IGBT fixed heat dissipation structure and PTC heater

Abstract

The utility model belongs to the technical field of PTC heater heat dissipation, and specifically discloses an IGBT fixed heat dissipation structure and a PTC heater, the IGBT fixed heat dissipation structure comprises a heat dissipation block, an IGBT chip and a pressing assembly, the IGBT chip is placed on a heat dissipation table top of the heat dissipation block, and the pressing assembly comprises a pressing block and an elastic compression member. The elastic compression piece is arranged on the side, facing the heat dissipation table top, of the pressing block, the pressing block is connected with the heat dissipation table top, the elastic compression piece tightly presses the IGBT chip on the heat dissipation table top through elastic force, the IGBT chip and the heat dissipation table top are tightly attached, heat resistance is small, and heat dissipation is good. Meanwhile, the elastic compression piece is insulated from the IGBT chip, the creepage distance and creepage gap of the IGBT chip are large, the IGBT chip is not prone to being broken down to cause short circuit, and safety and reliability are high. The utility model also provides a PTC heater which comprises the IGBT fixed heat radiation structure.

Description

Technical Field

[0001] The utility model relates to the technical field of heat dissipation of PTC heaters, in particular to an IGBT fixed heat dissipation structure and a PTC heater. Background Art

[0002] Generally, a vehicle is equipped with an air conditioning system to control the internal temperature of the vehicle. The air conditioning system includes a Positive Temperature Coefficient Heater (PTC heater), which heats the air flow entering the passenger compartment to keep the temperature in the passenger compartment suitable in winter.

[0003] Generally speaking, the power adjustment of the PTC heater adopts a stepless adjustment method, and this adjustment method is inseparable from the Insulated Gate Bipolar Transistor (IGBT chip), a high-power semiconductor device. By inputting different duty cycles, the IGBT chip continuously performs switching actions to achieve the adjustment of the heating power. Therefore, a large amount of heat is generated when the IGBT chip is working. If the heat dissipation effect is not good, the temperature of the IGBT chip will rise sharply in a short time. When the temperature rises to the maximum junction temperature allowed by the IGBT chip, the performance of the IGBT chip will decline sharply, and even cause the IGBT chip to burn out and lead to a short circuit, so that the PTC heater loses its power adjustment function.

[0004] The existing fixed heat dissipation forms of IGBT chips in PTC heaters include the following methods:

[0005] 1. When the upper cover of the control box is locked, the heat dissipation surface of the IGBT chip is directly pressed tightly, and the heat dissipation surface of the IGBT chip is attached to the heat dissipation table surface of the upper cover to achieve heat dissipation. In this fixed heat dissipation structure of the IGBT chip, the IGBT chip and the upper cover are blindly attached and pressed tightly. After assembling the upper cover, it is impossible to judge whether they are perfectly attached; there is a lack of fitting gap compensation measures. Under the long-term action of thermal expansion and contraction and vibration, a certain gap may be generated between the heat dissipation surface of the IGBT chip and the heat dissipation table surface of the upper cover, thereby increasing the thermal resistance and resulting in a decrease in the heat dissipation effect of the IGBT chip.

[0006] 2. The IGBT chip is first welded and fixed on the PCBA board. When the PCBA board is locked, the heat dissipation surface of the IGBT chip is directly pressed tightly against the heat dissipation table surface to achieve heat dissipation. In this fixed heat dissipation structure of the IGBT chip, there is also a lack of fitting gap compensation measures. Under the long-term action of thermal expansion and contraction and vibration, a certain gap will be generated between the heat dissipation surface of the IGBT chip and the heat dissipation table surface, thereby increasing the thermal resistance and resulting in a decrease in the heat dissipation effect of the IGBT chip;

[0007] 3. The bolts directly pass through the assembly holes on the IGBT chip and are then locked to the heat dissipation tabletop. In this fixed heat dissipation structure of the IGBT chip, since the bolts are conductors and are very close to the IGBT chip, when applied to products with a high-voltage platform, due to insufficient creepage distance, insulation failure will occur, resulting in the IGBT chip being broken down and short-circuited.

[0008] 4. A metal stamping and bending formed elastic sheet presses against the back of the IGBT chip to make the heat dissipation surface of the IGBT chip closely fit with the heat dissipation tabletop. In this fixed heat dissipation structure of the IGBT chip, since the pressure points of the IGBT chip contact the elastic sheet made of metal material, the creepage distance and creepage clearance with the energized part of the IGBT chip need to be considered, and the required structural space is relatively large. And when applied to products with a high-voltage platform, due to insufficient creepage distance, insulation failure will occur, resulting in the IGBT chip being broken down and short-circuited. Utility Model Content

[0009] The purpose of the present utility model is to provide an IGBT fixed heat dissipation structure and a PTC heater, which can make the IGBT chip closely fit with the heat dissipation tabletop, not easily generate gaps, and at the same time ensure good insulation performance and not easily have the risk of the IGBT chip being broken down and short-circuited.

[0010] To achieve this purpose, the present utility model adopts the following technical solutions:

[0011] On the one hand, the present utility model provides an IGBT fixed heat dissipation structure, including:

[0012] A heat dissipation block having a heat dissipation tabletop;

[0013] An IGBT chip disposed on the heat dissipation tabletop;

[0014] A pressing assembly including a pressing block and an elastic compression member. The projection of the pressing block on the heat dissipation tabletop at least partially coincides with the projection of the IGBT chip on the heat dissipation tabletop. An installation portion is provided on the side of the pressing block facing the heat dissipation tabletop. The elastic compression member is connected to the installation portion. The pressing block is connected to the heat dissipation tabletop. The elastic compression member presses the IGBT chip against the heat dissipation tabletop by elastic force, and the elastic compression member is insulated from the IGBT chip.

[0015] Optionally, the IGBT fixed heat dissipation structure further includes a locking member. An assembly hole is provided on the pressing block, and a locking hole position is provided on the heat dissipation block. The locking member passes through the assembly hole and is then connected to the locking hole position.

[0016] Optionally, a plurality of the locking members, the assembly holes, and the locking hole positions are also provided, and the locking members, the assembly holes, and the locking hole positions correspond to each other one by one. Each locking member passes through the corresponding assembly hole and is connected to one of the locking hole positions.

[0017] Optionally, a support column is further provided on one side of the pressing block facing the heat dissipation tabletop. The assembly hole is provided through the support column, and the support column abuts against one side of the heat dissipation tabletop facing the pressing block.

[0018] Optionally, a plurality of IGBT chips are provided, and the plurality of IGBT chips are arranged at intervals on the heat dissipation tabletop. A plurality of mounting portions and elastic compression members are also provided on the pressing block, and the mounting portions and the elastic compression members correspond to each other one by one. One elastic compression member is provided at each mounting portion, and each IGBT chip abuts against at least one elastic compression member.

[0019] Optionally, the mounting portion includes a positioning groove and a positioning post. The positioning post is provided at the bottom of the positioning groove and extends towards the direction close to the heat dissipation tabletop. A central hole is provided in the center of the elastic compression member, and the positioning post passes through and is fixed in the central hole. The positioning groove is used to accommodate the elastic compression member.

[0020] Optionally, the mounting portion includes a positioning groove and a mounting hole. The mounting hole is arranged at the bottom of the positioning groove. The elastic compression member includes an integrally formed main body portion and a fixing portion. The fixing portion passes through and is fixed in the mounting hole, and the positioning groove is used to accommodate the main body portion.

[0021] Optionally, a limiting flange is provided on one side of the pressing block facing the heat dissipation tabletop. The end of the limiting flange has a limiting surface, and the limiting surface is used to abut against the IGBT chip.

[0022] Optionally, the IGBT fixed heat dissipation structure is arranged in the control box. A guiding groove is provided on the pressing block, and a protruding portion is provided on the control box or the heat dissipation tabletop. The protruding portion is slidably connected to the guiding groove.

[0023] Optionally, a thermal conductive insulating sheet is provided between the heat dissipation tabletop and the IGBT chip. Both sides of the thermal conductive insulating sheet are respectively attached to the heat dissipation tabletop and the IGBT chip.

[0024] On the other hand, the present invention provides a PTC heater, including the IGBT fixed heat dissipation structure in any of the above solutions.

[0025] The beneficial effects of the present invention are as follows:

[0026] The present utility model provides an IGBT fixed heat dissipation structure, which includes a heat dissipation block, an IGBT chip, and a pressing component. The heat dissipation block has a heat dissipation tabletop, the IGBT chip is placed on the heat dissipation tabletop, and the pressing component presses the IGBT chip onto the heat dissipation tabletop. The pressing component includes a pressing block and an elastic compression member. The projection of the pressing block on the heat dissipation tabletop at least partially coincides with the projection of the IGBT chip on the heat dissipation tabletop. An installation portion is provided on the side of the pressing block facing the heat dissipation tabletop. The elastic compression member is connected to the installation portion. The pressing block is connected to the heat dissipation tabletop. The elastic compression member presses the IGBT chip onto the heat dissipation tabletop through an elastic force, so that the two are closely attached, with a small gap, a small thermal resistance, and good heat dissipation. At the same time, since the elastic compression member is insulated from the IGBT chip, the creepage distance and creepage clearance of the IGBT chip can be increased, and it is not easily broken down to cause a short circuit, with high safety and reliability.

[0027] The present utility model also provides a PTC heater, which includes the above-mentioned IGBT fixed heat dissipation structure. The temperature of the heat dissipation block in the above-mentioned IGBT fixed heat dissipation structure is relatively low, which can quickly take away the heat of the IGBT chip and has good heat dissipation. At the same time, it is ensured that the IGBT chip is not broken down and has high installation performance. Brief Description of the Drawings

[0028] Figure 1 is an exploded view of the IGBT fixed heat dissipation structure provided in Embodiment 1 of the present utility model;

[0029] Figure 2 is a sectional view of the IGBT fixed heat dissipation structure provided in Embodiment 1 of the present utility model;

[0030] Figure 3 is an exploded view of the pressing component provided in Embodiment 1 of the present utility model;

[0031] Figure 4 is a schematic structural diagram of the PTC heater provided in Embodiment 1 of the present utility model;

[0032] Figure 5 is a schematic structural diagram of the IGBT fixed heat dissipation structure provided in Embodiment 2 of the present utility model;

[0033] Figure 6 is an exploded view of the IGBT fixed heat dissipation structure provided in Embodiment 2 of the present utility model;

[0034] Figure 7 is an exploded view of the pressing component provided in Embodiment 2 of the present utility model.

[0035] In the figure:

[0036] 10. Circuit board; 11. Wiring socket; 20. Control box;

[0037] 100, Heat sink; 110, Heat dissipation tabletop; 120, Locking hole positions; 200, IGBT chip; 300, Pressing assembly; 310, Pressing block; 311, Mounting part; 3111, Positioning groove; 3112, Positioning post; 3113, Mounting hole; 312, Support post; 3121, Assembly hole; 313, Limiting flange; 314, Guide groove; 320, Elastic compression member; 321, Main body part; 3211, Central hole; 3212, Pressing plane; 322, Fixing part; 400, Locking member; 500, Thermal conductive insulating sheet; 510, Perforation. Detailed implementation manners

[0038] The present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. In addition, it should be noted that for the convenience of description, only parts related to the present utility model rather than all structures are shown in the drawings.

[0039] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0040] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "above the top", and "on the top" of the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is at a higher horizontal height than the second feature. The first feature being "below", "below the bottom", and "under the bottom" of the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the first feature is at a lower horizontal height than the second feature.

[0041] In the description of this embodiment, the orientation or positional relationship terms such as "above", "below", "left", and "right" are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and do not have special meanings.

[0042] Embodiment 1

[0043] As shown Figures 1-3 in the figure, this embodiment provides an IGBT fixed heat dissipation structure, including a heat dissipation block 100, an IGBT chip 200, and a pressing component 300. The heat dissipation block 100 has a heat dissipation tabletop 110, the IGBT chip 200 is placed on the heat dissipation tabletop 110, and the pressing component 300 presses the IGBT chip 200 onto the heat dissipation tabletop 110. The pressing component 300 includes a pressing block 310 and an elastic compression member 320. An installation portion 311 is provided on one side of the pressing block 310 facing the heat dissipation tabletop 110, and the elastic compression member 320 is connected to the installation portion 311. The elastic compression member 320 is made of an insulating material. For example, the elastic compression member 320 can be selected from rubber, silica gel, etc., so that the IGBT chip 200 and the pressing block 310 are insulated through the elastic compression member 320.

[0044] Furthermore, the pressing block 310 is detachably fixed on the heat dissipation tabletop 110, and the projection of the pressing block 310 on the heat dissipation tabletop 110 at least partially coincides with the projection of the IGBT chip 200 on the heat dissipation tabletop 110. Thus, the elastic compression member 320 provided on the pressing block 310 can press the IGBT chip 200 onto the heat dissipation tabletop 110 through elastic force, so that the two are closely attached, with a small gap, a small thermal resistance, and good heat dissipation. At the same time, since the elastic compression member 320 is insulated from the IGBT chip 200, the creepage distance and creepage clearance of the IGBT chip 200 can be increased, and it is not easily broken down to cause a short circuit, with high safety and reliability.

[0045] In this embodiment, an example is given where the projection of the pressing block 310 on the heat dissipation tabletop 110 can cover the projection of the IGBT chip 200 on the heat dissipation tabletop 110. The installation portion 311 on the pressing block 310 is located directly above the IGBT chip 200, and the elastic compression member 320 connected to the installation portion 311 acts on the central position of the IGBT chip 200. The elastic compression member 320 applies force to the IGBT chip 200 more evenly, with a good pressing effect on the IGBT chip 200. The IGBT chip 200 is closely attached to the heat dissipation tabletop 110, and the heat dissipation effect of the IGBT chip 200 is better.

[0046] Of course, in other embodiments, the projection of the pressing block 310 on the heat dissipation table 110 may also partially coincide with the projection of the IGBT chip 200 on the heat dissipation table 110. At this time, it is only necessary to ensure that the position of the mounting portion 311 provided on the pressing block 310 is directly above the IGBT chip 200. The elastic compression member 320 connected to the mounting portion 311 can also act on the central position of the IGBT chip 200 to uniformly apply pressure to the IGBT chip 200, achieving a good pressing effect on the IGBT chip 200. The IGBT chip 200 is in close contact with the heat dissipation table 110, and the heat dissipation effect of the IGBT chip 200 is better.

[0047] Optionally, the pressing block 310 can also be made of an insulating material. For example, the pressing block 310 can be made of plastic, so that the creepage distance and creepage clearance of the IGBT chip 200 are larger, the insulation effect between the pressing assembly 300 and the IGBT chip 200 is better, and the IGBT chip 200 is not easily broken down. Of course, in other embodiments, the pressing block 310 can also be made of a metal material.

[0048] It should be noted that the heat dissipation block 100 in this embodiment can be an independent module on the control box 20, and the heat dissipation block 100 and the control box 20 are of a split structure. The heat dissipation block 100 is made of a metal material. For example, the heat dissipation block 100 can be made of aluminum. By closely contacting the heat dissipation table 110 of the heat dissipation block 100 with the IGBT chip 200, the contact area between the heat dissipation table 110 and the IGBT chip is increased. The heat of the IGBT chip 200 is transferred to the heat dissipation block 100 through heat conduction, and then the heat dissipation block 100 dissipates the heat to the space on the side away from the IGBT chip 200, so as to continuously take away the heat of the IGBT chip 200 and play a role in dissipating heat and cooling the IGBT chip 200. At this time, the control box 20 can be made of a metal material or a plastic material.

[0049] Of course, in other embodiments, the heat dissipation block 100 can also be an integral structure with the control box 20. At this time, the heat dissipation block 100 is a convex part on the end face of the control box 20. Both the heat dissipation block 100 and the control box 20 are made of metal materials. For example, both the heat dissipation block 100 and the control box 20 are made of aluminum.

[0050] Furthermore, in the above two solutions, in order to accelerate the heat dissipation of the heat dissipation block 100, a plurality of heat dissipation fins can be provided on the side of the heat dissipation block 100 away from the IGBT chip 200, that is, the opposite side of the heat dissipation table 110. The setting of the heat dissipation fins can increase the heat dissipation area of the heat dissipation block 100, and the heat of the heat dissipation block 100 can be quickly dissipated through the air convection in the space where the heat dissipation fins are located, realizing rapid heat dissipation.

[0051] As an optional implementation, the IGBT fixed heat dissipation structure in this embodiment further includes a locking member 400. An assembly hole 3121 is provided on the pressing block 310, and a locking hole position 120 is provided on the heat dissipation block 100. The assembly hole 3121 is a through hole, and the locking hole position 120 is a threaded hole. After passing through the assembly hole 3121, the locking member 400 is threadedly connected to the locking hole position 120, thereby fixing the pressing block 310 on the heat dissipation table 110. Exemplarily, the locking member 400 can be a screw or a bolt. By tightening the locking member 400, the connection between the pressing block 310 and the heat dissipation table 110 can be ensured to be reliable, and at the same time, the elastic compression member 320 presses the IGBT chip 200, ensuring that the IGBT chip 200 is in close contact with the heat dissipation table 110 and has good heat dissipation effect. Of course, in other embodiments, the pressing block 310 can also be connected to the heat dissipation table 110 by a clamping method.

[0052] Further, a plurality of IGBT chips 200 are provided. The plurality of IGBT chips 200 are evenly spaced on the heat dissipation table 110. A plurality of mounting portions 311 and elastic compression members 320 are also provided on the pressing block 310. The mounting portions 311 and the elastic compression members 320 correspond one by one. One elastic compression member 320 is provided at each mounting portion 311, and each IGBT chip 200 abuts against at least one elastic compression member 320. A plurality of locking members 400, assembly holes 3121, and locking hole positions 120 are also provided. At least one locking member 400 is provided between every two adjacent IGBT chips 200. The locking member 400 passes through the assembly hole 3121 and the gap between two adjacent IGBT chips 200 and is correspondingly connected to a locking hole position 120, thereby realizing the detachable connection between the pressing block 310 and the heat dissipation table 110.

[0053] Exemplarily, in this embodiment, two IGBT chips 200 are taken as an example for illustration. The two IGBT chips 200 are spaced along the length direction of the pressing block 310 ( Figure 1 the Y-axis direction shown in the figure). One locking member 400 is provided. The locking member 400 is clamped between the two IGBT chips 200. After passing through the gap between the two IGBT chips 200, the locking member 400 is connected to the heat dissipation table 110. Of course, in other embodiments, more IGBT chips 200 and locking members 400 can also be provided and arranged according to needs, which will not be listed one by one here.

[0054] Furthermore, a support column 312 is provided on one side of the pressing block 310 facing the heat dissipation tabletop 110. An assembly hole 3121 penetrates through the support column 312, and the support column 312 abuts against the end face of the heat dissipation tabletop 110 on the side facing the pressing block 310. By providing the support column 312, on the one hand, it can support the middle position of the pressing block 310, so as to form a space for placing the IGBT chip 200 between the pressing block 310 and the heat dissipation tabletop 110, improving the installation stability; on the other hand, the length of the support column 312 is relatively long, which can increase the length of the cooperation between the locking member 400 and the assembly hole 3121, having a certain guiding effect and ensuring that the locking member 400 smoothly penetrates into the locking hole position 120 on the heat dissipation tabletop 110.

[0055] Continue to refer to Figure 2 and Figure 3 , the pressing block 310 in this embodiment includes two mounting portions 311 spaced apart along its length direction ( Figure 3 the Y-axis direction shown in). Each mounting portion 311 includes a positioning groove 3111 and a positioning post 3112. A positioning post 3112 is provided at the bottom of each positioning groove 3111, and the positioning post 3112 extends in the direction close to the heat dissipation tabletop 110. An elastic compression member 320 is sleeved on each positioning post 3112, and each elastic compression member 320 is used to press a IGBT chip 200. The cross-section of the positioning groove 3111 is circular, a central hole 3211 is provided at the center of the elastic compression member 320, and the positioning post 3112 penetrates through the corresponding central hole 3211 and is in interference fit with the central hole 3211. Thus, the elastic compression member 320 is sleeved and fixed on the positioning post 3112, ensuring a reliable connection between the positioning post 3112 and the elastic compression member 320 and preventing the elastic compression member 320 from falling off the positioning post 3112. Optionally, the elastic compression member 320 in this embodiment is cylindrical, and the diameter of the elastic compression member 320 is smaller than the diameter of the positioning groove 3111, and the elastic compression member 320 can be accommodated through the positioning groove 3111. Further, one side of the elastic compression member 320 facing away from the bottom of the positioning groove 3111 is a pressing plane 3212, and the pressing plane 3212 abuts against the end face of the IGBT chip 200. Since the material of the elastic compression member 320 is relatively soft and has a certain elasticity, it can achieve soft contact between the elastic compression member 320 and the IGBT chip 200, avoiding damage to the IGBT chip 200 and at the same time ensuring that the IGBT chip 200 can be closely attached to the heat dissipation tabletop 110.

[0056] Optionally, a limiting flange 313 is provided on the side of the pressing block 310 facing the heat dissipation tabletop 110. The end of the limiting flange 313 has a limiting surface for abutting against the IGBT chip 200. The position of the IGBT chip 200 can be limited by the limiting flange 313, and it is ensured as much as possible that the center of the IGBT chip 200 is directly opposite to the center of the elastic compression member 320, so as to ensure that the elastic compression member 320 presses the IGBT chip 200 tightly against the heat dissipation tabletop 110. Exemplarily, the limiting flange 313 can be provided on three sides of the pressing block 310.

[0057] Further, the IGBT fixed heat dissipation structure is arranged in the control box 20. A guiding groove 314 is provided on the pressing block 310, and the guiding groove 314 extends along the height direction of the pressing block 310 ( Figure 3 the Z-axis direction shown in the figure). A convex portion is provided on the control box 20 or the heat dissipation tabletop 110, and the convex portion is slidably connected to the guiding groove 314. The position of the pressing block 310 on the heat dissipation tabletop 110 can be limited through the cooperation of the guiding groove 314 and the convex portion, ensuring accurate positioning between the pressing block 310 and the heat dissipation tabletop 110.

[0058] Continue to refer to Figure 1 , a heat-conducting insulating sheet 500 is provided between the heat dissipation tabletop 110 and the IGBT chip 200, and both sides of the heat-conducting insulating sheet 500 are respectively attached to the heat dissipation tabletop 110 and the IGBT chip 200. The heat-conducting insulating sheet 500 can improve the heat transfer coefficient between the heat dissipation tabletop 110 and the IGBT chip 200, improving the heat dissipation effect. At the same time, the heat-conducting insulating sheet 500 can insulate between the heat dissipation tabletop 110 and the IGBT chip 200, preventing the IGBT chip 200 from being broken down. Further, a perforation 510 is provided on the heat-conducting insulating sheet 500, and the support column 312 can pass through the perforation 510 and then abut against the heat dissipation tabletop 110. The locking member 400 passes through the assembly hole 3121 on the support column 312 and the perforation 510 and then locks with the heat dissipation block 100.

[0059] More preferably, in this embodiment, the perforation 510 on the heat-conducting insulating sheet 500 is in a water droplet shape. The side with a larger opening allows the support column 312 and the locking member 400 to pass through, and the side with a smaller opening allows the connection line to pass through. The connection line is electrically connected to the IGBT chip 200 to realize the connection between the IGBT chip 200 and the external circuit.

[0060] Refer to Figure 4, this embodiment also provides a PTC heater, including an IGBT fixed heat dissipation structure, a circuit board 10, and a control box 20. The circuit board 10 and the IGBT fixed heat dissipation structure are arranged inside the control box 20. A wiring socket 11 is provided on the circuit board 10. The wiring terminal of the IGBT chip 200 passes out from a side of the pressing block 310 where there is no limiting flange 313 and is connected to the wiring socket 11, thereby realizing the electrical connection of the IGBT chip 200. In addition, due to the arrangement of the elastic compression member 320 and the heat-conducting insulating sheet 500, the creepage distance and creepage clearance of the IGBT chip 200 are relatively large, the IGBT chip 200 is not easily broken down, and the safety is high.

[0061] Embodiment Two

[0062] This embodiment provides an IGBT fixed heat dissipation structure, which is different from the IGBT fixed heat dissipation structure in Embodiment One in that: the installation structure between the pressing block 310 and the elastic compression member 320 in this embodiment is different.

[0063] As Figures 5-7 shown, this embodiment provides an IGBT fixed heat dissipation structure, including a heat dissipation block 100, an IGBT chip 200, and a pressing assembly 300. The heat dissipation block 100 has a heat dissipation table surface 110. The IGBT chip 200 is placed on the heat dissipation table surface 110, and the pressing assembly 300 presses the IGBT chip 200 on the heat dissipation table surface 110.

[0064] The pressing assembly 300 includes a pressing block 310 and an elastic compression member 320. The installation portion 311 of the pressing block 310 includes a positioning groove 3111 and an installation hole 3113. The positioning groove 3111 is located on a side of the pressing block 310 close to the heat dissipation table surface 110, and the installation hole 3113 is arranged at the bottom of the positioning groove 3111. The elastic compression member 320 includes an integrally formed main body portion 321 and a fixing portion 322. The fixing portion 322 passes through and is fixed in the installation hole 3113, and the main body portion 321 is accommodated in the positioning groove 3111. It should be noted that the fixing portion 322 is cylindrical, the installation hole 3113 is a circular hole, the diameter of the circular hole is smaller than the outer diameter of the fixing portion 322, and the fixing portion 322 is in interference fit with the inner wall of the installation hole 3113, thereby stably fixing the elastic compression member 320 on the pressing block 310 and realizing a reliable connection between the two.

[0065] Further, the main body portion 321 is cylindrical, the cross-section of the positioning groove 3111 is circular, the main body portion 321 can be accommodated in the positioning groove 3111, a central hole 3211 is provided at the center of the main body portion 321, and the central hole 3211 can achieve weight reduction of the elastic compression member 320, while reducing consumables and lowering costs. The end of the main body portion 321 facing the heat dissipation table 110 is a pressing plane 3212, which abuts against the end face of the IGBT chip 200 through the pressing plane 3212. Since the material of the elastic compression member 320 is soft and has a certain elasticity, a soft contact between the elastic compression member 320 and the IGBT chip 200 can be achieved, avoiding damage to the IGBT chip 200, and at the same time ensuring that the IGBT chip 200 can be closely attached to the heat dissipation table 110. In addition, the elastic compression member 320 can be made of materials such as rubber and silica gel. Through the elastic compression member 320, the IGBT chip 200 and the pressing block 310 are insulated, and the creepage distance and creepage clearance of the IGBT chip 200 are increased, making it not easily breakdown.

[0066] As an alternative embodiment, multiple IGBT chips 200 in this embodiment can be provided, and the multiple IGBT chips 200 are evenly spaced on the heat dissipation table 110. Correspondingly, the positioning grooves 3111, the mounting holes 3113, and the elastic compression members 320 are also provided in multiple numbers, and the positioning grooves 3111, the mounting holes 3113, the elastic compression members 320, and the IGBT chips 200 correspond one by one, and each elastic compression member 320 is used to press one IGBT chip 200. Exemplarily, in this embodiment, three IGBT chips 200 are taken as an example for illustration. The three IGBT chips 200 are arranged in sequence along a straight line. Furthermore, the multiple positioning grooves 3111 on the pressing block 310 can be sequentially arranged along its length direction, and one mounting hole 3113 is provided at the bottom of each positioning groove 3111. Among them, the mounting hole 3113 can be a blind hole or a through hole. Here, the mounting hole 3113 is taken as a through hole for illustration.

[0067] The IGBT fixed heat dissipation structure further includes a locking member 400. An assembly hole 3121 is provided on the pressing block 310, and a locking hole position 120 is provided on the heat dissipation block 100. Among them, the assembly hole 3121 is a through hole, and the locking hole position 120 is a threaded hole. The locking member 400 passes through the assembly hole 3121 and is threadedly connected to the locking hole position 120, thereby fixing the pressing block 310 on the heat dissipation table 110. Exemplarily, the locking member 400 can be a screw or a bolt. By tightening the locking member 400, the connection between the pressing block 310 and the heat dissipation table 110 can be ensured to be reliable, and at the same time, the elastic compression member 320 presses the IGBT chip 200, ensuring that the IGBT chip 200 is closely attached to the heat dissipation table 110 and the heat dissipation effect is good. Of course, in other embodiments, the pressing block 310 can also be connected to the heat dissipation table 110 by a clamping method.

[0068] Further, in this embodiment, two support columns 312 are also provided on the side of the pressing block 310 facing the heat dissipation table top 110. The two support columns 312 are respectively arranged at both ends in the length direction ( Figures 5-7 the Y-axis direction) of the pressing block 310. An assembly hole 3121 penetrating through the support column 312 is provided on each support column 312. The support column 312 is used to abut against the side of the heat dissipation table top 110 facing the pressing block 310. Two locking members 400 are provided. Two locking holes 120 are also provided on the heat dissipation block 100. The two locking members 400 respectively pass through the assembly holes 3121 at both ends in the length direction of the pressing block 310 and are threadedly connected to the locking holes 120 on the heat dissipation block 100. By providing the support column 312, on the one hand, the pressing block 310 can be supported, so that a space for placing the IGBT chip 200 is formed between the pressing block 310 and the heat dissipation table top 110, improving the installation stability; on the other hand, the length of the support column 312 is relatively long, which can increase the length of the cooperation between the locking member 400 and the assembly hole 3121, having a certain guiding effect to ensure that the locking member 400 smoothly penetrates into the locking hole 120 on the heat dissipation table top 110.

[0069] Of course, in other embodiments, when the number of IGBT chips 200 is larger, one or more support columns 312 can also be arranged at the middle position in the length direction of the pressing block 310. Through holes 3121 can also be provided on the support columns 312. A locking hole 120 is provided on the heat dissipation block 100 corresponding to each assembly hole 3121. A locking member 400 that cooperates with each other is provided in each group of assembly holes 3121 and locking holes 120. Thus, the middle position in the length direction of the pressing block 310 is also connected to the heat dissipation table top 110, improving the installation stability of the pressing block 310. At the same time, it also avoids a large gap between the pressing block 310 and the IGBT chip 200, preventing the elastic compression member 320 from not being able to tightly press the IGBT chip 200, and improving the pressing effect of the elastic compression member 320 on the IGBT chip 200.

[0070] This embodiment also provides a PTC heater, including the above IGBT fixed heat dissipation structure and a circuit board 10. The pressing assembly 300 of the IGBT fixed heat dissipation structure presses the IGBT chip 200 onto the circuit board 10. Due to the setting of the elastic compression member 320, the creepage distance and creepage clearance of the IGBT chip 200 are relatively large, and the IGBT chip 200 is not easily broken down, with high safety.

[0071] The remaining structures in this embodiment are the same as those in the first embodiment and will not be elaborated here one by one.

[0072] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present utility model. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present utility model shall be included in the protection scope of the claims of the present utility model.

Claims

1. An IGBT fixed heat dissipation structure, characterized in that, Comprising: A heat sink block (100) having a heat dissipation tabletop (110); An IGBT chip (200) disposed on the heat dissipation tabletop (110); A pressing assembly (300) including a pressing block (310) and an elastic compression member (320). The projection of the pressing block (310) on the heat dissipation tabletop (110) at least partially coincides with the projection of the IGBT chip (200) on the heat dissipation tabletop (110). An installation portion (311) is provided on the side of the pressing block (310) facing the heat dissipation tabletop (110). The elastic compression member (320) is connected to the installation portion (311). The pressing block (310) is connected to the heat dissipation tabletop (110). The elastic compression member (320) presses the IGBT chip (200) against the heat dissipation tabletop (110) by an elastic force, and the elastic compression member (320) is insulated from the IGBT chip (200).

2. The IGBT fixed heat dissipation structure according to claim 1, characterized in that The IGBT fixed heat dissipation structure further includes a locking member (400). An assembly hole (3121) is provided on the pressing block (310), and a locking hole position (120) is provided on the heat sink block (100). The locking member (400) passes through the assembly hole (3121) and is connected to the locking hole position (120).

3. The IGBT fixed heat dissipation structure according to claim 2, characterized in that, A plurality of the locking members (400), the assembly holes (3121), and the locking hole positions (120) are provided, and the locking members (400), the assembly holes (3121), and the locking hole positions (120) correspond to each other one by one. Each locking member (400) passes through the corresponding assembly hole (3121) and is connected to one locking hole position (120).

4. The IGBT fixed heat dissipation structure according to claim 2, characterized in that, A support column (312) is further provided on the side of the pressing block (310) facing the heat dissipation tabletop (110). The assembly hole (3121) penetrates through the support column (312), and the support column (312) abuts against the side of the heat dissipation tabletop (110) facing the pressing block (310).

5. The IGBT fixed heat dissipation structure according to claim 1, characterized in that A plurality of IGBT chips (200) are provided. The plurality of IGBT chips (200) are arranged at intervals on the heat dissipation tabletop (110). A plurality of installation portions (311) and elastic compression members (320) are also provided on the pressing block (310). The installation portions (311) and the elastic compression members (320) correspond to each other one by one. One elastic compression member (320) is provided at each installation portion (311), and each IGBT chip (200) abuts against at least one elastic compression member (320).

6. The IGBT fixed heat dissipation structure according to claim 5, characterized in that, The installation portion (311) includes a positioning groove (3111) and a positioning post (3112). The positioning post (3112) is provided at the bottom of the positioning groove (3111) and extends in a direction close to the heat dissipation tabletop (110). A central hole (3211) is provided at the center of the elastic compression member (320). The positioning post (3112) passes through and is fixed in the central hole (3211), and the positioning groove (3111) is used to accommodate the elastic compression member (320).

7. The IGBT fixed heat dissipation structure according to claim 5, characterized in that, The installation part (311) includes a positioning groove (3111) and an installation hole (3113). The installation hole (3113) is arranged at the bottom of the positioning groove (3111). The elastic compression member (320) includes an integrally formed main body part (321) and a fixing part (322). The fixing part (322) passes through and is fixed in the installation hole (3113), and the positioning groove (3111) is used to accommodate the main body part (321).

8. The IGBT fixed heat dissipation structure according to any one of claims 1-7, characterized in that One side of the pressing block (310) facing the heat dissipation table surface (110) is provided with a limiting flange (313). The end of the limiting flange (313) has a limiting surface, and the limiting surface is used to abut against the IGBT chip (200).

9. The IGBT fixed heat dissipation structure according to any one of claims 1-7, characterized in that, The IGBT fixed heat dissipation structure is arranged in the control box (20). The pressing block (310) is provided with a guiding groove (314). The control box (20) or the heat dissipation table surface (110) is provided with a protruding part, and the protruding part is slidably connected with the guiding groove (314).

10. The IGBT fixed heat dissipation structure according to any one of claims 1-7, characterized in that, A heat conductive insulating sheet (500) is arranged between the heat dissipation table surface (110) and the IGBT chip (200). Both sides of the heat conductive insulating sheet (500) are respectively attached to the heat dissipation table surface (110) and the IGBT chip (200).

11. A PTC heater, characterized in that, It includes the IGBT fixed heat dissipation structure according to any one of claims 1-10.

Images