Slim swivelling joint

Abstract

A swivelling joint is provided, comprising a first member associated with a first leg, a second member associated with a second leg, and a third member. The first member has a first bearing member that is circular, and oriented at an acute angle to the first leg's longitudinal direction. The second member has a second bearing member that is square. The first bearing member is located generally between the second bearing member and the third member. The joint includes connecting bolts and a second pair of connecting bolts passing through aligned apertures in the second bearing member and the third member, positioned outside the diameter of the first bearing member. The second member includes two channels. A nominal cylinder extending along the axis of two bolts, and having a diameter equal to the maximum transverse dimension of the respective bolt head, extends within one of the respective channels.

Description

“SLIM SWIVELLING JOINT”Field of the Invention

[0001] The present invention relates to a swivelling joint for use in light poles and similar structures. The swivelling joint is expected to be used in light poles in excess of 2m in height, or light poles having a light located outside of easy reach. It is anticipated that the swivelling joint may be used in other poles such as flag poles, or in raised elongate structures such as mountings for securing cameras.Background to the Invention

[0002] The Swivelpole™ is described in the International Patent Application published as WO0125687, the contents of which are incorporated herein by reference. This product consists of a light pole having a swivelling joint along its length. The swivelling joint allows for safer and easier changing and repair of lights than had previously been available.

[0003] In recent years the original Swivelpole™ has been largely superseded by a swivelling joint sold under the trade mark Maxis™. The Maxis™ joint shows all of the advantages of the original Swivelpole™, but is both significantly easier to manufacture and less prone to water ingress.

[0004] The Maxis™ joint has proved highly successful. Nonetheless, there are some situations in which the Maxis™ joint is unsuitable. The Maxis™ joint requires a particular geometry to achieve its purpose, with a generally square covering member extending laterally away from a central cylindrical pole portion. This means that the Maxis™ joint may not be suitable in situations where there is insufficient lateral space around the pole within which it is incorporated.

[0005] The present invention seeks to propose a slim swivelling joint which maintains the advantages of the Maxis™ joint while enabling use in situations where space is relatively limited.Summary of the Invention

[0006] According to one aspect of the present invention there is provided a swivelling joint including a first member, a second member, and a third member; the first member being associated with a first leg, the first leg having a longitudinal direction, the first member having a first bearing member that is oriented at an acute angle relative to the longitudinal direction of the first leg, the first bearing member including an opening in communication with the first leg; the second member being associated with a second leg, the second leg having a longitudinal direction, the second member having a second bearing member that is oriented at an acute angle relative to the longitudinal direction of the second leg, the second bearing member including an opening in communication with the second leg; the first bearing member having a generally circular outer perimeter, the outer perimeter having a diameter; the second bearing member having a generally square outer perimeter, the square outer perimeter having a side dimension greater than the diameter of the first bearing member; the third member having a generally square outer perimeter; the first bearing member being located generally between the second bearing member and the third member; the swivelling joint including a first pair and a second pair of connecting bolts; each bolt being arranged to pass through aligned apertures in the second bearing member and the third member, the bolts being arranged to locate outside the diameter of the first bearing member; wherein each of the first pair of connecting bolts has an axis about which it rotates, the axis of each of the first pair of connecting bolts passing outside the second leg; and each of the second pair of connecting bolts has an axis about which it rotates, each of the second pair of connecting bolts having a head with a maximum transverse dimension; and wherein the second member includes two channels, such that a nominal cylinder extending along an axis of one of the second pair ofconnecting bolts and having a diameter equal to the maximum transverse dimension of the respective connecting bolt head extends within a respective channel.

[0007] Advantageously, this allows the use of larger connecting bolts while reducing the required size of the second and third bearing members.Additionally, it allows for a larger diameter of the second leg when compared to the side dimension of the second bearing member.

[0008] According to another aspect of the present invention there is provided a swivelling joint including a first member, a second member, and a third member; the first member being associated with a first leg, the first leg having a longitudinal direction, the first member having a first bearing member that is oriented at an acute angle relative to the longitudinal direction of the first leg, the first bearing member including an opening in communication with the first leg; the second member being associated with a second leg, the second leg having a longitudinal direction, the second member having a second bearing member that is oriented at an acute angle relative to the longitudinal direction of the second leg, the second bearing member including an opening in communication with the second leg; the second leg having an internal cylindrical portion arranged to receive a cylindrical light pole portion, the internal cylindrical portion having an internal diameter Di; the first bearing member having a generally circular outer perimeter, the outer perimeter having a diameter D2; the second bearing member having a generally square outer perimeter, the square outer perimeter having a side dimension L; the third member having a generally square outer perimeter; the first bearing member being located generally between the second bearing member and the third member; the swivelling joint including a first pair and a second pair of connecting bolts; each bolt being arranged to pass through alignedapertures in the second bearing member and the third member, the bolts being arranged to locate outside the diameter of the first bearing member; wherein each of the first pair of connecting bolts has an axis about which it rotates, the axis of each of the first pair of connecting bolts passing outside the second leg; and each of the second pair of connecting bolts has an axis about which it rotates, each of the second pair of connecting bolts having a head with a maximum transverse dimension; and wherein the second member includes two channels, such that a nominal cylinder extending along an axis of one of the second pair of connecting bolts and having a diameter equal to or greater than the maximum transverse dimension of the respective connecting bolt head extends within a respective channel; wherein L > D2; and the ratio of L: Di is between 2.2:1 and 2.6:1.

[0009] This ratio compares with a ratio of about 2.75:1 for the Maxis™ joint. Importantly, the relatively increased size of Di allows for a vibration dampening sleeve to be located within the internal cylindrical portion.

[0010] It is preferred that the internal cylindrical portion has an upper lip having a diameter D3, wherein D3 is less than Di. This provides a restraining ridge against which a vibration dampening sleeve can be retained. It is preferred that the swivelling joint includes a vibration dampening sleeve located within the internal cylindrical portion.

[0011] It is preferred that the internal cylindrical portion of the leg abuts a lower internal cylindrical portion of the second member, the lower internal cylindrical portion of the second member having a diameter less than or equal to the diameter D3 of the upper lip. This provides both a lower restraining ridge for a vibration dampening sleeve, and also allows for a reduction in an external diameter of the second member in the vicinity of the channels.

[0012] It is preferred that the ratio of L:Ds is between 2.4:1 and 2.6:1. This permits a suitably sized vibration dampening sleeve to be restrained in the internal cylindrical portion while also allowing for a relatively large diameter light pole portion to be inserted within.

[0013] It is preferred that the vibration dampening sleeve has an outer diameter of Di and an inner diameter less than Ds and less than the diameter of the lower internal cylindrical portion of the second member. In this way a light pole portion inserted within the vibration dampening sleeve may be prevented from contact with the second member 50.

[0014] A pole securing bolt may extend radially through the lower internal cylindrical portion of the second member. The pole securing bolt may be used to prevent axial movement of a light pole portion. The light pole portion preferably has an aperture arranged to receive the pole securing bolt, with the aperture being larger than the pole securing bolt such that an annular air gap exists between the pole securing bolt and the light pole portion.

[0015] According to a third aspect of the present invention there is provided a swivelling joint including a first member, a second member, and a third member; the first member being associated with a first leg, the first leg having a longitudinal direction, the first member having a first bearing member that is oriented at an acute angle relative to the longitudinal direction of the first leg, the first bearing member including an opening in communication with the first leg; the second member being associated with a second leg, the second leg having a longitudinal direction, the second member having a second bearing member that is oriented at an acute angle relative to the longitudinal direction of the second leg, the second bearing member including an opening in communication with the second leg; the second leg having an internal cylindrical portion arranged to receive a cylindrical light pole portion, the internal cylindrical portion having an internal diameter Di;the first bearing member having a generally circular outer perimeter, the outer perimeter having a diameter D2; the second bearing member having a generally square outer perimeter; the third member having a generally square outer perimeter; the first bearing member being located generally between the second bearing member and the third member; the swivelling joint including a first pair and a second pair of connecting bolts; each bolt being arranged to pass through aligned apertures in the second bearing member and the third member, the bolts being arranged to locate outside the diameter of the first bearing member; wherein each of the first pair of connecting bolts has an axis about which it rotates, the axis of each of the first pair of connecting bolts passing outside the second leg; and each of the second pair of connecting bolts has an axis about which it rotates, each of the second pair of connecting bolts having a head with a maximum transverse dimension; the second member including two channels, such that a nominal cylinder extending along an axis of one of the second pair of connecting bolts and having a diameter equal or greater to the maximum transverse dimension of the respective connecting bolt head extends within a respective channel; wherein the internal cylindrical portion has an upper lip having a diameter less than Di. This provides a restraining ridge against which a vibration dampening sleeve can be retained.

[0016] It is preferred that the internal cylindrical portion abuts a lower internal cylindrical portion of the second member, the lower internal cylindrical portion of the second member having a diameter less than or equal to the diameter of the upper lip. This provides both a lower restraining ridge for a vibration dampening sleeve, and also allows for a reduction in external diameter of the second member in the vicinity of the channels.

[0017] According to a fourth aspect of the present invention there is provided a swivelling joint including a first member, a second member, and a third member; the first member being associated with a first leg, the first leg having a longitudinal direction, the first member having a first bearing member that is oriented at an acute angle relative to the longitudinal direction of the first leg, the first bearing member including an opening in communication with the first leg; the second member being associated with a second leg, the second leg having a longitudinal direction, the second member having a second bearing member that is oriented at an acute angle relative to the longitudinal direction of the second leg, the second bearing member including an opening in communication with the second leg; the second leg having an internal cylindrical portion arranged to receive a cylindrical light pole portion, the internal cylindrical portion having an internal diameter Di;the first bearing member having a generally circular outer perimeter, the outer perimeter having a diameter D2; the second bearing member having a generally square outer perimeter; the third member having a generally square outer perimeter; the first bearing member being located generally between the second bearing member and the third member; the swivelling joint including a first pair and a second pair of connecting bolts; each bolt being arranged to pass through aligned apertures in the second bearing member and the third member, the bolts being arranged to locate outside the diameter of the first bearing member; wherein each of the first pair of connecting bolts has an axis about which it rotates, the axis of each of the first pair of connecting bolts passing outside the second leg; and each of the second pair of connecting bolts has an axis about which it rotates, each of the second pair of connecting bolts having a head with a maximum transverse dimension;the second member including two channels, such that a nominal cylinder extending along an axis of one of the second pair of connecting bolts and having a diameter equal or greater to the maximum transverse dimension of the respective connecting bolt head extends within a respective channel; wherein the second leg includes a vibration dampening sleeve located within the internal cylindrical portion.

[0018] The internal cylindrical portion may have an upper lip having an inner diameter less than Di.

[0019] It is preferred that the vibration dampening sleeve has an inner diameter less than that of the upper lip. In this way, a light pole portion received within the vibration dampening sleeve may not touch the upper lip. The vibration dampening sleeve acts to prevent the transmission of vibration between the light pole portion and the second member.

[0020] The second member may include a flared connection portion connecting the second bearing member to the second leg. The channels may extend within outer walls of the flared connection portion. The lower internal cylindrical portion of the second member may be at least partially located within the flared connection portion.

[0021] In a preferred embodiment the first bearing member includes a plurality of recesses spaced around its outer perimeter. The second bearing member includes at least one aperture arranged to align, in use, with a selected one of the plurality of recesses. The swivelling joint includes a pin arranged to extend through the at least one aperture and the selected one of the plurality of recesses to prevent relative rotation of the first and second bearing members.

[0022] It is preferred that the third member includes at least one recess arranged to align with the at least one aperture of the first bearing member.

[0023] It is preferred that the vibration dampening sleeve is made of rubber.

[0024] It is preferred that the swivelling joint includes an earth-wire receiving portion mounted to the second member. In this way a pole portion received within the second member can be electrically connected to the second member even if there is no other metal to metal contact, such as when all other contact is through a vibration dampening sleeve.Brief Description of the Drawings

[0025] It will be convenient to further describe the invention with reference to preferred embodiments of the present invention. Other embodiments are possible, and consequently the particularity of the following discussion is not to be understood as superseding the generality of the preceding description of the invention. In the drawings:

[0026] Figure 1 is a perspective of a swivelling joint in accordance with the present invention, following attachment of a light pole portion to a second member of the swivelling joint;

[0027] Figure 2 is an exploded view of the swivelling joint of Figure 1 without an attached light pole portion;

[0028] Figure 3 is a lower perspective of the swivelling joint of Figure 1 , shown with an attached light pole portion;

[0029] Figure 4 is a side view of the swivelling joint of Figure 1 , shown with an attached light pole portion;

[0030] Figure 5 is a cross section through the swivelling joint of Figure 1 , without an attached light pole portion;

[0031] Figure 6 is a cross section through the swivelling joint of Figure 1 following attachment of a light pole portion to a second member of the swivelling joint.

[0032] Figure 7 is a side view of a second member of a prior art Maxis™ joint;

[0033] Figure 8 is a side view of a second member of the swivelling joint of Figure 1 ;

[0034] Figure 9 is a cross section through the second member of the prior art Maxis™ joint of figure 7, looking down through line X-X;

[0035] Figure 10 is a cross section through the second member of Figure 8, looking down through line Y-Y;

[0036] Figure 11 is a cross section through the second member of the prior art Maxis™ joint of figure 7, looking up through line X-X; and

[0037] Figure 12 is a cross section through the second member of Figure 8, looking up through line Y-Y.Detailed Description of Preferred Embodiments

[0038] Referring to the Figures, there is shown a swivelling joint 10 having a first member 20, a second member 50, and a third member 80.

[0039] The first member 20 is associated with a first leg 22, which is oriented in a longitudinal direction. The first leg 22 terminates at a pole receiving aperture 24, which forms a cylindrical sleeve arranged to connect to a pole (such as the base of a light pole). The first leg 22 has a cylindrical engagement portion 26 near the pole receiving aperture 24, the cylindrical engagement portion 26 having a larger outer diameter than the remainder of the first leg 22. The cylindrical engagement portion 26 has two threaded apertures for receiving grub screws 28, the grub screws 28 acting to lock the first leg 22 onto the pole. An annular rubber cap 30 assists in providing a seal between the first leg 22 and the pole.

[0040] The first member 20 has a first bearing member 32 located at an upper end of the first leg 22, remote from the pole receiving aperture 24. Thefirst bearing member 32 has an annular outer flange 34, the outer flange 34 defining a plane oriented at an angle relative to the longitudinal axis of the first leg 22. An offset angle can be defined as the angle between the longitudinal axis of the first leg 22 and a line perpendicular to the plane of the outer flange 34. In the embodiment of the drawings the offset angle is 45°.

[0041] The outer flange 34 has a generally circular outer perimeter 36, the diameter of which can be defined as D2.

[0042] The outer flange 34 has a plurality of recesses 38 spaced around the outer perimeter 36. In the embodiment of the drawings the outer flange 34 has an uppermost portion 40 without recesses located therein, and eight recesses 38 equally spaced around the remainder of the outer perimeter 36.

[0043] A cylindrical locating shoulder 42 extends upwardly from an internal rim of the outer flange 34. The cylindrical locating shoulder 42 has an axis perpendicular to the plane of the outer flange 34.

[0044] It will be appreciated that an internal surface of the cylindrical locating shoulder 42 represents an opening 43 of the first bearing member 32, which is in communication with the inside of the first leg 22.

[0045] The second member 50 is associated with a second leg 52, which is oriented in the longitudinal direction when in the orientation shown in the drawings. The second leg 52 is generally cylindrical, with an inside diameter Di and an outside diameter D4. The second member 50 has a second bearing member 54 located at a lower end of the second leg 52. The second bearing member 54 has an upper surface 56 having a generally square outer perimeter 57. The upper surface 56 locates in a plane oriented at an angle relative to the longitudinal axis of the second leg 52. The angle between the longitudinal axis of the second leg 52 and a line perpendicular to the plane of the upper surface 56 is the same offset angle as that of the first member 20.

[0046] The side dimension of the outer perimeter 57, that is the length of square L of the upper surface 56, is slightly greater than D2.

[0047] The second bearing member 54 has side walls 58 which extend downwardly from outer edges of the upper surface 56, the side walls 58 being perpendicular to the upper surface 56. The side walls 58 include an uppermost side wall 60, a lowermost side wall 62, and two connecting side walls 64.

[0048] The uppermost side wall 60 passes within a nominal cylinder defined by the outside of the second leg 52. The lowermost side wall 62 extends radially forward of the nominal cylinder defined by the outside of the second leg 52.

[0049] The second leg 52 is joined to the second bearing member 54 via a connection portion 66. The connection portion 66 has an outwardly cylindrical upper portion 68, the outwardly cylindrical upper portion 68 having an outer diameter slightly less than that of the second leg 52. The connection portion 66 has an internally cylindrical upper region 69, which represents a lower internal cylindrical portion of the second member. The internally cylindrical upper region 69 has an inner diameter slightly less than Di. An internal shoulder 70 is thus formed between the second leg 52 and the internally cylindrical upper region 69. A tapered outer shoulder 72 is also formed between the second leg 52 and the outwardly cylindrical upper portion 68.

[0050] In the embodiment shown the internally cylindrical upper region 69 of the connection portion 66 extends axially further than the outwardly cylindrical upper portion 68.

[0051] The connection portion 66 has a flared lower portion 74 having an outer wall 77, which connects the outwardly cylindrical upper portion 68 to the upper surface 56 of the second bearing member 54.

[0052] The uppermost side wall 60 extends away from the flared lower portion 74 near the outwardly cylindrical upper portion 68 at the offset angle.

[0053] A bolt receiving aperture 76 extends through the outwardly cylindrical upper portion 68. The bolt receiving aperture 76 is arranged to receive a pole securing bolt 78. A cylindrical light pole portion 51 can be introduced into the second leg 52 and internally cylindrical upper region 69 of the connection portion 66 and be prevented from axial movement by the pole securing bolt 78.

[0054] It will be appreciated that an internal edge of the connection portion 66 represents an opening 75 of the second bearing member 54, which is in communication with the inside of the second leg 52.

[0055] The third member 80 is formed from a plate. It has a generally square outer perimeter 82, sized to locate immediately inside the side walls 58 of the second bearing member 54. It has a generally circular internal aperture 84, sized to locate about the first leg 22.

[0056] The arrangement is such that the swivelling joint 10 can be assembled with the outer flange 34 of the first bearing member 32 bearing against an internal face of the second bearing member 54, and with the third member 80 bearing against a downwardly facing surface of the outer flange 34. It will be appreciated that the first bearing member 32 and the third member 80 are both located within the side walls 58 of the second bearing member 54.

[0057] The second member 50 and the third member 80 are connected by connecting bolts 86. The second member 50 has two first bolt-receiving apertures passing through the upper surface 56 of the second bearing member 54, a respective first bolt-receiving aperture located near the corner of the lowermost side wall 62 and each of the connecting side walls 64. The second member 50 has two second bolt-receiving apertures 90 passing through the upper surface 56 of the second bearing member 54, arespective second bolt-receiving aperture 90 located near the corner of the uppermost side wall 60 and each of the connecting side walls 64.

[0058] The third member 80 has four internally threaded bolt-receiving apertures 92, one located in each corner of the third member 80.

[0059] Each of a first pair of connecting bolts 86 is arranged to pass through a first bolt receiving aperture of the second member 50 and to be received in a respective internally threaded bolt-receiving aperture 92. Similarly, each of a second pair of connecting bolts 86 is arranged to pass through a second bolt receiving aperture 90 of the second member 50 and to be received in a respective internally threaded bolt-receiving aperture 92.

[0060] It will be appreciated that when all four connecting bolts 86 are thus arranged then the second member 50 will be connected to the third member 80. It will further be appreciated that the connecting bolts 86 are located outside the outer perimeter 36 of the first bearing member 32.

[0061] When the connecting bolts 86 are tightened, each of the second bearing member 54 and the third member 80 bear against the first bearing member 32. The resulting friction restricts rotation of the second member 50 relative to the first member 20.

[0062] When the connecting bolts 86 are loosened, the second member 50 is able to rotate about the first member 20, around an axis which is oriented at the offset angle relative to the longitudinal direction.

[0063] Two pin receiving apertures 94 extend through the upper surface 56 of the second bearing member 54, positioned such that when the second bearing member 54 is located over the first bearing member 32 then the pin receiving apertures 94 align with a recess 38 in the outer flange 34. Two pin receiving recesses 96 extend from the generally circular internal aperture 84 of the third member 80. It will be appreciated that a securing pin 98 can be inserted through an aligned pin receiving aperture 94, recess 38 and pinreceiving recess 96 to further prevent rotation of the second member 50 relative to the first member 20.

[0064] It will be appreciated that each of the first pair of connecting bolts 86 has an axis about which it rotates to be tightened or loosened, with the axes passing well outside the second leg 52.

[0065] By way of contrast, each of the second pair of connecting bolts 86 has an axis about which it rotates to be tightened or loosened, with the axes passing close to the second leg 52.

[0066] Each of the second pair of connecting bolts 86 has a bolt head 100. It will be appreciated that with the uppermost side wall 60 so close to the nominal cylinder of the second leg 52 there is limited space to enable the bolt head 100 to seat against a flat portion of the upper surface 56 of the second bearing member 54. There is even less space to enable a tool such as a spanner to be introduced around the bolt head 100.

[0067] In order to allow securing of the second member 50 to the first member 20 without increasing the cross-sectional dimension of the swivelling joint 10, the second member 50 is provided with two channels 102. Each of the channels 102 is part-cylindrical, and represents a ‘cut out’ in an outer wall of the connection portion 66. The arrangement is such that a nominal cylinder having a diameter D2 greater than the largest transverse dimension of the bolt head 100 extends along an axis aligned with an axis of the connecting bolt 86. The channel 102 represents the boundary of this nominal cylinder. In the embodiment shown, the bolt head 100 is sufficiently close to the second leg 52 that a nominal cylinder having a diameter equal to the largest transverse dimension of the bolt head 100 will extend within the channel 102.

[0068] The channels 102 extend through the flared lower portion 74 and into the outwardly cylindrical upper portion 68.

[0069] The present invention represents a modification of the Maxis™ joint. Figures 7, 9 and 11 show representations of an equivalent second member 250 of a Maxis™ joint, with figures 8, 10 and 12 showing the same views of the second member 50 of the presently described embodiment.

[0070] Of particular note is the wall thickness of the outwardly cylindrical upper portions 68, 268 of the respective connecting portions 66, 266 of the second members 50, 250. Figure 11 shows the relevant wall thickness 271 of the second member 250, being constant.

[0071] Figure 12 shows the wall thickness 71 of the second member 50. It will be noted that there is a significant narrowing of the wall thickness 71 at the channel 102. It will be appreciated that this leads to a corresponding loss of strength in the connection portion 66.

[0072] The development and use of the Maxis™ joint has proceeded on the generally accepted principle that such a loss of strength is unacceptable. As a result, the wall thickness 271 determines a maximum depth of the channel 202 in the Maxis™ joint, which in turn determines a minimum length of square L of the upper surface 256 of the second bearing member 252. This results in a minimum L:Di ratio for the Maxis™ joint of 2.74:1 .

[0073] By way of contrast, the present invention has been able to achieve a minimum L:Di ratio for the Maxis™ joint of 2.2:1 by allowing narrowing of the wall thickness 71 without the narrowed wall becoming susceptible to failure.

[0074] Achieving an L:Di ratio for the Maxis™ joint of less than 2.6 :1 allows for a further feature of the swivelling joint 10, that is, the inclusion of a vibration dampening sleeve 110.

[0075] The second leg 52 has an upper lip 112 at an upper end thereof. The upper lip 112 has an internal diameter Ds which is less than Di , and greater than or equal to that of the internally cylindrical upper region 69. The result is that the second leg 52 has an internal cylindrical portion 114 havingan internal diameter Di , with the internal cylindrical portion 114 being bordered at an upper end by the upper lip 112 and at a lower end by the internal shoulder 70. The vibration dampening sleeve 110, having an outer diameter of Di and an inner diameter less than Ds, can be located in the internal cylindrical portion 114 as shown in Figure 6. The upper lip 112 acts as a restraining ridge which retains the vibration dampening sleeve in position. The internal shoulder 70 acts as a lower restraining ridge.

[0076] The light pole portion 51 can have a maximum outer diameter equal to the internal diameter of the vibration dampening sleeve 110. In this way, the light pole portion 51 can be spaced from the upper lip 112 and also spaced from the internally cylindrical upper region 69. In this arrangement, there is no metal to metal contact between the light pole portion 51 and the second member 50, all contact being through the vibration dampening sleeve.

[0077] In order to eliminate metal to metal contact, the light pole portion 51 has an aperture 116 arranged to locate around a pole securing bolt 78 and to provide an air gap between the pole securing bolt 78 and the light pole portion 51 .

[0078] It has been found that a ratio of L:Ds between 2.4:1 and 2.6:1 allows for optimal sizing of the vibration dampening sleeve 110.

[0079] The second member 50 has an earth-wire receiving portion 120 mounted near the top of the second leg 52. The light pole portion 51 has an earth-wire supporting bracket 122 located, in use, above the second leg 52. An earth-wire 124 connects the earth-wire receiving portion 120 to the earthwire supporting bracket 122. In this way the pole portion 51 received within the second member 50 is electrically connected to the second member 50 even though there is no other metal to metal contact.

[0080] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims

Claims1 . A swivelling joint including a first member, a second member, and a third member; the first member being associated with a first leg, the first leg having a longitudinal direction, the first member having a first bearing member that is oriented at an acute angle relative to the longitudinal direction of the first leg, the first bearing member including an opening in communication with the first leg; the second member being associated with a second leg, the second leg having a longitudinal direction, the second member having a second bearing member that is oriented at an acute angle relative to the longitudinal direction of the second leg, the second bearing member including an opening in communication with the second leg; the second leg having an internal cylindrical portion arranged to receive a cylindrical light pole portion, the internal cylindrical portion having an internal diameter Di; the first bearing member having a generally circular outer perimeter, the outer perimeter having a diameter D2; the second bearing member having a generally square outer perimeter, the square outer perimeter having a side dimension L; the third member having a generally square outer perimeter; the first bearing member being located generally between the second bearing member and the third member; the swivelling joint including a first pair and a second pair of connecting bolts; each bolt being arranged to pass through aligned apertures in the second bearing member and the third member, the bolts being arranged to locate outside the diameter of the first bearing member; wherein each of the first pair of connecting bolts has an axis about which it rotates, the axis of each of the first pair of connecting bolts passing outside the second leg; and each of the second pair of connecting bolts has an axis about which it rotates, each of the second pair of connecting bolts having a head with a maximum transverse dimension;and wherein the second member includes two channels, such that a nominal cylinder extending along an axis of one of the second pair of connecting bolts and having a diameter equal to or greater than the maximum transverse dimension of the respective connecting bolt head extends within a respective channel; wherein L > D2; and the ratio of L: Di is between 2.2:1 and 2.6:1.

2. A swivelling joint as claimed in claim 1 , wherein the internal cylindrical portion has an upper lip having a diameter D3, D3 being less than Di.

3. A swivelling joint as claimed in claim 2, wherein the internal cylindrical portion of the leg abuts a lower internal cylindrical portion of the second member, the lower internal cylindrical portion of the second member having a diameter less than or equal to the diameter D3 of the upper lip.

4. A swivelling joint as claimed in claim 2 or claim 3, wherein the ratio of L:Ds is between 2.4:1 and 2.6:1.

5. A swivelling joint as claimed in any one of claims 2 to 4, wherein the swivelling joint includes a vibration dampening sleeve having an inner diameter less than D3.

6. A swivelling joint as claimed in any preceding claim, wherein the swivelling joint includes a pole securing bolt which extends radially through a lower internal cylindrical portion of the second member.

7. A swivelling joint as claimed in any preceding claim, wherein the second member includes a connection portion connecting the second bearing member to the second leg, the connection portion having a flared lower portion.

8. A swivelling joint as claimed in claim 7, wherein the channels extend within outer walls of the flared lower portion.

9. A swivelling joint as claimed in claim 8, wherein the connection member includes an outwardly cylindrical upper portion, and wherein the channels extend into the outwardly cylindrical upper portion.

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