Welding tooling and welding method for a multi-element surface-mounted RF connector

Abstract

The present invention discloses a welding tooling and a welding method for a multi-element surface-mounted radio frequency connector. The welding tooling includes a base, a cover plate and a mother board. A first limiting frame and a second limiting frame are arranged on the base. The first limiting frame is used for placing the mother board, and the second limiting frame is used for placing the cover plate. Positioning holes are formed in the cover plate. The number of the positioning holes is the same as the number of the radio frequency connectors and is used for restricting the movement of the connector housing. A plurality of positioning posts are arranged on the cover plate and are used for restricting the movement of the surface-mounted pins of the connector. Each positioning hole corresponds to two positioning posts, and two adjacent positioning posts are located on both sides of the positioning hole. Ventilation holes are formed in the base, and the ventilation holes of the base are located on the side surface and the bottom surface of the base. Ventilation holes are formed in the cover plate, and the ventilation holes of the cover plate are located around the positioning holes. The present invention can improve the temperature uniformity and the welding quality in the welding process of the multi-element surface-mounted radio frequency connector, solve the problems of low welding precision and poor consistency of the surface-mounted radio frequency connector, and effectively improve the manual welding production efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of microelectronic packaging, and particularly relates to a welding tooling and a welding method for a multi-element surface-mounted radio frequency connector. Background Art

[0002] In recent years, with the development of radar towards high integration, high performance, miniaturization and other directions, the volume of each subsystem of the radar is small, the integration degree is high, the interconnection methods are relatively diverse, the assembly and maintenance of the subsystems are more difficult, and the packaging and interconnection technologies based on the radar subsystems also face new development requirements.

[0003] The system-level interconnection based on the multi-element surface-mounted radio frequency connector realizes plug-in connection with multiple ports of the subsystem through the surface-mounted radio frequency connector, and has the advantages of simple assembly, low cost, easy maintenance, etc. Due to the high system integration degree, the number of channels on a single motherboard of the subsystem is large, and the corresponding number of radio frequency connectors is also large. And the connector ports are related to the radio frequency transmission performance and the interconnection communication between subsystems. Therefore, the welding quality and precision of the connectors are very important.

[0004] The welding technology of the multi-element surface-mounted radio frequency connector has made significant development, but there are still the following problems: (1) In practical applications, in addition to the connectors on the motherboard, there are other welding components on both the front and back sides of the motherboard. Due to factors such as component blocking, welding tooling isolation, and uneven device distribution, when hot air reflow or vapor phase reflow is carried out, the heating rate of different regions of the motherboard is different, resulting in phenomena such as poor welding or over-welding of the connectors and surrounding components, and poor welding quality; (2) The corresponding plug-in interface positions of the multi-element surface-mounted radio frequency connectors are fixed. As long as one of the connectors is offset after welding, the connector array cannot be plugged into the corresponding interfaces simultaneously, and then the multi-element connector micro-system sub-array cannot be connected to other systems. When the surface-mounted radio frequency connector is reflow soldered, due to the absence of obstacles around the connector and factors such as the welding environment and solder flow, it is difficult to control the welding precision, resulting in uncontrollable offset of the connector in any direction after welding, and poor welding consistency; (3) The outer shell of the surface-mounted radio frequency connector is cylindrical, and there are direction requirements during surface mounting. It is difficult to make alignment marks on the connector outer shell, which is not suitable for machine automation production. And the number of connectors is large, the manual placement and welding efficiency is low, and the manual welding precision is difficult to guarantee, increasing the rework workload and further reducing the production efficiency. Summary of the Invention

[0005] The purpose of the present invention is to provide a welding tooling and a welding method for a multi-element surface-mounted radio frequency connector, which can improve the temperature uniformity and welding quality during the welding process of the multi-element surface-mounted radio frequency connector, solve the problems of low welding precision and poor consistency of the surface-mounted radio frequency connector, and effectively improve the manual welding production efficiency.

[0006] One aspect of the present invention provides a soldering tooling for a multi-element surface-mounted RF connector, including a base, a cover plate and a mother board. A first limiting frame and a second limiting frame are arranged on the base. The first limiting frame is used for placing the mother board, and the second limiting frame is located above the first limiting frame and is used for placing the cover plate. Solder pads are arranged on the mother board for soldering with the connector. The RF connector includes a connector housing and connector surface-mounted pins;

[0007] Positioning holes are formed in the cover plate. The number of the positioning holes is the same as that of the RF connectors and is used for restricting the movement of the connector housing;

[0008] A plurality of positioning posts are arranged on the cover plate for restricting the movement of the connector surface-mounted pins. Each positioning hole corresponds to two positioning posts, and the adjacent two positioning posts are located on both sides of the positioning hole. The difference between the distance from the cover plate to the mother board and the length of the positioning post is 0.02 - 1 mm, and the difference between the distance between the adjacent two positioning posts and the diameter of the connector surface-mounted pin is 0.02 - 1 mm;

[0009] Ventilation holes are formed in the base. The ventilation holes of the base are located on the side surface and the bottom surface of the base. The ventilation holes on the side surface are located between two adjacent RF connectors, and the ventilation holes on the bottom surface are located below the solder pads of the mother board;

[0010] Ventilation holes are formed in the cover plate. The ventilation holes of the cover plate are located around the positioning holes.

[0011] Preferably, the difference between the diameter of the positioning hole and the diameter of the RF connector is 0.01 - 1 mm.

[0012] Preferably, the unilateral offset of the mother board placed in the first limiting frame is 0.05 - 1 mm; the unilateral offset of the cover plate placed in the second limiting frame is 0.05 - 1 mm.

[0013] Preferably, the materials of the base and the cover plate are one or several of aluminum, aluminum alloy and graphite.

[0014] Another aspect of the present invention provides a soldering method for a multi-element surface-mounted RF connector. The soldering tooling described above is used for soldering the multi-element surface-mounted RF connector. The method includes:

[0015] Adopt the method of stencil printing to print a layer of solder paste on the surface of the solder pads of the mother board;

[0016] Place the mother board in the first limiting frame of the base;

[0017] Place the cover plate in the second limiting frame of the base;

[0018] Place the RF connector on the corresponding pads of the motherboard through the positioning holes on the cover plate;

[0019] Put the placed connector and the soldering tooling into the reflow oven together for reflow soldering;

[0020] After the reflow soldering is completed, remove the soldering tooling to obtain the soldered multi-chip surface-mount RF connector.

[0021] Preferably, the solder paste is one of SAC305, SnPb37, and SnBi58.

[0022] According to the soldering tooling and soldering method of the multi-chip surface-mount RF connector in the above aspect of the present invention, it can improve the temperature uniformity and soldering quality during the soldering process of the multi-chip surface-mount RF connector, solve the problems of low soldering accuracy and poor consistency of the surface-mount RF connector, and effectively improve the production efficiency of manual soldering. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts:

[0024] Figure 1 It is a schematic structural diagram of the soldering tooling for the multi-chip surface-mount RF connector according to an embodiment of the present invention;

[0025] Figure 2 It is a top view of the base of the soldering tooling according to an embodiment of the present invention;

[0026] Figure 3 It is a top view of the cover plate of the soldering tooling according to an embodiment of the present invention;

[0027] Figure 4 It is a side cross-sectional view of the soldering tooling according to an embodiment of the present invention.

[0028] Among them, 1 - base, 2 - first limiting frame, 3 - second limiting frame, 4 - ventilation holes on the side of the base, 5 - ventilation holes on the bottom of the base, 6 - cover plate, 7 - positioning holes, 8 - positioning posts, 9 - motherboard, 10 - connector pads, 11 - RF connector, A - diameter of the positioning hole, B - diameter of the RF connector, C - distance from the cover plate to the motherboard, D - length of the positioning post, E - distance between adjacent two positioning posts, F - diameter of the surface-mount pins of the RF connector, G - unilateral offset of the motherboard placed in the first limiting frame, H - unilateral offset of the cover plate placed in the second limiting frame. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0030] An embodiment of the present invention provides a soldering tooling for a multi-element surface-mounted RF connector. Figure 1 It is a schematic structural diagram of the soldering tooling for a multi-element surface-mounted RF connector according to an embodiment of the present invention. In Figure 1 the illustrated embodiment, the multi-element surface-mounted RF connector is a 64-element surface-mounted RF connector. As Figures 1-3 shown, the soldering tooling of the embodiment of the present invention includes a base 1, a cover plate 6 and a mother board 9. A first limit frame 2 and a second limit frame 3 are provided on the base 1. The first limit frame 2 is used to place the mother board 9, and the second limit frame 3 is located above the first limit frame 2 and is used to place the cover plate 6. Solder pads 10 are provided on the mother board 9 for soldering with the RF connector 11, and the RF connector 11 includes a connector housing and connector surface-mounted pins.

[0031] As Figure 4 shown, the unilateral offset of the mother board 9 placed in the first limit frame 2 is G, and the value range of G is 0.05 - 1 mm; the unilateral offset of the cover plate 6 placed in the second limit frame 3 is H, and the value range of H is 0.05 - 1 mm. Preferably, the unilateral offset G is 0.05 mm and the unilateral offset H is 0.05 mm.

[0032] A plurality of positioning holes 7 are formed on the cover plate 6. The number of the positioning holes 7 is the same as the number of the surface-mounted RF connectors 11 and is used to accommodate the surface-mounted RF connectors 11. As Figure 4 shown, the difference between the diameter A of the positioning hole 7 and the diameter B of the surface-mounted RF connector 11 is I = A - B, and the value range of I is 0.01 - 1 mm. This difference only needs to meet the requirements of the mounting accuracy. Preferably, the difference I is 0.05 mm.

[0033] A plurality of positioning posts 8 are provided on the cover plate 6. Each positioning hole 7 corresponds to two positioning posts 8, and the two positioning posts 8 are located on both sides of the positioning hole 7. As Figure 4As shown, the difference J between the distance C from the cover plate 6 to the mother board 9 and the length D of the positioning post 8 is J = C - D, and the value range of J is 0.02 to 1 mm; the difference K between the distance E between two adjacent positioning posts and the diameter F of the surface-mounted pins of the RF connector is K = E - F, and the value range of K is 0.02 to 1 mm. Preferably, the difference J between the distance C from the cover plate 6 to the mother board 9 and the length D of the positioning post 8 is 0.4 mm; the difference K between the distance E between two adjacent positioning posts 8 and the diameter F of the surface-mounted pins of the RF connector is 0.05 mm.

[0034] In one embodiment, the base 1 is provided with ventilation holes. The ventilation holes of the base are located on the side and bottom surfaces of the base 1. The side ventilation holes 4 are located between two adjacent connectors 11, and the bottom ventilation holes 5 are located below the pads 10 of the connectors 11 on the mother board 9. The cover plate 6 is provided with ventilation holes, and the cover plate ventilation holes are located around the positioning holes 7 of the cover plate 6.

[0035] In one embodiment, the materials of the base 1 and the cover plate 6 are one or several of aluminum, aluminum alloy, and graphite. Preferably, the materials of the base 1 and the cover plate 6 are aluminum alloy.

[0036] An embodiment of the present invention further provides a welding method for a multi-element surface-mounted RF connector. The welding tooling of the above embodiment is used for welding the multi-element surface-mounted RF connector, including the following steps:

[0037] 1) Adopt the method of stencil printing to print a layer of solder paste on the surface of the pad 10 of the mother board 9.

[0038] 2) Place the mother board 9 in the first limit frame 2 of the base 1 with the surface of the printed solder paste facing up.

[0039] 3) Place the cover plate 6 in the second limit frame 3 of the base 1 with the side with the positioning posts 8 facing down.

[0040] 4) Place the connector 11 on the corresponding pad 10 of the mother board 9 through the positioning hole 7 on the cover plate 6. Specifically, the connector 11 can be clamped with tweezers and placed into the positioning hole 7 on the cover plate 6 in sequence to make the connector 11 align and contact with the corresponding pad 10 on the mother board 9.

[0041] 5) Place the placed connector and the welding tooling together into a reflow oven for reflow soldering, and take them out after the reflow is completed.

[0042] 6) When the surface temperature of the tooling drops to room temperature, remove the welding tooling to obtain the welded multi-element surface-mounted RF connector.

[0043] In one embodiment, the solder paste is one of SAC305, SnPb37, and SnBi58. Preferably, the solder paste is SAC305.

[0044] In summary, the soldering tooling and soldering method for the multi-element surface-mounted RF connector according to the embodiments of the present invention achieve the following: 1) Ventilation holes are provided on both the base and the cover plate to improve temperature uniformity; 2) Positioning holes and positioning posts are provided on the cover plate to restrict the movement of the connector; 3) The limit frame and the positioning holes can achieve precise alignment of the connector, thereby improving the temperature uniformity and soldering quality during the soldering process of the connector, solving the problems of low soldering accuracy and poor consistency of the surface-mounted RF connector, and effectively improving the manual soldering production efficiency.

[0045] Specifically, the soldering tooling and soldering method for the multi-element surface-mounted RF connector according to the embodiments of the present invention produce the following beneficial effects:

[0046] 1. In the present invention, ventilation holes are opened on the side and bottom of the base 1 of the soldering tooling and on the surface of the cover plate 6. During the reflow soldering process, heat sources such as hot air or vapor-phase liquid steam can gather from the ventilation holes to the surface of the motherboard 9, make full contact with the connector 11, heat the connector 11 from all directions, ensure a consistent heating rate, enable the solder to quickly reach the soldering temperature, ensure sufficient melting of the solder, and achieve high-quality soldering.

[0047] 2. In the present invention, by controlling the external dimensions and relative positions of the first limit frame 2, the second limit frame 3, the cover plate 6, and the positioning holes 7, it is ensured that when the connector 11 is placed through the positioning holes 7, the connector 11 can be accurately aligned with the pads 10 of the motherboard 9, ensuring soldering consistency. Moreover, the positioning holes 7 are provided on one cover plate 6, which can limit the overall offset error of the connector, further improving the soldering consistency of the connector.

[0048] 3. In the present invention, positioning holes 7 and positioning posts 8 for the connector 11 are provided on the cover plate 6. The positioning posts 8 can restrict the movement of the surface-mounted pins of the connector, and the positioning holes 7 can restrict the movement of the connector housing, thereby restricting the overall offset of the connector. During the production process, the connector only needs to be directly placed on the pads 10 of the motherboard 9 through the positioning holes 7, without manual alignment, improving the manual production efficiency. Moreover, by further setting the dimensions and height of the positioning posts 8, while the positioning posts 8 restrict the movement of the surface-mounted pins of the connector, they can also not contact the solder paste, will not affect the flow of the solder, ensure the soldering quality, and ensure the soldering reliability.

[0049] Only some exemplary embodiments of the present invention have been described by way of illustration. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A welding tool based on a multi-element surface mount radio frequency connector, characterized in that: The RF connector comprises a base, a cover plate and a motherboard, wherein the base is provided with a first limit frame and a second limit frame, wherein the first limit frame is used to place the motherboard, and the second limit frame is located above the first limit frame and is used to place the cover plate, wherein the RF connector comprises a connector housing and a connector surface mount pin, and a solder pad is provided on the motherboard for soldering with the connector surface mount pin; The cover plate is provided with positioning holes, the number of which is the same as the number of the RF connectors, for limiting the movement of the connector housing; The cover plate is provided with a plurality of positioning posts for limiting the movement of the connector surface mount pins. Each positioning hole corresponds to two positioning posts, and two adjacent positioning posts are located on both sides of the positioning hole. The difference between the distance from the cover plate to the motherboard and the length of the positioning posts is 0.02 to 1 mm, and the difference between the distance between two adjacent positioning posts and the diameter of the connector surface mount pins is 0.02 to 1 mm. The base is provided with ventilation holes, and the ventilation holes of the base are located on the side and bottom of the base, the ventilation holes on the side are located between two adjacent RF connectors, and the ventilation holes on the bottom are located below the solder pads of the motherboard; The cover plate is provided with ventilation holes, and the ventilation holes of the cover plate are located around the positioning hole.

2. The welding tool according to claim 1, characterized in that: The difference between the diameter of the positioning hole and the diameter of the radio frequency connector is 0.01-1 mm.

3. The welding tool according to claim 1 or 2, characterized in that: The single-side offset of the motherboard placed on the first limiting frame is 0.05-1 mm; the single-side offset of the cover plate placed on the second limiting frame is 0.05-1 mm.

4. The welding tool according to claim 1 or 2, characterized in that: The base and the cover are made of one or more of aluminum, aluminum alloy and graphite.

5. A welding method for a multi-element surface mount radio frequency connector, characterized in that: Using the welding tool described in any one of claims 1 to 4 to weld a multi-element surface mount radio frequency connector, the method comprising: A layer of solder paste is printed on the pad surface of the motherboard by using steel screen printing; Placing the motherboard in the first limiting frame of the base; Placing the cover plate in the second limiting frame of the base; Place the RF connector on the corresponding pad of the motherboard through the positioning hole on the cover; Put the placed connector and the welding tooling into the reflow oven for reflow soldering; After the reflow soldering is completed, the soldering tooling is removed to obtain a soldered multi-element surface-mount RF connector.

6. The welding method according to claim 5, characterized in that: The solder paste is one of SAC305, SnPb37 and SnBi58.

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