Simple spirit lamp

Abstract

Very simple wick lamps are used for decorative purposes. They consist of a metal can and a cover with a wick and are fuelled by paraffin oil. The flame burning on the wick is luminescent because it forms soot particles that are excited to luminesce. However, soot is also emitted into the environment. This is undesirable. If such a lamp is fuelled with ethanol or methanol, it does not produce soot, but it also does not produce a luminous flame. When using a wick lamp, it is not possible in place of soot to introduce light-emitting metal atoms into the flame using an alcohol-based solution of metal salts as fuel. 2.2 The simple spirit lamp produces a soot-free flame that is made to luminesce by excited alkali metal atoms. An ethanolic or methanolic solution of alkali salts is used as the fuel. The simple spirit lamp has a burner head that consists of at least one burner cup with heat conductors that extend into the hot outer zone of the flame. The alkali salt dissolved in the fuel enters the flame because the fuel boils in the burner cup and small droplets are produced that are carried by the fuel vapour into the flame. The simple spirit lamp can have an unregulated or a self-regulated supply of fuel. The embodiment with a regulated supply of fuel consists of the tank (1), the burner cup (2) with heat conductors (2.1), the inner burner cup (3) with inner heat conductors (3.1), the riser tube (4) and a sealing ring (5). 2.3 Production of decorative, non-sooting, luminous flames in different colours.

Description

[0001] Title of the invention

[0002] Simple spirit lamp

[0003] Description

[0004] The invention described in this patent specification relates to lamps with a luminous flame that are operated with a liquid fuel.

[0005] The simple spirit lamp according to the invention is preferably operated with methanol or ethanol as fuel containing dissolved alkali formates. To prevent poisoning that could result from accidentally drinking the fuel as a beverage, the fuel must be rendered unfit for consumption with a suitable denaturant, for example, butan-2-one. The simple spirit lamp is designed such that the metal salts dissolved in the fuel are carried to the flame and cause it to glow.

[0006] Simple oil lamps with wicks have been known since antiquity. They consist of a container for a liquid fuel (e.g., vegetable oil) with a small opening for a wick, on which a luminous flame burns. Lamps with a similar, very simple design are still in use today. In these simple wick lamps, a tin can serves as the tank. It is sealed by a lid with a hole through which a wick is threaded. Oil lamps of this type are usually fueled with paraffin oil and used outdoors, for example at garden parties, for decorative purposes. A technically more advanced version of the simple wick lamp is the kerosene lamp, equipped with a glass windscreen, which is also still in use.

[0007] In these types of lamps, both the simple wick lamp and the kerosene lamp, the desired effect, the light, is caused by the presence of soot particles in the flame. The soot is produced in the flame as a result of the incomplete combustion of the fuel. Although some of the soot particles are destroyed within the flame itself, a certain portion remains and leaves the flame with the exhaust gas.

[0008] The soot buildup from a wicked kerosene lamp isn't always readily visible. However, if you hold a glass pane close to the lamp, a black deposit will form on the pane within just a few seconds. This makes the soot formation obvious. The soot buildup from simple wick lamps fueled by paraffin oil is significantly greater. It's so substantial that using them indoors is usually out of the question. The soot isn't just an aesthetic problem, but also a health hazard, as it's carcinogenic.

[0009] Soot production from flames can be drastically reduced when ethanol is used as fuel. An even smaller amount of soot is produced when methanol is burned. However, the flames produced with methanol are very dim due to the absence of soot. This disadvantage can be overcome by introducing small amounts of alkali formates into the flame. For example, the presence of sodium in the flame produces an intense orange flame, while the presence of lithium produces a red flame. The flame's exhaust now contains fine dust particles consisting of alkali carbonate instead of soot. However, these are considerably less problematic than the soot-based fine dust particles from a kerosene lamp flame or a paraffin-fueled wick lamp flame without a wind guard. They do not adhere to the surfaces of walls or objects like soot particles, but can be easily removed by vacuuming.They are also not carcinogenic, unlike fine dust particles from soot.

[0010] Using a conventional simple wick lamp or a kerosene lamp and an alcoholic solution containing alkali salts as fuel, it is not possible to produce ethanol or methanol flames that are ignited by the presence of alkali atoms. While the alkali salts dissolved in the fuel are indeed drawn to the top of the wick along with the fuel, only the alcohol evaporates there, with the burning alcohol vapor forming the flame. The alkali salts, on the other hand, are deposited as crusts on the wick and do not enter the flame.

[0011] This is where the invention comes in, the aim of which is to produce flames colored by alkali metal salts using a device as simple as a basic wick lamp or a kerosene lamp. A high degree of user safety should also be guaranteed.

[0012] Combustion experiments with methanolic and ethanolic alkali-salt solutions led to the discovery that sufficient quantities of alkali metal salts enter the flame to illuminate it when the flame burns above a cup or bowl and the solution boils beneath the flame. The transport process that carries the alkali metal salts into the flame occurs when bubbles in the boiling fuel burst, forming tiny droplets of the alkali-salt solution. These droplets are then carried into the flame by the flow of fuel vapor rising from the surface.

[0013] To vaporize the amount of fuel required for the desired flame size through boiling, a specific amount of heat must be transferred to the combustion chamber. Investigations revealed that the radiant heat emitted by the flame into simple, small, filled bowls or cups is usually insufficient for this purpose. While enough fuel evaporates to sustain a flame, boiling with droplet formation does not occur. Sufficient boiling, however, could be achieved when heat-conducting components, such as sufficiently thick metal wires, were mounted in the cup so that they extended from the hot outer zone of the flame into the liquid within the cup, or when a metal container with heat-conducting strips around its rim was used as the combustion chamber.

[0014] As a result of inventive efforts, this patent describes a novel, simple spirit lamp. It consists of a small tank 1, on the top of which a torch head is located. The torch head is supplied by a riser pipe 4 that begins at the bottom of the tank. According to the invention, it is proposed that

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[0019] The simple spirit lamp is put into operation by first filling tank 1 with an amount of fuel less than half its volume and then sealing it. The lamp is then held at an angle, and one of the heat conductors 2.1 or the upper edge of tank 1 is heated with a lighter. This heats the upper part of tank 1, and a slight overpressure builds up in the gas mixture of air and fuel vapor in the upper part of tank 1. The lamp is then stood upright. As a result of the overpressure, fuel is forced from the lower part of tank 1 up through the riser 4 into the combustion chamber 2. It is then ignited with the lighter. Sufficient heat is conducted from the heat conductors, which extend into the hot outer zone of the flame, to the combustion chamber 2 to bring the fuel in it to a boil. The fuel vapor produced during boiling feeds the flame.To prevent the combustion cup 2 from overflowing when operating the simple spirit lamp, the riser pipe 4 must have sufficient flow resistance.

[0020] This simple spirit lamp design has the advantage of being particularly simple in construction and therefore very inexpensive to manufacture. However, it also has the disadvantage that the fuel flow rate supplied to the combustion chamber 2 is not regulated. As a result, the fuel flow rate is not constant during operation. It is highest when the simple spirit lamp has just been switched on and then decreases because the gas in the upper part of the tank 1 gradually expands, causing the pressure to drop. The combustion chamber 2 and the heat conductors 2.1 can certainly be designed so that the combustion chamber 2 does not overflow even at the higher fuel flow rate immediately after starting the lamp. However, it is undesirable that the flame is larger at the beginning of operation due to the varying fuel flow rate and then becomes significantly smaller.Another goal of the inventive efforts was therefore to develop a device that ensures the fuel delivery rate remains constant. The result is a simple spirit lamp with a regulated fuel supply, in which...

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[0025] In this way, a simple control device is created that automatically adjusts the required fuel flow rate and also compensates for deviations in the delivery pressure due to outside temperature.

[0026] The simple spirit lamp with regulated fuel supply is also put into operation by first filling the tank 1 with a quantity of fuel that is less than its total internal volume and sealing it. The simple spirit lamp is then held at an angle, and one of the heat conductors 2.1 or the upper edge of the tank 1 is heated with a lighter. This heats the upper part of the tank 1, and a slight overpressure builds up in the gas mixture of air and fuel vapor in the upper part of the tank 1. The simple spirit lamp is then stood upright. As a result of the overpressure, fuel is forced from the lower part of the tank 1 upwards through the riser 4 into the inner combustion chamber 3. It is then ignited with the lighter.

[0027] The now burning flame heats the heat conductors 2.1 and the inner heat conductors 3.1. The inner heat conductors 3.1 heat the inner combustion chamber 3, causing the fuel within it to boil intensely. The heat conductors 2.1 conduct heat energy from the hot outer surface of the flame to the combustion chamber 2. The combustion chamber 2 heats up to above the boiling point of the fuel. Heat is then transferred from the combustion chamber 2 to the upper part of the tank 1. This further increases the temperature of the air trapped there, resulting in an increased flow of fuel upwards. Consequently, the fuel level in the inner combustion chamber 3 rises until it overflows. The overflowing fuel flows into the combustion chamber 2 and cools it through the heat of vaporization extracted from the boiling fuel that has entered it.This reduces the heat transfer to tank 1, the pressure decreases, and consequently, so does the fuel delivery rate. This results in a self-regulating fuel supply system.

[0028] The automatic regulation of the fuel flow rate functions correctly only if a temperature increase in the air trapped in the upper part of the tank also results in a pressure increase. This is only the case if the riser pipe 4 has sufficient flow resistance. This can be ensured by designing the riser pipe 4 as a capillary or, if the riser pipe 4 has a larger inner diameter, by incorporating a flow resistance element 10. For operational safety reasons, the temperature of the fuel in tank 1 should always remain below the boiling point corresponding to the ambient pressure. If this is not the case, a safety risk arises because, when the tank 1 cap is opened and the resulting pressure drop occurs, the fuel will foam due to delayed boiling.The resulting increase in volume would cause fuel to leak out, even with tank 1 correctly positioned, thus creating a fire hazard. Therefore, a simple spirit lamp is typically designed so that the temperature of the fuel in the tank always remains below its boiling point.

[0029] To prevent rapid fuel leakage through a leak in tank 1, for example, caused by a manufacturing defect, the maximum internal pressure in tank 1 should be kept as low as possible. The simple spirit lamp should therefore be designed so that the internal pressure does not exceed 60 hPa above ambient pressure during normal operation. The simple spirit lamps according to embodiments 3 and 4 are also equipped with an additional pressure relief device.

[0030] As a further safety measure, the tank 1 used in the embodiments is designed in such a way that the fuel contained therein cannot leak out quickly even if the tank 1 is knocked over or turned upside down with the closure open.

[0031] During development work, it became apparent that alkali formates are best suited as additives to the fuel of a simple spirit lamp for the intended purpose: to make the almost colorless flames of burning methanol or ethanol glow. Glowing flames can also be achieved by adding salts of other metals, metal-atom-containing complex compounds, or alkali salts with anions other than formic acid. However, a disadvantage of this approach is that the flame exhaust may then contain harmful combustion products, or the desired flame coloration with the spectral lines of the metal atoms may be disrupted by light emissions from the combustion products of the anion or complexing agent.

[0032] Examples of implementation

[0033] Note: Dimensions in the drawings are given in millimeters.

[0034] Example 1

[0035] This embodiment is a simple spirit lamp without automatic fuel supply control. It is shown in Figures 1.1 to 1.15.

[0036] Figure 1.1 shows a top view of the simple spirit lamp. Figure 1.2 shows the longitudinal section through the section plane labelled X and X' in Figure 1.1, and Figure 1.3 shows the longitudinal section through the section plane labelled Y and Y' in Figure 1.1.

[0037] The simple spirit lamp according to this embodiment consists of a cylindrical tin can, on the top of which is the torch head that produces the flame. It is composed of five components: the tank 1, the combustion cup 2, the riser pipe 4, the sealing ring 5, and the flow restrictor 10.

[0038] Tank 1 is shown in Figures 1.4, 1.5, and 1.6. Figure 1.4 shows the side view of the upright tank 1, Figure 1.5 the top view, and Figure 1.6 the longitudinal section along the section plane marked X and X' in Figure 1.5. Tank 1 has a central, round filling opening 1.2 on its upper end face 1.1. The level limiter 1.3 is attached to the filling opening 1.2. This is a simple pipe fitting that extends from the upper end face 1.1 into the interior of tank 1. When fuel is filled into the empty tank 1 through the filling opening 1.2 while the tank is upright, the displaced air can initially reach the level limiter 1.3. The fuel level in tank 1 then rises. Once the fill level has reached the lower end of the fill level limiter 1.3, no further air can be displaced from the upper area of ​​tank 1 and the fill level cannot rise further.The level limiter 1.3, which extends to less than half the height of tank 1, ensures that tank 1 can only be filled to a maximum of 31% of its volume. Thus, after filling, the amount of air at the top of tank 1 always has the minimum volume required for the proper functioning of the fuel supply during operation. Furthermore, the level limiter 1.3 prevents fuel from leaking out of the filling opening 1.2, even if tank 1 is tipped over or upside down, as shown in Figures 1.14 (tipped tank 1 with open filling opening 1.2) and 1.15 (upside-down tank 1 with open filling opening 1.2). The level limiter 1.3 also has a small diameter. It is smaller than the minimum diameter required for flame propagation in a tube filled with a mixture of air and gaseous fuel.This prevents the mixture of air and gaseous fuel remaining in tank 1 after it has been emptied from being caused to explode by a flame or other ignition source located at the filling opening 1.2.

[0039] The combustion cup 2 is shown in Figures 1.7 to 1.9. Figure 1.7 shows a top view of this component, Figure 1.8 the longitudinal section through the section plane labeled X and X' in Figure 1.7, and Figure 1.9 the longitudinal section through the section plane labeled Y and Y' in Figure 1.7. The combustion cup 2 is a cylindrical metal body with a base 2.2 and a large contact surface. It is made of aluminum. Heat conductors 2.1 are located at the upper edge of the combustion cup 2. They are long enough to extend into the hot outer zone of the flame, as shown in Figure 1.13. The combustion cup 2 has a round opening 2.6 at its base with a receiving groove 2.7 for the sealing ring 5. The opening 2.6 is located in the assembled simple spirit lamp directly above the filling opening 1.2 of the tank 1.

[0040] The sealing ring 5 is a simple rubber O-ring. When using ethanol or methanol as fuel, a simple rubber material, such as a styrene-butadiene copolymer, is sufficient.

[0041] The riser pipe 4 is shown in Figures 1.10 to 1.12. It is a tube made of aluminum with an inner diameter of 0.4 millimeters. Inside, a cotton thread acts as a flow resistance 10. The flow resistance 10 is designed so that the fuel delivery rate, even at the highest operating pressure, is lower than the evaporation rate resulting from boiling in the combustion chamber 2. This ensures that the combustion chamber 2 does not overflow. The riser pipe 4 also forms the closure of the tank 1. The bracket 4.2 serves as a handle. To close the tank, the riser pipe 4 is simply inserted into the center of the combustion chamber 2. The riser pipe 4 is held in place by the clamping action of the sealing ring 5.

[0042] The combustion cup 2 is glued to the upper end face 1.1 of the tank 1 with a sufficiently heat-resistant adhesive, for example a silicone polymer. The large surface area of ​​the base 2.2 ensures good thermal conductivity between the base and the upper end face 1.1 of the tank 1.

[0043] To operate the simple spirit lamp, it is first filled with fuel. For this, the cap consisting of the riser pipe 4 is first pulled out of the simple spirit lamp and the tank 1 is filled with fuel. A bottle with an attached tube that fits into the level limiter 1.3 is preferably used for filling.

[0044] The riser pipe 4 is then reinserted. Using a lighter, one of the heat conductors 2.1 or the upper edge of the tank 1 is heated, forcing fuel into the combustion chamber 2. The fuel is ignited. During operation, the internal pressure rises, but does not exceed 60 hPa. This pressure is sufficient to pump the fuel. However, it is not sufficient to force the riser pipe 4 out of the sealing ring 5.

[0045] Example 2

[0046] This embodiment is a simple spirit lamp with an automatically regulated fuel supply. The embodiment is illustrated in Figures 2.1 to 2.16. Figure 2.1 shows a top view of the simple spirit lamp. Figure 2.2 shows a longitudinal section through the plane of section identified by X and X' in Figure 2.1, and Figure 2.3 shows a longitudinal section through the plane of section identified by Y and Y' in Figure 2.1.

[0047] The simple spirit lamp according to this embodiment consists of a cylindrical tin can, on the top of which the torch head that produces the flame is located. It is composed of five components: the tank 1, the combustion cup 2, the inner combustion cup 3, the riser pipe 4, and the sealing ring 5.

[0048] Tank 1 is shown in Figures 2.4, 2.5, and 2.6. Figure 2.4 shows the side view of the upright tank 1, Figure 2.5 its top view, and Figure 2.6 a longitudinal section. It has a central, round filling opening 1.2 on its upper end face 1.1. The level limiter 1.3, which extends from the upper end face 1.1 to the center of the tank, is attached to the filling opening 1.2. The level limiter 1.3, which extends to less than half the height of tank 1, ensures that tank 1 can only be filled to a maximum of 47% of its volume. Thus, the amount of air at the top of tank 1 after filling always remains at the minimum volume required for the proper functioning of the fuel supply control system during operation. Furthermore, the level limiter 1.3 also ensures that no fuel leaks out through the filling opening 1.2 if the container is tipped over or upside down, as shown in Figures 2.Figure 15 (overturned tank 1 with open filling opening 1.2) and Figure 2.16 (upside-down tank 1 with open filling opening 1.2).

[0049] The combustion cup 2 is shown in Figures 2.7 to 2.9. Figure 2.7 shows a top view of this component, Figure 2.8 shows a longitudinal section through the section plane identified by X and X' in Figure 2.7, and Figure 2.9 shows a longitudinal section through the section plane identified by Y and Y' in Figure 2.7.

[0050] The combustion cup 2 is a cylindrical metal body with a base 2.2 and a large contact surface. It is made of aluminum. Heat conductors 2.1 are located at the upper edge of the combustion cup 2. They are long enough to extend into the hot outer zone of the flame, as shown in Figure 2.14. The combustion cup 2 has a round opening 2.6 at its base with a receiving groove 2.7 for the sealing ring 5.

[0051] The inner combustion cup 3 is shown in Figures 2.10 to 2.12. Figure 2.10 shows a top view of the inner combustion cup 3. Figure 2.11 shows a longitudinal section through the section plane designated by X and X' in Figure 2.10, and Figure 2.12 shows a longitudinal section through the section plane designated by Y and Y' in Figure 2.10. The inner combustion cup 3 is made of aluminum. It carries the inner heat conductors 3.1 along its upper edge. These are also long enough to extend into the hot outer zone of the flame, as shown in Figure 2.14. The inner combustion cup 3 has a bottom opening 3.3 for receiving the riser pipe 4.

[0052] The riser pipe 4 is shown in longitudinal section in Figure 2.13. It is a small-diameter tube made of aluminum. The inner diameter of the riser pipe 4, and thus its flow resistance, is dimensioned such that at the maximum operating pressure resulting from the described control process, less fuel is always conveyed upwards per unit of time than can be vaporized by boiling in the inner combustion chamber 3 and the combustion chamber 2 combined. The riser pipe 4 has a groove 4.1 at its upper end for fitting into the sealing ring 5. It is secured in the bottom opening 3.3 of the inner combustion chamber 3 by welding or bonding. The assembly of the inner combustion chamber 3 and the riser pipe 4 forms the closure of the tank 1. To close the tank, this assembly is inserted into the center of the combustion chamber 2, where it snaps into the sealing ring 5.

[0053] The combustion cup 2 is bonded to the upper end face 1.1 of the tank 1 with a sufficiently heat-resistant silicone polymer. The large surface area of ​​the base 2.2 ensures good thermal conductivity between the base and the upper end face 1.1 of the tank 1. The opening 2.6 in the base of the combustion cup 2 is located above the filling opening 1.2 of the tank 1. To operate the simple spirit lamp, it is first filled with fuel. For this purpose, the cap, consisting of the inner combustion cup 3 and the riser tube 4, is first pulled out of the tank 1, and the tank 1 is filled with fuel. A bottle with an attached tube that fits into the level limiter 1.3 is preferably used for filling. The inner combustion cup 3 with the riser tube 4 is then reinserted. One of the heat conductors 2 is then ignited with a lighter.1 or the upper edge of the tank 1 is heated, which forces fuel into the inner combustion chamber 3. It is then ignited with the lighter. During operation, the internal pressure rises, but does not exceed 40 hPa above ambient pressure. This pressure is sufficient to pump the fuel. However, it is not sufficient to force the seal, consisting of the inner combustion chamber 3 and the riser pipe 4, back out of the sealing ring 5.

[0054] Example 3

[0055] This embodiment is a simple spirit lamp with an automatically regulated fuel supply. It is shown in longitudinal section in Figure 3.1. It largely corresponds to embodiment 2 and thus consists of the tank 1, the combustion chamber 2, the inner combustion chamber 3, the riser pipe 4, and the sealing ring 5. However, unlike embodiment 2, tank 1 is equipped with an additional safety device. This is the thermal insulation layer 6. This is a thin layer of concrete applied to the outside of tank 1. It is reinforced with a wire mesh. The thermal insulation layer 6 is designed to protect the tank from unwanted heat exposure, such as that which would occur, for example, if the simple spirit lamp were accidentally placed on a radiator.Because concrete is a porous material, if combustion chamber 2 overflows, the overflowing fuel is absorbed by the thermal insulation layer 6 and thus prevented from igniting. The subsequent evaporation of the fuel from the thermal insulation layer 6 cools tank 1, which reduces the internal pressure in tank 1, resulting in insufficient fuel being fed and the flame going out.

[0056] Example 4

[0057] This embodiment is shown in Figures 4.1 to 4.11. It is an example of a simple spirit lamp with a regulated fuel supply. It is equipped with an additional safety device. This is a pressure relief device that activates when the pressure in the tank exceeds a certain threshold or when a large, uncontrolled flame burns on the top of the tank 1 due to a failure of the fuel supply control.

[0058] The simple spirit lamp consists of the tank 1, the combustion cup 2, the inner combustion cup 3, the riser pipe 4, the flow resistance 10, the locking washer 7, the locking rim 8 and the sealing ring 5. The inner combustion cup 3 and the riser pipe 4 form a single component.

[0059] Figure 4.1 shows the assembly of all parts as a cross-sectional view.

[0060] Tank 1 is shown in longitudinal section in Figure 4.2. Tank 1 is a cylindrical sheet metal container with the same external dimensions (height and diameter) as tank 1 from embodiment 2. The level limiter 1.3 is inserted into the upper end face 1.1 of tank 1. The level limiter 1.3 is a pipe fitting that extends from the upper end face 1.1 of tank 1 to just above the bottom of the tank 1. The air outlet hole 1.5 is located slightly below the center of the fitting. When tank 1 is filled with fuel through the filling opening 1.2, the fuel initially flows through the gap at the bottom between the level limiter 1.3 and the bottom of the tank into the free volume of tank 1. The displaced air escapes through the air outlet hole 1.5. Once the fill level reaches the same height as the air outlet hole 1.5, no further air can escape and tank 1 will not fill any further. The inner diameter of the fill level limiter 1.The opening 1.3 is large enough to allow flame propagation if it contains a mixture of air and fuel vapor. If ignition occurs at the filling opening 1.2, the flame will therefore travel down the level limiter 1.3. However, ignition of any potentially explosive gas mixture present in tank 1 is prevented by the fact that both the dimensions of the gap between the lower end of the level limiter 1.3 and the bottom of tank 1, and the diameter of the air outlet hole 1.5, are smaller than the critical gap width relevant for flame propagation in the gas mixture in question.

[0061] The combustion cup 2 is shown in Figures 4.3 and 4.4. Figure 4.3 shows the top view, and Figure 4.4 shows the longitudinal section through the section plane, which is labelled X and X' in Figure 4.3. The combustion cup 2 is made of aluminum. It consists of an inner cylindrical body 2.3, which rests on a wide base 2.2. The heat conductors 2.1 are located at the upper edge of the combustion cup 2. Two protective rims 2.4, encircling the inner cylindrical body 2.3 of the combustion cup 2, are mounted on the base 2.2. A groove 2.5 is located in the bottom surface of the base 2.2, extending from the central opening 2.6 of the base 2.2 to its outer edge.

[0062] The common component, representing the inner combustion chamber 3 and the riser 4, is shown in Figures 4.5 and 4.6. Figure 4.5 shows a top view, and Figure 4.6 shows a longitudinal section through this component. This component is a tube made of aluminum, which carries the inner heat conductors 3.1 at its upper end. During operation of the simple spirit lamp, the upper zone 3.2 of the tube contains the boiling fuel and is thus the actual inner combustion chamber 3. The lower part of the tube serves as the riser 4.

[0063] The flow resistance 10 is shown in longitudinal section in Figure 4.7. The flow resistance 10 is a cylindrical body made of cellulose fibers and manufactured using methods known from papermaking.

[0064] The safety rim 8 is shown in Figures 4.8 and 4.9. Figure 4.8 shows a top view, Figure 4.9 a longitudinal section. The safety rim 8 is an annular component and consists of a fuel-resistant thermoplastic. Polyethylene terephthalate (PET) has proven to be a suitable material for a simple spirit lamp operated with methanol or ethanol according to this embodiment.

[0065] The retaining washer 7 is shown in Figures 4.10 and 4.11. Figure 4.10 shows a top view, Figure 4.11 a longitudinal section. This component is a round sheet metal disc with a large hole in the center. It has a crimped edge to receive the retaining rim 8.

[0066] The combustion cup 2 is glued to the top of the tank 1 with silicone adhesive. The opening 2.6 in the base of the combustion cup 2 and the filling opening 1.2 of the tank are aligned. The sealing ring 5 is inserted into the corresponding recess in the opening 2.6 in the base of the combustion cup 2.

[0067] The pressure relief device, consisting of the retaining washer 7 and the retaining rim 8, is attached to the combustion chamber 2 and the upper edge of the tank 1. The retaining washer 7 is glued to the top of the base 2.2 of the combustion chamber 2. The retaining rim 8 is, in turn, glued into the crimped rim groove of the retaining washer 7. The outer zone of the retaining rim 8 has a slightly smaller diameter than the outer upper edge of the tank 1 and therefore, due to mechanical tension, sits securely on the outer edge of the tank 1.

[0068] The common component forming the inner combustion chamber 3 and the riser pipe 4 also serves as the closure of the tank 1. It is inserted into the opening 2.6 in the base of the combustion chamber 2 and is sufficiently secured by the mechanical tension of the sealing ring 5. The lower section of the component, which serves as the riser pipe 4, extends to the base of the tank 1.

[0069] To ensure that sufficient pressure can build up for regulating the fuel supply, the flow resistance 10 is located in the riser pipe 4.

[0070] To operate the simple spirit lamp, the tank 1 is filled with fuel, and the combined component, consisting of the inner combustion cup 3 and the riser pipe 4, is inserted into the combustion cup 2. Then, one of the heat conductors 2.1 or the upper edge of the tank 1 is heated with a lighter. The heat conducted to the top of the tank 1 causes a pressure increase in the upper section of the tank 1, which is filled with air and gaseous fuel. As a result, fuel is forced through the riser pipe 4 into the upper zone 3.2 of the combined component, which forms the inner combustion cup 3 and the riser pipe 4. It is then ignited with the lighter. The flame, through the heat conductors 2.1, provides further energy to the upper section of the tank 1, and more fuel is forced into the inner combustion cup 3 until it overflows.The fuel that has now flowed into the gap between the inner combustion chamber 3 and combustion chamber 2 cools combustion chamber 2 by absorbing the heat of vaporization from the boiling fuel. This reduces the amount of heat energy transferred to the top of tank 1. The pressure in tank 1 drops slightly, and consequently, the fuel flow rate also decreases. The fuel flow rate thus automatically adjusts to the flame's consumption. The additional protective barriers 2.4 placed on the base of combustion chamber 2 increase the control range by allowing fuel to safely overflow the interior of combustion chamber 2. In this case, the fuel flows into the space between the inner cylindrical body 2.3 of combustion chamber 2 and the inner protective barrier 2.4, or between the inner and outer protective barriers 2.4, resulting in significantly improved cooling of the base 2.2, thus resulting in a further reduction in heat transfer to the top of the tank 1. Furthermore, when the flame is fed from the gap located between the protective walls 2.4, it has a larger diameter. Therefore, the heat conductors 2.1 now extend less far into the hot outer zone of the flame. This also reduces the amount of heat transferred to the surface of the tank 1. To further improve operational safety, the simple spirit lamp with regulated fuel supply, as in this example, is equipped with the aforementioned pressure relief device. It consists of the locking disc 7 and the locking rim 8. These two components form a shallow gap 1.4 above the top of the tank 1. This gap is connected to the upper part of the tank 1, which contains the air necessary for pressure build-up, by the groove 2.5, the gap between the level limiter 1.3 and the riser pipe 4 inserted therein, and the air outlet hole 1.5.If, due to external influences, a rapid and excessive pressure increase occurs in tank 1 and consequently also in the space 1.4, a gap opens between the upper edge of tank 1 and the safety rim 8, which is held tightly in place by only slight mechanical tension, and the excess pressure in the tank is released. The safety rim 8 also serves as a safeguard against the possibility that, during operation of the simple spirit lamp, a higher fuel flow rate occurs than can be controlled by the thermal control device described above. This would happen, for example, if the simple spirit lamp were carelessly overheated. In this case, so much fuel would be drawn upwards that the combustion chamber 2 and the spaces between the combustion chamber 2 and the protective rims 2.4 would fill up, and the burning fuel would spill onto the safety disc 7.The flame, now also burning next to the combustion cup 2, melts the thermoplastic material of which the safety rim 8 is made. This results in an immediate pressure drop in tank 1 and the fuel supply ceases. Ignition of the mixture of air and gaseous fuel present in the upper part of the tank is prevented because a flame cannot propagate through such narrow passages as those provided by the groove 2.5 and the space between the riser pipe 4 and the level limiter 1.3. The activation of the pressure relief device due to an excessively large flame deactivates the simple spirit lamp and renders it unusable.

[0071] Example 5

[0072] This embodiment is shown in Figures 5.1 to 5.6. It is an example of a simple spirit lamp with a regulated fuel supply. This simple spirit lamp also has a pressure relief device that activates when the pressure in the tank exceeds a certain threshold or when a large, uncontrolled flame burns on the top of the tank 1 due to a failure of the fuel supply control.

[0073] Figure 5.1 shows the longitudinal section through the fully assembled simple spirit lamp. It consists of the tank 1, the combustion cup 2, the inner combustion cup 3, the riser pipe 4, the flow restrictor 10, and the safety cap 11 with the foil discs 12 affixed to it. The tank 1, the combustion cup 2, and the sealing ring 5 are identical to those used in embodiment 4.

[0074] The inner combustion chamber 3 is shown in Figures 5.2 (top view) and 5.3 (longitudinal section). It consists of an aluminum tube with the inner heat conductors 3.1 located at its upper edge. Only the upper zone 3.2 is filled with fuel during operation and thus forms the actual inner combustion chamber 3. The area below serves as a support for the riser pipe 4.

[0075] The riser pipe 4 is shown in longitudinal section in Figure 5.4. It is a polypropylene (PP) tube with an inner diameter of one millimeter. Inside the riser pipe 4 is the flow resistance 10, which consists of a cotton thread. The riser pipe 4 is inserted into the tubular body of the inner combustion chamber 3. It is tapered at its upper end 4.5. Because most of the interior space of the upper zone 3.2 of the inner combustion chamber 3, which contains the boiling fuel, is now filled by the tapered section of the riser pipe 4, the volume of fuel contained within it during operation is particularly small. This is a safety measure in case the simple spirit lamp is carelessly shaken or tilted during operation. The amount of burning liquid thrown out or spilled is then very small, and the risk posed by it is correspondingly small.

[0076] This embodiment also has an additional pressure relief device. It consists of the safety cover 11 and nine circular foil discs 12 affixed to it. A top view of the safety cover 11 is shown in Figure 5.5. Figure 5.6 shows the section along the section plane marked X and X' in Figure 5.5. The safety cover 11 is a round sheet metal component with a wide hole in the center and a surrounding crimped edge. Near the edge, nine bumps 11.1, each with a hole 11.2 in the center, are embossed at regular intervals. One of the round foil discs 12 is affixed to each of the bumps 11.1. The material from which commercially available transparent adhesive tapes are made has proven suitable for the foil discs 12, provided the simple spirit lamp is operated with methanol or ethanol. The inner edge of the safety cover 11 is on the foot 2.The combustion cup 2 is glued to the outer edge of the safety cover 11. The crimped groove of the outer edge of the safety cover 11 is glued to the outer edge of the tank 1. In this way, a gap 1.4 is formed between the safety cover 11 and the top of the tank 1. This gap 1.4 is connected to the upper part of the tank 1, which contains the air necessary for pressure build-up, by the groove 2.5, the gap between the level limiter 1.3 and the inner combustion cup 3 inserted therein, and the air outlet hole 1.5. If, due to external influences, a rapid, excessive pressure increase occurs in the tank 1 and thus also in the gap 1.4, one of the foil discs 12 is forced off its boss 11.1 by the pressure acting from below. The hole 11.2 is now open and the overpressure in the tank is released.The foil discs 12 also serve as a safeguard against the possibility that the simple spirit lamp's operation results in a higher fuel flow rate than can be controlled by the thermal control device described above. This would occur, for example, if the simple spirit lamp were carelessly overheated. In this case, so much fuel would be drawn upwards that the combustion chamber 2 and the spaces between the combustion chamber 2 and the protective walls 2.4 would fill up, and the burning fuel would then spill onto the safety cover 11. The flame, now also burning next to the combustion chamber 2, would melt the thermoplastic material from which the foil discs 12 are made. This would cause an immediate pressure drop in the tank 1, and the fuel supply would cease.Ignition of the mixture of air and gaseous fuel present in the upper part of the tank is prevented by the fact that a flame cannot propagate through such narrow passages as those provided by both the groove 2.5 and the space between the inner combustion cup 3 and the level limiter 1.3. The activation of the pressure relief device due to overpressure or an excessively large flame disables the simple spirit lamp. It can be reactivated by gluing new foil discs 12 onto the bumps 11.1 of the safety lid 11.

[0077] Example 6

[0078] This embodiment is shown in Figures 6.1 to 6.10. It is an example of a simple spirit lamp with a regulated fuel supply. It is designed as a disposable item and cannot be refilled once the fuel introduced during manufacturing has been used up.

[0079] Figure 6.1 shows a top view of the fully assembled simple spirit lamp. Figure 6.2 shows a longitudinal section through the fully assembled simple spirit lamp in its transport state.

[0080] Figure 6.3 shows the longitudinal section through the fully assembled simple spirit lamp in operating condition.

[0081] The simple spirit lamp consists of the tank 1, the combustion cup 2, the inner combustion cup 3, the riser pipe 4, the sealing ring 5, and the flow restrictor 10. It is equipped with a level limiter 1.3, whereby the combustion cup 2, the upper end face 1.1 of the tank 1, and the level limiter 1.3 are combined in a single component. Furthermore, the inner combustion cup 3 and the riser pipe 4 also form a single component.

[0082] To facilitate recycling, all components except for the sealing ring 5 are made of aluminum.

[0083] Tank 1 is shown in Figures 6.4 (top view) and 6.5 (section along the plane marked Y and Y' in Figure 6.2). The upper end face 1.1 of tank 1 is not shown here, as it has been integrated into the combination component shown in Figures 6.6 and 6.7. The combination of the combustion cup 2, the upper end face 1.1, and the level limiter 1.3 is shown in Figures 6.6 (top view) and 6.7 (section along the plane marked Y and Y' in Figure 6.6). The combination component is a flat, heart-shaped disc with a raised rim. It is used as the upper end face 1.1 of tank 1 in the assembled simple spirit lamp. The flat, heart-shaped disc transitions into a tube in its center. The upper section 2.8 of this tube forms the actual combustion cup 2 in the assembled simple spirit lamp. The heat conductors 2.1 are located at its upper edge.The lower part of the tube serves as a level limiter 1.3. After the simple spirit lamp has been manufactured, it is sealed by the transport closure 1.6.

[0084] The combined component, consisting of the inner combustion chamber 3 and the riser 4, is shown in Figures 6.8 (top view) and 6.9 (side view). Figure 6.10 (section along the plane marked Y and Y' in Figure 6.8) shows this combined component with the installed flow resistor 10. It is a tube that carries the inner heat conductors 3.1 at its upper end. The zone 3.2 below the inner heat conductors 3.1 forms the actual inner combustion chamber 3. The area below this is used as the riser 4. The flow resistor 10 is a piece of cotton cord. In the fully assembled simple spirit lamp, the flow resistor 10 is located in the riser 4. The upper end of the flow resistor 10 then forms the bottom of the inner combustion chamber 3.

[0085] During manufacturing, the simple spirit lamp is filled to the fill level H shown in Figure 6.2, and the lower end of the combination component, which embodies the riser pipe 4 and the inner combustion cup 3, is inserted into the fill level limiter 1.3 such that the lower end of the riser pipe 4 rests on the transport closure 1.6. The simple spirit lamp is then in the transport state shown in Figure 6.2.

[0086] To use the lamp, the user presses on the inner heat conductors 3.1. This shears off the transport closure 1.6 through the riser pipe 4 and pushes it onto the bottom of the tank 1. The simple spirit lamp is then in the operating state shown in Figure 6.3. The fuel can now flow from the tank 1 into the riser pipe 4. If the transport closure 1.6, sheared off during pressing, should block the lower end of the riser pipe 4, the passage hole 4.3 in the wall of the riser pipe 4 ensures that the fuel can flow into the riser pipe 4 without obstruction.

[0087] After the user has put the simple spirit lamp into operating mode, he heats one of the heat conductors 2.1 or the upper edge of the tank 1 with the lighter, as in the other embodiments, causing fuel to flow into the inner combustion chamber 3 and ignite. Once the fuel supply is exhausted and the tank 1 has cooled down, the simple spirit lamp cannot be refilled because the level limiter 1.3, which extends to the bottom of the tank 1, prevents the air now filling the tank from being displaced.

[0088] Example 7

[0089] The embodiment is shown in Figures 7.1 to 7.10. It is an example of a simple spirit lamp with a glass windscreen 14.

[0090] Figure 7.1 shows the longitudinal section through the fully assembled simple spirit lamp. It consists of the tank 1, the combustion cup 2, the inner combustion cup 3, the riser pipe 4, the sealing ring 5, the flow resistance 10, the windscreen holder 13 and the windscreen 14.

[0091] Tank 1 is shown in longitudinal section in Figure 7.2. Tank 1 is a cylindrical sheet metal container. The level limiter 1.3 is inserted into the upper end face 1.1 of tank 1. The level limiter 1.3 is a pipe fitting that extends from the upper end face 1.1 of tank 1 to just above the bottom of the tank 1. The air outlet hole 1.5 is located slightly below the center of the fitting. When tank 1 is filled with fuel through the filling opening 1.2, the fuel initially flows through the gap at the bottom between the level limiter 1.3 and the bottom of the tank into the free volume of tank 1. The displaced air escapes through the air outlet hole 1.5. Once the fuel level reaches the same height as the air outlet hole 1.5, no further air can escape and tank 1 is no longer filled. The inner diameter of the level limiter 1.The opening 1.3 is large enough to allow flame propagation if it contains a mixture of air and fuel vapor. If ignition occurs at the filling opening 1.2, the flame will therefore travel down the level limiter 1.3. However, ignition of any potentially explosive gas mixture present in tank 1 is prevented because both the dimensions of the gap between the lower end of the level limiter 1.3 and the bottom of tank 1, and the diameter of the air outlet hole 1.5, are smaller than the critical gap width relevant for explosion propagation in the gas mixture in question.

[0092] The combustion cup 2 is shown in longitudinal section in Figure 7.3. It is made of aluminum. It consists of an inner cylindrical body 2.3, which rests on a wide base 2.2. The heat conductors 2.1 are located at the upper edge of the inner cylindrical body 2.3. Two protective rims 2.4, encircling the inner cylindrical body 2.3 of the combustion cup 2, are also mounted on the base 2.2.

[0093] The inner combustion chamber 3 is shown in longitudinal section in Figure 7.4. It consists of an aluminum tube with the inner heat conductors 3.1 located at its upper edge. Only the upper zone 3.2 is filled with fuel during operation and thus forms the actual inner combustion chamber 3. The area below it serves as a support for the riser pipe 4.

[0094] The riser tube 4 is shown in longitudinal section in Figure 7.5. It is a polypropylene (PP) tube with an inner diameter of one millimeter. Inside the riser tube 4 is the flow resistance 10, which consists of a cotton thread. The riser tube 4 is inserted into the lower section of the inner combustion chamber 3, which serves as a support. It is tapered at its upper end 4.5. Because, in the assembled unit, most of the interior space of the upper zone 3.2 containing the boiling fuel is filled by the tapered upper end 4.5 of the riser tube 4, the volume of fuel contained within it during operation is particularly small. This is a safety measure in case the simple spirit lamp is carelessly shaken or tilted during operation. The amount of burning liquid thrown out or spilled is then very small, and the risk posed by it is correspondingly small.

[0095] The windshield bracket 13 is shown in Figures 7.6, 7.7, and 7.8. Figure 7.6 shows the top view, Figure 7.7 the side view, and Figure 7.8 a longitudinal section. The windshield bracket 13 is a flat sheet metal ring whose inner edge is raised to form a collar 13.1. The air inlet holes 13.2 are located in this collar. The windshield bracket 13 is placed onto the tank 1 and secured by means of a crimped edge.

[0096] The windscreen 14 is shown in Figures 7.9 (top view) and 7.10 (side view). It is a tube that tapers upwards and is made of so-called Jena glass. Since the windscreen 14 needs to be cleaned from time to time, it is placed on the windscreen holder 13 without a fixed connection.

Claims

Claims 1 Simple spirit lamp, consisting of a tank 1 and a torch head, which is supplied with fuel from the tank via a riser pipe 4 extending from the bottom of the tank 1, characterized by the fact • the torch head consists of a metallic combustion cup 2, • metal strips, metal wires or sheet-shaped metal bodies serving as heat conductors 2.1 are connected to the combustion cup 2, • the riser pipe 4 ends inside the combustion bowl 2, • the combustion cup 2 sits on the top of the tank 1. 1.1 Simple spirit lamp according to claim 1 , characterized by the fact that • in the filling opening 1.2 of the tank 1, a tubular level limiter 1.3 leading into the interior of the tank 1 is attached in such a way that when filling the tank 1, less than half of the tank volume is filled with fuel. 1.1.1 Simple spirit lamp according to claim 1.1 , characterized by the fact that • the filling opening 1.2 of the tank 1 is located under an opening 2.6 in the bottom of the combustion bowl 2. 1.2 Simple spirit lamp according to claim 1 , characterized by the fact that • a further, smaller, metallic, inner combustion cup 3 is attached inside the combustion cup 2, • metal strips, metal wires or sheet-shaped metal bodies serving as internal heat conductors 3.1 are connected to the inner combustion cup 3, • a connecting or sealing component made of a non-metallic material is located between the inner combustion cup 3 and the combustion cup 2, • the riser pipe 4 ends in the inner combustion cup 3. 1.2.1 Simple spirit lamp according to claim 1.2 , characterized by the fact that • the filling opening 1.2 of the tank 1 is located under an opening 2.6 in the bottom of the combustion cup 2 and the inner combustion cup 3 is simultaneously the closure of the filling opening 1.

2. 1.2.1.1 Simple spirit lamp according to claim 1.2.1 characterized in that a tubular level limiter 1.3 leading into the interior of the tank 1 is attached in the filling opening 1.2 of the tank 1 in such a way that less than half of the tank volume is filled with fuel when the tank 1 is filled. 1.2.1.1.1 Simple spirit lamp according to claim 1.2.1.1 , characterized by the fact that • a transport closure 1.6 is located in the level limiter 1.

3. 1.2.1.1.1.1 Simple spirit lamp according to claim 1.2.1.1.1 , characterized by the fact that • the transport closure 1.6 consists of a metallic membrane which was produced by primary forming together with the level limiter 1.

3. 1.2.2 Simple spirit lamp according to claim 1.2 , characterized by the fact that • the construction has at least one pressure relief device, the pressurized side of which is connected to the interior of tank 1 by a gas-carrying line or a gas-carrying passage. 1.2.2.1 Simple spirit lamp according to claim 1.2.2 , characterized by the fact that • The pressure relief device includes at least one component that is destroyed as a result of the action of a flame burning next to the flare head and whose destruction triggers the desired pressure relief of the interior of tank 1. 1.2.2.1.1 Simple spirit lamp according to claim 1.2.2.1 , characterized by • that the pressure relief device consists of an additional cover extending from the combustion cup to the upper edge of the tank, composed of a metal locking disc 7 and a raised locking rim 8 made of a combustible polymer material. 1.2.2.1.2 Simple spirit lamp according to claim 1.2.2.1 , characterized by • that the pressure relief device consists of an additional safety cover 11 extending from the combustion cup to the upper edge of the tank, which has holes sealed with foil discs 12. 1.3 Simple spirit lamp according to claim 1 , characterized by • that the tank has a heat insulation layer 6 made of a porous, non-combustible material. 1.3.1 Simple spirit lamp according to claim 1.3 , characterized by • that the thermal insulation layer 6 consists of concrete reinforced with a wire mesh.

2. Use of solutions of one or more metal salts or metal atom-containing complex compounds in methanol and ethanol or mixtures of the two alkanols in any proportions as fuel for the patented simple spirit lamp, wherein up to 30% water may also be contained in the said mixture. 2 1 Use of solutions according to claim 2 , characterized in that the metal salts dissolved in the fuel are one or more alkali formates, alkali acetates or mixtures of alkali formates and alkali acetates. 2 1 1 Use of solutions according to claim 2.1 , characterized in that sufficient formic acid or acetic acid is added to the solution to minimize the corrosion effect on the material of the tank 1 caused by the basic reaction of the alkali formates or alkali acetates.

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