Abstract:
A composite profile comprising: (1) an extruded metal alloy carrier profile comprising a rail head having a longitudinal axis B, the rail head comprises a surface and two longitudinal edges extending parallel to the longitudinal axis B and (2) a metal channel shaped profile strip comprising a base portion spanning the surface of the rail head and parallel side legs which lie on the longitudinal edges of the head rail, an insert rod is provided on the parallel side legs which lie on the longitudinal edges of the head rail and engage in lateral slots provided in the two longitudinal edges of the rail head, wherein the profile strip is attached to the carrier profile under mechanical pretension by way of a weld scan.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related to U.S. application Ser. No. 11/711,397 filed Feb. 27, 2007, now U.S. Pat. No. 7,712,591, and U.S. application Ser. No. 11/815,018 filed Jul. 30, 2007. 
     BACKGROUND OF THE INVENTION 
     The invention concerns a composite profile with a rail-like carrier body extrusion-moulded from alloy material, and spanning its head surface a profile strip of a harder metal. The invention also concerns a method for production of such a composite profile. 
     DE 24 32 541 A1 describes a method for production of conductor rails from a carrier profile and at least one support, forming at least part of the surface of the carrier profile serving as the conductor rail, of a profile strip of another metal as a cover profile of higher abrasion resistance. During the extrusion moulding process the carrier profile is created from a block by means of extrusion through a moulding cross-section of an extrusion die and at the same time the profile strip runs parallel to the die longitudinal axis through the die opening or moulding cross-section. During the extrusion process, an internal metallic connection is formed between the two profile components. For example, on use of the conductor rail for electrification of rail vehicles, in cases of particularly high load, despite the inner metallic connection, in the long term the profile strip detaches from its carrier profile of alloy. 
     DE 44 10 688 A1 discloses a composite profile with a carrier profile of alloy and connected with this a profile strip. The latter spans the surface of a rail head of the carrier profile, is formed channel-like in cross section and in its side legs that protrude from the inner surface on the carrier body side at a distance from each other, has recesses which are embedded in the carrier body. These recesses delimit undercut cavities which are filled form-fit with the metallic material of the carrier body. This form-fit connection does not have the defects described in relation to the metallic connection. 
     A composite conductor rail element for power supply of a rail vehicle with a cover of a material of high mechanical resistance that is attached rigidly to a rod of electrically conductive material and forms the slide or contact surface for current pick-up of the vehicle, is disclosed in DE 25 46 026 A1. The cover is fixed to the conductive rod serving as the carrier in that the edges of the cover are clamped or crushed into the conductive rod. The result is at least one constriction, running in the longitudinal direction, in the cover which penetrates into the conductive rod. For clamping the edges of the cover, a groove is provided in the conductive rod which delimits a lip. The latter leads to the clamping of the cover on the conductive rod as soon as it is at least partly folded back and pressed against the edge of the cover. 
     Conductor rails on which their wearing components are attached to the conductive carrier profile by lateral through bolts or additional push elements have proved disadvantageous. Other known production methods can disadvantageously lead to corrugation on the surface of the cover profile which is caused by the stepped caulking or punching of the carrier profile. 
     In the knowledge of this prior art, the inventors have faced the task of largely improving the connection between the carrier profile and the profile strip while largely retaining the possibility of particularly economic production. 
     SUMMARY OF THE INVENTION 
     This object is achieved by providing a composite profile with a carrier profile extrusion-moulded from alloy material, and spanning its head surface a profile strip of a harder metal, characterised in that on the profile strip lying approximately on the head or surface of the carrier profile, on each long side parallel to its longitudinal axis (B) is attached an insert rod which on the other side engages in a lateral slot of the carrier profile, and is connected with its profile strip by way of a weld seam, wherein the channel-like profile strip with its anchor or insert rod is attached to the carrier profile under mechanical pretension. 
     According to the invention, on the profile strip or cover profile lying on the head or surface of the carrier profile and preferably made of special steel, on each long side is attached an anchor or insert rod parallel to the longitudinal axis of the profile strip, which anchor or rod on the other side engages in a side slot of the carrier profile and is connected with its profile strip by a weld seam; the channel-like profile strip with its anchor or profile rod is joined to the carrier profile generating a mechanical pretension which guarantees a permanently firm seat. The insert rod or profile is preferably made of the material of the profile strip, supplements the profile strip on both sides and thanks to the welded connection give secure protection for the internal surface of the conductive carrier profile. 
     With a profile strip formed channel-like that lies on the rail head of a rail-like carrier profile, it has proved favourable to connect the insert rod with a side leg of the profile strip, and on the other side insert this with at least one rod section protruding from that side leg in a correspondingly arranged slot of the carrier profile; that rod section runs at an angle to the cross-sectional axis of the carrier profile and thus generates the pretension according to the invention. 
     A channel-like insert rod of approximately V-shaped cross-section is preferred which lies with one channel leg on the inside of the side leg on the profile strip approximately axially parallel; the other channel leg is then directed towards the longitudinal axis of the profile strip and is mounted in a slot which is tilted at an angle to the cross-sectional longitudinal axis of the carrier profile. In this embodiment the cross-section of the slot in the rail head of the carrier profile is itself V-shaped, where the slot leg running in the side and longitudinal surface of the rail head is formed by a longitudinal recess. That angle preferably measures 60° to 70°, in particular 65°. 
     Another insert rod according to the invention is of angular cross-section and lies with one channel leg on the inside of the side leg; the other channel leg is tilted away from or alternatively towards the base plate of the profile strip. Here the angle which is delimited by the two channel legs should measure more than 90°, preferably around 110°. 
     The invention also extends to an insert rod with approximately semi-circular cross section which at the zenith of its curvature is welded with the outer face on the edge of the face of the side leg of the profile strip, so that the two insert rods of the profile strip are arranged on a common centre axis and open towards each other. This centre axis crosses the cross-sectional axis of the composite profile which in turn is parallel to its side surfaces. Also, the centre axes of the insert rods in each of the two long faces of the rail head determine the position of a bead, the cross-section of which is adapted to the form of the interior of the insert rod which is to be joined to it and which on both sides is limited by an insert slot for the free edge of the insert rod tilted to the centre axis. 
     The cross-section of another embodiment of the insert profile or rod according to the invention for the rail head comprises a quarter-circle section and a linear section, where the latter lies on the side leg of the profile strip on the inside and is welded to its face. These quarter-circle sections of the two insert rods can be oriented towards or away from the base plate of the profile strip. The slot of the rail head for the linear section of the insert rod should here contain a longitudinal recess in the long face of the rail head. Also, it must be ensured that the pairs of similarly shaped insert rods offer the same design in a mirror image. 
     In another feature of the invention an insert rod with a hook-like cross-section, with free hook section running at a distance from the side leg and directed towards the base plate of the profile strip, is welded at the other end to the face of the side leg. 
     It has also proved favourable to allow the slot-like recess in the rail head to be undercut by a longitudinal rib attached at a distance from the surface of the rail head and limited by the underside of the rail head. 
     In an alternative embodiment to the arrangement, described in more detail above, of the insert rod of hook-like cross section with free hook section running at a distance from the inner face of the side leg of the profile strip, said section points away from the base plate of the profile strip i.e. towards the foot area of the composite profile. This insert rod too is welded to the face of the side leg. 
     Another embodiment comprises an insert rod of stepped cross-section which at one end is welded to the inner face of the profile strip side leg and at the other end undercuts with its free hook end a peg strip in the long face of the rail head. 
     The scope of the invention also contains insert rods of linear cross-section, i.e. strip-like, which on the inside lie on the side legs of the profile strip and project over its side face with which they are connected by means of a through weld seam. This insert rod according to the invention is tilted towards the cross-sectional longitudinal axis of the composite profile at an angle of around 60° to 80°, preferably 70° to 75°. 
     In a further embodiment according to the invention, one of the two opposing surfaces of carrier profile and cover profile are curved in cross-section to its partner, which gives the required pretension. 
     The invention also comprises a method for production of a composite profile in which a carrier profile made of alloy material is extrusion-moulded with a head surface and insert slots accompanying this on both sides, where an insert rod in inserted in each slot and on each section of the insert rod protruding from the slot is laid a profile strip encompassing the head surface such that this cover profile has a pretension in relation to the carrier profile. 
     The insert rod is welded to the profile strip throughout. 
     First therefore the anchoring strips, anchor rods or insert rods are inserted or pressed or rolled into the alloy profile, in particular into a base Al profile, or before welding or afterwards fixedly rolled or pressed by residual deformation of the carrier profile. It must be ensured here that the pretension between the partners is created. With the help of a contact roller of large diameter, the special steel cover profile is pressed onto the alloy carrier profile and under this pretension the anchoring strips or insert rods are welded with the cover profile on the right and left simultaneously. 
     Also, the cover profile is preferably a special steel strip cut from a roll coil which is brought to the desired form by rolling or is used directly as a cut strip. The insert rod is a special steel strip—preferably of the same alloy as the cover profile—which advantageously is cut from the roll coil and brought to the desired form by rolling/trimming/flanging/edging. 
     In order to eliminate the defects cited initially, a continuously running composite profile—in the manner of extrusion moulding for the carrier profile and roll forming—is proposed over the entire profile length of cover profile and insert rods or anchoring profiles. The connection is achieved by continuous welding over the profile length. 
     The maximum possible width of the grinding surface is required with the possibility of coating from the side and mechanical anchoring which guarantees an anchoring of the then two residual grinding surfaces even when the wear profiles are fully worn. Also, a reduction in the installation height tolerance in comparison with known composite profiles is desired. Also desirable are local production facilities worldwide without having to re-equip a large alloy extrusion press. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages, features and details of the invention arise from the description below of preferred embodiment examples and with reference to the drawing which shows: 
         FIG. 1 ,  9  each a perspective view onto a section of a rail-like composite profile of two composite partners in the form of a rail profile with cover profile; 
         FIG. 2  the enlarged front view of the composite profile of  FIG. 1  with a component removed from the composite profile; 
         FIG. 3  the component removed from  FIG. 2  in the form of an insert rod, 
         FIG. 4  the front view of the cover profile used as a composite partner in  FIG. 1 ; 
         FIGS. 5 ,  6 ,  7  each a cross-section reduced in relation to  FIG. 2  through a composite profile of another design; 
         FIG. 8  two halves of the cross-sections of two different composite profiles; 
         FIG. 10  the cross-section through the composite profile in  FIG. 9 ; 
         FIG. 11  the front view of the cover profile used as a composite partner in  FIG. 9 ; 
         FIG. 12  the front views of an insert rod or profile for  FIG. 9 ,  10 ; 
         FIG. 13  the two composite partners of FIG.  10 —rail profile and cover profile—before assembly; 
         FIG. 14  the front view of a composite profile corresponding approximately to  FIG. 2  and comprising two composite partners; 
         FIG. 15  the composite profile of  FIG. 14  before assembly; 
         FIG. 16  two halves of the cross-sections of two different rail profiles, wherein the right figure half is allocated to  FIG. 17 ; 
         FIG. 17  the front view of the right rail profile of  FIG. 16  after assembly with the other composite partner; 
         FIG. 18 ,  19  each a front view of two further composite profiles before assembly; 
         FIG. 20 to 22  sketches of the production steps for the conductor rail; 
         FIG. 23  a sketch in oblique view of a section of a conductor rail during the production process; 
         FIG. 24  an enlarged fragment of the conductor rail in  FIGS. 3 ,  14 ; 
         FIG. 25  the fragment in  FIG. 24  on reduced scale during the production process. 
     
    
    
     DETAILED DESCRIPTION 
     A composite profile  10  of height h of here for example 105 mm and the maximum width b of 92 mm has in  FIG. 1  a rail-like carrier profile  12  with a rail foot  14  and an extrusion-like rail head  22  attached thereto by means of a rail web  20 . Two long edges  17  of height c of 10 mm limiting the foot surface  16  of the rail foot  14  run parallel to each other at a distance b 1  of here 80 mm. The dimensions given are established over approximately 70% of the present composite profile  10 ; the general dimension ranges are measured approximately as follows:
         Profile height h: 50 mm to 150 mm   Profile width b: 60 mm to 160 mm   Rail foot width b 1 : 30 mm to 130 mm.       

     Of these long edges  17 , the two roof surfaces  18  of the rail foot  14  which are slightly tilted towards each other are slightly tilted upwards to the cross-sectional centre axis Q crossing the longitudinal axis A of the composite profile  10  and transform into the axial rail web  20  of height h 1  of around 30 mm and thickness e of around 18 mm. At the upper end of the rail web  20  they are connected to the long edges  24  of the rail head  22 , the width b 2  of which measures around 78 mm and the external height n of which, of around 28 mm, determines the position of the rail head surface  28 . 
     From each of the long edges  24  of the rail head  22  in  FIG. 1 ,  2  starts a slot  30  which is tilted upwards to the cross-sectional longitudinal axis Q at an angle w of around 60° and of width a here 4 mm and depth t 18 mm, the lower wall face of which slot in  FIG. 2  transforms into a type of longitudinal rib  34  of the rail head  22 , the outside of which is formed by the under face  26 . Produced in the long edge  24 , forming a cross-sectional step  33 , is a longitudinal recess  32  as a physical extension of the slot  30  of V-shaped cross-section which also gives its width a. 
     This rail or carrier profile  12  of the composite profile  10  is formed from an alloy material in an extrusion die which is not shown in the drawing for reasons of clarity. 
     The flat head or surface  28  of the rail profile  12  or its rail head  22  is spanned in the end state by a profile strip  40  of thickness f of 6 mm which is made of a ferrous or non-ferrous metal. This profile strip  40  is channel-like in cross-section and its side legs  46  of height c 1  of 20 mm, starting from a base plate  42  and parallel to each other and to the longitudinal axis B of the profile strip  40 , lie on the long edges  24  of the rail head  22 . In this position the flat outer surface  44  of width q of the profile strip  40  forms the surface of the composite profile  10 . 
     Allocated to each side leg  46  of the profile strip  40  lying on the surface  28  of the rail head  22 , in the embodiment example of  FIG. 1 ,  2  on the inside, axially parallel, is a channel-like insert rod  50  of approximately V-shaped cross-section with opening angle w 1  of approximately 65°, whose channel legs  49 ,  49   1  of linear cross-section have a thickness a 1  which corresponds with slight play to the width a of the slot  30 . The right channel leg  49  in  FIG. 3  of the insert rod  30 , also called an anchor rod, lies with its outside—running parallel to the cross-sectional longitudinal axis Q—on the inside of the side leg  46  of the profile strip  40  in a contact width c 2  of 5 mm and is welded tightly to this with a weld seam indicated at  48 . This runs on the face  47  of the profile strip side leg  46 . The other channel leg  49   i  is inserted in the adjacent slot  30  of the rail head  22 . This gives a permanent and tight connection under mechanical pretension of the two composite partners  12 ,  40  of the composite profile  10 . This pretension between the composite partners determines their suitability for use; since this pretension is a requirement for the transition resistances, corrosion behaviour and hence life of the power transmission system. 
     The rail head  22   a  of the composite profile  10   a  in  FIG. 5 , instead of a V-shaped slot, has a slot  30   a  of bent angular cross-section of width (radius) 4 mm for a correspondingly formed insert rod  50   a  of the profile strip  40  which is designed in itself according to  FIG. 2 ,  4 . Towards the rail foot  14 , the slot  30   a  is limited by an upwardly tilted longitudinal rib  34   a  of the rail head  22   a . This slot  30   a  holds the free end  55  of the curved cross-section of the insert rod  50   a  which in side view is a longitudinal strip. 
       FIG. 6  shows two insert profiles or insert rods  50   b  of angular or hook-like cross-sectional form for corresponding slots  30   b  in the rail head  22   b  or composite profile  10   b . These insert rods  50   b  are welded to the face  47  of the profile strip side leg  46  by a weld seam  48  and with their free hook section  56  undercut an axially parallel peg strip  37  of width k 1  of the rail head  22   b . 
     The profile strip  40  of  FIG. 7  is designed largely corresponding to that in  FIG. 2 ,  4 ; in this composite profile  10   c  however the two insert profiles or insert rods  50   c  are bent semi-circular in cross-section and at their zenith are each welded to the face  47  of a side leg  46  of the profile strip  40 . The insert rods  50   c  opening to each other in a centre axis M crossing the cross-section longitudinal axis Q, surround at the rail head  22   c  a bead  36  of part-circular cross-section contour which is limited on both sides by longitudinal ribs  34   c  forming insert slots  35  for the cross-section ends of the insert rod  50   c . 
       FIG. 8  in each case shows one half, ending in cross-sectional longitudinal axis Q, of two composite profiles  10   d ,  10   e ; the other halves which are not shown are designed accordingly. Allocated to the profile strip  40  of the embodiment on the left in  FIG. 8  is an insert rod  50   d  of thickness a 1 , the cross-section of which comprises a quarter-circle section  54  and a linear section  49   a  which is welded to the corresponding side leg  46  of the profile strip  40 . This quarter-circle cross-section  54  protrudes towards the rail foot  14 . In the embodiment on the right in  FIG. 8 , the insert rod  50   e  is established so that the quarter-circle section  54  is directed towards the base plate  42  of the profile strip  40 . In both composite profiles  10   d ,  10   e  the linear section rests in a longitudinal recess  32  of the rail head  22   d  or  22   e  which transforms into a slot  30   e  of curved cross-section. 
     The composite profile  10   f  in  FIGS. 9 to 13  contains two insert rods  50   a , the form of which is described for  FIG. 5 . In contrast to that depiction however the free ends  55  of the insert rods  50   a  here point upwards, i.e. towards the base plate  42  of the profile strip  40 . 
       FIG. 11  shows for better clarity, adjacent, the precise structure of this profile strip  40  already described for  FIG. 4 , wherein the width q of its straight outer face  44  here measures 68 mm with an elongated length of around 116 mm and a surface of around 697 mm [mat. 1.4016 (X 6 Cr 17) with 5373.1 g/m]. 
     The insert rod  50   a  according to  FIG. 12 , with faces  57  of its two profile legs  55  and  55   i  of length z of 7.8 mm and z 1  of 5.8 mm respectively, determines an angle y of 65°.  FIG. 13  shows the length of the slot  30  described above and the longitudinal recesses  32  in the rail head  22   f . 
     In the embodiment examples described, the head surface  28  of the rail profile  10 ,  10   a  to  10   f  and/or the under face  45  of the cover profile  40 , for the sake of better holding and electrical contact, are brushed, blasted, galvanically coated or silver-coated. 
     The composite profile  10   g  of  FIG. 14 ,  15  corresponds in its structure to the composite profile  10  of  FIG. 1 ,  2  with the evident difference that the insert rods  50  are each attached both by the weld seam  48  to the face edge  47  of the side leg  46  of the cover profile  40  and also on the other side by a solder or solder weld seam  48   t  to the longitudinal rib  34  of the rail head  22   g . This solder or solder weld seam  48   t  ensures an improvement in the transition resistance and protects against water penetration. Also arrow x in  FIG. 14  shows the impact direction for a tool wedge which is not shown with which a caulking force is applied to the insert rod  50 . 
     On the finished composite profile  10   g  it is no longer evident that between the head face  28  of the rail head  22  and the under face  45  of the cover profile  40 , to improve contact, a film  60  or corresponding layer of contact grease is applied. The film  60  can be a soft pure aluminium film or a solder film or a graphite film and sits firmly between the two faces  28 ,  45 . 
     From the head face  28  of the rail head  22   h  of a rail profile  12   h  of a further design which is sketched only in half in  FIG. 16 , protrude longitudinal webs or web attachments  62 ; in addition or also alone corresponding web attachments  62   s  can protrude from the long edge  24   h  of curved cross-section of the rail head  22   h . These web attachments  62 ,  62   h  which are produced on extrusion-moulding of the rail head  22   h  centrally on the carrier profile  12   h , on the side areas of the head face  28  and long edges  24   h , are deformed on application of the profile strip or cover profile  40  and generate a pretension in the system. 
     The rail profile  12   i  indicated on the right in  FIG. 16  differs from the rail profile  12  in  FIG. 14 ,  15  by a lip web  64  that is attached to the rail head  22   i  as a type of underlip during the extrusion-moulding process and extends the lower faces of the slot  30   i ; after application of the insert rod  50 , this lip web  64  is deformed, creating a support, into the pressure beads  66  by means of pressure rolling carried out along the composite profile  10   i  according to  FIG. 17 . 
       FIGS. 18 ,  19  depict two further possibilities for generating a pretension between the head face of the rail profile and the under face of the profile strip or cover profile, namely firstly a ball-shaped head face  29  of a rail profile  13 , which head face opposes the flat under face  45  of the cover profile  40  and is curved about an attachment point D preferably lying in the rail web  20  and the cross-sectional longitudinal axis Q. Secondly,  FIG. 19  shows a base plate  43 , which is curved towards the flat head face  28  of the fail foot  12 , of a profile strip or cover profile  41 ; the dimensions of curvature of this and its under face  45   k  running symmetrical to the cross sectional longitudinal axis Q corresponds, in inverse curvature direction, to that of the curved head face  29  described in  FIG. 18 , i.e. its radius r corresponds to that of  FIG. 19 . The inner distance q 1  of the side leg  46  of the flat cover profile  40  also corresponds to the inner distance q 1  of the side leg  46  of the curved cover profile  41 . 
       FIGS. 20 to 23  and  25  show the production method according to the invention. First the two insert rods  50  of special steel are supplied to the extruded rail profile  12  according to  FIG. 20  and their inner channel-like legs  49   i  inserted in the respective slots  30 . Then all special steel profiles are applied, i.e. the insert rods  50  and cover profile  40 , the latter on the head face  28  of the rail or carrier profile  12  ( FIG. 21 ). Then these parts are welded under pressure P; the weld nozzles used are referenced  70 . 
     On a lower contact roller  72   t  according to  FIG. 23  lies the unit of cover profile  40  and rail profile  12 , to which are allocated—not shown—the two insert rods  50 . An upper contact roller  72  is allocated to the foot surface  16  of the rail foot  14 . These special rollers  72 ,  72   t  which are adapted and mounted on parallel shafts  74 , exert the necessary vertical pressure, whereas on both sides, on lateral mounting arms  76  of a roof frame  78  each between a pair of bearing plates  77  which are arranged tilted at an angle w 2  of for example 45°, pressure plates  80  which are rotatable on a pulley shaft  79  exert a contact pressure on the insert rods  50  and hold these in the slots  30  of the rail head  22 . This is a modified roll straightening machine for alloy profiles. In order to achieve an optimum pretension, welding is performed between the contact rollers  72 ,  72   t  of antimagnetic material, and the two sides are processed simultaneously. 
       FIG. 24  shows a substantial fragment of the conductor rail  10  according to the invention which offers the required pretension. A corner area of the rail head  22  with slot  30  is evident, as is a channel-like insert rod  50  held therein which on the other side ends at the cross-sectional step  33  of the longitudinal recess  32  of the rail head  22  and is attached to the side leg  46  of the profile strip or cover profile  40 .