AN ARRANGEMENT RELATING TO THE SUSPENSION OF OVERHEAD CABLES

Abstract: The invention relates to a device for use when drawing overhead transmission lines or conductors between insulators on line supporting structures, comprising means for attaching the device to the insulator, and means for guiding the overhead transmission line during mounting of said line. According to the present invention, the device includes an annular element (13) and a line receiving element (18). The line receiving element (18) is housed in the annular element (13) in a manner such as to allow the line receiving element (18) to tilt and to rotate relative to the annular element (13), but to be essentially immovable in an axial direction.

Description: An arrangement relating to the Suspension of Overhead Cables. The present invention relates to a device for use in conjunction with suspending overhead transmission lines or conductors between insulators on overhead line carrying structures such as posts or pylons, comprising means for attaching the device tc the insulator and means for guiding the overhead line as it is drawn between said overhead line supporting structures. Overhead lines are traditionally erected by creating a "thoroughfare" through surrounding terrain, particularly in the case of sparsely populated areas, meaning that the overhead line supporting structures must lie substantially in a straight line. It is necessary tc constantly clear these "thoroughfares" from growth in the form of overhanging branches, among other things. This continuous monitoring with respect to keeping the thoroughfare clear is economically burdensome and consequently it is endeavoured to lead the overhead lines to a distribution net along existing roads for instance, as far as possible that is. These thoroughfares meander through the countryside, meaning that the line carrying structures will often be offset relative to each other and necessitating adaptation of the overhead lines to the orientation of said structures. The task of mounting an overhead line between supporting structures, such as posts, is carried cut with the aid of line drawing devices or line guides that are connected to one end of an insulator. With regard to this known technology, reference is made tc 3Ξ 503 312. This pricr publicaticn describes an insulator whose upper end includes a sleeve part which is adapted tc receive the overhead line to be laid overhead. Although the sleeve is affixed tc the upper part of the insulator, it is not intended to automatically adjust its angular position between mutually offset line carrying posts. SE 465 238 teaches an overhead line guide that comprises mutually parallel side walls and rotatable rollers mounted therebetween. SE 503 840 teaches a similar construction. The present invention relates to a device for use when drawing overhead lines between insulators on respective overhead line supporting structures, e.g. posts or pylons, said device including means for attaching it to the insulator and means for guiding the overhead line as it is erected, and has as its object the provision of an improved device which will enable the overhead line to be drawn at different angles and in different height positions of the posts, without requiring preceding adjustment of said device. This object is achieved with an inventive device having the characteristic features set forth in Claim 1. Because the overhead line receiving member can tilt essentially freely and is able to rotate in the annular member or sleeve through 360°, the direction of the overhead line can be guided and controlled automatically within certain limits. In principle, an inventive device is comprised solely of two mutually coacting components, therewith providing a simple construction. The annular component is conveniently divided into separate parts, while the overhead line receiving component may be produced in a casting process. The components can be readily and quickly joined together to form a single unit. Manufacturing costs are therefore low, which is highly beneficial due to the fact that the device is left in place when drawing of the overhead line is completed, where it can later be used in the event of drawing a new overhead line between the posts or in making any subsequent adjustment . In one embodiment of the invention, the inventive device is connected to a connecting body which is intended to be placed on the upper end region of an insulator. According to one embodiment, the connecting body is removably connected to the annular component of the inventive, novel device. In one variant of the inventive device, the connecting body and the annular component together form an indivisible unit. In another embodiment, the annular component is comprised of two suitably semi-cylindrical parts that can be held together by means of a nut/bolt joint. So that the invention will be more readily understood and further features thereof made apparent, the invention will now be described with reference to a preferred embodiment of the novel overhead line guiding device and also with reference to the accompanying drawings, in which Fig. 1 is a side view of the inventive device; Fig. 2 shows the device of Fig. 1 from beneath; Fig. 3 is a front view of the device shown in Figs. 1 and 2, with the overhead line receiving component being shown in one of two vertical limit positions; and Fig. 4 illustrates the inventive device in perspective. The illustrated and preferred embodiment of the line guide or line drawing device 10 is adapted for removable attachment to the outer end region of an insulator 11, suitably by means of a connecting body 12. In the illustrated embodiment, the connecting body 12 is affixed to the lower part of an annular element 13 that presents an opening 40. It will be understood that the connecting body 12 may alternatively be connected detachably to the annular element 13. In one preferred embodiment of the invention, the annular element 13 of the novel line drawing device or line guiding device is suitably comprised of identical semi-cylindrical parts 13' , 13" which have at mutually opposing ends a respective thickening 14, 14' and 15, 15' . Each thickening includes an elongated, through-passing bore. The bores in the thickenings will be in alignment with one another when the two semi-cylindrical parts 13', 13" are joined together. A threaded bolt 16 is inserted through the bores and a nut 17 then screwed onto the free end of respective bolts. The two semi-cylindrical parts 13', 13" form the annular or sleevelike element 13 when joined together. The second component of the inventive line drawing device is comprised of the line receiving element generally referenced 18 in the drawings. The line receiving element 18 has a generally U-shaped cross-section and includes mutually opposing and mutually spaced elongated side walls 19, 20. When seen from the side, the side walls 19, 20 are slightly arcuate in shape and are interconnected by a curved base part 21 which, in the illustrated case, extends solely along the central region of the walls 19, 20. The upwardly facing surface of the base part 21 may be provided with a known friction reducing agent, such as a Teflon® coating. Guide and slide rollers 22, 23 are rotatably mounted on shafts between the inside of the outer end regions of respective side walls 19, 20. In a preferred embodiment, the abutment plane of the guide and slide rollers lies slightly above the plane of the base part 21. The rotatable rollers 22, 23 may conveniently have some type of U-shape or V-shape so as to enable more effective guiding of the line or conductor (not shown) to be mounted. The line receiving element 18 is suitably cast from aluminium and includes mutually spaced, outwardly projecting lower flanges 24, 25 which merge into mutually divergent flanges 24', 25' on the outside of respective side walls 19, 20. The gap between the flanges 24, 25 on the underside of the element 18 is intended to coact with the inside of the annular element 13, possibly with a small amount of play, whereas the divergent flanges 24' and 25' form at the vertical outsides of respective side walls 19, 20 delimiting surfaces for limiting tilting movement of the line receiving element 18 in said annular element 13. The bottom, outwardly projecting flanges 24, 25 also form abutments for preventing horizontal or axial displacement of the line receiving element 18. Wire tie support means for securing the line are shown at 26, these ties being known to the art and forming no part of the present invention. In one embodiment of the invention, the line receiving element 18 can be fitted in the annular element 13 by releasing the nut/bolt joint 16, 17 and removing the upper semi-cylindrical part, and then placing the line receiving element 18 in a position in which the bottom part of the annular element 13 with its outer surface lies in the gap between the bottom flanges 24, 25 of the element 18. The upper part of the annular element 13 is then fitted in the described manner so that the device is ready for use. As will be understood by the person skilled in this art, the two-part annular element 13 may alternatively be an indivisible unit and that the line receiving element 18 may be comprised of two mutually joinable parts which allow said element to be inserted manually into the annular element. In the assembled state shown in the drawings, the line receiving element 18 projects from the annular element 13 on both sides thereof. An essential feature of the invention is that- the element 18 has the aforesaid degrees of freedom, i.e. limited tilting movement in two directions within the annular element 18, can rotate through 360° inside said annular element, and the provision of a given horizontal clearance between the element 18 and the annular element 13. If considered appropriate, the rotatability of the element 18 inside the annular element may be restricted through the medium of stops or the like. The overhead transmission line (not shown in the drawings) is introduced into the line receiving element 18 and will rest generally on the rotatable rollers 22, 23, which are preferably made of a suitable plastic material. In the illustrated case, the element 18 will be rotated within the annular element 13 as the line is stretched, or will tilt vertically in one of two directions to a limited extent determined by the abutments 24' , 25' . The aforedescribed improved overhead transmission line drawing device can therefore compensate for any angular deviations between mutually adjacent posts and also for any differences in height therebetween, without requiring manual adjustment. The inventive device is intended to remain permanently on the insulator, subsequent to mounting the transmission line. Several modifications are conceivable within the scope of the invention. For instance, the semi-cylindrical parts 13', 13" of the annular element 13 can be detachably joined together in a manner other than that described and illustrated. The distance between respective abutment-limiting flanges 24, 25 and 24', 25' on the line receiving element 18 may be changed as desired and necessary. The plane on which the transmission line to be mounted slides is located on a plane which lies beneath the centre plane of the annular element 13 and slides essentially on the rotatable rollers 22, 23. The line receiving element 18 is constructed so that friction will occur solely in response to rotary movement of the component inside the annular element 13.

Claims: CLAIMS 1. A device for use in conjunction with drawing overhead transmission lines or conductors between insulators on line supporting structures, e.g. posts or pylons, comprising means for attaching the device to the insulator and means for guiding the transmission line during mounting of said line, characterised in that the device includes an annular element (13) and a line receiving element (18) ; in that the line receiving element (18) is housed in the annular element (13) and projects out on both sides thereof; and in that the line receiving element (18) is vertically tiltable and rotatable relative to the annular element, but axially immovable. 2. A device according to Claim 1, characterised by a connecting body (12) firmly connected to the annular element (13) . 3. A device according to Claim 1, characterised in that the connecting body (12) is detachably connected to the annular element (13) . 4. A device according to any one of the preceding Claims, characterised in that the annular element (13) is comprised of two removably connected parts (13', 13"), preferably semi- cylindrical parts. 5. A device according to Claim 1, characterised in that the line receiving element (18) is comprised of two mutually connectable parts; and in that the annular element (13) is comprised of an indivisible unit. 6. A device according to any one of the preceding Claims, characterised in that the line receiving element (18) housed in the annular element (13) is restricted for tiltable movement and for limited rotation in said annular element, but axially immovable. 7. A device according to one or more of the preceding Claims, characterised in that the line receiving element (18) is positioned in the annular element (13) with a clearance therebetween. 8. A device according to one or more of the preceding Claims, characterised in that the line receiving element (18) has a generally U-shape cross-section; and in that the two end regions of said element slope downwards in relation to a horizontal plane. 9. A device according to one or more of the preceding Claims, characterised in that the underside of the line receiving element (18) slides co-actingly with the inside of the annular element (13) . 10. A device according to one or more of the preceding Claims, characterised in that one or both outer surfaces of the line receiving element (18) includes/include flanges (24, 25; 24', 25') which extend at least in the transverse direction of said component and project out from its surface and which function as stop abutments for the annular element (13) such as to restrict tilting ? movement of the line receiving element (18) . 11. A device according to one or more of the preceding Claims, characterised in that the line receiving element (18) is slightly arcuate when seen from one side; and in that at least one rotatably mounted roller (22, 23) is provided in the region of respective end-parts. 12. A device according to one or more of the preceding Claims, characterised in that the surface of the line receiving element (18) against which the transmission line is intended to rest is located beneath the centre plane of the annular element (13) . 13. A device according to one or more of the preceding Claims, characterised in that the two semi-cylindrical parts (13', 13") of the annular element (13) are joined detachably together with the aid of a nut/bolt joint (16, 17) . 14. A device according to one or more of the preceding Claims, characterised in that one or both outer side surfaces of the line receiving element (18) include means (26) for guiding and fastening a wire tie around the transmission line.

Inventors: KAELLGREN HAAKAN, KAELLGREN, HAAKAN
Applicants: KAELLGREN HAAKAN, NECKS LB MATERIAL AB, KAELLGREN, HAAKAN, NECKS LB-MATERIAL AB
Application year: 1999
Main classification: H02G1
IPC codes: H02G1, H02G7