A coupling device for quick mounting and demounting an integrated light source, comprising two tubular intermediate elements (A, B) having mutually matching cross-sections, each element (A, B) having a first ending and a second ending and being telescopically connectable with each other by inserting their first endings one into the other, each intermediate element (A, B) consisting of at least two tubular members (A-a, A-b; B-a, B-b) having different cross-sections of close dimensions, the members (A-a; B-a) of the intermediate elements (A, B) having bigger cross-sections and the members (A-b; B-b) of the intermediate elements (A, B) having smaller cross-sections, and the element (A) being telescopically connectable by its smaller member (A-b) with a socket (C) comprising electrical connections while the element (B) is telescopically connectable by its bigger member (B-a) with the light source (D). At least one line enabling electrical current transmission is run inside both intermediate elements (A, B) in a tight manner, and in that all the connections, both of the intermediate elements (A, B) with each other and of the intermediate elements (A, B) with respectively the socket (C) and the light source (D), ensure electrical current transmission from the socket (C) to the light source (D).