Handheld electric tool and motor assembly for electric tool

1 . A handheld electric tool, the handheld electric tool comprising:

a housing defining an installation opening, a gas inlet, and a gas outlet, the housing comprising a separating rib extending from an inner wall of the housing between the gas inlet and the gas outlet;

a working member, installed at the installation opening of the housing and protruding outward from the housing;

a motor disposed in the housing, the motor having a far-side end close to the working member and a near-side end remote from the working member; and

a motor support, disposed in the housing comprising:

a first part, positioned at the far-side end of the motor and fixedly connected to the housing, and

a second part, extending from the first part into an interior of the motor and fixedly connected to a stator of the motor;

wherein the second part is provided with a first through-hole for a rotor shaft of the motor to pass through, and an output end of the rotor shaft extends through the first through-hole and drives the working member to move;

wherein the first part defines one or more second through-holes in fluid communication with the gas inlet and the gas outlet for airflow to pass through;

wherein the gas inlet is close to the far-side end and the gas outlet is close to the near-side end; and

wherein the motor is configured such that during operation thereof, airflow can be sucked in through the gas inlet, flow through the one or more second through-holes in the motor support and the motor and finally be discharged through the gas outlet, driven by a rotary action of fan blades arranged around the rotor shaft.

2 . The handheld electric tool according to claim 1 , wherein the first part of the motor support is formed as a plate-like structure,

and an engagement slot is provided in an inner wall of the housing, the plate-like structure being correspondingly held in the engagement slot.

3 . The handheld electric tool according to claim 1 , wherein the motor is an external-rotor motor, and the second part is formed as a tubular structure engaged with a circumferential inner wall of the stator, the tubular structure defining the first through-hole.

4 . The handheld electric tool according to claim 1 , wherein one end of a rotor of the motor is provided with a rotation conduction component arranged around the rotor shaft, the rotation conduction component being connected to both the rotor shaft and a body of the rotor in such a way as to be incapable of relative rotation.

5 . The handheld electric tool according to claim 1 , wherein a bearing is installed in the first through-hole, the bearing supporting the rotor shaft rotatably.

6 . The handheld electric tool according to claim 5 , wherein a nearest-end part and a farthest-end part in the first through-hole are each provided with one said bearing.

7 . The handheld electric tool according to claim 1 , wherein the rotor shaft has a near-side extremity extending out of a body of the motor, at least one bearing being installed at the near-side extremity.

8 . The handheld electric tool according to claim 1 , wherein the separating rib defines a recess having a U-shape, the recess of the U-shape facing towards the near-side end of the motor, and the motor support being accommodated in the recess in a size-fitted manner.

9 . The handheld electric tool according to claim 1 , wherein the gas inlet is positioned at the side of the first part of the motor support that faces away from the motor, and wherein the second through-holes extend parallel to the rotor shaft.

10 . The handheld electric tool according to claim 1 , wherein the handheld electric tool further comprises a PCB which is disposed in the housing and close to the motor, the gas inlet being positioned so as to be simultaneously close to the PCB, so that sucked-in gas flows through the PCB and then through the motor.

11 . The handheld electric tool according to claim 1 , wherein the housing comprises a motor region for accommodating the motor and a gripping region for a user to grasp, the motor region being an axially symmetric structural body, wherein an axial direction of the rotor shaft of the motor deviates from an axis of symmetry of the motor region.

12 . The handheld electric tool according to claim 11 , wherein an angle (α) between the axial direction of the rotor shaft of the motor and the axis of symmetry of the motor region is 10°-60°.

13 . The handheld electric tool according to claim 11 , wherein the motor region of the housing has a characteristic housing part parallel to the axis of symmetry, a distance between the characteristic housing part and the near-side end of the motor being less than the distance between the characteristic housing part and the far-side end of the motor, and

the handheld electric tool comprises a PCB, the PCB being positioned so as to be partially located between a supporting member of the motor and the characteristic housing part.

14 . The handheld electric tool according to claim 11 , wherein the housing further comprises a central region, wherein the motor region, the gripping region and the working member are arranged so as to extend outwards around the central region, and a transmission mechanism for transmitting an output of the motor to the working member is provided in the central region.

15 . The handheld electric tool according to claim 1 , wherein the handheld electric tool is a handheld trimming device; and the working member is a cutting member.

16 . The handheld electric tool according to claim 15 , wherein the handheld electric tool further comprises a guard which projects from the housing and partially covers the working member, and the housing has a pair of clamping structures located at the opening, the guard being pivotably clamped between the pair of clamping structures.

17 . The handheld electric tool according to claim 16 , wherein the handheld electric tool is configured to enable the guard to freely pivot away from the working member relative to the pair of clamping structures, so as to allow the guard to be pushed up by an operation target object during operation of the handheld electric tool.

18 . The handheld electric tool according to claim 1 , wherein the first part comprises a circular plate and two wing plates extending from the circular plate, wherein the two wing plates are arranged symmetrically about the circular plate, and wherein the circular plate defines the one or more second through-holes.

19 . A motor assembly for a handheld electric tool, the motor assembly comprising:

a motor comprising a far-side end close to a motive power output end of the motor and a near-side end remote from the motive power output end; and

a motor support, comprising:

a first part, positioned at the far-side end of the motor and comprising at least one fixed characteristic, and

a second part, extending from the first part into an interior of the motor and fixedly connected to a stator of the motor;

wherein the second part is provided with a first through-hole for a rotor shaft of the motor to pass through, the rotor shaft passing through the first through-hole, and a far-side extremity and a near-side extremity of the rotor shaft both extending out of a body of the motor assembly;

wherein the first part defines one or more second through-holes extending parallel to the rotor shaft for airflow to pass through; and

wherein the first part comprises a circular plate and two wing plates extending from the circular plate, the circular plate defining the one or more second through-holes.

20 . The motor assembly according to claim 19 , wherein the first part of the motor support is formed as a plate-like structure.

21 . The motor assembly according to claim 19 , wherein the motor is an external-rotor motor, and the second part is formed as a tubular structure engaged with a circumferential inner wall of the stator, the tubular structure defining the first through-hole.

22 . The motor assembly according to claim 19 , wherein one end of a rotor of the motor is provided with a rotation conduction component arranged around the rotor shaft, the rotation conduction component being connected to both the rotor shaft and a body of the rotor in such a way as to be incapable of relative rotation.

23 . The motor assembly according to claim 19 , wherein a bearing is installed in the first through-hole, the bearing supporting the rotor shaft rotatably.

24 . The motor assembly according to claim 23 , wherein a nearest-end part and a farthest-end part in the first through-hole are each provided with one said bearing.

25 . The motor assembly according to claim 19 , wherein at least one bearing is installed on the near-side extremity of the rotor shaft that projects from a body of the motor.