CN220516724U - Electric tool - Google Patents

Abstract

The utility model provides an electric tool, including the casing, accept in the motor element and the controller of driving motor element of casing, the controller includes the controller casing, the motor element includes the bearing of supporting in the tip of motor element, the casing has the holder of installation bearing, the holder has the opening of running through the wall and the first terminal surface that deviates from the bearing, the controller casing has the second terminal surface that faces first terminal surface, at least one of first terminal surface and second terminal surface has the bellying, bellying butt in the other one of first terminal surface and second terminal surface.

Description

Electric tool

[ technical field ]

The utility model relates to the technical field of electric tools, in particular to an electric tool with an improved dustproof structure.

[ background Art ]

The brushless electric tool is a tool which drives a motor to rotate through a controller so as to work a workpiece, and has the advantages of high processing efficiency and long service life. The controller of existing brushless power tools, particularly angle grinders, is typically mounted at the rear end of the housing in close proximity to the bearing housing where the rotor shaft is mounted. To meet the assembly requirement, the bearing chamber is generally disposed close to the end face of the controller in a through hole or concentric circle structure, but such a structure may bring dust in the cooling air flow into the motor during operation of the electric tool, which affects the service life of the motor. At present, to the dustproof problem of bearing room, can increase rubber O type circle in order to carry out the filling in gap between bearing room's outer terminal surface and controller casing generally, but in assembly and maintenance process, O type circle neglected loading easily, drop, leads to dustproof function to become invalid.

For dust prevention improvement of the electric tool, refer to the chinese patent No. 201580034929.9 published on 10 and 9 in 2019, which discloses a dust prevention structure of a bearing frame and a controller: the opening portion at the rear of the bearing bracket is not exposed to the cooling wind by a cup-shaped cover portion formed at the front end of the controller housing. This structure can reduce the dust that flows to the inside of the motor, but the cup-shaped cover part is unavoidable to have a gap with the bearing frame because the cup-shaped cover part cannot be arranged to remain fixed with the bearing frame in terms of assembly requirements, resulting in that part of the dust flows to the motor through the gap, and thus damages the motor.

In view of the above, it has been determined that it is necessary to provide an improved power tool that overcomes the deficiencies of the prior art.

[ summary of the utility model ]

In view of the shortcomings of the prior art, the utility model aims to provide an electric tool with a dustproof device, which has the advantages of simple and convenient manufacture and high dustproof efficiency.

The utility model solves the problems in the prior art by adopting the following technical scheme: the utility model provides an electric tool, includes the casing, accept in motor assembly and the drive of motor assembly's controller, the controller includes the controller casing, motor assembly including support in motor assembly's tip bearing, the casing has the installation the holder of bearing, the holder has the opening that runs through the wall, the holder includes the first terminal surface that deviates from the bearing, the controller casing has the second terminal surface that faces towards the first terminal surface, at least one of first terminal surface and the second terminal surface has the bellying, the bellying butt in another one of first terminal surface and the second terminal surface.

The further improvement scheme is as follows: the motor assembly comprises a rotor shaft, the rotor shaft is provided with a rotation axis, the protruding portion is a circular ring, the rotation axis extends through the circle center of the circular ring, and the opening is formed in the inner side of the circular ring.

The cross section of the protruding portion is formed into a cone portion, the angle of the cone portion is 5-120 degrees, and the height of the cone portion is 0.3-3 mm.

The further improvement is that the taper part is embedded into the first end face and/or the second end face.

The further improvement is that the cone is pressed and seals the gap between the first end face and the second end face.

The second end face is provided with an arc-shaped edge, and the circular ring is arranged on the inner side of the arc-shaped edge.

The retainer is provided with a first positioning hole extending from the first end face, the controller shell comprises a second positioning hole extending from the second end face, and the first positioning hole and the second positioning hole are equal in diameter.

The further improvement scheme is that the first positioning holes and the second positioning holes are penetrated with bolts or pins.

The further improvement scheme is that the protruding portion and the controller shell are made of one of ABS, PC and PA.

The further improved scheme is that a positioning disk is arranged on the inner wall of the shell, and the positioning disk and the retainer are integrally formed.

Compared with the prior art, the utility model has the following beneficial effects:

1. the end face of the shell retainer and/or the end face of the controller shell are provided with the integrally formed protruding parts, and the protruding parts are used for sealing gaps between the shell retainer and the controller shell, so that the problems that O-shaped rings are missed and easy to break when rubber O-shaped rings are used for sealing in the prior art are effectively solved.

2. The bulge is arranged to encircle the open-ended ring, the cross section of the bulge is arranged to be a cone, and when the cone is mutually abutted with the controller shell, one of the cone is deformed, and the cone and the other of the cone are matched to form a sealing structure so as to fill a gap between the cone and the controller shell, so that dust can be prevented from entering the motor through the opening, and the motor has a simple structure and high dustproof efficiency.

[ description of the drawings ]

The following describes the embodiments of the present utility model in further detail with reference to the accompanying drawings:

FIG. 1 is a schematic perspective view of a power tool according to a preferred embodiment of the present utility model;

FIG. 2 is a cross-sectional view of the power tool of FIG. 1;

FIG. 3 is a schematic view of the structure of the holder of the power tool of FIG. 2;

FIG. 4 is a schematic view of the cage of FIG. 3 from another perspective;

FIG. 5 is a schematic diagram of a controller in the power tool of FIG. 2;

FIG. 6 is a schematic view of the power tool of FIG. 2 with a boss abutting a controller housing;

FIG. 7 is a schematic view of another embodiment of the power tool of FIG. 2 in which the protrusion abuts the controller housing;

fig. 8 is a schematic cross-sectional view of the boss shown in fig. 3.

Meaning of reference numerals in the drawings:

electric tool 100 case 1

First end face 111 of cage 11

Boss 112 opening 113

Cone 115 of ring 114

Positioning hole 116 positioning disk 12

Stator 21 of motor assembly 2

Rotor 22 rotor shaft 23

Bearing 24 mounting bracket 25

Rotation axis 26 controller 3

Second end face 32 of controller housing 31

Arcuate edge 321 second locating hole 33

Gap 34 drive assembly 4

Bevel gear 41 bevel gear 42

Output shaft 43

Detailed description of the preferred embodiments

The terminology used in the present utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. Words such as "upper", "lower", "front", "rear", etc., indicating an azimuth or a positional relationship are based on only the azimuth or the positional relationship shown in the drawings, and are merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus/elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the present utility model.

Referring to fig. 1 to 2, an embodiment of the present utility model relates to a power tool 100, and the power tool 100 may be an angle grinder, an electric hammer, an electric pick, etc., and is preferably exemplified herein as an angle grinder. The angle grinder 100 comprises a housing 1, a motor assembly 2 accommodated in the housing 1, a controller 3 driving the motor assembly 2, and a transmission assembly 4 connected to the motor assembly 2; the shell 1 is provided with a positioning disk 12 extending from the inner wall, the positioning disk 12 is annular, a retainer 11 is connected with the positioning disk 12 through a plurality of ribs, and the retainer 11 and the positioning disk 12 are integrally formed; the motor assembly 2 comprises a stator 21 clamped on the shell 1, a rotor 22 penetrating through the stator 21 and a rotor shaft 23, wherein the end part of the rotor shaft 23 is arranged on a mounting frame 25 through a bearing 24, and the mounting frame 25 is made of metal and is embedded in the retainer 11; the controller 3 includes a controller housing 31 disposed opposite to the holder 11, and the controller 3 is mounted to the inner wall of the casing 1 through the controller housing 31; the transmission assembly 4 includes a bevel gear 41 mounted on the front end of the rotor shaft 23, a bevel gear 42 engaged with the bevel gear 41, and an output shaft 43 integrally rotated with the bevel gear 42; energizing the angle grinder 100, the controller 3 drives the rotor shaft 23 to move about the rotational axis 26 and rotates the output shaft 43 via the bevel gear 41, thereby operating the tip tool on the workpiece, during which external cooling air is drawn into the angle grinder 100 to cool the motor assembly 4.

Referring to fig. 3 to 5, the retainer 11 includes a first end surface 111 facing away from the mounting frame 25 and a protruding portion 112 extending from the first end surface 111, a circular opening 113 is penetrated through a central portion of the first end surface 111, the protruding portion 112 is a circular ring 114, the opening 113 is concentric with the circular ring 114 and is located at an inner side of the circular ring 114, and the rotation axis 26 passes through the center of the circular ring 114 and the opening 113; the controller shell 31 is provided with a second end face 32, the second end face 32 is outwards extended with a second positioning hole 33 and is limited with an arc-shaped edge 321, correspondingly, the first end face 111 is outwards extended with a first positioning hole 116, and the second positioning hole 33 is equal in diameter with the first positioning hole 116; when the controller 3 is installed, the second end face 32 can be placed towards the first end face 111, then an external force is applied to the controller 3 to push the controller forward along the casing 1 until the second end face 32 abuts against the protruding portion 112, and then the first positioning hole 116 and the second positioning hole 33 are fixed by bolts or pins; after installation, the ring 114 is positioned inside the arcuate edge 321, i.e., the boss 112 is completely covered by the second end face 32, which effectively reduces dust in the cooling air from entering the motor assembly 2 through the opening.

When the controller housing 31 is fixed to the holder 11, the boss 112 abuts against the second end face 32, and one of the two is deformed, and in the deformed state, the two cooperate to form a seal structure that can fill the gap between the holder 11 and the controller 3; in order to ensure that the boss 112 and the controller housing 31 can deform, brittle materials, preferably one of ABS, PC and PA, are selected; in the following description of the sealing structure formed by the protruding portion 112 and the second end face 32, referring to fig. 6, when the protruding portion 112 abuts against the second end face 32, the protruding portion 112 pierces the wall of the second end face 32, and at this time, the protruding portion 112 is not deformed, the second end face 32 forms a recess, and the gap 34 is filled by the protruding portion 112; referring to fig. 7, the protrusion 112 abuts against the second end face 32, the second end face 32 is not deformed, the protrusion 112 is pressed, and the gap 34 is filled; both of the above-mentioned sealing structures are formed by blocking the gap between the holder 11 and the controller housing 31 to isolate dust from the outside, and prevent dust from entering the motor assembly 4 through the opening 113.

It should be noted that, although the protruding portion 112 is circular, the cross section of the protruding portion 112 is not circular, and referring to fig. 8, the cross section of the protruding portion 112 is a cone portion 115, the cone portion 115 has specific parameter requirements, and the angle of the cone portion 115 is defined as a, the height is B, a is preferably 5 ° to 120 °, particularly preferably 5 ° to 90 °, particularly preferably 5 ° to 60 °, B is preferably 0.3mm to 3mm, particularly preferably 0.5mm to 2mm, and particularly preferably 0.6 to 1.2mm.

In another embodiment of the present utility model, the protruding portion 112 may be disposed on the second end surface 32, and the opening 113 on the first end surface 111 is correspondingly disposed inside the circular ring 114 formed by the protruding portion 112; in yet another embodiment of the present utility model, the first end surface 111 and the second end surface 32 are provided with protruding portions 112, wherein an inner circumference of one protruding portion abuts against an outer circumference of the other protruding portion, forming a labyrinth dust-proof structure.

The present utility model is not limited to the above-described embodiments. Those skilled in the art will readily appreciate that many alternatives are available for the power tool of the present utility model without departing from the spirit and scope of the present utility model. The protection scope of the present utility model is subject to the claims.

Claims (10)

1. An electric tool, includes the casing, accept in motor assembly and the drive of casing motor assembly's controller, the controller includes the controller casing, motor assembly including support in motor assembly's tip bearing, the casing has the installation the holder of bearing, the holder has the opening that runs through the wall, its characterized in that: the cage includes a first end face facing away from the bearing, the controller housing has a second end face facing the first end face, at least one of the first end face and the second end face has a boss that abuts the other of the first end face and the second end face.

2. The power tool of claim 1, wherein: the motor assembly comprises a rotor shaft, the rotor shaft is provided with a rotation axis, the protruding portion is a circular ring, the rotation axis extends through the circle center of the circular ring, and the opening is formed in the inner side of the circular ring.

3. The power tool of claim 2, wherein: the cross section of the protruding portion is formed into a cone portion, the angle of the cone portion is 5 degrees to 120 degrees, and the height of the cone portion is 0.3mm to 3mm.

4. A power tool according to claim 3, wherein: the taper is embedded in the first end face and/or the second end face.

5. A power tool according to claim 3, wherein: the taper is compressed and seals a gap between the first end face and the second end face.

6. The power tool of claim 2, wherein: the second end face is provided with an arc-shaped edge, and the circular ring is arranged on the inner side of the arc-shaped edge.

7. The power tool of claim 6, wherein: the retainer has a first locating hole extending from the first end face, the controller housing includes a second locating hole extending from the second end face, and the first locating hole is equal in diameter to the second locating hole.

8. The power tool of claim 7, wherein: the first positioning hole and the second positioning hole are penetrated with bolts or pins.

9. The power tool of claim 1, wherein: the material of the protruding part and the controller shell is one of ABS, PC and PA.

10. The power tool of claim 1, wherein: the inner wall of the shell is provided with a positioning disc, and the positioning disc and the retainer are integrally formed.