Technical Field

The object of the invention is an amphibious vehicle with a living compartment, which is towable by a land vehicle, preferably an amphibious caravan.

Background Art

Spending the holidays and leisure time on water or on the beach is getting increasingly popular, using boats on the water and caravans on land. The parallel use of a boat and a caravan that are each big enough to contain a living compartment poses the problem that at least two cars are needed to tow them. Also due to the relatively high price of a boat and a caravan, several solutions have been suggested to combine these two, to save costs and storage space, which would be otherwise necessary for an independent boat and caravan.

A known solution is described in DE 2 238 786 Al, with an amphibious caravan having broadened buoyancy tanks to increase the stability of the floating caravan. This solution does not provide means to transport the towing vehicle with the caravan on the water. DE 2 239 981 Al teaches a similar solution, with the same problem of the towing vehicle remaining. This means that the route of the trip on the water must be planned with the same place for embarking and disembarking, in order to return to the place where the towing land vehicle have been left behind. A further disadvantage that the towing land vehicle is left behind unprotected, or it must be parked in a protected, but thus expensive parking place. Also, the sport and camping equipment transported in the baggage compartment of the towing land vehicle - normally the family car - must be packed out and transferred to the caravan. Also, the caravan itself must be provided with an engine, which should be strong, economic, quiet and environmental friendly. It would be of advantage if this extra cost could be saved.

An other solution to convert a known minibus into an amphibious vehicle is described in US 3,933,112. This „road boat" comprises a removable roof-boat and sealing subsections to waterproof the underside of a known land vehicle, and water jet means propelled by the engine of the land vehicle. A disadvantage of this known solution is the complicated fitting and assembly of the waterproofing means with the standard land vehicle. Also, most families prefer to have a larger caravan with the towing car, instead of a smaller, but self propelled caravan. A large caravan and a towing car offers in many cases more comfort and also more flexibility, enabling the users to leave the bulky caravan behind on short one-day trips or when just doing the daily shopping.

A further solution is suggested by US 4,013,029. This patent specification teaches the construction of a water vessel supporting a land traversing vehicle, such as a motorcycle or a snowmobile. The water vessel is provided with propulsion means connected to the power output device of the land vehicle. The size of the water vessel is such that it is capable of being towed by the very same land vehicle that it is supporting.

The same approach may be found in DE-OS 1 926 726. However, neither of these solutions do teach the including of a living compartment in the water vessel or the land vehicle.

A further solution is described in DE 30 49 833 Al, where means are provided to convert a conventional self-propelled caravan into a sea-faring vehicle. Similarly to US 3,933,112, the assembly of this amphibious caravan is very complicated, because the hull of the amphibious vehicle is constructed of several parts, that must be fitted together in a water-tight manner.

Hence, the aim of the invention is to provide an amphibious vehicle that is capable of movement on land roads and on the water, and at the same time provides temporary living space for a family. The invention should at the same time allow

the free planning of the water route, and offer a solution to the problems mentioned above, i. e. it should be easy to handle and operate.

Summary of the Invention

According to the invention, the aims above are realised with an amphibious vehicle with a living compartment, which is towable by a land vehicle, preferably an amphibious caravan. The amphibious vehicle of the invention comprises a compartment that is capable to contain a land vehicle, preferably the land vehicle towing the amphibious vehicle.

According to a preferred embodiment, the vehicle of the invention comprises propelling means, and the propelling means is driven by the engine of the towing land vehicle. Advantageously, the vehicle is constructed to accommodate additional living space, preferably a tent. In a further preferred embodiment, the vehicle of the invention further comprises a ramp rotatable around a horizontal axis to facilitate the boarding ofthe land vehicle.

To provide extra space for the usual recreational activities on the water, it is foreseen that the vehicle further comprises side platforms rotatable around a horizontal axis close to the water level. This means that the actual watertight hull of the vehicle may be kept relatively high, in order to increase safety of the vehicle, but at the same time there is a platform for the users of the vehicle close to the water level, so the bathing or fishing may take place from these platforms. To save space on land, the platforms may be rotated around their axis to close them to the side ofthe amphibious vehicle.

For further convenience, the vehicle may comprise a sunbathing platform, placed on the top ofthe vehicle or at an other elevated position.

To utilise the vehicle better, it is advantageous if the compartment receiving the land vehicle is also capable of storing water recreational equipment.

If the amphibious vehicle is propelled by the engine of the towing land vehicle, control of the engine is simpler if the vehicle is operable from the driver's seat of the land vehicle when the land vehicle has boarded. However, the transmission of the steering from the land vehicle may pose technical problems, so a remote controlled steering may prove more feasible.

To protect the wheels from water, and the water from oil pollution, it is foreseen that the wheels are retractable into a watertight compartment when the vehicle is on the water.

In a preferred embodiment, the transmission from the engine of the land vehicle to the propelling means is a mechanical one. But it is also feasible that the transmission from the engine of the land vehicle to the propelling means is a hydraulic one.

Brief Description of Drawings

By way of example only, an embodiment of the invention will now be described with reference to the accompanying drawing, in which

Fig. 1 is a schematic cross section of the amphibious vehicle of the invention together with the towing land vehicle.

Best Mode for Carrying out the Invention Fig. 1 shows the amphibious vehicle 1 of the invention, with the towing land vehicle 2 firstly in the towing position, secondly in the position for voyage on water. The amphibious vehicle 1 is fitted with a land vehicle compartment 3, that is big enough to contain fully the towing land vehicle 1. At the rear, there is an upper deck 4 with a fixed construction, where the living comfort facilities of the amphibious vehicle 1 are installed. The upper half of the sides may be extended, so together with the top there is an extendible upper part 5, providing extra living room

for the users of the amphibious vehicle 1. In a known manner, the extendible upper part 5 may have a tent-like construction as well. Windows 8 may be included in the sides ofthe tent or the extendible side walls. The extendible upper part 5 is retracted during transport on land.

The main dimensions of the amphibious vehicle 1 are defined partly by the land vehicle 2 to be included, partly by the constraints of land traffic. In a preferred embodiment, the width may be 2,45 m, the length between 6 and 9 m, height 2,4 m. at the rear (or front), and 1,9 m in the front (or rear). The height with fully extended extendible upper part 5 may reach 3,6 m. With full load, the draught may be 0,5 m. Obviously, the towing land vehicle 2 must be placed as low as possible, to enhance the stability ofthe amphibious vehicle 1.

Preferably, the amphibious vehicle 1 is supported on land by four wheels 11 with independent suspension, which are retractable into watertight compartments (not shown) on the water. The towing vehicle 2 rolls into the land vehicle compartment 3 on a ramp 6, this latter rotatable around a horizontal axis. The whole unit than may be rolled into the water on the wheels 11, or - where applicable - the unit may be pulled into the water using an anchor and a winch (not shown).

In order to save the extra costs for a separate engine for the amphibious vehicle 1, the engine of the towing vehicle 2 may provide the necessary power to drive the propelling means of the vehicle, preferably propeller 10. The transmission from the engine may take place with a mechanical transmission using a pair of rollers 7 under the driven wheels of the towing land vehicle 2, in a manner known itself. Depending on the size and shape of the two vehicles, a hydraulic transmission may be utilised as well.

In case the engine of the towing land vehicle 2 is used as a power source, the most natural solution to operate the amphibious vehicle 1 is sitting in the driver's seat of the towing land vehicle 2. The steering may take place via the steered wheels, but a

remote controlled steering system, e. g. an electrically actuated mechanism controlled by a joystick via a cable, is also possible. The driver may look out from the land vehicle compartment 3 through the windows 9.

Hence, the invention provides an amphibious vehicle 1 that offers several advantages. The amphibious vehicle 1 together with the towing land vehicle 2 constitutes a transport unit which is fit for transport (and stay) on land or water, with simple transformation and assembly, and at the same time allows for the free and unlimited selection of the route on land or water. At the same time transfer of luggage and other equipment is not necessary from one transport means to the other. Because the transport unit is propelled by the engine of the towing land vehicle 2, the cost of a second engine is saved. Considering that modern car engines are both economic and environment-friendly, these beneficial properties will apply on the water as well.