HK40112920A - Magnetic earth clamp for overhead line equipment structures - Google Patents

Description

Magnetic grounding clamps for overhead line equipment structures

Technical Field

Generally, the present invention relates to an electromechanical arrangement structure for grounding overhead line structures. Specifically, but not exclusively, the present invention relates to a universal portable grounding clamp.

Background Technology

Existing portable grounding solutions for overhead line equipment (OLE) typically require structurally mounted grounding attachment points with associated fasteners, usually in the form of studs. These solutions require structurally mounted grounding attachment points to apply short portable groundings. Such solutions often employ a spring-loaded clamp design. A drawback of these solutions is the necessity of grounding attachment points, which can hinder access and lead to work cancellations if lost or damaged, as these points are typically only installed about 400 meters apart. The fact that not all structures have grounding attachment points limits the types of overhead line structures where portable grounding can be applied.

Therefore, a more versatile grounding clamp solution is needed that avoids the use of grounding attachment points and allows for associated safety, time, and cost benefits, while optimizing the time available for operation within a very limited window of railway infrastructure access.

Summary of the Invention

The object of embodiments of the present invention is to mitigate at least one or more of the aforementioned defects that are evident in prior art arrangements. This object is generally achieved by the arrangements and methods according to the appended claims.

This invention provides a grounding clamp particularly suitable for OLE structures with a suitable ferromagnetic material surface. One example of application of this invention is when a single or multiple grounding elements are required at the OLE structure, where there are no dedicated or specific grounding attachment pins for applying conventional grounding clamps. Another example includes situations where grounding attachment pins are damaged or missing, thus hindering the application of conventional short portable grounding elements. Some other applications include locations where long portable grounding elements are typically used. Other applications include situations where a visible grounding element needs to be applied to the OLE structure in the work area.

Advantages of this invention include providing a short, portable grounding option that can be used on numerous overhead line structures with suitable ferromagnetic surfaces without requiring the installation of grounding attachments. Furthermore, this invention provides an alternative to using long portable grounding elements in certain situations, thus offering a direct safety benefit due to the risks associated with long portable grounding elements. Additionally, this invention provides a short, portable grounding option that can be used in cases where grounding attachments are damaged or lost. Furthermore, this invention achieves an optimized grounding method and the use of a single additional grounding element at overhead line structures. Furthermore, this invention enables the application of a visible grounding element to an OLE structure in the work field to demonstrate equipment failure. Moreover, this invention is compatible with the use of existing live work poles and associated distribution/recovery adapters.

According to one aspect of the present invention, a grounding clamp for an overhead line structure comprises:

- A clamping frame comprising a profile having a flat contact point at each end of the profile, and the profile having a middle portion at a different height than each contact point at each end of the profile.

- At least one magnetic component, the magnetic component being arranged to the clamp frame for magnetically attaching the clamp frame against a surface, the magnetic component being positioned toward the middle portion of the frame profile.

The magnetic component is arranged relative to the frame between the horizontal planes of the contact points and away from the horizontal plane defined by the contact points, moving towards the central portion to allow the grounding clamp to attach to a structural member that facilitates mechanical and electrical connection of the grounding clamp to the overhead line structure via the magnetic component and the contact points.

The grounding clamp includes a device for moving the grounding clamp frame and/or the magnetic component relative to the overhead line structure to counteract the magnetic force applied to the overhead line structure by the magnetic component, thereby releasing the grounding clamp from the overhead line structure.

According to an embodiment of the present invention, the grounding clamp includes a mechanical actuation rod for moving the grounding clamp frame and/or the magnetic component in a direction away from the structural member when the grounding clamp is attached to the structural member.

According to an embodiment of the present invention, the mechanical actuation rod for moving the grounding clamp frame and/or the magnetic component at least away from the structural member when the grounding clamp is attached to the structural member can be used with a dispensing head.

According to an embodiment of the present invention, the clamp frame includes a curved profile.

According to an embodiment of the invention, the grounding clamp includes a spring connected to the magnetic component to provide a reaction force on the magnetic component and thereby move the magnetic component away from the horizontal plane of the contact point.

According to an embodiment of the present invention, in the grounding clamp, the connection between the magnet and the spring assembly is electrically insulated from the clamp frame.

According to an embodiment of the present invention, the magnetic component is electrically connected to the clamp frame via a flexible braided connection.

According to an embodiment of the present invention, the grounding clamp frame is combined with a guide member, which assists in the correct positioning and application of the grounding clamp frame.

According to an embodiment of the invention, the grounding clamp includes a protective cover permanently attached to the magnet, the protective cover allowing the magnet to be safely handled and stored when not in use.

According to an embodiment of the present invention, the grounding clamp includes a removable cover for the magnetic component.

According to one aspect of the present invention, a portable grounding arrangement structure includes a grounding clamp arrangement structure as described in claim 1 and a line end connected to the grounding clamp arrangement structure.

As briefly reviewed above, the utility of different aspects of the invention stems from a number of issues depending on each particular implementation.

The expression “multiple” in this text can refer to any positive integer starting from one (1). The expression “multiple” can also refer to any positive integer starting from two (2).

Different embodiments of the present invention are also disclosed in the appended dependent claims.

Attached Figure Description

Next, some exemplary embodiments of the invention will be reviewed more carefully with reference to the accompanying drawings, in which...

Figure 1 shows a front view of an embodiment of the grounding clamp.

Figure 2 shows a rear view of an embodiment of the grounding clamp.

Figure 3 shows a side view of an embodiment of the grounding clamp.

Figure 4 shows an isometric view of an embodiment of the grounding clamp.

Figure 5 shows a view of an embodiment in which the grounding clamp is attached to the overhead line structure.

Figure 6 shows a view of an embodiment in which the grounding clamp is attached to the overhead line structure.

Figure 7 shows an overall view of the grounding clamp in use.

Figure 8 shows an overall view of another embodiment of the grounding clamp, and

Figure 9 shows another overall view of another embodiment of the grounding clamp.

Detailed Implementation

Figures 1 to 4 illustrate the main aspects of the grounding clamp.

The grounding clamp according to the illustrated embodiment includes the following features.

(1) Retract the support

(2) Release mechanism arm

(3) Release mechanism hinge point

(4) Guide

(5) Release mechanism roller

(6) Magnet

(7A) Front contact point of the fixture frame

(7B) Rear contact point of the fixture frame

(8) Grounding cable connection terminal

(9) Application of lugs

(10) Insulator

(11) Spring

(12) Connecting bolts

(13) Magnetic lid storage cup

(14) Grounding cable

The grounding clamp includes at least a clamp frame comprising a curved profile having flat contact points (7A, 7B) or pads at each end of the profile, and the curved profile having a middle portion at a different height from each contact point (7A, 7B) at each end of the profile. The contact points (7A, 7B) are fixed and form a horizontal plane or lateral surface, which can be connected to an OLE structure. As shown, the curved profile of the clamp frame may include a continuous profile with rounded edges between the middle portion and the contact points (7A, 7B), or the clamp frame profile may include a profile with sharp edges between the middle portion and the contact points (7A, 7B), for example, wherein there are vertical or angled regions between the horizontal middle portion and the horizontal contact points (7A, 7B), wherein the acute angle divides the different regions, thereby creating, for example, a "cap shape".

The grounding clamp also includes at least one magnetic component, such as one or more magnets (6), at least one magnetic component being disposed to the clamp frame for magnetically attaching the clamp frame against a surface, the magnetic component being positioned toward the center of the frame profile. The magnet (6) is arranged to move relative to the frame between the horizontal plane of the contact points (7A, 7B) and above the horizontal plane defined by the contact points (7A, 7B), as shown in FIG1 and FIG2, wherein it can be clearly seen that the touch surface of the magnet (6) moves above the horizontal plane of the contact points (7A, 7B), i.e., away from the horizontal plane defined by the contact points (7A, 7B), which is also the horizontal plane or plane on which the magnetic component is connected to the OLE structure, and moves toward the horizontal plane of the center of the clamp frame to allow the grounding clamp to be attached to a structural member that facilitates mechanical and electrical connection of the grounding clamp to the overhead line structure via the magnetic component and the contact points. That is, the magnet (6) is arranged to move "inside" the grounding clamp profile, for example, by moving vertically via a spring connector (11) at the middle portion of the clamp frame. The grounding clamp also includes a mechanically actuated rod, such as a retraction bracket (1), a release mechanism arm (2), a release mechanism hinge point (3), and a release mechanism roller (5), to move the clamp frame at least relative to the overhead line structure, such as by rod actuation or simply by pulling the grounding clamp away from the structure, to counteract and overcome the magnetic force exerted on the overhead line structure by the magnet (6), thereby releasing the grounding clamp from the overhead line structure. For example, as shown in Figures 1 to 6, the grounding clamp includes a retraction bracket (1), a release mechanism arm (2), a release mechanism hinge point (3), and a release mechanism roller (5). By operating the retraction bracket (1), the release mechanism roller (5) can press against the OLE structure to which the grounding clamp is connected, and by the release mechanism arm (2) and the release mechanism hinge point (3), a mechanical force can be applied to move the grounding clamp frame relative to the overhead line structure and release the grounding clamp from the OLE structure. Alternatively, the grounding clamp may include another type of mechanism to move the grounding clamp relative to the OLE structure, such as a retraction bracket (1) directly connected to the grounding clamp frame, as shown in the embodiments of Figures 8 and 9, such that the grounding clamp can be pulled away from the OLE structure by pulling the retraction bracket (1). Alternatively or additionally, the grounding clamp may include a device for moving the magnet (6) at least away from the contact points (7A, 7B) on a horizontal plane. The magnet (6) can be connected to the spring (11) via an insulator (10) at the frame to help counteract the magnetic force applied by the magnet (6) and to move the magnet at least away from the horizontal plane of the contact points (7A, 7B) when the grounding clamp is not connected to the structure. Thus, the magnet (6) can move against and attach to the ferromagnetic structure, which is flush with the contact points (7A, 7B) to which the grounding clamp is attached, and the grounding clamp frame and/or the magnet (6) can also be counteracted by the operating bracket (1) and thus the grounding clamp can be separated from the structure and removed from the connection. A protective cover, such as a magnet cover storage cup (13), can be used on the magnet to allow for safe handling and storage when the magnet is not in use. The protective cover can be permanently fixed or removable. The insulator (10) is used to electrically insulate the magnet and spring assembly from the clamp frame. As shown, the magnet (6) can be electrically engaged to the clamp frame via a flexible braided connection.

The grounding clamp may also include a guide (4) to facilitate operation of the grounding clamp and attachment of the grounding clamp to the OLE structure. Such a guide (4) is advantageous because the grounding clamp is operated from a distance and at a height by a live working rod. In addition, the grounding clamp may include an applied lug (9) or similar structure for lifting the grounding clamp together with the live working rod to a height.

The grounding clamp also includes a grounding cable connection terminal (8), which is connected to the magnet (6) via a grounding cable (14) for connecting the grounding clamp to the end of the line.

Although not shown, the grounding clamp may include a housing or a removable cover.

The grounding clamp also includes a connection device for connecting the end of the line to the grounding clamp via a line.

This grounding clamp is particularly suitable for railway applications and related environments, including systems rated for 25kV AC and 12kA.

Figures 5 and 6 illustrate a grounding clamp attached to an OLE. The grounding clamp is shown attached to a flat surface of a ferromagnetic material. The grounding clamp is shown connected to a line end, which may include a conventional line end clamp that can be operated at a height via a live working pole. The grounding clamp and the line end essentially constitute a portable grounding device. As shown, the live portion is separated from the rest of the OLE structure, such as a mast to which the grounding clamp can be connected, by an insulator. The cable connection between the line end clamp and the grounding clamp can be kept relatively short.

Figure 7 illustrates an example of the setup of a grounding clamp in use. This application shows a railway overhead line equipment structure where an operator uses the grounding clamp. The operator can use a standard live-line working rod with suitable distribution and retrieval adapters (e.g., distribution heads or other operating sockets) to attach and remove the grounding clamp at a height and in a preferred location on a surface with ferromagnetic material. Placement of the grounding clamp is simple and easy to operate because only a sufficiently flat ferromagnetic surface is required. The grounding clamp automatically attaches to the ferromagnetic surface due to magnetism, and removal is also simple because the magnetic force can be easily counteracted by a mechanically actuated rod, which the operator can use with the live-line working rod. As can be seen from Figure 7, the grounding clamp provides visible grounding, which can be applied in the work site to demonstrate that the overhead line equipment has failed. Because the grounding clamp can be attached to any substantially flat ferromagnetic surface, grounding can be performed at a height, thus avoiding the need for long, portable grounding devices.

The scope of this invention is defined by the appended claims and their equivalents. Those skilled in the art will again understand that the disclosed embodiments are constructed for illustrative purposes only, and that the innovative points reviewed herein will cover further embodiments, combinations of embodiments, variations, and equivalents more suitable for each particular use of the invention.

Claims (11)

1. A grounding clamp for an overhead line structure, the grounding clamp comprising: - A clamping frame comprising a profile having a flat contact point at each end of the profile, and the profile having a middle portion at a different height than each contact point at each end of the profile. - At least one magnetic component, the magnetic component being arranged to the clamp frame for magnetically attaching the clamp frame against a surface, the magnetic component being positioned toward the middle portion of the frame profile. The magnetic component is arranged relative to the frame between the horizontal planes of the contact points and away from the horizontal plane defined by the contact points, moving towards the central portion to allow the grounding clamp to attach to a structural member that facilitates mechanical and electrical connection of the grounding clamp to the overhead line structure via the magnetic component and the contact points. The grounding clamp includes a device for moving the grounding clamp frame and/or the magnetic component relative to the overhead line structure to counteract the magnetic force applied to the overhead line structure by the magnetic component, thereby releasing the grounding clamp from the overhead line structure. 2. The arrangement according to claim 1, wherein the grounding clamp includes a mechanical actuation rod for moving the grounding clamp frame and/or the magnetic component in a direction away from the structural member when the grounding clamp is attached to the structural member. 3. The arrangement according to claim 2, wherein the mechanical actuating rod for moving the grounding clamp frame and/or the magnetic component at least away from the structural member when the grounding clamp is attached to the structural member can be used with the dispensing head. 4. The arrangement structure according to any of the preceding claims, wherein the clamp frame comprises a curved profile. 5. The arrangement according to any of the preceding claims, wherein the grounding clamp includes a spring connected to the magnetic component to provide a reaction force on the magnetic component and thereby move the magnetic component away from the horizontal plane of the contact point. 6. The arrangement according to any of the preceding claims, wherein the connection between the magnet and the spring assembly is electrically insulated from the clamp frame. 7. The arrangement according to any of the preceding claims, wherein the magnetic component is electrically connected to the clamp frame via a flexible braided connection. 8. The arrangement according to any of the preceding claims, wherein the grounding clamp frame is incorporated with a guide that assists in the correct positioning and application of the grounding clamp frame. 9. The arrangement according to any of the preceding claims, wherein the grounding clamp includes a protective cover permanently attached to the magnet, the protective cover allowing the magnet to be safely handled and stored when not in use. 10. The arrangement according to any of the preceding claims, wherein the grounding clamp includes a removable cover for the magnetic component. 11. A portable grounding device, the portable grounding device comprising a grounding clamp arrangement structure according to claim 1 and a line end connected to the grounding clamp arrangement structure.