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EP-4742469-A1 - SUSPENSION DEVICE

EP4742469A1EP 4742469 A1EP4742469 A1EP 4742469A1EP-4742469-A1

Abstract

A suspension device (1) for suspending an object from an overhead power transmission line, comprising: - two gripping arms (10, 20) pivotally mounted to a base (5) and pivotable in relation to each other between a closed position and an open position; and - clamping jaws (11, 21) fixed to and carried by a respective one of the gripping arms. Each clamping jaw has a base part (30) with two flank sections (32a, 32b) projecting from the associated gripping arm on opposite sides thereof, wherein each flank section has a rear face (33) that is exposed to surrounding air. Each clamping jaw also has upper and lower fingers (36, 39) that are rigidly connected to and project obliquely upwards and downwards, respectively, from the base part (30), wherein each finger has a rear face (37) that is exposed to surrounding air.

Inventors

  • EVERTSSON, Johan

Assignees

  • Hammar, Lars

Dates

Publication Date
20260513
Application Date
20241111

Claims (15)

  1. A suspension device for suspending a sign or other object from an overhead power transmission line, the suspension device (1) comprising: - a base (5); - an attachment bracket (4, 4'), which is fixed to the base (5) and to which said object is attached or attachable; - a first gripping arm (10), which is pivotally mounted to the base (5) and pivotable in relation to the base (5) about a first pivot axis (A1), and a second gripping arm (20), which is pivotally mounted to the base (5) and pivotable in relation to the base (5) about a second pivot axis (A2) that is parallel to and located at a distance from the first pivot axis (A1); - a first clamping jaw (11) fixed to and carried by the first gripping arm (10) and a second clamping jaw (21) fixed to and carried by the second gripping arm (20), wherein the first and second gripping arms (10, 20), by pivoting about the respective pivot axis (A1, A2), are pivotable in relation to each other between an open position, in which the first and second gripping arms (10, 20), and thereby the first and second clamping jaws (11, 21), are pivoted away from each other to allow an overhead power transmission line (3) to be inserted in a space between the first and second clamping jaws (11, 21), and a closed position, in which the first and second gripping arms (10, 20), and thereby the first and second clamping jaws (11, 21), are pivoted towards each other to allow the first and second clamping jaws (11, 21) to grip an overhead power transmission line (3) received in the space between the first and second clamping jaws (11, 21) and thereby clamp the suspension device (1) to the overhead power transmission line; and - at least one spring member (6a) configured to act between the first and second gripping arms (10, 20) to urge them towards the closed position, wherein the first and second gripping arms (10, 20) are pivotable from the closed position towards the open position against the action of the at least one spring member (6a), characterized in: - that the first clamping jaw (11) comprises a base part (30), through which it is connected to the first gripping arm (10), wherein this base part (30) has a central section (31), a first flank section (32a) that is rigidly connected to the central section (31) and projects laterally from the first gripping arm (10) on a first side thereof and an opposite second flank section (32b) that is rigidly connected to the central section (31) and projects laterally from the first gripping arm (10) on an opposite second side thereof, wherein these first and second flank sections (32a, 32b) have a respective rear face (33) that is exposed to surrounding air and a respective front face (34) that is substantially flush with a front face (35) of the intermediate central section (31), and wherein the front face (35) of the central section (31), the front face (34) of the first flank section (32a) and the front face (34) of the second flank section (32b) together form a first primary clamping surface (15) that extends substantially in parallel to the first pivot axis (A1); - that the second clamping jaw (21) comprises a base part (30), through which it is connected to the second gripping arm (20), wherein this base part (30) has a central section (31), a first flank section (32a) that is rigidly connected to the central section (31) and projects laterally from the second gripping arm (20) on a first side thereof and an opposite second flank section (32b) that is rigidly connected to the central section (31) and projects laterally from the second gripping arm (20) on an opposite second side thereof, wherein these first and second flank sections (32a, 32b) have a respective rear face (33) that is exposed to surrounding air and a respective front face (34) that is substantially flush with a front face (35) of the intermediate central section (31), wherein the front face (35) of the central section (31), the front face (34) of the first flank section (32a) and the front face (34) of the second flank section (32b) together form a second primary clamping surface (25) that extends substantially in parallel to the second pivot axis (A2), and wherein, in the closed position of the gripping arms (10, 20), the first and second primary clamping surfaces (15, 25) are configured to face each other and apply pressure against an overhead power transmission line (3) received in the space between the first and second clamping jaws (11, 21) by pressing against said overhead power transmission line (3) from opposite sides thereof; - that the first clamping jaw (11) is provided with two or more upper fingers (36) that are rigidly connected to and project obliquely upwards from the base part (30) of the first clamping jaw (11), each one of these upper fingers (36) having a rear face (37) that is exposed to surrounding air and an opposite front face (38) that slants forwards beyond the first primary clamping surface (15); - that the second clamping jaw (21) is provided with one or more upper fingers (36) that are rigidly connected to and project obliquely upwards from the base part (30) of the second clamping jaw (21), each one of these upper fingers (36) having a rear face (37) that is exposed to surrounding air and an opposite front face (38) that slants forwards beyond the second primary clamping surface (25), wherein the upper fingers (36) on the first and second clamping jaws (11, 21) are arranged in an interleaved configuration, such that said one or more upper fingers (36) on the second clamping jaw (21) are configured to interleave with said two or more upper fingers (36) on the first clamping jaw (11) in the closed position of the gripping arms (10, 20); - that the front faces (38) of said upper fingers (36) on the first and second clamping jaws (11, 21) form upper secondary clamping surfaces capable of applying pressure against an overhead power transmission line (3) received in the space between the first and second clamping jaws (11, 21) by pressing against it; - that the first clamping jaw (11) is provided with two or more lower fingers (39) that are rigidly connected to and project obliquely downwards from the base part (30) of the first clamping jaw (11), each one of these lower fingers (39) having a rear face (40) that is exposed to surrounding air and an opposite front face (41) that slants forwards beyond the first primary clamping surface (15); - that the second clamping jaw (21) is provided with two or more lower fingers (39) that are rigidly connected to and project obliquely downwards from the base part (30) of the second clamping jaw (21), each one of these lower fingers (39) having a rear face (40) that is exposed to surrounding air and an opposite front face (41) that slants forwards beyond the second primary clamping surface (25), wherein the lower fingers (39) on the first and second clamping jaws (11, 21) are arranged in an interleaved configuration, such that said two or more lower fingers (39) on the second clamping jaw (21) are configured to interleave with said two or more lower fingers (39) on the first clamping jaw (11) in the closed position of the gripping arms (10, 20); and - that the front faces (40) of said lower fingers (39) on the first and second clamping jaws (11, 21) form lower secondary clamping surfaces capable of applying pressure against an overhead power transmission line (3) received in the space between the first and second clamping jaws (11, 21) by pressing against it.
  2. A suspension device according to claim 1, characterized in that cooling fins or cooling ribs (44) are provided on the rear faces (33) of the first and second flank sections (32a, 32b) of the base part (30) of the first clamping jaw (11) and on the rear faces (33) of the first and second flank sections (32a, 32b) of the base part (30) of the second clamping jaw (21).
  3. A suspension device according to claim 1 or 2, characterized in: - that the base part (30) and the upper and lower fingers (36, 39) of the first clamping jaw (11) are formed in one piece; and - that the base part (30) and the upper and lower fingers (36, 39) of the second clamping jaw (21) are formed in one piece.
  4. A suspension device according to any of claims 1-3, characterized in: - that the first clamping jaw (11) is releasably fixed to the first gripping arm (10), preferably by means of a snap-fit connection, wherein the base part (30) of the first clamping jaw (11) is configured to bear against a support surface (16) on the first gripping arm (10) through a rear face of the central section (31) of this base part (30); and - that the second clamping jaw (21) is releasably fixed to the second gripping arm (20), preferably by means of a snap-fit connection, wherein the base part (30) of the second clamping jaw (21) is configured to bear against a support surface (26) on the second gripping arm (20) through a rear face of the central section (31) of this base part (30).
  5. A suspension device according to claim 4, characterized in that the base part (30) of each one of the first and second clamping jaws (11, 21) has a plate-like structure.
  6. A suspension device according to claim 4 or 5, characterized in that cooling fins or cooling ribs (44) are provided on the rear face of the central section (31) of the base part (30) of the first clamping jaw (11) and on the rear face of the central section (31) of the base part (30) of the second clamping jaw (21).
  7. A suspension device according to any of claims 1-6, characterized in that each one of the first and second primary clamping surfaces (15, 25) is covered by a layer (48) of elastomeric material, preferably in the form of high-temperature silicone rubber.
  8. A suspension device according to claim 7, characterized in that each one of the upper and lower secondary clamping surfaces is covered by a layer (48) of elastomeric material, preferably in the form of high-temperature silicone rubber.
  9. A suspension device according to any of claims 1-8, characterized in that each one of the first and second clamping jaws (11, 21) is provided with at least three such upper fingers (36) distributed along an upper edge of the base part (30) of the clamping jaw (11 ,21).
  10. A suspension device according to any of claims 1-9, characterized in that each one of the first and second clamping jaws (11, 21) is provided with at least three such lower fingers (39) distributed along a lower edge of the base part (30) of the clamping jaw (11, 21).
  11. A suspension device according to any of claims 1-10, characterized in: - that the first and second gripping arms (10, 20) are made of a first plastic material, such as PA66 or PA46; and - that the base part (30) and the upper and lower fingers (36, 39) of the first and second clamping jaws (11, 21) are made of a second plastic material with higher heat resistance than said first plastic material, such as PA66-HT, PPS or PEEK.
  12. A suspension device according to any of claims 1-11, characterized in that the suspension device (1) comprises at least one gear mechanism (17a), which comprises a first gear member (18a) rigidly connected to the first gripping arm (10) and a second gear member (19a) rigidly connected to the second gripping arm (20), wherein said first and second gear members (18a, 19a) are in engagement with each other and are configured to be rotated in relation to each other when the gripping arms (10, 20) are pivoted in relation to each other.
  13. A suspension device according to any of claims 1-12, characterized in that the suspension device (1) comprises a spacer plate (8) that is rigidly connected to the base (5) and that extends upwards from the base (5) substantially perpendicularly to the first and second pivot axes (A1, A2), wherein, in the closed position of the gripping arms (10, 20), the spacer plate (8) extends into an interspace between one of the lower fingers (39) on the first clamping jaw (11) and one of the lower fingers (39) on the second clamping jaw (21), and wherein an upper edge (9) on the spacer plate (8) is configured to be exposed in the space between the first and second clamping jaws (11, 21) in the open position of the gripping arms (10, 20) to thereby allow the spacer plate (8) to form a lower support for an overhead power transmission line (3) received in this space.
  14. A suspension device according to any of claims 1-13, characterized in: - that said spring member (6a) constitutes a first spring member of the suspension device (1); - that the suspension device (1) also comprises a second spring member (6b) that is configured to act between the first and second gripping arms (10, 20) to urge them towards the closed position, wherein the first and second gripping arms (10, 20) are pivotable from the closed position towards the open position against the action of the second spring member (6b); and - that the first spring member (6a) and the second spring member (6b) are arranged in parallel with each other on opposite sides of the base (5).
  15. A suspension device according to any of claims 1-14, characterized in: - that each one of said first and second flank sections (32a, 32b) of the base part (30) of the first clamping jaw (11) constitutes a cantilever flank section; and - that each one of said first and second flank sections (32a, 32b) of the base part (30) of the second clamping jaw (21) constitutes a cantilever flank section

Description

FIELD OF THE INVENTION AND PRIOR ART The present invention relates to a suspension device according to the preamble of claim 1 for suspending a sign or other object from an overhead power transmission line. The suspension device according to the invention may for instance be used for suspending a sign, a flag or a bird-scaring device from an overhead power transmission line. A suspension device according to the preamble of claim 1 is previously known from EP 2 427 877 B1. The different parts of a suspension device of this type, except for the tension springs, are typically made of plastic material. When clamped to an overhead power transmission line, the suspension device will be exposed to heat from the overhead power transmission line and must be capable of withstanding this heat without being degraded. Standard overhead power transmission lines used for high-voltage power transmission typically operate at temperatures up to 90°C under normal conditions. A suspension device of the type disclosed in EP 2 427 877 B1 can withstand such temperatures even when made of relatively simple and inexpensive plastic materials. However, if a suspension device of the type disclosed in EP 2 427 877 B1 is to be clamped to overhead power transmission lines used for extra-high or ultra-high voltage levels, the suspension device has to be made of more temperature-resistant and expensive plastic materials to withstand the higher operating temperatures of such overhead power transmission lines, which will make the suspension device relatively expensive to produce. OBJECT OF THE INVENTION The object of the present invention is to provide a suspension device of the above-mentioned type with new and favourable design. SUMMARY OF THE INVENTION According to the present invention, said object is achieved by means of a suspension device having the features defined in claim 1. The suspension device according to the invention comprises: a base;an attachment bracket, which is fixed to the base and to which an object, such as a sign or the similar, is attached or attachable;a first gripping arm, which is pivotally mounted to the base and pivotable in relation to the base about a first pivot axis, and a second gripping arm, which is pivotally mounted to the base and pivotable in relation to the base about a second pivot axis that is parallel to and located at a distance from the first pivot axis;a first clamping jaw fixed to and carried by the first gripping arm and a second clamping jaw fixed to and carried by the second gripping arm, wherein the first and second gripping arms, by pivoting about the respective pivot axis, are pivotable in relation to each other between an open position, in which the first and second gripping arms, and thereby the first and second clamping jaws, are pivoted away from each other to allow an overhead power transmission line to be inserted in a space between the first and second clamping jaws, and a closed position, in which the first and second gripping arms, and thereby the first and second clamping jaws, are pivoted towards each other to allow the first and second clamping jaws to grip an overhead power transmission line received in the space between the first and second clamping jaws and thereby clamp the suspension device to the overhead power transmission line; andat least one spring member configured to act between the first and second gripping arms to urge them towards the closed position, wherein the first and second gripping arms are pivotable from the closed position towards the open position against the action of the at least one spring member. The first clamping jaw comprises a base part, through which it is connected to the first gripping arm, wherein this base part has a central section, a first flank section that is rigidly connected to the central section and projects laterally from the first gripping arm on a first side thereof and an opposite second flank section that is rigidly connected to the central section and projects laterally from the first gripping arm on an opposite second side thereof, wherein these first and second flank sections have a respective rear face that is exposed to surrounding air and a respective front face that is substantially flush with a front face of the intermediate central section, and wherein the front face of the central section, the front face of the first flank section and the front face of the second flank section together form a first primary clamping surface that extends substantially in parallel to the first pivot axis. In the corresponding manner, the second clamping jaw comprises a base part, through which it is connected to the second gripping arm, wherein this base part has a central section, a first flank section that is rigidly connected to the central section and projects laterally from the second gripping arm on a first side thereof and an opposite second flank section that is rigidly connected to the central section and projects laterally fr