GB2425805A

GB2425805A - Sliding clamping device

Info

Publication number: GB2425805A
Application number: GB0509325A
Authority: GB
Inventors: Nigel Hollis
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-05-07
Filing date: 2005-05-07
Publication date: 2006-11-08
Also published as: GB0509325D0

Abstract

A clamping device comprising two frame members 201 202, wherein each frame has an associated clamping face. The frame members are arranged in a relatively slidable relationship, preferably with the movement indexed. The device comprises handle means 208 209 such that when in use hand pressure on the handle means will effect relative movement of the frame members so as to move the clamping faces towards each other. There is also a releasable locking means 210 associated with the frame members which use acts to maintain the relative positions of the clamping faces when the hand pressure is released. The device can preferably be operated with one hand. A spring is provided so when the locking mechanism is released the two clamping faces move apart. The clamp is designed to attach ladders on roof racks.

Description

IMPROVED LADDER CLAMP

Field of the Invention

The present invention relates generally to the attaching of items to vehicles and more particularly to the attachment of ladders to the exterior of a vehicle.

Background to the Invention

Workmen often need to travel on a daily basis to new places where work sites are located. It is necessary for them to carry all of the equipment and materials they would need to perform their jobs. In most of the manual trades vans are employed, inside of which are stored or at least transported the various tools and materials needed to perform the required work.

Problems arise when a piece of material or equipment is of a size which cannot be easily fitted into a workman's van. In some instances this may be because the material or piece of equipment is not needed on all job sites and so can be specially delivered to such job sites as required and therefore vans are not designed to generally accommodate these particular items. However, this is not always the case and some almost universally required equipment often is of a size to large to fit inside a van. The most obvious example of this is a set of ladders, these generally being of a length almost equal or sometimes in excess of the complete length of the van even when in a storage configuration or folded.

Ladders are an essential item for many activities and are absolutely essential for trades which involve working upon the exterior of buildings for instance glazers and roofers, It is therefore essential that means exist to allow the transportation of ladders together with the rest of a workman's tools to a place of work.

A solution to this problem is to securely attach the ladder to the exterior of the van by a one of a number of known prior art means. There exist a number P1363 as filed such means for securing ladders to the exterior of a van and these will be discussed in the necessary detail together with an indication of the problems

associated with each of these prior art solutions.

s A van is generally modified by the addition of a suitable roof or side rack.

Such a rack generally consists of one or more bars which are raised up off the surface of the vehicle but also securely attached to the vehicle. Ladders may then be attached to this rack and so to the vehicle by securing the ladder at or about the raised bars. Securing of the ladders can be achieved using a number of different means.

For instance the ladders may be simply tied onto the roof rack using ropes or alternatively and more preferably bungle ropes, these being elasticated ropes which can be wrapped around the ladder rack so securing the ladder in place. In general however, this method of securing ladders to vehicles is not considered safe, even when using multiple ropes. In any case if multiple ropes are used to secure a set of ladders to a vehicle the amount of work involved in tying such a ladder to a vehicle is immense and therefore highly inefficient both when attaching the ladder(s) to the vehicle and when removing the ladders from the vehicle.

An alternative to using a rope or elasticated bungie rope is to use one or more chains. Chains have greater structural strength than a rope and therefore by attaching a ladder to a vehicle using chains and most normally some form of padlock or locking means it is expected that the ladder would be securely attached to the rack and vehicle. Given however the way in which chains are constructed, that being from a number of links, the securing of a ladder to a rack using a chain allows the ladder a great deal of movement. Although when stationery this may not be of concern to the occupants of the vehicle, when the vehicle is travelling at speed any movement of the ladders would be seen as most undesirable, also the unpredictable position of the ladder on the vehicle whilst in transit would be a hazard to other road users. Finally, given the freedom

P1 363.Specification 012505

of the ladders to move about the rack in general, in some instances of extreme deceleration, for instance, in order to avoid an accident or collision, the combined momentum of the ladder and chain may be expected to severally damage the roof rack and in some instances when the combined weight/momentum of the ladders attached to rack is sufficient cause the ladders and rack to become detached from the rack, again causing severe road safety issues for other road users.

At the present time a popular way of securing ladders to a vehicle is to employ a rack which has previously been described and a hooked threaded bar with a second cross bar member as shown in figure 1 herein.

With reference to figure 1 herein there is shown a prior art threaded jbar attachment means suitable for attaching a ladder to a vehicle which is fitted with a roof rack. The threaded j-bar 101 comprises two regions, a first region 103 which is substantially straight and a second region 104 which is curved to form a hook and is permanently attached to the straight region 103.

The straight region 103 further comprises a helical thread 105 which runs down the longitudinal axis of the straight region 103. This helical thread 105 begins at the very end of the straight region 103 such that a suitably adapted piece may be fitted onto the straight region 103 of the j-bar 101 and moved up and down the straight region upon the helical thread 105.

The hook region 104 of the j-bar 101, is configured such that the bar of the previously discussed roof/side rack sits inside the hollow 106 of the hook 103 interior thereby preventing further movement of the j-bar 101 in a direction substantially in parallel with the straight region 103 of the j-bar 101. Obviously at this point the j-bar is still free to move in a number of other directions but in practice the j-bar 101 would normally be held in this position such that the interior of the hook region 106 is in direct physical contact with the underside of the rack

P1 363.Specification.01 2505

visa contact between other regions of the attachment means 100 and the roof rack and items being attached.

Turning now to the cross bar piece 102, this cross bar piece 102 comprises two peripheral regions 107 and 108 which extend out radially from a central piece 109. At the center of this central piece there is formed an aperture with a suitable internal helical threading for interaction with the helical threading of the helical region 105 of the straight portion 103 of the j-bar 101.

This prior art attachment means 100 may therefore be used as follows, imaging a vehicle with a roof rack comprising two bars situated I.5mtrs apart on the roof of the van, a ladder is placed upon these two bars of the roof rack such that it is stable and balanced upon the vehicle when unsupported by other means. A first threaded j-bar 101 is then taken and placed through the ladder and also positioned underneath one of the bars of the roof rack. It is positioned such that the straight region 103 of the j-bar 101 is higher than the level of the ladder when situated upon the rack. Further the j-bar 101 is positioned such that the interior of the hook region 106 substantially abuts the underside of the rack.

Now the cross bar piece 102 and specifically the aperture 110 of the central portion 109 of the cross bar 102 is positioned such that it abuts the top of the straight region 103. The cross bar 102 is now rotated in a direction such that the interior helical threads of the aperture are accepted by the helical thread 105 of the straight region 103 and with successive revolutions of the cross bar 102 about the j-bar 101, the cross bar piece descends upon the helical thread 105 towards the hook region 104 of the j-bar.

In this way therefore the cross bar piece 102 descends down the straight region 103 of the j-bar 101 and eventually will come into contact with a portion of the ladder.

P1 363.Specification.01 2505

The cross bar piece 102 is tightened such that direct physical contact is made between the cross bar piece 102 and the ladder and also between the interior of the hook region 106 and the underside of the rack. At the end of this tightening, the ladder should be securely fixed to the rack at this position.

Additional threaded j-bars may be now used to secure the ladder to the second bar of the rack or alternatively or in addition further threaded jbars may be used to attach a different region of the ladder to the same cross bar so more securely attaching the ladder to the rack and the vehicle.

Additional sets of ladders may be attached to a vehicle using the same threaded j-bars, in this instance it will be appreciated that the number of revolutions of the cross bar piece necessary to bring it into contact with the uppermost member of a set of stacked ladders.

The threaded j-bar attachment means as previously discussed and described is at the present time one of the most popular means of attaching a set of ladders to a van with a roof rack.

However, substantial problems relating to the use of such attachments means exist, the most common of those being the length of time necessary to perform the required number of revolutions so as to bring the cross bar to securely contact the ladder and attach it to the rack. There are no shortcuts in this process as any interruptions or other adjustments of the helical thread would make a j-bar unsuitable for purpose.

The securing of ladders to a van at a depot and the taking of ladders of a van at work site is a long process and valuable time is lost because of the time taken to run the cross bar members up and down the length of a jbar at the beginning and end of each working day and when ever the ladders will be unattended for instance during lunch.

P1363 Specification.O1 2505

To summarize, this problem known in respect of existing j-bar attachment means and also the less well used means previously described involving ropes or chains, is the time involved in securing ladders to a vehicle such that the ladder is unable to move to any dangerous degree involves a significant investment of time on the part of the technician who performs this task.

Additional problems exist regarding the securing of ladders to vans for security purposes, at the present time ladders are generally padlocked to vans in addition to the normal j-bar attachments means.

Summary of the Invention

Seeing these problems associated with the prior art therefore the inventors have arrived at a novel and inventive solution to the problems of attaching ladders to vans.

The preferred embodiment of the invention involves a clamping device which comprises two frame members and wherein each of these frame members has an associated clamping face. The frame members are arranged in a relatively moveable relationship to each other and the two frame members are in an opposed but spaced apart relationship. The device is further characterised in that handle means are provided which have been configured such that when the device is in use and pressure is applied to the handle means, this will effect the relative movement to the frame members so as to move the two clamping faces towards each other. The invention further comprises a releaseable locking means associated with the frame members which in use acts to maintain the relative positions of the clamping faces when hand pressure is released.

The inventors have therefore provided a means to quickly bring together the two clamping faces device so securing a ladder or other piece of equipment to a rack, and then the clamping device may be further activated via the handle means so as to bring together the clamping faces further so completely securing the ladder to the rack.

P1 363.Specification.01 2505

According to other aspects of the present invention a clamping device is provided as described which is operable using one hand.

Also the clamping device maybe modified such that the frame members are in a relatively slideable relationship.

Preferably the clamping device maybe modified such that spring means move the clamping faces apart when the locking means is released.

Preferably the clamping device may operate such that the clamping action is indexed.

Most preferably the clamping device may operate such that the locking of the locking means is achieved by frictional engagement.

Most preferably the clamping device may comprise handle means formed integrally with the second frame member.

According to a further aspect of the present invention there is provided a clamping device which includes first and second members slideably moveable relative to one another between a clamping position in which an object is clamped and a release position in which said object is released and means for anchoring the relative movement of the first and second device members when in the clamping position.

Brief Description of the Drawings

For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which:

P1 363.Specification.0 12505

Figure 1 herein shows a prior art threaded j-bar clamping device.

Figure 2 herein shows a ladder clamping device according to a first embodiment of the present invention.

Figure 3 herein shows a ladder clamping device comprising a rack holding mechanism according to a second specific embodiment of the present invention herein.

Figure 4 herein shows a third specific embodiment of a ladder clamping device according to the present invention.

Figure 5 herein shows a ladder clamping device according to a fourth specific embodiment of the present invention.

Figure 6 herein shows a ladder clamping device according to a fifth specific embodiment of the present invention.

Figure 7 herein shows a safety locking means considered for use with a ladder clamping device according to the present invention.

Figure 8 herein shows a lockable safety device suitable for use with an embodiment of the present ladder clamping invention as described herein.

Detailed Description

There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to

unnecessarily obscure the description.

P1 363.Specification.01 2505

With reference to Figure 2 herein there is shown a ladder clamping device according to a first specific embodiment of the present invention. This ladder clamping device 200 comprises a first frame member 201 and a second frame s member 202. The first frame member 201 is in the form of a single metal bar, this bar is curved at an end so as to form a hook portion 203. The other portion of the first member 201 is a straight region 204.

The first frame member 201 may be made from a wide range of materials.

The inventor in particular prefer weather hardy steel alloys. In use, the first frame member 201 will be exposed to a significant amount of physical strain and therefore it needs to have sufficient structural rigidity and strength to perform its function when under such strain. Additionally, the working life of the first frame member will be almost exclusively outdoors and it is therefore again essential that the first frame member 201 is hardy in such conditions and not liable to rust. As an alternative to a non-rusting metal alloy, a cheaper grade of metal may also be used but, in this instance, protected by a film of plastic or other suitable material.

The second frame member 202 according to this specific embodiment of the present invention comprises a cross portion 205 and an upright piece 206.

The second frame member 202 is configured such that via an aperture in the cross piece 205 the second frame member 202 may be mounted upon the first frame member 201. The second frame member 202 is configured such that the aperture 207 is within the upright piece 206 and so when the second frame member 202 is mounted upon said first frame member 201 the straight portion of said first frame member 201 is located within the upright piece 206.

The upright piece 206 further comprises a first and second handle 208 and 209 respectively. The first handle 208 is fixed to the upright section 206 of the second piece 202 at a substantially 90 angle to an exterior surface of the upright piece 206. According to this specific embodiment of the present invention the P1 363.SpecificatjonOi 2505 first handle member 208 is not able to move relative to any of the other components of the second frame member.

The second handle member 209 is configured so as to contact and interact with the straight portion 204 of the first frame member 201. According to this first specific embodiment of the present invention the second frame member and particularly the second trigger member 209 are configured so as to function in a similar fashion to a sealant gun. That is by operation of the trigger 209, the second frame member 202 moves in a single direction down the straight portion io 204 of the first frame member 201 towards the hook region 203. The second frame member 202 moves over an interval which each full depression of the trigger. With each movement of the second trigger 209 the second frame member 202 moves in a controlled manner from one end of this interval of movement to the other. Removal of pressure from the trigger at any point during the movement, immediately causes the second frame member to stop and due to braking means 210 to be fixed at the position.

According to this first specific embodiment of the present invention the brake mechanism 210 is in the form of a piece of material with an aperture 211 formed within in, this aperture being of a size such that the first member 201 and specifically the substantially straight portion 204 of the first frame member may be located within this aperture 211.

The braking mechanism 210 further comprises an end piece 212 and a spring or biasing means 213 located between the end piece 212 and the braking means 210. The configuration of the end piece 212 and braking means 210, the biasing means 213 pushes the braking means 210 such that a substantial portion periphery of the aperture is in contact with the first frame member 201. In this way, due to the frictional contacts between the braking means 210 and the first frame member 201 all of the components connected to the braking means 210 are unable to move relative to the first frame member 201. The configuration of

P1363 Specification.01 2505

the components which go into making the braking mechanism means the brake is constitutively active, i.e., continually on.

To disengage the brake, the end piece 212 moves down relative to the locking means 210 and in this way force is transferred into the biasing means 213. This force in the biasing means 213 causes the position of the locking means 210 to change relative to the first frame member 201.

The locking means 210 takes a perpendicular orientation relative to the first frame member and so itself and all the other components attached thereto are able to move freely about the first frame member 201. Most normally force onto the end piece 212 comes from the trigger 210 and if such force continues to be exerted this will mean that the locking means continues to be disengaged and also continuing force is absorbed by the biasing means. This force is then dissipated pushing the substantially perpendicular locking means 210 away from the end piece 212 until such time as the floor is contained within the biasing means 213 is no longer sufficient to cause the locking means 210 to become substantially perpendicular relative to the first frame member at which time the locking means will reengage as itself and the other components attached thereto will become fixed relative to the first frame member again.

Two ways therefore exist for deactivating the locking means 210 and so moving the second frame member 202 about the first frame member 201. The first of these has already been explained wherein the second trigger 209 when depressed or brought closer to the first trigger 208 causes force to be exerted upon the end piece which is also capable of movement relative to the locking means 210 and the first frame member 201, this force causing the end piece 212 to move relative to the first frame member 201 and the locking means 210 causes a concomitant increase in the tension of the biasing means 213, the biasing means seeks to transmit this force to the locking means 210.

P1 363.Specification.O1 2505

The locking means moves from a first position wherein a substantial portion of the inner surface of the aperture 211 is in contact with the first frame member changes to one in which the locking means 210 is in a substantially perpendicular orientation relative to the first frame member 201. Additional force from the biasing means continues to ensure that the locking means remains disengaged from the first frame member and also is converted into movement of the locking means 210 away from the end piece 212 until all tension from the biasing means is expended and the locking means 212 is once again able to engage along a substantial portion of the inner aperture 211 with the first frame member 201.

The second mode of operation for the locking means 210, involves the manual operation of the locking means 210 from its normal constitutively active position wherein a substantial portion of the inner surface of the aperture 211 is in contact with the first frame member 201 to a substantially perpendicular orientation of the locking means 210 relative to the first frame member 201 such that no portion of the locking means 210 is in direct physical contact with the first frame member 201. This direct physical manipulation of the locking means will of course affect the tension in the biasing means to 13 but such tension as may be created in the biasing means would not impede the adjustment of the locking means by a skilled user.

Once the locking means 210 has been manually disengaged by the user of the device the second frame member 202 is now free to move relative to the first frame member 201. In this mode of operation the movement of the second frame member 202 is not over a fixed interval relative to the first frame member 201 as is the case when using the second trigger 209 movement mechanism.

Therefore, large movements of the first and second frame members can be made relative to each other so as to adjust the first and second frame members to the particular environment in which they are found.

As an example of how such functionality may be useful, if one imagines that the length of a substantively straight portion 204 of the first frame member 201 is

P1 363.Specification 012505

of a size X and the interval of movement the second frame member 202 moves upon the first frame member is a small fraction of X. Therefore, starting at a first end of the first frame member 201 with the second frame member 202, a great many operations of the trigger would be required to move the second frame member along the length of the first frame member 201. By using the second mode of operation, however, i.e. manually disengaging the locking means 210 the second frame member 202 can be brought quickly into an appropriate position relative to the first frame member 201 and only once in such a good position may final adjustments be made using the trigger mechanism.

According to this first specific embodiment of the present invention all of the components previously described herein according to this specific embodiment of the present invention form a single piece of apparatus meaning the first and second frame members although capable of movement relative to each other so long as the locking means 210 is disengaged are not capable of separation.

There will now be described a number of additional features which the inventors consider add to the existing functionality of their invention.

Firstly, to aid in the operation of the device, means are provided which allow the selective connection of the first frame member to the bar of a roof rack or side rack. In a first embodiment of this there is provided a bar gripping means which allows the selective connection of the first frame member to a cross bar.

With reference to Figure 3 herein there is shown a first frame member 301 which is much as previously described in relation to the first specific embodiment of the present invention herein. This first frame member further comprises a bar gripping means 302. According to this specific embodiment of the present invention this bar gripping means 302 is configured such that it comprises a first portion 303 and a second portion 304. The first portion 303 is configured so as to fit over the first frame member 201 and is capable of movement along the entire length of said first frame member 301. The bar gripping means 302 is in the form P1 363.Specfication 012505 of a piece of material configured at end 303 to conform with the physical cross section of the first frame member 301.

The second component of the bar gripping means 302 is a recess suitable for accepting the cross bar of a roof rack. According to this specific embodiment of the present invention this second portion 304 is configured such that the inferior surfaces of the recess 304 are curved outwards, further at least this portion of the bar gripping means 302 is comprised of a material with a suitable degree of elasticity. Before engagement of the bar gripping means 302 with the cost bar. The interior dimension of aperture 304 is of a size smaller than the dimension of the cross bar member.

The aperture 304 and the cross bar gripping means may be positioned upon the cross bar member, however, via the application of force causing the movement of exterior portions of the aperture 304 so as to accommodate the cross bar member. Similarly, the cross bar gripping means may be disengaged from the cross bar member by the application of force. According to the specific embodiment of the present invention such cross bar gripping means allows the easier interaction of the first frame member 301 with the cross bar as the first frame member 301 is affixed to the cross bar and does not therefore need to be held in place whilst adjustments are made either to the second frame member associated with the first frame member 301 or alternatively to the items which are to be secured to the vehicle using the ladder clamping device.

An alternative form of cross bar gripping device is shown in Fig. 4 herein, according to this specific embodiment of the present invention the first frame member 401 comprises a disk of material. This disk of material is configured so as to sit underneath the cross bar member. From this disk of material 401 a horizontal bar or pole 402 projects substantially perpendicular to the disk 401.

The second frame member may be fitted and so adjusted by bringing the second frame member into proximity with the first frame member 401.

P1363 Specification.O1 2505

The inventors consider a disk of materials a viable alternative to the use of a book and also that such a frame member has a number of technical advantages over hooks. Firstly, when the device is disengaged from the ladder, the first frame member 401 in the form of a disk is capable of sitting at rest upon the roof of a vehicle and being entirely self supporting in this fashion. In such a situation the upright member 402 would still project upwards from the first frame member 401 and allow the accurate placing of this member relative to the roof rack and such components as to be carried.

A disk of material opposed to a hook has a greater surface area, and willbe in contact with the roof rack cross bar over a greater surface area. The interaction of this greater surface area with the cross bar will assist in the dissipation and transmission of such forces as may act upon the first rate member 401.

According to this specific embodiment of the present invention the disk of material 401 which makes up the first frame member has been further modified so as to comprise a bar gripping means 403. This bar gripping means 403 is in the form of a groove made into the disk 401. As previously explained in relation to Figure 3, this groove is configured such that a cross bar portion may be fitted into the groove 403 so connecting the disk 401 to the cross bar in a non- permanent fashion.

With reference to Figure 5 herein there is shown a further non-permanent cross bar locking means comprised within a first frame member 501. With reference to Figure 5 herein there is shown a first frame member 501 which comprises a straight portion and a hooked portion much as described in relation to Figures 2 and 3 herein previously.

In Figure 5 there is shown a cross bar member 502 in cross section, in Figure 5 the first frame member 501 is shown substantially abutting the cross bar member 502 via the interior surface of the hooked portion of the first frame

P1 363.Specification 012505

member 501. Not shown in this Figure is the remainder of the ladder clamping device as previously described in relation to Figure 2. The first frame member 501 further comprises cross bar clamping means 503. This cross bar clamping means takes the form of a piece of material hinge 3 attached to an end 504 of the first frame member 501. The cross bar fixing means is therefore capable of movement about this pivot 504 and in this way can allow access to the hook portion of the frame member 501 or not depending upon its configuration.

The cross bar clamping means 503 is offset relative to the main body of the first frame member 501.

This device may be used as follows, the cross bar securing means 503 is pivoted such that access to the interior of the hook portion of the first frame member 501 is possible. The first frame member 501 is then positioned such that the cross bar means 502 is located within the hooked portion of the first frame member. The cross bar securing means 503 is then pivoted about at pivot 504 such that it comes into physical contact with the cross bar member 502. The cross bar securing means 503 comprises a hole as does the first frame member 501, these holes are configured to line up when the cross bar securing means is in contact with the cross bar 502. A pin may therefore be placed through the cross bar securing means 503 into the first frame member 501 so securing the cross bar 502 relative to the first frame portion 501.

With reference to Figure 6 herein there is shown a further embodiment of the present invention in which the first frame member 601 and second frame member 602 do not move relative to each other via said first frame member 601 as previously described. In this instance the first frame member is again comprised of two portions, a first substantially straight portion and a second hooked portion suitable for interacting with the underside of a cross bar from a roof rack.

P1 363.Specification.0 12505

The second component of the device is a trigger activated adjustment means connected to a second frame member 602. This trigger activated adjustment means 603 again comprises a first and second trigger portions 604 and 605 respectively.

As previously described by an operator bringing the second trigger 605 towards the first trigger 604 this causes movement of the second frame member 602 towards the hooked region of the first frame portion 601. This adjustment, however, does not take place via movement along the length of the first frame member 601. The position of the adjustment means 603 relative to the first frame portion 601 is fixed via an adjustment screw or other suitable means 606.

This fixing screw 606 allows the adjustable positioning means 603 to be placed anywhere along the length of straight portion of the first frame member 601.

When the fixing screw 606 is engaged the body of the adjustment means 603 is fixed relative to the first frame member 601. The second frame member 602 is positioned upon a second pole 607, the movement of which is controlled by the operation of the second trigger 605.

In order to securely affix the adjustment means 603 to the first frame member 601 holes may be provided in the relevant portion of the first frame member 601 such that the fixing screw 606 may be configured to enter the first frame member so securing the adjustment means 603 to the first frame member.

With reference to Figure 7 herein there is shown a means configured to prevent the unwanted activation of the locking means previously described in relation to Figure 2. With reference to Figure 7 A herein there is shown a close up view of the locking mechanism associated with the ladder clamping device, Shown is the first frame member 701 which runs through the locking means 702, also shown are the biasing means 703 and the end piece 704. The operation of such a mechanical arrangement has previously been described and such a explanation will not therefore be repeated.

P1 363.Specification.O1 2505

With reference to Figure 7 B herein there is shown an identical locking means as described in Figure 7 A with the addition of a safety device 705 which has been fitted about the first frame member 701 and the locking means 701 so as to hold the locking means 702 in a locked configuration. As is shown in Figure 7 C herein this locking means 705 is a block of material from which portions have been removed, these being a first portion corresponding with locking means at one side of the first frame member and a second portion corresponding with the locking means at a second side of the first frame portion. The device 705 has further material removed corresponding to the first frame member 701.

This safety device may be used as follows, with the locking means in a locked configuration, the block which comprises the safety device 705 is inserted into the space surrounding the first frame member immediately adjacent to the locking means 702. The safety device 705 is made from a rubber or elastic/plastic material and therefore forms a snug fit when fitted about this means. Because of the direct physical contact between portion 706 and 707 with the locking means 702, the locking means is prevented from deactivating and continues to prevent the movement of the first and second frame members relative to each other.

With reference to Figure 8 herein there is shown a further embodiment of the present invention in which a safety device 801 much as previously described in relation to Figure 7 herein which has been fitted to the interior of a door 802, this door being configured to perform 2 functions, firstly, when closed over the locking means the safety device interacts with said locking means preventing the unwanted deactivation of the breaks which secure the first and second frame members in a fixed orientation relative to each other. Secondly, it double protects the interior of the mechanism from exterior articles such as stones, pebbles etc, again helping to prevent the accidental deactivation of the locking mechanism. Finally, this door may comprise a further mechanism which allows a locking of the door over the locking means, therefore, in the absence of a suitable locking means in this instance, a key entry into unlocking mechanism would be

P1 363.Specification.O1 2505

denied and movement of the first and second frame members relative to each other would be presented stopping an unauthorized person from removing the ladder clamping device from a set of ladders.

P1 363.Specification.O 12505

Claims

Claims: 1. A clamping device comprising two frame members, wherein each

frame has an associated clamping face; and the frame members are arranged in a relatively moveable relationship so that the two frame members are in an opposed spaced apart relationship; the device further comprising handle means such that when in use hand pressure on the handle means will effect relative movement of the frame members so as to move the clamping faces towards each other; there being a releaseable locking means associated with the frame members which use acts to maintain the relative positions of the clamping faces when the hand pressure is released.

2. A clamping device as claimed in claim I which is operable using one hand.

3. A clamping device as claimed in claim I or 2 in which the frame members are in a relatively slideable relationship.

4. A clamping device as claimed in any preceding claim in which spring means move the clamping faces apart when the locking means is released.

5. A clamping device as claimed in any preceding claim in which the clamping action is indexed.

6. A clamping device as claimed in any preceding claim in which the locking of the locking means is achieved by frictional engagement.

P1 363.Specificatton 012505 7. A clamping device as claimed in any preceding claim in which the second frame member has handle means formed integrally with it.

8. A clamping device which includes first and second device members slideably removeable relative to one another between a clamping position in which an object is clamped and a release position in which said object is released and means for anchoring the relative movement of the first and second device members when in the clamping position.

P1 363.Specification.O1 2505

Amendments to the claims have been filed as follows 1. A ladder-clamping device comprising two frame members, wherein each frame has an associated clamping face; and the frame members are arranged in a relatively moveable relationship so that the two frame members are in an opposed spaced apart relationship; the device further comprising handle means such that when in use hand pressure on the handle means will effect relative movement of the frame members so as to move the clamping faces towards each other; there being a releaseable locking means associated with the frame members which acts to maintain the relative positions of the clamping faces when the hand pressure is released.
2. A ladder-clamping device as claimed in claim 1 which is operable using one hand.
3. A ladder-clamping device as claimed in claim I or 2 in which the frame members are in a slideable relationship relative to each other.
4. A ladder-clamping device as claimed in any preceding claim in which spring means move the clamping faces apart when the locking means is released.
5. A ladder-clamping device as claimed in any preceding claim in which the clamping action is indexed.
6. A ladder-clamping device as claimed in any preceding claim in which the locking of the locking means is achieved by frictional engagement.
7. A ladder-clamping device as claimed in any preceding claim in which the second frame member has handle means formed integrally with it.
8. A ladder-clamping device as claimed in any preceding claim comprising a safety device, configured to hold said locking means in a locked position when in use preventing movement of said frame members relative to each other.
9. A ladder-clamping device as claimed in any preceding claim wherein said first frame member comprises a disc of material.
10. A ladder-clamping device as claimed in any preceding claim wherein said disc of material comprises a groove configured to accept a cross bar portion of a vehicle roof rack.