Cutting-off jig and cutting-off equipment for welding test of power device packaging unit

Abstract

The utility model discloses a cutting jig and cutting equipment for a welding test of a power device packaging unit, the cutting jig comprises a bearing assembly, a lower die assembly, an upper die assembly and a guide assembly, the lower die assembly comprises a lower die main body, the upper surface of the lower die main body is provided with a first bearing part and a second bearing part which are used for bearing a connecting sheet, a cutting-off groove is formed in the cutting-off area corresponding to the power device packaging unit, the upper die assembly comprises an upper die connecting plate, a feeding channel penetrating through the abutting face is arranged on the discharging plate, and a cutter located in the feeding channel is installed on the upper die connecting plate. According to the scheme, deviation of the connecting piece and the welding position in the power device packaging unit in the cutting process is avoided, so that it is ensured that the fracture surface between the cut connecting piece and each assembly is smooth, layering does not occur at the joint, and a more accurate and real test object can be provided for subsequent combination test of each part.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging and testing technology, specifically to a cutting fixture and cutting equipment for welding and testing power device packaging units. Background Technology

[0002] MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) are power devices belonging to the field of semiconductor technology. Their chips are the core components of semiconductor devices, manufactured based on materials such as silicon (Si), silicon carbide (SiC), or gallium nitride (GaN). They focus on efficient power conversion and control, involving power switching and regulation in high-voltage, high-current scenarios, and are mainly used in consumer electronics, industrial control, automotive electronics, communication equipment, aerospace, and rail transportation, among other industries. Their biggest advantage lies in rapid turn-on / turn-off, reducing switching losses. With the explosive growth of new energy and electric vehicles, MOSFETs (especially wide-bandgap semiconductors such as SiC / GaN MOSFETs) are becoming core devices in future power electronic systems.

[0003] Due to the wide range of applications, especially in industrial control and automotive electronics, these products have stringent reliability requirements. Among these requirements, the bonding strength testing of each component after soldering is particularly important during the packaging process. Accurately obtaining the bonding strength data can effectively prevent product functional failures and reliability verification failures caused by poor soldering. Currently, during the assembly and soldering of this product, the positions of the PADs and clips on the chip need to be precisely positioned. Therefore, the product design incorporates limiting structures and soldering positioning on the tail of the clips and the frame.

[0004] The power device packaging unit, which employs limiting structures and welding positioning on the tail of the clip and frame, effectively avoids the risk of clip displacement after reflow curing. However, this design also presents difficulties in measuring the bonding force of the clips. It cannot accurately determine the bonding force between the clip source and the chip, or between the clip gate and the chip (due to the limiting structures and welding on the tail of the clip and frame). The actual measured bonding force is the total bonding force of the clip source and chip, the clip gate and chip, the welding bonding between the clip and frame, and the limiting forces. Therefore, a tool capable of cutting the soldered power device packaging unit is needed to measure the bonding force between the clip source and chip, and between the clip gate and chip. When using conventional cutting fixtures, the connecting piece may delaminate at the welding position of each component during the cutting process, or excessively compress the joint between the connecting piece and the component. This can cause severe deformation of the power device packaging unit at the cutting position after cutting, resulting in deviations in the measurement of the total bonding force. Consequently, the actual bonding force after the connecting piece is welded cannot be effectively tested and verified, making it impossible to strictly control the reliability of the product.

[0005] In view of this, the problem that existing conventional cutting fixtures cause delamination and severe deformation at the welding position of the connecting piece and the packaging unit component when cutting the diode chip of the power device package unit to be tested, resulting in inaccurate measurement of bonding force, has become the research topic to be solved by this utility model. Utility Model Content

[0006] The purpose of this invention is to provide a cutting fixture and cutting equipment for welding and testing power device packaging units, which solves the problem that existing traditional cutting fixtures may damage the pins and chips when cutting the pins of diode chips, resulting in inaccurate bonding force measurement.

[0007] To achieve the above objectives, in a first aspect, this utility model proposes a cutting fixture for welding and testing power device packaging units, used for cutting operations during welding and testing of power device packaging units. The power device packaging unit includes a chip and a connecting piece, with the chip and connecting piece welded and fixed. The connection between the chip and the connecting piece has a cutting area. Its innovation lies in:

[0008] The cutting fixture includes a load-bearing component, a lower mold component, an upper mold component, and a guide component.

[0009] The supporting component includes a base plate and a lower mold fixing plate, with the lower mold fixing plate installed on the upper surface of the base plate.

[0010] The lower mold assembly is mounted on the lower mold fixing plate. The lower mold assembly includes a lower mold body. The upper surface of the lower mold body is provided with a first support portion and a second support portion for supporting the connecting piece. A cutting groove is provided on the lower mold body between the first support portion and the second support portion corresponding to the cutting area of ​​the power device packaging unit.

[0011] The upper mold assembly is positioned above the lower mold assembly via a guide assembly. The upper mold assembly includes an upper mold connecting plate, on which a vertically floating stripper plate is connected. An elastic element is installed between the upper mold connecting plate and the stripper plate. The stripper plate has a downward-facing abutment surface corresponding to the first and second bearing portions. The stripper plate has a tool path that passes through the abutment surface. A cutter is installed on the upper mold connecting plate in the tool path. The cutting groove of the lower mold body is located on the displacement path of the cutter.

[0012] To achieve the above objectives, in a second aspect, this utility model proposes a cutting device for welding and testing power device packaging units. The cutting device includes a machine base, a cutting drive assembly, and a cutting fixture as described in the first aspect of this utility model. The cutting drive assembly is one of a manual pressing assembly, a pneumatic pressing assembly, a hydraulic pressing assembly, or an electric pressing assembly.

[0013] The relevant contents of this utility model are explained as follows:

[0014] 1. In the above-mentioned technical solution of this utility model, the existing conventional cutting fixtures, when cutting the diode chip of the power device package unit to be tested, cause delamination and severe deformation at the welding position of the connecting piece and the package unit assembly, resulting in inaccurate bonding force measurement. Therefore, an innovative cutting fixture and a cutting device for welding testing of power device package units are designed. This is mainly achieved by improving the design of the lower mold assembly and the upper mold assembly in the cutting fixture. Specifically, a first support portion and a second support portion are provided in the cutting area of ​​the lower mold assembly corresponding to the power device package unit, and a cutting groove is provided between the first support portion and the second support portion to allow the power device package unit to be... When placed on the lower mold body, the area to be cut is supported by the first and second support parts, and a cutting groove is provided to facilitate the insertion of the cutter. In the upper mold assembly, a floating stripper plate and a cutter located in the tool channel of the stripper plate are provided in the cutting area corresponding to the power device packaging unit. Before the cutting operation, the stripper plate approaches and presses against the power device packaging unit located on the first and second support parts to prevent the connecting piece and the welding position in the power device packaging unit from shifting during the cutting process. This ensures that the cut surface between the connecting piece and each component is flat after cutting, and there is no delamination at the joint. This provides a more accurate and realistic test object for subsequent joint testing of each part.

[0015] 2. In the technical solution of the first aspect above, the cutting fixture is configured to have an initial state, a pressing state, a cutting state, and an unloading state;

[0016] In the initial state, the unloading plate tends to move downward under the action of the elastic element and its own gravity. The lower end of the cutter is located in the cutting channel and is located in the upward position of the contact surface. The contact surface is located away from the first bearing part and the second bearing part.

[0017] In the pressing state, the upper mold assembly is moved downward as a whole under the external driving action, the unloading plate approaches and abuts against the power device packaging unit located on the first bearing part and the second bearing part, the elastic element is compressed, the cutter moves downward from the tool channel and approaches the cutting area of ​​the power device packaging unit, and the lower end of the cutter is located in the tool channel and is close to or flush with the surface of the abutment surface.

[0018] In the cutting state, the upper mold assembly continues to move downward under the external driving action, and the lower end of the cutter passes through the cutting channel and applies cutting force towards the cutting area of ​​the power device packaging unit. After the lower end of the cutter cuts the cutting area of ​​the connecting piece, it enters the cutting groove.

[0019] In the unloading state, as the upper mold assembly moves upward, the unloading plate continues to press the power device packaging unit in place while the elastic element releases its compressive elastic force. The lower end of the cutter moves upward, disengages from the cutting groove, and enters the cutting channel. Then, the unloading plate separates from the power device packaging unit.

[0020] 3. In the technical solution of the first aspect above, the lower mold fixing plate is provided with an installation groove, and the lower mold body is positioned and installed in the installation groove to avoid the lower mold body from shifting to the left or right during the cutting process. The lower mold fixing plate has a discharge groove that is connected to the cutting groove and located directly below the cutting groove. During the cutting process, the debris falling from the cutting groove can fall out of the discharge groove to avoid accumulation.

[0021] 4. In the technical solution of the first aspect above, two support plates are mounted on the upper surface of the base plate. The support plates are located on both sides of the lower mold fixing plate and the lower mold body. The two support plates support both sides of the lower mold body located in the mounting groove, so as to prevent the lower mold body from shifting in the front and back direction during the cutting process, so as to make the lower mold assembly more firmly fixed.

[0022] 5. In the technical solution of the first aspect above, a discharge chute for discharging waste material is provided on the base plate. The discharge chute is connected to the discharge chute and the cutting chute, so as to discharge the debris better and faster and avoid accumulation that affects the cutting operation.

[0023] 6. In the technical solution of the first aspect above, the upper mold assembly further includes an upper mold fixing plate, and the upper mold connecting plate is fixedly connected to the lower part of the upper mold fixing plate, so as to make the overall structure of the upper mold assembly more robust and the pressing of the upper mold assembly more stable.

[0024] 7. In the technical solution of the second aspect above, the guiding component includes a guide post and a guide sleeve. The guide sleeve is fixedly installed on the upper mold fixing plate. The lower end of the guide post is fixed to the base plate. The upper end of the guide post passes through the upper mold fixing plate and the guide sleeve and then guides the upper mold component to provide good guidance for the cutting area of ​​the power device packaging unit in the upper mold component and avoids deviation.

[0025] 8. In the technical solution of the first aspect above, the abutting surface is a hollow rectangular plane with a cutting channel in the middle. The abutting surface is U-shaped, and the unloading plate can completely abut the periphery of the cutting area. During the process of the cutter extending from the cutting channel to cut the connecting piece, the abutting surface always abuts the cutting area, and the power device packaging unit also always abuts the first support part and the second support part, thereby further avoiding the delamination and deformation of the connecting piece and other components during the cutting process, and further improving the testing accuracy and authenticity of the power device packaging unit under test.

[0026] 9. In the technical solution of the second aspect above, the cutting drive assembly adopts a manual pressing assembly, which includes a drive handle and a pressure cylinder, and the output end of the lower part of the pressure cylinder is fixedly connected to the upper mold assembly. This is suitable for small-batch welding tests of power device packaging units, and features a simple structure, low cost, and ease of use.

[0027] 10. In this utility model, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] 11. In this utility model, the terms "upper", "lower", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional assembly relationship shown in the drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0029] 12. In addition, it should be noted in the description of this utility model that if the terms "first" or "second" are used to limit the components, those skilled in the art should know that the use of the terms "first" or "second" is only for the convenience of describing this utility model and simplifying the description, and unless otherwise stated, the above terms have no special meaning.

[0030] Due to the application of the above solution, this utility model has the following advantages and effects compared with the prior art:

[0031] The above-mentioned solution of this utility model addresses the problem that conventional cutting fixtures, when cutting diode chips in power device package units to be tested, cause delamination and severe deformation at the welding position between the connecting piece and the package unit assembly, leading to inaccurate bonding force measurements. Therefore, this invention innovatively designs a cutting fixture and a cutting device for welding and testing power device package units. The main improvement is achieved through redesigning the lower mold assembly and upper mold assembly in the cutting fixture. Specifically, a first support portion and a second support portion are provided in the cutting area of ​​the lower mold assembly corresponding to the power device package unit, and a cutting groove is provided between the first and second support portions to allow the power device package unit to be placed... On the lower mold body, the area to be cut is supported by the first and second support parts, and a cutting groove is provided to facilitate the insertion of the cutter. In the upper mold assembly, a floating stripper plate and a cutter located in the tool path channel of the stripper plate are provided in the cutting area corresponding to the power device packaging unit. Before the cutting operation, the stripper plate approaches and presses against the power device packaging unit located on the first and second support parts, preventing the connector and welding positions in the power device packaging unit from shifting during the cutting process. This ensures that the cut surface between the connector and each component is flat after cutting, and that there is no delamination at the joint. This provides a more accurate and realistic test object for subsequent bonding tests of various parts. The cutting fixture can effectively and accurately measure the bonding force between the connector source end and the chip, and the bonding force between the connector gate end and the chip, avoiding the problem of overall bonding force measurement deviation between the connector and the component. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural diagram of the cutting device according to an embodiment of the present utility model;

[0033] Figure 2 This is a front view of the overall structure of the cutting device according to an embodiment of the present utility model;

[0034] Figure 3 This is a three-dimensional schematic diagram of the cutting fixture according to an embodiment of the present utility model (viewpoint 1);

[0035] Figure 4This is a three-dimensional schematic diagram of the cutting fixture according to an embodiment of the present utility model (viewpoint 2);

[0036] Figure 5 This is a left view of the cutting fixture according to an embodiment of the present invention;

[0037] Figure 6 for Figure 5 Schematic diagram of the cross section along the AA direction;

[0038] Figure 7 This is a front view of the cutting fixture according to an embodiment of the present invention;

[0039] Figure 8 for Figure 7 Schematic diagram of the cross section along the BB direction;

[0040] Figure 9 This is a schematic diagram of the cooperation between the upper mold assembly and the lower mold assembly in an embodiment of this utility model (viewpoint 1);

[0041] Figure 10 This is a schematic diagram of the cooperation between the upper mold assembly and the lower mold assembly in an embodiment of this utility model (viewpoint 2);

[0042] Figure 11 This is a schematic diagram of the cutting fixture in its initial state according to an embodiment of the present invention;

[0043] Figure 12 This is a schematic diagram of the cutting fixture in the pressing state according to an embodiment of the present invention;

[0044] Figure 13 This is a schematic diagram of the cutting fixture in the cutting state according to an embodiment of the present invention;

[0045] Figure 14 This is a schematic diagram of the cutting fixture in the unloading state according to an embodiment of the present invention;

[0046] Figure 15 This is a schematic diagram of the upper mold assembly's cutter extending downwards in an embodiment of this utility model;

[0047] Figure 16 This is a schematic diagram showing the cooperation between the lower mold assembly and the power device packaging unit in an embodiment of this utility model;

[0048] Figure 17 This is a three-dimensional schematic diagram of a power device packaging unit;

[0049] Figure 18 This is a three-dimensional schematic diagram of the lower mold assembly in an embodiment of the present invention (view 1).

[0050] Figure 19 This is a three-dimensional schematic diagram (view 2) of the lower mold assembly in an embodiment of this utility model.

[0051] Figure 20 This is a cross-sectional schematic diagram of the lower mold assembly in an embodiment of this utility model.

[0052] The parts shown in the above attached diagram are illustrated below:

[0053] 1. Load-bearing components;

[0054] 11. Base plate; 111. Discharge chute; 12. Lower mold fixing plate; 121. Mounting groove; 122. Discharge chute; 13. Support plate;

[0055] 2. Lower mold assembly;

[0056] 21. Lower mold body; 22. First bearing part; 23. Second bearing part; 24. Cutting groove;

[0057] 3. Upper mold assembly;

[0058] 31. Upper mold connecting plate; 32. Stripper plate; 321. Abutment surface; 322. Tool path; 323. Guide rod; 33. Cutting blade; 34. Elastic element; 35. Upper mold fixing plate;

[0059] 4. Guide assembly; 41. Guide post; 42. Guide sleeve;

[0060] 5. Machine tools;

[0061] 6. Cut-off drive assembly; 61. Drive handle; 62. Pressure cylinder;

[0062] 9. Power device packaging unit; 90. Cut-off area; 91. Chip; 92. Connecting piece; 93. Frame; 94. Limiting structure. Detailed Implementation

[0063] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0064] This invention addresses the problem that conventional cutting fixtures, when cutting diode chips in power device packaging units to be tested, cause delamination and severe deformation at the welding position between the connecting piece and the packaging unit assembly, resulting in inaccurate measurement of bonding force. Therefore, this invention innovatively designs a cutting fixture and a cutting device for welding testing of power device packaging units.

[0065] Example 1, as Figures 3 to 20As shown, Embodiment 1 of this utility model discloses a cutting fixture for welding and testing power device packaging units, used for cutting operations during welding and testing of power device packaging units. The power device packaging unit includes a chip 91 and a connecting piece 92. The chip 91 and the connecting piece 92 are welded and fixed. The connection between the chip 91 and the connecting piece 92 has a cutting area 90. Specifically, see... Figure 17 As shown, the power device packaging unit 9 generally includes a chip 91, a connector 92, a frame 93, and a limiting structure 94, in order to... Figure 17 The cut-off area 90 shown in the figure cuts off the power device package unit in preparation for subsequent soldering tests of the power device package unit.

[0066] like Figures 1 to 4 As shown, the cutting fixture includes a support component 1, a lower mold component 2, an upper mold component 3, and a guide component 4.

[0067] like Figures 1 to 4 As shown, the supporting component 1 includes a base plate 11 and a lower mold fixing plate 12, with the lower mold fixing plate 12 installed on the upper surface of the base plate 11.

[0068] like Figures 18 to 19 As shown, the lower mold assembly 2 is mounted on the lower mold fixing plate 12. The lower mold assembly 2 includes a lower mold body 21. The upper surface of the lower mold body 21 is provided with a first support portion 22 and a second support portion 23 for supporting the connecting piece 92. A cutting groove 24 is provided on the lower mold body 21 between the first support portion 22 and the second support portion 23 corresponding to the cutting area 90 of the power device packaging unit.

[0069] like Figure 3 and Figures 5 to 8 As shown, the upper mold assembly 3 is positioned above the lower mold assembly 2 via a guide assembly 4. The upper mold assembly 3 includes an upper mold connecting plate 31, on which a vertically floating unloading plate 32 is connected. An elastic element 34 is installed between the upper mold connecting plate 31 and the unloading plate 32. The unloading plate 32 has a downward-facing abutment surface 321 corresponding to the first bearing part 22 and the second bearing part 23. The unloading plate 32 has a tool passage 322 passing through the abutment surface 321. A cutter 33 located in the tool passage 322 is installed on the upper mold connecting plate 31. The cutting groove 24 of the lower mold body 21 is located on the displacement path of the cutter 33.

[0070] Through the implementation of Embodiment 1 of this utility model, the lower mold assembly 2 and the upper mold assembly 3 in the cutting fixture have been improved. Specifically, a first support portion 22 and a second support portion 23 are provided in the cutting area 90 corresponding to the power device packaging unit in the lower mold assembly 2, and a cutting groove 24 is provided between the first support portion 22 and the second support portion 23. This allows the area near the part to be cut when the power device packaging unit is placed on the lower mold body 21 to be supported by the first support portion 22 and the second support portion 23. The cutting groove 24 facilitates the insertion of the cutter 33. The upper mold assembly 3 corresponds to the power device... The cutting area 90 of the packaging unit is equipped with a floating unloading plate 32 and a cutter 33 located in the cutting channel 322 of the unloading plate 32. Before the cutting operation, the unloading plate 32 approaches and presses against the power device packaging unit located on the first support part 22 and the second support part 23 to prevent the connecting piece 92 and the welding position in the power device packaging unit from shifting during the cutting process. This ensures that the cross-section between the connecting piece 92 and each component is flat after cutting, and that there is no delamination at the joint. This provides a more accurate and realistic test object for subsequent joint tests of each part.

[0071] In a first embodiment of this utility model, the cutting fixture is configured to have an initial state, a pressing state, a cutting state, and an unloading state, as detailed below:

[0072] like Figure 11 As shown, in the initial state, the unloading plate 32 tends to move downward under the action of the elastic member 34 and its own gravity. The lower end of the cutter 33 is located in the cutting channel 322 and is located in the upward position of the contact surface 321. The contact surface 321 is located away from the first bearing part 22 and the second bearing part 23.

[0073] like Figure 12 As shown, in the pressing state, the upper mold assembly 3 is moved downward as a whole under the external driving action, the unloading plate 32 approaches and abuts against the power device packaging unit located on the first bearing part 22 and the second bearing part 23, the elastic element 34 is compressed, and the cutter 33 moves downward from the cutting channel 322 and approaches the cutting area 90 of the power device packaging unit. The lower end of the cutter 33 is located in the cutting channel 322 and is close to or flush with the surface of the abutment surface 321.

[0074] like Figure 13 As shown, in the cutting state, the upper mold assembly 3 continues to move downward under the action of external drive, and the lower end of the cutter 33 passes through the cutting channel 322 and applies a cutting force toward the cutting area 90 of the power device packaging unit. After the lower end of the cutter 33 cuts the cutting area 90 of the connecting piece 92, it enters the cutting groove 24.

[0075] like Figure 14As shown, in the unloading state, during the upward displacement of the upper mold assembly 3, the unloading plate 32 continues to press the power device packaging unit while the elastic member 34 releases the compressive elastic force. The lower end of the cutter 33 moves upward, disengages from the cutting groove 24, and enters the cutting channel 322. The unloading plate 32 then disengages from the power device packaging unit.

[0076] In the first embodiment of this utility model, the lower mold fixing plate 12 is provided with an installation groove 121, and the lower mold body 21 is positioned and installed in the installation groove 121 to prevent the lower mold body 21 from shifting to the left or right during the cutting process. The lower mold fixing plate 12 has a discharge groove 122 that is connected to the cutting groove 24 and located directly below the cutting groove 24. During the cutting process, the debris falling from the cutting groove 24 can fall out of the discharge groove 122 to avoid accumulation.

[0077] In the first embodiment of this utility model, two support plates 13 are mounted on the upper surface of the base plate 11. The support plates 13 are located on both sides of the lower mold fixing plate 12 and the lower mold body 21. The two support plates 13 support both sides of the lower mold body 21 located in the mounting groove 121, thereby preventing the lower mold body 21 from shifting in the front and back direction during the cutting process, so as to make the lower mold assembly 2 more firmly fixed.

[0078] In the first embodiment of this utility model, a discharge chute 111 for discharging waste material is provided on the bottom plate 11. The discharge chute 111 is connected to the discharge chute 122 and the cutting chute 24, so as to discharge the debris better and faster and avoid accumulation affecting the cutting operation.

[0079] In the first embodiment of this utility model, the upper mold assembly 3 further includes an upper mold fixing plate 35, and the upper mold connecting plate 31 is fixedly connected to the lower part of the upper mold fixing plate 35, so as to make the overall structure of the upper mold assembly 3 more robust and the pressing of the upper mold assembly 3 more stable.

[0080] In the first embodiment of this utility model, the guiding component 4 includes a guide post 41 and a guide sleeve 42. The guide sleeve 42 is fixedly installed on the upper mold fixing plate 35. The lower end of the guide post 41 is fixed to the base plate 11. The upper end of the guide post 41 passes through the upper mold fixing plate 35 and the guide sleeve 42 and then guides the upper mold component 3 to provide good guidance for the cutter 33 in the upper mold component 3 to cut towards the cutting area 90 of the power device packaging unit and avoid deviation.

[0081] In the first embodiment of this utility model, the abutment surface 321 is a hollow rectangular plane with a cutting channel 322 in the middle. The abutment surface 321 is U-shaped. The unloading plate 32 can completely abut against the periphery of the cutting area 90. During the process of the cutter 33 extending from the cutting channel 322 to cut the connecting piece 92, the abutment surface 321 always abuts against the cutting area 90, and the power device packaging unit also always abuts against the first support part 22 and the second support part 23. This further avoids the delamination and deformation of the connecting piece 92 and other components during the cutting process, and further improves the testing accuracy and authenticity of the power device packaging unit under test.

[0082] In Embodiment 1 of this utility model, as Figure 15 As shown, the elastic element 34 is a spring, which is sleeved on a guide rod 323. One end of the spring acts on the upper surface of the unloading plate 32, and the other end acts on the upper surface of the upper mold connecting plate 31. This provides good floating capability for the unloading plate 32. This invention is not limited to this; other elastic elements 34 such as compression springs or disc springs can also be provided, and one or more guide rods 323 can be provided.

[0083] Example 2, as Figure 1 , Figure 2 As shown in Embodiment 2 of this utility model, a cutting device for welding testing of power device packaging units is proposed. The cutting device includes a machine base 5, a cutting drive assembly 6, and a cutting fixture as described in Embodiment 1 of this utility model. The cutting drive assembly 6 is one of a manual pressing assembly, a pneumatic pressing assembly, a hydraulic pressing assembly, or an electric pressing assembly. Preferably, the cutting drive assembly 6 is a manual pressing assembly, which includes a drive handle 61 and a pressure cylinder 62. The output end of the lower part of the pressure cylinder 62 is fixedly connected to the upper mold assembly 3. This is suitable for welding testing of small batches of power device packaging units, with a simple structure, low cost, and ease of use.

[0084] Example 3 of this utility model proposes a cutting device, which includes a machine base 5, a cutting drive assembly 6, and a cutting fixture. The cutting drive assembly 6 is a manual pressing assembly, which includes a drive handle 61 and a pressure cylinder 62. The output end of the lower part of the pressure cylinder 62 is fixedly connected to the upper mold assembly 3. The cutting fixture includes a bearing assembly 1, a lower mold assembly 2, an upper mold assembly 3, and a guide assembly 4.

[0085] In embodiment 3, the supporting component 1 includes a base plate 11, a lower mold fixing plate 12, and a support plate 13. The lower mold fixing plate 12 is installed on the upper surface of the base plate 11. The lower mold fixing plate 12 has an installation groove 121 facing upward and a discharge groove 122 facing downward. Two support plates 13 are mounted on the upper surface of the base plate 11.

[0086] In Embodiment 3, the lower mold assembly 2 includes a lower mold body 21, which is positioned and installed in the mounting groove 121. The support plates 13 are located on both sides of the lower mold fixing plate 12 and the lower mold body 21, and the two support plates 13 support both sides of the lower mold body 21 located in the mounting groove 121. The upper surface of the lower mold body 21 is provided with a first support portion 22 and a second support portion 23 for carrying the connecting piece 92. A cutting groove 24 is provided on the lower mold body 21 between the first support portion 22 and the second support portion 23 corresponding to the cutting area 90 of the power device packaging unit.

[0087] In embodiment three, the upper mold assembly 3 includes an upper mold connecting plate 31 and an upper mold fixing plate 35. The upper mold fixing plate 35 is fixedly connected to the lower part of the upper mold connecting plate 31. A floating stripper plate 32 is connected to the upper mold connecting plate 31. An elastic element 34, which is a spring, is installed between the upper mold connecting plate 31 and the stripper plate 32. The elastic element 34 is sleeved on a guide rod 323. One end of the spring acts on the upper surface of the stripper plate 32, and the other end acts on the upper surface of the upper mold connecting plate 31. The stripper plate 32 has a downward-facing abutment surface 321 corresponding to the first bearing part 22 and the second bearing part 23. The abutment surface 321 is U-shaped. The stripper plate 32 has a cutting channel 322 passing through the abutment surface 321. A cutter 33 located in the cutting channel 322 is installed on the upper mold connecting plate 31. The cutting groove 24 of the lower mold body 21 is located on the displacement path of the cutter 33.

[0088] In Embodiment 3, the guide assembly 4 includes two guide posts 41 and two guide sleeves 42. The guide sleeves 42 are fixedly installed on the upper mold fixing plate 35. The lower end of the guide post 41 is fixed to the base plate 11. The upper end of the guide post 41 passes through the upper mold fixing plate 35 and the guide sleeves 42 and then guides the upper mold assembly 3.

[0089] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A cutting fixture for welding and testing power device packaging units, used for cutting operations during welding and testing of power device packaging units, wherein the power device packaging unit (9) includes a chip (91) and a connecting piece (92), the chip (91) and the connecting piece (92) are welded and fixed, and the connection between the chip (91) and the connecting piece (92) has a cutting area (90), characterized in that: The cutting fixture includes a load-bearing assembly (1), a lower mold assembly (2), an upper mold assembly (3), and a guide assembly (4); The supporting component (1) includes a base plate (11) and a lower mold fixing plate (12), and the lower mold fixing plate (12) is installed on the upper surface of the base plate (11); The lower mold assembly (2) is mounted on the lower mold fixing plate (12). The lower mold assembly (2) includes a lower mold body (21). The upper surface of the lower mold body (21) is provided with a first support portion (22) and a second support portion (23) for supporting the connecting piece (92). A cutting groove (24) is provided on the lower mold body (21) between the first support portion (22) and the second support portion (23) corresponding to the cutting area (90) of the power device packaging unit. The upper mold assembly (3) is positioned above the lower mold assembly (2) via a guide assembly (4). The upper mold assembly (3) includes an upper mold connecting plate (31). A floating stripper plate (32) is connected to the upper mold connecting plate (31). An elastic element (34) is installed between the upper mold connecting plate (31) and the stripper plate (32). The stripper plate (32) has a downward-facing contact surface (321) corresponding to the first bearing part (22) and the second bearing part (23). The stripper plate (32) has a tool passage (322) passing through the contact surface (321). A cutter (33) located in the tool passage (322) is installed on the upper mold connecting plate (31). The cutting groove (24) of the lower mold body (21) is located on the displacement path of the cutter (33).

2. The cutting fixture for welding and testing power device packaging units according to claim 1, characterized in that: The cutting fixture is configured to have an initial state, a pressing state, a cutting state, and an unloading state; In the initial state, the unloading plate (32) tends to move downward under the action of the elastic element (34) and its own gravity. The lower end of the cutter (33) is located in the feed channel (322) and is located in the upward position of the contact surface (321). The contact surface (321) is located away from the first bearing part (22) and the second bearing part (23). In the pressing state, the upper mold assembly (3) is moved downward as a whole under the external driving action, the unloading plate (32) approaches and abuts against the power device packaging unit located on the first bearing part (22) and the second bearing part (23), the elastic element (34) is compressed, the cutter (33) moves downward from the tool channel (322) and approaches the cutting area (90) of the power device packaging unit, the lower end of the cutter (33) is located in the tool channel (322) and is close to or flush with the surface of the abutment surface (321); In the cutting state, the upper die assembly (3) continues to move downward under the action of an external drive. The lower end of the cutting tool (33) passes through the tool feed channel (322) and applies a cutting force to the cutting area (90) of the power device packaging unit. After the lower end of the cutting tool (33) cuts the cutting area (90) of the connecting piece (92), it enters the cutting groove (24). In the unloading state, during the upward movement of the upper die assembly (3), first, the unloading plate (32) continues to press against the power device packaging unit under the condition that the elastic member (34) releases the compressed elastic acting force. The lower end of the cutting tool (33) moves upward and disengages from the cutting groove (24) and enters the tool feed channel (322). Then, the unloading plate (32) disengages from the power device packaging unit.

3. The cutting fixture for welding and testing power device packaging units according to claim 1, characterized in that: An installation groove (121) is formed on the lower die fixing plate (12). The lower die body (21) is positioned and installed in the installation groove (121). The lower die fixing plate (12) has a discharge groove (122) that is connected to the cutting groove (24) and is located directly below the cutting groove (24).

4. The cutting fixture for welding and testing power device packaging units according to claim 3, characterized in that: Two support plates (13) are installed on the upper surface of the bottom plate (11). The support plates (13) are located on both sides of the lower die fixing plate (12) and the lower die body (21). The two support plates (13) support both sides of the lower die body (21) located in the installation groove (121).

5. The cutting fixture for welding and testing power device packaging units according to claim 3, characterized in that: A discharge inclined groove (111) for discharging waste is formed on the bottom plate (11). The discharge inclined groove (111) is connected to the discharge groove (122) and the cutting groove (24).

6. The cutting fixture for welding and testing power device packaging units according to claim 1, characterized in that: The upper die assembly (3) further includes an upper die fixing plate (35). The upper die connecting plate (31) is fixedly connected below the upper die fixing plate (35).

7. The cutting fixture for welding and testing power device packaging units according to claim 6, characterized in that: The guiding component (4) includes a guide post (41) and a guide sleeve (42). The guide sleeve (42) is fixedly installed on the upper die fixing plate (35). The lower end of the guide post (41) is fixed to the bottom plate (11). The upper end of the guide post (41) passes through the upper die fixing plate (35) and the guide sleeve (42) and then guides and acts on the upper die assembly (3).

8. The cutting fixture for welding and testing power device packaging units according to claim 1, characterized in that: The abutting surface (321) is a hollow rectangular plane with a tool feed channel (322) formed in the middle. The abutting surface (321) is in a shape of a double-square frame.

9. A cutting device for welding and testing power device packaging units, characterized in that: The cutting device includes a machine table (5), a cutting drive component (6), and the cutting fixture according to any one of claims 1 to 8. The cutting drive component (6) is one of a manual pressing component, a pneumatic pressing component, a hydraulic pressing component, or an electric pressing component.

10. The cutting device for welding and testing power device packaging units according to claim 9, characterized in that: The cutting drive component (6) adopts a manual pressing component. The cutting drive component (6) includes a drive handle (61) and a pressing cylinder (62). The output end at the lower part of the pressing cylinder (62) is fixedly connected to the upper die assembly (3).

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