WO2014018283A1 - Ladder clamping apparatus for vehicle roof rack - Google Patents

Description

LADDER CLAMPING APPARATUS FOR VEHICLE ROOF RACK BACKGROUND OF THE INVENTION

I· Cross Reference to Related Application:

This application claims priority to U.S. provisional application, Serial No, 61 /674,498, filed July 23, 2012, the contents of which are hereby incorporated by reference.

II- Fie!d of the Invention:

This invention relates generally to roof racks for work vehicles and more particularly to a clamping apparatus for releasably securing a workman's ladder to the roof rack structure.

111. Discussion of the Prior Art:

In published PCT Application WO 2009/126286 there is provided a detailed description of a vehicle roof rack used for transporting loads on the vehicle roof. The contents of that published application are hereby incorporated by reference and form part of the present application's disclosure.

That application describes an extremely strong, yet lightweight and easy to assemble, roof rack for motor vehicles and is realized using extruded aluminum tubing to create side members and crossbars for joining the side members to one another across the width dimension of a vehicle's roof. Each side member comprises a pair of elongated rails that are clamped together by a series of clamps that cooperate with attachment spines integrally formed with the rails. Attachment flanges forming a part of the extrusion on one rail on each side member facilitates the attachment of the crossbar members thereto. In this way, no welding is required in fabricating and assembling the roof rack structure.

A roof rack of the type described can be used to transport ladders of various types, e.g. step ladders and extension ladders, and so-called buogee cords or ropes may used to secure a ladder to the roof rack structure. The present invention comprises an attachment for a roof rack like that described in the aforereferenced PCT application that can be used to facilitate placement of a ladder onto the vehicle roof rack and to rapidly secure the ladder in place without the need to apply bungee cords or ropes to accomplish this end.

In a co-pending patent application serial no, 12/71 ,573, filed March 8, 2010 (published application US 2011/0214944 Al), there is described an earlier invention of applicant namely, a ladder rack for work vehicles that comprises a pair of side rails held in parallel, spaced relating by a pair of crossbars. Extending between the crossbars is at least one hook bar on which is fixedly attached a ladder clamping arm, A latch mechanism is affixed to a rearmost crossbar for re!easably securing ladders on the rack. It comprises a crank on a rotatable shaft held by brackets affixed to the rear crossbar for rotation about an axis parallel to the crossbars, A rear ladder clamping arm is affixed to the rotatable shaft and aligned wi h the front clamping arm affixed to the hook bar. The front and rear hooks are adapted to engage spaced ladder mngs of a ladder being carried on the vehicle roof rack. The present Invention is deemed to be an improvement over the invention described and claimed in the above-referenced pending U.S. published application.

SUMMARY OF THE INVENTION

The present invention comprises a clamping arrangement having a pair of longitudinally spaced clamping arms designed to engage a pair of spaced-apart ladder steps or rungs of a ladder placed horizontally on the crossbar members of the roof rack. The clamping arms are linked to one another by a longitudinally extending rod that is jo maled for rotation in rod supports that clamp to spaced-apart ones of the roof rack's crossbar members. The rod has a crank arm affixed at a rear end thereof to facilitate manual rotation of the rod.

Also clamped to spaced-apart crossbar members of the roof rack and extending parallel to said crossbar members are roiatably mounted actuator rods on which the clamping arms are attached. The rods to which the clamping arms are affixed also support a pair of rollers. Extending between the clamping arms and the longitudinally extending rod is a two-piece articulated linkage.

When the longitudinally extending rod is manually rotated, the actuating rods thai extend parallel to the crossbar members and transverse to the longitudinally extending rod are made to rotate so as to simultaneously spin the front and rear ladder clamping arms 90^e from a lowered position, generally parallel to the vehicle's roof, to a raised position generally perpendicular thereto. When in the raised position, the front and rear ladder clamping arms are adapted to engage spaced apart ones of ladder steps or rungs, preventing movement of the ladder relative to the roof rack during sudden starts and stops of the vehicle on which the roof rack is mounted. When the ladder clamping arms are fully raised, the two-piece articulated links employed form a rigid brace preventing bending of the ladder clamping amis as a result of inertia! forces acting on the clamped ladder.

The rollers mounted on the parallel extending actuator rods are positioned such that when the ladder clamping arms are in their lowered position, the rollers project upward above the level of the crossbar members, thereby providing rolling support for the parallel side rails of a ladder as a ladder is being either loaded onto or removed from the roof rack. When the ladder clamping arms are in their raised, ladder clamping position, the rollers are retracted such that the ladder rests upon the stationary crossbars of the roof rack.

DESCRIPTION OF THE DRAWINGS

The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment, especially when considered in conjunction with the

!?.f accompanying drawings in which like numerals in the several views refer to

corresponding parts.

Figure 1 is a perspective view of a roof rack incorporating the ladder clamping apparatus of the present invention with the clamping arms fiilly erect;

Figure 2 is a view like Figure I with the clamping arms only slightly retracted;

Figure 3 is a view like Figure 2 with the clamping arms further retracted;

Figure 4 is a view like Figure 3 with the clamping arms fully retracted;

Figure 5 is a partial rear view with the actuation crank in a position causing the clamping amis to be fully extended;

Figure 6 is a partial rear view like Figure 5 with the actuating crank rotated slightly clockwise; Figure 7 is a view like Figure 6 with the actuating crank rotated further clockwise;

Figure 8 is a view like Figure 7 with the actuating crank rotated fully clockwise such that the clamping arms are fully lowered;

Figure 9 is an enlarged partial perspective view from the rear showing the clamping arm in its fully erect position;

Figure 10 is a view like Figure 9 but with the damping arm on its way down to a fully retracted position; and

Figure S ! is a view like Figure 10, but with the clamping arm fully retracted, DESCRIPTION OF THE PREFERRED EMBODIMENT

This description of the preferred embodiments is intended lo be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as "lower", "upper", "horizontal", "vertical", "above", "below", "up", "down", "top" and "bottom" as well as derivatives thereof (e.g., "horizontally", "downwardly",

"upwardly", etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as "connected", "connecting", "attached", "attaching", "join" and "joining" are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressively described otherwise.

A vehicle roof rack on which the present invention finds use is illustrated in Figure S of the drawings and in Figure 1 of the published PCT application that is incorporated by reference herein. It includes right and left side rail assemblies 10, 1 1 heid in parallel, spaced apart relation by a plurality of transversely extending crossbar members 13, 15, 17, 19, 21. The crossbar members clamp to the extrusions comprising the left and right side rails in the manner described in the PCT application mentioned.

In Implementing the novel ladder clamping apparatus of the present invention. a journal bracket 14 incorporating a nylon sleeve bearing 16 is clamped to the frontmost crossbar member 13 arid joumaied for rotation therein is a longitudinally extending rigid rod 18 that extends parallel to the left and right side rail assemblies 10, 1 1. The opposite end of the rod ! 8 is joumaied in a bracket 20 (Figure 5) that clamps to the rearmost crossbar member 21 , Similar brackets may be provided on one or more of the crossbar members ! 5, 17, 1 intermediate the front and rear ones to provide additional support for the rod 18·

With continued reference to Figure I, a further, transversely extending actuator rod 22 is joumaied for rotation by brackets 24 that clamp onto a crossbar member 35. Affixed to rod 22 is a front ladder clamping arm 26. The manner in which the front ladder clamping arm 26 is affixed to the rod 22 will be more fully explained with the aid of Figure 9 showing an enlarged, substantially identical assembly connected to the crossbar member 19,

Extending between the ladder clamping arm 26 and the longitudinal rod 18 is an articulated linkage indicated generally by numeral 28. It comprises a pair of links 30, 32 having a ball-joint coupling the two links together at 34. A ball joint also joins link 32 to the ladder clamping arm 26 in a manner to be explained more fully below. Link 30 Is rigidly affixed to a clamp 35 fastened on the elongated longitudinally extending rod 18.

Referring now to Figure 9, a substantially identical arrangement that is used to clamp the front clamping arm 26 to the longitudinally extending rod 18 is seen as being secured to the crossbar member 1 which is inwardly adjacent to the rearmost crossbar member 21. Again, a pair of spaced-apart brackets 24' clamp So clamping ridges on the undersurface of the crossbar member 1 and a transversely extending rod 22' is joumaied for rotation in the brackets 24'. A clamp 23 is fitted about the rod 22' to tightly engage same and affixed to the clamp 23 is a slotted plate 25 to which the clamping arm 26' is affixed by bolts 29 (Fig. 6) passing through the slot 27 of the plate 25. In this way, the ladder clamping arm 26' is height adjustable over a limited range.

Referring momentarily again to Figure 3, it is to be noted that a pair of rollers 38, 40 is mounted on the front transverse actuator rod 22 in an actuator offset relation so as to rotate about a separate axis offset from that of the front transverse actuator rod 22. Figure 9 shows a similar pair of rollers 38', 40' for the rear transverse actuator rod 22',

A crank 42 is affixed to the rear end of the longitudinally extending rod 18,

By pushing on the crank, the rod 18 is made to rotate in its journal brackets 14, 14', and in doing so, rotation is imparted through the articulated linkages 28, 28' to the actuator rods 22, 22'. As a result, the pair of ladder clamping arms 26, 26' is made to move between a generally horizontal position at a level be!ow that of the crossbar members and a generally vertical position as in Figures I , 5 and 9. When the ladder clamping arms are in their vertical position, the links 30, 32 and 30', 32' become rectilinear with respect to one another and act as a stiffening brace between the arms 26, 26' and the rod 18 to prevent deflection of the ladder clamping arms due to inertia forces acting on a ladder as it is being transported.

Referring once more to Figure 1 , operatively coupled to the crank handle 42 used to rotate the rod 18 is an "over-center" mechanism that positively places the ladder clamping arms in their full extended and fully retracted positions. Specifically, the clamp device 44 that joins the crank 42 to the end of the longitudinally extending rod 18 includes a clevis 46 in which a pin 48 is pivotal ly joined. Surrounding the pin 48 is a compression spring 50 that acts against a stop member 52, that is clamped to crossbar member 21 at 54 and where the pin 48 extends through an aperture (not shown) formed through the stop member 32. The end of the spring 50 abuts solid material of the stop member 52 surrounding the aperture so that only an end portion of the pin 48 passes through the aperture. The pin serves to keep the spring from bending as it is compressed. When the crank 42 is turned in a clockwise direction as shown in Figures 5-8, past center to lower the ladder clamping arms 26, 26' to their horizontal disposition, the spring force urges the crank handle 42 further in the clockwise direction to a positive stop position where the ladder clamping amis are fully retracted. Likewise, when the crank handle 42 is now rotated back

counterclockwise past a center position, the spring 50 and pin 48 assume an angle urging the crank in the counterclockwise direction to a positive stop position where the ladder clamping arms are fully erect.

When the arms 26, 26' are lowered to the horizontal disposition, the rollers 38, 40 and 38', 40' are at an elevation above the level of the crossbar members and the 5 lateral spacing between the rollers 3§, 40 and between 38 40' are such that they will align with the rails of extension or step ladders, allowing a person to easily advance a ladder onto the roof rack due to the reduced friction afforded by the rollers. Then, when the operating crank is turned to raise the ladder clamping arms to engage a spaced pair of ladder rungs and thereby capture the ladder, the rollers will drop down

10 below the level of the crossbar members such that the ladder that has been loaded to rest upon the crossbar members rather than on the rollers.

Referring to Figures 8 and 9, when the crank arm 42 is rotated counterclockwise from the position shown in Figure 8 to that shown in Figure 9, an aperture 43 in the crank ami 42 becomes aligned with the aperture 53 in the stop

I S member 52 allowing the hasp of a padlock to be inserted through the aligned

apertures, thereby locking the ladder clamping arms 26, 26' in their elevated disposition and preventing unauthorized removal of any ladder engaged by the clamping arms.

This invention has been described herein in considerable detail in order to 0 comply with the patent statutes and to provide those skilled In the art with the

information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and trial various modifications, both as to the equipment and operating procedures, can be 3 accomplished without departing from the scope of the invention itsel

What is claimed is:

Claims

S , A ladder clamping device for a vehicle roof rack, the roof rack comprising left and right side rail assemblies held in parallel, spaced-apart relation by a plurality of crossbar members arranged in parallel, spaced-apart relation between the left and right side rail assemblies, the ladder clamping device comprising:

(a) an elongated rod adapted to extend parallel to the left and right side rail assemblies and to he journaled for rotation beiweers front and rear ones of the lurality of crossbar members;

(b) first and second actuator rods adapted to be clamped to selected ones of the crossbar members so as to be ro atable about axes offset and parallel to the crossbar member to which it is to be clamped;

(c) a ladder clamping arm affixed to each of the first and second actuator rods; and

(d) articulated linkages coupled between the clamping arms and the elongated rod such that rotation of the elongated rod over a predetermined arc simultaneously moves the ladder clamping arms between a vertical and a horizontal disposition, the clamping arms adapted to engage ladder rungs of a Sadder resting on the crossbar members when in their vertical disposition.

2. The ladder clamping device of claim I and further including a pair of rollers mounted on each of the first and second actuator rods.

3. The ladder clamping device of claim 2 wherein the pair of rollers are mounted such that when the ladder clamping arms are horizontally oriented, the rollers are elevated relative to the crossbar members and when the Sadder clamping arms are vertical, the rollers are retracted relative to the crossbar members when the ladder clamping device is mounted on the vehicle roof rack.

4. The ladder clamping device of claim I and further including a crank arm affixed to the elongated rod.

5. The ladder clamping device of claim 4 and further including an over- center device coupled to the crank arm.

6. The ladder clamping device of claim 5 wherein the over-center device comprises a pin member pivotally joined to the crank ami, the pin member extending through an aperture in an adjacently positioned stop member; and a compression coiled spring surrounding the pin member and abutting the stop member.

7. The ladder clamping device of claim 1 wherein the articulated linkages each comprise a metal strap clamped at a first end to the elongated rod; a metal rod pivoia!iy coupled at a first erid to the ladder clamping arm and a ball joint connecting a second end of the metal strap to a second end of the mefa! rod.

8. The ladder clamping device of claim 2 wherein the pair of rollers on each of the first and second actuator rods are spaced apart by a distance corresponding to a spacing between longitudinal rails of a ladder to be transported.

9. In combination with a vehicle roof rack for transporting a ladder, a ladder clamping device comprising:

(a) a pair of ladder clamping arms adapted to engage a pair of spaeed-apart ladder rungs of a ladder when resting on the vehicle roof rack; and

(b) means mounted on the vehicle roof rack for simultaneously rotating the pair of ladder clamping arms between a rung engaging position and a rung disengaged position.

10. The combination of claim 9 wherein the means mounted on the vehicle roof rack for simultaneously rotating the pair of ladder clamping arms comprises:

(a) a longitudinally extending, elongaied rod joumaled for rotation in brackets affixed at opposed ends of said roof rack;

(b) a pair of transversely extending actuator rods rotatab!y joined to and longitudinally offset from a selected pair of crossbar members of the roof rack;

(c) an articulated linkage operative!y coupled between the elongated rod and said ladder clamping arms where said clamping arms are joined to the pair of transversely extending actuator rods.

1 1. The combination of claim 9 and further including:

(a) rollers operatively coupled to the ladder clamping device and simultaneously movable with the pair of Sadder clamping arms for selectively being engaged and disengaged with respect to side rails of ladders being loaded onto the vehicle roof rack.

12. The combination of claim 10 and further including:

(a) a hand crank member affixed to the elongated rod to facilitate rotation thereof; and

(b) an over-center mechanism operatively coupled to the hand crank member.

13. The combination of claim 12 wherein the over-center mechanism includes:

(a) a pin member pivotally secured to the hand crank member, the pin member extending through an aperture in a bracket affixed to the ladder roof rack, and

(b) a helical compression spring surrounding the pin with an end of the spring abutting the bracket around its aperture.

14. A ladder rack assembly mouniab!e on a vehicle roof comprising:

(a) a left and a right side rail assembly,

(b) a plurality oflongitudinafly spaced, transversely extending crossbar members clamped at opposed ends to the left and right side rail assemblies;

(c) an elongated, longitudinally extending rod journated for rotation in brackets affixed to front and rear ones of the plurality of cross bar members;

(d) a pair of transversely extending actuator rods jo maled for rotation in brackets clamped to the crossbar members that are inwardly adjacent to the front and rear ones of the plurality of crossbar members;

(e) a front ladder clamping arm affixed to the transversely extending actuator rod clamped to the crossbar member that is inwardly adjacent the front one of the plurality of crossbar members and a rear ladder clamping arm affixed to the transversely extending actuator rod clamped to the crossbar member that is inwardly adjacent the rear one of the plurality of crossbar members;

(f) a first articulated linkage coupling the front ladder clamping arm to the longitudinally extending rod and a second articulated linkage coupling the rear ladder clamping arm to the longitudinally extending rod whereby rotating of the longitudinally extending rod simultaneously moves the front and rear ladder damping arms between a vertical and a horizontal disposition relative to the plurality of crossbar members.

15. The ladder rack assembly of claim 14 and further including a pair of rollers clamped to and rotatable about axes that are parallel to the pair of transversely extending actuator rods, the axes being arranged such that when the damping arms are in the horizontal disposition, the rollers are elevated relative to the plurality of crossbar members and when the Sadder clamping amis are in the vertical disposition, the rollers are recessed below the plurality of crossbar members,

16. The ladder rack assembly of claim 14 wherein each of the first and second articulated linkages comprises:

(a) a metal strip rigidly affixed at one end to the longitudinally extending rod and joined at an opposite end by a first ball joint to a first end of a metal rod whose second end is joined to an associated ladder clamping arm by a second ball joint.

17. The ladder rack assembly of claim 16 wherein when the ladder clamping arms are in the vertical disposition, the metal strip and the metal rod are rectilinear.

18. The ladder rack assembly of claim 14 and further including a crank arm clamped to the longitudinally extending rod to facilitate rotation thereof and art over-center mechanism operatively coupled to the crank arm and the rear one of the plurality of crossbar members.