Lighting apparatus

The present invention is related to a lighting apparatus, and more particularly related to a lighting apparatus with a protection design.

Electroluminescence, an optical and electrical phenomenon, was discover in 1907. Electroluminescence refers the process when a material emits light when a passage of an electric field or current occurs. LED stands for light-emitting diode. The very first LED was reported being created in 1927 by a Russian inventor. During decades' development, the first practical LED was found in 1961, and was issued patent by the U.S. patent office in 1962. In the second half of 1962, the first commercial LED product emitting low-intensity infrared light was introduced. The first visible-spectrum LED, which limited to red, was then developed in 1962.

After the invention of LEDs, the neon indicator and incandescent lamps are gradually replaced. However, the cost of initial commercial LEDs was extremely high, making them rare to be applied for practical use. Also, LEDs only illuminated red light at early stage. The brightness of the light only could be used as indicator for it was too dark to illuminate an area. Unlike modern LEDs which are bound in transparent plastic cases, LEDs in early stage were packed in metal cases.

With high light output, LEDs are available across the visible, infrared wavelengths, and ultraviolet lighting fixtures. Recently, there is a high-output white light LED. And this kind of high-output white light LEDs are suitable for room and outdoor area lighting. Having led to new displays and sensors, LEDs are now be used in advertising, traffic signals, medical devices, camera flashes, lighted wallpaper, aviation lighting, horticultural grow lights, and automotive headlamps. Also, they are used in cellphones to show messages.

A Fluorescent lamp refers to a gas-discharge lamps. The invention of fluorescent lamps, which are also called fluorescent tubes, can be traced back to hundreds of years ago. Being invented by Thomas Edison in 1896, fluorescent lamps used calcium tungstate as the substance to fluoresce then. In 1939, they were firstly introduced to the market as commercial products with variety of types.

In a fluorescent lamp tube, there is a mix of mercury vapor, xenon, argon, and neon, or krypton. A fluorescent coating coats on the inner wall of the lamp. The fluorescent coating is made of blends of rare-earth phosphor and metallic salts. Normally, the electrodes of the lamp comprise coiled tungsten. The electrodes are also coated with strontium, calcium oxides and barium. An internal opaque reflector can be found in some fluorescent lamps. Normally, the shape of the light tubes is straight. Sometimes, the light tubes are made circle for special usages. Also, u-shaped tubes are seen to provide light for more compact areas.

Because there is mercury in fluorescent lamps, it is likely that the mercury contaminates the environment after the lamps are broken. Electromagnetic ballasts in fluorescent lamps are capable of producing buzzing mouse. Radio frequency interference is likely to be made by old fluorescent lamps. The operation of fluorescent lamps requires specific temperature, which is best around room temperature. If the lamps are placed in places with too low or high temperature, the efficacy of the lamps decreases.

In real lighting device design, details are critical no matter how small they appear. For example, to fix two components together conveniently usually brings large technical effect in the field of light device particularly when any such design involves a very large number of products to be sold around the world.

In addition, safety is always an important factor. Lighting devices involves electricity providing, which may cause electric shock to users. Such factor needs to be carefully considered as a necessary aspect on considering and designing new solutions.

In some embodiments, a lighting apparatus includes a first electrode, a second electrode, a lighting source, a rectifier, a driver and an electric shock prevention circuit.

The first electrode and the second electrode receive an external power source. The external power source is either an alternating current or a direct current.

The light source has multiple LED modules.

The rectifier is used for rectifying the external power source to a rectified power.

The driver is used for converting the rectified power to a driving current supplying to the light source.

In some embodiments, the driver has a PI filter and a direct current converter. The PI filter is connected to the electric shock prevention circuit. The PI filter includes an inductor, a capacitor and two resistors for filtering the rectifier power to a smooth direct current.

The electric shock prevention circuit is disposed between the rectifier and the driver for stopping the rectified power to the driver if a human touch of the first electrode and the second electrode is detected by turning off a check gate. When the external power source is the alternating current, a capacitor connecting to the alternating current is used for turning on the checking gate to supply the rectified power to the driver. When the external power source is the direct current, a diode connecting to the direct current is used for turning on the checking gate to supply the rectified power to the driver.

In some embodiments, the electric shock prevention circuit detects impedance of the first electrode and the second electrode for checking whether there is the human touch.

In some embodiments, the electric shock prevention circuit detects the rectifier power to determine whether the human touch exists.

In some embodiments, the lighting apparatus includes a tubular housing, a first end cap and a second end cap.

The tubular housing is used for enclosing the light source and for allowing a light emitted from the light source passing through the tubular housing. The first end cap and the second end cap are attached to a tube socket and are connected to the first electrode and the second electrode.

In embodiments, the light source is made as a module with a magnet connector for attaching to the tubular housing.

In embodiments, the driver is made as a module attached to the tubular housing via magnet connection.

In some embodiments, there is a safety buckle for further fixing a connection between the light source and the tubular housing.

In some embodiments, there are aligning structures for aligning an electric connection between the light source and the tubular housing.

Different sections of the LED modules are provided with separate heat dissipation bars.

A heat of the heat dissipation bars is lead to a middle portion of the tubular housing.

The direct current is from an urgent battery.

The lighting apparatus also includes a motion sensor connected to the electric shock prevention circuit. When the motion sensor detects a motion from a user, the socket prevention circuit stops sending the rectified power to the driver.

In some embodiments, the electric shock prevention circuit sets a first operation mode and a second operation mode. In the first operation mode, a test current smaller than the rectified power is sent to the driver in the first mode when users just install the lighting apparatus. After a predetermined time period, the electric shock prevention circuit switches the second operation mode for routing all the rectified power to the driver.

A battery is provided for providing the test current to turn on the light source in the first operation mode.

In some embodiments, a lighting apparatus includes a manual switch. Users turn on or turn off the switch when replacing the lighting apparatus. The driver stops providing the driving current when the manual switch is turned off.

In some embodiments, a high temperature indicator for warning users when a temperature of the lighting apparatus is higher than a threshold.

The high temperature indicator is a color changing tape attached on a surface of a light passing cover enclosing the light source.

In some embodiments, a temperature sensor is disposed for detecting the temperature of the lighting apparatus. Users turns on a manual switch and the driver enters a sleep mode and uses the temperature indicator informing the users when the temperature is under a threshold.

In some embodiments, the driver is synchronized with another driver of a neighboring lighting apparatus and turns on the light source under a frequency when the another driver of the neighboring lighting apparatus does not turn on another light source of the neighboring lighting apparatus.

In some embodiments, a light detector is used for performing the synchronization with the neighboring lighting apparatus.

With the designs, the lighting apparatus, no matter it is a light bulb, a light tube or other lighting devices, is safer while maintaining low cost on manufacturing.

FIG. 1 is an architecture diagram of an embodiment.

FIG. 2 is a circuit diagram showing an example.

FIG. 3 shows another architecture diagram of an embodiment.

FIG. 4 shows a light tube example.

FIG. 5 shows another light tube example.

FIG. 6 shows a heat dissipation structure.

FIG. 7 shows an anti-flicking embodiment.

In FIG. 3 , a lighting apparatus includes a first electrode 381 , a second electrode 382 , a lighting source 383 , a rectifier 384 , a driver 385 and an electric shock prevention circuit 386 .

The first electrode 381 and the second electrode 382 receives an external power source. The external power source is either an alternating current or a direct current.

The light source 383 has multiple LED modules 3831 .

The rectifier 384 is used for rectifying the external power source to a rectified power.

The driver 385 is used for converting the rectified power to a driving current supplying to the light source 383 .

The electric shock prevention circuit 386 is disposed between the rectifier 384 and the driver 385 for stopping the rectified power to the driver 385 if a human touch of the first electrode 381 and the second electrode 382 is detected by turning off a checking gate 389 . When the external power source is the alternating current, a capacitor 391 connecting to the alternating current is used for turning on the checking gate 389 to supply the rectified power to the driver 385 . When the external power source is the direct current, a diode 392 connecting to the direct current is used for turning on the checking gate 389 to supply the rectified power to the driver 385 .

In FIG. 3 , the driver 385 has a PI filter 388 and a direct current converter 393 . The PI filter 388 is connected to the electric shock prevention circuit 386 . The PI filter 388 includes an inductor, a capacitor and two resistors for filtering the rectifier power to a smooth direct current.

In some embodiments, the electric shock prevention circuit detects impedance of the first electrode and the second electrode for checking whether there is the human touch.

In some embodiments, the electric shock prevention circuit detects the rectifier power to determine whether the human touch exists.

In FIG. 4 , the lighting apparatus includes a tubular housing 482 , a first end cap 483 and a second end cap 484 .

The tubular housing 482 is used for enclosing the light source 481 and for allowing a light emitted from the light source 481 passing through the tubular housing 482 . The first end cap 483 and the second end cap 484 are attached to a tube socket 485 and are connected to the first electrode and the second electrode.

In FIG. 5 the light source 583 is made as a module with a magnet connector 582 for attaching to a magnet unit 581 of the tubular housing 584 .

In FIG. 5 , the driver 585 is made as a module attached to the tubular housing 584 via magnet connection.

In FIG. 5 , there is a safety buckle 587 connected to a socket 588 for further fixing a connection between the light source 583 and the tubular housing 584 .

In FIG. 5 , there are aligning structures 589 , 590 for aligning an electric connection between the light source 583 and the tubular housing 584 .

In FIG. 6 , different sections 601 , 602 , 603 of the LED modules are provided with separate heat dissipation bars 611 , 612 , 613 .

In some embodiments, heat of the heat dissipation bars is lead to a middle portion of the tubular housing.

In some embodiments, the direct current is from an urgent battery.

In FIG. 4 , the lighting apparatus also includes a motion sensor 487 connected to the electric shock prevention circuit. When the motion sensor 487 detects a motion from a user, the socket prevention circuit stops sending the rectified power to the driver.

In some embodiments, the electric shock prevention circuit sets a first operation mode and a second operation mode. In the first operation mode, a test current smaller than the rectified power is sent to the driver in the first mode when users just install the lighting apparatus. After a predetermined time period, the electric shock prevention circuit switches the second operation mode for routing all the rectified power to the driver.

In some embodiments, a battery is provided for providing the test current to turn on the light source in the first operation mode.

In FIG. 4 , a lighting apparatus includes a manual switch 488 . Users turn on or turn off the manual switch 488 when replacing the lighting apparatus. The driver stops providing the driving current when the manual switch 488 is turned off.

In FIG. 4 , a high temperature indicator 489 for warning users when a temperature of the lighting apparatus is higher than a threshold.

In some embodiments, the high temperature indicator is a color changing tape attached on a surface of a light passing cover enclosing the light source.

In FIG. 4 , a temperature sensor 491 is disposed for detecting the temperature of the lighting apparatus. Users turns on the manual switch 488 and the driver enters a sleep mode and uses the temperature indicator 489 informing the users when the temperature is under a threshold.

In FIG. 7 , the driver 795 of a light tube device 793 is synchronized with another driver 794 of a neighboring lighting apparatus 791 and turns on the light source under a frequency when the another driver 794 of the neighboring light tube device 791 does not turn on another light source of the neighboring light tube device 791 .

In FIG. 7 , a light detector 793 is used for performing the synchronization with the neighboring light tube device 791 .

Please refer to FIG. 1 , which illustrates a circuit diagram of an embodiment of a lighting apparatus.

There are single end LED light tubes and double ended LED light tubes. For the later type of LED light tubes, it is possible when people install or remove the LED light tubes, they get electricity shocked. Therefore, an electric shock prevention module is used for detecting whether there is a human touch for the electrodes, e.g. impedance parameters, which may cause electric shock and for stopping electricity to get into the human.

When the human touch is found, there is a high impedance in the electric shock prevention circuit for making the lighting apparatus in an open mode, i.e. no electricity is further supplied the lighting apparatus to prevent human getting electricity shocked. However, when there are both alternating current power input and direct current power input, the electric shock prevention circuit may fail to function on both modes. For example, the electric shock prevention circuit may function under an alternating current but fails to respond under a direct current, e.g. from an urgent battery. This technical problem needs to solved to provide a safer lighting apparatus.

In FIG. 1 , a power circuit includes a rectifier 10 , a first transistor 20 , an electric shock prevention circuit 30 and a driver 40 .

A first input end of the rectifier 10 is used as a positive input of the power circuit. The second input end of the rectifier 10 is used as a negative input of the power circuit. The rectifier 10 supplies a first voltage signal on a positive input end and is connected to ground in the negative output end.

The first transistor 20 is connected between the negative output and ground of the power circuit.

An input end of the electric prevention circuit 30 is connected to a positive output end of the rectifier 10 . An output end of the electric shock prevention circuit 30 is connected to a control end of the first transistor 20 .

The electric shock prevention circuit 10 is used for opening or closing the circuit by controlling turning-on or turning-off of the first transistor 20 for prevention human getting electric shocked.

The input end of the driver 40 is connected to the positive output end of the rectifier 10 . The positive output end of the driver 40 is connected to the positive output end of the power circuit. The driver 40 provides power to the LED+ and LED− ends of a light source.

The rectifier may be a full bridge rectifier for converting a sine curve input of 50 Hz or 60 Hz alternating current to a half wave 100 Hz or 12 Hz voltage signal.

In FIG. 2 , an example circuit diagram is provided.

The electric prevention circuit includes a driver module 31 and a direct current driver module 32 . The alternating driver module 31 has an input end connected to a positive output end of a rectifier 10 . The voltage output end of the alternating driver module 31 provides a second voltage signal. The alternating driver module 31 has a driver end connected to a control end of the first transistor. The alternating driver module 31 is used for controlling the first transistor 20 to open for preventing electric shock when the power signal is an alternating current signal.

The input end of the direct current driver module 32 is connected to a positive output end of the rectifier 10 . The direct current driver module 32 has a direct current input end connected to a voltage output end of the electric shock prevention circuit 30 .

The output end of the direct current driver module 32 is connected to the control end of the first transistor 20 . The direct current driver module 32 controls the first transistor 20 to open for preventing electric shock when the input power is direct current.

With the alternating driver module 31 and the direct current driver module 32 , the power circuit works normally in both alternating current mode and direct current mode.

The operation is explained as follows.

When the power signal is an alternating current signal, a half wave direct current signal output by the rectifier 10 is sent to the electric shock prevention module. When the alternating driver module 31 receives the half wave direct current signal, the driver end of the alternating driver module 31 outputs a high voltage control signal to the control end of the first transistor 20 to provide an turning-on voltage to the first transistor for closing the power circuit to work normally providing power to the LED modules.

When an impedance is detected in the electric network, the electric shock prevention circuit shows a high impedance status, and the driver end of the alternating driver module 31 no more outputs a high voltage signal and thus turns off the first transistor 20 so that the power circuit is open to prevent electric shock.

When the input power source is a direct current signal, the voltage output end of the electric shock prevention circuit outputs a direct voltage signal to the direct current input end of the direct current driver module 32 , then passing through the direct current driver module 32 and outputs a high voltage to the control end of the first transistor 20 to turn on the first transistor 20 so that the power circuit is closed and work normally providing the LED modules to emit light.

By using such designs, the lighting apparatus is able to function normally in both direct current mode and alternating current mode. The first transistor works correctly in both modes, making the lighting apparatus safer.

In FIG. 2 , the alternating driver module 31 includes an electric shock prevention chip U 1 , a first diode D 1 , a second diode D 2 and a capacitor C 1 .

The positive end of the first diode D 1 is used as an input end of the alternating driver module 31 . The negative end of the first diode D 1 is connected to HV end (High voltage enabling end) of the electric shock prevention chip U 1 for providing a starting voltage for the electric shock prevention chip U 1 when the rectifier 10 receives a direct current or an alternating current power signal.

The positive end of the second diode D 2 is connected to the GATE end of the electric shock prevention chip U 1 . the negative end of the second diode D 2 is used as a driver end of the alternating driver module 31 . The first end of the first capacitor C 1 is connected to a power output end and a second end of the first capacitor is connected to ground.

In FIG. 2 , the direct current driver module 32 includes a second capacitor C 2 , a third capacitor C 3 , a first resistor R 1 , a second resistor R 2 , a third resistor R 3 , a third diode D 3 , a fourth diode D 4 and a second transistor Q 2 .

A first end of the second capacitor C 2 is used as an input end of the direct current driver module 32 . A second end of the second capacitor C 2 is connected to a positive end of the third diode D 3 and the first end of the first resistor R 1 . The third diode D 3 has a negative end connected to the control end of the second transistor Q 2 .

The first end of the second resistor R 2 is used as a direct current input end of the direct current driver module 32 . The second end of the second resistor R 2 is connected to the input end of the second transistor Q 2 , the first end of the third capacitor C 3 , and the positive end of the fourth diode D 4 . the negative end of the fourth diode D 4 is connected to a first end of the third resistor R 3 .

The negative end of the fourth diode D 4 is used as a direct current output end of the direct current driver module 32 . The second end of the first resistor R 1 , the output end of the second transistor Q 2 , the second end of the third capacitor C 3 and the second end of the third resistor are connected to ground.

When the power circuit is supplied with a power signal of a direct current or an alternating current, the electric shock prevention chip U 1 determines whether the power signal is a direct current signal or an alternating current signal. This is understood by persons skilled in the art and not repeated the details for brevity.

When the power signal is a direct current signal, the high voltage activation end HV of the electric shock prevention chip U 1 provides voltage output to a voltage output end VCC. The high voltage activation end HV is not connected to the ground GND so that the gate control end GATE does not output control signals. The circuit of the second resistor R 2 and the fourth diode D 4 form a path providing a turning-on voltage to the first transistor Q 1 to close the power circuit to work normally.

When the power signal is an alternating signal, the high voltage activation end HV provides a voltage to the voltage output end VCC so that the voltage output end VCC outputting a second voltage signal. The high voltage activation end HV and the ground GND are connected so that the gate control end of the electric shock prevention chip U 1 is able to output a control signal for charging the first capacitor C 1 with the half wave direct current signal so as to provide a turning-on voltage to the second transistor Q 2 . When the second transistor Q 2 is turned on, the positive end of the fourth diode D 4 switches to a low voltage, and disconnect the fourth diode D 4 to separate the second voltage signal output by the electric shock prevention chip U 1 from the voltage output end and the control signal of the gate control end GATE of the electric shock prevention chip U 1 .

By sending a control signal from the gate control end GATE of the electric shock prevention chip U 1 to the control end of the first transistor Q 1 to turn on the first transistor Q 1 so that the power circuit is closed and works normally.

The first transistor Q 1 and the second transistor Q 2 may be MOS transistor or other quick response control switch. The electric shock prevention chip may be a BP5018J chip or compatible circuit.

In FIG. 2 , the power circuit also includes a filter circuit 50 . The filter circuit 50 has a positive end connected to a positive input end of the rectifier circuit 10 . The positive output end of the filter circuit 50 is connected to a positive end of the driver 40 . The negative output end of the filter circuit is connected to a negative output end LED− of the power circuit.

In FIG. 2 , the filter circuit 50 is a PI filter for satisfying EMC requirements.

The filter circuit 50 includes a fifth diode D 5 , a first inductor L 1 , a fourth resistor R 4 , a fourth capacitor C 4 and a fifth capacitor C 5 .

The positive end of the fifth diode D 5 is used as a positive input end of the filter circuit 50 . The negative end of the fifth diode D 5 is connected to a first end of the first inductor L 1 , the first end of the fourth resistor R 4 , the first end of the fourth capacitor C 4 .

The positive input end of the driver 50 is connected to a second end of the first inductor L 1 , a second end of the fourth resistor R 4 , a first end of the fifth capacitor C 5 .

The second end of the first inductor L 1 is used as the positive output end of the filter circuit 50 . The second end of the fourth resistor R 4 is connected to the first end of the fifth capacitor C 5 and the second end of the first inductor L 1 . The second end of the fourth capacitor C 4 is connected to the second end of the fifth capacitor C 5 , and the negative output end of the power circuit. The fifth diode D 5 may be a tap style or a quick recovery diode.

In FIG. 2 , the driver circuit 40 includes a driver chip U 2 , a sixth capacitor C 6 , a seventh capacitor C 7 , a eighth capacitor C 8 , a ninth capacitor C 9 , a tenth capacitor C 10 , a fifth resistor R 5 , a sixth resistor R 6 , a seventh resistor R 7 , an eighth resistor R 8 , a ninth resistor R 9 , a tenth resistor R 10 , an eleventh resistor R 1 , a sixth diode D 6 and a second inductor L 2 .

The fifth pin 5 , the sixth pin 6 , the seventh pin 7 , the eighth pin 8 of the driver chip U 2 are connected to the second end of the first inductor L 1 .

The second end of the first inductor L 1 is connected to a first end of the seventh capacitor C 7 . the second end of the seventh capacitor C 7 is connected to a first end of the eighth capacitor C 8 . The second end of the eighth capacitor C 8 is connected to a positive output end LED+, and the first end of the tenth capacitor C 10 .

The first end of the sixth capacitor C 6 is connected to a power management end VCC of the driver chip U 2 . The second end of the sixth capacitor C 6 is connected to ground.

The resistor sensing end CS of the driver chip US is connected to the first end of the eighth resistor R 8 , the first end of the ninth resistor R 9 and a first end of the second inductor L 2 . the second end of the ninth resistor R 9 and the second end of the eighth resistor R 8 are connected to ground.

The ZCD end of the driver chip U 2 is connected to the first end of the seventh resistor R 7 and the first end of the fifth resistor R 5 .

The second end of the seventh resistor R 7 is connected to ground. The second end of the fifth resistor R 5 is connected to a first end of the sixth resistor R 6 .

The second end of the sixth resistor R 6 is connected to a second end of the eighth capacitor C 8 , the positive output end LED+, and the first end of the tenth capacitor C 10 .

The first end of the ninth capacitor C 9 is connected to ground. The positive end of the sixth diode D 6 is connected to a first end of the eleventh resistor R 11 , the first end of the tenth resistor R 10 , the second end of the tenth capacitor C 10 , the input end of the first transistor Q 1 and the negative end LED− of the power circuit.

The negative end of the sixth diode D 6 is connected to ground. The second end of the eleventh resistor R 11 is connected to a second end of the ninth capacitor C 9 .

The second end of the tenth resistor R 10 is connected to the second end of the second inductor L 2 , the positive output end LED+ of the power circuit, the first end of the tenth capacitor C 10 .

In some other embodiments, the driver circuit may be a switch power circuit of separation form or non-separation form.

In FIG. 2 , when the power signal source is an alternating current, there is a relay FR 1 in the input end of the rectifier.

The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings.

The embodiments were chosen and described in order to best explain the principles of the techniques and their practical applications. Others skilled in the art are thereby enabled to best utilize the techniques and various embodiments with various modifications as are suited to the particular use contemplated.

Although the disclosure and examples have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the disclosure and examples as defined by the claims.