Working method of BGA (ball grid array) molding die
The technical field is as follows:
The invention relates to the technical field of semiconductor packaging, in particular to a BGA (ball grid array) molding die.
background art:
in the MOLDING process of semiconductor packaging, due to the particularity of the substrate material, the control precision of part of the size of the substrates of different manufacturers and different types cannot meet the packaging requirement. The substrate is actually a PCB, and a plurality of sizes can only be about +/-0.1 mm. In the MOLDING process, as the minimum particles of the epoxy resin are smaller than the size, the plastic packaging material overflows, and the equipment cannot automatically operate.
The current measures are that the sizes of substrates of different batches are compensated and controlled by replacing an eccentric positioning pin, the gap is ensured to be smaller than the minimum particle of epoxy resin, and the equipment can automatically work. In the prior art, an eccentric pin positioning mode is adopted (refer to a technical document of a BGA molding die with application publication No. CN104552672A specifically), although in the positioning of the BGA molding die, the width of a needle point of an existing eccentric positioning pin can be changed and processed according to an installation needle hole of the positioning pin, the problem exists that the die needs to be disassembled and reassembled when the positioning pin is replaced every time, other problems caused by assembling errors exist while time is consumed, in addition, the processing requirement of the eccentric positioning pin is high, and the cost is high.
in order to solve the technical problem, the invention patent application with application publication number CN104552672A discloses a BGA molding die, which comprises a die holder, wherein a plurality of material cylinders are uniformly arranged in the middle of the die holder along a straight line, die boxes are arranged on two sides of the material cylinders, each die box is provided with a plurality of cavities uniformly arranged along a straight line, the arrangement direction of the cavities is the same as that of the material cylinders, a cavity strip is formed between every two adjacent cavities, a positioning block which slides towards the material cylinders is detachably and fixedly connected to the die boxes, a first positioning needle is inserted into the positioning block, and a second positioning needle is arranged on the cavity strip. According to the BGA molding die provided by the invention, the auxiliary positioning block is used for adjusting the position after the common round positioning pin is designed and installed, the BGA molding die is simple and quick, various problems possibly caused by repeated assembly of the die can be avoided, the BGA molding die is easy to process, simple in structure, free of occupying space, capable of adapting to the change of the size of a substrate in a certain range, simple to replace, stable in operation of equipment and low in cost, meanwhile, various unnecessary debugging and installation risks are reduced, and the production efficiency and the utilization efficiency of the equipment are greatly improved.
In the prior art, the cavity strip is designed to be micro-adjustable to meet the requirement of packaging of various BGA with micro-change in size, but the above technical scheme has certain problems: when the cavity strip is adjusted, one size of two adjacent cavities is increased and the other size is reduced, so that the packaging size of all BGA packages cannot be met.
The invention content is as follows:
the invention aims to overcome the defects in the prior art and provides a BGA molding die, wherein a pair of molding strips is designed, and each molding strip can be independently adjusted.
In order to achieve the purpose, the invention provides a BGA molding die, which comprises a die holder, wherein a plurality of charging barrels are longitudinally and uniformly distributed in the middle of the die holder, die boxes are arranged on the left side and the right side of each charging barrel, each die box comprises a longitudinally arranged inner side frame strip, a longitudinally arranged outer side frame strip, a transversely arranged first side frame strip and a transversely arranged second side frame strip, and the die boxes are isolated into a plurality of cavities through cavity forming strip modules; the inner frame strip is positioned at the side of the charging barrel, and the inner frame strip, the outer frame strip, the first frame strip and the second frame strip form a square frame-shaped total cavity; a plurality of longitudinal position adjusting devices are uniformly arranged in the outer frame strip of the cavity; the first side frame strip and the second side frame strip are respectively provided with a transverse position adjusting device;
a device guide groove which penetrates longitudinally is formed in the cavity outer frame strip; the inner side wall of the outer frame strip of the cavity is provided with a sliding chute, and the outer side wall of the outer frame strip of the cavity is provided with a gear mounting groove; the longitudinal position adjusting device comprises a moving body, an adjusting left unit and an adjusting right unit; the moving body is inserted into the inner cavity of the frame strip outside the cavity; the left adjusting unit and the right adjusting unit are symmetrically inserted into square grooves which are symmetrically distributed on the left and right of the moving body; the adjusting left unit and the adjusting right unit have the same structure; the left adjusting unit and the right adjusting unit respectively comprise a square convex part and a connecting part; the square convex part is movably inserted in the square groove; the square convex part is provided with a square cavity which is transparent left and right; a first rack and a second rack are arranged on two opposite side walls of the square cavity, the first rack is meshed with a first gear, the second rack is meshed with a second gear, the first gear is fixed on a first gear shaft, two ends of the first gear shaft are pivoted on the side walls of the square groove, the second gear is pivoted on a second gear shaft, and two ends of the second gear shaft are pivoted on the side walls of the square groove; a left-right screw rod is pivoted on the side wall of the square groove, the left-right screw rod is parallel to the first gear shaft and the second gear shaft, the left-right screw rod penetrates through the square cavity and comprises a left-right screw rod section and a right-right screw rod section, a left-handed nut is screwed on the left-right screw rod section, a right-handed nut is screwed on the right-handed screw rod section, a left friction block is fixed on the left-handed nut, a right friction block is fixed on the right-handed nut, the end part of the left friction block and the end part of the right friction block are movably sleeved on the second gear shaft, and the left friction block and the right friction block are positioned on two sides of the second gear;
The cavity molding strip module consists of two adjacent molding strips; one end of the forming strip is in sliding fit with the outer frame strip, the other end of the forming strip is in sliding fit with the inner frame strip, and the forming strip can move longitudinally along the outer frame strip and the inner frame strip; the connecting part of the left adjusting unit and the right adjusting unit extends out of the mounting cavity and is fixedly connected with the end part of the forming strip;
a third gear shaft is pivoted on the upper wall and the lower wall of the gear mounting groove on the outer side wall of the cavity outer frame strip; a third gear is horizontally fixed on the third gear shaft; a third rack is formed on the outer side wall of the moving body; the third gear is meshed with the third rack.
As a preferred option of the above technical solution, one end of the outer frame strip is in sliding fit with the first frame strip, and the other end of the outer frame strip is in sliding fit with the second frame strip; the structure of the transverse position adjusting device is the same as that of the left adjusting unit and the right adjusting unit, and the connecting part of the transverse position adjusting device is horizontally arranged; one end of the outer frame strip is fixedly connected with the connecting part of the transverse position adjusting device in the first frame strip; the other end of the outer frame strip is fixedly connected with the connecting part of the transverse position adjusting device of the second frame strip.
preferably, the connecting part comprises a sliding block and a connecting block arranged beside the sliding block, the square convex part is connected with the sliding block, and the forming strip is connected with the connecting block.
preferably, a first adjusting block is fixed at the end of the left-right screw rod, a second adjusting block is fixed at the end of the first gear shaft, and a straight-line-shaped groove is formed in each of the first adjusting block and the second adjusting block; the outer frame strip is provided with a first adjusting hole and a second adjusting hole which are communicated with the guide groove of the device, the first adjusting block is positioned at the bottom of the first adjusting hole, and the second adjusting block is positioned at the bottom of the second adjusting hole.
Preferably, a third adjusting block is fixed at the end of the third gear shaft, and the third adjusting block is provided with a straight groove; and a third adjusting hole communicated with the gear mounting groove is formed in the outer frame strip, and the third adjusting block is positioned at the bottom of the third adjusting hole.
the invention has the beneficial effects that: the longitudinal position adjusting device comprises a left adjusting unit and a right adjusting unit, and the positions of the two molding strips can be independently adjusted to meet the small change of the size of the substrate in each mold box cavity.
description of the drawings:
FIG. 1 is a schematic structural diagram of a BGA molding die of the present invention;
FIG. 2 is a schematic view of the BGA molding die of FIG. 1, shown in partial cross-section;
FIG. 3 is an enlarged view of FIG. 1 at C;
FIG. 4 is an enlarged view of FIG. 2 at B;
fig. 5 is a schematic structural view of the longitudinal position adjusting device 10 according to the present invention;
FIG. 6 is a schematic view of the longitudinal position adjustment device 10 of FIG. 5, partially in section;
FIG. 7 is a top view of FIG. 5;
FIG. 8 is a schematic view of the longitudinal position adjustment device 10 of FIG. 7, partially in section;
FIG. 9 is an enlarged view taken at A in FIG. 8;
In the figure, 10, a moving body; 101. a square groove; 102. a left-right screw rod; 1021. a first adjusting block; 103. a left friction block; 104. a right friction block; 11. adjusting the left unit; 110. a connecting portion; 1101. a slider; 1102. connecting blocks; 111. a square convex part; 112. a square chamber; 113. a first rack; 114. a second rack; 115. a first gear; 116. a second gear; 117. a first gear shaft; 1171. a second adjusting block; 118. a second gear shaft; 12. adjusting the right unit; 20. a die holder; 30. a charging barrel; 40. a mold box; 41. inner frame strips; 42. a cavity outer frame strip; 4201. a first adjustment hole; 4202. a second adjustment hole; 426. a chute; 427. a device guide groove; 4281. a third rack; 4282. a third gear; 4283. a third gear shaft; 4284. a third adjustment hole; 4285. a third adjusting block; 429. a gear mounting groove; 43. a first side frame strip; 44. a second frame strip; 45. a cavity molding strip module; 451. forming a strip; 51. a lateral position adjusting device.
the specific implementation mode is as follows:
as shown in fig. 1 and 2, a BGA molding die comprises a die holder 20, a plurality of material cylinders 30 are uniformly arranged in the middle of the die holder in the longitudinal direction, a die box 40 is disposed on the left and right sides of the material cylinders 30, the die box 40 includes an inner frame strip 41 disposed in the longitudinal direction, an outer frame strip 42 disposed in the longitudinal direction, a first frame strip 43 disposed in the transverse direction, and a second frame strip 44 disposed in the transverse direction, and the die box 40 is separated into a plurality of cavities 401 by a cavity forming strip module 45; the inner frame strip 41 is located at the side of the charging barrel 30, and the inner frame strip 41, the outer frame strip 42, the first frame strip 43 and the second frame strip 44 form a square frame-shaped overall cavity; a plurality of longitudinal position adjusting devices are uniformly arranged in the cavity outer frame strip 42; the first side frame strip 43 and the second side frame strip 44 are symmetrically provided with transverse position adjusting devices 51;
As shown in fig. 4 and 6, a device guide groove 427 longitudinally penetrating is formed in the cavity outer frame strip 42; the inner side wall of the cavity outer frame strip 42 is provided with a sliding groove 426, and the outer side wall is provided with a gear mounting groove 429; the longitudinal position adjusting device comprises a moving body 10, an adjusting left unit 11 and an adjusting right unit 12; the moving body 10 is inserted into the inner cavity of the outer frame strip 42 of the cavity; the left adjusting unit and the right adjusting unit are symmetrically inserted into the square grooves 101 which are symmetrically distributed on the left and right of the moving body 10; the adjusting left unit and the adjusting right unit have the same structure; the left adjusting unit and the right adjusting unit respectively comprise a square convex part 111 and a connecting part 110; the square convex part 111 is movably inserted in the square groove 101; the square convex part 111 is provided with a square cavity 112 which is through from left to right; a first rack 113 and a second rack 114 are arranged on two opposite side walls of the square chamber, the first rack 113 is meshed with a first gear 115, the second rack 114 is meshed with a second gear 116, the first gear is fixed on a first gear shaft 117, two ends of the first gear shaft 117 are pivoted on the side wall of the square groove, the second gear 116 is pivoted on a second gear shaft 118, and two ends of the second gear shaft 118 are pivoted on the side wall of the square groove 101; a left-right screw rod 102 is pivoted on the side wall of the square groove 101, the left-right screw rod 102 is parallel to a first gear shaft 117 and a second gear shaft 118, the left-right screw rod 102 penetrates through the square chamber 112, the left-right screw rod 102 comprises a left-right screw rod section and a right-right screw rod section, a left-hand nut is screwed on the left-hand screw rod section, a right-hand nut is screwed on the right-hand screw rod section, a left friction block 103 is fixed on the left-hand nut, a right friction block 104 is fixed on the right-hand nut, the end part of the left friction block 103 and the end part of the right friction block 104 are movably sleeved on the second gear shaft 118, and the left friction block 103 and the right friction block 104 are positioned on two sides of the;
As shown in fig. 2 and 4, the cavity molding strip module 45 is composed of two adjacent molding strips 451; one end of the molding strip 451 is in sliding fit with the outer frame strip 42, the other end of the molding strip 451 is in sliding fit with the inner frame strip 41, and the molding strip 451 can move longitudinally along the outer frame strip 42 and the inner frame strip 41; the connecting part 110 of the left adjusting unit and the right adjusting unit extends out of the mounting cavity and is fixedly connected with the end part of the molding strip 451;
as shown in fig. 2 and 4, a third gear shaft 4283 is pivotally connected to the upper and lower walls of the gear mounting groove 429 on the outer side wall of the cavity outer frame strip 42; a third gear 4282 is horizontally fixed on the third gear shaft 4283; a third rack 4281 is formed on the outer side wall of the moving body 10; third gear 4282 meshes with third rack 4281.
As shown in fig. 2 and 6; one end of the outer frame strip 42 is in sliding fit with the first frame strip 43, and the other end of the outer frame strip 42 is in sliding fit with the second frame strip 44; the structure of the transverse position adjusting device is the same as that of the left adjusting unit and the right adjusting unit, and the connecting part 110 of the transverse position adjusting device is horizontally arranged; one end of the outer frame strip 42 is fixedly connected with the connecting part 110 of the transverse position adjusting device in the first frame strip 43; the other end of the outer frame strip 42 is fixedly connected to the connecting portion 110 of the lateral position adjusting device of the second frame strip 44.
as shown in fig. 5 and 7, the connecting portion 110 includes a slider 1101 and a connecting block 1102 provided beside the slider, the square protrusion 111 is connected to the slider, and the molding strip 451 is connected to the connecting block 1102.
As shown in fig. 3 and 6, a first adjusting block 1021 is fixed at an end of the left-right screw rod 102, a second adjusting block 1171 is fixed at an end of the first gear shaft 117, and a "straight" groove is formed in each of the first adjusting block 1021 and the second adjusting block 1171; the outer frame strip 42 is opened with a first adjusting hole 4201 and a second adjusting hole 4202 communicating with the device guide groove 427, the first adjusting block 4201 is located at the bottom of the first adjusting hole 4201, and the second adjusting block 1171 is located at the bottom of the second adjusting hole 4202.
As shown in fig. 3, a third adjusting block 4285 is fixed at an end of the third gear shaft 4283, and the third adjusting block 4285 is provided with a straight groove; the outer frame strip 42 is provided with a third adjusting hole 4284 communicated with the gear mounting groove 429, and the third adjusting block 4285 is positioned at the bottom of the third adjusting hole 4284.
In the specific operation, the working process of adjusting the BGA molding die to the position of the molding strip is as follows:
firstly, the third gear shaft 4283 is rotated to drive the third gear 4282, the third gear 4282 drives the third rack 4281, and the third rack 4281 is driven to drive the moving body 10 to move integrally;
second, the adjustment left unit 11 and the adjustment right unit 12 are operated: rotating the left-right screw rod 102 to make the left friction block 103 and the right friction block 104 separated from the contact with the second gear 116; rotating the first gear shaft 117, the first gear shaft 117 drives the first gear 115 to rotate, the first gear 115 drives the first rack 113 on one side wall of the square chamber 112 to extend outwards, the first rack 113 drives the square protrusion 111 to extend outwards in the square groove 101, and the square protrusion 111 drives the adjusting left unit 11 (adjusting right unit 12) to move in the installation cavity, so that the moving body drives the forming strip 451 to make a slight longitudinal movement along the outer frame strip 42 and the inner frame strip 41 through the connecting part 110; at the same time, the second rack 114 on the other side wall of the square chamber 112 descends, and the second rack 114 drives the second gear 116 to rotate around the second gear shaft 118;
Thirdly, when the molding strip 451 moves longitudinally to a preset position, the left-handed screw rod 102 is rotated, the left-handed nut and the right-handed nut respectively drive the left friction block 103 and the right friction block 104 to clamp the second gear 116, so as to lock the second gear 116, the second gear 114 is locked by the locking of the second gear 116, the square convex part 111 is positioned in the square groove 101 by the locking of the second gear 114, and the position of the molding strip 451 is kept stable.
the above description is only a preferred embodiment of the present invention, and for those skilled in the art, the present invention should not be limited by the description herein, since various changes and modifications can be made in the details of the embodiment and the application range according to the spirit of the present invention.