Technical Field of the Invention

The present invention relates to a ladder guard. In particular, the present invention relates to a ladder guard comprising rails and/or an integrated restricting element.

Background to the Invention

Ladders are commonplace in scaffolding assemblies on construction sites. Ladders typically comprise two vertical support members, known as stiles, stringers or rails, connected by horizontal support members, known as rungs. Ladders can be used to allow workers to access working platforms and thereby safely access parts of a building site that would otherwise be out of reach. When a construction site is vacated, or a particular platform is not in use, it is desirable to restrict access to the platform in order to reduce the risk of members of the public climbing onto the platform and falling from height.

Ladder guards are used to restrict unauthorised access to a ladder to which they are attached. Guidance published by the Health and Safety Executive sets out a number of requirements for ladder guards. Of particular importance, the ladder guard should attach to the ladder to make each covered rung unusable. A further requirement is that guards need to be matched to certain ladders and not used on others i.e. a narrow guard is only suitable for a narrow ladder and if used on a wide ladder sufficient rung width could be exposed to allow the ladder to be climbed.

A typical ladder guard comprises a rectangular plate which is placed against the rungs of a ladder and is chained and/or padlocked to the rungs of the ladder to secure it in place. In some prior art ladder guards, the plate may be lifted over a stile and slid across to one side to expose a portion of the rungs. Thus, the ladder may still be usable even with the guard attached.

Wooden and metal ladders, as are commonly found in the industry, tend to have different dimensions. Numerous ladder guards of different types and sizes must therefore be stored on-site in order to match each ladder with a suitable ladder guard. Chains and/or padlocks used to secure the ladder guard to the ladder may not be suitable for use with all ladder guards. Various types of chains and padlocks must also be stored on-site and are laborious to transport alongside the ladder guards themselves.

Ladder guards are typically used on ladders that are placed outside and are vulnerable to the elements. The use of ladder guards on ladders exposed to adverse weather conditions can create health and safety hazards. For example, the rectangular body of the guard makes the ladder with a conventional ladder guard attached, more susceptible to being caught in high winds that would usually pass through the gaps between the ladder rungs. The ladder guard can also make it difficult to inspect the condition of the ladder without removing the guard first.

Existing ladder guards are also be health and safety hazards themselves. Solid metal designs can be heavy and awkward to handle and install. This could result in manual handling injuries, the guard being incorrectly installed or the installation of the guard being abandoned altogether, leading to potential unauthorised access to a construction site. In addition, when handling the guard in adverse weather, the rectangular body is susceptible to being caught in the wind, amplifying the risks associated with manual handling of the guard.

It is an object of embodiments of the present invention to provide an improved ladder guard and/or to address one or more of the problems presented above.

Summary of the Invention

According to a first aspect of the present invention there is provided a ladder guard comprising: an elongate plate having a front face and a rear face; and one or more hook members projecting rearwardly from the rear face of the elongate plate, each hook member adapted to releasably engage with a rung of a ladder, wherein the elongate plate comprises a mesh.

The elongate plate allows the ladder guard, when installed on the ladder, to obstruct a sufficient width and number of ladder rungs to prevent foot placement on the covered rungs, and thereby prevent unauthorised access to the ladder. That each hook member is adapted to releasably engage with a rung allows the ladder guard to be installed and removed repeatedly. The mesh advantageously reduces the weight of the ladder guard and enhances its performance. The openings in the mesh also allows the wind to pass through the ladder guard, making it easier to handle and reducing the likelihood of a ladder being blown over or away once fitted with the ladder guard. The mesh also allows inspection of the ladder once fitted with a ladder guard. The strength/security of the ladder guard is not compromised by the mesh as the mesh can be a variety of different thicknesses or strengths to suit the anticipated security risks.

The ladder guard may comprise first and second hook members. The first and second hook members may be spaced apart along an elongate axis of the plate such that when the ladder guard is engaged with the ladder, movement of the ladder guard relative to the ladder is restricted in a direction perpendicular to the rear face. Two hook members allow for the ladder guard to be securely engaged with the ladder at two points. The first and second hook members being spaced apart along the elongate axis advantageously prevents rotation of the ladder guard about an axis parallel to the rungs and provides a method of restricting movement of the ladder guard relative to the ladder in a direction perpendicular to the rear face.

The elongate plate may be substantially rectangular. The elongate plate may be dimensionally matched to the ladder. The width of the elongate plate may be sized to cover a part or all of the rung width. The width of the elongate plate may be sized to extend over the stiles of the ladder. The length of the elongate plate may be sized to cover 5 or more of the rungs of the ladder. In one example, the plate may have a length of between, say, 1000mm and 3000mm, a width of between, say, 350mm and 550mm, and a thickness of between, say, 1mm and 10mm. By this construction, the elongate plate is adapted to fit a range of ladders commonly found in the industry. The elongate plate may be made from sheet metal. In particular, the elongate plate may be made from steel or aluminium. Alternatively, the elongate plate may be made from fibreglass.

The elongate plate may comprise a mesh and a rigid border region. The first and second hook members may each be supported by a rigid member or structure disposed between respective sides of the rigid border region of the elongate plate. The mesh may be a wire mesh. The mesh may be a perforated metal sheet. The perforated metal sheet may be made from aluminium. The border region may be sheet metal. The mesh may be an expanded metal sheet. Additionally or alternatively, different sections of the elongate plate may be or include mesh or a solid sheet. Different sections of the elongate plate may be made from different materials.

The rigid border region may comprise four rigid elongate members. The rigid elongate members may comprise two vertical side members. The two side members may be substantially parallel to one another. The two side members may be substantially perpendicular to the ground in use.

The rigid elongate members may comprise two horizontal transverse members. The transverse members may be substantially parallel to one another. The transverse members may be substantially parallel to the ground in use.

The two side members and two transverse members may be connected to form a substantially rectangular frame. The elongate plate may comprise the frame and one or more fill members. The fill member may span the aperture within the frame. The fill member may be a mesh.

The elongate plate may comprise one or more additional rigid elongate members that span the fill member. In this configuration, the one or more additional rigid elongate members may support or brace the fill member.

One or more additional rigid elongate members may span an opening in the frame. The one or more additional rigid elongate members may be oriented between the two vertical side members and/or between the two horizontal transverse members. In this configuration, the one or more additional rigid elongate members may create multiple openings into which a fill member may be provided.

The ladder guard can be adapted to suit various needs of strength and durability by supporting the mesh with a rigid frame. The frame can feature additional rigid members that facilitate securing of additional hooks or attachments in the case where the mesh is not strong enough to support them.

Each hook member may comprise a shank and a foot. The first hook member may be positioned substantially toward a first end of the elongate plate. The shank of the first hook member may be positioned substantially toward a first end of the elongate plate. The shank may project from one end of the elongate plate. The second hook member may be positioned substantially toward a second end of the elongate plate. The shank of the second hook member may be positioned substantially toward a second end of the elongate plate. Advantageously, where the first hook member is positioned substantially toward a first end and the second hook member is positioned substantially toward a second end, the hook members thereby ensure that a portion of the ladder guard cannot be bent away from the ladder.

The shank of the first and/or second hook member may project substantially perpendicularly from the rear face. The first and/or second hook member may be formed from a single piece. The single piece may be bent at a joint between the shank and the foot. In this manner, a single piece of metal sheet can be bent to form a hook member. The foot of the first and/or second hook member may extend in a direction substantially parallel to the length of the rear face. The foot of the first and second hook member may extend in the same direction.

The first and/or second hook member may be made from sheet metal. In particular, each hook member may be made from steel or aluminium. Alternatively, the first and/or second hook member may be made from fibreglass. The first and/or second hook member may be welded or bonded to the elongate plate.

The foot of the second hook member may not protrude beyond the second end of the elongate plate. The foot of the second hook member may be longer than the foot of the first hook member in the direction of the elongate axis. Advantageously, the longer foot of the second hook member allows the ladder guard to be compatible with the different rung separations of various ladders found in the industry.

The shank of the first and/or second hook member may have a greater extent in the direction of a transverse axis substantially parallel to the plane of the rear face of the elongate plate than in the direction of a longitudinal axis perpendicular to the transverse axis. Thus, the shank of the first and/or second hook member may be a wide shank. The shank of the first and/or second hook member may extend in the direction of the transverse axis a distance so as not to extend beyond the sides of the elongate plate. Thus, the shank of the first and/or second hook member may be narrower than the width of the elongate plate. In this manner, where the elongate plate is sized to extend over the stiles of the ladder, the first and/or second hook member can fit between the stiles.

In one embodiment, the shank of the first hook member and/or second hook member may have a width of between, say, 100mm and 450mm. The foot of the first and/or second hook member may have the same or substantially the same width as the shank. The shank of the first hook member may have substantially the same width as the shank of the second hook member. The shank of the first and/or second hook member may project beyond the rearward extent of the or each rail.

The ladder guard may comprise one or more carry handles. The carry handles may be disposed on one or more of the rails. The carry handles may project away from the ladder guard in the plane of the elongate plate. The carry handles allow easy installation and handling of the ladder guard.

The ladder guard may further comprise one or more rails projecting rearwardly from the elongate plate, the one or more rails positioned to demarcate a slot between each rail and one or both of the hook members such that when the ladder guard is engaged with a ladder, a ladder stile can be received in the slot. One or more rails are advantageous as they can be sized to extend over the outer surfaces of the ladder stiles, or to sit between the stiles, in order to prevent the hook members from being slid along the rungs to expose the rungs. If the ladder guard is slid along the rungs, the rails will contact the stiles to prevent any further lateral movement of the ladder guard.

The one or more rails may be parallel to the elongate axis (of the ladder guard and/or the ladder). The one or more rails may project from the or each side of the elongate plate.

The plate and the one or more rails may be formed from a single piece. The single piece may be bent at a joint or bend line between the plate and the or each respective rail.

Two rails may project rearwardly from the elongate plate. One rail may project rearwardly on each lateral side of the elongate plate. Where the ladder guard comprises two rails, the rails may be substantially parallel to one another. The one or more rails may extend along a part of the length of the elongate plate. The one or more rails may extend the full length of the elongate plate. The one or more rails may be substantially rectangular. Where the ladder guard comprises rails, the shank of the first and/or second hook member may project beyond the rearward extent of the rails.

The ladder guard may further comprise a restricting element operable to extend between one of the hook members and the elongate plate such that when the ladder guard is engaged with a ladder, movement of the ladder guard relative to the ladder is restricted in a direction substantially parallel to the rear face. This is because when the ladder guard is engaged with the ladder a rung is received in the hook member which comprises the restricting element, and when the restricting element is operated to extend between that hook member and the elongate plate, the rung is trapped between the hook member, rear face of the plate and restricting element. Movement of the ladder guard in a direction substantially parallel to the rear face results in the engaged rung contacting the restricting element and further movement of the ladder guard is thereby prevented. The restricting element may be operable to extend partially or completely between the foot of the hook member and the elongate plate. The restricting element may be operable to releasably connect the hook member to the plate. The restricting element may be operable to extend between the first hook member and the elongate plate.

One of the hook members may comprise a first aperture. The first aperture may be positioned substantially centrally across the width of the foot of the hook member. The first aperture may be positioned substantially toward the free end of the foot. The elongate plate may comprise a second aperture which is coaxial with the first.

The restricting element may comprise a fitting extending between the first and second apertures. The fitting may be a bolt. The bolt may comprise a head and a body. The body may comprise a threaded end portion. A flange may project from the body of the bolt. The fitting may be a tamper resistant bolt. An engaging formation formed in the head of the bolt may comprise four distinct straight grooves, each groove separated by, say, 90 degrees or so. An engaging formation may comprise a shaped opening formed in the head of the bolt to receive a tool or driver. The shaped opening may be shaped to receive a specialist Allen key for example. A nut comprising an inner threaded bore may be attached to the foot. By this construction, the bolt may be engaged with the nut to form a connection between the elongate plate and the foot. The nut may be welded to the foot. The inner threaded bore of the nut may be coaxial with the first and/or second aperture. The nut may be attached to the outer surface of the foot. The inner threaded bore of the nut may have a diameter less than the diameter of the aperture. Alternatively, the first aperture may comprise an internal thread suited to cooperate with the thread of the bolt. By this construction, the bolt can be inserted through the second aperture and the threaded end of the bolt can be engaged with the nut or threaded first aperture - the head of the bolt contacting the front face of the elongate plate.

Detailed Description of the Invention

In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

Figure 1 is a perspective view of a ladder guard;

Figure 2 is a perspective view of the underside of the ladder guard of Figure 1;

Figure 3 is an enlarged perspective view of the upper portion of the underside of the ladder guard of Figure 1 with the bolt disengaged from the nut;

Figure 4 is a side view of the ladder guard of Figure 1 ;

Figure 5 is a top view of the ladder guard of Figure 1 ;

Figure 6 is a bottom view of the ladder guard of Figure 1 ;

Figure 7 is a perspective view of the ladder guard of Figure 1 installed and engaged with a ladder;

Figure 8 is a perspective view of the underside of the ladder and ladder guard installation of Figure 7 ;

Figure 9 is a perspective view of another ladder guard fitted to a ladder; and

Figure 10 is an enlarged perspective view of the upper portion of the underside of the ladder guard of Figure 9. In what follows the terms upper, lower, top, bottom, left and right are used to refer to the invention in the orientation in which it is illustrated which is the orientation in which it is intended to be used, but should not be taken as otherwise limiting. The drawings are not to scale.

Referring now to Figures 1 - 6, a ladder guard 1 comprises an elongate metal plate 2 having a front face 3 and a rear face 4. In this embodiment, the elongate plate 2 is substantially rectangular.

A rail 5, 6 projects rearwardly from each long side of the plate 2, in a direction perpendicular to the rear face 4. The rails 5, 6 extend along the full length of the plate 2 from the side of the elongate plate. In this embodiment, the plate 2 and rails 5, 6 can be one-piece formed by bending a rectangular metal sheet at each long side of the sheet along a line parallel to the long side.

A first hook member 7 projects rearwardly from the rear face 4 of the plate 2 at an upper end. The first hook member 7 comprises a wide shank 8 which bends smoothly round toward the rear face 4 into a foot 9 which extends down substantially parallel to the rear face 4. An inner surface 10 and outer surface 11 of the first hook member 7 are thereby defined.

The shank 8 projects substantially perpendicularly from the rear face 4, and is parallel to the short sides of the plate 2. In this exemplary embodiment, the upper side of the plate 2 and outer surface of the shank 8 are vertically aligned.

The width of the first hook member 7 is less than the width of the plate with the side rails 5, 6 formed. The wide shank 8 of the first hook member 7 is centered in the middle of the upper short side of the plate 2 such that there is an equal slot 34, 35 between the side of the first hook member 7 and the side rail 5,6 either side of the first hook member 7.

A first circular aperture 14 is formed in the foot 9 toward the free end and centrally located across the width of the foot 9. A nut 15 is attached to the outer surface of the foot 9 over the first aperture 14 such that the internal threaded bore of the nut 15 is coaxial with the first aperture 14. In this exemplary embodiment, the nut 15 is welded to the foot 9. The diameter of the bore is less than the diameter of the first aperture 14 such that the thread can be engaged in a direction from the inner surface of the foot 10.

A second circular aperture 16 is formed in the plate 2 and is coaxial with the first aperture 14.

A bolt 17 extends down through the second aperture 16. The bolt 17 comprises a head 18 and a body 19. The underside of the head 18 provides a bearing surface between the bolt 17 and the front face 3 of the plate 2. In this exemplary embodiment, the bolt 17 is a tamper resistant (or“tamper-proof’) bolt 17; that is, the head 18 comprises a uniquely designed engagement formation and the matching driver is not widely available. Alternatively, the engagement formation of the head 18 can be a specialist Allen key fitting.

The body 19 comprises a threaded end portion 20 suitable to cooperate with the internal thread of the nut 15. The body 19 between the threaded end portion 20 and the head 18 is unthreaded. A flange 21 projects circumferentially from the body 19 to separate the threaded and unthreaded portions of the body 19.

When the bolt 17 is threaded into the nut, the underside of the head 18 contacts the front face of the plate and the flange 21 on the body contacts the inner surface 10 of the foot 9 simultaneously. When this occurs, the bolt 17 cannot be threaded any further into the nut 15.

A second hook member 22 projects rearwardly from the rear face 4 of the plate 2 toward the lower end of the plate 2. The second hook member 22 comprises a wide shank 23 which bends smoothly round toward the rear face into a foot 24 which extends down substantially parallel to the rear face 4. An inner surface 25 and outer surface 26 of the second hook member 22 are thereby defined. The foot 24 of the second hook member 24 is longer than the foot 9 of the first hook member 7. As a result, the ladder guard 1 is adapted for use with ladders of differing rung separations.

The shank 23 projects substantially perpendicularly from the rear face 4, and is parallel to the short sides of the plate 2. In this exemplary embodiment, the shank 23 is positioned in from the lower end of the plate 2 such that the foot 24 does not extend beyond the lower side of the plate 2. The second hook member 22 has the same or substantially the same width as the first hook member 7. As a result, the width of the second hook member 22 is less than the width of the plate 2 with the side rails 5, 6 formed. The wide shank 23 of the second hook member 22 is centered in the middle of the width of the plate 2 such that there is an equal slot 35, 36 between the side of the second hook member 22 and the side rail 5, 6 either side of the second hook member 22.

Turning now to Figures 7 and 8, a ladder 29 comprises two vertical support members 30, known as“stiles” and a plurality of horizontal support members 31, known as“rungs”. The ladder guard 1 is typically installed on the ladder 29 with the ladder in an upright position, with the base of the stiles 32 planted on the ground and an upper part of the stiles 33 leaning against a platform above.

To install the ladder guard 1 on the ladder 29, the bolt 17 is initially unthreaded from the nut 15 and the head 18 is pulled away from the front face 3 of the plate 2 until the flange 21 contacts the rear face 4 of the plate 2. With the bolt 17 in this retracted position, the ladder guard 1 is placed onto the ladder 29 to position the stiles 30 in the slots 34 - 37 between the respective hook member 7, 22 and side rail 5, 6. The first hook member 7 is inserted into the space between a first rung 31a and the rung above 3 lb, and the second hook member 22 is inserted into the space between a second rung 31c and the rung above 3 Id. In this position, the side rails 5, 6 extend over the outer surfaces of the stiles 30.

The ladder guard 1 is then lowered to releasably engage the first hook member 7 with the first rung 31a and the second hook member 22 with the second rung 31c.

The first hook member 7 is lowered behind the first rung 31a until the inner surface of the shank 8 comes into contact with the first rung 31a. In doing so, the first rung 31a is brought into the first hook member 7 through the gap between the end of the bolt 20 and the inner surface of the foot 9. The second hook member 22 is simultaneously lowered behind the second rung. In this exemplary embodiment, the shank of the second hook member 23 contacts the second rung 31c. However, the foot 24 need only extend down behind the second rung 31c, and the shank 23 need not contact the second rung 31c, for movement of the ladder guard to be restricted in a direction perpendicular to the rear face 4. To prevent removal of the ladder guard 1 from the ladder 29 on which it is installed, the bolt 17 is inserted through the second aperture 16 and is threaded into the nut 15 below by turning the head 18 using a suitable driver. Following this, the first rung 3 la is retained within the first hook member 7 by the bolt 17, and the ladder guard 1 cannot be moved upwards a distance sufficient to disengage the second rung 31c from the second hook member 22.

With the ladder guard 1 installed and the bolt 17 engaged with the nut 15, the ladder 29 cannot be accessed by moving the ladder guard 1 in a direction perpendicular to the rear face 4 (as the engaged rungs 31a, 31c will be brought into contact with the hook members 7, 22) nor in a direction parallel to the rear face 4 (as the first rung 31a will be brought into contact with the bolt 17) nor can the ladder guard 1 be lifted and slid over the ladder stiles 30 (as the side rails 5, 6 and/or the side of the hook members 7, 22 will prevent movement over the ladder stiles 30). It is therefore not possible for an unauthorised person to use the portion of the ladder 29 covered by the ladder guard 1.

To remove the ladder guard 1 from the ladder 29, the bolt 17 is disengaged from the nut 15 and the head 18 is pulled away from the front face 3 of the place 2 until the flange 21 contacts the rear face 4 of the plate 2. With the bolt 17 in this retracted position, the ladder guard 1 is raised in a direction parallel to the axis of the stiles 30 to disengage the first hook member 7 from the first rung 31a and the second hook member 22 from the second rung 3 lc. The ladder guard 1 is then removed by pulling the ladder guard 1 away from the ladder 29 in a direction substantially perpendicular to the rear face 4.

Turning now to Figures 9 and 10, a ladder guard 1 according to an embodiment of the present invention is shown fitted to a ladder 29. This embodiment is similar to the embodiments shown in Figures 1 - 8 but has a few important differences. Firstly, the elongate plate 2 is formed from a mesh 40 and a rigid border 41 rather than a single plate. The border 41 defines the edges of the plate 2 and is made from sheet metal with two rails 5, 6 that project from the sides of the border 41, as with the plate 2 shown in Figures 1 - 8. The width of the border 41 is approximately 50 mm along the elongate sides of the plate 2 and at the bottom of the plate 2. The top of the border 41 is wider than the rest of the border 41 and features a wide support plate 42. The first hook member 7 attaches to the support plate 42 and the width of the support plate 42 is substantially the same as the length of the foot 9 of the first hook member 7. The support plate 42 and first hook member 7 can therefore be fitted with a restricting element of the type described in Figures 1 - 8 to prevent removal of the ladder guard 1 from the ladder 29. To support the second hook member 22, an elongate sheet metal support plate 43 is installed between the sides of the border 41. The support plate 43 is approximately 40 mm in width and the second hook member 22 is attached to it. The mesh 40 is an expanded metal sheet that is disposed within the aperture defined by the rectangular border 41, restricting access to the ladder 29.

Secondly, the ladder guard 1 shown in Figures 9 and 10 features carry handles 44 disposed on each side rail 5, 6. The carry handles 44 project away from the ladder guard 1 in a direction parallel to the plane formed by the plate 2 and perpendicular to the elongate axis of the plate 2. The carry handles 44 are formed from a single metal pole of diameter approximately 10 mm, bent into a squared U- shape and welded to the rails 5, 6 by the tips of the pole to form a rectangular handle.

The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.