Cable clamping device and cable sealing sleeve

Abstract

A clamping device (24) for a cable clamp (2) or a cable gland is disclosed. The clamping device comprises a bolt (22) having a first threaded portion; a nut (26) having a second threaded portion adapted to engage with the first threaded portion to apply a clamping force to the cable (4); and an indication device (28) providing a visual indication that the clamping force exceeds a first predetermined level.

Description

Technical Field

[0001] The present invention relates to a cable clamping device and a cable gland, and particularly, but not limited to, a cable clamp for clamping a cable or a cable gland for clamping an outer sheath or armor layer of a cable. Background Art

[0002] Cable clamps are used to clamp multiple cables together and secure the cables in place when a fault current causes them to violently separate. The cable clamp typically includes a main body having a first and second hingedly connected body. Each of the first and second body parts has a flange, and the flanges are clamped together by a bolt inserted through a hole in the flange and a nut attached to the bolt. The nut and bolt are secured together by intermeshing threads. The clamping force applied to the cable is adjusted by the torque applied to the nut, thereby adjusting the spacing between the flanges of the first and second body parts.

[0003] Known cable clamps have the following disadvantages: if the clamping force applied to the cable is too great, the insulation material on the cable's outer surface may be damaged; if the clamping force applied is insufficient, the cable clamp may not effectively secure the cable in place during a fault current. In addition to fault current situations, insufficient clamping force can also cause the cable to slip within the cable clamp when subjected to axial loads (e.g., vertical cable installations in shafts).

[0004] Cable glands are used to connect electrical cables to housings and typically comprise a gland body having a clamping device for clamping a compressible seal so that the seal clamps against the outer jacket of the cable and / or for clamping against the armour of the cable.

[0005] Known cable glands have the following disadvantages: if insufficient clamping force is applied, the cable gland may not function properly and when inspecting the cable gland it may be difficult to determine whether sufficient clamping force has been applied. Summary of the Invention

[0006] Preferred embodiments are directed to overcoming one or more of the above-mentioned disadvantages.

[0007] According to the invention of the present application, there is provided a cable clamping device for encircling and clamping at least one cable. The cable clamping device comprises: a first body portion pivotally mounted to a second body portion to form a body suitable for engaging at least one cable; and a clamping device that applies a clamping force to the or each cable by urging the first and second body portions toward each other, wherein the clamping device comprises: a first component having a first threaded portion; a second component having a second threaded portion adapted to engage with the first threaded portion to urge the first body portion and the second body portion toward each other; and Indicator means is provided for providing a visual indication that the clamping force exceeds a first predetermined level.

[0008] By providing an indicator means for providing a visual indication that the clamping force exceeds the first predetermined level, it is advantageous that it can be easily determined that sufficient clamping force has been applied, thereby making the cable clamping device more reliable in operation.

[0009] The indicator device may comprise at least one first indicator portion. The indicator device provides a visual indication by exposing at least part of the at least one first indicator portion so that it is visible from outside the cable clamping device in use.

[0010] Providing an indicator device which provides a visual indication by exposing at least part of the at least one first indicator portion so that it is visible externally of the cable clamping device in use has the advantage that operation of the indicator device is simplified when the first component is mounted to the second component.

[0011] The indicator device may further comprise first covering means for covering the at least one first indicator portion to an extent that depends on the clamping force.

[0012] Providing a first covering device that covers at least one first indicator portion to a degree dependent on the clamping force has the advantage of being able to estimate the clamping force and avoid applying excessive clamping force, thereby improving operational reliability of the cable clamping device.

[0013] The first covering device and the first indicator portion are relatively movable, and the cable clamping device may further include a first actuating device for urging the at least one first indicator portion to move relative to the first covering device to a state where the exposure degree of the first indicator portion is maximized.

[0014] The indicating means may be adapted to provide a visual indication that the clamping force exceeds a second predetermined level. The second predetermined level is higher than the first predetermined level.

[0015] This has the advantage that excessive clamping forces can be avoided, thereby ensuring a more reliable operation of the cable clamping device.

[0016] The cable clamping device may further comprise preventing means for preventing the clamping force from exceeding a second predetermined level.

[0017] This has the advantage that excessive clamping forces are avoided, thereby ensuring a more reliable operation of the cable clamp.

[0018] The preventing means may be adapted to limit movement of the first component relative to the second component.

[0019] The preventing means comprises at least one third component for enabling movement of the first component relative to the second component and preventing movement of the first component relative to the second component when the clamping force exceeds a second predetermined level.

[0020] Providing at least one third component for enabling movement of the first component relative to the second component and preventing movement of the first component relative to the second component when the clamping force exceeds a second predetermined level has the advantage that construction and operation of the cable clamping device are simplified.

[0021] The at least one third component may be adapted to move the first component relative to the second component in such a manner that at least one projection and / or recess on the third component engages with a corresponding recess and / or projection on the first component or the second component, wherein the projection and / or recess is unable to transmit torque via the corresponding recess and / or projection when the clamping force exceeds a second predetermined level.

[0022] The preventing means may be adapted to limit movement of the first component relative to the second component by abutment of the first component and the second component.

[0023] This is advantageous in that the abutment of the first component against the second component can simultaneously provide a visual indication that sufficient clamping force has been applied and avoid the application of excessive clamping force.

[0024] According to another aspect of the present application, there is provided a cable clamping device for encircling and clamping at least one cable. The cable clamping device comprises: a first component pivotally mounted to a second component to form a body adapted to engage at least one cable; and clamping means for applying a clamping force to the or each cable by urging the first and second components toward each other, wherein the clamping device includes prevention means for preventing application of a clamping force exceeding a predetermined level to the or each cable.

[0025] This has the advantage that excessive clamping forces are avoided, thereby ensuring a more reliable operation of the cable clamp.

[0026] The preventing means may be adapted to limit movement of the first component relative to the second component.

[0027] The preventing means may comprise at least one third component for enabling movement of the first component relative to the second component and preventing movement of the first component relative to the second component when the clamping force exceeds a predetermined level.

[0028] Providing at least one third component for enabling movement of the first component relative to the second component and preventing movement of the first component relative to the second component when the clamping force exceeds a second predetermined level has the advantage that construction and operation of the cable clamping device are simplified.

[0029] The at least one third component may be adapted to move the first component relative to the second component in such a manner that at least one projection and / or recess on the third component engages with a corresponding recess and / or projection on the first component or the second component, wherein the projection and / or recess is unable to transmit torque via the corresponding recess and / or projection when the clamping force exceeds a second predetermined level.

[0030] The cable clamping device may further comprise an indicator means for providing a visual indication that the clamping force exceeds a further predetermined level.

[0031] The indicating device comprises at least one first indicating portion, the indicating device providing a visual indication in such a way that at least a portion of the at least one first indicating portion is exposed such that the portion is visible from the outside of the cable clamping device in use.

[0032] The indicator device may further comprise first covering means for covering the at least one first indicator portion to an extent that depends on the clamping force.

[0033] The first covering device and the first indicator portion are relatively movable, and the cable clamping device may further include a first actuating device for urging the at least one first indicator portion to move relative to the at least one first covering device to a state where the exposure degree of the first indicator portion is maximized.

[0034] The indicating means may be adapted to provide a visual indication that the clamping force exceeds a further predetermined level, wherein the further predetermined level is lower than the predetermined level.

[0035] According to another aspect of the present application, a cable gland is provided. The cable gland is used to clamp a cable passing through the cable gland and comprises: a first housing portion having a first threaded portion; a second housing portion having a second threaded portion adapted to engage the first threaded portion to move the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland; and A clamping device adapted to apply a clamping force to a cable, wherein the clamping device includes at least one resilient member positioned between a first housing portion and a second housing portion such that movement of the second housing portion relative to the first housing portion compresses the at least one resilient member in a direction generally parallel to a longitudinal axis of the cable gland, thereby causing the cable gland to provide a visual indication that the clamping force exceeds a first predetermined level.

[0036] By providing a visual indication that the clamping force exceeds the first predetermined level, it is advantageous that it can be easily determined that sufficient clamping force has been applied, thereby making the cable gland more reliable in operation.

[0037] The cable gland may further comprise at least one first indicator portion, wherein the cable gland provides a visual indication in that compression of the at least one resilient member exposes at least part of the at least one first indicator portion so that it is visible outside the cable clamping device in use.

[0038] The visual indication may be provided by causing at least part of the at least one first indicator to protrude from the first housing portion or the second housing portion.

[0039] The cable gland may be adapted to provide a visual indication that the clamping force exceeds a second predetermined level, wherein the second predetermined level is higher than the first predetermined level.

[0040] The cable gland may provide a visual indication by abutting the first housing portion against the second housing portion.

[0041] At least one of the resilient members may include a corresponding seal for engaging a surface of the cable, wherein compression of the seal causes the seal to sealingly engage the surface of the cable.

[0042] The at least one resilient member may comprise a respective compression spring.

[0043] The cable gland may be adapted to clamp the armour of a cable passing through the cable gland.

[0044] The cable gland may further comprise preventing means for preventing the clamping force from exceeding a second predetermined level.

[0045] The preventing means may be adapted to limit movement of the first housing part relative to the second housing part.

[0046] The preventing means may comprise at least one third housing portion for enabling movement of the first housing portion relative to the second housing portion and preventing movement of the first housing portion relative to the second housing portion when the clamping force exceeds a second predetermined level.

[0047] At least one third housing part is suitable for moving the first housing part relative to the second housing part in such a manner that at least one protrusion and / or groove on the third housing part engages with a corresponding groove and / or protrusion on the first housing part or the second housing part, wherein the protrusion and / or groove cannot transmit torque via the corresponding groove and / or protrusion when the clamping force exceeds a second predetermined level.

[0048] The preventing means may be adapted to limit movement of the first housing part relative to the second housing part by abutment of the first housing part with the second housing part.

[0049] According to another aspect of the present application, a cable gland is provided. The cable gland is used to clamp a cable passing through the cable gland and comprises: a first housing portion having a first threaded portion; a second housing portion having a second threaded portion adapted to engage the first threaded portion to move the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland; a clamping device adapted to apply a clamping force to the cable as a result of movement of the second housing portion relative to the first housing portion; and A prevention device for preventing the clamping force from exceeding a predetermined level and comprising at least one resilient member located between the first shell part or the second shell part and the clamping device, so that movement of the second shell part relative to the first shell part causes the at least one resilient member to be compressed in a direction substantially parallel to the longitudinal axis of the cable gland, and before the clamping force exceeds the predetermined level, the first shell part abuts the second shell part to prevent further movement of the second shell part relative to the first shell part.

[0050] This has the advantage that excessive clamping forces are avoided, thereby ensuring a more reliable operation of the cable clamp.

[0051] The clamping device may be adapted to apply a clamping force to the armour of the cable.

[0052] The clamping device may include a first clamping portion and a second clamping portion, the second clamping portion being adapted to surround at least a portion of the first clamping portion to apply a clamping force to the armor layer of the cable due to movement of the second housing portion relative to the first housing portion in a direction substantially parallel to the longitudinal axis of the cable gland.

[0053] The first clamping portion may be adapted to engage the first housing portion or the at least one resilient member, and the second clamping portion may be adapted to engage the second housing portion or the at least one resilient member.

[0054] The cable gland may further include at least one seal for engaging an outer surface of the cable as a result of movement of the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland.

[0055] The cable gland may further comprise at least one actuating portion for urging the at least one seal into engagement with an outer surface of the cable by sliding engagement with at least one surface of the second body portion that is inclined relative to a longitudinal axis of the cable.

[0056] The cable gland may be adapted to provide a visual indication that sufficient clamping force has been applied to the cable.

[0057] The visual indication may be provided by abutment of the first housing portion with the second housing portion.

[0058] The cable gland may further comprise at least one first indicator portion, wherein the cable gland provides a visual indication in that compression of the at least one resilient member exposes at least part of the at least one first indicator portion so that it is visible outside the cable clamping device in use.

[0059] The visual indication may be provided by causing at least part of the at least one first indicator to protrude from the first housing portion or the second housing portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Preferred embodiments will now be described by way of example and not limitation with reference to the accompanying drawings, in which:

[0061] Figure 1 is a side cross-sectional view of the cable clamp of the first embodiment when the clamping device is in an uncompressed state;

[0062] Figure 2 yes Figure 1 A side cross-sectional view of the clamping device in a compressed state;

[0063] Figure 3 yes Figure 2 A perspective view of the clamping device in an uncompressed state;

[0064] Figure 4 yes Figure 2 A three-dimensional view of the clamping device in a compressed state;

[0065] Figure 5 yes Figure 2 A three-dimensional diagram of the clamping device in an over-compressed state;

[0066] Figure 6 is a partially cutaway perspective view of the clamping device in the second embodiment in a compressed state;

[0067] Figure 7 yes Figure 6 Exploded view of the clamping device in;

[0068] Figure 8 yes Figure 6 A side cross-sectional view of the ratchet mechanism of the clamping device;

[0069] Figure 9 yes Figure 6 A side view of the clamping device in a compressed state;

[0070] Figure 10 yes Figure 6 A side view of the clamping device in an uncompressed state;

[0071] Figure 11 is a partial cross-sectional side view of a conventional cable gland when the clamping device is in an uncompressed state;

[0072] Figure 12 yes Figure 11 A partial cross-sectional side view of a conventional cable gland in FIG, wherein the clamping device is in a compressed state;

[0073] Figure 13 is a partial cross-sectional side view of the cable gland in the third embodiment when the clamping device is in an uncompressed state;

[0074] Figure 14 yes Figure 13 A partial cross-sectional side view of the cable gland in the embodiment of the present invention with the clamping device in a compressed state;

[0075] Figure 15 yes Figure 13 A side view of the cable gland in the clamping device in the uncompressed state;

[0076] Figure 16 yes Figure 15 A side view of the compression spring in a compressed state;

[0077] Figure 17 is a partial cross-sectional side view of a cable gland according to a fourth embodiment with the clamping device in an uncompressed state;

[0078] Figure 18 yes Figure 17 A partial cross-sectional side view of the cable gland in the embodiment of the present invention with the clamping device in a compressed state;

[0079] Figure 19 yes Figure 17 A perspective view of a ratchet component of a cable gland in FIG.

[0080] Figure 20 yes Figure 17 A perspective view of the outer nut of the cable gland in FIG.

[0081] Figure 21 is a partial cross-sectional side view of the cable gland in the fifth embodiment when the clamping device is in an uncompressed state;

[0082] Figure 22 yes Figure 21 A partial cross-sectional side view of the cable gland in FIG. 1 with the clamping device in a compressed state;

[0083] Figure 23 is a partial cross-sectional side view of a portion of a cable gland according to a sixth embodiment with the clamping device in an uncompressed state;

[0084] Figure 24 yes Figure 23 A partial cross-sectional side view of a portion of the cable gland in FIG. 1 with the clamping device in a compressed state;

[0085] Figure 25 yes Figure 23 A three-dimensional view of the clamping portion of the cable gland in an uncompressed state;

[0086] Figure 26 yes Figure 25 A three-dimensional diagram of the clamping portion in a compressed state;

[0087] Figure 27 is a partial cross-sectional side view of a portion of a cable gland in a seventh embodiment with the clamping device in an uncompressed state; and

[0088] Figure 28 yes Figure 27 A partially cutaway side view of a portion of a cable gland in FIG. 1 with the clamping device in a compressed state. DETAILED DESCRIPTION

[0089] See also Figures 1 to 5 A cable clamp 2 for securing three cables 4 in a trilobal arrangement includes a main body 6 comprising a first main body portion 8 pivotally connected to a second main body portion 12 via a hinge 10. The first and second main body portions 8 and 12 have flanges 14 and 16, respectively, each provided with a hole 18 and a hole 20, respectively, for receiving a bolt 22 of a clamping device 24. The clamping device 24 also includes a fastening nut 26 and an indicator device in the form of an indicator 28. The indicator 28 includes a first indicator portion 30 and a cover member 32 adapted to slidably receive the first indicator portion 30. The indicator portion 30 is urged outwardly away from the cover member 32 by an actuating device in the form of a compression spring 34. The extent to which the indicator portion 30 protrudes from the cover member 32 is determined by the amount of compression of the compression spring 34, which in turn depends on the clamping force applied to the cable 4 by the nut 26 and the bolt 22.

[0090] like Figures 3 to 5 As shown, the first indicator portion 30 includes a visual indicator in the form of a first color region 36 and a second color region. In the uncompressed state of the indicator 28, both color regions 36 and 38 are visible from outside the indicator 28. As the nut 26 is tightened on the bolt 22, if the clamping force reaches a first predetermined value, the first indicator portion 30 is positioned within the cover portion 32 to such an extent that only the first color region 36 is visible, while the second color region 38 is obscured by the cover portion 32. This indicates that sufficient clamping force is being applied to the cable 4, but not excessive. As the nut 26 is further tightened on the bolt 22, the compression spring 34 further compresses, causing the indicator portion 30 to be positioned further within the cover portion 32, so that neither the first color region 36 nor the second color region is visible. This indicates that excessive clamping force is being applied.

[0091] See also Figures 6 to 10 , shows a second embodiment of the clamping device 124, wherein Figures 1 to 5 Components common to the embodiments are denoted by the same reference numerals, but increased by 100. The clamping device 124 includes an internally threaded nut 126 for engaging with the bolt 22, an indicator portion 130 and a compression spring 134 received in the annular groove 40 on the nut 126, such that the compression spring 134 pushes the nut 126 away from the flange 14, thereby making the indicator portion 130 visible when the nut has not moved far enough along the bolt 22 (corresponding to a sufficiently high applied clamping force).

[0092] The nut 126 is prevented from rotating relative to the bolt 22 by a means in the form of an outer nut 42. The outer nut 42 is provided with a resilient protrusion 44 that engages with an axial groove 46 in the nut 126, and the axial groove 46 has an inclined side surface 48. When the torque applied to the nut 126 reaches a second predetermined level (which is higher than the first predetermined level), the resilient protrusion 44 on the outer nut 42 bends and slides out along the inclined side surface 48, disengaging from the groove 46 in the nut 126. This causes the outer nut 42 to rotate relative to the nut 126 without being able to apply further torque to the nut 126, thereby preventing excessive clamping force from being applied to the cable 4.

[0093] When the clamping force applied to the cable 4 is insufficient, the nut 126 can be pushed outwardly away from the flange 14 by the compression spring 134, making at least a portion of the indicator 130 visible to the user of the clamping device 124. This indicates to the user that the currently applied clamping force is insufficient for proper operation of the cable clamp 2. As the nut 126 is tightened against the bolt 22, the compression spring 134 is sufficiently compressed that the indicator 130 is no longer visible to the user of the clamping device 124, indicating that sufficient clamping force has been applied to the cable 4.

[0094] When the clamping force is increased by further rotating the outer nut 42, the torque applied to the outer nut 42 is too large, causing the elastic protrusion 44 on the outer nut 42 to bend and slide out of the groove 46 on the nut 126, which causes the outer nut 42 to rotate relative to the nut 126 without being able to apply more torque to the nut 126.

[0095] Reference Figure 11 and Figure 12, shows a conventional cable gland 50 for mounting to a cable 4. The cable gland 2 includes a gland body having a first component (in the form of an inlet piece 52) for connection to a housing (not shown), a second component (in the form of a main body 54), and an external nut 56. The cable gland includes a first clamping device 58 for clamping the armor 60 of the cable 4. The first clamping device 58 has a generally frustoconical inner clamping portion 62 and a generally annular outer clamping ring 64. The clamping ring 64 surrounds the clamping portion 62 to clamp the armor 60 of the cable 4 between the clamping ring 64 and the clamping portion 62. The clamping portion 62 abuts an abutment surface 66 at the end of the inlet piece 52, and the clamping ring 64 abuts an abutment surface 68 on the main body 54. The armor 60 is clamped between the clamping portion 62 and the clamping ring 64 by the engagement of an internally threaded surface 70 of the main body 54 with an externally threaded surface 72 of the inlet piece 52.

[0096] The second clamping device 74 is used to apply a clamping force to the compression seal 76. By engaging the internal threaded surface 84 of the external nut 56 with the external threaded surface 86 of the main body 54, the seal 76 is compressed between the end surface 78 of the compression sleeve 80 located in the external nut 56 and the end surface 82 of the main body 54. The compression of the seal 76 causes the seal 76 to clamp the outer jacket 88 of the cable 4.

[0097] Figure 11 and Figure 12 The conventional cable gland 50 shown has two significant disadvantages. First, because the final position of the clamping ring 64 relative to the clamping portion 62 depends on the thickness of the armor 60, the final position of the main body 54 relative to the entry piece 52 varies, making it difficult to determine whether sufficient clamping force is being applied to the armor 60 by inspecting the gland 50. Second, regardless of the degree to which the compression seal 76 is compressed, the degree to which the compression sleeve 80 protrudes from the outer nut 56 remains the same, making it difficult to determine whether sufficient clamping force is being applied to the outer jacket 88 of the cable 4 by inspecting the gland 50.

[0098] Figures 13 to 16 A third embodiment of a cable gland 150 is shown, wherein the Figure 11 and Figure 12 Components common to the cable glands shown are denoted by the same reference numerals but with an increment of 100. The cable gland 150 has a first clamping device 158 for clamping the armor 60 of the cable 4, the first clamping device comprising an inner clamping portion 162 abutting against an abutment surface 166 on the inlet piece 152, an outer clamping ring 164, and a compression spring 90 acting between the clamping ring 164 and the abutment surface 168 on the gland body 154. Therefore, when the body 154 is screwed onto the inlet piece to clamp the armor 60 between the clamping ring 164 and the clamping portion 162, if the clamping ring 164 reaches a position such as Figure 14In the maximum downward position shown, regardless of the final position of the clamping ring 164 determined by the thickness of the armor layer 60, the body portion 154 can continue to move up and down on the inlet piece 152 due to the engagement of the internal threaded surface 170 of the main body portion 154 with the external threaded surface 172 of the inlet piece 152. This process is achieved by the compression of the compression spring 90 until the end surface 92 of the main body portion 154 abuts the flange 94 on the inlet piece 152. This provides a visual indication that sufficient clamping force has been applied to the armor layer 60. In addition, the abutment of the end surface 92 of the main body portion 154 with the flange 94 of the inlet piece 152 prevents further movement of the clamping ring 164 relative to the clamping portion 162, thereby preventing excessive clamping force from being applied to the armor layer 60.

[0099] The cable gland 150 further includes a second clamping device 174 for clamping the compression seal 176 between an end face 182 of the main body 154 and an end face 178 of a compression sleeve 180 located within the external nut 156 by engaging an internal threaded surface 184 of the external nut 156 with an external threaded surface 186 of the main body 154, thereby clamping the outer jacket 88 of the cable 4. The compression sleeve 180 is slidably mounted within the external nut 156 against the force of a compression spring 96. An indicator portion in the form of a colored region 98 is provided on the outer surface of the compression sleeve 180. When sufficient clamping force is applied to the compression seal 176 to cause it to displace radially inwardly to apply sufficient clamping force to the outer jacket 88 of the cable 4, the colored region 98 of the compression sleeve 180 protrudes from the end of the external nut 156, providing a visual indication to an inspector that sufficient clamping force has been applied.

[0100] Reference Figures 17 to 20 , shows a fourth embodiment of a cable gland 250, wherein Figures 13 to 16 Components common to the illustrated embodiments are denoted by the same reference numerals, but increased by 100. The cable gland has a first clamping device 258 for clamping the armour 60 of the cable 4, and a second clamping device 274 for clamping the outer jacket 88 of the cable 4.

[0101] The first clamping device 258 includes a clamping portion 262 and a clamping ring 264 that surrounds the clamping portion 262 to clamp the armor layer 60 of the cable 4 between the clamping ring 264 and the clamping portion 262. The clamping portion 262 abuts against an abutment surface 266 at the end of the inlet piece 252, and the clamping ring 264 abuts against an abutment surface 268 on the main body 254. The first clamping device 258 is provided with a prevention device in the form of a ratchet member 242 to prevent the first clamping device 258 from applying excessive clamping force to the armor layer 60. The ratchet member 242 has an internally threaded surface 270 that engages with an externally threaded surface 272 on the inlet piece 252 and has a resilient protrusion 244 extending from its outer surface. The resilient protrusion 244 engages with a groove 246 on the inner surface of the main body 254.

[0102] Rotation of the main body 254 relative to the inlet piece 252 applies a clamping force to the armor 60 of the cable 4. As long as the applied torque is less than a second predetermined level, the protrusions 244 on the ratchet member 242 engage with the grooves 246 on the inner surface of the main body 254, causing the ratchet member 242 to rotate with the main body 254. This, in turn, causes the threaded surface 270 on the inner surface of the ratchet member 242 to engage with the threaded surface 272 on the outer surface of the inlet piece 252, thereby axially moving the main body 254 relative to the inlet piece 252 and clamping the armor 60 between the clamping ring 264 and the clamping portion 262. When the armor 60 is fully clamped between the clamping ring 264 and the clamping portion 262, application of the second predetermined level of torque causes the protrusions 244 on the ratchet member 242 to slide out of the grooves 246 on the main body 254, allowing the main body 254 to rotate relative to the ratchet member 242 and preventing further torque from being applied by the first clamping device 258. When the main body portion 254 is rotated relative to the ratchet member 242, this indicates to the user that the clamping device 258 has applied the maximum applicable torque and is therefore applying a sufficiently high clamping force.

[0103] The second clamping device 274 clamps the outer jacket 88 of the cable 4 by clamping the compression seal 276 between the end face 282 of the main body 254 and the end face 278 of the compression sleeve 280 located in the outer nut 256. The compression sleeve 280 is slidably mounted in the outer nut 256 against the force of the compression spring 196. An indicator portion in the form of a colored area 198 is provided on the outer surface of the compression sleeve 280, and when sufficient clamping force is applied to the compression seal 276 to cause it to displace radially inwardly to a sufficient degree to apply sufficient clamping force to the outer jacket 88 of the cable 4, the colored area 198 of the compression sleeve 280 protrudes from the end of the outer nut 256, providing a visual indication to the inspector that sufficient clamping force has been applied.

[0104] The second clamping device 274 is further provided with a prevention device in the form of a ratchet member 342 for preventing excessive clamping force from being applied to the compression seal 276. The ratchet member 342 has an internal threaded surface 384 that engages with an external threaded surface 386 on the main body 254, and has a resilient protrusion 344 extending from its outer surface that engages with a groove 346 on the inner surface of the outer nut 256.

[0105] A clamping force is applied to the compression seal 276 by rotation of the outer nut 256 relative to the main body 254. As long as the applied torque is less than a second predetermined level, the protrusions 344 on the ratchet member 342 engage with the grooves 346 on the inner surface of the outer nut 256, causing the ratchet member 342 to rotate with the outer nut 256. This, in turn, causes the threaded surface 384 on the inner surface of the ratchet member 342 to engage with the threaded surface 286 on the outer surface of the main body 254, thereby moving the outer nut 256 axially relative to the main body 254 and clamping the compression seal 276 between the main body 254 and the compression sleeve 280. When the compression seal 276 is fully clamped between the main body 254 and the compression sleeve 280, application of the second predetermined level of torque causes the protrusions 344 on the ratchet member 342 to slide out of the grooves 346 of the outer nut 256, allowing the outer nut 256 to rotate relative to the ratchet member 342 without being able to apply further torque via the second clamping device 274. As the outer nut 256 rotates relative to the main body 254, this indicates to the user that the second clamping device 274 has applied the maximum applicable torque and is therefore applying a sufficiently high clamping force.

[0106] Figure 21 and Figure 22 A fifth embodiment of a cable gland 350 is shown. The cable gland 350 has a first clamping device 358 for clamping the armor layer 60 of the cable 4. The first clamping device 358 has a clamping portion 362 and a clamping ring 364 for surrounding the clamping portion 362 to clamp the armor layer 60 of the cable 4 between the clamping ring 364 and the clamping portion 362. The clamping portion 362 abuts against an abutment surface 366 at the end of the inlet piece 352, and the clamping ring 364 abuts against an end surface 378 of a compression sleeve 380 located within the end of the main body 354. The compression sleeve 380 is slidably mounted within the main body 354 against the force of a compression spring 296. An indicator portion in the form of a colored area 298 is provided on the outer surface of the compression sleeve 380. When sufficient clamping force is applied to the armor layer 60 of the cable 4, the colored area 298 of the compression sleeve 380 protrudes from the end of the main body 354, providing a visual indication to an inspector that sufficient clamping force has been applied.

[0107] The first clamping device 358 is provided with a prevention device in the form of a ratchet member 442 for preventing the first clamping device 358 from applying an excessive clamping force to the armor layer 60. The ratchet member 442 has an internal threaded surface 470 that engages with the external threaded surface 372 of the inlet member 352, and has a resilient protrusion 444 extending from its outer surface, which engages with a groove 446 on the inner surface of the main body 354.

[0108] Rotation of the main body 354 relative to the inlet piece 352 applies a clamping force to the armor 60 of the cable 4. As long as the applied torque is less than a second predetermined level, the protrusions 444 on the ratchet member 442 engage with the grooves 446 on the inner surface of the main body 354, causing the ratchet member 442 to rotate with the main body 354. This, in turn, causes the threaded surface 370 on the inner surface of the ratchet member 442 to engage with the threaded surface 372 on the outer surface of the inlet piece 352, thereby axially moving the main body 354 relative to the inlet piece 352 and clamping the armor 60 between the clamping ring 364 and the clamping portion 362. When the armor 60 is fully clamped between the clamping ring 364 and the clamping portion 362, application of the second predetermined level of torque causes the protrusions 444 on the ratchet member 442 to slide out of the grooves 446 on the main body 354, allowing the main body 354 to rotate relative to the ratchet member 442 and preventing further torque from being applied by the first clamping device 358. When the main body portion 354 is rotated relative to the ratchet member 442, this indicates to the user that the clamping device 358 has applied the maximum applicable torque and is therefore applying a sufficiently high clamping force.

[0109] Figures 23 to 26 A sixth embodiment of a cable gland 450 is shown. Cable gland 450 clamps the outer jacket 88 of the cable 4 by compressing a seal 502 against the cable 4 using resilient fingers 504 disposed on top of a compression spring 190. End surfaces 506 of the compression spring 190, opposite the resilient fingers 504, abut against the end surface of the inlet member 452. Rotation of the main body 454 relative to the inlet member 452 applies a clamping force to the outer jacket 88 of the cable 4. This causes the threaded surfaces 470 on the inner surface of the main body 454 to engage with the threaded surfaces 472 on the outer surface of the inlet member 452, thereby axially moving the main body 454 relative to the inlet member 452 and forcing the resilient fingers 504 to engage with inclined surfaces 508 within the main body 454. This action deflects the resilient fingers 504 inwardly toward the cable 4, pushing the seal 502 into contact with the outer jacket 88 of the cable 4. When more torque is applied to the main body portion 454, the compression spring 190 is compressed until the end surface of the main body portion 454 abuts the abutment 510 on the inlet piece 452, preventing further movement of the main body portion 454 relative to the inlet piece 452. When the main body portion 454 abuts the inlet piece 452, this provides a visual indication to the inspector that a sufficiently high clamping force has been applied, but prevents the application of excessive clamping force.

[0110] Reference Figure 27 and Figure 28 , shows a seventh embodiment of a cable gland 550, wherein Figures 17 to 20 Components common to the illustrated embodiments are denoted by the same reference numerals but incremented by 300. The cable gland 550 has a single clamping device 574 for clamping the outer jacket 88 of the cable 4.

[0111] The clamping device 574 clamps the outer jacket 88 of the cable 4 by clamping the compression seal 576 between the end face 582 of the main body 554 and the end face 578 of the compression sleeve 580 located in the outer nut 556. The compression sleeve 580 is slidably mounted on the outer nut 556 against the force of the compression spring 496. An indicator portion in the form of a colored area 498 is provided on the outer surface of the compression sleeve 580, and when sufficient clamping force is applied to the compression seal 576 to cause it to displace radially inwardly to apply sufficient clamping force to the outer jacket 88 of the cable 4, the colored area 498 of the compression sleeve 580 protrudes from the end of the outer nut 556, providing a visual indication to the inspector that sufficient clamping force has been applied.

[0112] The clamping device 574 is provided with a prevention device in the form of a ratchet member 642 for preventing excessive clamping force from being applied to the compression seal 576. The ratchet member 642 has an internal threaded surface 684 that engages with an external threaded surface 686 on the main body 554, and has a resilient protrusion 644 extending from its outer surface that engages with a groove 646 on the inner surface of the outer nut 556.

[0113] A clamping force is applied to the compression seal 576 by rotation of the outer nut 556 relative to the main body 554. As long as the applied torque is less than a second predetermined level, the protrusions 644 on the ratchet member 642 engage with the grooves 646 on the inner surface of the outer nut 556, causing the ratchet member 642 to rotate with the outer nut 556. This, in turn, causes the threaded surface 684 on the inner surface of the ratchet member 642 to engage with the threaded surface 586 on the outer surface of the main body 554, thereby causing the outer nut 556 to move axially relative to the main body 554, clamping the compression seal 576 between the main body 554 and the compression sleeve 580. When the compression seal 576 is fully clamped between the main body 554 and the compression sleeve 580, application of the second predetermined level of torque causes the protrusions 644 on the ratchet member 642 to slide out of the grooves 646 of the outer nut 556, allowing the outer nut 556 to rotate relative to the ratchet member 642 without being able to apply further torque via the clamping device 574. As the outer nut 556 rotates relative to the main body 554, this indicates to the user that the clamping device 574 has applied the maximum applicable torque and is therefore applying a sufficiently high clamping force.

[0114] Those skilled in the art will appreciate that the above embodiments are for illustration only and are not intended to limit the present invention, and that various changes and modifications may be made without departing from the scope of the present invention as defined in the appended claims.

Claims

1. A cable clamping device for surrounding and clamping at least one cable, comprising: a first body portion pivotally mounted to the second body portion to form a body adapted to engage at least one cable; as well as a clamping device for applying a clamping force to the or each cable by urging the first and second body parts toward each other, Wherein, the clamping device comprises: a first component having a first threaded portion; a second component having a second threaded portion adapted to engage with the first threaded portion to urge the first body portion and the second body portion toward each other; and Indicator means is provided for providing a visual indication that the clamping force exceeds a first predetermined level.

2. The cable clamping device according to claim 1, wherein: The indicating device comprises: At least one first indicator portion, wherein the indicator device provides the visual indication by exposing at least part of the at least one first indicator portion so that it is visible externally of the cable clamping device in use.

3. The cable clamping device according to claim 2, wherein: The indicating device further comprises: A first covering device is provided for covering at least one of the first indicating portions to an extent that depends on the clamping force.

4. The cable clamping device according to claim 3, wherein: The first covering device and the first indicating portion are capable of relative movement, and the cable clamping device further comprises: The first actuating device is configured to cause at least one of the first indicating portions to move relative to at least one of the first covering devices toward a state where the exposure degree of the first indicating portion is maximized.

5. A cable clamping device according to any preceding claim, wherein: The indicator means is adapted to provide a visual indication that the clamping force exceeds a second predetermined level, wherein the second predetermined level is higher than the first predetermined level.

6. The cable clamping device according to any one of the preceding claims, further comprising: Preventing means for preventing the clamping force from exceeding a second predetermined level.

7. The cable clamping device according to claim 6, wherein: The preventing means is adapted to limit movement of the first component relative to the second component.

8. The cable clamping device according to claim 7, wherein: The prevention device comprises: At least one third component is configured to enable movement of the first component relative to the second component and to prevent movement of the first component relative to the second component when the clamping force exceeds the second predetermined level.

9. The cable clamping device according to claim 8, wherein: At least one of the third components is adapted to move the first component relative to the second component by transmitting torque between the first component and the second component in the following manner: At least one protrusion and / or groove on the third component engages with a corresponding groove and / or protrusion on the first component or the second component, Wherein, when the clamping force exceeds the second predetermined level, the protrusions and / or grooves are unable to transmit torque through the corresponding grooves and / or protrusions.

10. The cable clamping device according to any one of claims 7 to 9, wherein: The preventing device is adapted to limit movement of the first component relative to the second component by abutting the first component against the second component.

11. A cable clamping device for surrounding and clamping at least one cable, comprising: a first member pivotally mounted to the second member to form a body adapted to engage at least one cable; as well as clamping means for applying a clamping force to the or each cable by urging the first and second parts towards each other, Wherein, the clamping device comprises: Preventing means for preventing application of said clamping force to said or each said cable in excess of a predetermined level.

12. The cable clamping device according to claim 11, wherein: The preventing means is adapted to limit movement of the first component relative to the second component.

13. The cable clamping device of claim 12, wherein the preventing means comprises: At least one third component is configured to enable movement of the first component relative to the second component and to prevent movement of the first component relative to the second component when the clamping force exceeds the predetermined level.

14. The cable clamping device of claim 13, wherein: At least one of the third components is adapted to move the first component relative to the second component in the following manner: At least one protrusion and / or groove on the third component engages with a corresponding groove and / or protrusion on the first component or the second component, Wherein, when the clamping force exceeds the second predetermined level, the protrusions and / or grooves are unable to transmit torque through the corresponding grooves and / or protrusions.

15. The cable clamping device according to any one of claims 11 to 14, further comprising: Indicator means are provided for providing a visual indication that the clamping force exceeds another predetermined level.

16. The cable clamping device of claim 15, wherein: The indicating device comprises: At least one first indicator portion, wherein the indicator device provides the visual indication by exposing at least part of the at least one first indicator portion so that it is visible externally of the cable clamping device in use.

17. The cable clamping device of claim 16, wherein: The indicating device further comprises: A first covering device is provided for covering at least one of the first indicating portions to an extent that depends on the clamping force.

18. The cable clamping device of claim 17, wherein: The first covering device and the first indicating portion are capable of relative movement, and the cable clamping device further comprises: The first actuating device is configured to cause at least one of the first indicating portions to move relative to at least one of the first covering devices toward a state where the exposure degree of the first indicating portion is maximized.

19. The cable clamping device according to any one of claims 15 to 18, wherein The indicating means is adapted to provide a visual indication that the clamping force exceeds the further predetermined level, wherein the further predetermined level is lower than the predetermined level.

20. A cable gland for clamping a cable passing through the cable gland and comprising: a first housing portion having a first threaded portion; a second housing portion having a second threaded portion adapted to engage the first threaded portion to move the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland; as well as a clamping device adapted to apply a clamping force to the cable, wherein the clamping device comprises at least one resilient member between the first shell portion and the second shell portion, such that movement of the second shell portion relative to the first shell portion compresses at least one of the resilient members in a direction substantially parallel to the longitudinal axis of the cable gland, thereby causing the cable gland to provide a visual indication that the clamping force exceeds a first predetermined level.

21. The cable gland of claim 20, further comprising: At least one first indicator portion, wherein the cable gland provides the visual indication by exposing at least part of the at least one first indicator portion by compression of at least one resilient member such that the part is visible externally of the cable gland in use.

22. The cable gland of claim 21, wherein The visual indication is provided by causing at least a portion of at least one of the first indicators to protrude from the first housing portion or the second housing portion.

23. The cable gland according to any one of claims 20 to 22, wherein The cable gland is adapted to provide a visual indication that the clamping force exceeds a second predetermined level, wherein the second predetermined level is higher than the first predetermined level.

24. The cable gland according to any one of claims 20 to 23, wherein The cable gland provides the visual indication by abutting the first housing portion against the second housing portion.

25. The cable gland according to any one of claims 20 to 24, wherein At least one of the resilient members includes a corresponding seal for engaging a surface of a cable, wherein compression of the seal causes the seal to sealingly engage the cable surface.

26. The cable gland according to any one of claims 20 to 25, wherein At least one of the resilient members comprises a respective compression spring.

27. The cable gland according to any one of claims 20 to 26, wherein The cable gland is adapted to clamp the armor layer of a cable passing through the cable gland.

28. The cable gland according to any one of claims 20 to 27, further comprising: Preventing means for preventing the clamping force from exceeding a second predetermined level.

29. The cable gland of claim 28, wherein The preventing means is adapted to limit movement of the first housing part relative to the second housing part.

30. The cable gland of claim 29, wherein The prevention device comprises: At least one third housing portion is configured to enable movement of the first housing portion relative to the second housing portion and to prevent movement of the first housing portion relative to the second housing portion when the clamping force exceeds the second predetermined level.

31. The cable gland of claim 30, wherein At least one of the third housing parts is adapted to move the first housing part relative to the second housing part in the following manner: At least one protrusion and / or groove on the third housing part engages with a corresponding groove and / or protrusion on the first housing part or the second housing part, Wherein, when the clamping force exceeds the second predetermined level, the protrusions and / or grooves are unable to transmit torque through the corresponding grooves and / or protrusions.

32. A cable gland according to any one of claims 29 to 31, wherein The preventing device is adapted to restrict movement of the first housing part relative to the second housing part by abutting the first housing part with the second housing part.

33. A cable gland for clamping a cable passing through the cable gland and comprising: a first housing portion having a first threaded portion; a second housing portion having a second threaded portion adapted to engage the first threaded portion to move the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland; a clamping device adapted to apply a clamping force to the cable as a result of movement of the second housing portion relative to the first housing portion; as well as a preventing device for preventing the clamping force from exceeding a predetermined level and comprising at least one resilient member between the first shell part or the second shell part and the clamping device, so that movement of the second shell part relative to the first shell part causes at least one of the resilient members to be compressed in a direction substantially parallel to the longitudinal axis of the cable gland, and before the clamping force exceeds the predetermined level, the first shell part abuts the second shell part to prevent further movement of the second shell part relative to the first shell part.

34. The cable gland of claim 33, wherein The clamping device is adapted to apply a clamping force to the armour layer of the cable.

35. The cable gland of claim 34, wherein The clamping device includes a first clamping portion and a second clamping portion, wherein the second clamping portion is adapted to surround at least a portion of the first clamping portion to apply a clamping force to the armor layer of the cable due to movement of the second shell portion relative to the first shell portion in a direction substantially parallel to the longitudinal axis of the cable gland.

36. The cable gland of claim 35, wherein The first clamping portion is adapted to engage the first housing portion or at least one of the resilient members, and the second clamping portion is adapted to engage the second housing portion or at least one of the resilient members.

37. The cable gland according to any one of claims 33 to 36, further comprising: At least one seal is configured to engage an outer surface of the cable as a result of movement of the second housing portion relative to the first housing portion in a direction generally parallel to a longitudinal axis of the cable gland.

38. The cable gland of claim 37, further comprising: At least one actuator portion is configured to urge at least one seal into engagement with the outer surface of the cable by sliding engagement with at least one surface of the second body portion that is inclined relative to the longitudinal axis of the cable.

39. A cable gland according to any one of claims 33 to 38, wherein The cable gland is adapted to provide a visual indication that sufficient clamping force has been applied to the cable.

40. The cable gland of claim 39, wherein The visual indication is provided by abutment of the first housing portion and the second housing portion.

41. The cable gland of claim 39 or 40, further comprising: At least one first indicator portion, wherein the cable gland provides the visual indication by exposing at least part of the at least one first indicator portion by compression of at least one resilient member such that the part is visible externally of the cable gland in use.

42. The cable gland of claim 41, wherein The visual indication is provided by causing at least a portion of at least one of the first indicators to protrude from the first housing portion or the second housing portion.

Images