Cable tensioned rock guard for a trailer

A method and apparatus for guarding a cargo on a trailer without a peripheral sidewall against rock damage. The method involves tensioning a sheet of flexible non-supporting material to form a protective shield.

FIELD OF THE INVENTION

The present invention relates to a method for guarding a cargo on a trailer without a peripheral sidewall against rock damage and a rock guard for a trailer constructed in accordance with the teachings of the method.

BACKGROUND OF THE INVENTION

As a trailer is pulled along a road by a tow vehicle, rocks invariably are thrown up from the road surface. The rocks may originate from passing vehicles, or may originate from the tow vehicle. Some trailers have a peripheral sidewall that protects the cargo on the trailer from rock damage. With trailers that do not have a peripheral sidewall, the cargo is exposed and can sustain rock damage. For that reason, rock guards have been developed that mount onto trailers in order to protect cargo from rock damage. These rock guards are commonly positioned on trailers used to haul boats, motor vehicles, and snow mobiles; to name just a few of many applications.

SUMMARY OF THE INVENTION

The present invention relates to a method for guarding a cargo on a trailer without a peripheral sidewall against rock damage and a rock guard for a trailer constructed in accordance with the teachings of the method.

According to one aspect of the present invention there is provided a method of guarding a cargo on a trailer without a peripheral sidewall against rock damage. The method involves tensioning a sheet of flexible non-supporting material to form a protective shield.

According to another aspect of the present invention there is provided a rock guard for a trailer which is constructed in accordance with the teachings of the method. The rock guard includes at least one tensioning cable and at least one sheet of flexible non-supporting material having sufficient tensile strength to withstand tensioning. The sheet of material has means for accommodating the tensioning cable. At least one support member is provided having a first end and a second end. The first end is adapted to receive the tensioning cable. The second end is adapted for attachment to a trailer frame. At least one cable tensioning member is provided, whereby the sheet of material is tensioned with the tensioning cable to form a protective shield.

The invention, as described, involves tensioning a sheet of non-supporting material and positioning the sheet on a trailer to provide protection to the cargo from any rocks or debris rising from the road or the wheels of the towing vehicle.

Although beneficial results may be obtained through the use of the rock guard, as described above, it is desirable that the sheet of material be shaped to match the contours of the trailer. Even more beneficial results may, therefore, be obtained when at least one secondary support member is provided. The secondary supports help the sheet of material maintain a desired shape. Each secondary support has a first end and a second end. The first end is adapted to receive the tensioning cable. The second end is adapted for attachment to a trailer frame. It assists in promoting the desired shaping of the protective shield when the secondary support member is in an angularly offset orientation.

Although beneficial results may be obtained through the use of the invention, as described above, boat trailers have a front mounted winch that is used to pull a boat out of the water and onto the trailer. It is, therefore, preferable that the protective shield be removable in order to allow unfettered access to the front of the trailer when launching or recovering the boat. Even more beneficial results may, therefore, be obtained when the second end of each support member has a detachable trailer frame attachment bracket. This allows the attachment bracket to be attached to the trailer frame, and the support member to be attached to and detached from the attachment bracket, as required. For this purpose it is preferred that the attachment bracket have a male coupling and the support member a female coupling. It has been found that it is most convenient when the secondary support members are positioned in pockets in the sheet of material. The tensioning cable can be extended through an aperture at the first end of the secondary support member to prevent the secondary support member from being withdrawn from the pocket in the sheet of material.

There are various cable tensioning mechanisms that can be used with the rock guard, as descried above. Beneficial results have been obtained through the use of a cable tensioning member that has a pivotally mounting cam member. The tensioning cable can be tensioned by moving the cam member about a pivot.

Although beneficial results may be obtained through the use of the invention, as described above, even more beneficial results can be obtained when the sheet of non-supporting material has a plurality of secondary attachment straps by which an edge of the sheet adjacent the frame of the trailer can be secured to the trailer, whereby the non-supporting material can be tensioned between the straps and the tensioning cable.

Although beneficial results may be obtained through the use of the invention, as described above, even more beneficial results can be obtained when the sheet of non-supporting material is divided into two sheets of non-supporting material, each of the two sheets being a mirror image of the other, one of the two sheets being securable at one side of the trailer and another of the two sheets being securable at another side of the trailer, the two sheets thereby severing to protect a load on the trailer from rock chips. The two sheets allow more ready access to the primary support member without reducing the level of protection afforded by the invention.

Although beneficial results may be obtained through the use of the invention, as described above, even more beneficial results can be obtained when the tensioning cable has a first end and a second end, both of the first end and the second end having attachment loops by which the tensioning cable is detachably securable to each of the support member and one of the cable tensioning members.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The preferred embodiment, a rock guard for a trailer generally identified by reference numeral 10 , will now be described with reference to FIGS. 1 through 13 .

Referring to FIGS. 2 and 3 , rock guard 10 is mountable on a trailer 12 that does not have an enclosed peripheral sidewall, such as is used to transport a boat 13 . Trailer 12 has a hitch end 60 , a loading end 62 , and a pair of opposed sides 64 . A preferred embodiment of rock guard 10 includes a pair of tensioning cables 14 , a pair of sheets of non-supporting material 20 , each of pair of sheets 20 being a mirror image of the other, a primary support member 34 , a pair of cable tensioning members 36 , and a pair of secondary support members 38 .

Referring to FIG. 1 , each tensioning cable 14 has an attachment loop 15 at each of a first end 16 and a second end 18 . Each of pair of sheets 20 has sufficient tensile strength to withstand tensioning. Each of pair of sheets 20 has a first portion 19 , a second portion 21 and a peripheral edge 22 . Peripheral edge 22 has a first portion 24 , a second portion 26 , a third portion 28 , and a fourth portion 29 . First portion 24 of peripheral edge 22 has a cable sleeve 30 with a channel 32 for accommodating tensioning cable 14 . Cable 14 emerges from channel 32 through eyelets 33 .

Primary support member 34 has a first end 40 and a second end 42 . Referring to FIG. 10 , first end 40 of primary support member 34 has an hook attachment 44 for loop 15 at first end 16 of tensioning cable 14 . Referring to FIG. 7 , second end 42 of primary support member 34 is in the form of a female coupling 43 which detachably receives a male member 45 of a primary trailer frame attachment bracket 46 . Referring to FIG. 9 , attachment bracket 46 is secured to a frame 52 at hitch end 60 of trailer 12 in a male-female engagement. Referring to FIG. 4 , primary attachment bracket 46 is positioned on frame 52 between hitch end 60 and a winch 72 secured by a post 74 to frame 52 . Winch 72 is used for loading boat 13 on to trailer 12 , as illustrated in FIGS. 2 and 3 .

Referring to FIGS. 12 and 13 , each cable tensioning member 36 has a detachable cam 48 pivotally mounted by a pivot rod 49 extending from each of opposed sides 51 of cam 48 to a cam support 50 . Referring to FIG. 6 , cam support 50 is secured to frame 52 at one of opposed sides 64 of trailer 12 . Referring to FIG. 12 , cam 48 is pivotally moveable between a released position, shown as dotted lines 100 , and a tensioned position, shown as solid lines 102 . Referring to FIG. 1 , when cam 48 is in the released position 100 , cable 14 is not tensioned, and first end 16 of cable 14 is releasable from primary support member 34 . When cam 48 is in the tensioned position 102 , cable 14 is securely tensioned between cable tensioning member 36 and primary support member 34 .

Referring to FIG. 5 , each secondary support member 38 has a first end 54 and a second end 56 . Referring to FIG. 1 , each secondary support member 38 is housed within a sleeve or pocket 58 . Pocket 58 has an opening 59 adjacent second portion 26 of peripheral edge 22 of sheet 20 from which second end 56 of secondary support member 38 extends. Referring to FIG. 11 , cable 14 passes through a passage 66 at first end 54 of each secondary support 38 . Referring to FIG. 5 , second end 56 of secondary support member 38 is in the form of a female coupling 67 that detachably receives in a male-female engagement a male member 68 of a secondary trailer frame attachment bracket 70 . Referring to FIGS. 1 and 8 , secondary trailer frame attachment bracket 70 is secured to frame 52 at one of opposed sides 64 of trailer 12 . When secondary trailer frame attachment bracket 70 is secured to frame 52 , male member 68 is outwardly inclined, thereby affecting the orientation of secondary support member 38 .

First straps 76 are secured to second edge 26 adjacent third edge 28 of one of pair of sheets 20 . First straps 76 extend under frame 52 of trailer 12 and are detachably securable to second edge 26 of another of pair of sheets 20 , thereby tensioning second edge 26 of each of pair of sheets 20 . Second straps 77 extend from fourth portion 29 adjacent each of first portion 24 and second portion 26 of peripheral edge 22 of each of sheets 20 . Second straps 77 loop around cam support 50 to tension second portion 21 of sheets 20 between cam support 50 and secondary support member 38 .

The method of use of rock guard 10 will not be described with reference to FIGS. 1 through 13 . Rock guard 10 as described above is provided. Referring to FIG. 4 , primary trailer frame attachment bracket 46 is secured at hitch end 60 of trailer 12 . One each of secondary trailer frame attachment brackets 70 and cam support 50 are secured to frame 52 at each of opposed sides 64 of trailer 12 . Winch 72 , illustrated in FIG. 1 , is used to load boat 13 onto trailer 12 . When boat 13 is secured in place on trailer 12 , as illustrated in FIGS. 2 and 3 , second end 42 of primary support member 34 is mounted on male member 45 of trailer frame attachment bracket 46 , illustrated in FIG. 7 . Second end 54 of each of secondary supports 38 carrying one each of cables 14 and sheets 20 is mounted on one of outwardly inclined trailer frame attachment brackets 70 , illustrated in FIG. 5 . Referring to FIG. 1 , each of sheets 20 is extended between primary support member 34 and cable tensioning member 36 . Loop 15 at first end 16 of each of cables 14 is secured to first end 40 of primary support member 34 as illustrated in FIG. 10 . First straps 76 are secured under frame 52 of trailer 12 between second edges 26 of each of sheets 20 as illustrated in FIG. 1 . Referring to FIG. 6 , each of cams 48 is mounted on one of cam supports 50 . Second straps 77 are looped about cam support 50 . Loop 15 at second end 18 of cable 14 engages cam 48 of cable tensioning member 36 as illustrated in FIG. 6 . Cam 48 moves pivotally to tension cable 14 between cable tensioning member 36 and primary support member 34 . Referring to FIG. 1 , tensioned cable 14 maintains first edge 24 of sheet 20 in a taught and elevated position, and prevents secondary support 38 from inadvertently detaching from secondary trailer frame attachment bracket 70 . Rock guard 10 so installed prevents rocks or other debris from striking boat 13 while trailer 12 is being towed.

The method of unloading boat 13 from trailer 12 and storing rock guard 10 will now be described. Cam 48 is moved pivotally to release tension in cable 14 . Loops 15 are detached from primary support member 34 and tensioning member 36 . Straps 76 are detached from second edges 26 of each of sheets 20 . Primary support member 34 is detached from primary trailer frame attachment bracket 46 and secondary support members 38 are each detached from secondary trailer frame attachment brackets 70 . Rock guard 10 is then out of the way as boat 13 is unloaded from trailer 12 . Sheets 20 containing secondary support members 38 can then be rolled up into a small bundle and stored with primary support member 34 and cams 48 and stored in a storage bag.