The present invention relates to a method for continuous manufacture of profiledd sections.

In continuous casting according to prior-art technology, it is possible to manufacture elongate profiled sections in a variety of highly diversified cross-sectional configurations. However, it is only possible to produce profiled sections having either smooth side faces or side faces presenting ribbed structures extending in the longitudinal direction of the profiled section. It has not been possible to manufacture profiled sections having transversally extending ribs or profiled sections having parts projecting transversally from the sections. As one obvious example of the need for profiled sections of the latter kind may be mentioned various framework structures, such as the masts for radio and television broadcasting antennae. In this case, elongate profiled sections are manufactured, in which a number of holes are drilled, both holes formed at the section ends to allow the profiled sections to be interconnected into longer lengths by means of bolt joints, and equidistantly spaced holes intermediate the profiled section ends in order to thus, also by means bolt joints, attach transverse stays between the elongate profiled sections thus to build a mast. The boring of the lengthwise profiled sections and assembly of the latter and of the transverse stays is a time-consuming work requiring highly skilled personnel to mount the mast to ensure that the latter will be a safe construction. Interconnecting the lengthwise sections and transverse stays by welding

instead of be screwing also is a time-consuming operation.

The invention provides a method making it possible to produce profiled sections of considerably more varied types than has hitherto been possible, including profiled sections formed with transversally projecting profiled section parts. The characteristic features of the method appear from the appended claims 1 and 2.

The invention likewise concerns a device for performing the method for continuous manufacture of profiled sections. The features characterising this device appear from the appended claims 3 and 4.

The invention will be described in more detail in the following with reference to the accompanying drawings, wherein:

Fig. 1 is a longitudinal sectional view through one embodiment of the device in accordance with the invention,

Fig. 2 is another longitudinal sectional view through the device,

Fig. 3 is a view of the device as seen from above,

Fig. 4 illustrates the device on an enlarged scale in a sectional view taken on line 4-4 in Fig. 3,

Fig. 5 shows the device in accordance with a different embodiment thereof in a perspective view and on an enlarged scale.

A section-shaping tool 1 is provided with a passageway 2 into which is supplied a compound 3 in the form of plastically/thermally mouldable material, such as a heated metal, on which pressure is continuously exerted to urge the compound forwards in the direction of arrow 4 in Figs 1 and 2. The shaping tool 1 includes a die, which is arranged for rotable movement in the direction of arrow 6 while being mounted in bearing boxes 7 arranged on either side of the die 5. The die 5 rotates in abutment against stationary die 8 and on its peripheral

face 9 it is provided with equidistantly spaced recesses 10.

In accordance with the shown embodiment the shaping tool 1 has two outlet mouths allowing two parallell strings 11,12 of material to be continuously extruded between the rotating die 5 and the stationary die 8 while the material 3 is being pressed forward. Simultaneously with the advancement of the material and the rotation of the die 5 one recess 10 at a time is filled with material 3 the latter being integral with the lengthwise strings 11, 12, and forming equidistantly spaced transverse profiled section parts or stays 13.

In accordance with the embodiment chosen, the resultant composite profiled section thus will be given a ladder-like configuration wherein the lengthwise strings or profiled sections 11,12 and the transverse stays 13 together form one single, continuous piece. In this manner, sections of considerable length may be manufactured, the component parts of which need no longer, contrary to what has hitherto been required, receive further treatment, for instance to have holes bored therein, nor is it necessary to assemble the parts by means of bolt joints or in any other way. The transverse stays 13 may be configured in various ways by changing the shape of the recesses 10 and the stays need not extend at right angles to the lengthwise profiled section 11,12 in the manner illustrated but could equally well extend obliquely at an angle suitable for the intended purpose. Fig. 5 illustrates an embodiment according to which the device comprises four dies 14,15,16 and 17. The dies are so positioned relatively to one another that the rotational axis 18,19,20 and 21 of each die is directed perpendicularly to the rotational axes of neighbouring dies. Owing to this arrangement it becomes possible to produce a finished framework construction 22 already during the continuos profiled-section shaping process

proper, as indicated in dash-and-dot lines. The entire construction is one integral piece, just like the profiled section in accordance with the earlier embodiment. From this example are easily understood the considerable time and cost savings that are obtained because the need for assembling and mounting of the profiled-section parts of the construction has been obviated.

The device according to the invention may be used to manufacture a large variety of different profiled sections in a variety of different materials. For use in the electric field, ladder shaped cables may be manufactured, within the aeroplane, train, boat and car industries lightweight aluminium profiled sections may be manufactured the strength of which does not depend entirely on the material but also on the fact that during the manufacture by means of rotation dies a rolling effect is achieved, i.e. a change of the material structure in the surface layer of the material while at the same time there is no need for drilling holes in the profiled sections, which has a weakening effect thereon. The device in accordance with the invention is also very well suited for producing profiled sections adapted for erection of various types of masts, for instance collision-safe poles for mounting of street lights and traffic lights which poles, upon impact, yield and bend instead of penetrating into the colliding vehicle. Also in a great variety of other situations it is possible to use profiled sections manufactured in accordance with the method and with the aid of the device in accordance with the invention.

Consequently, the invention is not limited to the embodiments described and illustrated herein but could be varied in many ways within the scope of the appended claims. Instead of manufacturing a profiled-section incorporating transversally projecting profiled section parts it is possible to provide the die 5 with recesses

of such a kind that the lengthwise profiled section 11 and 12 will have a rack-like configuration. The resultant rack will possess extremely high strength since its surface structure will differ from that of a rack having cogs cut therein.