Explosion-proof motor

Abstract

The utility model belongs to motor technical field, especially relate to a kind of explosion-proof motor of optimized internal electrical connection and wiring structure.The internal wiring device (3) of explosion-proof motor is provided, the first group cable of the incoming line interface row end of this wiring device (3) is connected with motor (2), the power cable and signal cable connected with outgoing line interface row end are stretched out outside shell assembly (1), the internal connection of cable is realized neat and centralized outside leading, to simplify assembly process, facilitate later maintenance, and optimize the leading mode of cable, reduce the sealing point required for explosion-proof on shell assembly (1), to improve the overall reliability and explosion-proof performance of explosion-proof motor.

Description

Technical Field

[0001] This utility model belongs to the field of motor technology, and specifically relates to an explosion-proof motor with optimized internal electrical connections and wiring structure. Background Technology

[0002] Explosion-proof motors are special motors used in flammable and explosive environments (such as petroleum, chemical, coal mine, natural gas and other places). The core requirement is that the motor cannot generate electric sparks during operation, and its casing must be able to withstand the internal explosion pressure and prevent the explosion from spreading to the external environment.

[0003] To achieve complex motion control and safety protection, modern explosion-proof motors (especially explosion-proof servo motors) typically include not only the motor body but also functional components such as brakes and angle sensors (e.g., encoders, rotary transformers). These components require corresponding cables to transmit power or signals.

[0004] In existing technologies, the power cables from the motor body (especially the stator coils), the control cables from the brake, and the signal cables from the angle sensor inside the explosion-proof motor are typically connected in a dispersed manner within the motor housing. Firstly, the internal wiring is messy and complex, increasing assembly difficulty and time, and making subsequent maintenance or component replacement (such as replacing the brake or sensor) extremely inconvenient. Secondly, multiple sets of cables (such as power cables and signal cables) need to exit the explosion-proof housing separately, increasing the number of explosion-proof sealing points, thereby increasing manufacturing costs and the risk of seal failure. Utility Model Content

[0005] In view of this, this utility model proposes an explosion-proof motor, which aims to optimize the internal electrical connections and wiring structure of the explosion-proof motor.

[0006] In the explosion-proof motor provided by this utility model, the explosion-proof motor includes a housing assembly, a motor and a wiring device disposed in the housing assembly. The motor is connected to a drive shaft extending along its axis, and a first set of cables with exposed stator coils at the bottom end of the motor; the wiring device is provided with an inlet interface row and an outlet interface row, the inlet interface row being connected to the first set of cables, and the power cable and signal cable connected to the outlet interface row extending outside the housing assembly.

[0007] In a preferred embodiment of the explosion-proof motor provided by this utility model, the housing assembly includes a main housing and a first intermediate seat. The first intermediate seat is connected to the bottom end of the main housing. The motor is located in a first accommodating space of the main housing. The first intermediate seat forms a second accommodating space on the side opposite to the motor. The explosion-proof motor also includes a brake. The outer shell of the brake is connected to the second accommodating space, and the central hole of its brake wheel allows the drive shaft to pass through and connect to the drive shaft. The second set of cables exposed by the brake is connected to the inlet interface terminal.

[0008] In a preferred embodiment of the explosion-proof motor provided by this utility model, the housing assembly further includes a second intermediate seat and a base. The second intermediate seat is connected to the bottom end of the first intermediate seat, and the base is connected to the bottom end of the second intermediate seat. A third accommodating space is formed between the base and the second intermediate seat. The explosion-proof motor further includes an angle sensor. The housing of the angle sensor is connected to the inner wall of the second intermediate seat, and the central hole of its rotating part is for the transmission shaft to pass through. The third set of cables of the angle sensor is connected to the inlet interface terminal.

[0009] In a preferred embodiment of the explosion-proof motor provided by this utility model, both the wiring device and the angle sensor are disposed in the third accommodating space.

[0010] In a preferred embodiment of the explosion-proof motor provided by this utility model, the explosion-proof motor further includes multiple metal connecting columns, which extend perpendicularly to the bottom surface of the second middle seat towards the base, and support and connect the wiring device at a position higher than the angle sensor.

[0011] In a preferred embodiment of the explosion-proof motor provided by this utility model, the explosion-proof motor further includes an internal grounding terminal, which is disposed on the metal base plate of the wiring device and is also connected to the inlet or outlet interface of the wiring device via a fourth cable.

[0012] In a preferred embodiment of the explosion-proof motor provided by this utility model, cable through holes are provided on the bottom surfaces of both the first and second intermediate seats for the first or second set of cables to pass through.

[0013] In a preferred embodiment of the explosion-proof motor provided by this utility model, the explosion-proof motor further includes two dynamic balancing rings, which are disposed on the transmission shaft and located inside the two shaft ends of the motor.

[0014] In a preferred embodiment of the explosion-proof motor provided by this utility model, the explosion-proof motor further includes a top cover, a first bearing, and a second bearing. The top cover is connected to the top of the main housing. The first bearing is installed on the inner side of the top cover and supports the drive shaft. The second bearing is installed on the top side of the first intermediate seat and supports the drive shaft.

[0015] In a preferred embodiment of the explosion-proof motor provided by this utility model, the explosion-proof motor further includes two glands, which are fixed to the outer wall of the second intermediate seat. One gland is used for the power cable to pass through, and the other gland is used for the signal cable to pass through.

[0016] The explosion-proof motor provided by this utility model has a wiring device inside. The inlet port of the wiring device is connected to the first set of cables of the motor, and the power cable and signal cable connected to the outlet port extend out of the housing assembly. This realizes the standardization of the internal connection of the cables and the centralization of the external lead-out, which simplifies the assembly process, facilitates later maintenance, optimizes the cable lead-out method, reduces the number of sealing points required for explosion protection on the housing assembly, and thus improves the overall reliability and explosion protection performance of the explosion-proof motor. Attached Figure Description

[0017] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can more clearly understand the above and other features and advantages of the present invention, in which:

[0018] Figure 1 This is a schematic diagram of the external structure of a preferred embodiment of the explosion-proof motor in this example.

[0019] Figure 2 This is an exploded view of the explosion-proof motor in this embodiment.

[0020] Figure 3 This is a cross-sectional view of the explosion-proof motor in this embodiment.

[0021] Figure 4 This is a schematic diagram of the installation structure of the dynamic balancing ring of the explosion-proof motor in this embodiment.

[0022] Figure 5 This is a schematic diagram of the installation structure of the wiring device for the explosion-proof motor in this embodiment.

[0023] The reference numerals in the attached figures are as follows:

[0024] 1-Housing assembly; 11-Main housing; 12-First intermediate base; 13-Second intermediate base; 14-Base; 15-Top cover; 101-Cable pass-through hole;

[0025] 2-Motor; 21-Drive shaft;

[0026] 3-Wiring device; 31-Metal base plate; 32-Metal connecting post; 33-Internal grounding terminal;

[0027] 4-Brake;

[0028] 5-Angle sensor device;

[0029] 6-Dynamic balancing ring;

[0030] 71 - First bearing; 72 - Second bearing;

[0031] 8-Grand Head. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0033] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "connection" and "configuration" 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 or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] Furthermore, it should be understood in the description of this application that the terms “center,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0035] This embodiment provides an explosion-proof motor, specifically, an explosion-proof servo motor or a special explosion-proof motor with high integration requirements.

[0036] Reference Figures 1 to 5 The explosion-proof motor in this embodiment, from an overall structural perspective, includes a housing assembly 1 and a motor 2, a brake 4, an angle sensor 5, and a wiring device 3 disposed within the housing assembly 1. It should be noted that the wiring device 3 can be a single unit or a functional entity comprised of multiple connectors connected together.

[0037] The housing assembly 1 is the foundation for achieving the explosion-proof function, forming a sealed explosion-proof space that houses all internal components. In this embodiment, the housing assembly 1 can adopt a split-type stacked structure to facilitate assembly and division of functional areas.

[0038] Specifically, the housing assembly 1 may include a top cover 15, a main housing 11, a first middle seat 12, a second middle seat 13, and a base 14.

[0039] The top cover 15 is connected to the top of the main housing 11; the first intermediate seat 12 is connected to the bottom of the main housing 11; the second intermediate seat 13 is connected to the bottom of the first intermediate seat 12; and the base 14 is connected to the bottom of the second intermediate seat 13. These components are all connected by explosion-proof stops (such as flat stops or cylindrical stops) and fastened with high-strength bolts. O-rings or oil-resistant and high-temperature-resistant sealants are also provided to ensure the connection strength and sealing performance of the entire housing assembly 1, meeting the explosion-proof ("d") or increased safety ("e") requirements of standards such as GB 3836.

[0040] Inside the housing assembly 1, the aforementioned stacked structure naturally forms multiple accommodating spaces:

[0041] The first accommodating space is enclosed by the main housing 11. The main body of the motor 2 (including the stator and rotor) is located in this first accommodating space. The motor 2 is a power source, for example, it can be a permanent magnet synchronous servo motor.

[0042] The second receiving space is formed by the first middle seat 12 on the side opposite to the motor 2 (i.e., below). The brake 4 (i.e., the brake unit) is installed in this space.

[0043] The third accommodating space is formed between the second middle seat 13 and the base 14. The angle sensor 5 and the wiring device 3 are both located in this space.

[0044] A drive shaft 21 is positioned along the axis of the motor 2, passing through the aforementioned components and spaces. The rotor of the motor 2 is fixed to the drive shaft 21. The stator of the motor 2 is fixed to the inner wall of the main housing 11. A first set of cables with stator coils is led out from the bottom end of the motor 2 (near the first intermediate seat 12). This set of cables may include three-phase power lines (U, V, W) and possibly temperature sensor lines (such as PTC or KTY84).

[0045] To ensure stable rotation of the drive shaft 21, at least two bearings are provided. Specifically, a first bearing 71 is mounted on the inner side of the top cover 15 (e.g., pressed into the bearing housing of the top cover 15) to support the upper end of the drive shaft 21; a second bearing 72 is mounted on the top side of the first intermediate seat 12 (e.g., pressed into the bearing housing of the first intermediate seat 12) to support the lower end of the drive shaft 21. These two bearings (e.g., deep groove ball bearings or angular contact bearings) together provide radial and axial support for the drive shaft 21.

[0046] The brake 4 is installed in the second receiving space, and its housing (e.g., brake coil housing) can be fixed to the inner wall or bottom surface of the first intermediate seat 12. The central hole of its brake wheel (brake disc) allows the drive shaft 21 to pass through, and it rotates synchronously with the drive shaft 21 through key connection, spline connection or interference fit.

[0047] The brake 4 is preferably a power-off brake. Its exposed second set of cables (usually two power lines) is used to control the brake 4 coil. When the second set of cables is energized, the electromagnet is attracted, the brake wheel is released, and the drive shaft 21 can rotate freely; when the power is off, the spring force causes the brake wheel to be braked, thereby locking the drive shaft 21, which plays a role in safety braking or position holding.

[0048] Angle sensor 5 is installed in the third receiving space, and its housing (stator part) is fixed to the inner wall of the second intermediate seat 13. The central hole of its rotating part (rotor part) is also for the drive shaft 21 to pass through, and is fixedly connected to the drive shaft 21.

[0049] The angle sensor 5 can be a high-precision absolute encoder (such as an EnDat or BiSS interface), an incremental encoder, or a more reliable rotary transformer for harsh environments. This component is used to detect the precise rotation angle and speed of the drive shaft 21 in real time and output this information through its third set of cables (typically including a power line and multiple signal lines) to achieve closed-loop servo control of the motor 2.

[0050] Reference Figure 5 To improve the smoothness of motor 2 during high-speed operation, two dynamic balancing rings 6 are also provided on the transmission shaft 21 in this embodiment. These two rings are preferably located at the two shaft ends of the motor 2 rotor, i.e., inside the two shaft ends of the motor 2 stator. By removing weight (e.g., drilling holes) or adding counterweights to the dynamic balancing rings 6, high-precision dynamic balancing correction of the rotor assembly can be achieved. This significantly reduces vibration and noise during motor 2 operation, and improves bearing life and encoder measurement accuracy.

[0051] Combination Figure 3 and Figure 5The core improvement of this embodiment lies in the wiring device 3 and its connection method with the cables of various components. The wiring device 3 is located inside the housing assembly 1 (specifically in the third accommodating space). This wiring device 3 can be a custom PCB circuit board or an integrated terminal block. It is designed to have two sets of interfaces: an inlet interface block and an outlet interface block. These "interface blocks" can be pins, terminals, pads, or dedicated connectors on the PCB.

[0052] To allow the upper cables to reach the third receiving space located at the bottom, cable perforations 101 are provided on the bottom surfaces of both the first intermediate seat 12 and the second intermediate seat 13. These cable perforations 101 should be designed to ensure that they do not compromise the strength and sealing of the explosion-proof housing, for example, by sealing the perforations or ensuring that the perforations are located on the internal non-explosion-proof interface.

[0053] The first set of cables (from motor 2) passes through the perforations on the first middle seat 12 and the second middle seat 13 and enters the third receiving space.

[0054] The second set of cables (from the brake 4) passes through the perforation on the second middle seat 13 and enters the third receiving space.

[0055] The third set of cables (from angle sensor 5) has the shortest routing distance because the sensor itself is located in the third housing space.

[0056] The first, second, and third groups of cables mentioned above are all connected to the inlet port of the wiring device 3. For example, on a PCB board, they can be soldered or connected to the corresponding inlet ports via connectors.

[0057] The output interface of the wiring device 3 is used to connect external cables. In this embodiment, the external cables are divided into power cables and signal cables. The power cables include lines requiring high current (such as the U / V / W phase lines of motor 2 and the power line of brake 4). The signal cables include low-voltage signal lines (such as the signal line of angle sensor 5 and the signal line of temperature sensor of motor 2). These two cables (power cables and signal cables) exit from the output interface of the wiring device 3 and pass through the outside of the housing assembly 1.

[0058] In this embodiment, an "electrical hub" (i.e., wiring device 3) is installed inside the explosion-proof housing. The cables of all internal functional components (motor 2, brake 4, sensors) are no longer scattered and independently protruding from the housing, or haphazardly soldered inside the housing, as in existing technologies. This has the following advantages:

[0059] (1) Simple assembly: All internal cables are connected to a standardized wiring device 3, with clear wiring, making the assembly and debugging process (especially the wiring of motor 2, brake 4, and sensor) extremely simple and efficient.

[0060] (2) Easy maintenance: When a component (such as the brake 4) needs to be replaced, simply open the base 14 in the third accommodating space and disconnect the cable (such as the second set of cables) of the component from the wiring device 3 to replace it. There is no need to deal with complicated internal soldering points.

[0061] (3) Reduced explosion-proof outlets: All electrical connections are ultimately led out through only two cables, power cable and signal cable, which reduces the number of explosion-proof outlets (glan 8) required on the housing, reducing costs and the risk of seal failure.

[0062] The following details the specific layout and grounding method within the third containment space.

[0063] As mentioned above, combined with Figure 5 Both the wiring device 3 and the angle sensor 5 are housed in the third receiving space. To accommodate these two components within the limited axial space, this embodiment employs a three-dimensional stacked layout. The angle sensor 5 is conventionally mounted on the inner wall of the second intermediate base 13 (i.e., near the drive shaft 21). Multiple metal connecting posts 32 (e.g., 3-4 brass or stainless steel support posts) extend perpendicularly to the bottom surface of the second intermediate base 13 (or are fixed to the housing of the angle sensor 5) towards the base 14. The wiring device 3 is fixed to the ends of these metal connecting posts 32 with screws, thus being supported and connected at a position higher than the angle sensor 5 (i.e., wiring device 3 below, sensor above). From the perspective of wiring and installation convenience, it is more reasonable for the sensor to be closer to the motor 2 and the wiring device 3 closer to the base 14. This three-dimensional stacking method greatly improves space utilization, allowing the motor 2 to integrate wiring functions with a constant or minimal increase in overall length, resulting in a very compact structure.

[0064] The safe grounding of explosion-proof motors is of paramount importance. This embodiment provides an integrated internal grounding method.

[0065] Specific structure: The wiring device 3 itself has a metal base plate 31 (for example, if the wiring device 3 is a PCB, it may be a metal plate for reinforcement and shielding; if it is a terminal block, it may be its metal base). An internal grounding terminal 33 (e.g., a grounding stud or a dedicated PE terminal) is provided on the metal base plate 31. The internal grounding terminal 33 is connected to the grounding (PE) terminal on the inlet or outlet interface of the wiring device 3 via a fourth cable (grounding wire).

[0066] The grounding wires of components such as motor 2 and brake 4 (if present) can be connected to this internal grounding terminal 33, or to the PE point of the incoming line interface. Finally, all internal groundings converge to the wiring device 3, and then are safely connected to the external ground through the PE yellow-green ground wire in the external power cable.

[0067] The explosion-proof motor in this embodiment provides a clear, reliable, and centralized internal grounding path, ensuring equipotential bonding and safe grounding of all electrical components, in compliance with explosion-proof safety standards.

[0068] Finally, the method of external cable exiting the housing is described. Two cable glands (also called cable entry devices) are provided. These two cable glands are standard components that meet explosion-proof requirements. They are threaded onto the outer wall of the second intermediate seat 13 (because the second intermediate seat 13 is close to the third receiving space, the cable routing is shortest). One cable gland is used for the power cable to exit externally, achieving an explosion-proof seal. The other cable gland is used for the signal cable to exit externally, achieving an explosion-proof seal. This arrangement has the following advantages:

[0069] (1) Explosion-proof seal: Gland 8 is the key to enabling the cable to pass through the explosion-proof housing and remain sealed.

[0070] (2) Electromagnetic Compatibility (EMC): Leading out high-voltage power cables and low-voltage signal cables through two separate gland 8 connectors and maintaining a physical distance is the standard practice for achieving good electromagnetic compatibility. This effectively prevents electromagnetic interference to sensitive signals such as encoders when the motor switches between high currents, ensuring the stability of the control system.

[0071] Brief description of equipment operation: The external controller supplies power to the explosion-proof motor via signal and power cables. The cables enter the third receiving space through gland 8. The cables connect to the "outgoing interface terminal" of the wiring device 3. The wiring device 3 distributes commands and power through the "incoming interface terminal". Power is supplied to the stator coil of motor 2 via the first set of cables, causing it to generate a rotating magnetic field. Brake power is supplied to brake 4 via the second set of cables, energizing its coil and releasing it. Sensor power is supplied to angle sensor 5 via the third set of cables. All cables are laid through cable through holes 101.

[0072] The rotor of motor 2, supported by the first bearing 71 and the second bearing 72, drives the transmission shaft 21 to rotate. The dynamic balancing ring 6 ensures its smooth rotation.

[0073] The angle sensor 5 detects the position of the drive shaft 21 in real time, and feeds the signal back to the external controller through the third set of cables → wiring device 3 → signal cable → gland 8, forming a closed-loop control.

[0074] All internal groundings are converged and safely led out through internal grounding terminal 33.

[0075] The explosion-proof motor in this embodiment innovatively incorporates an integrated wiring device 3, which unifies the cables of the motor 2, brake 4, and sensor, and then leads them out through a separate power and signal gland 8. Simultaneously, the metal connecting post 32 enables three-dimensional stacking of components, and a reliable internal grounding terminal 33 is provided. This design has the following outstanding advantages:

[0076] (1) Compact structure: high space utilization and high integration.

[0077] (2) Highly efficient assembly: The internal wiring is clear and standardized, which greatly simplifies the assembly and production process.

[0078] (3) Easy maintenance: Parts replacement (especially brake 4 and sensor) becomes easy, without the need to deal with complicated internal wiring.

[0079] (4) High reliability: The number of explosion-proof sealing points has been reduced, power and signal are separated (strong anti-interference), grounding is reliable, and the overall operating stability and explosion-proof safety of motor 2 have been improved.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention, such as different forms of wiring devices (PCBs or terminal blocks), different types of angle sensor devices (encoders or resolvers), or specific disassembly methods of housing components, should all be covered within the scope of protection of the present invention.

[0081] It should be understood that although this specification is described according to various embodiments, not every embodiment or implementation method contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0082] The above descriptions are merely illustrative embodiments of this application and are not intended to limit the scope of the embodiments of this application. Any equivalent changes, modifications, and combinations made by those skilled in the art without departing from the concept and principles of the embodiments of this application should fall within the protection scope of the embodiments of this application.

Claims

1. An explosion-proof motor, characterized in that, Includes a housing assembly (1), and a component disposed within the housing assembly (1): The motor (2) is connected to a drive shaft (21) extending along its axis, and the bottom end of the motor (2) has a first set of cables with exposed stator coils. The wiring device (3) is provided with an inlet interface and an outlet interface. The inlet interface is connected to the first set of cables, and the power cable and signal cable connected to the outlet interface extend out of the housing assembly (1).

2. The explosion-proof motor according to claim 1, characterized in that, The housing assembly (1) includes a main housing (11) and a first middle seat (12). The first middle seat (12) is connected to the bottom end of the main housing (11). The motor (2) is located in a first receiving space of the main housing (11). The first middle seat (12) has a second receiving space on the side facing away from the motor (2). The explosion-proof motor also includes: The brake (4) has its housing connected to the second receiving space, and its brake wheel has a central hole through which the drive shaft (21) passes and is connected to the drive shaft (21). The second set of cables exposed by the brake (4) is connected to the inlet interface terminal.

3. The explosion-proof motor according to claim 2, characterized in that, The housing assembly (1) further includes a second middle seat (13) and a base (14), the second middle seat (13) being connected to the bottom end of the first middle seat (12), the base (14) being connected to the bottom end of the second middle seat (13), and a third receiving space being formed between the base (14) and the second middle seat (13); The explosion-proof motor also includes: An angle sensor (5) has its housing connected to the inner wall of the second middle seat (13), and the central hole of its rotating part is for the transmission shaft (21) to pass through, and the third set of cables of the angle sensor (5) is connected to the inlet interface terminal.

4. The explosion-proof motor according to claim 3, characterized in that, Both the wiring device (3) and the angle sensor (5) are located in the third accommodating space.

5. The explosion-proof motor according to claim 4, characterized in that, Also includes: Multiple metal connecting columns (32) extend perpendicularly to the bottom surface of the second middle seat (13) toward the base (14) and support the wiring device (3) at a position higher than the angle sensor (5).

6. The explosion-proof motor according to claim 5, characterized in that, Also includes: An internal grounding terminal (33) is disposed on the metal base plate (31) of the wiring device (3) and is also connected to the inlet or outlet interface of the wiring device (3) via a fourth cable.

7. The explosion-proof motor according to claim 3, characterized in that, Both the first middle seat (12) and the second middle seat (13) have cable through holes (101) on their bottom surfaces for the first group of cables or the second group of cables to pass through.

8. The explosion-proof motor according to claim 3, characterized in that, Also includes: Two dynamic balancing rings (6) are mounted on the transmission shaft (21) and located inside the two shaft ends of the motor (2).

9. The explosion-proof motor according to claim 2, characterized in that, Also includes: Top cover (15), which is attached to the top of the main housing (11); A first bearing (71) is installed on the inside of the top cover (15) and supports the drive shaft (21); The second bearing (72) is mounted on the top side of the first intermediate seat (12) and supports the drive shaft (21).

10. The explosion-proof motor according to claim 3, characterized in that, Also includes: Two glands (8) are fixed to the outer wall of the second middle seat (13), one gland (8) is used for the power cable to pass out, and the other gland (8) is used for the signal cable to pass out.

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