A two-wire plug for a light string
By integrating the control circuit inside the light string plug and using an MCU to control the metal terminals to form a waterproof and sealed structure, the problems of complex structure and high cost of traditional light string plugs are solved, realizing the miniaturization and intelligence of light string plugs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANG ZHOU TING SHEN ELECTRIC
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-12
AI Technical Summary
The traditional split structure of the light string plug and control box increases the number of parts and manufacturing costs. The structure is complex and prone to poor contact. It cannot be equipped with an MCU, which limits the intelligence of the light string and its application scenarios.
The control circuit is integrated inside the plug housing, the metal terminals are controlled by an MCU, and a waterproof and sealed structure is formed by ultrasonic welding, which simplifies the structure and expands the functionality.
It achieves miniaturization, low cost, good waterproof performance, and expandable functions for light string plugs, thereby improving the intelligence and application adaptability of light strings.
Smart Images
Figure CN122202995A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lighting decoration technology, specifically to a two-wire plug for light strings. Background Technology
[0002] Traditional string light products (such as decorative LED string lights) typically consist of three parts: a plug, a control box, and the string itself. The plug is only used to connect to mains power, while the control box is independently located between the plug and the string, housing a control chip or circuitry to achieve effects such as flashing and gradation. This split structure has significant drawbacks: First, the independent control box increases the number of parts and assembly steps, resulting in a higher overall manufacturing cost for the light string. Second, the plug and control box need to be connected by additional wires and connectors, which not only makes the structure complex and bulky, but also easily leads to problems such as poor contact or waterproof failure. Furthermore, the internal space of traditional plugs cannot accommodate circuit boards with control chips (such as MCUs), resulting in plugs with limited functionality and an inability to flexibly expand external components (such as switches), thus limiting the application scenarios and intelligence level of the light string.
[0003] Therefore, there is an urgent need to provide a string light connector that is compact, cost-controllable, and can be equipped with an integrated MCU. Summary of the Invention
[0004] One of the technical problems to be solved by this invention is to provide a two-wire plug for light strings with good waterproof performance; the control circuit is integrated inside the plug housing, and the MCU is used to realize the multi-functional output and expansion of the metal terminals, thereby reducing system cost, simplifying the structure and improving the flexibility of light string applications.
[0005] The second technical problem to be solved by this invention is to provide a two-wire plug for light strings with good waterproof performance.
[0006] To solve one of the aforementioned technical problems, the technical solution of the present invention is: a two-wire plug for a light string, comprising a housing, a metal insert, a circuit board, and a fuse. The housing includes a front part, a middle part, and a rear part. The metal insert is fixed to the front part of the housing. The bottom of the front part of the housing has two receiving slots for accommodating the fuse. The metal insert is connected to the input terminal of the circuit board through the fuse. The circuit board is disposed in the receiving space in the middle part of the housing. The functional circuit on the circuit board includes an MCU chip. The rear part of the housing has two voltage output ports. The voltage output ports have metal terminals connected to the output terminals of the circuit board. The metal terminals are connected to the MCU chip, and the light string is electrically connected to the metal terminals. The housing includes a base and a cover plate. The cover plate is ultrasonically welded to the base to form the receiving space. The cover plate has openings at the solder joints corresponding to the input and output terminals of the circuit board, and the openings are filled with sealant.
[0007] As an improvement, the two-wire plug of the light string also includes a housing that encloses the casing, and the housing has an access window with a push plate corresponding to the fuse location. This structure allows users to replace the fuse without disassembling the entire unit, improving maintenance convenience.
[0008] As an improvement, the front end of the circuit board extends into the limiting groove at the front of the housing, and the rear section of the circuit board is provided with several clearance grooves. These clearance grooves cooperate with the limiting plate at the rear of the housing, and adjacent clearance grooves form a connecting part. The metal terminals are spot-welded to the connecting part. This structure can limit the circuit board in multiple directions to prevent it from loosening during use, while providing a stable welding platform for the metal terminals.
[0009] As an improvement, the light string is connected to the metal terminal at the voltage output port via a wire, and the external component is connected to the metal terminal via the light string wire.
[0010] As an improvement, the external component is a switch.
[0011] As an improvement, the control of the light string is achieved by writing a program into the MCU chip and using an external component.
[0012] To address the second problem of the prior art, the technical solution of this invention is: a two-wire plug for a light string, comprising a housing, a metal insert, a circuit board, and a fuse. The housing includes a front part, a middle part, and a rear part. The metal insert is fixed to the front part of the housing. The bottom of the front part of the housing has two receiving slots for accommodating the fuse. The metal insert is connected to the input terminal of the circuit board through the fuse. The circuit board is located in the receiving space in the middle part of the housing. The rear part of the housing has two voltage output ports, each containing a metal terminal connected to the output terminal of the circuit board. The light string is electrically connected to the metal terminal. The housing includes a base and a cover plate. The cover plate is ultrasonically welded to the base to form the receiving space. The cover plate has openings at the solder joints corresponding to the input and output terminals of the circuit board, and the openings are filled with sealant. The plug interface is surrounded by an annular retaining wall.
[0013] The beneficial effects of this invention compared to the prior art are: 1. High integration: The circuit board with MCU, fuse and metal terminals are all integrated into the plug housing, and the layout is optimized, the size of the plug is reduced, the independent control box is eliminated, and the manufacturing cost and assembly complexity of the light string system are greatly reduced. 2. Expandable functions: The MCU is used to intelligently control the metal terminals, so that the voltage output port can only output the working voltage of the light string, and can also be used as a switch. Users or manufacturers can flexibly configure the light string functions according to actual needs. 3. Programming flexibility: By writing different programs to the MCU, the same hardware platform can adapt to a variety of control logics, significantly improving the application scenario adaptability of the light string; 4. Fill the opening of the cover plate and the socket formed by the retaining wall with sealant to improve the waterproof performance of the plug shell and circuit board. Attached Figure Description
[0014] Figure 1 This is a schematic diagram showing the separation of the outer shell and the core.
[0015] Figure 2 This is a schematic diagram showing the separation of the base and the cover plate.
[0016] Figure 3 This is a schematic diagram showing the connection between the plug, the light string, and the switch.
[0017] Figure 4 This is the first type of functional circuit diagram without a switch.
[0018] Figure 5 This is the functional circuit diagram for the first type of switch.
[0019] Figure 6 This is the second type of functional circuit diagram without a switch.
[0020] Figure 7 This is the functional circuit diagram for the second type of switch. Detailed Implementation
[0021] The present invention will now be further described with reference to the accompanying drawings.
[0022] like Figure 1 , 2 As shown, a two-wire plug for a light string includes a housing and a core inserted into the housing. The core includes a housing 1, metal prongs 2, a circuit board 3, and a fuse 4. The housing 1 is made of flame-retardant plastic and is integrally formed from a front part 11, a middle part 12, and a rear part 13. The metal prongs 2 are two standard power pins, fixed in slots in the front part 11 of the housing, for insertion into a mains power socket. The housing 5 is made of hard plastic and has an access window 51 corresponding to the position of the fuse 4. A sliding or flip-up push plate 52 is installed on the window. When the fuse needs to be replaced, simply push open the push plate 52, remove the old fuse with a tool, and insert the new fuse; there is no need to disassemble the housing.
[0023] like Figure 1 As shown, two receiving slots 111 are formed at the bottom of the front part 11 of the housing, and each receiving slot 111 contains a fuse 4. The tail end of the metal insert 2 is electrically connected to one end of the fuse 4 through a conductive spring, and the other end of the fuse 4 is connected to the input terminal of the circuit board 3 through a wire or direct contact. In this way, when the current is too large, the fuse blows, protecting the subsequent circuit and the light string.
[0024] like Figure 2As shown, the central part 12 of the housing is a hollow accommodating space 121, within which the circuit board 3 is horizontally mounted. The circuit board 3 is equipped with a rectifier filter circuit, a step-down circuit, and an MCU chip 31. In this embodiment, the hollow accommodating space 121 is approximately rectangular, and the circuit board 3 has a similar shape. Larger electronic components are located on the back of the circuit board 3 and placed within the accommodating space 121, while smaller electronic components are located on the front of the circuit board 3, resulting in a compact and simple overall structure.
[0025] The rear part 13 of the housing has two voltage output ports 131, and each voltage output port 131 has a metal terminal 132 fixed inside. The metal terminal 132 is connected to the I / O port or power output terminal of the MCU chip 31 through printed circuits on the circuit board 3. Figure 3 As shown, the light string is connected to metal terminal 132 via wires. The wires have pins at their ends, which, after being inserted into voltage output port 131, engage with the metal terminal to form an electrical connection. An external component, such as a switch, can be connected to the light string's wires for expansion. The MCU chip 31 has a pre-programmed sequence that can change the state of the light string based on signals from the external component.
[0026] For ease of production and assembly, the housing 1 adopts a split structure, including a base and a cover plate 14. The cover plate 14 is sealed and fixed to the base by ultrasonic welding to form the aforementioned accommodating space 121. Openings 141 are respectively provided on the cover plate 14 at the input solder joint 34 and the output solder joint 35 of the circuit board 3. After welding is completed, epoxy resin sealant is injected into the openings 141, and after curing, a waterproof sealing layer is formed. The plug interface 131 is surrounded by an annular baffle. The shape of the plug interface 131 can be square, circular, or other shapes. The plug interface 131 communicates with the accommodating space 121, and the sealant can be poured into the plug interface 131 from the back of the housing. The baffle prevents the sealant from overflowing, thereby improving the overall sealing performance.
[0027] To enhance the positioning reliability of the circuit board 3, a limiting groove 112 is provided inside the front part 11 of the housing, into which the front end of the circuit board 3 is inserted. Multiple limiting plates 133 are provided inside the rear part 13 of the housing, and several clearance grooves 32 are formed at the rear end of the circuit board 3. The clearance grooves 32 are engaged with the limiting plates 133, and the protruding portions between adjacent clearance grooves constitute the connecting portions 33. Metal terminals 132 are directly soldered to the copper foil of the connecting portions 33 using a spot welding machine. This structure avoids the use of additional wires and reduces contact resistance.
[0028] The functional circuits on the circuit board can be configured according to different light strings. For example... Figure 4 As shown, the first functional circuit: AC input, directly driving MCU chip U1, the MCU has a program written inside to correspond to different changes; such as Figure 5As shown, after adding switch S1 to the circuit, switch S1 sends a control signal to the MCU, and the MCU switches between different functions according to its internal program. Figure 6 As shown, the second functional circuit: AC input, AC to DC via rectifier bridge DB1, then powering MCU chip U1 via Zener diode ZD1. The MCU has an internal program that corresponds to different changes; such as... Figure 7 As shown, after adding switch S1 to the circuit, switch S1 sends a control signal to the MCU, and the MCU switches different functions according to its internal program.
Claims
1. A two-wire plug for a light string, comprising a housing, metal contacts, a circuit board, and a fuse, characterized in that: The housing includes a front, middle, and rear section. A metal insert is fixed to the front section of the housing. Two receiving slots for accommodating fuses are located at the bottom of the front section. The metal insert is connected to the input terminal of the circuit board via the fuses. The circuit board is located within the receiving space in the middle section of the housing. The functional circuitry on the circuit board includes an MCU chip. Two voltage output ports are located at the rear section of the housing. Each voltage output port contains a metal terminal connected to the output terminal of the circuit board. The metal terminal is connected to the MCU chip, and the LED string is electrically connected to the metal terminal. The housing includes a base and a cover plate. The cover plate is ultrasonically welded to the base to form the receiving space. Openings are provided on the cover plate at the solder joints corresponding to the input and output terminals of the circuit board, and these openings are filled with sealant.
2. The two-wire plug for a light string according to claim 1, characterized in that: It also includes an outer shell that encloses the housing, and the outer shell has an inspection window with a push plate at the location corresponding to the fuse.
3. A two-wire plug for a light string according to claim 1, characterized in that: The front end of the circuit board extends into the limiting groove at the front of the housing. The rear section of the circuit board is provided with several clearance grooves. The clearance grooves cooperate with the limiting plate at the rear of the housing, and a connecting part is formed between adjacent clearance grooves. The metal terminals are spot-welded to the connecting part.
4. A two-wire plug for a light string according to claim 1, characterized in that: The light string is connected to the metal terminal at the voltage output port via a wire, and the external component is connected to the metal terminal via the light string's wire.
5. A two-wire plug for a light string according to claim 4, characterized in that: The external component is a switch.
6. A two-wire plug for a light string according to claim 4, characterized in that: The control of the light string is achieved by writing a program into the MCU chip and using external components.
7. A two-wire plug for a light string according to claim 4, characterized in that: The wire is electrically connected to the metal terminal by a pin.
8. A two-wire plug for a light string, comprising a housing, metal contacts, a circuit board, and a fuse, characterized in that: The housing includes a front, middle, and rear section. The metal insert is fixed to the front section of the housing. The bottom of the front section of the housing has two receiving slots for accommodating fuses. The metal insert is connected to the input terminal of the circuit board through the fuses. The circuit board is located in the receiving space in the middle section of the housing. The rear section of the housing has two voltage output ports, each containing a metal terminal connected to the output terminal of the circuit board. The lamp string is electrically connected to the metal terminal. The housing includes a base and a cover plate. The cover plate is ultrasonically welded to the base to form the receiving space. The cover plate has openings at the solder joints corresponding to the input and output terminals of the circuit board, and the openings are filled with sealant. The insertion interface is surrounded by an annular retaining wall.