Plug coupling with strain relief for a connecting cable

1. A strain relief arrangement ( 4 ) for a connecting cable ( 2 ), comprising:

a threaded pin ( 12 ), having clamping tongues ( 13 ) at a free end of the threaded pin ( 12 ), an enlarged diameter ( 10 , 11 ) on the threaded pin ( 12 ) for bearing against a surface of a carrier element ( 5 ), and an extension ( 15 ) for introducing and fastening the threaded pin in an opening ( 6 ) of the carrier element ( 5 ), and

a union nut ( 3 ) for screwing onto the threaded pin ( 12 ),

wherein the strain relief arrangement ( 4 ) has a passage bore ( 25 ) for the passage of the connecting cable ( 2 ),

wherein, by screwing of the union nut ( 3 ) onto the threaded pin ( 12 ), the clamping tongues ( 13 ) are caused to move radially inward and are pressed against an outer circumference of the connecting cable ( 2 ) in order to bring about the strain relief of the connecting cable ( 2 ),

wherein the extension ( 15 ) is of non-round or polygonal design with a radially larger region ( 16 ) and a radially smaller region ( 17 ), wherein the opening ( 6 ) of the carrier element ( 5 ) is geometrically complementary ( 7 , 8 ) to the non-round or polygonal extension ( 15 ), wherein the radially larger region ( 16 ) of the non-round or polygonal extension ( 15 ) includes a circumferential groove ( 20 ) adjacent to the enlarged diameter ( 10 , 11 ) and extending over a partial circumference of the polygonal extension ( 15 ), wherein an axial width of the circumferential groove ( 20 ) corresponds to a thickness of the carrier element ( 5 ) at the opening ( 6 ), and wherein a radial depth of the circumferential groove ( 20 ) corresponds to a radial dimension of the at least one radially smaller region ( 17 ) of the extension ( 15 ) in such a manner that the extension ( 15 ) is sized to be introduced into the complementary opening ( 6 ) of the carrier element ( 5 ) and to be fastened to the carrier element ( 5 ) by rotation in the complementary opening ( 6 ),

wherein a region ( 10 ) of the enlarged diameter ( 10 , 11 ) on the strain relief arrangement ( 4 ) is shaped as a circular flange ( 10 ), the diameter of which is larger than the greatest radial extent of the opening ( 6 ) of the carrier element ( 5 ), and wherein the circular flange ( 10 ) has a latching pin ( 19 ) facing the surface of the carrier element ( 5 ) and is latchable into at least one depression ( 9 ) in the surface of the carrier element ( 5 ).

2. The strain relief arrangement as claimed in claim 1 , wherein the radially larger region ( 16 ) of the extension ( 15 ) consists of two radially opposite circular portions ( 16 ) with the common center point on the longitudinal axis ( 26 ) of the bore ( 25 ) for the connecting cable ( 2 ), wherein the radially smaller region ( 17 ) of the extension ( 15 ) consists of parallel, radially opposite flattened portions ( 17 ), and wherein a respective circumferential groove ( 20 ) is formed in each radially larger region ( 16 ).

3. The strain relief arrangement as claimed in claim 1 , wherein the extension ( 15 ) to be introduced into the opening ( 6 ) of the carrier element ( 5 ) has a widened receptacle ( 24 ) for a plug contact connected to the connecting cable ( 2 ).

4. The strain relief arrangement as claimed in claim 1 , wherein a depression ( 6 ) designed as a latching bore is arranged adjacent to the circumference of the opening ( 6 ) in the carrier element ( 5 ), said depression serving for the latching of the strain relief arrangement ( 4 ) to a carrier element ( 5 ) of smaller thickness and for the latching of the strain relief arrangement ( 4 ) to a carrier element ( 5 ) of greater thickness by means of the latching pin ( 19 ) in different positions.

5. A system comprising and operating unit ( 1 ), an electronically controlled air suspension system, and a strain relief arrangement ( 4 ) as claimed in claim 1 , wherein the operating unit is electrically connected releasably to the electronically controlled air suspension system via the strain relief arrangement ( 4 ) and the strain relief arrangement is coupled to a connecting cable ( 2 ).

6. A strain relief arrangement ( 4 ) for a connecting cable ( 2 ), comprising:

a threaded pin ( 12 ), having clamping tongues ( 13 ) at a free end of the threaded pin ( 12 ), an enlarged diameter ( 10 , 11 ) on the threaded pin ( 12 ) for bearing against a surface of a carrier element ( 5 ), and an extension ( 15 ) for introducing and fastening the threaded pin in an opening ( 6 ) of the carrier element ( 5 ), and

a union nut ( 3 ) for screwing onto the threaded pin ( 12 ),

wherein the strain relief arrangement ( 4 ) has a passage bore ( 25 ) for the passage of the connecting cable ( 2 ),

wherein, by screwing of the union nut ( 3 ) onto the threaded pin ( 12 ), the clamping tongues ( 13 ) are caused to move radially inward and are pressed against an outer circumference of the connecting cable ( 2 ) in order to bring about the strain relief of the connecting cable ( 2 ),

wherein the extension ( 15 ) is of non-round or polygonal design with a radially larger region ( 16 ) and a radially smaller region ( 17 ), wherein the opening ( 6 ) of the carrier element ( 5 ) is geometrically complementary ( 7 , 8 ) to the non-round or polygonal extension ( 15 ), wherein the radially larger region ( 16 ) of the non-round or polygonal extension ( 15 ) includes a circumferential groove ( 20 ) adjacent to the enlarged diameter ( 10 , 11 ) and extending over a partial circumference of the polygonal extension ( 15 ), wherein an axial width of the circumferential groove ( 20 ) corresponds to a thickness of the carrier element ( 5 ) at the opening ( 6 ), and wherein a radial depth of the circumferential groove ( 20 ) corresponds to a radial dimension of the at least one radially smaller region ( 17 ) of the extension ( 15 ) in such a manner that the extension ( 15 ) is sized to be introduced into the complementary opening ( 6 ) of the carrier element ( 5 ) and to be fastened to the carrier element ( 5 ) by rotation in the complementary opening ( 6 ),

wherein the circumferential groove is a first circumferential groove, further comprising a second circumferential groove ( 22 ), the first and second circumferential grooves following each other in the circumferential direction and formed in two opposed radially larger regions ( 16 ) of the extension ( 15 ), wherein the first circumferential groove ( 20 ) has an axial width corresponding to a smaller thickness of a first carrier element ( 5 ), and wherein the second circumferential groove ( 22 ) has an axial width corresponding to a greater thickness of another carrier element ( 5 ).

7. The strain relief arrangement as claimed in claim 6 , wherein a respective run-on slope ( 21 , 23 ) is formed at one end of each of the first and second circumferential grooves ( 20 , 22 ).

8. The strain relief arrangement as claimed in claim 6 , wherein a base of the first and second circumferential grooves ( 20 , 22 ) runs from the opposite flattened portions as circular arcs ( 20 a , 22 a ) toward adjoining circular portions, and wherein tangents ( 20 b , 22 b ) extend adjoining the circular arcs toward the circular portions, the tangents acting as a rotary stop in a state, in which the strain relief arrangement ( 4 ) is inserted, rotated and latched in the opening ( 6 ) of the carrier element ( 5 ).

9. The strain relief arrangement as claimed in claim 6 , wherein the radially larger region ( 16 ) of the extension ( 15 ) consists of two radially opposite circular portions ( 16 ) with the common center point on the longitudinal axis ( 26 ) of the bore ( 25 ) for the connecting cable ( 2 ), wherein the radially smaller region ( 17 ) of the extension ( 15 ) consists of parallel, radially opposite flattened portions ( 17 ), and wherein a respective circumferential groove ( 20 ) is formed in each radially larger region ( 16 ).

10. The strain relief arrangement as claimed in claim 6 , wherein the extension ( 15 ) to be introduced into the opening ( 6 ) of the carrier element ( 5 ) has a widened receptacle ( 24 ) for a plug contact connected to the connecting cable ( 2 ).

11. A system comprising and operating unit ( 1 ), an electronically controlled air suspension system, and a strain relief arrangement ( 4 ) as claimed in claim 6 , wherein the operating unit is electrically connected releasably to the electronically controlled air suspension system via the strain relief arrangement ( 4 ) and the strain relief arrangement is coupled to a connecting cable ( 2 ).