A connector with PTC

Abstract

The utility model discloses a kind of connectors with PTC, including shell, terminal seat, terminal and PTC element, VCC terminal and GND terminal are symmetrically distributed in data line terminal two sides, form complete circuit system. By cutting VCC terminal and forming gap, PTC element is embedded into gap and bridging contact end and welding end, overcurrent protection is realized in series in current path, and PCB board and SMT patch process of traditional scheme are saved. Terminal seat is equipped with accommodation cavity and fixes PTC element to optimize space layout, data line terminal welding part is covered with insulating sealant to prevent short circuit, terminal is additionally provided with bending part to enhance the fixity with terminal seat, prevent bending elbow from warping to avoid contact part warping, and contact part is extruded arch structure to improve contact reliability. The design solves the problem that traditional connector has no overcurrent protection and is easy to burn machine, and the process of PTC scheme is complex, reduces material cost by 22%, reduces failure rate by 40%, reduces volume by 15%, improves electromagnetic compatibility and structural stability, and is suitable for equipment requiring power and data interaction.

Description

Technical Field

[0001] This utility model relates to the field of electronic connector technology, and in particular to a connector with built-in PTC. Background Technology

[0002] Traditional AM wire-bonding connectors lack PTC (positive temperature coefficient) protection, making them prone to device burnout under high current conditions. AM connectors with PTCs require first soldering the PCB board, then mounting the PTC onto the PCB, and finally soldering the wires. This solution has three major drawbacks:

[0003] Increased PCB board material costs;

[0004] Additional SMT placement process is required, resulting in low production efficiency;

[0005] Multi-layer welding leads to an increased failure rate.

[0006] To address this issue, a connector with built-in PTC is proposed. Utility Model Content

[0007] To address the aforementioned shortcomings, this invention provides a connector that eliminates the need for a PCB board and directly integrates the PTC into the terminals, thereby reducing costs and improving reliability.

[0008] This utility model provides a connector with integrated PTC, including a housing, a terminal block, terminals, and a PTC element. The housing covers the terminal block; the terminals are fixedly mounted on the terminal block and include a VCC terminal; the PTC element is connected in series between the contact end and the soldering end of the VCC terminal. When the current is too high, the PTC resistance increases sharply, limiting the current flow and achieving overcurrent protection. This technical solution eliminates the use of a PCB board and SMT assembly process in traditional solutions, directly integrating the PTC into the terminal, reducing material costs by ≥22%; reducing the number of solder joints, lowering the failure rate by 40%; and simultaneously solving the problem of traditional connectors lacking overcurrent protection and easily burning out.

[0009] Further describing the aforementioned solution, in addition to the VCC terminal, a data line terminal (responsible for data transmission) and a GND terminal (for grounding and ensuring circuit safety) are added, forming a complete "power supply + data transmission + grounding" circuit system that meets the basic functional requirements of a USB connector. This enables the connector to perform power supply, data transmission, and grounding functions, giving it full practical value as a USB Type-A connector, suitable for various devices that require simultaneous power and data interaction.

[0010] Further describing the aforementioned solution, the terminal block has a receiving cavity, and the PTC element is embedded and installed within this receiving cavity, with its two ends electrically connected to the contact end and soldering end of the VCC terminal, respectively. This embedded design optimizes the spatial layout, reducing the overall volume by 15%; it also prevents the PTC element from becoming loose or making poor contact, improving structural stability and the reliability of the protection function.

[0011] Furthermore, the VCC and GND terminals are symmetrically distributed on both sides of the data line terminals, making the current path symmetrical and balanced, reducing electromagnetic interference (EMI). At the same time, the grounding terminal can quickly conduct stray currents, reduce electromagnetic interference during signal transmission, and improve the stability and accuracy of data transmission; optimize the circuit layout and improve the electromagnetic compatibility (EMC) of the connector.

[0012] More preferably, the soldering area of ​​the data line terminal is covered with an insulating sealant layer to isolate solder dross, wire burrs or conductive contact between adjacent terminals that may be generated during the soldering process, forming a physical insulation barrier.

[0013] Furthermore, a bent portion is provided between the contact end and the welding end of the terminal. This bent portion is fitted and fixed inside the terminal holder, increasing the contact area and friction between the terminal and the terminal holder through a mechanical structure, thus restricting the degree of freedom of terminal displacement. This effectively prevents the terminal from loosening or falling off due to insertion / removal force or vibration, enhancing the overall structural stability; extending the connector's service life; and reducing contact failures caused by terminal displacement.

[0014] Further description of the aforementioned solution: the terminal is provided with an anti-bending bend at one end near the contact portion to prevent the contact portion from bending due to frequent insertion and removal, ensuring stable contact with the mating connector and reducing current and signal interruption problems caused by poor contact.

[0015] Further describing the aforementioned solution, the contact portion of the terminal is an extruded arched structure, which can compensate for assembly errors through slight deformation when mating with the connector, ensuring a tight fit between the contact surfaces, improving contact reliability, reducing increased resistance or signal loss due to contact gaps, ensuring the stability of current and data transmission, and reducing transmission loss.

[0016] Further description of the aforementioned solution: the PTC element is embedded and installed by cutting a notch formed by the VCC terminal, and the terminal structures on both sides of the notch are bridged, eliminating the need for additional wires or pad connections, so that the PTC becomes part of the VCC current path.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] Cost reduction: Eliminating PCB boards and SMT processes results in a material cost reduction of ≥22%;

[0019] Improved reliability: Direct connection between PTC and terminals reduces solder joints, resulting in a 40% decrease in failure rate;

[0020] Space optimization: The embedded cavity design reduces the volume by 15%;

[0021] Short circuit protection: The data cable terminals are sealed with adhesive to eliminate the risk of short circuits caused by soldering. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is an overall schematic diagram of an embodiment of the present utility model;

[0024] Figure 2 , 3 An exploded view diagram provided for an embodiment of this utility model;

[0025] Figure 4 A schematic diagram of the terminal structure provided for an embodiment of this utility model;

[0026] Figure 5 This is a schematic diagram of the terminal block and terminal mounting structure provided in an embodiment of the present utility model;

[0027] Figure 6 An exploded view diagram provided for an embodiment of this utility model.

[0028] The following are the labeling elements in the figure:

[0029] 1. Housing; 2. Terminal block; 21. Receiving cavity; 3. Terminal; 31. VCC terminal; 32. Data cable terminal; 33. GND terminal; 34. Bending part; 35. Elbow; 36. Contact part; 4. PTC element.

[0030] The accompanying drawings have illustrated specific embodiments of the present invention, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0032] To make the technical solution and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0033] This utility model will be fully demonstrated through the description of specific structural details and assembly relationships. As shown in Figures 1 to 6, this connector with integrated PTC takes the USB Type-A interface as a typical embodiment. Its core innovation lies in the fact that through structural integration design, the PCB transition layer in the traditional solution is eliminated, and the PTC component 4 is directly embedded in the cut notch of the VCC terminal 31 to form an integrated overcurrent protection path.

[0034] The outer casing 1 is made of flame-retardant alloy, with a hollow internal structure completely enclosing the terminal block 2. The terminal block 2 is made of high-temperature resistant nylon, with multiple positioning grooves and receiving cavities 21 on its surface. The terminal block 3 group includes a VCC terminal 31, a pair of data line terminals 32 (D+ / D-) for data transmission, and a GND terminal 33 for grounding. All are made of highly conductive phosphor bronze with a nickel-plated base and a gold-plated surface. The VCC terminal 31 and GND terminal 33 are symmetrically distributed on both sides of the data line terminal 32, forming a symmetrical and balanced double-grounding structure that significantly reduces electromagnetic interference. The PTC element 4 is a positive temperature coefficient thermistor with a Curie temperature of 120℃ and a rated operating current of 3A, with dimensions controlled at 1.0×2.0×0.5mm. It is directly bridged between the contact end and the solder end of the VCC terminal 31 by laser welding.

[0035] The structural innovation of terminal group 3 is concentrated in four aspects. First, a rectangular notch is punched and cut between the contact end and the welding end of VCC terminal 31. After the PTC element 4 is embedded, it is fixed by pulsed laser welding, so that the current flows along the path of "contact end → PTC element 4 → welding end". When the current exceeds 3A, the resistance value of PTC element 4 jumps a thousand times within 5ms, cutting off the circuit. After the fault is eliminated, it automatically resets. Second, a bent part 34 is punched in the middle of terminal 3. After the bent part 34 is embedded in the trapezoidal slot of terminal seat 2, it forms an interference fit. After 1000 insertion and removal tests, the displacement is verified to be less than 0.1mm, realizing three-dimensional spatial locking. Third, an L-shaped anti-warping elbow 35 is added to the front end of the contact part 36 of terminal 3. When the plug is inserted, it abuts against the inner wall of the outer shell 1 to generate a reverse support torque, so that the warping deformation after 500 insertion and removal is controlled within 0.05mm. Fourth, the 32 soldering ends of the data cable are wrapped with a 0.2mm thick epoxy resin sealant layer to completely isolate the risk of short circuit caused by solder splashes or wire burrs.

[0036] As shown in Figures 5 and 6, the accommodating cavity 21 is located in the middle of the terminal block 2. After the PTC element 4 is embedded, its bottom surface is tightly fitted with the conductive channel. The GND terminal 33 and VCC terminal 31 are respectively placed on both sides of the data line terminal 32, forming a mirrored current loop. Actual measurements show that this layout reduces the area of ​​the VCC31 current loop by 62% and reduces radiated noise by 15 dBμV / m. At the same time, the GND terminal 33 is adjacent to the data line terminal 32, which can instantly conduct away high-frequency interference signals, reducing the data transmission error rate to 10⁻. 9 The magnitude is not specified. To further suppress crosstalk, data line terminal 32 adopts a differential pair twisted design.

[0037] During assembly, terminal 3 is prepared first: phosphor bronze strip is continuously stamped to form the bent part 34 and elbow 35, and the welding end is tin-plated to improve the reliability of the solder wire. The welding end of data line terminal 32 is coated with epoxy resin at the dispensing station, and a uniform insulating layer is formed after curing with hot air at 80℃. Next, PTC element 4 is integrated: PTC element 4 is precisely placed in the notch of VCC terminal 31, the diameter of the pulsed laser solder joint is controlled at 0.3mm, and the post-soldering continuity resistance detection threshold is set to 10mΩ. Then, terminal block 2 is assembled, and the outer shell 1 is encapsulated: the entire assembly is placed into the mold cavity and pressed to form a mold.

[0038] Material costs decreased from RMB 0.85 / piece to RMB 0.66, a reduction of 22.4%; due to the elimination of the SMT placement process, the assembly time per unit was shortened by 12 seconds; the number of solder joints was reduced from 8 to 4, and the defect rate decreased from 35PPM to 21PPM. Overcurrent protection response time was improved from 20ms to 5ms, and the operating temperature range was expanded to -40~105℃. In 5A fast-acting tests, when the output terminal was short-circuited, PTC element 4 cut off the current within 8ms, and the mobile phone charging IC had a 100% integrity rate. Industrial vibration tests showed that under 20G acceleration vibration, the displacement of terminal 3 was less than 5μm, and signal transmission was uninterrupted.

[0039] Alternative implementation schemes are also covered within the scope of this utility model. The PTC element 4 can be fixed using a pre-set solder pad reflow soldering process, which, although increasing the cost by 0.03 yuan, is suitable for automated mass production; the insulating sealant can be replaced with heat-shrink tubing, which heat-shrinks and wraps the welded area after the wires are soldered; the angle of the bending part 34 can be adjusted to any value between 120° and 150°, adapting to different locking force requirements by changing the slot tilt angle. All such modified designs, as long as they conform to the core concept of the PTC element 4 direct-connection terminal 3, fall within the scope of protection of the claims of this utility model.

[0040] This utility model, through the above-described specific embodiments, creatively resolves the contradiction between the lack of overcurrent protection in traditional connectors and the complex process of designs with PTC components. Those skilled in the art can adjust material specifications, dimensional parameters, and process details without departing from the design intent; such equivalent substitutions all fall within the scope of patent protection.

[0041] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the foregoing claims.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element. Conversely, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation. The terms "upper end," "lower end," "left side," "right side," "front end," "rear end," and similar expressions used herein refer to the positional relationship with reference to the accompanying drawings.

[0043] It should be understood that this invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this invention is limited only by the appended claims.

Claims

1. A connector with a built-in PTC, characterized in that: It includes a housing (1), a terminal block (2), a terminal (3), and a PTC element (4); the housing (1) covers the terminal block (2); the terminal (3) is fixedly mounted on the terminal block (2) and includes a VCC terminal (31); the PTC element (4) is connected in series between the contact end and the solder end of the VCC terminal (31).

2. The connector with integrated PTC according to claim 1, characterized in that: The terminal (3) also includes at least one pair of data line terminals (32) and at least one GND terminal (33).

3. The connector with integrated PTC according to claim 1, characterized in that: The terminal block (2) has a receiving cavity (21), and the PTC element (4) is embedded in the receiving cavity (21), with its two ends electrically connected to the contact end and welding end of the VCC terminal (31) respectively.

4. A connector with a built-in PTC according to claim 2, characterized in that: The VCC terminal (31) and GND terminal (33) are symmetrically distributed on both sides of the data line terminal (32).

5. A connector with a built-in PTC according to claim 2, characterized in that: The solder joint of the data line terminal (32) is covered with an insulating sealant layer.

6. A connector with a built-in PTC according to claim 1, characterized in that: The terminal (3) has a bent portion (34) between the contact end and the welding end, and the bent portion (34) is fitted and fixed inside the terminal base (2).

7. A connector with a built-in PTC according to claim 1, characterized in that: The terminal (3) has an anti-bending bend (35) at one end near the contact portion.

8. A connector with integrated PTC according to claim 1, characterized in that: The contact portion (36) of the terminal (3) is an extruded arched structure.

9. A connector with a built-in PTC according to claim 1, characterized in that: The PTC element (4) is embedded and installed through a notch formed by cutting the VCC terminal (31), and the terminal (3) structure on both sides of the notch is bridged.

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