a utility vehicle, having a pin shaft (3) extending along a central axis (M) and having a pin head (2) at the lower end thereof, the pin shaft (3) having a fastening flange (4) at the upper end thereof facing away from the pin head (2), and having a mounting flange (5) which rests on the upper end of the pin shaft (3) and is fastened to the fastening flange (4). According to the invention, a measuring device for detecting the reaction force of the drive dynamics is provided, the measuring device being arranged in a cavity (15) formed between the mounting flange (5) and the upper end of the pin (3) in a fixed state.

Description

[0001] The invention relates to a kingpin for a fifth wheel coupling of a utility vehicle (according to the preamble of claim 1), a fifth wheel coupling with a kingpin as claimed in claim 14, and a utility vehicle with a kingpin as claimed in claim 15.

[0002] The fifth wheel coupling is used to couple a semitrailer (hereinafter referred to as trailer) to a semitrailer tractor. Typically, a main plate with a fifth wheel coupling is installed on the tractor, into which the kingpin (also called kingpin or semitrailer kingpin) installed on the trailer can be inserted and fixed. All loads related to the driving dynamics are then transferred from the tractor to the trailer and vice versa via the kingpin and the fifth wheel coupling.

[0003] The kingpin for the fifth wheel coupling usually has a pin shaft with a pin head. At the opposite end, the pin shaft usually has a fastening flange, by means of which the pin shaft is mechanically fixed to the body or chassis of the trailer via fastening screws. For mechanical reinforcement and connection, a mounting flange is usually provided between the chassis of the trailer and the kingpin, by means of which the kingpin is connected to the chassis of the trailer.

[0004] In the prior art, various measurement methods are proposed to determine the mechanical reaction forces on the fifth wheel coupling. For example, in the case of an auxiliary drive axle of a trailer, the measurement of the reaction forces related to the drive dynamics can be very important. Data can thus be obtained independently of the drive signal of the tractor in order to operate the auxiliary drive axle of the trailer to provide assistance.

[0005] Thus, for example, a solution has been proposed in the prior art for detecting the reaction force acting on the fifth wheel coupling directly via the kingpin on the trailer side or via the pin shaft in order to infer the driving behavior of the tractor from this. Alternatively, solutions have been proposed based on strain gauges located directly in the fastening screws. The auxiliary drive shaft can be operated in driving or braking mode, knowing whether the tractor is applying braking, pulling or changing direction to the trailer. Sensors used in the prior art for detecting forces include strain gauges, load cells, measuring pads and piezoelectric sensors.

[0006] In the variant using measuring washers, these are installed in the screw connection between the kingpin and the trailer and in this way measure the clamping force of the screws. Since the screws are distributed in the circumferential direction around the kingpin or around the fastening flange, the forces acting on the kingpin can be inferred from the tensile and compressive forces in the measuring washers.

[0007] However, the mounting accessories of these sensors have proven difficult to install and maintain in the prior art. In addition, the kingpin shaft is subject to severe dynamic loads during use, so the durability of the measuring device arranged directly on or near the shaft is greatly reduced. In addition, due to installation space considerations, it is not suitable to connect the measuring device directly to the pin.

[0008] Furthermore, strain gauges have proven to be too sensitive to temperature for measuring the reaction forces on the kingpin, for example, and have too large a scatter in their measurement range. Furthermore, by placing the strain gauges inside the fastening screws, a differential measurement method cannot be achieved.

[0009] It is therefore an object of the present invention to overcome the disadvantages of the prior art and to provide a solution by means of which measurements can be carried out on a kingpin or fifth wheel coupling in a simple manner, inexpensively and in a manner that is easy to install, in particular for maintenance purposes. Furthermore, the solution should allow measurements to be carried out in a manner that is insensitive to interference. The kingpin or the pin should be easily replaceable without much effort and without affecting the (force) measuring device. The solution should be particularly suitable in the field of utility vehicles and in tractor-trailers with an auxiliary drive on the trailer and generally with a trailer coupling between the two vehicles.

[0010] The essential features of the invention are specified in claim 1 and in the characterizing parts of claims 14 and 15. Improvements form the subject matter of claims 2 to 13.

[0011] In the case of a kingpin of a fifth wheel coupling for a multi-purpose vehicle, the kingpin has a pin shaft extending along a central axis, the lower end of the pin shaft has a pin head, wherein the pin shaft has a fastening flange at its upper end away from the pin head, and has a mounting flange, which is placed on the upper end of the pin shaft and fixed to the fastening flange. According to the present invention, a measuring device for detecting reaction forces related to driving dynamics is provided, characterized in that the measuring device is arranged in a cavity formed between the mounting flange and the upper end of the pin shaft in a fixed state.

[0012] Due to the spatial, in particular mechanical, separation of the measuring device from the kingpin according to the invention, the forces to which the kingpin is subjected that are relevant for the drive dynamics are significantly reduced. Since the measuring device is arranged in the cavity between the mounting flange and the upper end of the kingpin, it is effectively protected from environmental influences and severe mechanical loads. Furthermore, when replacing a worn kingpin, it is not necessary to replace or rewire the measuring device. It is sufficient to calibrate the measuring device to match the new kingpin.

[0013] The measuring device according to the invention is preferably designed primarily for determining reaction forces relevant to the drive dynamics, which act radially relative to the center axis of the pin and are generated in the area of ​​the kingpin or the fifth wheel coupling due to the driving behavior of the semitrailer tractor. During the action of these radial forces, in particular the distance between the mounting flange and the upper end of the pin changes due to mechanical deformations. The measuring device is preferably designed to measure these distance changes and to determine the radial reaction forces from the measured data.

[0014] Due to the fact that the measuring device is arranged in the cavity between the mounting flange and the upper end of the pin according to the invention, changes in the distance between the mounting flange and the upper end of the pin that are directly related to the acting radial forces can advantageously be detected. At the same time, the measuring device and the electronic connections and wiring preferably associated therewith are largely protected from external environmental influences. In particular, in the lower area of ​​the trailer or chassis, high humidity and high temperature conditions may exist, so that the sensitive measuring device will be exposed to strong influences. The cavity is preferably of disk-shaped or essentially cylindrical design, wherein, in particular, the cavity is of dish-shaped design. This measure additionally supports precise distance measurement, because according to the principle involved, the disk or dish shape does not have an excessively large axial extent along the center axis of the kingpin. Otherwise, the distance between the mounting flange and the upper end of the pin may be too large for the measurement under consideration. In this case, it is important that even relatively small deformations or distance changes can be detected by the measuring device.

[0015] The mounting flange is connected to the upper end of the pin as a separate component. The upper end of the pin is preferably connected to the mounting flange via a fastening flange. In this case, the fastening flange of the pin is preferably detachably fastened to the mounting flange by means of a fastening device. In this case, the fastening device is preferably designed as a screw, wherein the screw is in particular a threaded screw, which in the case of a 2-inch kingpin according to ECE Directive R55-01 fixes the pin to the mounting flange and meets the standards DIN 74080 and ISO 337, wherein in the case of a 3.5-inch kingpin according to ECE Directive R55-01, the threaded screw fixes the pin to the mounting flange and meets the standards DIN 74083 and ISO 4086. At the level of the fastening device, the mounting flange is preferably in full surface contact with the fastening flange in the circumferential direction and is fixed in such a way that the cavity is defined by the connection surface.

[0016] The mounting flange is primarily used as an additional fastening or reinforcement element between the trailer and the pin. The mounting flange can preferably also be used as a mounting element for the measuring device. In this case, a preferred embodiment of the invention envisages that the mounting flange has a dish-shaped base, wherein the dish-shaped base has a lower side facing the cavity for receiving the measuring device. In this case, the dish-shaped base can be arranged parallel to the upper end of the pin. As a further preference, the mounting flange can be essentially of dish-shaped design, wherein the dish-shaped base of the mounting flange can be, in particular, disc-shaped. In addition, it is preferred that the lower side of the dish-shaped base is of flat design. Due to these configurations, a horizontal and uniform support surface for the measuring device is formed on the lower side of the dish-shaped base, so that the measuring device can, for example, be resting and fixed to the lower side of the chassis over its entire surface. The disc-shaped design of the dish-shaped base further supports the design of the cavity for receiving the measuring device.

[0017] In addition, it is preferred that the dish-shaped base has an upper side facing away from the cavity for fixing the mounting flange. In this case, the upper side of the dish-shaped base can be preferably connected to the chassis of the trailer in a material-integrated manner. In this case, the upper side and the lower side of the dish-shaped base can each preferably be of flat design. As a further preference, the upper side of the dish-shaped base is arranged parallel to the lower side of the chassis. In this case, the lower side of the chassis is preferably arranged parallel to the road. In order to enable the upper side to be firmly fixed to the lower side of the chassis, the lower side of the chassis can preferably be of flat design. As a result, a horizontal and uniform support surface for the upper side of the dish-shaped base is formed on the lower side of the chassis, so that the dish-shaped base can, for example, lean against and be connected (for example, in a material-integrated manner) to the lower side of the chassis over its entire surface.

[0018] According to another preferred embodiment of the invention, the upper end of the pin has an inner end face facing the cavity, wherein the upper end of the pin has an outer end face facing the cavity. The two end faces can preferably be of flat design, wherein the end faces can be arranged parallel to the underside of the mounting flange. This measure can, among other things, support the measurement of radial reaction forces.

[0019] The upper end of the pin preferably has an annular projection, which extends in the direction of the dish-shaped base, wherein the annular projection is arranged between the inner end face and the outer end face. The annular projection shortens the distance between the lower side of the dish-shaped base and the upper end of the pin. For example, the sensitivity of the measuring device can be increased thereby, so that even relatively small distance changes can be detected. The annular projection advantageously provides an annular surface, which can be used as a corresponding counter surface of the measuring device, for example, in the case of measurement. In this case, it is preferred that the annular projection is of flat design on its end face facing the lower side of the dish-shaped base. If the annular projection is used as a corresponding measuring counter surface, this measure will additionally improve the measuring accuracy of the measuring device. Irregularities on the end face of the annular projection can effectively interfere with the measurement. In this case, the interference factors must be taken into account accordingly when evaluating the measurement data. In contrast, the flat surface according to the described embodiment significantly supports and improves the measuring process. Here, the ring has a particularly advantageous effect, because the corresponding measuring sensor can be positioned along the preferably continuous annular surface.

[0020] According to another variant embodiment, the measuring device is essentially of disc-shaped design, wherein the measuring device has a cross shape. As a result, the measuring device can be placed against and firmly fixed in place, for example, over its entire surface. Due to the disc shape and the alignment of the measuring device, on the one hand, the measurement of the above-mentioned radial forces is supported, and on the other hand, the measuring device is therefore more compact. This in turn has a favorable effect on aspects related to the installation space. As a result, the measuring device is assembled into a cavity between the underside of the disc-shaped base and the upper end of the pin, which cavity is kept small due to the principle involved. In addition, the disc-shaped design additionally supports differential measurements. In this case, the cross shape of the measuring device can be used, for example, to specify the corresponding direction of the radially acting reaction force to be determined. In addition, due to this special arrangement, an additional improvement in the measuring accuracy can be advantageously obtained. In addition, it is preferred that the measuring device is of symmetrical design. Among other things, this simplifies the work involved in manufacturing and reduces manufacturing costs.

[0021] The measuring device is preferably arranged in a manner centered relative to the central axis of the pin, wherein the measuring device is designed to measure the change in distance relative to the upper end of the pin. The measuring device preferably comprises at least two distance sensors, as a further preferred embodiment at least four distance sensors, for measuring the change in distance between the dish-shaped base and the upper end of the pin. It is preferred here that the individual distance sensors of the measuring device extend radially relative to the central axis. Preferably, a non-contact distance sensor is provided. Physical wear during the measurement is thereby avoided. Non-contact distance sensors are particularly suitable for fast measurements. Furthermore, for example, distance sensors of capacitive design are insensitive to magnetic fields and can therefore be used without problems on electric trailers.

[0022] According to another preferred embodiment of the invention, it is envisaged that the measuring device is arranged directly on the underside of the dish-shaped base, wherein the measuring device is positioned opposite the inner end face and the annular raised portion. In this case, it is further preferred that the measuring device, the underside of the dish-shaped base, the inner end face and the annular raised portion are each arranged in a manner centered relative to the central axis. Therefore, "relatively" means a coaxial or concentric arrangement of the measuring device, wherein the measuring device is spaced apart from the inner end face and the annular raised portion, axially relative to the central axis. The direct arrangement and fixing of the measuring device on the underside of the dish-shaped base additionally supports the mechanical decoupling of the measuring device from the pin. At the same time, the measuring device is thereby decoupled from vibrations that may occur, for example, at the upper end of the pin. In this case, the entire wiring and signal transmission system of the measuring device is preferably also designed to be separated from the pin. In this case, the entire wiring and signal transmission system preferably extends in the direction of the underside of the trailer or in the direction of the chassis. This facilitates the connection of the measuring device and additionally protects the wiring and electronics from external influences and loads.

[0023] As a further preference, the measuring device is arranged plane-parallel to the underside of the dish-shaped base and plane-parallel to the inner end face and the annular raised portion. As a result, the measuring device can, for example, be placed against and fixed to the underside of the dish-shaped base over its entire surface. Furthermore, this creates a sufficient distance from the upper end of the pin, with the result that preferably a distance measurement between the measuring device on the underside of the dish-shaped base and the annular raised portion can be performed. The plane parallelism between the measuring device, the underside of the dish-shaped mounting flange and the upper end of the pin greatly increases the measurement accuracy. At the same time, the realization of differential measurement is thereby supported. The plane-parallel arrangement further ensures that primarily the reaction forces acting radially relative to the center axis as described initially are determined.

[0024] In particular, the measuring device is preferably designed to measure the distance change relative to the annular protrusion. In this case, it is particularly preferred that the distance sensor of the measuring device is arranged opposite to the annular protrusion, wherein the distance sensor is arranged parallel to the annular protrusion. In this case, it is preferred that the radial range of each distance sensor corresponds to the radial range of the annular protrusion. This ensures that the sensor surface of the measuring device corresponds to the relative surface of the annular protrusion. In this case, the measuring device preferably has signal processing electronics, wherein the signal processing electronics of the measuring device are arranged in a manner centered on the central axis of the pin, and wherein the signal processing electronics are radially surrounded by each distance sensor (relative to the central axis). This is advantageous for reasons of installation space and additionally protects the electronics. Signal transmission and wiring system routing and the connection of the electronics are also greatly simplified thereby. In addition to data transmission and processing, the signal processing electronics can also be used to digitize the measured variables and coordinate the corresponding signal transmission. The signal can be fed to the corresponding CAN network for further processing and / or evaluation, and the corresponding parameters for the open-loop and closed-loop control circuits can be formed.

[0025] As a preferred option, at least one distance sensor is aligned radially with respect to the central axis and in the longitudinal direction of the vehicle, wherein at least one further distance sensor is aligned radially with respect to the central axis and in the transverse direction of the vehicle. As a further preferred option, at least two distance sensors are aligned radially with respect to the central axis and in the longitudinal direction of the vehicle, wherein at least two further distance sensors are aligned radially with respect to the central axis and in the transverse direction of the vehicle. In this case, it is particularly preferred that the distance sensors aligned in the longitudinal direction of the vehicle extend radially in opposite directions with respect to the central axis and the longitudinal direction of the vehicle, and the distance sensors aligned in the transverse direction of the vehicle extend radially in opposite directions with respect to the central axis and the transverse direction of the vehicle. This special arrangement of the measuring device and the distance sensors has proven to be particularly advantageous, since it enables the determination of the required radial forces primarily. In this case, the radial forces acting in the longitudinal direction of the vehicle (longitudinal force component) and in the transverse direction of the vehicle (transverse force component) are preferably determined by the measuring device. In the context of the present invention, "transverse" and "longitudinal" refer primarily to all reaction forces acting in a longitudinal dynamic and transverse dynamic manner. These reaction forces act radially with respect to the central axis of the pin and are generated in the area of ​​the fifth wheel coupling or in the area of ​​the kingpin due to relative accelerations and / or decelerations and / or changes in direction between the tractor and the trailer. There may be considerable advantages, in particular for controlling the supporting drive of a trailer, if only the longitudinal and transverse dynamic radial forces are measured and the axial or vertical force components as well as all other force components are largely eliminated even during the measurement phase or can subsequently be excluded or counteracted for open-loop and closed-loop control of the supporting drive.

[0026] Furthermore, the special arrangement of the distance sensors ensures the implementation of differential measurement methods. For example, each of the two opposing distance sensors mentioned above can thereby be evaluated differentially during the measurement process. Mechanical common-mode interferences or temperature-related deviations occurring during the distance change measurement are thereby compensated in particular. Here, the value (output signal) to be transmitted for further evaluation and processing can correspond to the difference between the two potentials. The main advantage of differential measurement is that its sensitivity to interference is significantly reduced. This significantly increases the sensitivity of the measuring device to interference. Each individual signal of the differential transmission is also susceptible to interference and can present a "distorted" value depending on the interference. The difference between the two interfered signals corresponds to the signal to be transmitted, while it itself is not affected, because the distortion degree of the two signals is exactly the same. This type of differential measurement is particularly recommended for the application of the invention on trailers with auxiliary drives.

[0027] According to a further preferred embodiment, the invention envisages that the measuring device is designed as a capacitive sensor unit, wherein the individual distance sensors of the capacitive sensor unit are formed by a capacitive sensor surface. Capacitive sensors are designed for contactless travel measurement, distance measurement and position measurement tasks, but also for measuring the thickness of various materials. The capacitive distance sensor and the (movable) opposing surface form a capacitor, the distance of which determines the capacitance. The opposing surface or the plurality of opposing surfaces can preferably be formed by the upper end of a pin and / or the underside of a dish-shaped base. Due to their high signal stability and resolution, capacitive sensors are used for measurement tasks in laboratories and industry. In this case, the capacitive distance sensor advantageously provides very reliable and precise position detection of objects of almost any material, regardless of gloss, reflectivity, color and surface properties. In addition, capacitive sensors are characterized by a long life and can implement a completely contactless measuring principle.

[0028] The cross shape of the sensor has proven to be particularly advantageous in the case of force measurement on the fifth wheel coupling, because the "cross tip" of the cross shape can be aligned on the dish-shaped mounting flange in the direction of the radial force component to be measured. The capacitive sensor unit can preferably be of symmetrical design, so that the cross shape can be generated, for example, by four identical recesses. This simplifies manufacturing and reduces the production costs of the measuring device. At the same time, the radial measurement direction or alignment of the capacitive sensor surface or distance sensor is thereby ensured. The four capacitive surfaces preferably form the above-mentioned "cross tip". Providing four capacitive surfaces enables a sufficient number of measurements to fully determine the radial reaction forces in the longitudinal and transverse directions of the vehicle. It is particularly preferred here that at least four capacitive sensor surfaces are provided, which extend radially relative to the center axis and form a cross shape. In general, accurate and uniform measurement of the reaction forces on the fifth wheel coupling is thereby supported. In addition, the cross shape can be used to determine an additional force component between two sensor surfaces.

[0029] The invention also relates to a fifth wheel coupling with a kingpin as described above and below, characterized in that the fifth wheel coupling comprises a main plate, wherein the main plate and the fifth wheel coupling are arranged to receive a kingpin on a semitrailer tractor of a utility vehicle.

[0030] The invention also relates to a utility vehicle having a fifth wheel coupling and a kingpin as described above and below.

[0031] According to an alternative embodiment of the invention, additional sensors for further segmentation and refinement of the measuring device can be arranged between the at least four distance sensors. This can be useful and advantageous, in particular if, as required, a finer measurement must be made or an additional force component located directly between the crossing tips is to be measured.

[0032] According to another alternative embodiment, for example, a washer can be placed in the cavity to hold the measuring device instead of the annular raised portion, said washer reducing the distance between the underside of the dish-shaped base and the upper end of the pin. According to this alternative embodiment, the upper end of the pin and the underside of the dish-shaped base can advantageously be of flat design.

[0033] According to another alternative embodiment variant, the measuring device can be arranged directly on the upper end of the pin. It is preferred here that the entire end surface of the upper end of the pin is of flat design to receive the measuring device. Instead, the underside of the dish-shaped base can be correspondingly provided with an annular raised portion extending in the direction of the upper end of the pin. This simplifies manufacturing and saves costs, among other things.

[0034] According to a further alternative embodiment, the signal processing electronics may be formed separately from the measuring device or the distance sensor of the measuring device, for example, so that the signal processing electronics is not arranged in the cavity but in an outer region.

[0035] According to another alternative configuration, other types of contactless distance sensors, such as magnetic strip sensors, can be used instead of contactless capacitive distance sensors for distance measurement. Other types of sensors and configurations are also conceivable, as long as it is ensured that the required loads in relation to the drive dynamics are determined.

[0036] Further features, details and advantages of the invention can be gathered from the wording of the claims and from the following description of exemplary embodiments with reference to the attached drawings. In the drawings:

[0037] Figure 1 A schematic oblique view showing a king pin of a fifth wheel coupling for coupling a trailer to a tractor according to the present invention;

[0038] Figure 2 A partial top view of the kingpin and a schematic diagram of a measuring device according to the present invention are shown;

[0039] Figure 3a shows a bottom view of a kingpin according to the present invention;

[0040] Figure 3b A cross section of a king pin according to the invention is shown.

[0041] Figure 1 A kingpin for a fifth wheel coupling of a utility vehicle is shown, generally indicated at 10. The kingpin 10 includes a pin shaft 3 extending along a central axis M of the kingpin 10. The lower end of the pin shaft 3 is provided with a pin head 2. The lower end of the pin shaft 3 and the pin head 2 are aligned perpendicular to a road (not shown) during coupling, and are inserted into a fifth wheel coupling (not shown) of a tractor and fixed.

[0042] The fastening flange 4 and the dish-shaped mounting flange 5 are arranged at the opposite upper ends of the pin 3, which face the chassis of the trailer or the lower side of the chassis, for fixing the kingpin 10. In this case, the dish-shaped mounting flange 5 is usually pre-installed on the chassis of the trailer in a materially integral manner and can receive and fix the fastening flange 4 of the pin 3. To this end, the dish-shaped mounting flange 5 is placed on the upper end of the pin 3 and fixed on the fastening flange 4. In order to fasten the pin 3 to the dish-shaped mounting flange 5, a fixing device is arranged in the area of ​​the fastening flange 4). The fixing device is designed as a threaded screw 7 and is arranged in the circumferential direction around the pin 3 at a constant spacing.

[0043] right Figure 2 The additional reference to shows that a measuring device for detecting reaction forces relevant to the drive dynamics is arranged on the upper side of the disk-shaped mounting flange 5 , wherein the measuring device is designed as a capacitive sensor unit 20 .

[0044] In this case, the capacitive sensor unit 20 is essentially of disk-shaped design and has a cross shape. The capacitive sensor unit 20 is arranged directly on the disk-shaped mounting flange 5. The disk-shaped mounting flange 5 usually has no opening on its upper side. A cutout is shown in the top view to illustrate the capacitive sensor unit 20.

[0045] The capacitive sensor unit 20 also has four distance sensors, which extend radially relative to the center axis M of the pin 3. The distance sensors are designed as capacitive sensor surfaces S1, S2, S3, S4. The sensor surfaces S1, S3 extend radially relative to the center axis M and extend in the vehicle longitudinal direction FL. In this case, the sensor surfaces S1, S3 extend in opposite directions along the vehicle longitudinal direction FL. The sensor surfaces S2, S4 extend radially relative to the center axis M and extend in the vehicle transverse direction FQ. In this case, the sensor surfaces S2, S4 extend in opposite directions along the vehicle transverse direction FQ.

[0046] Furthermore, the capacitive sensor unit 20 has signal processing electronics 22. The signal processing electronics 22 of the capacitive sensor unit 20 are arranged in a central manner with respect to the central axis M of the pin 3. In this case, the signal processing electronics 22 are radially surrounded (with respect to the central axis M) by the individual capacitive sensor surfaces S1, S2, S3, S4.

[0047] When observing together Figure 3a and Figure 3b , it can be seen that the dish-shaped mounting flange (5) and the fastening flange 4 are connected and detachably fixed to each other in such a way that the mounting flange 5 is in full surface contact with the fastening flange 4 in the circumferential direction at the level of the threaded screws 7, with the result that a cavity 15 is defined by the connection area.

[0048] It can also be seen that the capacitive sensor unit 20 is arranged in the cavity 15. In the fixed state, the cavity 15 is formed between the dish-shaped mounting flange 5 and the upper end of the pin 3. In this case, the cavity 15 is essentially disk-shaped, in particular of dish-shaped design.

[0049] The dish-shaped mounting flange 5 has a dish-shaped base 8, wherein the dish-shaped base 8 has a lower side facing the cavity 15 for receiving the capacitive sensor unit 20. The dish-shaped base 8 is arranged parallel to the upper end of the pin 3, and the lower side of the dish-shaped base 8 is of flat design. The capacitive sensor unit 20 is arranged in particular directly on the lower side of the dish-shaped base 8. In this case, the capacitive sensor unit 20 is against the lower side of the dish-shaped base 8 over its entire area and is fixed. The capacitive sensor unit 20 is also arranged parallel to the lower side plane of the dish-shaped base 8 and parallel to the upper end plane of the pin 3.

[0050] Furthermore, the dished base 8 of the mounting flange 5 has a flat upper side facing away from the cavity 15 for fixing the mounting flange 5. The upper side of the mounting flange 5 is usually connected to the chassis of the trailer (not shown) in a materially integral manner. In this case, the lower side of the chassis is arranged parallel to the road.

[0051] The upper end of the pin 3 has an inner end face 6 facing the cavity 15, wherein the upper end of the pin 3 has an outer end face 14 facing the cavity 15. Both end faces 6, 14 are of flat design and are arranged in a centered manner relative to the central axis M. In this case, the end faces 6, 14 are simultaneously arranged parallel to the underside of the dish-shaped base 8.

[0052] The upper end of the pin 3 also has an annular raised portion 9, which extends in the direction of the dish-shaped base 8, wherein the annular raised portion 9 is arranged between the inner end face 6 and the outer end face 14. The capacitive sensor unit 20 is arranged directly on the lower side of the dish-shaped base 8, wherein the capacitive sensor unit 20 is positioned opposite the inner end face 6 and the annular raised portion 9. The measuring device and the capacitive sensor unit 20, the lower side of the dish-shaped base 8, the inner and outer end faces 6, 14 and the annular raised portion 9 are all arranged in a manner centered with respect to the central axis M.

[0053] The annular raised portion 9 advantageously provides an annular surface as a measuring counter surface to the capacitive sensor unit 20 or the capacitive sensor surfaces S1, S2, S3, S4. In this case, the annular raised portion (9) is of flat design on its annular surface facing the underside of the dish-shaped base 8.

[0054] The capacitive sensor unit 20 is designed to measure the distance change relative to the upper end of the pin 3 so that the reaction force acting radially relative to the central axis can be determined based on the measurement data. In particular, the capacitive sensor unit 20 is designed to measure the distance change relative to the annular raised portion 9. In particular, it can be seen from FIG. 3 that the radial range of each capacitive sensor surface S1, S2, S3, S4 corresponds to the radial range of the annular raised portion 9.

[0055] The invention is not limited to one of the above-described embodiments, but can be modified in many ways. Thus, for example, more or fewer sensor locations can be provided on the capacitive sensor unit.

[0056] The kingpin according to the invention can generally be used to measure the reaction forces on a coupling element between two vehicles. Firstly, the invention relates to the measurement of the reaction forces acting on the fifth wheel coupling or the kingpin of a trailer. In this case, the measurement is used for open-loop and closed-loop control of the trailer support drive. The invention can also be used for closed-loop control of other types of drives in the trailer, for example closed-loop control of a hydraulically driven axle. Alternatively, it is appropriate to use a measuring device to measure the resistance at a separate point.

[0057] All features and advantages arising from the claims, the description and the drawings, including design details, spatial arrangements and method steps, may be essential to the invention either alone or in any combination.

[0058] Reference numerals list

[0059] M Center axis of kingpin

[0060] FL Vehicle longitudinal direction

[0061] FQ Vehicle lateral direction

[0062] AA cross-section plane

[0063] S1 Capacitive sensor surface

[0064] S2 Capacitive sensor surface

[0065] S3 Capacitive Sensor Surface

[0066] S4 Capacitive Sensor Surface

[0067] 2 Pin Head

[0068] 3 Pin

[0069] 4 Fastening flange

[0070] 5 Mounting flange

[0071] 6 Inner end face

[0072] 7 Screws

[0073] 8 Dish base

[0074] 9 Annular raised part

[0075] 10 Kingpin

[0076] 14 Outer end face

[0077] 15 Cavity

[0078] 20 Capacitive sensor units

[0079] 22 Signal processing electronics

Claims

1. A kingpin (10) for a fifth wheel coupling of a utility vehicle, the kingpin (10) having a pin shaft (3) extending along a central axis (M) and having a pin head (2) at its lower end, wherein: The pin shaft (3) has a fastening flange (4) at its upper end away from the pin head (2), and has a mounting flange (5), wherein the mounting flange (5) is placed on the upper end of the pin shaft (3) and fixed on the fastening flange (4), and is characterized in that a measuring device for detecting a reaction force associated with the driving dynamics is provided, wherein the measuring device is arranged in a fixed state in a cavity (15) formed between the mounting flange (5) and the upper end of the pin shaft (3).

2. The kingpin according to claim 1, characterized in that: The measuring device has a cross shape, wherein the measuring device is essentially designed in the shape of a disk.

3. The kingpin according to claim 1 or 2, characterized in that: The upper end of the pin shaft (3) has an inner end surface (6) facing the cavity (15), wherein the upper end of the pin shaft (3) has an outer end surface (14) facing the cavity (15).

4. Kingpin according to any one of the preceding claims, characterized in that The upper end of the pin shaft (3) is provided with an annular protruding portion (9).

5. Kingpin according to any one of the preceding claims, characterized in that The mounting flange (5) has a dish-shaped base (8), wherein the dish-shaped base (8) has a lower side facing the cavity (15) for receiving the measuring device.

6. The kingpin according to claim 5, characterized in that: The measuring device is arranged parallel to the lower side plane of the dish-shaped base (8) and parallel to the upper end plane of the pin shaft (3).

7. The kingpin according to claim 5 or 6, characterized in that: The measuring device is arranged and fixed directly on the lower side of the dish-shaped base (8), wherein the measuring device is positioned opposite to the inner end surface (6) and the annular raised portion (9).

8. Kingpin according to any one of the preceding claims, characterized in that The measuring device is designed to measure a change in distance relative to the upper end of the pin (3), wherein the measuring device comprises at least two distance sensors, preferably at least four distance sensors.

9. The kingpin according to claim 8, characterized in that: The measuring device has signal processing electronics (22), wherein the signal processing electronics are arranged in a manner centered relative to the center axis (M) of the pin (3), and wherein the signal processing electronics (22) are surrounded by individual distance sensors in the radial direction relative to the center axis (M).

10. The kingpin according to claim 8 or 9, characterized in that: The measuring device is arranged in a manner centered relative to the center axis (M) of the pin (3), wherein the individual distance sensors of the measuring device extend radially relative to the center axis (M).

11. The kingpin according to any one of claims 8 to 10, characterized in that At least one distance sensor is aligned radially relative to the center axis (M) and in a longitudinal direction (FL) of the vehicle, wherein at least one further distance sensor is aligned radially relative to the center axis (M) and in a transverse direction (FQ) of the vehicle.

12. A kingpin according to any one of claims 8 to 11, characterized in that At least two distance sensors are aligned radially with respect to the central axis (M) and in a longitudinal direction (FL) of the vehicle, wherein at least two further distance sensors are aligned radially with respect to the central axis (M) and in a transverse direction (FQ) of the vehicle.

13. A kingpin according to any one of claims 8 to 12, characterized in that The measuring device is designed as a capacitive sensor unit (20), wherein the individual distance sensors of the capacitive sensor unit (20) are formed by capacitive sensor surfaces (S1, S2, S3, S4).

14. A fifth wheel coupling having a kingpin as claimed in any one of the preceding claims, characterised in that The fifth wheel coupling includes a main plate, wherein the main plate and the fifth wheel coupling are arranged to receive a king pin on a semi-trailer tractor of a utility vehicle.

15. A utility vehicle having the fifth wheel coupling and kingpin as claimed in claim 14.

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