CN216858733U - Removable welding jig - Google Patents

Abstract

The application discloses removable welding jig is applicable to the different power module of welding, belongs to power module encapsulation field. The jig comprises: the upper cover plate is connected with the lower cover plate through a fastener, a middle plate groove, a first positioning hole and a device positioning hole are formed in the lower cover plate, a base plate groove is formed in the lower end face of the lower cover plate, and the base plate groove is communicated with the middle plate groove and is in a step shape; the middle plate is placed in the middle plate groove, and a chip positioning hole is formed in the middle plate; the bottom plate is arranged below the lower cover plate and penetrates through the first positioning hole and the second positioning hole through the positioning pin to be connected with the bottom plate. When the welding jig is used for welding the chips with different chip layouts, the welding jig does not need to be processed again, only the middle plate of the welding jig needs to be replaced, the time for customizing the welding jig is shortened, the operation is simple and convenient, and the economic cost is reduced.

Description

Removable welding jig

Technical Field

The application relates to a removable welding jig is applicable to the different power module of welding, belongs to power module encapsulation field.

Background

Reflow soldering is an indispensable process flow in the electronic industry, and by providing a heating environment, soldering lugs are heated and melted according to a proper temperature curve, and a power chip, a passive device and a copper layer on the surface of a copper-clad ceramic substrate (DBC) are reliably combined together to achieve the purpose of electrical interconnection, which is closely related to the quality of product packaging. The welding jig used at present has the problems of inaccurate chip positioning, insufficient welding of passive devices, easy deformation due to heating, high welding void ratio and the like, and reduces the yield of the power module.

Due to the fact that the current of the chip is large, the quality of the welding layer of the chip and the DBC determines the size of the current capacity and the heat dissipation capacity of the power module, and therefore the service life of the power module is determined. In the reflow soldering process, the traditional jig is relatively simple in design, bubbles exist in the solder during soldering, and if the bubbles cannot be removed in time, a large soldering voidage can be generated, and the service life of the module is reduced. Secondly, the traditional welding jig has poor processing precision, is not accurate enough for positioning the chip on the DBC, and influences subsequent bonding process operation. Meanwhile, due to the problem of material selection of the traditional welding jig, the traditional welding jig is easy to be heated and deformed, so that unnecessary mechanical damage is caused to the chip.

In addition, the conventional welding jig is usually designed to be only used for one power module, and after the subsequent power module is improved, the subsequent power module is discarded due to waste, so that waste is generated, and unnecessary economic loss is caused. For the welding jig with high processing precision, the problems of higher processing cost, longer design and processing time of the welding jig and the like exist.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, this application has provided a removable welding jig, has seted up the chip locating hole on the medium plate, and different medium plate designs correspond different chips and DBC overall arrangement, when the chip of welding different chip overall arrangements, need not to reprocess the welding jig, only need to change the medium plate of welding jig can, can be used for welding different power module, reduce the time of customization welding jig, easy operation is convenient, easily change, reduction economic cost.

According to an aspect of the present application, there is provided a replaceable welding jig, the jig including:

the upper cover plate and the lower cover plate are connected through a fastener, a middle plate groove, a first positioning hole and a device positioning hole are formed in the lower cover plate, a substrate groove is formed in the lower end face of the lower cover plate, and the substrate groove is communicated with the middle plate groove and is in a step shape;

the middle plate is placed in the middle plate groove, and a chip positioning hole is formed in the middle plate;

the bottom plate is arranged below the lower cover plate and penetrates through the first positioning hole and the second positioning hole through positioning pins to be connected with the bottom plate.

Optionally, a support lug is arranged on the periphery of the middle plate, a support groove is formed in the upper end face of the lower cover plate, and the support lug is clamped with the support groove, so that the middle plate is fixed in the middle plate groove.

Optionally, the number of the support lugs is at least two, and the support lugs are uniformly arranged on the periphery of the middle plate, preferably, the middle plate is rectangular, and each side surface of the middle plate is provided with at least one support lug.

Optionally, the ratio of the thickness of the support lug to the thickness of the middle plate is 1: 3-5.

Optionally, the chip positioning hole includes an upper chip positioning hole and a lower chip positioning hole which are communicated with each other, the upper chip positioning hole is circular and used for placing the first pressing block, and the lower chip positioning hole is rectangular and used for placing the chip.

Optionally, the device positioning hole includes an upper device positioning hole and a lower device positioning hole that are communicated, the upper device positioning hole is circular and used for placing the second pressing block, and the lower device positioning hole is rectangular and used for placing the passive device.

Optionally, the first pressing block includes a first upper pressing block and a first lower pressing block, a diameter of the first upper pressing block is larger than diameters of the first lower pressing block and the upper chip positioning hole, the first lower pressing block is placed in the upper chip positioning hole, and a height of the first lower pressing block is not smaller than a height of the upper chip positioning hole.

Optionally, the second pressing block includes a second upper pressing block and a second lower pressing block, the diameter of the second upper pressing block is larger than the diameter of the second lower pressing block and the diameter of the upper device positioning hole, the second lower pressing block is placed in the upper device positioning hole, and the height of the second lower pressing block is larger than the height of the upper device positioning hole.

Optionally, a first release hole is formed in the circumferential direction of the lower chip positioning hole, a second release hole is formed in the circumferential direction of the lower device positioning hole, and a third release hole is formed in the circumferential direction of the substrate groove.

Preferably, the first release hole is arranged at a corner of the lower chip positioning hole, and the first release hole is semicircular.

Preferably, the second release hole is disposed at a corner of the lower device positioning hole, and the second release hole is semicircular.

Preferably, the third release holes are formed at corners of the substrate groove, and the third release holes are semicircular.

Optionally, the lower surface of the upper cover plate is provided with a first transition hole and a second transition hole, the depth of the first transition hole is larger than the height of the first upper pressing block for fixing the first upper pressing block, and the depth of the second transition hole is larger than the height of the second upper pressing block for fixing the second upper pressing block.

Preferably, the first transition hole and the first upper pressing block are circular, the diameter of the first transition hole is not smaller than that of the first upper pressing block, and more preferably, the ratio of the diameter of the first transition hole to the diameter of the first upper pressing block is 1.01-1.1: 1.

Preferably, the second transition hole and the second upper pressing block are circular, the diameter of the second transition hole is not smaller than that of the second upper pressing block, and more preferably, the ratio of the diameter of the second transition hole to the diameter of the second upper pressing block is 1.01-1.1: 1.

Optionally, the positioning pins include an upper positioning pin and a lower positioning pin, the diameter of the upper positioning pin is larger than the diameter of the first positioning hole and the diameter of the lower positioning pin, and the lower positioning pin is used for connecting the lower cover plate and the bottom plate.

Optionally, a third transition hole is formed in the lower surface of the upper cover plate, and the depth of the third transition hole is larger than the height of the upper positioning pin and used for fixing the upper positioning pin.

Preferably, the third transition hole and the upper positioning pin are circular, the diameter of the third transition hole is smaller than that of the upper positioning pin, and more preferably, the ratio of the diameter of the third transition hole to the diameter of the upper positioning pin is 1.01-1.1: 1.

Optionally, an observation hole is formed in the upper surface of the upper cover plate, and the observation hole is disposed above the device positioning hole and the chip positioning hole.

Optionally, rib plates are arranged on two sides of the bottom plate, and the rib plates are clamped with the edge of the lower cover plate.

Optionally, third positioning holes are formed in the periphery of the upper cover plate, fourth positioning holes are formed in the periphery of the lower cover plate, fifth positioning holes are formed in the periphery of the bottom plate, and the fastening piece penetrates through the third positioning holes, the fourth positioning holes and the fifth positioning holes to connect the upper cover plate, the lower cover plate and the bottom plate.

Optionally, the inner surfaces of the third positioning hole, the fourth positioning hole and the fifth positioning hole are provided with internal threads, the periphery of the fastener is provided with external threads, and the upper cover plate, the lower cover plate and the bottom plate are connected through bolts.

Benefits that can be produced by the present application include, but are not limited to:

1. the application provides a removable welding jig, when the chip of welding different chip overall arrangement, need not to reprocess welding jig, only need change welding jig's medium plate can, reduce the time of customization welding jig, easy operation is convenient, easily changes, reduces economic cost.

2. The application provides a removable welding jig, through the design of journal stirrup and support groove, be convenient for take off the medium plate from apron down or put back, support the groove simultaneously and provide holding power and positioning action for the medium plate, can guarantee that medium plate and apron closely cooperate down, avoid the landing to appear in the medium plate when the welding, and then improve the steadiness and the positioning accuracy of chip on the base plate, be convenient for carry on subsequent welding operation.

3. The application provides a removable welding jig, first briquetting and second briquetting are used for compacting chip and passive device when the welding, improve the positioning accuracy of chip and passive device, thereby make chip and passive device and molten condition's soldering lug fully contact, reduce the production of bubble, effectively reduce the void ratio of chip and avoid passive device rosin joint, and can prevent chip and passive device to take place to stick up or slope when the welding, improve power module's welding layer quality, prolong power module's life.

4. The application provides a removable welding jig, the setting in first release hole, second release hole and third release hole can be for providing the deformation space of chip, passive device and base plate, prevents that the welding jig from damaging chip, passive device and covering copper ceramic substrate because of thermal deformation, also is convenient for take off welding base plate as an organic whole, chip and passive device simultaneously.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

fig. 1 is a schematic perspective view of a welding jig according to an embodiment of the present application;

fig. 2 is a schematic perspective view of an upper cover plate according to an embodiment of the present application, the view angle being a top view;

fig. 3 is a schematic perspective view of an upper cover plate according to an embodiment of the present application, the view angle being a bottom view;

fig. 4 is a schematic perspective view of a middle plate according to an embodiment of the present application, the view angle being a top view;

FIG. 5 is a perspective view of the middle plate according to the embodiment of the present application, the view angle is a bottom view;

FIG. 6 is a schematic perspective view of a lower cover plate according to an embodiment of the present application, the view angle being from above;

FIG. 7 is a perspective view of a lower cover plate according to an embodiment of the present disclosure, the view angle being from below;

FIG. 8 is an enlarged view of a portion A of FIG. 7;

FIG. 9 is a schematic perspective view of a base plate according to an embodiment of the present application, the view from above;

FIG. 10 is a schematic perspective view of a base plate according to an embodiment of the present application, viewed from a bottom perspective;

FIG. 11 is a perspective view of an upper cover plate, a middle plate and a lower cover plate assembly according to an embodiment of the present disclosure, the view angle being from above;

FIG. 12 is a perspective view of the combination of the upper cover plate, the middle plate and the lower cover plate according to the embodiment of the present application, the view angle is a bottom view;

FIG. 13 is a perspective view of a first compact according to an embodiment of the present application;

FIG. 14 is a perspective view of a second compact according to an embodiment of the present application;

FIG. 15 is a schematic perspective view of a locating pin according to an embodiment of the present application;

list of parts and reference numerals:

10. an upper cover plate; 11. an observation hole; 12. a first transition hole; 13. a second transition hole; 14. a third transition hole; 15. a third positioning hole; 20. a middle plate; 21. chip positioning holes; 211. positioning holes of the upper chip; 212. a lower chip positioning hole; 213. a first release hole; 22. supporting a lug; 30. a lower cover plate; 31. a middle plate groove; 32. a first positioning hole; 33. a device positioning hole; 331. an upper device positioning hole; 332. a lower device positioning hole; 333. a second release hole; 34. a substrate recess; 341. a third release hole; 35. a support groove; 36. a fourth positioning hole; 40. a substrate; 50. a base plate; 51. a second positioning hole; 52. a fifth positioning hole; 53. a rib plate; 60. a bolt; 70. a first pressing block; 71. a first upper pressing block; 72. a first lower pressing block; 80. a second pressing block; 81. a second upper pressing block; 82. a second lower pressing block; 90. positioning pins; 91. an upper positioning pin; 92. and a lower positioning pin.

Detailed Description

In order to more clearly explain the overall concept of the present application, the following detailed description is given by way of example in conjunction with the accompanying drawings.

In order that the above objects, features and advantages of the present application can be more clearly understood, the present application will be described in further detail with reference to the accompanying drawings and detailed description. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, however, the present application may be practiced in other ways than those described herein, and therefore the scope of the present application is not limited by the specific embodiments disclosed below.

In addition, in the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships based on those shown in the drawings, are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. In the description herein, reference to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Referring to fig. 1-15, embodiments of the present application disclose a replaceable welding jig comprising: the upper cover plate 10 is connected with the lower cover plate 30 through a fastener, the lower cover plate 30 is provided with a middle plate groove 31, a first positioning hole 32 and a device positioning hole 33, the lower end surface of the lower cover plate 30 is provided with a substrate groove 34, and the substrate groove 34 is communicated with the middle plate groove 31 and is in a step shape; the middle plate 20, the middle plate 20 is placed in the middle plate groove 31, and the middle plate 20 is provided with a chip positioning hole 21; the bottom plate 50 is provided with a second positioning hole 51, the second positioning hole 51 is opposite to the first positioning hole 32, and the bottom plate 50 is arranged below the lower cover plate 30 and connected with the bottom plate 50 through a positioning pin 90 passing through the first positioning hole 32 and the second positioning hole 51.

When the welding jig is used, the chip positioning holes 21 are used for placing chips, the device positioning holes 33 are used for placing passive devices, the middle plate groove 31 in the lower cover plate 30 is clamped with the middle plate 20, the chip positioning holes 21 are formed in the middle plate 20, different chips and DBC layouts are designed and correspond to different middle plates 20, the middle plate 20 is used for fixing and positioning the chips, and the chips are prevented from being subjected to position deviation when being welded. When welding the chip of different chip overall arrangements, need not to reprocess the welding tool, only need change the welding tool the medium plate 20 can, the difference between different medium plates 20 lies in the position difference of chip locating hole 21, can be used for welding different power module, reduces the time of customization welding tool, and easy operation is convenient, easily changes, reduces economic cost. In addition, for the power module with special requirements, when the layout of the passive device on the substrate 40 needs to be adjusted, the lower cover plate 30 can be replaced, the difference between different lower cover plates 30 lies in that the positions of the device positioning holes 33 are different, and different middle plates 20 and lower cover plates 30 can be flexibly selected according to the power module produced actually through the designed lower cover plate 30 and middle plate 20, so that the customizing time of the welding jig is saved, the universality of the welding jig is improved, and the occupied space of the welding jig is reduced. In addition, the middle plate 20 is smaller in size, uses less material, and has lower overall economy and time cost compared to conventional welding jigs.

Specifically, the middle plate 20 is engaged with the middle plate groove 31, the shapes of the middle plate 20 and the middle plate groove 31 may be any shapes, for example, a triangle, a circle, a rectangle, etc., as long as the middle plate 20 can be engaged with the middle plate groove 31 to fix the middle plate 20, and preferably, when the middle plate 20 is engaged with the middle plate groove 31, the upper end surface of the middle plate 20 is flush with the upper end surface of the lower cover plate 30.

Specifically, the shape of the substrate recess 34 is designed according to the shape of the substrate 40 to be soldered, as long as the substrate 40 is securely engaged in the substrate recess 34, and when the substrate 40 is placed in the substrate recess 34, the lower surface of the substrate 40 is flush with the lower surface of the lower cover plate 30. More specifically, the substrate is a copper-clad ceramic substrate.

Specifically, the shapes of the chip positioning holes 21 and the device positioning holes 33 are not particularly limited to this, as long as the chips and the passive devices can be positioned, and they may be set according to the shapes of the chips and the passive devices to be soldered, such as a circle, a triangle, or a polygon.

As an embodiment, referring to fig. 4 to 6, the middle plate 20 is provided with a support lug 22 at the outer circumference thereof, the lower cover plate 30 is provided with a support groove 35 at the upper end surface thereof, and the support lug 22 is engaged with the support groove 35 so that the middle plate 20 is fixed in the middle plate groove 31. The support grooves 35 are close to the edge of the middle plate groove 31 and are the same as the middle plate groove 31, the positions of the support grooves 35 correspond to the positions of the support lugs 22, the heights of the support lugs 22 are equal to the heights of the support grooves 35, through the design of the support lugs 22 and the support grooves 35, the middle plate 20 can be conveniently taken down from or placed back on the lower cover plate 30, meanwhile, the support grooves 35 provide support force and positioning effect for the middle plate 20, the middle plate 20 and the lower cover plate 30 can be guaranteed to be tightly matched, the middle plate 20 is prevented from sliding down during welding, the stability and the positioning accuracy of a chip on the substrate 40 are further improved, and subsequent welding operation is facilitated. Preferably, the lugs 22 are designed to have a uniform standard size so that different subsequent middle plates 20 can be freely replaced in the lower cover plate 30.

As an embodiment, the number of the support lugs 22 is at least two, and the support lugs 22 are uniformly arranged on the periphery of the middle plate 20, so that the stability of the engagement between the middle plate 20 and the middle plate groove 31 can be further ensured under the arrangement, preferably, the middle plate 20 is rectangular, at least one support lug 22 is arranged on each side surface of the middle plate 20, and the middle plates 20 are uniformly rectangular, so that the forming processing of the middle plates 20 and the middle plate groove 31 is facilitated.

Optionally, the ratio of the thickness of the support lug 22 to the thickness of the middle plate 20 is 1: 3-5. The thickness ratio of the arrangement is not only beneficial to the processing of the middle plate 20 and the middle plate groove 31, but also can ensure that the supporting groove 35 of the lower cover plate 30 plays a role in stably supporting and positioning the middle plate 20. Specifically, the length and width of the support lug 22 can be adjusted according to actual needs in production, and the support lug 22 is not particularly limited as long as the support lugs 22 of different middle plates 20 are uniform in size.

As an embodiment, the chip positioning hole 21 includes an upper chip positioning hole 211 and a lower chip positioning hole 212 communicating with each other, the upper chip positioning hole 211 is circular for placing the first pressing block 70, and the lower chip positioning hole 212 is rectangular for placing the chip. Divide into two parts with chip locating hole 21, go up chip locating hole 211 and be used for placing first briquetting 70, first briquetting 70 is used for the compaction chip when the welding, improve the positioning accuracy of chip, thereby make the chip fully contact with the soldering lug of molten condition, reduce the production of bubble, with the chip bonding on base plate 40, effectively reduce the void ratio of chip, and first briquetting 70 can prevent the chip to take place to stick up or the slope when the welding, improve power module's welding layer quality, prolong power module's life.

Specifically, the shape of the first pressing block 70 is not specifically limited, and may be a cylinder, a truncated cone, a rectangle, or a square, as long as it is ensured that the first pressing block 70 can be placed in the upper chip positioning hole 211. Preferably, in order to improve the stability of the first pressing piece 70 in the upper chip positioning hole 211, the first pressing piece 70 is cylindrical in shape.

As an embodiment, referring to fig. 13, first pressing block 70 includes first upper pressing block 71 and first lower pressing block 72, the diameter of first upper pressing block 71 is larger than the diameter of first lower pressing block 72 and upper chip positioning hole 211, first lower pressing block 72 is placed in upper chip positioning hole 211, and the height of first lower pressing block 72 is not smaller than the height of upper chip positioning hole 211. Under this mode of setting, when first briquetting 72 was placed in last chip locating hole 211, first briquetting 72 can rely on the gravity compaction chip of self, and first briquetting 71 is located the top of last chip locating hole 211, is convenient for take out or put down holistic first briquetting 70 in last chip locating hole 211, improves this welding jig's the simple operation nature.

Similarly, as an embodiment, the device positioning holes 33 include an upper device positioning hole 331 and a lower device positioning hole 332 which are communicated with each other, the upper device positioning hole 331 is circular for placing the second pressing block 80, and the lower device positioning hole 332 is rectangular for placing the passive device. Under this setting, second briquetting 80 is used for the compaction passive device when the welding, improves the positioning accuracy of passive device to make passive device and soldering lug fully contact, reduce the welding hole rate, and avoid passive device rosin joint, improve power module's welding quality.

Specifically, the shape of the second pressing block 80 is not particularly limited, and may be cylindrical, truncated cone, rectangular or square, as long as the second pressing block 80 can be placed in the upper device positioning hole 331. Preferably, in order to improve the stability of the second pressing piece 80 in the upper device positioning hole 331, the second pressing piece 80 is cylindrical in shape.

As an embodiment, referring to fig. 14, the second pressing block 80 includes a second upper pressing block 81 and a second lower pressing block 82, the diameter of the second upper pressing block 81 is larger than the diameter of the second lower pressing block 82 and the upper device positioning hole 331, the second lower pressing block 82 is placed in the upper device positioning hole 331, and the height of the second lower pressing block 82 is larger than the height of the upper device positioning hole 331. Similarly, the second pressing block 82 can compact the passive device, so that the second pressing block 80 can be conveniently taken and placed, and the operation convenience is improved.

As an embodiment, referring to fig. 5, the lower chip positioning hole 212 is provided with a first release hole 213 in a circumferential direction, and referring to fig. 7 to 8, the lower device positioning hole 332 is provided with a second release hole 333 in a circumferential direction, and the substrate recess 34 is provided with a third release hole 341 in a circumferential direction. The first release hole 213, the second release hole 333, and the third release hole 341 are arranged to provide a deformation space for the chip, the passive device, and the substrate 40, so as to prevent the chip, the passive device, and the substrate 40 from being damaged by the welding jig due to thermal deformation, and after the welding is completed, the substrate 40, the chip, and the passive device can be conveniently taken down.

As an embodiment, the first release hole 213 is disposed at a corner of the lower chip positioning hole 212, the second release hole 333 is disposed at a corner of the lower device positioning hole 332, the third release hole 341 is disposed at a corner of the substrate recess 34, and the first release hole 213, the second release hole 333, and the third release hole 341 are semicircular. Preferably, the four corners of the lower chip positioning hole 212, the lower device positioning hole 332 and the substrate groove 34 are respectively provided with a first release hole 213, a second release hole 333 and a third release hole 341, which facilitates the molding process, further reduces the damage of the chip, the passive device and the substrate 40 during the soldering process, and improves the process yield.

As an embodiment, referring to fig. 15, the positioning pins 90 include an upper positioning pin 91 and a lower positioning pin 92, the upper positioning pin 91 having a diameter larger than the first positioning hole 32 and the lower positioning pin 92, and the lower positioning pin for connecting the lower cover plate 30 and the base plate 50. Specifically, the positioning pin 90, the first positioning hole 32, and the second positioning hole 51 may have the same shape, and may be triangular, circular, or polygonal, preferably circular. The diameter of first locating hole 32 is not less than the diameter of second locating hole 51, and lower locating pin 92 passes first locating hole 32 and second locating hole 51 to be connected bottom plate 50 and lower apron 30 block, the setting of going up locating pin 91 then is favorable to taking out lower locating pin 92, is convenient for dismantle bottom plate 50 and lower apron 30, saves this welding jig's assemble duration.

As an embodiment, referring to fig. 3, the lower surface of the upper cover plate 10 is provided with a first transition hole 12, a second transition hole 13 and a third transition hole 14, the depth of the first transition hole 12 is greater than the height of the first upper pressing block 71 for fixing the first upper pressing block 71, the depth of the second transition hole 13 is greater than the height of the second upper pressing block 81 for fixing the second upper pressing block 81, and the depth of the third transition hole 14 is greater than the height of the upper positioning pin 91 for fixing the upper positioning pin 91. When assembling this welding jig, generally earlier with upper cover plate 10, first briquetting 70, second briquetting 80, locating pin 90, well board 20 and apron 30 are assembled to the middleware down, carry out the chip after putting the middleware that will assemble upside down, passive device, placing of soldering lug and base plate 40, so first transition hole 12, the setting in second transition hole 13 and third transition hole 14 can be for first briquetting 70, second briquetting 80 and locating pin 90 provide the activity space, also play the location restriction effect to first briquetting 70 simultaneously, second briquetting 80 and locating pin 90, avoid it to rock in putting upside down, and then improve the positioning accuracy of chip and passive device.

In a preferred embodiment, the first transition hole 12 and the first upper pressing piece 71 are circular, the diameter of the first transition hole 12 is not smaller than that of the first upper pressing piece 71, the second transition hole 13 and the second upper pressing piece 81 are circular, the diameter of the second transition hole 13 is not smaller than that of the second upper pressing piece 81, the diameter of the third transition hole 14 and the upper positioning pin 91 are circular, and the diameter of the third transition hole 14 is smaller than that of the upper positioning pin 91. More preferably, the ratio of the diameter of the first transition hole 12 to the diameter of the first upper compact 71 is 1.01 to 1.1: 1. The ratio of the diameter of the second transition hole 13 to the diameter of the second upper pressing block 81 is 1.01-1.1: 1. The ratio of the diameter of the third transition hole 14 to the diameter of the upper positioning pin 91 is 1.01-1.1: 1.

As an embodiment, referring to fig. 2, the upper surface of the upper cover plate 10 is opened with a viewing hole 11, and the viewing hole 11 is disposed above the device positioning hole 33, the chip positioning hole 21, and the first positioning hole 32. The observation hole 11 that sets up is used for observing first briquetting 70, second briquetting 80 and locating pin 90's position, judges whether first briquetting 70 and second briquetting 80 are abundant compaction chip and passive device to make chip, passive device and soldering lug well contact, effectively reduced the voidage of chip and avoid passive device rosin joint. In addition, the thermocouple can measure the temperature of the first pressing block 70 and the second pressing block 80 through the observation hole 11, and monitor the temperature distribution of the welding jig in real time.

As an embodiment, referring to fig. 9 and 10, ribs 53 are provided on both sides of the bottom plate 50, and the ribs 53 are engaged with the edge of the lower cover plate 30. The rib 53 can prevent the lower cover plate 30 from moving on the bottom plate 50, and the stability of the welding jig is improved.

In one embodiment, the upper cover plate 10, the middle plate 20, the lower cover plate 30 and the bottom plate 50 are made of graphite material. Preferably, the graphite surface is subjected to high-temperature coating treatment, and the coating material is any one or more of titanium nitride, silicon nitride and titanium carbide. The material of above-mentioned welding jig can guarantee when the welding, reduces the deformability of welding jig spare part itself, reduces the damage to the chip, and graphite material is heated evenly simultaneously, improves the homogeneity of being heated of each position department when welding, and then improves welded planarization. The welding jig after high-temperature coating can reduce impurities on the surface of the graphite material, and improves the cleanliness and the finished product quality of the power module.

In one embodiment, the first pressing piece 70, the second pressing piece 80 and the positioning pin 90 are made of stainless steel, so that the positions of the two pressing pieces can be observed through the observation hole 11.

As an embodiment, referring to fig. 1, a third positioning hole 15 is formed around the upper cover plate 10, a fourth positioning hole 36 is formed around the lower cover plate 30, a fifth positioning hole 52 is formed around the base plate 50, and a fastening member passes through the third positioning hole 15, the fourth positioning hole 36 and the fifth positioning hole 52 to connect the upper cover plate 10, the lower cover plate 30 and the base plate 50. Preferably, the third positioning hole 15, the fourth positioning hole 36 and the fifth positioning hole 52 are internally threaded on the inner surface thereof, the fastener is externally threaded on the outer circumference thereof, and the upper cover plate 10, the lower cover plate 30 and the base plate 50 are connected by bolts 60. The upper cover plate 10, the lower cover plate 30 and the bottom plate 50 are connected into a whole through the bolts 60, so that the mounting and dismounting time of the welding jig is saved, the production cost is reduced, and the power module assembling and disassembling device is suitable for mass production of power modules. Preferably, a truncated cone is arranged above the third positioning hole 15, and is used for placing the bolt 60 to deviate, so that the tight fit between the upper cover plate 10 and the lower cover plate 30 is ensured.

The use method of the welding jig comprises the following steps: first, the support lugs 22 of the middle plate 20 are matched with the support grooves 35, so that the middle plate 20 is clamped on the lower cover plate 30, then the first pressing block 70, the second pressing block 80 and the positioning pins 90 are respectively arranged in the upper chip positioning hole 211, the upper device positioning hole 331 and the first positioning hole 32, the upper cover plate 10 is covered, the bolt 60 penetrates through the third positioning hole 15 and the fourth positioning hole 36, and the upper cover plate 10 and the lower cover plate 30 are combined together, wherein the combined state is shown in fig. 11 and 12; the upper cover plate 10 and the lower cover plate 30 are placed upside down, the substrate groove 34 is placed upwards at the moment, the chip and the passive device are respectively pasted on the lower chip positioning hole 212 and the lower device positioning hole 332 by using a vacuum suction pen, then the soldering lug is placed on the chip and the passive device by using the vacuum suction pen, and then the substrate 40 is placed in the substrate groove 34 to be clamped, because the upper cover plate 10 and the lower cover plate 30 are placed upside down, the front side of the chip, the passive device and the substrate 40 are downward, and the back side of the chip, the passive device and the substrate 40 are upward; and then, clamping and positioning the second positioning hole 51 of the bottom plate 50 and the positioning pin 90, and then, penetrating the fifth positioning hole 52 by using the bolt 60, so as to fixedly connect the bottom plate 50 and the lower cover plate 30, rightly placing the welding jig, observing whether the positions of the first pressing block 70, the second pressing block 80 and the positioning pin 90 deviate or not through the observation hole 11, and after confirming that no error exists, placing the welding jig into a reflow furnace for reflow soldering.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims (10)

1. The utility model provides a removable welding jig which characterized in that includes:

the upper cover plate and the lower cover plate are connected through a fastener, a middle plate groove, a first positioning hole and a device positioning hole are formed in the lower cover plate, a substrate groove is formed in the lower end face of the lower cover plate, and the substrate groove is communicated with the middle plate groove and is in a step shape;

the middle plate is placed in the middle plate groove, and a chip positioning hole is formed in the middle plate;

the bottom plate is arranged below the lower cover plate and penetrates through the first positioning hole and the second positioning hole through positioning pins to be connected with the bottom plate.

2. The replaceable welding jig of claim 1, wherein a support lug is disposed on the outer periphery of the middle plate, a support groove is disposed on the upper end surface of the lower cover plate, and the support lug is engaged with the support groove, so that the middle plate is fixed in the middle plate groove.

3. The replaceable welding jig of claim 2, wherein the ratio of the thickness of the support lug to the thickness of the middle plate is 1: 3-5.

4. The replaceable welding jig of claim 1, wherein the chip positioning holes comprise an upper chip positioning hole and a lower chip positioning hole which are communicated, the upper chip positioning hole is circular and used for placing the first pressing block, and the lower chip positioning hole is rectangular and used for placing a chip; and/or

The device positioning hole comprises an upper device positioning hole and a lower device positioning hole which are communicated, the upper device positioning hole is circular and used for placing a second pressing block, and the lower device positioning hole is rectangular and used for placing a passive device.

5. The replaceable welding jig of claim 4, wherein the first press block comprises a first upper press block and a first lower press block, the first upper press block has a diameter larger than the first lower press block and the upper die locating hole, the first lower press block is placed in the upper die locating hole, and the first lower press block has a height larger than the upper die locating hole;

the second pressing block comprises a second upper pressing block and a second lower pressing block, the diameter of the second upper pressing block is larger than the diameter of the second lower pressing block and the diameter of the upper device positioning hole, the second lower pressing block is placed in the upper device positioning hole, and the height of the second lower pressing block is not smaller than the height of the upper device positioning hole.

6. The replaceable welding jig as claimed in claim 5, wherein a first release hole is formed in the circumferential direction of the lower chip positioning hole, a second release hole is formed in the circumferential direction of the lower device positioning hole, and a third release hole is formed in the circumferential direction of the substrate groove;

the lower surface of the upper cover plate is provided with a first transition hole and a second transition hole, the depth of the first transition hole is larger than the height of the first upper pressing block and used for fixing the first upper pressing block, and the depth of the second transition hole is larger than the height of the second upper pressing block and used for fixing the second upper pressing block.

7. The replaceable welding jig of any one of claims 1 to 6, wherein the positioning pins comprise an upper positioning pin and a lower positioning pin, the diameter of the upper positioning pin is larger than the diameter of the first positioning hole and the diameter of the lower positioning pin, and the lower positioning pin is used for connecting the lower cover plate and the bottom plate.

8. The replaceable welding jig of claim 7, wherein the lower surface of the upper cover plate is provided with a third transition hole;

the depth of the third transition hole is larger than the height of the upper positioning pin, and the third transition hole is used for fixing the upper positioning pin.

9. The replaceable welding jig as claimed in any one of claims 1 to 6, wherein an observation hole is formed in the upper surface of the upper cover plate, and the observation hole is disposed above the device positioning hole and the chip positioning hole; and/or

Ribbed plates are arranged on two sides of the bottom plate and are clamped with the edge of the lower cover plate.

10. The replaceable welding jig as claimed in any one of claims 1 to 6, wherein a third positioning hole is formed around the upper cover plate, a fourth positioning hole is formed around the lower cover plate, a fifth positioning hole is formed around the base plate, and the fastener penetrates through the third positioning hole, the fourth positioning hole and the fifth positioning hole to connect the upper cover plate, the lower cover plate and the base plate.

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