Explosion-proof hand-held electric tool for coal mine

Abstract

The present application relates to a kind of coal mine with explosion-proof handheld electric tool, the electric tool includes: shell, motor module, reducer module and battery assembly, installation cavity is equipped in shell, motor module includes motor shell and motor body, motor shell is metal explosion-proof structural member and has first explosion-proof cavity, motor body is located in first explosion-proof cavity, the output shaft of motor body is connected with the transmission of reducer module, battery assembly includes battery box, battery and control panel, battery box is metal explosion-proof structural member, battery box is equipped with second explosion-proof cavity, battery is located in second explosion-proof cavity and is electrically connected with battery module, electric tool further includes speed plate, switch plate, commutating switch and safety barrier, any one of speed plate, switch plate and commutating switch is electrically connected with control panel by safety barrier.The explosion-proof effect of the handheld electric tool of the present application is good, is favorable for guaranteeing the reliability of electric tool work, and weight is lighter.

Description

Technical Field

[0001] This invention relates to the field of power tool technology, and more specifically, to an explosion-proof handheld power tool for coal mines. Background Technology

[0002] Explosion-proof handheld power tools are mainly used in flammable and explosive environments such as petrochemical plants and coal mines to assist workers in bolt assembly, equipment installation, and other operations, ensuring personnel safety. These tools are specifically designed for hazardous environments and feature safety protection systems. While improving the efficiency of underground maintenance and installation work, they effectively prevent the generation of sparks or static electricity, thus avoiding the ignition of flammable gases or dust. In related technologies, explosion-proof handheld power tools often employ an integrated explosion-proof housing, where the motor and fan are installed within the same enclosure. However, this structural arrangement results in greater weight and relatively poor explosion-proof performance. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention provide an explosion-proof handheld power tool for coal mines. This power tool has good explosion-proof performance, which helps to ensure the reliability of the power tool's operation, and it is also lightweight.

[0005] An embodiment of the present invention provides an explosion-proof handheld power tool for coal mines, comprising: a housing, wherein the housing is a non-explosion-proof housing and has an installation cavity therein; a motor module, wherein the motor module includes a motor housing and a motor body, the motor housing being a metal explosion-proof structural component and having a first explosion-proof cavity, the motor body being disposed within the first explosion-proof cavity, and the output shaft of the motor body extending outside the motor housing; a reducer module, wherein the reducer module and the motor module are disposed in the installation cavity along a first direction, and the output shaft is drively connected to the reducer module; a battery assembly, wherein the battery assembly includes a battery box, a battery, and a control board, the battery box being a metal explosion-proof structural component, the battery box being disposed at the lower end of the housing and having a second explosion-proof cavity, the battery and the control board being disposed within the second explosion-proof cavity and electrically connected to the battery module; a speed plate, a switch plate, a reversing switch, and a safety barrier, wherein any one of the speed plate, the switch plate, and the reversing switch is electrically connected to the control board through the safety barrier.

[0006] According to an embodiment of the present invention, the explosion-proof handheld power tool for coal mines has a first explosion-proof cavity inside the motor housing and a second explosion-proof cavity inside the battery box. This allows the motor body and battery to be housed in different explosion-proof cavities, improving the explosion-proof effect of both. Compared to designs where the outer shell is designed as a single explosion-proof structure, this embodiment allows for targeted explosion-proof treatment only on the components requiring explosion protection. This reduces the overall weight of the explosion-proof handheld power tool while ensuring its reliable explosion-proof performance. Furthermore, since any of the speed plate, switch plate, and reversing switch is electrically connected to the control board via a safety barrier, intrinsically safe treatment can be applied to these components to ensure that current and voltage always fluctuate within a safe range. This effectively prevents potential safety hazards and improves the explosion-proof effect of the power tool.

[0007] In some embodiments, the explosion-proof handheld power tool for coal mines further includes a fan, which is disposed between the reducer module and the motor module, and is fixedly connected to the output shaft. The air outlet of the fan is arranged opposite to the motor module.

[0008] In some embodiments, the motor housing includes a housing body, a motor end cap, and a retaining ring. The retaining ring is disposed at the end of the housing body away from the fan. The motor end cap abuts between the housing body and the retaining ring. The motor end cap and the housing body define a first explosion-proof cavity. A first explosion-proof surface is formed between the outer peripheral surface of the motor end cap and the inner peripheral surface of the housing body. A second explosion-proof surface is formed between the outer peripheral surface of the retaining ring and the inner peripheral surface of the housing body.

[0009] In some embodiments, the outer periphery of the motor end cover opposite to the retaining ring is provided with a concave stop, and the shell body is provided with a convex stop, the concave stop abutting against the convex stop, the first explosion-proof surface is an explosion-proof cylindrical surface, and the second explosion-proof surface is an explosion-proof threaded surface.

[0010] In some embodiments, the fan includes a connecting sleeve and a plurality of blades. The connecting sleeve is coaxially fixed on the output shaft. The plurality of blades are arranged circumferentially on the connecting sleeve. Each blade has a first end face and a second end face arranged opposite to each other along its thickness direction. Both the first end face and the second end face are parallel to the axial direction of the output shaft.

[0011] In some embodiments, the fan includes a baffle plate disposed on the side of the connecting sleeve away from the motor module, and a windproof surface is provided at one end of the baffle plate adjacent to the motor module. At least one of the connecting sleeve and the blades is connected to the windproof surface.

[0012] In some embodiments, the wall thickness of the motor housing and the battery box is M, wherein 3mm≤M≤8mm; and / or, the material of the motor housing and the battery box is at least one of gray cast iron, carbon structural steel and stainless steel.

[0013] In some embodiments, the housing is provided with an air inlet and an air outlet, the air inlet being arranged adjacent to the fan, and the air outlet being located on the side of the motor module opposite to the fan.

[0014] In some embodiments, the housing includes a side shell and an end shell, the end shell being disposed at one end of the side shell along the first direction, and the side shell and the end shell forming the mounting cavity, the air outlet being disposed at the connection position of the side shell and the end shell, the air inlet being disposed on the side shell, and the mounting cavity including an air convection area being disposed between the end face of the motor module facing away from the fan and the end shell.

[0015] In some embodiments, the housing further includes a grip portion, the upper end of which is connected to the side shell, the lower end of which is connected to the battery box, the motor module being disposed directly above the grip portion, the reducer module being disposed on one side of the grip portion along the first direction, and the air convection zone being disposed on the other side of the grip portion along the first direction.

[0016] In some embodiments, the explosion-proof handheld power tool for coal mines further includes a first wire threading component, a second wire threading component, and a wire. The first wire threading component is disposed on the motor housing, the second wire threading component is disposed on the battery box, and the wire threading component passes through the cavity of the grip portion. One end of the wire threading component passes through the first wire threading component and is connected to the motor body, and the other end of the wire threading component passes through the second wire threading component and is connected to the battery. Both the first wire threading component and the second wire threading component are provided with a potting compound for fixing the wire threading component.

[0017] In some embodiments, the battery box includes a box body and a cover body, the box body and the cover body being threadedly engaged and defining a second explosion-proof cavity, and the mating position of the box body and the cover body having a third explosion-proof surface.

[0018] In some embodiments, the housing is provided with a mounting hole that communicates with the second explosion-proof cavity. The battery assembly further includes a sealing member and a charging head. The sealing member and at least a portion of the charging head are disposed within the mounting hole. The charging head is closer to the explosion-proof cavity than the sealing member. The sealing member is detachably connected to the mounting hole. The outer wall of at least one of the sealing member and the charging head has a fourth explosion-proof surface with the inner wall of the mounting hole. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0020] Figure 2 This is a cross-sectional view of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0021] Figure 3 This is a partial schematic diagram of the explosion-proof handheld power tool for coal mines with part of its outer shell removed, according to an embodiment of the present invention.

[0022] Figure 4 This is an isometric view of the explosion-proof handheld power tool for coal mines according to an embodiment of the present invention after removing the outer casing and battery assembly.

[0023] Figure 5 This is a cross-sectional view of the explosion-proof handheld power tool for coal mines according to an embodiment of the present invention after removing the outer casing and battery assembly.

[0024] Figure 6 This is a cross-sectional view of the motor module and fan of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0025] Figure 7 This is an isometric view of the battery assembly of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0026] Figure 8 This is a top view of the battery assembly of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0027] Figure 9 yes Figure 8 Cross-sectional view of AA.

[0028] Figure 10 yes Figure 8 Cross-sectional view of BB.

[0029] Figure 11 This is a schematic diagram of the charging circuit of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0030] Figure 12 This is a schematic diagram of the intrinsically safe circuit of an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0031] Figure label:

[0032] 1. Outer shell; 11. Mounting cavity; 111. Air convection zone; 12. Side shell; 121. Air inlet; 13. End shell; 131. Air outlet; 14. Handle;

[0033] 2. Reducer module;

[0034] 3. Motor module; 31. Motor housing; 311. Housing body; 3111. Raised stop; 312. Motor end cover; 3121. Recessed stop; 313. Retaining ring; 314. First explosion-proof surface; 315. Second explosion-proof surface; 32. Motor body; 321. Output shaft; 33. First explosion-proof cavity; 34. Heat sink fins;

[0035] 4. Fan; 41. Connecting sleeve; 42. Blade; 421. First end face; 422. Second end face; 43. Baffle;

[0036] 5. Battery assembly; 51. Battery box; 511. Box body; 5111. Mounting hole; 5112. Ear socket; 5113. Connection hole; 512. Cover; 513. Second explosion-proof chamber; 514. Third explosion-proof surface; 52. Charging head; 53. Sealing component; 54. Fourth explosion-proof surface; 54. Battery; 55. Control board; 56. Blocking diode;

[0037] 61. First threading component; 62. Second threading component; 63. Encapsulating material;

[0038] 7. Fixture module;

[0039] 81. Rotary speed control plate; 82. Switch plate; 83. Reversing switch; 84. Safety barrier. Detailed Implementation

[0040] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0041] The following is a reference appendix. Figures 1 to 12 This invention describes an explosion-proof handheld power tool for coal mines according to an embodiment of the present invention.

[0042] like Figures 1 to 12 As shown, the explosion-proof handheld power tool for coal mines according to an embodiment of the present invention includes: a housing 1, a motor module 3, a reducer module 2, and a battery assembly 5. The housing 1 is a non-explosion-proof housing with an installation cavity 11 inside. The motor module 3 includes a motor housing 31 and a motor body 32. The motor housing 31 is a metal explosion-proof structure and has a first explosion-proof cavity 33. The motor body 32 is located in the first explosion-proof cavity 33, and the output shaft 321 of the motor body 32 extends out of the motor housing 31. The reducer module 2 and the motor module 3 are located in the installation cavity 11 along a first direction, and the output shaft 321 is connected to the reducer module 2 in a transmission manner. The battery assembly 5 includes a battery box 51, a battery 54, and a control board 55. The battery box 51 is a metal explosion-proof structure and is located at the lower end of the housing 1 with a second explosion-proof cavity 513. The battery 54 and the control board 55 are both located in the second explosion-proof cavity 513 and are electrically connected to the battery 54 module.

[0043] According to an embodiment of the present invention, the explosion-proof handheld power tool for coal mines has a first explosion-proof cavity 33 inside the motor housing 31 and a second explosion-proof cavity 513 inside the battery box 51. Therefore, the motor body 32 and the battery 54 can be respectively installed in different explosion-proof cavities to improve the explosion-proof effect of the motor body 32 and the battery 54. Compared to a design where the outer shell 1 is designed as an integral explosion-proof unit, the explosion-proof handheld power tool for coal mines of the present invention allows for targeted explosion-proof treatment only on the components requiring explosion-proof protection. This reduces the overall weight of the explosion-proof handheld power tool for coal mines while ensuring the reliability of its explosion-proof performance.

[0044] Understandably, since the motor module 3 and battery assembly 5 adopt an explosion-proof motor structure, there is no need to design the housing 1 to be explosion-proof. For example, the housing 1 can be made of lightweight plastic or aluminum alloy, thereby reducing the overall weight of the explosion-proof handheld power tool for coal mines.

[0045] Furthermore, such as Figure 12 As shown, the handheld power tool also includes a speed plate 81, a switch plate 82, a reversing switch 83, and a safety barrier 84. Any one of the speed plate 81, switch plate 82, and reversing switch 83 is electrically connected to the control board 55 via the safety barrier 84. Because any one of the speed plate 81, switch plate 82, and reversing switch 83 is electrically connected to the control board 55 via the safety barrier 84, intrinsic safety measures can be implemented for the speed plate 81, switch plate 82, and reversing switch 83, ensuring that the current and voltage always fluctuate within a safe range. This effectively prevents potential safety hazards and improves the explosion-proof performance of the power tool.

[0046] Optionally, such as Figures 3 to 6 As shown, the explosion-proof handheld power tool for coal mines also includes a fan 4, which is located between the reducer module 2 and the motor module 3. The fan 4 is fixedly connected to the output shaft 321, and the air outlet of the fan 4 is arranged opposite to the motor module 3. When the motor module 3 drives the reducer module 2 to rotate, it can simultaneously drive the fan 4 to rotate, thereby cooling the motor module 3. Therefore, the explosion-proof handheld power tool for coal mines of this embodiment can effectively dissipate heat from the motor module 3, which is beneficial to ensuring the reliability of motor operation, and it is also lightweight.

[0047] In related technologies, the fan is usually located at the rear end of the motor module, that is, at the end of the motor module away from the reducer module 2. In the above solution, the air outlet is set at the end of the outer casing near the fan. When the fan rotates, the fan can only dissipate heat from the rear of the motor module, and the heat dissipation effect on the front end of the motor module (that is, the end of the motor module near the reducer) is poor. However, the explosion-proof handheld power tool for coal mines of the present invention, by placing the fan 4 between the reducer module 2 and the motor module 3, and with the air outlet of the fan 4 arranged opposite to the motor module 3, can extend the flow path of the cooling airflow and improve the cooling effect of the motor module 3.

[0048] On the other hand, since the heat generated by the reducer module 2 or the clamp module 7 during operation is not large, there is no need to dissipate it. Therefore, by arranging the air outlet of the fan 4 opposite to the motor module 3, the heat dissipation of the motor module 3 can be concentrated, thereby further improving the heat dissipation effect of the motor module 3.

[0049] In some embodiments, such as Figures 3 to 6 As shown, the motor housing 31 includes a housing body 311, a motor end cover 312, and a retaining ring 313. The retaining ring 313 is located at the end of the housing body 311 facing away from the fan 4. The motor end cover 312 abuts against the housing body 311 and the retaining ring 313. The motor end cover 312 and the housing body 311 define a first explosion-proof cavity 33. A first explosion-proof surface 314 is formed between the outer peripheral surface of the motor end cover 312 and the inner peripheral surface of the housing body 311. A second explosion-proof surface 315 is formed between the outer peripheral surface of the retaining ring 313 and the inner peripheral surface of the housing body 311. It can be understood that both the retaining ring 313 and the motor end cover 312 have explosion-proof mating surfaces with the housing body 311, thereby improving the explosion-proof effect of the motor housing 31. In other words, the retaining ring 313 can both fix the motor end cover 312 to restrict the axial movement of the motor end cover 312 along the housing body 311 and form an explosion-proof mating surface with the housing body 311.

[0050] Specifically, such as Figure 6 As shown, the outer periphery of the motor end cover 312 opposite to the retaining ring 313 has a recessed stop 3121, and the housing body 311 has a convex stop 3111. The recessed stop 3121 abuts against the convex stop 3111. It can be understood that the mating surfaces of the recessed stop 3121 and the convex stop 3111 are generally stepped surfaces, which can increase the length of the explosion-proof mating surface and also provide axial positioning for the motor end cover 312.

[0051] For example, the first explosion-proof surface 314 is an explosion-proof cylindrical surface, and the second explosion-proof surface 315 is an explosion-proof threaded surface. It can be understood that the first explosion-proof surface 314 has a smooth outer circumference, and the motor end cover 312 can be directly installed axially at one end of the housing body 311, abutting against the protruding stop 3111 of the housing body 311. The retaining ring 313 is threadedly engaged with the housing body 311, thereby securing the motor end cover 312. It can be understood that, compared to a threaded connection scheme where the housing body 311 and motor end cover 312 are connected, this application eliminates the need for threaded holes on the housing body 311 and motor end cover 312, thus ensuring the explosion-proof effect of the motor housing 31. Furthermore, compared to a threaded connection scheme where the housing body 311 and motor end cover 312 are connected, this application can reduce the radial dimension of the motor housing 31, which is beneficial for the miniaturization design of explosion-proof handheld power tools for coal mines.

[0052] Optionally, the wall thickness of both the motor housing 31 and the battery box 51 is M, where 3mm ≤ M ≤ 8mm. For example, the materials of the motor housing 31 and the battery box 51 are at least one of gray cast iron, carbon structural steel, and stainless steel. Taking the motor housing 31 of the embodiment of this application as an example, since the motor housing 31 is an explosion-proof metal structural component, when the wall thickness of the housing body 311 and the motor end cover 312 is large, it will result in a large weight of the motor module 3, which is not conducive to holding the power tool. When the wall thickness of the motor housing 31 is small, it will reduce the explosion-proof effect of the motor housing 31. Therefore, the inventors of this application have found through experimental research that when the wall thickness M is between 3mm and 8mm, the explosion-proof effect of the motor housing 31 can be guaranteed, and the weight of the motor housing 31 can be reduced, thus realizing the lightweight design of the explosion-proof handheld power tool for coal mines.

[0053] Optionally, such as Figures 1 to 3 As shown, the outer casing 1 is provided with an air inlet 121 and an air outlet 131. The air inlet 121 is arranged adjacent to the fan 4, and the air outlet 131 is located on the side of the motor module 3 away from the fan 4. Since the fan 4 blows air towards the motor module 3, the air circulation rate between the air inlet 121 and the air outlet 131 can be increased when the fan 4 rotates. That is, the external airflow can quickly pass through the air inlet 121 into the mounting cavity 11, and then the airflow can move towards the motor module 3 and quickly flow out from the air outlet 131, thereby improving the heat dissipation effect of the motor module 3.

[0054] In some embodiments, such as Figures 4 to 6As shown, the fan 4 includes a connecting sleeve 41 and multiple blades 42. The connecting sleeve 41 is coaxially fixed to the output shaft 321. The multiple blades 42 are arranged at intervals along the circumference of the output shaft 321 on the connecting sleeve 41. Each blade 42 has a first end face 421 and a second end face 422 arranged opposite to each other along its thickness direction. Both the first end face 421 and the second end face 422 are parallel to the axial direction of the output shaft 321. It can be understood that since both the first end face 421 and the second end face 422 are parallel to the axial direction of the output shaft 321, when the motor module 3 rotates forward or reverse, the fan 4 can blow air towards the motor module 3, thereby improving the heat dissipation effect of the motor module 3.

[0055] Furthermore, such as Figures 4 to 6 As shown, the fan 4 includes a baffle 43, which is located on the side of the connecting sleeve 41 away from the motor module 3. The end of the baffle 43 adjacent to the motor module 3 has a wind-blocking surface. At least one of the connecting sleeve 41 and the blades 42 is connected to the wind-blocking surface. It can be understood that the baffle 43 can block the airflow flowing towards the reducer module 2, so that the majority of the airflow flows towards the motor module 3.

[0056] For example, the outer periphery of the baffle 43 may be equal in size to the outer periphery formed by the plurality of blades 42, or the outer periphery of the baffle 43 may be slightly larger than the outer periphery formed by the plurality of blades 42.

[0057] In some embodiments, such as Figure 3 As shown, the outer casing 1 includes a side casing 12 and an end casing 13. The end casing 13 is disposed at one end of the side casing 12 along a first direction, and the side casing 12 and the end casing 13 form a mounting cavity 11. An air outlet 131 is disposed at the connection position between the side casing 12 and the end casing 13, and an air inlet 121 is disposed on the side casing 12. It is understood that when an operator uses the power tool equipped with this explosion-proof handheld power tool for coal mines, the operator's face will be facing the end casing 13. Therefore, in the embodiment of the explosion-proof handheld power tool for coal mines of the present invention, the air outlet 131 is disposed at the connection position between the side casing 12 and the end casing 13, which can prevent the airflow from blowing directly on the operator's face, and at the same time, it does not shorten the flow path of the cooling airflow in the mounting cavity 11, resulting in better performance.

[0058] Specifically, such as Figure 2 As shown, there are multiple air outlets 131, which are arranged at intervals along the circumference of the end shell 13. There are also multiple air inlets 121, which are arranged at intervals along the circumference of the side shell 12. This can improve the uniformity of heat dissipation of the motor module 3.

[0059] In one example, the explosion-proof handheld power tool for coal mines also includes a breathable dust cover (not shown), which is disposed inside the mounting cavity 11 and covers the air inlet 121 and the air outlet 131. This prevents external dust from entering the mounting cavity 11, thereby improving the reliability of the power tool's operation.

[0060] In some embodiments, such as Figures 2 to 3 As shown, the mounting cavity 11 includes an air convection zone 111, which is located between the end face of the motor module 3 facing away from the fan 4 and the end shell 13. It can be understood that the end face of the motor module 3 facing away from the fan 4 is spaced apart from the end shell 13 along a first direction. Air cooling the motor module 3 can be buffered by the air convection zone 111 before being discharged through the air outlet 131, thus ensuring the smooth discharge of hot air after cooling the motor.

[0061] Optionally, such as Figures 2 to 3 As shown, the outer casing 1 also includes a grip portion 14, the upper end of which is connected to the side casing 12, the lower end of which is connected to the battery box 51, the motor module 3 is located directly above the grip portion 14, the reducer module 2 is located on one side of the grip portion 14 along the first direction, and the air convection zone 111 is located on the other side of the grip portion 14 along the first direction.

[0062] It is understandable that by providing an air convection zone 111 in the mounting cavity 11, and with the air convection zone 111 located on the other side of the grip 14 along the first direction, the center of gravity of the explosion-proof handheld power tool for coal mines can be located approximately at the position of the grip 14, making it convenient for the user to hold. Furthermore, when the explosion-proof handheld power tool for coal mines is placed vertically (with the lower end face of the battery assembly 5 in contact with the placement surface), the stability of the explosion-proof handheld power tool for coal mines can be improved, avoiding the problem of the explosion-proof handheld power tool for coal mines tipping over during placement.

[0063] For example, such as Figures 2 to 3 As shown, the dimension of the air convection zone 111 along the first direction is A, where 2cm ≤ A ≤ 5cm. For example, the dimension A of the air convection zone 111 along the first direction can be 2cm, 3cm, 4cm, or 5cm. The inventors of this application discovered through experimental research that when the dimension of the air convection zone 111 along the first direction is less than 2cm, the distance between the tail of the motor module 3 and the end shell 13 is relatively short, which is not conducive to heat dissipation of the tail of the motor module 3. When the dimension of the air convection zone 111 along the first direction is greater than 5cm, it will greatly reduce the airflow efficiency within the mounting cavity 11 and increase the weight of the outer shell 1, which is not conducive to the lightweight design of power tools.

[0064] In addition, by setting the air convection zone 111 to the above parameters, it is beneficial to ensure that the center of gravity of the explosion-proof handheld power tool for coal mines is generally located at the grip 14, which is convenient for users.

[0065] Furthermore, such as Figure 3 As shown, the outer periphery of the motor housing 31 is provided with multiple heat dissipation fins 34, which extend along the first direction and are arranged at intervals along the circumference of the motor module 3, thereby further improving the heat dissipation effect of the motor module 3.

[0066] Optionally, such as Figure 7 As shown, the side of the housing 511 opposite to the explosion-proof cavity is provided with a lug 5112, and the lug 5112 has at least two connection holes 5113. For example, there are two lugs 5112, which are arranged at intervals on the housing 511, and each lug 5112 has two connection holes 5113 arranged vertically. It can be understood that the housing 1 of the power tool can be connected to the lug 5112 to integrate the battery assembly 5 onto the power tool, thereby avoiding drilling holes directly on the wall of the battery box 51 and improving the firmness of the installation between the housing 1 and the battery assembly 5.

[0067] In some embodiments, such as Figures 6 to 7 As shown, the explosion-proof handheld power tool for coal mines also includes a first wiring component 61, a second wiring component 62, and a wire (not shown). The first wiring component 61 is located on the motor housing 31, and the second wiring component 62 is located on the battery box 51. The wire passes through the cavity of the grip part 14. One end of the wire passes through the first wiring component 61 and connects to the motor body 32, while the other end passes through the second wiring component 62 and connects to the battery 54. Both the first wiring component 61 and the second wiring component 62 are provided with a potting compound 63 for fixing the wire. It can be understood that by using a potting compound to pass the wire through the battery box 51 and the motor housing 31, the sealing performance of the first explosion-proof cavity 33 and the second explosion-proof cavity 513, as well as the explosion-proof effect of the motor housing 31 and the battery box 51, can be improved.

[0068] For example, the dimension of the encapsulant 63 along the length of the conductor is B, where B ≥ 20 mm, which can further improve the explosion-proof reliability of the battery box 51.

[0069] In some embodiments, such as Figures 9 to 10As shown, the battery box 51 includes a box body 511 and a cover 512. The box body 511 and the cover 512 are threaded together and define a second explosion-proof cavity 513. The mating position of the box body 511 and the cover 512 has a third explosion-proof surface 514. It can be understood that, in the embodiments of the present invention, the cover 512 and the box body 511 of the battery box 51 do not require external fasteners for fixation. The cover 512 and the box body 511 can be fixed by their own threaded mating surfaces, thereby reducing the number of components in the battery assembly 5 and facilitating assembly.

[0070] In the examples of this application, such as Figures 9 to 10 As shown, there are two covers 512, both of which are located at the lower end of the housing 511. One cover 512 corresponds to the battery 54, and the other cover 512 corresponds to the control board 55. It can be understood that the two covers 512 are arranged at intervals at the lower end of the housing 511 and are threaded into the housing 511. This makes it convenient for operators to repair and replace the battery 54 and the control board 55 of the battery assembly 5.

[0071] Optionally, such as Figures 9 to 10 As shown, the housing 511 is provided with a mounting hole 5111, which is connected to the second explosion-proof cavity 513. The battery assembly 5 also includes a sealing member 53 and a charging head 52. The sealing member 53 and at least part of the charging head 52 are both located in the mounting hole 5111. The charging head 52 is closer to the explosion-proof cavity than the sealing member 53. The sealing member 53 is detachably connected to the mounting hole 5111. The outer wall of at least one of the sealing member 53 and the charging head 52 has a fourth explosion-proof surface 54 with the inner wall of the mounting hole 5111.

[0072] Understandably, the charging head 52 assembly also has an explosion-proof mating surface with the mounting hole 5111 to improve the explosion-proof effect of the battery assembly 5.

[0073] Furthermore, since the sealing element 53 is detachably connected, when the operator needs to charge the battery assembly 5, the sealing element 53 can be removed from the mounting hole 5111 so that the charging plug can be inserted into the charging head 52 for charging. After charging is complete, the sealing element 53 can be installed in the charging head 52, thereby preventing dust and other impurities from entering the charging head 52 and also providing a certain degree of explosion protection.

[0074] For example, the sealing component 53 is a screw plug, which is threaded into the inner wall of the mounting hole 5111 and has a fourth explosion-proof surface 54. This can prevent dust and other impurities from entering the charging head 52 and also provide a certain explosion-proof effect.

[0075] For example, the sealing element 53 is a rubber plug, and the outer wall of the charging head 52 and the inner wall of the mounting hole 5111 have a fourth explosion-proof surface 54. It can be understood that since the charging head 52 and the inner wall of the mounting hole 5111 have explosion-proof mating surfaces, the position of the sealing element 53 does not need to be explosion-proofed. Therefore, the sealing element 53 can be made of rubber plug, so that the operator can install and remove the sealing element 53 by hand, which is more practical.

[0076] For example, such as Figure 11 As shown, the battery assembly 5 also includes two series-connected blocking diodes 56. The positive terminal of the charging head 52 is electrically connected to the positive terminal of the blocking diode 56, the negative terminal of the blocking diode 56 is electrically connected to the positive terminal of the battery 54, and the negative terminal of the battery 54 is electrically connected to the negative terminal of the charging head 52. Because the blocking diode 56 is provided in the charging circuit between the charging head 52 and the battery 54, the charging circuit can only be forward-conducting. That is, the charging circuit between the charging head 52 and the battery 54 constitutes an intrinsically safe circuit, enabling the battery 54 charging structure to operate in flammable and explosive construction environments. Therefore, the battery 54 charging structure of this embodiment combines explosion-proof and intrinsically safe features, can adapt to flammable and explosive construction environments, is less likely to cause safety accidents, and has good reliability.

[0077] In the example of this application, the explosion-proof handheld power tool for coal mines can be one of a hand drill, an impact drill, or a hand saw. A clamping module 7 is provided at the end of the reducer module 2 facing away from the motor module 3. The clamping module 7 is used to clamp tools such as screwdriver bits, drill bits, and saw blades. The reducer module 2 and the clamping module 7 can be a single integrated structure and are snapped into the housing 1.

[0078] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0079] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0080] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0081] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0082] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0083] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A handheld power tool for coal mines, characterized in that, include: The housing is a non-explosion-proof housing, and the housing has an internal mounting cavity; The motor module includes a motor housing and a motor body. The motor housing is a metal explosion-proof structure and has a first explosion-proof cavity. The motor body is disposed in the first explosion-proof cavity, and the output shaft of the motor body extends out of the motor housing. A speed reducer module and a motor module are disposed in the mounting cavity along a first direction, and the output shaft is connected to the speed reducer module in a transmission manner. A battery assembly, comprising a battery box, a battery, and a control board, wherein the battery box is a metal explosion-proof structure, the battery box is located at the lower end of the outer shell and has a second explosion-proof cavity, and the battery and the control board are located in the second explosion-proof cavity and are electrically connected to the battery; The control board includes a speed plate, a switch plate, a reversing switch, and a safety barrier, wherein any one of the speed plate, the switch plate, and the reversing switch is electrically connected to the control board through the safety barrier. A fan is disposed between the reducer module and the motor module, and the fan is fixedly connected to the output shaft. The air outlet of the fan is arranged opposite to the motor module. The motor housing includes a housing body, a motor end cover, and a retaining ring. The retaining ring is located at the end of the housing body away from the fan. The motor end cover abuts between the housing body and the retaining ring. The motor end cover and the housing body define the first explosion-proof cavity. A first explosion-proof surface is formed between the outer peripheral surface of the motor end cover and the inner peripheral surface of the housing body. A second explosion-proof surface is formed between the outer peripheral surface of the retaining ring and the inner peripheral surface of the housing body.

2. The explosion-proof handheld power tool for coal mines according to claim 1, characterized in that, The outer periphery of the motor end cover opposite to the retaining ring is provided with a concave stop, and the shell body is provided with a convex stop. The concave stop and the convex stop abut against each other. The first explosion-proof surface is an explosion-proof cylindrical surface, and the second explosion-proof surface is an explosion-proof threaded surface.

3. The explosion-proof handheld power tool for coal mines according to claim 1, characterized in that, The fan includes a connecting sleeve and multiple blades. The connecting sleeve is coaxially fixed on the output shaft. The multiple blades are arranged circumferentially on the connecting sleeve. Each blade has a first end face and a second end face arranged opposite to each other along its thickness direction. Both the first end face and the second end face are parallel to the axial direction of the output shaft.

4. The explosion-proof handheld power tool for coal mines according to claim 3, characterized in that, The fan includes a baffle plate located on the side of the connecting sleeve away from the motor module. The end of the baffle plate adjacent to the motor module has a windproof surface, and at least one of the connecting sleeve and the blades is connected to the windproof surface.

5. The explosion-proof handheld power tool for coal mines according to claim 1, characterized in that, The wall thickness of the motor housing and the battery box is M, where 3mm≤M≤8mm; And / or, the motor housing and the battery box are made of at least one of gray cast iron, carbon structural steel and stainless steel.

6. The explosion-proof handheld power tool for coal mines according to claim 1, characterized in that, The housing is provided with an air inlet and an air outlet. The air inlet is arranged adjacent to the fan, and the air outlet is located on the side of the motor module away from the fan.

7. The explosion-proof handheld power tool for coal mines according to claim 6, characterized in that, The outer casing includes a side shell and an end shell. The end shell is disposed at one end of the side shell along the first direction, and the side shell and the end shell form the mounting cavity. The air outlet is disposed at the connection position of the side shell and the end shell, and the air inlet is disposed on the side shell. The mounting cavity includes an air convection area, which is disposed between the end face of the motor module facing away from the fan and the end shell.

8. The explosion-proof handheld power tool for coal mines according to claim 7, characterized in that, The outer casing also includes a grip portion, the upper end of which is connected to the side shell, the lower end of which is connected to the battery box, the motor module is located directly above the grip portion, the reducer module is located on one side of the grip portion along the first direction, and the air convection zone is located on the other side of the grip portion along the first direction.

9. The explosion-proof handheld power tool for coal mines according to claim 8, characterized in that, The explosion-proof handheld power tool for coal mines also includes a first wire threading component, a second wire threading component, and a wire. The first wire threading component is disposed on the motor housing, the second wire threading component is disposed on the battery box, and the wire threading component passes through the cavity of the grip part. One end of the wire threading component passes through the first wire threading component and is connected to the motor body, and the other end of the wire threading component passes through the second wire threading component and is connected to the battery. Both the first wire threading component and the second wire threading component are provided with a potting compound for fixing the wire threading component.

10. The explosion-proof handheld power tool for coal mines according to claim 1, characterized in that, The battery box includes a box body and a cover body. The box body and the cover body are threaded together and define the second explosion-proof cavity. The mating position of the box body and the cover body has a third explosion-proof surface.

11. The explosion-proof handheld power tool for coal mines according to claim 10, characterized in that, The housing is provided with a mounting hole, which communicates with the second explosion-proof cavity. The battery assembly also includes a sealing member and a charging head. The sealing member and at least part of the charging head are disposed in the mounting hole. The charging head is closer to the second explosion-proof cavity than the sealing member. The sealing member is detachably connected to the mounting hole. The outer wall of at least one of the sealing member and the charging head has a fourth explosion-proof surface with the inner wall of the mounting hole.

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