TITLE: METHOD OF MANUFACTURING TRAILERS

BACKGROUND OF THE INVENTION 1. Field of the Invention

THIS INVENTION relates to a method for manufacturing trailers.

The invention also relates to a metal panel which is suitable for the manufacture of the floors of the trailers; and for the sides and tops of bodies for the trailers.

The method of the invention may also be applied to manufacturing load-carrying trays and/or bodies for other vehicles such as cab/chassis vehicles.

The invention also relates to a method of manufacture which enables optional accessories to be subsequently fitted thereto, such as for rental or hire purposes. 2. Prior Art

The manufacture and sale of relatively light-weight trailers, eg., of the type towed behind automobiles, utilities, light trucks, is generally locally or regionally based. (Typically, light-weight trailers have single-/dua!-tri- axles and a load carrying capacity not exceeding 2-3 tonnes.) Any person with a modicum of mechanical skills and a small amount of equipment (eg., a power hacksaw, an electric welder and an oxy- acetylene set) can set themselves as a manufacturer of trailers. Because such persons can operate on relatively small profit margins, it is difficult for larger manufacturers to compete on price.

Another difficulty for larger manufacturers is that non-standard trailers must be built on a custom basis.

As trailer distributors and retailers cannot hold a large range of stock in anticipation of each possible trailer/accessory combination sought by a client (eg., a 6' x 4' single axle trailer with cages/large tool box/side steps), a customer usually has to wait until his/her specific trailer can be manufactured and supplied to the distributor/retailer.

SUMMARY OF THE PRESENT INVENTION

It is an object of the present invention to provide a method for the manufacture of floors for trailers (or the load-carrying trays of other vehicles).

It is a preferred object to provide a method which can be extended to the manufacture of the sides and/or tops (or roofs) of the trailers (or load-carrying trays). It is a further preferred object to provide a metal panel which enables the floors/sides/tops to be manufactured on a modular basis.

It is a still further preferred object to provide a manufacturing method where additional metal sections can be added to the panels to increase the strength of the floors and/or allow easy installation of a range of accessories.

It is a still further preferred object to provide a method where the accessories can be subsequently fitted for purchase, rental or hire.

Other preferred objects will become apparent from the following description.

In one aspect, the present invention resides in a metal panel suitable for the manufacture of trailers or other vehicles, including: a first planar portion, substantially rectangular in plan view, and bounded alone one side by a substantially perpendicular flange; a substantially U-shaped portion along a second side of the first planar portion and extending in the same direction as the perpendicular flange; a second planar portion connected along a first side to the U- shaped portion and lying parallel to, but offset from, the first planar portion; and a substantially L-shaped flange connected to a second side of the second planar portion and extending in the same direction as the U- shaped portion.

Preferably, the metal panel is folded or rolled from sheet metal (eg., steel or aluminium); and the offset of the second planar portion to the first planar portion is substantially equal to the thickness of the sheet metal.

Preferably, the spacing between the side walls of the U-shaped portion is substantially equal to the thickness of the sheet metal; the perpendicular flange of one metal panel is adapted to be engaged in the U- shaped portion of a second metal panel; and the region of the first planar portion of the one metal panel, adjacent to the perpendicular flange, overlies the second planar portion of the second metal panel.

Preferably, a distal edge of the foot portion of the L-shaped flange is spaced from the U-shaped portion by a distance which is just

smaller than the distance of the distal edge to the leg portion of the L-shaped flange (ie., the width of the foot portion).

In a second aspect, the present invention resides in a method for manufacturing a floor, side(s) and/or roof of a trailer (or load-carrying vehicle) including: placing a plurality of the metal panels, as hereinbefore described, in side-by-side relationship, where a first planar portion of one metal panel overlies a second planar portion of an adjacent metal panel, and the perpendicular flange of the one metal panel is engaged in the U-shaped portion of the second metal panel.

The respective portions of the adjacent metal panels can be secured together, eg., by welding, riveting, clinching and/or by fasteners (eg., screws, studs) (preferably) through the overlapping first and second planar portions and/or through the U-shaped portions and perpendicular flanges. The U-shaped portion, second planar portion and L-shaped flange of a metal panel forms a substantially rectangular, more preferably square, elongate cavity in end view, the cavity being partially open along one side; and a substantially C-shaped metal section may be located within the cavity, where a slot between a pair of inwardly-directed, substantially planar, flanges in the C-section, at least partially aligned with the partially open one side of the cavity.

An anchor block or plate, having at least one screw threaded bore, may be received in the cavity and be engaged by one or more bolts to

releasably secure brackets for the attachment of accessories such as jerry can holders, tool boxes, water tanks, ramps or the like to the chassis.

In a third aspect, the present invention resides in a method of operating a trailer including the steps of: a) purchasing a trailer (or load-carrying vehicle) having at least a floor manufacturing by the method of the second aspect; and b) subsequently purchasing, renting or hiring at least one accessory to be detachably fitted to the trailer to enable the trailer to be used for an alternative load carrying purpose. Such alternative purposes may include: a) for the transport of tanks (eg., for water storage) or machinery; b) for the transport of small vehicles, such as lawn mowers, quad-bikes, trikes, golf buggies or motorcycles; c) as automobile-carrying trailers; d) as box trailers, with or without covers, cages; e) as enclosed trailers, such as pantec trailers, tradesmen trailers, enclosed vans and luggage trailers; f) as camping trailers; g) as caravans; h) as storage, building or office trailers; and i) as horse- or stock-floats.

(This list is not exhaustive, but is by way of illustration only.)

BRIEF DESCRIPTION OF THE DRAWINGS

To enable the invention to be fully understood, preferred embodiments will now be described with reference to the accompanying drawings, in which: FIG. 1 is a top isometric view of a first embodiment, showing a trailer having a box-floor manufactured in accordance with the present invention;

FIG. 2 is an underside view of the trailer corresponding to FIG.

1; FIG. 3 is an isometric top view of two of the metal panels employed to manufacture the trailer of the first embodiment;

FIG. 4 is an end elevational view of a metal panel;

FIG. 5 is an end elevational view of one end of the panel (at Detail A on FIG. 4) drawn on a larger scale; FIG. 6 is an isometric view showing a number of the metal panels joined together;

FIG. 7 is a similar view to FIG. 6, but on a larger scale;

FIG. 8 is an underside view corresponding to FIG. 7;

FIGS. 9A to 9H shows the steps of fitting a C-section into the cavity at one end of one of the metal panels;

FIG. 10 shows an isometric view of the mounting of an accessory bracket to the floor of the trailer;

FIG. 11 is a corresponding end elevational view;

FIG. 12 is an isometric view showing a second embodiment of

a trailer, having side walls also manufactured from the metal panels;

FIG. 13 is an isometric rear view of a "PANTECH"-style body for the trailer of FIG. 12, where the roof is also manufactured from the metal panels; FIG. 14 is a top isometric view of a third embodiment, showing lawnmower trailer manufactured using the metal panels;

FIG. 15 is a bottom isometric view thereof corresponding to FIG. 14;

FIG. 16 is a "partially-exploded" top isometric view of a fourth embodiment, showing car-carrying trailer with a floor manufactured using the metal panels; and

FIG. 17 is an "exploded" bottom isometric view corresponding to FIG. 16;

FIGS. 18 to 34 are isometric views illustrating alternative embodiments of trailers which can be manufactured from the metal panels;

FIG. 35 is a view similar to FIG. 34 on a larger scale;

FIGS. 36 and 37 show the setting of a horse- or stock-float body to a "universal trailer"; and

FIGS. 39 to 41 are respective isometric views of the horse- or stock-float body.

DETAILED DESCRIPTION OF THE

PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2, the trailer 10, of a first embodiment which is a single-axle (eg., 1.8m x 1.2m/6' x 4') box trailer with a hinged tail

gate, has a load box 11 with a front wall 12, side walls 13, 14 and a hinged tail gate 15 all formed of rolled metal section and connected at the corners by C-section posts 16.

As shown in more detail in FIG. 2, the trailer 10 has a peripheral frame 16a formed of C-section steel to which the draw bar 17 and the springs 18 for the axle 19 are attached (by suitable hangers). (It will be readily apparent to the skilled addressee that the leaf springs 18 can be replaced by other suitable suspension units, including trailing or leading arms with coil springs or airbags, rubber suspension or the like.) The floor 20 is assembled from a plurality of metal panels 30, to be hereinafter described in more detail with reference to FIGS. 3 to 8, where the panels 30 are interconnected together along opposed sides.

Referring more particularly to FIGS.4 and 5, each metal panel 30 has a first planar portion 31 , substantially rectangular in plan view, which is bounded along one side by a substantially perpendicular flange 32.

The other side of the first planar portion 31 is bounded by a substantially U-shaped portion 33 which extends in the same direction as the perpendicular flange 32 and is connected to a first side of a second planar portion 34, also substantially rectangular in plan view, which lies parallel to, but offset from the plane of the first planar portion 31 by an amount substantially equal to the thickness (T) from which the metal panel 30 is formed.

A substantially L-shaped flange 35 is connected to a second side of the second planar portion 34 and extends in the same direction as

the U-shaped portion 33.

A distal edge 36 of the foot portion 37 is spaced from the U- shaped portion 33 by a distance (d) smaller than the distance (D) of the distal edge 36 to the leg portion 38 of the L-shaped flange 35. The U-shaped portion 33, second planar portion 34 and L- shaped flange 35 form a substantially square elongate cavity 39 in the metal panel 30, the cavity 39 being partially open along one side at opening 42.

The distance (X) between the adjacent walls 40, 41 of the U- shaped section 33 is equal to, or just greater than, the thickness (T) of the metal from which the metal panel 30 is formed.

Preferably, the metal panel 30 is folded to shape, eg., in a press brake; although a portion of the metal panel 30 may be roll-formed to shape, eg., to produce the perpendicular flange 32.

To assemble the floor 20, adjacent panels 30 are overlapped where a section of the first planar portion 31 is located above the second planar portion 34 of a second like panel 30 and the perpendicular flange 32 of the first panel 30 is aligned with the U-shaped portion 33 of the second panel 30. On bringing the two panels 30 together, the perpendicular flange

32 of the first panel 30 is received in the U-shaped portion 33 of the second panel 30 and the first planar portion 31 is substantially co-planar with the adjacent first planar portion 31 of the second panel 30.

The panels 30 may be secured together by "TEK-SCREWS" (trade mark) or other fasteners (F), either driven through the overlaid first and second planar portions 31 , 34, or more preferably through the engaged

perpendicular flanges 32 and U-shaped portions 33.

The required number of panels 30 are inter-engaged until the floor 20 of the required dimension has been produced. For example, the floor 20 in FIGS. 6 and 7 incorporates five (5) of the metal panels 30 interconnected together.

The floor 20 may be fixed to the peripheral flange 16 by welding or secured thereto by suitable brackets and fasteners (not shown).

In certain applications, reinforcing of the floor 20 may be required; or accessories such as ramps (eg., as will be described with reference to FIG. 17) may be secured to the underside of the floor 20.

As shown in FIGS. 9A to 9H, a C-shaped metal section 50 may be located in the cavity 39 by way of the progressive installation steps illustrated in FIGS. 9A to 9H. In the final position illustrated in FIG. 9H, a side wall 51 of the C-section 50 is located against one side wall 40 of the U- shaped portion 33, and the slot 52 in the metal section 50 is aligned with the opening 42 in the cavity 39, the effective width of the opening 42 being reduced by the flange 53 of the C-section 50.

The metal section 50 may be securely located in the cavity 39 by fasteners (F) through the side wall 51 of the C-section 50 and side wall 40 of the U-shaped portion 53.

The slot 52 in the C-section 50 enables the mounting of accessories in the manner to described in more detail with reference to FIGS. 10 and 11.

Referring to FIGS. 10 and 11, a mounting assembly 60 for a

trailer accessory, eg., the car ramps to be hereinafter described, has a plate 61 with a screw-threaded bore (not shown) which receives the shank 62 of a bolt 63, the head 64 of which engages the foot 65 of an L-shaped mounting bracket 66. It will be noted that the mounting block 61 clamps the flange 54 of the C-section 50 to the foot 37 of the L-shaped flange 35 to prevent movement of the C-section 50 within the cavity 39.

While the plate 61 shown only has a single bore to receive a single bolt 63, the plate 61 may be elongated and have two (2), three (3), or more, bores engageable by respective bolts 63, the plate 61 enabling the fixing of extended brackets, or a plurality of brackets 66.

FIG. 12 illustrates how the front end wall 112 and side walls

113, 114 of a box-trailer 110 of a second embodiment can be manufactured using the metal panels 30 hereinbefore described. As illustrated in FIG. 13, C-section corner posts 116 interconnect the walls 112, 113, 114 at the corners of the trailer body, and provide a peripheral frame for the rear end of a "PANTECH" body 115 on the trailer 110, where the roof 117 is also manufactured from the interlocking metal panels 30 in the same manner as the manufacture of the floor 120, the roof 117 having a peripheral frame 118 formed of the C-section members of the same profile as the corner post 116.

A tail gate, not shown, may be hingedly mounted on the rear head rail 118A of the peripheral frame 118 to enable the "PANTECH" body 115 to be fully closed.

It will be readily apparent to the skilled addressee that the walls

112, 113, 114 can be erected to any suitable modular height based on the width of the panels 30.

FIGS. 14 and 15 show the manufacture of a "lightweight" (eg., below 500kg load-capacity) mower trailer 210, where the floor 220 is manufactured from the metal panels 30 in the manner hereinbefore described. The front wall 212 and side walls 213, 214 are connected to a peripheral frame 216 with corner posts 216A which hingedly support the tail gate 215. The axle 219 is welded to, or otherwise mounted on, C-section mounting blocks 260 welded or otherwise secured to the floor 220. (Rubber suspension blocks may be provided between the axle 219 and the C-section mounting blocks 260, or the axle 219 and the floor 220.)

The axle 219 has a pair of wheels 261 located via respective spacers 262; and the drawbar 217, of C-section steel, is secured by suitable mounting assemblies (eg., of the type shown in FIGS. 10 and 11) secured to the floor 220.

A double-axle car trailer 310, of a fourth embodiment, illustrated in FIGS. 16 and 17, has a floor 320 manufactured from the metal panels 30 as hereinbefore described and is provided with C-section side rails and a draw bar 317. As shown in FIG. 17, a ramp assembly 390 has a pair of ramps

391 releasably secured in a substantially U-shaped ramp carrier 392, where the side rails 393 of the ramp carrier 392 are secured to the underside of the floor 320 using the mounting assemblies 60 illustrated in FIGS. 10 and 11.

In this embodiment, it is preferable that strength of the floor 320

is reinforced in strength by the inclusion of the C-sections 50 in some, or all, of the cavities 239 in the panels 30 from which the floor 320 is constructed.

By the use of the metal panels 30, it is possible for a trailer manufacturer to easily produce a series of "universal" trailers, with either single-or double-axles, or sizes such as 1.8m x 1.2m (6' x 4')/2.4m x 1.5m (8' x 5')/3.0m x 1.8m (10' x 6'). The production of such "universal" trailers recognises the following matters: a) a person who purchases, eg., a box-trailer will no double, at some time have the need for a different type of trailer, eg., to move furniture or a vehicle, even if only on a once-off basis; and b) the manufacturer or hire business could rent an alternative body to the customer, to fit to his/her own trailer, so that the customer does not have to rent an unfamiliar trailer, with the difficulties that may bring (eg., ensuring correct electrical and/or braking connections between the tow-vehicle and the rented trailer).

By manufacturing/offering for sale such "universal trailers", a customer can purchase such a trailer and register his/her details with a rental organisation. Such details could include: a) full name; b) address; c) contact details (telephone/e-mail); d) trailer VIN/chassis number; e) credit card details.

When the need arises, the consumer can visit the rental outlet

and hire the body and/or accessories required for a particular task, eg., to transport motorcycles, furniture, work tools or the like. As the rental outlet has the consumer's details stored, rental paper work can be minimised/ eliminated and, eg., discounts automatically granted to high-frequency users. Alternatively, a consumer could purchase a "universal" trailer, together with a tradesman's body to transport his/her work tools during the week and motorcycle fittings to transport motorcycle(s) on the weekends/vacation^). The consumer only has one trailer to register/insure/ maintain/house. In this way, the consumer obtains maximum return for his/her financial outlay.

FIGS. 18 to 30 illustrate a range of trailers possible with a single-axle "universal" trailer; while FIGS. 31 to 34 illustrate a range of trailers possible with a direct-axle "universal" trailer (in addition to the car-carrying trailer 30 of FIGS. 16 and 17).

FIGS. 18 to 30 illustrate as follows: a) FIG. 18: "universal" trailer 410 and trailer for transporting (water storage) tanks and/or machinery; b) FIG. 19: trailer 410A for transporting lawn mowers/small garden trailers/quad bikes/golf buggies (with two wheel ramps); c) FIG. 20: trailer410Bfortransporting motorcycle(s) (with one wheel ramp); d) FIG. 21 : box-trailer 41 OC (with hinged tailgate(s)); e) FIG. 22: box-trailer 410D with hinged cover;

f) FIG. 23: "pantec"-type trailer 41 OE; g) FIG. 24: tradesman's trailer 410F (for the covered transport of tools and work supplies); h) FIG. 25: box-trailer with cage 41 OG; i) FIG. 26: "flat-bed" trailer with cage 410H; j) FIG. 27: box-trailer (with sides formed of the metal panels 30) and cage; k) FIG. 28: enclosed van or luggage trailer 410J;

I) FIG. 29: flat-deck trailer 41 OK (where the deck overlies the wheels); and m) FIG. 30: foldable camping trailer 41 OL (with annexe).

Similarly, a dual-axle "universal" trailer 510 can provide the basis for the following range of trailers: n) FIG. 31 : trailer for transporting a lockable storage unit/container 51 OA; o) FIG. 32: trailer for transporting a caravan body 51 OB; p) FIG. 33: trailer for transporting a portable building or office 510C; q) FIG. 34: trailer for transporting a horse- or stock-float body 51 OD (to be described in more detail with reference to FIGS. 35 to 40).

Referring now to FIGS. 35 to 40, a dual-axle "universal" trailer 510 is manufactured from the metal panels in the manner hereinbefore described.

A two-animal horse- or stock-float body 51 OD is manufactured

for detachable mounting on the "universal" trailer 510.

The float body 510D may be secured by releasable latches or via trust-locks of the type used for shipping containers.

The float body 51 OD has a corrugated floor 590, side walls 591 and 592, a curved (lowered-wind-resistance) float wall 593 and roof 594. An internal divider wall 595 extends along the centre-line of the float body 510D, which is provided with access doors 596, 597 and windows 598.

The components of the float body 51 OD may be manufactured from steel/aluminium/plastics/fibreglass or other suitable materials. As required, a consumer can visit a rental operation with his/her

"universal" trailer 510 and select the body 510A-510D appropriate for his/her needs.

In addition, if required, the bodies 510A-510C can be transported to, and left, on-site at a desired location until no longer required, whilst providing secure storage for the contents therein.

By purchasing a single "universal" trailer 410, 510, a consumer has access to a wide range of potential load-carrying alternatives.

In addition, for the manufacturer, they can sell a "universal" trailer at a premium (eg., for AU $900-1000) against a competing trailer (eg., @ AU $750-800) because the "universal" trailer" has the ability to be used in the future with the wide range of alternative bodies described and illustrated.

It will be readily apparent to the skilled addressee that the use of the metal panels 30, which can be relatively inexpensively manufactured, enables the flexible, modular, manufacture of a wide range of trailers, so that

modular production techniques enable considerable cost savings to be enjoyed.

By selective shape (and size) of the panels 30, the panels 30 can be used to manufacture not only the floors of the trailers, but also the sides and the roofs for, eg., "PANTECH" type trailers.

The manufacturing method, using the metal panels 30 hereinbefore described and illustrated, enables the trailers to be produced with a wide range of dimensions, from a small single-axle box trailer or lawnmower trailer to a large (eg., tri-axle) car carrier or fully enclosed "PANTECH" type trailer. The dimensions/gauge of the metal panels 30 can be varied to suit different size/load-rated trailers; and the C-sections 50 can both add strength and allow easy installation of a wide range of accessories.

It will be readily apparent to the skilled addressee that the method of manufacturing the trailer floors/sides/bodies can also be applied to other vehicles such as the manufacture of load trays and bodies for light trucks and other cab/chassis vehicles.

Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention.