SK156599A3 - COUPLING PURLIN CONSISTING OF TWO OR MORE WOODEN BEAMS ADJOININGì (54) AND OVERLAPPING EACH OTHER LONGITUDINALLY, AS WELL A - Google Patents

Abstract

The invention relates to a coupling purlin (1) for which two wooden beams (2, 3) adjoining and overlapping each other longitudinally are connected to each other by fastening elements. The overlapping end areas of the wooden beams (2, 3) are connected by means of screws (5) which are positioned at an acute angle in relation to the adjoining surfaces (6, 7) of the wooden beams (2, 3). Said screws (5) are screwed in along a plane situated at a right angle to the surfaces (6, 7).

Description

An associated purlin consisting of two or more longitudinally overlapping and connected timber beams as well as a fastening means for joining the two mutually overlapping ends of the timber beams to be used in the associated purlin.

Technical field

The invention relates to an associated purlin consisting of two or more longitudinally overlapping and interconnected timber beams, the overlapping ends being connected by means of fastening means. Further, the invention relates to a fastening means for connecting two overlapping ends of wooden beams to be used in a composite prison.

BACKGROUND OF THE INVENTION

The associated purlins, or so-called rafter purlins, are made up of single-field beams, which above the supports, e.g. roof trusses, by means of nails or pins of a flexurally rigid joint to form continuous beams. The individual beams formed from the timber beams are disposed in fields offset by the width of the beam and overlap in the region of the underlying supports, respectively. roof trusses. Since a flexurally rigid connection is required between the overlapping ends, bolts are normally not permissible as fasteners because of their high flexibility. In this context, it has already been proposed to use recesses on adjacent surfaces of the overlapping ends of the wooden beams, whereby recesses are inserted as connecting means to engage shear forces between the two mutually overlapping ends of the wooden beams. By means of additional bolts that extend over the ends of the timber beams and through the catches, the two overlapping areas of the timber beams are held together. When using such fastening means, in particular, shear and bending stresses arise. An appropriate dimensioning of the fastening means used is therefore also necessary.

FR 865.513 A discloses the joining of timber elements using acute angle screws to adjacent surfaces of the timber beams, always screwed at acute angles to the timber beam fibers, so that additional stresses on the timber joints result in additional screw forces pulling and pulling out.

The embodiment of EP 0 448 915 A discloses a method of forming a roof insulation, as well as a screw suitable for carrying out this method. In order not to burden the insulating interlayer, the timber beams and the underlying timber structure are held at a distance from each other. The screws used mainly act as a spacer between two wooden beams.

In the known fastener of the flat elements (DD 236 563 A1), a cylindrical bolt is used which has two thread sections with different diameters at the ends. Such a fastener must be inserted into the pre-drilled hole, and is intended primarily to interconnect the structural elements and connections in one node.

It is an object of the present invention to provide an associated purlin described in the introduction, as well as a fastening means for joining wooden beams into a single purlin purl. allowing significantly improved interconnection of the overlapping ends of wooden beams.

SUMMARY OF THE INVENTION

In the present invention, in a composite prison, this problem has been solved by connecting the overlapping ends of the timber beams together by means of screws which are located in a plane lying at least approximately perpendicular to the adjacent timber beam surfaces and screwed at acute or right angles to these surfaces.

By means of these measures according to the invention, fastening means are used.

bolt shape stressed by a combination of tension and pressure, the forces being transmitted through the thread of the bolts. No such preparatory work is necessary for such a combined prison, since the screwing of screws which lie at an acute angle to the adjacent surfaces of the wooden beams can be carried out directly on site. In such a procedure, there is practically no bending and shearing stress, but only the tension and compression. This is due to the use of screws as fastening means, but also as a result of a special method of screwing in a plane perpendicular to the surface. Sharp angle screwing is very effective. In addition, as a rule, the timber beams can be fastened and, in particular, securely to each other, since pre-drilling of the holes is not necessary for such screws.

An even better embodiment is achieved when screws are used in pairs, parallel to each other or in pairs,

-3directions, and which lie in planes with a small spacing between them. This creates an optimal connection between the overlapping ends of the timber beams, whereby the tensile and compressive forces are transmitted to both timber beams equally.

In such a variant, it is proposed that the pairs of screws that possibly cross and are spaced apart are screwed from the same surface of the wooden beam lying on the outside. In this case, one screw at right angles or obliquely upwards and one screw at right angles or obliquely downwards is screwed in, which is the easiest solution for handling. In this way, the joining of the wooden beams to the associated prison can always be carried out from the same side.

However, there is also the possibility that one of a pair of possibly intersecting screws, spaced apart from each other, can be screwed from the facing, on the outside of the lying surface, of the two wooden beams joined together. Such an embodiment may be advantageous for a certain load condition and a certain type of screws used.

In this context, it is also possible to use one or more pairs of optionally intersecting screws located at a small distance from the respective end of the timber beam. Preferably, such an embodiment is used, in particular, for the large cross-sections of the combined prisons and the long overlapping ends of the wooden beams. In this case, a plurality of connecting sections are used on the longer length of the mutually overlapping ends.

By using screws as fastening means, many more possibilities can be created with the present invention. One embodiment is that one or more of the bolts, screwed at an acute angle, extend beyond the bottom surface of the joining timber beams and penetrate at their ends into the underlying timber beam. By means of the invention, it is possible not only to optimally connect the overlapping ends of the wooden beams to one another, but it is also possible to connect an associated purlin made of wooden beams to the underlying wooden beam. Just if the individual timber beams of the composite prisons do not have too large spans, it may be sufficient, in certain circumstances, for the two overlapping ends of the timber beams to be joined together in virtually one working step and at the same time it. In this case, it is always possible to use additional screws in the overlapping ends of the timber beams to connect them together.

When attaching an associated purlin to a wooden beam below it, it may be advantageous to use one or more screws in the area of the intersection of the associated purlin and the wooden beam below it, in addition to the acute angle screws. screws located parallel to the adjacent surfaces of the two overlapping ends of the wooden beams. Screws placed parallel to adjacent surfaces practically only serve to attach the composite purlin to the timber beam, and it is particularly important that the composite purlin, which lies on the timber girder rotated according to the roof pitch, does not tilt. It is therefore necessary to press the associated purlins properly against the wooden beam.

In this context, it is advantageous if the additional screws are assigned to the overlapping end of the wooden beam which lies on the upper side in the roof pitch. This provides a more effective anti-torsion measure, since the fastening takes place in the upper section with respect to the roof slope, and the lower section of the associated purlin with respect to the roof slope forms an additional support, thereby creating a corresponding arm of the internal forces. As a result, only a relatively small force is required by means of the screw or screws used to prevent the associated purlin from tilting.

The optimum connection of the overlapping ends of the timber beams to form an associated purlin is achieved if the bolts lying at an acute angle to the surface of the timber beams are clamped at an angle of approximately 45 ° so that the intersecting screws spaced apart together right angle. This achieves a uniform distribution of forces on both ends of the timber beams, whereby the two screws of the respective pair are stressed in the same way on tension and compression.

The fastening means according to the invention, for connecting two overlapping ends of wooden beams used in the associated purlin, consists of a screw with a thread section at least at both ends, with sections of different diameter lying side by side having the same thread pitch, and wherein the larger diameter section has a core diameter of at least approximately the outer diameter of the thread of the smaller diameter section. By this measure according to the invention it is achieved that the adjacent, overlapping ends of the wooden beams are joined in a side-by-side position, without having to press against each other or even push each other off with a corresponding force. Thus, there is the same thread pitch, so that for two thread sections with different diameters, the thread sections already made in the wooden beam are not destroyed, but are eventually only enlarged in diameter. This is why it is also possible to make optimum use of tensile and compressive stresses for associated prisons.

A particularly advantageous measure with regard to the design of the screw and its use in wood is to align the diameters of both thread sections. In this case, there are no too high forming requirements for the production of such screws. When screwing such screws into the wood, it has proven advantageous that the cross-section core that follows the smaller diameter section practically compresses the finished thread, so that only the threads into the wood have to be extruded and not the entire cross-section with a larger diameter. A larger diameter thread is formed in the cross-section and, in this area in particular, a greater compression of the wood around the screw takes place. Cracking of the ends of the timber beams is prevented by pre-screwing the thread section with a smaller diameter. Naturally, it is also possible in this way to place such screws without pre-drilling the hole so that one work step can be omitted.

It is advantageous to provide a recessed portion at the end of the larger diameter section to receive the screwing tool. In this way, the necessary torque can be transmitted, and nevertheless the recessed portion for receiving the tool can be embedded in the outer surface of the wooden beam.

These measures facilitate the recess of the screw head. In addition, the last threads in the timber beam are compressed, thereby additionally compressing the wood in this area.

in

Further features and specific advantages of the invention will be explained in greater detail below with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1 is a cross-sectional view of the associated purlin in the region of the intermediate fastener;

In FIG. 2 is a view of a screw inserted as a fastener;

In FIG. 3 shows an associated purlin of two overlapping and interconnected timber beams lying on a wooden beam, whereby the timber beams are joined together by screws;

In FIG. 4 shows the same illustration as FIG. 3, but the connection between the associated purlin and the wooden beam is schematically illustrated;

In FIG. 5 is a cross-sectional view of an associated purlin connected in a prior art manner;

FIG. 6 is an oblique view of the associated purlin together with a wooden beam underneath, showing the joining of the timber beams of the associated purlin and the connection of the associated purlin to the wooden girder;

In FIG. 7 shows another embodiment of an associated purlin consisting of two overlapping and interconnected timber beams lying on a timber beam, whereby the timber beams are joined together by screws;

In FIG. 8 shows the same illustration as FIG. 7, but a schematic representation of the prior art joining of wooden beams by means of nails.

DETAILED DESCRIPTION OF THE INVENTION

In the associated purlin 1, two timber beams 2 and 3 overlapping in the longitudinal direction and connected to each other by means of fastening means are connected together. The associated purlins 1 are then laid on suitable supports or on wooden beams 4, which are either horizontally positioned or run at a slope corresponding to the roof slope. The following description refers to two wooden beams 2 and 3 which are connected to each other and form an associated purlin. However, it would also be possible within the scope of the invention to use more than two overlapping and interconnected wooden beams, for example the ends of the wooden beams being connected alternately from one side to the other. In this case, it would also be possible that after the two wooden beams overlapping together, the next wooden beam is joined and the overlapping area is reconnected to the next subsequent wooden beam. In this case, only the immediately adjacent, overlapping ends of two wooden beams would be connected to each other.

The interconnection is made by means of fastening means in the form of screws 5, which are placed at an acute angle to the adjacent surfaces 6, 7 of the wooden beams 2, 3 and are screwed so that they lie in a plane which extends at least approximately perpendicularly to these surfaces 6, 7 .

As can be seen in particular from FIG. 1 and 3, such bolts are used in pairs and are located in mutually intersecting directions and lie in planes with a small spacing between them. In this case, it is possible that only one pair of such screws 5 is disposed at both ends of the wooden beams 2 and 3. Depending on the forces to be transmitted, it may also be necessary to use two such pairs 8 of the screws 5 as shown in FIG. 3 - or more than two such pairs of 8 screws 5. In the mold

FIG. 1, one screw 5 is screwed in each of the pairs, which are located in mutually intersecting directions with a small spacing from each other, facing away from each other, the outer surfaces 9 and 10 of the two wooden beams 2, 3 connected to one another. screws that cross each other in pairs spaced apart screw the same outer surface 9 or 10 of the wooden beams 2 or 3 from the same outer surface.

The screw-in angle of the screws 5 is selected according to the respective load cases, but a particularly advantageous embodiment has been shown in which the screws 5 which are inclined at an acute angle to the surfaces 6, 7 of the wooden beams 2, 3 45 °. In this case, the screws 5, which intersect in pairs spaced apart, are positioned approximately at right angles to each other, whereby the tensile and compressive forces are transmitted to both wooden beams 2, 3 equally and the load is applied to the whole height of the wooden beams 2, third

In this context, it should be noted that it is not absolutely necessary that the screws 5 be screwed from the surfaces 9 and 10 of the wooden beams 2, 3. It is also possible to place these screws on the upper side 11 or the lower side 12 of the associated purlin. it must select an area which is relatively far outside in order to engage both wooden beams 2, 3 when screwed at acute angles.

The screw 5 used as a fastener is shown in FIG. 2 by way of example of one possible embodiment. In this screw 5, thread sections 13 and 14 are used at least at both ends of the shank, which have different diameters D1 or D2, but the same thread pitch. The larger diameter section D2 has a core diameter D3 that corresponds at least approximately to the external diameter of the thread D1 of the section 13. At the end of the larger diameter section D2 is a recessed portion 15 for receiving a screwing tool. Forming the screwdriver tool retaining part can also be done in a different way. In the embodiment shown, a cylindrical head 16 of the screw 16 is located at the end with the recessed part for receiving the tool 15, which is enlarged compared to a thread section with a diameter D4. The transition 17 between the thread section 14 and the screw head 16 is configured as a conical extension. In this way, the possibility of countersinking the screw head 16 is achieved in a simple manner, without causing too great a widening of the threading hole and thereby breaking the area of the wooden beams 2, 3.

Within the scope of the invention it is quite possible to use screws 5 with other configurations. It is only necessary to ensure that the screw 5 at both ends of the shaft has a thread section

Such that there is a corresponding number of turns in each of the interconnected wooden beams 2, 3 so that the tensile and compressive forces can be transmitted. In this case, it is also possible for the two thread sections to be coordinated with one another, i. despite the existence of a possible threadless portion of the shaft between the thread sections, they should have the same thread pitch. But it is also possible t

arrangement of one thread section continuously over the entire length of the screw 5.

At the end of the screw 5, the tip 18 is similar to the tip of a wood screw. Within the scope of the invention, it is also possible to use a drill-like tip or a suitable drill part in order not only to extend the timber beams to accommodate the screw 5, but also to process the chips to create a corresponding screw location.

5. In this case, the threads separate when the screw 5 is screwed in, thereby reducing the risk of cracking in the present case.

Referring to FIG. 4, it can be seen that, in addition to the connection between the individual timber beams 2, 3, which form the associated purlin 1, it is also possible to provide a connection between the associated purlin 1 and the wooden beam located below it. For this purpose, the bolts 5 which are screwed in at an acute angle are fastened by means of the ends of the wooden beams 2, 3 over the lower surface 12 of the two overlapping ends of the wooden beams. In this connection, it is also possible that, in the area of intersection between the associated purlin 1 and the timber beam 4, one or more screws parallel to the adjacent surfaces 6, 7 are used instead of or together with the acute angle screws 5. Such additional screws are preferably used at the overlapping end of the wooden beam 2, which lies at the top in the roof slope direction. This prevents the collapse of the associated prisons sufficiently.

In FIG. Figures 5 and 6 illustrate a method of joining the overlapping ends of wooden beams to form associated prisons and connecting the associated prisons to the underlying wooden beams. In order to connect the two wooden beams 2 and 3, recesses 19 had to be formed on both adjacent surfaces 6 and 7 in order to insert a catch 20 which then transferred the necessary shear and bending stresses. By means of additional bolts 21 passing through the timber beams 2 and 3, the two timber beams 2 and 3 were then interacted with. To connect the associated purlin 1 to the underlying wooden beam 4, corner connectors 22 are generally used.

- 9 made of metal sheets which are fastened to the associated purlin I as well as to the wooden beam 4 by means of screws.

In the embodiment of FIG. 7 and 8, screws 5 are used in pairs which are spaced parallel to each other with a small spacing between them. In this case, it is possible that only one pair of such bolts 5 is provided at both ends of the timber beams 2 and 3. Depending on the magnitude of the forces transmitted, it may be necessary to place two or more such pairs of bolts 5. The bolts 5 spaced apart they can screw from the facing, outer surfaces 9 and 10 of the two wooden beams 2, 3 which are connected to each other. 1, it is also possible for screws which are arranged parallel to each other to be screwed from the same outer surface 9 or K) of one of the wooden beams 2 or 3.

FIG. 8 shows how the joining of the overlapping ends of wooden beams has been relatively laboriously done so far to form associated prisons. In order to join the two wooden beams 2 and 3, a large number of nails 23 had to be hammered on both adjacent surfaces 6 and 7, but they could only transfer the shear and bending stresses.

Smooth nails may be used in associated prisons. As the roof slope is constantly subject to pulling out, openings must not be pre-drilled using smooth nails. For larger loads, special nails (threaded nails, knurled nails) can be used, which can be driven by a compressed air-driven nailing machine up to a diameter of 5 mm and a total length of 160 mm. Nails with larger diameters or longer nails must be driven in by hand, and holes must not be pre-drilled. These works are costly and possibly dangerous, as they generally have to be carried out at high altitude on site.

Obviously, the described measures will substantially improve the interconnection of wooden beams to the associated prisons and also between the associated prisons and the wooden beams. Not only the connection itself, but also the handling and especially the on-site handling will be improved, since the timber beams do not have to make precise recesses and no holes need to be pre-drilled.

-10Patent Claims

Claims (11)

An associated purlin of two or more longitudinally overlapping and interconnected wooden beams (2, 3), wherein the overlapping ends are interconnected by means of fastening means, characterized in that the overlapping ends of the wooden beams (2, 3) are connected by means of screws (5) which are located in a plane which lies at least approximately perpendicular to the adjacent surfaces (6, 7) of the wooden beams (2, 3) and are screwed in a plane which is placed at a sharp or right angle to these surfaces (6, 7). Compound purlin according to claim 1, characterized in that pairs of screws (5) are used, which are located parallel to each other with a small spacing between them. Composite purlin according to claim 1, characterized in that pairs of screws (5) are used, which are located in mutually intersecting directions and lie in planes with a small spacing between them. Compound purlin according to one of Claims 1 to 3, characterized in that the pairs of screws (5), which may be crossed and spaced apart, are screwed together from the same external surface (9, 10). ), one of the wooden beams (2, 3). Composite purlin according to one of Claims 1 to 3, characterized in that each of the pair of screws (5), which optionally cross and are spaced apart, is screwed from a mutually spaced apart outer surface (9). , 10), the two interconnected wooden beams (2, 3). Compound purlin according to one of Claims 1 to 5, characterized in that one or more pairs (8) of screws (5), which optionally cross and are used, are used. - 11 located a short distance from the respective end of one of the wooden beams (2, 3). Compound purlin according to one of Claims 1 to 6, characterized in that one or more of the bolts (5), at an acute angle, of the screwed-in screws (5) extend over the surface (12) lying on the underside of the two wooden beams (2, 3) , and it is fastened with its ends to the underlying wooden beam (4). Compound purlin according to claim 7, characterized in that, in addition to the bolts (5) which are positioned at an acute angle or instead of them, one is used in the region of the interconnected purlin (1) and the underlying wooden beam (4). or a plurality of screws which are arranged parallel to the adjacent surfaces (6, 7) of the two overlapping ends of the wooden beams (2, 3). Composite purlin according to claim 8, characterized in that the additional bolt or bolts are associated with the overlapping end of the wooden beam (2, 3) lying on top of the roof slope. Compound purlin according to one of Claims 1 to 8, characterized in that the screws (5), which are positioned at an acute angle to the surface (6, 7) of the wooden beams (2, 3), form an angle (α) of each other approximately equal to 45 °, so that the screws (5) that cross each other and are spaced apart are perpendicular to each other. Fastening means for connecting the two overlapping ends of the wooden beams of the associated purlin according to claims 1 to 10, characterized in that the screw (5) has a spike-like shaft (18) or a drill-like tip or a suitable drill part at one end and a screw head (16) with a recessed part for receiving the tool (15) at the other end, the shank having at least both ends a thread section (13, 14) followed by two sections (13, 14) with different diameters (D1) , D2) having the same thread pitch, wherein the larger diameter section (14) has a core diameter (D3), - 12 which corresponds at least approximately to the external diameter of the thread (D1) of the section (13) of the smaller diameter (D1).