Weighing system for direct detection of the support load of semi-trailers and semi-trailers with such a weighing system

Abstract

The present invention relates to a weighing system (1) for directly measuring the support load of a semi-trailer (2), comprising at least: a fastening means (11) for attaching a kingpin (111) to a frame (22) of the semi-trailer (2); a fifth wheel plate (12) for interacting with a fifth wheel coupling (31) of a tractor unit (3); and a measuring system (13) arranged between the fastening means (11) and the fifth wheel plate (12), wherein the measuring system (13) is configured to measure a force acting on the fifth wheel plate (12). It is characterized in that the kingpin (111) is rigidly connected to the frame (22) by means of the fastening means (11); and that the fifth wheel plate (12) is configured to move independently relative to the kingpin (111).In the weighing system (1) according to the invention, almost all horizontal forces generated by the vehicle dynamics are directed into the frame (22) via the decoupled kingpin (111) without passing through the measuring system (13), and mainly vertical forces are taken into account in the support load measurement via the semi-trailer plate (12), which advantageously increases its accuracy.

Description

[0001] The present invention relates to a weighing system [1] for the direct measurement of the support load of a semi-trailer [2] according to the preamble of claim 1 and to a semi-trailer [2] with such a weighing system [1] according to the preamble of claim 10.

[0002] The importance of universally applicable trucks (trucks), which are preferably also used on farms (so-called agricultural trucks or agro-trucks), has steadily increased in recent years. The term "agricultural trucks" refers to truck tractors equipped with a fifth wheel coupling, ball coupling, or power take-off shafts. They pull agricultural trailers, machinery, and / or semi-trailers, and can therefore perform certain agricultural tasks in a field that often involve the transport of materials. These include, for example, spreading lime, manure, and / or mineral fertilizers on a field or pressing square bales of hay or straw.At the same time, such agricultural trucks also enable the rapid transport of harvested crops from the field to the buyer via public roads, thus offering advantages over conventional tractors when longer distances must be covered. To comply with weight limits when driving on public roads, but especially from the perspective of so-called "precision farming," real-time weight recording of the agricultural truck, especially the trailer weight, is necessary.

[0003] "Precision farming" is a method of site-specific and targeted management of agricultural land. Local and ecologically site-specific information is used to measure nutrient availability, yield expectations, and damage pressure on the actual crops on a site-specific basis. Based on these measurements, the extent of input use (fertilizer rate, seed rate, and / or pesticide rate) as well as machine and labor time are determined. This approach can advantageously maximize yield and product quality and prevent environmental pollution caused by over-fertilization or the excessive use of pesticides. At the same time, it ensures comprehensive documentation of the respective production process.

[0004] Therefore, high demands are placed on the accuracy of weight recording. In addition to the total weight of the vehicle, which comprises the weight of the tractor unit and the trailer ("semi-trailer") including its load, the real-time recording of the payload during use, i.e., in particular, the recording of the weight change of the semi-trailer during use, is particularly relevant. When recording the weight of a semi-trailer, a distinction is usually made between the so-called nose load, i.e., the load that the semi-trailer supports on the tractor unit in the area of ​​the coupling, and the so-called axle load, i.e., the load that is transferred to the road via the semi-trailer axles. The nose load and the axle load can be measured independently of each other, and the total semi-trailer weight can then be determined by adding the two values.

[0005] In this context, EP 2 028 459 A1 discloses, for example, a device for determining the load state of a tank container with at least two sensors, wherein at least a first sensor is arranged on a coupling between the towing vehicle and the trailer and / or on a support leg of the trailer and at least one further sensor is arranged on a wheel axle of the trailer.

[0006] DE 195 08 239 A1 also discloses a truck trailer weighing system in which the axle weight is determined via the trailer's axle suspension, and the support load is determined via a weight measuring device located between the trailer and a kingpin connecting the tractor and the trailer. The weight measuring device comprises a force transmission element and a weight measuring device, which are connected to the trailer's kingpin via a connecting piece. The connecting piece and kingpin are firmly connected to each other and interact as a unit with the fifth wheel coupling of the respective tractor.

[0007] EP 0 607 855 A1 describes a device for measuring and displaying the loading status of a semi-trailer, in which a pressure or force sensor is arranged on the support coupling of the tractor with the semi-trailer, in particular between a sliding plate and a fifth wheel plate of the semi-trailer in the area of ​​the kingpin of the tractor.

[0008] Finally, DE 44 02 528 C2 and WO 2021 / 046 091 A1 disclose arrangements of measuring means on a semi-trailer vehicle with a fifth wheel coupling for connecting the tractor unit and the semi-trailer, wherein the measuring means are arranged between the semi-trailer and the tractor unit at their connecting parts between the semi-trailer and the fifth wheel coupling.

[0009] What all of these devices have in common is that the support load is always determined by measuring the force acting on the kingpin. This involves measuring not only vertical forces, which are primarily caused by the loading condition of the respective semi-trailer, but also horizontal forces generated by driving dynamics. This disadvantageously leads to a falsification of the support load determination results.

[0010] Based on this, the present invention is based on the object of providing a weighing system which is improved compared to the prior art and which enables particularly accurate support load determinations and at the same time is cost-effective to manufacture and quick to maintain and repair.

[0011] This object is achieved by a weighing system for directly measuring the support load of a semi-trailer having the features of independent patent claim 1 and by a semi-trailer having such a weighing system according to patent claim 10.

[0012] The weighing system [1] according to the invention for directly measuring the support load of a semi-trailer [2] comprises at least one fastening means

[11] for fastening a kingpin

[111] to a frame

[22] of the semi-trailer [2]; a trailer plate

[12] for interacting with a fifth wheel coupling

[31] of a tractor [3]; and a measuring system

[13] arranged between the fastening means

[11] and the trailer plate

[12] , wherein the measuring system

[13] is designed to measure a force acting on the trailer plate

[12] . It is distinguished from generic weighing systems in that the kingpin

[111] is firmly connected to the frame

[22] by means of the fastening means

[11] ; and that the trailer plate

[12] is designed to move independently of the kingpin

[111] .

[0013] A kingpin

[111] , which is firmly connected to the frame

[22] and relative to which the trailer plate

[12] can move independently, advantageously leads to a mechanical decoupling of the kingpin

[111] and the trailer plate

[12] as a means of interaction between the semi-trailer [2] and the fifth wheel coupling

[31] of the towing vehicle [3]. Due to this decoupling, the trailer plate

[12] is advantageously subjected to mainly vertical forces, which are taken into account by the measuring system

[13] to determine the support load. The horizontal forces that arise during steering maneuvers due to friction between the fifth wheel coupling

[31] of the tractor and the trailer plate

[12] are small compared to driving dynamic forces on the kingpin

[111] .In the weighing system according to the invention [1], almost all horizontal forces generated by driving dynamics are guided into the frame

[22] via the decoupled kingpin

[111] without passing through the measuring system

[13] , which advantageously increases the accuracy of the support load measurement.

[0014] Further advantageous embodiments and developments, which can be used individually or in combination with one another, are the subject of the dependent claims.

[0015] In a preferred embodiment of the invention, it has proven useful if the frame

[22] comprises at least one abutment

[21] , preferably two abutments

[21] , in the area of ​​the fastening means

[11] , preferably in the area of ​​the kingpin

[111] , which abutment is designed to come into operative connection with the measuring system

[13] , wherein the connection between the abutment

[21] and the measuring system

[13] is made in particular via a screw connection. The abutment or abutments

[21] advantageously absorb the forces transmitted from the trailer plate

[12] to the measuring system

[13] and transmit them to the frame

[22] . The screw connection advantageously facilitates maintenance and the replacement of wearing parts.

[0016] In a further preferred embodiment, it has proven advantageous if the trailer plate

[12] is operatively connected to the frame

[22] , in particular to its abutment

[21] , via the measuring system

[13] . The connection between the trailer plate

[12] and the measuring system

[13] is made, in particular, via a screw connection. An operative connection of the trailer plate

[12] to the frame

[22] , in particular to its abutment

[21] , via the measuring system

[13] advantageously enables the measurement of the forces generated when the trailer plate

[12] is supported on the fifth wheel coupling

[31] . Here, too, the screw connection advantageously facilitates maintenance and the replacement of wearing parts.

[0017] A particularly preferred embodiment of the invention is one in which the measuring system

[13] comprises at least one double shear beam load cell, preferably two double shear beam load cells. Double shear beam load cells are load cells with two spring elements and strain gauges arranged thereon, which register deformations of the spring elements and convert them into electrical signals. They are used to measure shear forces. Measuring systems

[13] comprising at least one double shear beam load cell advantageously require a particularly small installation space for attachment to the trailer plate

[12] and / or the abutment

[21] of the frame

[22] .

[0018] It is advantageous if the measuring system

[13] , in particular the at least one double shear beam load cell, is arranged between the fastening means

[11] and the semi-trailer plate

[12] in such a way that, during use, its longitudinal axis

[131] points in the direction of travel of the semi-trailer [2]. In the event of a bending of the side regions of the semi-trailer plate

[12] , a measuring system

[13] arranged transversely to the direction of travel, in particular a double shear beam load cell arranged in this way, can only detect said bending on one side. The shear displacement is then disadvantageously amplified on this side and can falsify the measurement of the force acting on the semi-trailer plate

[12] . In a measuring system

[13] oriented in the direction of travel, torsional forces act on the measuring system

[13] , in particular a double shear beam load cell, instead of said bending of the semi-trailer plate

[12] , which torsional forces are not detected by the measuring system

[13] .This advantageously increases the measurement accuracy of the measuring system

[13] .

[0019] In a further preferred embodiment of the invention, the fastening means

[11] can comprise a mounting plate

[112] which has at least one longitudinal member

[113] for operative connection to the kingpin

[111] and at least one cross member

[116] which runs substantially perpendicular to the longitudinal member

[113] . A mounting plate

[112] advantageously connects the longitudinal members and cross members of the frame

[22] to one another and acts as a shear field for the first frame segment. With such a shear field, the frame

[22] can absorb longitudinal forces and the mounting plate

[112] can absorb shear forces, whereby this geometric division of the force transmission advantageously allows a considerably higher force introduction with less material expenditure.

[0020] It has proven to be advantageous if the mounting plate

[112] comprises at least two longitudinal ribs [114; 115], which run parallel to the longitudinal member

[113] at least in sections.

[0021] Furthermore, it is advantageous if the longitudinal ribs [114; 115] and the longitudinal member

[113] are each connected to one another via at least one, preferably two, transverse elements

[117] . Longitudinal ribs [114; 115], which run at least partially parallel to the longitudinal member

[113] , on the one hand, create a moment of inertia and thus advantageously prevent deformation of the mounting plate

[112] , which can be caused in particular by the action of vertical forces on the mounting plate

[112] or due to the force introduction by the kingpin

[111] . On the other hand, together with the transverse element(s)

[117] , which are preferably each designed to be long enough to connect the longitudinal member

[113] to at least one of the longitudinal ribs [114; 115], they form a further frame structure within the fastening means

[11] , which in turn advantageously leads to a further increase in the stability of the fastening means

[11] .

[0022] Finally, in a preferred embodiment of the invention, the trailer plate

[12] can comprise a recess

[124] for the king pin

[111] , wherein the recess

[124] is preferably circular and wherein the diameter of the recess

[124] is 16 to 24 mm, preferably 20 mm, larger than the diameter of a receiving plate

[1112] of the king pin

[111] , or 5 to 10 mm, preferably 7 mm, larger than the diameter of a pin area

[111] of the king pin

[111] . A recess

[124] designed in this way offers a sufficiently large distance on all sides for the kingpin

[111] , which is guided through the recess

[124] during use, in order to avoid contact between the kingpin

[111] and the trailer plate

[12] , in particular contact between the receiving plate

[1112] and / or the pin area

[1111] of the kingpin

[111] and the trailer plate

[12] .

[0023] A semi-trailer [2] according to the invention comprises a frame

[22] , at least one axle

[23] arranged on the frame

[22] , and at least one axle load measuring system [4] for measuring the weight of the semi-trailer [2] acting on the at least one axle

[23] . It is also characterized by a weighing system [1] as described above. A combination of the data on the support load obtained by the weighing system [1] according to the invention and the data on the axle load of the semi-trailer [2] obtained via the axle load measuring system [4] can advantageously provide real-time data on the loading status or the load weight of the semi-trailer [2], in particular during travel. Control of the application rate of fertilizer on a field, for example, can thus be advantageously varied because the load is continuously monitored.The weighing system according to the invention [1] advantageously provides particularly accurate measured values ​​for the support load, which are then incorporated into the further calculations and thus increase the overall accuracy of the load weight determination.

[0024] Additional details and further advantages of the invention are described below with reference to preferred embodiments, to which the present invention is not limited, and in conjunction with the accompanying drawings.

[0025] It shows schematically: Fig. 1 shows a side view of a tractor [3] with an embodiment of a semi-trailer [2] of an agricultural truck according to the invention connected thereto via a fifth wheel coupling

[31] ; Fig. 2 shows an embodiment of a weighing system [1] according to the invention in use, wherein a kingpin

[111] is connected to a fifth wheel coupling

[31] , in a view from a tractor [3] towards a semi-trailer [2]; Fig. 3 shows a first embodiment of a fastening means

[11] without measuring system

[13] , abutment

[21] and frame

[22] ; Fig. 4 shows a second embodiment of a fastening means

[11] now with measuring system

[13] and abutment

[21] of the frame

[22] ; and Fig. 5 shows an embodiment of a semi-trailer plate

[12] .

[0026] In the following description of preferred embodiments of the present invention, like reference numerals designate like or comparable components.

[0027] In Fig. 1a side view of a tractor 3 is shown with an embodiment of a semi-trailer 2 of an agricultural truck according to the invention connected thereto via a fifth wheel coupling 31.

[0028] A semi-trailer 2 according to the invention comprises a frame 22, at least one axle 23 arranged on the frame 22 and at least one axle load measuring system 4 for measuring the weight force of the semi-trailer 2 acting on the at least one axle 23. In Fig. 1A semi-trailer 2 with two axles 23 and two axle load measuring systems 4 arranged in the area of ​​the axles 23 is shown as an example. Various state-of-the-art systems can be used as the axle load measuring system 4. For example, in semi-trailers 2 equipped with an air suspension, the axle load can be determined via the pneumatic pressure in the chassis. In chassis with hydraulic suspension, the axle load can be determined via an increase or decrease in the hydraulic pressure. So-called weighbridge systems are also known, in which the chassis and the body of the semi-trailer each have their own supporting frame, and between this "double frame" load cells for determining the axle load are arranged.In addition, the state of the art also includes examples of axle load measuring systems based on angle measurement or on measuring the changing magnetic field when a ferromagnetic wheel stub is deformed due to loading.

[0029] When using the agricultural truck, the tractor 3 and the semi-trailer 2 are normally connected via a fifth wheel coupling 31. The fifth wheel coupling 31 can, as shown in Fig. 1shown, be arranged on the frame 32 of the tractor 3, in particular in the area of ​​the rear axle of the tractor 3 or between the front axle and the rear axle of the tractor 3 and preferably has a receptacle for a connecting element on the semi-trailer 2 which is designed to correspond to said receptacle, the so-called kingpin or king pin 111. A large number of differently designed fifth wheel couplings 31 are known from the prior art, all of which can be used in conjunction with the weighing system 1 according to the invention, since said weighing system 1 is arranged exclusively on the semi-trailer 2 and is thus advantageously independent of the design of the tractor 3.

[0030] In the coupling area between the tractor unit 3 and the semitrailer 2, the semitrailer 2 according to the invention comprises a weighing system 1 according to the invention for directly measuring the support load of the semitrailer 2 (shown schematically here). By combining the support load data obtained by the weighing system 1 according to the invention and the axle load data of the semitrailer 2 obtained via the axle load measuring system 4, real-time data on the loading status or the payload of the semitrailer 2 can advantageously be obtained, particularly during travel. For example, in an agricultural truck with a semitrailer 2 according to the invention, the amount of fertilizer being distributed over an agricultural area can be continuously tracked during application, allowing the dosage to be advantageously adapted to the respective environmental conditions in accordance with the "precision farming" concept.

[0031] Fig. 2now shows an embodiment of a weighing system 1 according to the invention in use, wherein a kingpin 111 is connected to a fifth wheel coupling 31. Fig. 2 represents a view from the tractor 3 towards the semi-trailer 2, i.e. opposite the direction of travel.

[0032] A weighing system 1 according to the invention for directly measuring the support load of a semitrailer 2 comprises at least one fastening means 11 for attaching a kingpin 111 to a frame 22 of the semitrailer 2; a trailer plate 12 for interacting with a fifth wheel coupling 31 of a tractor 3; and a measuring system 13 arranged between the fastening means 11 and the trailer plate 12. The measuring system 13 is configured to measure a force acting on the trailer plate 12. In the example shown here, the kingpin 111 is inserted into the receptacle of the fifth wheel coupling 31 arranged on the frame 32 of the tractor 3 and can be secured against unintentional release by a lock 311.During use, the trailer plate 12 of the weighing system 1 slides on the top side of the fifth wheel coupling 31. To minimize wear, both the top side of the fifth wheel coupling 31 and the side of the trailer plate 12 facing the fifth wheel coupling 31 can be coated with grease. This sliding or contact between the fifth wheel coupling 31 and the trailer plate 12 represents an interaction within the meaning of the present invention.

[0033] According to the invention, the kingpin 111 is firmly connected to the frame 22 by means of the fastening means 11 and the trailer plate 12 is designed to move independently of the kingpin 111.

[0034] The Fig. 3 and 4 show different designs of fastening devices 11. In Fig. 3 a first embodiment of a fastening means 11 without measuring system 13, abutment 21 and frame 22 is shown, whereas in Fig. 4a second embodiment of a fastening means 11 is now shown with measuring system 13 and abutment 21 of the frame 22.

[0035] For the firm connection of the kingpin to the frame 22, the fastening means 11 can preferably comprise a mounting plate 112, which can have at least one longitudinal member 113 for operative connection with the kingpin 111 and at least one cross member 116, which runs substantially perpendicular to the longitudinal member 113. The longitudinal member 113 can be designed as a square tube, which can be broken through a front side of the mounting plate 112 and can be integrally connected, in particular welded, to at least the cross member 116 (cf. Fig. 3). The kingpin 111 can then in turn be firmly connected to the fastening means 11, in particular to the mounting plate 112 and / or the longitudinal member 113, and / or to the frame 22, wherein the firmly connected connection is preferably created by welding. In contrast to the prior art, in which the kingpin 111 is firmly connected to the trailer plate 12, in this way the force acting on the trailer plate 12 by the fifth wheel coupling 31 can advantageously be mechanically decoupled from the force acting on the kingpin 111 by the fifth wheel coupling 31.

[0036] The frame 22 can have at least one abutment 21 in the area of ​​the fastening means 11, preferably in the area of ​​the king pin 111, or preferably as shown in the Fig. 2 and 4shown comprise two abutments 21. Said abutments 21 can in particular be designed to come into operative connection with the measuring system 13, wherein the connection between abutment 21 and measuring system 13 can in particular be made via a screw connection. Fig. 2 to 4 It can also be seen that the mounting plate 112 can comprise at least two longitudinal ribs 114 and 115, which can run parallel to the longitudinal member 113, at least in sections. Like the longitudinal member 113, the longitudinal ribs 114 and 115 can also be broken through the front side of the mounting plate 112 and integrally connected, in particular welded, to said mounting plate 112. The opening through the front side of the mounting plate 112 advantageously facilitates the production of the welded joints.

[0037] The abutment(s) 21 can then preferably be arranged on said longitudinal ribs 114 and 115, in particular welded thereto. The longitudinal ribs 114 and 115 and the longitudinal beam 113 can each be connected via at least one (cf. Fig. 4 ), preferably two (cf. Fig. 3 ), transverse elements 117 are connected to one another, whereby the stability of the fastening means 11 is advantageously increased.

[0038] In Fig. 2It can also be seen that the trailer plate 12 can be operatively connected to the frame 22, in particular its abutment 21, via the measuring system 13, wherein the connection between the trailer plate 12 and the measuring system 13 can be made, in particular, via a screw connection. For this purpose, the mounting plate 112 preferably has openings 1121, which are positioned to correspond to the position of the abutments 21 of the frame 22 and the abutments 121 of the trailer plate 12 and thus advantageously enable the operative connection of the abutment 21 of the frame 22, the measuring system 13, and the abutment 121 of the trailer plate 12. Furthermore, a distance D can be provided between the mounting plate 112 and the trailer plate 12, which distance can advantageously allow deformation of the measuring system 13, in particular the double shear beam load cell. Said distance D can have a value between 8 and 10 mm, preferably 9 mm.The measuring system 13 preferably comprises at least one, but preferably two, double-shear beam load cells, as shown here, which are arranged in particular between the fastening means 11 and the trailer plate 12 such that, during use, their longitudinal axis 131 points in the direction of travel of the semi-trailer 2. In the example shown here, the two measuring systems 13, designed as double-shear beam load cells, are arranged to the left and right of the longitudinal member 113 and beyond the longitudinal ribs 114 and 115, run parallel to them, and thus point in the direction of travel of the semi-trailer 2.

[0039] Fig. 5 finally shows a design of a trailer plate 12 in a perspective view.

[0040] The trailer plate can consist of seven individual parts, which are preferably connected to one another in a materially bonded manner, in particular welded to one another: On a base plate, which preferably measures 850 x 850 mm and to which the vertical load is transferred, in particular two abutments 121 for the measuring system(s) 13, two edge stiffeners 122 and / or two transverse stiffeners 123 can be arranged.

[0041] The trailer plate 12 also comprises in particular a recess 124 for the king pin 111, wherein the recess 124 is preferably circular and wherein the diameter of the recess 124 is preferably larger than the diameter of the king pin 111. As in Fig. 2As shown by way of example, the kingpin 111 can have an approximately mushroom-shaped structure, wherein the mushroom head can be formed by a receiving plate 1112 and the mushroom base by a pin region 1111. The kingpin 111 can be connected, in particular, to the mounting plate 112 via the receiving plate 1112 in a materially bonded manner, preferably by a welded connection. The receiving plate 1112 and the pin region 1111 of the kingpin 111 can form two separate components; in particular, the pin region 1111 of the kingpin 111 can be screwed to the receiving plate 1112 of the kingpin 111. However, the kingpin 111 with the receiving plate 1112 and the pin region 1111 can also be formed as a single piece.

[0042] The recess 124 advantageously ensures a distance of 8 to 12 mm, preferably 10 mm, from the receiving plate 1112 of the king pin 111 guided through the recess 124 or a distance of 2.5 to 5 mm, preferably 3.5 mm, from the pin region 1111 of the king pin 111 guided through the recess 124. In the region of the recess 124, the two abutments 121 can then be arranged preferably opposite one another around said recess 124 and the two transverse stiffeners 123 can each be arranged approximately perpendicularly thereto. The abutments 121 can be designed in particular as solid, preferably 25 mm thick sheets, which can comprise bores, in particular through-bores and / or stepped bores, for screw connection to the measuring system 13 and which advantageously increase the basic rigidity of the trailer plate 12, in particular in the area of ​​the measuring systems 13.In one embodiment, the abutments 121 can, for example, each have four bores aligned correspondingly to the longitudinal axis 131 of the measuring system 13, wherein the two bores arranged in the central region of the measuring system 13 and thus also of the respective abutment 121 with respect to the longitudinal axis 131 of the measuring system 13 can be designed as stepped bores and the bores arranged in the outer region with respect to the longitudinal axis 131 of the measuring system 13 and thus also of the respective abutment 121 can be designed as through bores.

[0043] The two edge stiffeners 122 can preferably be arranged in the edge region of the trailer plate 12 and advantageously serve to locally stiffen the areas outside the measuring system(s) 13 and thus prevent deformation of the trailer plate 12 during tilting, tipping, or trampling (= rocking or swinging of the rigid axle). In order for the edge stiffeners 122 to offer the stiffness of a plate of equal thickness, weld holes can preferably be provided in the edge stiffeners 122 to ensure a frictional connection. The weld holes can be designed on the long sides, in particular, as three equal thicknesses, i.e., polygons always at the same distance from the opposite side. Finally, the transverse stiffeners 123 can preferably be designed as a flat part to advantageously reduce loss of saddle height.Due to the targeted arrangement of the edge stiffeners 122 and transverse stiffeners 123 on the base plate of the trailer plate 12, this advantageously has a weight about one third lower than a trailer plate of the state of the art manufactured entirely in one thickness, with the same stability for force absorption.

[0044] A trailer plate 12 configured in this way also advantageously enables the kingpin 111 to be firmly connected to the fastening means 11, in particular by welding, without having to support the receiving plate 1112 of the kingpin 111 in order to achieve the required coupling dimensions. The trailer plate 12 can preferably be made of a high-strength steel such as S700MC steel or S900 steel and preferably has a total assembly thickness of 30 to 36 mm, particularly preferably 33 mm.

[0045] The present invention relates to a weighing system 1 for directly measuring the support load of a semi-trailer 2, comprising at least: a fastening means 11 for fastening a kingpin 111 to a frame 22 of the semi-trailer 2; a trailer plate 12 for interacting with a fifth wheel coupling 31 of a tractor 3; and a measuring system 13 arranged between the fastening means 11 and the trailer plate 12, wherein the measuring system 13 is configured to measure a force acting on the trailer plate 12. It is characterized in that the kingpin 111 is firmly connected to the frame 22 by means of the fastening means 11; and in that the trailer plate 12 is configured to move independently of the kingpin 111.In the weighing system 1 according to the invention, almost all horizontal forces generated by driving dynamics are guided into the frame 22 via the decoupled kingpin 111 without passing through the measuring system 13, and mainly vertical forces are taken into account in the support load measurement via the trailer plate 12, which advantageously increases its accuracy. List of reference symbols

[0046] 1Weighing system 11Fasteners 111King pin 1111King pin area (111) 1112King pin support plate (111) 112Mounting plate 1121Opening 113Longitudinal member 114Longitudinal rib 115Longitudinal rib 116Cross member 117Cross element 12Trailer plate 121Abutment 122Edge stiffener 123Cross stiffener 124Recess for king pin (111) 13Measuring system 131Longitudinal axle 2Semi-trailer 21Frame abutment 22Frame 23Axle 3Tractor 31Fifth wheel coupling 311Lock 32Tractor frame (3) 4Axle load measuring system DDistance between trailer plate (12) and mounting plate (112)

Claims

1. Weighing system (1) for directly measuring the support load of a semi-trailer (2), comprising at least: - a fastening means (11) for fastening a kingpin (111) to a frame (22) of the semi-trailer (2); - a trailer plate (12) for interacting with a fifth wheel coupling (31) of a tractor (3); and - a measuring system (13) arranged between the fastening means (11) and the trailer plate (12), wherein the measuring system (13) is configured to measure a force acting on the trailer plate (12); characterized by - that the kingpin (111) is firmly connected to the frame (22) by means of the fastening means (11); - and that the trailer plate (12) is designed to move independently of the kingpin (111).

2. Weighing system (1) according to claim 1, characterized in thatthe frame (22) in the region of the fastening means (11), preferably in the region of the kingpin (111), comprises at least one abutment (21), preferably two abutments (21), which is designed to come into operative connection with the measuring system (13), wherein the connection between the abutment (21) and the measuring system (13) is made in particular via a screw connection.

3. Weighing system (1) according to claim 1 or 2, characterized in that the trailer plate (12) is operatively connected to the frame (22), in particular its abutment (21), via the measuring system (13), wherein the connection between the trailer plate (12) and the measuring system (13) is made in particular via a screw connection.

4. Weighing system (1) according to one of claims 1 to 3, characterized in that the measuring system (13) comprises at least one double shear beam load cell, preferably two double shear beam load cells.

5. Weighing system (1) according to claim 4, characterized in thatthe measuring system (13), in particular the at least one double shear beam load cell, is arranged between the fastening means (11) and the trailer plate (12) in such a way that, in use, its longitudinal axis (131) points in the direction of travel of the semi-trailer (2).

6. Weighing system (1) according to one or more of the preceding claims, characterized in that the fastening means (11) comprises a mounting plate (112) which has at least one longitudinal member (113) for operative connection to the kingpin (111) and at least one transverse member (116) which runs substantially perpendicular to the longitudinal member (113).

7. Weighing system (1) according to claim 6, characterized in that the mounting plate (112) comprises at least two longitudinal ribs (114; 115) which run at least partially parallel to the longitudinal member (113).

8. Weighing system (1) according to claim 7, characterized in thatthe longitudinal ribs (114; 115) and the longitudinal member (113) are each connected to one another via at least one, preferably two, transverse elements (117).

9. Weighing system (1) according to one or more of the preceding claims, characterized in that the trailer plate (12) comprises a recess (124) for the king pin (111), wherein the recess (124) is preferably circular and wherein the diameter of the recess (124) is - 16 to 24 mm, preferably 20 mm, larger than the diameter of a receiving plate (1112) of the king pin (111); or - 5 to 10 mm, preferably 7 mm, larger than the diameter of a pin region (1111) of the king pin (111).

10. Semi-trailer (2) with a frame (22), at least one axle (23) arranged on the frame (22) and at least one axle load measuring system (4) for measuring the weight force of the semi-trailer (2) acting on the at least one axle (23), characterized bya weighing system (1) for directly measuring the support load of the semi-trailer (2) according to one of claims 1 to 9.