RAIL INSULATOR FOR THE SECURING OF A CONDUCTOR RAIL ON A RAIL SUPPORT

Abstract: A rail insulator (5) for the securing of a conductor rail (2) on a rail support (4) which comprises a substantially U-shaped supporting rail in which holes are provided at regular intervals, preferably in two parallel rows, and where the rail insulator (5) is formed with a notch (18) corresponding to the thickness of the rail being used, is arranged so that on the side turning away from the notch it has outwardly - extending, hook-formed holding elements (24, 25) arranged to grip around and be secured to the rail support (4), in that between the holding elements there is provided a guide stud (30) which fits down into one of the holes in one of the rows of holes.

Description: RAIL INSULATOR FOR THE SECURING OF A CONDUCTOR RAIL ON A RAIL SUPPORT. This invention relates to a rail insulator as presen- ted in the preamble to claim 1. Many different forms of rail insulators are known for the building up of rail areas, for example for use in metal-enclosed electrical systems and in power supply installations of similar kind. The rail insulator in accordance with the invention finds application not only in the supply of current or the distribution of power, but also for pilot wires and control leads, for example such as those used in electrical instal- lations in various concerns and the like. As disclosed in British patent no. 1,085,372, a mod¬ ule building set is known for the building up of el¬ ectrical rail areas by the assembling together of rail supports and insulators. The rail supports have notches in which the insulators are placed. One must thus have different supports, all depending on how many conductors there are to be used in the actual installation, and if many conductors are to be led forward, it is easy to obtain a mechanical construc¬ tion which is not strong and stable enough if great changes occur in the current in the conductors, in that the dynamic forces must be transferred by the rail supports. From the Swiss patent publication no. 486,754 is known another module building set for the building up of rail areas, wherein one uses a series of dif¬ ferent forms of rail insulators of plastic which can be assembled so that they surround the rail and are secured by a bolt extending from rail support to rail support. It is thus necessary to have a large number of rail insulators in order to be able to build up a rail area in which are used conductor rails of dif¬ ferent dimensions. As disclosed in USA patent no. 2,445,463, there are known rail insulators for mounting on rail supports which are substantially U-shaped, in that the rail insulator is formed to be secured on the rail support by means of one or more bolts which are secured in threaded holes in the insulator, and pass through holes in the rail support. One thus achieves a reas- onably solid construction, but an installation which is troublesome to change, because a large number of bolts have to be completely screwed out during•the dismantling and screwed in again in forming the new assembly. As disclosed in USA patent no. 2,310,919, there are known rail insulators which are designed to be fast¬ ened to a rail support by screws, each of such insu¬ lators being provided with a notch which corresponds to the thickness of the rail being used. Also in this case the method of securing the rail insulator is unfortunate when it comes to changing the installa¬ tion, the reason being that each insulator is fast¬ ened directly to the rail support by means of screws. The object of the invention according to the present application is to provide a rail insulator for use in the building up of rail areas in which the insula¬ tors can be removed from and mounted on the rail sup- OMPI port quickly and easily, and without diminishing the strength and the ability of the construction to ab¬ sorb mechanical forces from changes in current. This is achieved by forming the rail insulator as characterized in claim 1. With such a construction, it is possible to mount rail insulators on the rail support wherever this may be desired. Moreover, if the spaces between the rail insulators are filled out with distance pieces, or if the insulators are ar¬ ranged completely up against each other, a very rigid and mechanically stable construction is achieved in which the dynamic forces can be transferred through the adjacent insulators. Since the rail support has holes along the whole of its length, one can always distribute the conductor rails uniformly across the whole of the support, so that the mechanical effects from the electric current are the least possible. With the rail insulator according to the invention formed as presented in claim 2, the conductor rail can be bolted securely to the rail support or between two rail supports, all depending on the size of the conductor rail and the current which has.to run through the rail. Thus it is possible to use the same rail support for all sizes and forms of rail areas. Similarly, the rail insulator can be used for conduc¬ tor rails of many different dimensions, in that the bolts merely need to be of different lengths. The invention will now be described in more detail with reference to the drawing which shows various em¬ bodiments of the invention, and where fig. 1 shows a cross-section seen from the end of a part of a rail area for very heiavy currents, built up with the rail insula¬ tor according to the invention, fig. 2 shows a cross-section seen from the end of a part of a rail area for heavy cur¬ rents, built up with rail insulators ac¬ cording to the invention, fig. 3 shows a cross-section of a part of a rail area for smaller currents, built up with rail insulators according to the invention, fig. 4 shows an insulating housing for the in¬ sulation of a bolt head, fig. 5 shows a part of a rail support, fig. 6 shows the rail support in fig. 5, but seen in the direction VT-vT, fig. 7 shows a rail insulator seen in cross -section, and fig. 8 shows in detail how a conductor rail is bolted to a rail support, corresponding to the embodiment in fig. 2. In fig. 1 is seen a double phase rail 1, each of the copper rails being capable, for example, of carrying 1500 Amps, and thus a total of 3000 Amps. Each rail is secured by each its own rail insulator 5, each having a smooth, rectangular notch 18 which corres- ponds precisely to the rail. Copper rails of this kind are normally produced in module measurements of 6 mm, i.e. the thickness of the rail is a multiple of six. In the case shown in the drawing, the phase rail is 12 mm thick and approx. 130 mm high, which corres¬ ponds to a phase rail capable of carrying 1500 Amps. For different current intensities there are produced and used rails with different heights but of the same thickness, so that the same size of insulator 5 can be used for many different conductor rails for differ¬ ent current intensities. The rail insulator 5, also called a rail shoe, is secured to a rail support 4 comprising a U-shaped supporting rail which is shown in detail in figs. 5 and 6. The supporting rail is a formed metal rail with several rows of holes, and hav¬ ing in each end an end piece which can engage with and be secured to a securing bracket 9. In the middle • of the rail support there is a series of holes 32 through which a securing bolt 10 can be introduced, and two parallel rows of smaller holes 31, every alt¬ ernate of " these holes lying opposite one of the lar¬ ger holes 32. The smaller holes 31 are intended for the guide stud on the rail insulator or a distance piece, which will be explained later. In fig. 1 it will also be seen that between the two phase rails 1 and the next phase rail are mounted distance pieces 7 between the rail insulators 5, so that the rail support 4 with rail insulators 5 and distance pieces 7 comprise a solid, firm and rigid beam which supports the phase rails 1. This construc¬ tion prevents any lateral displacement of the rail insulators 5 and thus also lateral displacement of the phase rails. The rail insulator 5 is secured OMPI " firmly against the conductor rail 1 by a bolt 10, which similarly tightens the two rail supports in towards each other. At each end of the bolt there is a nut 14, a locking or friction washer 13 and a wash- er 12, which parts lie down in a housing 11 formed of insulating material. This can be seen in detail in fig. 4. The insulating bolt housing 11 comprises a hollow part 22 in which the nut or bolt head and the different washers can be received, and a hollow part 23 in which the shaft of the bolt can be received. In figs. 7 and 8 it will be seen that in each side of the rail insulator 5 there is formed an arcuate re¬ cess 35, so that two rail insulators lying adjacent to each other form a hole in which the lower part of the insulator's bolt housing can be received. This can be seen more clearly in fig. 8. The shaft of the Bolt 10 does not need to be insulated, the reason being that it extends between the two uninsulated rails 1 which carry the same voltage. The insulating bolt housing increases the leakage distance from the nut or bolt head and to the rail support, hereby pre¬ venting the occurrence of leakage current. Preferably, the rail insulators 5 are 24 mm broad, and the distance pieces 7 are preferably 12 mm broad, so that on the rail support 4, see fig. 5, there is a distance of 12 mm between the small holes in the two parallel rows and 24 mm between the large holes, thus enabling rail insulators and distance pieces to be mounted between each other as desired, while still achieving a very solid fastening of the conductor rail which can withstand the very strong forces which arise between the conductors as a result of short- OMPI circuit currents or high surges of cut-in current. Fig. 2 shows the same parts as in fig. 1, but used for one-sided securing of a pair of rails 2 for cur- rent intensities in the range of 2 x 1000 Amps. The conductor rails have a height of approx. 50 mm and 2 thus a copper cross-sectional area of 600 mm . With these current intensities it is sufficient with one rail support 4, so that one merely uses a shorter bolt 15 together with a rail holder 16 which is se¬ cured by the bolt. With currents of lower intensities, for example in the range below 125 Amps, one can use a rail insula- tor 6 as shown in fig. 3, where the notch 21 which must carry the conductor rail 3 is provided with a narrowed-down opening 20, so that one or τfcwo locking edges are formed. In order for the locking edges to be suitably flexible during the insertion or removal of a rail 3, the notch 21 can be provided with an ex¬ tra notch or recess 19. In fig. 3 there is shown a 6 x 6 mm copper rail for a maximum of 125 Amps, but it will be obvious that rail insulators can also be formed for small, rectangular rails of, for example, 6 x 12 mm or larger. After so many distance pieces 8 have been inserted so that the rail support 4 is com¬ pletely filled up, the conductor rails 3 will be locked, the reason being that the lobes of the rail insulators cannot be bent to the * side before one or more of the distance pieces 8 have been removed. In detail in fig. 8 can be seen how a rail insulator 5 is formed, in that fig. 7 shows a plane section through such an insulator. The distance pieces 7 and 8 shown in the earlier figures have substantially the same cross-section, but merely without the notch 18 or 21 for the conductor rail. In fig. 7 it will be seen that the rail insulator 5 to the one side has an oblong notch 18 for the con¬ ductor rail, and that in this side there are provid¬ ed the arcuate recesses 35 for bolt and bolt housing. On the other side there are provided two outwardly extending hook-formed flanges 24 and 25, said flanges being arranged to grip around and hold firmly on the rail support, see fig. 8. Between the flanges is seen a stud 30 which fits into the small holes 31 in one of the two parallel rows of holes in the rail sup- port. The stud 30 is disposed in such a manner that it makes no difference how the insulator 5 is turn¬ ed, in that apart from the stud 30 and the hooks of slightly different shape on the flanges, it that it is completely symmetric in form. The flanges 24 and 25 can also be provided with holding lugs 27 for an insulating cover 29 for covering the bolt heads and the rail support, and on which there can be provided marking 36 for the relevant conductor. Moreover, by providing the flanges 24 and 25 with holding elements 26 for an insulation cover 28, one can mount said in¬ sulation covers 28 between the individual rail sup¬ ports for covering over the conductor rails. Fig. 8 shows a cross-section in a rail support pre- cisely through a securing point for one conductor rail for currents of average intensity, for example corresponding to fig. 2. it can be seen how the bolt 15 secures a rail 2 to the rail support 4 by means of nut 14 and rail holder 16. The bolt housing 11 sur- rounds the bolt head inside the U-shaped rail support and prevents leakage current from running from the bolt to the rail support. The lower part 23 of the bolt housing 11 reaches exactly as far down as the rail insulator 5.. It can also be seen how the hook -formed flanges have hooks which differ slightly in shape, so that they both sit sufficiently firmly and are sufficiently easy to remove and attach to the rail support. The rail insulator 5, 6, the distance pieces 7, 8 and the bolt housing 11 are produced by form mould¬ ing of an insulating material, preferably of a mat¬ erial such as Arylef U100, which- has good insulating characteristics as well as being well-suited for form moulding. By forming a module building set as described above, with a few different parts it is possible to build up any desired coupling configuration in a rail field, for both high and low current intensities and for both power distribution as well as control purp¬ oses. - * £TJRE OMPI * - °*.

Claims: C L A I M S 1. Rail insulator (5, 6) for the securing of a conductor rail (1, 2, 3) on a rail support (4) which comprises a substantially U-shaped supporting rail in which holes (31) are provided at regular intervals, preferably in two parallel rows, and where, the rail insulator (5, 6) is formed with a notch (18, 21) which corresponds to the thickness of the rail being used, c h a r a c t e r i z e d in that the rail in¬ sulators (5, 6), on the side turning away from the notch, have outwardly-extending, hook-formed holding elements (24, 25) which are arranged to grip around and be secured to the rail support (4) , in that between the holding elements there is provided a guide stud (30) which fits down into one of the holes (31) in one of the rows of holes. 2. Rail insulator according to claim 1, c h a r ¬ a c t e r i z e d in that a recess (35) with arc¬ uate cross-section is provided in the middle of each side of the rail insulators (5) . O PI ?o

Inventors: LOEGSTRUP JOERGEN, SPARRE PREBEN CHRISTIAN, LOEGSTRUP, JOERGEN, SPARRE, PREBEN, CHRISTIAN
Applicants: LOEGSTRUP STEEL AS, A/S LOEGSTRUP-STEEL
Application year: 1983
Main classification: H01B17
IPC codes: B60M1, H01B17, H02G5