AU2021105791A4 - Steerable dog trailer caravan - Google Patents

Abstract

A caravan with a dog trailer chassis that has Active Spare Wheels mounted in the centre region of the chassis that can be raised or lowered by remote control. When the Active Spare Wheels are in the raised position, the caravan behaves as a dog trailer and is suitable for driving forward on the road at speed. When the Active Spare Wheels are in the lowered position, the caravan is lifted upwards, rests on these 2 wheels and is suitable for reversing and parking. 000 O'. 00

Description

O'. EDITORIAL NOTE

2021105791

THERE ARE FOUR PAGES OF DESCRIPTION ONLY

Title of Invention - STEERABLE DOG TRAILER CARAVAN

Field of Invention - This invention relates to caravans. To be more specific, this invention pertains to steerable dog trailer construction.

Background of the Invention

[0001] Recreational caravans are designed and built using either single or double axles mounted in the centre region of the chassis. This allows for good manoeuvrability of the caravan when turning in both forward and reverse directions.

[0002] However, this design results in a number of dangerous problems when driving at speed on the road. These include caravan sway from strong winds and passing truck turbulence and sway from caravan uneven weight distribution due to poor loading of the caravan. Caravan sway can lead to caravan jack knife and vehicle rollover.

[0003] The dog trailer design, which has wheels located near the 4 corners of the chassis, is inherently more stable and therefore more stable when driving forward on the road at speed. Dog trailers are typically used in industry to cart heavy loads but are not used for recreational caravans because they are difficult to manoeuvre and particularly when turning or reversing to park.

Prior Art

[0004] Australian patent application AU2014200692A1 discloses a central pivot mechanism to improve the control of reversing a dog trailer.

Summary of Invention

[0005] This invention provides an easy and quick method of alternating between 4 wheel dog trailer and 2 wheel conventional caravan operations and provides safe driving when driving on the road at speed with superior manoeuvrability when turning and reversing compared to Prior Art.

[0006] This invention provides a caravan with a dog trailer chassis that has Active Spare Wheels mounted in the centre region of the chassis that can be raised or lowered by remote control. When the Active Spare Wheels are in the raised position, the caravan behaves as a dog trailer and is suitable for driving forward on the road at speed. When the Active Spare Wheels are in the lowered position, the caravan is lifted upwards, rests on these 2 wheels and is suitable for reversing and parking.

[0007] The rams that operate the Active Spare Wheels can be either hydraulically or electrically driven.

Details of Invention

Details of how the invention works are with reference to Figures 1, 2, 3 & 4.

DRAWINGS LEGEND 1. Tow Vehicle 12. Lock Bar Pivot 2. Tow Ball Hitch 13. Lock Bar to A-Frame Draw Bar Bolt 3. Trailer/ Caravan Chassis 14. Captive Nut 4. Active Spare Wheel 15. Front Draw Bar 5. Bell Crank 16. Front Draw Bar Pivot Levelling Handle 6. Bell Crank Pivot 17. Front Draw Bar Pivot 7. Electric / Hydraulic Cylinder Ram 18. Front Turn-Table Steering Axis 8. Dog Trailer Wheel 19. Caravan Body 9. A-Frame Steerable Draw Bar 20. Caravan Body to Lock Bar Retainer Nut 10. A-Frame Steerable Draw Bar Pivot 21. Elongated Hole 11. Lock Bar

[0008] Tow Vehicle (1) and Trailer/ Caravan Chassis (3) and body (19) pull up in a straight line. See fig 1

[0009] Driver removes Lock Bar Bolt (13) from Retainer Nut (20) then lowers Lock Bar (11) from vertical to horizontal position, hinging 90 degrees at the Lock Bar Pivots (12). Resulting in Lock Bar (11) resting above A-Frame Steerable Draw Bar (9)

[0010] Driver inserts Lock-Bar to A-Frame Steerable Draw Bar Bolt (13) all the way down to Captive Nut (14) then tightens until firm. See fig 2 and 4.

[0011] Due to a potential situation when Tow Vehicle (1) is on a different horizontal plane relative to the Trailer/ Caravan Chassis (3) (For example, Tow Vehicle (1) level but Trailer Chassis (3) on an incline or decline), the incorporation of an Elongated Hole (21) in addition to Captive Nut (14) being able to slide in a sleeve will facilitate paragraph [0010] above. See fig 3

[0012]. These actions lock both the Front Turntable Steering Axis (18) horizontal plane movements plus the A-Frame Steerable Draw Steerable Pivot (10) vertical movements. Leaving only the required pivoting movements of Tow Ball Hitch (2).

[0013] Driver standing a safe distance from Trailer/ Caravan Chassis (3) will operate a convenient handheld remote to control the safe gentle extension of the Electric/ Hydraulic Cylinder Ram (7).

[0014] The effect of the Electric/ Hydraulic Cylinder Ram (7) extending outwards will force the connecting Bell Crank (5) to rotate through a forty- five degree arc supported by the Bell Crank Pivot (6).

[0015] Due to the Active Spare Wheel (4) completing the forty-five degree arc it will cause full wheel ground contact. In this fully lowered position which has simultaneously forced both front and rear Dog Trailer Wheels (8) to raise sufficiently causing loss of ground contact. See fig 2 and Fig 4.

[0016] When the driver uses the handheld remote control, it will have separate functions to apply the last two paragraphs [0014] and [0015] to one or both Electric/ Hydraulic Cylinder Rams (7). Thereby operating each Active Spare Wheel (4) raises one side individually or simultaneously raises both sides of the Trailer/ Caravan Chassis (3).

[0017] Due to variations of, [a] uneven ground contours below Tow Vehicle (1) and Trailer/ Caravan Chassis (3) or [b] variations in height of Tow Ball Hitch (2). The solution to level the Trailer/ Chassis (3) is needed to provide sufficient even ground clearance to all four Dog Trailer Wheels (8) to establish a level balanced Trailer/ Caravan Chassis (3) when both Active Spare Wheels (4) are fully lowered.

[0018] The solution is incorporated with another unique feature of this invention by turning the Front Draw Bar Pivot Levelling Handle (16) which will alter the angle of the Front Draw Bar Pivot (17) by up to ten degrees. In most situations, this will provide sufficient even ground clearance to all four Dog Trailer Wheels (8). See fig 2 and 4.

[0019] The driver can return to Tow Vehicle (1) and apply traditional single axle trailer skills to reverse and manoeuvre the Trailer/ Caravan Chassis (3).

[0020] When the Trailer/ Caravan Chassis (3) is in the completed park position, the driver will manually rotate the Front Draw Bar Pivot Levelling Handle (16) located on the Front Draw Bar (15), adjusting the potential ten degrees to zero degrees at the Front Draw Bar Pivot (17) to locking position.

[0021] The driver standing a safe distance from the Trailer/ Caravan Chassis (3) will operate the handheld remote, to control the safe gentle retraction of the Electric/ Hydraulic Cylinder Rams (7).

[0022] The effect of step 14) will force the connecting Bell Crank (5) to rotate through a forty-five degree arc, supported at the Bell Crank Pivot (6).

[0023] When the Active Spare Wheels (4) have completed the forty-five degree arc upwards, they will be no longer on ground contact but returned up into the Caravan Body (19).

[0024] The effect of steps paragraphs [0021], [0022] and [0023] will cause all four Dog Trailer Wheels (8) to make full ground contact. See fig 1.

[0025] Driver releases tension from Lock Bar (11) by unscrewing and removing Lock Bar to A-Frame Draw Bar Bolt (13) and raising Lock Bar (11) from horizontal to vertical position, pivoting approximately ninety degrees at the Lock Bar Pivot (12).

Driver reinstalls Lock Bar to A-Frame Draw Bar Bolt (13) horizontally to secure Lock Bar (11) into Caravan Body to Lock Bar Retainer Nut (20). See fig 1.

[0026] The Trailer/Caravan Chassis (3) can now be occupied for holiday/ leisure purposes, or alternatively ready for safe turning and highway use as a Steerable Turntable Dog Trailer Chassis supporting a caravan body. See fig 1 and 3.

Claims (5)

EDITORIAL NOTE 2021105791 THERE IS ONE PAGE OF CLAIMS ONLY Claims What is claimed is:

1. A steerable dog trailer caravan that uses Active Spare Wheels to allow a quick and easy and remote method of alternating between 4 wheel dog trailer and 2 wheel conventional caravan operations.

2. A steerable dog trailer caravan according to Claim 1 in which the Active Spare Wheels are moved by electrically or hydraulically operated rams.

3. A steerable dog trailer caravan according to Claim 1 in which the Active Spare Wheels are moved by high torque motors connected to the bell cranks.

4. A steerable dog trailer caravan according to Claim 1 that uses a Lock Bar in combination with a steerable Draw Bar.

5. A steerable dog trailer caravan according to Claim 1 that allows the caravan to be levelled on sloping ground.

EDITORIAL NOTE 18 Aug 2021

2021105791

THERE ARE TWO PAGES OF DRAWINGS ONLY