CN118046308A - Electric grinding machine tool and housing thereof - Google Patents

Abstract

An electric grinding machine tool and a housing thereof are provided, wherein the electric grinding machine tool comprises an electric motor, an airflow generating member and a housing. The shell comprises a hollow shell, a motor shade arranged in the hollow shell, two partition plates arranged between the side wall of the motor shade and the hollow shell, at least one air outlet facing the air flow generating piece, a first air inlet formed on the hollow shell, and at least one second air inlet formed on the hollow shell and spaced from the first air inlet. When the airflow generating member is started, the first air inlet generates a pressure difference in the hollow shell at a part close to the motor shade, so as to cause the air inlet of the second air inlet.

Description

Electric grinding machine tool and housing thereof

Technical Field

The present invention relates to an electric grinding machine tool, and more particularly, to an electric grinding machine tool having a housing with a large air intake design.

Background

In the conventional electric grinding machine tool, an air flow generating member is attached to an eccentric block, and air flow for radiating the inside is generated by the air flow generating member, so that waste heat generated when an electric motor or a circuit board works is discharged. One embodiment is disclosed in EP2132000B1, or can be seen with reference to fig. 1. In the solution disclosed in fig. 1, a polishing disc cover 61 of the electric polishing tool machine 60 is laterally provided with a plurality of ventilation holes 611 arranged at intervals, and the air flow generating member 62 is disposed adjacent to the ventilation holes 611 and also adjacent to a port where the polishing disc cover 61 is connected to a tool machine housing 63. Desirably, when the airflow generating member 62 rotates, air is introduced from the air holes 611 to dissipate heat, but for the following reasons: the ventilation holes 611 are arranged at intervals (as shown in fig. 2), and the airflow generating member 62 is excessively close to the ventilation holes 611, so that in practice, the ventilation holes 611 cannot generate the expected effect, when one of the ventilation holes 611 is air intake, the other ventilation hole 611 is connected to the air intake, and exhaust is generated, so that a short flow problem (also called short circulation) is generated, so that the air intake efficiency of the ventilation holes 611 is not expected, further, the heat dissipation effect of the airflow generating member 62 is limited to the eccentric block, and the eccentric block is connected with the electric motor 64 to lead out waste heat, but the shaft diameter of an axle connected with the eccentric block and the electric motor 64 is smaller, and the waste heat transmission speed is lower than the waste heat generation speed of the electric motor 64, so that the waste heat is stored continuously, and the feeling of a user holding the machine tool housing 63 is affected.

Furthermore, although a plurality of air inlet holes 631 are provided on the machine tool housing 63 in the conventional art, the air pressure difference generated in the machine tool housing 63 when the air flow generating member 62 rotates is used to draw the external air into the machine tool housing 63 from the air inlet holes 631 and generate the air flow. However, as can be seen from the foregoing, the air flow generating member 62 has a problem of poor efficiency, cannot generate suction force meeting the requirement, affects the air quantity entering from the air inlet holes 631, cannot effectively dissipate heat of the electric motor 64, and the condition of waste heat accumulation of the electric motor 64 is still serious. Furthermore, in order to make the air flow flowing in the machine tool housing 63 pass through the position of the electric motor 64, the air inlet holes 631 are not directly adjacent to the air flow generating element 62 at the position of the machine tool housing 63, that is, the air inlet holes 631 are at a certain distance from the air flow generating element 62, and the suction force is also attenuated by the distance, so that the air flow generating element 62 alone cannot generate a large air volume of air flow in the machine tool housing 63.

The only current implementation for solving the problem of heat accumulation in an electric polishing tool machine is to implement an active dust suction structure 71 on an electric polishing tool machine 70, as disclosed in fig. 3 or EP2946710B 1. As illustrated in fig. 3, the air inlet of the active dust suction structure 71 is an air inlet 721 formed on a polishing disc mask 72, and when the active dust suction structure 71 is implemented, the space in the polishing disc mask 72 generates a suction force, which is significantly greater than the suction force generated by an air flow generating member 73, and a large amount of air is sucked through a plurality of air inlet holes 741 on a machine tool housing 74, so that the large amount of air sucked through the air inlet holes 741 greatly helps to dissipate heat of an electric motor 75.

However, there is still a need for a solution to the problem of heat accumulation in the electric motor when the power tool is not equipped with the active dust suction structure.

Disclosure of Invention

The invention aims to solve the problem of air flow design of the shell of the conventional electric grinding tool.

The invention aims to solve the problem that the accumulated heat of an electric motor of a conventional electric grinding tool is not easy to discharge.

To achieve the above object, the present invention provides an electric polishing machine tool, which comprises an electric motor, an airflow generating member, and a housing. The air flow generating part rotates when the electric motor is started, the shell comprises a hollow shell, a motor shade which is positioned in the hollow shell and provides the electric motor, two partition plates which are positioned between one side wall of the motor shade and the hollow shell, at least one air outlet which faces the air flow generating part, at least one first air inlet which is formed on the hollow shell, and at least one second air inlet which is formed on the hollow shell and is separated from the first air inlet, the motor shade is divided into an air inlet part and an air outlet part which is communicated with the air inlet part by connecting lines of the two partition plates, the air outlet is close to the air outlet part, the first air inlet faces the air inlet part of the motor shade, and when the air flow generating part is started, a pressure difference is generated in the hollow shell close to the air inlet part of the motor shade so as to cause air inlet of the second air inlet.

In one embodiment, the motor mask includes a top surface connected to the side wall, and the two baffles are connected to the side wall and allow the air flow to pass through the top surface.

In one embodiment, two auxiliary partition boards matched with the two partition boards are arranged in the hollow shell.

In one embodiment, the electric polishing tool comprises a circuit board disposed in the housing and electrically connected to the electric motor, the housing has a holding portion with the electric motor, and a holding portion with the circuit board and extending from the holding portion, the first air inlet is disposed in the holding portion, and the second air inlet is disposed in the holding portion and faces the circuit board.

In one embodiment, the grasping portion includes a head section and a neck section extending from the head section and adjacent to the airflow generating member, and the first air inlet is adjacent to a location where the neck section is connected to the holding portion.

In an embodiment, the wind inlet position of the second air inlet is lower than the wind inlet position of the first air inlet.

In one embodiment, the housing is composed of a plurality of housing parts, and one of the housing parts is formed with the motor cover, the two partition plates, the air outlet, the first air inlet and the second air inlet.

In one embodiment, the air outlet is disposed along an edge of the motor mask.

In addition to the foregoing, the present invention also provides a housing of an electric polishing tool machine, comprising a hollow housing, a motor cover, two partitions, at least one air outlet, at least one first air inlet, and at least one second air inlet. The motor shade is positioned in the hollow shell, the two partition plates are positioned between the side wall of the motor shade and the hollow shell, and the two partition plates are positioned on two opposite sides of the motor shade. The air outlet is formed on one of the hollow shell and the outer edge of the motor shade, the first air inlet is formed on the hollow shell, the first air inlet and the air outlet are respectively positioned on two sides of the two clapboards, the first air inlet faces the motor shade and is close to one of the two clapboards, the second air inlet is formed on the hollow shell, the second air inlet and the first air inlet are positioned on the same side of the two clapboards, and the distance from the second air inlet to the air outlet is larger than that from the first air inlet to the air outlet.

In one embodiment, two auxiliary partition boards matched with the two partition boards are arranged in the hollow shell.

In an embodiment, the hollow housing is divided into a grasping portion and a holding portion extending from the grasping portion, the first air inlet is located at the grasping portion, and the second air inlet is located at the holding portion.

In one embodiment, the grasping portion includes a head section and a neck section extending from the head section, and the first air inlet is adjacent to a location where the neck section is connected to the grasping portion.

In an embodiment, the wind inlet position of the second air inlet is lower than the wind inlet position of the first air inlet.

In one embodiment, the hollow housing is formed by a plurality of housing pieces, one of which forms part of the hollow housing, the motor shroud, the two baffles, the air outlet, the first air inlet and the second air inlet.

In one embodiment, the air outlet is disposed along an edge of the motor mask.

Compared with the prior art, the invention has the following characteristics: in the invention, the first air inlet is acted by the air flow generating part firstly compared with the second air inlet, and pressure difference is generated at the air inlet part of the hollow shell close to the motor shade, so that air inlet of the second air inlet is caused, and the problems that air flow in the shell is generated by the suction force of the air flow generating part singly, and insufficient air flow is easy to generate and the heat dissipation in the shell is caused are particularly improved. According to the invention, the first air inlet and the second air inlet are used for carrying out air intake together, so that the interior of the shell can generate an atmospheric air flow, the heat exchange with the motor shade is increased, and the accumulated waste heat generated by the motor shade due to the operation of the electric motor is effectively brought out. In addition, the invention further enables the air flow to completely pass through the top surface of the motor shade through the two partition plates, so that the temperature rise of the part of the hollow shell which is held by a user is not severe any more, and the comfort level of the palm of the user during long-term holding and use is greatly increased.

Drawings

FIG. 1 is a schematic diagram of a first embodiment of a conventional electric grinding machine;

FIG. 2 is a schematic airflow diagram of a first embodiment of a conventional electric grinding machine;

FIG. 3 is a schematic diagram of a second embodiment of a conventional electric grinding machine;

FIG. 4 is a schematic view of an embodiment of the electric abrasive machine of the present invention;

FIG. 5 is an exploded view of one embodiment of the electric abrasive machine of the present invention;

FIG. 6 is a schematic top view of a partial structure of an embodiment of the electric abrasive machine of the present invention;

FIG. 7 is a schematic cross-sectional view of an embodiment of the electric abrasive machine of the present invention;

FIG. 8 is a schematic view of air flow intake for an embodiment of the electric abrasive machine of the present invention;

FIG. 9 is a schematic air flow diagram (I) of an embodiment of the electric abrasive machine of the present invention;

FIG. 10 is an enlarged schematic view of a partial structure of an embodiment of the electric abrasive machine of the present invention;

FIG. 11 is an enlarged view of a portion of an embodiment of the electric abrasive machine tool of the present invention;

FIG. 12 is a schematic air flow diagram (II) of an embodiment of the electric abrasive machine of the present invention.

[ Symbolic description ]

20: Electric grinding tool machine

21: Shell body

211: Hollow shell

212: Motor shade

213: Partition board

214: Air outlet

215: First air inlet

216: Second air inlet

217: Shell member

218: Ventilation gap

219: Side wall

220: Top surface

221: Air inlet part

222: Air outlet part

223: Grasping part

224: Holding part

225: Head section

226: Neck section

228: Central axis

229: Auxiliary partition board

23: Electric motor

24: Airflow generating member

241: Substrate board

242: Fan blade

25: Grinding disc

251: Flour with a plurality of grooves

261: Air flow

262: Air flow

27: Circuit board

28: Eccentric block

281: First part

282: Second part

29: Abrasive disk mask

291: Mask body

292: Group interface

293: Release port

294: Drainage segment

295: Arc-shaped steering section

296: Air outlet section

297: Inclined plane

30: Air flow temporary storage area

40: Palm center measuring point

41: Finger-holding measuring point

42: Distance of

43: Distance of

44: Distance of

50: Air flow

60: Electric grinding tool machine

61: Abrasive disk mask

611: Vent hole

62: Airflow generating member

63: Machine tool housing

631: Air inlet hole

64: Electric motor

70: Electric grinding tool machine

71: Active dust collection structure

72: Abrasive disk mask

721: Suction inlet

73: Airflow generating member

74: Machine tool housing

741: Air inlet hole

75: Electric motor

Detailed Description

The detailed description and the technical content of the invention are now as follows in conjunction with the accompanying drawings:

Referring to fig. 4 to 7, the present invention provides an electric polishing machine tool 20, which includes a housing 21, an electric motor 23, an airflow generating member 24, and a polishing plate 25. The housing 21 includes a hollow housing 211, a motor cover 212 providing the electric motor 23, two baffles 213, at least one air outlet 214, at least one first air inlet 215, and at least one second air inlet 216. The hollow housing 211 may be formed by assembling a plurality of housing parts 217, the motor cover 212 is disposed in the hollow housing 211, and the motor cover 212 may be a directly molded part of one of the housing parts 217. The motor cover 212 of the present invention does not abut against the inner wall of the hollow housing 211, so that the housing 21 forms a ventilation gap 218 between the hollow housing 211 and the motor cover 212. Also, the two baffles 213 are located between the side wall of the motor shroud 212 and the hollow housing 211, more specifically, the two baffles 213 are located on opposite sides of the motor shroud 212, the two baffles 213 are located at the vent gap 218, but it is understood that the two baffles 213 do not completely divide the vent gap 218 into two areas, and the two baffles 213 are only used to direct the airflow to the non-baffled portions of the two baffles 213. Further, the motor cover 212 includes a sidewall 219 and a top surface 220 connected to the sidewall 219, and the two baffles 213 are connected to the sidewall 219 and allow air flow through the top surface 220. In addition, the connection line between the two separators 213 divides the motor mask 212 into an air inlet portion 221 and an air outlet portion 222, and the air inlet portion 221 is still in communication with the air outlet portion 222.

On the other hand, referring to fig. 6 and 7, in the present invention, the air outlet 214 faces the air flow generating member 24, and the air outlet 214 is formed on one of the outer edges of the hollow housing 211 and the motor cover 212. The air outlet 214 is disposed near the air outlet portion 222 of the motor mask 212, and the first air inlet 215 corresponds to the air inlet portion 221 of the motor mask 212. That is, the air outlet 214 and the first air inlet 215 are respectively located at two sides of the two partitions 213. The gas outlet 214 is an outlet of the gas flow in the housing 21, and the gas flow generating member 24 attracts the gas in the hollow housing 211 from the gas outlet 214, so that the gas in the housing 21 flows to generate a gas flow. In one embodiment, the air outlet 214 is disposed along an edge of the motor mask 212.

Referring back to fig. 5 and 6, the first air inlet 215 is formed on the hollow housing 211 and faces the motor cover 212, and the first air inlet 215 is close to one of the two baffles 213. The second air inlet 216 and the first air inlet 215 are located on the same side of the two partition plates 213, the second air inlet 216 and the first air inlet 215 are formed on the hollow housing 211 at a distance from each other, and the distance from the second air inlet 216 to the air outlet 214 is greater than the distance from the first air inlet 215 to the air outlet 214. As shown in fig. 6, 8 and 9, in the implementation of the present invention, the first air inlet 215 is closer to the air outlet 214, and is acted on by the airflow generating member 24 earlier than the second air inlet 216, so that the first air inlet 215 generates air intake (as indicated by 261 in fig. 8), and the air intake of the first air inlet 215 generates a pressure difference in the middle shell housing 211 near the air intake portion 221 of the motor mask 212, and the air pressure difference acts on the second air inlet 216, so as to cause air intake of the second air inlet 216 (as indicated by 262 in fig. 8). Therefore, the problem that the air flow in the past shell is insufficient to correspond to the heat dissipation in the shell is solved by specifically improving the generation of the air flow by the suction force of the air flow generating part. Referring back to fig. 7 to 9, the first air inlet 215 and the second air inlet 216 of the present invention can generate an air flow inside the housing 21, and increase the heat exchange with the motor cover 212, so as to effectively take out the accumulated waste heat generated by the motor cover 212 due to the operation of the electric motor 23. In addition, the present invention further makes the air flow completely pass through the top surface 220 of the motor mask 212 through the two baffles 213, so that the waste heat on the motor mask 212 is effectively discharged, and the comfort of the palm of the user during long-term holding and use is greatly increased.

Referring to tables one and two, a comparative table of the temperature rise of the electric polishing tool 20 of the present invention (referred to as the present invention in the table), a conventional electric polishing tool without an active dust suction structure (referred to as the conventional dust suction structure in the table), and an electric polishing tool with an active dust suction structure (referred to as the conventional dust suction structure in the table) is shown. The temperature measurement point is the palm grip of the user (40 as indicated in fig. 4), and the set conditions are 180W load, sand paper #80, and 6 inch abrasive disk. The basic conditions for Table two are the same as those for Table one, except that the temperature measurement point is the user's finger grip (41 as indicated in FIG. 4).

List one

Watch II

From the first and second tables, it can be understood that when the conventional cleaner is operated for 15 minutes, the temperature rises of the palm center measuring point and the finger grip measuring point are obvious, and the external surface of the machine tool is measured to have such high temperature, so that the internal temperature of the machine tool can be expected to be higher, and the problem of waste heat accumulation caused by insufficient air flow formed in the shell of the machine tool due to heat dissipation of the internal components of the shell is highlighted. In contrast, in the electric polishing tool 20 of the present invention, there is no severe temperature rise during a plurality of detection times, and it is apparent that the design of the first air inlet 215 and the second air inlet 216 in this case achieves the purpose of air intake in a coordinated manner, so that the air flow flowing in the housing 21 is increased, and the waste heat generated by the operation of the electric motor 23 is rapidly brought out. On the other hand, the temperature change of the palm center measuring point is more remarkable that the two baffles 213 of the present invention make the air flow completely pass through the top surface 220 of the motor mask 212, so that the temperature rise of the portion of the hollow housing 211 which is held by the user is not severe, and the comfort of the palm of the user during long-term holding and use is greatly increased.

Further, comparing the temperature of the present invention with the temperature of the conventional dust collector at the operation time of a plurality of machine tools, it is obvious that the temperature of the palm measuring point and the finger holding measuring point is better than the performance of the conventional dust collector in the part of the finger holding measuring point (table two) besides the performance of the conventional dust collector under the condition that an active dust collecting structure is not installed in the present invention. Accordingly, the present invention can effectively solve the heat accumulation problem of the electric motor 23 which is not solved by the conventional structure.

Referring back to fig. 4, 5 and 7, in one embodiment, the electric polishing tool 20 includes a circuit board 27, and the circuit board 27 is disposed in the housing 21 and electrically connected to the electric motor 23. The housing 21 can be distinguished into a grip portion 223 in which the electric motor 23 is mounted and a grip portion 224 in which the circuit board 27 is mounted and which extends from the grip portion 223. The first air inlet 215 is located at the grasping portion 223, and the second air inlet 216 is located at the holding portion 224 and faces the circuit board 27. Further, the grip 223 may include a head section 225, and a neck section 226 extending from the head section 225 and proximate to the airflow-generating member 24. The head section 225 will face a palm of the user when the user is grasping, and the neck section 226 provides finger grip when the user is grasping. Further, the first air inlet 215 is near the location where the neck section 226 connects with the grip 224.

Referring back to fig. 5, in one embodiment, the hollow housing 211 is formed by the housing members 217, and one of the housing members 217 forms a part of the hollow housing 211, the motor cover 212, the two partition plates 213, the air outlet 214, the first air inlet 215 and the second air inlet 216.

Referring back to fig. 6, the first air inlet 215 of the present invention may be implemented in a plurality of ways, and the plurality of first air inlets 215 may be symmetrically disposed on the left and right sides of the housing 21 along a central axis 228 of the housing 21.

Referring back to fig. 9, in one embodiment, the wind entering position of the second air inlet 216 is lower than the wind entering position of the first air inlet 215. Referring to fig. 6, in one embodiment, two auxiliary partitions 229 are disposed in the hollow housing 211 and cooperate with the two partitions 213.

Referring to fig. 5, the electric polishing machine 20 of the present invention includes an eccentric block 28 connected to the electric motor 23, and a polishing disc mask 29. The eccentric block 28 has a stepped shape and has a first portion 281 and a second portion 282 located below the first portion 281 and offset from the axis of the first portion 281. The air flow generating member 24 is attached to the eccentric block 28 and is located in the space defined by the polishing disc mask 29, and further, the air flow generating member 24 is attached to the second portion 282 of the eccentric block 28, and the bottom edge of the air flow generating member 24 is equal to or slightly higher than the bottom edge of the second portion 282 of the eccentric block 28. The airflow generating member 24 includes a base plate 241 and fan blades 242 disposed on the base plate 241, the fan blades 242 are identical in shape, the fan blades 242 are disposed on a side surface of the base plate 241 facing the eccentric block 28, and the fan blades 242 are disposed at intervals and are arranged on the base plate 241 in a circle. In one embodiment, to more smoothly introduce a large amount of gas into the housing 21, the gas flow generating member 24 is disposed in the space defined by the platen mask 29 based on the following conditions: the distance between the top edge of each of the blades 242 and the housing 21 (42 as shown in fig. 10) is greater than 50% of the longitudinal height of each of the blades 242, the distance between the outer edge of each of the blades 242 and the polishing disk shroud 29 (43 as shown in fig. 10) is greater than 50% of the radial width of each of the blades 242, and the outer diameter of the airflow generating member 24 is greater than the distance from the air outlet 214 to the center of the motor shroud 212. Based on the above conditions, in the present embodiment, the air flow generating member 24 is not closely attached to the housing 21 and the polishing disc mask 29, but an air flow temporary storage area 30 is generated, and the air flow temporary storage area 30 can keep the air guiding effect of the air flow generating member 24 smooth.

Referring to fig. 10 to 12, the polishing disc cover 29 is assembled with the housing 21 and houses the air flow generating member 24 therein. The polishing pad mask 29 includes a mask body 291, an interface 292 formed at one end of the mask body 291, and a release opening 293 formed at the other end of the mask body 291. The polishing disk mask 29 does not have the set of ports 292 and the vent ports other than the release port 293, and the set of ports 292 and the release port 293 are coaxially disposed, i.e., the set of ports 292 and the release port 293 are disposed opposite to each other. In order to prevent the air flow from striking the surface of the polishing disk 25 by mistake when the air flows out from the gap between the polishing disk mask 29 and the polishing disk 25, turbulence is generated, which affects the overall efficiency of the air flow. Referring to fig. 11, in one embodiment, the polishing disc mask 29 has a drainage section 294, an arc turning section 295, and an air outlet section 296 in order from the set of openings 292 toward the release opening 293. The drainage section 294 is connected with the inner wall surface of the mask body 291 close to the release opening 293 without any break, and the drainage section 294 and the inner wall surface of the mask body 291 close to the release opening 293 together form a flat surface. The arc-shaped turning section 295 is used as a connector between the air-guiding section 294 and the air-out section 296, the slopes of the air-out section 296 and the air-guiding section 294 are different, and further, the included angle between the air-out section 296 and the air-guiding section 294 is larger than 90 degrees. Furthermore, the air-out segment 296 may be parallel to the side 251 of the polishing disk 25 facing the polishing disk mask 29. As described above, when the air flow (50 as shown in FIG. 12) passes through the discharge port 293, coanda effect (also known as Kangar effect or coanda effect) is generated by the wall surface of the discharge port 293 (i.e. the drainage section 294, the curved turning section 295, and the air outlet section 296); Effect), change flow direction, and finally exhaust along the outlet segment 296. Accordingly, the guiding design on the release opening 293 can prevent the air flow from being discharged toward the polishing disk 25, thereby avoiding the turbulence caused by the direct impact on the polishing disk 25, and affecting the overall efficiency of the air flow.

With reference to fig. 10 and 11, in one embodiment, the level of the relief opening 293 is equal to or lower than the level of the substrate 241 of the airflow generating member 24 in the polishing disc mask 29. The aperture of the release opening 293 is larger than that of the set of openings 292, and the polishing disc cover 29 is in a horn shape, so that the flow rate of the air flow entering the polishing disc cover 29 from the air outlet 214 is slowed down, and turbulence in the polishing disc cover 29 due to the excessively high flow rate of the air flow is avoided. In one embodiment, the distance (e.g., 44 shown in FIG. 10) between the release opening 293 and each of the plurality of blades 242 is greater than the diameter of each of the plurality of blades 242. In addition, the mask body 291 has a slope 297 between the set of openings 292 and the release opening 293, the slope 297 is connected to the drainage section 294 of the release opening 293, and the slope of the drainage section 294 is the same as the slope of the slope 297. On the other hand, in one embodiment, the distance from the outer edge of the air outlet 214 to the center of the motor mask 212 (as indicated at 45 in FIG. 6) is smaller than the outer diameter of the airflow generating member 24.

Claims (15)

1. An electric abrasive machine tool, comprising:

an electric motor;

an airflow generating member which rotates when the electric motor is started; and

The shell comprises a hollow shell, a motor shade, two partition plates, at least one air outlet, at least one first air inlet and at least one second air inlet, wherein the motor shade is positioned in the hollow shell and is used for providing the electric motor, the two partition plates are positioned between one side wall of the motor shade and the hollow shell, the air outlet is arranged opposite to the air flow generating part, the first air inlet is formed on the hollow shell, the second air inlet is formed on the hollow shell and is spaced from the first air inlet, the motor shade is divided into an air inlet part and an air outlet part communicated with the air inlet part by connecting wires of the two partition plates, the air outlet is close to the air outlet part, the first air inlet faces the air inlet part of the motor shade, and when the air flow generating part is started, a pressure difference is generated at the position, close to the air inlet part of the motor shade, in the hollow shell, so that air inlet of the second air inlet is caused.

2. The electric power tool of claim 1, wherein the motor housing includes a top surface connected to the sidewall, the two baffles being connected to the sidewall and allowing the air flow to pass through the top surface.

3. An electric grinding machine as claimed in claim 1 or 2, characterized in that two auxiliary partitions are provided in the hollow housing, which cooperate with the two partitions.

4. The electric power tool according to claim 1 or 2, wherein the electric power tool comprises a circuit board disposed in the housing and electrically connected to the electric motor, the housing having a grip portion with the electric motor mounted thereon, and a grip portion with the circuit board mounted thereon and extending from the grip portion, the first air inlet being located in the grip portion, the second air inlet being located in the grip portion and facing the circuit board.

5. The power tool of claim 4, wherein the handle portion includes a head section and a neck section extending from the head section and adjacent the airflow generating member, the first air inlet being adjacent a location where the neck section connects with the grip portion.

6. The electric power tool of claim 4, wherein the second air inlet is positioned at a lower wind position than the first air inlet.

7. The electric power tool of claim 1, wherein the housing is comprised of a plurality of housing members, one of the plurality of housing members being formed with the motor shroud, the two partitions, the air outlet, the first air inlet, and the second air inlet.

8. The electric grinding tool machine of claim 1 or 7, wherein the air outlet is provided along an edge of the motor shroud.

9. A housing for an electric abrasive machine tool, comprising:

A hollow housing;

a motor shield located within the hollow housing;

Two partition plates positioned between the motor shade side wall and the hollow shell and positioned on two opposite sides of the motor shade;

at least one air outlet formed on one of the hollow housing and the motor shade outer edge;

at least one first air inlet formed on the hollow shell, wherein the first air inlet and the air outlet are respectively positioned at two sides of the two partition boards, and the first air inlet faces the motor shade and is close to one of the two partition boards; and

And the second air inlet is formed on the hollow shell and is positioned on the same side of the two partition plates as the first air inlet, and the distance from the second air inlet to the air outlet is larger than that from the first air inlet to the air outlet.

10. The housing of an electric power tool of claim 9, wherein two auxiliary partitions are provided in the hollow housing that mate with the two partitions.

11. The housing of claim 10, wherein the hollow housing is divided into a grip portion and a grip portion extending from the grip portion, the first air inlet being located in the grip portion and the second air inlet being located in the grip portion.

12. The housing of claim 11, wherein the handle portion includes a head section and a neck section extending from the head section, the first air inlet being proximate a location where the neck section connects with the grip portion.

13. The housing of an electric power tool machine of claim 12, wherein the second air inlet has a lower wind-in position than the first air inlet.

14. The housing of an electric power tool of claim 9, wherein the hollow housing is formed from a plurality of housing pieces, one of the plurality of housing pieces forming part of the hollow housing, the motor shroud, the two baffles, the air outlet, the first air inlet, and the second air inlet.

15. The housing of an electric power tool of claim 9, wherein the air outlet is disposed along an edge of the motor shroud.