Semiconductor rectifier injection molding packaging device

Abstract

The utility model discloses a semiconductor rectifier injection molding packaging device which comprises an upper mold, a lower mold, a base, a supporting column, a protective cover, a material injection pipe, a first air cylinder, a piston, a sealing plate, an upper cylinder body, a lower cylinder body, a metal telescopic sleeve, an annular hanging frame, a connecting rod, a second air cylinder and a circulating cooling water pipe. The four supporting columns are distributed in a rectangular mode, the upper ends and the lower ends of the supporting columns are fixedly connected with the upper mold and the base respectively, the lower mold is slidably installed on the supporting columns, and the lower mold and the upper mold are matched to form a plastic packaging mold cavity. Hot resin in the lower cylinder body is extruded through downward expansion of the metal telescopic sleeve and is injected into the plastic packaging mold cavity through the material injection pipe and the pouring gate for plastic packaging operation, the requirement for the machining precision of the piston, the inner hole of the upper cylinder body and the inner hole of the lower cylinder body can be lowered, and therefore the machining cost can be lowered; the piston cannot be blocked when the piston moves up and down and the metal telescopic sleeve does stretching / contracting movement, and the piston has the advantages of being high in use reliability and long in service life.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor plastic packaging, in particular to a semiconductor rectifier injection molding packaging device. Background Art

[0002] The semiconductor rectifier chip and lead frame that have completed wire bonding are placed in the plastic encapsulation mold for plastic encapsulation. The chip, metal lead and bracket are wrapped and protected with plastic encapsulation material, and the appearance of the plastic encapsulation material is formed at the same time. The temperature of the hot resin in the flowing state used for plastic encapsulation is usually 90-120℃. In order to prevent the hot resin from passing through the injection mechanism piston and contacting its sealing ring, causing high-temperature aging and piston movement blockage, it is usually necessary to set the surface roughness of the cylinder body bore and the outer surface of the piston of the injection mechanism to Ra0.0025-Ra0.005, and the straightness of the cylinder body bore and the outer surface of the piston to 0.015mm-0.02mm, so as to reduce the wear problem between the outer surface of the piston and the cylinder body bore, thereby ensuring the reliability and service life of the processing operation. This high-precision processing of the injection mechanism cylinder and piston has the disadvantage of high cost. Summary of the invention

[0003] The technical problem to be solved by the utility model is to provide a semiconductor rectifier injection molding packaging device which has low requirements on the inner hole of the cylinder body and the piston processing accuracy of the injection mechanism and will not cause the problem of piston jamming.

[0004] In order to solve the above technical problems, the present invention is achieved through the following technical solutions: a semiconductor rectifier injection packaging device, including an upper mold, a lower mold, a base, a support column, a protective cover, an injection tube, a first cylinder, a piston, a sealing plate, an upper cylinder body, a lower cylinder body, a metal telescopic sleeve, an annular hanger, a connecting rod, a second cylinder and a circulating cooling water pipe, four support columns are distributed in a rectangular shape, and their upper and lower ends are respectively fixedly connected to the upper mold and the base, the lower mold is slidably mounted on the support column, and the lower mold cooperates with the upper mold to form a plastic sealing mold cavity, the cylinder body of the second cylinder is fixedly mounted on the base, the piston rod of the second cylinder is fixedly connected to the lower mold, the protective cover is fixedly mounted on the top of the upper mold, the cylinder body of the first cylinder is fixedly mounted on the protective cover, the sealing plate is fixedly mounted on the protective cover, the upper cylinder body is fixedly mounted on the top of the protective cover, and the bottom of the lower cylinder body The cam is sealed and fixedly connected to a sealing plate, wherein an injection interface connected to the lower cylinder body is arranged on the sealing plate, the top of the lower cylinder body is screwed and sealed and fixedly connected to the bottom of the upper cylinder body, the annular hanging bracket is pressed and sealed and fixedly installed between the top of the lower cylinder body and the bottom of the upper cylinder body, the top of the metal telescopic sleeve is sealed and fixedly hung and installed at the bottom of the annular hanging bracket, the piston is slidably installed in the upper cylinder body, the bottom of the metal telescopic sleeve is arranged as a sealing structure, the bottom of the piston is fixedly connected to the bottom of the metal telescopic sleeve through a connecting rod, a groove is arranged at the center position of the bottom of the upper mold, a support block is fixedly installed in the groove, the injection tube is sealed and fixedly installed on the sealing plate, the upper mold and the support block, the plastic sealing mold cavity and the groove are provided with a connected runner, the circulating cooling water pipe is arranged in the upper mold and the lower mold, and electric heating wires are wound around the outer walls of the upper and lower cylinder bodies.

[0005] Preferably, the bottom of the injection tube is configured as a sealing structure, and a discharge hole is provided in a ring shape at the bottom of the injection tube.

[0006] Preferably, the bottom surface of the piston is configured as a spherical structure.

[0007] Preferably, a guide sleeve is fixedly mounted on the lower mold, and the guide sleeve is slidably mounted on the support column.

[0008] Compared with the prior art, the utility model has the following advantages: the hot resin in the lower cylinder body is squeezed out by the downward expansion of the metal telescopic sleeve and injected into the plastic sealing mold cavity through the injection pipe and the runner for plastic sealing operation, which can reduce the requirements for the processing accuracy of the piston and the inner holes of the upper cylinder body and the lower cylinder body, thereby reducing the processing cost. At the same time, during the plastic sealing operation, the up and down movement of the piston and the expansion / contraction movement of the metal telescopic sleeve will not cause jamming problems, and the utility model has the advantages of high reliability and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The utility model is further described below in conjunction with the accompanying drawings.

[0010] Figure 1 It is a structural schematic diagram of the utility model.

[0011] Figure 2 yes Figure 1 Enlarged structural diagram at M. DETAILED DESCRIPTION

[0012] The utility model is described in detail below in conjunction with specific implementation methods:

[0013] like Figure 1 to Figure 2The semiconductor rectifier injection molding packaging device shown in the figure includes an upper mold 1, a lower mold 2, a base 3, a support column 4, a protective cover 5, an injection tube 50, a first cylinder 51, a piston 52, a sealing plate 54, an upper cylinder body 61, a lower cylinder body 62, a metal telescopic sleeve 63, an annular hanger 64, a connecting rod 7, a second cylinder 8 and a circulating cooling water pipe 9. The four support columns 4 are distributed in a rectangular shape, and their upper and lower ends are respectively fixedly connected to the upper mold 1 and the base 3. The lower mold 2 is slidably mounted on the support column 4. The lower mold 2 cooperates with the upper mold 1 to form a plastic sealing mold cavity 101. The cylinder body of the second cylinder 8 is fixedly mounted on the base 3. The piston rod of the second cylinder 8 is fixedly connected to the lower mold 2, the protective cover 5 is fixedly installed on the top of the upper mold 1, the cylinder body of the first cylinder 51 is fixedly installed on the protective cover 5, the sealing plate 54 is fixedly installed on the protective cover 5, the upper cylinder body 61 is fixedly installed on the top of the protective cover 5, the bottom of the lower cylinder body 62 is sealed and fixedly connected to the sealing plate 54, and the sealing plate 54 is provided with an injection interface 55 connected to the lower cylinder body 62. The top of the lower cylinder body 62 is screwed and sealed and fixedly connected to the bottom of the upper cylinder body 61. The annular hanging bracket 64 is pressed and sealed and fixedly installed between the top of the lower cylinder body 62 and the bottom of the upper cylinder body 61. The top of the telescopic sleeve 63 is sealed and fixedly hung and installed at the bottom of the annular hanger 64. The piston 52 is slidably installed in the upper cylinder body 61. The bottom of the metal telescopic sleeve 63 is set as a sealing structure. The bottom of the piston is fixedly connected to the bottom of the metal telescopic sleeve 63 through a connecting rod 7. A groove 11 is provided at the center of the bottom of the upper mold 1. A support block 13 is fixedly installed in the groove 11. The injection pipe 50 is sealed and fixedly installed on the sealing plate 54, the upper mold 1, and the support block 13. The plastic sealing mold cavity 101 and the groove 11 are provided with a connected runner 12. The circulating cooling water pipe 9 is provided on the upper mold 1 and the lower mold 2 Inside, electric heating wires are wound around the outer walls of the upper cylinder body 61 and the lower cylinder body 62. Starting the electric heating wires can also melt the condensed resin in the lower cylinder body 62 and the injection tube 50 for use. The areas between the upper cylinder body 61, the lower cylinder body 62 and the protective cover 5, and the area between the sealing plate 54 and the upper mold 1 are filled with insulation materials to insulate the hot resin flowing in the lower cylinder body 62 and the injection tube 50 to prevent it from cooling and condensing. A temperature sensor is arranged in the insulation material, and the temperature sensor is connected to a temperature display located outside the protective cover 5 through a circuit to achieve the purpose of real-time observation of the hot resin in the lower cylinder body 62.

[0014] The bottom of the injection tube 50 is configured as a sealing structure, and a discharge hole is provided in a ring shape at the bottom of the injection tube 50. The hot resin flowing in the injection tube 50 will not flow out from the discharge hole when not under pressure, thereby avoiding the problem of hot resin in the injection tube 50 dripping during non-injection molding operations.

[0015] The lower part of the piston 52 is placed in the metal telescopic sleeve 63. The diameter of the piston 52 is 2-5 cm smaller than the inner diameter of the metal telescopic sleeve 63. The lower part of the piston 52 can guide the straightness of the metal telescopic sleeve 63 during telescopic movement. The bottom surface of the piston 52 is set to a spherical structure to facilitate the lower part of the piston 52 to be embedded and installed in the metal telescopic sleeve 63.

[0016] A guide sleeve 41 is fixedly installed on the lower mold 2, and the guide sleeve 41 is slidably installed on the support column 4. The accuracy of the inner hole of the guide sleeve 41 is easier to process than the accuracy of the inner hole of the lower mold 2. Through the guiding effect of the guide sleeve 41, the straightness of the lower mold 2 when moving up and down along the support column 4 can be improved.

[0017] The hot resin in a flowable state is injected into the lower cylinder 62 through the injection interface 55, and the first cylinder 51 drives the piston 52 and the metal telescopic sleeve 63 to shrink upward. The metal telescopic sleeve 63 is a sealed structure, and the hot resin in the lower cylinder 62 will not enter the metal telescopic sleeve 63, so as to increase the storage space of the hot resin in the lower cylinder 62. The semiconductor rectifier chip and the lead frame that have completed the lead bonding are placed on the lower mold 2, and the second cylinder 8 is started to push the lower mold 2 to move upward along the support column 4 until it is buckled with the upper mold 1. The central area of ​​the semiconductor rectifier chip and the lead frame that have completed the lead bonding is located in the plastic packaging mold cavity 101, and the edge of the lead frame is sealed. The seal is tightly fixed between the upper mold 1 and the lower mold 2, and the first cylinder 51 is started to press the piston 52 and the metal telescopic sleeve 63 downward. The metal telescopic sleeve 63 expands downward to squeeze the hot resin in the lower cylinder body 62 and inject it into the plastic sealing cavity 101 through the injection pipe 50 and the runner 12. The gas in the plastic sealing cavity 101 is discharged through the exhaust channel on the top of the upper mold 1. After the plastic sealing cavity 101 is filled with hot resin, the cooling water circulation pump is started to cool the hot resin in the upper mold 1, the lower mold 2, and the plastic sealing cavity 101 through the circulating cooling water pipe 9, thereby improving the plastic sealing efficiency. After the plastic sealing is cooled and formed, the piston rods of the first cylinder 51 and the first cylinder 8 are retracted to prepare for the next plastic sealing operation.

Claims

1. A semiconductor rectifier injection molding packaging device, characterized in that: The invention comprises an upper mold (1), a lower mold (2), a base (3), a support column (4), a protective cover (5), an injection pipe (50), a first cylinder (51), a piston (52), a sealing plate (54), an upper cylinder body (61), a lower cylinder body (62), a metal telescopic sleeve (63), an annular hanging frame (64), a connecting rod (7), a second cylinder (8) and a circulating cooling water pipe (9), wherein four support columns (4) are distributed in a rectangular shape and their upper and lower ends are respectively fixedly connected to the upper mold (1) and the base (3), the lower mold (2) is slidably mounted on the support columns (4), and the lower mold (2 ) cooperates with the upper mold (1) to form a plastic sealing mold cavity (101); the cylinder body of the second cylinder (8) is fixedly mounted on the base (3); the piston rod of the second cylinder (8) is fixedly connected to the lower mold (2); the protective cover (5) is fixedly mounted on the top of the upper mold (1); the cylinder body of the first cylinder (51) is fixedly mounted on the protective cover (5); the sealing plate (54) is fixedly mounted on the protective cover (5); the upper cylinder body (61) is fixedly mounted on the top of the protective cover (5); the bottom of the lower cylinder body (62) is sealed and fixedly connected to the sealing plate (54); the sealing plate (5 4) is provided with an injection interface (55) connected to the lower cylinder body (62), the top of the lower cylinder body (62) is screwed and sealed and fixedly connected to the bottom of the upper cylinder body (61), the annular hanging frame (64) is compressed and sealed and fixedly installed between the top of the lower cylinder body (62) and the bottom of the upper cylinder body (61), the top of the metal telescopic sleeve (63) is sealed and fixedly hung and installed at the bottom of the annular hanging frame (64), the piston (52) is slidably installed in the upper cylinder body (61), the bottom of the metal telescopic sleeve (63) is set as a sealing structure, and the bottom of the piston is connected to the metal through a connecting rod (7). The bottom of the telescopic sleeve (63) is fixedly connected, a groove (11) is provided at the center of the bottom of the upper mold (1), a support block (13) is fixedly installed in the groove (11), the injection pipe (50) is sealed and fixedly installed on the sealing plate (54), the upper mold (1), and the support block (13), the plastic sealing mold cavity (101) and the groove (11) are provided with a connected runner (12), the circulating cooling water pipe (9) is provided in the upper mold (1) and the lower mold (2), and the outer walls of the upper cylinder body (61) and the lower cylinder body (62) are both wound with electric heating wires.

2. The semiconductor rectifier injection molding packaging device according to claim 1, characterized in that: The bottom of the injection pipe (50) is provided with a sealing structure, and the bottom of the injection pipe (50) is provided with a discharge hole in a ring shape.

3. The semiconductor rectifier injection molding packaging device according to claim 1, characterized in that: The bottom surface of the piston (52) is configured as a spherical structure.

4. The semiconductor rectifier injection molding packaging device according to claim 1, characterized in that: A guide sleeve (41) is fixedly mounted on the lower mould (2), and the guide sleeve (41) is slidably mounted on the support column (4).

Images