GB2533142A

GB2533142A - Hook arrangement

Info

Publication number: GB2533142A
Application number: GB1422068.5A
Authority: GB
Inventors: Taylor Mark
Original assignee: Ischebeck Titan Ltd
Current assignee: Ischebeck Titan Ltd
Priority date: 2014-12-11
Filing date: 2014-12-11
Publication date: 2016-06-15
Anticipated expiration: 2034-12-11
Also published as: GB2533142B

Abstract

A hook arrangement that is mountable to a construction for selectively engaging and supporting a climbing screen 30. The hook arrangement comprises: a hook 1 pivotally mounted to move between a retracted position (Fig. 2) in which it does not engage the climbing screen and a deployed position (Fig. 1) in which it engages the climbing screen; a biasing means 2 which urges the hook into the deployed position; and a latching mechanism (3, Fig. 2), which is engaged automatically by pivotal movement of the hook from the deployed to the retracted position, to maintain the hook in the retracted position. Preferably, the latching mechanism (3, Fig 2) comprises a catch 4 that is biased towards a first position in which it engages the hook 1 or an element 7 rotatable with the hook. Preferably, the hook is mounted within a housing (11, Fig 2).

Description

Hook Arrangement The present disclosure relates to a hook arrangement, in particular to a retractable hook arrangement for supporting the vertical load of a climbing screen or climbing formwork.

In modern construction, particularly in the construction of high rise buildings it is common to have a central core, which houses lift shafts and stair wells and which provides support to the floors of the construction, wherein the central core and floors are formed by poured concrete. These structures commonly have no external walls.

Generally the central core is built up in a number of steps, with each step corresponding to one or more storeys of the building and comprising a separate pour of concrete. All of the concrete pours need to be contained, in order to hold the concrete in place until it hardens sufficiently to hold its own shape. Such containment is generally effected by use of temporary shuttering, most commonly referred to as formwork.

As the height of the building core increases, the height at which the formwork needs to be provided above ground level increases, wherein each successive pour can only take place after the preceding pour has properly set. For this purpose there exist climbing formwork systems. Climbing formwork systems generally comprise a formwork support assembly, which is supported by climbing rails that are engaged, in use, by fixed supports, which project outwardly from the construction. The fixed supports allow translation of the climbing formwork along the construction. The formwork support assembly generally consists of a platform adapted to extend substantially horizontally and on which is slidably mounted, for horizontal movement, a framework which supports a vertically extending formwork panel. The platform may be located in an initial position and the formwork may be advanced horizontally to a suitable position for the pouring of concrete. After the concrete has been poured and at least partially cured the supporting framework may be moved horizontally to withdraw the formwork from the concrete. The platform, still supporting the framework and the formwork panel may then be translated vertically to a higher position and fixed to the structure that has just been built. The formwork may then be advanced horizontally to the position to a suitable position for a subsequent pouring step.

Moreover, during large periods of construction, the floors supported by the core remain open at their edges. It is only when a facade is introduced that the perimeter of the building is enclosed. Such open floors cause numerous health and safety risks. Workers operating on the exposed floors of the construction are at risk of falling from the construction. Workers or members of the public on the ground are at risk from tools, equipment or debris falling from the exposed floors.

It is therefore known to provide safety screens, which extend around at least a portion of the perimeter of constructions, which effectively provide a temporary façade, and advantageously provide safe working platforms spaced outwardly from the floors. These safety screens are advantageously moveable vertically to protect the perimeter of any required floor as the construction progresses and are commonly referred to, therefore, as climbing screens. They typically comprise a climbing rail and a safety screen. The climbing rail is engaged, in use, by floor guides, which project outwardly from the edges of the floors. The floor guides allow translation of the climbing screen along the construction.

At any point when a climbing formwork or climbing screen is supported on a building at a desired level for concrete pouring or for work to occur, i.e. between vertical movements, the vertical load is generally taken by two or more floor guides at a single level, which floor guides may take the form of hook arrangements. Existing hook arrangements suffer from a number of drawbacks, including but not limited to potential obstruction of the vertical travel of the climbing formwork or climbing screen and a risk of injury to individuals seeking to manipulate the hooks of these hook arrangements.

The present invention arose in a bid to provide an improved hook arrangement retractable to eliminate any risk of obstruction and without the risk of injury to any individuals manipulating the hook.

According to the present invention in a first aspect, there is provided a hook arrangement that is mountable to a construction for selectively engaging and supporting a climbing screen or climbing formwork, the hook arrangement comprising: a hook, which is pivotally mounted so that it may move between a retracted position in which it may not engage the climbing screen or climbing formwork and a deployed position in which it may engage the climbing screen or climbing formwork; a biasing means, which is arranged to urge the hook into the deployed position; and a latching mechanism, which is arranged to be engaged automatically by pivotal movement of the hook from the deployed to the retracted position for maintaining the hook in the retracted position.

The latching mechanism preferably comprises a catch that is biased towards a first position in which it may engage the hook or an element rotatable with the hook. The catch may be biased towards the first position by gravity or by a biasing means.

The hook arrangement preferably comprises a cam surface, which is arranged to engage the catch by pivotal movement of the hook, for moving the catch from the first position. The hook itself may comprise the cam surface.

Further preferred features are presented in the dependent claims.

According to the present invention in a further aspect, there is provided a climbing screen system comprising a hook arrangement as defined above and a climbing screen.

According to the present invention in a further aspect, there is provided a climbing formwork system comprising a hook arrangement as defined above and a climbing formwork.

The climbing screen or climbing formwork may comprise a guide rail and one or more guide members, which are mountable to the construction for engaging the guide rail and restricting horizontal movement of the guide rail, wherein, in its retracted state, the hook is spaced from the guide rail so that vertical travel of the guide rail is uninhibited by the hook.

Non-limiting embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a portion of a climbing screen system according to the present invention, which comprises a climbing screen and a hook arrangement; Figure 2 shows a partial sectional side view of the hook arrangement shown in Figure 1; and Figure 3 shows an operational sequence of the hook arrangement of Figure 1, including a tool.

A hook arrangement that is mountable to a construction for selectively engaging and supporting a climbing screen or climbing formwork is shown in Figures Ito 3. The hook arrangement comprises a hook 1, which is pivotally mounted so that it may move between a retracted position (as shown in Figure 2) in which it may not engage the climbing screen or climbing formwork and a deployed position (as shown in Figure 1) in which it may engage the climbing screen or climbing formwork. A biasing means 2 is provided, which is arranged to urge the hook into the deployed position. The biasing means preferably comprises a coil spring as shown but may comprise any suitable alternative means. A latching mechanism 3 is provided, which is arranged to be engaged automatically by pivotal movement of the hook 1 from the deployed to the retracted position for maintaining the hook in the retracted position.

The latching mechanism preferably comprises a catch 4 that is biased towards a first position in which it may engage the hook, as seen in Figure 2. Whilst the catch engages the hook in the present arrangement, alternative arrangements will be possible in which an element is provided that is rotatable with the hook and is arranged to be engaged by the catch instead. In the present arrangement, the catch 4 is biased towards the first position by gravity. In alternative arrangements, a biasing means such as a spring may be implemented. The catch 4 preferably comprises a pin. The pin, as shown, may be retained within a closed slots, which limits the travel of the pin between the first position and a second position (shown in broken lines in Figure 2) in which the pin does not obstruct the pivotal movement of the hook. The slot is inclined to the horizontal so that the pin drops into the engagement position under the effect of gravity. In the present arrangement it is arranged at an angle of around 30 degrees although clearly this angle may be varied. In the present arrangement the axis of the pin is parallel to the axis of rotation of the hook, as may be seen in the figures. Numerous alternative catch arrangements will be readily appreciated by those skilled in the art and the present arrangement is not to be limited to a specific form of catch.

The latching mechanism further comprises a cam surface 6, which in the present arrangement is a surface of the hook itself, as shown. In alternative arrangements a separate cam could be provided to rotate with the hook, as will be appreciated by those skilled in the art, which separate cam could define the element rotatable with the hook mentioned above. The cam surface 6 is arranged to engage the catch by pivotal movement of the hook, for moving the catch 4 from the first position. Note the operation of the cam surface in Figure 3, wherein in the 4th image from the top the catch 4 has been raised by the cam surface 6 from the first position at the lower end of the slots.

The latching mechanism further comprises an engagement feature 7, which in the present arrangement comprises a step/recess immediately adjacent to the cam surface. Numerous suitable engagement features will be readily appreciated by those skilled in the art, which may take the form of steps, recesses, indentations or otherwise that are arranged on or adjacent to the cam surface. The biasing of the catch 4 towards the first position causes the catch 4 to engage the engagement feature 7 for maintaining the hook in the retracted position, as seen in Figure 2 and in the bottom image in Figure 3.

The hook pivots about a main axis 8. Pivotal movement of the hook is limited between predefined fully retracted and fully deployed positions by the provision of a slot 9, which defines a circular arc with the main axis 8 at its radial centre. A bar 10 is provided, which has its position fixed. The bar 10 extends parallel to the main axis 8 and is received within the slot 9. The bar 10 engages a first end of the slot 9 in the deployed position (as seen in Figure 1) and a second end of the slot in the retracted position (as seen in Figure 2).

The hook 1 is provided in a housing 11. The hook 1 is mounted within the housing 11 such that the hook lies at least partially within the housing in the retracted position (as seen in Figure 2) and at least partially outside the housing in the deployed position (as seen in Figure 3). In the present arrangement, as is preferable, the hook 1 lies substantially entirely within the housing 1 in the retracted position, as shown in Figure 2.

The housing 11 may be substantially box-like in construction with a suitable vertically extending opening provided in a front face 12 thereof for allowing suitable travel of the hook between the deployed and retracted positions. The front face may taper or curve outwards in the horizontal direction as it extends vertically up from the bottom, as clearly seen in the figures. It may further taper or curve outwards in the horizontal direction as it extends vertically down from the top, as again clearly seen in the figures. The outermost portion of the front face may extend substantially vertically between the upper and lower tapered portions of the front face, as shown.

The housing 11 is shown mounted to a support member 20 and supporting a climbing rail in Figure 3. The support member 20 is mounted to a floor of a construction (not shown). The housing is bolted to the support member 20 using bolts 14. Various alternative attachment arrangements will be possible. The hook arrangement may, for example be bolted directly to an outer vertical face of a floor or construction Cast anchors may be used. It may be alternatively be mounted to a floor of a construction directly or through alternative support elements.

It is highly preferable that the catch may be moved from the first position remotely, for remote deployment of the hook. It is further highly preferable that the hook may be remotely moved from the deployed position into the retracted position. One or more suitable openings in the housing may provide suitable access for such purposes.

The catch may be moved and the hook pivoted using a hand tool that is insertable through one or more suitable access openings and is appropriately shaped for the purpose. An exemplary suitable tool 15 is shown in Figure 3, which comprises a handle at a first end and a head, which comprises a pair of spaced prongs, at the opposed end. A curved shaft extends between the handle and the head. The tool may be substantially planar. As will be readily appreciated, numerous alternative tool configurations will be possible.

The provision of one or more access openings and the use of a suitable tool prevents the need for a user to place a hand anywhere near the workings of the hook arrangement, which vastly reduces the risk of injury. It is particularly preferable that the openings provided in the housing for tool access are too small or narrow for the insertion of a user's hand.

The curved nature of the shaft and the provision of the prongs allow for the engagement of the pin comprising the catch 4, for moving it upwards in its slots away from the first position. With the pin released the hook will deploy under the effect of the spring 2. The tool may be used for controlled deployment of the hook under the biasing force of the spring 2.

The hook 1 is preferably provided with one or more tool engagement features, which in the present arrangement are provided either side of the cam surface 6. A further pin 13 is provided that is fixed to the hook body in front of the cam surface 6 (wherein the front of the cam surface 6 contacts the catch 4 before the rear of the cam surface during retraction of the hook). The further pin 13 may be engaged with the tool, as shown in Figure 3. The axis of the further pin 13 preferably extends parallel to the main axis 8, as shown. To the rear of the cam surface, there are provided surface features in the form of protrusions 17, which may be engaged by the tool as again shown in Figure 3. The tool engagement features and the tool may clearly take alternative forms, as will be readily appreciated by those skilled in the art.

Figure 3 shows an operational sequence of the hook arrangement of Figures land 2 with the uppermost image showing the hook in the fully deployed state, the lowermost image showing the hook in the fully retracted position and the intervening images showing a series of intermediate positions between the fully deployed and fully retracted states. Also shown in Figure 3 is a line 16 that indicates an innermost edge of the climbing rail 30 of the climbing screen or climbing formwork in use. As clearly shown, with the hook in the fully retracted/latched state the hook lies spaced inwardly of the innermost edge of the climbing rail 30 in the horizontal direction. In the deployed state the hook, as seen in Figure 2, may engage a pin 31, or other suitable feature that is fixed to the climbing rail 30, for supporting a vertical load thereof, the hook 1 extending outwardly from the construction to which it is attached to overlap with the innermost edge of the climbing rail 30.

As is clear from Figure 3, when considering the retraction of the hook from the fully deployed state, with the end of the tool inserted through a suitable opening in the housing and engaged with the further pin 13, a downward force on the further pin 13 will retract the hook 1 against the biasing force of the spring 2. The curvature of the tool shaft allowing the latching of the hook 1 without undesirable unseating the latch 4.

The hook 1 may comprise a pair of spaced identical hook elements, wherein a gap is provided between the hooks through which gap the tool may be inserted for engaging the further pin 13.

In the present arrangement a hydraulic ram attachment means 40 is provided on an upper surface of the housing 11 for fixing a lower end of a hydraulic ram 50 thereto. The hydraulic ram 50 being arranged to lift the climbing rail 30 vertically along the construction. In alternative arrangements, as will be appreciated, the hydraulic ram attachment means 40 may be omitted.

Claims

Claims 1. A hook arrangement that is mountable to a construction for selectively engaging and supporting a climbing screen or climbing formwork, the hook arrangement comprising: a hook, which is pivotally mounted so that it may move between a retracted position in which it may not engage the climbing screen or climbing formwork and a deployed position in which it may engage the climbing screen or climbing formwork; a biasing means, which is arranged to urge the hook into the deployed position; and a latching mechanism, which is arranged to be engaged automatically by pivotal movement of the hook from the deployed to the retracted position for maintaining the hook in the retracted position.
2. A hook arrangement as claimed in Claim 1, wherein the latching mechanism comprises a catch that is biased towards a first position in which it may engage the hook or an element rotatable with the hook.
3. A hook arrangement as claimed in Claim 2, wherein the catch is biased towards the first position by gravity or by a biasing means.
4. A hook arrangement as claimed in Claim 2 or 3, wherein the catch comprises a pin.
5. A hook arrangement as claimed in Claim 4, wherein the pin is retained within a closed slot which limits the travel of the pin between the first position and a second position in which the pin does not obstruct the pivotal movement of the hook.
6. A hook arrangement as claimed in any of Claims 2 to 5, comprising a cam surface, which is arranged to engage the catch by pivotal movement of the hook, for moving the catch from the first position.
7. A hook arrangement as claimed in Claim 6, wherein an engagement feature, which may comprise a step, recess or indentation, is arranged on or adjacent to the cam surface, the biasing of the catch towards the first position causing the catch to engage the engagement feature for maintaining the hook in the retracted position.
8. A hook arrangement as claimed in any preceding claim further comprising a housing, wherein the hook is mounted within the housing, such that the hook lies at least partially within the housing in the retracted position and at least partially outside the housing in the deployed position.
9. A hook arrangement as claimed in Claim 8, wherein, in the retracted position, the hook lies substantially entirely within the housing.
10. A hook arrangement as claimed in Claim 8 or 9, when dependent on any of Claims 2 to 7, which is arranged such that the catch may be moved from the first position remotely.
11. A hook arrangement as claimed in Claim 10, wherein the housing comprises an access opening through which the catch may be accessed from outside the housing.
12. A hook arrangement as claimed in Claim 11 further comprising a hand tool adapted for insertion into the access opening for engaging the hook and/or the catch.
13. A climbing screen system comprising a hook arrangement as claimed in any preceding claim and a climbing screen.
14. A climbing formwork system comprising a hook arrangement as claimed in any of Claims 1 to 12 and a climbing formwork.
15. A climbing screen system as claimed in Claim 13, or a climbing formwork system as claimed in Claim 14, comprising a guide rail and one or more guide members, which are mountable to the construction for engaging the guide rail and restricting horizontal movement of the guide rail, wherein, in its retracted state, the hook is spaced from the guide rail so that vertical travel of the guide rail is uninhibited by the hook.
16. A hook arrangement as hereinbefore described with reference to the accompanying drawings.
17. A climbing screen system as hereinbefore described with reference to the accompanying drawings.
18. A climbing formwork system as hereinbefore described with reference to the accompanying drawings.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWSClaims 1. A hook arrangement that is mountable to a construction for selectively engaging and supporting a climbing screen or climbing formwork, the hook arrangement comprising: a hook, which is pivotally mounted within a housing and is moveable between a retracted position in which it lies at least partially within the housing and cannot engage the climbing screen or climbing formwork and a deployed position in which it lies at least partially outside the housing and can engage the climbing screen or climbing formwork; a biasing means, which is arranged to urge the hook into the deployed position; and a latching mechanism, which comprises a catch that is biased towards a first position in which it can engage the hook or an element rotatable with the hook, and is engageable automatically by pivotal movement of the hook from the deployed to the retracted position for maintaining the hook in the retracted position.2. A hook arrangement as claimed in Claim 2, wherein the catch is biased towards the first position by gravity or by a biasing means.3. A hook arrangement as claimed in Claim 2 or 3, wherein the catch comprises a pin.C\J 4. A hook arrangement as claimed in Claim 4, wherein the pin is retained within a closed slot which limits the travel of the pin between the first position and a second position in which the pin does not obstruct the pivotal movement of the hook.5. A hook arrangement as claimed in any of Claims 2 to 5, comprising a cam surface, which is arranged to engage the catch by pivotal movement of the hook, for moving the catch from the first position.6. A hook arrangement as claimed in Claim 6, wherein an engagement feature, which comprises a step, recess or indentation, is arranged on or adjacent to the cam surface, the biasing of the catch towards the first position causing the catch to engage the engagement feature for maintaining the hook in the retracted position.7. A hook arrangement as claimed in any preceding claim, wherein, in the retracted position, the hook lies substantially entirely within the housing.8. A hook arrangement as claimed in any preceding claim wherein the housing comprises an access opening through which the catch can be accessed from outside the housing for moving the catch from the first position remotely.9. A hook arrangement as claimed in Claim 8 further comprising a hand tool adapted for insertion into the access opening for engaging the hook and/or the catch.10. A climbing screen system comprising a hook arrangement as claimed in any preceding claim and a climbing screen.11. A climbing formwork system comprising a hook arrangement as claimed in any of Claims 1 to 9 and a climbing formwork.12. A climbing screen system as claimed in Claim 10, or a climbing formwork system as claimed in Claim 11, comprising a guide rail and one or more guide members, which are mountable to the construction for engaging the guide rail and restricting horizontal movement of the guide rail, wherein, in its retracted state, the hook is spaced from the guide rail so that vertical travel of the guide rail is uninhibited by the hook.13. A hook arrangement as hereinbefore described with reference to the accompanying drawings.14. A climbing screen system as hereinbefore described with reference to the accompanying drawings.15. A climbing formwork system as hereinbefore described with reference to the accompanying drawings.