CN213693376U - Hand-held electric tool - Google Patents

Abstract

The utility model relates to a hand-held electric tool, which comprises a head shell and a holding part, wherein the holding part is provided with a first airflow inlet, and the head shell is provided with an airflow outlet; the motor is accommodated in the head shell and comprises a motor shell and an output shaft, the motor shell is provided with a head end and a tail end, the output shaft extends out of the head end, the motor shell is provided with an air inlet and an air outlet, the air inlet comprises a first air inlet arranged at the head end and a second air inlet arranged at the tail end, and the air outlet is arranged between the head end and the tail end; a fan; when the fan is driven rotatoryly by the output shaft, wind divides into two the tunnel after getting into from first air current inlet, and first way gets into inside the motor from the first air intake of the head end of motor casing, cools off the motor is inside, and the second way cools off the motor from the motor outside earlier, then gets into inside the motor from the second air intake of the tail end of motor casing again, cools off the motor from the motor is inside, so cool off the motor from inside and outside the motor, and the cooling effect is better.

Description

Hand-held electric tool

Technical Field

The utility model relates to an electric tool technical field especially relates to a hand-held type electric tool.

Background

The hand-held electric tool drives the working head to work by using the motor, and the motor can generate a large amount of heat in the working process and needs to be effectively cooled. In the traditional technology, one solution is to add a fan between the reduction box and the motor, and the casing is provided with an air inlet and an air outlet. However, in the working process, the air inlet is easy to block, so that the air inlet volume is reduced, and the machine is easy to burn.

SUMMERY OF THE UTILITY MODEL

In view of the above, there is a need for a hand-held power tool that can ensure a cooling effect of a motor.

A hand-held power tool comprising: the shell comprises a head shell and a holding part arranged at an angle with the head shell, wherein the holding part is provided with a first airflow inlet, and the head shell is provided with an airflow outlet; the motor is accommodated in the head shell and comprises a motor shell and an output shaft, the motor shell is provided with a head end and a tail end which are arranged oppositely, the output shaft extends out of the head end, the motor shell is provided with an air inlet and an air outlet, the air inlet comprises a first air inlet arranged at the head end and a second air inlet arranged at the tail end, and the air outlet is arranged between the head end and the tail end; the fan is connected to the output shaft, and when the fan is driven by the output shaft to rotate, a first cooling air path which enters from the first air inlet, enters the motor through the first air inlet, flows out of the motor from the air outlet and is discharged out of the head shell from the air outlet is formed in the shell; and the second heat dissipation air path enters from the first air inlet, passes through between the motor shell and the head shell, enters the motor through the second air inlet, flows out of the motor from the air outlet and is discharged out of the head shell from the air outlet.

In the handheld electric tool, the fan generates negative pressure in the motor shell after rotating, air enters from the first air inlet and then is divided into two paths, and the first path enters the motor from the first air inlet at the head end of the motor shell to cool the interior of the motor; the second way cools off the motor from the motor outside earlier, then gets into the motor from the second air intake of the tail end of motor casing inside again, cools off the motor from the motor is inside, so cool off the motor respectively from inside and outside the motor, the cooling effect is better. In addition, the first airflow inlet is arranged on the holding part and is far away from the working head, namely, the first airflow inlet is far away from a severe working environment area, so that the blockage situation is not easy to occur in the working process, and the burn-in phenomenon is avoided.

In one embodiment, the handheld electric tool further comprises a transmission mechanism and a partition, the transmission mechanism is accommodated in the head shell, the partition is fixed in the head shell and separates the first air inlet from the transmission mechanism, a vent hole communicating the first air inlet and the first air inlet is formed in the partition, and the output shaft penetrates through the partition and is connected with the transmission mechanism.

In one embodiment, the spacer includes a bottom plate and a support ring connected to the bottom plate, wherein the bottom plate separates the first air inlet from the transmission mechanism, the bottom plate defines a first bearing hole engaged with the output shaft, the support ring is disposed around the first bearing hole, the support ring defines the ventilation hole, the head end is embedded in the support ring, and an outer wall of the motor casing is in sealing engagement with an inner wall of the support ring.

In one embodiment, the head end is spaced from the base plate, and the first air inlet is located on the side of the vent hole far away from the base plate in the axial direction of the output shaft.

In one embodiment, the transmission mechanism is supported on the base plate.

In one embodiment, the transmission mechanism includes a first gear, a second gear, and a transmission shaft, the first gear is engaged with the second gear, the first gear is fixed to the output shaft, the second gear is fixed to the transmission shaft, and one end of the transmission shaft is supported on the bottom plate.

In one embodiment, the bottom plate is formed with a second bearing hole, and one end of the transmission shaft is supported in the second bearing hole through a bearing.

In one embodiment, the motor includes a carbon brush, and the carbon brush is located between the air outlet and the second air inlet in an axial direction of the output shaft.

In one embodiment, a second airflow inlet is formed in the head casing at a position close to the second air inlet, and when the fan is driven to rotate by the output shaft, a third cooling air path is formed in the casing, which enters from the second airflow inlet, enters the motor through the second air inlet, flows out of the motor from the air outlet, and is discharged out of the head casing from the airflow outlet.

In one embodiment, the fan is disposed inside the motor casing and located near the air outlet.

Drawings

Fig. 1 is a schematic structural view of a handheld electric tool according to an embodiment of the present invention.

Fig. 2 is a partial sectional view of a hand-held power tool according to an embodiment of the present invention.

Fig. 3 is a partial cross-sectional view of another angle of the hand-held power tool according to an embodiment of the present invention.

Fig. 4 is a side view of a reduction gear box bracket in a hand-held electric tool according to an embodiment of the present invention.

Fig. 5 is an attached view of a reduction gear box bracket in a hand-held electric tool according to an embodiment of the present invention.

The relevant elements in the figures are numbered correspondingly as follows:

100. a hand-held power tool; 10. a housing; 110. a head shell; 111. an airflow outlet; 112. a switching part; 113. a second gas flow inlet; 120. a grip portion; 121. a first gas flow inlet; 122. an air duct; 123. A handle; 130. a safety shield; 20. a motor; 210. a motor housing; 211. a head end; 212. a tail end; 213. a first air inlet; 214. a second air inlet; 215. an air outlet; 220. an output shaft; 230. a fan; 240. A working head; 250. a carbon brush; 30. a separation frame; 310. a base plate; 311. a first bearing bore; 320. a support ring; 321. a vent hole; 330. a connecting portion; 331. a through hole; 410. a first gear; 420. a second gear; 430. a drive shaft; 431. a first positioning bearing; 432. a second positioning bearing.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The following describes a preferred embodiment of the hand-held power tool 100 according to the present invention with reference to the drawings. In an embodiment of the present invention, the hand-held power tool 100 is specifically a lawn mower. Furthermore, the type of the hand-held electric tool is not limited to a lawnmower, and may be, for example, a chain saw, a pruner, a lawnmower, a high-pressure cleaner, or the like.

Referring to fig. 1 to 3, a handheld electric tool 100 according to an embodiment of the present invention is illustrated, including a housing 10 and a motor 20 accommodated in the housing 10. The casing 10 includes a head casing 110 and a holding portion 120 disposed at an angle to the head casing 110, wherein the holding portion 120 is provided with a first airflow inlet 121, and the head casing 110 is provided with an airflow outlet 111.

The motor 20 is accommodated in the head housing 110, the motor 20 includes a motor housing 210, an output shaft 220 and a fan 230, wherein the motor housing 210 has a head end 211 and a tail end 212 which are oppositely arranged, the output shaft 220 extends out of the head end 211, an air inlet and an air outlet 215 are formed on the motor housing 210, the air inlet includes a first air inlet 213 arranged at the head end 211 and a second air inlet 214 arranged at the tail end 212, and the air outlet 215 is arranged between the head end 211 and the tail end 212. The output shaft 220 of the motor 20 is connected with a transmission mechanism, and the transmission mechanism is connected with the working head 240. The output shaft 220 may also be directly connected to a working head 240, the working head 240 being in particular a grass cutting head having a cutting element in particular a grass cutting cord for cutting grass. The cutting element may also be a cutting blade. The working head 240 may also be a grinding blade for grinding, a polishing blade for polishing, or the like. In practice, different operating modes are achieved by different working heads 240. The safety shield 130 is fixed on the outer side of the working head 240, and is in a posture of semi-surrounding the working head 240, so that the safety during working is improved. The outlet 215 is disposed on the motor housing 210 near the airflow outlet 111 of the head housing 110, so that the air flowing out of the outlet 215 can be quickly discharged to the outside of the housing 10 through the airflow outlet 111.

The fan 230 is connected to the output shaft 220, which is embodied as a centrifugal fan, for generating an air flow entering from the outside of the casing 10. Specifically, the fan 230 is disposed inside the motor casing 210 and located near the air outlet 215. The fan 230 is rotated by the power supplied from the motor 20, and when the fan 230 rotates, a negative pressure is formed at the first air inlet 121, so that the wind enters the inside of the grip 120 from the first air inlet 121.

The grip 120 specifically includes an air inlet pipe 122 connected to the head housing 110 and a handle 123, wherein one end of the air inlet pipe 122 is connected to the head housing 110, and the other end is connected to the handle 123. The first air inlet 121 is formed in the wall of the air inlet duct 122 and may be formed in the handle 123. Specifically, an adapter 112 connected to the head housing 110 is provided at one side of the head housing 110. The air inlet duct 122 is mounted on the transition section 112. The adapter 112 and the head shell 110 are arranged at an acute angle, so that the air inlet pipe 122 and the head shell 110 are arranged at an acute angle, an operator can conveniently grasp the handle 123, and the device conforms to ergonomics. The axis of the air inlet duct 122 of the grip 120 is at 45 degrees to the axis of the output shaft 220, but may be at other angles, such as perpendicular to each other. The air inlet pipe 122 and the adapter 112 are detachably connected, so that a user can replace the holding part 120 with a suitable length as required. The air inlet duct 122 is embodied as a hollow aluminum tube. The number of the first air inlet 121 is not limited, and for example, when the first air inlet 121 is opened in the air inlet duct 122, a plurality of the first air inlets 121 may be arranged side by side along the axial direction of the air inlet duct 122. The shape of the first airflow inlet 121 is not limited and may be circular, elliptical, rectangular, etc.

Further, as shown in fig. 1, an auxiliary handle 124 is connected to the air inlet pipe 122. When the user holds the work, one hand holds the handle 123 and the other hand holds the auxiliary handle 124.

When the fan 230 is driven by the output shaft 220 to rotate, a first cooling air path S1 is formed in the housing 10, which enters from the first air inlet 121, enters the motor 20 through the first air inlet 213, flows out of the motor 20 from the air outlet 215, and is discharged out of the head housing 110 from the air outlet 111; and a second cooling air path S2 entering from the first air inlet 121, passing between the motor housing 210 and the head housing 110, entering the interior of the motor 20 through the second air inlet 214, exiting the motor 20 from the air outlet 215, and exiting the head housing 110 through the air outlet 111.

Above-mentioned hand-held electric tool 100, fan rotatory back produces the negative pressure in the casing, wind divides into two the tunnel after getting into from first air current import 121, first the tunnel gets into inside motor 20 from first air intake 213 of head end 211 of motor casing 210, cool off inside motor 20, the second tunnel cools off motor 20 from the motor 20 outside earlier, then get into inside motor 20 from second air intake 214 of tail end 212 of motor casing 210 again, cool off from the inside wire winding to the rotor of motor 20, so cool off motor 20 from inside and outside of motor 20, the cooling effect is better. In addition, the first airflow inlet 121 is disposed on the holding portion 120 and is far away from the working head 240, i.e., away from a severe working environment area, so that a blockage situation is not likely to occur during a working process, and a burn-out phenomenon is avoided.

The working head 240 is driven to rotate by the output shaft 220. Specifically, in the embodiment of the present invention, the output shaft 220 drives the working head 240 to work through the transmission mechanism. Referring to fig. 2 and 3, the hand-held power tool 100 further includes a transmission mechanism and a spacer 30, wherein the transmission mechanism is accommodated in the head housing 110, the spacer 30 is fixed in the head housing 110 and separates the first air inlet 213 from the transmission mechanism, the spacer 30 is provided with a vent 321 communicating the first air inlet 121 and the first air inlet 213, and the output shaft 220 passes through the spacer 30 and is connected to the transmission mechanism.

The partition 30 separates the space where the transmission mechanism is located from the space where the motor 20 is located, and it can be understood that the head shell 110 forms a reduction gearbox below the partition 30, and the partition 30 can be regarded as a part of the reduction gearbox. The partition frame 30 isolates the first cooling air path S1 from the space where the transmission mechanism is located, and the vent hole 321 on the partition frame 30 communicates with the first air inlet 121 and the first air inlet 213, so that the first path of the air that is divided after entering from the first air inlet 121 is blocked by the partition frame 30 and cannot flow downward, and only enters the first air inlet 213 through the vent hole 321, thereby establishing the first cooling air path S1.

In some embodiments, and referring to FIGS. 4 and 5, the shelf 30 includes a base plate 310 and a support ring 320 coupled to the base plate 310. The base plate 310 is fixed to the head housing 110 and isolates the first air inlet 213 from the transmission mechanism, the base plate 310 is provided with a first bearing hole 311 matched with the output shaft 220, the support ring 320 is arranged around the first bearing hole 311, the support ring 320 is provided with a vent hole 321, the head end 211 is embedded in the support ring 320, and the outer wall of the motor housing 210 is in sealing fit with the inner wall of the support ring 320.

With combined reference to fig. 4 and 5, in the attitude shown in fig. 2, the motor 20 is positioned above the base plate 310, and the head end 211 of the motor 20 is embedded in the support ring 320, while the outer wall of the motor casing 210 is in sealing contact with the inner wall of the support ring 320. The first path of the wind, which is divided after entering from the first airflow inlet 121, enters the space surrounded by the upper surface of the base plate 310, the support ring 320 and the head end 211 of the motor 20 from the vent hole 321, and then enters the interior of the motor 20 from the first wind inlet 213. The output shaft 220 passes through the first bearing hole 311 and is rotatably supported in the first bearing hole 311 by a bearing.

In this embodiment, the motor 20 is also fixed to the spacer 30. Specifically, referring to fig. 2 and 5, a connecting portion 330 having a through hole 331 is respectively disposed at two sides of the first bearing hole 311. After the motor housing 210 is inserted into the support ring 320, the motor housing 210 is supported by the two connection portions 330, and screws are inserted from below the base plate 310 through the through holes 331 of the connection portions 330 and connected to screw holes (not shown) of the motor housing 210, so that the motor 20 is fixed inside the head housing 110.

In the above arrangement, the partition 30 is assembled with the motor 20, and the partition 30 is utilized to guide the wind entering from the first airflow inlet 121 to flow to the first wind inlet 213 at the head end 211 of the motor casing 210, so that the structure is compact in the radial direction of the output shaft 220, and the design of miniaturization of the inner space of the head casing 110 is facilitated. The partition 30 simultaneously separates the transmission mechanism from the motor 20, and the transmission mechanism may form the first heat dissipation air path S1 even if the transmission mechanism is provided in the head housing 110, so the type of the hand-held power tool 100 is not limited to a lawn mower, and the partition 30 may be provided to form the first heat dissipation air path S1 in any hand-held power tool 100 in which the transmission mechanism (i.e., a speed reduction mechanism) needs to be connected to the output shaft 220, such as a chain saw, a pruner, a high pressure cleaner, and the like.

In the above embodiment, after the head end 211 of the motor casing 210 is inserted into the support ring 320, the head end 211 is spaced from the base plate 310, and the first air inlet 213 is located on a side of the vent hole 321 away from the base plate 310 in the axial direction of the output shaft 220. Referring to fig. 3, 4 and 5, the ventilating holes 321 are formed at the bottom of the support ring 320 near the bottom plate 310, and the first air inlets 213 are formed above the through holes 331. After entering the space surrounded by the support ring 320 from the ventilation holes 321, the wind flows upward and enters the inside of the motor 20 from the first wind inlets 213. The number of the vent holes 321 is not limited, and preferably, the vent holes 321 are opened at a plurality of positions along the circumferential direction of the support ring 320, for example, three vent holes 321 are uniformly distributed along the circumferential direction.

In some embodiments, the drive mechanism is supported by the base plate 310. The shelf 30 is fixed inside the head housing 110 and may also be used to support the transmission mechanism for compact structure. The shelf 30 is fixed inside the head shell 110, including at least the case that the shelf 30 is fixed with the head shell 110 by a fastener; secondly, the partition frame 30 and the head shell 110 are integrally formed.

In a specific embodiment, referring to fig. 2 and 3 together, the transmission mechanism includes a first gear 410, a second gear 420, and a transmission shaft 430, the first gear 410 is engaged with the second gear 420, the first gear 410 is fixed to the output shaft 220, the second gear 420 is fixed to the transmission shaft 430, and one end of the transmission shaft 430 is supported on the bottom plate 310. The transmission shaft 430 is located at one side of the output shaft 220, and the axis of the transmission shaft 430 is parallel to the axis of the output shaft 220. The upper end of the driving shaft 430 is supported to the base plate 310 by a first positioning bearing 431, and the lower end of the driving shaft 430 is used to connect the working head 240. The number of teeth of the first gear 410 is smaller than that of the second gear 420, thereby achieving the purpose of speed reduction.

As shown in fig. 2, a second bearing hole (not numbered) is formed on a side of the base plate 310 facing away from the motor 20, and an end of the transmission shaft 430 is supported in the second bearing hole through a first positioning bearing 431. When the bearing is specifically arranged, the second bearing hole is a sunken blind hole.

As also shown in fig. 2, in order to better support the transmission shaft 430, a second positioning bearing 432 supporting the transmission shaft 430 is further provided below the second gear 420 within the head housing 110. In this way, the first and second positioning bearings 431 and 432 support the transmission shaft 430 from both sides of the second gear 420, so that the transmission shaft 430 can stably and reliably rotate. In other embodiments, the second positioning bearing 432 may be eliminated, and the transmission shaft 430 is supported on the base plate 310 only by the first positioning bearing 431, thereby forming a cantilever shaft structure. At this time, the motor 20 and the transmission mechanism are supported by the partition frame 30, so that the arrangement of the components inside the head housing 110 is more compact, and no additional support structure is required to be arranged inside the head housing 110, thereby simplifying the internal structural design of the head housing 110.

As shown in fig. 2, the motor 20 includes a commutator (not shown) disposed on the output shaft 220, and a carbon brush 250 contacting the commutator, wherein the carbon brush 250 is located between the air outlet 215 and the second air inlet 214 in the axial direction of the output shaft 220. As shown in fig. 2, the air in the second cooling air path S2 enters the motor 20 from the second air inlet 214, and then blows over the carbon brush 250 to take away the heat generated by the carbon brush 250, and then flows out of the motor case 210 from the air outlet 215. In other words, the carbon brush 250 is positioned on the flow path of the wind passing through the second heat-dissipation wind path S2, so that the wind passing through the second heat-dissipation wind path S2 can cool the motor 20 well.

As shown in fig. 2, in order to better cool the motor 20, in some embodiments, a second airflow inlet 113 is further formed on the head casing 110 at a position close to the second air inlet 214, and when the fan 230 is driven by the output shaft 220 to rotate, a third cooling air path S3 is formed in the casing 10, which enters from the second airflow inlet 113, enters the motor 20 through the second air inlet 214, flows out of the motor 20 from the air outlet 215, and exits from the head casing 110 through the airflow outlet 111. The number and shape of the second airflow inlets 113 are not limited. Preferably, as shown in fig. 2, the second airflow inlet 113 is opened above the tail end 212 of the motor casing 210 and surrounds the motor casing 210 for a circle. Thus, when air is supplied from the second airflow inlet 113, the intake air volume is relatively large.

When the hand-held electric tool 100 is in operation, the air entering from the first air inlet 121 forms two cooling air flows flowing along the first cooling air path S1 and the second cooling air path S2, and the air entering from the second air inlet 113 forms one cooling air flow flowing along the third cooling air path S2, so that three cooling air flows are used for cooling the motor 20 from the inside and/or the outside of the motor 20, and the cooling effect on the motor 20 is good. The second air inlet 113 is close to the rear end 212 of the motor casing 210 and relatively far from the working head 240, so that the blockage probability is low, and even if the blockage occurs, the first cooling air path S1 and the second cooling air path S2 still have a cooling effect on the motor 20, thereby avoiding the burn-in.

In the above embodiment, each of the first air inlet 213 and the second air inlet 214 may further be provided with a protective net (not shown). Protective screens are arranged at the first air inlet 213 and the second air inlet 214, so that debris can be prevented from entering the interior of the motor casing 210 to a great extent. The mesh number (the larger the mesh number, the smaller the mesh aperture) of the protective net is generally 60-140, and if the mesh number is too small, the mesh is too large, so that scraps can easily pass through the mesh, and the effect of preventing the scraps cannot be achieved; if the mesh number is too large, the mesh is too small, which affects the air intake effect. Similarly, the first airflow inlet 121 and the second airflow inlet 113 may be respectively provided with a protection net.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims (10)

1. A hand-held power tool, comprising:

the shell comprises a head shell and a holding part arranged at an angle with the head shell, wherein the holding part is provided with a first airflow inlet, and the head shell is provided with an airflow outlet;

the motor is accommodated in the head shell and comprises a motor shell and an output shaft, the motor shell is provided with a head end and a tail end which are arranged oppositely, the output shaft extends out of the head end, the motor shell is provided with an air inlet and an air outlet, the air inlet comprises a first air inlet arranged at the head end and a second air inlet arranged at the tail end, and the air outlet is arranged between the head end and the tail end;

the fan is connected to the output shaft, and when the fan is driven by the output shaft to rotate, a first cooling air path which enters from the first air inlet, enters the motor through the first air inlet, flows out of the motor from the air outlet and is discharged out of the head shell from the air outlet is formed in the shell; and the second heat dissipation air path enters from the first air inlet, passes through between the motor shell and the head shell, enters the motor through the second air inlet, flows out of the motor from the air outlet and is discharged out of the head shell from the air outlet.

2. The hand-held power tool of claim 1, further comprising a transmission mechanism and a spacer, wherein the transmission mechanism is received in the head housing, the spacer is fixed in the head housing and separates the first air inlet from the transmission mechanism, the spacer is provided with a vent hole communicating the first air inlet and the first air inlet, and the output shaft passes through the spacer and is connected to the transmission mechanism.

3. The hand-held power tool of claim 2, wherein the spacer comprises a bottom plate and a support ring connected to the bottom plate, wherein the bottom plate isolates the first air inlet from the transmission mechanism, the bottom plate defines a first bearing hole engaged with the output shaft, the support ring is disposed around the first bearing hole, the support ring defines the vent hole, the head end is embedded in the support ring, and an outer wall of the motor housing is in sealing engagement with an inner wall of the support ring.

4. The hand held power tool as claimed in claim 3, wherein the head end is spaced from the base plate, and the first air inlet is located on a side of the air vent away from the base plate in an axial direction of the output shaft.

5. The hand held power tool according to claim 3, wherein the transmission mechanism is supported on the base plate.

6. The hand-held power tool according to claim 5, wherein the transmission mechanism includes a first gear, a second gear, and a transmission shaft, the first gear is engaged with the second gear, the first gear is fixed to the output shaft, the second gear is fixed to the transmission shaft, one end of the transmission shaft is supported by the base plate, and an axis of the transmission shaft is parallel to an axis of the output shaft.

7. The hand held power tool according to claim 6, wherein a second bearing hole is formed in the base plate, and one end of the transmission shaft is supported in the second bearing hole by a bearing.

8. The hand held power tool of claim 1, wherein the motor includes a carbon brush, wherein the carbon brush is located at a position between the air outlet and the second air inlet in an axial direction of the output shaft.

9. The hand-held power tool according to claim 1, wherein a second airflow inlet is formed in the head housing at a position close to the second air inlet, and when the fan is rotated by the output shaft, a third cooling airflow path is formed in the housing, which enters from the second airflow inlet, enters the motor through the second air inlet, flows out of the motor through the air outlet, and is discharged out of the head housing through the airflow outlet.

10. The hand held power tool according to claim 1, wherein the fan is disposed inside the motor housing at a position near the air outlet.

Images