AU2018232896B2

AU2018232896B2 - Remotely actuated guard rail clamp

Info

Publication number: AU2018232896B2
Application number: AU2018232896A
Authority: AU
Inventors: Karl David Emslie
Original assignee: Edge Protection New Zealand Ltd
Current assignee: Edge Protection New Zealand Ltd
Priority date: 2017-10-03
Filing date: 2018-09-18
Publication date: 2025-01-23
Anticipated expiration: 2038-09-18
Also published as: AU2018232896A1

Abstract

: In one aspect the invention provides a remotely actuated guard rail clamp 5 which includes a main body configured for attachment to a lifting member. A clamp jaw is pivotally connected to this main body, with the clamp jaw being arranged to pivot between an open configuration and a closed configuration. Also provided is a bias structure associated with the clamp jaw which applies a force directed to urge the jaw towards the closed configuration, as well as o an actuation structure associated with the jaw and being remotely operable to apply a force directed to urge the jaw towards the open configuration. 14 o~. C -9 CD I-. I-.. -n C -9 CD 0~1 0* o.~. C -9 CD C, 0

Description

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C, REMOTELY ACTUATEDGUARD RAILCLAMP

Field of the Invention

This invention relates to a remotely actuated guard rail clamp. In various embodiments the invention may be used to remotely release a guard rail engaged by the invention.

Background of the Invention

Edge protection systems are important tools used in the construction industry to prevent workers falling from dangerous heights. Edge protection systems can provide a temporary failsafe at the edges of a structure. This application can be contrasted with scaffolding systems which form temporary structural supports for a building under construction or renovation. Scaffolding components need to be strong and are generally over engineered to bear these structural loads.

Scaffolding systems are assembled from the ground up by connecting o together large numbers of individual components to eventually provide access to an elevated work area. Although scaffolding is time consuming to assemble and a relatively expensive form of safety system, it can be assembled without exposing workers to fall risks.

Edge protection systems are simpler and much quicker to deploy than scaffolding. However with these systems a user needs to expose themselves to fall risks when installing guard rails on a set of upright supports located at the edge of a structure. One approach used to mitigate these fall risks would be through the use of safety harnesses which tether a user to a fixed elevated point. However these harnesses incur additional costs and require specialised training to be undertaken by workers if the harnesses are to be used properly. Furthermore tethering a worker in this way also restricts their freedom of movement and can be perceived as an inconvenience.

It would be of advantage to have improvements in the field of edge protection and guard rail systems which improved on the current state of the art. In particular it would be of advantage to have an improved edge protection assembly system, apparatus or method which did not expose a user to the risk of a fall. Improvements over the prior art which did not require the use of harnesses by workers would also be of advantage.

Disclosure of the Invention

According to one aspect of the present invention there is provided a remotely actuated guard rail clamp which includes a main body configured for attachment to a lifting member, and o a clamp jaw pivotally connected to the main body, the clamp jaw being arranged to pivot between an open configuration and a closed configuration, and a bias structure associated with the clamp jaw which applies a force directed to urge the jaw towards the closed configuration, and an actuation structure associated with the jaw and being remotely operable to apply a force directed to urge the jaw towards the open configuration.

According to another aspect of the present invention there is provided a remotely actuated guard rail clamp substantially as described above wherein o the clamp jaw has a profile complimentary to the profile of a guard rail to be engaged.

According to a further aspect of the invention there is provided a method of assembling an edge protection system characterised by the steps of:

i. engaging a plurality of upright supports with the edge of a structure ii. engaging a guard rail with a remotely actuated guard rail clamp substantially as described above, iii. manoeuvring the guard rail into alignment with two upright supports, iv. remotely operating the actuation structure of the remotely actuated guard rail clamp to release the guard rail.

The present invention provides a remotely actuated guard rail clamp. This guard rail clamp can be used in the assembly of an edge protection system to manoeuvre a guard rail into contact with a pair of upright supports. The invention is arranged to allow a user to lift a guard rail up to these upright supports without exposing themselves to the risk of a fall, and then to remotely actuate the guard rail clamp to release the guard rail once engaged with the upright supports. The guard rail can then be securely fixed in place by the user who is protected from the risk of a fall by the presence of the guard rail.

The invention includes a main body which in use is engaged with a lifting member. The main body provides a mounting system or framework for the remaining components of the clamp. The engagement of the main body with a lifting member allows a user to grasp the far end of the lifting member and o lift a guard rail engaged by the clamp.

Reference throughout the specification be made to the invention's main body being engaged with a lifting member formed by a pole, post, rod or any equivalent element which a user can employ to lift and manoeuvre a guard rail engaged by the clamp. Preferably the main body of the clamp may be engaged with a strong lightweight aluminium pole in preferred embodiments, although those skilled in the art will appreciate that alternative approaches are also within the scope of the invention.

o In a preferred embodiment the main body may define a socket structure capable of receiving and partially enclosing a guard rail. Preferably this socket structure may have a profile complimentary to the cross-section profile of the guard rail to be manoeuvred by the invention. This socket can receive a guard rail yet still allow it to be freely removed from the socket.

The invention includes a clamp jaw pivotally connected to the main body. In a preferred embodiment the clamp jaw may define a structure with two opposed ends, one of these ends being defined as the linked end of the jaw which is pivotally engaged with the main body. The opposite end of the jaw can be defined as its free end which is afforded the greatest freedom of movement.

This clamp jaw may pivot to and from an open configuration and a closed configuration. In its closed configuration the clamp jaw can be pivoted to at least partially surround or enclose a guard rail located in proximity to the clamp. In its open configuration the clamp jaw will be located in a position which does not surround the guard rail or restrict the movement of the guard rail away from the clamp. In embodiments where the main body defines a socket structure, this combination and the positioning of the clamp jaw in the closed configuration may enclose an arc of at least 180 degrees of the cross section profile of the guard rail, locking the guard rail inside the socket and jaw.

In a preferred embodiment the clamp jaw may be pivotally connected to the main body through the provision of an axle. One end of the clamp jaw may be linked to this axle, leaving the opposite end of the jaw free to move and o pivot about the rotational axis of the axle.

The clamp jaw provided by the invention may preferably be formed with a profile complimentary to the profile of a guard rail to be manoeuvred. For example in embodiments where tubular guard rails are to be manoeuvred the clamp jaw may form a complimentary 'C' shaped structure which is able to make contact with the majority of the exterior surface profile of a tubular guard rail.

The invention also incorporates a biasing structure engaged with the clamp o jaw, this structure being arranged to continuously apply a force to the clamp jaw which urges it towards its close configuration. For example in one preferred embodiment a spring may be provided as the biasing structure to ensure that the default configuration of the clamp jaw is it's closed position. This biasing structure also locks a guard rail inside a clamp jaw, preventing it from falling out of the clamp during manoeuvring operations.

In a further preferred embodiment where an axle is used to pivotally mount the jaw to the main body a biasing structure may be provided by a spring which is threaded on or otherwise located by the axle. This spring can be connected to a further static portion of the main body and also contact the opposite side of the clamp jaw to that which is engaged with a guard rail. In such embodiments this spring may be tensioned by its fixed engagement with a static portion of the main body as the opposite or back side of the clamp jaw is moved towards the jaw's open configuration.

For example in some embodiments this kind of spring may be formed with two forward extending legs, each defining a circular socket for the axle and being joined at 90 degrees to a common backstay element. The free ends of these legs can be engaged with the main body while the circular sockets are threaded over the axle and the backstay is used to be against the back side of the clamp jaw.

The guard rail clamp provided by the invention also includes an actuation structure associated with the clamp jaw. This actuation structure can allow a user of the invention to apply a force which urges the clamp jaw into its open configuration when the user is located remote from the clamp.

In a preferred embodiment the invention's actuation structure may be engaged with the free end of the jaw, allowing it to apply a force to the portion of the jaw with the greatest freedom of movement.

In a preferred embodiment this actuation structure may be provided by or incorporate a flexible length of cord, rope, or any other equivalent flexible elastic length of material which can be pulled by user to apply a force to the jaw clamp.

o In a further preferred embodiment the invention's actuation structure may also include an offset linkage engaged at one end with the free end of the clamp jaw and at its opposite end with a length of cord. This offset linkage can be used to translate the force applied by user pulling the cord into a force which pivots the free end of the clamp jaw away from a guard rail engaged by the clamp.

In some embodiments the offset linkage may also form or define a locking slot which cooperates with a locking nut projecting from the main body. This locking slot and nut combination can be used to retain the clamp jaw in the closed configuration by the sidewalls of the slot trapping the nut in a stationary position which counteracts external forces capable of acting to open the clamp jaw. A user operating the actuation structure can move the locking nut out to an alternative position within the locking slot which does not impede opening of the clamp jaw.

Reference throughout the specification also in general be made to an actuation structure being formed by a flexible length of cord or a combination of this cord with an offset linkage. However those skilled in the art will appreciate that either or both the cord and offset linkage may potentially be replaced by electrically driven motors or similar components which may be commanded remotely to apply an opening force to the clamp jaw.

In a preferred embodiment the main body may also define or be connected to a lateral stabilisation structure. This stabilisation structure may provide a member which extends in line or parallel with the axis of rotation of the o clamp jaw pivot. This stabilisation structure can therefore provide a bracing surface which extends along the longitudinal length of a guard rail clamped by the invention, thereby impeding tipping or pivoting movements in the guard rail when manoeuvred.

The present invention therefore facilitates a method of assembling an edge protection system which does not expose its users to fall risks, nor does it require them to wear safety harnesses. A user of the invention assembling an edge protection system can firstly engage several upright supports with the edge of a structure, and then engage a guard rail with the remotely o actuated guard rail clamp provided by the invention. While still located on the ground - or other lower safe working site - the user can then manoeuvre the guard rail into alignment with two of the upright supports. The invention then allows this worker to remotely operate the actuation structure of the invention to release the guard rail on to the upright supports. Work can continue manoeuvring and placing the guard rails of the edge protection system using invention, with the user only needing to work at height to fix the guard rails to the upright supports once the edge of the structure is protected by the guard rails.

Brief description of the drawings

Additional and further aspects of the present invention will be apparent to the reader from the following description of embodiments, given in by way of example only, with reference to the accompanying drawings in which:

* Figure la, lb show perspective views of a remotely actuated guard rail clamp as provided in accordance with one embodiment of the invention, * Figure 2 shows a front view of the clamp of figure 1, * Figure 3 shows a cross section view of the clamp of figures 1 and 2, * Figure 4 shows the clamp of figures 1 to 3 in an open configuration, and * Figure 5 shows the clamp of figures 1 to 4 in a closed configuration, and o * Figures 6a, 6b and 6c show a number of side cross-section views of a clamp formed in accordance with a further embodiment of the invention.

Further aspects of the invention will become apparent from the following description of the invention which is given by way of example only of particular embodiments.

Best modes for carrying out the invention

o Figures 1 to 5 show a number of views of a remotely actuated guard rail clamp as provided in accordance with one embodiment of the invention.

The clamp 1 is formed from a main body 2 which has an end 3 arranged to slot into a lifting member pole (not shown). The opposite end of the main body also defines a socket 4 which is arranged to receive and locate one side of a tubular guard rail. As can be seen from these figures the socket has a curved semi-circular profile arranged to complement the exterior surface of a tubular guard rail.

A lateral stabilisation structure 5 is also formed at the far end of the socket to prevent rocking or pivoting of a guard rail when engaged with the clamp 1.

An axle 6 provides a pivoting linkage which engages a clamp jaw 7 to the portion of the main body 2 which forms a part of the socket 4. The linked end of the clamp jaw is threaded on to this axle, leaving the opposite free end of the clamp jaw free to move. This freedom of movement allows the clamp jaw to pivot between the open configuration shown with respect to figure 4 and the closed configuration shown with respect to figure 5. The jaw clamp 7 has a curved "C" shaped profile which complements that of the exterior surface of a tubular guard rail.

The clamp 1 also incorporates a biasing means, implemented in this embodiment by a spring clip (no shown). This clip is engaged between the clamp jaw 7 and socket 4 of the main body. Movement of the clamp jaw towards its open configuration will load the clip, causing it to apply an o opposing force which urges the clamp jaw back to its closed configuration.

These figures also show the provision of part of a remote actuation structure, formed in this embodiment with an offset linkage 8 engaged at one end 8a with the free end of the clamp jaw, and at its opposite end 8b with a length of cord (not shown). The combination of the offset linkage and cord forms the remote actuation structure, allowing a user to open the clamp by pulling on the cord attached to the offset linkage. This pulling force will the urge the clamp jaw open, allowing a guard rail to be released from the jaw and socket 6.

As shown by figure 4 the offset linkage is pulled downwards pulling the free end of the clamp jaw away from the socket, leaving one side of the socket open and the guard rail free to exit the clamp. Once the offset linkage is released the spring clip pulls the jaw clamp into the closed configuration shown by figure 5. The combination of the clamp jaw placed in the closed configuration with the socket formed at the end of the main body traps a guard rail in place inside the clamp.

As can also be seen from figures 1 through 3 the clamp 1 can be constructed from a number of cut or pressed sheets of material connected together. The end of the main body engaged with the lifting member pole can be formed from a series of components orientated and connected at right angles. Two of these components extend upwards to form the socket and are linked together by a further plate forming the lateral stabilisation structure. The clamp jaw is formed in this embodiment by a pair of plates which extend towards and are threaded on to the axle, these plates being separated from one another by further pair of washer plates.

Figures 6a, 6b and 6c show a number of side cross-section views of a clamp formed in accordance with a further embodiment of the invention.

In the embodiment shown the offset linkage of the clamp incorporates a locking slot 9 which cooperates with a locking nut 10 projecting from the body 2. When the clamp jaw is closed the locking nut is located in the lower region of the locking slot. In this configuration the locking nut engages with the sidewalls of the locking slot to prevent inadvertent opening of the clamp o jaw. The spring 11 shown with respect to figure 6a also acts to ensure that the locking nut stays seated inside the lower region of the locking slot. Conversely when a downward force is applied by user to the offset projection which overcomes the pull of the spring 11 this moves the locking nut out of the lower region of the locking slot and frees the clamp jaw to move into its open configuration.

In the preceding description and the following claims the word "comprise" or equivalent variations thereof is used in an inclusive sense to specify the presence of the stated feature or features. This term does not preclude the o presence or addition of further features in various embodiments.

It is to be understood that the present invention is not limited to the embodiments described herein and further and additional embodiments within the spirit and scope of the invention will be apparent to the skilled reader from the examples illustrated with reference to the drawings. In particular, the invention may reside in any combination of features described herein, or may reside in alternative embodiments or combinations of these features with known equivalents to given features. Modifications and variations of the example embodiments of the invention discussed above will be apparent to those skilled in the art and may be made without departure of the scope of the invention as defined in the appended claims.

Claims

What we claim is:

1. A remotely actuated guard rail lifting clamp for lifting guardrails from a remote location which includes a main body engaged with one end of a lifting member pole, and a clamp jaw pivotally connected to the main body, the clamp jaw being arranged to pivot between an open configuration and a closed configuration, and a bias structure associated with the clamp jaw which applies a force o directed to urge the jaw towards the closed configuration, and a stabilisation structure projecting from the clamp jaw parallel with the axis of rotation of the clamp jaw pivot and defining a bracing surface which extends from the jaw parallel to a lifted guard rail, and an actuation structure associated with the jaw and being remotely operable to apply a force directed to urge the jaw towards the open configuration, the actuation structure including a flexible length of material engaged at one end to the clamp jaw with an opposite end extending to the opposite end of the lifting pole and being pulled by a user to apply a force to the clamp jaw.

2. A remotely actuated guard rail clamp as claimed in claim 2 wherein the main body is engaged with a lifting member formed by an aluminium pole.

3. A remotely actuated guard rail clamp as claimed in claims 1 or 2 wherein the main body defines a socket structure with a profile complimentary to the cross-section profile of the guard rail, where the socket structure in combination with the clamp jaw located in the closed configuration encloses an arc of at least 180 degrees of the cross section profile of the guard rail.

4. A remotely actuated guard rail clamp as claimed in any one of claims 1 to 3 wherein the clamp jaw positioned in the closed configuration at least partially surrounds a guard rail located in proximity to the clamp and the clamp jaw positioned in the open configuration is located in a position which does not prevent the movement of the guard rail away from the clamp.

5. A remotely actuated guard rail clamp as claimed in any one of claims 1 to 4 which includes an axle arranged to pivotally connect the clamp jaw to the main body to the clamp jaw, where one end of the clamp jaw is connected to the axle leaving the opposite end of the jaw free to move and pivot about the rotational axis of the axle.

6. A remotely actuated guard rail clamp as claimed in any one of claims 1 to 5 wherein the clamp jaw has a profile complimentary to the profile o of a guard rail to be engaged by the guard rail clamp.

7. A remotely actuated guard rail clamp as claimed in claim 6 wherein the clamp jaw forms a complimentary 'C' shaped structure arranged to contact the exterior surface of a tubular guard rail.

8. A remotely actuated guard rail clamp as claimed in claim 7 wherein the biasing structure is formed by a spring threaded on an axle arranged to pivotally connect the clamp jaw to the main body to the clamp jaw.

o 9. A remotely actuated guard rail clamp as claimed in claim 8 wherein the spring is connected to the main body and the opposite side of the clamp jaw to that which is be engaged with a guard rail.

10. A remotely actuated guard rail clamp as claimed in any one of claims 1 to 9 wherein the actuation structure allows a user to apply a force which urges the clamp jaw into its open configuration when the user is located remote from the clamp.

11. A remotely actuated guard rail clamp as claimed in any one of claims 1 to 10 wherein the clamp jaw defines a structure with two opposed ends, being the linked end of the jaw which is pivotally engaged with the main body and the opposite free end of the jaw.

12. A remotely actuated guard rail clamp as claimed in claim 11 wherein the actuation structure is engaged with the free end of the jaw.

13. A remotely actuated guard rail clamp as claimed in any one of claims 11 or 12 wherein the actuation structure includes an offset linkage engaged at one end with the free end of the clamp jaw and at its opposite end with a length of cord.

14. A remotely actuated guard rail clamp as claimed in claim 13 wherein the offset linkage translates a force applied by user pulling the cord into a force which pivots the free end of the clamp jaw away from a guard rail engaged by the clamp.

15. A remotely actuated guard rail clamp as claimed in claim 14 wherein the offset linkage defines a locking slot which cooperates with a locking nut projecting from the main body.

16. A method of assembling an edge protection system using a remotely actuated guard rail clamp as claimed in claim 1 characterised by the steps of:

i. engaging a plurality of upright supports with the edge of a o structure ii. engaging a guard rail with the remotely actuated guard rail clamp, iii. manoeuvring the guard rail into alignment with two upright supports, iv. remotely operating the actuation structure of the remotely actuated guard rail clamp to release the guard rail.