阅读说明：本技术 电动工具及其电机 (Electric tool and motor thereof ) 是由 杨青松 于 2019-03-14 设计创作，主要内容包括：本发明公开了一种电动工具以及电机,所述电动工具包括壳体组件、风扇、电机、电机轴、工具轴、工具附件以及传动装置,所述电机包括定子和转子,所述电机还包括安装在定子上的散热组件,所述散热组件包括安装在定子铁芯上的主体件,和设置于主体件两端的第一分支件和第二分支件,所述定子铁芯包括第一表面和第二表面,所述第一表面靠近线圈绕组,所述第二表面朝向所述散热通道,其中,所述第一分支件设置在所述定子铁芯的第一表面上,第二分支件设置在所述定子铁芯的第二表面上。本发明所公开的电动工具以及电机有效提高了其内部电机的散热效率。(The invention discloses an electric tool and a motor, wherein the electric tool comprises a shell assembly, a fan, a motor shaft, a tool accessory and a transmission device, the motor comprises a stator and a rotor, the motor also comprises a heat dissipation assembly arranged on the stator, the heat dissipation assembly comprises a main body piece arranged on a stator iron core, and a first branch piece and a second branch piece which are arranged at two ends of the main body piece, the stator iron core comprises a first surface and a second surface, the first surface is close to a coil winding, the second surface faces a heat dissipation channel, the first branch piece is arranged on the first surface of the stator iron core, and the second branch piece is arranged on the second surface of the stator iron core. The electric tool and the motor disclosed by the invention effectively improve the heat dissipation efficiency of the motor inside the electric tool and the motor.)

1. A power tool, comprising:

the motor comprises a stator, a rotor and a motor shaft, wherein the stator comprises a stator core and a coil winding, the coil winding is wound on the stator core, and the motor shaft is connected with the rotor and driven by the rotor;

a tool accessory;

a tool shaft to support the tool attachment;

a transmission coupling the motor shaft and the tool shaft;

the motor comprises a shell assembly and a motor body, wherein the shell assembly is provided with an air inlet and an air outlet and comprises a main shell for accommodating the motor and a heat dissipation channel formed between the motor and the main shell, airflow is arranged in the heat dissipation channel, and the airflow flows out of the air outlet from the air inlet of the shell assembly through the heat dissipation channel;

its characterized in that, the motor still includes radiator unit, radiator unit is including installing the main part on stator core, and set up in the first branch spare and the second branch spare at main part both ends, stator core includes first surface and second surface, the first surface is close to the coil winding, the second surface orientation heat dissipation channel, wherein, first branch spare sets up on stator core's the first surface, the second branch spare sets up on stator core's the second surface.

2. The power tool of claim 1, wherein the heat sink assembly is an integral heat sink that extends at least partially from the first surface to the second surface.

3. The power tool of claim 1, wherein the stator core includes a core base and a winding portion disposed to be connected to the core base, the winding portion being used to wind a coil winding, the core base having at least one core slot, the core slot including a first slot and a second slot, the first slot being formed at the first surface, the first leg being inserted into the core base through the first slot, the second slot being formed at the second surface such that the second leg is inserted into the core base through the second slot and is partially exposed to the heat dissipation channel.

4. The power tool according to claim 1 or 2, wherein the second branch member includes a first heat sink member and a second heat sink member, the first heat sink member is connected to the first branch member, the second heat sink member is connected to the first heat sink member, and the second heat sink member includes at least one heat sink.

5. The power tool according to claim 1 or 2, wherein the second branch member includes a first heat sink member and a second heat sink member, the first heat sink member is connected to the first branch member, the second heat sink member includes at least one tooth portion and a tooth groove, the tooth portion and the tooth groove are alternately provided on a surface of the first heat sink member, the tooth portion is convex with respect to a surface of the first heat sink member, and the tooth groove is concave with respect to a surface of the first heat sink member.

6. The power tool of claim 1 or 2, wherein the second surface is formed at a top end of the stator core, and the second branch member extends to the top end of the stator core and is partially disposed in the heat dissipation channel.

7. The power tool of claim 1, wherein a ratio of a thermal conductivity of the heat sink to a thermal conductivity of the stator core is greater than 2.7.

8. The power tool of claim 1, wherein a ratio of a width dimension of the core slot to a width dimension of the coil winding ranges from 0.14 to 0.2.

9. A motor for use with a power tool, comprising:

a rotor;

the stator comprises a stator core and a coil winding, and the coil winding is wound on the stator core;

the motor shaft is connected with the rotor, is driven by the rotor to rotate and is used for outputting power to the electric tool;

its characterized in that, the motor still includes radiator unit, radiator unit is including installing the main part on stator core, and set up in the first branch spare and the second branch spare at main part both ends, stator core includes first surface and second surface, the first surface is close to the coil winding, the second surface orientation heat dissipation channel, wherein, first branch spare sets up on stator core's the first surface, the second branch spare sets up on stator core's the second surface.

10. The motor of claim 9, wherein the stator core includes a core base and a winding portion disposed to be connected to the core base, the winding portion being used to wind a coil winding, the core base having at least one core slot including a first slot and a second slot, the first slot being formed at the first surface, the first leg being inserted into the core base through the first slot, the second slot being formed at the second surface such that the second leg is inserted into the core base through the second slot and is partially exposed to the heat dissipation channel.

11. The electric machine of claim 10, wherein the second branch member includes a first heat sink member and a second heat sink member, the first heat sink member being connected to the first branch member, the second heat sink member being connected to the first heat sink member.

Technical Field

The invention relates to an electric tool and a motor thereof.

Background

While electric tools are commonly used as auxiliary tools, they play an important role in the daily life of people, the problem of heat dissipation of the motor of the electric tool is an important factor affecting the performance of the electric tool. When the motor runs, the heat generated by the winding coil in running causes the motor structure to be heated, and when the temperature in the motor is too high, the magnetism of the magnet in the motor can be influenced, so that the motor fails, and the consequence that the electronic equipment cannot run or part of functions are damaged is caused.

Generally, a thermistor is connected in a coil winding to perform overheat protection on a motor, and the thermistor induces a high-temperature state to automatically control the power-off of the motor when the motor is overheated, so that the motor stops to protect the motor from being damaged due to overheating. In the motor that the radiating effect is not good, too high motor temperature can lead to the frequent power-off protection of thermistor to make the frequent automatic turn-off of motor, thereby be unfavorable for user to electric tool's normal use.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention mainly aims to provide an electric tool and a motor thereof so as to improve the heat dissipation efficiency.

In order to achieve the above main object, the present invention provides an electric tool, including a housing assembly, a motor shaft, a tool accessory, and a transmission device, the transmission device is used for connecting the motor shaft to the tool shaft, the tool shaft is used for supporting the tool accessory, the housing assembly includes a main housing, an air inlet, an air outlet, and a heat dissipation channel formed between the motor and the main housing, wherein the motor is accommodated in the main housing, the motor includes a stator and a rotor, wherein the stator includes a stator core and a coil winding, and the coil winding is wound around the stator core; wherein, the air current has in the heat dissipation channel, flows the air outlet via the heat dissipation channel from casing assembly's air intake, the motor still includes radiator unit, radiator unit is including installing the main part on stator core, and set up in the first branch spare and the second branch spare at main part both ends, stator core includes first surface and second surface, the first surface is close to the coil winding, the second surface orientation heat dissipation channel, wherein, first branch spare sets up on stator core's the first surface, the second branch spare sets up on stator core's the second surface.

Further, the heat dissipation assembly is an integrated heat dissipation member that extends at least partially from the first surface to the second surface.

Further, stator core includes the iron core base body and set up connect in the portion of winding of iron core base body, the portion of winding is used for winding coil winding, the iron core base body has an at least iron core fluting, the iron core fluting includes first fluting and second fluting, first fluting form in the first surface, first branch spare passes through first fluting inserts the iron core base body, the second fluting form in the second surface, make the second branch spare pass through the second fluting insert the iron core base body and part expose in heat dissipation channel.

Furthermore, the second branch member comprises a first heat dissipation part and a second heat dissipation part, the first heat dissipation part is connected to the first branch member, the second heat dissipation part is connected to the first heat dissipation part, and the second heat dissipation part comprises at least one heat dissipation fin.

Furthermore, the second branch member comprises a first heat dissipation member and a second heat dissipation member, the first heat dissipation member is connected to the first branch member, the second heat dissipation member comprises at least one tooth portion and tooth grooves, the tooth portion and the tooth grooves are arranged on the surface of the first heat dissipation member in a staggered mode, the tooth portion protrudes relative to the surface of the first heat dissipation member, and the tooth groove is recessed relative to the surface of the first heat dissipation member.

Further, the second surface is formed on the top end of the stator core, and the second branch piece extends to the top end of the stator core and is partially arranged in the heat dissipation channel.

Further, the ratio of the heat conductivity coefficient of the heat dissipation member to the heat conductivity coefficient of the stator core is greater than 2.7.

Furthermore, the ratio interval of the width dimension of the iron core slot and the width dimension of the coil winding is 0.14-0.2.

Further, the second heat dissipation part comprises at least one tooth part and tooth grooves, the tooth part and the tooth grooves are arranged on the surface of the first heat dissipation part in a staggered mode, the tooth part protrudes relative to the surface of the first heat dissipation part, and the tooth grooves are recessed relative to the surface of the first heat dissipation part.

Further, the second surface is formed on the top end of the stator core, and the second branch piece extends to the top end of the stator core and is partially arranged in the heat dissipation channel.

In order to achieve the above main object, the present invention provides a motor applied to an electric power tool, comprising: a rotor; the stator comprises a stator core and a coil winding, and the coil winding is wound on the stator core; the motor shaft is connected with the rotor, is driven by the rotor to rotate and is used for outputting power to the electric tool; the motor still includes radiator unit, radiator unit is including installing the main part piece on stator core, and set up in the first branch piece and the second branch piece at main part piece both ends, stator core includes first surface and second surface, the first surface is close to the coil winding, the second surface orientation heat dissipation channel, wherein, first branch piece sets up on stator core's the first surface, the second branch piece sets up stator core's the second is on the surface.

Further, stator core includes the iron core base body and set up connect in the portion of winding of iron core base body, the portion of winding is used for winding coil winding, the iron core base body has an at least iron core fluting, the iron core fluting includes first fluting and second fluting, first fluting form in the first surface, first branch spare passes through first fluting inserts the iron core base body, the second fluting form in the second surface, make the second branch spare pass through the second fluting insert the iron core base body and part expose in heat dissipation channel.

Furthermore, the second branch piece comprises a first heat dissipation part and a second heat dissipation part, the first heat dissipation part is connected to the first branch piece, and the second heat dissipation part is connected to the first heat dissipation part.

Advantageous effects

According to the electric tool and the motor thereof provided by the invention, the heat dissipation assembly with high heat conductivity is arranged in the motor, and the heat generated by the heat dissipation assembly is transferred to the heat dissipation channel through the heat dissipation assembly by the surface contact of the heat dissipation assembly with the coil winding and the stator core, so that the heat dissipation efficiency of the motor is improved, and the temperature rise in the electric tool and the motor is effectively reduced.

Drawings

Fig. 1 is a schematic perspective view of an electric power tool according to the present invention.

Fig. 2 is a plan view of the power tool of the present invention.

Fig. 3 is a cross-sectional view of the electric power tool of fig. 1 taken along a.

Fig. 4 is a cross-sectional view of the electric power tool of fig. 1 taken along B.

Fig. 5 is a schematic structural diagram of a motor according to a first preferred embodiment of the present invention.

Fig. 6 is a cross-sectional view of the motor according to the first preferred embodiment of the present invention.

Fig. 7 is a schematic structural view of a stator core and a heat dissipation assembly according to a first preferred embodiment of the present invention.

Fig. 8 is a schematic structural diagram of a heat dissipation assembly according to a second preferred embodiment of the invention.

Fig. 9 is a schematic structural diagram of a heat dissipation assembly according to a third preferred embodiment of the invention.

Fig. 10 is a schematic structural diagram of a heat dissipation assembly according to a fourth preferred embodiment of the invention.

Fig. 11 is another structural diagram of a heat dissipation assembly according to a fourth preferred embodiment of the invention.

Fig. 12 is a schematic structural diagram of a motor according to a fifth preferred embodiment of the present invention.

Fig. 13 is a top view of a motor in accordance with a fifth preferred embodiment of the present invention.

Fig. 14 is a schematic configuration diagram of the electric power tool of the present invention.

Fig. 15 is a schematic cross-sectional view of the power tool of the present invention.

Fig. 16 is a graph showing the temperature rise of the windings of the first set of coils during operation of the motor according to the present invention.

Fig. 17 is a second set of motor run coil winding temperature rise test chart B of the present invention.

Detailed Description

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be in a particular orientation, constructed and operated in a particular orientation, and thus the above terms are not to be construed as limiting the present invention.

The invention is described in detail below with reference to the figures and the embodiments.

Fig. 1 is a schematic perspective view of an electric tool according to the present invention, and fig. 2 is a top view of the electric tool according to the present invention. Fig. 3 is a cross-sectional view of the electric power tool of fig. 1 taken along a. The electric tool shown in fig. 1 and 2 is specifically an angle grinder, which is a kind of electric tool, referring to fig. 1 to 3, in the present invention, an electric tool is provided, the motor 2 is used for driving the electric tool 1 to operate, the electric tool 1 further includes a grass trimmer, a snow sweeper, a grass mower, an electric drill, an electric hammer, a pruner, and a chain saw, and is not limited to the kind of the electric tool 1, so the present invention also provides a structure of the motor 2, and the motor 2 can be applied to electric equipment such as a grass trimmer, a snow sweeper, a grass trimmer, an electric drill, an electric hammer, a pruner, and a chain saw.

Fig. 4 is a cross-sectional view of the electric power tool of fig. 1 taken along B. Fig. 5 is a schematic structural diagram of a motor according to a first preferred embodiment of the present invention. The motor 2 described with reference to fig. 4 and 5 includes a stator 10 and a rotor 20, and a motor shaft 60, wherein the rotor 20 is disposed in the stator 10, and a rotating magnetic field is generated by the stator 10 and acts on the rotor 20 to form a rotating torque. The motor shaft 60 is fixedly connected to the rotor 20 such that the rotor 20 rotates the motor shaft 60. The motor 2 may be a dc motor 2, an ac motor 2, a brushless motor 2, or a brush motor 2.

The stator 10 includes a stator core 11 and a coil winding 12, and the coil winding 12 is wound around the stator core 11. In order to optimize the heat dissipation performance of the stator 10, a heat dissipation assembly is disposed in the stator 10, the heat dissipation assembly includes a heat dissipation member 30, and the heat dissipation member 30 is disposed between the coil winding 12 and the stator core 11 to solve the problem that the heat dissipation of the coil winding 12 and the stator core 11 is affected due to low thermal conductivity of the stator core 11.

Referring to fig. 1 and 2, the electric power tool 1 further includes a housing of the electric power tool 1 and a heat dissipation channel 40 forming an interior of the housing of the electric power tool 1, and a high-speed airflow is generated in the heat dissipation channel 40 due to the operation of the motor 2, so as to improve heat dissipation efficiency. Under the condition that the motor 2 does not need to be sealed, the shell of the electric tool 1 is provided with the air inlet 41 and the air outlet 42, the heat dissipation channel 40 is communicated with the air outlet 42 and the air inlet 41 to allow heat dissipation airflow to circulate, and the heat dissipation part 30 is partially exposed in the heat dissipation channel 40, so that the high-flow-speed airflow in the heat dissipation channel 40 takes away heat through thermal convection, and the heat dissipation is accelerated.

It is worth mentioning that the heat dissipation channel 40 is formed outside the motor 2, and preferably takes away heat from the surface of the motor 2 through the air flow in the heat dissipation channel 40, as shown in fig. 3 and 4, the heat dissipation channel 40 is a channel formed outside the motor 2 only, the stator core is disposed in the heat dissipation channel 40, and the heat dissipation member 30 disposed on the stator transfers heat into the heat dissipation channel 40.

In the first preferred embodiment of the present invention, the heat dissipation member 30 is disposed on the stator core 11, so as to optimize the heat dissipation speed of the stator core 11, thereby effectively reducing the temperature rise of the stator 10 and the temperature rise of the motor 2.

Fig. 7 is a schematic structural view of a stator core and a heat dissipation assembly according to a first preferred embodiment of the present invention. As shown in fig. 5 to 7, the heat dissipating member 30 is a heat dissipating bracket, the heat dissipating member 30 is preferably configured as a "U" shaped bracket, and the heat dissipating bracket includes a first branch member 31, a main body portion 32 and a second branch member 33, the main body portion 32 connects the second branch member 33 and the first branch member 31, the first branch member 31 is disposed between the stator core 11 and the coil winding 12, conducts heat to the stator core 11 and the coil winding 12, transfers the heat to the second branch member 33 through the main body portion 32, and transfers the heat to the air through the second branch member 33 to dissipate the heat.

The stator core 11 includes a core base 112 and a winding portion 111 connected to the core base 112, and the winding portion 111 is used for winding the coil winding 12. The core base 112 is preferably provided as a hollow cylinder, the winding portion 111 extends inward from the inner surface of the core base 112, and the winding portion 111 is provided in plural and symmetrically distributed inside the core base 112. Specifically, the winding portion 111 includes a winding portion 114 and a protection end 113, and the protection end 113 is formed at an end of the winding portion 114 and extends from the end of the winding portion 114 to both sides, so that the width of the protection end 113 is greater than the width of the cross section of the winding portion 114, and the protection end 113 is used for intercepting and fixing the coil winding 12 and protecting the coil winding 12 when the coil winding 12 is wound on the core base 112.

In the first preferred embodiment of the present invention, the heat sink 30 is inserted and fixed to the stator core 11 to improve the heat dissipation efficiency of the stator 10. The core base 112 has at least one core slot 116, and the core slot 116 is adapted to the structure of the heat sink 30 such that the heat sink 30 is inserted into the core base 112 through the core slot 116. Specifically, the stator core 11 has a first surface 115 and a second surface 117 formed on opposite sides of the core base 112, and the winding portion 111 extends inward from the first surface 115. The core slot 116 is correspondingly disposed on the first surface 115 and the second surface 117, and preferably, the core slot 116 sinks from the first surface 115 toward the core base 112 to form a first slot 1161, and forms a second slot 1162 from the second surface 117 toward the core base 112, so that the heat sink 30 is correspondingly disposed in the core slot 116 and is in surface contact with the stator core 11 and the coil winding 12.

Specifically, the heat sink 30 is inserted into the core slot 116, such that the first branch piece 31 is inserted into the first slot 1161, the second branch piece 33 is inserted into the second slot 1162, and the main body 32 is located at the end of the core base 112, and the heat sink 30 is fixedly connected to the core slot 116 by welding or bonding. In one embodiment of the present invention, the U-shaped structure of the heat sink 30 may be clamped to the core substrate 112, or the heat sink 30 may be clamped by the slot design of the core slot 116, so that no additional connecting element is required to fix the heat sink 30, and the manufacturing process and the structure of the motor 2 are simplified.

It should be noted that, in addition to the heat dissipation bracket 30 shown in the figure, the second branch member 33 and the first branch member 31 may also be implemented in other forms such as a curve form and an irregular form, respectively, besides the strip form, and for convenience of manufacturing and installation, the first branch member 31 and the second branch member 33 are preferably selected to be strip forms. In order not to affect the normal performance of the stator, after multiple adjustment tests, it is preferable to set the ratio of the width dimension of the core slot 116 to the width dimension of the coil winding 12 to be between 0.14 and 0.2, so that the heat dissipation requirement of the coil winding 12 can be met, and the normal operation performance of the stator is not reduced. Correspondingly, the thickness of the first and second branches 31 and 32 is set to be between 0.3mm and 1mm, and the core slot 116 is correspondingly sized so that the first and second branches 31 and 32 can be fixed in the core slot.

The heat dissipation member 30 is located on the surface of the first branch member 31 of the first slot 1161 and contacts the coil winding 12, during the operation of the motor 2, the high-temperature coil winding 12 transfers heat to the first branch member 31 of the heat dissipation member 30 through heat conduction and transfers heat to the second branch member 33 through the main body portion 32, one surface of the second branch member 33 is exposed in the air, the motor 2 operates on the surface of the second surface 117 to form high-flow-rate air flow, and the high-flow-rate air takes the heat away from the second branch member 33 to achieve the purpose of rapid heat dissipation.

In order not to influence the magnetic circuit of the iron core and reduce the performance of the motor 2, the first branch piece 31 and the second branch piece 33 of the heat dissipation piece 30 are implemented as strip-shaped bodies with smaller widths, so that the volume of the heat dissipation piece 30 is far smaller than that of the stator iron core 11, the size of the corresponding iron core slot 116 is smaller, and the normal operation of the magnetic circuit generated by the stator iron core 11 is not influenced. On the premise of not affecting the performance of the stator core 11, by providing the plurality of core slots 116, the heat sink 30 may be disposed in plurality on the stator core 11 to improve the heat dissipation efficiency.

The heat dissipation member 30 is made of a material with a high thermal conductivity coefficient, such as aluminum, copper, graphene, and silica gel, preferably, the ratio of the thermal conductivity coefficient of the heat dissipation member 30 to the thermal conductivity coefficient of the stator core should be greater than 2.7, so as to ensure the heat dissipation performance of the heat dissipation member 30.

Referring to fig. 16, the first set of motor run coil winding temperature rise test chart a of the present invention is shown. Fig. 17 is a second set of motor run coil winding temperature rise test chart B of the present invention. When the first branch member 31 and the second branch member 32 are set to be 3mm wide and 0.5mm thick and aluminum is used as a material for manufacturing the heat sink 30, two sets of heat dissipation performance tests were performed on the heat dissipation motor of the present invention and the conventional motor, respectively. The first data shows that the temperature of the coil winding of the heat dissipation motor of the present invention is 51.14 c when the motor power is 1430W, and 59.52 c, compared to the temperature of the coil winding of the conventional motor, and the second data shows that the temperature of the coil winding of the heat dissipation motor is 47.05 c, the temperature of the coil winding of the conventional motor is 68.85 c, and the temperature drops are 8.38 c and 21.8 c, respectively, in comparison to the conventional motor, and that the effective temperature drops are 15.09 c and 21.18 c, 16.77 c and 23.47 c, 26.88 c and 38.43 c, 40.12 c and 63.51 c, respectively, when the motor power is 1560W, 1690W, 1820W and 1950W, respectively, so that the heat dissipation member can effectively dissipate heat from the motor.

Further, the inside air-cooled element that sets up of motor 2, preferred selection is fan 50, and the rotation through fan 50 accelerates the gas velocity in heat dissipation channel 40, and the heat of second branch piece 33 is taken away through thermal convection to high velocity of flow fluid to promote motor 2's radiating efficiency, in time discharge the heat effectively.

The coil winding includes a copper wire and an insulating layer, and generally, the insulating layer is configured as an enameled wire wrapping the copper wire to perform an insulation process on the copper wire. In the operation process of the motor, the enameled wire on the outer layer of the coil winding can be melted due to overhigh temperature generated by the motor, so that the enameled wire is damaged, a circuit is short-circuited, and the motor is damaged. Generally, a thermistor is connected in a coil winding to perform overheat protection on a motor, and the thermistor induces a high-temperature state to automatically control the power-off of the motor when the motor is overheated, so that the motor stops to protect the motor from being damaged due to overheating. In the motor that the radiating effect is not good, too high motor temperature can lead to the frequent power-off protection of thermistor to make the frequent automatic turn-off of motor, thereby be unfavorable for user to electric tool's normal use.

In traditional motor structure, at the motor operation in-process, coil winding 11 produces the heat, and stator core 12 is arrived in the heat transfer that coil winding 11 produced, through stator core 12 surface heat dissipation, because stator core 12 heat conductivity is low, can lead to the heat to pile up in coil winding 11 and stator core 12 in a large number, causes the stator to produce higher temperature rise. By providing the heat sink 30, the heat generated from the coil winding 11 can be increased in the heat dissipation rate by the heat sink 30 having high thermal conductivity, and the heat generated from the coil winding 11 and the stator core 12 is transferred to the second branch member 32 through the first branch member 31, and the heat generated from the second branch member 32 is taken away by the high flow velocity air flow exposed to the heat dissipation passage 40.

The electric tool 1 is exemplified by an angle grinder 13, and referring to fig. 1 and 2, the angle grinder 13 includes a grinding disc 131, a housing assembly 101, and a motor 2, wherein the motor 2 is fixed in the housing assembly 101, and the grinding disc 131 is driven to work by the power supplied by the motor 2. The angle grinder 13 further comprises a transmission mechanism 133 and an output shaft 134, the transmission mechanism 133 is connected with the output shaft 134 and is connected to the motor shaft 60 of the motor 2 through the transmission mechanism 133, the transmission mechanism 133 is used for reducing the speed of the motor shaft 60 of the motor 2, the transmission mechanism 133 comprises a first gear and a second gear which are meshed with each other, the gear ratios of the first gear and the second gear are different, so that the transmission mechanism 133 is reduced, or a reduction box is arranged for reducing the speed. The power tool also includes a tool attachment, which in the angle grinder 13 is a grinding disc 131.

Correspondingly, the housing assembly 101 further includes a main housing 102, the housing assembly 101 is used for installing and fixing the electric tool, and the main housing 102 is matched with the shape of the motor 2 for fixing the motor 2. The heat dissipation channel 40 is arranged in the angle grinder 13, the corresponding shell assembly 101 is provided with an air outlet 42 and an air inlet 41, and the air outlet 42 and the air inlet 41 are communicated with the heat dissipation channel 40 and used for air flow circulation in the heat dissipation channel 40. The heat dissipation channel 40 is formed inside the case assembly 101, the stator 10 is disposed in the heat dissipation channel 40, and the heat dissipation member is partially exposed in the heat dissipation channel 40. Fig. 8 is a schematic structural diagram of a heat dissipation assembly according to a second preferred embodiment of the invention. In the second preferred embodiment of the present invention, the first branch element 31A and the main body element 32A of the heat sink 30 are unchanged, and the second branch element 33A is changed from the first preferred embodiment. The second branch member 33A includes a first heat sink member 331A and a second heat sink member 332A, the first heat sink member 331A is correspondingly inlaid in the second slot 1162, the first heat sink member 331A is connected to the second heat sink member 332A for increasing the volume of the second branch member 33A, thereby partially transferring the heat of the first heat sink member 331A to the second heat sink member 332A, and increasing the surface area of the second branch member 33A, thereby increasing the heat exchange area of the second branch member 33A, and the second heat sink member 332A is rapidly cooled by high-flow-rate gas in the heat dissipation channel 40 through thermal convection.

The second heat sink portion 332A includes at least one heat sink 3321A, and the heat sink 3321A is connected and fixed to the first heat sink portion 331A. The heat sink 3321A is connected at one end to the first heat sink part 331A and extends outward from the first heat sink part 331A in an opposite direction to the stator core 11 such that the heat sink 3321A is exposed in the heat dissipation channel 40. The connection relationship between the heat sink 3321A and the first heat sink portion 331A may be through welding, clamping, or integral molding, so that the first heat sink portion 331A fixes the second heat sink portion 332A, and can transfer heat thereof to the second heat sink portion 332A, and the heat is taken away by air flow around the second heat sink portion 332A for heat dissipation.

Preferably, a gap is formed between the fins 3321A so that the surfaces of the fins 3321A do not adhere to each other, thereby increasing the effective area of heat exchange. The second first branch member 31A is also made of a high heat conduction material, such as a copper sheet, a silicon sheet, and the like, and the thickness of the heat dissipation sheet 3321A is smaller than that of the first branch member 31A, so that the load on the motor 2 is reduced.

Fig. 9 is a schematic structural diagram of a heat dissipation assembly according to a third preferred embodiment of the invention. In the third preferred embodiment of the present invention, the first branch piece 31B and the main body piece 32B of the heat sink 30 are unchanged in shape, and the second branch piece 33B is changed from the first preferred embodiment. The second branch member 33B includes a first heat sink member 331B and a second heat sink member 332B, the second heat sink member 332B is formed on the surface of the first heat sink member 331B and is exposed in the heat dissipation channel 40, the first heat sink member 331B is correspondingly embedded in the second groove 1162, the heat of the first heat sink member 331B is partially transferred to the second heat sink member 332B, and the surface area of the second branch member 33B is increased, so that the heat exchange area of the second branch member 33B is increased, and the second heat sink member 332B is rapidly cooled by high-flow-rate gas in the heat dissipation channel 40 through heat convection.

The second heat sink part 332B includes at least one tooth portion 3321B and a tooth groove 3322B, the tooth portions 3321B and the tooth grooves 3322B are alternately disposed on the surface of the first heat sink part 331B, the tooth portion 3321B protrudes relative to the surface of the first heat sink part 331B, the tooth groove 3322B is recessed relative to the surface of the first heat sink part 331B, the tooth portions 3321B and the tooth grooves 3322B may be in the form of a cylinder, a cone, a polygon, or the like, preferably, the second heat sink part 332B is integrally formed relative to the first heat sink part 331B, and is manufactured by molding, or the second heat sink 30 may be fixedly connected to the first heat sink 30 by welding or clamping.

Fig. 10 is a schematic structural diagram of a heat dissipation assembly according to a fourth preferred embodiment of the invention. In a fourth preferred embodiment of the present invention, the second surface is formed at a top end of the stator core, and the second branch extends to the top end of the stator core and is partially disposed in the heat dissipation channel.

The heat dissipation bracket includes a first branch piece 31C and a second branch piece 33C, or in other words, the main body piece is the second branch piece 33C, the second branch piece 33C is connected with the first branch piece 31C, the first branch piece 31C is disposed between the stator core 11 and the coil winding 12, conducts heat to the stator core 11 and the coil winding 12, transfers the heat to the second branch piece 33C, and transfers the heat to the air through the second branch piece 33C to dissipate the heat.

Correspondingly, the core base 112 has at least one core slot 116, and the core slot 116 is adapted to the structure of the heat sink 30, such that the heat sink 30 is inserted into the core base 112. The core slot 116 is correspondingly disposed on the first surface 115, the core slot 116 sinks from the first surface 115 toward the core base 112 to form a first slot 1161, the first branch piece 31C is fixed to the first slot 1161, the heat sink 30 is fixedly connected to the core slot 116 by welding or bonding, and the heat sink is in surface contact with the stator core 11 and the coil winding 12.

The second branch member 33C is integrally connected to the first branch member 31C, and when the first branch member 31C is inserted into the first slot 1161, the second branch member 33C is located at the side end of the stator core 11, and the second branch member 33C is exposed in the heat dissipation channel 40, so as to improve the heat dissipation efficiency. Similarly, the second branch member 33C includes a first heat sink member 331C and a second heat sink member 332C, in which the first heat sink member 331C is formed on the top end of the stator core 11, and the second heat sink member 332C is connected to the first heat sink member 331C and exposed to the heat dissipation channels 40. Correspondingly, the second surface is formed at the top end of the stator core 11, and the second branch 33C extends to the top end of the stator core 11 and is partially disposed in the heat dissipation channel 40.

Referring to fig. 10, in one embodiment, the second heat sink member 332C includes at least one tooth and a tooth socket alternately disposed on the first heat sink member surface, the tooth being convex with respect to the first heat sink member surface, and the tooth socket being concave with respect to the first heat sink member surface. The second heat sink member 332C is identical to the second preferred embodiment and will not be described in detail.

Fig. 11 is another structural diagram of a heat dissipation assembly according to a fourth preferred embodiment of the invention. Referring to fig. 11, in one embodiment, the second heat sink portion 332C includes at least one heat sink, and the heat sink is fixedly coupled to the first heat sink portion 331C. One end of the heat sink is connected to the first heat sink part 331C and extends outward from the first heat sink part 331C in a direction opposite to the stator core 11 such that the heat sink is exposed to the heat dissipation passage 40. The connection relationship between the heat dissipation plate and the first heat dissipation part 331C may be through welding, clamping, or integral molding, so that the first heat dissipation part 331C fixes the second heat dissipation part 332C. The second heat sink member 332C is identical to the third preferred embodiment and will not be described in detail.

Fig. 12 is a schematic structural diagram of a motor according to a fifth preferred embodiment of the present invention. Fig. 13 is a top view of a motor in accordance with a fifth preferred embodiment of the present invention. In the fifth preferred embodiment of the present invention, the heat sink includes a main body 32D, and a first branch 31D and a second branch 33D extending from the main body, the first branch 31D is disposed to be attached to the coil winding 12D, and the second branch 33D extends from the main body and is attached to the outer wall of the core substrate, and extends toward the heat dissipation channel, so that heat generated by the motor is transferred from the first branch 31D to the second branch 33D, and the heat dissipation is accelerated through the heat dissipation channel.

The heat sink 30D is inserted and fixed to the stator core 11D to improve the heat dissipation efficiency of the stator 10. In order to ensure the connection and fixation relationship between the heat sink 30D and the stator core 11D, the core base 112D is provided with at least one core slot 116D, and the core slot 116D is adapted to the structure of the heat sink 30D, so that the heat sink 30D is inserted into the core base 112D through the core slot 116D. Specifically, the stator core 11D has a first surface 115D and a second surface 117D formed on opposite sides of the core base 112D, and the winding portion 111 extends inward from the first surface 115D. The core slot 116D is correspondingly disposed on the second surface 117D, and the core slot 116D is formed from the second surface 117D toward the core base 112D, so that the heat sink 30D is correspondingly disposed in the core slot 116D and is in surface contact with the stator core 11D and the coil winding 12D.

After the heat sink 30D is inserted into the stator core, the first branch member 31D is fixed to the vicinity of the coil winding 12D, and the first branch member 31D is made to fit the coil winding 12D. The heat dissipation member 30D is made of a high heat conduction material, and preferably, the first branch member 31D and the second branch member 33D are selected to be strip-shaped bodies in order to reduce the influence on the running state of the motor, and the ratio of the width dimension of the iron core slot 116D to the width dimension of the coil winding 12D is set to be 0.14-0.2, so that the heat dissipation requirement of the coil winding 12D can be met, and the normal running performance of the stator cannot be reduced. Correspondingly, the thickness of the first and second branches 31D and 32D is set to be between 0.3mm and 1mm, and the core slot 116D is correspondingly sized so that the first and second branches 31D and 32D can be fixed in the core slot. So that the second branch 33D can be inserted into the core slot 116D and fixed by the core slot 116D.

After the heat sink 30D is fixed to the stator core 11D, the first branch piece 31D is correspondingly disposed near the coil winding 12D and in surface contact with the coil winding 12D. In the operation process of the motor, after the coil winding 12D generates a large amount of heat, the heat is transferred to the first branch part 31D of the heat dissipation member 30D in surface contact with the coil winding 12D, because the heat dissipation member 30D is made of a material with high thermal conductivity, the heat can be rapidly transferred from the first branch part 31D to the second branch part 33D, the second branch part 33D is exposed in the heat dissipation channel 40, and in the operation process of the electric tool, the electric tool generates high-flow-speed airflow in the heat dissipation channel 40, so that the heat in the second branch part 33D can be rapidly taken away. In particular, in the main body of the heat sink mentioned in the above embodiments, the first branch piece 31D and the second branch piece 33D may be integrally formed by molding, so that the first branch piece 31D and the second branch piece 33D in the above embodiments are integrally connected by the main body, or the first branch piece 31D, the second branch piece 33D and the main body are connected by welding, snapping, adhering, etc. to form an integral form of the heat sink.

The invention also provides an electric tool, which comprises a shell assembly 101, a motor 2, a motor shaft 60, a tool shaft, tool accessories and a transmission device 133, wherein the transmission device 133 is used for connecting the motor shaft 60 to the tool shaft which is used for supporting the tool accessories, the shell assembly comprises a main shell 102, an air inlet, an air outlet and a heat dissipation channel 40 formed between the motor 2 and the main shell 102, the motor 2 is accommodated in the main shell 102, the motor 2 comprises a stator 10 and a rotor 20, the stator 10 comprises a stator core 11 and a coil winding 12, and the coil winding 12 is wound on the stator core 11; wherein, the air current has in the heat dissipation channel 40, flows out the air outlet from the air intake of casing subassembly 101 via heat dissipation channel 40, motor 2 still includes heat dissipation subassembly, heat dissipation subassembly 30 is including installing main part 32 on stator core 11, and set up in first branch piece 31 and the second branch piece 33 at main part both ends, stator core 11 includes first surface and second surface, the first surface is close to coil winding 12, the second surface orientation heat dissipation channel 40, wherein, first branch piece 31 sets up on stator core 11's the first surface, second branch piece 33 sets up on stator core 11's the second surface. Preferably, the heat sink assembly 40 is formed by welding, clamping or bonding the first branch piece 31 and the second branch piece 33 with the main body piece 32.

Fig. 14 is a schematic configuration diagram of the electric power tool of the present invention. Fig. 15 is a cross-sectional schematic view of a power tool illustrated in the present invention. Referring to fig. 14 and 15, a schematic structural view of another power tool is shown, and the power tool shown in fig. 14 and 15 is an electric circular saw 14. The electric circular saw 14 is used for a user to perform cutting operation such as cutting wood, stone, etc., the electric circular saw 14 includes a housing assembly 101, a saw blade 142, a power source 143, and a bottom plate 144, the motor 2 is installed inside the housing assembly 101, and the housing assembly 101 includes a main housing 102 for accommodating the motor 2. The saw blade 142 rotates about an axis relative to the housing assembly 101 to cut a workpiece, the base plate 144 extends in a plane for contact with the workpiece and has a cutting slot, and the saw blade 142 passes through the cutting slot of the base plate 144 and rotates within the cutting slot.

The motor 2 includes a motor shaft 60 for outputting power, and the electric circular saw 14 further includes a transmission for linking the motor 2 and the saw blade 142, the transmission connecting the motor shaft 60 and the saw blade 142 such that the motor 2 can drive the saw blade 142 to rotate about the axis. The housing assembly 101 includes an air inlet and an air outlet, preferably such that the air inlet is disposed between the power source 143 and the motor 2, such that the air flow can flow through the motor 2 to improve the heat dissipation efficiency of the motor 2. The power tool further includes a tool attachment, which is a saw blade 142 in the electric circular saw 14.

The housing assembly 101 includes a main housing 102 for housing the motor 2, the main housing 102 forming an internal cavity for housing the motor 2. The housing assembly 101 is also formed with a gripping means 15 for gripping by a user. The holding device 15 specifically includes: a first grip 151 and a second grip 152. The first holding member 151 is used for being held by one hand of a user to operate the electric circular saw 14, an operating switch for controlling the start and stop of the electric circular saw 14 is further arranged on the first holding member 151, and the second holding member 152 is used for being held by the other hand of the user. The blade 142 cuts the workpiece as it rotates relative to the housing assembly 101 about the axis. Preferably, the power source 143 is provided as a detachable battery pack, and the battery pack is mounted in the electric circular saw 14 to supply power to the electric circular saw 14. The battery pack can be detachably coupled to the housing assembly 101 by a user to supply power to the motor 2.

The housing assembly 101 is further formed with an installation portion for detachably connecting a battery pack, the installation portion is disposed at one end of the first holding member 151, the first holding member 151 is connected with the installation portion and the main housing 102, the installation portion is also connected with the first holding member 151 and the main housing 102, thus, the first holding member 151, the main housing 102 and the installation portion are sequentially connected and surround an opening formed for a user to pass through a hand for holding the first holding portion, the opening is located on one side of the motor 2 away from the transmission device, that is, the motor 2 is disposed between the opening and the transmission device.

In order to radiate heat for the motor 2, the fan 50 is arranged on the output shaft of the motor 2, and the motor 2 drives the fan 50 to discharge air to generate radiating air flow when rotating at a high speed, so that air is blown to radiate the electric circular saw 14.

Specifically, the motor 1 is disposed in the main housing 102, the stator 10 of the motor 1 is provided with a heat sink 30 inserted into the core slot 116, such that the first branch piece 31 is inserted into the first slot 1161, the second branch piece 33 is inserted into the second slot 1162, and the main body 32 is located at an end of the core base 112, and the heat sink 30 is fixedly connected to the core slot 116 by welding or bonding.

The heat dissipation member 30 is made of a high-thermal-conductivity material, such as copper, graphene, silica gel and the like, and contacts the coil winding 12 on the surface of the first branch member 31 of the first slot 1161, when the electric circular saw 14 is in operation, the motor 2 is in operation, the high-temperature coil winding 12 transfers heat to the first branch member 31 of the heat dissipation member 30 through heat conduction, and transfers the heat to the second branch member 33 through the main body portion 32, one surface of the second branch member 33 is exposed in the air, the motor 2 is in operation on the surface of the second surface 117 to form high-flow-rate air flow, and the high-flow-rate air takes the heat of the second branch member 33 away from the heat to achieve the purpose of rapid heat.

Further, the air outlet is disposed on the main housing 102, and the air outlet is further located at an end of the motor 2 close to the transmission device, so that the heat dissipation airflow can flow through the motor 2 from the air inlet to the air outlet, and the motor 2 is efficiently dissipated. The housing assembly 101 is further formed with a gear case 145 for accommodating the transmission, and the gear case 145 is recessed with respect to the main housing 102 in a radial direction perpendicular to the axis of the motor shaft 60 so that the heat-dissipating airflow flowing out from the air outlet can flow through the outside of the gear case 145 to dissipate heat from the transmission located inside the gear case 145. In this embodiment, the gear box 145 and the main housing 102 are integrally formed, and the interior of the gear box 145 and the interior of the main housing 102 are in communication with each other, such that a portion of the heat dissipating airflow will flow through the interior of the gear box 145 and then out of the saw blade 142, thereby further dissipating heat from the transmission.

As shown in fig. 10, in order to control the motor 2 and the battery pack, the electric circular saw 14 further includes a circuit board electrically connected to the motor 2 through a wire. The circuit board is located in the main housing 102, and the circuit board is further disposed between the motor 2 and the air inlet, so that the heat dissipation airflow can sequentially flow through the circuit board and the motor 2, and further the heat dissipation airflow can also dissipate heat for the circuit board. In the embodiment, the circuit board includes a circuit substrate extending in a plane perpendicular to the axis of the motor shaft 60, and in order to match the shape of the main housing 102, the circuit substrate is substantially circular, so that the space occupied by the circuit board in the main housing 102 can be reduced, the structural arrangement inside the main housing 102 can be more compact, the size of the electric circular saw 14 in the direction of the motor shaft 60 can be reduced, the overall size of the electric circular saw 14 can be smaller, and the operation by a user can be more convenient.

In order to prevent dust generated by the cutting chips formed during the cutting process, the electric circular saw 14 of the present embodiment is further provided with an automatic dust suction structure, and the specific structure thereof is well known in the art and will not be described herein.

The heat sink 30 mentioned in the above embodiments may also be directly fixed to the stator core by welding or bonding instead of slotting the core, so that the first branch of the heat sink is attached to the winding surface of the coil, and the second branch of the heat sink is exposed in the heat dissipation channel.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.