CN115589715A

CN115589715A - SMT double-process production method

Info

Publication number: CN115589715A
Application number: CN202211323181.2A
Authority: CN
Inventors: 黄森村
Original assignee: Weisen Electronics Zhuhai Co ltd
Current assignee: Weisen Electronics Zhuhai Co ltd
Priority date: 2022-10-27
Filing date: 2022-10-27
Publication date: 2023-01-10

Abstract

The invention discloses a production method of an SMT dual process, which comprises the following steps: s1: printing solder paste on a component bonding pad, and printing and coating quantitative solder paste on the bonding pad; s2: printing red glue in the middle of the bonding pad, and printing and coating quantitative red glue in the middle position above the bonding pad; s3: manufacturing a semi-red glue etching steel mesh; s4: the method comprises the following steps of (1) pasting, wherein multiple groups of electronic elements are pasted according to the drawing requirements; s5: and (4) passing through a reflow furnace. According to the production method of the SMT dual-technology, when the SMT is produced, the solder paste is printed on the bonding pad firstly, the solder paste is fixed on the solder paste steel net, red glue is printed in the middle of the bonding pad, the red glue steel net is half-engraved to avoid the printed solder paste, then the welding leg end part of the electronic element and the bonding pad on the PCB are pasted, the PCB which finishes the pasting is processed through a reflow furnace, so that the red glue is solidified to fix the SMT part, the solder paste is melted to weld the SMT part, and the SMT part cannot be subjected to empty welding when the SMT is inserted into the solder furnace.

Description

SMT double-process production method

Technical Field

The invention relates to the technical field of SMT production, in particular to a production method of SMT double processes.

Background

SMT is a circuit assembly technique in which a surface-mounted device without leads or short leads is mounted on a surface or other substrate surface and then soldered or assembled by reflow or dip soldering. SMT is the most popular technique and technology in the electronic assembly industry, and is the technology that is more popular in the electronic assembly industry at present. When various electronic elements are subjected to surface mounting welding on a PCB according to drawing requirements, welding processing needs to be carried out through an SMT (surface mount technology).

The SMT process generally adopts a single red glue or tin paste process, and during the production process of the red glue process, after a product passes through a tin furnace, the phenomenon of empty welding of SMT parts can occur, so that the electronic components are welded unstably and cannot meet the use requirements.

Disclosure of Invention

The invention aims to provide a SMT dual-process production method to solve the problem that the SMT process proposed by the background technology generally adopts a single red glue or tin paste process, and during the production process of the red glue process, empty welding of SMT parts occurs after a product passes through a tin furnace.

In order to achieve the purpose, the invention provides the following technical scheme: a production method of SMT dual process comprises the following steps:

s1: printing solder paste on a component bonding pad, and printing and coating quantitative solder paste on the bonding pad;

s2: printing red glue in the middle of the bonding pad, and printing and coating quantitative red glue in the middle position above the bonding pad;

s3: manufacturing a semi-red glue etching steel mesh;

s4: mounting the electronic elements, namely mounting the electronic elements according to the drawing requirements;

s5: and (4) passing through a reflow oven, and processing the PCB subjected to surface mounting through the reflow oven.

Preferably, the solder paste of step S1 is printed on the upper surface of the component pad to a thickness of 0.12mm.

Preferably, the printing thickness of the red glue in the step S2 is 0.35mm at the upper middle position of the part pad.

Preferably, the steel mesh in step S3 divide into tin cream steel mesh and red gluey steel mesh, with fixed tin cream on the tin cream steel mesh to set up red gluey steel mesh and avoid the good tin cream of printing for half carving the structure.

Preferably, in the step S4, the end of the solder leg of the electronic component is mounted on a pad on the PCB.

Preferably, the reflow furnace in step S5 solidifies the red glue on the bonding pad through high temperature processing to fix the electronic component, and the solder paste melts and bonds the electronic component.

Compared with the prior art, the invention has the beneficial effects that: according to the SMT double-process production method, during SMT production, solder paste is printed on a bonding pad firstly, the solder paste is fixed on a solder paste steel net, red glue is printed in the middle of the bonding pad, the red glue steel net is half-engraved to avoid the printed solder paste, then the welding leg end part of an electronic element and the bonding pad on the PCB are pasted, the PCB which finishes the pasting are processed through a reflow oven, and therefore the red glue is solidified to fix SMT parts, the solder paste is melted to weld the SMT parts, and the SMT parts cannot be subjected to empty welding when the SMT is passed through the solder oven due to the fact that the parts are subjected to tin soldering during SMT production.

Drawings

FIG. 1 is a schematic flow diagram of the present invention;

FIG. 2 is a schematic diagram of the present invention;

FIG. 3 is a schematic front view of the present invention;

FIG. 4 is a right-side cross-sectional structural view of the present invention.

In the figure: 1. a PCB board; 2. an electronic component; 3. a pad; 4. a first steel mesh; 5. tin paste; 6. a second steel mesh; 7. a groove; 8. and (5) red glue.

Detailed Description

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 only a part of the embodiments of the present invention, and not all of the embodiments. 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.

Referring to fig. 1-2, the present invention provides a technical solution: a production method of SMT dual process comprises the following steps:

s1: printing solder paste 5 on the part bonding pad 3, and printing and coating a certain amount of solder paste 5 above the bonding pad 3 during SMT production, wherein the printing thickness of the solder paste 5 on the surface above the part bonding pad 3 is 0.12 mm;

s2: printing red glue 8 in the middle of the bonding pad 3, printing and coating a certain amount of red glue 8 at the middle position above the bonding pad 3, wherein the printing thickness of the red glue 8 at the middle position above the part bonding pad 3 is 0.35mm;

s3: manufacturing a semi-etched red glue steel mesh, wherein the steel mesh is divided into a solder paste steel mesh and a red glue steel mesh, fixing solder paste 5 on the solder paste steel mesh, and arranging the red glue steel mesh as a semi-etched structure to avoid the printed solder paste 5;

s4: the method comprises the following steps of (1) mounting, wherein mounting operation is carried out on a plurality of groups of electronic elements 2 according to the drawing requirements, and the mounting is carried out by correspondingly mounting the end parts of welding pins of the electronic elements 2 and a welding disc 3 on a PCB (printed Circuit Board) 1;

s5: and (4) passing through a reflow furnace, processing the PCB 1 subjected to surface mounting through the reflow furnace, solidifying and fixing the electronic element 2 by the red glue 8 on the bonding pad 3 through high-temperature processing in the reflow furnace, and melting and welding the electronic element 2 by the solder paste 5.

When specifically implementing, earlier seal tin cream 5 on part pad 3 during SMT production, again in the middle of pad 3 red glue 8 of seal, red gluey steel mesh is made half carving and is avoided tin cream 5 printed, carry out the paster again, cross the fixed SMT part of 8 solidification of red gluey behind the reflow oven, tin cream 5 melts the welding SMT part, because the part has gone up tin welding during SMT production, empty welding phenomenon just can not appear in the SMT part when plug-in components cross the tin oven, and then reduce the maintenance rate, improve whole welding process's quality and production efficiency.

Examples

Referring to fig. 3-4, it can be known that the SMT dual-process production method includes a PCB board 1 and a bonding pad 3, a plurality of electronic components 2 are fixedly arranged on the upper surface of the PCB board 1, the bonding pad 3 is arranged at a position, corresponding to the electronic components 2, of the PCB board 1, a first steel mesh 4 is arranged at the upper end of the bonding pad 3, solder paste 5 is fixedly arranged at the upper end of the first steel mesh 4, a second steel mesh 6 is further arranged at the upper end of the first steel mesh 4, a groove 7 corresponding to the solder paste 5 is formed in the lower end of the second steel mesh 6, and red glue 8 is fixedly arranged at the upper end of the second steel mesh 6.

First steel mesh 4 is the tin cream steel mesh, second steel mesh 6 is red gluey ladder steel mesh, and the thickness of second steel mesh 6 is greater than the thickness of first steel mesh 4, the degree of depth of recess 7 is greater than the printing thickness of tin cream 5, the printing thickness of tin cream 5 is 0.12mm, the printing thickness of red gluey 8 is 0.35mm.

Print red glue 8 earlier when the printing, print tin cream 5 again, can avoid printing good tin cream 5 to suffer destruction, reflow oven is crossed to SMT production paster, and red 8 solidification fixed part that glue, tin cream 5 melt welding part, wave-soldering equipment is crossed after the encapsulation is accomplished to DIP station to SMT electronic component solder joint does not have the bad phenomenon of empty solder, thereby effectively improves the quality and the personnel efficiency of product.

In summary, in the SMT production, 0.12mm of solder paste 5 is printed and coated on the upper side of the pad 3, 0.35mm of red glue 8 is printed and coated on the middle position of the upper side of the pad 3, the solder paste 5 is fixed on the solder paste steel mesh, and the red glue steel mesh is arranged to be in a half-etching structure to avoid the printed solder paste 5, the end portion of the solder leg of the electronic component 2 is pasted and corresponds to the pad 3 on the PCB 1, the pasted PCB 1 is processed through a reflow oven, so that the reflow oven solidifies the electronic component 2 by high-temperature processing to fix the red glue 8 on the pad 3, and the electronic component 2 is welded by melting the solder paste 5, thereby stably welding the SMT component and avoiding the empty welding phenomenon.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.

Claims

1. The production method of the SMT dual process is characterized by comprising the following steps:

s1: printing solder paste (5) on the part bonding pad (3), and printing and coating a certain amount of solder paste (5) above the bonding pad (3);

s2: printing red glue (8) in the middle of the bonding pad (3), and printing and coating quantitative red glue (8) at the middle position above the bonding pad (3);

s3: manufacturing a semi-red glue etching steel mesh;

s4: the method comprises the following steps of (1) pasting, wherein multiple groups of electronic elements (2) are pasted according to the drawing requirements;

s5: and (4) passing through a reflow oven, and processing the PCB (1) with the surface mounted by the reflow oven.

2. An SMT dual process production method according to claim 1, wherein: and (2) printing the solder paste (5) with the thickness of 0.12mm on the upper surface of the part bonding pad (3) in the step (S1).

3. An SMT dual process production method according to claim 1, wherein: and the printing thickness of the red glue (8) in the step S2 is 0.35mm at the middle position above the part bonding pad (3).

4. An SMT dual process production method according to claim 1, wherein: and the steel mesh in the step S3 is divided into a solder paste steel mesh and a red glue steel mesh, solder paste (5) is fixed on the solder paste steel mesh, and the red glue steel mesh is arranged to be of a half-etching structure to avoid the printed solder paste (5).

5. An SMT dual process production method according to claim 1, wherein: and in the step S4, the end part of the welding leg of the electronic element (2) is pasted and corresponds to the welding pad (3) on the PCB (1).

6. An SMT dual process production method according to claim 1, wherein: and in the step S5, the reflow furnace solidifies the red glue (8) on the bonding pad (3) through high-temperature processing to fix the electronic element (2), and the solder paste (5) melts and welds the electronic element (2).