WO1996029484A1

WO1996029484A1 - Hanger bracket

Info

Publication number: WO1996029484A1
Application number: PCT/GB1996/000599
Authority: WO
Inventors: Kevin Brooks; Robert Butcher; Andrew Reynolds
Original assignee: Klockner-Moeller Gmbh
Priority date: 1995-03-17
Filing date: 1996-03-15
Publication date: 1996-09-26
Also published as: GB9505411D0; AU5010496A; GB2298966B; ZA962125B; EP0815331A1; GB2298966A

Abstract

A hanger bracket (1) located on a threaded, vertical rod (R) and secured to busbar (b) of H-shaped cross section. Bracket (1) has a lower plate portion (3) having ends engaging underneath flanges (f) of the busbar with upper plate (2) clamped to the top of the busbar (b) on tightening of nuts (n1, n2, n3) in a manner which should be evident.

Description

HANGER BRACKET

This invention relates to a hanger bracket more particularly, but not exclusively, for a busbar.

It is known to suspend busbar lengths from ceilings or overhead mounting structures using brackets connected to vertical, threaded support rods extending downwardly from the ceiling or overhead mounting structure. Such brackets have a lower plate portion which in use extends horizontally across the busbar section spanning the busbar, with each end of the plate portion engaging in an associated longitudinal groove provided in a top portion of the busbar. The busbar section may be generally of an H- shape and the lower plate portion of the bracket may be introduced into the open top of the busbar section and rotated through 90" so that the ends of the plate portion engage into the grooves at the top of the busbar. The bracket has an integral upper plate portion extending parallel to the lower plate portion and a circular hole is provided in the lower plate portion which is coaxial with a similar hole in the upper plate portion, said holes being for receiving a vertical, threaded support rod with nuts provided thereon to attach the bracket to the rod. In order to render the engagement of the bracket between the vertical support rod and the busbar section secure it is necessary to prevent the bracket and in particular the lower plate from twisting or rotating relative to the busbar section. Should the bracket rotate sufficiently relative to the busbar the ends of the lower plate portion could disengage from the associated grooves so that the busbar would no longer be supported by the bracket. In order to accomplish said secure fitting, the bracket is provided with two vertical opposed parallel walls each carrying a hook portion mounted thereto by an associated threaded bolt, which allows the distance of each hook portion from the associated wall portion to be varied for fitting and tightening of the hook portions on the busbar to which the bracket is being attached. The arrangement of the bracket is such that once the lower plate portion has been positioned correctly in the grooves in the busbar section the hook portions have to be located over associated, outside longitudinal edges or flanges of the busbar and the bolts have to be tightened up pulling the hook portions towards one another, thus tightly engaging the bracket onto the busbar section. Of course, depending upon the length of busbar being suspended several brackets may be required to be positioned along the top of the busbar, each bracket being connected to an associated vertical rod, as aforedescribed.

The Applicant believes that the aforedescribed bracket tends to be disadvantageous in some respects. The engaging operation involves: the bracket being rotated about the vertical rod until the ends of the lower plate portion engage respective grooves; tightening of the nuts provided on the vertical rod; locating the hook portions over the longitudinal outside edges of the busbar, and tightening of the bolts connecting the hook portions to the vertical wall portions of the bracket. Thus, in addition to the vertical rod and nuts, the hanger arrangement requires the bracket, separate hook portions and separate threaded bolts mounting the hook portions to the vertical wall portions of the bracket. It is believed that a successful suspension of a busbar conductor length may be accomplished using a hanger bracket which is simplified in at least some respects and which may require fewer parts and/or less complicated assembly. It may also be possible to produce a less expensive hanger bracket that may be secured to the busbar more easily with less risk of the engagement of the hanger bracket with the busbar becoming loose and requiring a reduced number of tightening operations.

An object of the present invention is to provide a hanger bracket which is improved in at least some respect and/or which at least alleviates one or more of the afore- mentioned, or other, disadvantages associated with hanger brackets.

According to the present invention there is provided a hanger bracket for use in suspending a busbar or the like, said hanger bracket comprising a lower plate portion and an upper plate portion, the arrangement being such that the lower plate portion can be introduced into an open top of the busbar or the like and moved or rotated relative thereto until ends thereof engage into associated grooves or under flanges of said busbar or the like, said upper plate portion being movable downwardly relative to the lower plate portion to clamp the bracket to said busbar or the like.

Further according to the present invention there is provided the combination of a busbar or the like and one or more hanger brackets in accordance with the immediately preceding paragraph.

In one embodiment of the present invention the upper and lower plate portions will each be provided with a hole allowing the insertion of a vertical threaded rod such that the lower plate portion can be introduced into the open top of the busbar with the upper plate portion arranged thereabove. The upper and lower plate portions may be secured to the vertical rod by nut means.

Preferably, at least one of the upper and lower plate portions will be provided with at least one strip or flange means which depends downwardly or upwardly over or beyond the opposing plate portion in a clamped position. In one embodiment, the upper plate portion has two opposed downwardly depending strips or flange means which straddle the edges of the lower plate portion in the clamped position and which depend downwardly into the open top of the busbar or the like. Usually, the strip/s or flange means will span the width of the busbar or the like and fit snugly into the open top thereof as an aid to prevent twisting or rotating of the busbar relative to the bracket. Preferably, the upper plate portion has ends which seat on the top of the busbar or the like so that the busbar is sandwiched or clamped between the upper and lower plate portions.

It is advantageous that, in some embodiments, the busbar or the like may be securely clamped to the bracket and to a, or the, vertical rod by a single tightening operation namely the tightening up of the upper plate portion with respect to the lower plate portion by rotation of the nut means on the rod. In the previous prior art arrangement already referred to, the plate portions have to be secured to the threaded rod and, after this tightening up operation, two further operations are required to tighten the loose hook means onto the outside longitudinal edges of the busbar. Additionally, the prior art arrangement would seem disadvantageous in its overall aesthetic aspects including the exposed hook portions whereas the upper plate portion in accordance with embodiments of the present invention will fit very snugly into the top of the busbar or the like.

Still further according to the present invention there is provided a method of suspending a busbar or the like using a hanger bracket having upper and lower plate portions, said method comprising: introducing the lower plate portion into an open top of said busbar or the like and moving or rotating the lower plate portion relative to the upper plate portion and the busbar, thereby engaging ends of the lower plate portion into associated grooves or under flanges of said busbar or the like; and moving the upper plate portion downwardly relative to the lower plate portion to thereby clamp the bracket to said busbar or the like. Preferably, the lower plate portion and upper plate portion are connected to a threaded vertical rod by means of nuts and preferably, the upper plate portion is moved downwardly relative to the lower plate portion by tightening of said nuts.

Other advantageous features will be evident from the following description and drawings.

An embodiment of a hanger bracket in accordance with the present invention will now be described by way of example only with reference to the accompanying much simplified drawings in which:

FIGURE 1 shows front and side elevations of a prior art hanger bracket;

FIGURE 2 shows a first embodiment of a hanger bracket in accordance with the present invention, mounted on a threaded vertical rod and positioned above a busbar ready for engagement therewith;

FIGURE 3 is a view similar to FIGURE 2 showing an intermediate assembly position of the hanger bracket with the busbar, a lower plate portion of the hanger bracket engaging the busbar;

FIGURE 4 shows a view similar to FIGURES 2 and 3 with the hanger bracket fully engaged with the busbar;

FIGURE 5 shows an upper plate portion of the hanger bracket in orthographic projection;

FIGURE 6 shows the lower plate portion of the hanger bracket in orthographic projection, and

FIGURES 7 and 8 show orthographic views of upper and lower plate portions of a second embodiment of the hanger bracket.

FIGURE 1 shows a prior art hanger bracket 100 having a generally rectangular (albeit with rounded corners) plate portion 101 integrally connected to an upper, parallel, overlying plate portion 102, by means of a vertical rear wall portion 103. A central hole 101a is provided in the lower plate portion 101, said hole being coaxial with a similar hole 102a provided in the upper plate portion 102. In use of the bracket 100 for suspending a busbar (not shown) a vertical threaded rod (not shown) will extend through the holes 102a and 101a in the plate portions 102, 101 and the bracket will be secured thereto by means of nuts on the threaded rod. The bracket 100 is provided with two similar, parallel, integral side walls 104a, 104b each carrying a hook portion 105,106 mounted thereto by an associated threaded bolt 107,108 passing through a threaded receiving hole 109,110 in a manner which should be evident from FIGURE 1. Appropriate rotation of the bolt heads 107a, 108a allows the hook portions 105,106 to be moved further apart from one another in order to engage over outside longitudinal edges or flanges (not shown) of the the busbar, once ends of the lower plate portion 101 have been engaged in inner grooves (or under inner flanges) provided on a top portion of the busbar.

In order to engage the ends of the lower plate portion 101 into grooves or under flanges of the busbar, the bracket 100 is introduced into an open top of said busbar with the axis of the lower plate portion 101 extending parallel to the axis of the busbar. Once the lower plate portion 101 is level with said grooves or is at a level just below said flanges (where provided) the bracket 100, and thus the lower plate portion 101, can be rotated about the axis 111 of the vertical rod in order to engage the ends of the lower plate portion 101 into the grooves or under the flanges, as the case may be. Hook portions 105, 106 can then be located over the outside longitudinal edges of the busbar and the threaded bolts 107,108 tightened with washers 112,113 being positioned between the bolt heads 107a, 108a and the hook portions 105,106 in the manner as shown in the drawings. Thus, the hook portions are pulled towards one another tightly engaging the bracket 101 onto the busbar section. It is believed that the bracket 101 tends to be disadvantageous in some respects as mentioned in the introductory part of this specification.

FIGURES 2 to 6 show a first embodiment of a hanger bracket 1 in accordance with the present invention. FIGURES 2 to 4 show the hanger bracket 1 located on a vertical threaded rod R and three stages A,B,C of engaging the bracket securely onto a busbar b of generally H-shaped cross-section and shown in simplified form with conductor lengths omitted for ease of illustration.

FIGURE 2 shows the first stage in clamping the bracket 1 to the busbar b. The hanger bracket comprises an upper plate portion 2 and a lower plate portion 3. Views of the upper plate portion 2 are shown in FIGURE 5 and views of the lower plate portion 3 are shown in FIGURE 6, the scale of FIGURES 5 and 6 being larger than that used in FIGURES 2 to 4.

It is to be noted that the bracket 100 shown in FIGURE 1 is for use with a busbar having a narrower span than the span s shown in FIGURE 2. The span of the busbar will depend upon the rating of the busbar and increases with increasing rating. Thus the bracket 100 is for use with a busbar of much lower rating than the busbar b although the same principle of attachment is applied with busbars of higher rating. As should be evident from FIGURES 2 to 4 the hanger bracket 1 is attached to the busbar b by introducing the lower plate portion 3 into the open top o of the busbar b. The lower plate 3 is then rotated through 90" until the ends of the plate portion 3 engage underneath flanges f of the busbar to reach position B as shown in FIGURE 3. Upper plate 2 can then be lowered to clamp the bracket 1 to the busbar b which is position C shown in FIGURE 4. This clamping operation of the bracket 1 to the busbar b will be described in more detail after the upper and lower plate portions 2 and 3 have been described.

FIGURE 5 shows an inverted plan view of the plate portion 2 with an end view and inverted front view being depicted in third angle projection. The upper plate portion 2 is of galvanised steel and has an overall length

2a with rounded corners 2b.

In the present instance, the length 2a may be 24cm although this dimension will vary depending upon the rating of the busbar. The thickness 2c of the plate portion 2 will be about 3mm and the diameter of central hole 2d, which in use receives the threaded vertical rod R, will be 10.5mm. The plate portion 2 has opposed integral strips 2e and 2f extending downwardly in use as shown in FIGURES 2 to 4 said strips extending at right angles to the main plane of the plate portion 2. The strips 2e and 2f finish short of each end of the plate portion 2 by a distance 2g and 2h, each distance 2g and 2h being of about 27mm. The overall width 2i of the plate portion 2 is 38mm. As will be evident from FIGURES 2 to 4, in practice, the length 2j of each strip will fit snugly into the open top 0 of the busbar b with the strips 2e and 2f depending downwardly into the open top of the busbar.

The lower plate portion 3 has an overall length 3a which in this instance is 20cm and a width 3b of 3cm.

Central hole 3c is of the same width dimension as the threaded rod R and the same dimension as hole 2d in the upper plate portion.

FIGURE 5 shows an upper plan view of plate portion 3 with a front view being shown therebelow. The thickness 3d of the plate will be about 5mm. It is to be noted in this embodiment, that two diagonally opposite corners 3e and 3f have been rounded to allow a smooth introduction of the lower plate portion 3 underneath the associated flanges f as the lower plate portion is rotated or twisted about the vertical rod R. The rounded corners 3e and 3f facilitate engagement of the flanges in a manner which should be self- evident. The right-angle corners 3g and 3h could also be rounded but it is believed that it may be advantageous to leave them as right-angled in order to provide a more secure engagement at least in a rotational sense opposite to the rotational direction applied on engaging the lower plate portion underneath flanges f. Curved arrow X indicates the rotational sense employed for engaging the ends of the plate portion 3 underneath the flanges f. Engagement of the hanger bracket 1 onto the busbar b should be evident from FIGURES 2 to 4. In FIGURE 2, the upper plate portion 2 is shown connected to threaded rod R with two securing nuts nl and n2 being located above the plate portion. Lower plate portion 3 is provided at the lower end of rod R by means of locating nut n3. Initially the longitudinal axis 3i of the lower plate portion 3 is arranged at right angles to the axis 2m of the upper plate portion 2 and parallel to the axis of the busbar b. The upper and lower plate portions 2,3 are spaced apart a sufficient amount to enable the lower plate portion to be introduced to the open top 0 of the busbar b without engagement of the upper plate portion with the busbar. The busbar b is introduced upwardly to the hanger bracket 1 in direction of arrow D (see FIGURE 2) and once the lower plate portion 3 is at a level just below the flanges f of the busbar, the lower plate portion is rotated through 90" (in direction of arrow X as shown in FIGURE 5) until the end portions of the plate portion 3 engage underneath the flanges f, as shown ϊn FIGURE 3. In order to secure the bracket 1 to the busbar b, and thus the busbar to the vertical support rod, nuts nl,n2 and n3 can be tightened moving the upper plate portion 2 downwardly relative to the lower plate portion 2 until the strips 2e and 2f fit snugly inside the open top 0 of the busbar b and overlap the longitudinal edges of the lower plate portion 3 in a manner as shown in FIGURE 4. Arrow E shows the direction of movement of the upper plate portion 2 relative to the lower plate portion 3. In this position it is to be noted that the underside of the projecting ends 2k and 21 seat on the upper flat surfaces of the flanges f of the busbar b so that the flanges f are clamped tightly between the upper plate portion 2 and the lower plate portion 3, the downwardly depending strips 2e and 2f restraining any rotation of the bracket 1 relative to the busbar about vertical rod R.

FIGURES 7 and 8 show alternative upper and lower plate portions 2',3*. In each case, an inverted plan view of the plate portion 2' ,3' is shown above a front view of the plate portion. The length 2'a of the plate portion 2' is 22cm and the length 2'b of each strip 2'c will be 19cm. The diameter of the central hole 2'd will be chosen to suit the diameter of the threaded rod R. The projecting ends 2'e and 2'f of the plate portion 2 are semi-circular. The lower plate portion 3 has an overall dimension 3'a of 20.2cm with the length 3'b of the strips 3'c and 3'd being 10cm. The ends 3'e and 3'f are semi-circular as shown and the central hole 3'g will match the diameter of the central hole 2'd. The thickness 2'g of the plate portion 2' is 3mm with each strip 2'c,2'd extending a distance 2'h at right angles to the main plane of the plate portion 2' . The thickness 3h of the plate portion 3 is 3mm with the strips 3'c and 3'd extending a distance 3i of 15mm at right angles to the main plane of plate portion 3' . It is believed that the particular relative dimensions of the upper and lower plate portions 2'.3' of the hanger bracket 1 are particularly advantageous. It is to be understood that the scope of the present invention is not to be unduly limited by the particular choice of terminology and that a specific term as used herein may be replaced or supplemented by an equivalent or generic term. For example, the term plate portion could be replaced by "portion" or "member". Further it is to be understood that the individual features, method or function relating to the hanger bracket, or parts thereof might be individually or in combination patentably inventive. The singular may include the plural or vice versa. Moreover, any disclosure in this specification of a range for a variable or parameter shall be taken to include a disclosure of any selectable or derivable sub-range within that range and shall be taken to include a disclosure of any value for the variable or parameter within or at an end of the range or sub-range.

Claims

1. A hanger bracket for use in suspending a busbar or the like, said hanger bracket comprising a lower plate portion and an upper plate portion, the arrangement being such that the lower plate portion can be introduced into an open top of the busbar or the like and moved or rotated relative thereto until ends thereof engage into associated grooves or under flanges of said busbar or the like, said upper plate portion being movable downwardly relative to the lower plate portion to clamp the bracket to said busbar or the like.

2. A bracket as claimed in Claim 1 in which the upper and lower plate portions are each provided with a hole allowing the insertion of a vertical threaded rod such that the lower plate portion can be introduced into the open top of the busbar with the upper plate portion arranged thereabove.

3. A bracket as claimed in Claim 2 in which the upper and lower plate portions may be secured to the vertical rod by nut means.

4. A bracket as claimed in any one of the preceding claims in which at least one of the upper and lower plate portions will be provided with at least one strip or flange means which depends downwardly or upwardly over or beyond the opposing plate portion in a clamped position.

5. A bracket as claimed in Claim 4 in which the upper plate portion has two opposed downwardly depending strips or flange means which straddle the edges of the lower plate portion in the clamped position and which depend downwardly into the open top of the busbar or the like.

6. A bracket as claimed in Claim 4 or Claim 5 in which the strip/s or flange means span the width of the busbar or the like and fit snugly into the open top thereof.

7. A bracket as claimed in any one of the preceding claims in which the upper plate portion has ends which seat on the top of the busbar or the like so that the busbar is sandwiched or clamped between the upper and lower plate portions.

8. A bracket as claimed in any one of the preceding claims in which the busbar or the like may be securely clamped to the bracket and to a, or the, vertical rod by a single tightening operation.

9. A hanger bracket substantially as herein described with reference to FIGURES 2 to 6, or 7 and 8 of the accompanying drawings.

10. A combination of a busbar or the like and one or more hanger brackets as claimed in any one of the preceding claims.

11. A method of suspending a busbar or the like using a hanger bracket having upper and lower plate portions, said method comprising: introducing the lower plate portion into an open top of said busbar or the like and moving or rotating the lower plate portion relative to the upper plate portion and the busbar, thereby engaging ends of the lower plate portion into associated grooves or under flanges of said busbar or the like; and moving the upper plate portion downwardly relative to the lower plate portion to thereby clamp the bracket to said busbar or the like.

12. A method as claimed in Claim 11 in which the lower plate portion and upper plate portion are connected to a threaded vertical rod by means of nuts.

13. A method as claimed in Claim 12 in which the upper plate portion is moved downwardly relative to the lower plate portion by tightening of said nuts.

14. A method of suspending a busbar or the like substantially as herein described.