Electric grinding machine tool

Abstract

An electric grinding machine tool comprises a machine shell, an electric motor arranged in the machine shell, a motor end plate arranged in the machine shell and used for arranging the electric motor, and an airflow generating piece connected with the electric motor. At least one air inlet hole is formed in the machine shell. The motor end plate is provided with at least one passing opening which is not shielded by the electric motor and at least one first annular structure which is arranged on one side far away from the electric motor. The airflow generating piece rotates along with the electric motor, so that a heat dissipation airflow which enters from the at least one air inlet hole, flows through the surface of the electric motor and then passes through the passing opening is generated in the machine shell, and at least one second annular structure matched with the at least one first annular structure is formed by the airflow generating piece. The at least one first annular structure and the at least one second annular structure jointly define a plurality of dust blocking points.

Description

Technical Field

[0001] The utility model provides an electric grinding machine tool, in particular to an electric grinding machine tool with a dustproof design. Background Art

[0002] The most criticized problem of electric grinding machine tools is that the waste heat generated by the electric motor or control circuit board during long-term grinding operations can easily cause the user's palms to feel high temperatures, making it difficult to continue using them.

[0003] Although many companies have proposed solutions to this problem, such as CN106392836B and TWI796281, the electric motor needs to be equipped with a motor end plate to limit the entry of dust, which limits the position of the airflow generating element. Utility Model Content

[0004] The main purpose of the utility model is to solve the problems existing in the conventional structure.

[0005] In order to achieve the above-mentioned purpose, the utility model provides an electric grinding tool machine, comprising a housing, an electric motor, a motor end plate, and an airflow generating member. The housing forms at least one air inlet. The motor end plate forms at least one passage and at least one first annular structure, the at least one passage is not shielded by the electric motor, and the at least one first annular structure is arranged on a side away from the electric motor. The airflow generating member rotates with the electric motor, and the airflow generating member generates a heat dissipation airflow in the housing. The heat dissipation airflow enters from the at least one air inlet, flows through the surface of the electric motor, and then passes through the at least one passage to flow toward the position where the airflow generating member is located. The airflow generating member forms at least one second annular structure, and the at least one second annular structure cooperates with the at least one first annular structure. The at least one first annular structure and the at least one second annular structure jointly define a plurality of dust blocking points.

[0006] In one embodiment, the number of the at least one first ring structure and the number of the at least one second ring structure are N and N+1 respectively, and N is greater than or equal to 1.

[0007] In one embodiment, the airflow generating member has a substrate and a plurality of blades. The plurality of blades are disposed on the substrate, the plurality of blades and the at least one second annular structure are disposed on the same surface of the substrate, and the plurality of blades are closer to the edge of the substrate than the at least one second annular structure.

[0008] In one embodiment, the at least one opening is disposed near the outer edge of the electric motor, and the at least one first annular structure is disposed within the projection range of the electric motor.

[0009] In one embodiment, the electric motor has a rotor and a stator. The stator surrounds the rotor and at least a portion of the stator is exposed on the surface of the electric motor.

[0010] In one embodiment, the electric grinding tool has a control circuit board, which is disposed in the housing and connected to the electric motor, and the at least one air inlet is disposed close to the control circuit board.

[0011] In one embodiment, the housing has an exhaust hole, and the exhaust hole faces the airflow generating member.

[0012] In one embodiment, the airflow generating member is disposed between an eccentric block and the motor end plate.

[0013] In one embodiment, the at least one first annular structure does not contact the airflow generating member, and the at least one second annular structure does not contact the motor end plate.

[0014] Through the above implementation of the utility model, compared with the conventional method, the utility model has the following characteristics: the heat dissipation airflow of the utility model passes through the surface of the electric motor, which can effectively reduce the temperature of the electric motor and increase the comfort of the user's grip. The fine dust entrained by the heat dissipation airflow cannot enter from the surface of the electric motor, and cannot enter the electric motor from between the airflow generating part and the motor end plate. The utility model can achieve the purpose of dust prevention without affecting the movement of the airflow generating part and adding other components through the design of the at least one first annular structure and the at least one second annular structure. Furthermore, the utility model makes the structure of the electric grinding tool more compact and effectively reduces the volume through the above structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 , is a structural cross-sectional view of an embodiment of the electric grinding tool of the utility model;

[0016] Figure 2 , is a partial exploded view of an embodiment of the electric grinding tool of the utility model;

[0017] Figure 3 , is a schematic structural diagram of a motor end plate and an airflow generating member of an embodiment of an electric grinding tool machine of the utility model;

[0018] Figure 4 , is a cross-sectional structural diagram of a local structure of an embodiment of the electric grinding tool of the utility model;

[0019] Figure 5 , is a schematic diagram of the airflow path of an embodiment of the electric grinding tool machine of the utility model (I);

[0020] Figure 6 , is a schematic diagram of the airflow path of an embodiment of the electric grinding tool machine of the utility model (II).

[0021]

Explanation of symbols

[0022] 20: Electric grinding machine tools

[0023] 21: Casing

[0024] 211: Air intake

[0025] 212: Exhaust hole

[0026] 22: Electric Motor

[0027] 221: Shaft

[0028] 222: Rotor

[0029] 223: Stator

[0030] 224: Eccentric block

[0031] 23: Motor end plate

[0032] 231: Pass

[0033] 232: First ring structure

[0034] 24: Airflow generating parts

[0035] 241: Second ring structure

[0036] 242: Substrate

[0037] 243: Fan Blade

[0038] 25: Palin

[0039] 26: Tool holder

[0040] 27: Grinding disc

[0041] 28: Control circuit board

[0042] 29: Dust cover

[0043] 30: Gap

[0044] 31: Cooling airflow

[0045] 311: Dust blocking point

[0046] 32: Gap DETAILED DESCRIPTION

[0047] The detailed description and technical content of the utility model are now described as follows with reference to the accompanying drawings:

[0048] See also Figures 1 to 3The utility model provides an electric grinding tool machine 20, which is a hand tool machine. The electric grinding tool machine 20 includes a housing 21, an electric motor 22, a motor end plate 23, and an airflow generating member 24. The housing 21 is hollow, and the housing 21 forms at least one air inlet 211. The electric motor 22 is disposed in the housing 21. Specifically, the electric motor 22 is fixed on the motor end plate 23. When the motor end plate 23 and the housing 21 are assembled, the electric motor 22 is placed in the housing 21 together. In addition to fixing the position of the electric motor 22 in the housing 21, the motor end plate 23 further seals a portion of the electric motor 22 to limit external substances from entering the electric motor 22. The motor end plate 23 is formed with at least one opening 231 and at least one first annular structure 232. The at least one opening 231 is not shielded by the electric motor 22, and the at least one opening 231 passes through the motor end plate 23. The at least one opening 231 may be a through hole, or formed by a hollow portion on the motor end plate 23. The at least one first annular structure 232 is disposed on a side of the motor end plate 23 away from the electric motor 22. In one embodiment, the position of the at least one first annular structure 232 is relative to the motor end plate 23 to close the portion of the electric motor 22.

[0049] See also Figure 4 , the airflow generating member 24 is connected to the electric motor 22. The airflow generating member 24 forms at least one second annular structure 241, and the at least one second annular structure 241 cooperates with the at least one first annular structure 232. The at least one second annular structure 241 and the at least one first annular structure 232 can be annular walls or annular grooves respectively. When the electric grinding tool 20 is assembled, a gap 30 is formed between the at least one second annular structure 241 and the at least one first annular structure 232. The at least one second annular structure 241 and the at least one first annular structure 232 further define a plurality of dust blocking points 311 in the gap 30 together. The plurality of dust blocking points 311 are all located at the bend of the gap 30, and the dust blocking effect is achieved through a non-straight path.

[0050] See also Figure 5 and Figure 6, the airflow generating member 24 rotates with the electric motor 22, and when the airflow generating member 24 rotates, a heat dissipation airflow 31 is generated in the housing 21. The heat dissipation airflow 31 enters from the at least one air inlet 211, flows through the surface of the electric motor 22, and then flows to the airflow generating member 24 through the at least one through hole 231, and finally is discharged at a place of the housing 21. It should be understood that the gap 30 formed by the at least one first annular structure 232 and the at least one second annular structure 241 of the utility model is not located on the main path of the heat dissipation airflow 31. The heat dissipation airflow 31 of the utility model passes through the surface of the electric motor 22, and can effectively reduce the temperature of the electric motor 22 and increase the comfort of the user's grip. The fine dust entrained by the heat dissipation airflow 31 cannot enter from the surface of the electric motor 22, and cannot enter the electric motor 22 from between the airflow generating member 24 and the motor end plate 23. The utility model can achieve the purpose of dust prevention through the above design without affecting the movement of the airflow generating member 24 and adding other components. Furthermore, the utility model makes the structure of the electric grinding tool 20 more compact and effectively reduces the volume through the above structure.

[0051] Please refer to Figure 4 In one embodiment, the number of the at least one first annular structure 232 and the at least one second annular structure 241 are N and N+1 respectively, wherein N is greater than or equal to 1. Taking the drawings of the present invention as an example, the number of the second annular structure 241 is one, the number of the first annular structure 232 is two, the second annular structure 241 and the two first annular structures 232 are arranged at intervals, and the second annular structure 241 is located between the two first annular structures 232. The plurality of dust blocking points 311 are distributed at the turning point of the gap 30 formed by the two first annular structures 232 and the second annular structure 241. Furthermore, one of the two first annular structures 232 can be used to fix a bearing 25.

[0052] Please refer to Figure 4 In one embodiment, the at least one first annular structure 232 may not contact the airflow generating member 24, and the at least one second annular structure 241 may not contact the motor end plate 23 through structural design. Further, the airflow generating member 24 may be disposed between an eccentric block 224 and the motor end plate 23. Further, the airflow generating member 24 is supported on the eccentric block 224, thereby ensuring that the at least one first annular structure 232 does not contact the airflow generating member 24, and the at least one second annular structure 241 does not contact the motor end plate 23. As mentioned above, the eccentric block 224 is connected to a rotating shaft 221, and a tool holder 26 is provided therein, and the tool holder 26 is provided with a grinding disc 27. The tool holder 26 generates self-rotation when the electric motor 22 rotates, thereby driving the grinding disc 27 to rotate.

[0053] Please refer to Figure 3 and Figure 4 In one embodiment, the airflow generating member 24 has a base plate 242 and a plurality of blades 243. The plurality of blades 243 are disposed on the base plate 242, the plurality of blades 243 and the at least one second annular structure 241 are disposed on the same surface of the base plate 242, and the plurality of blades 243 are closer to the edge of the base plate 242 than the at least one second annular structure 241.

[0054] Please refer to Figure 4 In one embodiment, the at least one opening 231 is disposed near the edge of the electric motor 22 to reduce the turbulence generated by the heat dissipation airflow 31 there. If the motor end plate 23 is formed with a plurality of the openings 231, the plurality of the openings 231 will be disposed along the edge of the electric motor 22, and the plurality of the openings 231 can be disposed at equal intervals. On the other hand, the at least one first annular structure 232 is disposed within the projection range of the electric motor 22. Specifically, the at least one first annular structure 232 is located on the portion of the motor end plate 23 that encloses the electric motor 22.

[0055] Please refer to Figure 3 and Figure 4 The electric motor 22 has a rotor 222 and a stator 223, and the stator 223 is disposed around the rotor 222. In one embodiment, a portion of the stator 223 is exposed on the surface of the electric motor 22, that is, the heat dissipation airflow 31 can directly dissipate heat from the stator 223.

[0056] Please refer to Figure 1 and Figure 6 The electric grinding tool 20 has a control circuit board 28, which is disposed in the housing 21 and connected to the electric motor 22. In one embodiment, the at least one air inlet 211 is disposed close to the control circuit board 28 so that the heat dissipation airflow 31 passes through the control circuit board 28 to dissipate heat from the electronic components on the control circuit board 28.

[0057] Please refer to Figure 4 and Figure 6 In one embodiment, the housing 21 has an exhaust hole 212, the exhaust hole 212 faces the airflow generating member 24, and the exhaust hole 212 serves as the end point of the heat dissipation airflow 31 flowing in the housing 21. In addition to the above, the exhaust of the heat dissipation airflow 31 of the utility model can also be implemented in other ways, such as exhausting through a gap 32 between the grinding disc 27 and a dust cover 29.

Claims

1. An electric grinding machine tool, characterized in that: Include: A housing, forming at least one air inlet; an electric motor disposed in the housing; a motor end plate, disposed in the housing and provided with the electric motor disposed thereon, the motor end plate forming at least one opening not shielded by the electric motor, and at least one first annular structure disposed on a side away from the electric motor; and An airflow generating member is connected to the electric motor and generates a heat dissipation airflow in the housing as the electric motor rotates. The heat dissipation airflow enters from the air inlet, flows through the surface of the electric motor, and then passes through the at least one opening. The airflow generating member forms at least one second annular structure that cooperates with the at least one first annular structure. The at least one first annular structure and the at least one second annular structure jointly define a plurality of dust blocking points.

2. The electric grinding tool according to claim 1, characterized in that: The number of the at least one first ring structure and the number of the at least one second ring structure are N and N+1 respectively, and N is greater than or equal to 1.

3. The electric grinding tool according to claim 1 or 2, characterized in that: The airflow generating component has a base plate and a plurality of blades arranged on the base plate. The plurality of blades and the at least one second annular structure are arranged on the same surface of the base plate. The plurality of blades are closer to the edge of the base plate than the at least one second annular structure.

4. The electric grinding tool according to claim 3, characterized in that: The at least one opening is arranged close to the surface edge of the electric motor, and the at least one first annular structure is arranged within the projection range of the electric motor.

5. The electric grinding tool according to claim 4, characterized in that: The electric motor has a rotor and a stator surrounding the rotor, and at least a part of the stator is exposed on the surface of the electric motor.

6. The electric grinding tool according to claim 5, characterized in that: The electric grinding tool machine has a control circuit board which is arranged in the housing and connected to the electric motor, and the air inlet is close to the control circuit board.

7. The electric grinding tool according to claim 6, characterized in that: The housing has an exhaust hole facing the airflow generating component.

8. The electric grinding tool according to claim 7, characterized in that: The airflow generating member is arranged between an eccentric block and the motor end plate.

9. The electric grinding tool according to claim 8, characterized in that: The at least one first annular structure does not contact the airflow generating member, and the at least one second annular structure does not contact the motor end plate.

10. The electric grinding tool according to claim 1 or 2, characterized in that: The housing has an exhaust hole facing the airflow generating component.

11. The electric grinding tool according to claim 1 or 2, characterized in that: The motor end plate forms a plurality of the through openings, and the plurality of the through openings are arranged along the edge of the electric motor.

12. The electric grinding tool according to claim 1 or 2, characterized in that: The airflow generating member is arranged between an eccentric block and the motor end plate.

13. The electric grinding tool according to claim 12, characterized in that: The at least one first annular structure does not contact the airflow generating member, and the at least one second annular structure does not contact the motor end plate.

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