WO2019041497A1

WO2019041497A1 - Alternating current-driven led lamp configured with heat-dissipating fins

Info

Publication number: WO2019041497A1
Application number: PCT/CN2017/107769
Authority: WO
Inventors: 潘伟雄
Original assignee: 广州怡泰照明电子科技有限公司
Priority date: 2017-08-31
Filing date: 2017-10-26
Publication date: 2019-03-07
Also published as: CN207196205U

Abstract

Provided is an alternating current-driven LED lamp configured with heat-dissipating fins. As a lampshade (10) of the lamp has fins (11) configured with heat-dissipating holes (111), the lamp can dissipate heat effectively without an additional heat sink. An adaptive driving circuit is disposed inside a lamp body. By means of controlling the number of LEDs that are turned on, the LEDs connected in series can automatically adapt to changes in a driving voltage. When the driving voltage is low, less LEDs are turned on, and when the driving voltage is high, more LEDs are turned on. As a result, the total voltage drop of the LEDs follows changes in the driving voltage. The LEDs can be connected to the mains through a simple control circuit and a simple current-limiting or constant-current circuit, and can function normally by employing extremely simple driving methods.

Description

AC driven fin type cooling LED lamp

Technical field

The present invention relates to the technical field of LEDs, and in particular to a photoelectric integrated LED lamp having a heat dissipation function.

Background technique

LED lamps have many advantages such as high energy conversion efficiency, fast switching response, long life, no radiation and low power consumption. They are widely used in more and more occasions. In some functional lighting fields, LED lighting replaces traditional light sources. Lighting is a general trend.

A problem exists in the prior art: an existing LED lamp is usually provided with a heat sink, an aluminum substrate is disposed under the heat sink, and a heat conductive adhesive is disposed between the heat sink and the aluminum substrate, and the aluminum substrate is disposed on the aluminum substrate An LED light source is fixed. The heat generated by the LED light source is transmitted to the thermal conductive adhesive through the aluminum substrate, and then transmitted to the heat sink through the thermal conductive adhesive, and finally dissipated through the heat sink, and the heat dissipation performance is poor.

The second problem of the prior art is that the LED driving power source generally adopts an AC to DC circuit such as flyback and LLC, and is composed of input filtering, rectification, constant current and control circuit, MOS tube, transformer, output rectification and filtering, etc. The circuit is complicated and the design is difficult, so the cost is high, and the cost of the good quality LED driving power supply is about 1.5~3 yuan/W. Since there are many circuit components, especially those with life limit such as electrolytic capacitors, the life of the driving power supply is limited, which limits the overall life of the LED lamp, and the power supply often fails when the LED lamp bead does not reach the service life. The advantages of long LED life have not been fully utilized. In addition, since the circuit operates in a high-frequency switching state, electromagnetic interference is inevitably generated, which may pollute the power grid and adversely affect the surrounding radio equipment. Therefore, the EMC design of the driving power source is also a major problem that plagues the engineer design process. There is an AC LED lamp on the market that does not need to drive the power supply. The method is to use the AC LED lamp bead (or the reversed common lamp bead) to directly connect to the mains via the resistor current limiting. The advantage of this method is that there is no need to drive the power supply. The cost is low and the life is not limited by the power supply. However, this method often uses a lot of LED lamp beads to connect to the mains after the series connection, so that the total voltage drop of the LED lamp bead is close to the rms value of the mains, which leads to a fatal defect is stroboscopic It is more powerful, and the power factor is low, and the harmonics have a relatively large pollution to the power grid.

Summary of the invention

In view of this, the present invention provides an LED lamp that can effectively dissipate heat and directly connect to the mains.

In order to achieve the above objectives, the following technical solutions are adopted:

An AC-driven fin-type heat-dissipating LED lamp comprises a lamp cover, a lamp body, a lens, and an adaptive driving circuit for driving the lamp body. The lamp body is disposed in the lamp cover, and the lens is disposed at a lower end of the lamp body, and the lamp cover is evenly distributed The fins are provided with parallel opposite heat dissipation holes, and the lamp body comprises a plurality of LED light strings connected in series, and the lamp body is connected with the adaptive driving circuit, and the adaptive driving circuit is centrally disposed at the central portion of the lampshade above the lens, The adaptive driving circuit comprises: a rectifying unit, a current limiting unit, a voltage detecting and conducting control unit and a plurality of controllable switching units; and a rectifying unit for converting an alternating current input from the alternating current power source into a rectified driving voltage; The conduction control unit is configured to detect a comparison result of the driving voltage and the plurality of reference voltages to control on and off of the plurality of controllable switching units, each reference voltage is associated with a controllable switching unit, and the associated reference voltage is higher than the driving The controllable switching unit of the voltage is disconnected, and the control reference voltage is connected to the at least one controllable switching unit of the driving voltage; the controllable a shut-off unit for controlling the switching of the LED string connected in series to the negative end of the power supply of the rectifying unit; and a current limiting unit for inputting the first LED of the plurality of LED strings connected in series after limiting or driving the driving voltage light post.

Further, a surge protector is included, and the surge protector does not need to be externally connected, and can be combined with the adaptive drive circuit to form an integral circuit structure, which is installed in the lamp cover. The surge protector ensures the stability of the LED light during lightning weather.

Further, a plurality of LED strings connected in series are mounted on an aluminum substrate.

Further, each LED light string includes a plurality of LED light beads in series.

Further, the voltage detecting and conducting control unit further comprises a plurality of reference voltage dividing resistors and a voltage stabilizing source, and the reference voltage dividing resistor divides the voltage outputted by the voltage stabilizing source to obtain a plurality of reference voltages.

Further, the input end of the rectifying unit is connected to the AC voltage, and the output end is connected to the input end of the voltage detecting and conducting control unit, and the connection point of each LED string is grounded through the controllable switching unit, and the output end of the rectifying unit passes the limit The flow unit is connected to the first LED string of the plurality of LED strings connected in series, and the output of the voltage detection and conduction control unit is connected to the control end of the controllable switch unit.

Further, the voltage detecting and conducting control unit comprises a plurality of comparators connected to the controllable switching unit, and the comparator is configured to control the switching of the controllable switching unit connected to the comparator according to the comparison result of the driving voltage and the plurality of reference voltages .

Further, the voltage detecting and conducting control unit comprises a single chip microcomputer, and the analog to digital converter of the single chip microcomputer is connected with the output end of the rectifying unit, detecting the comparison result of the driving voltage and the plurality of reference voltages in real time, and controlling the connection with the output port of the single chip microcomputer. Controllable switching unit on and off.

Further, the lens is a lens made of PMMA material and has high light transmittance.

Further, the light exit angle of the lens ranges from 30 degrees to 120 degrees.

The beneficial effects of the invention:

The AC-driven fin-type heat-dissipating LED lamp has a fin disposed on the lamp cover, and a heat-dissipating hole is arranged on the fin, and the convection air passage which is transparent to the left and right forms a three-dimensional heat dissipation with the fin gap, thereby maximally dissipating heat. There is no need to add a radiator, which reduces the structure of the LED lamp and reduces the cost. And an adaptive driving circuit is provided, and the LED lamp beads connected in series are automatically adapted to the change of the driving voltage by controlling the number of LEDs that are turned on, and the number of LEDs that are turned on when the driving voltage is low is small, and the number of LEDs that are turned on when the driving voltage is high is large. Therefore, the total voltage drop of the LED follows the change of the driving voltage, and the power can be connected to the commercial power through a simple control circuit and a current limiting or constant current circuit, and the LED is normally operated in an extremely simple driving manner, eliminating the complicated constant current. The drive circuit and the electrolytic capacitor with life limit eliminate stroboscopic, improve power factor, reduce harmonic distortion, eliminate electromagnetic interference, and reduce cost.

DRAWINGS

FIG. 1 is a front view of an AC driven fin type heat dissipation LED lamp according to the present invention.

2 is an exploded view of an AC-driven fin-type heat-dissipating LED lamp according to the present invention.

3 is a schematic structural view of a lampshade of an AC-driven fin-type heat-dissipating LED lamp according to the present invention.

4 is a schematic structural view of an aluminum substrate of an AC-driven fin-type heat-dissipating LED lamp according to the present invention.

FIG. 5 is a schematic view showing the lens structure of an AC-driven fin-type heat-dissipating LED lamp according to the present invention.

FIG. 6 is a schematic structural diagram of an adaptive driving circuit of an AC-driven fin-type heat-dissipating LED lamp according to the present invention.

FIG. 7 is a schematic diagram showing changes in conduction and shutdown and driving voltage of the controllable switching unit.

Detailed ways

The content of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 1 and FIG. 2, an AC-driven fin-type heat-dissipating LED lamp includes a lamp cover 10, a lamp body (not shown), a lens 20, and an adaptive driving circuit 30 for driving the lamp body, and the lamp body is disposed. Shade 10, the lens 20 is disposed at the lower end of the lamp body, and the lens 20 and the lamp cover 10 together form a receiving area, and the lamp body and the adaptive driving circuit 30 are disposed in the receiving area.

The lamp cover 10 is screwed to a hook 50 via a connecting plate 40. A surge protector 60 is disposed below the connecting plate 40. The surge protector 60 is located inside the lamp cover 10, and the upper end thereof is connected to the connecting plate 40 by screws. The surge protector 60 can be externally mounted or not integrated, and combined with the adaptive drive circuit 30 to form an integral circuit structure, which is mounted in the lamp cover 10 to make the structure more compact and simple.

As shown in FIG. 3 , a plurality of fins 11 are evenly disposed on the lamp cover 10 , and the fins 11 are respectively provided with heat dissipation holes 111 , and the heat dissipation holes 111 on the opposite fins 11 are parallel and opposite to each other. The convection air passage forms a three-dimensional heat dissipation with the fins 11 to dissipate heat to the utmost extent.

As shown in FIG. 4, the lamp body includes a plurality of LED strings L1, L2, ... Ln including a plurality of series connected, and each LED string includes a plurality of LED lamp beads (not shown) connected in series, the lamp bead They are all mounted in a mounting hole 71 of an aluminum substrate 70. The lens 20 is connected by a screw under the aluminum substrate 70. The lens 20 is made of a high transmittance PMMA material. As shown in FIG. 5, the lens 20 is uniformly provided with a plurality of transparent lenses. The light hole 21 is used for the emission of light, and the angle of illumination of the lens 20 is generally designed to be between 30 degrees and 120 degrees.

The lamp body is operated by being in communication with the adaptive drive circuit 30. The adaptive circuit 30 is centrally disposed at the center of the inside of the globe 10, and the circuit can be driven without external use.

As shown in FIG. 6, the adaptive driving circuit 30 includes a rectifying unit 31, a current limiting unit 32, a voltage detecting and conducting control unit 33, and a plurality of controllable switching units K1, K2, ..., Kn. The rectifying unit 31, that is, a rectifying circuit composed of D1 to D4 in the figure, is for converting an alternating current voltage output from the alternating current power source into a rectified driving voltage. a voltage detecting and conducting control unit 33, configured to control on/off of the controllable switching unit according to a change of a driving voltage, each reference voltage being associated with a controllable switching unit, and controlling the associated reference voltage to be higher than a driving voltage The controllable switching unit is disconnected, and at least one controllable switching unit that controls the associated reference voltage to be lower than the driving voltage is connected. The controllable switch unit is configured to control the switching of the LED string connected in series to the negative end of the power supply of the rectifying unit, wherein K1 controls the LED string L1, K2 controls the LED string L2 ... Kn controls the LED string Ln. The current limiting unit 32 is configured to input a first LED string of the plurality of serially connected LED strings after current limiting or constant current driving, and the current limiting can be realized by a resistor connected in series in the circuit, and the constant current is implemented. It can be realized by a constant current source circuit.

The working principle of the adaptive driving circuit is: the commercial power is rectified by the rectifying unit 31 to become a fluctuating direct current, that is, the alternating current voltage outputted by the alternating current power source is converted into a rectified driving voltage, and the voltage is detected and turned on. The control unit 43 detects the driving voltage change in real time, and drives a part of the controllable switching unit to be turned on when the driving voltage is low, and drives the other part of the controllable switching unit to be turned on when the driving voltage is high; the LED light string is connected in series, and the segments are different from each other. The controllable switch unit connected in the voltage section is connected, so that the number of serially connected LED strings follows the change of the driving voltage, the number of LED strings connected in series when the driving voltage is low is small, and the number of LED strings connected in series when the driving voltage is high is large. When the voltage is low, some LED strings are turned on. When the voltage is high, more LED strings are turned on, so that the total voltage drop of the LED is always close to the driving voltage, so that the LED is not too high and the overcurrent is damaged. At the same time, since the LED string is turned on during the entire mains voltage change cycle, the stroboscopic is eliminated, and the high power factor and low harmonic distortion are maintained, and the power factor can easily reach 0.95. Above, the harmonics can also be less than 20%.

Figure 6, there are L1, L2 ... Ln string LED light string and corresponding K1, K2 ... Kn controllable switch unit, each string of LED light string is made up of several LED lights in series, depending on the mains The size and number of strings depends. The AC mains is rectified by the rectifying unit 31 to become a fluctuating DC drive LED string, the rectified voltage is the driving voltage, the voltage detecting and conducting control unit 33 detects the driving voltage in real time, and the conduction control is performed when the voltage is low. The circuit control K1 is turned on, at this time, it is equivalent to the LED light string L1 (composed of several LED light beads in series, the same below) to conduct light; when the voltage rises, the voltage detecting and conducting control unit 33 controls K1 to turn off, K2 When it is turned on, it is equivalent to the conduction of L1 and L2 in series, and the total voltage drop is also increased after L1 and L2 are connected in series, which can adapt to the change of the driving voltage, so that the LED does not suffer from overcurrent damage due to the driving voltage being too high. It can work normally; therefore, when the driving voltage rises to near the maximum value, Kn is turned on and the rest is turned off. At this time, all the LED strings are connected in series, and the voltage drop reaches the maximum value. When the driving voltage starts to drop, the above process repeats, and the turn-on and turn-off sequences of K1 to Kn are reversed, Kn is turned on first, and K1 is turned on last. The end result is that the voltage drop of the LED string can follow the change in the drive voltage, in conjunction with the current limiting unit 32, thereby allowing the LED to operate normally within the allowable drive voltage and drive current range. FIG. 7 is a schematic diagram showing the on and off of the controllable switch unit and the change of the driving voltage.

The detailed description above is a detailed description of the possible embodiments of the present invention, which is not intended to limit the scope of the invention, and the equivalents and modifications of the present invention should be included in the scope of the patent. in.

Claims

An AC-driven fin-type heat-dissipating LED lamp includes a lamp cover, a lamp body, a lens, and an adaptive driving circuit for driving the lamp body. The lamp body is disposed in the lamp cover, and the lens is disposed at a lower end of the lamp body, and is characterized by: A plurality of fins are evenly disposed on the lamp cover, and the fins are provided with parallel opposite heat dissipation holes, and the lamp body includes a plurality of LED light strings connected in series, and the lamp body is in communication with the adaptive driving circuit. The adaptive driving circuit is centrally disposed at a central portion of the lampshade above the lens, and the adaptive driving circuit includes: a rectifying unit, a current limiting unit, a voltage detecting and conducting control unit, and a plurality of controllable switching units; a unit for converting an AC voltage input by the AC power source into a rectified driving voltage; the voltage detecting and conducting control unit, configured to detect a comparison result of the driving voltage and the plurality of reference voltages, and control the plurality of the controllable switches The switching of the unit, each reference voltage is associated with a controllable switching unit, and the controllable switching unit whose control reference voltage is higher than the driving voltage is disconnected, and the control is turned off. The control voltage is lower than the at least one controllable switch unit of the driving voltage; the controllable switch unit is configured to control the on and off of the series connected LED string to the negative end of the power supply of the rectifying unit; the current limiting unit is configured to The driving voltage is subjected to current limiting or constant current input to the first LED string of the plurality of series connected LED strings.
The AC drive finned heat-dissipating LED lamp of claim 1 further comprising a surge protector, said surge protector being externally coupled to said adaptive drive circuit to form a unitary body The circuit structure is installed in the lamp cover.
The AC driven finned heat-dissipating LED lamp of claim 1 , wherein the plurality of LED strings connected in series are mounted on an aluminum substrate.
The AC driven finned heat-dissipating LED lamp of claim 1 wherein said LED string comprises a plurality of LED bulbs connected in series.
The AC-driven fin-type heat-dissipating LED lamp according to claim 1, wherein the voltage detecting and conducting control unit further comprises a plurality of reference voltage dividing resistors and a voltage stabilizing source, and the reference voltage dividing resistor A plurality of the reference voltages are obtained by dividing a voltage output by the regulated source.
The AC-driven fin-type heat-dissipating LED lamp of claim 1 , wherein an input end of the rectifying unit is connected to an AC voltage, and an output end is connected to an input end of the voltage detecting and conducting control unit, and each The connection point of the LED light string is grounded through the controllable switch unit, and the output end of the rectifier unit is connected to the first LED light string of the plurality of series connected LED light strings through a current limiting unit, the electricity An output of the voltage detection and conduction control unit is coupled to a control terminal of the controllable switching unit.
The AC driven finned heat-dissipating LED lamp according to claim 1, wherein said voltage detecting and conducting control unit comprises a plurality of comparators connected to the controllable switching unit, said comparators for driving voltages The comparison with the plurality of reference voltages controls the switching of the controllable switching unit connected to the comparator.
The AC-driven fin-type heat-dissipating LED lamp according to claim 1, wherein the voltage detecting and conducting control unit comprises a single-chip microcomputer, and the analog-to-digital converter of the single-chip microcomputer is connected to an output end of the rectifying unit, and the real-time detecting is performed. And comparing the driving voltage with the plurality of reference voltages, and controlling the on and off of the controllable switching unit connected to the output port of the single chip microcomputer.
The AC driven finned heat-dissipating LED lamp of claim 1 wherein said lens is a lens made of PMMA material.
The AC driven finned heat-dissipating LED lamp of claim 1 , wherein the lens has an exit angle ranging from 30 degrees to 120 degrees.