Abstract:
The present invention is to provide a rapidly rechargeable warning device, which includes a power receiving element for receiving external electric power, a charging control module for receiving electric power from the power receiving element, a fast energy storage element (e.g., a supercapacitor or any rapidly rechargeable components) being rapidly charged by the charging control module and then outputting electricity stored therein, an warning element (e.g., a light-emitting diode, a buzzer, or a vibrator) capable of issuing a warning signal (e.g., a light signal, a warning sound, or vibrations) upon receiving the electricity outputted by the fast energy storage element. Thus, since the fast energy storage element can be fully charged within a short time through being connected to a cigarette lighter socket of a car, or a transformer connected to an indoor power source, the warning device can be used immediately and effectively prevent user from using one-time batteries.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a warning device, more particularly to a rapidly rechargeable warning device, which includes a fast energy storage element (e.g., a supercapacitor or any rapidly rechargeable components) capable of being rapidly charged by a charging control module and then outputting electricity stored therein to a warning element (e.g., a light-emitting diode, a buzzer, or a vibrator) for generating a warning signal (e.g., a light signal, a warning sound, or vibrations). Since the fast energy storage element can be fully charged within a short time through being connected to a cigarette lighter socket of a car, or a transformer connected to an indoor power outlet, the warning device can be used immediately and effectively prevent user from using one-time batteries (which may be unavailable at the moment when needed and will cause environmental pollution inevitably after used). 
     BACKGROUND OF THE INVENTION 
     It is common practice to place eye-catching warning devices around a construction site or around a car broken down on the road as an effective alert to drivers and pedestrians passing by. In addition to bright orange traffic cones, some common examples of such warning devices are warning triangles, reflective plates, and reflective safety vests. Take warning triangles for instance. Commercially available warning triangles are provided with reflective plates for reflecting light projected from an approaching car. At night or dusk, however, the conventional warning triangles, which cannot emit light on their own, become less conspicuous and hence less effective in preventing accidents from happening. 
     As an improvement over the aforesaid prior art, warning devices capable of making sound or emitting light were developed. According to research and observation by the inventor of the present invention, these improved warning devices—be they warning triangles, traffic batons, or warning lights—are mostly powered by one-time batteries, though in some cases rechargeable batteries are used instead as the power source of light-emitting diodes or buzzers in the warning devices. 
     It is understood that the (stored) energy of a one-time battery or a rechargeable battery (hereinafter referred to collectively as a battery) will, by nature, be gradually released and lost. Therefore, a spare battery which has never been used will eventually lose at least some of its energy. If the batteries of a warning device happen to be dead or have insufficient electricity in case of an emergency, new batteries must be purchased, which not only costs extra money but also, when one-time batteries are used in large quantities, leads to a waste of resources and pollution, not to mention the untimeliness of the purchase, considering only the urgency of the situation. Moreover, it is practically impossible to buy new batteries if the emergency takes place in a mountainous area or a remote suburb or on the highway. Should attempts be made to charge the batteries of the warning device, the charging process is so time-consuming that the warning device may still be short of electricity and incapable of providing warning when needed; consequently, accidents may follow. 
     The issue to be addressed by the present invention is to solve the various problems of the conventional warning devices and provide a warning device with a fast energy storage element which can be fully charged within a short time. Thus, pollution as well as a waste of resources which may otherwise result from excessive use of one-time batteries can be prevented, and warning devices can be used in a more timely and convenient manner than the prior art counterparts. 
     BRIEF SUMMARY OF THE INVENTION 
     In light of the various problems of the conventional warning devices during use, the inventor of the present invention conducted extensive research and finally succeeded in developing a rapidly rechargeable warning device in which a fast energy storage element can be fully charged within a short time. Thus, the timeliness and convenience in utilizing the warning device are effectively enhanced, and excessive use of one-time batteries is avoided to the advantage of environmental protection. 
     It is an object of the present invention to provide a rapidly rechargeable warning device (e.g., a warning triangle, a traffic baton, a warning light, a warning sign, or a light-emitting safety vest) which includes a housing, a power receiving element, a charging control module, a fast energy storage element, and a warning element. The power receiving element is provided on the housing and is configured for connecting with a power cord or a transformer so as to connect to an external power source (e.g., the cigarette lighter socket of a car or an indoor power outlet) through the power cord or the transformer. The charging control module is received in the housing and is connected to the power receiving element so as to receive external electric power and control charging of the fast energy storage element. The fast energy storage element (e.g., a supercapacitor or any rapidly rechargeable components) is received in the housing and is connected to the charging control module. The fast energy storage element is configured for storing electricity and for providing output electricity when discharged. The warning element (e.g., a light-emitting diode, a buzzer, or a vibrator) is connected to the fast energy storage element and can generate a warning signal (e.g., a light signal, a warning sound, or vibrations) upon receiving the output electricity. The technical features of the present invention are such that the fast energy storage element of the rapidly rechargeable warning device can be rapidly charged through the cigarette lighter socket of a car, which socket is connected to a power source of the car, or through a transformer connected to an indoor power outlet. Thus, the money otherwise required for buying one-time batteries can be saved, and the user does not have to wait a long time for the charging operation of the rechargeable batteries to complete. The present invention not only significantly increases the timeliness and convenience in utilizing the warning devices, but also prevents pollution and a waste of resources which may otherwise result from using one-time batteries in large quantities. 
     Another object of the present invention is to provide the foregoing warning device, wherein the warning device further includes a voltage boosting module received in the housing and connected to the fast energy storage element. When the fast energy storage element is discharged, the voltage boosting module receives, and then increases the voltage level of the output electricity of the fast energy storage element, so as to provide the voltage required by the warning element to generate the warning signal. 
     Still another object of the present invention is to provide the foregoing warning device, wherein the warning device further includes an output control module connected between the voltage boosting module and the warning element. The output control module is configured for adjusting the current and voltage to be outputted to the warning element as well as the output frequency, so as for the warning element to generate various warning signals. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The structure and advantages of the present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a schematic structural diagram of the elements of the present invention; 
         FIG. 2  is a circuit diagram of the voltage boosting module in the present invention; 
         FIG. 3  is another circuit diagram of the voltage boosting module in the present invention; 
         FIG. 4  is a perspective view of the first preferred embodiment of the present invention; and 
         FIG. 5  is a perspective view of the second preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The conventional warning devices can not emit but reflect the light. Those improved and powered by batteries often suffer from loss of battery power, thus requiring users to spend extra money on one-time batteries for replacement. Aside from the inconvenience of frequent battery replacement, the massive use of one-time batteries is a waste of resources and causes pollution. Even if a warning device is powered by a rechargeable battery, the fact that rechargeable batteries nowadays are not designed to be rapidly charged with a large current leads to a time-consuming charging process that is of little help in case of emergency. In consideration of this, the inventor came up with the idea of equipping a warning device with a fast energy storage element which allows the warning device to be fully charged within a short time. Hence, a waste of resources and pollution can be prevented while the timeliness and convenience in utilizing the warning device are effectively increased. 
     The present invention discloses a rapidly rechargeable warning device. Please refer to  FIG. 1  for a schematic structural diagram of the elements of the present invention. The warning device  1  shown in  FIG. 1  includes a housing  10 , a power receiving element  11 , a charging control module  12 , a fast energy storage element  13 , a voltage boosting module  14 , a warning element  15 , and an output control module  16 . The power receiving element  11 , which is provided on the housing  10 , is configured for connecting with a power cord  17  or a transformer  18  and thereby connecting to an external power source (e.g., the cigarette lighter socket of a car or an indoor power outlet). In practice, it is also feasible for the power cord  17  or the transformer  18  to be directly fixedly connected to the power receiving element  11 . The charging control module  12  is received in the housing  10  and is connected to both the power receiving element  11  and the fast energy storage element  13 , so as to receive electricity from the external power source and charge the fast energy storage element  13 . The charging control module  12  can adjust the charging voltage and current while detecting the voltage of the fast energy storage element  13  and stop charging once the voltage of the fast energy storage element  13  reaches a predetermined voltage level. For example, assume the fast energy storage element  13  is a supercapacitor whose capacity equals to 3 volts (V)×100 Farads (F), the voltage across which is brought to 3 V by a voltage divider circuit, and on which fast charging is performed with a 10-ampre (A) current. When the voltage of the fast energy storage element  13  is detected to have reached 3 V, the charging control module  12  cuts off the electricity transmitted from the external power source and thereby stops charging the fast energy storage element  13 . The fast energy storage element  13  is received in the housing  10  and can receive and store the electricity transmitted from the charging control module  12 . When discharged, the fast energy storage element  13  provides output electricity. 
     Referring to  FIG. 1 , the fast energy storage element  13  in the present invention can be a supercapacitor or any kind of energy storage components that can be recharged with large current. A so-called supercapacitor—also known as golden capacitor, or double-electric layer capacitor—is an electrochemical capacitor of high energy density, as disclosed in further detail below with reference to the aforesaid example in which the fast energy storage element  13  is a supercapacitor having a capacity of 3 V×100 F. When the fast energy storage element  13  is charged with a current of 10 A, the required charging time can be determined as follows. The energy that the supercapacitor can store when fully charged is W=½×C×V 2 =½×100×3 2 =450 joules (J), where C and V are the capacitance and voltage of the fast energy storage element  13  respectively. Then, the time required for charging with the 10-A current can be obtained from ∫I×V(t)dt≈I×ΔV×t=10×1.5×t=450 J, where t is the charging time, I is the charging current, V(t) is the voltage across the supercapacitor, and ΔV is the average voltage drop during the charging process. The charging time t thus obtained is 30 seconds, meaning that it takes only about 30 seconds to fully charge the 100-F supercapacitor. 
     Referring again to  FIG. 1 , the voltage boosting module  14  is received in the housing  10  and is connected to the fast energy storage element  13 . When the fast energy storage element  13  is discharged, the voltage boosting module  14  receives the output electricity of the fast energy storage element  13  and increases the level value of the output electricity. Assume the fast energy storage element  13  is a 3-V supercapacitor outputting to a load of 2 V. When the voltage of the fast energy storage element  13  is lower than 2 V, the fast energy storage element  13  can no longer drive the load, despite the electricity remaining in the fast energy storage element  13 . By means of the voltage boosting module  14 , the lower-than-2 V voltage of the energy remaining in the fast energy storage element  13  can be raised above 3 V, allowing the fast energy storage element  13  to continue outputting to the load. In other embodiments of the present invention, the voltage boosting module  14  may be dispensed with such that the fast energy storage element  13  supplies electricity directly to the warning element  15  (i.e., the load). In that case, the unusable electricity left in the fast energy storage element  13  will be more than when the voltage boosting module  14  is present. 
     Please refer to  FIGS. 2 and 3  in conjunction with  FIG. 1 , wherein  FIGS. 2 and 3  show a common example of the circuitry of the voltage boosting module  14 . The voltage boosting module  14  includes an energy storage element B 0 , an inductor L 0 , a diode D, a switch S, and an output capacitor C 0 . The inductor L 0  has one end connected to one end of the switch S and the anode of the diode D, and the other end connected to the positive end of the energy storage element B 0 . The cathode of the diode D is connected to one end of the output capacitor C 0 . The output capacitor C 0  is connected to a load R in parallel. The other end of the switch S is connected to the other end of the output capacitor C 0  and the negative end of the energy storage element B 0 . In  FIG. 2 , in which the switch S is closed (i.e., turned on), the voltage V B  of the energy storage element B 0  flows through the inductor L 0 ; as a result, electric energy W L  is stored in the inductor L 0  (W L =½×L×I 2 , where L is the inductance of the inductor L 0 , and I is the current through the inductor L 0 ). Referring to  FIG. 3 , when the switch S is opened (i.e., turned off), the energy storage element B 0  charges the output capacitor C 0  such that the capacitor C 0  stores electric energy W 0  (W 0 =½×C×V B   2 , where C is the capacitance of the capacitor C 0 , and V B  is the voltage of the energy storage element B 0 ). In the meantime, the inductor L 0  charges the output capacitor C 0 , too. Therefore, the electric energy of the output capacitor C 0  will be W C =½×C×V C   2 =½×C×V B   2 +½×L×I 2 , in which the voltage V C  of the capacitor C 0  can be derived from V C   2 =V B   2 +L/C×I 2 . Now that the energy storage element B 0  and the inductor L 0  charge the capacitor C 0  simultaneously, the voltage V C  of the capacitor C 0  becomes higher than the voltage V B  of the energy storage element B 0 , and a voltage boosting effect is thus achieved. 
     Referring again to  FIG. 1 , the output control module  16  of the warning device  1  is received in the housing  10  and is connected to the voltage boosting module  14  so as to receive the output electricity of the voltage boosting module  14 . The output control module  16  is also connected to the warning element  15  so as to transmit electricity to and control the operation of the warning element  15 . For example, when the warning element  15  is a light-emitting diode, the output control module  16  may be configured to adjust its output voltage and current to the warning element  15 , as well as the output frequency and time, thus enabling various warning signal modes of the warning element  15 , e.g., causing the warning element  15  to flash intermittently, rapidly, cyclically, at varying speeds, or continuously. In a different embodiment of the present invention where the output control module  16  is omitted, the warning element  15  is directly connected to the voltage boosting module  14  and therefore has only one warning signal mode. Furthermore, the warning element  15  may be a buzzer  151  or a vibrator  152 , instead of the light-emitting diode  150 . In short, the output control module  16 , if present, can deliver the boosted output electricity of the voltage boosting module  14  to the warning element  15  and switch the warming signal modes thereof, for example by changing the flashing frequency of a light signal, the decibel level and frequency of a warning sound, or the frequency and the number of times of vibrations. 
     In the first preferred embodiment of the present invention as shown in  FIG. 4 , the warning device  4  is implemented as a warning triangle. For the sake of simplicity,  FIG. 4  shows only the housing  40  and the warning elements  45  of the warning device  4 , leaving out the charging control module, the fast energy storage element, and the voltage boosting module. In the first preferred embodiment, the warning elements  45  are light-emitting diodes, and the housing  40  of the warning device  4  is provided with at least one light guide element  48  corresponding in position to the warning elements  45  (with three light guide elements  48  shown in  FIG. 4 ). The light guide elements  48  may be a light guide plate, light strip, light pipe or light bar, or blended with a light diffusing material which can evenly scatter the light emitted by the warning elements  45 . Further, the power receiving element (not shown) of the warning device  4  and the power cord  47  may be integrated as a single unit, e.g., as a plug of an automobile power cord. In that case, the plug may be received in the housing  40  when not in use and is connected to the cigarette lighter socket of a car during the charging process in order to receive electricity from a power source of the car. 
     Please refer to  FIG. 5  for the second preferred embodiment of the present invention. The warning device  5  is a traffic baton, whose charging control module and voltage boosting module are not shown in the drawing.  FIG. 5  shows only the housing  50 , the power receiving element  51 , the fast energy storage element  53 , and the warning element  55  of the warning device  5 , without the wiring therebetween. As in the first preferred embodiment, the warning device  5  can be connected to the cigarette lighter socket of a car through an automobile power cord (i.e., the power cord  57 ) in order to receive electricity from a power outlet of the car. In addition, the warning device  5  can be connected to an indoor power source through a transformer and receive electricity from the indoor power source. Apart from the two warning devices demonstrated in the first and the second preferred embodiments, the technical features of the present invention are equally applicable to warning lights, warning signs, indication signs, light-emitting safety helmets, light-emitting safety vests, and so forth. 
     Referring back to  FIG. 1 , when the warning device  1  is needed for use in an emergency, the technical features of the present invention allow the fast energy storage element  13  in the warning device  1  to be rapidly charged from an external power source through the cigarette lighter socket of a car or an indoor power outlet. Thus, the need to buy one-time batteries is eliminated, and the charging process can be completed in a short time. The present invention greatly increases the timeliness and convenience in utilizing the warning device  1  while preventing pollution and a wasteful use of resources. It should be pointed out that the voltage boosting module  14  and/or the output control module  16  may be dispensed with or replaced by other electronic elements or circuits, and yet the intended effects of the present invention are still achievable to some extent. Therefore, all variations and modifications readily conceivable by a person skilled in the art should be viewed as equivalent changes of the present invention and encompassed by the appended claims.