GB2344789A

GB2344789A - A convertible vehicle roof box

Info

Publication number: GB2344789A
Application number: GB9827751A
Authority: GB
Inventors: Anthony Wilkes
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-12-16
Filing date: 1998-12-16
Publication date: 2000-06-21
Anticipated expiration: 2018-12-16
Also published as: GB2344789B; GB9827751D0

Abstract

A vehicle roof box (2) is convertible into a box trailer. The roof box (2) has a base section (6) and a lid (4) for the storage of goods during transport. There are also provided means to accommodate a towing extension (24) and means to accommodate wheels (40) for conversion of the roof box (2) into a trailer. The towing extension (24) and the wheels (40) are removable to allow reconversion of the trailer to a roof box (2).

Description

A CONVERTIBLE ROOF BOX The present invention relates to a convertible roof box which may be adapted for use as a box trailer.

Box trailers have been in use for many years and generally comprise a support upon which the box is mounted, a towing extension or more complex towing framework which may comprise a simple shaft projecting from the front of the support frame and fitted with a suitable socket for attachment to a ball tow bar, and wheels located on either side of the box trailer and mounted on a common axle secured to the support frame.

Roof boxes are a more recent development for the storage of goods in transit and were designed as an improvement to the traditional method of securement of suitcases etc to a roof rack. A roof box is easily secured to a roof rack by means of suitable clips located on its base. Due to their location on the roof of the vehicle, roof boxes are designed for the transportation of"clean"leisure goods, whereas trailers tend to be used for the transportation of "dirty"heavy materials such as garden refuse, building materials, tools, engineering components etc.

It is one of the objects of the present invention to combine the functionality of the roof box and the box trailer.

According to the present invention there is provided a vehicle roof box comprising a lid and a base for storage of goods on the roof of the vehicle, wherein the roof box further comprises means to accommodate a towing extension and means to accommodate at least two spaced wheels for conversion of the roof box into a box trailer.

Preferably, the roof box includes a support frame, typically of the type fitted to the base of box trailers. Preferably, the support frame includes means to secure the towing extension thereto.

The support frame may also include means to mount at least two spaced wheels thereto. Preferably, such wheel mountings are located on respective support frame side members. Alternatively, the wheels may be secured directly to the roof box. Preferably, in such an arrangement the roof box is strengthened in the area of securement.

The support frame may be fixed to the interior or exterior of the roof box. Preferably, for safety reasons, the support frame is located on the exterior of the roof box.

It is also envisaged that other suitable means to secure the towing extension may be employed as alternatives to the support frame as will be appreciated by those skilled in the art. However, for practical and safety purposes, a support frame is preferred. As well as providing a possible mounting for the towing extension and wheels, the support frame is preferably designed to provide sufficient torsional rigidity to resist the forces applied during use as a trailer.

Preferably, each wheel is fitted separately to the roof box and, is, preferably, mounted on its own stub axle.

Preferably, in such an arrangement, the stub axle is journalled in a suitable suspension member which is secured to the roof box or the support frame side member.

According to a second aspect of the present invention there is provided a box trailer comprising a towing extension, a box secured to the said extension and wheels fitted to the box for locomotion, wherein the extension and wheels are designed to be storable for optional conversion of the trailer into a vehicle roof box.

Preferably, the trailer box is aerodynamically shaped in the manner of a roof box. Preferably, the towing extension and/or wheel assembly are removable and are removed prior to storage. Alternatively, the towing extension and/or wheel assembly may be folded into the body of the box during use as a roof box, thus obviating the need for removal.

Due to the greater likelihood of the box trailer becoming soiled, a suitable lining material may be provided for ease of conversion between soiled box trailer products and non-soiled roof box products.

Preferably, according to any aspect of the present invention, no tooling is required for conversion from the roof box to the trailer and vice versa.

According to a third aspect of the present invention, there is provided a method of converting a vehicle roof box in accordance with the first aspect of the present invention comprising the steps of:fitting a towing extension to the front of the roof box; and fitting wheels to respective sides of the roof box.

Preferably, the aerodynamic shape of the roof box includes forward tapering of the sides and, preferably, the lid and, preferably, the base of the roof box. Other means by which the roof box may be, preferably, aerodynamically shaped will be known to those skilled in the roof box art.

Preferably, the wheel assembly comprises a stub axle upon which the wheel is mounted, a socket in which the axle is journalled and a suspension unit from which the socket depends. Preferably, the suspension unit is substantially vertical and is secured at its upper end to the support frame side member or the roof box body. Preferably, the securement to the roof box or support frame side member is via an angular bush to prevent rotation of the suspension unit of the stub axle about a vertical axis. Preferably, the angular bush is in the form of a square. Preferably, the suspension unit includes a damping pad, a suspension pad, a shaft which extends from the socket and through the suspension pad, angular bush and damper pad, and a securing collar or nut to secure the upper end of the shaft to the roof box. Preferably, where the suspension unit is secured to the roof box itself, the angular bush is located in a hole or recess in the roof box base and, preferably, the roof box base is thickened by suitable moulding around the hole to provide sufficient resistance to the torsional forces acting on the bush.

Where the suspension unit is mounted onto the support frame it may also pass through the roof box or it may be mounted to the support frame alone. In the former case, the roof box may have any of the features as afore described. In either case, if the angular bush is located in a support frame mounting, the mounting may be suitably angular to accommodate the bush. Alternatively, the suspension unit may pass through the support frame mounting and into an angular bush located in the roof box body as before described. Typically, the support frame includes a wheel mounting means which is preferably, a plate extending from and secured to the side member and which includes a hole for accommodating the suspension unit shaft. It is envisaged that the mounting plate may extend inwardly under the roof base body or outwardly so that the suspension unit is spaced outwardly from the body. However, it is preferred that the mounting plate extends inwardly under the roof box body.

Preferably, the wheels are fixed to the roof box in such a manner that they may be removed by hand. Preferably, the interior of the roof box includes storage areas for the trailer wheels. Preferably, the towing extension is secured to the roof box in such a manner that it may be removed by hand. Preferably, the roof box interior includes a suitable area for safe storage of the towing extension. Preferably, the support frame remains secured to the box unit during both use as a roof box and roof as the trailer. Advantageously, use of the invention as a trailer increases the potential load which may be transported and, additionally, increases storage capacity by freeing the roof rack for use.

Preferably, the towing extension assembly includes a crank to raise the level of the towing socket to a suitable height for mating with the tow bar of a vehicle.

Embodiments of the invention will now be described with reference to the accompanying drawings in which:figure 1 shows a plan view of the trailer of the present invention; figure lb shows a side elevation of a trailer of the present invention ; figure lc shows a partial rear view of the trailer of the present invention; figure 2a shows a section through a suitable wheel assembly in accordance with the present invention; figure 2b shows a cross section through line A-A of figure 2a; figure 3a shows a plan view of a suitable support frame in accordance with the present invention; figure 3b shows a section along line X-X of figure 3a; figure 4 shows a possible mechanism by which the towing extension may be secured to the support frame.

Referring to figure 1, the roof box component 2 comprises a lid 4 and a base section 6. As can be seen from figure la, the sides of the roof box taper towards the front to improve the aerodynamics thereof. The sides 8,10 of the base section 6 are parallel with each other and, similarly, the front and rear of the front and rear 12,14 of the base section 6 are also parallel with each other.

The lid 4 of the roof box 2 is also shaped aerodynamically in the vertical plane as is most clearly seen from figure lb. This shaping comprises a vertical back plate 16 which extends forwardly into a convex arc 18 of relatively small radius which then further extends forward to a point vertically above the front of the wheels 40 in a concave arc of relatively large radius and then further extends to meet the front of the roof box in a further concave arc 22 of medium radius. The removable towing extension 24 comprises a crank 26 which is secured to and extends diagonally upwards from the front member 28 of the support frame 30, an elongate tubular section 32 which extends forwardly from the upper end of the crank 26 and a socket section 34 at the end of the towing extension and suitable for placing over the ball (not shown) of a tow bar. The wheels 40 are centrally disposed along the length of the roof box 2 and are mounted on stub axles 42 which are themselves journalled in a suitable socket 44 which is in turn mounted in the roof box as will be hereinafter described.

Referring to figure 2, an embodiment of the wheel assembly of the present invention is shown in which a wheel 50 is mounted on a stub axle 52 which is journalled at its other end in an axle socket 54 which in turn depends from a suspension shaft 56. The suspension shaft extends vertically upwards from the stub axle socket 54 through, in sequence, a suspension pad 58, a location bush 60, a damper 62 and a spring clipped collar 64. The location bush 60 is inserted in a suitably sized hole 66 formed in a thickened area of the base of the roof box 68. The moulding of the roof box floor 68 has been suitably thickened into a boss 69 of the same external diameter of the suspension pad 58 and substantially the same width thereas. The boss extends below the floor of the floor 68 of the roof box and increases the local strength of the roof box to resist the torsional forces of the bush located therein during use. The bush 60 has a square horizontal section on both its inner and outer walls to prevent turning of the wheel assembly in use and is accommodated in a centrally disposed hole 66 in the boss 69. The spring clipped collar 64 is of a conventional construction and may be released, by hand, by the user to allow the shaft 56 to be removed. The damper 62 which lies between the collar 64 and the top of the bush 60 is made from a suitable damping material. The damping material is a co-polymer of styrene and butadiene. A conventional mudguard 70 is mounted around the casing 72 of the stub axle 52. In use, the spring clip collar 64 may be removed from the top of the suspension shaft 56 so that the damper 62 and bush 60 located thereunder may also be removed and the wheel, axle and socket may then be removed by sliding the wheel vertically downwards with respect to the floor 68 of the roof box. A matching arrangement is provided for the wheel on the opposite side of the roof box. When conversion from a roof box into a trailer is required, the reverse of the above process may be carried out.

Referring to figure 3, a suitable support frame for the roof box is shown in greater detail. The support frame is of conventional construction having a front member 80, parallel opposite side members 82,84 and a rear member 86. In the arrangement shown, the parallel side members 82,84 and the rear member 86 are formed from a single'U' shaped tube which is welded at it two ends to the respective ends of the front member tube 80. A'T'shaped tubular collar 88 is located around the tubular front member 80 and centrally with respect to its ends. The base of the'T'shaped collar 88 provides a suitable mounting 90 for a cranked portion 92 of the towing extension (not shown). Wheel mounting plates 94,96 are located on opposite side members 82,84 of the support frame and each respectively extend inwardly therefrom.

Each mounting plate has a centrally disposed hole 98,100 formed therein for receipt of respective suspension shafts of wheel assemblies (not shown).

Referring to figure 3b, the respective circumferences of the front member and side members are shown in greater detail. The front member consists of a larger diameter tube to provide torque stiffness as a result of the forces acting on the front member via the towing extension (not shown). The side members are designed for flexural rigidity and comprise a smaller diameter tube compared to the front member.

Referring to figure 4, the mating of the various components of the towing extension are shown in greater detail. The connecting tee 110 has, mounted in the base 112 of the tee a crank member 114 which extends diagonally upwards and forwards from the connecting tee 110 before turning through a small angle to provide a horizontal neck portion 116 which is designed to receive a close fitting spigot 118 extending from the end of the main shaft of the towing extension (not shown). The spigot 118 is secured in the neck tube 116 of the crank member 114 by means of a pivot pin 120 which passes through co-operating holes in the neck tube 116 and spigot member 118 to secure the respective portions of the towing extension together. A suitably shaped recess is provided in the floor and front end of the roof box body (not shown) to partially accommodate the crank member 114 and the neck tube 116.

In use, the pivot pin may be removed by hand to allow the main shaft of the towing extension to be removed from the neck tube 116 for suitable storage. When conversion from a roof box into a trailer is required, the reverse process may be effected.

The components of the invention may be made from suitable materials. In particular, the roof box may be made from injection moulded polyethylene, polyvinyl chloride, polycarbonate or other suitable polymer material. The support frame may, for instance, be made from fabricated aluminium sections of circular hollow extrusion.

Similarly, the wheel assembly support brackets may, for instance, be made from cast aluminium alloy. The suspension blocks and damper blocks may, for instance, be made from styrene butadiene copolymer sheet or other suitable block copolymer. Where a box liner is used, low density polyethylene is a suitable material.

It will be appreciated that the shape of the roof box hereinbefore described is only one possible shape for the roof box and other suitable aerodynamic shapes for the roof box will be known to those skilled in the roof box art. The lid of the roof box is typically hinged but can also be removed for maximum flexibility. Typically, an area is designated within the box for storage of the towing extension and wheel assemblies in order to maintain the aerodynamic external shape while the invention is in the roof box mode. The device may be used in either a recreational or DIY mode and a simple polymeric liner may be provided to facilitate the switch between such modes.

To provide for local legal requirements, a number plate and lighting system may be fitted to the rear of the roof box and be designed to utilise the voltage electrical system of the relevant vehicle during the use in the trailer mode. Both the towing extension and the wheel assemblies may be designed to be assembled without the need for additional hand tools. After removing the towing extension from the relevant storage area within the box may be secured to the supporting frame by a solid shear pin an retaining clip. Similarly, after removal of the wheel assemblies from the storage space within the box they may be affixed to the box supporting structure or directly through the box itself via location holes and by utilising spring clips. The roof box may be secured to the roof of the vehicle by standard mechanical clamps or to a roof bar system by similar standard clamps.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment (s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

CLAIMS 1. A vehicle roof box comprising a lid and a base for storage of goods on the roof of the vehicle, wherein the roof box further comprises means to accommodate a towing extension and means to accommodate at least two spaced wheels for conversion of the roof box into a box trailer.
2. A vehicle roof box in accordance with claim 1, wherein the roof box is fitted with a support frame.
3. A vehicle roof box in accordance with any preceding claim, wherein the support frame includes means to secure the towing extension thereto.
4. A vehicle roof box in accordance with any preceding claim, wherein the support frame is located on the exterior of and around the base of the roof box.
5. A vehicle roof box in accordance with any preceding claim, wherein each wheel is fitted separately by means of a stub axle directly to the roof box or support frame of the roof box.
6. A vehicle roof box in accordance with any preceding claim, wherein the stub axle is journalled in a suitable suspension member which is secured to the roof box or a support frame side member.
7. A box trailer comprising a towing extension, a box secured to the said extension and wheels fitted to the box for locomotion, wherein the extension and wheels are designed to be storable for optional conversion of the trailer into a vehicle roof box.
8. A box trailer in accordance with claim 7, wherein the trailer box is aerodynamically shaped in the manner of a roof box.
9. A box trailer in accordance with claims 7 or 8, wherein the towing extension and/or wheel assembly are removable or retractable.
10. A method of converting a vehicle roof box in accordance with any of claims 1-6 comprising the steps of: fitting a towing extension to the front of the roof box; and fitting wheels to respective sides of the roof box.
11. A vehicle roof box in accordance with any preceding claim, wherein the aerodynamic shape of the roof box includes forward tapering of the sides.
12. A box trailer or a vehicle roof box in accordance with any of claims 1-9 or 11, wherein the wheel assembly comprises a stub axle upon which the wheel is mounted, a socket in which the axle is journalled and a suspension unit from which the socket depends.
13. A box trailer or a vehicle roof box in accordance with any of claims 1-9 or 11-12, wherein the suspension unit is substantially vertical and is secured at its upper end to the support frame side member or the roof box body.
14. A box trailer or a vehicle roof box in accordance with any of claims 1-9 or 11-13, wherein the securement to the box or support frame side member is via an angular bush and complimentary bush receiving hole to prevent rotation of the suspension unit of the stub axle during locomotion.
15. A box trailer or vehicle roof box in accordance with any of claims 1-9 or 11-14, wherein the suspension unit includes a damping pad, a suspension pad, a shaft which extends from the socket through the suspension pad, angular bush and damping pad, and a securing device to secure the upper end of the shaft to the roof box.
16. A box trailer or vehicle roof box in accordance with any of claims 1-9 or 11-15, wherein the box is strengthened by a suitable moulding around the bush receiving hole to accommodate the angular bush.
17. A box trailer or vehicle roof box in accordance with any of claims 1-9 or 11-16, wherein the interior of the box includes storage areas for the trailer wheels.
18. A box trailer or vehicle roof box in accordance with any of claims 1-9 or 11-17, wherein the box interior includes a suitable area for safe storage of the towing extension.
19. A box trailer or vehicle roof box in accordance with any of claims 1-9 or 11-18, wherein the towing extension assembly includes a crank to raise the level of the towing extension to a suitable height for mating with the tow bar of a vehicle.
20. A vehicle roof box as hereinbefore described with reference to the accompanying drawings.
21. A box trailer as hereinbefore described with reference to the accompanying drawings.
22. A method of converting a box trailer in accordance with any of claims 7-9,12-19 or 21 comprising the steps of: (a) storing the towing extension; and (b) storing the wheels.
23. A method of converting a box trailer into a vehicle roof box as hereinbefore described with reference to the accompanying drawings.

23. A method according to claim 22, which includes the step of: removing the towing extension prior to storage step (a).

24. A method according to claim 22, which includes the step of: removing the wheels prior to storage step (b).

22. A method of converting a vehicle roof box into a box trailer as hereinbefore described with reference to the accompanying drawings.