Patent Publication Number: US-4839780-A

Title: Simulative candle

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a decorative lamp, and more particularly to a lamp using a battery. 
     Nowadays, there are two types, of power supply for Christmas decorative lamps i.e. a.c. and d.c. These, however, have the following disadvantages. 
     (1) The a.c. powered lamp is limited by the length of the electric wire and requires a power-supplying socket. Such a decorative lamp can not be put at any place at one&#39;s option. In addition, since the a.c. power is normally relatively high, a dangerous situation may result when there is an internal short circuit. Thus, it is inconvenient and may be dangerous. 
     (2) The d.c. powered lamp is battery-powered and uses tungsten wire. It is thus power-consuming and has a shortened life. In addition, since it is battery-powered, its light is monotonous and not dynamically decorative. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a simulative candle capable of being conveniently used and having a dynamically decorative effect. 
     It is further an object of the present invention to provide a simulative candle having a lengthened life and being lower in power consumption. 
     According to the present invention, a simulative candle includes a housing receiving therein a battery, an oscillator converting the battery power into an a.c. power, a half-wave-rectifying filtering d.c. electric power, and a neon lamp energized by the astatic d.c. power to sparkle like a real candle flame. 
     The present invention may best be understood through the following description with reference to the accompanying drawings, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a block diagram showing a simulative candle according to the present invention; 
     FIG. 2 is a circuit diagram showing a simulative candle in FIG. 1; 
     FIG. 3 is a perspective view showing a preferred embodiment of a simulative candle according to the present invention; and 
     FIG. 4 is a side view of FIG. 3 according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIGS. 1-4, the present simulative candle includes a housing (4, 42) for receiving therein a battery 11 providing a d.c. power, a converter 2 which first converts the battery power into an astatic high-voltage but small-current electric power (having a ripple frequency), and a neon lamp 3 energized by the astatic power and having two electrode piece 31, 32. The sparkling characteristic of lamp 3 can be varied and determined by adjusting an oscillating frequency and the astatic power in converter 2 and/or suitably shaping electrode piece 31, 32 in order to simulate a candle flame and/or to be dynamically decorative. 
     Converter 2 includes an oscillator constituted by a transistor 21 and an inductance coil 22 for converting the battery power into high-voltage but small-current a.c. power having a fixed frequency, and a half-wave-rectifying filtering network formed by a rectifying diode 27 and a filtering capacitor 26 for changing the a.c. power into an astatic d.c. power with a ripple which energizes lamp 3. Since the frequency can be adjusted by varying the inductance of coil 22, the lamp 3 can be stimulated to sparkle like a real candle flame. Since the working principle of these electric elements is well known in the art, any further detail therefor will not be given here. 
     As shown in FIG. 2, the coil 22 has opposite ends connected between the emitter and collector of transistor 21. A parallel RC circuit is connected between the base of transistor 21 and one of the opposite ends of coil 22. Battery 11 is connected between a tap of coil 22 and the one end of the coil 22 which is connected to the RC circuit. A further capacitor is connected in parallel to battery 11. The diode 27 of the filtering network is connected between the one end of the coil 22 and one electrode of lamp 3. The opposite electrode of lamp 3 is connected to the opposite end of coil 22. Capacitor 26 of the filtering network is connected between the electrodes of the lamp. 
     The housing can include a candle holder 4 having a handle 41 and a switch 43 for controlling whether battery 11 is providing its d.c. power for converter 2. A candle body portion 42 is mounted on candle holder 4 and carries thereon the neon lamp 3 having, electrode pieces which dynamically sparkle like a real candle flame. 
     Through the above description, it should now become readily apparent how and why the present invention can achieve the objects it contemplates.