GB2405900A

GB2405900A - Cable clamps

Info

Publication number: GB2405900A
Application number: GB0321187A
Authority: GB
Inventors: Christopher John Calvert
Original assignee: Ellis Patents Ltd
Current assignee: Ellis Patents Ltd
Priority date: 2003-09-10
Filing date: 2003-09-10
Publication date: 2005-03-16
Anticipated expiration: 2023-09-10
Also published as: GB0321187D0; GB2405900B

Abstract

A cable clamp for securing one or more cables or the like,the cable clamp comprising a plurality of members (1,2) coupled so as to define a substantially triangular configuration. At least one of the couplings (3,4) between the members (1,2) is releasable to allow insertion or removal of the cable or cables to or from within the substantially triangular configuration, and one of the members (1) releasably coupled at a first end region (3) is pivotally connected by means of a hinge (7) at a second end region (5) to an end region (6) of another member (2). The hinge is formed by an aperture (12) in the end region (6) of one of the members (2), and the hinge end region (5) of the other member (1) which extends through the aperture (12) . One of the members may comprise an extrusion of aluminium.

Description

CABLE CLAMPS

The present invention relates to cable clamps for holding objects such as cables or pipes, in particular to cable clamps (cleats) for holding one or more electrical cables.

Cable clamps are designed to fix and retain cables mounted within them, even in the event of a short-circuit in one of the cables. If adjacent cables are mounted within a clamp and a short circuit occurs, the cables can experience powerful opposing forces caused by the induced magnetic fields. A clamp should be capable of withstanding these forces so as to prevent the cables from breaking free and destroying the clamp.

It is known to provide cable clamps having a substantially polygonal configuration comprising coupled rigid members.

Usually, the clamps are of a substantially triangular configuration, comprising three coupled rigid members, although this is not always so. The clamps are provided with at least one releasable coupling, by means of which two of the rigid members can be uncoupled from each other and separated so as to allow the insertion or removal of the cable or cables to or from within the body of the clamp.

The releasable coupling may be provided by means of a nut and bolt or other such screw-threaded arrangement, the bolt passing through opposing holes in the ends of two of the rigid members and being secured by means of the nut. Both GB-A 2256672 and GB-A-2284444 disclose such a coupling. In GB-A 2284444, each apex of the clamp is coupled by means of such an arrangement, whilst a bolt and rows of opposing teeth are disclosed in GBA-2256672, and end portions of the rigid members are shaped so as to provide a relative sliding engagement at the connections between the members and bolts to secure the connections in GB-A-2255799.

According to one aspect of the present invention there is provided a cable clamp for holding one or more cables or the like, comprising a plurality of members coupled so as to define a substantially polygonal configuration, wherein a first of said members is releasably coupled at a first end - region to allow insertion or removal of said cable or cables to or from within said substantially polygonal configuration, and said first member is coupled by means of a hinge at a second end region thereof to an end region of a second of said members, such that the first member can be displaced pivotally about its second end region, and wherein said hinge is provided by an aperture in the plane of one of the said first and second members, and an end region of the other said member which extends through said aperture.

Preferably said end region of said other member is narrower than each of said first and said second members.

Said end region of said other member may comprise one or more lateral projections, and the hinge aperture may have a first portion through which said lateral projection or projections of said end region of said other member can pass on assembly of the cable clamp, and a second portion through which said lateral projection or projections cannot pass on assembly of the cable clamp. Accordingly said end region of said other member may extend through said second portion of said hinge aperture in the assembled clamp, and inwardly projecting elements may be formed in said hinge aperture to prevent said end region from being displaced into said first portion of said hinge aperture.

In a preferred embodiment, said end region of said other member and said hinge aperture are each substantially T- shaped, whilst the pivotal displacement of said first member may be generally in the plane of said substantially polygonal configuration.

At least one of the plurality of members may be or may comprise an extrusion of aluminium or aluminium alloy.

In a preferred embodiment of cable clamp, there are two said members, the two said members being said first member and said second member, and wherein said first member defines one side of the said substantially polygonal, preferably triangular, configuration and said second member defines the remaining sides of the polygonal configuration.

In the triangular case, said second member which defines two sides of the substantially triangular configuration may define a securable base side and one of the other two sides and may comprise an extrusion of aluminium or aluminium alloy.

Preferably said second member defining two sides has a curved apex at one end of its securable base side, and two free ends one of which opposes said securable base side to form part of a said releasable coupling with said first member, and another free end coupled to the said first member by means of said hinge.

One or more of said plurality of members may have an inwardly facing supporting surface shaped to accommodate said one or more cables or the like, preferably having concave portions.

In a cable clamp according to the invention, the or each of said releasable couplings may include a bolt, studding or other screw-threaded member, whilst one of said plurality of members may have an aperture to receive a securing member to attach the clamp to a support.

A cable clamp according to the first aspect of the invention allows a first member of the clamp to be displaced pivotally by means of a hinged joint with a second member of the clamp.

Advantageously, no other parts need be necessary to form the hinge, for example a separate pivot pin or bolt, making the clamp simple to produce, assemble and maintain.

In a preferred embodiment both or all said members are or comprise extrusions of aluminium or aluminium alloy, whilst the or each member which is or comprises an extrusion of aluminium or aluminium alloy may be formed along its length with one or more reinforcing ribs.

Preferably, each of the members is a rigid member.

According to a second aspect of the present invention there is provided a cable clamp for holding one or more cables or the like, comprising a plurality of members coupled so as to define a substantially polygonal configuration, wherein one or more couplings between members are releasable to allow insertion or removal of said cable or cables to or from within said substantially polygonal configuration, and wherein at; least one of the members is or comprises an extrusion of aluminium or aluminium alloy.

It is known to produce clamps using steel and aluminium and their respective alloys. Aluminium and its alloys are particularly favoured in the industry as they provide strong, low density, clamps which are suitable for many environments.

However, prior art aluminium clamps are made by the slow batch process of sand casting.

A cable clamp according to the second aspect of the invention advantageously may provide a cable clamp comprised of rigid members, wherein at least one of those rigid members is or comprises an extrusion of aluminium or aluminium alloy. Hence the rigid members of the above clamp can be simply and quickly produced.

It is particularly preferable to provide a cable clamp hinged according to the first aspect of the invention, and comprising extrusions of aluminium alloy according to the second aspect of the invention. Such a clamp is easy to produce, put together and maintain.

Reference will now be made, by way of example only, to the accompanying drawings, in which: Figure l - is a side view of part of a clamp according to an embodiment of the invention; Figure 2 - is a side view of the clamp parts of Figure l, with one of the members of the clamp pivotally displaced into the open position; Figure 3 - is an end view of a first member (arm) of the clamp parts of Figures l and 2; Figure 4 - is a view from above of a second member of the clamp parts of Figures l and 2; and Figure 5 - is a perspective view of the clamp parts of Figs l and 2 when incorporated into a complete clamp, provided with a nut and bolt as a releasable coupling at one apex, and with a support member securely attached to its base portion; Figure l shows a side view of a cable clamp or cleat according to an embodiment of the invention. According to this embodiment, the clamp is of a substantially triangular configuration and comprises two, preferably rigid, members l,2. A first member l defines one side of the substantially triangular configuration, and a second member 2 defines the other two sides of the substantially triangular configuration.

A first end region 3 of the first member l can be releasably coupled to a first end region 4 of the second member 2, so as to allow insertion or removal of a cable or cables to or from within the substantially triangular configuration. Such a releasable coupling may be provided by means of, for example, a bolt, studding or other screw-threaded member, together with a nut.

A second end region 5 of the first member l and a second end region 6 of the second member 2 are coupled together to form a hinge 7, such that the first member l can be displaced pivotally about its second end region 5 on the second member 2. This displacement is generally in the plane of the substantially triangular configuration. The clamp as shown in Figure l is in the closed position, although the releasable coupling at the top apex is not depicted.

Figure 2 shows the clamp in the open position, the first member l having been displaced outwardly in the triangular plane of the clamp, the displacement being pivotal about the second end region 6 of the second member 2. In the open position, a cable or cables or the like can be inserted into or removed from the interior of the clamp.

Figure 3 shows an end view of the first member l alone. As can be seen, the first member l comprises a main body 8 having the first and second end regions 3 and 5 respectively. In this embodiment, the first end region 3 is provided with a circular hole, through which a bolt or stud can pass so as to connect the first member l releasably to another (in this case the second) member 2. The second end region 5 of the first member l is narrower in width than the main body 8 of the first member l, and extends from the main body 8 substantially longitudinally in the plane of the main body 8 as can be seen in Figs. l and 2. The second end region 5 has two laterally projecting portions or lateral projections 9, projecting outwardly on both sides perpendicular to the longitudinal axis of the first member l and away from a narrow neck portion 5a of the end region 5, as shown in Figure 3. Thus, the second end region 5 as depicted in Figure 3 is substantially T- shaped. Alternatively, the second end region 5 could be designed to have a different shape with a narrow section and a wider section or lateral projections.

Figure 4 shows the base of the second member 2 alone of the clamp, viewed from above. In this embodiment, the second member 2 defines two sides of the substantially triangular configuration, comprising securable base side ll and one of the other two sides. Referring back to Figures l and 2, the second member 2 has an apex lo at one end of its securable base side ll and first 4 and second 6 free ends.

As already described, the first free end 4 of the member 2 forms part of a releasable coupling to the first end region 3 of the first member l, and as such has a similar construction for accepting a nut and bolt. The second free end 6 of the second member 2, as also mentioned hereinbefore, is coupled by t means of the hinge 7 to the second end region 5 of the first member 1.

As can be seen in Figure 4, at the second end region 6 of the second member 2 there is shown an aperture 12 which forms part of the hinge 7. This aperture 12 lies in the curved plane of the securable base side 11 of the second member 2. The aperture 12 has two portions, a first portion 13 and a second portion 14, wherein the first portion 13 has a greater width than the second portion 14. As can be seen, in this instance the aperture 12 is accordingly substantially T-shaped.

Alternatively, the aperture 12 could be provided with a different shape, for example two conjoined circles, one having a larger diameter than the other.

The hinge 7 between the first and second members 1,2 is provided by the respective second end regions 5,6 of the members. The second end region 5 of the first member 1 (the hinge end region) extends through the aperture 12 (hinge aperture) of the second member 2 such that the lateral projections 9 (wider section) of the hinge end region 5 lie below the plane of the aperture 12 with the end region 5 extending through the aperture 12 and the remaining major part of the first member 1 being above the aperture plane. In particular, the two portions 13, 14 of the aperture 12 are dimensioned such that the lateral projections 9 of the hinge end region 5 can pass through the first (wider) aperture portion 13, but cannot pass through the second (narrower) aperture portion 14 during assembly of the hinge 7. It is therefore important that the shape of the hinge aperture 12 and the shape of the hinge end region 5 match in this respect.

Hence, the hinge end region 5 (including projections) can be passed through the first portion 13 of the hinge aperture 12 it' during assembly of the clamp, and then displaced transversely, such that the neck 5a of the hinge end region 5 passes into the second, narrower, portion 14 of the hinge aperture 12, with the lateral projections 9 underneath the aperture portion 14. Since the lateral projections 9 of the end region 5 are wider than the second aperture portion 14, the end region 5 cannot be withdrawn through the second portion 14 of the aperture 12.

In order to secure the hinge 7, and thus prevent the first and second members 1, 2 from becoming detached from one another at their respective second end regions 5, 6, the hinge end region must be prevented from being displaced transversely into the wider first portion 13 of the hinge aperture 12 from the narrower second aperture portion 14. Preferably, inwardly projecting elements (not shown) are provided in the hinge aperture 12 so as to prevent the neck 5a of the hinge end region 5 from moving into the wider first portion 13 of the aperture 12. These inwardly projecting elements can be formed; by pinching or nipping inwardly the edges of the second portion 14 of the aperture 12, at the opposed corners between the two aperture portions 13, 14, after assembly of the clamp with the neck 5a of the first member end region 5 having been displaced into the hinge narrower aperture portion 14. ] Preferably the inwardly projecting elements are slight projections jutting out into the aperture 12, in the plane of the aperture 12 and so, in order to be effective, it is desirable that the width of the narrow second portion 14 of the aperture 12 is only slightly greater than the width of the neck 5a of the end region 5 of the hinge 7 above its wider section or lateral projections 9. This causes the edges of the hinge end region neck 5a to abut against the inwardly projecting elements when the hinge end region 5 is displaced ) transversely, thus preventing the hinge end region 5 from being displaced into the wider first portion 13 of the hinge aperture 12 such that the hinge 7 can be disassembled with the clamp members 1 and 2 becoming separated at the hinge 7.

The inwardly projecting elements can be formed, for example, by cutting small grooves in the upper (or lower) face of the end region 6 of the second member 2 close to and substantially parallel to the opposed sides of the second portion 14 of the aperture 12 and extending away from the first portion 13 of the aperture 12. The resulting thin strips of material produced between the grooves and the narrow aperture portion 14 can then be forced to bend inwardly into the narrow aperture portion 14, thus narrowing the aperture 12 at the corners between the first and second aperture portions 13, 14 and trapping the neck 5a of the first member end region 5 in the narrow aperture portion 14.

In this manner the hinge 7 between the first and second members 1, 2 can be formed, about which the first member 1 can be pivotally displaced with respect to the second member 2, as shown in Figure 2. The hinge 7 has no parts or components other than the first and second members 1 and 2 themselves, thus rendering the hinge 7 easy to manufacture and simple to maintain.

In pivoting, the neck 5a is retained in the narrow aperture portion 14, and the end region 5 including neck 5a, and the aperture portion 14, should be so dimensioned relative to one another that pivoting can occur freely and in a sufficiently wide range. Pivoting, and the range of pivoting is assisted by the plane of the end region 6 of the second member 2 being curved as shown, in such manner as to present a convex face to the upper major part of the first member 1.

Also shown in Figure 4 is an aperture 15 in the centre of the base side of the second member 2. The aperture 15 is formed in a depressed portion 15a at a central region of the base portion, this depressed portion 15a also being visible in Figures 1 and 2. In the complete clamp the bottom of the second member 2 is securely attached to a support member 16, as shown in Figure 5 but omitted from Figures 1, 2 and 4 for the sake of clarity.

Finally, Figure 5 shows a perspective view of the complete clamp having a nut and bolt arrangement as a releasable coupling at the top of the clamp, and a support member 16 attached by welding for example, to the base side of the member 2 and showing an attachment bolt, for the complete clamp as a whole, extending through the aperture 15 and the support member 16. A nut and bolt arrangement for the releasable coupling between members 1 and 2 allows a degree of adjustment of the clamp, so that cables within the clamp can be tightly held. The support member 16 and the associated attachment bolt enable the clamp to be fastened to a cable support ladder or other such structure, while the aperture 15 and depressed portion 15a in the base of the clamp above the support member 16, can be formed by stamping the metal strip providing the second member 2. The depressed portion 15a provides space for the head of the attachment bolt. The bolt passes through the aperture 15 as well as through a hole in the support member 16, thus the bolt provides an additional means of securing second member 2 to the support member 16.

In fact, the first and second members 1, 2 are metal strips of equal width, and are formed with three reinforcing ribs (a broad central rib and narrow ribs at the edges) along their length, as shown in Figures 3, 4 and 5, particularly to the right of Figure 4. This helps to strengthen the members of the clamp. The sides of the clamp are shaped so as to accommodate one or more cables, in the case of the clamp I illustrated to accommodate three cables in trefoil arrangement.

Thus, two cables can rest along the base of the clamp, with a third cable positioned centrally above the first two, cable supporting surfaces 17 of the clamp being provided with concave portions to match the outer surface contours of the three cable bundles.

Preferably, at least the second member 2 of the clamp (the member defining two sides of the substantially triangular configuration) is or comprises an extrusion of aluminium or aluminium alloy. Aluminium or aluminium alloy provides a suitable material for cable clamps because of its relatively high strength and low density. However, clamps comprised of aluminium have previously been made by the slow process of sand casting. By extruding narrow strips of aluminium or aluminium alloy, and then pressing and/or stamping the strips to form the members 1 and 2 of the clamp, a clamp can be more quickly and easily manufactured. This is particularly advantageous for clamps having a hinge as described herein, whereby the extruded members can be conveniently and quickly joined by means of the pivoting hinge 7 without the need to provide any extra members or components.

Although the clamp described and illustrated herein has a substantially triangular configuration and comprises two, preferably rigid, members, embodiments of the invention are not limited to this particular construction. The clamp could be of any generally polygonal shape and could comprise more than two members. The supporting surfaces of the clamp could be shaped to accommodate a single cable or, depending on the particular polygonal construction, to accommodate more than three cables.

Claims

CLAIMS: 1. A cable clamp for holding one or more cables or the I like,

comprising a plurality of members coupled so as to define a substantially polygonal configuration, wherein a first of said members is releasably coupled at a first end region to allow insertion or removal of said cable or cables to or from within said substantially polygonal configuration, and said first member is coupled by means of a hinge at a second end region thereof to an end region of a second of said members, such that the first member can be displaced pivotally about its second end region, and wherein said hinge is provided by an aperture in the plane of one of the said first and second members, and an end region of the other said member which extends through said aperture.
2. A cable clamp according to claim 1, wherein said end region of said other member is narrower than each of said first and said second members.
3. A cable clamp according to claim 1 or 2, wherein said end region of said other member has one or more lateral projections.
4. A cable clamp according to claim 3, wherein said hinge aperture has a first portion through which said lateral projection or projections of said end region of said other member can pass on assembly of the cable clamp, and a second portion through which said lateral projection or projections cannot pass on assembly of the cable clamp.
5. A cable clamp according to claim 4, wherein said end region of said other member extends through said second portion of said hinge aperture in the assembled clamp, and wherein inwardly projecting elements are formed in said hinge aperture to prevent said end region from being displaced into said first portion of said hinge aperture.
6.A cable clamp according to claim 3, 4 or 5, wherein said end region of said other member and said hinge aperture are each substantially T-shaped.
7.A cable clamp according to any preceding claim, wherein the displacement of said first member is generally in the plane of said substantially polygonal configuration.
8. A cable clamp according to any preceding claim, wherein at least one of the plurality of members is or comprises an extrusion of aluminium or aluminium alloy.
9. A cable clamp according to any preceding claim, wherein there are two said members, the two said members being said first member and said second member.
10. A cable clamp according to claim 9, wherein said first member defines one side of the said substantially polygonal configuration and said second member defines the remaining sides of the said substantially polygonal configuration.
11. A cable clamp according to any preceding claim, wherein the substantially polygonal configuration is a substantially triangular configuration.
12. A cable clamp according to claim 11 when appended to claim 10, wherein said second member which defines two sides of the substantially triangular configuration defines a securable base side and one of the other two sides and is or comprises an extrusion of aluminium or aluminium alloy.
13. A cable clamp according to claim 12, wherein said second member defining two sides has a curved apex at one end of its securable base side, and two free ends one of which opposes said securable base side to form part of a said releasable coupling with said first member, and another free end coupled to the said first member by means of said hinge.
14. A cable clamp according to any preceding claim, wherein i one or more of said plurality of members has an inwardly facing supporting surface shaped to accommodate said one or more cables or the like.
15. A cable clamp according to claim 14, wherein said supporting surface of said one or more members has concave portions to accommodate said one or more cables or the like.
16. A cable clamp according to any preceding claim, wherein the or each of said releasable couplings includes a bolt, studding or other screwthreaded member.
17. A cable clamp according to any preceding claim, wherein one of said plurality of members has an aperture to receive a securing member to attach the clamp to a i support.
18. A cable clamp according to claim 8, or any of claims 9 to 17 when appended to claim 8, wherein the or each member which is or comprises an extrusion of aluminium or aluminium alloy is formed along its length with one or more reinforcing ribs.
19. A cable clamp according to any preceding claim, wherein each of the members is a rigid member.
20. A cable clamp according to any preceding claim, wherein the plane of the member in which is provided the hinge aperture is curved at the location of the hinge aperture, in such manner as to present a convex face to I a major part of the first member.
21. A cable clamp for holding one or more cables or the like, comprising a plurality of members coupled so as to define a substantially polygonal configuration, wherein one or more couplings between members are releasable to allow insertion or removal of said cable or cables to or from within said substantially polygonal configuration, and wherein at least one of the members is or comprises an extrusion of aluminium or aluminium alloy.
22. A cable clamp substantially as hereinbefore described with reference to the accompanying drawings.