Portable stove

The present invention relates to a portable stove for burning multiple fuels comprising. The portable stove includes a burner body having a burner head, an exchangeable jet screwable into the burner head, a plurality of legs attached to the burner body, and a flame spreader detachably mounted on top of the burner head upstream the jet in the flame direction. The present invention is characterized in that the portable stove includes at least a second exchangeable jet screwable into the burner head, and the portable stove includes at least one mounting structure, wherein the second jet is supported within said mounting structure. The present invention is further characterized in that the flame spreader is attached to the portable stove with an elastic element.

FIELD OF THE INVENTION

The present invention relates to a portable stove. In particular, the present invention relates to a portable stove for burning multiple fuels.

BACKGROUND OF THE INVENTION

Commonly, such portable stoves comprise a burner body having a burner head, an exchangeable jet screwable into the burner head, a plurality of legs attached to the burner body, and a flame spreader detachably mounted on top of the burner head upstream the jet in the flame direction. When lighted, the flame emerges from the jet and hits the flame spreader where the flame is laterally distributed to obtain a planar heating of the cookware placed on top of the burner head. The legs are intended to have the portable stove stably resting on a surface or ground floor and can for instance be plugged to the burner body or be pivotally mounted to the burner body.

A portable stove as describe above is available as Primus® OmniFuel Stove. Said stove can be used with a plurality of different combustibles including gaseous combustibles like propane, butane or a mixture thereof, white gas, or liquid combustibles like vehicle petrol, kerosene or diesel oil. Hence, the stove can be used with nearly all combustible available worldwide. A schematic perspective view of the Primus® OmniFuel Stove is shown inFIG. 1with the portable stove being connected to a gas cartridge storing a gaseous combustible (FIG. 1a) and being connected to a fuel bottle storing liquid combustible (cf.FIG. 1b).

To ensure optimal flame patterns and a clean combustion, the jet mounted to the burner head has to be chosen to suit the combustible used. For instance, in case liquid fuel is used, a jet having a smaller size is to be mounted to the burner head compared to the jet to be used when a gaseous combustible is burned.

To exchange the jet, the flame spreader is detached from the burner head, and the jet currently mounted to the burner head is unscrewed. Afterwards the new jet is screwed to the burner head and the flame spreader is again mounted. For mounting and demounting the flame spreader, the latter one is provided with three mounting arms having catch mechanisms at the ends which engage the upper rim of the burner head. However, for mounting and demounting the flame spreader a lot of force is required. In addition, the catch mechanisms may be worn if mounted and demounted many a time. Thus, the flame spread might no longer be stably fitted to the stove or might even get lost during travelling.

Furthermore, in case the user is travelling for a long time and is not sure about the combustibles available in remote locations, several jets are to be taken with oneself. The jets are to be stored somewhere, e.g. in a storage container like a bag or a box or the like. However, in case the storage container is lost, only the jet currently screwed to the burner head is available. This might be crucial as using a non-suitable jet with the respective combustible may lead to sooting of the burner head rendering the portable stove unusable. In addition, a non-suitable jet does no longer ensure a clean combustion and hence, harmful compounds or gases may be formed, e.g. carbon monoxide.

Hence, the above outlined disadvantages might lead to inconvenient or even dangerous situations in case the portable stove cannot be used any longer due to a lost jet or a lost flame spreader or when the portable stove is used with a jet incompatible to the used combustible.

SUMMARY OF THE PREFERRED EMBODIMENTS

Accordingly, it is the technical objective of the present invention to provide a portable stove preventing the risk of losing essential parts of the portable stove.

The problem is solved with a portable stove according to claim1or claim5. Preferred embodiments of the present invention are disclosed and described in claims2to4and6to15.

The inventive portable stove as described in claim1is characterized in that the portable stove comprises at least a second exchangeable jet screwable into the burner head, and the portable stove further comprises at least one mounting structure, wherein the second jet is supported within said mounting structure. In other words, there is a structure suitable to receive a further jet and thus, the non-used jet can be stored together with the portable stove. As a matter of course, there can be more than one mounting structure provided with the portable stove. Thus, the non-used jets are no longer stored in a separate storage container, but are directly fitted to the portable stove. Hence, the jets cannot be lost.

According to an aspect of the invention, the mounting structure is disposed on one of said legs. Of course, the mounting structure can be provided on one leg or on any number of legs depending on the amount of jets to be carried together with the portable stove.

According to another aspect of the present invention, the mounting structure is an opening having an inside thread, wherein the second jet is screwed into the opening. The external thread provided on the jet for screwing it into the burner head further allows the jet to be screwed into the opening such that the jet is secured to the portable stove. The mounting structure may also be provided as a structure having an external threading in case the jets are provided with an internal threading.

According to a further aspect of the present invention which is also described in claim5, the flame spreader is attached to the portable stove with an elastic element. Thus, in case the flame spreader is demounted from the burner head, it cannot be lost as it is further attached to the portable stove. In addition, the elastic element provides a force sufficiently high to securely fix the flame spreader to the burner head. This in turn facilitates the mounting and demounting of the flame spreader, and further prevents wearing of the flame spreader.

According to a further aspect of the present invention, the flame spreader comprises a baffle plate and at least two mounting arms extending from the baffle plate. A first mounting arm is attachable to the burner head by a form-fit, and wherein a second mounting arm is attached to a first end of the elastic element. Thus, the flame spreader is attached to the burner head in that the form fit is established by catching the burner head with the respective catch mechanism provided at the end of the first mounting arm, wherein the force generated by the elastic element secures the flame spreader on the burner head. This arrangement greatly facilitates the mounting and demounting procedure of the flame spreader and further inhibits wearing as the mounting arms do not need to be elastically deformed for mounting and demounting the burner head. Of course, the flame spreader may comprise more than two mounting arms with at least two mounting arms being attachable to the burner head by a form-fit.

According to another aspect of the present invention, a second end of the elastic element is attached to the burner body. This allows the flame spreader to be easily mounted to and demounted from the burner head. In addition, the elastic element can be easily accessed and replaced if necessary.

According to another aspect of the present invention, the burner body comprises a wind shield surrounding the burner head, wherein the second end of the elastic element is attached to the wind shield. The wind shield ameliorates the flame pattern and inhibits a distorted heat transfer caused by wind.

According to another aspect of the present invention, the wind shield comprises a clearance on its upper end, wherein the second mounting arm is rests in the clearance when the flame spreader is mounted to the burner head. This facilitates the mounting of the flame spreader as only one possibility of mounting the flame spreader is possible. In addition, the second mounting arm cannot be laterally displaced which in turn inhibits the unintended separation of the flame spreader and the burner head.

According to another aspect of the present invention, the elastic element is an elastic tension element, preferably a helical tension spring. Helical tension springs are commonly available and thus, are inexpensive and can easily be replaced if out of function.

According to another aspect of the present invention, one of said jets is suitable for gaseous combustibles and wherein one of said jets is suitable for liquid combustibles. Thus, the portable stove can be used e.g. to prepare food or heat up water independently from the combustible available. This allows the portable stove to be used under a wide range of conditions.

According to another aspect of the present invention, the portable stove further comprises a multitool for screwing and unscrewing the jets into the burner head. Thus, the jets can be screwed to the burner head with a sufficient load. A sufficient load is mandatory to allow the portable stove to be operated adequately. In addition, it is preferable that the multitool can be secured to the portable stove when the portable stove is stored and not in use.

A specific embodiment of the invention will now be described below, by way of example, with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As can be seen from the Figures, the portable stove1is a multifuel portable stove1. Hence, it can be used with a variety of different combustibles. The portable stove1comprises a burner body2having a burner head3disposed within the burner body2. A jet4is screwed into the burner head3and a plurality of legs5are attached to the burner body2. In the embodiment shown, three legs5are attached to the burner body2in a hinged manner. A flame spreader6is mounted on top of the burner head3upstream of the jet4in the flame direction FD.

As can be seen fromFIGS. 2 to 4, the portable stove1further comprises a wind shield18surrounding the burner head3and a gas control23mounted within an inlet tube24for regulation of the combustible flow. The inlet tube24comprises a connection valve25and further opens out into the burner head3. A first end27of a hose26is attached to the connection valve25and a second end28of the hose26is connected to a shut-off valve29which can either be directly mounted to a cartridge21containing gaseous combustible (as shown inFIG. 1afor a prior art stove) or to a pumping device30, the latter one being connected to a fuel bottle22containing liquid combustible (as shown in.FIG. 1bfor a prior art stove).

The flame spreader6comprises a baffle plate10and three mounting arms11,13extending from the baffle plate10in the radial direction. Two of the mounting arms13are provided with catch mechanisms12at its ends which can be engaged to an upper rim portion7of the burner head3, as can be seen from e.g.FIG. 3. One mounting arm11is provided with a substantially perpendicular extending arm portion14at its end. When mounted to the burner head3, the arm portion14extends virtually parallel to the burner head3and has a mounting section15at its end. In the embodiment shown, the elastic element9is composed of a helical tension spring9which is mounted to the mounting section15with its first spring end16. The second spring end17is attached to the burner body2, in the embodiment shown to the wind shield18. As can further be taken fromFIG. 3, the wind shield18is provided with a clearance20at its upper end rim portion19and the mounting arm11with the arm portion14is resting within the clearance20when the flame spreader6is mounted to the burner head3(cf.FIG. 2).

To mount the flame spreader6, the flame spreader6is manually moved over the burner head3, therewith stretching the helical tension spring9such that a force is generated. Then, the two mounting arms13with the catch mechanisms12are attached to the burner head3such that a form-fit is established between the catch mechanisms12and the upper rim7of the burner head3. Next, the flame spreader6is lowered until the mounting arms13are supported on the upper rim7of the burner head3. As the helical tension spring9is not stress-free, but still expanded to some degree, the flame spreader6is pressed onto the burner head3and cannot separate therefrom. Unintended separation of the flame spreader6and the burner head3is further hindered as the mounting arm11with the arm portion14rests within the clearance20and lateral displacement thereof is inhibited.

To demount the flame spreader6, the above described procedure is reversed, i.e. the flame spreader6is manually lifted from the burner head3against the spring force and the catch mechanisms12are then disengaged from the upper rim7of the burner head3. As the helical tension spring9is permanently attached to the wind shield18with its second spring end17and to the flame spreader6with its first spring end16, the flame spreader6cannot get lost when demounted.

When the flame spreader6is demounted, the jet4screwed into the burner head3can be removed or exchanged respectively. Therefore, the portable stove1comprises a multitool31which can be brought into engagement with the mounted jet4. By turning the multitool31, the jet4is unscrewed from the burner head3and can be removed.

As can be seen fromFIG. 5one of the legs5of the portable stove1comprises two mounting structures8in form of openings8with inner threads. The jet4can be screwed into one of the openings8(cf.FIG. 6) such that it is securely fixed to the portable stove1. In addition, a second jet4which is now to be screwed into the burner head3can be unscrewed from the leg5. In general, three jets4are provided for the different combustibles used, namely one of the size 0.45 mm for cartridge gas (e.g. propane/butane mixture), one of the size 0.37 mm for white gas and one of the size 0.28 mm for liquid combustibles. As can be seen fromFIG. 6, two of the jets4are screwed into the respective opening8provided at one of the legs5of the portable stove1, wherein one of the jets4is screwed to the burner head3, the latter one being the one in use.