DEVICE FOR SECURING A LOAD BEARING ELEMENT

Abstract: A device for removably attaching a load-bearing bar (2) to passenger car roof rails (1) comprises a pair of legs (4) freely swingably hooked (8) into a slot in the bottom of said bar, and feet (5) extending from the bottom of said legs under the rail when the device is slid into attachment position. For forcing the legs apart and thus the feet into contact with the underside of the rail and thereby establishing balanced three-point gripping attachment to the rail (1), a rod (7), having oppositely threaded portions passing through individual nuts (6) rotatably held in respective legs (4), is rotated manually by means of knobs (3) mounted at the ends of the rod (7).

Description: Title: Device for securing a load bearing element The present invention applies to a car luggage rack or load-carrying bars, intended for easily removable mounting on a pair permanently mounted rails running longitudinally along either side of the car roof. In particular it relates to a device for securing a load bearing element onto a roof rail disposed longitudinally on a vehicle. For carrying loads, commonly a pair of transverse load-carrying bars are temporarily secured in spaced relation to each other onto the permanently mounted longitudinal rails on the roof of modern passenger cars. Other types of load carriers such as ski-racks, ski-boxes, bike racks, board racks etc. are also designed to be temporarily secured onto the permanently mounted longitudinal roof rails. The demands placed on the devices for securing these load carriers to the rails include very secure mounting when the load is subjected to wind, air resistance, bumpy road conditions etc., ease of attachment, ease of adjustment to different rail spacings, adaptability to different rail shapes and streamlined design. One attempt to meet the above mentioned demands is described in Swedish Patent Specification 9603296-6 (Publication No. 507 371). A transverse load carrying bar is clamped onto the respective rail by means of a pair of opposing jaws which can be drawn together around the rail (or separated) by means of a screw, mounted within the profiled load carrying bar. The screw has one end rotatably but non- displacably joined to the outer jaw. The inner jaw moves towards or away from the outer jaw as the upper extension of the inner jaw moves axially along the screw threads as the screw is turned, in this case by means of a driver inserted in form- fitting relation into the interior of the screw. The driver has a handle which can be partially inserted into the open end of the profiled load carrying bar after the jaws are tightly clamped around the rail to prevent loosening rotation of the screw and to form the end of the load carrying bar. The outer jaw has a V-shaped inner surface to contact both the underside and the outer side surface of the rail. The inner jaw, which has a V-shaped clamping surface to contact both the topside and the inner side surface of the rail, telescopes relative to its screw-engaging upper extension in order to assume a proper clamping position relative the outer jaw and the rail. Despite the opposing V-shapes and the telescoping connection between the inner jaw and the adjustment nut, friction or jamming may result in a two-point horizontal griping of the rail by the jaws, instead of a fully secure three-point, top-bottom fix- ing of the attachment device on the rail. If there should only be a two-point clamping of the rail between the jaws, the attachment may feel secure even when loaded before the start of a transport, but this two-point horizontal grip, when subjected to extreme dynamic loads due to bumpy roads or wind resistance, may fail, loosening the entire grip. The telescoping connection between the inner jaw and the adjust- ment nut may be prone to jamming, and in any case it is a compKcated construction increasing the cost of the device. In the above mentioned known device, one leg of the V-shaped inner surface of the inner jaw rests on the rail when mounted. This, together with the fact that the outer jaw is disposed between the inner jaw and the transverse bar increases greatly the height of the transverse bar above the rails, which can be of great disadvantage when attempting to achieve a streamlined load with lateral stability. In order to solve these problems there is suggested a device of the type described above by way of introduction, which has the features recited in the characterizing clause of the attached Claim 1. The securing device according to the present invention enables the load bearing element to rest directly on the rail, in which case it forms one of the three points of the stable three-point grip. Since the pair of legs is freely swingably depending from the the load bearing element, a stable three-point grip will always be established when the legs are forced apart when the feet are in position under die rail. An inferior, less secure two-point grip cannot be established with the device according to the present invention. The invention as claimed is also much less complicated and therefore less expensive to manufacture and less prone to failure than previously known devices. The present innovation will now be described with reference to a non-limiting example with reference to the accompanying drawings of which: Fig. 1 shows schematically in perspective one embodiment of the present invention with certain dimension exaggerated or diminished for illustrative purposes, Fig. 2(a) shows an end view in cross section of a similar embodiment as in Fig. 1, where the legs have been forced fully apart, and Fig. 2(b) shows the same view as in Fig. 2(a) but where the legs are in their release position. As best can be seen in Fig. 1, in which the dimensions of the legs and the threaded rod 7 are exaggerated for illustrative purposes, the load carrying element 2, which in this case is a profiled bar with a slot running along its underside, is laid transversely across the two roof rails 1 (only one shown here). Either the roof rail 1 or the underside of the bar 2 may be provided with some sort of protective or elastic coating to protect the upper surface of the rails. A pair of legs 4 is hooked 8 into the slot running along the bottom of the bar 2, as best can be seen in Fig. 2. They are freely swingable in this slot. This is an important feature for establishing a balanced three-point clamping of the ' rail. Other constructions where the legs 4 are freely piv- otable in a plane parallel to the rail will be readily apparent to the person skilled in the art. The end of each leg 4 is provided with a foot 5 extending inwardly under the rail 1. The legs 4 and feet 5 are covered for protection by a plastic shield which is not shown here. Each leg 4 has a solid cylindrical nut 6 which is freely rotatable in a cylindrical cavity in the respective leg. A threaded rod 7 is screwed into both nuts 6 as can be seen in the figures. The rod 7 has two oppositely pitched portions so that as the screw is rotated by means of the two knobs 3 the legs will move in opposite direc- tions, either towards each other or apart. Each leg 4 is provided with slots 4a and 4b for passage of the threaded rod through the leg at various positions as the legs are moved apart or together, and the cylindrical nuts 6 rotate in their cylinders in the legs as the legs are moved. For attachment of the load bearing bar 2 to the rail the procedure is as follows: Hopefully, the legs at each end of the bar are in the release position shown in Fig. 2(b), otherwise the threaded rod 7 must be rotated until the release position is assumed, the entire device comprising the legs 4, the rod 7 and the knobs 3 is pulled outwardly whereby the hooked ends 8 of the legs 4 slide outwardly in the slot in the bar 2. A stop member or an end piece (not shown) is provided to prevent the device from being pulled out of the slot. With the two attachment devices spaced so that the distance between the facing ends of the feet 5 is greater than the distance between the outer sides of the two parallel side roof rails 1, the bar with the attach- ment devices is laid across the rails. The attachment devices are then pushed inwards along the slots until the feet 5 extend under the respective rail 1, in this embodiment, under the entire width of the respective rail 1. The knobs 3, two in number here in order to apply the force of two hands if needed are then used to rotate the threaded rod 7 until the feet 5 press against the underside of the rail 1. Should the attachment device be unevenly disposed for some reason, so that one foot 5 reaches the underside of the rail before the other foot 5. then the former foot will stop and the other foot will continue its movement towards the underside of the rail, at twice the previous rate per rotation of the knobs. Due the fact that the legs 4 are freely swingable from the bar 2, via their hook ends 8, the device will assume a bal- anced three-point grip against the top and bottom surfaces of the rail. This will occur regardless of uneven placement of the bar, uneven surfaces on the rail or place- ment of the bar near the mounting posts of the roof rails. The load bearing bars can be rapidly switched, without any adaptation, from one rail-equipped car to another car having rails of completely different shape and dimensions, and still achieve the same secure three-point grip. Although the illustrative embodiment relates to an attachment device mounted on a load-carrying bar, the present invention may just as easily be applied to other types of load carrying elements such as frames for carrying bicycles, surfboards, ski- racks, skiboxes etc. The person skilled in the art will recognize that the threaded rod with oppositely pitched portions, used in the embodiment illustrated above, could be replaced with a threaded rod of a single orientation but where one of the cylindrical nuts is replaced by a bushing which fixes the rod axially but not rotationally. The person skilled in the art will also realize that the feet 5 fixed at the ends of the legs 4 may, in some embodiments only extend partially under the width of the rail 1, provided the necessary three-point grip is achieved. The person skilled in the art will also understand that the means for forcing the legs apart need not necessarily be a threaded rod but may just as well be an an excenter cam lever mechanism, a turnbuckle or bottle screw arrangement, where the screws threaded into the ends of the turnbuckle or bottle are each pivotally attached to a respective leg and force the legs apart as the turnbuckle is rotated.

Claims: CLAIMS 1. Device for securing a load bearing element (2) onto a roof rail (1) disposed longitudinally on a vehicle, characterized by: (a) a pair of legs (4) which depend from said load bearing element (2) and are freely swingable in a plane parallel to and adjacent said rail (1) when said load bearing element (2) is in its position for mounting on said rail (1), each of said legs (4) having a foot (5) extending, from its end opposite said load bearing element, under said rail (1) when the load bearing element is in its position for mounting; (b) means (7) for forcing said pair of legs apart until said feet come into contact with said rail and for maintaining said contact 2. Device according to Claim 1, characterized in that said load bearing element is a bar which extends, when in its mounting position, transversely between two parallel roof rails. 3. Device according to Claim 1 or 2, characterized in that the means for forcing said pair of legs apart is a threaded rod (7) passing through both legs. 4. Device according to Claim 3, characterized in that said threaded rod (7) has two oppositely pitched portions screwed into respective nuts (6) held in respective legs (4). 5. Device according to Claim 3 or 4, characterized by knobs (3) fixedly mounted at the extreme ends of the threaded rod (7). 6. Device according to one of the preceding claims, characterized said pair of legs (4) are freely swingable in a plane parallel to and adjacent said rail (1) by means of hooked ends extending into a longitudinal slot in the bottom of the load bear- ing element.

Inventors: ELDERED KJELL, HAGSTRAND OLOF, HULT LARS, ROSQVIST OLLE, ELDERED, KJELL, HAGSTRAND, OLOF, HULT, LARS, ROSQVIST, OLLE
Applicants: CALIX AB, ELDERED KJELL, HAGSTRAND OLOF, HULT LARS, ROSQVIST OLLE, ELDERED, KJELL, HAGSTRAND, OLOF, HULT, LARS, ROSQVIST, OLLE
Application year: 2000
Main classification: B60R9
IPC codes: B60R9