Abstract:
A method for controlling a remote LED lamp includes: using a memory unit ( 452 ) to record a standard value for indicating a normal environmental brightness and a reference value for indicating a normal LED brightness; using a first sensor ( 41 ) to detect real-time brightness of the environmental light and transmit a signal ( 31 ) indicating the real-time brightness to the memory unit; using the memory unit to compare the signal with the standard value to obtain a result; using a driving unit ( 451 ) to control the LED light lamp to be turned on/off according to the result.

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a light emitting diode (LED) lamp, and more particularly to an LED lamp incorporating a remote control device. 
     2. Description of Related Art 
     With the continuing development of scientific technology and the raise of people&#39;s consciousness of energy saving, LEDs have been widely used in the field of illumination due to their small size and high efficiency. It is well known that an LED street lamp with LEDs arranged side-by-side in large density generates a lot of heat when the LEDs emit light. Especially, a longtime, continuous use of the LED street lamp may result in the LEDs being overheated by heat accumulated in the LED street lamp, significantly reducing work efficiency and service life thereof. Furthermore, the LED street lamp is not required to be working all day long. 
     What is needed, therefore, is an LED lamp which can be controlled to work according to actual need. 
     SUMMARY 
     A method for controlling a remote LED lamp according to an exemplary embodiment includes: using a memory unit to record a standard value for indicating a normal environmental brightness and a reference value for indicating a normal LED brightness; using a first sensor to detect real-time brightness of the environmental light and transmit a signal indicating the real-time brightness to the memory unit; using the memory unit to compare the signal with the standard value to obtain a result; using a driving unit to control the LED light lamp to be turned on/off according to the result. 
     Other advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present apparatus 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 apparatus. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is an isometric, assembled view of an LED lamp in accordance with a first embodiment, wherein a cover is apart from the LED lamp. 
         FIG. 2  is similar to  FIG. 1 , but viewed from a different aspect. 
         FIG. 3  shows a block diagram of the LED lamp shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-2 , an LED lamp  100  in accordance with a first embodiment is shown. The LED lamp  100  is used as a street lamp for a lighting purpose. The LED lamp  100  includes a light source  10 , a heat sink  20  and a control unit  40 . The light source  10  is located on a front side of the heat sink  10  for emitting light. The control unit  40  is embedded into the heat sink  10  for detecting and controlling the working status of the light source  10 . 
     The heat sink  20  includes a base  21  and a plurality of fins  23 . The base  21  has an elongated and rectangular shape. The fins  23  extend outwardly from two lateral sides of the base  21 . A rectangular recess  211  is defined in a middle of the front side of the base  21 . A protrusion  25  is formed on a middle of the rear side of the base  21  and extends along the elongate direction of the base  21 . A circular hole  250  is defined through the protrusion  25  from top to bottom. A cluster of wires  50  is received in the hole  250 . The wires  50  are respectively connected with the light source  10  and the control unit  40  for supplying power and transmitting signals. 
     The light source  10  includes a plurality of LEDs  12  and a rectangular cover  15 . The LEDs  12  are received in the recess  211  and arranged side-by-side in large density. The cover  15  is used to cover the LEDs  12  for protecting the LEDs  12  from the external physical shock. The cover  15  is also be used to redirect light from the LEDs  12 . The cover  15  is made of transparent or translucent material, such as glass or plastic. 
     The control unit  40  includes first and second sensors  41 ,  42  and a control circuit  45 . The first and second sensors  41 ,  42  are used to detect brightness of light. The first sensor  41  is used to detect brightness of the environmental light so that the first sensor  41  is located in a position out of lighting range of the light source  10 . Furthermore, for reducing heat of the light source  10  transferred to the first sensor  41 , the first sensor  41  is located far away from the light source  10 . In the present embodiment, the first sensor  41  is located on the rear side of the heat sink  20 . 
     The second sensor  42  is used to detect the brightness of light emitted by the LEDs  12 . The second sensor  42  is located within the lighting range of the light source  10 . In the present embodiment, the second sensor  42  is located in the recess  211  of the front side of the heat sink  20  and near the LEDs  12 . 
     The control circuit  45  is located on the front side of the heat sink  20  and above the light source  10  with a distance therefrom. 
     Referring to  FIG. 3 , the control circuit  45  includes a driving unit  451 , a memory unit  452  and a communication unit  453 . The driving unit  451  is electrically connected with the light source  10  to control the light source  10  to be turned on/off. The memory unit  452  is electrically connected with the first and second sensors  41 ,  42  for recording standard values of normal environmental brightness of the environment and the LEDs  12  and signals and values generated by the first and second sensors  41 ,  42 , such as values of measured results of brightness of the environment and the LEDs  12 , values of lighting time of the light source  12 . Signals generated by the memory unit according to the values can be transmitted to a long-distance control center  200  via the communication unit  453  and the wires  50 . A password can be set up in the communication unit  453  so that the values in the memory unit  452  can not be obtained unless a verification is passed. 
     At first, the standard value for indicating a normal environmental brightness is recorded in the memory unit  452 . The reference value for indicating a normal brightness of the LEDs  12  is recorded in the memory unit  452 . The first and second sensors  41 ,  42  are then activated. The first sensor  41  is used to detect real-time brightness of the environmental light and transmits a signal  31  indicating the real-time brightness to the memory unit  452 . In the memory unit  452 , a result is obtained by comparing the signal  31  with the standard value to indicate whether the real-time brightness of the environmental light is bright enough or not. According to the result, the light source  10  will be determined to be turned on or turned off. For example, if value of the real-time brightness of the environmental light is less than the standard value, which means the brightness of the ambient light is not bright enough, the driving unit  451  sends a signal  37  to turn on the light source  10 , thereby providing an illumination for the environment. If value of the real-time brightness of the environmental light is more than the standard value, which means the brightness of the ambient light is bright enough, the driving unit  451  sends the signal  37  to turn off the light source  10 . Therefore, the light source  10  can be turned on/off according to actual brightness of the environmental light. Thus, electrical energy can be saved and the LEDs  12  can be prevented from working all day long. 
     When the light source  10  turns on, the second sensor  42  is used to detect real-time brightness of the LEDs  12  of the light source  10  and transfers a signal  33  indicating the real-time brightness of the LEDs  12  to the memory unit  452 . In the memory unit  452 , a result is obtained by comparing the real-time brightness of the LEDs  12  with the reference value to indicate the working status of the light source  10 . Furthermore, brightness, lighting time, flicker, or other abnormal state of the LEDs  12  can be detected by the second sensor  42  and sent to the memory unit  452 . If the light source  10  works abnormally, the control circuit  45  sends a signal  38  to the long-distance control center  200  to further indicate working state and position of the LED lamp  100 . Thus, the LED lamp  100  can be maintained as well. 
     Because the second sensor  42  is near the light source  10 , the heat generated by the LEDs  12  possibly exert an influence on the second sensor  42 , further resulting in measured error of the second sensor  42 . For enhancing measured precision of the second sensor  42 , the measured result of the second sensor  42  should be corrected. Because the first sensor  41  is far away from the light source  10  relative to the second sensor  42 , the first sensor  41  can be used as reference to correct the measured result of the second sensor  42 . 
     For example, the first and second sensors  41 ,  42  each are initialized to have an identical original fiducial value, and the original fiducial value of the first sensor  41  is recorded in the memory unit  452 . At each detection, the second sensor  42  sends the measured result and the real-time fiducial value to the memory unit  452 . Then, the memory unit  452  executes an operation to subtract the fiducial value of the first sensor  41  from the real-time fiducial value of the second sensor  42  to obtain a difference value. If the difference value is not zero, the second sensor  42  has a measured error. The measured result of the second sensor  42  then can be corrected by adding the difference value to or subtracting the difference value from the measured value. 
     In another case, the first and second sensors  41 ,  42  are initialized to have different original fiducial values. A first difference value between the two original fiducial values is recorded by the memory unit  452  at first. At each detection, the second sensor  42  sends the measured result and the real-time fiducial value to the memory unit  452 . The first difference value is added to or subtracted from the real-time fiducial value to obtain a registered value. Then, the memory unit  452  executes an operation to subtract the original fiducial value of the first sensor  41  from the registered value to obtain a second difference value. If the second difference value is not zero, the measured result of the second sensor  42  has an error, which can be corrected by adding the second difference value to or subtracting the second difference value from the measured value of the second sensor  42 . 
     In a word, the light source can be controlled to be turned on/off according to actual need in the environment by the control circuit  45 . A lot of electrical energy can be saved and the LEDs  12  can be prevented from being overheated. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.