Variable frequency controller capable of comprehensively protecting power tube

Abstract

The utility model relates to a variable frequency controller capable of comprehensively protecting a power tube in the controller field, comprising a housing, a PCB assembly and an EMC assembly, the EMC assembly is electrically connected with the PCB assembly, the housing is provided with a PCB accommodating groove, the PCB assembly is arranged in the PCB accommodating groove, the PCB assembly comprises a main control circuit board, a power tube, a support, a capacitor, a resistor, a bridge rectifier and a heat dissipation block, and the main control circuit board is electrically connected with the support. The capacitor, the resistor and the bridge rectifier are welded on the surface of the main control circuit board, the surface of the support is provided with a positioning groove used for installing the power tube, the positioning groove is internally provided with a through hole, the support is installed on the surface of the main control circuit board, the power tube is horizontally installed in the positioning groove, and a pin of the power tube is bent towards the through hole, penetrates through the through hole and then is welded with the main control circuit board. The PCB containing groove is internally provided with the sealing glue, the sealing glue can completely immerse the power tube, the good electrical insulation performance is achieved, the insulation resistance between the main control circuit board and the power tube, between the capacitor and the resistor and between the main control circuit board and the bridge rectifier can be remarkably improved, and the risks of leakage current and metal migration are reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of controller, especially variable frequency controller of comprehensive protection power tube. BACKGROUND

[0002] The controller for electric tool is a device for controlling mechanical quantity, working sequence and operation mode by controlling electric quantity of electric tool, which is mainly connected with brushless motor in electric tool. With the continuous progress of lithium battery technology and the continuous change of consumer demand, the electric tool industry presents the development trend of cordless, lithium battery, integration and intelligentization. The controller as the core component of electric tool plays a key role in promoting the development of this trend.

[0003] As shown in Figure 1 The structure of the controller for electric tool on the market includes PCB assembly 1, switch 3 and EMC assembly 2, the EMC assembly 2 is connected with the PCB assembly 1 through two input lines, the motor is connected with the PCB assembly 1 through three output lines, and the switch 3 is connected with the PCB assembly 1 through a wire harness.

[0004] As shown in Figure 2 In the existing PCB assembly 1, the main control circuit board 5 is arranged in the shell, the power tube 4 is vertically installed on the main control circuit board 5, the upper half of the power tube 4 is higher than the opening of the shell, and the upper half of the power tube 4 is often provided with an exposed part for heat dissipation. When the glue is sealed, the glue 6 cannot immerse the exposed part of the power tube 4, so that water mist or iron powder is easily sprayed on the power tube 4 in the process of use, which affects normal work and causes short circuit to lead to breakdown between tubes. INVENTION CONTENTS

[0005] In order to overcome the defects of the prior art, the utility model provides the variable frequency controller of comprehensive protection power tube, which can effectively solve the technical problem that the power tube cannot be completely sealed and protected.

[0006] The technical scheme adopted by the utility model to solve its technical problems is:

[0007] The frequency conversion controller capable of comprehensively protecting the power tube comprises a shell, a PCB assembly and an EMC assembly, the EMC assembly is electrically connected with the PCB assembly, the shell is provided with a PCB accommodating groove, the PCB assembly is arranged in the PCB accommodating groove, the PCB assembly comprises a main control circuit board, power tubes, a support, a capacitor, a resistor, a bridge and a heat dissipation block, the capacitor, the resistor and the bridge are welded on the surface of the main control circuit board, the main control circuit board can be placed in the PCB accommodating groove, the power tubes are more than two, the surface of the support is provided with positioning grooves for mounting the power tubes, the positioning grooves are provided with through holes, the support is mounted on the surface of the main control circuit board, the power tubes are horizontally mounted in the positioning grooves, the pins of the power tubes are bent towards the through holes and welded with the main control circuit board after passing through the through holes, the surface of the heat dissipation block is attached to the surface of the power tube, heat exchange is generated between the heat dissipation block and the power tube, the PCB accommodating groove is provided with sealing glue, the sealing glue can completely immerse the power tube, has good electrical insulation performance, can significantly improve the insulation resistance between the main control circuit board and the power tube, the capacitor, the resistor and the bridge, and reduce the risk of leakage current and metal migration.

[0008] Further, the edge of the heat dissipation block is provided with a step, the support is provided with a positioning plate, the positioning plate is provided with a buckle part, the buckle part can be buckled with the surface of the step, so that the position of the heat dissipation block is fixed, the bottom of the heat dissipation block is tightly attached to the surface of the power tube, and it is ensured that the heat of the power tube can be transmitted to the heat dissipation block.

[0009] Further, the surface of the bridge is provided with a heat dissipation fin, the bridge is vertically arranged on the main control circuit board, the bottom surface of the heat dissipation fin is attached to the side wall of the bridge, so that the sealing glue cannot immerse the bridge and the heat dissipation fin to cause heat dissipation failure.

[0010] Further, the shell is also provided with an EMC accommodating groove, the EMC assembly is arranged in the EMC accommodating groove, the EMC accommodating groove is also provided with sealing glue, the sealing glue can effectively fix the elements on the circuit board, prevent the elements from falling off or being damaged due to vibration, impact or falling, and form a protective film to prevent the circuit board from being eroded by external environment such as dust, moisture and chemical solvents, thereby improving the weather resistance and service life of the EMC assembly.

[0011] Further, the shell is provided with a conductive wiring cavity, the conductive wiring cavity is provided with input terminals and output terminals, the two ends of the input terminals extend into the EMC accommodating groove and the PCB accommodating groove and are connected with the PCB assembly and the EMC assembly respectively, and the output terminals extend into the PCB accommodating groove and are connected with the main control circuit board, so that the connection between the EMC assembly and the PCB assembly is more firm and reliable.

[0012] Further, the support is mounted on the main control circuit board by bolts.

[0013] Compared with the prior art, the power tube is immersed in the glue during the sealing process, the power tube is not in contact with air, better electrical insulation and mechanical protection are provided, water mist or iron powder is effectively prevented from falling on the power tube, the surface of the heat dissipation block is attached to the surface of the power tube, the heat dissipation efficiency of the power tube is not affected, heat can be timely and effectively conducted away through the heat dissipation plate, the heat dissipation efficiency of the power tube after packaging is maintained, and the working stability and service life of the power tube are further improved. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a structural schematic view of the prior art;

[0015] Figure 2 It is a schematic view of a PCB assembly in the prior art;

[0016] Figure 3 It is an installation schematic view of a power tube and a main control circuit board in the prior art;

[0017] Figures 1-3 Reference numerals: 1-PCB assembly, 2-EMC assembly, 3-switch, 4-power tube, 5-main control circuit board, 6-glue.

[0018] Figure 4 It is a structural schematic view of the utility model;

[0019] Figure 5 It is a structural schematic view of a PCB assembly in the utility model;

[0020] Figure 6 It is an exploded view of a PCB assembly in the utility model;

[0021] Figure 7 It is a structural schematic view of a support in the utility model;

[0022] Figures 4-7 Reference numerals: 1-housing, 2-PCB assembly, 201-main control circuit board, 202-power tube, 203-support, 2031-positioning groove, 2032-through hole, 2033-positioning plate, 2034-buckling part, 204-capacitor, 205-bridge stack, 206-heat dissipation block, 2061-step, 207-radiator, 3-EMC assembly, 4-sealing glue. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model.

[0024] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model. Figures 3-7 The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model.

[0025] The frequency conversion controller of the comprehensively protectable power tube 202 comprises an outer shell 1, a PCB assembly 2 and an EMC assembly 3, the EMC assembly 3 is electrically connected with the PCB assembly 2, a PCB accommodating groove is formed in the outer shell 1, the PCB assembly 2 is arranged in the PCB accommodating groove, the PCB assembly 2 comprises a main control circuit board 201, a power tube 202, a support 203, a capacitor 204, a bridge stack 205 and a heat dissipation block 206, the capacitor 204 and the bridge stack 205 are welded on the surface of the main control circuit board 201, the main control circuit board 201 can be placed in the PCB accommodating groove, six power tubes 202 are arranged, a positioning groove 2031 for mounting the power tube 202 is formed in the surface of the support 203, a through hole 2032 is formed in the positioning groove 2031, the support 203 is mounted on the main control circuit board 201 through bolts, the power tube 202 is horizontally arranged in the positioning groove 2031, the pin of the power tube 202 is bent towards the through hole 2032 and is welded with the main control circuit board 201 after passing through the through hole 2032, the surface of the heat dissipation block 206 is attached to the surface of the power tube 202, heat exchange is generated between the heat dissipation block 206 and the power tube 202, a sealing glue 4 is arranged in the PCB accommodating groove, the sealing glue 4 can completely immerse the power tube 202, has good electrical insulation performance, can significantly improve the insulation resistance between the main control circuit board 201 and the power tube 202, the capacitor 204 and the bridge stack 205, reduces the risk of leakage current and metal migration.

[0026] The edge of the heat dissipation block 206 is provided with a step 2061, the support 203 is provided with a positioning plate 2033, the positioning plate 2033 is provided with a buckle part 2034, the buckle part 2034 can be buckled with the surface of the step 2061, so that the position of the heat dissipation block 206 is fixed, the bottom of the heat dissipation block 206 is tightly attached to the surface of the power tube 202, and it is ensured that the heat of the power tube 202 can be transmitted to the heat dissipation block 206, the surface of the bridge stack 205 is provided with a heat dissipation fin 207, the bridge stack 205 is vertically arranged on the main control circuit board 201, the bottom surface of the heat dissipation fin 207 is attached to the side wall of the bridge stack 205, and the sealing glue 4 is prevented from immersing the bridge stack 205 and the heat dissipation fin 207 to cause heat dissipation failure.

[0027] The frequency conversion controller of the fully-protected power tube 202 in the embodiment, the power tube 202 is installed on the main control circuit board 201, the power tube 202 is horizontally arranged in the support 203, the glue can completely immerse the whole power tube 202 when the glue is sealed 4, the power tube 202 is not contacted with air, better electrical insulation and mechanical protection can be provided, the water mist or iron powder falling on the power tube 202 is effectively avoided, meanwhile, the surface of the heat dissipation block 206 is attached to the surface of the power tube 202, the heat dissipation efficiency of the power tube 202 is not affected, the heat can be timely and effectively conducted out through the heat dissipation plate, the heat dissipation efficiency of the power tube 202 after encapsulation is maintained, and the working stability and service life of the power tube 202 are further improved.

[0028] The EMC accommodating groove is further arranged on the shell 1, the EMC component 3 is arranged in the EMC accommodating groove, the EMC accommodating groove is also provided with the sealing glue 4, the sealing glue 4 can effectively fix the elements on the circuit board, prevent the elements from falling off or being damaged due to vibration, impact or falling, the sealing glue 4 layer can form a protective film, prevent the circuit board from being eroded by external environment such as dust, moisture and chemical solvent, thereby improving the weather resistance and service life of the EMC component 3, the conductive wiring cavity is arranged in the shell 1, the input terminal and the output terminal are arranged in the conductive wiring cavity, the two ends of the input terminal extend into the EMC accommodating groove and the PCB accommodating groove, and are connected with the PCB component 2 and the EMC component 3 respectively, the output terminal extends into the PCB accommodating groove and is connected with the main control circuit board 201, so that the connection between the EMC component 3 and the PCB component 2 is more firm and reliable, the EMC component 3 includes the control circuit board, the common mode inductor and the capacitor 204, the common mode inductor and the capacitor 204 are welded on the control circuit board, the end of the connecting piece away from the input terminal is inserted into the control circuit board, the functions and working principles of the PCB component 2 and the EMC component 3 are well known in the art and are conventional technical means, the relevant information can be known or easily obtained by the person skilled in the art, and will not be described again.

[0029] It is apparent for those skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all aspects as illustrative and not restrictive, the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and range of equivalents of the elements of the claims are intended to be embraced by the present application. Any reference signs in the claims should not be considered as limiting the claims involved.

Claims

1. A frequency converter controller capable of providing comprehensive protection for power transistors, comprising a housing, a PCB assembly, and an EMC assembly, wherein the EMC assembly is electrically connected to the PCB assembly, characterized in that: The outer casing is provided with a PCB receiving slot, and the PCB assembly is disposed in the PCB receiving slot. The PCB assembly includes a main control circuit board, power transistors, a bracket, capacitors, resistors, a bridge rectifier, and a heat sink. The capacitors, resistors, and bridge rectifier are soldered to the surface of the main control circuit board, which can be placed in the PCB receiving slot. There are two or more power transistors. The surface of the bracket is provided with positioning slots for mounting the power transistors. The positioning slots are provided with through holes. The bracket is mounted on the surface of the main control circuit board, and the power transistors are horizontally mounted in the positioning slots. The leads of the power transistors are bent towards the through holes and passed through the through holes before being soldered to the main control circuit board. The surface of the heat sink is in contact with the surface of the power transistors, and heat exchange occurs between the heat sink and the power transistors. The PCB receiving slot is provided with sealant, which can completely immerse the power transistors.

2. The frequency converter controller with comprehensive protection for power transistors according to claim 1, characterized in that: The heat sink has a step at its edge, and a positioning plate is provided on the bracket. The positioning plate has a buckle that can engage with the surface of the step, thereby fixing the position of the heat sink.

3. The frequency converter controller with comprehensive protection for power transistors according to claim 1, characterized in that: The bridge rectifier is provided with heat sinks on its surface and is vertically mounted on the main control circuit board. The bottom surface of the heat sinks is attached to the side wall of the bridge rectifier.

4. The frequency converter controller with comprehensive protection for power transistors according to any one of claims 1-3, characterized in that: The outer casing is also provided with an EMC receiving groove, in which the EMC component is disposed, and the EMC receiving groove is also provided with sealant.

5. The frequency converter controller with comprehensive protection for power transistors according to claim 4, characterized in that: The housing contains a conductive wiring cavity, which contains an input terminal and an output terminal. The two ends of the input terminal extend into the EMC receiving groove and the PCB receiving groove, and are connected to the PCB assembly and the EMC assembly, respectively. The output terminal extends into the PCB receiving groove and is connected to the main control circuit board.

6. The frequency converter controller with comprehensive protection for power transistors according to any one of claims 1-3, characterized in that: The bracket is installed to the main control circuit board by bolts.

Images