Chain saw

Abstract

The invention provides a chain saw which comprises a main machine shell, an axial flow fan, a motor and an electronic control device, the axial flow fan, the motor and the electronic control device are all arranged in the main machine shell, and the orthographic projection of the axial flow fan on a first plane and the orthographic projection of the electronic control device on the first plane at least partially coincide or are tangent. The first plane is perpendicular to the fan axis X1 and parallel to the vertical direction H; the axial distance L1 between the axial fan and the electronic control device in the extending direction of the fan axis X1 is smaller than or equal to 50 mm, at least part of the orthographic projection of the motor on the second plane is located in the orthographic projection of the electronic control device on the second plane, and the second plane is parallel to the fan axis X1 and the vertical direction H. The axial fan, the motor and the electronic control device are reasonably arranged in the main machine shell, cooling air flow exhausted by the axial fan can flow through the motor and the electronic control device at the same time, and therefore efficient heat dissipation can be conducted on the motor and the electronic control device at the same time.

Description

[0001] This application claims priority to Chinese patent application No. 202411388341.0, filed on September 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application, and the embodiments thereof, pertain to the field of power tool technology, and particularly to a chainsaw. Background Technology

[0003] Power tools, taking chainsaws as an example, typically include a main housing, a motor housed within the main housing, electronic control devices, and working components. The motor drives the working components to perform tasks. During chainsaw operation, the motor and electronic control devices are the main heat sources. To prevent the chainsaw from stopping due to overheating, effective heat dissipation for the motor and electronic control devices within the housing is necessary. This is usually achieved by installing a cooling fan inside the main housing and providing ventilation openings on the housing itself. The motor drives the cooling fan to circulate cooling air around the motor and electronic control devices, effectively expelling heat from inside the housing. However, in related technologies, the relative positions of the cooling fan, motor, and electronic control devices within the main housing are often not optimally arranged, resulting in inadequate heat dissipation. Summary of the Invention

[0004] The purpose of this disclosure is to provide a chainsaw that addresses the problem of how to better cool the motor and electronic control device, thereby improving the heat dissipation effect of the motor and electronic control device.

[0005] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0006] A chainsaw extends along three orthogonal spatial directions: front-back (L), left-right (W), and up-down (H), the chainsaw comprising:

[0007] The main unit housing extends along the front-to-back direction L, and the main unit housing is provided with an air inlet and an air outlet that communicate with the outside.

[0008] Guide plate, installed to the main unit housing;

[0009] Chain, mounted on the guide plate;

[0010] A gripping component is provided on the main unit housing;

[0011] A fan, located inside the main unit housing, draws cooling air from the air inlet into the interior of the main unit housing;

[0012] A motor is installed inside the main unit housing, and the motor is connected to the fan drive.

[0013] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0014] The fan is configured as an axial fan, which is capable of rotating about the fan axis X1. The orthographic projection of the axial fan on a first plane is at least partially coincident with or tangent to the orthographic projection of the electronic control device on the first plane. The first plane is a plane perpendicular to the fan axis X1 and parallel to the vertical direction H. In the extension direction of the fan axis X1, the axial distance L1 between the axial fan and the electronic control device is configured to be less than or equal to 50 mm.

[0015] In one embodiment, the two axial sides of the axial fan are defined as the inlet side S1 and the outlet side S2, respectively. The motor and the electronic control device are located at the outlet side S2 of the axial fan. The orthographic projection of the motor on a second plane is at least partially located within the orthographic projection of the electronic control device on the second plane. The second plane is a plane that is parallel to both the fan axis X1 and the vertical direction H.

[0016] In one embodiment, the axial distance L1 between the axial fan and the electronic control device is configured to be 2mm to 50mm in the extending direction of the fan axis X1.

[0017] In one embodiment, the motor has a motor housing extending in the direction of the motor output shaft, and the orthographic projection of the axial fan on the first plane covers the orthographic projection of the motor housing on the first plane.

[0018] In one embodiment, the ratio of the diameter D1 of the orthographic projection of the axial fan onto the first plane to the outer diameter D2 of the orthographic projection of the motor housing onto the first plane is configured to be 1 to 3.

[0019] In one embodiment, the shortest distance from the electronic control device to the fan axis X1 is configured to be greater than the radius R2 of the motor housing, and the ratio of the shortest distance from the electronic control device to the fan axis X1 to the radius R2 of the motor housing is configured to be 1.05 to 3.

[0020] In one embodiment, the motor includes a motor housing extending in the direction of the motor output shaft, and the electronic control device includes a heat dissipation surface disposed opposite to the motor housing in the front-rear direction L, wherein the shortest distance L2 from the heat dissipation surface to the fan axis X1 is configured to be 33mm to 43.5mm.

[0021] In one embodiment, the motor includes a motor housing extending in the direction of the motor output shaft, the electronic control device includes a heat dissipation surface disposed opposite to the motor housing in the front-rear direction L, the orthographic projection of the fan axis X1 on the first plane is a projection point U, the orthographic projection of the heat dissipation surface on the first plane is a projection line Q, and a perpendicular line segment V is drawn from the projection point U to the projection line Q, the length L2 of the perpendicular line segment V is configured to be 33mm to 43.5mm.

[0022] In one embodiment, the motor has a motor housing extending in the direction of the motor output shaft. The motor housing has a first cross-section that is tangent only to the surface of the motor housing. The first cross-section is parallel to the heat dissipation surface, and the shortest distance L3 between the two is configured to be 1mm to 40mm.

[0023] In one embodiment, the axial sides of the axial fan are respectively the air inlet side S1 and the air outlet side S2. The electronic control device is disposed on the air outlet side S2 of the axial fan. The surface of the electronic control device near the motor constitutes a heat dissipation surface. The heat dissipation surface is parallel to the fan axis X1. The orthographic projection of the motor on the second plane is at least partially located within the orthographic projection of the heat dissipation surface on the second plane.

[0024] In one embodiment, the electronic control device includes a base and a MOSFET. The MOSFET is disposed in the base. The heat dissipation surface is provided on the side of the base opposite to the motor housing in the front-rear direction L. The orthographic projection of the motor housing on the second plane and the orthographic projection of the heat dissipation surface on the second plane have at least a partial overlap area. The orthographic projection of the MOSFET on the second plane is at least partially located within the overlap area.

[0025] In one embodiment, the electronic control device includes a base and a MOSFET. The MOSFET is disposed in the base. The heat dissipation surface is provided on the side of the base opposite to the motor housing in the front-rear direction L. The area where the orthographic projection of the motor housing on the plane of the heat dissipation surface coincides with the heat dissipation surface is a high-speed airflow region. The orthographic projection of the MOSFET on the heat dissipation surface is at least partially located in the high-speed airflow region.

[0026] In one embodiment, the shortest distance L6 from the MOS transistor to the fan axis X1 is configured to be 33mm to 44mm.

[0027] In one embodiment, the orthographic projection of the fan axis X1 onto the first plane is a projection point U, the orthographic projection of the MOS transistor onto the first plane is a projection line M, and a perpendicular line segment Z is drawn from the projection point U to the projection line M, wherein the length L6 of the perpendicular line segment Z is configured to be 33mm to 44mm.

[0028] In one embodiment, the axial spacing L4 between the MOS transistor and the axial fan is configured to be 10 mm to 80 mm in the extending direction of the fan axis X1.

[0029] In one embodiment, the angle β between the connecting line A1 from any position on the MOS transistor to the center of the axial end face of the axial fan located on the air outlet side S2 and the fan axis X1 is configured to be 10° to 60°.

[0030] In one embodiment, the motor has a motor housing extending in the direction of the motor output shaft. The motor housing includes a front end portion located near the axial fan and a rear end portion opposite to the front end portion. In the extension direction of the fan axis X1, the axial distance L5 between the front end portion of the motor housing and the axial fan is configured to be 0.5 mm to 6 mm.

[0031] In one embodiment, the area between the front end of the motor housing and the axial fan forms a low-pressure airflow zone. The front end of the motor housing is provided with an airflow outlet communicating with the low-pressure airflow zone, and the rear end of the motor housing is provided with an airflow inlet communicating with the internal space of the main unit housing. After the cooling air flowing out from the air outlet side S2 of the axial fan flows over the surface of the motor housing, at least a portion of the cooling air enters the interior of the motor housing from the airflow inlet and flows out from the airflow outlet into the low-pressure airflow zone.

[0032] In one embodiment, the main unit housing includes a first side and a second side disposed opposite to each other in the left-right direction W, the first side or the second side is provided with the air inlet, and the axial fan is disposed opposite to the air inlet.

[0033] In one embodiment, the orthographic projection of the axial fan onto the first plane is at least partially located within the orthographic projection of the air inlet onto the first plane.

[0034] In one embodiment, the two axial sides of the axial fan are defined as the air inlet side S1 and the air outlet side S2, respectively, with the air inlet side S1 of the axial fan located close to the air inlet.

[0035] In one embodiment, the main unit housing is further provided with a flow guide shroud, the inside of which is formed a flow guide cavity communicating with the inside of the main unit housing. The flow guide shroud has an air inlet, and the flow guide cavity communicates with the outside through the air inlet. The shape of the flow guide cavity is adapted to the shape of the axial fan, and the axial fan is at least partially placed in the flow guide cavity. The shortest distance between the inner sidewall of the flow guide cavity and the fan axis X1 is configured to be 42.8mm to 52.5mm.

[0036] In one embodiment, the shortest distance from the inner wall of the flow guide cavity to the edge of the axial fan blade is configured to be 0.3 mm to 10 mm.

[0037] The purpose of this disclosure is to provide a chainsaw that addresses the issues of how to better cool the motor and electronic control unit, further preventing dust and debris from adhering and accumulating on the motor and electronic control unit, while also making the chainsaw structure more compact.

[0038] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0039] A chainsaw extends along three orthogonal spatial directions: front-back (L), left-right (W), and up-down (H), the chainsaw comprising:

[0040] The main unit housing extends along the front-to-back direction L, and the main unit housing is provided with an air inlet and an air outlet that communicate with the outside.

[0041] Guide plate, installed to the main unit housing;

[0042] Chain, mounted on the guide plate;

[0043] A gripping component is provided on the main unit housing;

[0044] A fan, installed inside the main unit housing, draws cooling air in from the air inlet into the interior of the main unit housing and discharges it to the exterior of the main unit housing from the air outlet;

[0045] A motor is disposed inside the main unit housing, the motor is connected to the fan drive, and the motor has a motor housing extending in the direction of the motor output shaft;

[0046] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0047] The fan is configured as an axial fan, which can rotate around the fan axis X1. The cooling air flow path from the axial fan to the air outlet is defined as the air outlet path. The electronic control device is disposed on the air outlet path of the cooling air. The electronic control device includes a heat dissipation surface disposed opposite to the motor housing in the front-rear direction L. The heat dissipation surface extends approximately along the heat dissipation plane. The heat dissipation plane is inclined relative to the first reference plane. The first reference plane is a plane parallel to both the fan axis X1 and the front-rear direction L. The orthographic projection of the axial fan on the first plane is a projection circle. The projection circle includes an upper semicircle and a lower semicircle in the vertical direction H. The orthographic projection of the heat dissipation surface on the first plane includes the uppermost point and the lowermost point in the vertical direction H. Tangents are drawn from the uppermost point and the lowermost point to the lower semicircle of the projection circle. The included angle ∑ formed between the two tangents and the heat dissipation surface is configured to be greater than or equal to 15°. The first plane is a plane perpendicular to the fan axis X1 and parallel to the vertical direction H.

[0048] In one embodiment, the ratio of the shortest distance from the electronic control device to the fan axis X1 to the radius R1 of the projection circle is configured to be greater than 1 and less than or equal to 2.5.

[0049] In one embodiment, the orthographic projection of the electronic control device onto the first reference plane at least partially overlaps with the orthographic projection of the motor onto the first reference plane.

[0050] In one embodiment, the heat dissipation plane of the heat dissipation surface is configured to be inclined relative to the bottom plane of the host housing, and the inclination angle α is configured to be greater than 90° and less than or equal to 150°.

[0051] In one embodiment, the tilt angle α of the heat dissipation plane of the heat dissipation surface relative to the first reference surface is configured to be greater than 90° and less than or equal to 150°.

[0052] In one embodiment, the heat dissipation surface is provided with a plurality of spaced heat dissipation ribs protruding toward the motor, and two adjacent heat dissipation ribs form a heat dissipation groove, the extension direction of the heat dissipation groove being perpendicular to the fan axis X1.

[0053] In one embodiment, a chip removal port communicating with the outside is provided on the bottom of the host housing, and the orthographic projection of the heat dissipation surface on the first reference surface and the orthographic projection of the chip removal port on the first reference surface at least partially coincide or are tangent to each other.

[0054] In one embodiment, the orthographic projection of the electronic control device on the bottom plane of the main housing extends along the front-rear direction L to form a first orthographic projection surface, and the orthographic projection of the chip discharge port on the bottom plane of the main housing at least partially coincides with or is tangent to the first projection surface.

[0055] In one embodiment, the bottom of the main housing has a chip discharge port that communicates with the outside, and the orthographic projection of the motor housing on the first reference plane at least partially coincides with the orthographic projection of the chip discharge port on the first reference plane.

[0056] In one embodiment, the air outlet is provided on the bottom of the main housing, and at least part of the chip discharge port constitutes the air outlet.

[0057] In one embodiment, the air inlet cover is provided with a filter screen.

[0058] In one embodiment, the total air inlet area of ​​the filter is greater than or equal to 600 mm². 2 And less than or equal to 2000mm 2 .

[0059] The purpose of this disclosure is to provide a chainsaw that addresses the problem of how to better cool the motor and electronic control unit.

[0060] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0061] A power tool extending along three orthogonal spatial directions: front-back (L), left-right (W), and up-down (H), the power tool comprising:

[0062] The main unit housing has an air inlet and an air outlet that communicate with the outside.

[0063] A fan, located inside the main unit housing, draws cooling air from the air inlet into the interior of the main unit housing;

[0064] A motor is disposed inside the main unit housing, the motor is connected to the fan drive, and the motor has a motor housing extending in the direction of the motor output shaft;

[0065] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0066] The fan is configured as an axial fan, which is capable of rotating around the fan axis X1. The two sides of the axial direction of the axial fan are defined as the air inlet side and the air outlet side, respectively.

[0067] The motor and the electronic control device are disposed at the air outlet side of the axial fan. The electronic control device includes a heat dissipation surface disposed opposite to the motor housing in the front-rear direction L. An airflow channel is formed between the heat dissipation surface and the motor housing. Cooling air flowing out from the air outlet side of the axial fan flows through the airflow channel. The cooling air flows through the surface of the motor housing and at least part of the heat dissipation surface at the same time.

[0068] In one embodiment, the orthographic projection of the axial fan on a first plane at least partially coincides with or is tangent to the orthographic projection of the electronic control device on a first plane, the first plane being a plane perpendicular to the fan axis X1 and parallel to the vertical direction H; and the axial distance L1 between the axial fan and the electronic control device is configured to be 2mm to 50mm in the extending direction of the fan axis X1.

[0069] In one embodiment, the orthographic projection of the motor on the second plane is at least partially located within the orthographic projection of the electronic control device on the second plane, which is a plane parallel to both the fan axis X1 and the vertical direction H.

[0070] In one embodiment, the orthographic projection of the axial fan onto the first plane overlaps the orthographic projection of the motor housing onto the first plane.

[0071] In one embodiment, the ratio of the diameter D1 of the orthographic projection of the axial fan onto the first plane to the outer diameter D2 of the orthographic projection of the motor housing onto the first plane is configured to be 1 to 3.

[0072] In one embodiment, the shortest distance from the electronic control device to the fan axis X1 is configured to be greater than the radius R2 of the motor housing, and the ratio of the shortest distance from the electronic control device to the fan axis X1 to the radius R2 of the motor housing is configured to be 1.05 to 3.

[0073] In one embodiment, the shortest distance L2 from the heat dissipation surface to the fan axis X1 is configured to be 33mm to 43.5mm.

[0074] In one embodiment, the orthographic projection of the fan axis X1 onto the first plane is a projection point U, the orthographic projection of the heat dissipation surface onto the first plane is a projection line Q, and a perpendicular line segment V is drawn from the projection point U to the projection line Q, the length L2 of the perpendicular line segment V being configured to be 33mm to 43.5mm.

[0075] In one embodiment, the motor housing has a first cut surface that is tangent only to the surface of the motor housing. The first cut surface is parallel to the heat dissipation surface and the shortest distance L3 between them is configured to be 1mm to 40mm.

[0076] In one embodiment, the heat dissipation surface is parallel to the fan axis X1, and the orthographic projection of the motor on the second plane is at least partially located within the orthographic projection of the heat dissipation surface on the second plane.

[0077] In one embodiment, the electronic control device includes a base and a MOSFET. The MOSFET is disposed in the base. The heat dissipation surface is provided on the side of the base opposite to the motor housing in the front-rear direction L. The orthographic projection of the motor housing on the second plane and the orthographic projection of the heat dissipation surface on the second plane have at least a partial overlap area. The orthographic projection of the MOSFET on the second plane is at least partially located within the overlap area.

[0078] In one embodiment, the electronic control device includes a base and a MOSFET. The MOSFET is disposed in the base. The heat dissipation surface is provided on the side of the base opposite to the motor housing in the front-rear direction L. The area where the orthographic projection of the motor housing on the plane of the heat dissipation surface coincides with the heat dissipation surface is a high-speed airflow region. The orthographic projection of the MOSFET on the heat dissipation surface is at least partially located in the high-speed airflow region.

[0079] In one embodiment, the shortest distance L6 from the MOS transistor to the fan axis X1 is configured to be 33mm to 44mm.

[0080] In one embodiment, the orthographic projection of the fan axis X1 onto the first plane is a projection point U, the orthographic projection of the MOS transistor onto the first plane is a projection line M, and a perpendicular line segment Z is drawn from the projection point U to the projection line M, wherein the length L6 of the perpendicular line segment Z is configured to be 33mm to 44mm.

[0081] In one embodiment, the axial spacing L4 between the MOS transistor and the axial fan is configured to be 10 mm to 80 mm in the extending direction of the fan axis X1.

[0082] In one embodiment, the angle β between the connecting line A1 from any position on the MOS transistor to the center of the axial end face of the axial fan located on the air outlet side S2 and the fan axis X1 is configured to be 10° to 60°.

[0083] In one embodiment, the motor housing includes a front end portion located near the axial fan and a rear end portion opposite to the front end portion, and the axial distance L5 between the front end portion of the motor housing and the axial fan is configured to be 0.5 mm to 6 mm in the extension direction of the fan axis X1.

[0084] In one embodiment, the area between the front end of the motor housing and the axial fan forms a low-pressure airflow zone. The front end of the motor housing is provided with an airflow outlet communicating with the low-pressure airflow zone, and the rear end of the motor housing is provided with an airflow inlet communicating with the internal space of the main unit housing. After the cooling air flowing out from the air outlet side S2 of the axial fan flows over the surface of the motor housing, at least a portion of the cooling air enters the interior of the motor housing from the airflow inlet and flows out from the airflow outlet into the low-pressure airflow zone.

[0085] In one embodiment, the main unit housing includes a first side and a second side disposed opposite to each other in the left-right direction W, the first side or the second side is provided with the air inlet, and the axial fan is disposed opposite to the air inlet.

[0086] In one embodiment, the orthographic projection of the axial fan onto the first plane is at least partially located within the orthographic projection of the air inlet onto the first plane.

[0087] In one embodiment, the air intake side S1 of the axial fan is located close to the air inlet.

[0088] In one embodiment, the main unit housing is further provided with a flow guide shroud, the inside of which is formed a flow guide cavity communicating with the inside of the main unit housing. The flow guide shroud has an air inlet, and the flow guide cavity communicates with the outside through the air inlet. The shape of the flow guide cavity is adapted to the shape of the axial fan, and the axial fan is at least partially placed in the flow guide cavity. The shortest distance between the inner sidewall of the flow guide cavity and the fan axis X1 is configured to be 42.8mm to 52.5mm.

[0089] In one embodiment, the shortest distance from the inner wall of the flow guide cavity to the edge of the axial fan blade is configured to be 0.3 mm to 10 mm.

[0090] In one embodiment, the heat dissipation surface extends approximately along the heat dissipation plane, which is inclined relative to a first reference plane. The first reference plane is a plane parallel to both the fan axis X1 and the longitudinal direction L. The orthographic projection of the axial fan onto the first plane is a projection circle, which includes an upper and lower semicircle in the vertical direction H. The orthographic projection of the heat dissipation surface onto the first plane includes the uppermost and lowermost endpoints in the vertical direction H. Tangents are drawn from the uppermost and lowermost endpoints to the lower semicircle of the projection circle. The included angle ∑ formed between the two tangents relative to the heat dissipation surface is configured to be greater than or equal to 15°. The first plane is a plane perpendicular to the fan axis X1 and parallel to the vertical direction H.

[0091] In one embodiment, the ratio of the shortest distance from the electronic control device to the fan axis X1 to the radius R1 of the projection circle is configured to be greater than 1 and less than or equal to 2.5.

[0092] In one embodiment, the orthographic projection of the electronic control device onto the first reference plane at least partially overlaps with the orthographic projection of the motor onto the first reference plane.

[0093] In one embodiment, the heat dissipation plane of the heat dissipation surface is configured to be inclined relative to the bottom plane of the host housing, and the inclination angle α is configured to be greater than 90° and less than or equal to 150°.

[0094] In one embodiment, the tilt angle α of the heat dissipation plane of the heat dissipation surface relative to the first reference surface is configured to be greater than 90° and less than or equal to 150°.

[0095] In one embodiment, the heat dissipation surface is provided with a plurality of spaced heat dissipation ribs protruding toward the motor, and two adjacent heat dissipation ribs form a heat dissipation groove, the extension direction of the heat dissipation groove being perpendicular to the fan axis X1.

[0096] In one embodiment, a chip removal port communicating with the outside is provided on the bottom of the host housing, and the orthographic projection of the heat dissipation surface on the first reference surface and the orthographic projection of the chip removal port on the first reference surface at least partially coincide or are tangent to each other.

[0097] In one embodiment, the orthographic projection of the electronic control device on the bottom plane of the main housing extends along the front-rear direction L to form a first orthographic projection surface, and the orthographic projection of the chip discharge port on the bottom plane of the main housing at least partially coincides with or is tangent to the first projection surface.

[0098] In one embodiment, the bottom of the main housing has a chip discharge port that communicates with the outside, and the orthographic projection of the motor housing on the first reference plane at least partially coincides with the orthographic projection of the chip discharge port on the first reference plane.

[0099] In one embodiment, the air outlet is provided on the bottom of the main housing, and at least part of the chip discharge port constitutes the air outlet.

[0100] In one embodiment, the air inlet cover is provided with a filter screen.

[0101] In one embodiment, the total air inlet area of ​​the filter is greater than or equal to 600 mm². 2 And less than or equal to 2000mm 2 .

[0102] The purpose of this disclosure is to provide a power tool that addresses the problem of how to better cool the motor and electronic control device, thereby improving the heat dissipation effect of the motor and electronic control device.

[0103] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0104] A power tool, comprising,

[0105] The main unit housing has an air inlet and an air outlet that communicate with the outside.

[0106] An axial fan is installed inside the main unit housing. The axial fan can rotate around the fan axis to draw cooling air from the air inlet into the interior of the main unit housing and exhaust it from the air outlet to the exterior of the main unit housing.

[0107] A motor is disposed inside the main unit housing, and the motor is connected to the axial flow fan drive.

[0108] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0109] The orthographic projection of the axial fan on the first plane overlaps the orthographic projection of the motor on the first plane. The orthographic projection of the axial fan on the first plane at least partially coincides with or is tangent to the orthographic projection of the electronic control device on the first plane. The first plane is perpendicular to the fan axis. The orthographic projection of the motor on the second plane is at least partially located within the orthographic projection of the electronic control device on the second plane. The second plane is parallel to the fan axis and perpendicular to the bottom plane of the main unit housing.

[0110] In one embodiment, the motor has a motor housing extending in the direction of the motor output shaft, and the orthographic projection of the axial fan on the first plane covers the orthographic projection of the motor housing on the first plane.

[0111] In one embodiment, the vertical distance from the electronic control device to the fan axis is set to be greater than the radius of the motor housing, and the ratio between the two is in the range of 1.05 to 3.

[0112] In one embodiment, the axial sides of the axial fan are the air inlet side and the air outlet side, respectively. The electronic control device is disposed on the air outlet side of the axial fan. The surface of the electronic control device near the motor constitutes a heat dissipation surface. The heat dissipation surface is parallel to the fan axis. The orthographic projection of the motor on the second plane is at least partially located within the orthographic projection of the heat dissipation surface on the second plane.

[0113] In one embodiment, the vertical distance from the heat dissipation surface to the fan axis is 33mm to 43.5mm.

[0114] In one embodiment, the motor has a motor housing extending in the direction of the motor output shaft. The motor housing has a first cross-section that is tangent only to the surface of the motor housing. The first cross-section is parallel to the heat dissipation surface and the vertical distance between the two is 1mm to 40mm.

[0115] In one embodiment, in the direction of extension of the fan axis, the axial distance from the side of the electronic control device near the axial fan to the axial fan is 2mm to 50mm.

[0116] In one embodiment, the electronic control device includes a base portion and a MOS transistor disposed within the base portion. The vertical distance from the MOS transistor to the fan axis is 33mm to 44mm, and the axial distance between the MOS transistor and the axial fan in the extending direction of the fan axis is 10mm to 80mm.

[0117] In one embodiment, the angle β between the connecting line from any position on the MOS transistor to the center of the axial end face of the axial fan on the air outlet side and the fan axis is 10° to 60°.

[0118] In one embodiment, the electronic control device includes a base portion and a MOS transistor disposed within the base portion. The surface of the base portion near the motor constitutes the heat dissipation surface. The region where the orthographic projection of the motor onto the plane of the heat dissipation surface coincides with the heat dissipation surface is a high-speed airflow region. The orthographic projection of the MOS transistor onto the heat dissipation surface is located within the high-speed airflow region.

[0119] In one embodiment, the main unit housing has two longitudinal sides extending along the longitudinal direction, wherein the air inlet is provided on either of the longitudinal sides, the axial fan is disposed opposite to the air inlet, and the air intake side of the axial fan is disposed close to the air inlet.

[0120] In one embodiment, the main unit housing is further provided with a flow guide shroud, the inside of which is formed a flow guide cavity communicating with the inside of the main unit housing. The flow guide shroud has an air inlet, and the flow guide cavity communicates with the outside through the air inlet. The shape of the flow guide cavity is adapted to the shape of the axial fan, and the axial fan is at least partially placed in the flow guide cavity. The vertical distance between the inner sidewall of the flow guide cavity and the fan axis is 42.8 mm to 52.5 mm.

[0121] In one embodiment, the vertical distance from the inner wall of the flow guide cavity to the edge of the axial fan blade is 0.3 mm to 10 mm.

[0122] In one embodiment, the power tool is a chainsaw, which further includes a cutting component, a transmission component, and a battery pack component. The cutting component and the battery pack component are respectively disposed at both ends of the main housing along the longitudinal direction of the main housing. The transmission component is disposed inside the main housing. The cutting component extends into the main housing and is driven by the motor through the transmission component. The ratio of the diameter of the axial fan to the outer diameter of the motor is in the range of 1 to 3.

[0123] The purpose of this disclosure is to provide a power tool that addresses the problem of how to better cool the motor and electronic control device, thereby improving the heat dissipation effect of the motor and electronic control device.

[0124] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0125] A power tool, comprising,

[0126] The main unit housing has an air inlet and an air outlet that communicate with the outside world.

[0127] An axial fan is installed inside the main unit housing. The axial fan can rotate around the fan axis, drawing cooling air from the air inlet into the interior of the main unit housing and discharging it from the air outlet to the exterior of the main unit housing. The two axial sides of the axial fan are defined as the air inlet side and the air outlet side, respectively.

[0128] An electric motor is disposed inside the main unit housing. The electric motor is driven and connected to the axial flow fan. The electric motor has a motor housing extending in the direction of the motor output shaft.

[0129] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0130] The motor and the electronic control device are disposed on the air outlet side of the axial fan and are close to each other. The electronic control device includes a heat dissipation surface disposed opposite to the motor housing. An airflow channel is formed between the heat dissipation surface and the motor housing. Cooling air flowing out from the air outlet side of the axial fan flows through the airflow channel. The cooling air flows through the surface of the motor housing and at least part of the heat dissipation surface at the same time, so as to dissipate heat from the motor and the electronic control device simultaneously.

[0131] In one embodiment, the vertical distance from the electronic control device to the fan axis is set to be greater than the radius of the motor housing, and the ratio between the two is in the range of 1.05 to 3.

[0132] In one embodiment, the heat dissipation surface is parallel to the fan axis, and the vertical distance from the heat dissipation surface to the fan axis is 33mm to 43.5mm.

[0133] In one embodiment, the motor housing has a first cut surface that is tangent only to the surface of the motor housing. The first cut surface is parallel to the heat dissipation surface and the vertical distance between the two is 1mm to 40mm.

[0134] In one embodiment, in the direction of extension of the fan axis, the axial distance from the side of the electronic control device near the axial fan to the axial fan is 2mm to 50mm.

[0135] In one embodiment, the electronic control device includes a base portion and a MOS transistor disposed within the base portion. The vertical distance from the MOS transistor to the fan axis is 33mm to 44mm, and the axial distance between the MOS transistor and the axial fan in the extending direction of the fan axis is 10mm to 80mm.

[0136] In one embodiment, the angle β between the connecting line from any position on the MOS transistor to the center of the axial end face of the axial fan on the exhaust side and the fan axis is 10° to 60°.

[0137] In one embodiment, the electronic control device includes a base portion and a MOS transistor disposed within the base portion. The surface of the base portion near the motor constitutes the heat dissipation surface. The region where the orthographic projection of the motor onto the plane of the heat dissipation surface coincides with the heat dissipation surface is a high-speed airflow region. The orthographic projection of the MOS transistor onto the heat dissipation surface is located within the high-speed airflow region.

[0138] In one embodiment, the main unit housing has two longitudinal sides extending along the longitudinal direction, wherein the air inlet is provided on either of the longitudinal sides, the axial fan is disposed opposite to the air inlet, and the air intake side of the axial fan is disposed close to the air inlet.

[0139] In one embodiment, the main unit housing is further provided with a flow guide shroud, the inside of which is formed a flow guide cavity communicating with the inside of the main unit housing. The flow guide shroud has an air inlet, and the flow guide cavity communicates with the outside through the air inlet. The shape of the flow guide cavity is adapted to the shape of the axial fan, and the axial fan is at least partially placed in the flow guide cavity. The vertical distance between the inner sidewall of the flow guide cavity and the fan axis is 42.8 mm to 52.5 mm.

[0140] In one embodiment, the vertical distance from the inner wall of the flow guide cavity to the edge of the axial fan blade is 0.3 mm to 10 mm.

[0141] In one embodiment, the power tool is a chainsaw, which further includes a cutting component, a transmission component, and a battery pack component. The cutting component and the battery pack component are respectively disposed at both ends of the main housing along the longitudinal direction of the main housing. The transmission component is disposed inside the main housing. The cutting component extends into the main housing and is driven by the motor through the transmission component. The ratio of the diameter of the axial fan to the outer diameter of the motor is in the range of 1 to 3.

[0142] The purpose of this disclosure is to provide a power tool that addresses the problem of how to prevent dust and debris from adhering and accumulating on the motor and electronic control device.

[0143] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0144] A power tool, comprising,

[0145] The main unit housing has an air inlet and an air outlet that communicate with the outside.

[0146] An axial fan is disposed inside the main unit housing. The axial fan is rotatable around the fan axis and has a rotation plane perpendicular to the fan axis. It draws cooling air into the interior of the main unit housing from the air inlet and discharges it to the exterior of the main unit housing from the air outlet. The path of the cooling air flowing from the axial fan to the air outlet is defined as the air outlet path.

[0147] A motor is disposed inside the main unit housing, and the motor is connected to the axial flow fan drive.

[0148] An electronic control device is installed inside the main unit housing and is electrically connected to the motor to control the operation of the motor;

[0149] The electronic control device and the motor are arranged along the longitudinal direction of the main housing. The electronic control device is located on the air outlet path of the cooling air and close to the axial fan. The electronic control device is perpendicular or inclined to the bottom plane of the main housing. The bottom plane is parallel to the longitudinal direction of the main housing and perpendicular to the rotation plane of the axial fan.

[0150] In one embodiment, the electronic control device is configured to be tilted relative to the bottom plane of the main housing at an angle greater than 90° and less than or equal to 150°.

[0151] In one embodiment, the surface of the electronic control device near the motor constitutes a heat dissipation surface, which is parallel to the fan axis of the axial fan and perpendicular or inclined to the bottom plane of the main housing.

[0152] In one embodiment, the heat dissipation surface is configured to be inclined relative to the bottom plane of the host housing at an angle greater than 90° and less than or equal to 150°.

[0153] In one embodiment, a plurality of heat dissipation ribs are protruding from the heat dissipation surface, and the opposite sides of two adjacent heat dissipation ribs and the space enclosed by the heat dissipation surface form a heat dissipation groove. The heat dissipation groove extends along the longitudinal direction of a first straight line, which is perpendicular or inclined to the bottom plane of the host housing.

[0154] In one embodiment, the first straight line is inclined relative to the bottom plane of the main unit housing at an angle greater than 90° and less than or equal to 150°.

[0155] In one embodiment, a chip discharge port communicating with the outside is provided on the bottom of the main housing, and the orthographic projection of the electronic control device on the bottom plane of the main housing is tangent to or partially intersects with the orthographic projection of the chip discharge port on the bottom plane of the main housing.

[0156] In one embodiment, the orthographic projection of the electronic control device on the bottom plane of the main housing extends along the longitudinal direction of the main housing to form a first orthographic projection surface, and the orthographic projection of the chip discharge port on the bottom plane of the main housing intersects at least partially with the first projection surface.

[0157] In one embodiment, the air outlet is provided on the bottom of the main housing, and at least part of the chip discharge port constitutes the air outlet.

[0158] In one embodiment, the axial distance between the motor and the axial fan is 0.5 mm to 6 mm in the extending direction of the fan axis.

[0159] In one embodiment, the air inlet cover is provided with a filter screen.

[0160] In one embodiment, the total air inlet area of ​​the filter is greater than or equal to 600 mm². 2 And less than or equal to 2000mm 2 .

[0161] In one embodiment, the power tool is a chainsaw, which further includes a cutting component, a transmission component, and a battery pack component. The cutting component and the battery pack component are respectively disposed at both ends of the main housing along the longitudinal direction of the main housing. The transmission component is disposed inside the main housing. The cutting component extends into the main housing and is driven by the motor through the transmission component. The ratio of the diameter of the axial fan to the outer diameter of the motor is in the range of 1 to 3.

[0162] Compared with the prior art, in the preferred embodiment of this application, the motor, electronic control device, and axial fan are rationally arranged inside the main unit housing. This allows the cooling air blown by the axial fan to simultaneously cool both the motor and the electronic control device, while also making the internal structure of the main unit housing more compact and the overall size smaller. The air inlet side of the axial fan is positioned opposite and close to the air inlet of the main unit housing, effectively reducing airflow loss along the air intake path between the air inlet and the air inlet side of the axial fan. This improves the air intake efficiency of the axial fan, ensuring that it can deliver sufficient cooling air to the motor and electronic control device, thereby guaranteeing their heat dissipation.

[0163] Meanwhile, the electronic control unit is configured to be tilted relative to the bottom plane of the main unit housing. When the axial fan continuously delivers sufficient cooling air to the motor and the electronic control unit, even if the debris and dust attached to the cooling air adhere to the surface of the electronic control unit, they will slide off the surface of the electronic control unit under the combined action of gravity and wind force, thus avoiding accumulation on the surface of the electronic control unit and affecting its heat dissipation effect.

[0164] Furthermore, the axial spacing between the motor and the axial fan is also set within the optimal range, so that most of the cooling air blown out by the axial fan flows over the surface of the motor housing, thereby reducing the amount of cooling air that directly enters the motor along the fan axis, and preventing debris and dust attached to the cooling air from entering the motor and accumulating, thus affecting the motor's heat dissipation effect. Attached Figure Description

[0165] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0166] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0167] Figure 1 This is a schematic diagram of the structure of a chainsaw provided in an embodiment of this application;

[0168] Figure 2 for Figure 1 A schematic diagram of the structure after removing the cut parts, battery pack assembly, and handguard baffle;

[0169] Figure 3 A schematic diagram of the internal structure of the main housing of a chainsaw provided in another embodiment of this application;

[0170] Figure 4 for Figure 3 A schematic diagram of the structure after removing the axial fan;

[0171] Figure 5 A schematic diagram of the structure of an axial fan, motor, and electronic control device provided for another embodiment of this application;

[0172] Figure 6 for Figure 5 A schematic diagram of the structure after removing the axial fan;

[0173] Figure 7A schematic diagram of the internal structure of the main housing of a chainsaw provided in another embodiment of this application from another perspective;

[0174] Figure 8 A schematic diagram of the axial fan, motor, and electronic control device provided in another embodiment of this application from another perspective;

[0175] Figure 9 A schematic diagram of the structure of an axial fan and motor provided in another embodiment of this application;

[0176] Figure 10 This is a schematic diagram of the structure of a MOSFET and an axial fan provided in another embodiment of this application;

[0177] Figure 11 A schematic diagram of the structure of the hook and hand guard provided in another embodiment of this application;

[0178] Figures 12a-12d A simplified schematic diagram of the electronic control device and axial fan as provided in another embodiment of this application, showing their orthographic projection on a first plane.

[0179] Explanation of reference numerals and components in the accompanying drawings:

[0180] 100. Power tools / chainsaws / tree chainsaws;

[0181] 10. Main unit housing; 20. Motor / external rotor motor; 30. Electronic control unit; 40. Working assembly / cutting assembly; 50. Battery pack assembly; 60. Grip assembly; 70. Cooling fan / axial fan; 80. Hook; 90. Hand guard plate;

[0182] 101. Air inlet; 102. Air outlet; 103. First housing; 104. Second housing; 105. Shield; 1051. Flow guide cavity; 106. Filter screen; 107. Bottom plane; 108. Guide slot; 109. Battery pack mounting position;

[0183] 201. Output shaft / motor output shaft; 202. Motor housing;

[0184] 301. Heat dissipation surface; 302. Heat dissipation fins; 303. Heat dissipation grooves; 304. Base; 305. MOSFET;

[0185] 401. Saw chain; 402. Guide plate; 403. Protective cover;

[0186] 601. Top handle; 602. Side handle;

[0187] X1, Fan axis; X2, First straight line; A1, Connection line between any position on the MOSFET and the center of the axial end face of the axial fan on the exhaust side; S1, Inlet side; S2, Exhaust side; P, Airflow channel; A2, Boundary line;

[0188] R, the projection circle; R 上 upper semicircle; R 下 B1, the uppermost point of the orthographic projection of the heat dissipation surface onto the first plane in the vertical direction H; B2, the lowermost point of the orthographic projection of the heat dissipation surface onto the first plane in the vertical direction H; C1, the distance from the uppermost point B1 to the lower semicircle R. 下 Tangents; C2, from the lowest point B2 to the lower semicircle R 下 tangent;

[0189] α, The tilt angle of the electronic control device / heat dissipation surface / heat dissipation groove / first straight line X2 relative to the bottom plane and / or third plane of the main unit casing;

[0190] β, the angle between the line A1 connecting any position on the MOS transistor and the center of the axial end face of the axial fan on the outlet side S2, and the fan axis X1;

[0191] The angle formed between ∑ and tangents C1 and C2 relative to the heat dissipation surface;

[0192] L1, the axial distance between the electronic control unit and the axial fan in the extension direction of the fan axis X1;

[0193] L2, the shortest distance from the heat dissipation surface to the fan axis X1;

[0194] L3, width of airflow channel P / shortest distance between motor housing and heat dissipation surface;

[0195] L4, the axial distance between the MOSFET and the axial fan along the extension direction of the fan axis X1;

[0196] The minimum axial distance between L4', the MOSFET, and the axial fan along the extension direction of the fan axis X1;

[0197] The maximum axial distance between L4”, the MOSFET and the axial fan in the extension direction of the fan axis X1;

[0198] L5, the axial distance between the axial fan and the motor in the extension direction of the fan axis X1;

[0199] L6, the shortest distance from the MOSFET to the fan axis X1. Detailed Implementation

[0200] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0201] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0202] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0203] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0204] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0205] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0206] Figure 1 A power tool 100 is shown, extending along three orthogonal spatial directions: length extension direction L, width extension direction W, and height extension direction H. It includes a main housing 10, a motor 20 housed within the main housing 10, an electronic control unit 30, and a working component 40. The motor 20 drives the working component 40 to perform working tasks. The electronic control unit 30 is electrically connected to the motor 20 to control the on / off state of the motor 20. Furthermore... Figure 1 The power tool 100 in this disclosure is a chainsaw 100, and the working component 40 is the cutting component 40. Of course, it can also be other types of power tools. This disclosure does not limit the specific type of power tool.

[0207] See Figures 1-4 , Figure 7 , Figure 11 As shown, the chainsaw 100 includes a main housing 10, a motor 20, an electronic control device 30, a cutting assembly 40, a battery pack assembly 50, a transmission assembly (not shown), and a gripping assembly 60. The motor 20, electronic control device 30, and transmission assembly are disposed inside the main housing 10. The cutting assembly 40 and battery pack assembly 50 are respectively disposed at both ends of the main housing 10 along the length L of the main housing 10. Correspondingly, a battery pack mounting position 109 is provided at the rear end of the main housing 10, and the battery pack assembly 50 is inserted into the battery pack mounting position 109. The cutting assembly 40 is disposed at the front end of the main housing 10 and partially extends into the main housing 10. It is driven by the motor 20 through the transmission assembly. The motor 20 is powered by the battery pack assembly 50. The electronic control device 30 is electrically connected to the motor 20 to control the current flow of the motor 20.

[0208] The cutting assembly 40 includes a saw chain 401 and a guide plate 402. One end of the guide plate 402 is supported inside the main housing 10, and the other end extends protruding outward along the length L of the main housing 10. The guide plate 402 is made of a metal material such as iron. The saw chain 401 has multiple interconnected blades. The guide plate 402 supports the saw chain 401, which is installed in a tensioned state along the periphery of the guide plate 402. For ease of explanation, in the following description, when the chainsaw 100 is placed on a horizontal bearing surface such as the ground, the direction orthogonal to the bearing surface is called the vertical direction H of the chainsaw 100; the direction in which the length direction of the guide plate 402 is projected onto the bearing surface is called the longitudinal direction L of the chainsaw 100, i.e., the longitudinal direction of the main housing 10; and the direction orthogonal to the vertical direction H and the longitudinal direction L of the chainsaw 100 is called the horizontal direction W of the chainsaw 100. Figure 2 As shown, the forward and backward directions (L), the left and right directions (W), and the up and down directions (H) are defined by arrows. The top of the drawing is defined as the top, the bottom of the drawing is defined as the bottom, the outward direction of the drawing is defined as the left, and the inward direction of the drawing is defined as the right.

[0209] The grip assembly 60 includes a top handle 601 and a side handle 602. The top handle 601 is positioned on the upper part of the main housing 10 in the vertical direction (H) of the chainsaw 100, while the side handle 602 is positioned on the left or right side of the main housing 10 in the horizontal direction (W) of the chainsaw 100. Chainsaws 100 with this grip assembly 60 configuration are generally called top-handle chainsaws, also known as tree chainsaws 100, and are mostly used for pruning branches. Users typically carry the chainsaw 100 to the tree with one hand for operation. Compared to other types of chainsaws, the top handle 601 of the tree chainsaw 100 is positioned closer to the cutting assembly 40 at the front end of the main housing 10, increasing the likelihood of the user's hand being cut by flying sawdust. (See [link to relevant documentation]). Figure 11 As shown, a hand guard 90 is also provided above the main housing 10 and between the top handle 601 and the cutting component 40 for safety protection.

[0210] See also Figure 11As shown, to ensure safety, when the chainsaw 100 is not in operation, a protective cover 403 is used to cover the cutting component 40 to prevent the user's hands from coming into contact with the saw chain 401 and causing a safety accident. When the chainsaw 100 is in operation, to prevent the chainsaw 100 from falling due to improper grip by the user, the main housing 10 is provided with at least one hook 80 below the location where the battery pack assembly 50 is located, preferably two hooks. One hook 80 is connected to the user's shoulder strap or belt via a safety rope (not shown in the figure), and the other hook 80 is connected to a fixed object at the user's location via a safety rope (not shown in the figure), thus achieving double safety assurance. Even if the user accidentally lets go, the chainsaw 100 will be prevented from falling to the ground under the action of the safety rope (not shown in the figure) and causing a safety accident. Furthermore, the main housing 10 is also provided with a storage compartment (not shown in the figure) corresponding to the location of the hook 80. The hook 80 is housed in the storage compartment in the storage state and extends out of the storage compartment in the hanging state. The specific shape of the storage compartment is not limited and can be adapted to the shape of the hook 80.

[0211] Based on the usage scenarios of the tree chainsaw 100 and combined with the user's cutting needs, users usually hope that the tree chainsaw 100 has both excellent cutting performance and the advantages of small size and light weight.

[0212] As is well known, to achieve excellent cutting results with the chainsaw 100, the output power of the motor 20 is typically increased to enhance the power required for cutting hard materials such as wood and stone. Higher output power of the motor 20 results in a faster saw chain 401 and better cutting performance, but this also leads to increased heat generation from the motor 20. The electronic control unit 30, which drives the motor 20, also generates significant heat under heavy loads. If the motor 20 and electronic control unit 30 are not cooled in time, the chainsaw 100 will shut down due to overheating. Typically, a cooling fan 70 is installed on the output shaft 201 of the motor 20, rotating with it, or the cooling fan 70 is attached to the output shaft 201 of the motor 20 via a transmission device. Simultaneously, the main housing 10 also has an air inlet 101 and an air outlet 102 for the intake and exhaust of cooling air. During the rotation of the cooling fan 70 driven by the motor 20, the cooling fan 70 can continuously draw cooling air from outside the main unit housing 10 into the interior of the main unit housing 10 through the air inlet 102, and form a cooling air circulation around the motor 20 and the electronic control device 30, so as to timely exhaust the heat inside the main unit housing 10 from the air outlet 102.

[0213] There are several methods for cooling the motor 20 and electronic control device 30. First, a cooling fan 70 can be used to deliver a single stream of cooling air to the upstream and downstream motors 20 and electronic control device 30. However, this increases the overall size of the unit, and the cooling effect on downstream components is less than that on upstream components. Second, the cooling fan 70 can deliver multiple streams of cooling air to the motor 20 and electronic control device 30 separately. This results in multiple streams of cooling air flowing within the main unit casing 10, affecting the heat dissipation of the motor 20 and electronic control device 30.

[0214] Therefore, the chainsaw 100 provided in this embodiment has a reasonable layout of the motor 20, electronic control device 30 and cooling fan 70 inside the main body housing 10, so that a single stream of unidirectional cooling air can cool the motor 20 and the electronic control device 30 at the same time, avoiding the situation where multiple streams of cooling air interfere with each other, ensuring the cooling and heat dissipation effect of the motor 20 and the electronic control device 30, so that the output power of the motor 20 meets the user's cutting needs, while further reducing the overall size and weight of the chainsaw 100.

[0215] Commonly used cooling fans include axial fans and centrifugal fans. In an axial fan, the inlet and outlet directions are parallel to the fan's rotation axis X1. Cooling air enters the axial fan along the rotation axis X1, is pressurized, and then exits along the same direction, achieving a larger airflow and lower air resistance. In a centrifugal fan, the inlet and outlet directions are perpendicular. Cooling air enters the centrifugal fan along its rotation axis X1 and is propelled towards the outer edge of the impeller by centrifugal force for discharge. Under the same airflow and air pressure, axial fans consume less power than centrifugal fans. Furthermore, centrifugal fans are more complex to install and have a larger size. Given that axial fans have high wind speed and airflow, they can quickly dissipate heat from inside the main unit casing 10. At the same time, axial fans can maintain a relatively uniform wind speed during rotation, resulting in a more significant heat dissipation effect. Furthermore, axial fans have low power consumption, small size, light weight, and are easy to install. Therefore, in this embodiment, axial fans 70 are preferred as the cooling fan 70.

[0216] An axial fan 70 is disposed inside the main unit housing 10 and is capable of rotating around the fan axis X1. Correspondingly, the main unit housing 10 has an air inlet 101 and an air outlet 102 communicating with the outside. The axial fan 70 rotates to draw in external cooling air from the air inlet 101 into the main unit housing 10 and exhaust it from the air outlet 102 to the outside of the main unit housing 10. For ease of description, the two sides of the axial fan 70 along the fan axis X1 are defined as the air inlet side S1 and the air outlet side S2, respectively. The path of cooling air flowing from the air inlet 101 to the air inlet side S1 of the axial fan 70 within the main unit housing 10 is defined as the air inlet path of the cooling air, and the path of cooling air flowing from the air outlet side S2 of the axial fan 70 to the air outlet 102 within the main unit housing 10 is defined as the air outlet path of the cooling air. During the operation of the chainsaw 100, the rotation of the axial fan 70 causes a cooling air circulation to form inside the main housing 10 around the motor 20 and the electronic control device 30, thereby timely expelling the heat inside the main housing 10 from the air outlet 102.

[0217] The motor 20 is disposed inside the main housing 10, and is at least located on the motor housing 202 extending in the direction of the motor output shaft 201. The aforementioned axial fan 70 is directly connected to the motor 20 by being mounted on the output shaft 201 of the motor 20. For the DC-powered chainsaw 100, as is well known to those skilled in the art, the commonly used types of motor 20 are DC internal rotor motors and DC external rotor motors. Under the same dimensions (e.g., the same output power and speed of the motor 20), the volume of a DC external rotor motor is generally smaller and the weight of a DC internal rotor motor are also lighter than those of a DC internal rotor motor. Therefore, from the perspective of lightweight and small size, a DC brushless external rotor motor is preferred. In one embodiment of this application, the motor 20 is a DC external rotor motor 20, which includes a fixedly arranged stator coil (not shown in the figure) and an external rotor (not shown in the figure) surrounding the stator coil, an output shaft 201 fixedly connected to the external rotor, and a motor housing 202 extending in the direction of the output shaft 201 of the motor. The external rotor includes a plurality of permanent magnets (not shown in the figure) arranged circumferentially relative to the stator coil. During the operation of the external rotor motor 20, the external rotor drives the output shaft 201 to rotate, thereby driving the axial flow fan 70 to rotate.

[0218] An electronic control device 30 is installed inside the main housing 10 and is electrically connected to the aforementioned external rotor motor 20 to control the current flow of the motor 20.

[0219] See Figure 3 , Figure 5 , Figures 7-8As shown, the axial fan 70, motor 20 and electronic control device 30 are arranged inside the main unit housing 10 such that the orthographic projection of the axial fan 70 on the first plane covers the orthographic projection of the motor 20 on the first plane, and further, the orthographic projection of the axial fan 70 on the first plane covers the orthographic projection of the motor housing 202 on the first plane. At the same time, the orthographic projection of the axial fan 70 on the first plane and the orthographic projection of the electronic control device 30 on the first plane are at least partially coincident or tangent. The first plane is a plane that is perpendicular to the fan axis X1 and parallel to the vertical direction H. It can be simply understood as a plane that extends in the vertical direction H and the front-back direction L of the chainsaw 100.

[0220] The shortest distance from the electronic control device 30 to the fan axis X1 is configured to be greater than the radius R2 of the motor housing 202. The shortest distance can be understood as the shortest vertical distance between the two. The ratio of the shortest distance from the electronic control device to the fan axis X1 to the radius R2 of the motor housing is configured to be between 1.05 and 3. In some embodiments, this ratio can be set to 1.05, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.2, 2.4, 2.5, 2.6, 2.8, or 3. Preferably, it can be set to 1.2. See also... Figure 5 As shown, preferably, the electronic control device 30 and the motor 20 are both located on the same side, i.e., on the air outlet side S2 of the axial fan 70, so that both are located on the air outlet path of the cooling air. Combined with... Figure 9As shown, the diameter D1 of the orthographic projection of the axial fan 70 on the first plane is set to be larger than the outer diameter D2 of the orthographic projection of the motor housing 202 on the first plane. The ratio between the two is configured to be 1 to 3. In some embodiments, the ratio can be configured to 1, 1.1, 1.3, 1.5, 1.7, 1.9, 2.1, 2.3, 2.5, 2.7, 2.8, 2.9, or 3. Preferably, the ratio between the two can be configured to 1.3. Correspondingly, in one embodiment provided by this application, the diameter D1 of the orthographic projection of the axial fan on the first plane is set to 85 mm, and the outer diameter D2 of the orthographic projection of the motor housing 202 on the first plane is set to 64 mm. This setting can increase the air outlet efficiency of the axial fan 70, so that the motor 20, or at least the motor housing 202, can be completely located in the axial cooling air blown out by the air outlet side S2 of the axial fan 70. Furthermore, the edge of the blades of the axial fan 70 is extended to the electronic control device 30. The two are tangent or overlapped in the direction of the fan axis X1. That is, the orthographic projection of the axial fan on the first plane and the orthographic projection of the electronic control device on the first plane are at least partially overlapped or tangent. This arrangement can increase the flow area of ​​the cooling air blown out by the outlet side S2 of the axial fan 70 on the electronic control device 30, thereby achieving the purpose of cooling the motor 20 and the electronic control device 30 simultaneously with a single stream of unidirectional cooling air, and improving the cooling and heat dissipation effect of the motor 20 and the electronic control device 30.

[0221] See Figures 7-8As shown, the orthographic projection of motor 20 on the second plane is at least partially located within the orthographic projection of electronic control device 30 on the second plane. The second plane is a plane parallel to both the fan axis X1 and the vertical direction H. It can also be simply understood as a plane extending parallel to the vertical direction H and the horizontal direction W of chainsaw 100. With this arrangement, motor 20 and electronic control device 30 have at least a partial overlap in the front-rear direction L of chainsaw 100. While keeping the position of motor 20 relative to axial fan 70 unchanged, further moving the position of electronic control device 30 closer to axial fan 70 increases the flow area and airflow of cooling air on its surface, resulting in better cooling. However, if the distance between them is too small, axial fan 70 is prone to deformation after prolonged operation, and the edges of the fan blades may scrape against electronic control device 30, causing unnecessary damage to both. Therefore, in one embodiment of this application, the axial distance L1 from the side of the electronic control device 30 near the axial fan 70 to the axial fan 70 in the extension direction of the fan axis X1 is configured to be 2mm to 50mm. In some embodiments, the axial distance L1 can be configured to be 2mm to 10mm; in some embodiments, the axial distance L1 can be configured to be 10mm to 16.8mm; in some embodiments, the axial distance L1 can be configured to be 16.8mm to 20mm; in some embodiments, the axial distance L1 can be configured to be 20mm to 35mm. In some embodiments, the axial spacing L1 can be configured to be 35mm to 40mm, and in other embodiments, it can be configured to be 40mm to 50mm. In some embodiments, the axial spacing L1 can be configured to be 2mm, 5mm, 8mm, 11mm, 13mm, 15mm, 16mm, 17mm, 18mm, 22mm, 28mm, 33mm, 35mm, 36mm, 38mm, 40mm, 43mm, 45mm, 47mm, 48mm, or 50mm, with a preferred configuration of 16.8mm. This configuration increases the flow area of ​​the cooling air blown from the outlet side S2 of the axial fan 70 onto the electronic control device 30, increasing the airflow and improving the heat dissipation effect. It also provides a safe distance between the axial fan 70 and the electronic control device 30, preventing the fan blades of the axial fan 70 from scraping the electronic control device 30 due to deformation.

[0222] Typically, the surface of the electronic control device 30 is provided with a heat dissipation surface 301 made of metal material for rapid heat dissipation. To effectively improve the heat dissipation effect of the electronic control device 30, the aforementioned heat dissipation surface 301 made of metal material is provided on the surface of the electronic control device 30 near the motor housing 202. In some embodiments, the heat dissipation surface 301 is provided on the surface of the electronic control device 30 opposite to the motor housing 202 in the front-rear direction L. Of course, the aforementioned heat dissipation surface 301 made of metal material can also be provided on other surfaces of the electronic control device 30, and the setting can be adjusted according to the actual situation. More preferably, the electronic control device 30 is arranged parallel to the fan axis X1 inside the main housing 10, such that the heat dissipation surface 301 arranged on it is also arranged parallel to the fan axis X1 and the left-right direction W of the chainsaw 100 inside the main housing 10. The orthographic projection of the motor housing 202 of the motor 20 on the second plane is at least partially located within the orthographic projection of the heat dissipation surface 301 on the second plane. This arrangement increases the area of ​​the heat dissipation surface 301 made of metal facing the axial fan 70, increasing the flow area and air volume of cooling air on the heat dissipation surface 301, thereby quickly and effectively removing the heat dissipated by the electronic control device 30. In other embodiments, the electronic control device 30 may also be disposed within the main housing 10 along the left-right direction W of the chainsaw 100 and at an angle to the fan axis X1. That is, the electronic control device 30 has an extending plane along the left-right direction W of the chainsaw 100, and the angle between the fan axis X1 and this extending plane is configured to -30° to 30°. In some embodiments, the above-mentioned angle may be configured to -30° to -20°; in some embodiments, it may be configured to -20° to -10°; in some embodiments, it may be configured to -10° to 10°; in other embodiments, it may be configured to 10° to 20°; in still other embodiments, it may be configured to 20° to 30°; and in some embodiments, it may be configured to -30°, -25°, -15°, -5°, 5°, 15°, 25°, or 30°. See also Figure 7 and Figure 8 As shown in one embodiment of this application, the heat dissipation surface 301 of the electronic control device 30 is further provided with multiple heat dissipation ribs 302 facing the motor 20. Two adjacent heat dissipation ribs 302 form a heat dissipation groove 303, which can further increase the contact area between the heat dissipation surface 301 and the cooling air, thereby improving the heat dissipation effect of the electronic control device 30.

[0223] It should be noted that the electronic control device 30 and the motor 20 should not be placed too close together. If they are too close, it will obstruct the flow of cooling air blown out by the exhaust side S2 of the axial fan 70. Cooling air cannot flow through the area where the motor housing 202 and the electronic control device 30 are positioned opposite each other and close together, thus having a negative effect on the cooling and heat dissipation of both the motor 20 and the electronic control device 30. See [link / reference] Figure 4 and Figure 6 As shown, an airflow channel P is formed between the motor 20 and the electronic control device 30. This can be simply understood as a certain distance between the motor housing 202 and the heat dissipation surface 301 of the electronic control device 30 to form the airflow channel P. The cooling air blown out from the outlet side S2 of the axial fan 70 can smoothly pass through the airflow channel P. During this process, the cooling air can flow over both the surface of the motor housing 202 and at least part of the heat dissipation surface 301, thereby achieving simultaneous cooling of the motor 20 and the electronic control device 30 by a single stream of unidirectional cooling air. This avoids interference between multiple streams of cooling air and improves the cooling effect of the motor 20 and the electronic control device 30. The shortest distance L2 from the heat dissipation surface 301 to the fan axis X1 is configured to be 33mm to 43.5mm. For ease of understanding, the aforementioned shortest distance L2 can be understood as the shortest vertical distance from the heat dissipation surface 301 to the fan axis X1. In some embodiments, the orthographic projection of the fan axis X1 onto the first plane is projection point U, and the orthographic projection of the heat dissipation surface 301 onto the first plane is projection line Q. A perpendicular line segment V is drawn from projection point U to projection line Q. The length L2 of the perpendicular line segment V is configured to be 33mm to 43.5mm. Projection line Q can be a line segment or a partially curved arc, etc. When projection line Q is a partially curved arc, the perpendicular line segment V can be understood as the shortest line segment from projection point U to projection line Q. In some embodiments, the aforementioned shortest distance L2 / length L2 can be configured to be 33mm to 35.5mm. In some other embodiments, the aforementioned shortest distance L2 / length L2 can be configured to be 35.5mm to 38.5mm. In some still embodiments, the aforementioned shortest distance L2 / length L2 can be configured to be 38.5mm to 43.5mm. In some embodiments, the aforementioned shortest distance L2 / length L2 can be configured to be 33mm, 34mm, etc.

[0224] The lengths are 35.5mm, 36mm, 37.5mm, 38mm, 39.5mm, 40mm, 41.5mm, 42mm, and 43.5mm, with 38.5mm being the preferred option. The motor housing 202 has a first cross-section, which is tangent only to the surface of the motor housing 202. This first cross-section is parallel to the heat dissipation surface 301, and the vertical distance between them is configured to be 1mm to 40mm. This means that the shortest width L3 of the airflow channel P in the radial direction of the motor housing 202, or the shortest distance L3 between the motor housing 202 and the heat dissipation surface 301, is configured to be 1mm to 40mm. Alternatively, the difference between the shortest distance L2 / length L2 and the radius R2 of the motor housing 202 can be used to characterize the shortest width L3 of the airflow channel P in the radial direction of the motor housing 202, or the shortest distance L3 between the motor housing 202 and the heat dissipation surface 301. In some embodiments, the minimum width L3 / minimum distance L3 can be configured to be 1mm to 3.5mm; in some embodiments, the minimum width L3 / minimum distance L3 can be configured to be 3.5mm to 20.5mm; in some embodiments, the minimum width L3 / minimum distance L3 can be configured to be 20.5mm to 32mm; in still other embodiments, the minimum width L3 / minimum distance L3 can be configured to be 32mm to 35mm; in yet another embodiment, the minimum width L3 / minimum distance L3 can be configured to be 35mm to 40mm; and in still other embodiments, the minimum width L3 / minimum distance L3 can be configured to be 1mm, 2.5mm, etc.

[0225] 3mm, 4.5mm, 5mm, 6.5mm, 7mm, 8.5mm, 9mm, 10.5mm, 11mm, 11.5mm, 15mm,

[0226] The thickness can be 17.5mm, 20mm, 22.5mm, 28mm, 30.5mm, 33mm, 36.5mm, or 40mm, with 6.5mm being the preferred option, so that the cooling airflow can pass smoothly through the airflow channel P to simultaneously dissipate heat from the motor 20 and the electronic control device 30.

[0227] Generally, the electronic control device 30 includes a base portion 304 and a MOSFET 305. The MOSFET 305 is located inside the base portion 304 and is used to control the current switching of the motor 20. It is also the main heat source of the electronic control device 30, and the heat dissipation effect of the MOSFET 305 directly affects the overall heat dissipation effect of the electronic control device 30. Therefore, the placement of the MOSFET 305 within the base portion 304 needs to be carefully considered. In fact, the surface of the base portion 304 near the motor 20, that is, the surface opposite to the motor housing in the front-rear direction L, constitutes the aforementioned heat dissipation surface 301. The area where the orthographic projection of the motor 20 on the plane of the heat dissipation surface 301 overlaps with the heat dissipation surface 301, that is, the area on the electronic control device 30 that overlaps with the motor 20 in the front-rear direction L of the chainsaw 100, is a high-speed airflow area. This area is located near both the motor 20 and the axial fan 70. The cooling air velocity and flow rate flowing through this area are greater than those flowing through other areas of the heat dissipation surface 301. Therefore, the cooling effect of the high-speed airflow area on the electronic control device 30 is significantly better than that of other areas. Consequently, it is preferred to place the MOSFET 305 in the base portion 304 within the effective range of this area, that is, the orthographic projection of the MOSFET 305 on the heat dissipation surface 301 is at least partially located within this high-speed airflow area. The orthographic projection of the motor housing 202 on the second plane and the orthographic projection of the heat dissipation surface 301 on the second plane have at least a partial overlap area, and the orthographic projection of the MOSFET 305 on the second plane is at least partially located within the overlap area. For details, see [link to relevant documentation]. Figure 10 As shown, the shortest distance L6 from MOSFET 305 to fan axis X1 is configured to be 33mm to 44mm. That is, the orthographic projection of fan axis X1 on the first plane is projection point U, and the orthographic projection of MOSFET 305 on the first plane is projection line M. A perpendicular line segment Z is drawn from projection point U to projection line M. The length L6 of perpendicular line segment Z is configured to be 33mm to 44mm. Projection line M can be a line segment or a partially curved arc, etc. When projection line M is a partially curved arc, perpendicular line segment Z can be understood as the shortest line segment from projection point U to projection line M. In some embodiments, the shortest distance L6 / length L6 can be configured to be 33mm to 38.6mm. In other embodiments, the shortest distance L6 / length L6 can be configured to be 38.6mm to 44mm. In still other embodiments, the shortest distance L6 / length L6 can be configured to be 33mm, 34.5mm, 35mm, 36.5mm, 37mm, 38.5mm, 39mm, 40.5mm, 41mm, 42.5mm, 43mm, or 44mm. Preferably, it can be configured to be 38.6mm.

[0228] Furthermore, the axial spacing L4 between the MOSFET 305 and the axial fan 70 along the extension direction of the fan axis X1 is configured to be 10mm to 80mm, where L4' is the minimum axial spacing between the MOSFET 305 and the axial fan 70 along the extension direction of the fan axis X1, and L4" is the maximum axial spacing between the MOSFET 305 and the axial fan 70 along the extension direction of the fan axis X1. In some embodiments, the axial spacing L4 can be configured to be 10mm to 21.1mm; in other embodiments, it can be configured to be 21.1mm to 69.4mm; in still other embodiments, it can be configured to be 69.4mm to 80mm; and in some embodiments, it can be configured to be 10mm, 15mm, 20mm, 21.1mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 69.4mm, 70mm, 75mm, or 80mm. Alternatively, see [link to previous text]. Figure 10 As shown, the angle β between the connecting line A1 between any position on the MOS transistor 305 and the center of the axial end face of the axial fan 70 located on the air outlet side S2, and the fan axis X1 can be configured to be 10° to 60°, where β' is the minimum angle between the connecting line A1 and the fan axis X1, and β” is the maximum angle between the connecting line A1 and the fan axis X1. In some embodiments, the above-mentioned angle β can be configured to be 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc. °, preferably, can be set within the range of 20° to 50°. By placing the MOSFET 305 within the substrate 304 as close as possible to the high-speed airflow region of the heat dissipation surface 301 in the direction of the orthogonal projection line of the MOSFET 305 on the heat dissipation surface 301, and simultaneously placing it as close as possible to the axial fan 70 in the direction of the fan axis X1, the heat from the MOSFET 305 can be efficiently transferred to the high-speed airflow region of the heat dissipation surface 301 and carried away by the high-speed circulating cooling air, thereby achieving rapid and efficient cooling.

[0229] As the main heat source inside the main housing 10, the electronic control device 30 is susceptible to malfunction if its temperature rises too quickly or becomes too high. In one embodiment of this application, the temperature of the electronic control device 30 is monitored in real time, and temperature protection measures are implemented based on the temperature rise to prevent the device from malfunctioning due to excessive temperature. Specifically, a temperature detection device (not shown in the figure) is installed on the electronic control device 30 to collect its temperature data. The electronic control device 30 receives the temperature data from the detection device and compares it with a preset temperature threshold to determine if the temperature protection conditions are met. If the conditions are met, the temperature protection strategy is executed. For safety, the preset temperature threshold is preferably set to be greater than or equal to 110°C and less than or equal to 100°C. The upper limit of the preset temperature threshold in the tree chainsaw 100 provided in the above embodiment is set to 110°C. When the detected temperature fed back by the temperature detection device is greater than or equal to 110°C, the electronic control device 30 stops working. When the detected temperature fed back by the temperature detection device is less than or equal to 100°C, the electronic control device 30 restarts and begins working.

[0230] The arrangement of the axial fan 70, motor 20, and electronic control unit 30 inside the main unit housing 10 can also be as follows: (See below) Figures 12a-12d As shown, the orthographic projection of the axial fan 70 on the first plane overlaps with the orthographic projection of the motor 20 on the first plane. Furthermore, the orthographic projection of the axial fan 70 on the first plane overlaps with the orthographic projection of the motor housing 202 on the first plane. Simultaneously, the orthographic projection of the axial fan 70 on the first plane does not overlap with the orthographic projection of the electronic control device 30 on the first plane. Specifically, the orthographic projection of the axial fan 70 on the first plane is a projection circle R, which includes the upper semicircle R in the vertical direction H. 上 and the lower semicircle R 下 A dividing line A2 can be drawn through the center of the projection circle R, perpendicular to the vertical direction H. The portion of the projection circle R above the dividing line A2 is the upper semicircle R. 上 The portion of the projected circle R above the dividing line A2 is the lower semicircle R. 下 The orthographic projection of the heat dissipation surface 301 onto the first plane includes the uppermost endpoint B1 and the lowermost endpoint B2 in the vertical direction H, and the uppermost endpoint B1 and the lowermost endpoint B2 project onto the lower semicircle R of the projection circle R. 下Tangents C1 and C2 are drawn, and the included angle ∑ formed between the two tangents C1 and C2 and opposite to the heat dissipation surface 301 is configured to be greater than or equal to 15°. The first plane is a plane perpendicular to the fan axis X1 and parallel to the vertical direction H. Further, the ratio of the orthographic projection of the electronic control device 30 on the first plane to the orthographic projection of the axial fan 70 on the first plane, and the shortest distance from the electronic control device 30 to the fan axis X1 to the radius R1 of the projection circle R, is configured to be greater than 1 and less than or equal to 2.5. This means that, provided the main unit housing 10 meets the requirements for accommodating the electronic control device 30, it can be placed at any position that meets the above conditions. In some embodiments, the included angle ∑ can be configured to 15°–30°; in some embodiments, it can be configured to 30°–60°; in some embodiments, it can be configured to 60°–90°; in some embodiments, it can be configured to 90°–120°; and in some embodiments, it can be configured to 120°–150°. With this configuration, the cooling air blown out from the outlet side S2 of the axial fan 70 rotates and blows out along the direction of the rotation axis X1 and in a tangential direction to the outer edge of the axial fan 70. The blown cooling air can flow over both the surface of the motor housing 202 and most of the heat dissipation surface 301. See further details. Figure 12d As shown, the electronic control device is also configured to overlap with the motor in the vertical direction H. This configuration can further reduce the size of the chainsaw in the vertical direction H and the front-back direction L, making the whole machine smaller and more compact.

[0231] Based on the reasonable layout of the motor 20, electronic control device 30 and axial fan 70 inside the main housing 10, the cooling air blown out by the air outlet S2 of the axial fan 70 can simultaneously cool the motor 20 and electronic control device 30, improve the heat dissipation effect of the motor 20 and electronic control device 30, and ensure the cutting effect of the tree chainsaw 100.

[0232] In addition, the flow rate and velocity of cooling air are also factors that affect the heat dissipation effect of motor 20 and electronic control device 30. In fact, the heat dissipation effect of motor 20 and electronic control device 30 can also be improved by increasing the air intake efficiency and air exhaust efficiency of axial fan 70.

[0233] To improve the air intake efficiency of the axial fan 70, one embodiment of this application reduces airflow loss during the flow of cooling air from the air intake 101 to the air intake side S1 of the axial fan 70 by bringing the air intake side S1 of the axial fan 70 closer to the air intake 101. Specifically, see... Figure 2 and Figure 7As shown, the main housing 10 has two symmetrical housings along the front-rear direction L, i.e., the front-rear direction L of the chainsaw 100, namely the first housing 103 and the second housing 104. The two housings have a first side and a second side, respectively, which are arranged opposite each other in the left-right direction W. An air inlet 101 is provided on the first side or the second side. An axial fan 70 is coaxially mounted with the motor 20 and is arranged inside the main housing 10 at a position opposite to the air inlet 101 with the fan axis X1 perpendicular to the first side or the second side. That is, the orthographic projection of the axial fan 70 on the first plane is at least partially located within the orthographic projection of the air inlet 101 on the first plane. This arrangement can provide a basis for generating a single stream of unidirectional cooling air inside the main housing 10 and can also reduce the size of the chainsaw 100 in the left-right direction W. Furthermore, within a safe and reasonable range, the air intake side S1 of the axial fan 70 is positioned as close as possible to the air intake port 101 of the host casing 10, so that the air intake path of the cooling air flowing from the air intake port 101 to the air intake side S1 of the axial fan 70 can be shortened to the limit distance, avoiding the occurrence of high airflow loss due to a long air intake path.

[0234] See Figure 1 , Figure 2 and Figure 7 As shown, in another embodiment of this application, the main housing 10 is further provided with a guide shroud 105. Inside the shroud 105, a guide cavity 1051 communicating with the interior of the main housing 10 is formed. An air inlet 101 is formed on the guide shroud 105, and the guide cavity 1051 communicates with the outside through the air inlet 101. The shape of the guide cavity 1051 is adapted to the shape of the axial fan 70. The axial fan 70 is at least partially placed inside the guide cavity 1051. The guide shroud 105 can guide the cooling air drawn in from the air inlet 101 to the air intake side S1 of the axial fan 70, preventing the cooling air from dissipating along the air intake path and achieving the purpose of reducing airflow loss.

[0235] Regarding improving the airflow efficiency of the axial fan 70, one embodiment of this application achieves this by increasing the diameter R1 of the axial fan 70 while meeting space requirements. Alternatively, in the embodiment with the guide shroud 105, the shortest distance between the inner wall of the guide cavity 1051 and the edge of the axial fan blades 70 can be further controlled. If the distance between the edge of the axial fan blades and the inner wall of the guide cavity 1051 is too large, during operation, some of the cooling air blown out from the outlet side S2 of the axial fan 70 will flow back to the inlet side S1 and be discharged again through the axial fan 70. This cycle repeats, resulting in a decrease in the amount of cooling air blown out from the outlet side S2 of the axial fan 70 and flowing towards the motor 20 and electronic control device 30, thus reducing the airflow efficiency. If the distance between the edge of the axial fan 70 blade and the inner wall of the guide cavity 1051 is too small, the blade of the axial fan 70 will deform after long-term operation. During rotation, the edge of the blade will easily scratch the inner wall of the guide cavity 1051, and both the guide cover 105 and the axial fan 70 will be damaged to varying degrees, increasing the cost of replacement and maintenance. Therefore, by configuring the shortest distance between the inner wall of the flow guide cavity 1051 and the fan axis X1 to be 42.8mm to 52.5mm, in some embodiments the shortest distance can be configured to be 42.8mm to 44mm, in other embodiments the shortest distance can be configured to be 44mm to 48.5mm, in still other embodiments the shortest distance can be configured to be 48.5mm to 52.5mm, and in some embodiments the shortest distance can be configured to be 42.8mm, 44mm, 45.5mm, 46mm, 47.5mm, 48mm, 49.5mm, 50mm, 50.5mm, 51mm, or 52.5mm, preferably 44mm. This can also be visually represented by the fact that the shortest distance from the inner wall of the flow guide cavity 1051 to the edge of the axial fan blade 70 is configured to be 0.3mm to 10mm. In some embodiments, this shortest distance is configured to be 0.3mm to 1.5mm; in other embodiments, it is configured to be 1.5mm to 4mm; in still other embodiments, it is configured to be 4mm to 7.5mm; in yet another embodiment, it is configured to be 7.5mm to 10mm; and in some embodiments, it is configured to be 0.3mm. The minimum distances are 1mm, 1.5mm, 1.75mm, 2mm, 3mm, 4.5mm, 5.5mm, 7mm, 8.5mm, and 10mm, with 1.5mm being the preferred option. By setting the shortest distance between the edge of the axial fan 70 blades and the inner wall of the guide cavity 1051 within the optimal range, the probability of backflow of cooling air at the edge of the axial fan 70 blades is reduced, thus improving airflow efficiency. On the other hand, the service life of the axial fan 70 and the guide shroud 105 is also increased, reducing replacement and maintenance costs.

[0236] During the operation of the tree chainsaw 100, cutting trees generates dust and wood chips. Simultaneously, to ensure sufficient cooling for the motor 20 and electronic control device 30 inside the main housing 10, adequate cooling air must be continuously supplied to the interior of the main housing 10. Therefore, the small dust particles and wood chips generated by the tree chainsaw 100 also enter the interior of the main housing 10 along with the cooling air. As the cooling air flows towards the motor 20 and electronic control device 30, the dust and wood chips carried in the cooling air enter the interior of the motor 20 and / or adhere to the surface of the electronic control device 30, such as the heat dissipation surface 301 and the heat dissipation groove 303. After a period of time, the accumulation of dust and wood chips inside the motor 20 and on the heat dissipation surface 301 and heat dissipation groove 303 of the electronic control device 30 will affect the heat dissipation effect of the motor 20 and the electronic control device 30. Therefore, how to prevent the accumulation of dust and wood chips inside the motor 20 and on the electronic control device 30 is another factor affecting the heat dissipation effect of the motor 20 and the electronic control device 30.

[0237] Solutions to the above problems can be considered from the following perspectives: first, how to prevent dust and wood chips from entering the interior of the main unit housing 10 along with the cooling air; second, how to prevent dust and wood chips from accumulating on the surface of the electronic control device 30; and third, how to prevent dust and wood chips from accumulating inside the motor 20.

[0238] See Figures 1-2 As shown in one embodiment of this application, a filter screen 106 is provided on the air inlet 101 of the main unit housing 10 to filter out most of the large particles of dust and wood chips, blocking the path of dust and wood chips into the interior of the main unit housing 10 from the initial source of cooling air entering the main unit housing 10. Parameters such as the mesh size of the filter screen 106 also need to be carefully considered. If the mesh size of the filter screen 106 is too large, it will hinder the smooth entry of cooling air into the air inlet 101, affecting the air intake efficiency of the cooling air. If the mesh size of the filter screen 106 is too small, it will not be able to effectively filter out large particles of dust and wood chips. The mesh size of the filter 106 is configured from 10 to 50 meshes. In some embodiments, the mesh size is configured from 10 to 20 meshes; in others, it is configured from 20 to 30 meshes; in still others, from 30 to 40 meshes; in yet another embodiment, it is configured from 40 to 50 meshes; and in some embodiments, it is configured as 15, 25, 35, or 45 meshes, with 30 meshes being the preferred configuration. The total air inlet area of ​​the filter 106 is in the range of 600 mm². 2 ~2000mm 2 This is to achieve a balance between air intake efficiency and filtration effect.

[0239] In addition, dust and sawdust accumulating on the surface of the electronic control device 30 need to be cleaned promptly, otherwise it will affect the heat dissipation of the electronic control device 30. Therefore, provided that the internal space requirements of the main unit housing 10 are met, the electronic control device 30 can be placed at an angle. Under the combined action of gravity and cooling airflow, the dust and sawdust on the surface of the electronic control device 30 will fall to the bottom of the main unit housing 10. See also... Figure 4 and Figure 7 As shown, in one embodiment of this application, the electronic control device 30 and the motor 20 are arranged along the length L of the main housing 10. The electronic control device 30 is positioned on the air outlet path of the cooling air and close to the axial fan 70 to increase the airflow and air velocity of the cooling air passing through the heat dissipation surface 301 on the electronic control device 30. The electronic control device 30 is arranged vertically or obliquely relative to the bottom plane 107 of the main housing 10. Preferably, the electronic control device 30 extends obliquely towards the first reference plane along the first straight line X2. The first reference plane is a plane parallel to both the fan axis X1 and the front-rear direction L. Dust and wood chips adhering to the surface of the electronic control device 30 slide down to the bottom plane 107 of the main housing 10 under the action of gravity and / or wind. The bottom plane 107 is parallel to the front-rear direction L of the main housing 10 and perpendicular to the rotation plane of the axial fan 70. That is, the bottom plane 107 is parallel to the front-rear direction L and the left-right direction W of the chainsaw 100, respectively. The rotation plane is perpendicular to the fan axis X1, that is, parallel to the front-rear direction L and the up-down direction H of the chainsaw 100, respectively. The bottom plane 107 is on the same plane as the first reference plane. The electronic control device 30 includes an upper end near the top handle 601 and a lower end opposite to the upper end. When the electronic control device 30 is tilted relative to the first reference plane, it can be positioned at a point where its lower end at least partially overlaps with the orthographic projection of the motor 20 on the first reference plane. Figures 3-6 , Figure 12d As shown, this configuration can further reduce the size of the chainsaw in the vertical direction H and the front-back direction L, making the overall machine smaller and the structure more compact.

[0240] In detail, the main housing 10 includes a first housing 103 and a second housing 104 that are mated together. Guide slots 108 are provided on the first housing 103 and / or the second housing 104. It should be noted that when installing components inside the main housing 10, components are installed into one of the first housing 103 and the second housing 104. One side of the housing has a guide slot 108, and the electronic control device 30 is inserted along the guide slot 108. The other side of the housing may also have a guide slot 108, or it may not. When a guide slot 108 is provided, the guide slots 108 on both sides need to be aligned when the first housing 103 and the second housing 104 are mated. The guide slots 107 are provided along the left-right direction W of the chainsaw 100. When the first housing 103 and the second housing 104 are mated, the left or right side of one side of the housing is open, and the electronic control device 30 is inserted into one side of the housing along the open left or right direction, facilitating the installation of the electronic control device 30. Given that the surface of the electronic control device 30 near the motor 20 in the above embodiment constitutes a heat dissipation surface 301, that is, the side of the electronic control device 30 opposite to the motor housing 202 in the front-rear direction L constitutes a heat dissipation surface 301, the heat dissipation surface 301 is preferably parallel to the fan axis X1 of the axial fan 70, that is, it extends along the left-right direction W of the chainsaw 100. At the same time, the heat dissipation surface 301 is at least partially disposed in the airflow channel P. When the cooling air in the airflow channel P flows through the heat dissipation surface 301, a large amount of dust and sawdust in the cooling air will also adhere to it. Therefore, on the heat dissipation surface 301, under the premise that the electronic control device 30 is inclined relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10, the heat dissipation surface 301 is also configured to be inclined relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10. That is, the heat dissipation surface 301 extends approximately along the heat dissipation plane, and the heat dissipation plane is inclined relative to the first reference plane, so that dust and wood chips slide off the heat dissipation surface 301 onto the bottom plane 107 and / or the first reference plane of the main unit housing 10 under the action of gravity and / or wind.

[0241] When the electronic control device 30 and its heat dissipation surface 301 are configured to be tilted relative to the bottom plane 107 and / or the first reference plane of the main housing 10, the setting of the tilt angle α is also crucial. If the tilt angle α is too large, the electronic control device 30 and its heat dissipation surface 301 will be positioned too close to the bottom plane 107 and / or the first reference plane, or even nearly parallel, and dust and wood chips adhering to the electronic control device 30 and its heat dissipation surface 301 will not be able to slide off, and will still accumulate. If the tilt angle α is too small, the electronic control device 30 will be positioned at such a small tilt angle α within the limited space inside the main housing 10, which will reduce the distance between the electronic control device 30 and the motor 20, and will obstruct the cooling air flowing through the airflow channel P, which is not conducive to the effective heat dissipation of the motor 20 and the electronic control device 30. After comprehensive consideration, the tilt angle α of the electronic control device 30 and the heat dissipation surface 301 relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10, that is, the tilt angle α of the first straight line X2 relative to the bottom plane 107 and / or the first reference plane, is configured to be greater than 90° and less than or equal to 150°. In some embodiments, the above-mentioned tilt angle α can be configured to be 90° to 110°, in other embodiments, the above-mentioned tilt angle α can be configured to be 110° to 115°, and in still other embodiments, the above-mentioned tilt angle α can be configured to be 115° to 115°. In some embodiments, the tilt angle α can be configured to be 120° to 125°. In other embodiments, the tilt angle α can be configured to be 125° to 130°. In still other embodiments, the tilt angle α can be configured to be 130° to 150°. In some embodiments, the tilt angle α can be configured to be 105°, 108°, 111°, 114°, 117°, 120°, 125°, 130°, 135°, 140°, 145°, or 150°. Preferably, it can be configured to be 120°. This configuration allows for good airflow in the airflow channel P, resulting in excellent heat dissipation for the motor 20 and the electronic control device 30. Furthermore, dust and wood chips adhering to the heat dissipation surface 301 can slide down to the bottom plane 107 and / or the first reference surface of the main unit housing 10 under the influence of gravity and / or wind, thereby preventing dust and wood chips from accumulating on the electronic control device 30 and its heat dissipation surface 301.

[0242] See Figures 7-8As shown, in one of the above embodiments, the heat dissipation surface 301 of the electronic control device 30 has multiple heat dissipation fins 302. Compared with a single-plane heat dissipation surface 301, the heat dissipation surface 301 with multiple heat dissipation fins 302 has a larger heat dissipation surface area and better heat dissipation effect. Similarly, each heat dissipation fin 302 and the heat dissipation groove 303 formed by two adjacent heat dissipation fins 202 and the heat dissipation surface 301 extend along the direction of the first straight line X2. The first straight line X2 is also perpendicular or inclined relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10. It should be noted that when the heat dissipation surface 301 is perpendicular to the bottom plane 107 and / or the first reference plane of the main unit housing 10, the first straight line X2, which is consistent with the extending direction of the heat dissipation fins 302 and the heat dissipation groove 303, is also perpendicular to the bottom plane 107 and / or the first reference plane of the main unit housing 10. When the heat dissipation surface 301 is tilted relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10, the first straight line X2, which is consistent with the extending direction of the heat dissipation fins 302 and the heat dissipation grooves 303, is also tilted relative to the bottom plane 107 and / or the first reference plane of the main unit housing 10, and the tilt angle α is consistent.

[0243] The axial fan 70 in this application is directly mounted on the output shaft 201 of the motor 20. The distance between the motor 20 and the axial fan 70 along the fan axis X1 needs careful consideration. If the axial distance is too large, the amount of cooling air blown out from the outlet side S2 of the axial fan 70 into the motor 20 increases, and the probability of dust and wood chips carried in the cooling air entering the motor 20 also increases. After prolonged use, dust and wood chips will accumulate, significantly affecting the heat dissipation of the motor 20. If the axial distance is too small, the fan blades of the axial fan 70 may deform after prolonged operation, causing the blade edges to scrape against the motor 20 during rotation, resulting in wear. See also... Figure 8As shown, in one embodiment of this application, the motor housing 202 includes a front end portion disposed near the axial fan 70 and a rear end portion opposite to the front end portion. In the extension direction of the fan axis X1, the axial distance L5 between the front end portion of the motor housing 202 and the axial fan 70 can be configured to be 0.5mm to 6mm. This can be simply understood as the axial distance L5 between the axial fan 70 and the motor 20 in the extension direction of the fan axis X1 being configured to be 0.5mm to 6mm. In some embodiments, the axial distance L5 can be configured to be 0.5mm to 1mm; in some embodiments, it can be configured to be 1mm to 2mm; in some embodiments, it can be configured to be 2mm to 3mm; in still others, it can be configured to be 3mm to 4mm; in yet still others, it can be configured to be 4mm to 5mm; in still others, it can be configured to be 5mm to 6mm; and in some embodiments, it can be configured to be 0.5mm, 1.2mm, 1.5mm, or 1.8mm.

[0244] The thicknesses are 2.2mm, 2.5mm, 2.8mm, 3.2mm, 3.5mm, 3.9mm, 4.2mm, 4.5mm, 5.2mm, 5.6mm, and 6mm, with 2.2mm being the preferred configuration. A low-pressure airflow zone is formed between the front end of the motor housing 202 and the axial fan 70. The front end of the motor housing 202 has an airflow outlet communicating with the low-pressure airflow zone, and the rear end of the motor housing 202 has an airflow inlet communicating with the internal space of the main unit housing 10. With this configuration, after the cooling air flowing from the outlet side S2 of the axial fan 70 passes over the surface of the motor housing 202, at least a portion of the cooling air enters the interior of the motor housing 202 from the airflow inlet and flows out to the low-pressure airflow zone from the airflow outlet. Simply put, most of the cooling air blown from the outlet side S2 of the axial fan 70 flows along the fan axis X1 direction over the surface of the motor housing 202, reducing the amount of cooling air directly entering the interior of the motor 20 along the fan axis X1 direction. When cooling air flows over the surface of the motor housing 202 and the heat dissipation surface 301 of the electronic control device 30, the dust and debris carried in the cooling air will fall to the bottom plane 107 and / or the first reference surface of the main unit housing 10 under its own gravity. This allows the dust and debris attached to the heat dissipation surface 301 to slide down to the bottom plane 107 and / or the first reference surface of the main unit housing 10 under the action of gravity and / or wind force due to the tilted arrangement of the electronic control device 30 and the heat dissipation surface 301, or even the heat dissipation groove 303.

[0245] Based on the above-mentioned configuration of the electronic control device 30, motor 20 and axial fan 70, dust and wood chips that enter the main unit housing 10 along with the cooling air can fall onto the bottom plane 107 of the main unit housing 10 under the action of gravity and / or wind force, avoiding accumulation on the heat dissipation surface 301 of the electronic control device 30 and the inside of the motor 20, thus affecting the heat dissipation effect of both.

[0246] Once dust and sawdust fall onto the bottom surface 107 of the main unit housing 10, they need to be promptly expelled to the outside of the main unit housing 10 to prevent them from being blown back up by the circulating cooling air inside the main unit housing 10. See further details. Figure 7 As shown, a chip removal port 102 communicating with the outside is provided on the bottom of the main housing 10. When the electronic control device 30 and its heat dissipation surface 301, and even its heat dissipation groove 303, are configured to be inclined relative to the bottom plane 107 and / or the first reference plane of the main housing 10, the orthographic projection of the electronic control device 30 on the bottom plane 107 of the main housing 10 is tangent to or partially intersects with the orthographic projection of the chip removal port 102 on the bottom plane 107 of the main housing 10. Alternatively, the orthographic projection of the electronic control device 30 on the bottom plane 107 of the main housing 10 extends along the front-back direction of the chainsaw 100 to form a first orthographic projection plane, and the orthographic projection of the chip removal port 102 on the bottom plane 107 of the main housing 10 at least partially intersects with the first projection plane. Or, the imaginary extension of the first straight line X2 of the electronic control device 30 and its heat dissipation surface 301, and even its heat dissipation groove 303, is configured to pass through the chip removal port. This configuration allows dust and sawdust on the electronic control device 30 to slide directly through the chip discharge port 102 on the bottom plane 107 of the main housing 10 and be discharged to the outside of the main housing 10. The orthographic projection of the motor housing 202 on the first reference plane and the orthographic projection of the chip discharge port 102 on the first reference plane at least partially coincide. Dust and sawdust in the cooling airflow flowing over the surface of the motor housing 202 can fall directly through the chip discharge port 102 on the bottom plane 107 of the main housing 10 to the outside of the main housing 10 under the action of gravity. Since the main housing 10 also has an air outlet 102 for discharging cooling air, in order to simplify the structure of the main housing 10, it is preferable to set the air outlet 102 on the bottom plane 107 of the main housing 10 so as to also have a chip discharge function, that is, at least part of the chip discharge port 102 constitutes the air outlet 102.

[0247] Furthermore, since the user will operate the tree saw 100 at a high altitude, the dimensions of the main housing 10 in the longitudinal direction L of the chainsaw 100 need to be reduced to meet the user's needs for convenient operation and transportation. Since the battery pack assembly 50 is located at the rear end of the main housing 10, the electronic control device 30 can effectively utilize the space between the motor 20 and the battery pack assembly 50, thereby reducing the length of the main housing 10 in the longitudinal direction L of the chainsaw 100. Further, the battery pack assembly 50 can be positioned parallel to the electronic control device 30 at the rear end of the main housing 10, with the orthographic projection of the battery pack assembly 50 on the second plane overlapping the orthographic projection of the electronic control device 30 on the second plane, further reducing the length of the main housing 10 in the vertical direction H of the chainsaw 100. It should be noted that the area of ​​the orthographic projection of the electronic control device 30 on the second plane is smaller than the area of ​​the orthographic projection of the battery pack assembly 50 on the second plane. Therefore, the electronic control device 30 can be accommodated in the space between the battery pack assembly 50 and the motor 20 in the main housing 10. There is no need to open up new space for the electronic control device 30. This makes the arrangement of the motor 20, the electronic control device 30 and the axial fan 70 inside the main housing 10 more compact, and the main housing 10 is smaller in size, which has the advantage of miniaturization.

[0248] The chainsaw 100 provided in the above embodiments selects a motor 20, an electronic control device 30, and an axial fan 70 adapted to the cutting requirements, and arranges these three components rationally within the main housing 10. This achieves efficient heat dissipation for the motor 20 and the electronic control device 30, and further reduces the overall size and weight of the machine, meeting the lightweight requirements of the tree chainsaw 100 and making it easy for users to hold and carry with one hand. The actual output power of the motor 20 affects the rotation speed of the saw chain 401 and further affects the cutting effect of the chainsaw 100. Therefore, under the premise of meeting good heat dissipation requirements, the higher the rated output power of the motor 20, the higher the upper limit of the rotation speed of the saw chain 401, and the better the cutting performance of the chainsaw 100.

[0249] In some embodiments, the rated input power of motor 20 is greater than or equal to 1200W and less than or equal to 4000W, the ratio of the rated input power of motor 20 to the bare weight of chainsaw 100 is greater than or equal to 778W / Kg, and the bare weight of chainsaw 100 is less than or equal to 3.5Kg. Preferably, the rated input power of motor 20 is greater than or equal to 2000W and less than or equal to 3000W, and the bare weight of chainsaw 100 is less than or equal to 3Kg. In some embodiments, the rated input power of motor 20 is 2400W, and the bare weight of chainsaw 100 is 2.55Kg. In other embodiments, the rated input power of motor 20 is 1500W, and the bare weight of chainsaw 100 is...

[0250] 1.8Kg. In some other embodiments, the rated input power of the motor 20 is 3000W, and the bare weight of the chainsaw 100 is 2.87Kg. It should be noted that the bare weight of the chainsaw 100 is the weight of the chainsaw 100 without the guide plate 402, the saw chain 401, and the battery pack assembly 50.

[0251] In some embodiments, the rated input power of the motor 20 is greater than or equal to 1200W and less than or equal to 4000W, the total weight of the chainsaw 100 is greater than or equal to 1.8Kg and less than or equal to 4.5Kg, and the ratio of the rated input power of the motor 20 to the total weight of the chainsaw 100 is greater than or equal to 467W / Kg. Preferably, the rated input power of the motor 20 is greater than or equal to 2000W and less than or equal to 3000W, and the total weight of the chainsaw 100 is less than or equal to 4.2Kg. In some embodiments, the rated input power of the motor 20 is 2400W, and the total weight of the chainsaw 100 is 4.15Kg. It should be noted that the total weight of the chainsaw 100 is the weight of the chainsaw 100 with the guide plate 402, the saw chain 401, and the battery pack assembly 50 assembled.

[0252] In some embodiments, the ratio of the rated input power of the motor 20 to the bare volume of the chainsaw 100 is greater than or equal to 0.162 W / cm². 3 In some embodiments, the rated input power of the motor 20 is 2400W, and the length, width, and height of the chainsaw 100 are 31.6cm, 20.4cm, and 21.0cm, respectively, with a volume of 13537.44cm². 3 The ratio of the rated input power of motor 20 to the bare volume of chainsaw 100 is 0.1773 W / cm². 3 It should be noted that the bare volume of the chainsaw 100 refers to the volume of the chainsaw 100 without the guide plate 402, saw chain 401, and battery pack assembly 50 installed.

[0253] To verify the heat dissipation performance of the chainsaw 100 provided in this application, a commonly available chainsaw using a centrifugal fan as its cooling fan was selected for a physical comparison test. Under the same comparison dimensions (e.g., the same cutting conditions, the same initial temperature), when the saw chain speed 401 of both chainsaws was greater than or equal to 18 m / s, the temperature rise difference inside the main unit casing 10 of both chainsaws was measured within the same time period. The comparison shows that the temperature rise difference of the chainsaw 100 provided in this application is at least 15% less than that of the chainsaw using a centrifugal fan in the comparative example, demonstrating excellent heat dissipation performance. Furthermore, the chainsaw is smaller and lighter, better meeting the user's need for portable use for cutting in trees.

[0254] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A chain saw extending along three orthogonal spatial directions of a front-rear direction L, a left-right direction W, and an up-down direction H, comprising: a main housing extending along the front-rear direction L, the main housing being provided with an air inlet and an air outlet communicating with the outside; a guide plate mounted to the main housing; a chain mounted on the guide plate; a holding assembly arranged on the main housing; a fan arranged in the main housing, the fan being configured to suck cooling air from the air inlet into the interior of the main housing; a motor arranged in the main housing, the motor being drivingly connected with the fan; an electronic control device arranged in the main housing and electrically connected with the motor to control the operation of the motor; characterized in that the fan is configured as an axial fan, the axial fan being rotatable about a fan axis X1, a projection of the axial fan on a first plane at least partially overlaps or is tangent to a projection of the electronic control device on the first plane, the first plane being a plane perpendicular to the fan axis X1 and parallel to the up-down direction H; and in the extension direction of the fan axis X1, an axial spacing L1 between the axial fan and the electronic control device is configured to be less than or equal to 50 mm.

2. The chain saw of claim 1, wherein axial sides of the axial fan are defined as an air inlet side and an air outlet side respectively, the motor and the electronic control device are arranged at the air outlet side of the axial fan, a projection of the motor on a second plane is at least partially located within a projection of the electronic control device on the second plane, the second plane being a plane parallel to both the fan axis X1 and the up-down direction H.

3. The chain saw of claim 2, wherein the motor includes a motor housing extending in the direction of a motor output shaft, the electronic control device includes a heat dissipation surface arranged opposite to the motor housing in the front-rear direction L, a projection of the fan axis X1 on the first plane is a projection point U, a projection of the heat dissipation surface on the first plane is a projection line Q, a perpendicular line segment V is drawn from the projection point U to the projection line Q, a length L2 of the perpendicular line segment V is configured to be 33 mm to 43.5 mm.

4. The chain saw of claim 3, wherein the electronic control device includes a base body and a MOS tube, the MOS tube is arranged in the base body, a side surface of the base body opposite to the motor housing in the front-rear direction L is provided with the heat dissipation surface, a projection of the motor housing on the second plane at least partially overlaps with a projection of the heat dissipation surface on the second plane, a projection of the MOS tube on the second plane is at least partially located within the overlapping area.

5. The chain saw of claim 4, wherein in the extension direction of the fan axis X1, an axial spacing L4 between the MOS tube and the axial fan is configured to be 10 mm to 80 mm.

6. The chain saw of claim 4, wherein a projection of the fan axis X1 on the first plane is a projection point U, a projection of the MOS tube on the first plane is a projection line M, a perpendicular line segment Z is drawn from the projection point U to the projection line M, a length L6 of the perpendicular line segment Z is configured to be 33 mm to 44 mm.

7. The chain saw of claim 2, wherein The motor is provided with a motor housing extending in the direction of a motor output shaft, the motor housing including a front end portion disposed close to the axial flow fan and a rear end portion opposite to the front end portion, In the extension direction of the fan axis X1, the axial distance L5 between the front end portion of the motor housing and the axial flow fan is configured to be 0.5mm-6mm.

8. The chain saw of claim 7, wherein The area between the front end portion of the motor housing and the axial flow fan forms an airflow low pressure area, the front end portion of the motor housing is provided with an airflow outlet communicating with the airflow low pressure area, and the rear end portion of the motor housing is provided with an airflow inlet communicating with the internal space of the main machine shell, After the cooling air flowing out of the air outlet side of the axial flow fan flows through the surface of the motor housing, at least part of the cooling air enters the internal space of the motor housing from the airflow inlet and flows out of the motor housing to the airflow low pressure area.

9. A chain saw extending along three orthogonal spatial directions of a front-rear direction L, a left-right direction W and an up-down direction H, the chain saw comprising: a main machine shell extending along the front-rear direction L, the main machine shell being provided with an air inlet and an air outlet communicating with the outside; a guide plate mounted to the main machine shell; a chain installed on the guide plate; a holding assembly provided on the main machine shell; a fan provided in the main machine shell, the fan sucking cooling air from the air inlet into the internal space of the main machine shell and discharging the cooling air from the air outlet to the outside of the main machine shell; a motor provided in the main machine shell, the motor being drivingly connected with the fan, the motor being provided with a motor housing extending in the direction of a motor output shaft; an electronic control device provided in the main machine shell and electrically connected with the motor to control the operation of the motor; characterized in that the fan is configured as an axial flow fan, the axial flow fan being rotatable about a fan axis X1, and a cooling air flow path flowing from the axial flow fan to the air outlet is defined as an air outlet path; the electronic control device is provided on the air outlet path of the cooling air, the electronic control device including a heat dissipation surface provided opposite to the motor housing in the front-rear direction L, the heat dissipation surface extending substantially along a heat dissipation plane, the heat dissipation plane being obliquely disposed relative to a first reference plane, the first reference plane being a plane parallel to both the fan axis X1 and the front-rear direction L; a normal projection of the axial flow fan on a first plane is a projection circle, the projection circle including an upper half circle and a lower half circle in the up-down direction H, a normal projection of the heat dissipation surface on the first plane includes an uppermost end point and a lowermost end point in the up-down direction H, and a tangent line is drawn from the uppermost end point and the lowermost end point to the lower half circle of the projection circle, an included angle ∑ opposite to the heat dissipation surface between the two tangent lines is configured to be greater than or equal to 15°, and the first plane is a plane perpendicular to the fan axis X1 and parallel to the up-down direction H.

10. The chain saw of claim 9, wherein, A ratio of the shortest distance from the heat dissipation surface to the fan axis X1 to the radius R1 of the projection circle is configured to be greater than 1 and less than or equal to 2.

5.

11. The chain saw of claim 9, wherein, The electronic control device is arranged on the outflow side of the axial flow fan, and the electronic control device comprises a heat dissipation surface arranged opposite to the motor housing in the front-rear direction L, and a flow channel is formed between the heat dissipation surface and the motor housing, and the cooling air flowing out of the outflow side of the axial flow fan flows through the flow channel, and the cooling air flows through the surface of the motor housing and at least part of the heat dissipation surface.

12. The chain saw of any of claims 9-11, characterized by The heat dissipation surface protrudes in the direction of the motor and is provided with a plurality of heat dissipation ribs arranged at intervals, and two adjacent heat dissipation ribs form a heat dissipation groove, and the extension direction of the heat dissipation groove is perpendicular to the fan axis X1.

13. The chain saw of any of claims 9-11, characterized in that The bottom of the main machine shell is provided with a chip removal opening communicating with the outside, and the projection of the heat dissipation surface on the first reference plane at least partially coincides with or is tangent to the projection of the chip removal opening on the first reference plane. And / or, the projection of the motor housing on the first reference plane at least partially coincides with the projection of the chip removal opening on the first reference plane.

14. An electric power tool extending along three orthogonal spatial directions of a front-rear direction L, a left-right direction W, and an up-down direction H, the electric power tool comprising: a main machine shell provided with an air inlet and an air outlet communicating with the outside; a fan arranged in the main machine shell and configured to draw cooling air from the air inlet into the interior of the main machine shell; a motor arranged in the main machine shell and drivingly connected with the fan, the motor being provided with a motor housing extending in the direction of a motor output shaft; an electronic control device arranged in the main machine shell and electrically connected with the motor to control the operation of the motor; characterized in that the fan is configured as an axial flow fan, the axial flow fan being rotatable about a fan axis X1, and the axial flow fan being defined with an air inlet side and an air outlet side on the two sides in the axial direction of the axial flow fan; the motor and the electronic control device are arranged at the air outlet side of the axial flow fan, the electronic control device comprising a heat dissipation surface arranged opposite to the motor housing in the front-rear direction L, a flow channel being formed between the heat dissipation surface and the motor housing, and the cooling air flowing out of the air outlet side of the axial flow fan flows through the flow channel, and the cooling air flows through the surface of the motor housing and at least part of the heat dissipation surface.

15. The power tool of claim 14, wherein, The projection of the axial flow fan on a first plane at least partially coincides with or is tangent to the projection of the electronic control device on the first plane, the first plane being a plane perpendicular to the fan axis X1 and parallel to the up-down direction H; and in the extension direction of the fan axis X1, the axial spacing L1 between the axial flow fan and the electronic control device is configured to be 2mm-50mm. Alternatively, the heat dissipation surface extends substantially along a heat dissipation plane, the heat dissipation plane is arranged obliquely relative to a first reference plane, the first reference plane is a plane parallel to both the fan axis X1 and the front-rear direction L; the axial flow fan has a right projection on a first plane, the right projection is a projection circle, the projection circle includes an upper half circle and a lower half circle in the up-down direction H, the heat dissipation surface has a right projection on the first plane, the right projection includes an uppermost end point and a lowermost end point in the up-down direction H, tangent lines are drawn through the uppermost end point and the lowermost end point to the lower half circle of the projection circle, and an included angle ∑ opposite to the heat dissipation surface between the two tangent lines is configured to be greater than or equal to 15°, and the first plane is a plane perpendicular to the fan axis X1 and parallel to the up-down direction H.

Images