CN201152473Y - LED decorative lamp - Google Patents

Abstract

The utility model provides a LED decorative lamp, which comprises a light-emitting diode timing light control circuit connected with an input end of an alternating current power supply and a decorative lamp string formed by connecting at least one light-emitting diode in series, wherein the decorative lamp string and the input end of the alternating current power supply are connected with a first diode for rectifying and filtering; the light-emitting diode timing light control circuit controls the on-off of the power supply of the LED decorative lamp string; the light-emitting diode timing light control circuit comprises an alternating current-direct current power supply conversion unit, a light control switch circuit, a timing circuit and a power supply on-off execution circuit. The utility model discloses not only realized carrying out timing on-off control to LED decorative lamp cluster according to the light and shade of light, but also reached LED decorative lamp cluster illumination status's stable control through mutually supporting of timing chip U1 and photo resistance RG, practiced thrift the electric energy effectively.

Description

A kind of LED decorative lamp

technical field

The utility model relates to a decorative lamp, in particular to an LED lamp decorative lamp which can be controlled at regular intervals during work and can be controlled according to light.

Background technique

Using light-emitting diodes (LEDs) as light sources is an inevitable trend in future lamps and lanterns. The main reason is that light-emitting diodes have many advantages such as low power consumption, low temperature and long working life.

At present, most light-emitting diodes are widely used in landscape lighting and urban lighting projects; however, these landscape lighting and urban lighting require manual control of their switches, and users need to constantly worry about when to turn on and off these lighting devices. Also can forget to turn off or open these lighting facilities, bring some inconvenience to use, but also cause the waste of electric energy.

Utility model content

In order to solve the above problems, the main purpose of this utility model is to provide a LED decorative lamp. When applied, the decorative lamp can realize humanized automatic control such as light-controlled opening and closing of the LED decorative lamp string and timing maintenance of the lighting state. .

In order to achieve the above purpose, the utility model provides a LED decorative lamp, which includes a light-emitting diode timing light control circuit connected to the input end of the AC power supply and a decorative light string composed of at least one light-emitting diode connected in series. The input end of the AC power supply is connected in series with a first diode; the light-emitting diode timing light control circuit controls the on-off of the power supply of the LED decorative light string; the light-emitting diode timing light control circuit includes an AC-DC power conversion unit , a light control switch circuit, a timing circuit, and a power on-off execution circuit; the AC-DC power conversion unit is used to convert the input AC power into a DC stabilized power supply, which includes: a first resistor connected in series with the input terminal of the AC power supply And the second diode, and the voltage regulator tube and the first capacitor connected between the output terminal of the second diode and the ground terminal in parallel with each other; the light control switch circuit includes a first PNP type triode, a fourth NPN type triode, a third resistor, a fourth resistor and a photoresistor; wherein, the emitter of the first triode is connected to the AC-DC power conversion unit, and the base is connected to the fourth and third resistors through the fourth resistor connected to the collector of the transistor, the emitter of the fourth transistor is connected to the ground terminal, and the third resistor is connected in parallel to the emitter of the first transistor and the base of the fourth transistor Between, the photoresistor is connected to the base of the fourth triode and the ground terminal in parallel, the first triode is a PNP type triode, and the fourth triode is an NPN type triode; the timing switch circuit and the light The control switch circuit is connected in series to receive the power loading signal and start the timing module for timing operation, and generate a signal to drive the power on and off of the decorative light string; the power on and off execution circuit includes a first connected to the output terminal of the timing circuit Eight resistors, and a thyristor connected in series between the decorative light string and the ground terminal, the output of the eighth resistor controls the on-off of the thyristor.

It can be seen from the above technical solution that the LED decorative lamp of the present invention has the following beneficial effects:

1) The light control switch circuit uses a photoresistor to generate and control the on and off of the power supply of the LED light string according to the brightness and darkness of the light in the use occasion, which realizes humanized automatic control, is convenient for users to control, and effectively saves electric energy.

2) The light-controlled switch circuit is equipped with a timing switch circuit, which is kept for a certain period of time (for example, eight hours at night) through the timing switch circuit, so that once the power supply of the LED light string is turned on by the light-controlled switch circuit, it will no longer be affected by external light. The influence of light and shade ensures the stable operation of the LED light string.

Description of drawings

Fig. 1 is a schematic circuit diagram of the LED decorative lamp of the present invention.

Detailed ways

The technical scheme of the utility model is further described in detail below in conjunction with the embodiments shown in the accompanying drawings.

Please refer to Fig. 1, Fig. 1 is a schematic circuit diagram of the LED decorative lamp of the present invention. In this embodiment, the power source used by the LED decorative lamp is an AC power source J1, such as 120V AC power. The circuit of the LED decorative lamp includes a light-emitting diode timing light control circuit connected to the input end of the AC power supply J1 and a decorative lamp string 1 composed of at least one light-emitting diode in series.

As shown in the figure, the decorative light string 1 is composed of 49 light-emitting diodes (D2 to D50) connected in series in sequence, and the decorative light string 1 is connected in series with the input end of the AC power source J1 to have a first rectification function. Diode D1; the AC power source J1 is half-wave rectified by the first diode D1 to supply power to the decorative light string 1 .

The light-emitting diode timing light control circuit is composed of an AC-DC power conversion unit 2 , a light control switch circuit 3 , a conduction maintenance circuit 4 , a timing circuit 5 and a power supply on-off execution circuit 6 .

The AC-DC power conversion unit 2 for converting the input AC power into a DC stabilized power supply includes: a first resistor R1 and a second diode D51 connected in series with the input terminal of the AC power supply in sequence, and connected in parallel with each other The Zener diode DZ1 and the first capacitor C1 between the output terminal of the second diode D51 and the ground terminal. The AC-DC power conversion unit 2 converts the AC voltage power supply J1 into a low-voltage direct current (for example, 9V direct current), so as to perform the subsequent conduction and maintenance circuit 4, the timing circuit 5, and the power supply on-off for the light-emitting diode timing light control circuit. Circuit 6 supplies power.

Preferably, the two ends of the first capacitor C1 are connected in parallel to the second resistor R2 for discharging the remaining power in the first capacitor C1 after power off.

The light control switch circuit 3 includes: a first PNP transistor Q1, a fourth NPN transistor Q4, a third resistor R3, a fourth resistor R4 and a photosensitive resistor RG; wherein, the emitter of the first transistor Q1 is connected to the The aforementioned AC-DC power conversion unit 2 is connected, the base is connected to the collector of the fourth triode Q4 through the fourth resistor R4, the emitter of the fourth triode Q4 is connected to the ground terminal, and the The third resistor R3 is connected in parallel between the emitter of the first transistor Q1 and the base of the fourth transistor Q4, and the photosensitive resistor RG is connected in parallel with the base of the fourth transistor Q4 and the ground terminal, the first transistor Q1 is a PNP transistor, and the fourth transistor Q4 is an NPN transistor.

The above circuit structure makes the photosensitive resistor RG and the third resistor R3 form a voltage divider circuit. When the external light is strong (i.e. during the day), the resistance value of the photosensitive resistor RG is small; when the external light is dark (i.e. at night), As the resistance value of the photosensitive resistor RG increases, the voltage loaded on the photosensitive resistor RG will change accordingly; if the voltage value loaded on the photosensitive resistor RG is greater than a certain set value (for example, 0.3V), then the fourth triode Q4 will be turned on, so that the first triode Q1 will be turned on. At this time, the timing circuit 5 connected in series with the light control switch circuit 3 is loaded with the DC power outputted by the AC-DC power conversion unit 2 .

In this implementation, the timing circuit 5 is a timing chip U1, and after the 9th to 14th pins on the timing chip U1 are loaded with a DC power supply (for example, 9V), a signal for driving the power supply of the decorative light string 1 is generated and output. (the 8th pin of the timing chip U1 outputs a high level), so that the whole circuit is in the conduction path state, that is, the decorative lamp string 1 (light emitting diodes D2 to D50) is lit; at the same time, the timing chip U1 first The high level that 8 pins output starts to start its internal timing module to carry out timing operation (for example, timing eight hours), and after eight hours, the output terminal of timing circuit 5 (the 8th pin of timing chip U1) outputs off and loads When the power supply on the decorative lamp string 1 is at a low level, at this moment, the entire circuit is in a disconnected state, and the decorative lamp string 1 (light emitting diodes D2 to D50 ) is extinguished.

It should be noted that the timing circuit 5 also includes a manual timing reset module or an automatic timing reset module, which can complete the timing reset function of the timing circuit 5 .

In order to make the power supply of the LED light string once controlled and turned on by the light control switch circuit, it will no longer be affected by the brightness of the external light, that is, to ensure the stability of the light emitting state of the LED light string, the decorative lamp further includes a conduction maintenance circuit 4 . The conduction holding circuit 4 includes a second capacitor C2, a fifth resistor R5 and a third transistor Q3; the third transistor Q3 is an NPN transistor, and its collector is connected to that of the fourth transistor Q4. The collector is connected, and the emitter is connected to the ground; the second capacitor C2 is connected in parallel between the base of the third transistor Q3 and the ground; one end of the fifth resistor R5 is connected to the third transistor Q3 The base is connected, and the other end is connected with the output end of the timing circuit 5 (the eighth pin of the timing chip U1).

When the output terminal of the timing circuit 5 (the 8th pin of the timing chip U1) is at a high level, the LED light string emits light. At this time, since the base of the third triode Q3 is connected to the 8th pin , is also high level, and the fourth triode Q4 and the third triode Q3 share the collector, therefore, when the photosensitive resistor RG is affected by the external light (for example, it becomes bright again), as long as the Before the timing (for example, eight hours) of the timing circuit 5 arrives, the on-off of the decorative light string 1 cannot be affected.

The power supply on-off command output by the output terminal of the timing circuit 5 is executed by the on-off execution circuit 6, and the on-off execution circuit 6 can be various controlled electronic switches. In this embodiment, the on-off execution circuit 6 specifically includes an eighth resistor R8 connected to the output terminal of the timing circuit 5, and a thyristor Q5 connected in series between the decorative light string 1 and the ground terminal. The output of the eight resistors 8 controls the on-off of the thyristor Q5.

Therefore, the utility model not only realizes the timed opening and closing control of the LEDs D2 to D50 according to the brightness and darkness of the light, but also achieves the stable control of the lighting state through the mutual cooperation of the timing chip U1 and the photoresistor RG, effectively saving electric energy .

The above is only a preferred embodiment of the utility model, and is not intended to limit the utility model in any form. Any person familiar with this technology may use the technical content disclosed above to change or modify it into an equivalent change, etc. Effective embodiments, all the content that does not depart from the technical solution of the utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the utility model still belong to the scope of the technical solution of the utility model.

Claims (4)

1. An LED decorative lamp, comprising a light-emitting diode timing light control circuit connected to an AC power input terminal and a decorative light string (1) composed of at least one light-emitting diode connected in series, the light-emitting diode timing light control circuit controls the LED On and off of the power supply of the decorative light string; it is characterized in that: The decorative light string (1) is connected in series with the AC power input end with a first diode (D1); The light-emitting diode timing light control circuit includes: The AC-DC power conversion unit (2) is used to convert the input AC power into a DC stabilized power supply, which includes: a first resistor (R1) and a second diode (D51) connected in series with the input terminal of the AC power supply in sequence ), and a regulator tube (DZ1) and a first capacitor (C1) connected in parallel between the output terminal of the second diode (D51) and the ground terminal; The light control switch circuit (3) includes: a first PNP transistor (Q1), a fourth NPN transistor (Q4), a third resistor (R3), a fourth resistor (R4) and a photoresistor (RG); wherein, The emitter of the first transistor (Q1) is connected to the AC-DC power conversion unit (2), and the base is connected to the collector of the fourth transistor (Q4) through a fourth resistor (R4). The electrodes are connected, the emitter of the fourth triode (Q4) is connected to the ground terminal, and the third resistor (R3) is connected in parallel with the emitter of the first triode (Q1) and the fourth Between the bases of the transistors (Q4), the photoresistor (RG) is connected in parallel to the base of the fourth transistor (Q4) and the ground terminal, and the first transistor (Q1) is a PNP type transistor, The fourth transistor (Q4) is an NPN transistor; The timing circuit (5) is connected in series with the light control switch circuit (3) to receive the power loading signal and start the timing module for timing operation, and generate a signal to drive the power supply of the decorative light string (1) on and off; The power on-off execution circuit (6) includes an eighth resistor (R8) connected to the output terminal of the timing circuit (5), and a thyristor (Q5) connected in series between the decorative light string (1) and the ground terminal ), the output of the eighth resistor (8) controls the on-off of the thyristor (Q5). 2. The LED decorative lamp according to claim 1, characterized in that: the AC-DC power conversion unit (2) further includes a second resistor (R2) connected in parallel to both ends of the first capacitor (C1) to leak The power remaining in the first capacitor (C1) after the power is turned off. 3. The LED decorative lamp according to claim 1, characterized in that it further comprises a conduction maintaining circuit (4), and the conduction maintaining circuit (4) includes: The third transistor (Q3), the third transistor (Q3) is an NPN transistor, its collector is connected to the collector of the fourth transistor (Q4), and the emitter is connected to the ground terminal; The second capacitor (C2) is connected in parallel between the base of the third triode (Q3) and the ground terminal; A fifth resistor (R5), one end of which is connected to the base of the third transistor (Q3), and the other end is connected to the output end of the timing circuit (5). 4. The LED decorative lamp according to claim 1, wherein the timing circuit (5) further comprises a manual timing reset module or an automatic timing reset module.

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