Alternating current polishing machine

Abstract

The invention discloses an alternating current polishing machine. The alternating current polishing machine comprises an output shaft, a brushless motor, a transmission mechanism, a machine shell, a control assembly and an anti-electromagnetic interference device, the output shaft is used for driving a working accessory to move, the brushless motor is provided with or connected with a motor shaft, the transmission mechanism is used for achieving transmission between the motor shaft and the output shaft, and the machine shell forms a holding part for a user to hold. The control assembly comprises a circuit board assembly and a circuit element, and the anti-electromagnetic interference device is used for suppressing electromagnetic interference. The nominal power of the whole brushless motor is greater than 500W and less than 2500W; the distance between the tail of the machine shell and the center line of the output shaft is the first length L3, and the first length L3 is smaller than or equal to 450 mm. According to the alternating current polishing machine, due to the arrangement, the size of the brushless motor is not too large, the overall length of the machine shell is short, and miniaturization can be achieved easily.

Description

Technical Field

[0001] The present application relates to an electric tool, in particular to an AC polishing machine. Background Art

[0002] A polishing machine, as used in related art, is a grinding tool that uses a motor to drive a polishing disc to rotate at high speed, causing the disc to polish the surface of a workpiece. Also known as a grinder, a polishing machine is commonly used for mechanical grinding, polishing, and waxing. The polishing disc, which can be a sponge or wool polishing disc, rubs the surface to be polished with the polishing compound, thereby removing paint contamination, oxide layers, and shallow scratches.

[0003] The polishing machine requires a motor to provide power. Existing polishing machines are becoming larger and larger due to the pursuit of high motor power, which makes it difficult for users to hold the polishing machine and operate it.

[0004] This section provides background information related to the present application which is not necessarily prior art. Summary of the Invention

[0005] One object of the present application is to solve or at least alleviate part or all of the above problems. To this end, one object of the present application is to provide an AC polishing machine with a smaller size, so that the AC polishing machine is miniaturized.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] An AC polishing machine includes: an output shaft for driving a working accessory to move; a brushless motor provided with or connected to a motor shaft; a transmission mechanism for realizing transmission between the motor shaft and the output shaft; a housing forming a grip for a user to hold; a control assembly including a circuit board assembly and circuit elements; an anti-electromagnetic interference device for suppressing electromagnetic interference; the nominal power of the brushless motor is greater than 500W and less than 2500W; the distance from the tail of the housing to the center line of the output shaft is a first length L3, and the first length L3 is less than or equal to 450mm.

[0008] In some embodiments, the circuit board assembly includes at least a first circuit board and a second circuit board, and when viewed from a direction perpendicular to the first circuit board, the first circuit board and the second circuit board at least partially overlap.

[0009] In some embodiments, the circuit board assembly includes at least a first circuit board and a second circuit board. When viewed in a direction perpendicular to the first circuit board, the first circuit board and the second circuit board at least partially overlap, the area of ​​the first circuit board is greater than or equal to the area of ​​the second circuit board, and the maximum length L of the control assembly along the extension direction of the control assembly is less than or equal to 75 mm.

[0010] In some embodiments, the working accessory is used to clamp the polishing disk, and the projection area of ​​the first circuit board on the polishing plane of the polishing disk is less than or equal to 3000 square millimeters; and / or, the projection area of ​​the second circuit board on the polishing plane of the polishing disk is less than or equal to 2500 square millimeters.

[0011] In some embodiments, the anti-electromagnetic interference device includes an anti-electromagnetic interference circuit board, and the anti-electromagnetic interference circuit board is configured as a single-board structure.

[0012] In some embodiments, the maximum length of the anti-electromagnetic interference circuit board is less than 65 mm; or, the maximum length of the anti-electromagnetic interference circuit board is less than 55 mm; or, the maximum length of the anti-electromagnetic interference circuit board is less than 45 mm.

[0013] In some embodiments, the area of ​​the anti-electromagnetic interference circuit board is less than or equal to 1500 planar millimeters.

[0014] In some embodiments, the AC polishing machine further includes a fan, which is sleeved on the motor shaft and located between the brushless motor and the control component.

[0015] In some embodiments, the housing is formed with a first air outlet located in front of the brushless motor, a second air outlet located at the control component, and a third air outlet located at the rear end of the grip portion. Under the action of the fan, a heat dissipation airflow is formed flowing in from the first air outlet and flowing out from the second air outlet and the third air outlet.

[0016] In some embodiments, the housing is formed with a first air outlet located in front of the brushless motor, a second air outlet located at the control component, a third air outlet located at the rear end of the grip portion, and at least one fourth air outlet radially opposite to the fan. Under the action of the fan, a heat dissipation airflow is formed flowing in from the first air outlet, the second air outlet, and the third air outlet and flowing out from the fourth air outlet.

[0017] In some embodiments, the brushless motor includes a first bearing supported at a front end of the motor shaft, and the first bearing at least partially overlaps with a stator of the brushless motor in an axial direction of the motor shaft.

[0018] In some embodiments, the brushless motor includes a second bearing supported at a rear end of the motor shaft, and the second bearing at least partially overlaps with the fan in an axial direction of the motor shaft.

[0019] In some embodiments, the control assembly includes a circuit board assembly, and a plane where the circuit board assembly is located is arranged at an angle to the axis of the motor shaft.

[0020] In some embodiments, the plane where the circuit board assembly is located is substantially perpendicular to the axis of the motor shaft.

[0021] In some embodiments, the circuit board assembly includes at least one circuit board, and the circuit board is a non-circular plate having a side wall formed by an arc surface and a flat surface.

[0022] In some embodiments, the circuit board assembly includes a plurality of circuit boards, and the plurality of circuit boards are all perpendicular to the axial direction of the motor shaft.

[0023] In some embodiments, the circumference D1 of the grip portion along the midline is less than 135 mm.

[0024] In some embodiments, a circumference D2 of the motor housing of the brushless motor at a mid-stator dividing line is less than or equal to 235 mm.

[0025] In some embodiments, the power of the brushless motor is greater than or equal to 1000W and less than or equal to 2000W.

[0026] In some embodiments, a stack length of the brushless motor is greater than or equal to 10 mm and less than or equal to 50 mm.

[0027] In some embodiments, the outer diameter of the brushless motor is greater than or equal to 30 mm and less than or equal to 65 mm.

[0028] The benefits of this application are:

[0029] The AC polishing machine provided in this application includes an output shaft, a brushless motor, a transmission mechanism, a housing, a control assembly, and an anti-electromagnetic interference device. The output shaft is used to drive the working accessory to move. The brushless motor is provided with or connected to a motor shaft. The transmission mechanism is used to achieve transmission between the motor shaft and the output shaft. The housing forms a grip for a user to hold. The control assembly includes a circuit board assembly and circuit elements. The anti-electromagnetic interference device is used to suppress electromagnetic interference. In addition, the nominal power of the brushless motor is greater than 500W and less than 2500W; the distance from the rear end of the housing to the centerline of the output shaft is a first length L3, and the first length L3 is less than or equal to 390mm. The AC polishing machine is configured in this manner so that the size of the brushless motor is not too large and the overall length of the housing is short, which is conducive to miniaturization. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of a power tool;

[0031] Figure 2 It is an exploded view of a power tool;

[0032] Figure 3 This is the main view of the power tool after removing the working accessories;

[0033] Figure 4 It is a schematic diagram of the brushless motor, transmission mechanism and output shaft from a certain perspective;

[0034] Figure 5 yes Figure 4 a schematic diagram of the structure shown at another viewing angle;

[0035] Figure 6 yes Figure 4 a cross-sectional view of the structure shown;

[0036] Figure 7 It is a cross-sectional view of a brushless motor;

[0037] Figure 8 This is an exploded diagram of the first type of control component;

[0038] Figure 9 It is a schematic diagram of the dimensions of the power tool;

[0039] Figure 10 This is a schematic diagram of the dimensions of the circuit board of the first control component;

[0040] Figure 11 is a layout diagram of circuit elements of the first control assembly;

[0041] Figure 12 is a schematic diagram of a partial structure of the first control component;

[0042] Figure 13 yes Figure 12 a schematic diagram of the structure shown at another viewing angle;

[0043] Figure 14 yes Figure 12 Schematic diagram of the structure shown with the control box removed;

[0044] Figure 15 It is a schematic diagram of the radiator of the first control assembly;

[0045] Figure 16 It is an exploded view of another power tool;

[0046] Figure 17 is a schematic diagram of the second control component;

[0047] Figure 18 yes Figure 17 Schematic diagram of the structure shown with the control box removed;

[0048] Figure 19 yes Figure 18 Exploded view of the structure shown;

[0049] Figure 20 yes Figure 18 a cross-sectional view of the structure shown;

[0050] Figure 21 It is an exploded diagram of another power tool;

[0051] Figure 22 is a schematic diagram of the third control component;

[0052] Figure 23 yes Figure 22 Exploded view of the structure shown;

[0053] Figure 24 yes Figure 23 a schematic diagram of the structure shown at another viewing angle;

[0054] Figure 25 is a layout diagram of circuit elements of a third control assembly;

[0055] Figure 26 This is a schematic diagram of heat dissipation holes provided on a circuit board of a third control component;

[0056] Figure 27 It is a schematic diagram of an anti-electromagnetic interference device;

[0057] Figure 28 This is a schematic diagram of the location of the motor switch;

[0058] Figure 29 This is a diagram of the vents on a power tool;

[0059] Figure 30 This is a schematic diagram of the first flow path of the heat dissipation airflow of the power tool;

[0060] Figure 31 This is a schematic diagram of the second flow path of the heat dissipation airflow of the power tool.

[0061] 10. Casing; 101. First housing; 102. Second housing; 103. Third housing; 104. First air outlet; 105. Second air outlet; 106. Third air outlet; 107. Fourth air outlet;

[0062] 11. Grip; 12. Output shaft; 13. Working accessories;

[0063] 14. Brushless motor; 141. Motor shaft; 142. Stator; 143. Rotor; 144. Motor housing; 145. First bearing; 146. Second bearing; 147. Bearing locator; 148. Noise reduction metal ring;

[0064] 15. Transmission mechanism; 151. Planetary gear assembly; 152. First bevel gear; 153. Second bevel gear; 154. First reduction shaft; 155. Second reduction shaft;

[0065] 16. Fan; 17. Power cord; 18. Motor switch;

[0066] 20. Control assembly; 21. Circuit board assembly; 201. Board surface; 202. Plane; 203. Curved surface; 204. Non-circular plate; 211. First circuit board; 2111. Heat dissipation holes; 212. Second circuit board; 22. Circuit element; 221. Electronic switch; 2211. First assembly port; 222. Rectifier; 2221. Second assembly port; 223. Second capacitor; 23. Radiator; 231. Third assembly port; 232. First heat dissipation portion ; 233, second heat dissipation portion; 234, first main body mounting plate; 235, heat dissipation rib; 2351, first air flow channel; 2352, second air flow channel; 2354, first heat dissipation rib; 2355, second heat dissipation rib; 236, second main body mounting plate; 237, third heat dissipation rib; 2301, first radiator; 2302, second radiator; 2303, third radiator; 2304, fourth radiator; 24, control box; 25, colloid;

[0067] 30. Anti-electromagnetic interference device; 31. Anti-electromagnetic interference circuit board; 32. First capacitor; 33. Resistor; 34. Inductor; 35. AC socket; 36. Mounting box;

[0068] 40. Speed ​​regulator. DETAILED DESCRIPTION

[0069] Before any embodiments of the present application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the foregoing drawings.

[0070] In this application, the terms "comprises," "includes," "has," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0071] In this application, the term "and / or" describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Additionally, the character " / " in this application generally indicates that the related objects are in an "and / or" relationship.

[0072] In this application, the terms "connect," "combine," "couple," and "install" may refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without an intermediary, and an indirect connection refers to two parts or components being connected to at least one intermediary, with the two parts or components being connected via the intermediary. Furthermore, "connect" and "couple" are not limited to physical or mechanical connections or couplings and may include electrical connections or couplings.

[0073] In this application, it will be understood by those skilled in the art that relative terms (e.g., "about," "approximately," "substantially," etc.) used in conjunction with quantities or conditions include the values ​​and have the meaning indicated by the context. For example, the relative terms include at least the degree of error associated with the measurement of a specific value, the tolerance caused by manufacturing, assembly, use, etc. associated with a specific value. Such terms should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to plus or minus a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. In addition, "substantially" may refer to plus or minus a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) on the basis of the indicated angle when expressing a relative angular position relationship (e.g., substantially parallel, substantially perpendicular).

[0074] In this application, it will be understood by those skilled in the art that the function performed by an assembly can be performed by one assembly, multiple assemblies, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one assembly, or a combination of multiple parts.

[0075] In the present application, the terms "upper", "lower", "left", "right", "front", "back" and other directional words are described based on the orientation and positional relationship shown in the accompanying drawings, and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to the other element "upper" or "lower", but also be indirectly connected to the other element "upper" or "lower" through an intermediate element. It should also be understood that directional words such as upper side, lower side, left side, right side, front side, back side, etc. not only represent the positive orientation, but can also be understood as the lateral orientation. For example, below can include directly below, lower left, lower right, lower front and lower back, etc.

[0076] In this application, the terms "controller," "processor," "central processing unit," "CPU," and "MCU" are used interchangeably. Where a unit "controller," "processor," "central processing unit," "CPU," or "MCU" is used to perform a particular function, unless otherwise specified, the function may be performed by a single unit or multiple units.

[0077] In this application, the terms "device", "module" or "unit" can be implemented in the form of hardware or software to achieve specific functions.

[0078] In this application, the terms "calculate", "judge", "control", "determine", "identify", etc. refer to the operations and processes of a computer system or similar electronic computing device (e.g., controller, processor, etc.).

[0079] The present application provides an electric tool. In some embodiments, the electric tool may be an AC polisher. Of course, in other embodiments, the electric tool can be replaced with operating accessories as needed to enable the electric tool to be used to perform other operations, such as an impact drill, an electric screwdriver, etc.

[0080] like Figures 1 to 6 As shown, the electric tool includes a housing 10 , a brushless motor 14 , a transmission mechanism 15 , an output shaft 12 , a working accessory 13 , a fan 16 , a control component 20 , an anti-electromagnetic interference device 30 and a speed regulator 40 .

[0081] The housing 10 is the main installation component and protective component of the power tool. The housing 10 can be an integrally formed part or formed by connecting multiple parts. Figure 2As shown, the housing 10 includes a first housing 101, a second housing 102, and a third housing 103. The first housing 101 and the second housing 102 are each half-shells. The first housing 101 and the second housing 102 are joined together to form the rear housing of the housing 10. The control assembly 20, the anti-electromagnetic interference device 30, and the speed regulator 40 are all mounted within the rear housing. A through-hole is formed at the rear of the rear housing for the power cord 17 to extend into. The third housing 103 is the front housing of the power tool. The third housing 103 can be formed by joining two half-shells or as an integrally formed part. The transmission mechanism 15 and the top of the output shaft 12 are placed within the third housing 103. A through-hole is formed at the bottom of the third housing 103 for the output shaft 12 to extend into.

[0082] The housing 10 partially forms a grip 11 for a user to grasp to operate the power tool. In some embodiments, the rear housing portion serves as the grip 11. An anti-slip structure is provided on the grip 11 to enhance the user's grip stability. The anti-slip structure may be a non-slip rubber sleeve, anti-slip texture, or the like.

[0083] In some embodiments, as Figure 3 As shown, the circumference D1 of the grip portion 11 along the midline is less than 135 mm. In one embodiment, the circumference D1 of the grip portion 11 along the midline is 133 mm; in one embodiment, the circumference D1 of the grip portion 11 along the midline is 130 mm; in one embodiment, the circumference D1 of the grip portion 11 along the midline is 127 mm; in one embodiment, the circumference D1 of the grip portion 11 along the midline is 122 mm; in one embodiment, the circumference D1 of the grip portion 11 along the midline is 119 mm; in one embodiment, the circumference D1 of the grip portion 11 along the midline is 115 mm.

[0084] The brushless motor 14 is placed in the housing 10. Specifically, the brushless motor 14 can be placed in the front housing or the rear housing. In some parallel embodiments, the motor housing 144 of the brushless motor 14 is externally mounted as part of the housing 10, and the motor housing 144 is connected between the front housing and the rear housing.

[0085] In addition to a motor housing 144, the brushless motor 14 also includes a stator 142, a rotor 143, and a bearing assembly disposed within the motor housing 144. In some embodiments, the bearing assembly of the brushless motor 14 includes a first bearing 145 supported at the front end of the motor shaft 141. The first bearing 145 and the stator 142 of the brushless motor 14 at least partially overlap along the axis of the motor shaft 141. This arrangement improves the compactness of the power tool's interior and facilitates miniaturization.

[0086] In one specific embodiment, the present application moves the bearing locating structure that secures the first bearing 145 15 mm inward of the motor housing 144 to the inside of the stator 142. In other embodiments, the distance of this movement can be adjusted as needed. The bearing locating structure can be a bearing seat or a locating groove.

[0087] Continue to refer to Figure 5 and Figure 6 As shown, the fan 16 is sleeved on the motor shaft 141 and is located between the brushless motor 14 and the control assembly 20. In some embodiments, the fan 16 is sleeved on the rear end of the motor shaft 141 of the brushless motor 14. The bearing assembly of the brushless motor 14 further includes a second bearing 146 supported on the rear end of the motor shaft 141. The second bearing 146 and the fan 16 at least partially overlap in the axial direction of the motor shaft 141.

[0088] In one specific embodiment, the present application moves the bearing locator 147 that secures the second bearing 146 14.5 mm inward of the motor housing 144 to the inner recess of the fan 16. In other embodiments, the distance of this movement can be adjusted as needed. The bearing locator 147 can be a bearing seat or a locating groove.

[0089] like Figure 7 As shown, in some embodiments, a noise reduction metal ring 148 is further provided on the outside of the stator 142. The noise reduction metal ring 148 is closely attached to the outer wall of the stator 142, thereby reducing the vibration of the stator 142 while achieving a noise reduction effect. In one embodiment, multiple noise reduction metal rings 148 are provided, and the multiple noise reduction metal rings 148 are spaced apart in the direction of the motor shaft 141 of the brushless motor 14.

[0090] In some embodiments, the power of the brushless motor 14 is greater than or equal to 1000 W and less than or equal to 2000 W. In the embodiment of the present application, the rated power of the brushless motor 14 is 1400 W.

[0091] In some embodiments, the stack length of the brushless motor 14 is greater than or equal to 10 mm and less than or equal to 50 mm. In one embodiment, the stack length of the brushless motor 14 is 15 mm; in one embodiment, the stack length of the brushless motor 14 is 25 mm; in one embodiment, the stack length of the brushless motor 14 is 35 mm; in one embodiment, the stack length of the brushless motor 14 is 35 mm; and in one embodiment, the stack length of the brushless motor 14 is 45 mm.

[0092] In some embodiments, the outer diameter of the brushless motor 14 is greater than or equal to 30 mm and less than or equal to 65 mm. In one embodiment, the outer diameter of the brushless motor 14 is 35 mm; in one embodiment, the outer diameter of the brushless motor 14 is 40 mm; in one embodiment, the outer diameter of the brushless motor 14 is 50 mm; and in one embodiment, the outer diameter of the brushless motor 14 is 60 mm.

[0093] Continue to refer to Figure 3 As shown, in some embodiments, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is less than or equal to 235 mm. In one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 230 mm; in one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 225 mm; in one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 222 mm; in one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 219 mm; in one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 215 mm; in one embodiment, the circumference D2 of the motor housing 144 of the brushless motor 14 at the bisection line in the stator 142 is 210 mm.

[0094] In some embodiments, the nominal power of the entire brushless motor 14 is greater than 500W and less than 2500W. It should be noted that the nominal power is the entire power of the power tool, specifically the entire power of an AC polishing machine. For an AC polishing machine, the nominal power refers to the power value indicated on the machine nameplate, which is also the rated power value of the machine. In one embodiment, the nominal power of the entire brushless motor 14 is 800W; in one embodiment, the nominal power of the entire brushless motor 14 is 1100W; in one embodiment, the nominal power of the entire brushless motor 14 is 1300W; in one embodiment, the nominal power of the entire brushless motor 14 is 1600W; in one embodiment, the nominal power of the entire brushless motor 14 is 1800W.

[0095] In some parallel embodiments, the nominal power of the brushless motor 14 is greater than 1000W and less than 2000W.

[0096] In some parallel embodiments, the nominal power of the brushless motor 14 is greater than 1200W and less than 1500W.

[0097] Continue to refer to Figures 4 to 6As shown, the brushless motor 14 is provided with or connected to a motor shaft 141, and the transmission mechanism 15 is connected between the motor shaft 141 and the output shaft 12 and is used to realize transmission between the motor shaft 141 and the output shaft 12. Compared with the existing polishing machine using a series-excited brush motor, which is difficult to replace the brush carbon, the present application can effectively solve this problem by using a brushless motor 14.

[0098] When the power tool is in operation, the motor shaft 141 is substantially horizontally arranged, and the output shaft 12 is substantially vertically arranged. In order to achieve power transmission between the motor shaft 141 and the output shaft 12, as shown in FIG. Figure 6 As shown, the transmission mechanism 15 includes a planetary gear assembly 151, a first bevel gear 152, a second bevel gear 153, a first reduction shaft 154 and a second reduction shaft 155. The motor shaft 141 of the brushless motor 14 is coaxially connected to the first reduction shaft 154, the first reduction shaft 154 is connected to the sun gear of the planetary gear assembly 151, and the second reduction shaft 155 is connected to the planet carrier of the planetary gear assembly 151. The first bevel gear 152 is formed on or connected to the second reduction shaft 155, and the second bevel gear 153 is formed on or connected to the output shaft 12.

[0099] When the motor shaft 141 of the brushless motor 14 rotates, the power is transmitted to the output shaft 12 through the first reduction shaft 154, the planetary gear assembly 151, the second reduction shaft 155, the first bevel gear 152 and the second bevel gear 153 in sequence, so that the output shaft 12 can drive the working accessory 13 to rotate, and the working accessory 13 can clamp the polishing disk (not shown in the figure) to achieve grinding and polishing of the workpiece to be processed.

[0100] As for the polishing pad, it is arranged substantially horizontally, and the diameter of the polishing pad is greater than or equal to 180 mm and less than or equal to 230 mm. In one embodiment, the diameter of the polishing pad is 180 mm; in one embodiment, the diameter of the polishing pad is 190 mm; in one embodiment, the diameter of the polishing pad is 200 mm; in one embodiment, the diameter of the polishing pad is 210 mm; in one embodiment, the diameter of the polishing pad is 220 mm; in one embodiment, the diameter of the polishing pad is 230 mm.

[0101] The control component 20 is used to control the brushless motor 14 and supply power to the brushless motor 14. Figures 8 to 15 A first configuration of the control assembly 20 is shown; Figures 16 to 20 A second configuration of the control assembly 20 is shown; Figures 21 to 26 The third structure of the control assembly 20 is shown. The following describes the specific structure of the control assembly 20. It should be noted that some components of the three structures are common to the control assembly 20, but are only shown in the drawings of one structure.

[0102] Specifically, the control assembly 20 includes a circuit board assembly 21, a circuit element 22, and a control box 24. The circuit board assembly 21 and the circuit element 22 are both disposed within the control box 24, and the circuit element 22 is integrated onto the circuit board assembly 21. To secure the circuit board assembly 21 and the circuit element 22 within the control box 24, after the circuit element 22 is mounted on the circuit board assembly 21, the resulting assembly is placed within the control box 24, and a colloid 25 is injected into the control box 24 to secure the circuit board assembly 21 and the circuit element 22 within the control box 24. Furthermore, injecting the colloid 25 into the control box 24 can also provide a certain degree of waterproofing and dustproofing. It should be noted that after the colloid 25 is injected into the control box 24, a portion of the circuit element 22 is still exposed outside the colloid, and this portion requires dustproofing. Therefore, protection is required on the exposed metal of the circuit element 22, such as forming a sealing layer, to prevent failure in the presence of water and dust.

[0103] In some embodiments, the plane where the circuit board assembly 21 is located is arranged at an angle to the axis of the motor shaft 141. In one embodiment, the plane where the circuit board assembly 21 is located is substantially perpendicular to the axis of the motor shaft 141.

[0104] The circuit board assembly 21 includes at least one circuit board. In some embodiments, the circuit board is arranged perpendicular to the axis direction of the motor shaft 141. In some embodiments, as Figure 8 、 Figure 18 and Figure 23 As shown, the circuit board assembly 21 includes two circuit boards, which are a first circuit board 211 and a second circuit board 212 electrically connected to each other. The first circuit board 211 and the second circuit board 212 are arranged substantially in parallel. When viewed from a direction perpendicular to the first circuit board 211, the first circuit board 211 and the second circuit board 212 at least partially overlap. The area of ​​the first circuit board 211 is greater than or equal to the area of ​​the second circuit board 212, and as shown in FIG. Figure 9 As shown, the maximum length L of the control assembly 20 along the extension direction of the grip portion 11 is less than or equal to 75 mm. By providing two circuit boards, different types of circuit components 22 can be electrically connected to different circuit boards. This configuration reduces the space occupied by the control assembly 20 and facilitates the miniaturization of the power tool.

[0105] In some embodiments, as Figure 10As shown, the maximum length L1 of the first circuit board 211 is less than or equal to 75 mm. In one specific embodiment, the maximum length L1 of the first circuit board 211 is 72 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 70 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 67 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 65 mm; and in one specific embodiment, the maximum length L1 of the first circuit board 211 is 60 mm.

[0106] In some embodiments, continue to refer to Figure 10 As shown, the maximum length L2 of the second circuit board 212 is less than or equal to 60 mm. In one specific embodiment, the maximum length L2 of the second circuit board 212 is 58 mm; in one specific embodiment, the maximum length L2 of the second circuit board 212 is 55 mm; in one specific embodiment, the maximum length L2 of the second circuit board 212 is 53 mm; in one specific embodiment, the maximum length L2 of the second circuit board 212 is 51 mm; and in one specific embodiment, the maximum length L2 of the second circuit board 212 is 48 mm.

[0107] In one embodiment, the length of the first circuit board 211 is 72 mm, and the width W of the first circuit board 211 is 39 mm; the length of the second circuit board 212 is 60 mm, and the width W of the second circuit board 212 is 39 mm.

[0108] In some embodiments, along the extension direction of the grip portion 11, the maximum length of the first circuit board 211 is less than or equal to 75 mm. In some embodiments, along the extension direction of the grip portion 11, the maximum length L2 of the second circuit board 212 is less than or equal to 60 mm. It should be noted that along the extension direction of the grip portion 11, the maximum length of the first circuit board 211 is related to the position of the first circuit board 211 in the grip portion 11. When the first circuit board 211 is parallel to the extension direction of the grip portion 11, the maximum length of the first circuit board 211 along the extension direction of the grip portion 11 is the above-mentioned L1. When the first circuit board 211 is tilted relative to the extension direction of the grip portion 11, the maximum length of the first circuit board 211 along the extension direction of the grip portion 11 is equal to the length of the projection of the first circuit board 211 in the extension direction of the grip portion 11. This length is less than L1; similarly, the maximum length of the second circuit board 212 is related to the position of the second circuit board 212 in the holding portion 11. When the second circuit board 212 is parallel to the extension direction of the holding portion 11, the maximum length of the second circuit board 212 along the extension direction of the holding portion 11 is the above-mentioned L2. When the second circuit board 212 is tilted relative to the extension direction of the holding portion 11, the maximum length of the second circuit board 212 along the extension direction of the holding portion 11 is equal to the length of the projection of the second circuit board 212 in the extension direction of the holding portion 11, which is less than L2.

[0109] In some embodiments, the area of ​​the first circuit board 211 is less than or equal to 3000 square millimeters. In a specific embodiment, the area of ​​the first circuit board 211 is 2900 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2800 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2700 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2600 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2500 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2400 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2300 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2200 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2100 square millimeters; in a specific embodiment, the area of ​​the first circuit board 211 is 2000 square millimeters.

[0110] In some embodiments, the area of ​​the second circuit board 212 is less than or equal to 2500 square millimeters. In a specific embodiment, the area of ​​the second circuit board 212 is 2400 square millimeters; in a specific embodiment, the area of ​​the second circuit board 212 is 2300 square millimeters; in a specific embodiment, the area of ​​the second circuit board 212 is 2200 square millimeters; and in a specific embodiment, the area of ​​the second circuit board 212 is 2100 square millimeters.

[0111] In some embodiments, the projected area of ​​the first circuit board 211 on the polishing plane 202 of the polishing plate is less than or equal to 3000 square millimeters.

[0112] In some embodiments, the projected area of ​​the second circuit board 212 on the polishing plane 202 of the polishing plate is less than or equal to 2500 square millimeters.

[0113] In some embodiments, the ratio of the area of ​​the overlapping portion of the first circuit board 211 and the second circuit board 212 to the area of ​​the first circuit board 211 in a direction perpendicular to the first circuit board 211 is the overlap ratio, where the overlap ratio is greater than or equal to 50%. In one specific embodiment, the overlap ratio of the first circuit board 211 and the second circuit board 212 is 49%; in one specific embodiment, the overlap ratio of the first circuit board 211 and the second circuit board 212 is 48%; in one specific embodiment, the overlap ratio of the first circuit board 211 and the second circuit board 212 is 47%; in one specific embodiment, the overlap ratio of the first circuit board 211 and the second circuit board 212 is 46%; and in one specific embodiment, the overlap ratio of the first circuit board 211 and the second circuit board 212 is 45%.

[0114] Furthermore, the number of circuit boards included in the circuit board assembly 21 is not limited to two and can be set to three, four, or more as needed. In some embodiments, the circuit board assembly 21 also includes a third circuit board (not shown). When viewed perpendicular to the first circuit board 211, the first circuit board 211, the second circuit board 212, and the third circuit board at least partially overlap, and the area of ​​the first circuit board 211 is greater than or equal to the area of ​​the third circuit board. This arrangement can further reduce the size of the first circuit board 211 and the second circuit board 212, further facilitating the miniaturization of the power tool.

[0115] When the circuit board assembly 21 includes three circuit boards, the maximum length L1 of the first circuit board 211 can be effectively reduced, such that the maximum length L1 of the first circuit board 211 is less than or equal to 65 mm. In one specific embodiment, the maximum length L1 of the first circuit board 211 is 64 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 63 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 62 mm; in one specific embodiment, the maximum length L1 of the first circuit board 211 is 61 mm; and in one specific embodiment, the maximum length L1 of the first circuit board 211 is 60 mm.

[0116] In one embodiment, the length of the first circuit board 211 is 61.5 mm, and the width of the first circuit board 211 is 44 mm; the length of the second circuit board 212 is 50 mm, and the width of the second circuit board 212 is 36 mm; the length of the third circuit board is 63 mm, and the width of the third circuit board is 20 mm.

[0117] It should be noted that, in order to improve the structural compactness of the control component 20, the multiple circuit boards are basically arranged in parallel, and the control component 20 is arranged in the housing 10. In some embodiments, such as Figures 8 to 20 As shown, when the power tool is in working state, the circuit board is basically arranged horizontally and parallel to the central axis of the grip portion 11; in some parallel embodiments, when the power tool is in working state, such as Figures 21 to 26 As shown, the circuit board is basically vertically arranged and perpendicular to the central axis of the grip portion 11; of course, in other embodiments, when the power tool is in working state, the circuit board can also be tilted and arranged at an acute angle or an obtuse angle to the central axis of the grip portion 11.

[0118] Continue to refer to Figure 8 As shown, the circuit element 22 includes multiple electronic switches 221, a rectifier 222, a second capacitor 223 and a control module. In some embodiments, the multiple electronic switches 221, the rectifier 222 and the second capacitor 223 are all fixed on the circuit board. It should be noted that different types of circuit elements 22 can be fixed on the same circuit board or on different circuit boards. In one embodiment, the multiple electronic switches 221, the rectifier 222 and the second capacitor 223 are all fixed on the first circuit board 211, and the control module is set on the second circuit board 212.

[0119] Multiple electronic switches 221 are used to drive the brushless motor 14. Specifically, the multiple electronic switches 221 form a three-phase bridge circuit, and the rectifier 222 forms a DC unit. It receives AC power input from the power line 17 and outputs a DC bus voltage. In other words, it converts the AC power input through the power line 17 into pulsating DC power output. The control module is used to control the conduction state of the multiple electronic switches 221, thereby driving the normal operation of the brushless motor 14. In some embodiments, the control module is implemented using a control chip.

[0120] In some embodiments, the electronic switch 221 is perpendicular to the circuit board. In some embodiments, the electronic switch 221 is an IGBT, which stands for field-effect transistor; in some embodiments, the electronic switch 221 is a MOS; in some embodiments, the electronic switch 221 is a FET, which stands for field-effect transistor.

[0121] In some embodiments, the plurality of electronic switches 221 are regularly arranged on the first circuit board 211, for example, in rows and columns or in a ring. Figure 11 As shown, the first circuit board 211 is arranged above the second circuit board 212, and there are six electronic switches 221. The six electronic switches 221 are respectively distinguished by 221a, 221b, 221c, 221d, 221e, and 221f. The six electronic switches 221 are arranged in two rows and three columns. The rectifier 222 and the multiple electronic switches 221 are arranged side by side in the length direction of the first circuit board 211. There are three second capacitors 223, one of which is arranged on one side of the electronic switch 221, and the other two second capacitors 223 are arranged on both sides of the rectifier 222. Figure 11 As shown, the three second capacitors 223 are respectively distinguished by 223 a , 223 b , and 223 c .

[0122] In some parallel embodiments, Figures 17 to 19 As shown, the first circuit board 211 is arranged below the second circuit board 212, the number and arrangement of the electronic switches 221 and the rectifiers 222 remain unchanged, the number of the second capacitors 223 is adjusted to six, and they are arranged on the second circuit board 212, and the six second capacitors 223 are arranged in a row.

[0123] In some parallel embodiments, Figures 21 to 25As shown, the number of electronic switches 221, rectifiers 222, and second capacitors 223 remains unchanged, but their arrangement is adjusted. The six electronic switches 221 are arranged in two rows and three columns, the three second capacitors 223 are disposed between the two rows of electronic switches 221, and the rectifier 222 is disposed below the three second capacitors 223. Of course, in other embodiments, the arrangement of the electronic switches 221, rectifiers 222, and second capacitors 223 can be flexibly adjusted based on needs and the internal space of the grip 11.

[0124] Continue to refer to Figure 8 、 Figure 18 and Figure 22 As shown, the electric tool further includes a radiator 23, which is used to dissipate heat for the control component 20. The number of the radiators 23 can be set to one or more according to needs.

[0125] In some embodiments, continue to refer to Figures 12 to 15 As shown, when the power tool is in operation, the circuit boards are arranged substantially horizontally. The power tool is provided with a heat sink 23, which is located below the first circuit board 211. The heat sink 23 contacts the surfaces of the plurality of electronic switches 221 and the rectifier 222. The first pins of the electronic switches 221 and the second pins of the rectifier 222 are soldered to the back side of the circuit board. The heat sink 23 can dissipate heat from the electronic switches 221 and the rectifier 222 to prevent malfunctions caused by overheating. Of course, in other embodiments, the positions of the first circuit board 211 and the second circuit board 212 can also be adjusted so that the first circuit board 211 is located above the second circuit board 212, and the heat sink 23 is located above the first circuit board 211.

[0126] Continue to refer to Figure 15 As shown, the above-mentioned heat sink 23 includes a first heat dissipation portion 232 and a second heat dissipation portion 233 vertically connected. The first heat dissipation portion 232 is basically horizontally arranged and is arranged above multiple electronic switches 221 and rectifiers 222. A plurality of air flow channels that are basically parallel to the first circuit board 211 are formed on the first heat dissipation portion 232. The second heat dissipation portion 233 is inserted between the two rows of electronic switches 221 and is in contact with the two rows of electronic switches 221 and the rectifier 222. Such an arrangement can improve the heat dissipation effect and heat dissipation efficiency.

[0127] Continue to refer to Figure 8 and Figure 15As shown, to achieve a fixed connection between the heat sink 23, the electronic switch 221, and the rectifier 222, a first assembly opening 2211 is provided on the electronic switch 221, a second assembly opening 2221 is provided on the rectifier 222, and a plurality of third assembly openings 231 are provided on the heat sink 23. The first assembly opening 2211 is connected to the third assembly openings 231 in a one-to-one correspondence, and the second assembly opening 2221 is connected to the third assembly openings 231 in a one-to-one correspondence. A first connector passes through the first and third assembly openings 2211, 231 to secure the electronic switch 221 to the heat sink 23. A second connector passes through the second and third assembly openings 2221, 231 to secure the rectifier 222 to the heat sink 23. Screws can be used for the first and second connectors.

[0128] In one embodiment, four third assembly openings 231 are provided on the second heat dissipation portion 233 of the radiator 23, a first assembly opening 2211 is provided on each electronic switch 221, and a second assembly opening 2221 is provided on the rectifier 222. The first connecting member passes through the first assembly opening 2211 of an electronic switch 221 located on one side of the second heat dissipation portion 233, a third assembly opening 231 on the radiator 23, and the first assembly opening 2211 of another electronic switch 221 located on the other side of the second heat dissipation portion 233 to assemble the radiator 23 and the two electronic switches 221, so that the six electronic switches 221 can be fixed to the radiator 23 using only three first connecting members, and the remaining third assembly opening 231 is for the second connecting member to pass through.

[0129] In some parallel embodiments, Figures 22 to 24 As shown, when the power tool is in working state, the circuit boards are basically arranged vertically, and two radiators 23 are provided. The two radiators 23 are respectively the first radiator 2301 and the second radiator 2302. The first radiator 2301 and the second radiator 2302 respectively dissipate heat for each row of electronic switches 221.

[0130] like Figure 23 and Figure 24As shown, in some embodiments, the first heat sink 2301 and the second heat sink 2302 have the same structure, and both the first heat sink 2301 and the second heat sink 2302 include a first main body mounting plate 234 and heat dissipation ribs 235. The heat dissipation ribs 235 include a plurality of first heat dissipation ribs 2354 and a plurality of second heat dissipation ribs 2355. The first main body mounting plate 234 is an arc-shaped plate, and the first heat dissipation ribs 2354 are protruding from the side of the first main body mounting plate 234 closer to the circuit element 22, or in other words, closer to the second capacitor 223. A first air flow channel 2351 is formed between two adjacent first heat dissipation ribs 2354, and a second air flow channel 2352 is formed between two adjacent second heat dissipation ribs 2355. It should be noted that when installing the first radiator 2301 and the second radiator 2302, the first radiator 2301 and the second radiator 2302 are arranged relative to each other, so that the two first main body mounting plates 234 protrude in opposite directions, which can improve the smoothness of the air flow and thus improve the heat dissipation effect.

[0131] The directions of the air flow channels on the two heat sinks 23 of the first heat sink 2301 and the second heat sink 2302 are tilted to the board surface 201 of the circuit board. The air flow channel here refers to the channel for the heat dissipation air flow formed between any two adjacent heat dissipation ribs 235, which can be called an air flow channel. For a heat sink 23, it can have the same direction of the air flow channel, or it can have multiple different directions of the air flow channel. The first air flow channel 2351 and the second air flow channel 2352 in this embodiment are two different directions of the air flow channel. The board surface 201 of the circuit board can be the board surface of the first circuit board 211, or it can be the board surface of the second circuit board 212. In this embodiment, since the first circuit board 211 is substantially parallel to the second circuit board 212, Figure 24 The board surface 201 of the second circuit board 212 is shown as an example.

[0132] The electric tool is configured such that the air passage of the radiator 23 and the board surface 201 of the circuit board are tilted, which not only helps to reduce the radial size of the electric tool, thereby making it easier for the user to hold and operate the electric tool, and helps to achieve miniaturization of the electric tool, but also has a better heat dissipation effect on the control component 20. Figure 24 As shown, the angle between the air passage of the radiator 23 and the board surface 201 of the circuit board is represented by a. Figure 24In the embodiment, since the first heat sink 2301 and the second heat sink 2302 have substantially the same structure, the air flow channel here is described as the air flow channel 2352 formed by the first heat dissipation rib 2354 of the second heat sink 2302. Therefore, in this embodiment, one side of the angle a refers to the air flow channel 2352, and the other side refers to the board surface 2112 of the circuit board 201. In some embodiments, the angle a between the air flow channel of the heat sink 23 and the board surface 201 of the circuit board is greater than 0° and less than or equal to 90°. In one embodiment, the angle a between the air flow channel of the heat sink 23 and the board surface 201 of the circuit board is 90°; in one embodiment, the angle a between the air flow channel of the heat sink 23 and the board surface 201 of the circuit board is 60°; and in one embodiment, the angle a between the air flow channel of the heat sink 23 and the board surface 201 of the circuit board is 30°.

[0133] In some parallel embodiments, the angle a formed between the air passage of the heat sink 23 and the board surface 201 of the circuit board is greater than 30° and less than or equal to 90°.

[0134] In some parallel embodiments, the angle a formed between the air passage of the heat sink 23 and the board surface 201 of the circuit board is greater than 50° and less than or equal to 90°.

[0135] Continue to refer to Figure 23 and Figure 24 As shown, in addition to the first heat sink 2301 and the second heat sink 2302, the control assembly 20 also includes a third heat sink 2303, which is used to dissipate heat from the rectifier 222. In some embodiments, the third heat sink 2303 includes a second main mounting plate 236 and a plurality of third heat dissipation ribs 237. The second main mounting plate 236 is a flat plate, and the second heat dissipation ribs 237 are protruding from the outside of the third main mounting plate 236. Air channels are formed between adjacent third heat dissipation ribs 237. It should be noted that after the second heat sink 2302 and the second heat sink 2303 are installed, the third heat sink 2303 is mounted to the underside of the second heat sink 2302 and the second heat sink 2302, with the third heat dissipation ribs 237 protruding downward. This improves the smoothness of airflow and thus the heat dissipation effect.

[0136] It should be noted that the air flow channel formed on the third radiator 2303 can be arranged parallel to or at an angle to the air flow channels of the first radiator 2301 and the second radiator 2302. Therefore, the range of the angle a described above also applies to the third radiator 2303.

[0137] like Figure 23 and Figure 24As shown, in order to achieve a fixed connection between the radiator 23 and the electronic switch 221, a first assembly port 2211 is provided on the electronic switch 221, and a plurality of third assembly ports 231 are respectively provided on the first radiator 2301 and the second radiator 2302. The first assembly port 2211 is connected to the third assembly port 231 in a one-to-one correspondence, and the first connecting member passes through the first assembly port 2211 and the third assembly port 231 to achieve the fixation of the electronic switch 221 and the radiator 23.

[0138] In order to achieve a fixed connection between the third radiator 2303 and the rectifier 222, a second assembly port 2221 is provided on the rectifier 222, and a third assembly port 231 is provided on the third radiator 2303. The second assembly port 2221 is connected to the third assembly port 231 in a one-to-one correspondence, and the second connecting member passes through the second assembly port 2221 and the third assembly port 231 to achieve the fixation of the rectifier 222 and the radiator 23.

[0139] In one embodiment, three third assembly openings 231 are respectively provided on the first heat sink 2301 and the second heat sink 2302 , one third assembly opening 231 is provided on the third heat sink 2303 , a first assembly opening 2211 is provided on each electronic switch 221 , and a second assembly opening 2221 is provided on the rectifier 222 .

[0140] Continue to refer to Figure 23 and Figure 24 As shown, the control component 20 also includes a fourth radiator 2304, and the fourth radiator 2304 is integrated on the control box 24, so that the control box 24 has both installation function and heat dissipation function. The first circuit board 211 and the second circuit board 212 are both arranged in the control box 24. The fourth radiator 2304 includes a plurality of fourth heat dissipation ribs formed on the circumference of the control box 24, and air flow channels are formed between adjacent fourth heat dissipation ribs. It should be noted that the above range of the angle a also applies to the fourth radiator 2304.

[0141] According to the different shapes of the control box 24 or the different shapes of the internal space of the gripping portion 11, the shape of the circuit board can be flexibly adjusted. The circuit board can be set as a rectangular plate, a circular plate, or other polygonal plates. Figure 24 As shown, the circuit board is a non-circular plate 204 whose side wall is formed by an arc surface 203 and a flat surface 202.

[0142] In one specific embodiment, a non-circular plate 204 is formed by cutting the circuit board three times in a radial direction perpendicular to the circular plate, wherein the cut surfaces are the aforementioned planes 202. The three planes 202 are located in three directions of the circuit board, for example, the top, left, and right sides, or the bottom, left, and right sides. Two of the three planes 202 are arranged parallel to each other and perpendicular to the remaining plane 202. Furthermore, the circuit board includes three curved surfaces 203, each of which is arranged between two adjacent planes 202.

[0143] In one specific embodiment, the diameter of the curved surface 203 of the non-circular plate 204 is 51 mm; the distance between the two parallel flat surfaces 202 is 45 mm; and the distance between the remaining flat surface 202 and the curved surface 203 on the opposite side thereof is 48.5 mm. In one specific embodiment, the diameter of the curved surface 203 of the non-circular plate 204 is 51 mm; the distance between the two parallel flat surfaces 202 is 45 mm; and the distance between the remaining flat surface 202 and the curved surface 203 on the opposite side thereof is 46.5 mm.

[0144] In a specific embodiment, Figure 26 As shown, the circuit board is provided with heat dissipation holes 2111. The arrangement of the heat dissipation holes 2111 allows the heat dissipation airflow to flow smoothly through the circuit board when the circuit board is arranged perpendicular to the extension direction of the grip portion 11, thereby ensuring heat dissipation. The shape and number of the heat dissipation holes 2111 can be flexibly set according to needs.

[0145] like Figure 27 As shown, the anti-electromagnetic interference device 30 is used to suppress electromagnetic interference. In some embodiments, the anti-electromagnetic interference device 30 and the control component 20 are separately provided. By separately providing the electromagnetic interference device 30 and the control component 20, the electromagnetic interference device 30 and the control component 20 can make full use of the space inside the power tool for layout, which is conducive to miniaturization of the power tool. In a specific embodiment, in the extension direction of the grip 11, the anti-electromagnetic interference device 30 is provided behind the control component 20. Of course, in some other embodiments, the anti-electromagnetic interference device 30 can also be integrated with the control component 20.

[0146] In some embodiments, the minimum distance between the anti-electromagnetic interference device 30 and the control assembly 20 is greater than or equal to 10 mm. In one embodiment, the minimum distance between the anti-electromagnetic interference device 30 and the control assembly 20 is 9 mm; in one embodiment, the minimum distance between the anti-electromagnetic interference device 30 and the control assembly 20 is 8 mm; in one embodiment, the minimum distance between the anti-electromagnetic interference device 30 and the control assembly 20 is 7 mm; and in one embodiment, the minimum distance between the anti-electromagnetic interference device 30 and the control assembly 20 is 6 mm.

[0147] Continue to refer to Figure 27 As shown, the anti-electromagnetic interference device 30 includes an anti-electromagnetic interference circuit board 31 , a first capacitor 32 , a resistor 33 and an inductor 34 . The first capacitor 32 , the resistor 33 and the inductor 34 are all integrated on the anti-electromagnetic interference circuit board 31 .

[0148] In some embodiments, the anti-electromagnetic interference circuit board 31 is configured as a single board. Of course, in other embodiments, the anti-electromagnetic interference circuit board 31 can also be configured as a multi-board structure as needed. In some embodiments, the anti-electromagnetic interference circuit board 31 is arranged parallel to the extension direction of the grip portion 11; in some parallel embodiments, the anti-electromagnetic interference circuit board 31 is arranged at an angle relative to the extension direction of the grip portion 11.

[0149] In some embodiments, the maximum length of the anti-electromagnetic interference circuit board 31 is less than 65 mm. In one embodiment, the maximum length of the anti-electromagnetic interference circuit board 31 is 60 mm; in one embodiment, the maximum length of the anti-electromagnetic interference circuit board 31 is 58 mm; in one embodiment, the maximum length of the anti-electromagnetic interference circuit board 31 is 55 mm; in one embodiment, the maximum length of the anti-electromagnetic interference circuit board 31 is 52 mm; and in one embodiment, the maximum length of the anti-electromagnetic interference circuit board 31 is 40 mm.

[0150] In some parallel embodiments, the maximum length of the anti-electromagnetic interference circuit board 31 is less than 55 mm.

[0151] In some parallel embodiments, the maximum length of the anti-electromagnetic interference circuit board 31 is less than 45 mm.

[0152] In some embodiments, the area of ​​the anti-electromagnetic interference circuit board 31 is less than or equal to 1500 square millimeters. In one embodiment, the area of ​​the anti-electromagnetic interference circuit board 31 is 1400 square millimeters; in one embodiment, the area of ​​the anti-electromagnetic interference circuit board 31 is 1300 square millimeters; in one embodiment, the area of ​​the anti-electromagnetic interference circuit board 31 is 1200 square millimeters; in one embodiment, the area of ​​the anti-electromagnetic interference circuit board 31 is 1100 square millimeters; and in one embodiment, the area of ​​the anti-electromagnetic interference circuit board 31 is 1000 square millimeters.

[0153] In some embodiments, the resistor 33 is a power NTC resistor, and the inductor 34 is a common-mode inductor.

[0154] Furthermore, in some embodiments, the anti-electromagnetic interference device 30 further includes a mounting box, and the anti-electromagnetic interference circuit board 31, the first capacitor 32, the resistor 33, and the inductor 34 are all disposed within the mounting box 36. In one embodiment, the mounting box 36 is a rectangular box, and the inner wall surface of the grip portion 11 includes at least a mounting plane, and the mounting box 36 is fixed to the mounting plane.

[0155] It should be noted that if control assembly 20 includes control box 24 and anti-electromagnetic interference device 30 includes mounting box 36, then the minimum distance between anti-electromagnetic interference device 30 and control assembly 20 refers to the minimum distance between control box 24 and mounting box 36. If control assembly 20 does not include control box 24 or anti-electromagnetic interference device 30 does not include mounting box 36, the minimum distance is calculated based on the boundaries of the circuit boards in circuit board assembly 21 or anti-electromagnetic interference circuit board 31, rather than the specific circuit components on the circuit boards.

[0156] In one embodiment, the minimum distance between the circuit board assembly 21 and the anti-electromagnetic interference circuit board 31 is greater than or equal to 5 mm. In one embodiment, the minimum distance between the circuit board assembly 21 and the anti-electromagnetic interference circuit board 31 is greater than or equal to 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or 45 mm. The minimum distance between the circuit board assembly 21 and the anti-electromagnetic interference circuit board 31 can be 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or 45 mm.

[0157] In some embodiments, continue to refer to Figure 27 As shown, the anti-electromagnetic interference device 30 also includes an AC socket 35, which is installed on the anti-electromagnetic interference circuit board 31. The anti-electromagnetic interference device 30 is arranged near the rear end of the casing 10, and the power cord 17 passes through the rear end of the casing 10 and can be directly electrically connected to the AC socket 35.

[0158] like Figure 21As shown, the speed regulator 40 is used to adjust the speed of the brushless motor 14. In some embodiments, the speed regulator 40 and the control assembly 20 at least partially overlap along the extension direction of the grip portion 11. This arrangement makes the internal structure of the power tool compact, which is conducive to miniaturization of the power tool.

[0159] Continue to refer to Figure 21 and Figure 28 As shown, the power tool also includes a motor switch 18 for the user to operate to control the start and stop of the brushless motor 14. The motor switch 18 can be retractably installed under the grip 11. By pressing the motor switch 18, the brushless motor 14 can be powered on and off.

[0160] In some embodiments, the motor switch 18 is disposed between the electromagnetic interference prevention device 30 and the control assembly 20. In some embodiments, the speed regulator 40 is located between the motor switch 18 and the brushless motor 14.

[0161] like Figure 21 As shown, the arrangement of the entire power tool from back to front is: power cord 17 → anti-electromagnetic interference device 30 → motor switch 18 → speed regulator 40 → control component 20 → brushless motor 14 → transmission mechanism 15 → output shaft 12 and working accessories 13.

[0162] The brushless motor 14, control component 20 and anti-electromagnetic interference device 30 will generate a large amount of heat during operation. In order to improve the heat dissipation effect of the power tool, multiple ventilation holes are provided on the casing 10 so that air can form airflow inside and outside the power tool under the action of the electric fan to improve the heat dissipation effect.

[0163] In one embodiment, Figure 29 and Figure 30 As shown, the housing 10 is formed with a first air vent 104 located in front of the brushless motor 14, a second air vent 105 located at the control assembly 20, and a third air vent 106 located at the rear end of the grip 11. The fan 16 operates to form a heat dissipation airflow flowing in from the first air vent 104 and out from the second and third air vents 105, 106. Because the fan 16 is located between the brushless motor 14 and the control assembly 20, air enters from the front of the brushless motor 14 and exits from the rear of the control assembly 20 and the rear end of the grip 11. The air drawn in by the fan 16 cools the circuit board of the control assembly 20 and the brushless motor 14.

[0164] In one embodiment, Figure 29 and Figure 31As shown, the housing 10 is formed with a first air vent 104 located in front of the brushless motor 14, a second air vent 105 located at the control assembly 20, a third air vent 106 located at the rear end of the grip 11, and at least one fourth air vent 107 radially opposite the fan 16. The fan 16 acts to form a heat dissipation airflow flowing in from the first air vent 104, the second air vent 105, and the third air vent 106, and flowing out from the fourth air vent 107. Because the fan 16 is located between the brushless motor 14 and the control assembly 20, air is drawn in from three locations: in front of the brushless motor 14, behind the control assembly 20, and at the rear end of the grip 11, and air is discharged in a radial direction from the fan 16. The air drawn in from the left and right sides of the fan 16 enables efficient cooling of the circuit board of the control assembly 20 and the brushless motor 14.

[0165] In a specific embodiment, a plurality of fourth air outlets 107 are provided, and the plurality of fourth air outlets 107 are arranged around the circumference of the housing 10 , thereby achieving multiple air outlets and further improving the heat dissipation effect.

[0166] In a specific embodiment, the air inlet direction of the third air vent 106 can be flexibly set according to needs. For example, the air inlet direction of the third air vent 106 can be parallel to the central axis of the grip portion 11, or perpendicular to the central axis of the grip portion 11. Of course, the air inlet direction of the third air vent 106 can be at other angles to the central axis of the grip portion 11. In addition, multiple third air vents 106 are provided, with one third air vent 106 having an air inlet direction parallel to the central axis of the grip portion 11 and another third air vent 106 having an air inlet direction perpendicular to the central axis of the grip portion 11.

[0167] Through the technical solution introduced in this application, the length of the AC polishing machine using the brushless motor 14 in the front-to-back direction is limited. Figure 9 As shown, the distance from the tail of the housing 10 to the center line of the output shaft 12 is a first length L3, and the first length L3 is less than or equal to 450 mm. In some embodiments, the first length L3 is less than or equal to 430 mm. In some embodiments, the first length L3 is less than or equal to 410 mm. In some embodiments, the first length L3 is less than or equal to 400 mm. In some embodiments, the first length L3 is less than or equal to 390 mm. In some embodiments, the first length L3 is less than or equal to 380 mm. It should be noted that the first length L3 refers to the distance of the output shaft 12 that does not include the eccentricity. The output shaft 12 can be installed with an eccentric block with an eccentric structure, and then the polishing disk is installed. In other words, the first length L3 here does not include the eccentricity.

[0168] Continue to refer to Figure 9As shown, the distance from the rear end of the housing 10 to the front end of the stator 142 is a second length L4, and the first length L4 is less than or equal to 280 mm. In one embodiment, the second length L4 is 279 mm; in one embodiment, the second length L4 is 275 mm; and in one embodiment, the second length L4 is 270 mm.

[0169] Continue to refer to Figure 9 As shown, the distance from the rear end of the housing 10 to the head end of the housing 10 is the overall length L5 of the power tool, and the overall length L5 of the power tool is less than or equal to 450 mm. In one embodiment, the overall length L5 of the power tool is 446 mm; in one embodiment, the overall length L5 of the power tool is 440 mm; in one embodiment, the overall length L5 of the power tool is 420 mm; and in one embodiment, the overall length L5 of the power tool is 400 mm.

[0170] Continue to refer to Figure 3 As shown, the maximum height of the power tool at the motor switch 18 is a first height D3, which is less than or equal to 63 mm. The height of the power tool housing 10 at the motor switch 18 is a second height D4, which is less than or equal to 52 mm. It should be noted that the first height D3 is the sum of the second height D4 and the height of the motor switch 18 protruding from the housing 10.

[0171] The above shows and describes the basic principles, main features and advantages of this application. Those skilled in the art should understand that the above embodiments do not limit this application in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of protection of this application.

Claims

1. An AC polishing machine, comprising: Output shaft, used to drive the working accessories to move; a housing, the housing forming a grip portion for a user to hold; control assemblies, including circuit board assemblies and circuit components; Anti-electromagnetic interference devices, used to suppress electromagnetic interference; It is characterized by further comprising: A brushless motor, provided with or connected to a motor shaft, wherein the nominal power of the brushless motor is greater than 500W and less than 2500W; A transmission mechanism, disposed between the motor shaft and the output shaft and realizing transmission; The distance from the tail of the housing to the center line of the output shaft is a first length L3, and the first length L3 is less than or equal to 450 mm.

2. The AC polishing machine according to claim 1, wherein: The circuit board assembly includes at least a first circuit board and a second circuit board. When viewed from a direction perpendicular to the first circuit board, the first circuit board and the second circuit board at least partially overlap.

3. The AC polishing machine according to claim 1, wherein: The circuit board assembly includes at least a first circuit board and a second circuit board. When viewed in a direction perpendicular to the first circuit board, the first circuit board and the second circuit board at least partially overlap, the area of ​​the first circuit board is greater than or equal to the area of ​​the second circuit board, and the maximum length L of the control assembly along the extension direction of the control assembly is less than or equal to 75 mm.

4. The AC polishing machine according to claim 2 or 3, wherein: The working attachment is used to clamp the polishing disc; the projection area of ​​the first circuit board on the polishing plane of the polishing disc is less than or equal to 3000 square millimeters; the projection area of ​​the second circuit board on the polishing plane of the polishing disc is less than or equal to 2500 square millimeters.

5. The AC polishing machine according to claim 1, wherein: The anti-electromagnetic interference device includes an anti-electromagnetic interference circuit board, and the anti-electromagnetic interference circuit board is configured as a single-board structure.

6. The AC polishing machine according to claim 5, wherein: The maximum length of the anti-electromagnetic interference circuit board is less than 65 mm; Alternatively, the maximum length of the anti-electromagnetic interference circuit board is less than 55 mm; Alternatively, the maximum length of the anti-electromagnetic interference circuit board is less than 45 mm.

7. The AC polishing machine according to claim 5, wherein: The area of ​​the anti-electromagnetic interference circuit board is less than or equal to 1500 plane millimeters.

8. The AC polishing machine according to claim 1, wherein: The AC polishing machine further comprises a fan, which is sleeved on the motor shaft and located between the brushless motor and the control assembly.

9. The AC polishing machine according to claim 8, wherein: The housing is formed with a first air outlet located in front of the brushless motor, a second air outlet located at the control component, and a third air outlet located at the rear end of the grip portion. Under the action of the fan, a heat dissipation airflow is formed that flows in from the first air outlet and flows out from the second air outlet and the third air outlet.

10. The AC polishing machine according to claim 8, wherein: The housing is formed with a first air outlet located in front of the brushless motor, a second air outlet located at the control component, a third air outlet located at the rear end of the grip portion, and at least one fourth air outlet radially opposite to the fan. Under the action of the fan, a heat dissipation airflow is formed flowing in from the first air outlet, the second air outlet, and the third air outlet and flowing out from the fourth air outlet.

11. The AC polishing machine according to claim 1, wherein: The brushless motor includes a first bearing supported at a front end of the motor shaft, wherein the first bearing at least partially overlaps with a stator of the brushless motor in an axial direction of the motor shaft.

12. The AC polishing machine according to claim 8, wherein: The brushless motor includes a second bearing supported at a rear end of the motor shaft, wherein the second bearing at least partially overlaps with the fan in an axial direction of the motor shaft.

13. The AC polishing machine according to claim 1, wherein: The control assembly includes a circuit board assembly, and the plane where the circuit board assembly is located is arranged at an angle to the axis of the motor shaft.

14. The AC polishing machine according to claim 13, wherein: The plane where the circuit board assembly is located is substantially perpendicular to the axis of the motor shaft.

15. The AC polishing machine according to claim 13, wherein: The circuit board assembly includes at least one circuit board, and the circuit board is a non-circular plate with a side wall formed by an arc surface and a plane.

16. The AC polishing machine according to claim 13, wherein: The circuit board assembly includes a plurality of circuit boards, and the plurality of circuit boards are all perpendicular to the axial direction of the motor shaft.

17. The AC polishing machine according to claim 1, wherein: The circumference D1 of the gripping portion along the midline is less than 135 mm.

18. The AC polishing machine according to claim 1, wherein: The circumference D2 of the motor housing of the brushless motor at the stator midline is less than or equal to 235 mm.

19. The AC polishing machine according to claim 1, wherein: The power of the brushless motor is greater than or equal to 1000W and less than or equal to 2000W.

20. The AC polishing machine according to claim 1, wherein: The stack length of the brushless motor is greater than or equal to 10 mm and less than or equal to 50 mm, and the outer diameter of the brushless motor is greater than or equal to 30 mm and less than or equal to 65 mm.

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