DE1782087B1 - GAS LIGHTER WITH A BURNER - Google Patents

Description

The invention relates to a gas lighter with a burner, which is in the direction of flow Gas one behind the other first a throttle device and then an evaporation device fed with liquefied gas is connected upstream, the path of the liquefied gas in the evaporation device by having good thermal conductivity with the lighter surface, especially one that is hit by the flame radiation Surface part, bounded heat transfer surfaces and in a variety of is divided at most partially connected parallel paths.

In such a lighter, the burner arrangement becomes, in addition to the burner, the throttle device and the evaporation device can also include a valve, fuel from the liquid phase supplied to the tank. Such a "liquefied gas burner" is in contrast to such Burner arrangements that are fed from the vapor phase of the fuel and one for the passage of steam designed throttle device, and has the advantage that no fillers, such as felt, with their known disadvantages, are needed. From the fact that the heat of vaporization of liquid gas around 100 cal / g, whereas the specific heat of liquid gas is only 0.6 cal / g ° C, it follows that the area around the evaporation zone is inside the burner assembly must cool down sharply, if the liquid gas conveyed to the evaporation zone is not quite is warm. This results in the well-known difficulties of the "liquefied gas burner", which are particularly with a small temperature difference between the boiling temperature and the liquid gas temperature and at have an effect with a large flame and in general

common at low ambient temperatures, i.e. especially in winter, are quite uncomfortably noticeable.

There are known constructions in which a porous sintered body made of plastic, ceramic or metal forms the input of the burner assembly and both the throttling and the evaporation should serve. However, this structure leads to a very restless flame, as the throttling effect depends on at which point of the porous body the evaporation takes place and this point depends on from numerous influences, especially the temperature, changes. Besides, it prepares Difficulties in arbitrarily adjusting the throttle (U.S. Patent 3 327 504, F i g. 1 to 3). Similar relationships apply to a burner in which a porous metal body has both the throttling as well as the evaporation is to be used and in this case compressed to adjust the throttling can be (German patent specification 1 028 366).

Furthermore, lighters with liquefied gas burners are known in which in one to close to Bottom of the tank reaching housing insert above a throttle device in the form of a needle valve and underneath a porous sintered body made of plastic or metal oxide, such as iron oxide, as an evaporation device are located. The porous body is completely enclosed in the housing insert; his Surface is only exposed at the bottom and over a small area of the top. One such a burner arrangement fails at low temperatures. The amount of heat required for evaporation is namely withdrawn from the liquid gas and the environment, so that in the evaporation body a temperature drop of 5 to 10 ° C occurs. But since normal butane has a vapor pressure at - 0.5 ° C of 1 atm, the evaporation stops or deflagrated liquid droplets are released the burner off as soon as the ambient temperature is between 4.5 and 9.5 ° C. This disadvantage can one can counteract by adding isobutane and propane, as is usually the case; it occurs but then an increasing segregation of the tank contents with progressive flame unrest (USA.-Patent 3,286,491).

In other designs, both throttling and evaporation were done with the help of a Wicks carried out. For example, the throttle device was made by a compressible Ring area of the wick formed while evaporation on the surface of the inside of the ring area remaining, less compressed wick part should be done. The compression takes place with the help of a pressure piece carrying the valve seat and having an outlet channel, which is thermally connected to the surface of the burner. Here, the throttle point is heat supplied, which leads to an early evaporation, while at least at low ambient temperatures the evaporation body »freezes« within the ring area and thus the evaporation exposes (German Auslegeschrift 1114 352). The same applies to a construction in which the outlet channel in the pressure piece is fitted with a wick or fiber plug is filled (German Auslegeschrift 1153 562).

In other known constructions, a continuous wick initially penetrates a perforated one elastic body and then a valve seat supporting, thermally connected to the burner surface Pressure piece. The latter is able to deform the elastic body in such a way that the wick in the Hole is compressed more or less strongly and thereby an adjustable throttling takes place. Here, too, evaporation stops at low ambient temperatures (Austrian patent specification 222403, Swiss patent specification 413 465).

Then a liquid gas burner is known in which a throttle device in the form of a compressible porous ring body followed by an evaporation device in the form of an annular gap which is limited by metal surfaces that are in thermal contact with the top of the burner will. One wall of the gap is profiled, for example provided with a thread. These However, construction only makes sense for a very low, practically unusable flame height. Will be a If a larger flame is set, it is very restless due to twitching and puffing. Apparently be through large gas bubbles that form in the annular gap, liquid particles in front of them are thrown outwards (French patent 1481 942).

A petrol lighter with a wick has also become known, in which the liquid fuel is sucked up to the burning point without throttling. The part of the wick protruding into the atmosphere consists of fine metal wires so that the end of the wick does not burn (French patent specification 1 263 647).

The invention is based on the object of specifying a gas lighter with a liquid gas burner which works safely even at low ambient temperatures and under all operating conditions with a quiet, even flame burns.

Based on the gas lighter mentioned at the beginning, this object is achieved according to the invention solved that each parallel path over at least part of its length through heat transfer surfaces is limited.

With this construction, the liquid gas to be evaporated is drawn from the surface of the lighter So much heat is supplied via the heat transfer surfaces that hardly any significant amount of heat occurs during evaporation Temperature drop occurs. Nevertheless, this supply of heat does not result from the formation of gas bubbles restless flame. It is true that in the present case, too, it can be assumed that the Heat transfer surfaces gas bubbles arise; however, these occur in the multitude of parallel paths not at the same time, but statistically distributed. Also, they have an extremely small volume, like that that overall a very stable, calm flame results. This material of the evaporation device also differs from the material of the upstream throttle device, which is in the usual way consists of a poorly thermally conductive material, so that there is no or at most insignificant Evaporation occurs.

In a particularly advantageous embodiment, the evaporation device has at least one The porous layer completely penetrating the cross-section of the liquid gas path flowing through it a material with good thermal conductivity and a thermal conductivity of at least 10, but preferably

over 50 kcal / m, h. ° C. This layer defines the Evaporation zone, where a sufficient supply of heat is possible in each parallel path.

The layer of material with good thermal conductivity can be part of a porous evaporation body. Of the However, porous evaporation bodies can also consist entirely of the material, which is a good conductor of heat.

It is most favorable if the material that conducts heat well is a metal with a thermal conductivity of over 100 kcal / m, h. ° C is. In particular, it can be copper.

There are various options for the structural design. For example, it can do that well thermally conductive material can be sintered into the desired shape. With another simple construction it is a single or multi-layer wire mesh. Suitable fine-mesh wire mesh are commercially available in various weaves and materials for filter purposes. Furthermore, a Good heat-conducting layer also through a metallization of a porous body through galvanic Order or made by flame spraying.

To ensure that the evaporation actually takes place within the evaporation device takes place, this should have a flow resistance that is no more than 10% of the flow resistance the throttle device is. It is particularly favorable here if the evaporation device is formed by a substantially disk-shaped evaporation body. This form results a large number of parallel paths of limited length, so that the desired low flow resistance is easy to get to. The thickness of the pane is determined by the amount of heat required for the evaporation body is available. A large radiation absorption surface on the top of the burner and a low heat transfer resistance inside of the burner thus allows a small slice thickness.

In a further embodiment of the invention, essentially the entire surface of the exit end face of the disk should be exposed. In this case you can all parallel paths open into an adjoining gas collection room. However, this gas collection room should be as small as possible, so that there are no significant ones when the burner valve is closed Liquefied gas quantities collect when the gas dew point is undershot and pop up when the valve is opened can relax. In particular, the exit face of the disc can face a slightly conical wall, in the middle of which an outlet channel goes off. The gas collection space can also be formed thereby be that the disc has a circumferential bead on at least one end face with which it is at a short distance from the adjacent housing wall.

Sometimes it is advisable to enlarge the exit surface even more, by as many as possible To have outputs from the parallel paths available. This can be done by the evaporation body is conical at the exit face. The evaporation body can also be axial Have extension that extends into the central outlet channel. That way, when the The outlet channel is closed by a valve, the gas collection space is kept to a minimum.

In a further embodiment of the invention, it is proposed that the inlet end face of the evaporation body essentially cover its entire surface of a compliant porous material to contact. This material can e.g. B. non-woven paper be. This ensures that all parallel paths are supplied with liquid fuel and contribute to evaporation. In particular, the aforementioned material can be replaced by the material of the upstream Be formed throttle device.

According to a further aspect of the invention, the upstream throttle device is opposite to the Thermally insulated evaporation device. This ensures that the throttling that occurs Lowering the temperature does not have a detrimental effect on the intended supply of heat to the evaporation device Has.

The application of the principle of the invention to a lighter in which the Burner assembly is inserted into a plastic tank. A plastic tank does not conduct heat well. Therefore are the disadvantages of incomplete evaporation at low temperatures, described at the outset even more pronounced. With the help of the invention it is possible for the first time to have a usable liquid gas burner can also be used for a lighter with a plastic tank.

The invention is explained in more detail below with reference to the exemplary embodiments shown in the drawing explained. It shows

Fig. 1 is a schematic side view of a lighter, which can be designed according to the invention,

F i g. 2 shows a longitudinal section through the lighter part having the burner arrangement in a first Embodiment,

F i g. 3 shows a longitudinal section through the part having the burner arrangement in a second exemplary embodiment and

F i g. 4 to 9, in partial longitudinal sections, various exemplary embodiments of an evaporation body.

The lighter of the F i g. 1 has a tank 1 which is surrounded by a metal sleeve 2. An essay 3 carries a push button 4, when actuated the ignition cap 5 goes up and at the same time an ignition wheel is rotated to generate an ignition spark. A burner arrangement 6 is located in the top of the tank screwed in, which will be described in more detail later. In the bottom there is a nozzle 7 with a Filling valve.

In Fig. 2 shows a burner assembly in its closed position. The arrow 8 indicates that of the Closing cap 5 exerted closing force. In a thread 9 of the tank 1 is with the interposition of a Seal 10, a housing 12 closed at the bottom by a base 11 is inserted. Into a thread 13 A throttle actuator 14 is screwed into this housing 12, which is connected to the outside by means of a toothing 15 Handwheel 16 carries, which is secured by an elastic disc 17 against falling. At the inside of the actuator 14 is a tubular burner 18, which against the force of a spring 19 in a Telescopic member 20 is displaceable. The telescopic member presses down on a valve disc 21, which is in the The closed position rests on a valve seat 22. A compression spring 23 assists the lifting of the valve disc 21. The function of such a burner is known. .

The valve seat 22 is formed on an insert 24 in a recess 25 on the underside a disc-shaped, porous evaporation body 26 made of a material that conducts heat well, which is attached to its circumferential surface is connected to the insert 24 in a thermally conductive manner. The exit end face 27 of the evaporation body 26 has a substantially exposed surface. Your face is a slightly conical one Wall 28 of the insert opposite, which leads to a central outlet channel 29.

The underside of the insert 24 presses on an elastic sealing ring 36. Inside the ring 36 and between the ring and the base 11 is a throttle body 30, which in the present case consists of three parts 31, 32 and 33 consists, which can have different porosity. The material can for example be a porous, rubber-elastic crosslinked polyurethane.

If the actuator 14 is screwed down by means of the handwheel 16, the seal 36 ao pressed downwards and deformed inwards, so that the entire throttle body 30 is compressed radially or axially will. This allows the throttle resistance and thus the height of the flame to be adjusted.

In the bottom 11 there is a central opening 34. A plug 35 made of porous material is attached to it on, through which liquid gas is passed from the lower part of the tank to the throttle body 30 can be.

When the valve 21, 22 opens after the cap 5 has been lifted off, liquid gas penetrates as a result of the pressure drop through the throttle body 30 into the evaporation body 26. The evaporation occurring there is supported by the supply of heat, which is transferred to the parts 14, 16 by flame radiation and then transferred to the highly conductive evaporation body 26 via the insert 24. That then escaping gas results in a very even flame even at low ambient temperatures.

The embodiment of FIG. 3 uses essentially the same elements as in FIG. 2. It the same reference numerals are therefore used. However, this time the tank 41 is made of plastic formed, in addition, the burner arrangement +5 voltage receiving housing 42 with a thread 43 is made of plastic and molded onto the tank 41 as a nozzle. The seal 10 are not applicable. The sealing ring 36 prevents the fuel from escaping while bypassing the Valve 21, 22. Since the plastic of the tank 41 is a poor conductor of heat, and so is the sealing ring 36 as well as the throttle body 30 are poor heat conductors, the effect that occurs during throttling There is hardly any cooling on the evaporation body 26 made of a material that conducts heat well. This receives but conversely, via the actuator 14, sufficient heat from that exposed to the flame radiation Top of this actuator. As a result, the evaporation in the body 26 is caused by the throttling effect not disabled. Conversely, the heat supplied to the throttle body because of the insulated Arrangement of the throttle body 30 does not lead to undesired evaporation already in the throttle body to lead.

In Fig. 4 shows a part of a modified insert 24 which has a two-stage in its underside Has recess 50, in which a disk-shaped, porous evaporation body 51 made of sintered Copper is used in such a way that it is with its periphery and part of its top on the metal of the insert 24, but the essential part of its upper surface freely facing a gas space 52 is.

In the embodiment of FIG. 5, the insert 24 has only one cylindrical recess 53, in which a sintered body 54 is inserted which has the shape of a disk with a bead 55 on both Has sides, so that in turn a gas space 56 results.

In the embodiment according to FIG. 6 is a sintered body (evaporation body) 57 as an evaporation body provided, the a disk-shaped part 58, a conical part 59 and an axial extension 60 has. Correspondingly, the recess 61 in the insert 24 is also provided with a conical surface 62, which merges into the outlet channel 29, so that a very small gas space 63 results.

In Fig. 7, an insert with a cylindrical recess 64 is illustrated. A porous sintered body 65 is covered with an upper layer 66 and a lower layer 67 made of non-woven paper.

Tn F i g. 8 is in a cylindrical recess 68 of the insert 24 single or multi-layer wire mesh 69 and a layer 70 of non-woven paper arranged one above the other.

In Fig. 9, a layer 72 of non-woven paper is provided in a cylindrical recess 71, which is shown in FIG a layer 73 is metallized.

In all embodiments it is ensured that the highly thermally conductive material that is transverse extends to the direction of flow through the evaporation body, good thermal conductivity with the insert and therefore communicates with the top of the burner assembly. This can be achieved by a press fit of the Easily reach the evaporation body in the insert 24. A wire mesh as an evaporation can also be used for Improvement of the thermal contact formed into a bowl, clamped in like a membrane, soldered in or welded on be.

1 sheet of drawings 209 522/88

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Claims (18)

Patent claims: 1. Gas lighter with a burner, one behind the other in the direction of flow of the gas upstream of a throttle device and then an evaporation device fed with liquefied gas is, wherein in the evaporation device the path of the liquefied gas through good thermal conductivity with the lighter surface, especially one hit by the flame radiation Surface part, bounded heat transfer surfaces and in a variety of is divided at most partially connected parallel paths, characterized in that that each parallel path passes through heat transfer surfaces over at least part of its length is limited. 2. Gas lighter according to claim 1, characterized in that the evaporation device at least one completely penetrating the cross section of the liquid gas path flowing through porous layer (26, 51, 54, 57, 65, 69 72) made of a highly thermally conductive material with a Thermal conductivity of at least 10, but preferably more than 50 kcal / m, h. ° C. 3. Gas lighter according to claim 1 or 2, characterized in that the layer of good thermally conductive material is part of a porous evaporation body (26, 51, 54, 57, 65). 4. Gas lighter according to claim 3, characterized in that the porous evaporation body (51, 54, 57) consists entirely of the material that conducts heat well. 5. Gas lighter according to one of claims 1 to 4, characterized in that the material with good thermal conductivity is a metal with a thermal conductivity of over 100 kcal / m, h. ^{c is} C, preferably copper. 6. Gas lighter according to one of claims 1 to 5, characterized in that the good heat conducting Material is sintered. 7. Gas lighter according to one of claims 1 to 5, characterized in that the highly thermally conductive Material is a wire mesh (69). 8. Gas lighter according to one of claims 1 to 7, characterized in that the evaporation device has a flow resistance which is at most 10% of the flow resistance of the throttle body (30). 9. Gas lighter according to one of claims 1 to 8, characterized in that the evaporation device is formed by a substantially disk-shaped evaporation body (26, 51, 54, 65). 10. Gas lighter according to claim 9, characterized in that substantially the entire Surface of the exit end face of the disc (51, 54) is exposed. 11. Gas lighter according to claim 10, characterized characterized in that the exit end face of the evaporation body (26) is slightly conical Opposite wall (28), in the middle of which an outlet channel (29) goes off. 12. Gas lighter according to one of claims 9 to 11, characterized in that the body (54) has a circumferential bead (55) on at least one end face. 13. Gas lighter according to one of claims 3 to 12, characterized in that the evaporation body (57) is conical on the outlet side is. 14. Gas lighter according to one of claims 3 to 13, characterized in that the evaporation body (57) has an axial extension (60) which extends into the central outlet channel (29) extends. 15. Gas lighter according to one of claims 3 bisl4, characterized in that the inlet end face of the evaporation body (26, 65) in the essentially over its entire surface of a flexible, porous material (31, 67) is contacted. 16. Gas lighter according to claim 15, characterized in that the contacting the entry end face, Resilient, porous material due to the material of the upstream throttle device (30) is formed. 17. Gas lighter according to one of claims 1 to 16, characterized in that the upstream The throttle device (30) is thermally insulated from the evaporation device (26) is. 18. Gas lighter according to one of claims 1 to 17, characterized in that the burner arrangement (6) is inserted into a plastic tank (41).