CN216868260U

CN216868260U - Flexible LED lamp strip

Info

Publication number: CN216868260U
Application number: CN202123152393.2U
Authority: CN
Inventors: 文应武; 赵秀成; 文勇
Original assignee: Zhongshan Mlight Photoelectric Co ltd
Current assignee: Zhongshan Mlight Photoelectric Co ltd
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2022-07-01
Anticipated expiration: 2031-12-15

Abstract

The utility model discloses a flexible LED lamp strip which comprises a flexible circuit board, wherein an LED circuit is printed on the flexible circuit board and comprises a power input positive end and a power input negative end, an LED unit and a constant current unit are sequentially connected in series between the power input positive end and the power input negative end, the LED unit comprises a plurality of LED groups connected in parallel, each LED group comprises a plurality of LED lamp beads connected in series, and the constant current unit comprises a plurality of NPN constant current source sub-circuits connected in parallel. Each LED group and each NPN constant current source sub-circuit work independently, even if welding spots of elements in any one of the LED groups or the NPN constant current source sub-circuits fall off, the LED circuits can still work normally, the reliability is high, and the cost is low; the lamp area also can guarantee that the LED circuit can normally work after shearing partial LED group and NPN constant current source sub-circuit.

Description

Flexible LED lamp strip

Technical Field

The utility model relates to a flexible LED lamp strip.

Background

As shown in fig. 1 and 2, the conventional flexible LED light strip includes a flexible circuit board 1A and a coating layer 2A, an LED circuit is printed on the flexible circuit board, a plurality of LED lamp beads 3A and a plurality of constant current units 4A are welded on the front surface of the flexible circuit board, the plurality of constant current units 4A are arranged at intervals along the length direction of the flexible circuit board 1A, one LED lamp bead 3A is arranged between two adjacent constant current units 4A, that is, one constant current unit 4A is arranged between two adjacent LED lamp beads 3A, each LED lamp bead 3A is connected in series with one constant current unit 4A to form one light source unit, the plurality of LED lamp beads 3A and the plurality of constant current units 4A form a plurality of light source units, the plurality of light source units are connected in parallel, the coating layer 2A extends along the length direction of the flexible circuit board 1A to coat the flexible circuit board 1A, the plurality of LED lamp beads 3A and the plurality of constant current units 4A, the layout of LED lamp pearl and resistance in current flexible LED lamp area can make flexible LED lamp area realize shearing wantonly or slight shearing, namely the user can cut the lamp area according to required length, thereby obtain suitable service length, make the use in flexible LED lamp area more humanized, but because the overall arrangement has an LED lamp pearl between two adjacent constant current units, the overall arrangement has a constant current unit 4A between two adjacent LED lamp pearls 3A promptly, make the constant current unit distribute densely, influence simultaneously and the interval setting of two LED lamp pearls 3A on the limited circuit board unit. The flexibility of the flexible LED lamp strip is added, the constant current unit welding spots are easy to fall off when the flexible LED lamp strip is bent, each LED lamp bead is connected with one constant current unit in series, when the constant current unit falls off, the corresponding light source unit can be caused to be broken, the corresponding LED lamp beads can not normally work, dark areas which are in eye obstruction in the lamp strip are formed, and on the other hand, the circuit structure enables the lamp strip to be high in cost and lack of competitiveness.

SUMMERY OF THE UTILITY MODEL

The utility model provides a flexible LED lamp strip which is used for solving the problems in the prior art.

The technical scheme of the utility model is realized as follows:

the utility model aims to provide a flexible LED lamp strip which comprises a flexible circuit board, wherein an LED circuit is printed on the flexible circuit board, and the flexible LED lamp strip is characterized in that: the LED circuit comprises a power input positive end and a power input negative end, an LED unit and a constant current unit are sequentially connected in series between the power input positive end and the power input negative end, the LED unit comprises a plurality of LED groups connected in parallel, each LED group comprises a plurality of LED lamp beads connected in series, and the constant current unit comprises a plurality of NPN constant current source sub-circuits connected in parallel.

The NPN constant current source sub-circuit comprises a first NPN tube and a second NPN tube, wherein a collector of the first NPN tube is connected with a cathode of the LED unit, a base of the first NPN tube is connected with a collector of the second NPN tube to form a first node, the first node is connected with a positive end of a power input through a first resistor, an emitter of the first NPN tube is connected with a base of the second NPN tube to form a second node, the second node is connected with a negative end of the power input through a second resistor, and an emitter of the second NPN tube is connected with the negative end of the power input.

The NPN constant current source sub-circuits are arranged at intervals along the length direction of the flexible circuit board, and at least one LED group is arranged between every two adjacent NPN constant current source sub-circuits in a layout mode.

The first NPN tube and the second NPN tube of the same NPN constant current source sub-circuit are integrated in a chip.

The LED module further comprises an insulating coating layer, wherein the insulating coating layer extends along the length direction of the flexible circuit board to coat the flexible circuit board, the LED unit and the constant current unit.

The flexible printed circuit board further comprises a strip-shaped lead array, the lead array extends along the length direction of the flexible printed circuit board, the lead array comprises at least two leads and an insulating layer, the leads are arranged side by side at intervals, the two leads are respectively connected with a power input positive end and a power input negative end on the flexible printed circuit board, the flexible printed circuit board and the two leads are coated by the insulating layer, and the flexible printed circuit board and the lead array are coated by the insulating coating layer.

Two electrode pins are led out from the end part of the flexible circuit board, the two electrode pins are respectively connected with the power input positive end and the power input negative end, and the two electrode pins protrude out of the insulating coating layer.

Compared with the prior art, the utility model has the following advantages:

1. the flexible LED lamp strip comprises a flexible circuit board, wherein an LED circuit is printed on the flexible circuit board and comprises a power input positive end and a power input negative end, an LED unit and a constant current unit are sequentially connected between the power input positive end and the power input negative end in series, the LED unit comprises a plurality of LED groups connected in parallel, each LED group comprises a plurality of LED lamp beads connected in series, and the constant current unit comprises a plurality of NPN constant current source sub-circuits connected in parallel. The LED unit is formed by connecting a plurality of LED groups in parallel, even if one LED group has a problem, other LED groups can work normally, the voltage at two ends of the LED unit is stable, the brightness of each LED lamp bead is uniform, and the brightness of the whole flexible LED lamp strip is high; the constant current unit is formed by connecting a plurality of NPN constant current source sub-circuits in parallel, the cost is low, even if the welding spots of elements in any one NPN constant current source sub-circuit fall off, the LED circuit can be ensured to work normally, and the reliability is high.

2. Other advantages of the present invention are described in detail in the examples section.

Drawings

Fig. 1 is a schematic perspective view of a flexible LED strip provided in the prior art;

fig. 2 is a schematic circuit structure diagram of the flexible LED strip provided in fig. 1;

fig. 3 is a circuit diagram of a flexible LED strip provided in the first embodiment;

fig. 4 is a schematic structural diagram of a flexible LED strip;

fig. 5 is a schematic diagram of an equivalent circuit structure of the flexible LED strip;

fig. 6 is a schematic structural view of a preferred flexible LED strip;

fig. 7 is a schematic structural diagram of a flexible LED strip according to a second embodiment of the present invention;

fig. 8 is a schematic cross-sectional view of a flexible LED strip.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

as shown in fig. 3 to 6, the present embodiment provides a flexible LED strip, including flexible circuit board 1, the LED circuit is printed on flexible circuit board 1, and its characterized in that: the LED circuit comprises a power input positive end V + and a power input negative end V-, an LED unit 2 and a constant current unit 3 are sequentially connected in series between the power input positive end V + and the power input negative end V-, the LED unit 2 comprises a plurality of LED groups 21 connected in parallel, each LED group 21 comprises a plurality of LED lamp beads 211 connected in series, and the constant current unit 3 comprises a plurality of NPN constant current source sub-circuits 31 connected in parallel.

In the flexible LED lamp strip, the LED unit 2 is formed by connecting a plurality of LED groups 21 in parallel, even if one LED group 21 has a problem, other LED groups 21 can work normally, the voltage at two ends of the LED unit 2 is stable, the brightness of each LED lamp bead 211 is uniform, and the brightness of the whole flexible LED lamp strip is high; the LED group 21 is formed by connecting a plurality of LED lamp beads 211 in series, so that the brightness of the LED lamp strip is improved; the constant current unit 3 is formed by connecting a plurality of NPN constant current source sub-circuits 31 in parallel, the cost is low, even if the welding spots of any one of the NPN constant current source sub-circuits 31 fall off, the LED circuit can be ensured to work normally, and the reliability is high; the lamp strip can also ensure that the LED circuit can work normally after the part of the LED group 21 and the part of the NPN constant current source sub-circuit 31 are cut.

The number of the LED lamp beads 211 of each LED group 21 is 3-10.

The NPN constant current source sub-circuit 31 includes a first NPN transistor Q1 and a second NPN transistor Q2, a collector of the first NPN transistor Q1 is connected to a cathode of the LED unit 2, a base of the first NPN transistor Q1 is connected to a collector of the second NPN transistor Q2 to form a first node a1, the first node a1 is connected to the power input positive terminal V + via a first resistor R1, an emitter of the first NPN transistor Q1 is connected to a base of the second NPN transistor Q2 to form a second node a2, the second node a2 is connected to the power input negative terminal V-via a second resistor R2, and an emitter of the second NPN transistor Q2 is connected to the power input negative terminal V-. The constant current source sub-circuit 31 composed of two NPN tubes has simple structure and low cost.

As shown in fig. 4, the NPN constant current source sub-circuits 31 are arranged at intervals along the length direction of the flexible circuit board 1, and at least one LED group 21 is arranged between two adjacent NPN constant current source sub-circuits 31. The schematic diagram of the LED circuit at this time is shown in fig. 5, a user can cut the lamp strip according to a required length, and each LED group 21 after cutting can be powered by the adjacent/close NPN constant current source sub-circuit 31, so that each LED group 21 can work normally, and the use is convenient.

The first NPN transistor Q1 and the second NPN transistor Q2 of the same NPN constant current source sub circuit 31 are integrated in one chip 311. The space is saved, meanwhile, the welding is convenient, and the cost is further reduced.

The flexible printed circuit board further comprises an insulating coating layer 4, wherein the insulating coating layer 4 extends along the length direction of the flexible printed circuit board 1 and coats the flexible printed circuit board 1, the LED unit 2 and the constant current unit 3. Insulating coating 4 dustproof and waterproof can effectively protect flexible circuit board 1 and each electronic components, makes the working life in guarantee flexible LED lamp area.

As shown in fig. 6, preferably, two

electrode pins

11 and 12 are led out from the end of the flexible circuit board 1, the two

electrode pins

11 and 12 are respectively connected to the positive power input terminal V + and the negative power input terminal V-, and the two

electrode pins

11 and 12 protrude out of the insulating coating 4. The

electrode pins

11, 12 are for connection to a power supply.

Example two:

the flexible LED strip in this embodiment is similar to the flexible LED strip in the first embodiment, except that:

as shown in fig. 7 and 8, the flexible LED strip further includes an elongated lead array 5, the lead array 5 extends along the length direction of the flexible circuit board 1, the lead array 5 includes at least two leads 51 and an insulating layer 52, which are arranged side by side at intervals, the two leads 51 are respectively connected to the positive power input terminal V + and the negative power input terminal V-on the flexible circuit board 1, the insulating layer 52 covers the flexible circuit board 1 and the two leads 51, and the insulating coating layer 4 covers the flexible circuit board 1 and the lead array 5. The wire 51 adopts the stranded wire, uses the stranded wire to carry out the transmission of electric current, can avoid leading to the burnout of wire 51 because the electric current is too big, makes flexible LED lamp area be applicable to high-voltage circuit.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. Flexible LED lamp area, including flexible circuit board (1), the printing has LED circuit, its characterized in that on flexible circuit board (1): the LED circuit comprises a power input positive end V + and a power input negative end V-, an LED unit (2) and a constant current unit (3) are sequentially connected between the power input positive end V + and the power input negative end V-, the LED unit (2) comprises a plurality of LED groups (21) connected in parallel, each LED group (21) comprises a plurality of LED lamp beads (211) connected in series, and the constant current unit (3) comprises a plurality of NPN constant current source sub-circuits (31) connected in parallel.

2. The flexible LED tape of claim 1, wherein: the NPN constant current source sub-circuit (31) comprises a first NPN tube Q1 and a second NPN tube Q2, a collector of the first NPN tube Q1 is connected with a cathode of the LED unit (2), a base of the first NPN tube Q1 is connected with a collector of the second NPN tube Q2 to form a first node (A1), the first node (A1) is connected with a positive power input end V + through a first resistor R1, an emitter of the first NPN tube Q1 is connected with a base of the second NPN tube Q2 to form a second node (A2), a second node (A2) is connected with a negative power input end V-through a second resistor R2, and an emitter of the second NPN tube Q2 is connected with the negative power input end V-.

3. A flexible LED strip according to claim 2, wherein: the NPN constant current source sub-circuits (31) are arranged at intervals along the length direction of the flexible circuit board (1), and at least one LED group (21) is arranged between every two adjacent NPN constant current source sub-circuits (31).

4. A flexible LED strip according to claim 3, wherein: the first NPN tube Q1 and the second NPN tube Q2 of the same NPN constant current source sub circuit (31) are integrated in a chip (311).

5. A flexible LED strip according to claim 4, wherein: the LED constant current unit also comprises an insulating coating layer (4), wherein the insulating coating layer (4) extends along the length direction of the flexible circuit board (1), and the flexible circuit board (1), the LED unit (2) and the constant current unit (3) are coated by the insulating coating layer (4).

6. A flexible LED strip according to any one of claims 1 to 5, wherein: the flexible printed circuit board is characterized by further comprising a strip-shaped lead array (5), the lead array (5) extends along the length direction of the flexible printed circuit board (1), the lead array (5) comprises at least two leads (51) and an insulating layer (52) which are arranged side by side at intervals, the two leads (51) are respectively connected with a power input positive end V + and a power input negative end V-on the flexible printed circuit board (1), the insulating layer (52) covers the flexible printed circuit board (1) and the two leads (51), and the insulating coating layer (4) covers the flexible printed circuit board (1) and the lead array (5).

7. The flexible LED tape of claim 6, wherein: two electrode pins (11, 12) are led out from the end part of the flexible circuit board (1), the two electrode pins (11, 12) are respectively connected with a power input positive electrode end V + and a power input negative electrode end V-, and the two electrode pins (11, 12) protrude out of the insulating coating layer (4).