Adapter for mounting a load carrier on a ball-type trailer hitch, connection device for an adapter and load carrier system for a motor vehicle

Abstract

Adapter (10) for mounting a load carrier on a ball-type trailer coupling (12) with the following features: • a base body (14) with a base (16), a lid (18) arranged opposite the base (16) and at least one side wall (20, 22, 24) connecting the base (16) to the lid (18), • wherein the base (16) has a base opening (26) for the passage of a shaft (28) of the ball-head trailer coupling (12) and a contact surface (30) for the contact of a ball head (32) of the ball-head trailer coupling (12), and wherein the cover (18) has a cover opening (36) with a longitudinal axis (38), wherein a first thread (42) having a first thread diameter (40) is arranged around the longitudinal axis (38), which is in operative connection with the cover (18) and into which a threaded stud (44) for fastening the adapter (10) to the ball-head trailer coupling (12) can be screwed, characterized in that along the longitudinal axis (38) above the first thread (42) around the longitudinal axis (38) a second thread (66) having a second thread diameter (64) is arranged, into which a threaded plug (68) for securing the threaded stud (44) can be screwed.

Description

[0001] The invention relates to an adapter for mounting a load carrier on a ball-head trailer coupling, a connection device for an adapter and a load carrier system for a motor vehicle.

[0002] Ball-type towbars are widely used on motor vehicles. They represent the standard design for towbars, particularly on passenger cars. Besides towing trailers, these types of towbars are also used to carry load carriers such as transport containers, bicycle carriers, or loading aids to facilitate loading and unloading the trunk.

[0003] Many load carriers are frequently mounted and dismounted. In particular, attaching loading aids while driving is often undesirable or not permitted, resulting in mounting and dismounting for every loading operation. If another load carrier is already attached to the towbar, it must also be removed for the use of the loading aid and then potentially remounted. Load carriers intended for use only when stationary often have less stringent mounting requirements.

[0004] The following are cited as state of the art: DE 94 09 504 U1, NL 1022234 C, FR 2 750 376 A1, DE 10 2014 115 435 A1 and DE 202 17 529 U1.

[0005] Furthermore, there are various designs of ball-type tow hitches: In Europe, a ball diameter of 50 mm is common. US ball-type tow hitches typically have a ball diameter of 2 inches and are therefore slightly larger than the European version. Electric cars are often not designed or approved for towing. To still be able to attach a load carrier to the rear of the vehicle, some ball-type tow hitches are offered with side-protruding pins on the ball head, which makes towing impossible but still allows the attachment of load carriers. This can lead to a situation where a conventional load carrier is compatible with a standard vehicle but not with an electric car.

[0006] The invention therefore aims to provide a device that enables the simple mounting of various load carriers to a ball-type trailer hitch. Furthermore, the device should be compatible with different types of ball-type trailer hitches. In addition, the device should be easy to manufacture, lightweight, and unobtrusive when not attached to the trailer hitch without a load carrier.

[0007] Furthermore, the invention is based on the objective of providing a load carrier system that is universally applicable, easy to manufacture, and easy to assemble and disassemble.

[0008] The problems are solved according to the invention by an adapter with the features of claim 1, a connection device with the features of claim 12, and by a load carrier system with the features of claim 16.

[0009] Advantageous embodiments and further developments of the invention are specified in the dependent claims.

[0010] An adapter according to the invention for mounting a load carrier on a ball-type trailer hitch comprises a base body with a bottom, a cover opposite the bottom, and at least one side wall connecting the bottom to the cover. In the intended arrangement on the ball-type trailer hitch, the adapter is preferably oriented such that the cover is located at the top and the bottom at the bottom of the adapter. In its intended use, the cover is thus preferably located above the bottom. The terms "top" and "bottom" are used accordingly in the following.

[0011] The at least one side wall can be arranged between the base and the lid. Preferably, the at least one side wall is bounded at the top by the lid. At the bottom, the at least one side wall can be bounded by the base. The base of the adapter according to the invention has a base opening for the passage of a shaft of the ball-type trailer hitch and a contact surface for the bearing of a ball-type trailer hitch. The contact surface is preferably arranged on the upper side of the base. The contact surface can be recessed into the base to center the ball-type trailer hitch. The base opening is preferably designed such that the shaft can be inserted laterally into the base opening.

[0012] The cover has a cover opening with a longitudinal axis, around which a first thread having a first thread diameter is arranged. This first thread is operatively connected to the cover, and a threaded stud for attaching the adapter to the ball hitch can be screwed into it. The first thread is preferably operatively connected to the cover in such a way that force transmission from the first thread to the cover is possible. The first thread is preferably designed as an M20x1.5 thread. The threaded stud can have an internal hexagon socket, in particular with a wrench size of 10 mm.

[0013] The adapter is preferably attached to the ball-type towbar by positioning the shaft of the ball-type towbar in the base opening so that the ball rests against the mounting surface. The ball, located above the shaft, can thus be positioned between the base and the cover. The threaded stud can then be screwed into the first thread until it rests against the ball. By further tightening the threaded stud, the adapter can be securely and positively locked onto the ball-type towbar.

[0014] The cover may have position markings, particularly in the form of lines arranged radially around the cover opening, to determine the tightening torque of the threaded stud. To determine a safe tightening torque, the threaded stud can be screwed into the first thread until resistance is felt. From this position, if the threaded stud is tightened further so that a lever extending radially from a tightening tool sweeps more than the angle between two successive position markings in the tightening direction, the adapter can be securely attached to the ball-type trailer coupling.

[0015] Due to the described features, the adapter can be designed to be particularly compact. This allows the adapter to enable the use of load carriers on vehicles such as all-terrain vehicles, where previously the use of load carriers on the trailer hitch was difficult or impossible due to space constraints.

[0016] Preferably, at least one side wall has means for attaching the load carrier.

[0017] The means for fastening the load carrier can be designed as at least one fastening hole or at least one slot, particularly a T-shaped one. The at least one fastening hole is preferably provided with an internal thread, especially preferably an M8 internal thread. The at least one T-shaped slot is preferably designed as an opening through the at least one side wall. Thus, a load carrier having a T-shaped fastening element, similar to a T-nut, can be arranged on the adapter by pushing the transverse part of the T-shaped fastening element through a transverse part of the T-shaped slot and then guiding the fastening element downwards in a longitudinal part of the T-shaped slot. Further securing is preferably not required.The at least one T-shaped slot is particularly suitable for attaching load carriers, such as loading aids, that are not used while driving. The at least one mounting hole is particularly suitable for attaching load carriers that are used while driving.

[0018] In a preferred embodiment of the invention, the base body has a first side wall, a second side wall, and a third side wall, wherein the second and third side walls are arranged opposite each other and each form a right angle with the first side wall. The side walls, the lid, and the base are preferably rectangular. This allows the base body to be designed as a hollow, cuboid body with one open side. The open side is preferably located opposite the first side wall. The opening in the base is preferably designed such that the shaft of the ball-type trailer hitch can be inserted into the opening from the open side. Preferably, the adapter is arranged on the ball-type trailer hitch such that the open side faces the direction of travel of the associated vehicle.For safety reasons, the radii of the adapter's outer edges are preferably at least 2.5 mm. The first distance between the second and third side walls, as well as the second distance between the first side wall and the open side, can each be 52 mm or more. This ensures that the adapter can be used on a ball-type trailer hitch with a ball diameter of 2 inches.

[0019] The first side wall can have six mounting holes, and the second and third side walls can each have four mounting holes and a T-shaped slot. The mounting holes are preferably arranged in two parallel rows, opposite each other in pairs. The T-shaped slots can be positioned at least partially between the two rows. This arrangement allows for great flexibility in attaching load carriers. The arrangement of the T-shaped slots on the second and third side walls preferably results in mounting means being provided laterally to the ball-type trailer coupling relative to the associated vehicle, which are particularly suitable for attaching loading aids.

[0020] The second and third side walls can each have a recess for pins attached to the ball head. This makes the adapter particularly suitable for electric cars where the pins are located on the ball-type trailer hitch. The recess can be designed so that the respective pin is positioned within it in such a way that force transmission between the ball head and the adapter is possible. This allows the adapter to be secured against rotation using the two recesses and the two pins.

[0021] Preferably, the lid, the base, and at least one side wall are bonded together using a material-bonded connection. This allows for particularly high stability of the adapter while maintaining a low weight.

[0022] In a preferred embodiment of the invention, the threaded pin has an annular protrusion on a lower end face. This increases the surface pressure between the threaded pin and the ball head, thereby improving the frictional connection. The annular protrusion can be easily produced by drilling a central hole in the lower end face.

[0023] Preferably, the first thread is arranged in a threaded bushing that is positively locked and / or frictionally locked and / or materially locked to the lid. The threaded bushing is preferably arranged in the lid opening. The threaded bushing can, in particular, protrude downwards from the lid. By providing the threaded bushing, the first thread can be manufactured separately from the rest of the adapter and adapted to the respective application.

[0024] According to the invention, a second thread with a second thread diameter is arranged along the longitudinal axis above the first thread, into which a threaded plug can be screwed to secure the threaded stud. The second thread diameter can be larger than the first thread diameter. Preferably, the second thread is an M24x1.5 thread. By screwing in the threaded plug, the threaded stud can be secured against unintentional loosening. The threaded plug can have two blind holes arranged eccentrically and parallel to the longitudinal axis, in which an assembly tool can be placed. This allows the threaded stud to be secured against theft.

[0025] Preferably, the second thread is arranged in the threaded bushing. This allows for a high rigidity in securing the threaded pin.

[0026] It is particularly advantageous for the first thread to be a right-hand thread and the second thread a left-hand thread. This allows the threaded stud and the threaded plug to lock against each other, thus increasing the locking effect.

[0027] A connection device according to the invention for a previously described adapter has a preferably cuboid-shaped housing comprising a first housing wall and a second housing wall opposite the first housing wall, wherein the first housing wall and the second housing wall are spaced apart from each other such that a receiving space is formed between the first housing wall and the second housing wall, the receiving space being open towards a top surface so that a connecting element of a load carrier can be arranged in the receiving space. A bottom surface opposite the top surface, as well as the left and right sides of the connection device arranged perpendicular to the first and second housing walls, are preferably closed in such a way that the connecting element can be supported thereon.By inserting the load carrier's connecting element into the connection device, the load carrier can be easily, quickly, and securely mounted to the adapter. Thus, by adding the connection device to the adapter, a particularly user-friendly system is provided.

[0028] The connection device can have at least one first through-hole in the first housing wall, the through-hole having a first longitudinal axis, for fastening the connection device to the adapter. Preferably, at least one second through-hole, also having a second longitudinal axis, is arranged in the second housing wall such that the second longitudinal axis is aligned with the first longitudinal axis. This allows access through the second through-hole to a screw located in the first through-hole for fastening the connection device to the adapter. To allow the screw to be replaced through the second through-hole, the diameter of the second through-hole is preferably larger than the diameter of the first through-hole.The at least one first through-hole can be conical so that a screw placed in it can be countersunk and does not protrude into the receiving space.

[0029] At one upper end of the connection device, the first housing wall can have a bolt hole for receiving a fastening bolt, and the second housing wall can have a recess opposite the bolt hole. This allows the load-bearing element to be additionally fixed to the connection device using a bolt.

[0030] In an advantageous embodiment of the adapter described above, a previously described connection device is arranged on the adapter. In particular, the load carrier and the adapter can be mounted separately from each other by using the connection device. This results in significant handling advantages, especially with regard to the weight of the load carrier, particularly during assembly and disassembly.

[0031] A load carrier system according to the invention for a motor vehicle has a previously described adapter.

[0032] An embodiment of the invention is explained with reference to the following figures. It shows: Fig. 1 a perspective view of an exemplary embodiment of an adapter, Fig. 2 a side view of the embodiment with section plane AA drawn in, Fig. 3 the in Fig. 2. Sectional view AA shown, Fig. 4 a perspective view of the embodiment with a first attachment part, Fig. 5 a partially cut-out side view of the in Fig. 4 arrangement shown, Fig. 6 a perspective view of the embodiment with a second attachment, Fig. 7 a side view of the in Fig. 6 arrangement shown with section plane BB drawn, Fig. 8 the in Fig. 7. Sectional view BB shown Fig. 9 a perspective view of the embodiment with an attached assembly tool, Fig. 10 a first perspective view of the in Fig. 9 assembly tools shown, Fig. 11 a second perspective view of the in Fig. 9 assembly tools shown, Fig. 12 a perspective view of the embodiment of the adapter with the connecting device attached to it, Fig. 13 a first side view of the in Fig. 12 shown compilation, Fig. 14 a second side view of the in Fig. 12 shown compilation with section plane EE drawn in, Fig. 15 the in Fig. 14 sectional view EE of the in Fig. 12 shown compilation.

[0033] The Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8 to Fig. Figure 9 shows different views of an exemplary embodiment. For the sake of clarity, not all reference numerals are used in every figure.

[0034] Fig. Figure 1 shows a perspective view of an adapter 10 for mounting a load carrier on a [unclear] in the Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. 8. The ball-head trailer coupling 12 is shown in dashed lines. The adapter 10 has a base body 14 with a bottom 16 and a cover 18 arranged opposite the bottom 16. Preferably, the base body 14 has a first side wall 20, a second side wall 22 and a third side wall 24 that connect the bottom 16 to the cover 18.

[0035] For example Fig. As shown in Figure 2, the adapter, in the intended arrangement on the ball-type trailer coupling 12, is preferably oriented such that the cover 18 is located at the top and the base 16 at the bottom of the adapter 10. In intended use, the cover 18 is thus preferably located above the base 16. The first side wall 20, the second side wall 22, and the third side wall 24 can be arranged between the base 16 and the cover 18. Preferably, the first side wall 20, the second side wall 22, and the third side wall 24 are bounded upwards by the cover 18. At the bottom, the first side wall 20, the second side wall 22, and the third side wall 24 can be bounded by the base 16.

[0036] The second side wall 22 and the third side wall 24 can be arranged opposite each other and each form a right angle with the first side wall 20. The first side wall 20, the second side wall 22, and the third side wall 24, as well as the cover 18 and the base 16, are preferably each rectangular. Thus, the base body 14 can be designed as an internally hollow, cuboid-shaped base body 14 with an open side 25. The open side 25 is preferably arranged opposite the first side wall 20. Preferably, the adapter 10 is arranged on the ball-head trailer coupling 12 such that the open side 25 faces into the Fig. 2 and Fig. 7 indicates the direction of travel 27 of an associated vehicle. For safety reasons, the radii of the outer edges 29 of the adapter 10 are preferably at least 2.5 mm. A first distance 31 between the second side wall 22 and the third side wall 24 ( Fig. 3) and a second distance (not shown) between the first side wall 20 and the open side 25 can each be 52 mm or more. Preferably, the lid 18, the base 16, the first side wall 20, the second side wall 22, and the third side wall 24 are bonded together.

[0037] As in the Fig. 3 and Fig. As shown in the sectional views 8, the base 16 of the adapter 10 has a base opening 26 for the passage of a shaft 28 of the ball-type trailer coupling 12 and a contact surface 30 for the bearing of a ball head 32 of the ball-type trailer coupling 12. The contact surface 30 is preferably arranged on a top surface 34 of the base 16. The contact surface 30 can be recessed into the base 16 to center the ball head 32. The base opening 26 is preferably designed such that the shaft 28 can be inserted laterally into the base opening 26 from the open side 25.

[0038] Especially in the Fig. 3 and Fig. Figure 8 shows that the cover 18 has a cover opening 36 with a longitudinal axis 38, wherein a first thread 42 having a first thread diameter 40 is arranged around the longitudinal axis 38. This first thread 42 is operatively connected to the cover 18, and a threaded stud 44 for attaching the adapter 10 to the ball-type trailer coupling 12 can be screwed into this threaded stud. The first thread 42 is preferably operatively connected to the cover 18 such that force transmission from the first thread 42 to the cover 18 is possible. The first thread 42 is preferably designed as an M20x1.5 thread. The threaded stud 44 can have an internal hexagon socket 46, in particular with a wrench size of 10 mm.

[0039] The functional connection between the first thread 42 and the cover 18 can be established by arranging the first thread 42 in a threaded bushing 47 which is connected to the cover 18. The threaded bushing 47 is preferably arranged in the cover opening 36. The threaded bushing 47 can, in particular, project downwards from the cover 18.

[0040] The adapter 10 is preferably attached to the ball-type trailer hitch 12 such that the shaft 28 is positioned in the base opening 26 so that the ball head 32 rests against the contact surface 30. The ball head 32, located above the shaft 28, can thus be positioned between the base 16 and the cover 18. The threaded pin 44 can then be screwed into the first thread 42 until it rests against the ball head 32. By further tightening the threaded pin 44, the adapter 10 can be securely and positively locked to the ball-type trailer hitch 12.

[0041] In particular the presentation in Fig. Figure 1 shows that the cover 18 can have position markings 48, in particular in the form of lines arranged radially around the cover opening 36, for determining the tightening torque of the threaded stud 44. To determine a safe tightening torque, the threaded stud 44 can be screwed into the first thread 42 until resistance is felt. If, starting from this position, the threaded stud 44 is tightened further so that a lever extending radially from a tightening tool sweeps more than the angle 50 formed between two successive position markings 48 in the tightening direction, the adapter 10 can be securely attached to the ball-type trailer coupling 12.

[0042] Especially from the presentation in Fig. Figure 3 shows that the threaded pin 44 can have an annular projection 51b on a lower end face 51a. This increases the surface pressure between the threaded pin 44 and the ball head 32, thus improving the frictional connection. The annular projection 44 can be easily produced by drilling a central bore 51c into the lower end face 51a.

[0043] Preferably the first side wall 20, the second side wall 22 and the third side wall 24 have means for fastening the load carrier (see in particular Fig. 1) The means for fastening the load carrier can be designed as at least one fastening bore 52 or at least one T-shaped slot 54. In particular, the first side wall 20 can have six fastening bores 52, and the second side wall 22 and the third side wall 24 can each have four fastening bores 52 and one T-shaped slot 54. The fastening bores 52 are preferably arranged in pairs opposite each other in two parallel rows. The T-shaped slots 54 can each be arranged at least partially between the two rows.

[0044] The mounting holes 52 are preferably provided with an M8 internal thread. The T-shaped slots 54 are preferably designed as openings through the second side wall 22 and the third side wall 24. Thus, a load carrier having a T-shaped fastening element, similar to a T-nut, can be arranged on the adapter 10 by pushing the transverse part of the T-shaped fastening element through a transverse part 56 of the T-shaped slot 54 and then guiding the fastening element downwards in a longitudinal part 58 of the T-shaped slot 54.

[0045] The Fig. 4 and Fig. Figure 5 shows the adapter 10 with a first attachment part 59a, shown with a dashed line, which is screwed to the first side wall 20. Fig. 6, Fig. 7 to Fig. Figure 8 shows the adapter 10 with a second attachment 59b (shown with dashed lines) that is screwed onto the second side wall 22. The first attachment 59a and the second attachment 59b can represent an interface or part of the load carrier.

[0046] As shown in the sectional views in the Fig. 3 and Fig. As shown in Figure 8, the second side wall 22 and the third side wall 24 can each have a recess 60 for pins 62 arranged on the ball head 32, as is the case, for example, with electric cars.

[0047] Along the longitudinal axis 38 above the first thread 42, a second thread 66 with a second thread diameter 64 is arranged around the longitudinal axis 38, into which a threaded plug 68 can be screwed to secure the threaded stud 44. Preferably, the second thread 66 is arranged in the threaded bushing 47. The second thread diameter 64 can be larger than the first thread diameter 40. Preferably, the second thread 66 is designed as an M24x1.5 thread. By screwing in the threaded plug 68, the threaded stud 44 can be secured against unintentional loosening. The threaded plug 68 can have two blind holes 70 arranged eccentrically and parallel to the longitudinal axis 38, in which an assembly tool 72 can be arranged. Fig. 1, Fig. 4 and Fig. The threaded plug 68 can be seen from above in figure 6. Fig. Figure 9 shows the adapter 10 with the mounting tool 72 attached to the threaded plug 68. In the Fig. 10 and Fig. Figure 11 shows the assembly tool 72 separately. It may have an inscription 74 indicating the change in the direction of rotation due to the left-hand thread.

[0048] The first thread 42 is preferably designed as a right-hand thread and the second thread 66 as a left-hand thread. The threaded pin 44 and the threaded plug 68 can thus mutually lock each other, thereby increasing the locking effect.

[0049] The Fig. 12, Fig. 13, Fig. 14 to Fig. Figure 15 shows the adapter 10 with a connecting device 76 arranged thereon. The connecting device 76 for the adapter 10 has a preferably cuboid-shaped housing, which has a first housing wall 78 and a second housing wall 80 opposite the first housing wall 78, wherein the first housing wall 78 and the second housing wall 80 are spaced apart from each other such that a receiving space 82 is formed between the first housing wall 78 and the second housing wall 80, wherein the receiving space 82 is open towards a top surface 84, so that a connecting element 86 of a load carrier can be arranged in the receiving space 82. A bottom surface 88 arranged opposite the top surface 84, as well as the left side 90 arranged perpendicular to the first housing wall 78 and the second housing wall 80, and in the Fig. 12, Fig. 13, Fig. 14 to Fig.The right side of the connection device 76 (not shown) is preferably closed in such a way that the connecting element 86 can be supported against it. By inserting the connecting element 86 of the load carrier into the connection device 76, the load carrier can be easily, quickly and securely mounted to the adapter 10.

[0050] The connecting device 76 can have several first through-holes 94 in the first housing wall 78, each having a first longitudinal axis 92, for fastening the connecting device 76 to the adapter 10. Preferably, a corresponding number of second through-holes 98, each having a second longitudinal axis 96, are arranged in the second housing wall 80 such that each of the second longitudinal axes 96 is aligned with one of the first longitudinal axes 92. This allows access through the second through-holes 98 to a screw 100, which is located in each of the first through-holes 94 for fastening the connecting device 76 to the adapter 10. To allow the screws 100 to be replaced through the second through-holes 98, the diameter 102 of the second through-holes 98 is preferably larger than the diameter 104 of the first through-holes 94.The first through holes 94 can be conical so that the screw 100 placed therein can be countersunk and does not protrude into the receiving space 82.

[0051] At an upper end of the connection device 76, the first housing wall 78 can have a bolt bore 108 for receiving a fastening bolt 110, and the second housing wall 80 can have a recess 112 arranged opposite the bolt bore 108. Reference symbol list 10 adapters 12 ball head trailer hitch 14 basic shapes 16 Floor 18 lids 20 first side wall 22 second side wall 24 third side wall 25 open page 26 Bottom opening 27 Direction of travel 28 shaft 29 outer edge 30 site area 31 first distance 32 ball head 34 Top 36 Lid opening 38 Longitudinal axis 40 first thread diameter 42 first thread 44 Threaded pin 46 Hex socket 47 Threaded bushing 48 position markers 50 angles 51a lower front 51b Emphasis 51c central bore 52 Mounting holes 54 slots 56 Cross section 58 Longitudinal section 59a first attachment 59b second attachment 60 recess 62-pin 64 second thread diameter 66 second thread 68 threaded plugs 70 Blind hole drilling 72 assembly tools 74 Inscription 76 Connection device 78 first case wall 80 second case wall 82 Recording Room 84 Top 86 Connecting element 88 Underside 90 left side 92 first longitudinal axis of bore 94 first through hole 96 second bore longitudinal axis 98 second through hole 100 screws 102 second through-hole diameter 104 first through-hole diameter 108 bolt holes 110 fastening bolts 112 Release

Claims

[1] Adapter (10) for mounting a load carrier on a ball-type trailer coupling (12) with the following features: • a base body (14) with a base (16), a lid (18) arranged opposite the base (16) and at least one side wall (20, 22, 24) connecting the base (16) to the lid (18), • wherein the base (16) has a base opening (26) for the passage of a shaft (28) of the ball-head trailer coupling (12) and a contact surface (30) for the contact of a ball head (32) of the ball-head trailer coupling (12), and wherein the cover (18) has a cover opening (36) with a longitudinal axis (38), wherein a first thread (42) having a first thread diameter (40) is arranged around the longitudinal axis (38), which is in operative connection with the cover (18) and into which a threaded stud (44) for fastening the adapter (10) to the ball-head trailer coupling (12) can be screwed, characterized by, that along the longitudinal axis (38) above the first thread (42) around the longitudinal axis (38) a second thread (66) having a second thread diameter (64) is arranged, into which a threaded plug (68) can be screwed to secure the threaded pin (44). [2] Adapter according to claim 1, characterized by , that at least one side wall (20, 22, 24) has means for attaching the load carrier. [3] Adapter according to claim 2, characterized by that the means for fastening the load carrier are designed as at least one fastening hole (52) or at least one, in particular T-shaped, slot (54). [4] Adapter according to any one of the preceding claims, characterized by, that the basic body (14) has a first side wall (20), a second side wall (22) and a third side wall (24), wherein the second side wall (22) and the third side wall (24) are arranged opposite each other and each form a right angle with the first side wall (20). [5] Adapter according to claim 4, characterized by , that the first side wall (20) has six fixing holes (52) and the second side wall (22) and the third side wall (24) each have four fixing holes (52) and a T-shaped slot (54). [6] Adapter according to one of claims 4 or 5, characterized by , that the second side wall (22) and the third side wall (24) each have a recess (60) for pins (62) arranged on the ball head (32). [7] Adapter according to any one of the preceding claims, characterized by, that the lid (18), the base (16) and the at least one side wall (20, 22, 24) are joined together in a materially bonded manner. [8] Adapter according to any one of the preceding claims, characterized by , that the threaded pin (44) has an annular protrusion (51b) on a lower end face (51a). [9] Adapter according to any one of the preceding claims, characterized by , that the first thread (42) is arranged in a threaded bushing (47) which is positively and / or frictionally and / or materially connected to the cover (18). [10] Adapter according to claim 9, characterized by , that the second thread (66) is arranged in the threaded bushing (47). [11] Adapter according to any one of the preceding claims, characterized by , that the first thread (42) is designed as a right-hand thread and the second thread (66) as a left-hand thread. [12] Connection device (76) for an adapter (10) according to one of the preceding claims, comprising a housing comprising a first housing wall (78) and a second housing wall (80) opposite the first housing wall (78), wherein the first housing wall (78) and the second housing wall (80) are spaced apart from each other such that a receiving space (82) is formed between the first housing wall (78) and the second housing wall (80), wherein the receiving space (82) is open towards a top (84) so ​​that a connecting element (86) of a load carrier can be arranged in the receiving space (82). [13] Connection device according to claim 12, characterized by, that in the first housing wall (78) at least one first through hole (94) having a first longitudinal axis (92) for fastening the connecting device (76) to the adapter (10) is arranged, and that in the second housing wall (80) at least one second through hole (98) having a second longitudinal axis (96) is arranged such that the second longitudinal axis (96) is aligned with the first longitudinal axis (92). [14] Connection device according to one of claims 12 to 13, characterized by , that at an upper end of the connection device (76) the first housing wall (78) has a bolt bore (108) for receiving a fastening bolt (110) and the second housing wall (80) has a recess (112) arranged opposite the bolt bore (108). [15] Adapter according to any one of claims 1 to 11, characterized by, that a connection device (76) according to one of claims 12 to 14 is arranged on the adapter (10). [16] Load carrier system for a motor vehicle with an adapter (10) according to one of claims 1 to 11 or according to claim 15.

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