A locking structure of a direct insertion printed board connector

Abstract

The application discloses a locking structure of a direct insertion printed board type connector and belongs to the technical field of printed board installation. The locking structure simultaneously realizes the functions of independently fixing a printed board and independently locking a butt joint end, and solves the problem that when a direct insertion printed board type connector is used as a free end of a flexible printed board, the connector cannot be independently mechanically fixed, thereby causing a soldering point stress problem. The locking structure is provided with support bosses (11) on both sides of a shell (1), printed boards (2) are fixed on the support bosses (11) through sleeve screws (3), and locking screws (4) pass through through holes in the centers of the sleeve screws (3) and are matched with butt joint connectors (7). The locking screws pass through inner holes of the sleeve screws and pass through the shell to be matched and locked with the butt joint end. The locking structure does not change the appearance of a standard series connector, keeps the type spectrum consistent, and has high universality and high adaptability.

Description

Technical Field

[0001] This invention relates to a locking structure for a through-hole printed circuit board connector, belonging to the field of printed circuit board mounting technology. Background Technology

[0002] With the development of technologies in aerospace and other fields, flexible printed circuit board (PCB) cables (hereinafter referred to as PCB cables) are widely used in electrical interconnection. PCB connector fixed-end locking assemblies can directly lock the PCB, and the locking operation can be performed before PCB electrical assembly soldering. After the connector and PCB are soldered, the fixed-end locking assembly does not need to be disassembled, so there is no stress on the solder joints between the connector and the PCB. However, when PCB cable connectors are used as free ends, the traditional free-end locking assembly locks the PCB by having a locking screw pass through the PCB and connector housing, locking the mating end to simultaneously fix the PCB and connector. This means that the tightening operation of the traditional free-end locking assembly can only be performed during final assembly. This results in a situation where components are soldered before being fixed, which may lead to stress on the solder joints due to mismatched tightening torque during final assembly, posing a risk of solder joint failure. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a locking structure for a through-hole printed circuit board connector.

[0004] This invention is achieved through the following technical solution: A locking structure for a through-hole printed circuit board connector includes a printed circuit board 2 and a connector housing 1. Support bosses 11 are provided on both sides of the housing 1. The printed circuit board 2 is fixed to the support bosses 11 on both sides by sleeve screws 3. Locking screws 4 pass through the through hole in the center of the sleeve screws 3 and cooperate with the mating connector 7.

[0005] The support boss 11 has a large-diameter internal threaded hole 12, and the sleeve screw 3 passes through the through hole on the flexible printed circuit board 2 and engages with the large-diameter internal threaded hole 12.

[0006] The outer wall of the sleeve screw 3 has a large-diameter external thread 31, the upper half of the inner wall of the through hole has a small-diameter internal thread 32, and the lower half of the through hole has a smooth structure.

[0007] The locking screw 4 has a small-diameter external thread 41 at its front end. The section from the thread to the nut retains a long, smooth round rod. The specifications of the small-diameter external thread 41 match the small-diameter internal thread 32 of the sleeve screw 3.

[0008] The mating structure of the mating connector 7 has a mating end internal threaded hole 71, and the small-diameter external thread 41 at the front end of the locking screw 4 mates with the mating end internal threaded hole 71.

[0009] The top of the sleeve screw 3 has an external hexagonal structure 33, and a flat washer 5 is provided between the external hexagonal structure 33 and the printed circuit board 2.

[0010] A spring washer 6 is provided between the locking screw 4 and the external hexagonal structure 33. A locking structure for a through-hole printed circuit board connector includes a housing, a sleeve screw, a locking screw, a flat washer, and a spring washer.

[0011] The beneficial effects of this invention are as follows: by using sleeve screws and locking screws, when using a through-hole printed circuit board connector as the free end of a flexible printed circuit board, the mechanical fixing and mating locking of the printed circuit board are independent, so that the mechanical fixing of the printed circuit board can be performed before electrical assembly soldering, and the fastening state will not be changed after soldering, thus avoiding stress on the solder joint. At the same time, this structure does not change the standard connector hole spacing and type, and has high adaptability and versatility. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of the present invention before assembly (showing the structural composition).

[0013] Figure 2 This is a schematic diagram of the docking and assembly structure of the present invention (showing the docking fit).

[0014] Figure 3 These are the front view and sectional view of the modified outer shell of the present invention.

[0015] Figure 4 These are the front view and sectional view of the sleeve screw of the present invention.

[0016] Figure 5 This is a front view of the locking screw of the present invention.

[0017] Figure 6 This is a schematic diagram of the structure after the assembly of the present invention is completed.

[0018] In the diagram: 1-Housing, 2-Printed circuit board, 3-Socket screw, 4-Locking screw, 5-Flat washer, 6-Spring washer, 7-Mating connector 11-Support boss, 12-Large diameter internal thread, 31-Large diameter external thread, 32-Small diameter internal thread, 33-External hexagonal head, 41-Small diameter external thread, 42-Long smooth round rod, 71-Internal threaded hole at mating end.

[0019] Figure 2 middle: a - Loose length of the locking screw; b - Effective screwing depth of the internal threaded hole at the mating end. Detailed Implementation

[0020] Example 1: A locking structure for a through-hole printed circuit board connector includes a housing 1, a printed circuit board 2, sleeve screws 3, and locking screws 4. Support bosses 11 are provided on both sides of the housing 1. The printed circuit board 2 is fixed to the support bosses 11 on both sides by sleeve screws 3. The locking screws 4 pass through the through hole in the center of the sleeve screws 3 and engage with the mating connector 7. That is, the printed circuit board 2 is fixed to the support bosses 11 of the housing 1 by the locking screws 4, and then the housing 1 and the mating connector 7 are fixed together by the locking screws 4.

[0021] Housing 1 is a modified version of the standard series connector housing, mainly featuring a printed circuit board support boss 11 and a large-diameter mounting hole. The printed circuit board support boss 11 is the main stress-bearing surface of the printed circuit board 2 when it is fixed to the connector. The height of the support boss 11 is consistent with the height of the standard connector support sleeve, enlarging the contact surface between the support boss and the printed circuit board to distribute pressure when the printed circuit board 2 is fixed to the connector. A large-diameter mounting hole is located at the center of the boss. The large-diameter mounting hole is designed with an internal thread structure, which mates with the external thread of the sleeve screw 3. The spacing between the mounting holes is consistent with the hole spacing of the standard connector of the same specification, ensuring high versatility and adaptability.

[0022] The sleeve screw 3 is an external hexagonal screw structure with a small-diameter internal thread and a large-diameter external thread. The external thread mates with the mounting hole of the outer shell. After locking by the external hexagonal engagement, the printed circuit board is clamped and fixed. The internal thread is adapted to the external thread of the locking screw 4.

[0023] The locking screw 4 is a small-diameter long-rod screw structure. The screw shank is designed with a thread on the head, which is adapted to the standard specifications of the mating end and the internal thread of the sleeve screw 3. The non-threaded section of the screw shank is a long, smooth round rod. The screw head thread is screwed into and passes through the small-diameter internal thread of the sleeve screw to prevent the screw from falling out. The screw passes through the outer shell and the mating end for fixation, thus achieving mating and locking.

[0024] Flat washers 5 are compatible with sleeve screw specifications to prevent the printed circuit board from being directly subjected to the turning force when the sleeve screw is tightened.

[0025] Spring washer 6 is used to lock the screw and the mating end, increasing the axial force of the screw after tightening to prevent loosening.

[0026] Example 2: like Figures 1 to 4 As shown, the modified housing 1 is based on the standard connector housing with the addition of a support boss 11. The height of the support boss 11 is consistent with the height of the support sleeve of the standard printed circuit board connector to ensure structural compatibility. The contact plane between the boss and the printed circuit board is enlarged to effectively disperse the positive clamping force when the printed circuit board is fixed, while also meeting the opening space of the large-diameter internal thread hole 12. The thread of the large-diameter internal thread hole 12 is tapped from the tail end of the connector to the mating end face, and the thread depth should be in the range of 3 / 5 to 4 / 5 of the through hole length.

[0027] The socket screw 3 features a large-diameter external thread 31, a small-diameter internal threaded hole 32, and an external hexagonal head 33. The large-diameter external thread 31 matches the specifications of the large-diameter internal threaded hole 12 in the outer casing 1. The thread taps from the screw head towards the external hexagonal head 33, and the thread length is 0.5–1 mm shorter than the length of the large-diameter internal threaded hole 12. The central axis of the socket screw has a small-diameter internal threaded hole 32, the specifications of which are consistent with the internal threaded hole 71 at the mating end to ensure a fit with the small-diameter external thread 41. The thread of the small-diameter internal threaded hole 32 taps from the external hexagonal head 33 towards the screw head, with a thread depth of approximately 2 / 3 of the through-hole length. The through-hole diameter is 0.2 mm larger than the nominal diameter of the locking screw 4 to ensure that the locking screw 4 passes through the socket screw normally. The socket screw 3 has an external hexagonal head 33, which serves as the tightening force point for the socket screw. The overall length of the socket screw is determined by the sum of the length of the large-diameter external thread 31, the recommended thickness of the printed circuit board, the thickness of the flat washer, and the thickness of the external hexagon head 33. At the same time, it is ensured that the movable length b of the locking screw 4 after the socket screw is tightened is at least 0.5mm greater than the effective screwing depth a of the internal thread hole 71 at the mating end, so as to ensure that the locking screw 4 can be properly withdrawn from the internal thread hole 71 at the mating end.

[0028] The locking screw 4 is equipped with a small-diameter external thread 41, the thread specification of which matches the specification of the internal threaded hole 71 at the mating end. It is used for mating and locking. The small-diameter external thread 41 is tapped from the screw head to the nut. The thread length is greater than the effective screwing depth a of the internal threaded hole 71 at the mating end by no more than 0.5mm. A long smooth round rod is retained from the thread to the nut. The diameter of the round rod, except for the thread relief groove, is consistent with the nominal diameter of the locking screw 4 to ensure the screw strength.

[0029] The flat washer 5 is configured to be compatible with the sleeve screw specifications. The inner diameter of the washer is 0.2 mm larger than the nominal diameter of the large-diameter external thread 31 of the sleeve screw 3, and the outer diameter of the washer is 1 mm larger than the outer tangent circle diameter of the external hexagon head 33. This ensures that the clamping force on the printed circuit board is effectively distributed when the sleeve screw is tightened, while preventing the printed circuit board from being rubbed by the rotation of the sleeve screw.

[0030] Spring washer 6 is a standard spring washer of the same specification as locking screw 4, which increases the axial force of the screw after tightening to prevent loosening.

[0031] The locking structure for through-hole printed circuit board connectors described in this invention solves the problem of stress on solder joints caused by the inability to independently and mechanically fix the free-end connector to the printed circuit board solder joints, as follows: The sleeve screw 3 serves as an independent locking component. During the electrical assembly stage of the printed circuit board (PCB) and connector, the PCB and connector are assembled first. After assembly, the sleeve screw 3 is screwed into the fixing hole 12 of the housing 1. The tightened sleeve screw 3, together with the support boss 11 of the housing 1, forms a clamping structure to fix the PCB 2. Then, the product begins electrical assembly and soldering. After soldering, the sleeve screw 3 is not disassembled or tightened again to ensure that the solder joint is not subjected to mechanical forces. The locking screw 4 serves as a free-end locking component, locking and fixing the connector 7 at the mating end during the final assembly stage. The sleeve screw 3 and the locking screw 4 are locked relatively independently, simultaneously meeting the mechanical fixing requirements of both the electrical assembly and final assembly stages of the flexible board cable.

Claims

1. A locking structure for a through-hole printed circuit board connector, comprising a printed circuit board (2) and a connector housing (1), characterized in that: The outer casing (1) has support bosses (11) on both sides. The printed circuit board (2) is fixed on the support bosses (11) by sleeve screws (3) on both sides. The locking screw (4) passes through the through hole in the center of the sleeve screw (3) and engages with the mating connector (7).

2. The locking structure for a through-hole printed circuit board connector according to claim 1, characterized in that: The support boss (11) has a large-diameter internal threaded hole (12), and the sleeve screw (3) passes through the through hole on the flexible printed circuit board (2) and engages with the large-diameter internal threaded hole (12).

3. The locking structure for a through-hole printed circuit board connector according to claim 2, characterized in that: The outer wall of the sleeve screw (3) has a large-diameter external thread (31), the upper half of the inner wall of the through hole has a small-diameter internal thread hole (32), and the lower half of the through hole has a smooth structure.

4. The locking structure for a through-hole printed circuit board connector according to claim 3, characterized in that: The locking screw (4) has a small-diameter external thread (41) at the front end, and a long smooth round rod is retained from the thread to the nut section. The specifications of the small-diameter external thread (41) match the small-diameter internal thread hole (32) of the sleeve screw (3).

5. The locking structure for a through-hole printed circuit board connector according to claim 4, characterized in that: The mating structure of the mating connector (7) has a mating end internal thread hole (71), and the small diameter external thread (41) at the front end of the locking screw (4) is engaged with the mating end internal thread hole (71).

6. The locking structure for a through-hole printed circuit board connector according to any one of claims 1-5, characterized in that: The top of the sleeve screw (3) has an external hexagonal structure (33), and a flat washer (5) is provided between the external hexagonal structure (33) and the printed circuit board (2).

7. The locking structure for a through-hole printed circuit board connector according to claim 6, characterized in that: A spring washer (6) is provided between the locking screw (4) and the external hexagonal structure (33).

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