Candle

Abstract

 A candle with a candle body and a wick arranged within the candle body. The solution of the invention is specified by the features of claim 1 comprises a switch that switches in response to the wick being lit or extinguished. Coupling the switching to the wick (and thus the candle) being lit or extinguished allows for an easy an reliable control of the additional functions by the switch. The additional functions may comprise controlling the electric lighting of a room by a wireless connection.

Description

Technical Field

[0001] The invention relates to a candle with a candle body and a wick arranged within the candle body.

Background Art

[0002] Candle usage has been developed gradually from mere illumination to lighting for special occasions, e. g. to create a cosy atmosphere, to celebrate special occasions (birthdays, Christmas etc). Different kinds of candles for entertainment are known, providing additional functions, such as flickering candles, music candles etc.

[0003] Current embodiments of flickering candles or music candles are rather cumbersome to control, i. e. to switch them on and off. Often, the switching of the additional features is not reliable, i. e. unintentional switching on or off happens. Furthermore, their construction is rather complex and thus expensive. Their use therefore is limited to special occasions.

Summary of the invention

[0004] It is the object of the invention to create a candle pertaining to the technical field initially mentioned, that provides easy and reliable control of the additional functions and has a simple construction.

[0005] The solution of the invention is specified by the features of claim 1. According to the invention the candle comprises a switch that switches in response to the wick being lit or extinguished.

[0006] Coupling the switching to the wick (and thus the candle) being lit or extinguished allows for an easy and reliable control of the additional functions by the switch.

[0007] Preferentially, the candle comprises an integrated circuit (IC) controlling electric or electronic equipment depending on the wick being lit or extinguished. Switching by ICs is very reliable and according components are compact and cheap. They allow for switching a large variety of different loads.

[0008] Preferably, the electronic equipment is arranged inside the candle. This allows for providing an all-in-one unit which is not distinguishable from a usual candle as long as the additional functions are not activated (by lighting the candle). Therefore, surprise effects are possible. Furthermore, the electronic equipment is protected by the candle body, usually made of beeswax, paraffin etc.

[0009] Advantageously, the electronic equipment comprises a power source, in particular a battery, a rechargeable battery or a capacitor fed by a photo diode. The power source provides electricity for performing the additional functions by the electronic equipment. Depending on the load, a usual battery may suffice. For higher loads or if a long-time use is desired, a rechargeable battery is preferred. It may be recharged from the outside by conventional cables or by induction. Alternatively, it may be recharged by solar cells, photo diodes or other means for generating electric energy comprised by the candle. For loads needing much less electric energy, such as small ICs and liquid crystal displays, a capacitor charged by one or a plurality of photo diodes (making use of the candle light or sunlight) may suffice. Such a power source is likewise suitable for loads that need rather high currents during a very short time such as flashing LEDs or flashlights.

[0010] In one preferable implementation of the invention the electronic equipment comprises at least one LED glowing through the candle body, but preferentially a plurality of LEDs, having in particular different colours. The LEDs may be subsequently or collectively lit and thus create a delightful play of colours and thus an eye-catcher for guests. The effect may be even improved if the LEDs are controlled such as to flicker, in particular by an according IC controlling the current and/or voltage delivered to the LEDs. By gradually reducing the power of a first LED and at the same time gradually increasing the power of a second LED, colour transitions may be realised.

[0011] In another implementation of the invention the electronic equipment comprises a means for generating sound, in particular for playing a melody. Such means may comprise an IC generating a sound signal fed to a small loudspeaker, complex sounds may be generated by a digital signal processor (DSP). Candles playing a melody are suitable for celebrations such as birthdays, Christmas etc. The functions of lighting (by included LEDs) and playing music may be integrated into the same candle.

[0012] In yet another implementation of the invention, the electronic equipment comprises a means for wireless control of external equipment, in particular an electric lighting of a room, preferentially by infra-red or radio signals. Systems for wireless control of the electric lighting of a room are known and installed in a large number of modern flats. Using wireless control, the complexity of the electrical wiring may be greatly reduced. Furthermore, the lighting may be switched by portable remote controllers. Infra-red or radio signals (e. g. according to the bluetooth standard) may be used to transmit the information from the control device to the receiver connected to or comprising a switch controlling the corresponding light sources. Often, not only switching on or off but also dimming the light is possible. A candle including a means for wireless control of electric lighting simplifies the process of lighting the candle and at the same time dimming (or switching off) the ambient light to create a cosy or romantic atmosphere. The means may be formed such that they are compatible with commercially available systems for wirelessly control of the lighting. Alternatively, they may include corresponding receivers that may be installed between a power source and the light source to be controlled.

[0013] Not only light sources but as well other electric or electronic devices such as hi-fi equipment or an electric fireplace may be controlled by the inventive candle. Finally, the candle may submit information about it being lit or extinguished to fire prevention equipment. This may be very important in rooms comprising a lot of inflammable materials such as wood or textiles and where a lot of candles are used to provide for characteristic illumination, e. g in museums or restaurants.

[0014] Alternatively, external devices are switched by means of a cable plugged in an according socket arranged at the electronic equipment.

[0015] Preferably, the switch and all other electronic equipment is enclosed in the candle body such that it is not visible from the outside. This allows for surprise effects and protects the electronic equipment.

[0016] Preferably, the electric and/or electronic elements are modularly arranged within the candle. This allows for replacing the elements (e.g. containing a battery) once they have reached the end of their lifetime. Similarly, the same modular elements may be used for a plurality of candles, if the lifetime of the candle is shorter than the lifetime of the electronic or electric elements. Thereby, the environment is protected from unnecessary waste and money may be saved.

[0017] In one implementation of the invention the switch is mounted on a base arranged near a base portion of the candle, in particular on a printed circuit board (PCB). The base region of the candle is furthest from the flame and thereby does not experience high temperatures. A thermal insulation of the switch (and other electronic elements arranged close to the switch) therefore is not necessary. The rest of the candle body burns down during the lifetime of the candle. Therefore, a switch arranged in the base portion does not limit the lifetime of the candle. Furthermore, nicely shaped candles are often tapered in direction of their top portion and therefore the base portion features more space.

[0018] Alternatively, the switch is arranged on a dish-like metal foil disposed close to the upper end of the candle, whereby the metal foil is in particular made of bright aluminium. The size of the dish-like metal foil is slightly smaller than that of the candle body's cross-section. There is a small hole in the middle of the metal foil such that the wick may pierce the foil arranged within the candle body. The foil is shaped such that it is slightly depressed in its centre and the material is chosen such that the upper side of the foil reflects a large fraction of the heat coming from the flame. Because of the foil the candle body does not melt directly because of the flame but through the heated metal foil. Therefore, the speed of melting is even and the candle body will not have a melted gap. Furthermore, the metal foil avoids overflowing of the liquid wax and therefore inhibit wax spillage. The switch arranged on the metal foil has a generally constant distance from the flame and therefore from the light and heat source. This provides for a reliable switching depending on the status of the candle. A small insulated electrical cable may be comprised in the candle, leading from the switch to other electric and/or electronic elements arranged near the base portion of the candle.

[0019] In another implementation of the invention the switch has an oblong form and is arranged parallel and close to the wick. Thereby, always the top portion of the switch is close to the flame. Preferably, the switch may perform its switching function along its entire length and the materials of the switch are chosen such that they burn or melt at the same rate as the wick, such that at most a small portion of the oblong switch pierces the top side of the candle.

[0020] Preferably, the switch comprises two electrodes separated by a fusible insulating material. As soon as the insulating material melts due to the flame of the candle the two electrodes contact each other and an electric circuit is closed. Advantageously, the material of the electrodes is chosen such that it melts later than the insulating material such that as long as the candle is lit the top portion of the switch comprises the two electrodes contacting each other without an insulation in between.

[0021] Preferentially, the two electrodes are constituted by two tightly twisted metal wires of which at least one is insulated by a fusible material, in particular enamel-insulated, whereby the two twisted wires are arranged alongside the wick. The twisted arrangement leads to forces compressing the two wires together and therefore leads to their reliable contact.

[0022] Alternatively, the switch comprises two linear aluminium foils separated by a layer of fusible insulating material, whereby the aluminium foils are arranged parallel to the wick. As soon as the insulating material melts, the aluminium foils get into contact and close an electric circuit. The top portions of the aluminium foils melt later than the insulating material and disappear completely such that the aesthetic impression of the candle is not affected.

[0023] Another implementation of the invention comprises a light sensor, in particular a photo-diode. The sensor is directed towards the flame of the candle and thereby detects if the candle is lit or extinguished. A photo-diode is reliable, easy to install and cheap.

[0024] Preferably, the candle comprises an optical fibre arranged alongside the wick and connected to the light sensor. The fibre conducts light of the flame directly to the light sensor and thereby reduces sensitivity to other sources of light such as daylight or ambient light. Advantageously, the sensor comprises a unique hub for the optical fibre, reserved on a light-shield shielding against all other light sources.

[0025] Preferentially, a difference of light absorbance between liquid and solid wax is detected by the light sensor. To achieve this, the light sensor or an optical fibre conducting light to the light sensor are arranged such that outside light, in particular light from the flame, passes the top portion of the candle before reaching the sensor or the entry of the optical fibre. As long as the candle is lit, the wax (or paraffin etc.) will be liquid and generally have a smaller absorbance for visible light. Soon after the candle is extinguished the wax will solidify and its absorbance will increase. By choosing a suitable (especially dark) wax the change in absorbance of visible light may correspond to orders of magnitude. If an optical fibre is used to conduct the light to the sensor its material is preferably chosen such that it melts as soon as the liquid portion of the wax reaches the material. This ensures that there will always be a layer of wax between the flame and the top end of the fibre.

[0026] In yet another implementation of the invention the candle comprises a thermal sensor, in particular a thermal resistor. Thereby, changes in temperature occurring near the flame are detected and used to trigger the switch.

[0027] Preferably, the candle comprises a heat-insulated heat conductor arranged along the wick and connected to the thermal sensor. This ensures that the heat generated by the flame is conducted to the actual thermal sensor. At the same time, melting of wax in regions far from the flame is prohibited due to the heat insulation.

[0028] Alternatively, the switch comprises a band of a thermally resistive material arranged along the wick. Thereby, always a sensitive portion of the thermally resistive material is arranged close to the flame and shows a difference in resistance, generally a decrease. A corresponding IC detects the decrease of resistance when the candle is lit and accordingly triggers the switch. As soon as the candle is extinguished the resistance starts to increase and the IC triggers the switch in its other state.

[0029] Other advantageous embodiments and combinations of features come out from the detailed description below and the totality of the claims.

Brief description of the drawings

[0030] The drawings used to explain the embodiments show:

Fig. 1

A cross-section of a candle according to the invention;

Fig. 2

the base portion of the candle;

Fig. 3

a cross-section of another embodiment of the invention;

Fig. 4

the aluminium-foil wick of the embodiment;

Fig. 5

the electrical circuit of the candle;

Fig. 6

a cross-sectional view of yet another embodiment of the invention;

Fig. 7

the dish-like metal foil of the embodiment;

Fig. 8

a cross-section of another embodiment of the invention;

Fig. 9

yet another embodiment in cross-section;

Fig. 10

a typical picture of the resistance depending on time.

[0031] In the figures, the same components are given the same reference symbols.

Preferred embodiments

[0032] Figure 1 shows a cross-section of the candle according to the invention. Figure 2 shows a base portion of the candle. The candle is made up of the candle body 103 and the wick 101. At the bottom of the candle body 103 a printed circuit board (PCB) 105 is arranged. The electronic component 104 and two metal switch electrodes 106 are fixed on the PCB 105.

[0033] At one side of the wick 101, two tightly twisted metal enamel-insulated wires 102, forming a double-twisting metal enamel-insulated wire 102 are arranged, running parallel to the wick 101. At its bottom, the two wires 102 are separated and connected to the two metal switch electrodes 106. The switch electrodes are connected to the electronic element 104 arranged on the PCB 105. The electronic element 104 switches additional functions such as flickering light sources or sound-generating devices arranged within the candle or external devices by means of wireless connection or a socket arranged on PCB 105.

[0034] The function of the candle is as follows: As soon as the wick 101 is lit the candle flames up. At this instant the lacquered leather of the double-twisting metal enamel-insulted wire 102 will melt due to the heat generated by the flame. Thus, the two wires are joint and realise the switch function by closing an electric circuit.

[0035] Figure 3 shows a cross-section of another embodiment of the invention. The candle is made up of the candle body 203 and the chassis 207, where the candle body 203 is set on the chassis 207. A cotton-wick 201 and an aluminium-foil wick 202 are arranged interior of the candle body 203, paralleling the axis of candle body 203.

[0036] Several LEDs 204 are set on the chassis 207, encircling the cotton-wick 201. Each LED 204 is connected to an integrated circuit 205 which is also set on the chassis 207. The integrated circuit 205 is as well connected to a button battery 206 serving as a power supply.

[0037] The function of the circuit switch is realised by aluminium foils 208. As can be seen from Figure 4, the aluminium-foil wick 202 is made up of two linear aluminium foils 208 and an isolating material 209 which is located between the aluminium foils 208. The isolating material 209 easily melts when the candle is burning and therefore, the two aluminium-foils 208 are electrically connected at their upper end. The other ends of the aluminium foils 208 are connected to the button battery 206 and the integrated circuit 210 and therefore work as a switch.

[0038] Figure 5 illustrates the electrical circuit of the candle. The integrated circuit 210 controls the lighting of three LEDs 204, namely their lighting times and sequence. By lighting and putting out the different LEDs 204 at different times, a flickering effect is effected. The colours of the three LEDs 204 may be the same or different. The integrated circuit 210 as well as the LEDs 204 are power supplied by button battery 206. The aluminium-foil wick 202 arranged between the button battery 206 and the integrated circuit 205 acts as a switch.

[0039] The aluminium-foil wick 202 will burn together with the cotton-wick 201. Thereby the insulating material 209 which is arranged in between the aluminium foils 208 begins to melt and the aluminium foils 208 are joint and close the electric circuit. The LEDs 204 are lit and flicker sequentially according to the controlling of the integrated circuit 205.

[0040] Figure 6 is a cross-sectional view of yet another embodiment of the invention. The candle is made up of the candle body 301 and the wick 302 which is located in the centre of the cross-section of the candle body 301. A dish-like metal foil 303 is arranged within the candle body 301 near its upper end. As illustrated in Figure 7 a hole 304 is arranged in the centre of the aluminium foil 303. The outer diameter of the foil 303 is slightly shorter than that of the candle body 301 while the diameter of the hole 304 is larger than that of the wick 302 such that the wick 302 gets through the central hole 304 of the aluminium foil 303. The foil 303 is made from bright aluminium, thus providing for reflection of a large fraction of incident heat.

[0041] At the bottom side of the dish-like metal foil 303 a thermal sensor 305 is arranged, protected by a heat-resistant housing. It comprises a thermal resistor that changes its resistance depending on the temperature of the metal-foil 303. This resistance is presented to an integrated circuit 306 mounted on a printed circuit board (PCB) 307 by means of a cable 308 that leads from the thermal sensor 305 to the integrated circuit 306. The cable 308 comprises two wires insulated from each other that are connected to two electrodes connected to the integrated circuit 306. At their upper end, the wires are connected to the two sides of the thermal resistor. The cable 308 is lead in a channel 309 piercing the candle body 301.

[0042] The function is as follows: When the candle is used the flame of the wick 302 cannot heat the candle body 301 directly because of the aluminium foil 303. Therefore, the usual gap on the upper surface of the candle, close to the wick 302 will not arise, i. e. the flame heats the foil and the heated aluminium foil evenly heats the candle body and leads to melting of the wax. Spilling therefore is prohibited. The bright upper side of the metal foil has a reflection effect and reflects light to the ceiling thereby improving the total illumination. The upper side of the foil may be printed with characters and designs thereby realising artistical or advertisement effects. The candle provided by the metal foil alone, independent from the switching function, shows advantages compared to usual candles in that spilling is avoided and the burning down of the candle is even and controlled.

[0043] As soon as the foil shows a higher temperature due to the heat generated by the flame the resistance of the thermal resistor will drop. This is detected by the integrated circuit 306 which is fed by a button battery 310. The integrated circuit 306 controls the function of LEDs 311 arranged within the candle body 301.

[0044] Note that the PCB 307 and all electronic elements are arranged completely within the candle. Therefore, from the outside of the candle it's almost undetectable that it offers additional functions. A surprise effect is guaranteed.

[0045] Figure 8 shows the cross-section of yet another embodiment of the invention. The candle is made up of candle body 401 and the wick 402. There is a printed circuit board (PCB) 407 mounted near the bottom of the candle body 401. An electronic component 403 and a sensor component 405 comprising a photo diode are fixed on the PCB 407. A light shield 404 covers the sensor component 405 except for a round run-through hole in its upper side. An optical fibre 406 is arranged parallel and close to the candlewick 402. One end of the optical fibre 406 extends into the upper round hole of the light-shield 404 and is tightly connected to the sensor component 405. The other end of the optical fibre 406 runs up to the upper surface of the candle and directly receives light of the flame. Therefore, the optical fibre 406 can transmit candle light to the sensor component 405.

[0046] The electronic component 403 is directly linked to the sensor component 405 on the PCB 407. It is fed by a button battery 408 and comprises a signal generator connected to an infra-red transmitter 409 arranged at the outside and close to the bottom of the candle body 401. The infra-red transmitter 408 is directed at an infra-red receiver of an external unit controlling the ambient light.

[0047] The function of the displayed embodiment is as follows. As soon as the candle is lit, the sensor component 405 detects the light of the flame transmitted by the optical fibre 406. The signal generator is triggered to generate a signal corresponding to dim down the ambient light. This signal is transmitted by the infra-red transmitter 408 to the infra-red receiver of the external unit. This unit controls the ambient light such that the illumination is dimmed down. This leads to a cosy atmosphere dominated by the candlelight.

[0048] As soon as the candle is extinguished, the sensor component 405 detects the absence of the flame and triggers the signal generator to generate a signal to restore the prior ambient light. This signal is again transmitted to the external unit via infra-red signals. The unit controls the ambient light in order to restore the prior (full) ambient light - such that after blowing out the candle the room is again illuminated.

[0049] Figure 9 shows yet another embodiment of the invention in cross-section. The candle comprises a candle body 503 and a wick 501. Parallel and close to the wick 501 a thermal sensor 502 is arranged. The thermal sensor comprises two wires 506, 507 connected by a band 508 of a thermally resistive material arranged in between the wires 506, 507. The two wires 506, 507 are connected to two electrodes arranged on a printed circuit board (PCB) 505. An integrated circuit 508 is as well fixed to the PCB 505. It comprises a switch controlled by the resistance between the wires 506, 507 as well as a sound generator which is connected to a compact loudspeaker 504 arranged on the PCB 505.

[0050] The function is as follows: Depending on the candle being lit or extinguished the temperature of the uppermost portion of the band 508 is different. Higher temperatures generally lead to a lower resistance of the band 508. This is detected by the integrated circuit 509 which in turn triggers the sound generator to play a melody if the candle is lit.

[0051] The PCB 505 as well as the integrated circuit 509, the loudspeaker 504 and other elements such as a battery are arranged in a modular housing 511. The modular housing is situated in a suitable intake 510 at the bottom of the candle body 503. Once the candle is burned down, the housing 511 containing all electronics may be reused in another candle having a similar intake 510 and provided by new wires 506, 507 and band 508. For that purpose the housing features a plug at its upper side taking in the lower end portions of the two wires 506, 507. The plug is connected to the two electrodes on the PCB 505.

[0052] Figure 10 shows a typical picture of the resistance R depending on time t. At point 512 the candle is lit. This leads to a significant drop of the resistance of the band 508 which continues until the upper end of the band 508 has reached its final temperature (depending on the material of the band, the heat of the flame as well as the distance of the band to the flame). Now, the resistance slowly increases due to the shortening of the band 507 due to the melting away of the uppermost portion of the band 508. As soon as the candle is extinguished at point 513 the resistance rapidly increases due to the falling temperature of the uppermost portion of the band. The integrated circuit 509 detects the significant drop as well as the rapid rise and thereby lighting or extinction of the candle.

[0053] It is to be understood that single components of the embodiments described, such as the sensor, the switch, integrated circuits, the power supply or means for improving the burning down of the candle may be substituted by the respective component of another embodiment described.

[0054] In summary, it is to be noted that the invention creates a candle that provides easy and reliable control of additional functions and has a simple construction.

Claims

1. Candle with a candle body and a wick arranged within the candle body, the candle comprising a switch that switches in response to the wick being lit or extinguished.

2. Candle according to claim 1, comprising an integrated circuit controlling electric or electronic equipment depending on the wick being lit or extinguished.

3. Candle according to claim 2, characterised in that the electronic equipment is arranged inside the candle.

4. Candle according to claim 3, characterised in that the electronic equipment comprises a power source, in particular a battery, a rechargeable battery or a capacitor fed by a photo diode.

5. Candle according to claim 3 or 4, characterised in that the electronic equipment comprises at least one LED glowing through the candle body, preferentially a plurality of LEDs, having in particular different colours.

6. Candle according to one of claims 3 to 5, characterised in that the electronic equipment comprises a means for generating sound, in particular for playing a melody.

7. Candle according to one of claims 2 to 6, characterised in that the electronic equipment comprises a means for wireless control of external equipment, in particular an electric lighting of a room, preferentially by infra-red or radio signals.

8. Candle according to one of claims 1 to 7, characterised in that the switch and all other electronic equipment are enclosed in the candle body such that it is not visible from the outside.

9. Candle according to one of claims 1 to 8, characterised in that electric and/or electronic elements are modularly arranged within the candle.

10. Candle according to one of claims 1 to 9, characterised in that the switch is mounted on a base arranged near a base portion of the candle, in particular mounted on a printed circuit board (PCB).

11. Candle according to one of claims 1 to 9, characterised in that the switch is arranged on a dish-like metal foil disposed close to the upper end of the candle, whereby the metal foil is in particular made of bright aluminium.

12. Candle according to one of claims 1 to 9, characterised in that the switch has an oblong form and is arranged parallel and close to the wick.

13. Candle according to one of claims 1 to 9 or 12, characterised in that the switch comprises two electrodes separated by a fusible insulating material.

14. Candle according to claim 13 characterised in that the two electrodes are constituted by two tightly twisted metal wires of which at least one is insulated by a fusible material, in particular enamel-insulated, whereby the two twisted wires are arranged alongside the wick.

15. Candle according to claim 13 characterised in that the switch comprises two linear aluminium foils separated by a layer of fusible insulating material, whereby the aluminium foils are arranged parallel to the wick.

16. Candle according to one of claims 1 to 15 characterised in that the switch comprises a light sensor, in particular a photo-diode.

17. Candle according to claim 16 comprising an optical fibre arranged alongside the wick and connected to the light sensor.

18. Candle according to claim 16 or 17 characterised in that a difference of light absorbance between liquid and solid wax is detected by the light sensor.

19. Candle according to one of claims 1 to 17, characterised in that the switch comprises a thermal sensor, in particular a thermal resistor.

20. Candle according to claim 18 comprising a heat-insulated heat conductor arranged along the wick and connected to the thermal sensor.

21. Candle according to claim 18, characterised in that the switch comprises a band of a thermally resistive material arranged along the wick.

Drawing