Patent Publication Number: US-2009237919-A1

Title: Illuminating device

Description:
TECHNICAL FIELD 
     The present invention relates to an illuminating device, and particularly to an illuminating device using dual power supply system. 
     DISCUSSION OF RELATED ART 
     Light emitting diodes (LEDs) have many advantages, such as high luminance, low power consumption, compatibility with integrated circuits, long-term reliability, and environmental friendliness so that LEDs have become widely used as light source. 
     LED devices are generally powered by commercial power. Input of the LED devices is direct current (DC), which is commutated from alternating current (AC) of the commercial power. However, when commercial power is cut-off, the LED devices also stop working, which causes inconvenience to its users. 
     What is needed therefore, is an illuminating device to overcome the above described shortcomings. 
     SUMMARY 
     An illuminating device, includes a board, a plurality of lights, a rechargeable battery, a first circuit, a second circuit, and a switch. The board has a first surface and a second surface at an opposite side of the board to the first surface. The light sources are mounted on the first surface of the board. The rechargeable battery is mounted on the second surface of the board. The first circuit is configured for electrically connecting the light sources to mains power. The second circuit is configured for electrically connecting the light sources to the rechargeable battery. The switch is configured for controlling the light sources to be selectively connected to the first circuit or the second circuit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present illuminating device can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present illuminating device. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a schematic view of an illuminating device in accordance with a first embodiment. 
         FIG. 2  illustrates a circuit diagram of the illuminating device in  FIG. 1 . 
         FIG. 3  is a schematic view of an illuminating device in accordance with a second embodiment. 
         FIG. 4  illustrates a circuit diagram of the illuminating device in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Referring to  FIGS. 1 and 2 , an illuminating device  100  in accordance with a first embodiment is shown. The illuminating device  100  includes a body  110  having a first surface  1100  and a second surface  1102 , at least one light sources  120  mounted on the first surface  1100  of the body  110 , and a power supply  150  electrically connected with the light sources  120 . The power supply  150  can be mounted on the second surface  1102  of the body  110 . 
     The power supply  150  includes an electrical connector  131 , an AC-DC rectifier  132  electrically connected to the electrical connector  131 , a switch  133  for the AC-DC rectifier  132 , and a driving circuit  134  electrically connected to the switch  133 . The driving circuit  134  is electrically connected with the light source  120 . In the present embodiment, the light source  120  is an LED light source. 
     The power supply  150  further includes a commercial power  101  and a battery  140 . The commercial power  101  is electrically connected to the electrical connector  131 . The rectifier  132  is configured for converting alternating current (AC) to direct current (DC). The rectifier  132  may be made of solid state diodes, vacuum tube diodes, mercury arc valves, and other components. The commercial power  101 , the electrical connector  131 , the rectifier  132 , the switch  133 , and the driving circuit  134  together form a first circuit 
     The battery  140  is electrically connected to the switch  133 . The battery  140 , the switch  133 , and the driving circuit  134  form a second circuit II. 
     The switch  133  is selectively connected with the first circuit I or the second circuit II. When the switch  133  connects with the first circuit I, the light source  120  can be powered by the commercial power  101 . When the switch  133  connects with the second circuit II, the light source  120  can be powered by the battery  140 . 
     The switch  133  can includes a sensing circuit  1330 . The sensing circuit  1330  is configured for sensing whether there is electricity flowing from the commercial power  101  to the light source  120 . When the sensing circuit  1330  detects there is electricity flowing from the commercial power  101  to the light source  120 , the sensing circuit  1330  sends a signal to the switch  133  to control the switch  133  to disconnect with the battery  140 , so that the light source  120  is only powered by the commercial power  101 . When the sensing circuit  1330  detects there is no electricity flowing from the commercial power  101  to the light source  120 , the sensing circuit  1330  sends a signal to the switch  133  to control the switch  133  to connect with the battery  140 , so that the light source  120  is only powered by the battery  140 . 
     The battery  140  can be a rechargeable battery, also known as a storage battery. The battery  140  can be charged by the commercial power  101 . 
     The power supply  150  further includes a receiving module  135 . The receiving module  135  is electrically connected to the rectifier  132  and the switch  133 . The receiving module  135  is configured for receiving controlling signals or commands from external device, such as a remote controller. The receiving module  135  sends the controlling signals or commands to the driving circuit  134  to control the intensity of the light source  120  or control the light source  120  to be turned on/off. 
     The driving circuit  134  further includes a sensing control circuit  1340  electrically connected to the battery  140 . The sensing control circuit  1340  is configured for sensing the charge capacity of the battery  140  when the battery is in working mode, and controlling the amount of electricity supplied to the light source  120  by the battery  140 , thereby lasting the lighting hours of the light source  120 . When the sensing control circuit  1340  determines that the charge capacity of the battery  140  is less than a predetermined charge capacity, the sensing control circuit  1340  generates a control signal to the driving circuit  134 . The driving circuit  134  then decreases the amount of electricity supplied to the light source  120 . 
     In summary, the power of the illuminating device  100  can be selectively supplied by the commercial power  101  and the battery  140 . Under normal conditions, the light sources  120  are lit by the commercial power  101 , and the battery  140  is in a charge state. In the event of a commercial power outage, the battery  140  can be used as a backup power source to power the light sources  120 . 
     Referring to  FIGS. 3 and 4 , an illuminating device  200  in accordance with a second embodiment is shown. The illuminating device  200  includes a body  110 , at least one light sources  120  mounted on the body  110 , an indicating lamp  270  mounted on the body  110 , and a power supply  250  electrically connected with the light sources  120  and the indicating lamp  270 . In the present embodiment, the indicating lamp  270  can emit lights shaped as an arrow. 
     In the second embodiment, the power supply  250  is substantially similar with the power supply  150  of the first embodiment, the difference is that the power supply  250  further includes a switch control circuit  260  electrically connected between the indicating lamp  270  and the battery  140 . The battery  140  also electrically connects to the electrical connector  131 . The switch control circuit  260  is configured for sensing whether there is electricity flowing from the commercial power  101  to the light source  120 . When the switch control circuit  260  detects there is electricity flowing from the commercial power  101  to the light source  120 , the switch control circuit  260  disconnects with the battery  140  and the indicating lamp  270 . When the switch control circuit  260  detects there is no electricity flowing from the commercial power  101  to the light source  120 , the switch control circuit  260  connects with the battery  140  and the indicating lamp  270 . That is, in the event of commercial power outage, the indicating lamp  270  can be lit by the battery  240  to denote a way out of a building for people. 
     While certain embodiments have been described and exemplified above, various other embodiments from the foregoing disclosure will be apparent to those skilled in the art. The present invention is not limited to the particular embodiments described and exemplified but is capable of considerable variation and modification without departure from the scope of the appended claims.