WO2022090166A1

WO2022090166A1 - Potential equalisation of a moving cable of a cable-drawn conveying device

Info

Publication number: WO2022090166A1
Application number: PCT/EP2021/079563
Authority: WO
Inventors: Lothar Schmidt; Markus Bischofberger; Antonie IHLN
Original assignee: Innova Patent Gmbh
Priority date: 2020-10-27
Filing date: 2021-10-25
Publication date: 2022-05-05
Also published as: AT524407A1; ES2976041T3; JP2023553242A; EP4238394A1; EP4238394B1; JP7536363B2

Abstract

The invention relates to an arrangement for potential equalisation of a moving cable (10) of a cable-drawn conveying device with a defined electrical reference potential of the cable-drawn conveying device. A potential equalisation unit (1) is provided, with at least one brush body (2) and, arranged therein, at least one electrically conductive contact bristle (3) made of electrically conductive plastic, the potential equalisation unit (1) being arranged relative to the moving cable (10) to allow a potential equalisation between the at least one electrically conductive contact bristle (3) and the moving cable (10), and the at least one electrically conductive contact bristle (3) being electrically conductively connected to at least one potential point (14) having the electrical reference potential.

Description

Equipotential bonding of a moving rope of a rope-pulled conveyor

The present invention relates to an arrangement for equipotential bonding of a moving cable of a cable-pulled conveyor device with a defined electrical reference potential of the cable-pulled conveyor device.

Cable-drawn conveyors, such as cable cars, elevators, etc., use cables, usually made of steel or a combination of steel and plastic, to transport a conveyor unit, e.g. cable car, usually between two or more cable car stations. In principle, pure synthetic ropes are also possible. A cable of the cable-pulled conveying device can be designed as a supporting cable and can be tightly stretched between two points, for example two cable car stations. However, a cable of the cable-pulled conveying device can also be designed as a conveying cable and can be moved, either running back and forth or rotating. With a rope in the form of a hoisting rope, for example, the cable car vehicles or an elevator car are moved, either by the hoisting units being firmly or releasably clamped to the rope or by the hoisting units being pulled through the rope. For safety reasons, ropes must be electrically grounded in order to safely dissipate any electrical charge on the rope, for example due to electrostatic charging, lightning strikes, coupling of electrical currents through electrical fields, etc. In principle, the rope can also become electrically charged if the rope itself is not designed to be electrically conductive. In the case of tightly stretched cables, such a potential equalization to a defined reference potential, for example earth, is easy to implement because the cable can be securely contacted, for example by means of contact clamps. In the case of moving ropes, on the other hand, equipotential bonding is difficult because the moving rope must have safe and permanent electrical contact for equipotential bonding.

So far, cable pulleys, for example deflection pulleys of a circulating cable in a cable car station, or cable pulleys, for example a pulley battery, have often been designed to be electrically conductive for grounding moving cables. For example, electrically conductive contact elements, such as metal plates or pins, were used on the running surface of a cable pulley or pulley, or the running surface itself was designed to be electrically conductive, e.g. in the form of a cable pulley lining or a rubber pulley, for example in the form of an electrically conductive plastic. The electrical contacting of the conductive elements of the running surface was made via the bearing of the sheave or sheave. In order to produce an electrical contact, it is provided that the cable makes electrically conductive contact with the conductive elements of the cable pulley or cable pulley. The disadvantage of this solution can be seen in the fact that such electrical contact elements wear out quickly on the running surface and are often readjusted need to maintain contact with the rope. Electrically conductive rubber pulleys or sheave linings lose their electrical conductivity with age and must therefore also be replaced frequently.

Also known are rotatably mounted grounding pulleys that are in contact with the moving cable and run along with the cable. The electrical contacting of the grounding rollers is made via the bearing of the grounding roller. Designs are known as brush rollers with copper brushes on the circumference of the grounding roller or full rollers with an electrically conductive running surface. Solid rollers have a high running noise. Brush rolls wear out very quickly. In addition, the surface of the rope can be damaged by the brush of the brush roller, especially with steel and plastic ropes. However, a more serious disadvantage of such grounding pulleys is that the bearing of the grounding pulley begins to become electrically insulating from a certain cable speed due to the bearing lubrication, with the result that the grounding function can no longer be guaranteed.

Also known are fixed, flat sliding contacts made of electrically conductive material, which are pressed against a moving cable. WO 2018/150149 A1, for example, shows such a sliding contact made from a mixture of copper and carbon. With such sliding contacts, too, the disadvantage can be seen in the wear of the sliding element. Apart from that, the grinding element must be pressed against the cable in order to achieve adequate and reliable electrical contact, which requires an additional pressing device with moving components.

It is an object of the present invention to specify an electrical potential equalization of a moving cable, with which the disadvantages mentioned above can be eliminated.

This object is achieved by providing a potential equalization unit with at least one brush body and with at least one electrically conductive contact bristle made of electrically conductive plastic arranged therein, the potential equalization unit being arranged relative to the moving cable in order to achieve potential equalization between the at least one electrically conductive contact bristle and to enable the moving cable and the at least one electrically conductive contact bristle is electrically conductively connected to at least one potential point with the electrical reference potential.

Such a potential equalization is extremely simple in structure and use. The equipotential bonding unit only needs to be arranged in such a way that equipotential bonding is possible. The contact bristles are connected to a potential point of the cable-pulled conveying device in order to establish potential equalization. This can be done directly via the contact bristles or via the brush body. An electric one can also do this Conductors are used, whereby the connection to the potential point can be simplified.

The at least one contact bristle is advantageously designed to be elastic and the potential equalization unit is arranged relative to the moving cable in such a way that the at least one elastic and electrically conductive contact bristle makes electrical contact with the moving cable. Due to the elastic, conductive contact bristles, the equipotential bonding unit does not have to be actively pressed against the cable. This reduces the mechanical stress on the equipotential bonding unit and the cable. Apart from that, no pressing mechanism is required. However, the equipotential bonding unit can also be arranged relative to the moving rope in such a way that the at least one electrically conductive contact bristle is arranged at a distance from the rope. The equipotential bonding unit is advantageously arranged in such a way that the tip of the at least one contact bristle, or the entire brush pile, faces the cable. In this case, the equipotential bonding takes place through electrical flashover between the cable and contact bristle as soon as the electrical potential difference is large enough. A certain electrical potential of the cable is accepted and the potential equalization only takes place when this is exceeded.

In order to be able to easily align the potential equalization unit relative to the cable, it is advantageously provided that the potential equalization unit is arranged on a holder with which the potential equalization unit is fastened in the cable-pulled conveying device and with which the potential equalization unit can be adjusted relative to the holder in order to position the potential equalization unit relatively to be able to adjust to the rope.

The present invention is explained in more detail below with reference to FIGS. 1 to 4, which show advantageous configurations of the invention by way of example, schematically and not restrictively. while showing

1 shows a potential equalization unit according to the invention on a holder, FIG. 2 shows an arrangement of the potential equalization unit in a rope-pulled conveyor

3 possible arrangements of the equipotential bonding unit relative to the cable and FIG. 4 a cable with plastic inserts.

The potential equalization unit 1 according to the invention for moving cables of a cable-pulled conveying device, as shown in FIG. As a rule, a brush pile made of a large number of elastic contact bristles 3 made of electrically conductive plastic arranged next to one another is provided. At least one Contact bristle 3 is arranged in brush body 2 . If there are several contact bristles 3, several brush bodies 2 can also be provided. The brush body 2 is preferably designed to be elongated in the direction of the moving cable, particularly in the case of a brush pile. "Longitudinally stretched" here means that the extension of the brush body 2 in the direction of movement of the moving cable is greater than transversely thereto. The at least one electrically conductive contact bristle 3 can be electrically contacted. For example, an electrical conductor 4 is arranged on the brush body 2, for example screwed on as in FIG. For example, the brush body 2, in which the at least one contact bristle 3 is arranged, can be made of an electrically conductive material, such as metal or electrically conductive plastic. In this way, the at least one contact bristle 3 can also be electrically contacted via the brush body 2 . In this embodiment, too, the electrical conductor 4 for contacting the contact bristle 3 via the brush body 2 can be arranged on the brush body 2 . Of course, several electrical conductors 4 can also be provided.

The potential equalization unit 1 can be arranged on a holder 5, preferably exchangeable, with which the potential equalization unit 1 can be attached to a component of the cable-pulled conveyor. For this purpose, for example, the at least one brush body 2 can be arranged on the holder 5 . The potential equalization unit 1 can be arranged in the area of a moving cable 10 by means of the holder 5, so that the electrical potential equalization with the potential equalization unit 1 is made possible. For this purpose, the at least one contact bristle 3 can make electrical contact with the cable 10, as shown in FIG.

The component of the cable conveyor device on which the equipotential bonding unit 1 is arranged can be a stationary component, for example part of a stationary structure (for example a cable car station) of the cable conveyor device. However, the component can also be a moving component of the cable-pulled conveying device, such as a cable car or an elevator car. In this case, a relative movement between the cable 10 and the equipotential bonding unit 1 may or may not be provided. In the case of a moving component, an electrical connection is provided between the moving component and the equipotential bonding unit 1 thereon and the potential point 14 of the cable-pulled conveyor device, for example by means of sliding contacts.

If the cable-drawn conveyor is a cable car, cable car vehicles are often disconnected from the cable 10 in the cable car station. In this case it can be provided that the equipotential bonding unit 1, which is arranged outside the cable car station on the cable car vehicle, is separated from the cable car vehicle in the cable car station and remains on the rope 10. A relative movement between the cable 10 and the equipotential bonding unit 1 can also be provided.

The equipotential bonding unit 1 can also be arranged so that it can be adjusted relative to the holder 5 (as indicated by the double arrows in FIG. 2) in order to be able to align the equipotential bonding unit 1 relative to the cable 10 when in use. Any adjustability in space, both linear and rotary, can be provided. However, the equipotential bonding unit 1 can also be fixed (but preferably exchangeable) on the holder 5 .

The equipotential bonding unit 1, and thus also the at least one brush body 2 with the at least one contact bristle 3, can be arranged stationary relative to the moving cable 10. However, the equipotential bonding unit 1 can also be movably arranged in the cable-pulled conveyor device, for example on a moving component of the cable-pulled conveyor device.

The at least one contact bristle 3 is arranged facing the cable 10 . The distance between the at least one brush body 2 or the at least one contact bristle 3 and the cable 10 can be selected so that the at least one elastic contact bristle 3 nestles against the cable 10 in order to establish good electrical contact. After the contact bristle 3 is pressed against the rope 10 simply because of the elasticity of the contact bristle 3 itself, there is only very little wear on the contact bristle 3 and little mechanical stress on the rope 10. Apart from that, it doesn't matter if some of the contact bristles 3 are stronger wear out, since there are always enough contact bristles 3 in electrical contact with the rope 10 in the case of a contact pile. In this case, not all of the contact bristles 3 always have to make electrical contact with the cable 10 either.

However, it is not absolutely necessary for the at least one contact bristle 3 to touch the cable 10 in order to establish a potential equalization to a reference potential. The distance between the brush body 2 and the cable 10 can also be chosen so that there is no contact between the at least one contact bristle 3 or the bristle pile and the cable 10 . In this case, the at least one elastic contact bristle 3 would not have to be elastic either. In this case, equipotential bonding would occur when the potential difference between the potential point with reference potential and the cable 10 becomes so large that an electrical flashover occurs between the cable 10 and the at least one contact bristle 3 .

Because of the elastic contact bristle 3, it is also not necessary for the equipotential bonding unit 1 to be pressed against the cable 10, for example by means of a spring or another pressing mechanism. The equipotential bonding unit 1 thus preferably does not include any moving components and can therefore be constructed very simply. The grounding brush 1 can therefore also be used in particular with a cable 10 made of steel and plastic, as shown for example in FIG. 4, or only made of plastic. The rope 10 shown comprises a rope core 13 (made of steel and/or plastic), several strands 11 consisting of individual wires, and inserts 12 made of plastic, which are twisted to form the rope 10 . The inserts 12 made of plastic are not damaged on the surface by a potential equalization unit 1 according to the invention.

The electrical conductor 4 can connect the at least one electrically conductive contact bristle 3, for example via the brush body 2, to a potential point 14 with a defined electrical reference potential, with the reference potential being ground or any other electrical potential. Of course, several such potential points 14 with reference potential can also be provided in the cable-pulled conveyor device. However, the electrical connection does not necessarily have to be made by such a conductor 4 . The potential point 14 can be, for example, any component of the cable-pulled conveyor device that is at reference potential (e.g. grounded), for example in a cable car station. If the at least one contact bristle 3 is electrically conductively connected to the at least one brush body 2, then the brush body 2 can also be arranged directly on a component of the cable-pulled conveyor device that is at the reference potential.

Provision can also be made for a resistor R to be provided between the potential point 14 and the at least one contact bristle 3, as indicated in FIG. A desired potential of the cable 10 can thus be set despite potential equalization.

In principle, the equipotential bonding unit 1 can be arranged at any position in the area of the cable 10 . However, the equipotential bonding unit 1 is preferably arranged in such a way that the at least one contact bristle 3 is aligned from top to bottom and preferably rests against the cable 10 . In this way, in particular with a brush pile, it can be achieved that dirt cannot accumulate so easily between the contact bristles 3 . Possible advantageous positions of the equipotential bonding unit 1 in the area of the cable 10 are shown in FIG.

Tests have shown that with such a potential equalization unit 1, a safe and reliable electrical potential equalization of the moving rope 10 can be achieved over a large range of rope speeds, for example between 0 and 7 m/s as is usual with cable cars, in which an electrical charge on the rope 10 is discharged.

A heating device (not shown) can also be provided on the potential equalization unit 1 in order to counteract icing of the potential equalization unit 1 , in particular the at least one contact bristle 3 . This is particularly advantageous for a cable-pulled conveyor that is exposed to the external environmental conditions exposed, such as a cable car. The heating device can be designed electrically, for example.

Claims

patent claims

1. Arrangement for equipotential bonding of a moving cable (10) of a cable-pulled conveyor device with a defined electrical reference potential of the cable-pulled conveyor device, characterized in that an equipotential bonding unit (1) is provided, with at least one brush body (2) and with at least one electrically conductive brush body arranged therein Contact bristle (3) made of electrically conductive plastic, wherein the potential equalization unit (1) is arranged relative to the moving cable (10) in order to enable potential equalization between the at least one electrically conductive contact bristle (3) and the moving cable (10) and that the at least one electrically conductive contact bristle (3) with at least one potential point (14) is electrically conductively connected to the electrical reference potential.

2. Arrangement according to claim 1, characterized in that the at least one contact bristle (3) is elastic and the equipotential bonding unit (1) is arranged relative to the moving cable (10), so that the at least one elastic and electrically conductive contact bristle (3) moving rope (10) electrically contacted.

3. Arrangement according to claim 1, characterized in that the equipotential bonding unit (1) is arranged relative to the moving rope (10), so that the at least one electrically conductive contact bristle (3) is arranged at a distance from the rope (10).

4. Arrangement according to claim 1, characterized in that the at least one contact bristle (3) is electrically conductively connected to at least one electrical conductor (4) and the at least electrically conductive contact bristle (3) via the at least one electrical conductor (4) to the at least one potential point (14) of the cable-pulled conveyor device is electrically conductively connected

5. Arrangement according to claim 1, characterized in that the at least one brush body (2) is designed to be electrically conductive and the at least one contact bristle (3) is electrically conductively connected to the at least one brush body (2) and the at least one electrically conductive contact bristle ( 3) is electrically conductively connected via the brush body (2) to the at least one potential point (14) of the cable-pulled conveyor device.

6. Arrangement according to claim 4 and 5, characterized in that the at least one electrical conductor (4) is electrically conductively connected to at least one brush body (2).

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7. Arrangement according to one of claims 1 to 6, characterized in that the potential equalization unit (1) is arranged on a holder (5), wherein the potential equalization unit (1) is fixed to the holder (5) in the cable-pulled conveyor.

8. Arrangement according to claim 7, characterized in that the

Equipotential bonding unit (1) for aligning the equipotential bonding unit (1) relative to the cable relative to the bracket (5) is arranged adjustably.

9. Arrangement according to claim 7, characterized in that the holder (5) is arranged on a stationary or moving component of the cable-pulled conveyor.

10. Arrangement according to one of claims 1 to 8, characterized in that an electrical resistance (R) is provided between the at least one electrically conductive contact bristle (3) and the potential point (14).

11. Arrangement according to one of claims 1 to 10, characterized in that a heating device is provided on the equipotential bonding unit (1).

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