Magnetic earth clamp for overhead line equipment structures

Abstract

An earth clamp for an overhead line structure comprising: a clamp frame including a profile having flat contact points at each end of the profile and a middle portion at a different height than the contact points at each end of the profile; and at least one magnetic part disposed relative to the clamp frame for magnetically mounting the clamp frame to a surface, the magnetic part being located toward the middle portion of the frame profile, the magnetic part being disposed such that it can move relative to the frame between the levels of the contact points and away from the level defined by the contact points toward the middle portion to mount the earth clamp to a structure facilitating mechanical and electrical coupling through the magnetic part and the contact points to the overhead line structure, and including means for moving the earth clamp frame and / or the magnetic part relative to the overhead line structure to counteract the magnetic force exerted by the magnetic part on the overhead line structure for the purpose of releasing the earth clamp from the overhead line structure. A corresponding portable earth is also presented.

Description

[Technical Field]

[0001] Generally, the present invention relates to electromechanical arrangements for grounding overhead line structures. In particular, although not exclusively, the present invention relates to a universal portable earth clamp. [Background technology]

[0002] Existing portable grounding solutions for overhead line installations (OLEs) generally require the provision of structure-mounted earth attachment points with associated fasteners, usually in the form of pegs. Existing portable grounding solutions require structure-mounted earth attachment points to apply short portable earths. Such solutions are typically spring-loaded jaw-type designs. Such solutions have the disadvantage of requiring the use of earth attachment points, which are typically only installed 400 meters apart, potentially affecting access and causing work stoppages if each attachment point is missing or damaged. Such earth attachment points are not provided on all structures, limiting the overhead line structures to which portable earths can be applied.

[0003] There is therefore a need for a more versatile earth clamp solution that avoids the use of earth attachment points and allows for the optimization of the time available to perform work within highly constrained rail infrastructure access windows while realizing the attendant safety, time and cost benefits. Summary of the Invention [Problem to be solved by the invention]

[0004] It is an object of embodiments of the present invention to at least mitigate one or more of the above-mentioned drawbacks evident in prior art arrangements. This object is generally achieved by means of an arrangement and method according to the claim set forth. [Means for solving the problem]

[0005] The present invention provides a ground clamp that is particularly usable for OLE structures that provide a suitable ferromagnetic material surface. One application of the present invention is when a single ground or multiple grounds are required on an OLE structure where no dedicated or specific ground attachment point peg exists for application of a conventional ground clamp. Another example includes situations where the ground attachment point peg is damaged or missing, preventing application of a conventional short portable ground. Other applications include situations where a long portable ground would typically be used. Still other applications include situations where it is desired to apply a visible ground at the work site to an OLE structure.

[0006] Benefits of the present invention include providing a short, portable earth that can be used on many overhead line structures with suitable ferromagnetic surface, eliminating the requirement for an earth attachment point. Furthermore, the present invention provides an alternative to the use of long, portable earths in some cases, thus providing a direct safety benefit due to the risks associated with long, portable earths. Furthermore, the present invention provides a short, portable earth option that can be utilized in the event that an earth attachment point is damaged or missing. Furthermore, the present invention allows for the use of a single additional earth on overhead line structures and an optimized approach to grounding. Furthermore, the present invention allows for the application of a visible earth at the work site to OLE structures to demonstrate that the equipment has been de-energized. Furthermore, the present invention is compatible with the use of existing energized working poles and associated send / return adapters.

[0007] According to one aspect of the present invention, there is provided an earth clamp for an overhead wire structure, comprising: - a clamping frame including a profile having flat contact points at each end of the profile and an intermediate portion at a different height from the contact points at each end of the profile; - at least one magnetic part arranged relative to the clamping frame for magnetically attaching the clamping frame to the surface, the magnetic part being located towards a middle part of the frame profile; wherein the magnetic part is arranged in such a way that it can be moved relative to the frame between the levels of the contact points and away from the level defined by the contact points towards the intermediate part to attach the earth clamp to a structure facilitating mechanical coupling and electrical connection with the overhead line structure through the magnetic part and the contact points, - including means for moving the earth clamp frame and / or the magnetic component relative to the overhead line structure to counteract the magnetic force exerted by the magnetic component on the overhead line structure for the purpose of releasing the earth clamp from the overhead line structure; A magnetic component; An earth clamp is provided that includes:

[0008] According to one embodiment of the present invention, the earth clamp includes a mechanical actuation lever for moving the earth clamp frame and / or magnetic components away from a structure when the earth clamp is attached to the structure.

[0009] According to one embodiment of the present invention, a mechanical actuation lever may be used with the delivery head to move the earth clamp frame and / or magnetic components at least away from the structure when the earth clamp is attached to the structure.

[0010] According to one embodiment of the present invention, the clamping frame may include a curved profile.

[0011] According to one embodiment of the present invention, the ground clamp includes a spring coupled to the magnetic component to induce a counteracting force on the magnetic component, urging the magnetic component to move away from the level of the contact point.

[0012] According to one embodiment of the present invention, the connection between the magnet and the spring assembly is electrically isolated from the clamp frame.

[0013] According to one embodiment of the present invention, the magnetic component is electrically coupled to the clamping frame via a flexible braided connection.

[0014] According to one embodiment of the present invention, the earth clamp frame incorporates guides that aid in the correct positioning and application of the earth clamp frame.

[0015] According to one embodiment of the present invention, the earth clamp includes a permanent protective cover applied over the magnet that allows for safe handling and storage when not in use.

[0016] According to one embodiment of the present invention, the ground clamp includes a removable cover for the magnetic components.

[0017] According to one embodiment of the present invention, there is provided a portable earth comprising an earth clamp arrangement as claimed in claim 1 and a line end connected thereto.

[0018] As briefly outlined above, the usefulness of different aspects of the present invention arises from several issues depending on each particular embodiment.

[0019] As used herein, the phrase "a number of" may mean any positive integer starting from one (1). The phrase "a plurality of" may mean any positive integer starting from two (2).

[0020] Different embodiments of the invention are likewise disclosed in the attached dependent claims.

[0021] Some exemplary embodiments of the present invention will now be scrutinized more closely with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 illustrates a front view of one embodiment of an earth clamp. [Figure 2] FIG. 2 illustrates a rear view of one embodiment of the ground clamp. [Figure 3] FIG. 3 illustrates a side view of one embodiment of an earth clamp. [Figure 4] FIG. 4 illustrates an isometric view of one embodiment of an earth clamp. [Figure 5] FIG. 5 illustrates an embodiment of an earth clamp attached to an overhead line structure. [Figure 6] FIG. 6 illustrates an embodiment of an earth clamp attached to an overhead line structure. [Figure 7] FIG. 7 illustrates an overall view of the earth clamp in use. [Figure 8] FIG. 8 illustrates a general view of another embodiment of the earth clamp. [Figure 9] FIG. 9 illustrates another general view of another embodiment of the earth clamp. DETAILED DESCRIPTION OF THE INVENTION

[0023] 1 to 4 illustrate the main aspects of the earth clamp.

[0024] The earth clamp according to the illustrated embodiment includes the following features: (1) Recovery bracket (2) Release mechanism arm (3) Release mechanism hinge point (4) Guide (5) Release mechanism roller (6) Magnets (7A) Clamp frame front contact point (7B) Clamp frame rear contact point (8) Earth cable connection terminal (9) Application lag (10) Insulator (11) Spring (12) Connecting bolt (13) Magnetic Cap Storage Cup (14) Earth cable

[0025] The earth clamp includes at least a clamp frame including a curved profile with a midsection at a different height than the flat contact points (7A, 7B) or pads at each end of the profile and the respective contact points (7A, 7B) at each end of the profile. The contact points (7A, 7B) are fixed and form a horizontal plane or level that can be connected to an OLE structure. The curved profile of the clamp frame may include a continuous profile with rounded edges between the midsection and the contact points (7A, 7B), as illustrated, or the clamp frame profile may include a profile with sharp edges between the midsection and the contact points (7A, 7B), for example, where the horizontal midsection and horizontal contact points (7A, 7B) have vertical or angled areas between them, with sharp corners dividing the different areas to create, for example, a "top hat" shape.

[0026] The earth clamp further includes at least one magnetic component, such as a magnet (6) or multiple magnets (6), disposed on the clamp frame for magnetically attaching the frame to a surface, the magnetic component being positioned toward the center of the frame profile. The magnets (6) are arranged to move between the levels of the contact points (7A, 7B) and above the level defined by the contact points (7A, 7B) relative to the frame, as illustrated in Figures 1 and 2, where the contact surfaces of the magnets (6) are clearly visible as being moved relative to the levels of the contact points (7A, 7B), i.e., away from the level defined by the contact points (7A, 7B), which is also the horizontal level or plane where the magnetic components connect with the OLE structure, and toward the center level of the clamp frame, allowing attachment of the earth clamp to a structure that facilitates mechanical and electrical coupling with the overhead line structure through the magnetic components and the contact points. That is, the magnets (6) are arranged to move vertically "inside" the earth clamp profile, for example via spring connections (11) in the middle of the clamp frame. The earth clamp also includes means, such as a mechanical actuation lever formed by the retrieval bracket (1), release mechanism arm (2), release mechanism hinge point (3) and release mechanism roller (5), for moving the earth clamp, or at least the clamp frame in relation to the overhead line structure, away from the structure by actuating the lever or simply by pulling it, to counteract and overcome the magnetic force exerted by the magnet (6) on the overhead line structure for the purpose of releasing the earth clamp from the overhead line structure.For example, as illustrated in Figures 1-6, the earth clamp includes a recovery bracket (1), a release mechanism arm (2), a release mechanism hinge point (3), and a release mechanism roller (5), whereby operating the recovery bracket (1) causes the release mechanism roller (5) to be pressed against the OLE structure to which the earth clamp is coupled, and mechanical force can be applied via the release mechanism arm (2) and the release mechanism hinge point (3) to move the earth clamp frame relative to the overhead line structure and release the earth clamp from the OLE structure. Alternatively, the earth clamp may include another type of mechanism for moving the earth clamp relative to the OLE structure, such as a recovery bracket (1) directly coupled to the earth clamp frame, as illustrated in the embodiment of Figures 8 and 9, such that pulling the recovery bracket (1) can pull the earth clamp away from the OLE structure. Alternatively or additionally, the earth clamp may include means for moving the magnet (6) away from at least the level of the contact points (7A, 7B). The magnet (6) may be coupled to the spring (11) through an insulator (10) on the frame to help counteract the magnetic force exerted by the magnet (6) and to move the magnet away from at least the level of the contact points (7A, 7B) when the earth clamp is not connected to the structure. In this way, the magnet (6) can move against and attach to the ferromagnetic structure at the same level as the contact points (7A, 7B) that attach the earth clamp to the structure, and the earth clamp frame and / or magnet (6) can similarly be moved away from the connection by movement of the bracket (1), counteracting the magnetic force exerted against the structure and thus removing the earth clamp from the structure. A protective cover, such as a magnet cap storage cup (13), may be used over the magnet to allow safe handling and storage when not in use. The protective cover may be permanently attached or removable. Insulator (10) is used to electrically insulate the magnet and spring assembly from the clamp frame.As illustrated, the magnet (6) may be electrically coupled to the clamp frame via a flexible braided connection.

[0027] The earth clamp may further include a guide (4) for easier manipulation and attachment of the earth clamp to the OLE structure. Such a guide (4) is beneficial since the earth clamp is manipulated by the energized working pole from a distance and at a height. Furthermore, the earth clamp may include an application lug (9) or similar structure for lifting the earth clamp by the energized working pole at a height.

[0028] The earth clamp further includes an earth cable connection terminal (8) connected to the magnet (6) via an earth cable (14) for connecting the earth clamp with the line end.

[0029] Although not illustrated, the ground clamp may include a housing or a removable cover.

[0030] The earth clamp further includes a connection means for connecting the line end and the line to the earth clamp.

[0031] The earth clamp is particularly suitable for railway applications and associated environments including on systems rated at 25kV AC, 12kA.

[0032] Figures 5-6 illustrate an earth clamp attached to an OLE. The earth clamp is shown attached to a flat surface of a ferromagnetic material. The earth clamp is shown connected to a line end, which may include a conventional line end clamp operable at elevated heights, with an energized working pole, where the earth clamp and line end essentially constitute a portable earth. As illustrated, the energized portion is separated by insulators from the rest of the OLE structure, such as a mast to which the earth clamp can be coupled. The cable connection between the line end clamp and the earth clamp can be kept substantially short.

[0033] FIG. 7 shows an exemplary configuration of an earth clamp in use. In this application example, an overhead railway line equipment structure is shown where an operator would use the earth clamp. Operators may use a conventional energized working pole with a suitable launch and retrieval adapter, such as a launch head or other operating socket, to attach and detach the earth clamp at a desired location with a high elevation and a ferromagnetic surface. Operation is simple because installation of the earth clamp on a given area is easy, since only a sufficiently flat ferromagnetic surface is required. Due to magnetic force, the earth clamp automatically attaches to the ferromagnetic surface, and removal is similarly simple, since the magnetic force can be easily overcome via a mechanical activation lever that can be operated by the operator using the energized working pole. As can be seen in FIG. 7, the earth clamp provides a visible earth that can be applied at the work site to verify that the overhead line equipment has been de-energized. Because the earth clamp can be attached to any substantially flat ferromagnetic surface, grounding can be performed at an elevated elevation, avoiding the need for a long portable earth.

[0034] The scope of the present invention is determined by the appended claims and their equivalents. Those skilled in the art will again recognize that the disclosed embodiments have been constructed solely for illustrative purposes, and that the innovative elements scrutinized herein further encompass additional embodiments, combinations of embodiments, variations, and equivalents that may be better suited to each particular use case of the present invention. The present disclosure further includes the following aspects: <<Aspect 1>> 1. An earth clamp for an overhead line structure comprising: - a clamping frame including a profile having flat contact points at each end of the profile and an intermediate portion at a different height from the contact points at each end of said profile; - at least one magnetic component disposed relative to the clamping frame for magnetically attaching the clamping frame to a surface, the magnetic component being located towards the intermediate portion of the frame profile; wherein the magnetic part is arranged to be movable relative to the frame between levels of contact points and towards the intermediate portion away from a level defined by the contact points to allow attachment of the earth clamp to a structure facilitating mechanical and electrical coupling with the overhead line structure through the magnetic part and the contact points; means for moving the earth clamp frame and / or the magnetic component relative to the overhead line structure to counteract the magnetic force exerted by the magnetic component on the overhead line structure for the purpose of releasing the earth clamp from the overhead line structure; A magnetic component; Including earth clamp. <<Aspect 2>> 2. The arrangement of claim 1, wherein the earth clamp includes a mechanical actuation lever for moving the earth clamp frame and / or the magnetic component away from a structure when the earth clamp is attached to the structure. Aspect 3 The arrangement of aspect 2, wherein the mechanical actuation lever is operable with a delivery head to move the earth clamp frame and / or magnetic component away from at least a structure when the earth clamp is attached to the structure. Aspect 4 The arrangement of any one of embodiments 1-3, wherein the clamping frame comprises a curved profile. Aspect 5 The arrangement of any one of aspects 1 to 4, wherein the earth clamp includes a spring coupled to the magnetic component to induce a counteracting force on the magnetic component, the spring moving the magnetic component away from the level of the contact point. Aspect 6 Aspects 6. The arrangement of any one of aspects 1-5, wherein the connection between the magnet and the spring assembly is electrically insulated from the clamp frame. Aspect 7 Aspect 7. The arrangement of any one of aspects 1-6, wherein the magnetic component is electrically coupled to the clamping frame via a flexible braided connection. Aspect 8

[0023] Aspect 8. The arrangement of any one of aspects 1-7, wherein the earth clamp frame incorporates guides to assist in correct positioning and application of the earth clamp frame. Aspect 9

[0023] Aspect 9. The arrangement of any one of aspects 1-8, wherein the earth clamp includes a permanent protective cover applied over the magnet to allow for safe handling and storage when not in use. Aspect 10

[0023] Aspects 1-9. The arrangement of any one of aspects 1-9, wherein the ground clamp includes a removable cover for the magnetic component. Aspect 11 10. A portable earth comprising the earth clamp arrangement of claim 1 and a line end coupled thereto.

Claims

1. 1. An earth clamp for an overhead wire structure comprising: a clamping frame comprising a profile having flat contact points at each end of the profile and an intermediate portion at a different height from the contact points at each end of said profile; at least one magnetic part arranged relative to the clamping frame for magnetically attaching the clamping frame to a surface, the magnetic part being located towards the intermediate part of the profile of the clamping frame; wherein the magnetic part is arranged to be movable relative to the clamp frame between levels of contact points and towards the intermediate portion away from the level defined by the contact points to allow attachment of the earth clamp to a structure facilitating mechanical and electrical coupling with the overhead line structure through the magnetic part and the contact points; means for moving the clamp frame and / or the magnetic component relative to the overhead line structure to counteract the magnetic force exerted by the magnetic component on the overhead line structure for the purpose of releasing the earth clamp from the overhead line structure; A magnetic component; Including earth clamp.

2. 10. The earth clamp of claim 1, wherein the earth clamp includes a mechanical actuation lever for moving the clamp frame and / or the magnetic component away from a structure when the earth clamp is attached to the structure.

3. 3. The earth clamp of claim 2, wherein the mechanical actuation lever is operable with a delivery head to move the clamp frame and / or magnetic component away from at least a structure when the earth clamp is attached to the structure.

4. An earth clamp according to any one of claims 1 to 3, wherein the clamp frame comprises a curved profile.

5. 4. The earth clamp of claim 1, further comprising a spring coupled to the magnetic component to induce a counteracting force on the magnetic component, the spring urging the magnetic component to move away from the level of the contact point.

6. An earth clamp according to any one of claims 1 to 3, wherein the connection between the magnetic part and the spring assembly is electrically isolated from the clamp frame.

7. An earth clamp according to any one of claims 1 to 3, wherein the magnetic component is electrically coupled to the clamp frame via a flexible braided connection.

8. An earth clamp according to any preceding claim, wherein the clamp frame incorporates guides to assist in correct positioning and application of the clamp frame.

9. 4. An earth clamp according to any one of claims 1 to 3, wherein the earth clamp includes a permanent protective cover applied over the magnetic components to allow safe handling and storage when not in use.

10. An earth clamp according to any one of claims 1 to 3, wherein the earth clamp comprises a removable cover for the magnetic component.

11. A portable earth comprising the earth clamp of any one of claims 1 to 3 and a line end connected thereto.

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