WO2006005101A1

WO2006005101A1 - Softride towbar

Info

Publication number: WO2006005101A1
Application number: PCT/AU2005/000933
Authority: WO
Inventors: Laurie Caruana
Original assignee: Laurie Caruana
Priority date: 2004-07-09
Filing date: 2005-06-27
Publication date: 2006-01-19

Abstract

A soft-riding towbar assembly (not numbered) suitable for fitting to vehicles. The soft-riding towbar assembly smooths out the shocks, jarring and vibrations experienced by trailed vehicles and caravans when travelling, especially over rough or corrugated roads or terrain. In a preferred embodiment, the soft-riding towbar assembly uses a pivoting torque axle suspension system, consisting of rubber elements (8) in contact with a square, S-cam or triple fluted section torsion bar (7) and held on the outside by corresponding square or hexagonal sided hollow section torsion housing (3). Suspension movement between bump and rebound compresses the rubber elements (8) thus providing a dampening of road shocks.

Description

SOFTRIDE TOWBAR

The drawings relating to the invention will now be described, in which:

Fig.l is an isometric view of one embodiment of the invention, showing the main frame 1, supported by and welded to the two chassis mounting plates 2, and supporting the two torsion housings 3, one on either side of the receiver tube 4, which in turn houses the tow-ball tongue 5, which accommodates the tow-ball (not shown) to which the trailer or caravan is attached for towing. Also shown is a safety chain lug 6, of which there is one on each side of the tow- ball tongue 4, for safety in the event of failure or disconnection of the trailer or caravan.

Fig.2 is a close-up of some of the centre working components of the embodiment of Fig 1, ■ showing in some detail the receiver tube 4, and the tow-ball tongue 5 in place, with the pin and "R" clip also in place. The torsion housings 3 are secured in position by a plurality of bolts 14, with spacers 13 as required for the particular fitting.

Fig.3 is a plan view of the assembly of Fig 1, and shows.the main frame 1, the torsion housings 3, welded to the receiver tube 4, the plurality of bolts fastening the torsion housings 3 to the main frame 1, the tow-ball tongue 5 in position, and the two safety chain lugs 6, one on each side of the tow-ball tongue 5.

Fig 4 is a rear elevation view of the embodiment of Fig 1, showing the main frame 1, the torsion housings 3, the receiver tube 4, and the safety chain lugs 6.

Fig 5 is an exposed side view of the torsion bars 7 and torsion rubber elements 8 of the embodiment of Fig 1 , with a close-up view of the four torsion rubber elements 8, held in place inside the hollow square-section torsion housings 3, and the square-section torsion bars 7 also in place.

Figs 6a and 6b show an alternative embodiment of the invention, where the torsion bars 7 are made up of S-cam section, with the four torsion rubber elements positioned and held as shown inside the square hollow section torsion housings 3. Figs 7a and 7b show another alternative embodiment of the invention, showing the torsion bars made up of triple fluted section, with three torsion rubber elements held in place inside the hexagonal hollow section torsion housings 3 in the assembly.

Fig 8 is an isometric view of the embodiment of Fig 7, showing the triple-fluted torsion housings 3 in place in the assembly.

Fig 9 is another alternative embodiment of the invention, and shows a coiled spring in place of the torsion housings and bearing blocks 10 carrying the torsion bars 7, which are round in this embodiment, allowing them to turn within the bearing blocks as the tow-bar oscillates.

Figs 1Oa and 10b show another alternative embodiment of the invention, and shows a shock absorber 12 in place and anchored in place by the shock absorber anchor frame extension 11.

Fig 11 is yet another alternative embodiment of the invention, in which the torsion bars 7 are round, and are of spring steel, torsion bar material, as is well-known in the art. These torsion bars 7 are fixed at the outer ends into splined housing blocks 10, so that they are able to twist as the load comes on to them, and twist back as the load is reduced.

Figs 12a and 12b show yet another alternative embodiment of the invention, with both the load spring 9 and the shock absorber 12 on the same side of the tow-bar pivot point, and with the shock absorber 12 fitted inside the spring 9.

The invention and its operation will now be described with reference to the above drawings:

Referring to Fig 1, the vertical chassis mounting plates 2 are securely bolted to the chassis of the towing vehicle, such towing vehicle being a truck, bus, 4WD or other vehicle, which is capable of towing a trailer or caravan at speed over all kinds of terrain. Welded or clamped to these chassis mounting plates 2 is the transverse main frame 1, which carries the torsion housings 3, which in turn houses the two torsion bars 7, which are welded to the receiver tube 4, one on each side.

Fitted into the spaces between each torsion bar 7 and each torsion housing 3 are the torsion rubber elements 8, which take the load in a flexible manner. These torsion rubber elements are made of suitable compressible material such as natural or synthetic rubber, polyurethane, or other suitable and compressible material such as is well-known in the art.

When the assembly is securely bolted to the rear of a chassis of a truck, bus or other firm vehicle, a tow-ball is fitted in the normal manner to the tow-ball tongue 5, and a trailer or caravan is then connected with a matching tow-ball socket to the assembly, the tow-bar 5 in the receiver tube 4 swings down under the weight of the trailer or caravan, thereby partially compressing the torsion rubber elements 8. As the towing vehicle moves off, gathers speed, and goes over undulating, rough or corrugated terrain or roads, the flexibility and compressibility of the torsion rubber elements 8 allow the torsion bars 7 to oscillate up and down, thereby taking up the whiplash and jarring effect which is otherwise present in the connection. This has the effect of a much- smoother and softer ride for the trailer or caravan, resulting in a much longer life for the drawbar, frame, chassis, body and other components in the trailer or caravan.

In the case of the Fig.9 embodiment of the invention, the movement is taken xφ by the coil spring 9 in the place of the rubber elements 8 described above. Similarly, the sudden vertical movements and oscillations of the towing vehicle are taken up and absorbed by the coil spring 9, thereby smoothing out the vertical travel of the trailer or caravan.

In the embodiment shown in Fig 1Oa and 1Ob, the load and movement is taken up by the shock absorber 12, which may be assembled in association with the embodiment shown in Fig 9, having a spring to the rear of the pivot point 16, and a shock absorber 12 in fient of the pivot point 16. In the embodiment shown in Fig 11, the movement and load is taken up by special spring- steel torsion bar elements 7, which are anchored at their respective outer ends in by way of a spline or other suitable method in the outer bearing blocks 10, being able to turn and twist in the inner bearing blocks, thus allowing for movement and smoothing out of the ride.

In the embodiment shown in Figs 12a and 12b, the shock absorber 12 is shown fitted inside the coil spring 9, which is in contact with, and anchored to an extension 15 of the receiver tube 4 to the other side of the pivot point 16 from the tow-ball tongue 5, As will be readily apparent, when the tow-ball 5 moves in a downward direction, the spring 9 is compressed, and vice-versa. The shock absorber 12 dampens the movements of the tow-ball and tow-ball tongue 5. This allows for a much neater and tidier assembly, and still allows for the vertical movement of the tow-ball tongue and receiver tube assembly as previously described, thus smoothing out the ride and minimising the stresses for the trailed vehicle.

Fig. 13 shows another embodiment of the invention, where the transverse main frame 1 is clamped, rather than welded in situ, to the vertical chassis mounting plates 2, by way of the clamping devices 17 which are welded to the vertical chassis mounting plates 2. This embodiment enables the entire invention to be constructed in the workshop, and shipped in a kit form, to be assembled and easily fitted to a towing vehicle in any remote or third world location, with a minimum of tools and spanners.

As will be seen upon an examination of the associated drawings and the description, this invention allows for very comprehensive combinations of components and movements which allow the device to carry out the same smoothing out effect as outlined in the description above. It is the intention of the inventor to disclose an exemplary number of these combinations of components. Various other combinations of components may be used, without departing from the concept of this invention. LAURIE CARUANA PATENT

LEGEND

1. MAINFRAME

2. CHASSIS MOUNTING PLATES

3. TORSION HOUSINGS

4. RECEIVER TUBE

5. TOWBALL TONGUE, WITH PIN AND ^ςR' CLIP

6. SAFETY CHAIN LUGS

7. TORSION BARS (SQUARE, S-CAM AND TRIPLE FLUTED)

8. TORSION RUBBERS

9. SPRING

10. BEARINGBLOCKS

11. SHOCKABSORBERANCHORFRAME

EXTENSION

12. SHOCKABSORBER

13. SPACER

14. BOLTS

15. RECEIVERTUBEEXTENSION

16. PIVOTPOINT

Claims

CLAIMS.What I claim is:

1. A soft-riding tow-bar device including a tow-bar assembly, which includes means to take the vibration and whiplash out of the towbar connection between a towing vehicle and a trailer or caravan, thereby saving such trailer or caravan from the damaging affect of such whiplash, jarring and vibration, with the associated saving of the towbar, chassis, and frame of the trailed vehicle, the said assembly comprising a main frame, chassis mounting plates, torsion bar housings, a tow-bar receiver tube, a tow-bar tongue, at least two torsion bars, torsion rubber elements, bearing blocks, and safety chain lugs.

2. A tow-bar device as in Claim 1 , in which the means of smoothing out the vertical movement, thus softening the ride of a trailed vehicle, by introducing and allowing vertical movement into the tow-bar of the towing vehicle in such a manner as to take up the jarring and shock of sudden bumps and holes in the road or terrain, by way of the use of flexible parts and components so designed and fitted that such shock, jarring and vibrations in the trailed vehicle are significantly reduced, and smoothed out.

3. A tow-bar device as in Claims 1 and 2, whereby the vertical movement of the tow¬ bar tongue is regulated and controlled by a plurality of rubber elements, which are held in place, and in between the said torsion bars, and the outer torsion housings, in such a manner as to provide a cushioning effect of the sudden jarring vertical movement of the drawbar of the towing vehicle.

4. A tow-bar device as in Claims 1 thru 3, in which the means of smoothing out the jarring and sudden vertical movements of the towing vehicle is achieved by way of torsion bars made of special spring steel, with the outer ends of such torsion bars anchored, and allowing the said torsion bars to twist within their respective inner carrier bearings.

5. A tow-bar device as in Claims 1 thru 4, in which the means of achieving the said smoothing out and softening the ride of the trailed vehicle is achieved by way of a steel coiled spring, such spring having a shock absorber fitted inside the spring, to take up the shock, jarring, vibrations and whiplash which would otherwise be present hi such a connection.

6. A tow-bar device as described in the above claims 1 thru 5, substantially as described with reference to the accompanying drawings.

DATED this <£- ^tL day of June, 2005