Ladder clamp

Abstract

A ladder clamp (100) for securing a ladder to a support structure, the ladder clamp (100) comprising: a clamp body (101) comprising a proximal end (102) having at least two laterally disposed footings (104, 105) for mounting the proximal end (102) on a first ladder rung and a distal end (103) having an engagement surface (115) for engaging the distal end (103) with a second ladder rung longitudinally spaced from the first ladder rung; a strap (117) having a fixed end (119) secured to the clamp body (101) at a position between the proximal end (102) and the distal end (103), the strap (117) extending over a tensioning element (120) disposed on the clamp body (101) at a location towards the distal end (103) and then through an aperture (121) located in the clamp body (101) to a free end (123); a lever (132) associated with the tensioning element (120) and adapted to move the tensioning element (120) between a first orientation in which it rests under the strap (117) and a second orientation in which it applies increased tension on the strap (117) in use; a strap retaining assembly disposed on the proximal end (102) of the clamp body (101) and comprising at least two opposed retaining surfaces (127,129) through which the free end (123) of the strap can be fed towards the distal end (103) of the clamp body (101), thereby retaining the strap (117) between the retaining surfaces (127, 129).

Description

[0001] LADDER CLAMP

[0002] FIELD OF INVENTION

[0003] The present invention relates to a ladder clamp. More particularly, the invention relates to a ladder clamp for quickly and safely securing ladders to vehicle racks, such as roof racks.

[0004] BACKGROUND ART

[0005] Ladders are regularly transported to and from work sites on vehicle racks. Typically, ladders are secured using either bungee cords, ropes, tie down straps, ratchet straps, ladder clamps or a combination of these devices. These devices are often applied in haste and have several inherent issues.

[0006] Bungee cords are a quick method of tying down an object however they are not suitable for load bearing situations such as securing a ladder to vehicle racks. Although there are many instances that people may use these devices to quickly secure a ladder to vehicle racks, they do not pass the required regulatory approvals and have been known to fail during transport.

[0007] Ropes are often used to secure ladders to vehicle racks as they are commonly available and inexpensive. Ropes are cost effective however a considerable amount of time must be taken to ensure the rope has been tensioned and tied off correctly and inspected for damage to ensure the ladder is safely secured to the vehicle rack. Ropes are often left improperly tensioned allowing the ladder to move during transport. Ropes typically have a limited serviceable life span and often do not meet regulatory approvals.

[0008] Tie down straps provide a cost effective and quick method for securing ladders to vehicle racks however they have no means of applying additional tension. Tie down straps are often left under tensioned, allowing the ladder to move during transport. Another issue is that the mechanical components of a tie down strap are open to the elements and can fail prematurely.

[0009] Ratchet straps are an effective method of safely securing a ladder to vehicle racks, however the correct installation procedure is time consuming. The metal components of a ratchet strap can cause damage to the vehicle as they are being threaded between the vehicle racks and the vehicle in haste and also as the device is being operated if the components are located too close to the vehicle. As with a tie down strap, the mechanical components of the device are typically left open to the elements and can fail prematurely.

[0010] Ladder clamps provide good tension to secure ladders to vehicle racks, however they require the user to be in an elevated position to access and install the device and the installation procedure is generally time consuming. Ladder clamps, such as the device disclosed in U.S. Pat. No. 201 1 / 028606 A1 , typically consist of a clamping bar component that transverses the side rails of the ladder and a hook component with an elongated protrusion that passes through an aperture in the clamping bar and a hook that partially envelopes the vehicle rack. Due to the many varied types of ladders, ladder clamps are mostly suited to securing narrower ladder types as the clamping bar is typically too short to transverse the rails of wider ladder types. Typical ladder clamps have an elongated protrusion on the hook that protrudes vertically above the device, increasing the minimum height of the vehicle to an undesirable level and increasing the chance of damage to both the ladder clamp and overhead obstructions. In addition, in the event that a ladder clamp loses tension and becomes loose it is possible that the ladder clamp can fall between the ladder rails and steps allowing the ladder to break free of the vehicle racks.

[0011] Most of the above-mentioned devices provide little to no protection against theft.

[0012] The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate exemplary technology areas where some embodiments described herein may be practiced

[0013] Various aspects and embodiments of the invention will now be described.

[0014] SUMMARY OF INVENTION

[0015] As mentioned above, the present invention relates generally to a ladder clamp. More particularly, the invention relates to a ladder clamp for quickly and safely securing ladders to vehicle racks, such as roof racks.

[0016] According to one aspect of the invention there is provided a ladder clamp for securing a ladder to a support structure, the ladder clamp comprising: a clamp body comprising a proximal end having at least two laterally disposed footings for mounting the proximal end on a first ladder rung and a distal end having an engagement surface for engaging the distal end with a second ladder rung longitudinally spaced from the first ladder rung; a strap having a fixed end secured to the clamp body at a position between the proximal end and the distal end, the strap extending over a tensioning element disposed on the clamp body at a location towards the distal end and then through an aperture located in the clamp body to a free end; a lever associated with the tensioning element and adapted to move the tensioning element between a first orientation in which it rests under the strap and a second orientation in which it applies increased tension on the strap in use; a strap retaining assembly disposed on the proximal end of the clamp body and comprising at least two opposed retaining surfaces through which the free end of the strap can be fed towards the distal end of the clamp body, thereby retaining the strap between the retaining surfaces.

[0017] While it is envisaged that the clamp body may include more than two footings, for example three or four or more footings, in a preferred embodiment the clamp body includes two footings. Preferably, each of the laterally disposed footings comprises a rearward facing toe and a forward facing toe that define an angular mounting surface adapted to be mounted on the first ladder rung.

[0018] The form of the proximal end of the clamp body is not particularly limited. In a preferred embodiment, the clamp body comprises at least two laterally spaced sections extending either side of the proximal end, the laterally disposed footings being disposed beneath a respective laterally spaced section.

[0019] In a preferred embodiment the distal end comprises an elongate tongue extending from the strap retaining assembly. To assist in engaging the distal end with the second ladder rung, the elongate section preferably comprises a layer of compressible material on an underside thereof defining the engagement surface.

[0020] The strap may be formed from any suitable material, for example nylon, polyester, polypropylene and so on. Preferably, the strap is reinforced, for example with one or more cables extending longitudinally within or on the strap.

[0021] In certain embodiments the strap may include a raised tab and / or an eyelet on the free end thereof for assisting in grasping or securing the free end.

[0022] The tensioning element may take any suitable form provided it is movable between a first orientation in which it rests under the strap and a second orientation in which it applies increased tension on the strap in use. Preferably, the tensioning element comprises an eccentric cam mounted for rotation between the first orientation and the second orientation.

[0023] The lever may be mounted for rotation in any suitable manner. For example, this may be a side mounted lever. However, the lever preferably comprises a U-shaped handle longitudinally mounted on an upper surface of the clamp body, the handle being rotatable between a first orientation in which it extends away from the upper surface of the clamp body, downwards toward the distal end of the clamp body to a second orientation in which it is disposed along the upper surface of the clamp body, wherein the first orientation of the handle corresponds with the first orientation of the tensioning element and the second orientation of the handle corresponds with the second orientation of the tensioning element.

[0024] In order to ensure the handle is in the second orientation during transport, the ladder clamp preferably further comprises a latch for securing the handle in the second orientation.

[0025] The strap retaining assembly may take any suitable form. However, in a preferred embodiment, the strap retaining assembly comprises a pawl mounted above the strap and defining a first retaining surface that engages an upperside of the strap, and a fixed block disposed on the proximal end of the clamp body and defining a second retaining surface that engages a corresponding under-side of the strap. Preferably, an upper end of the pawl, disposed away from the first retaining surface, is moveable between a first orientation in which the first retaining surface engages the upper-side of the strap and a second orientation in which the first retaining surface disengages the strap thereby facilitating release of the strap from the strap retaining assembly.

[0026] A ladder clamp may further comprise a lock for locking the strap retaining assembly, thereby preventing release of the strap from the strap retaining assembly. In that regard, for security and longevity, the ladder clamp preferably further comprises a housing that houses the strap retaining assembly.

[0027] The clamp body is preferably formed from resilient material, such as a resilient thermoplastic material. This enables the clamp body to flex under tensioning ensuring secure engagement of the ladder clamp with the ladder and support structure.

[0028] The support structure may be any structure to which the ladder is to be clamped. For example, the support structure may generally comprise a roof rack for a vehicle. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

[0029] To further clarify various aspects of some embodiments of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It should be appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting on its scope. The invention will be described and explained with additional specificity and detail through the accompanying drawings in which:

[0030] FIG. 1 illustrates a perspective view of a ladder clamp.

[0031] FIG. 2 illustrates a perspective view of a ladder clamp in situ securing a ladder to a vehicle rack.

[0032] FIG. 3 illustrates a sectional side view of a ladder clamp.

[0033] FIG. 4 illustrates a sectional side view of a ladder clamp with enlarged DETAIL

[0034] B.

[0035] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that limiting the description to the preferred embodiments of the invention is merely to facilitate discussion of the present invention and it is envisioned without departing from the scope of the appended claims.

[0037] Referring to Figures 1 and 2, a ladder clamp 100 is illustrated. The ladder clamp 100 includes a clamp body 101 that has a proximal end 102 and a distal end 103. The proximal end 102 includes two laterally disposed footings 104, 105, each of the laterally disposed footings 104, 105 comprising a forward facing toe 106 and a rearward facing toe 107 that define an angular mounting surface 108 adapted to be mounted on a first ladder rung 109 of a ladder 110 to be secured to a support, such as a vehicle roof rack 1 1 1 . The laterally disposed footings 104, 105 are disposed beneath a respective laterally spaced section 1 12, 1 13 extending either side the proximal end 102.

[0038] The distal end 103 takes the form of an elongate tongue 1 14. A layer of compressible material 1 15 is provided on an underside of the elongate tongue 1 14 defining an engagement surface that engages with a second ladder rung

[0039] 1 16 of the ladder 1 10.

[0040] Referring also to Figures 3 and 4, the ladder clamp 100 further includes a strap

[0041] 1 17 provided with strengthening cables 118 extending along longitudinal edges thereof. As best seen in Figure 3, the strap 117 has a fixed end 119 secured to the clamp body 101. The fixed end 119 is secured to the clamp body 101 at a location between the first and second ladder rungs 109, 116.

[0042] The strap 117 extends from the fixed end 119 over a tensioning element 120 disposed on the clamp body 101 at a location towards the distal end 102 and then through an aperture 121 located in the clamp body 101. As best seen in Figure 4, the tensioning element 120 includes an eccentric cam 121 mounted for rotation between a first orientation “A” and a second orientation “B”. A polymeric surface 122 is provided on the eccentric cam 121 .

[0043] The distance between the strap 1 17 at the location of the aperture 121 and the ladder rung 109 is greater than the distance between the strap 1 17 and the ladder rung 109 on the opposing side, proximal end 102. This distance advantageously ensures that greater force is applied to the distal end 103 of the clamp body 101 preventing the clamp body 101 from rotating. As illustrated, a free end 123 of the strap 1 17 is in its final positioning after securing the ladder clamp 100 to the ladder 110 and vehicle roof rack 1 1 1 . To achieve this, the free end 123 is fed through an aperture 124 in a housing 125 disposed on the proximal end 102 of the clamp body 101 . The strap 117 is then fed through a strap retaining assembly comprising a pawl 126 mounted above the strap 1 17 and defining a first retaining surface 127 that engages an upperside of the strap 1 17, and a fixed block 128 disposed on the proximal end 102 of the clamp body 101 and defining a second retaining surface 129 that engages a corresponding under-side of the strap 1 17.The pawl 126 is biased such that the strap 1 17 can be passed through the first and second retaining surfaces 127, 129 in the feed direction but not back out through the opposite direction. The first and second retaining surfaces 127, 129 may be disengaged with the strap 1 17 by applying force to a distal end 130 of the pawl 126. After being fed through the strap retaining assembly, the strap 1 17 is guided by a guide 131 over the tensioning element 120 and fixed end 1 19 of the strap 1 17.

[0044] A U-shaped handle 132 is longitudinally mounted on an upper surface of the clamp body 101 . The handle is rotatable between a first orientation (not shown) in which it extends away from the upper surface of the clamp body 101 , downwards toward the distal end 103 of the clamp body 101 to a second orientation “D” (see Figure 4) in which it is disposed along the upper surface of the clamp body 101. The first orientation of the handle 132 corresponds with the first orientation A of the tensioning element 120 and the second orientation D of the handle 132 corresponds with the second orientation B of the tensioning element 120.

[0045] A lock 133 is optionally provided that includes a locking pin 134 that in a locked position (as illustrated) engages an under side of the distal end 130 of the pawl 126 preventing force applied to the distal end 130 from disengaging the first and second retaining surfaces 127, 129 from the strap 1 17.

[0046] Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term “comprising” is used in an inclusive sense and thus should be understood as meaning “including principally, but not necessarily solely”.

[0047] Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements.

[0048] It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.

Claims

CLAIMS1 . A ladder clamp for securing a ladder to a support structure, the ladder clamp comprising: a clamp body comprising a proximal end having at least two laterally disposed footings for mounting the proximal end on a first ladder rung and a distal end having an engagement surface for engaging the distal end with a second ladder rung longitudinally spaced from the first ladder rung; a strap having a fixed end secured to the clamp body at a position between said proximal end and said distal end, the strap extending over a tensioning element disposed on the clamp body at a location towards the distal end and then through an aperture located in the clamp body to a free end; a lever associated with said tensioning element and adapted to move said tensioning element between a first orientation in which it rests under said strap and a second orientation in which it applies increased tension on the strap in use; a strap retaining assembly disposed on said proximal end of said clamp body and comprising at least two opposed retaining surfaces through which the free end of said strap can be fed towards the distal end of the clamp body, thereby retaining said strap between said retaining surfaces.

2. A ladder clamp according to claim 1 , wherein each of said laterally disposed footings comprises a rearward facing toe and a forward facing toe that define an angular mounting surface adapted to be mounted on said first ladder rung.

3. A ladder clamp according to claim 2, wherein said clamp body comprises at least two laterally spaced sections extending either side the proximal end, said laterally disposed footings being disposed beneath a respective laterally spaced section.

4. A ladder clamp according to any one of the preceding claims, wherein said distal end comprises an elongate tongue extending from said strap retaining assembly.

5. A ladder clamp according to claim 4, wherein said elongate section comprises a layer of compressible material on an underside thereof defining said engagement surface.

6. A ladder clamp according to any one of the preceding claims, wherein said strap is reinforced, for example with one or more cables extending longitudinally within or on the strap.

7. A ladder clamp according to claim 6, wherein said strap includes a raised tab and / or an eyelet on the free end thereof.

8. A ladder clamp according to any one of the preceding claims, wherein said tensioning element comprises an eccentric cam mounted for rotation between said first orientation and said second orientation.

9. A ladder clamp according to any one of the preceding claims, wherein said lever comprises a U-shaped handle longitudinally mounted on an upper surface of said clamp body, the handle being rotatable between a first orientation in which it extends away from the upper surface of the clamp body, downwards toward the distal end of the clamp body to a second orientation in which it is disposed along the upper surface of the clamp body, wherein the first orientation of the handle corresponds with the first orientation of the tensioning element and the second orientation of the handle corresponds with the second orientation of the tensioning element.

10. A ladder clamp according to claim 9, further comprising a latch for securing the handle in said second orientation.1 1. A ladder clamp according to any one of the preceding claims, wherein said strap retaining assembly comprises a pawl mounted above said strap and defining a first retaining surface that engages an upper-side of the strap, and a fixed block disposed on said proximal end of said clamp body and defining a second retaining surface that engages a corresponding under-side of the strap.

12. A ladder clamp according to claim 11 , wherein an upper end of said pawl, disposed away from the first retaining surface, is moveable between a first orientation in which the first retaining surface engages the upper-side of the strap and a second orientation in which the first retaining surface disengages the strap thereby facilitating release of the strap from the strap retaining assembly.

13. A ladder clamp according to any one of the preceding claims, further comprising a lock for locking the strap retaining assembly, thereby preventing release of the strap from the strap retaining assembly.

14. A ladder clamp according to any one of the preceding claims, wherein said clamp body is formed from resilient material, such as a resilient thermoplastic material.

15. A ladder clamp according to any one of the preceding claims, further comprising a housing that houses the strap retaining assembly.

16. A ladder clamp according to any one of the preceding claims, wherein said support structure comprises a roof rack for a vehicle.

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