Patent EA-001022-B1 (EA)
Title: Coupling purlin consisting of two or more wooden beams adjoining and overlapping each other longitudinally, as well as fastening element for joining two overlapping end areas of wooden beams for use as a coupling purlin
Inventor: MATTLE PAUL
IPC: E04B1/26
Filed: 1998-06-05
Abstract: 1. A coupling purlin comprising two or more wooden beams (2, 3) adjoining overlappingly in longitudinal direction, the overlapping end regions being joined to each other by fastening elements, characterized in that the overlapping end regions of the wooden beams (2, 3) are joined together by screws (5), which are driven in such that they are oriented at least approximately in a plane running transversely relative to the adjoining surfaces (6, 7) of the wooden beams (2, 3) and are disposed at an acute angle or at right angles to these surfaces (6, 7). 2. A coupling purlin according to claim 1, characterized in that screws (5) are inserted in pairs, the screws being disposed parallel to each other with space therebetween. 3. A coupling purlin according to claim 1, characterized in that screws (5) are inserted in pairs, the screws being oriented in crosswise directions and disposed in successive planes having a small space therebetween. 4. A coupling purlin according to one of claims 1 to 3, characterized in that the screws (5) inserted in pairs while having crosswise orientation if applicable and being disposed successively with space therebetween are screwed in starting from the same external surface (9, 10) of a wooden beam (2, 3). 5. A coupling purlin according to one of claims 1 to 3, characterized in that each of the screws (5) inserted in pairs while having crosswise orientation if applicable and being disposed successively with space therebetween is screwed in starting from diametrically opposite external surfaces (9, 10) of the two wooden beams (2, 3) to be joined to one another. 6. A coupling purlin according to one of claims 1 to 5, characterized in that one or more pairs (8) of screws (5) inserted in crosswise orientation if applicable is or are inserted at a short distance from the respective end of a wooden beam (2, 3). 7. A coupling purlin according to one of claims 1 to 6, characterized in that one or more of the screws (5) driven in at an acute angle projects or project beyond the lower surface (12) of the wooden beams (2, 3) to be joined to each other and engages or engage with its end or their ends in a wooden load-bearing member (4) disposed thereunder. 8. A coupling purlin according to claim 7, characterized in that there is or are inserted, parallel to the facing surfaces (6, 7) of the two overlapping end regions of the wooden beams (2, 3), in the region of intersection between a coupling purlin (1) and a wooden load-bearing member (4) disposed thereunder, one or more screws in addition to the screws (5) inserted at an acute angle or in lieu thereof. 9. A coupling purlin according to claim 8, characterized in that the additional screw(s) is or are associated with the overlapping end region of the wooden beam (2, 3) which is higher in the direction of the roof slope. 10. A coupling purlin according to one of claims 1 to 8, characterized in that the screws (5) inserted at an acute angle relative to the surface (6, 7) of the wooden beams (2, 3) include an angle (α) of approximately 45 degree  with the surface, so that the screws (5) disposed successively while having crosswise orientation with space therebetween are disposed at right angles to each other. 11. A fastening element for joining two overlapping end regions of wooden beams for insertion in a coupling purlin according to claims 1 to 10, characterized by a screw (5) with a shank, at one end of which there is formed a penetrating point (18) or a boring point or a boring part and at the other end of which there is formed a screw head (16) with an internal drive (15), wherein the shank is provided at least at its two end regions with a threaded portion (13, 14) and two threaded portions (13, 14) of different diameter (D1, D2) but the same thread pitch are disposed successively, and wherein the portion (14) with the larger diameter (D2) has a minor diameter (D3) corresponding at least approximately to the major diameter (D1) of the portion (13) with the smaller diameter (D1).