Electric tool and motor

Abstract

The invention provides an electric tool and a motor, the electric tool comprises a motor, a power supply device and an output part, the motor is used for providing power for the electric tool, the motor comprises a stator and a rotor rotating relative to the stator, and the rotor comprises a rotor iron core and magnetic steel arranged on the rotor iron core; the power supply device is at least electrically connected with the motor; the output part is driven by the motor; the rotor core comprises limiting parts which are arranged at intervals in the direction of the axis L, and the limiting parts are used for fixing the magnetic steel. By adopting the technical scheme, the mass of the motor is reduced, the loss of the motor is reduced, and the efficiency of the motor is improved.

Description

Technical Field

[0001] The present application relates to an electric tool, and in particular to an electric tool and a motor in which magnets are fixed by limiting portions arranged at intervals along the axial direction of a rotor core. Background Art

[0002] High-power electric tools such as chain saws and snow blowers are becoming more and more popular in the market. High-power electric tools require motors with higher power and higher efficiency. Therefore, the motors of high-power electric tools are developing in the direction of high power density, miniaturization, and lightweight. For high-frequency motors, the motor core loss accounts for a large proportion, which is the main reason for heating, causing a sharp increase in the internal heat of the motor, resulting in abnormal motor temperature rise and affecting the motor life.

[0003] With better heat dissipation performance, outer rotor motors are more suitable for high-power power tools. The permanent magnets of outer rotor motors are outside the stator and between the stator and the housing. When the rotor runs at high speed, the permanent magnets are subject to centrifugal force, electromagnetic force and other forces, and there is a risk of falling off the stator. Therefore, it is necessary to increase the anti-falling measures of the permanent magnets. In addition, it is also particularly important for production not to bring additional production and process costs. Summary of the invention

[0004] The present application provides an electric tool and a motor that are safer to use. The electric tool can solve the problem of permanent magnets falling off from the stator in an outer rotor motor without incurring additional production and process costs.

[0005] To achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect, the present application provides an electric tool, the electric tool comprising:

[0007] A motor, used to provide power for the electric tool, the motor comprising a stator and a rotor rotating relative to the stator, the rotor comprising a rotor core and a magnet disposed on the rotor core;

[0008] a power supply device, electrically connected to at least the motor;

[0009] an output portion, driven by the motor;

[0010] The rotor core includes limiting portions spaced apart along the axis L, and the limiting portions are used to fix the magnetic steel.

[0011] In some embodiments, the limiting portion includes a first limiting portion and a second limiting portion, one of the first limiting portion and the second limiting portion is located at the head portion of the rotor core, and the other is located at the tail portion of the rotor core.

[0012] In some embodiments, the limiting portion includes a first limiting portion and a second limiting portion, one of the first limiting portion and the second limiting portion is located in the middle of the rotor core, and the other is located at the head and / or tail of the rotor core.

[0013] In some embodiments, the limiting portion includes a first limiting portion, and the thickness of the first limiting portion ranges from 1 mm to 2 mm; and / or

[0014] The limiting portion includes a second limiting portion, and the thickness of the second limiting portion ranges from 1 mm to 2 mm.

[0015] In some embodiments, the limiting portion forms a dovetail groove, and the magnetic steel is inserted into the dovetail groove along the axis L of the rotor core.

[0016] In some embodiments, the limiting portion is lower than the magnetic steel in the circumferential direction.

[0017] In some embodiments, the magnetic steel is fan-shaped, including an inner arc and an outer arc, the inner arc and the outer arc are concentrically arranged, and the distance between the center of the inner arc or the outer arc and the axis L of the rotor core is in the range of 50mm-100mm.

[0018] In some embodiments, the rotor core includes a plurality of laminations stacked along an axis L, and the laminations are made of silicon steel.

[0019] In some embodiments, the rotor further includes a fastening sleeve, which is sleeved on the outer periphery of the rotor core, and the fastening sleeve does not have the ability to conduct magnetism.

[0020] In some embodiments, the rotor further includes a first fixing member, which is fixed to one end of the rotor core, and is used to constrain the magnetic steel in the axial and circumferential directions.

[0021] In some embodiments, the rotor further includes a second fixing member, which is fixed to the other end of the rotor core, and the second fixing member is used to radially constrain the magnetic steel.

[0022] In some embodiments, the rated output power of the motor ranges from 3000W to 7000W.

[0023] In some embodiments, the maximum speed range of the motor is greater than or equal to 20,000 rpm.

[0024] In some embodiments, the electric tool includes at least one of a chain saw, a snow blower, a pruner, a lawn mower, and a DC fan.

[0025] In a second aspect, the present application provides an electric tool, the electric tool comprising:

[0026] A motor, used to provide power for the electric tool, the motor comprising a stator and a rotor rotating relative to the stator and at least partially disposed outside the stator, the rotor comprising a rotor core and a magnet disposed on the rotor core;

[0027] a power supply device, electrically connected to at least the motor;

[0028] an output portion, driven by the motor;

[0029] The rotor core includes a plurality of laminations arranged along the axis L, and the plurality of laminations have at least two different shapes so that the plurality of laminations at least include a first lamination having a first shape and a second lamination having a second shape.

[0030] In some embodiments, a projection shape of the first laminate on a first plane is different from a projection shape of the second laminate on the first plane; and the first plane is perpendicular to the output axis.

[0031] In a third aspect, the present application provides an electric tool, the electric tool comprising:

[0032] A motor, used to provide power for the electric tool, the motor comprising a stator and a rotor rotating relative to the stator, the rotor comprising a rotor core and a magnet disposed on the rotor core;

[0033] a power supply device, electrically connected to at least the motor;

[0034] an output portion, driven by the motor;

[0035] A limiting portion for fixing the magnetic steel is formed on the inner wall of the rotor core, and the ratio of the total length of the limiting portion in the direction of the axis L to the length of the magnetic steel in the direction of the axis L is in the range of 0.01-0.9.

[0036] In some embodiments, the ratio of the total length of the limiting portion in the direction of the axis L to the length of the magnetic steel in the direction of the axis L is in the range of 0.1-0.2.

[0037] In some embodiments, the number of the limiting parts is one or more.

[0038] In a fourth aspect, the present application provides an electric tool, the electric tool comprising:

[0039] A stator and a rotor rotating relative to the stator, wherein the rotor comprises a rotor core and a magnetic steel arranged on the rotor core;

[0040] The rotor core includes limiting portions spaced apart along the axis L, and the limiting portions are used to fix the magnetic steel.

[0041] In some embodiments, the motor is an outer rotor motor.

[0042] In some embodiments, the rated power of the motor is greater than or equal to 1000W and less than or equal to 7000W.

[0043] The beneficial effects of this application are:

[0044] The present application provides an electric tool and a motor. The rotor core in the motor of the electric tool includes limit parts arranged at intervals along the axis L. The limit parts are used to fix the magnets, thereby solving the problem of the magnets falling off the stator. Compared with the limit parts of the integrated structure in the prior art, the weight of the limit parts arranged at intervals is effectively reduced, thereby reducing motor losses and improving motor efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the structure of the power tool;

[0046] Figure 2 It is a schematic diagram of the motor structure;

[0047] Figure 3 is a schematic structural diagram of a stator and a rotor in one embodiment;

[0048] Figure 4 is a schematic structural diagram of a stator and a magnetic steel in a first perspective in one embodiment;

[0049] Figure 5 yes Figure 4 The enlarged view of point A in the middle;

[0050] Figure 6 is a schematic structural diagram of a stator and a magnetic steel in a second perspective in one embodiment;

[0051] Figure 7 is a schematic cross-sectional structural diagram of a motor in one embodiment;

[0052] Figure 8 is a schematic diagram of the classification of a motor in one embodiment;

[0053] Fig. 9 is a schematic diagram of the internal structure of a motor in another embodiment;

[0054] Fig.10 is a schematic structural diagram of a rotor from a first perspective in another embodiment;

[0055] Fig.11 is a schematic diagram of the exploded structure of a rotor in another embodiment;

[0056] Fig.12 yes Fig.11 The enlarged view of point B in the middle;

[0057] Fig.13 It is a schematic structural diagram of a rotor from a second viewing angle in another embodiment.

[0058] 100, chain saw; 10, housing; 11, rear handle; 111, first switch; 112, second switch; 12, front handle; 13, guard; 14, joint; 15, right housing; 16, left housing; 17, main housing; 21, saw chain; 22, guide plate; 30, power supply device;

[0059] 200, motor; 210, stator; 220, rotor; 221, rotor core; 2211, first limiting portion; 2212, second limiting portion; 2213, dovetail groove; 2214, first lamination; 22141, first protrusion; 22142, second protrusion; 2215, second lamination; 222, magnet; 223, first fixing member; 2231, first connecting portion; 2232, first fixing portion; 224, second fixing member; 2241, second connecting portion; 2242, second fixing portion; 225, clamping sleeve; 226, output shaft. DETAILED DESCRIPTION

[0060] Before any embodiments of the 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 above drawings.

[0061] In this application, the terms "comprises", "includes", "has" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0062] In this application, the term "and / or" is a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects before and after are in an "and / or" relationship.

[0063] In the present 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, direct connection refers to two parts or components being connected together without the need for an intermediate piece, and indirect connection refers to two parts or components being connected to at least one intermediate piece respectively, and the two parts or components being connected via the intermediate piece. In addition, "connect" and "couple" are not limited to physical or mechanical connections or couplings, and may include electrical connections or couplings.

[0064] In the present application, it will be understood by those of ordinary skill 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 tolerances caused by manufacturing, assembly, and use associated with a specific value, and the like. 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).

[0065] In this application, it will be understood by those skilled in the art that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0066] 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 another element "upper" or "lower", but also indirectly connected to another 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, the bottom can include directly below, lower left, lower right, lower front, and lower back, etc.

[0067] Figure 1The specific embodiment of the electric tool in the present application is shown. In fact, the motor taught in the present application can be applied to handheld electric tools such as electric drills, electric wrenches, electric screwdrivers, electric hammer drills, electric circular saws, sanders, bench tools such as table saws, and outdoor tools such as lawn mowers, snow blowers, mowers, electric shears, pruning machines, chain saws 100, and pole saws. The motor of the present application is also applicable to DC fans, high-pressure cleaners or all-terrain vehicles. Obviously, the following embodiments are part of the embodiments of the present application, not all of the embodiments.

[0068] See also Figure 1 As shown, the chain saw 100 includes a housing 10, a saw chain 21, a sprocket supported in the housing 10 and capable of driving the saw chain 21 to move, and a guide plate 22 for supporting and guiding the saw chain 21. In some embodiments, the housing 10 includes a right housing 15 and a left housing 16, which are assembled in the left and right directions to form the housing 10 and a first accommodation space. The housing 10 includes a main housing portion 17, which is formed or connected with a rear handle 11 for the user to hold, and a front handle 12 for the user to lift and cooperate with the rear handle 11 to operate the chain saw 100. In some embodiments, a switch for controlling the operating state of the chain saw 100 is connected to the rear handle 11. Specifically, the switch includes a first switch 111 and a second switch 112. When the user presses the first switch 111 and the second switch 112 at the same time, the chain saw 100 can be started, thereby avoiding accidents caused by the user accidentally touching the first switch 111 to start the chain saw 100 when holding the chain saw 100. In some embodiments, the second switch 112 is usually used as a safety start switch, and the first switch 111 is usually used as a power-on and speed adjustment switch. It is understood that when using, the user presses the second switch 112 with the thumb and presses the first switch 111 with the index finger or middle finger to start and adjust the speed of the chain saw 100.

[0069] The chain saw 100 further includes a guard 13 disposed on the front side of the front handle 12. The guard 13 is used to protect the user from being cut by the saw chain 21 due to the recoil force when the user is operating the chain saw 100. When the chain saw 100 is in operation, some splashes (such as wood chips) may be generated to scratch the surface of the user's hand holding the front handle 12.

[0070] The chain saw 100 also includes a power supply device 30 for providing the chain saw 100 with the electrical energy required for operation. The power supply device 30 includes a battery pack, which is detachably connected to the joint 14 formed by the housing 10. It should be understood that the power supply device 30 is not limited to the scenario of using the battery pack, and can also be powered by AC power, AC power, and corresponding rectification, filtering and voltage regulation circuits to realize power supply to various circuit elements. In some embodiments, the power supply device 30 includes multiple battery packs to provide the chain saw 100 with a longer battery life and a larger output power. Specifically, the total energy of the power supply device 30 is greater than or equal to 20Wh. The maximum rated voltage of the power supply device 30 is set to be greater than or equal to 40V and less than or equal to 100V.

[0071] See also Figure 1 and Figure 2 As shown, the chain saw 100 also includes a first drive unit for outputting power. In this embodiment, the first drive unit includes at least a motor, which can also be referred to as a motor 200. For ease of description, the motor 200 is used as an example for description. The motor 200 is arranged in the main housing portion 17. Specifically, the motor 200 has an output shaft 226, and the output shaft 226 is used to drive the sprocket to rotate. The sprocket drives the saw chain 21, and the saw chain 21 surrounds the edge of the guide plate 22 and can be cyclically guided by the guide plate 22. The guide plate 22 is basically distributed in the front-to-back direction, one end of the guide plate 22 is supported on the housing 10, and the other end extends out of the housing 10 along the longitudinal direction of the housing 10. For the chain saw 100 driven by the motor 200, especially the chain saw 100 driven by direct current, due to the structural limitations of the chain saw 100 itself, the overall weight is heavy after the power supply device 30 is installed. In order to reduce the fatigue of the user when operating the chain saw 100 for a long time, it is necessary to set the center of gravity of the chain saw 100 to a position close to the front handle 12. Specifically, the motor 200 and the saw chain 21 of the chain saw 100 are disposed at the front end of the chain saw 100. The power supply device 30 is disposed at the rear end of the chain saw 100 relative to the motor 200. The rear handle 11 is disposed on the upper side of the power supply device 30.

[0072] In some embodiments, the rated output power of the motor 200 is in the range of 3000W-7000W, and the maximum speed range is greater than or equal to 20000rpm. The rotor diameter of the motor 200 is greater than or equal to 50mm and less than or equal to 105mm. Optionally, the rotor diameter of the motor 200 is greater than or equal to 80mm and less than or equal to 95mm. The rated power of the motor 200 is greater than or equal to 1000W and less than or equal to 7000W.

[0073] See also Figures 2 to 8As shown, regarding the structure of the motor 200, in this embodiment, the motor 200 includes a stator 210 and a rotor 220 at least partially disposed outside the stator 210 and rotating relative to the stator 210, and the rotor 220 includes a fastening sleeve 225 and a magnetic steel 222 disposed in the fastening sleeve 225. The motor 200 is electrically connected to the power supply device 30, and the motor 200 is powered by the power supply device 30. The output part includes a saw chain 21, and the saw chain 21 is directly or indirectly driven by the motor 200. Optionally, the motor 200 is configured as an outer rotor motor.

[0074] The material of the fastening sleeve 225 is a non-magnetic material, wherein the material of the fastening sleeve 225 is a non-magnetic metal material or a non-metallic material. There are a plurality of magnetic steels 222, which are divided into a plurality of poles. The plurality of pole magnetic steels 222 are annular around the axis L and are connected end to end in sequence. Each pole magnetic steel 222 has a plurality of magnetic steels 222 with different magnetic pole directions. Compared with existing magnetic conductive materials, non-magnetic conductive materials have more choices and a smaller relative density, making the weight of the motor 200 lighter, thereby reducing the weight of the overall electric tool and improving the convenience of use.

[0075] In some embodiments, see Figure 3 and Figure 4 As shown, the rotor includes a fastening sleeve 225 and a plurality of magnets 222 arranged in the fastening sleeve 225. The plurality of magnets 222 are arranged in a ring shape around the axis L on the inner wall of the fastening sleeve 225. The plurality of magnets 222 form a plurality of magnetic poles, and the magnetizing directions of at least two magnets 222 in each magnetic pole are different. In this way, compared with the traditional motor architecture, the magnetizing direction of the magnet 222 is set in the present application, which can greatly increase the magnetic field strength on one side of the magnet 222 and greatly weaken the other side, effectively reducing the volume of the motor and improving the power density of the motor. Optionally, the magnet 222 in the present application adopts a Halbach magnet array.

[0076] See also Figure 5 As shown, three magnets a, b and c constitute a magnetic pole, wherein the magnetization directions of the three magnets 222 in each magnetic pole are different. The direction of the arrow is the magnetization direction of the magnet 222. It should be noted that the size of the magnet 222 in each magnetic pole can also be set to different sizes.

[0077] In some embodiments, each pole magnetic steel 222 has M magnetic steels 222, and M is greater than or equal to 2 and less than or equal to 7. The number of poles of the magnetic steel 222 can be set according to actual needs and is not limited thereto. In some embodiments, each pole magnetic steel 222 has M magnetic steels 222, and M is greater than or equal to 4 and less than or equal to 5. In this embodiment, each pole magnetic steel 222 has five magnetic steels 222. Among them, the magnetic pole direction of each magnetic steel 222 in each pole magnetic steel 222 is different, and the specific magnetic pole direction can be set according to actual conditions. The method for determining the magnetic pole direction is well known to those skilled in the art and will not be repeated here. The magnetic lines of force are closed only between the stator 210, the air gap, and the magnetic steel 222 to form a loop.

[0078] In some embodiments, the cross-sectional shape of the winding on the stator 210 is polygonal or circular. Exemplarily, the cross-sectional shape of the winding on the stator 210 is triangular, quadrilateral or pentagonal. When the cross-sectional shape of the winding on the stator 210 is quadrilateral, it can be rectangular or square. In some embodiments, the cross-sectional shape of the winding on the stator 210 can be hexagonal, heptagonal or even octagonal.

[0079] In some embodiments, the winding method on the stator 210 is flat-wound or vertical-wound.

[0080] The output terminal of the winding on the stator 210 is led out through a busbar or a PCB. Among them, the way of leading out through the PCB is simple to assemble, has good interchangeability and maintainability, and is suitable for standardized mass production. The way of leading out through the busbar has good connection stability and strong vibration resistance, and is suitable for harsh working conditions. When using it, the structure and application scenarios of the motor 200 can be considered as a whole, and the way of leading out the output terminal can be reasonably selected.

[0081] In some embodiments, the material of the stator 210 is an amorphous alloy or a nanocrystalline material. Amorphous alloys have excellent performance and simple process, and are superior to silicon steel sheets in terms of magnetic permeability and iron loss. Nanocrystals can greatly improve the performance and efficiency of the motor 200 by virtue of their excellent physical and chemical properties.

[0082] In some embodiments, the angle between the two opposite faces of any two adjacent magnetic steels 222 is A, and A is greater than or equal to 0° and less than or equal to 5°. With the above-mentioned angle setting, the gap between the two adjacent magnetic steels 222 can be appropriately adjusted, thereby reducing the manufacturing difficulty of the magnetic steel 222 and reducing the cost. In some embodiments, the angle between the two opposite faces of any two adjacent magnetic steels 222 is A, and A is equal to 0°. This setting makes each magnetic steel 222 a fan-shaped structure, maximizes the volume of the magnetic steel 222, and helps to improve the power density of the motor 200.

[0083] See also Figure 7 and Figure 8 As shown, in some embodiments, the rotor 220 further includes a first fixing member 223, which is fixed to one end of the fastening sleeve 225, and the first fixing member 223 is used to axially and / or circumferentially constrain the magnetic steel 222. This arrangement makes the magnetic steel 222 more stable relative to the stator 210, and improves the safety of use. Specifically, the first fixing member 223 includes a first connecting portion 2231 and a first fixing portion 2232 connected to the first connecting portion 2231, the first connecting portion 2231 is connected to the fastening sleeve 225, and the first fixing portion 2232 is used to constrain the magnetic steel 222. In this embodiment, the first fixing portion 2232 is strip-shaped, and is provided with a plurality of first fixing portions 2232, and the plurality of first fixing portions 2232 are evenly arranged around the axis L, and every two adjacent first fixing portions 2232 and the first connecting portion 2231 form a fixing groove, and one end of the magnetic steel 222 is located in the fixing groove, and is limited circumferentially by the two side walls of the fixing groove and axially by the first connecting portion 2231. The first fixing member 223 in this embodiment is only applicable to implementations in which the angle between adjacent magnetic steels 222 is not zero.

[0084] In this embodiment, the first connecting portion 2231 and the first fixing portion 2232 are integrally formed.

[0085] The rotor 220 further includes a second fixing member 224, which is fixed to the other end of the fastening sleeve 225, and is used to radially constrain the magnetic steel 222. Specifically, the second fixing member 224 is provided with a second connecting portion 2241 and a second fixing portion 2242 provided on the second connecting portion 2241, the second connecting portion 2241 is connected to the fastening sleeve 225, and the second fixing portion 2242 is used to constrain the magnetic steel 222. In this embodiment, the second fixing portion 2242 is a limiting groove provided on the second connecting portion 2241, and a plurality of limiting grooves are provided, and the plurality of limiting grooves are evenly distributed around the axis L, and the limiting groove has a groove bottom, two circumferential side walls and two radial side walls, and the other end of the magnetic steel 222 is located in the limiting groove, and the magnetic steel 222 is axially limited by the groove bottom of the limiting groove, the magnetic steel 222 is circumferentially limited by the circumferential side walls of the limiting groove, and the magnetic steel 222 is radially limited by the radial side walls of the limiting groove. The first fixing member 223 in this embodiment is only applicable to the embodiment in which the angle between the magnetic steels 222 is not zero. In some embodiments, the limiting groove can be annular. The other ends of all the magnetic steels 222 are fixed in the limiting groove. In this embodiment, the bottom of the limiting groove realizes the axial limitation of the magnetic steel 222, and the radial side wall of the limiting groove radially limits the magnetic steel 222. In this embodiment, the limiting groove can be applicable to the embodiment in which the angle between the magnetic steels 222 is zero or non-zero.

[0086] In this embodiment, the second connection portion 2241 and the second connection portion 2241 are integrally formed.

[0087] exist Figure 7 and Figure 8 In the illustrated embodiment, the magnetic steel 222 may not be a Halbach magnet array.

[0088] See also Figures 9 to 13 As shown, in some embodiments, the motor 200 includes a stator 210 and a rotor 220 that rotates relative to the stator 210, and the rotor 220 includes a rotor core 221 and a magnetic steel 222 disposed on the rotor core 221; the rotor core 221 includes a limiting portion arranged at intervals along the axis L, and the limiting portion is used to fix the magnetic steel 222. Among them, the limiting portion is used to fix the magnetic steel 222, which solves the problem of the magnetic steel 222 falling off from the rotor 220. Compared with the limiting portion of the integrally arranged structure in the prior art, the weight of the limiting portion arranged at intervals is effectively reduced, thereby reducing the loss of the motor 200 and improving the efficiency of the motor 200.

[0089] In some embodiments, the limiting portion includes a first limiting portion 2211 and a second limiting portion 2212, one of the first limiting portion 2211 and the second limiting portion 2212 is located at the head of the rotor core 221, and the other is located at the tail of the rotor core 221. This arrangement can support both ends of the magnetic steel 222, thereby improving the stability of the magnetic steel 222.

[0090] In some embodiments, the limiting portion includes a first limiting portion 2211 and a second limiting portion 2212, one of which is located in the middle of the rotor core 221, and the other is located at the head and / or tail of the rotor core 221. In this embodiment, three embodiments can be set with respect to the positional relationship between the first limiting portion 2211 and the second limiting portion 2212. In a first embodiment, the limiting portion includes a first limiting portion 2211 and a second limiting portion 2212, one of which is located in the middle of the rotor core 221, and the other is located at the head of the rotor core 221. In a second embodiment, the limiting portion includes a first limiting portion 2211 and a second limiting portion 2212, one of which is located in the middle of the rotor core 221, and the other is located at the tail of the rotor core 221. In the third embodiment, the limiting part includes a first limiting part 2211 and a second limiting part 2212, one of the first limiting part 2211 and the second limiting part 2212 is located in the middle of the rotor core 221, and the other is located at the head and tail of the rotor core 221. In the third embodiment, exemplarily, the first limiting part 2211 is located in the middle of the rotor core 221, and there are two second limiting parts 2212, and the two second limiting parts 2212 are respectively located at the head and tail of the rotor core 221. This arrangement allows the magnetic steel 222 to be supported at the head, middle and tail, and is more secure.

[0091] In some embodiments, the limiting portion includes a first limiting portion 2211, and the thickness of the first limiting portion 2211 ranges from 1mm to 2mm. In this embodiment, the thickness of the first limiting portion 2211 refers to the dimension of the first limiting portion 2211 along the axis L direction. The limiting portion includes a second limiting portion 2212, and the thickness of the second limiting portion 2212 ranges from 1mm to 2mm. In this embodiment, the thickness of the second limiting portion 2212 refers to the dimension of the second limiting portion 2212 along the axis L direction. The thickness dimensions of the first limiting portion 2211 and the second limiting portion 2212 may be the same or different. When the two are the same, they may both be 1.5mm. In other embodiments, the thickness dimensions of the first limiting portion 2211 and the second limiting portion 2212 may also both be 0.5mm, 2.1mm, 3mm or 5mm.

[0092] In some embodiments, the length of the limit portion is limited from the perspective of ratio, and the ratio of the total length of the limit portion in the direction of the axis L to the length of the magnetic steel 222 in the direction of the axis L is in the range of 0.01-0.9. In some embodiments, the ratio of the total length of the limit portion in the direction of the axis L to the length of the magnetic steel 222 in the direction of the axis L is in the range of 0.1-0.2.

[0093] In some embodiments, the number of the limiting parts is one or more. When there is one limiting part, the length of the limiting part can be appropriately larger, and when there are multiple limiting parts, the length of the limiting part can be appropriately smaller.

[0094] See also Fig.12 and Fig.13 As shown, the limiting portion forms a dovetail groove 2213, and the magnetic steel 222 is inserted into the dovetail groove 2213 along the axis L direction of the rotor core 221. The setting of the dovetail groove 2213 helps to radially limit the magnetic steel 222, that is, to prevent the magnetic steel 222 from moving in the radial direction of the rotor core 221. Specifically, the structure of the dovetail groove 2213 can be a trapezoid or a triangle. In other words, the distance between the two side walls of the dovetail groove 2213 can gradually decrease in the direction close to the axis L or first increase and then decrease.

[0095] In some embodiments, the stopper is lower than the magnetic steel 222 in the circumferential direction. In other words, in the radial direction of the motor 200, the depth dimension of the dovetail slot 2213 is smaller than the thickness dimension of the magnetic steel 222. This arrangement prevents the excessively high stopper from affecting the stator 210. Under the premise that the gap between the stator 210 and the rotor 220 remains unchanged, the thickness of the magnetic steel 222 is increased as much as possible, thereby improving the performance of the motor 200.

[0096] In some embodiments, the magnetic steel 222 is fan-shaped, including an inner arc and an outer arc, the inner arc and the outer arc are concentrically arranged, and the distance between the center of the inner arc or the outer arc and the axis L of the rotor core 221 is in the range of 50mm-100mm. This arrangement enables the magnetic steel 222 to better fit in the trapezoidal dovetail slot 2213. In other embodiments, the shape of the magnetic steel 222 is not limited to the fan-shaped, and can be arranged according to the structure of the dovetail slot 2213.

[0097] See also Fig.12 As shown, the rotor core 221 includes a plurality of laminations stacked along the axis L, and the laminations are made of silicon steel. The plurality of laminations have at least two different shapes. The laminations include a first lamination 2214 having a first shape and a second lamination 2215 having a second shape, and the projection shapes of the first lamination 2214 and the second lamination 2215 on the first plane are different. The first plane is perpendicular to the output shaft 226. The first lamination 2214 has a first protrusion 22141 and a second protrusion 22142. After a plurality of first laminations 2214 are stacked, the plurality of first protrusions 22141 form a first limiting portion 2211 or a second limiting portion 2212. The second lamination 2215 also has a second protrusion 22142. After a plurality of first laminations 2214 and a plurality of second laminations 2215 are stacked, the plurality of second protrusions 22142 form a clamping platform. The clamping platform can cooperate with the clamping groove of the fastening sleeve 225 to prevent the rotor core 221 from rotating around the axis L relative to the fastening sleeve 225. The material of the lamination can also be other materials, not limited to the above materials. The shape of the lamination can also have three or four types, not limited to the above embodiments.

[0098] The rotor 220 further includes a fastening sleeve 225, which is sleeved on the outer periphery of the rotor core 221. The fastening sleeve 225 does not have the ability to conduct magnetism. This arrangement makes the rotor core 221 composed of laminations more solid.

[0099] In some embodiments, the first fixing member 223 and the second fixing member 224 may also be fixed on the rotor core 221 .

[0100] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the above embodiments do not limit the present application in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present application.

Claims

1. An electric tool, comprising: A motor, used for providing power for the electric tool, the motor comprising a stator (210) and a rotor (220) rotating relative to the stator (210), the rotor (220) comprising a rotor core (221) and a magnetic steel (222) arranged on the rotor core (221); A power supply device (30), electrically connected to at least the motor; an output portion, driven by the motor; It is characterized in that The rotor core (221) comprises limiting portions arranged at intervals along the axis L, and the limiting portions are used to fix the magnetic steel (222).

2. The electric tool according to claim 1, characterized in that: The limiting portion comprises a first limiting portion (2211) and a second limiting portion (2212), wherein one of the first limiting portion (2211) and the second limiting portion (2212) is located at the head of the rotor core (221), and the other is located at the tail of the rotor core (221).

3. The electric tool according to claim 1, characterized in that: The limiting portion comprises a first limiting portion (2211) and a second limiting portion (2212), wherein one of the first limiting portion (2211) and the second limiting portion (2212) is located at a middle portion of the rotor core (221), and the other is located at a head portion and / or a tail portion of the rotor core (221).

4. The electric tool according to claim 1, characterized in that: The limiting portion comprises a first limiting portion (2211), the thickness of the first limiting portion (2211) is in the range of 1 mm to 2 mm; and / or The limiting portion comprises a second limiting portion (2212), and the thickness of the second limiting portion (2212) ranges from 1 mm to 2 mm.

5. The electric tool according to claim 1, characterized in that: The limiting portion forms a dovetail groove (2213), and the magnetic steel (222) is inserted into the dovetail groove (2213) along the axis L direction of the rotor core (221).

6. The electric tool according to claim 1, characterized in that: The limiting portion is lower than the magnetic steel (222) in the circumferential direction.

7. The electric tool according to claim 1, characterized in that: The magnetic steel (222) is fan-shaped, including an inner arc and an outer arc, the inner arc and the outer arc are concentrically arranged, and the distance between the center of the inner arc or the outer arc and the axis L of the rotor core (221) is in the range of 50mm-100mm.

8. The electric tool according to claim 1, characterized in that: The rotor core (221) comprises a plurality of laminations stacked along an axis L, and the laminations are made of silicon steel.

9. The electric tool according to claim 1, characterized in that: The rotor (220) further comprises a fastening sleeve (225), wherein the fastening sleeve (225) is sleeved on the outer periphery of the rotor core (221), and the fastening sleeve (225) does not have the ability to conduct magnetism.

10. The electric tool according to claim 1, characterized in that: The rotor (220) further comprises a first fixing member (223), wherein the first fixing member (223) is fixed to one end of the rotor core (221), and the first fixing member (223) is used to axially and circumferentially constrain the magnetic steel (222).

11. The electric tool according to claim 1, characterized in that: The rotor (220) further comprises a second fixing member (224), wherein the second fixing member (224) is fixed to the other end of the rotor core (221), and the second fixing member (224) is used to radially constrain the magnetic steel (222).

12. The electric tool according to claim 1, characterized in that: The rated output power of the motor ranges from 3000W to 7000W.

13. The electric tool according to claim 1, characterized in that: The maximum speed range of the motor is greater than or equal to 20,000 rpm.

14. The electric tool according to claim 1, characterized in that: The electric tool comprises at least one of a chain saw (100), a snow blower, a pruner, a lawn mower, and a DC fan.

15. An electric tool comprising: A motor, used for providing power for the electric tool, the motor comprising a stator (210) and a rotor (220) rotating relative to the stator (210) and at least partially arranged outside the stator, the rotor (220) comprising a rotor core (221) and a magnetic steel (222) arranged on the rotor core (221); A power supply device (30), electrically connected to at least the motor; an output portion, driven by the motor; It is characterized in that The rotor core (221) comprises a plurality of laminations arranged along the axis L, wherein the plurality of laminations have at least two different shapes so that the plurality of laminations at least include a first lamination (2214) having a first shape and a second lamination (2215) having a second shape.

16. The electric tool according to claim 15, characterized in that: The projection shape of the first laminate (2214) on the first plane is different from the projection shape of the second laminate (2215) on the first plane; the first plane is perpendicular to the output shaft (226).

17. An electric tool comprising: A motor, used for providing power for the electric tool, the motor comprising a stator (210) and a rotor (220) rotating relative to the stator (210), the rotor (220) comprising a rotor core (221) and a magnetic steel (222) arranged on the rotor core (221); A power supply device (30), electrically connected to at least the motor; an output portion, driven by the motor; It is characterized in that A limiting portion for fixing the magnetic steel (222) is formed on the inner wall of the rotor core (221), and the ratio of the total length of the limiting portion in the direction of the axis L to the length of the magnetic steel (222) in the direction of the axis L is in the range of 0.01-0.

9.

18. The electric tool according to claim 17, characterized in that: The ratio of the total length of the limiting portion in the direction of the axis L to the length of the magnetic steel (222) in the direction of the axis L is in the range of 0.1-0.

2.

19. The electric tool according to claim 17, characterized in that: The number of the limiting parts is one or more.

20. A motor comprising: A stator (210) and a rotor (220) rotating relative to the stator (210), wherein the rotor (220) comprises a rotor core (221) and a magnetic steel (222) disposed on the rotor core (221); It is characterized in that The rotor core (221) comprises limiting portions arranged at intervals along the axis L, and the limiting portions are used to fix the magnetic steel (222).

21. The motor according to claim 20, characterized in that The motor is an outer rotor motor.

22. The motor according to claim 20, characterized in that The rated power of the motor is greater than or equal to 1000W and less than or equal to 7000W.

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