CN114054847A

CN114054847A - Power tool

Info

Publication number: CN114054847A
Application number: CN202010778982.2A
Authority: CN
Inventors: 刘兵建; 张响亮; 吉绍山
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2022-02-18

Abstract

The present invention provides a power tool, including: a motor; a tool housing including a motor housing accommodating a motor and a grip housing; the fan is driven by the motor to rotate to generate cooling air flow, and the tool shell is provided with an air flow channel; the airflow channel comprises a first airflow channel and a second airflow channel which are relatively independent; the battery pack is used for supplying power to the motor and comprises a shell and a battery core accommodated in the shell, the shell comprises an air inlet and an air outlet, the air inlet and the air outlet are communicated to form a battery pack air flow passage, and when the battery pack is combined to the tool shell, the battery pack air flow passage is communicated with the first air flow passage; a controller for controlling the motor, at least a portion of the controller being disposed in the second airflow path. According to the power tool disclosed by the invention, the battery pack and the controller are respectively cooled through the two independent air flow channels, so that the cooling efficiency is improved, and the requirement of cutting operation is met.

Description

Power tool

Technical Field

The invention relates to a power tool, in particular to a power tool powered by a battery pack.

Background

Power tools are currently widely used in manual operations. Use the annular saw as the example, be comparatively typical direct current power tool, adopt the battery package power supply, require highly to the heat dissipation, the motor passes through drive mechanism drive saw bit and saws the operation, the inside controller that has in addition of instrument is controlled the motor, battery package, controller and motor can produce the heat at the course of the work, lead to the high temperature to influence the performance of instrument, and bring the potential safety hazard. In order to solve the above problems, the conventional electric circular saw is provided with a fan and air inlet and outlet holes to generate flowing cooling air flow for heat dissipation. However, in the conventional electric circular saw, air for the battery pack and the controller flows in the same air passage, and the air flow, which has previously cooled the battery pack and whose temperature is also increased, cools the controller again, lowering the cooling efficiency. Therefore, it is necessary to provide a power tool to solve the above problems.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to solve the problems that: a power tool is provided which is capable of efficiently cooling a battery pack and a controller and which is compact in structure.

In order to solve the problems, the technical scheme of the invention is as follows: the power tool includes: the motor drives the working head to work; a tool housing including a motor housing accommodating the motor and a grip housing; the fan is driven by the motor to rotate to generate cooling air flow, and the tool shell is provided with an air flow channel for the cooling air flow to pass through; the airflow channel comprises a first airflow channel and a second airflow channel, and the first airflow channel is independent of the second airflow channel; the tool shell is provided with a first cooling air port communicated with the first air flow channel and a second cooling air port communicated with the second air flow channel; a battery pack for supplying power to the motor, the battery pack comprising a housing and a battery cell contained in the housing, the housing comprising an air inlet and an air outlet, the air inlet and the air outlet communicating to form a battery pack airflow path, the battery pack airflow path communicating with the first airflow path when the battery pack is coupled to the tool housing; a controller for controlling the motor, the controller being at least partially disposed in the second airflow path.

The power tool disclosed by the invention is provided with two independent air flow channels for respectively cooling the battery pack and the controller, so that two air flows for cooling the battery pack and the controller are not influenced mutually, the battery pack and the controller can be fully cooled, the cooling efficiency is improved, and the requirement of cutting operation is met.

Preferably, the motor is an outer rotor type motor. The outer rotor type motor is adopted, so that the torque is large, the size is small, and the size of the tool can be further reduced while the cutting efficiency is ensured.

Preferably, the motor casing comprises a first end part close to the working head and a second end part far away from the working head, the fan is arranged in the first end part, an air outlet is formed in the first end part, and cooling air entering from the battery pack air flow passage enters the first air flow passage through the first cooling air inlet and is exhausted out of the tool casing through the air outlet; the cooling air flow entering from the second cooling air opening flows through the second air flow channel and is exhausted out of the tool shell from the air outlet.

Preferably, the motor casing includes a first end portion close to the working head and a second end portion far away from the working head, the fan is disposed in the first end portion, the second end portion is provided with an air inlet, a cooling airflow entering from the air inlet flows through the first airflow channel and the second airflow channel respectively, and the cooling airflow in the first airflow channel passes through the first cooling air inlet and then is discharged from the battery pack airflow channel; the cooling air flow in the second air flow channel passes through the controller and is exhausted by the second cooling air port.

Preferably, the motor casing includes a first end portion close to the working head and a second end portion far away from the working head, the fan is disposed in the second end portion, an air outlet is disposed at the second end portion, and the cooling air flowing from the battery pack air flow passage through the first cooling air inlet into the first air flow passage and the cooling air flowing from the second cooling air inlet into the second air flow passage pass through the motor and then are discharged out of the tool casing through the air outlet.

Preferably, a partition is provided in the tool housing, the partition dividing the airflow passage into the first airflow passage and the second airflow passage.

Preferably, a partition is disposed in the tool housing, the controller includes a circuit board, and a case supporting and at least partially enclosing the circuit board, and the partition and the case cooperate to divide the airflow channel into the first airflow channel and the second airflow channel.

Preferably, the controller includes a circuit board, and a box body supporting and at least partially surrounding the circuit board, and a partition is provided on the box body, and the partition cooperates with the box body to partition the airflow channel into the first airflow channel and the second airflow channel. Preferably, the holding shell comprises a holding part, an installation part connected with the holding part, and a connection part, wherein the installation part is used for installing the battery pack, and the airflow channel is at least partially located in the connection part.

Preferably, the first cooling tuyere is provided on the mounting portion, and the second cooling tuyere is provided on the connecting portion.

Preferably, a baffle plate is arranged between the first cooling air opening and the holding part. The baffle can prevent the air leakage between the holding part and the first air flow channel, so that the first air flow channel is relatively closed, and the heat dissipation of the battery pack is not influenced.

Preferably, the extension direction of the long side of the controller is perpendicular to the extension direction of the motor shaft of the motor.

Preferably, the partition is fixed to the inner surface of the tool housing, and extends from between the first cooling port and the second cooling port to the outside of the motor. Preferably, the mounting portion is located behind the holding portion in the cutting direction, and the holding portion is located above the connecting portion in the vertical direction.

Preferably, the controller is located in the connecting portion, and the controller is located between the motor and the battery pack in the cutting direction and below the holding portion in the vertical direction. The battery package is located the rear of the portion of gripping in the cutting direction, and the controller is located in the middle of motor and the battery package in the cutting direction, and the controller is located the portion of gripping below in vertical direction, and the reasonable overall arrangement space that has utilized makes the instrument whole compacter.

Preferably, the controller is provided with a heat sink which extends away from the first air flow passage.

Preferably, the controller is located in the connecting portion, and the controller is located between the motor and the battery pack in the cutting direction and below the holding portion in the vertical direction.

Preferably, the first air flow channel comprises an air flow channel disposed flush with the second air flow channel.

Preferably, the mounting portion is provided with a slide rail matched with the battery pack, and the extending direction of the slide rail is inclined relative to the extending direction of the connecting portion.

Preferably, the connecting portion is provided with an outer side plate parallel to the extending direction of the slide rail, and the second cooling air port is provided on the outer side plate.

Preferably, the installation part is provided with an inner side plate parallel to the extending direction of the slide rail, and the first cooling air port is arranged on the inner side plate.

Drawings

The invention will be further explained with reference to the drawings.

Fig. 1 is a perspective view of an electric power tool provided by the present invention.

Fig. 2 is a sectional view of the electric power tool shown in fig. 1.

Fig. 3 is a schematic view of the air duct of the power tool shown in fig. 1 with a portion of the grip housing removed.

Fig. 4 is a schematic view of the grip housing of the power tool of fig. 1 shown in half-divided.

Fig. 5 is a cross-sectional view of a controller of the power tool of fig. 1.

Fig. 6 is a partial cross-sectional view of the power tool of fig. 1.

FIG. 7 is a schematic view of an air duct with a portion of the grip housing removed in accordance with another embodiment of the power tool.

FIG. 8 is a schematic view of an air duct with a portion of the grip housing removed in accordance with another embodiment of the power tool.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the present embodiment, the technical solution of the present invention is described by taking an electric circular saw as an example, but the power tool of the present invention is not limited to the electric circular saw, and may be other electric tools powered by a battery pack, such as a jigsaw.

In order to facilitate understanding of the present application, in this specification, a vertical upward direction when the reader faces fig. 1 is referred to as an upper side of the electric circular saw 100, and a vertical downward direction is referred to as a lower side of the electric circular saw 100.

It should be noted that the definitions of the directions in the present specification are only for convenience of description of the technical solution of the present application, and do not limit the directions of the electric circular saw of the embodiments of the present application in other scenarios, including but not limited to use, test, transportation, and manufacture, which may cause the orientation of the components to be reversed or the positions of the components to be changed. In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As shown in fig. 1 and 2, the power tool is exemplified by an electric circular saw 100. The electric circular saw includes a motor 10, a tool case 20 accommodating the motor 10, and a working head 11 rotated by the motor 10 to perform a cutting operation. The working head 11 is here a saw blade, which is coupled to a drive shaft 12. Since the saw blade 11 has a certain thickness, in the following description, the saw blade 11 is ideally regarded as having a very small thickness, and the plane on which the saw blade 11 is located is defined as the plane of the saw blade. The cutting direction F is defined as the advancing direction of the saw blade 11 when the electric circular saw 100 shown in fig. 1 is normally operated.

The electric circular saw 100 includes a fixed guard 13 attached to the tool case 20 for covering an upper half portion of the saw blade 11, and a movable guard 14 covering a lower half portion of the saw blade 11 and rotatable coaxially with the driving shaft 12 of the saw blade 11. The electric circular saw 100 further includes a base plate 15 connected to the fixed guard 13, and having a bottom surface 151 slidable on a surface of a material to be cut, such as wood, and a blade groove through which the saw blade 11 can protrude downward from the bottom surface 151 to cut the workpiece.

The fixed shield 13 is pivotally connected to the base plate 15. The fixed guard 13 rotates relative to the base plate 15 about the depth-of-cut axis X1 to vary the distance the blade 11 extends from the bottom surface 151 for varying the depth of the cut. The depth cut axis X1 is parallel to the axis X2 of the drive shaft 12. The electric circular saw 100 is further provided with a depth lock mechanism 16 for locking the relative position of the fixed guard 13 with respect to the base plate 15, and also locking the cutting depth of the saw blade 11.

The fixed guard 13 is rotated relative to the base plate 15 about a miter cut axis (not shown) to change the angle of inclination of the saw blade 11 relative to the bottom surface 151 to make a miter cut. The chamfer axis is perpendicular to the cut-depth axis X1 and parallel to the bottom surface 151. The electric circular saw 100 is further provided with a bevel lock mechanism 18 for fixing the relative position of the guard 13 with respect to the base plate 15, and also locking the inclination angle of the saw blade 11.

The tool housing 20 includes a motor case 21 for housing the motor 10, and a grip housing 24 connected to the motor case 21. Wherein, the motor casing 21 is fixedly connected with the fixed shield 13. The motor 10 includes a motor shaft 101, and the motor shaft 101 is supported inside the motor case 21 by a bearing 103. The axis 102 of the motor shaft 101 is arranged perpendicular to the plane of the saw blade and parallel to the axis X2 of the drive shaft 12. The end of the motor 10 close to the saw blade 11 is defined as a front end of the motor, and the end far from the saw blade 11 is defined as a rear end of the motor, in this embodiment, the fan 16 is located at the rear end of the motor and fixed opposite to the motor shaft 101, and is driven by the motor 10 to rotate to generate a cooling air flow. In the present embodiment, the fan 16 is a centrifugal fan, and the volume of the tool can be reduced as much as possible while ensuring a cooling effect.

The transmission mechanism is located between the motor 10 and the driving shaft 12, and is used for transmitting the power of the motor 10 to the saw blade 11 so as to drive the saw blade 11 to rotate. The transmission mechanism can be gear transmission, worm gear and worm, belt transmission and the like. In the present embodiment, the transmission mechanism is a gear transmission mechanism including a pinion gear provided on the motor shaft 101 and a bull gear provided on the drive shaft 12.

The motor 10 is an external rotor brushless motor, and includes a stator 107 fixed relative to the motor housing 21 and a rotor 105 rotating around the periphery of the stator 107, the rotor 105 is in the shape of a sleeve with through holes at both ends, the periphery of the rear end is fixedly connected with the fan blades of the fan 16, the fan 16 is fixedly connected with the motor shaft 101, and therefore the external rotor 105 is fixedly connected with the motor shaft 101 through the fan 16. In this way, the arrangement of the motor 10 and the fan 16 can be made more compact without requiring an additional rear end side wall of the rotor 105 to be connected to the motor shaft 101. In addition, the fan 16 may be made of a rigid metal material, which can ensure connection rigidity and has a better heat dissipation effect. And the outer rotor motor has the advantages of large torque and small volume, and can further reduce the volume of the tool when being applied to the electric circular saw. Of course, the motor may also be an internal rotor motor, and the fan may also be driven to rotate to generate cooling airflow.

The grip case 24 includes a grip portion 23 for operating the grip, and a connecting portion 27 located below the grip portion 23. The grip portion 23 is provided with a switch unit 231 for controlling the start of the motor. The connecting portion 27 extends lengthwise, generally parallel to the plane of the saw blade, and perpendicular to the axis 102 of the motor shaft 101. In the present embodiment, the electric circular saw is a direct current circular saw, and includes a battery pack 30 for supplying power to the motor 10. The rear side of the grip portion 23 is provided with a mounting portion 25 for mounting a battery pack. The mounting portion 25 is provided with a slide rail (not shown), the battery pack 10 is slidably coupled to the grip housing 24 through the slide rail, and the extending direction of the slide rail is inclined with respect to the extending direction of the connecting portion, so that the overall size can be reduced. Of course, the electric circular saw may be powered by ac power instead of the battery pack. The grip portion 23 may be integrated into the tool housing 20 or connected thereto as a separate element.

Referring back to fig. 3, in order to control the brushless motor 10, the electric circular saw further includes a controller 40. The controller 40 includes at least a drive circuit including a switching element for switching power supplied to the brushless motor and a control circuit for controlling the drive circuit. The tool housing 20 is also formed with an air flow passage through which a cooling air flow passes in order to cool the battery pack 30 and the controller 40. Specifically, the air flow passages include a first air flow passage 71 and a second air flow passage 73. Wherein the first air flow channel 71 is independent of the second air flow channel 73; the first air flow path 71 serves as a cooling path for cooling the battery pack 20, and the second air flow path 73 serves as a cooling path for cooling the controller 40. The tool shell 20 is provided with a first cooling air port 61 and a second cooling air port 63 which are communicated with the outside, wherein the first cooling air port 61 is communicated with a first air flow channel 71; the second cooling tuyere 63 communicates with the second air flow passage 73. In the present embodiment, the first and second

cooling air ports

61 and 63 are air inlets into which cooling air flows. The air flow entering from the first cooling port 61 flows toward the fan 16 through the first air flow passage 71 in the direction of arrow "a", and the air flow entering from the second cooling port 63 flows toward the fan 16 through the second air flow passage 73 in the direction of arrow "B". In the connecting portion of the grip housing 24, the cooling air flow passing through the first air flow passage 71 does not mix with the cooling air flow passing through the second air flow passage 73. I.e., the air flow cooled through the battery pack 30 does not pass through the controller 40; the air flow that has cooled the controller 40 does not pass through the battery pack 30. That is, both the battery pack 30 and the cooling controller 40 are cooled by cold air, and thus, both the battery pack 30 and the controller 40 can be sufficiently cooled, thereby improving the cooling effect and efficiency. The first cooling air port 61 and the second cooling air port 63 may be slit-shaped or hole-shaped, and as long as they can communicate with the outside cold air, their shapes and numbers are not specifically limited, and in order to prevent the foreign matter from being sucked, the air inlet may be provided with a dust screen or the like, or may be designed as a floating-submerged air inlet.

As shown in fig. 3 and 4, the first cooling tuyere 61 is provided on the mounting portion 25, and the first and second

air flow passages

71 and 73 are provided on the mounting portion 25 and the connection portion 27. And the first air flow path 71 includes an air flow path arranged flush with the second air flow path 73, the space of the connection portion 27 can be effectively utilized by such an arrangement. The mounting portion 25 is provided with an inner plate 62 substantially parallel to the extending direction of the slide rail, and the first cooling air port 61 is provided in the inner plate 62. When the battery pack 30 is attached to the mounting portion 25, the battery pack cooling airflow takes heat of the battery pack 30 through the first airflow passage 71 by the fan 16.

Specifically, the battery pack 30 includes a plurality of battery cells 31 and a casing 33 for accommodating the battery cells, and the casing 33 is further provided with an air inlet 331 and an air outlet 333. The air inlet 331 and the air outlet 333 are communicated to form a battery pack air flow passage (not numbered). Here, the battery pack airflow path includes a gap between the battery cells 31, and a gap between the battery cells 31 and the case 33. When the battery pack 30 is connected to the mounting portion 25, the air outlet 333 is communicated with the first cooling air inlet 61, and the battery pack cooling air flows into the casing 33 through the air inlet 331, flows over the surfaces of the battery cells 31, flows out through the air outlet 333, flows through the first cooling air inlet 61, and enters the first air flow channel 71 in the tool housing 20, so that the heat of the battery pack 30 is dissipated under the action of the battery pack cooling air flow.

In order to enhance the heat dissipation effect of the battery pack 30, it is also conceivable to provide a fan for generating an air flow between the air inlet 331 and the air outlet 333, and a battery pack motor is provided in the housing 33 for driving the fan to rotate.

The second cooling tuyere 63 is provided at the connection portion 27, and the controller 40 is disposed in the second air flow passage 73. In the present embodiment, the connecting portion 27 is provided with an outer plate 64 parallel to the extending direction of the slide rail, and the second cooling air port 63 is provided in the outer plate 64. Of course, the second cooling air inlet is located at the end of the connecting portion 27 far from the fan 16 and close to the controller 40, so that the air flow can be ensured to flow through the whole controller, and the cooling efficiency can be improved. Of course, in order to increase the intake air volume, a plurality of second cooling air ports may be provided on the connection portion 27, for example, the second cooling air ports may be provided on the upper portion of the connection portion 27 or on both sides of the connection portion 27.

As shown in fig. 5, the controller 40 includes a circuit board 41, a case 45 supporting and surrounding the circuit board, and a heat sink 43 mounted on the circuit board 41 to extend substantially perpendicular to the case 45. In particular, the casing 45 is thermally nonconductive, such as plastic. The main heating elements on the circuit board 41, such as MOS transistors, are connected to the heat sink 43 through the heat conductive silicone 47, so as to ensure that the heat generated by the circuit board is conducted to the heat sink 43, and the heat insulating sealing potting compound 49 is filled between the circuit board 41 and the box 45 and between the heat sink 43 and the box 45, so that the heat is not transferred to the box 45.

As shown in fig. 3, 4 and 6, the case 45 of the controller 40 is supported and fixed by the rib 29 inside the tool housing 20, and is located in the second air flow path 73. The long side 451 of the case 45 extends in a direction substantially perpendicular to the axial direction of the motor shaft 101, and the long side 451 is substantially parallel to the extending direction of the connecting portion 27. The controller 40 is located between the motor 10 and the battery pack 30 in the cutting direction F and between the grip portion 23 and the bottom plate 15 in the vertical direction, and the controller 40 is located at a height position between the grip portion 23 and the bottom plate 15 because the controller 40 does not affect the grasping operation of the operator at this position. The heat sink 43 on the controller 40 is approximately perpendicular to the box body 45 and extends towards the direction of the bottom plate 15, and the second cooling air port 63 is arranged at one end of the controller 40 far away from the fan 16 and close to the heat sink 43, so that the largest area of cooling air flow can be ensured to contact with the heat sink 43, and the cooling efficiency is improved.

As shown in fig. 3 and 4, the electric circular saw 100 includes a partition 50, and the partition 50 cooperates with the connecting portion 27 to partition the air flow passage into a first air flow passage 71 and a second air flow passage 73. In the present embodiment, the partition 50 extends from between the first cooling air port 61 and the second cooling air port 63 to the motor case 21 through above the controller case 45. The motor casing 21 is provided with a through hole 211, and the cooling air flows into the through hole 211 and enters the motor casing 21 after passing through the first air flow channel 71 and the second air flow channel 73 respectively. The partition 50 extends from the mounting portion 25 to the through hole 211 of the motor housing 21.

The partition 50 may be an extended rib integrally formed with the inner surface of the tool housing 20 or a partition plate fixed to and closely fitted to the inner surface of the tool housing 20, although the partition 50 is preferably made of a non-heat conductive material. The partition 50 divides the air flow passage into upper and lower portions, i.e., a first air flow passage 71 for cooling the battery pack 30 is provided above, and a second air flow passage 73 for cooling the controller 40 is provided below.

As shown in fig. 4, in the present embodiment, the grip portion 23, the mounting portion 25, and the connecting portion 27 are integrated as a single unit, and are of a half-shell structure that is split left and right, and the partition 50 is a rib extending from the inner surface of the tool housing 20, and is formed in half of each of the two half shells, and when the two half shells are assembled together, the two part partitions are joined together and function to partition the air flow. This arrangement facilitates the removal and installation of the tool and the replacement of internal parts. It should be noted that, in the connecting portion 27 of the controller 40, the switch component 231 is disposed on the holding portion 23, and the switch component 231 is electrically connected to the controller 40, which inevitably requires the opening 51 of the partition 50 for passing the power supply. In this case, it is necessary to ensure that the opening 51 is as small as possible and that the sealing can be performed by means of sponge or sealant. In order to prevent the holding portion 23 and the first air flow channel 71 from being mixed with wind, the heat dissipation of the battery pack 30 is affected. The baffle 53 is disposed between the first cooling air inlet 61 and the holding portion 23, and the baffle 23 can be formed in the same manner and made of the same material as the partition 50, which is not described in detail herein. Of course, the baffle 53 is also provided with an opening through which the power supply line passes. However, the opening is as small as possible, or the first air flow channel 71 is sealed by sponge or sealant, and the like, so as to ensure that the first air flow channel 71 is relatively closed.

The motor housing 21 includes a first end portion close to the saw blade 11 (partially housed in the fixed guard 13) and a second end portion remote from the saw blade 11. The air outlet 60 is provided at a second end portion of the motor casing 21, i.e., radially outward of the fan 16. Of course, the fan may also be an axial flow fan, and the air outlet may be disposed in the axial direction of the fan instead of being disposed radially outside the fan. The cooling air flows in the first air flow channel 71 and the second air flow channel 73 enter the motor casing 21 through the through hole 211, and are merged in the motor casing 21 to cool the motor 10. Specifically, the cooling air flows through the gap between the rotor 105 and the stator 107 to dissipate heat from the motor 10. And then is discharged out of the tool housing 20 through the air outlet 60 of the motor housing 21.

Of course, a third air inlet (not shown) may be additionally provided on the motor casing 21, and the cold air entering from the third air inlet is used for cooling the motor 10. In order to improve the cooling efficiency, an airflow guiding device, such as a volute, may be added at the periphery of the fan 16 to guide the air flow, so as to improve the wind outlet efficiency, thereby enhancing the cooling effect.

Since the first air flow path 71 and the second air flow path 73 are spaced apart from each other, they are independent of each other. The first air flow path 71 serves as a cooling path for cooling the battery pack 30, and the second air flow path 73 serves as a cooling path for cooling the controller 40. Therefore, it is possible to avoid the situation where the airflow having cooled one of the battery pack 30 or the controller 40 affects the other of the battery pack 30 or the controller 40, and both can be sufficiently cooled, thereby improving the cooling efficiency and preventing machine malfunction due to excessive temperature.

Further, the first air flow channel 71 and the second air flow channel 73 are formed only by the partition; no other components are involved, and therefore the first air flow path 71 and the second air flow path 73 are formed at low cost and with a simple structure.

Further, the controller 40 is located between the motor 10 and the battery pack 30 in the machine direction, is located between the grip 23 and the base plate 15 in the vertical direction, and has a long side 451 extending perpendicular to the axis 102 of the motor shaft 101. Through the layout mode, the space layout of the whole tool is reasonably utilized, the grasping operation structure of an operator is not influenced, and meanwhile, the cooling effect of the controller 40 is ensured.

Further, both the air flow in the first air flow path 71 and the air flow in the second air flow path 73 may be generated by one fan 16. Therefore, it is not necessary to provide separate fans for the respective air passages in the tool, and the size increase of the electric circular saw can be avoided, and the cost for providing an additional fan can be reduced.

As shown in fig. 7, according to another embodiment of the present invention, an electric circular saw 100a is provided. The electric circular saw 100 according to the first embodiment includes a tool case 20, and the tool case 20 includes a motor case 21 for housing a motor (not shown) and a grip case 24 connected to the motor case 21. The fan (not shown) is located at the rear end of the motor, and an air outlet is provided at a second end of the motor housing 21 away from the saw blade 11. The air outlet is arranged at the radial outer side of the fan. Two separate air flow passages, a first air flow passage 71 and a second air flow passage 73, are provided in the grip housing 24 for cooling the battery pack and the controller 40, respectively.

In this embodiment, the first cooling air port 61 and the second cooling air port 63 are air inlets, and the specific structure is basically the same as that of the first embodiment, and will not be described herein again. The difference is in the partition between the first air flow channel 71 and the second air flow channel 73. In the present embodiment, the partition 50a extends to the end of the case 45 of the controller 40 and abuts closely against the case 45, and the partition 50a and the case 45 work together to divide the air flow passage into two. Here, the partition 50a may be an extended rib integrally formed with the inner surface of the tool case 20, or a partition plate fixed to and closely fitted with the inner surface of the tool case 20; also, the separator 50a is preferably made of a material that is not thermally conductive.

Under the combined action of the partition 50 and the box 45, the battery pack cooling airflow flows in the first airflow passage 71 in the direction of arrow "a", flows over the partition 50 and the box 45, and then enters the motor case 21. The battery pack cooling air flow flows in the first air flow passage 71 in the direction of arrow "a", flows over the partition 50 and the box 45, and then enters the motor case 21. The air flow entering from the second cooling air port 63 flows through the partition 50 and the lower side of the box body 45 through the second air flow passage 73 in the direction of arrow "B", cools the controller 40, and then enters the motor case 21. In this process, since the case 45 of the controller is not thermally conductive, the heat in the battery pack cooling air flow does not affect the controller 40, and vice versa, thereby achieving mutual independence of the two air flow paths.

In this embodiment, the case 45 of the controller may preferably abut against the outside of the motor case 21. It is of course also possible to allow a gap between the box 45 and the motor housing 21, but this gap should not be too large, preferably not more than 1cm, in which case the cooling air flows from the first air flow channel 71 and the second air flow channel 73 will enter the motor housing 21 directly under a greater pressure without interfering with each other, since the gap is closer to the fan 16, i.e. closer to the centre of negative pressure of the fan, where the fan has a greater capacity to draw in air flow.

Of course, the box body can also be provided with a separator which is matched with the box body to divide the airflow channel into a first airflow channel and a second airflow channel. Here, the partition may be integrally formed with the case; or a partition board fixed on the box body and tightly matched with the box body; also, the partition and the case are preferably made of a material that is not thermally conductive.

As shown in fig. 8, according to another embodiment of the present invention, an electric circular saw 100b is provided. The electric circular saw 100 according to the first embodiment includes a tool case 20, and the tool case 20 includes a motor case 21 for housing a motor (not shown) and a grip case 24 connected to the motor case 21. Two independent air flow passages, a first air flow passage 71 and a second air flow passage 73, are provided in the grip housing 24 for cooling the battery pack 30 and the controller 40, respectively.

In the present embodiment, the fan (not shown) is located at the front end of the motor, and the air inlet 80b is provided at the second end of the motor housing 21 away from the saw blade 11. The air inlet 80b may be disposed on an end surface of the motor housing 21 away from the saw blade 11 and/or a circumferential surface of the motor housing 21, so as to increase an air inlet amount.

In the present embodiment, the first cooling air port 61b and the second cooling air port 63b are air outlets, wherein the first cooling air port 61 is communicated with the battery pack air flow passage through an air inlet (not shown) on the battery pack. The air flow from the air inlet 80b flows through the flow motor and then enters the first air flow channel 71 and the second air flow channel 73, respectively. The air flow entering the first air flow channel 71 flows through the first cooling air inlet 61b along the direction of arrow "C" and then enters the battery pack air flow channel, cools the battery pack 30, and is discharged from the air outlet 333b of the battery pack 30. The air flow entering the second air flow channel 73 flows through the controller 40 in the direction of arrow "D" to cool the controller 40 and finally exits the tool housing 20 through the second cooling air port 63 b.

In this embodiment, although the cooling airflow for cooling the battery pack 30 and the controller 40 is the airflow after cooling the motor. However, because the rising temperature of the motor is not too high during the operation, the temperature of the battery pack 30 and the controller 40 is high, and particularly the temperature of the controller 40 can rise to 70 ℃ and 80 ℃; in addition, the air inlet 80b can be arranged on the end surface and the peripheral surface of the motor casing 21 at the second end part of the motor casing 21 far away from the saw blade 11, and the air inlet amount is large. Also, the cooling airflow of the first airflow path 71 is relatively independent of the cooling airflow through the second airflow path 73, and both the battery pack 30 and the controller 40 can be sufficiently cooled. Therefore, even if the battery pack 30 and the controller 40 are cooled by the airflow after cooling the motor, the cooling effect is not affected.

In another embodiment, the fan is located at the front end of the motor. An air outlet is arranged at the first end part of the motor shell close to the saw blade. The air outlet is positioned at the radial outer side of the fan. The second end of the motor casing is provided with an air inlet, the air inlet can be arranged on the end face of the motor casing far away from the saw blade and/or the circumferential face of the motor casing, cooling gas enters from the air inlet arranged at the second end under the action of the fan, flows through the motor, cools the motor, and is discharged out of the tool casing through the air outlet on the outer side of the fan. In this embodiment, the cooling air flow in the first air flow passage and the second air flow passage enters the motor case through the through-hole, but unlike the first embodiment, the cooling air flow entering the motor case through the through-hole does not need to flow through the motor but is directly discharged out of the tool case through the air outlet outside the fan. In this way, two independent air flow channels, namely a first air flow channel and a second air flow channel, are also arranged in the holding shell and are respectively used for cooling the battery pack and the controller. Further, a cooling air flow enters the motor housing via the second end of the motor housing for cooling the motor. That is to say, what cool off battery package, cooling controller and cooling motor is cold air, so set up, motor, battery package and controller all can be fully cooled down, have improved cooling effect and efficiency.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for those skilled in the art, variations and modifications can be made without departing from the spirit of the present invention, and it is within the scope of the present invention that the functions be achieved by the same or similar to the present invention.

Claims

1. A power tool, characterized by: the power tool includes:

the motor drives the working head to work;

a tool housing including a motor housing accommodating the motor and a grip housing;

the fan is driven by the motor to rotate to generate cooling air flow, and the tool shell is provided with an air flow channel for the cooling air flow to pass through; the airflow channel comprises a first airflow channel and a second airflow channel, and the first airflow channel is independent of the second airflow channel; the tool shell is provided with a first cooling air port communicated with the first air flow channel and a second cooling air port communicated with the second air flow channel;

a battery pack for supplying power to the motor, the battery pack comprising a housing and a battery cell contained in the housing, the housing comprising an air inlet and an air outlet, the air inlet and the air outlet communicating to form a battery pack airflow path, the battery pack airflow path communicating with the first airflow path when the battery pack is coupled to the tool housing;

a controller for controlling the motor, the controller being at least partially disposed in the second airflow path.

2. The power tool of claim 1, wherein: the motor is an outer rotor type motor.

3. The power tool of claim 1, wherein: the motor shell comprises a first end part close to the working head and a second end part far away from the working head, the fan is arranged in the first end part, an air outlet is formed in the first end part, cooling air entering from the battery pack air flow passage enters the first air flow passage through the first cooling air inlet and is discharged out of the tool shell through the air outlet; the cooling air flow entering from the second cooling air opening flows through the second air flow channel and is exhausted out of the tool shell from the air outlet.

4. The power tool of claim 1, wherein: the motor shell comprises a first end part close to the working head and a second end part far away from the working head, the fan is arranged in the first end part, the second end part is provided with an air inlet, cooling airflow entering from the air inlet respectively flows through the first airflow channel and the second airflow channel, and the cooling airflow in the first airflow channel passes through the first cooling air inlet and then is discharged from the battery pack airflow channel; the cooling air flow in the second air flow channel passes through the controller and is exhausted by the second cooling air port.

5. The power tool of claim 1, wherein: the motor shell comprises a first end part close to the working head and a second end part far away from the working head, the fan is arranged in the second end part, an air outlet is formed in the second end part, and cooling air flow which flows through the first cooling air port from the battery pack air flow channel and enters the first air flow channel and cooling air flow which flows through the second cooling air port and enters the second air flow channel passes through the motor and then is discharged out of the tool shell through the air outlet.

6. The power tool of claim 1, wherein: a divider is disposed within the tool housing, the divider dividing the airflow channel into the first airflow channel and the second airflow channel.

7. The power tool of claim 1, wherein: a divider is disposed within the tool housing, the controller includes a circuit board, a case supporting and at least partially enclosing the circuit board, the divider and the case coacting to divide the airflow channel into the first airflow channel and the second airflow channel.

8. The power tool of claim 1, wherein: the controller comprises a circuit board and a box body which supports and at least partially surrounds the circuit board, wherein a partition is arranged on the box body, and the partition is matched with the box body to divide the airflow channel into the first airflow channel and the second airflow channel.

9. The power tool of claim 1, wherein: the holding shell comprises a holding part, an installation part and a connecting part, wherein the installation part is connected with the holding part, the battery pack is installed on the installation part, and at least part of the airflow channel is located in the connecting part.

10. The power tool of claim 9, wherein: and a baffle is arranged between the first cooling air opening and the holding part.