A multi-duct cooling device and power tool

Abstract

The utility model discloses a kind of multi-air duct heat sink and electric tool, the multi-air duct heat sink includes the shell with the heat dissipation passage formed inside, and the line board controller in the heat dissipation passage, driving motor and heat dissipation fan, air inlet on shell includes first air inlet, second air inlet, line board controller is arranged between first air inlet and second air inlet, driving motor is arranged between second air inlet and air outlet, heat dissipation fan is arranged between second air inlet and driving motor, heat dissipation fan works fan and the wind inhaled from first air inlet and second air inlet is blown to driving motor direction along heat dissipation passage, and the wind inhaled from first air inlet can be heat exchanged with line board controller in the process of moving towards heat dissipation fan.The multi-air duct heat sink can simultaneously cool driving motor and line board controller, enhance the heat dissipation effect of electric tool provided with the multi-air duct heat sink, prolong the service life of electric tool.

Description

Technical Field

[0001] This utility model relates to the field of power tools, and in particular to a multi-channel heat dissipation device and a power tool. Background Technology

[0002] Power tools such as polishing machines, grinding machines, and cutting machines, which require motors to drive the workpiece to rotate at high speeds, generate a lot of heat inside. If the heat cannot be dissipated in time, it can easily affect their performance.

[0003] Most existing power tool cooling devices only target the cooling of the drive motor and lack effective cooling for the circuit board controller. During operation, if the circuit board controller overheats, it can burn out the circuitry or even cause the power tool to crash, thus affecting its lifespan. Summary of the Invention

[0004] This utility model addresses the shortcomings of existing technologies by providing a multi-channel heat dissipation device and a power tool. The multi-channel heat dissipation device can simultaneously dissipate heat from the drive motor and the circuit board controller, thereby enhancing the heat dissipation effect of the power tool and extending its service life.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A multi-channel heat dissipation device includes a housing with internal heat dissipation channels, and a circuit board controller, a drive motor, and a cooling fan respectively installed within the heat dissipation channels. The housing has an air inlet and an air outlet respectively connected to the heat dissipation channels. The air inlet includes a first air inlet channel and a second air inlet channel arranged between the first air inlet channel and the air outlet. The circuit board controller is arranged between the first air inlet channel and the second air inlet channel. The drive motor is arranged between the second air inlet channel and the air outlet and is electrically connected to the circuit board controller. The cooling fan is arranged between the second air inlet channel and the drive motor. When the cooling fan is working, it blows the air drawn in from the first air inlet channel and the second air inlet channel along the heat dissipation channels toward the drive motor. The air drawn in from the first air inlet channel can exchange heat with the circuit board controller as it moves toward the cooling fan.

[0007] Preferably, the inner wall of the housing is provided with a controller mounting base, the circuit board controller is mounted on the controller mounting base, and after installation, a moving channel is formed between the circuit board controller and the housing for the air drawn in from the first air inlet to move toward the cooling fan, the moving channel being configured as part of the heat dissipation channel.

[0008] Preferably, a moving channel is formed between the upper side of the circuit board controller and the housing, and between the lower side of the circuit board controller and the housing, for the air drawn in from the first air inlet to move toward the cooling fan.

[0009] Preferably, the heat dissipation channel includes a first channel section arranged on the side of the circuit board controller away from the cooling fan and a second channel section arranged on the side of the circuit board controller closer to the cooling fan. The first air inlet duct and the movable air ducts arranged on the upper and lower sides of the circuit board controller are respectively connected to the first channel section, and the second air inlet duct is connected to the second channel section.

[0010] Preferably, the housing includes a main outer shell and a gripping outer shell connected to one side of the main outer shell. The heat dissipation channel is arranged along the interior of the main outer shell and the gripping outer shell. The drive motor is installed inside the main outer shell. The circuit board controller is installed inside the gripping outer shell. The first air inlet is located at the rear of the gripping outer shell, and the second air inlet is located at the front of the gripping outer shell.

[0011] Preferably, the housing includes a first half-shell and a second half-shell that are detachably connected to each other. The main body housing and the gripping housing are respectively formed by the first half-shell and the second half-shell. The first air inlet and the second air inlet are respectively arranged on the lower side of the circuit board controller, and the first air inlet is arranged on the first half-shell and / or the second half-shell, and the second air inlet is arranged on the first half-shell and / or the second half-shell. The cooling fan is arranged at an upward angle so that it can blow the air drawn in from the first air inlet and the second air inlet towards the drive motor and its upper side when working.

[0012] Preferably, the drive motor is arranged longitudinally and includes a motor body installed longitudinally in a heat dissipation channel and a drive shaft rotatably connected in the motor body. The upper end of the drive shaft protrudes from the upper end of the motor body and is rotatably connected to the main body shell through a first bearing installed in the heat dissipation channel. The cooling fan can blow air from the first air inlet and the second air inlet towards the motor body and the first bearing when the motor is in operation.

[0013] Preferably, the device further includes a working component arranged near the air outlet. The working component includes an eccentric structure that is driven by the drive shaft of the drive motor, a polishing disc that is rotatably connected to the lower side of the eccentric structure off-axis from the drive shaft, and a fan blade structure mounted on the eccentric structure. The air outlet includes a first air outlet duct arranged opposite to the back of the polishing disc. When the working component is working, the fan blade structure rotates with the eccentric structure and fans the air drawn in from the upper side of the fan blade structure to blow it along the heat dissipation duct toward the back of the polishing disc.

[0014] Preferably, the grip shell and the main shell are arranged at an angle, the second air inlet is located at the angle connection between the grip shell and the main shell, and has a first air inlet path toward the grip shell and a second air inlet path toward the main shell; the heat dissipation channel includes a third channel section arranged between the second air inlet and the fan blade structure, and the second air inlet is connected to the third channel section along the second air inlet path.

[0015] This utility model also provides an electric tool, including the multi-channel heat dissipation device as described above.

[0016] The beneficial effects achieved by this utility model are as follows:

[0017] The multi-airflow cooling device provided by this utility model features a multi-airflow design, with the circuit board controller positioned between the first and second airflow inlets. This allows the warm air generated after heat exchange between the cold air drawn in through the first airflow inlet and the circuit board controller, along with the cold air drawn in through the second airflow inlet, to be circulated to the drive motor via cooling fans. This design effectively cools both the circuit board controller and the drive motor simultaneously, preventing overheating of the circuit board controller that could lead to circuit burnout or system crashes. It significantly improves the airflow utilization rate within the cooling channels, enhances the heat dissipation effect of power tools equipped with this multi-airflow cooling device, and extends the service life of the power tools. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an electric tool according to an embodiment of the present invention.

[0019] Figure 2 This is an exploded view of a power tool according to an embodiment of the present invention.

[0020] Figure 3 This is a partial structural diagram of a power tool according to an embodiment of the present invention. Figure 1 .

[0021] Figure 4 This is a partial structural diagram of a power tool according to an embodiment of the present invention. Figure 2 .

[0022] Figure 5 This is a partial structural diagram of a power tool according to an embodiment of the present invention. Figure 3 .

[0023] Figure label:

[0024] Housing 1, air inlet 11, first air inlet duct 111, second air inlet duct 112, air outlet 12, first air outlet duct 121, second air outlet duct 122, baffle plate 13, bearing mounting base 131, motor mounting base 14, motor fixing sleeve 15, fan mounting base 16, controller mounting base 17, main body shell 18, grip shell 19, first half shell 1a, second half shell 1b;

[0025] Working component 2, polishing disc 21, eccentric structure 22, eccentric block 221, counterweight block 222, fan blade structure 23, fan blade section 231, fan blade 2311, upper fastening part 232, lower fastening part 233, counterweight channel 234;

[0026] Drive motor 3, motor body 31, drive shaft 32, first bearing 33, second bearing 34;

[0027] Cooling fan 4, fan blade assembly 41, fan bracket 42;

[0028] 5. Circuit board controller; 6. Switching components; 7. Speed ​​regulating components;

[0029] Heat dissipation channel 10, first channel segment 101, second channel segment 102, third channel segment 103, interval channel 104, air passage channel 105, and moving channel 106;

[0030] First vertical axis L1, first horizontal axis L2, first air intake path S1, second air intake path S2. Detailed Implementation

[0031] like Figures 1-5As shown in the figure, as an embodiment of the present invention, a power tool including a multi-channel heat dissipation device is provided. The multi-channel heat dissipation device includes a housing 1 with a heat dissipation channel 10 formed inside, and a circuit board controller 5, a drive motor 3, and a cooling fan 4 respectively installed within the heat dissipation channel 10. The housing 1 has an air inlet 11 and an air outlet 12 respectively communicating with the heat dissipation channel 10. The air inlet 11 includes a first air inlet channel 111 and a second air inlet channel 112 arranged between the first air inlet channel 111 and the air outlet 12. The circuit board controller 5 is arranged between the first air inlet channel 111 and the second air inlet channel 112. The drive motor 3 is arranged between the second air inlet channel 112 and the air outlet 12 and is electrically connected to the circuit board controller 5. The cooling fan 4 is arranged between the second air inlet duct 112 and the drive motor 3. When the cooling fan 4 is working, it blows the air drawn in from the first air inlet duct 111 and the second air inlet duct 112 along the heat dissipation channel 10 toward the drive motor 3. The air drawn in from the first air inlet duct 111 can exchange heat with the circuit board controller 5 as it moves toward the cooling fan 4. The multi-airflow cooling device of this embodiment, through its multi-airflow design, with the circuit board controller 5 arranged between the first airflow duct 111 and the second airflow duct 112, allows the cold air drawn in through the first airflow duct 111 to exchange heat with the circuit board controller 5 to form warm air, and the cold air drawn in through the second airflow duct 112 to be fanned by the cooling fan 4 to the drive motor 3. This enables the circuit board controller 5 to be cooled by cold air, while the drive motor 3 is cooled by both cold and warm air. This effectively cools both the circuit board controller 5 and the drive motor 3, preventing the circuit board controller 5 from overheating and causing circuit burnout or system crashes. It greatly improves the airflow utilization rate within the cooling channel 10, enhances the heat dissipation effect of the power tool equipped with this multi-airflow cooling device, and extends the service life of the power tool.

[0032] like Figure 3 As shown, in this embodiment, a controller mounting base 17 protrudes from the inner wall of the housing 1. The circuit board controller 5 is mounted on the controller mounting base 17. After installation, a moving channel 106 is formed between the circuit board controller 5 and the housing 1, allowing air drawn in from the first air inlet duct 111 to move towards the cooling fan 4. The moving channel 106 is part of the structure of the cooling channel 10, ensuring that the air drawn in from the first air inlet duct 111 can both cool the circuit board controller 5 and flow along the cooling channel 10 towards the cooling fan 4 to continue cooling the drive motor 3. A fan mounting base 16 protrudes from the inner wall of the housing 1. The cooling fan 4 includes a fan bracket 42 mounted on the fan mounting base 16 and a fan blade assembly 41 rotatably connected to the fan bracket 42. The fan bracket 42 supports the rotation of the fan blade assembly 41. The fan bracket 42 and the fan blade assembly 41 are an integral structure, facilitating the installation or removal of the cooling fan 4.

[0033] In this embodiment, movable channels 106 are formed between the upper side of the circuit board controller 5 and the housing 1, and between the lower side of the circuit board controller 5 and the housing 1, respectively, for the air drawn in from the first air inlet duct 111 to move toward the cooling fan 4. This allows the air drawn in from the first air inlet duct 111 to blow on the upper and lower sides of the circuit board controller 5, increasing the contact area between the air and the circuit board controller 5 and improving the heat dissipation efficiency of the circuit board controller 5.

[0034] In this embodiment, the heat dissipation channel 10 includes a first channel section 101 arranged on the side of the circuit board controller 5 away from the cooling fan 4, and a second channel section 102 arranged on the side of the circuit board controller 5 close to the cooling fan 4. The first air inlet duct 111 and the moving channels 106 arranged on the upper and lower sides of the circuit board controller 5 are respectively connected to the first channel section 101. The second air inlet duct 112 is connected to the second channel section 102, so that the air drawn in from the first air inlet duct 111 can flow into the moving channels 106 on the upper and lower sides of the circuit board controller 5 through the first channel section 101, and flow to the second channel section 102 through the two moving channels 106 to converge, so as to facilitate the unified fan direction of the cooling fan 4 to drive the motor 3.

[0035] like Figure 1 , Figure 2 As shown, in this embodiment, the housing 1 includes a main outer shell 18 and a gripping outer shell 19 connected to one side of the main outer shell 18. A heat dissipation channel 10 is arranged along the interior of the main outer shell 18 and the gripping outer shell 19. The drive motor 3 is installed inside the main outer shell 18, resulting in high space utilization within the housing 1. The circuit board controller 5 is installed inside the gripping outer shell 19, and the first air inlet duct 111 is located at the rear of the gripping outer shell 19, while the second air inlet duct 112 is located at the front of the gripping outer shell 19. This design prevents the operator from accidentally touching the first air inlet duct 111 or the second air inlet duct 112 when gripping the gripping outer shell 19, thus avoiding airflow obstruction.

[0036] In this embodiment, the housing 1 includes a first half-shell 1a and a second half-shell 1b that are detachably connected to each other. The main housing 18 and the gripping housing 19 are respectively formed by the first half-shell 1a and the second half-shell 1b. The first air inlet duct 111 and the second air inlet duct 112 are respectively arranged on the lower side of the circuit board controller 5. The first air inlet duct 111 is provided on the first half-shell 1a and the second half-shell 1b, and the second air inlet duct 112 is provided on the first half-shell 1a and the second half-shell 1b, so that air can be drawn in from the two first air inlet ducts 111 and the two second air inlet ducts 112 respectively, thereby increasing the air intake volume. In other embodiments, the first air inlet duct 111 may be provided only on either the first half-shell 1a or the second half-shell 1b, or the second air inlet duct 112 may be provided only on either the first half-shell 1a or the second half-shell 1b, or the first air inlet duct 111 may be provided on both the first half-shell 1a and the second half-shell 1b, or the second air inlet duct 112 may be provided on both the first half-shell 1a and the second half-shell 1b.

[0037] like Figure 4 As shown, in this embodiment, the drive motor 3 is arranged longitudinally, including a motor body 31 installed longitudinally within the heat dissipation channel 10, and a drive shaft 32 rotatably connected within the motor body 31. The upper end of the drive shaft 32 protrudes from the upper end of the motor body 31 and is rotatably connected to the main housing 18 via a first bearing 33 installed within the heat dissipation channel 10, thereby improving the rotational stability of the drive shaft 32. The cooling fan 4, during operation, blows air from the first air inlet duct 111 and the second air inlet duct 112 towards the motor body 31 and the first bearing 33, dissipating heat from both the motor body 31 and the first bearing 33, preventing the high-speed rotating first bearing 33 from overheating and being damaged, thus affecting the normal operation of the drive motor 3. Furthermore, the cooling fan 4 is arranged transversely, while the drive motor 3 is arranged longitudinally, thus effectively blowing air onto the sides of the drive motor 3, improving the heat dissipation efficiency of the sides of the drive motor 3.

[0038] In this embodiment, the drive shaft 32 is arranged along the first longitudinal axis L1, and the cooling fan 4 is arranged along the first transverse axis L2. The first transverse axis L2 and the first longitudinal axis L1 are located on the same longitudinal plane and are arranged at an angle to each other, and the angle is less than 90°. This allows the fan direction of the cooling fan 4 to take into account both the motor body 31 and the first bearing 33, and the suction direction of the cooling fan 4 to take into account both the intake direction of the first air intake duct 111 and the second air intake duct 112. Optionally, the angle is less than 90° and greater than 70°, especially when it is 80° or near the angle, the effect of taking into account both is the best.

[0039] In this embodiment, a baffle plate 13 is provided on the inner wall of the housing 1, which is arranged on the upper side of the drive motor 3 and the side away from the cooling fan 4. The baffle plate 13 forms part of the side wall structure of the heat dissipation channel 10. By blocking the wind from spreading upward or away from the cooling fan 4, the wind can bounce downward and towards the cooling fan 4 after blowing towards the baffle plate 13. This forces the wind to blow downward along the axial direction of the heat dissipation channel 10 to the inside and outer periphery of the motor body 31 for heat dissipation, and blow towards the side of the motor body 31 away from the cooling fan 4 for heat dissipation. This provides all-round airflow heat dissipation to the inside and outer periphery of the motor body 31, improves the airflow guidance of the heat dissipation channel 10, and improves the heat dissipation effect on the motor body 31.

[0040] In this embodiment, a bearing mounting seat 131 is provided on a portion of the wind baffle 13 arranged on the upper side of the drive motor 3. The first bearing 33 is mounted on the bearing mounting seat 131, which can enhance the stability of the wind baffle 13 structure and make the first bearing 33 close to the wind baffle 13. This allows the first bearing 33 to be cooled by the wind blowing towards the wind baffle 13, and also by the wind rebounding from the wind baffle 13, thus improving the heat dissipation effect of the first bearing 33.

[0041] like Figure 2 As shown, in this embodiment, the housing 1 is provided with a switch 6 and a speed regulator 7, which are electrically connected to the circuit board controller 5, respectively. The switch 6 is used to start or stop the drive motor 3, and the speed regulator 7 is used to adjust the rotation speed of the drive shaft 32. The cooling fan 4 can be electrically connected to the circuit board controller 5, or it can be directly electrically connected to the power supply component so that the cooling fan 4 is started when the power tool is powered on. Alternatively, a separate control button can be provided on the housing 1 to start or adjust the cooling fan 4.

[0042] like Figure 4As shown, in this embodiment, a working component 2 is also arranged near the air outlet 12. The working component 2 includes an eccentric structure 22 that is driven by the drive shaft 32 of the drive motor 3, a polishing disk 21 that is rotatably connected to the lower side of the eccentric structure 22 off the axis of the drive shaft 32, and a fan blade structure 23 mounted on the eccentric structure 22. The air outlet 12 includes a first air outlet duct 121 arranged opposite to the back of the polishing disk 21. When the working component 2 is working, the fan blade structure 23 rotates with the eccentric structure 22 and blows the air drawn in from the upper side of the fan blade structure 23 along the heat dissipation channel 10 toward the back of the polishing disk 21 to clean and dissipate heat from the polishing disk 21. The polishing disk 21 and the first air outlet duct 121 are arranged with a gap for air to be blown out to the outside through the gap. In this embodiment, within the heat dissipation channel 10, the cooling fan 4 draws external air into the heat dissipation channel 10 through the air inlet 11 and blows it toward the motor body 31 and the first bearing 33. At the same time, the fan blade structure 23 draws air from the direction of the motor body 31 and the first bearing 33 into the heat dissipation channel 10 and blows it toward the polishing disc 21 and out through the gap between the polishing disc 21 and the first air outlet 121, forming a heat dissipation cycle.

[0043] like Figure 4 As shown, in this embodiment, the grip shell 19 and the main shell 18 are arranged at an angle. The second air inlet duct 112 is located at the angle connection between the grip shell 19 and the main shell 18, and has a first air inlet path S1 towards the inside of the grip shell 19 and a second air inlet path S2 towards the inside of the main shell 18. The heat dissipation channel 10 includes a third channel section 103 arranged between the second air inlet duct 112 and the fan blade structure 23. The second air inlet duct 112 is connected to the third channel section 103 along the second air inlet path S2, so that the warm air after heat exchange with the drive motor 3 and the cold air drawn in from the outside through the second air inlet path S2 are respectively fanned towards the back of the polishing disk 21 through the fan blade structure 23, and blown out to the outside through the gap between the polishing disk 21 and the first air outlet duct 121. Thus, while dissipating heat from the drive motor 3, the polishing disk 21 can also be purged and dissipated by the combined blowing of cold and warm air, realizing the overall heat dissipation of the circuit board controller 5, the drive motor 3, and the working component 2, and further improving the airflow utilization rate in the heat dissipation channel 10. The second air inlet duct 112 is designed with an opening diameter larger than that of the first air inlet duct 111, increasing the air intake volume of the second air inlet duct 112. This, in turn, increases the cooling efficiency of the cooling fan 4 blowing air towards the drive motor 3, making it more effective for blowing and cooling the drive motor 3. A filter frame is installed outside the second air inlet duct 112, and a filter screen is installed on the filter frame. The filter screen is used to prevent debris from being sucked into the housing 1 and affecting the normal operation of the drive motor 3. The air outlet 12 also includes a second air outlet duct 122 that is opened on the housing 1 near the eccentric structure 22, improving the efficiency of warm air exhaust from the housing 1 and preventing warm air from accumulating inside the housing 1 and failing to effectively dissipate to the outside.

[0044] In this embodiment, a motor mounting base 14 protrudes from the inner wall of the housing 1 and is arranged around the motor body 31. The motor body 31 is mounted on the motor mounting base 14, and after installation, a spaced channel 104 is formed between the motor body 31 and the housing 1 to allow air to be blown towards the working component 2. A motor fixing sleeve 15 is installed longitudinally on the inner wall of the housing 1. The lower part of the drive shaft 32 protrudes from the lower end of the motor body 31 and is axially supported within the motor fixing sleeve 15 by a second bearing 34. Thus, the drive shaft 32 is stably supported by the first bearing 33 and the second bearing 34, further improving the rotational stability of the drive shaft 32. The motor fixing sleeve 15 is provided with an air passage 105 to allow air to be blown towards the working component 2. The working component 2 is arranged on the lower side of the motor fixing sleeve 15. The spaced channel 104 and the air passage 105 are respectively set as part of the structure of the heat dissipation channel 10, ensuring that the air flowing through the motor body 31 can flow along the heat dissipation channel 10 towards the working component 2 to continue to dissipate heat from the working component 2 or be discharged to the outside from the air outlet 12.

[0045] like Figure 5 As shown, in this embodiment, the eccentric structure 22 includes an eccentric block 221 that is connected to the lower end of the drive shaft 32, and a counterweight block 222 arranged around the eccentric block 221 and connected to it. The counterweight block 222 is used to ensure the balance of the eccentric structure 22 and ensure that the eccentric structure 22 can rotate smoothly. The fan blade structure 23 includes a fan blade portion 231 sleeved on the outer periphery of the eccentric block 221, an upper fastening portion 232 fastened to the upper side of the eccentric block 221 and connected to the fan blade portion 231, a lower fastening portion 233 fastened to the lower side of the eccentric block 221 and connected to the fan blade portion 231, and a counterweight channel 234 corresponding to the counterweight block 222 that passes through the circumference of the fan blade portion 231. The fan blade portion 231 is axially fastened through the upper fastening portion 232 and the lower fastening portion 233. Connected to the eccentric block 221, the counterweight block 222 is positioned within the counterweight channel 234, further axially limiting the fan blade 231 to the upper and lower sides of the counterweight block 222, and circumferentially limiting the fan blade 231 to the left and right sides of the counterweight block 222. This ensures that the fan blade structure 23 is stably connected to the eccentric structure 22, preventing axial or circumferential movement relative to the eccentric structure 22, thus facilitating synchronous rotation between the fan blade structure 23 and the eccentric structure 22. The fan blade 231 has several fan blades 2311 for fanning, allowing the fan blades 2311 to direct the airflow from the upper side of the fan blade structure 23 towards the back of the polishing disc 21 when the fan blade structure 23 rotates.

[0046] In summary, the above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall fall within the scope of the patent of the present utility model.

Claims

1. A multi-channel heat dissipation device, characterized in that, include: The housing has a heat dissipation channel inside, and the housing is provided with an air inlet and an air outlet that are respectively connected to the heat dissipation channel. The air inlet includes a first air inlet channel and a second air inlet channel arranged between the first air inlet channel and the air outlet. A circuit board controller, a drive motor, and a cooling fan are respectively installed in the heat dissipation channel. The circuit board controller is arranged between the first air inlet channel and the second air inlet channel; the drive motor is arranged between the second air inlet channel and the air outlet and is electrically connected to the circuit board controller; the cooling fan is arranged between the second air inlet channel and the drive motor. When the cooling fan is working, it blows the air drawn in from the first air inlet channel and the second air inlet channel along the heat dissipation channel toward the drive motor. The air drawn in from the first air inlet channel can exchange heat with the circuit board controller as it moves toward the cooling fan.

2. The multi-channel heat dissipation device according to claim 1, characterized in that: The inner wall of the housing is provided with a controller mounting base. The circuit board controller is mounted on the controller mounting base. After installation, a moving channel is formed between the circuit board controller and the housing for the air drawn in from the first air inlet to move toward the cooling fan. The moving channel is set as part of the heat dissipation channel structure.

3. The multi-channel heat dissipation device according to claim 2, characterized in that: The circuit board controller has moving channels between its upper side and the housing, and between its lower side and the housing, for air drawn in from the first air inlet to move toward the cooling fan.

4. The multi-channel heat dissipation device according to claim 3, characterized in that: The heat dissipation channel includes a first channel section arranged on the side of the circuit board controller away from the cooling fan and a second channel section arranged on the side of the circuit board controller closer to the cooling fan. The first air inlet and the movable air ducts arranged on the upper and lower sides of the circuit board controller are respectively connected to the first channel section, and the second air inlet is connected to the second channel section.

5. The multi-channel heat dissipation device according to any one of claims 1-4, characterized in that: The housing includes a main shell and a grip shell connected to one side of the main shell. The heat dissipation channel is arranged along the interior of the main shell and the grip shell. The drive motor is installed inside the main shell. The circuit board controller is installed inside the grip shell. The first air inlet is located at the rear of the grip shell, and the second air inlet is located at the front of the grip shell.

6. The multi-channel heat dissipation device according to claim 5, characterized in that: The housing includes a first half-shell and a second half-shell that are detachably connected to each other. The main body shell and the grip shell are respectively formed by the first half-shell and the second half-shell. The first air inlet and the second air inlet are respectively arranged on the lower side of the circuit board controller. The first air inlet is arranged on the first half-shell and / or the second half-shell, and the second air inlet is arranged on the first half-shell and / or the second half-shell. The cooling fan is arranged at an upward angle so that it can blow the air drawn in from the first air inlet and the second air inlet towards the drive motor and its upper side when it is working.

7. The multi-channel heat dissipation device according to claim 6, characterized in that: The drive motor is arranged longitudinally and includes a motor body installed longitudinally in a heat dissipation channel and a drive shaft rotatably connected in the motor body. The upper end of the drive shaft protrudes from the upper end of the motor body and is rotatably connected to the main body shell through a first bearing installed in the heat dissipation channel. The cooling fan can blow air from the first air inlet and the second air inlet towards the motor body and the first bearing when working.

8. The multi-channel heat dissipation device according to claim 5, characterized in that: It also includes a working component arranged near the air outlet. The working component includes an eccentric structure that is driven by the drive shaft of the drive motor, a polishing disk that is rotatably connected to the lower side of the eccentric structure off the axis of the drive shaft, and a fan blade structure mounted on the eccentric structure. The air outlet includes a first air outlet duct arranged opposite to the back of the polishing disk. When the working component is working, the fan blade structure rotates with the eccentric structure and fans the air drawn in from the upper side of the fan blade structure to blow it along the heat dissipation channel toward the back of the polishing disk.

9. The multi-channel heat dissipation device according to claim 8, characterized in that: The grip shell and the main shell are arranged at an angle. The second air inlet is located at the angle connection between the grip shell and the main shell, and has a first air inlet path toward the grip shell and a second air inlet path toward the main shell. The heat dissipation channel includes a third channel section arranged between the second air inlet and the fan blade structure, and the second air inlet is connected to the third channel section along the second air inlet path.

10. A power tool, characterized in that: Includes the multi-channel heat dissipation device as described in any one of claims 1-9.

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