GB2338498A

GB2338498A - Suspension arrangement for suspending an article from a cavity in a floor or ceiling slab

Info

Publication number: GB2338498A
Application number: GB9912973A
Authority: GB
Inventors: Simon Harvey
Original assignee: GLYNWED ENGINEERED PRODUCTS LI
Current assignee: GLYNWED ENGINEERED PRODUCTS LI
Priority date: 1998-06-04
Filing date: 1999-06-04
Publication date: 1999-12-22
Anticipated expiration: 2019-06-04
Also published as: GB9811923D0; GB9912973D0; GB2338498B

Abstract

A suspension arrangement for suspending an article from a cavity (50,51,52) in a floor or ceiling slab (47) comprises a main body with pivotally attached gripping arms (49), a central bolt, and upper (48) and lower nuts. In use, the lower nut tightens against the main body and the upper nut (48) travels down the bolt causing the gripping arms (49) to pivot in a manner which brings one of their ends into contact with the sides of the cavity (51,52), and the other into abutment with the face of the slab.

Description

2338498 SUSPENSION ARRANGEMENT The present invention relates to a

suspension arrangement. More particularly, but not exclusively, this invention relates to a suspension arrangement for suspending an article from a floor/ceiling slab.

In multi-storey buildings, the ceiling of one storey often serves as the floor for the storey above. Such floor/ceilings often have to bear substantial loads (for example in car parks) and so are typically made from reinforced concrete slabs. These floor/ceiling slabs are prepared by pouring the concrete onto a metal mould forming deck which extends between horizontal support beams of the building framework. The concrete sets and contracts around the deck forming a composite floor/ceiling slab.

The mould forming decks used in such floor/ceiling slabs are usually provided with one or more elongate recesses in their undersides. once the deck is in position a suspension element can be inserted into the recess and engaged with the recess walls. Objects such as light fittings, conduits and decorative panels can then be suspended from the suspension elements.

However, there are a large number of recesses of different sizes and shapes in common use in the building indutry, each of which requires a specific suspension element. This is Potentially dangerous because if a suspension element is used in a recess for which it has not been designed, it could fail unexpectedly or when a load well below the expected limit is hung from it.

1 Accordingly, in a first aspect, the invention provides a suspension arrangement for suspending an article from a floor/ceiling slab and comprising:

a) a mould forming deck forming the base of the slab cast thereon, a portion of the deck having an elongate recess on its underside, the recess having a mouth, a base and sidewalls; and, b) a suspension element comprising a support member and a pivot member pivotally attached to the support member, the pivot member being pivotally adjustable between first and second configurations; the pivot member comprising a gripping arm and an abutment arm; the gripping arm being adapted to be inserted into the recess when the pivot member is in the first configuration and to abut against a recess side wall when in the second configuration so preventing removal of the gripping arm from the recess; the abutment arm being adapted to abut against the underside of the mould forming deck on insertion of the gripping arm into the recess, so pivoting the pivot arm from the first to the second configurations..

The suspension arrangement of the invention has the advantage that it can be used safely with recesses of a variety of different sizes.

Preferably, the suspension arrangement comprises a second pivot member, the second pivot member comprising a second abutment arm and a second gripping arm and being pivotable between first and second configurations; the gripping arms of the pivot member and the second pivot member being arranged to abut opposite side walls of the recess when in the second configuration.

This spreads the load applied to the suspension arrangement equally to both sides of the recess.

The pivot member can be substantially W' shaped having first and second arms connected to a base; the first arm comprising the gripping arm; the second arm comprising the abutment arm and, the pivot member being connected to the support member at the base.

The suspension arrangement can further comprise a locking means for locking the pivot member in the second configuration. The locking means can comprise a nut and a bolt, the bolt having a head which can be inserted into the recess along with the gripping arm when the gripping arm is in a first configuration but cannot be removed from the recess when the gripping arm is in the second configuration, the bolt extending through the support member; the nut being arranged on the bolt on the opposite side of the support member to the head, so that on tightening the nut the support member is urged towards the head.

Preferably the locking means is arranged such that on tightening of the nut the head abuts against the gripping arm urging the gripping arm from the first to the second configuration into contact with the side wall.

1.

In a further aspect the invention provides a suspension arrangement for suspending an article from a floor/ceiling slab and comprising: a) a mould forming deck forming the base of a slab cast thereon, a portion of the deck having an elongate recess on its underside, the recess having a mouth, a base and sidewalls; and, 1 b) a suspension element comprising a pivot member and a locking member, the pivot member being pivotally adjustable between first and second configurations with respect to the locking member; the pivot member comprising a gripping arm and an abutment arm; the gripping arm being adapted to be inserted into the recess when the pivot member is in the first configuration and to abut against a recess side wall when in the second configuration, so preventing removal of the gripping -arm from the recess; the locking member comprising a bolt having a prolate head which can be inserted into the recess when in a first orientation with the long axis of the head parallel to the long axis of the recess; but cannot be removed from the recess when in a second orientation with the long axis of the head normal to the long axis of the recess; the locking member being arranged such that on turning the locking member from the first to the second orientation the head abuts against the gripping arm so pivoting the gripping arm from the first to the second configuration and urging the gripping arm in to contact with the side wall.

The invention will now be described by way of example only and not in any limitative sense, in which figures la and lb show a known suspension element; figure 2 shows a first embodiment of the suspension arrangement of the invention in exploded perspective view; figure 3 shows a support means of the invention in perspective view; figures 4a-4c show a method of engaging a suspension element of a first embodiment of the invention and a mould forming deck; figure 5 shows a second embodiment of the invention in plan view; figure 6 shows a third embodiment of the invention in plan view.

Shown in figure la is a known suspension apparatus 1 comprising a suspension element 2 and mould forming deck 3. Located within the mould forming deck is an elongate recess 4. The suspension element 2 and elongate recess 4 are correctly matched with the side walls of the suspension element 2 engaging with the side walls of the recess 4 over an extended area. The suspension element 2 and recess 4 will only disengage when very high loads are applied to the suspension element 2.

Shown in figure lb is the suspension element 2 shown i figure la now engaged with a different recess 5. The recess 5 and suspension element 2 are badly matched with all of the weight of the suspension element 2 being distributed around the mouth 6 of the recess 5. The suspension element 2 will disengage from this recess 5 when a much lower load is applied than when engaged with the recess 4 shown in' figure la.

Shown in figure 2 is a suspension element 7 for engagement with a mould forming deck according to the invention. The suspension element 7 comprises a support member 8 which comprises a rectangular planar base 9 having long and short axes. Side walls 10, 11 extend upwardly from the edges 12, 13 of the base 9 parallel to the long axis. The support member 8 is typically manufactured from a single rectangular sheet of metal which is bent into the correct shape. This results in a support member 8 which is generally U shaped in cross section perpendicular to its length, having rounded corners joining the base 9 and side walls 10, 11.

Located on the inner faces of the side walls are four protrusions 14-17 arranged in opposite pairs to form first and second pivots. Interengaged with these pivots are first and second pivot members 18, 19. Each of these pivot members 18, 19 is substantially W' shaped in cross section in a plane normal to the short axis of the base. Each pivot member 18, 19 comprises a gripping arm 20 and an abutment arm 21, the angle between the arms 20, 21 being less than 90 degrees. Preferably the angle between the arms 20, 21 is between 50 and 80 degrees. More preferably the angle between the arms 20, 21 is between 70 and 80 degrees. The arms 20, 21 are connected together by a rounded base 22. Typically, each pivot member 18, 19 is manufactured from a single rectangular metal sheet bent to the correct shape. The gripping arm 20 of each pivot member 18, 19 is adapted to grip the side walls of a recess in the mould forming deck. The abutment arm 21 of each pivot member 18, 19 is adapted to abut against the mould forming deck when the suspension element 7 and mould forming deck are urged in to contact, so pivoting the gripping arm 20.

Each rounded base 22 is suspended between a pivot formed by the protrusions 14-17 located on the inner faces of the side walls 10, 11. The pivot members 18, 19 are free to rotate between first and second positions. In the first position (as shown in figure 2) the gripping arm 20 extends vertically upwards normal to the plane of the base 9 of the support member 8. The abutment 21 is inclined to the support member base 9 with a portion 24 located above the side walls 10, 11 as shown. In the second position (not shown) the abutment arm 21 is parallel to the base 9 and the gripping arm 20 extends away from the normal to the base 9. When in either of the first and second positions one of the arms 20, 21 of the pivot member abuts against the protrusions of the base 9, so preventing further movement.

In order to assemble the support member 8 and first and second pivot members 18, 19, the abutment arm 21 of the first pivot member 18 is hooked under protrusions 14, 15 and then slid parallel to the base 9 until the rounded base 22 abuts against the protrusions 14, 15. The first pivot member 18 is then rotated until the gripping arm 20 is normal to the plane of the base 9. The second pivot member 19 cannot be attached by a similar method because when the second arm 21 is hooked under the protrusion 16, 17 and rotated, the rounded base 22 of this member abuts against the first pivot member 18, so preventing the second pivot member 19, from being rotated fully into position. The abutment arm 21 of the second pivot member 19 is therefore provided with an assembly aperture 19a. At the assembly aperture 19a the width of the abutment arm 21 is less than the distance between the protrusion 16, 17. The abutment arm can therefore be inserted directly between the protrusions 16, 17 and then the pivot member 19 slid parallel to the base to the position shown in which the rounded base 22 abuts against the protrusions 16, 17.

Located in the base 9 of the support member 8 between the first and second pivot members is an orifice (not shown). In use, a locking means 26 comprising a bolt 27 is passed through the orifice normal to the plane of the base 9. Attached to the first end 28 of the bolt 27 is a first nut 29 which, when tightened, abuts against the underside of the base 9. Attached to the second end 30 of the bolt 27 is a head 31, in this embodiment the head 31 is a second nut. In the plane normal to the long axis of the bolt 27 the second nut 31 is substantially rectangular in cross section having a pair of short parallel sides 32, 33 and a pair of long parallel sides 34, 35. In the plane normal to both the axis of the bolt 27 and the long sides 34,.35 of the- nut 31, the nut 31 again appears to be rectangular in cross section. However, in a third plane normal to the other two the nut 31 has parallel top and bottom edges 35, 36 with the top edge 35 being substantially longer than the bottom edge 36. A pair of non-parallel sides 37, 38 extend between the top and bottom edges 35, 36. The second nut 31 is adapted so that the perpendicular distance between the gripping arms 20 of the pivot members 18, 19 when the members are in the first position is greater then the length of the short parallel sides 32, 33 and the length of the bottom edge of the nut 36. This distance is however smaller than the length of the top edge 36 of the second nut 31. Located between the second nut 31 and the second end 30 of the bolt 27 are a washer 39 and a third nut 40 for maintaining the second nut 31 in position. The washer 39 and third nut 40 are optional.

Shown in figure 3 is a second support member 41 of a suspension according to the invention. The first and second pivots 42, 43 comprise parallel bars 44, 45 extending between the opposite inside faces of the side walls.

Shown in figures 4a-4c is a method of engaging a moild forming deck 3 and suspension element 7 according to the invention. The mould forming deck 3 comprises first and second outer walls 46, 47 and an elongate recess 48. The recess 48 comprise a mouth 49, a base 50 wider than the mouth 49 and a pair of side walls 51, 52 extending between the base 50 and the mouth 49. In order to engage the mould forming deck 3 and the suspension element 7 the bolt 27 is inserted through the orifice in the base 9. The first nut 29 is 1 threaded onto the first end 28 of the bolt 27 and the second nut 31 threaded onto the second end 30. The pivot members 18, 19 are each rotated to the first configuration with the gripping arms 20 normal to the plane of the base 9. The bolt 27 is rotated until the long sides of the upper face of the second nut 31 are perpendicular to the long axis of the base 9. Once in this configuration the gripping arms 20 of the pivot members 18, 19 and the second bolt 27 can be inserted through the mouth 49 into the recess 48 until the abutment arms 24 come into contact with the outer walls 46, 47- as shown in figure 4a.

As the pivot members 18, 19 are inserted further into the recess 48 the abutment arms 24 press against the outer wal 46, 47 pivoting the pivot members 18, 19 from the first to the second configuration, as shown in figure 4b. Once the pivot members 18, 19 have reached the second configuration the second nut 31 is rotated about its long axis until the long side walls of the second nut 31 are parallel to the long axis of the base 9.

ls As shown in figure 4c the bolt 27 is then pulled downward forcing the second nut 31 into contact with the pivot members 18, 19. The non parallel side walls of the second nut 31 for4ce the gripping arms 20 of the pivot members 18, 19 outwards and into contact with the side walls 51, 52 of the recess 48, so engaging the suspension element 7 and'recess 48. Finally, the first nut 29 is tightened so maintaining the suspension element 7 and recess 48 in engagement.

The same suspension element 7 can be used with a variety of different recesses 48. When used in wide recesses the gripping arms of the pivot members 18, 19 are forced further apart by the second nut 31 to come into engagement with the side walls 51, 52. The pivot members 18, 19 are designed to 1 be resiliently deformable to allow for use in such wide recesses.

Shown in figure 5 is a further embodiment of the invention. The suspension element 53 comprises only one pivot member 54 and an locking means 55. When engaged with the mould forming deck the pivot member 54 engages with one side wall 51 of the recess whilst the locking means 55 engages with the mouth 49 of the recess 48.. Such a suspension element is simple and inexpensive to construct.

Shown in figure 6 is a further embod'Lment of the invention. This embodiment comprises a pivot member comprising a gripping arm and an abutment arm. The angle between the abutment arm and the gripping arm is greater than 900. An aperture (not shown) extends through the abutment arm. Extending through the aperture is a bolt having a prolate head. Threaded on the bolt on the opposite side of the abutment arm to the prolate head is a bolt.

in order to insert the suspension arrangement into the recess the pivot member is pivotted to a first configuration with the gripping arm parallel to the long axis of the bolt. bolt is rotated until the long axis of the head -'s paralle to the long axis of the recess. The gripping ar- and head are then inserted through the mouth into 7-he recess.

once in position the bolt is rotated until the long axis of the bolt head is perpendicular to the long axis of the aperture. This pivots the pivot member to a second configuration with the gripping arm in contact with a side wall. The head is urged into contact with the opposite side wall as shown.

The nut is then threaded along the bolt towards the head locking the suspension assembly in position.

Claims

Claims:

1. A suspension arrangement for suspending an article from a floor/ceiling slab and comprising: a) a mould forming deck forming the base of the slab cast thereon, a portion of the deck having an elongate recess on its underside, the recess having a mouth, a base and sidewalls; and, b) a suspension element comprising a support member and a pivot member pivotally attached to the support member, the pivot member being pivotally adjustable between first and second configurations; the pivot member comprising a gripping arm and an abutment arm; the gripping arm being adapted to be inserted into the recess when the pivot member is in the first configuration and to abut against a recess side wall when in the second configuration so preventing removal of the gripping arm from the recess; the abutment arm being adapted to abut against the underside of the mould forming deck on insertion of the gripping arm into the recess, so pivoting the pivot arm from the first to the second configurations.

2. A suspension arrangement as claimed in claim 1 comprising a second pivot member, the second pivot member comprising a second abutment arm and a second gripping arm and being pivotable between first and second configurations; the gripping arms of the pivot member and the second pivot member being arranged to abut opposite side walls of the recess when in the second configuration.

3. A suspension arrangement as claimed in either of claims 1 or 2 wherein the pivot member is substantially W' shaped, having first and second arms connected by a base, the first arm comprising the gripping arm, the second arm comprising the abutment arm and the pivot member being connected to the support member at the base.

A suspension arrangement as claimed in any one of claims 1 to 3 further comprising a locking means for maintaining the pivot member in the second configuration.

A suspension arrangement as claimed in claim 4 wherein the locking means comprises a nut and bolt, the bolt having a head which can be inserted. into the recess along with the gripping arm when the gripping arm is in a first configuration but cannot be removed from the recess when the gripping arm is in the second configuration; the bolt extending through the support member; the nut being arranged on the bolt on the opposite side of the support member to the head, so that on tightening the nut the support member is urged towards the head.

6.

7.

A suspension arrangement as claimed in claim 5, wherein the locking means is arranged such that on tightening to the nut the head abuts against the gripping arm urging the gripping arm from the first to the'second configuration into contact with the side wall.

A suspension arrangement for suspending an article from a floor/ceiling slab and comprising: a) a mould forming deck forming the base of a slab cast thereon, a portion of the deck having an elongate recess on its underside, the recess having a mouth, a base and sidewalls; and, b) a suspension element comprising a pivot member and a locking member, the pivot member being pivotally adjustable between first and second confi gurations with respect to the locking member; the pivot member comprising a gripping arm and an abutment arm; the gripping arm being adapted to be inserted into the recess when the pivot member is in the first configuration and to abut against a recess side wall when in the second configuration, so preventing removal of the gripping arm from the recess; the locking member comprising a bolt having a prolate head which can be inserted into the recess when in a first orientation with the long axis of the head parallel to the long axis of the recess; but cannot be removed from the recess when in a second orientation with the long axis of the head normal to the long axis of the recess; the locking member being arranged such that on turning the locking member from the first to the second orientation the head abuts against the gripping arm so pivoting the gripping arm from the first to the second configuration and urging the gripping arm in to contact with the side wall.

A suspension arrangement substantially as hereinbefore described with reference to figures 2 to 6 of the accompanying text.