Grinding machine with reduced heat emission

Abstract

A grinding tool machine with reduced heat emission includes a housing and a driving assembly. The housing is divided into a head portion and a body portion. The housing includes a plurality of housing members. The housing has an air inlet provided on the body portion and an air outlet provided on the head portion away from the body portion. A motor cover is formed on the head portion. The motor cover does not contact the housing members to form an air flow passage. The driving assembly includes a circuit board provided on the housing, a motor provided in the motor cover, and an air flow generator synchronously rotating with the motor. The air flow generator generates a first heat dissipation air flow passing through the air flow passage and dissipating heat from the circuit board and the head portion when the air flow generator rotates. The air flow generator also generates a second heat dissipation air flow dissipating heat from a side of the motor facing the air flow generator.

Description

TECHNICAL FIELD

[0001] The present invention relates to a grinding tool machine with reduced heat emission, and more particularly to a grinding tool machine with a heat dissipation airflow passing through the machine housing to reduce heat emission. BACKGROUND

[0002] However, the conventional airflow can only flow towards the side of the motor facing the fan, so that the side of the motor not facing the fan cannot obtain heat dissipation, causing uneven heat dissipation of the motor, and the heat energy on the motor continues to accumulate and is transferred to the motor housing.

[0003] Further, the conventional motor is usually arranged at a position corresponding to the position where a user holds the grinding tool machine, and the conventional grinding tool machine is usually closed to prevent dust from flowing into the tool machine, so that the gas in the tool machine cannot flow. When the motor is used for a long time, a large amount of heat energy is easily accumulated on the side of the motor not facing the fan, and is transferred to the grinding tool machine housing through heat radiation, causing the grinding tool machine housing to heat up and be not easy to hold.

[0004] To solve the problem of poor heat dissipation in the conventional grinding tool machine, US Patent No. US 7,270,598 discloses a conventional grinding tool machine that uses external air to dissipate heat into the grinding tool machine. Specifically, when the dust-containing gas generated by grinding is sucked through the dust suction pipe, the gas pressure in the tool machine changes, so that external air enters the tool machine through the air inlet and enters the dust suction pipe. The external air flows towards the dust suction pipe, passes through the motor and dissipates heat from the motor. However, the flow direction of the external air flowing into the tool machine is different from the flow direction of the dust-containing gas, so that the external air and the dust-containing gas easily interfere with each other and generate turbulence. Furthermore, when the dust suction pipe sucks dust, the dust suction gas must pass through the space in the tool machine and enter the dust suction pipe, so that the grinding tool machine cannot prevent dust in the dust suction gas from flowing into the grinding tool machine, causing dust to accumulate on the motor and other electronic components and affecting the operation of the components.

[0005] CN 110270930A and US 9,408,513B, etc. do not use the conventional heat dissipation mechanism for heat dissipation, that is, the grinding tool machine disclosed in CN 110270930A and US 9,408,513B, etc. is not provided with an air inlet for external air to enter, but the grinding tool machine shell is closed to reduce the problem of dust accumulation inside the tool machine. Further, CN 110270930A and US 9,408,513B, etc. use a motor and a grinding tool machine shell to be spaced apart, thereby reducing the heat energy accumulated by the motor and transferred to the grinding tool machine shell. However, the grinding tool machine of CN 110270930A and US 9,408,513B, etc. can only partially cool the motor, so that the motor still has uneven cooling. The cooling scheme of the motor not in contact with the grinding tool machine shell can only reduce the speed of heat transfer from the motor to the shell, and cannot specifically solve the problem of heat energy accumulation on the motor and heat transfer from the motor to the shell. Moreover, since the conventional fan cannot introduce external air into the tool machine interior, the fan can only drive the gas inside the tool machine to form the air flow. When the conventional grinding tool machine is used for a long time, the heat accumulated on the motor and circuit board inside the grinding tool machine will cause the temperature of the gas inside the tool machine to rise, and the air flow generated by the fan will also be heated and cannot provide good cooling for the motor, so that the tool machine shell will still receive heat energy from the motor and become hot. In addition, since the conventional grinding tool machine is a closed structure, external air cannot flow into the tool machine interior to cool the air inside the tool machine, so that the grinding tool machine shell may be affected by the internal air and have the possibility of rising in temperature, which is not conducive to the user to hold. SUMMARY

[0006] The main purpose of the present application is to solve the problem that the conventional heat dissipation mechanism for introducing external air is easy to cause dust to enter the interior of the grinding tool machine.

[0007] Another purpose of the present application is to solve the problem that the conventional grinding tool machine with a closed shell cannot specifically reduce the problem of the tool machine shell becoming hot.

[0008] To achieve the above object, the present application provides a grinding tool machine with reduced heat emission, comprising a machine housing and a driving assembly. The machine housing is divided into a head portion and a body portion, and is composed of at least two housing parts. The machine housing has an air inlet formed in the body portion and an air outlet formed in the head portion away from the body portion. The machine housing is provided with a motor cover at the head portion, and the motor cover is open at one end facing a grinding part. There is a gap between the motor cover and the housing parts, so that an air flow passage is formed in the machine housing through the air inlet and the air outlet. The driving assembly comprises a circuit board arranged in the machine housing, a motor arranged in the motor cover and connected to the circuit board to drive the grinding part to rotate, and an air flow generator arranged in the motor cover and synchronously rotating with the motor. The air flow generator rotates to generate a first heat dissipation air flow in the machine housing through the air flow passage to dissipate heat from the circuit board and the head portion of the machine housing, and a second heat dissipation air flow to dissipate heat from the side of the motor facing the air flow generator.

[0009] In one embodiment, the grinding tool machine comprises a wind guide arranged in the machine housing and located in the air flow passage. The wind guide has a wind receiving end and an air outlet end higher than the wind receiving end.

[0010] In one embodiment, the motor cover is in the shape of a barrel, and the wind guide forms a main guide surface along the edge of the motor cover and two auxiliary guide surfaces arranged on both sides of the main guide surface and having different flow directions.

[0011] In one embodiment, the wind guide extends on both sides into the gap between the side edge of the motor cover and the inner wall of the head portion, and forms a guide channel. The entrance of the guide channel is higher than the exit.

[0012] In one embodiment, the wind guide is located at the junction of the body portion and the head portion.

[0013] In one embodiment, the motor comprises an output shaft and a seat for connecting the grinding part and driven by the output shaft. The air flow generator comprises a mounting seat connected to the seat, an end plate extending from the mounting seat, and a plurality of fan blades arranged on the side of the end plate facing the motor cover.

[0014] In one embodiment, the fan blades stand on the end plate.

[0015] In one embodiment, the seat comprises two misaligned blocks, and the mounting seat has a receiving space formed to match the two blocks.

[0016] In one embodiment, the mounting seat is provided with at least two limiting arms for limiting the disengagement of the seat.

[0017] In one embodiment, the accommodating space extends through both ends of the mounting base, and the mounting base is provided with a limiting wall at the end of the accommodating space away from the fan blades. The limiting wall and the two limiting arms together restrict the support.

[0018] In one embodiment, the grinding tool includes an end cap located at the open end of the motor housing.

[0019] In one embodiment, the housings are divided into a lower housing and an upper housing. The lower housing is assembled with the motor housing, and the upper housing is not in contact with the motor housing and together with the lower housing forms the airflow channel.

[0020] In one embodiment, the grinding tool includes a dust cover assembled with the housing and located at the head, and a dust collection pipe disposed on the dust cover.

[0021] In one embodiment, the circuit board is disposed on the body, and the grinding tool includes a heat sink disposed on the body and capable of dissipating heat from the circuit board. The lower housing has a positioning groove for placing the heat sink therein, and the air inlet is formed in the positioning groove.

[0022] In one embodiment, the air inlet is composed of a plurality of strip-shaped holes.

[0023] As disclosed above, compared with conventional technology, the present invention has the following features: In addition to using conventional heat dissipation mechanisms to dissipate heat on one side of the motor, after the housing is assembled, the present invention ensures that the motor cover and the housing parts are not in contact to form the airflow channel within the housing, so that when the airflow generating component rotates, the first heat dissipation airflow can flow through the airflow channel to dissipate heat on the circuit board and the head of the housing. Attached Figure Description

[0024] Figure 1 This is a three-dimensional schematic diagram of the first embodiment of the present invention;

[0025] Figure 2 This is a partial structural exploded view of the first embodiment of the present invention;

[0026] Figure 3 This is an exploded cross-sectional view of the first embodiment of the present invention;

[0027] Figure 4 This is a top view schematic diagram of some components in the first embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of airflow according to the first embodiment of the present invention (I);

[0029] Figure 6 This is a schematic diagram (II) of the airflow of the first embodiment of the present invention;

[0030] Figure 7 This is a three-dimensional schematic diagram of the second embodiment of the present invention;

[0031] Figure 8 This is an exploded three-dimensional structural diagram of the second embodiment of the present invention;

[0032] Figure 9 This is a schematic diagram of airflow according to the second embodiment of the present invention (I);

[0033] Figure 10 This is a schematic diagram of airflow according to the second embodiment of the present invention (II).

[0034] [Symbol Explanation]

[0035] 10: Grinding machine tools

[0036] 11: Chassis

[0037] 111: Head

[0038] 112: Body

[0039] 113: Shell

[0040] 115: Air Inlet

[0041] 116: Vent

[0042] 117: Motor housing

[0043] 118: Airflow Channel

[0044] 119: Assembly opening

[0045] 120: Positioning slot

[0046] 121: Strip-shaped pores

[0047] 122: Assembly Section

[0048] 123: Extension

[0049] 124: Operating the pressure plate

[0050] 125: Assembly hole

[0051] 126: Assembly Structure

[0052] 127: Lower shell

[0053] 128: Upper shell

[0054] 14: Driver Components

[0055] 140: Ontology

[0056] 141: Circuit Board

[0057] 142: Motor

[0058] 143: Airflow generating component

[0059] 144: Output shaft

[0060] 145: Power Line

[0061] 146: Support

[0062] 147: Mounting bracket

[0063] 148: End plate

[0064] 149: Fan blade

[0065] 150: Storage space

[0066] 151: Block

[0067] 152: Limiting Arm

[0068] 153: Limiting Wall

[0069] 16: Air guide component

[0070] 161: Windward end

[0071] 162: Air outlet end

[0072] 163: Dominant Surface

[0073] 164: Auxiliary guidance surface

[0074] 165: Guiding Path

[0075] 166: Entrance

[0076] 167: Exports

[0077] 168: Cable Crossover Port

[0078] 18: Dustproof cover

[0079] 19: Dust collection pipe

[0080] 21: End Cap

[0081] 22: Heat sink

[0082] 221: Substrate

[0083] 222: Heat dissipation fins

[0084] 30: Grinding parts

[0085] 60: First heat dissipation airflow

[0086] 70: Second heat dissipation airflow

[0087] 80: Suction airflow Detailed Implementation

[0088] The detailed description and technical content of this invention are as follows, in conjunction with the accompanying drawings:

[0089] Please see Figures 1 to 6 The present invention provides a grinding tool 10 that reduces housing overheating. The grinding tool 10 is used in conjunction with a grinding element 30, and includes a housing 11 and a drive assembly 14. The housing 11 is divided into a head 111 and a body 112. Specifically, the head 111 of the housing 11 is a gripping area for the user's hand when operating the grinding tool 10, and the body 112 of the housing 11 is a place for the user's wrist or arm to rest against when operating the grinding tool 10. The housing 11 is composed of at least two shell parts 113, which form the outer shape of the grinding tool 10. The housing 11 has an air inlet 115 formed on the body 112 and an air outlet 116 formed on the head 111 away from the body 112. The air inlet 115 and the air outlet 116 are located in positions that will not be obstructed by the user when operating the grinding tool 10. Furthermore, the housing 11 has a motor cover 117 on the head 111, which is open on the side facing the grinding workpiece 30. More specifically, after the shell parts 113 are assembled, the motor cover 117 does not contact the shell parts 113, resulting in a gap that forms an airflow channel 118 connecting the air inlet 115 and the air outlet 116 within the housing 11.

[0090] Continuing on the above, the drive assembly 14 includes a circuit board 141 disposed within the housing 11, a motor 142 electrically connected to the circuit board 141, and an airflow generator 143 that rotates synchronously with the motor 142. Specifically, the motor 142 is inserted through the open side of the motor housing 117 and is partially shielded by the motor housing 117. The airflow generator 143 is located on the side of the motor 142 facing the grinding piece 30. After assembly, the airflow generator 143 shields the open end of the motor housing 117, so that the unshielded end of the motor 142 faces the airflow generator 143. Furthermore, the motor 142 starts after receiving power from the circuit board 141, causing an output shaft 144 of the motor 142 to rotate, thereby driving the grinding piece 30 to perform grinding operations. In addition, when the motor 142 is operating, it also causes the airflow generating component 143 to rotate synchronously. When the airflow generating component 143 rotates, it generates a first cooling airflow 60 and a second cooling airflow 70.

[0091] Specifically, when the airflow generator 143 rotates, it causes a change in gas pressure within the head 111, causing external air to enter through the air inlet 115 and transform into the first cooling airflow 60. This first cooling airflow 60 enters the housing 11 and flows along the airflow channel 118. Because the motor 142 is shielded by the motor housing 117, the first cooling airflow 60 cannot flow into the motor 142 and instead flows along the inner wall of the motor housing 117 and the head 111. Subsequently, the first cooling airflow 60 is guided by the airflow generator 143 and discharged through the air outlet 116. During its flow, the first cooling airflow 60 exchanges heat with the circuit board 141 and with the motor housing 117 as it flows through the head 111, thereby carrying away the heat accumulated on the circuit board 141 and reducing the transfer of heat from the motor 142 to the motor housing 117. On the other hand, when the airflow generator 143 rotates, it causes a change in gas pressure on the side of the motor 142 facing the airflow generator 143, thereby generating the second cooling airflow 70. The second cooling airflow 70 exchanges heat with the side of the motor 142 facing the airflow generator 143, and the second cooling airflow 70 is guided by the airflow generator 143 during its flow and discharged to the outside through the air outlet 116. In this way, the second cooling airflow 70 can provide heat dissipation for the side of the motor 142 facing the airflow generator 143, and allow the heat of the side of the motor 142 facing the airflow generator 143 to be discharged outside the housing 11.

[0092] Continuing from the above, in addition to the second cooling airflow 70 dissipating heat from the side of the motor 142 facing the airflow generating component 143, the present invention also utilizes the fact that after the housing 11 is assembled, the motor cover 117 does not contact the housing components 113, thereby forming the airflow channel 118. This allows the first cooling airflow 60 to flow through the airflow channel 118 and cause airflow changes within the housing 11, thereby reducing the heat radiation from the circuit board and motor to the housing caused by poor internal air circulation in conventional grinding tools, and simultaneously solving the problem of uneven heat dissipation in conventional grinding tools. Furthermore, when the first cooling airflow 60 flows through the airflow channel 118, the motor 142 is shielded by the motor housing 117, preventing the first cooling airflow 60 from flowing into the motor 142. Instead, it flows along the surface of the motor housing 117 and the inner wall of the head 111, thereby allowing the first cooling airflow 60 to exchange heat between the motor housing 117 and the head 111 and reducing the amount of dust in the first cooling airflow 60 flowing into the motor 142. In addition, when the first cooling airflow 60 flows through the housing 11, in addition to dissipating heat from the motor 142, the first cooling airflow 60 can also simultaneously exchange heat with the circuit board 141. During its flow, the first cooling airflow 60 carries away the heat accumulated on the circuit board 141, reducing the transfer of heat from the circuit board 141 to the housing 11, thereby preventing the housing 11 from overheating.

[0093] In one embodiment, please refer to Figures 2 to 8 The grinding tool 10 includes an air guide 16 disposed in the housing 11. The air guide 16 is located on the airflow channel 118 to receive the first heat dissipation airflow 60 from the body 112. The air guide 16 has a receiving end 161 and an air outlet 162. The air outlet 162 is higher than the receiving end 161. The air outlet 162 and the receiving end 161 guide the first heat dissipation airflow 60 to flow along the surface of the air guide 16. Specifically, the air guide 16 is disposed on the side of the motor housing 117 facing the body 112 and located at the junction of the body 112 and the head 111. The motor housing 117 is cylindrical, and the air guide 16 is located at the edge of the motor housing 117 and is disposed at least along the semicircle of the motor housing 117. The air guide 16 forms a main guiding surface 163 and two auxiliary guiding surfaces 164. The two auxiliary guiding surfaces 164 are respectively disposed on both sides of the main guiding surface 163 and extend from the main guiding surface 163 toward the gap between the side of the motor housing 117 and the inner wall of the head 111. The airflow guiding direction of the two auxiliary guiding surfaces 164 is the same as that of the main guiding surface. The airflow guidance directions of 163 are different. Specifically, the first heat dissipation airflow 60 guided by the main guiding surface 163 flows to the part of the airflow channel 118 located between the top of the motor cover 117 and the shell parts 113, so that part of the first heat dissipation airflow 60 exchanges heat with the part of the head 111 that contacts the user's palm. The two auxiliary guiding surfaces 164 respectively guide part of the first heat dissipation airflow 60 into the part of the airflow channel 118 located between the side of the motor cover 117 and the shell parts 113, so that part of the first heat dissipation airflow 60 exchanges heat with the part of the head 111 that is gripped by the user's fingers.

[0094] Continuing from the above, the air guide 16 extends into the sides of the motor housing 117 on both sides and contacts the inner wall of the head 111 to form a guide channel 165. In fact, the guide channel 165 is implemented by a groove-shaped structure on the air guide 16, and the inner wall of the head 11 closes one side of the groove-shaped structure, so that the head 111 and the air guide 16 jointly define the guide channel 165. The guide channel 165 guides a portion of the first cooling airflow 60 located in the airflow channel 118. An inlet 166 of the guide channel 165 connects to the main guide surface 163 and receives a portion of the first cooling airflow 60 from the main guide surface 163. An outlet 167 of the guide channel 165 is lower than the inlet 166 of the guide channel 165 to guide a portion of the first cooling airflow 60 toward the outlet 116. Furthermore, in this embodiment, the guide channel 165 is formed jointly by the air guide 16 and the upper housing 128. In other embodiments, the guide channel 165 may be formed by the air guide 16. In addition, in one embodiment, the air guide 16 forms a cable passage 168 on the main guide surface 163, and the cable passage 168 provides a power line 145 connecting the motor 142 and the circuit board 141 through which a cable passes.

[0095] On the other hand, please refer to the following: Figures 2 to 6In one embodiment, the motor 142 further includes a body 140 connected to the output shaft 144 and a bearing 146 connected to the grinding element 30 and driven by the output shaft 144. The body 140 is what those skilled in the art would call a stator and rotor. The body 140 is electrically connected to the circuit board 141 to drive the output shaft 144 to rotate. The bearing 146 is connected to the side of the output shaft 144 that does not face the body 140. The bearing 146 is connected to the airflow generating element 143. When the motor 142 is started, the bearing 146 is driven by the output shaft 144, causing the airflow generating element 143 and the grinding element 30 to rotate accordingly. In one embodiment, after the airflow generator 143 and the support 146 are assembled, the airflow generator 143 is positioned sideways to face the air outlet 116. After the airflow generator 143 rotates, it guides the first cooling airflow 60 and the second cooling airflow 70 to flow toward the air outlet 116. Specifically, the airflow generator 143 has a mounting base 147 connected to the support 146, an end plate 148 extending from the mounting base 147, and a plurality of fan blades 149 disposed on the end plate 148. The end plate 148 is located on the side of the mounting base 147 facing the motor 142. The fan blades 149 are located on the end plate 148 and face the motor 142. In one embodiment, the fan blades 149 are connected to the end plate 148 on the side facing the end plate 148, while the fan blades 149 on the side not facing the end plate 148 extend away from the end plate 148, so that the fan blades 149 are upright on the end plate 148. During the rotation of the airflow generator 143, the fan blades 149 face the air outlet 116 laterally. After the airflow generator 143 rotates, the fan blades 149 drive the first cooling airflow 60 and the second cooling airflow 70, causing the first cooling airflow 60 and the second cooling airflow 70 to flow towards the outer periphery of the end plate 148 and be discharged from the air outlet 116. In another embodiment, the mounting base 147 has a receiving space 150 for the support 146 to be disposed, and the support 146 has two staggered blocks 151, the shape of the receiving space 150 corresponding to the two blocks 151. In one embodiment, in order to stably connect the support 146 and the airflow generating component 143, the mounting base 147 is provided with at least two limiting arms 152, which are used to limit one of the two blocks 151. Furthermore, the receiving space 150 extends through both ends of the mounting base 147, that is, both ends of the mounting base 147 are open. In order to prevent the support 146 from separating from the airflow generating component 143, the mounting base 147 is provided with a limiting wall 153 on the side of the receiving space 150 away from the end plate 148, the limiting wall 153 and the at least two limiting arms 152 together limit one of the two blocks 151.

[0096] Continuing from the above, in the aforementioned embodiments, the grinding tool 10 does not have a dust collection structure. To further reduce dust dispersion during grinding, the grinding tool 10 can be equipped with an additional dust collection device during grinding. In another embodiment, please refer to... Figures 8 to 10 The grinding tool 10 of this embodiment has a dust collection function. Specifically, during grinding, the grinding tool 10 does not use the first cooling airflow 60 and the second cooling airflow 70 to blow away dust, but instead uses an additional airflow path to suck up dust. Further, the housing 11 of this invention has a mounting opening 119 provided in the head 111, in which the airflow guide 143 is disposed. The size of the mounting opening 119 matches the size of the end plate 148. In other words, the grinding tool 10 of this invention divides the head 111 into upper and lower parts by the end plate 148. The motor 142 is housed in the head 111 on the side of the end plate 148 away from the grinding workpiece 30, allowing the first cooling airflow 60 and the second cooling airflow 70 to flow through it. On the side of the head 111 facing the grinding workpiece 30, the first cooling airflow 60 and the second cooling airflow 70 do not flow, but instead a suction airflow 80 flows through it. To further explain, the grinding tool 10 includes a dust cover 18 located on the head 111 and a dust collection pipe 19 disposed on the dust cover 18. The dust cover 18 is located on the side of the housing 11 facing the grinding part 30 and is assembled to the assembly opening 119. After assembly, the dust cover 18 faces the grinding part 30. The dust collection pipe 19 communicates with the assembly opening 119 through the dust cover 18, thereby forming an airflow path. When the grinding part 30 is grinding, at least one dust particle is generated. The dust particle is blocked by the end plate 148 and moves in the assembly opening 119. The dust cover 18 prevents the dust particle from rapidly spreading to the outside. After the dust collection pipe 19 is activated, it generates a high-pressure suction airflow 80. The suction airflow 80 flows in the airflow path and carries the dust particle, causing the dust particle to flow into the dust collection pipe 19 along the airflow path and reducing the flow into the airflow channel 118.

[0097] On the other hand, please see Figures 6 to 10 In one embodiment, the grinding tool 10 includes an end cap 21 disposed at one open end of the motor housing 117. The end cap 21 is assembled to the side of the motor housing 117 facing the airflow generator 143. After the end cap 21 is assembled, it together with the motor housing 117 shields the motor 142 and enables the motor 142 to work stably.

[0098] On the other hand, please see Figures 6 to 10In one embodiment, the circuit board 141 is disposed on the body 112, and the grinding tool 10 includes a heat sink 22 disposed on the body 112 for dissipating heat from the circuit board 141. The housing 113 forms a positioning groove 120 for providing the heat sink 22, and the air inlet 115 is located in the positioning groove 120 such that the heat sink 22 faces the air inlet 115. Furthermore, the air inlet 115 is composed of a plurality of strip-shaped holes 121. The heat sink 22 includes a substrate 221 disposed on the circuit board 141 and a plurality of heat dissipation fins 222 disposed on the substrate 221. The heat dissipation fins 222 do not interfere with the air inlet 115. Specifically, the heat dissipation fins 222 are arranged at intervals and are not disposed on the air intake path of the strip-shaped holes 121. Therefore, the heat dissipation fins 222 do not affect the air intake of the strip-shaped holes 121.

[0099] In another embodiment, the housing 113 is divided into a lower housing 127 and an upper housing 128. The lower housing 127 is assembled to the motor housing 117, and the upper housing 128 does not contact the motor housing 117. Together with the lower housing 127, the upper housing 128 defines the airflow channel 118. In one embodiment, the lower housing 127 is formed with the air inlet 115. The lower housing 127 provides the first cooling airflow 60 into the housing and allows the first cooling airflow 60 to flow between the upper housing 128 and the lower housing 127. In another embodiment, the motor housing 117 may be formed from one of the housing 113 that is divided into the lower housing 127. Furthermore, the upper housing 128 includes a connecting portion 122 that connects to the lower housing 127 and forms the body 112 together with the lower housing 127, and an extension portion 123 that extends from the connecting portion 122 and forms the head 111 together with the lower housing 127. An operable operating plate 124 is connected to the connecting portion 122. The extension portion 123 covers the motor housing 117 and forms the airflow channel 118 between the extension portion 123 and the motor housing 117. In one embodiment, the extension portion 123 is formed with a connecting hole 125, and the motor housing 117 is formed with a connecting structure 126 that mates with the connecting hole 125. The connecting structure 126 is connected within the connecting hole 125 to help the motor housing 117 be stably disposed in the head 111.

Claims

1. A grinding tool that reduces housing overheating, characterized in that, Include: A housing is divided into a head and a body. The housing is composed of at least two shell parts. The housing has an air inlet formed in the body and an air outlet formed in the head on the side away from the body. The housing has a motor cover in the head. The end of the motor cover facing a grinding part is open. There is a gap between the motor cover and the shell parts to form an airflow channel inside the housing that enters through the air inlet and exits through the air outlet. A drive assembly includes a circuit board disposed within a housing, a motor inserted into a motor housing and connected to the circuit board to drive the grinding workpiece to rotate, and an airflow generator that shields the side of the motor housing facing the grinding workpiece and rotates synchronously with the motor. When the airflow generator rotates, it generates a first cooling airflow within the housing that passes through the airflow channel to dissipate heat from the circuit board and the head of the housing. This first cooling airflow cannot flow into the motor but flows along the surface of the motor housing and the inner wall of the head. A second cooling airflow also exists to dissipate heat from the side of the motor facing the airflow generator. An air guide is disposed inside the housing and located in the airflow channel. The air guide has a receiving end and an air outlet end that is higher than the receiving end.

2. The grinding tool for reducing housing overheating as described in claim 1, characterized in that, The motor housing is cylindrical, and the air guide is formed along the edge of the motor housing with a main guide surface and two auxiliary guide surfaces located on both sides of the main guide surface and having a different airflow direction from the main guide surface.

3. The grinding tool for reducing housing heat generation as described in claim 1 or 2, characterized in that, The air guide extends from both sides into the gap between the side of the motor housing and the inner wall of the head, forming a guide channel. The inlet of the guide channel is higher than the outlet.

4. The grinding tool machine for reducing housing overheating as described in claim 1, characterized in that, The air guide is located at the junction of the body and the head.

5. The grinding tool machine for reducing housing heat generation as described in claim 1 or 2, characterized in that, The motor includes an output shaft and a bearing for the grinding component to be connected to and driven by the output shaft. The airflow generating component includes a mounting base connected to the bearing base, an end plate extending from the mounting base, and a plurality of fan blades disposed on the side of the end plate facing the motor housing.

6. The grinding tool machine for reducing housing overheating as described in claim 5, characterized in that, These fan blades stand on the end plate.

7. The grinding tool machine for reducing housing overheating as described in claim 5, characterized in that, The support comprises two staggered blocks, and the mounting base has a receiving space shaped to accommodate the two blocks.

8. The grinding tool machine for reducing housing overheating as described in claim 7, characterized in that, The mounting base is provided with at least two limiting arms to prevent the bearing from detaching.

9. The grinding tool machine for reducing housing heat generation as described in claim 8, characterized in that, The accommodating space extends through both ends of the mounting base. The mounting base has a limiting wall at the end of the accommodating space away from the fan blades. The limiting wall and the at least two limiting arms together restrict the support.

10. The grinding tool for reducing housing heat generation as described in claim 1 or 2, characterized in that, It also includes an end cap located at the open end of the motor housing.

11. The grinding tool for reducing housing overheating as described in claim 1 or 2, characterized in that, These housing components are divided into a lower housing and an upper housing. The lower housing is assembled with the motor housing, and the upper housing is not in contact with the motor housing and together with the lower housing forms the airflow channel.

12. The grinding tool for reducing housing overheating as described in claim 1 or 2, characterized in that, It also includes a dust cover that is assembled with the housing and located at the head, and a dust collection pipe disposed on the dust cover.

13. The grinding tool for reducing housing heat generation as described in claim 1 or 2, characterized in that, The circuit board is located on the body, and the grinding tool includes a heat sink located on the body and capable of dissipating heat from the circuit board. The housing is formed with a positioning groove for placing the heat sink therein, and the air inlet is formed in the positioning groove.

14. The grinding tool for reducing housing overheating as described in claim 13, characterized in that, The air intake is composed of multiple strip-shaped holes.

Images