阅读说明：本技术 车载充电机半导体晶体管的先装后焊结构和方法 (Structure and method for mounting and welding semiconductor transistor of vehicle-mounted charger first ) 是由 刘钧 冯颖盈 姚顺 罗耀文 肖伟军 于 2019-09-23 设计创作，主要内容包括：本发明提供了一种车载充电机半导体晶体管的先装后焊结构和方法,该结构包括：壳体、塑胶支架、弹片、半导体晶体管和电路板,半导体晶体管粘贴在塑胶支架的一侧,弹片安装在壳体内,弹片将塑胶支架上的半导体晶体管的一侧压紧贴合在壳体内的水道侧壁上,电路板固定地安装在半导体晶体管及水道的上方,半导体晶体管的引脚在未焊接之前穿设在电路板上的焊接通孔中。本发明将现有技术中的先焊后装方案改进为先装后焊方案,从而避免了半导体晶体管的引脚、焊点受到很大的应力,造成功能失效的问题,同时也避免了由于半导体晶体管引脚先被焊住再压紧,导致半导体晶体管不能很好的贴合在散热器上,导致散热不良的问题。(The invention provides a structure and a method for mounting and welding a semiconductor transistor of a vehicle-mounted charger, wherein the structure comprises the following steps: the semiconductor transistor is adhered to one side of the plastic support, the elastic sheet is installed in the shell, one side of the semiconductor transistor on the plastic support is pressed and attached to the side wall of the water channel in the shell through the elastic sheet, the circuit board is fixedly installed above the semiconductor transistor and the water channel, and pins of the semiconductor transistor penetrate through welding through holes in the circuit board before welding. The invention improves the prior art of the scheme of welding first and then welding into the scheme of welding first and then welding, thereby avoiding the problem of functional failure caused by the fact that the pins and welding points of the semiconductor transistor are stressed greatly, and simultaneously avoiding the problem of poor heat dissipation caused by the fact that the pins of the semiconductor transistor are welded and then pressed tightly, which leads to the fact that the semiconductor transistor cannot be well attached to a radiator.)

1. The utility model provides a structure is welded after dress of on-vehicle machine semiconductor transistor that charges which characterized in that includes: casing (1), plastic support (2), shell fragment (3), semiconductor transistor (4) and circuit board (5), semiconductor transistor (4) are fixed one side of plastic support (2), install shell fragment (3) in casing (1), shell fragment (3) will one side of semiconductor transistor (4) on plastic support (2) compresses tightly the laminating and is in on water course (6) lateral wall in casing (1), circuit board (5) are installed fixedly semiconductor transistor (4) reach the top of water course (6), the pin of semiconductor transistor (4) is worn to establish before the non-welding in the welding through-hole on circuit board (5).

2. The structure of the vehicle-mounted charger semiconductor transistor that is welded after being installed firstly according to claim 1, characterized in that the plastic support (2) comprises a back plate (7), a top plate (8) and a positioning pin (9), the top plate (8) is vertically connected with the upper end of the back plate (7), the positioning pin (9) is installed at the lower end of the back plate (7), and a positioning jack matched with the positioning pin (9) is arranged in the housing (1).

3. The semiconductor transistor mounting-welding structure of the vehicle-mounted charger according to claim 2, characterized in that a semiconductor transistor positioning boss (10) is protrudingly formed on the back plate (7), and a pin positioning groove (11) is formed on the top plate (8).

4. The structure of the vehicle-mounted charger semiconductor transistor of claim 2, characterized in that the semiconductor transistor (4) is bonded to the back plate (7) by a double-sided adhesive tape (12).

5. The structure of the semiconductor transistor of the vehicle-mounted charger according to claim 1, characterized in that a heat-conducting insulating film (13) is arranged between the semiconductor transistor (4) and the water channel (6).

6. The structure of a semiconductor transistor of a vehicle-mounted charger according to claim 1, characterized in that the casing (1) is integrally formed with the water channel (6).

7. The structure for mounting and welding the semiconductor transistor of the vehicle-mounted charger according to claim 6, characterized in that the structure for mounting and welding the semiconductor transistor of the vehicle-mounted charger further comprises a water channel cover plate (14), and the water channel (6) is hermetically connected with the water channel cover plate (14) through a sealing ring (15).

8. The structure for mounting a semiconductor transistor of a vehicle-mounted charger according to claim 6, wherein the cross section of the water channel (6) is L-shaped, and the bottom of the L-shaped water channel extends into the lower part of the mounting cavity surrounded by the water channel (6).

9. The structure for the semiconductor transistor of the vehicle-mounted charger according to claim 1, characterized in that the semiconductor transistor (4) is perpendicular to the circuit board (5) and parallel to the water channel (6), the height of the water channel (6) is much greater than the width thereof, and the height of the cooling liquid in the water channel (6) reaches the heat dissipation surface of the semiconductor transistor (4).

10. The structure for the semiconductor transistor of the vehicle-mounted charger according to claim 8, characterized in that a power magnetic member (16) is arranged in the mounting cavity.

11. The semiconductor transistor structure of the vehicle-mounted charger according to claim 10, wherein the power magnetic member (16) conducts heat with the water channel (6) by applying a thermal conductive paste or pouring a thermal conductive paste or padding a thermal conductive pad.

12. The semiconductor transistor structure of the vehicle-mounted charger according to claim 1, wherein an electrolytic capacitor (17) and an AC common mode inductor (18) are arranged in the housing (1), and the electrolytic capacitor (17) and the AC common mode inductor (18) conduct heat with the housing (1) in a manner of dispensing heat-conducting glue, pouring heat-conducting glue, or padding a heat-conducting pad.

13. The structure of the vehicle-mounted charger semiconductor transistor, which is welded after being assembled, according to claim 1, is characterized in that the elastic sheet (3) is fixed on the shell (1) through a screw, and the section of the elastic sheet (3) is L-shaped.

14. A method for mounting and welding a semiconductor transistor of a vehicle-mounted charger is characterized by comprising the following steps:

step 1, adhering a high-temperature resistant adhesive substance on a plastic support (2);

step 2, mounting a semiconductor transistor (4) on the plastic support (2) through the high-temperature-resistant adhesive substance;

step 3, arranging the plastic support (2) and the semiconductor transistor (4) on one side of the side wall of the water channel (6) in the shell (1);

step 4, installing the elastic sheet (3) into the shell (1) through a screw so that the elastic sheet (3) provides pressing force for the plastic support (2) and the semiconductor transistor (4) is pressed on the side wall of the water channel in the shell (1);

step 5, mounting a circuit board (5) on the shell (1), and enabling pins of the semiconductor transistor (4) to penetrate through welding through holes in the circuit board (5);

and 6, welding the shell (1) with the circuit board (5), so that pins of the semiconductor transistor (4) are welded on the circuit board (5).