CN118728998A - Flameproof two-position five-way solenoid reversing valve - Google Patents

Abstract

The present invention relates to the field of reversing valves, and specifically to an explosion-proof two-position five-way electromagnetic reversing valve, comprising a valve body and a valve stem, the valve body being provided with an air inlet, a first air outlet, a second air outlet, a first exhaust port and a second exhaust port, the valve body also being provided with an air flow passage which can be connected with the air inlet and extend to two ends of the valve body, and an air guide structure which is respectively arranged at two ends of the valve body and can cooperate with the corresponding air flow passage to push the valve stem to move, the valve stem being provided with a flat ring, the valve body being provided with a node corresponding to the flat ring, a sealing ring being provided at the node, and coaxial sealing assemblies being provided at both ends of the valve stem, the present invention sealingly seals the valve stem and the valve cavity together in a sliding state through the coaxial sealing assembly, thereby ensuring the sealed transmission of gas in a specific channel inside the valve body and avoiding leakage, and enabling the flat ring cooperating with the sealing ring to be accurately docked together, thereby avoiding sealing failure caused by movement deviation.

Description

Flameproof two-position five-way solenoid reversing valve

Technical Field

The invention relates to the field of reversing valves, in particular to a flameproof two-position five-way electromagnetic reversing valve.

Background Art

Valve products are widely used in fluid control in various technical fields. Two-position five-way solenoid valve is one of them. A two-position five-way solenoid valve refers to a valve body with five air ports, namely one air inlet, two air outlets and two exhaust ports, and the valve stem can move back and forth in two positions. When working, the axial movement of the valve stem is used to switch the air path. Traditional solenoid valves set a number of flat rings on the outside of the valve stem. When the valve stem moves axially, the flat rings are used to seal or disengage with the inner wall of the valve body to switch the air path. Since the flat rings are usually made of rubber material, not only will the friction resistance be increased, resulting in lower sensitivity, but also when the valve stem moves frequently, the flat rings are prone to wear, which reduces the air tightness and causes air leakage in the valve body, affecting the working performance and service life of the valve.

The currently disclosed Chinese patent CN106895176B two-position five-way ceramic slide plate type solenoid valve includes a valve body, a valve stem movably arranged in the valve cavity of the valve body, and a left end cover and a right end cover respectively arranged at both ends of the valve body. A valve plate is arranged at the bottom of the valve body, and a ceramic slide plate is fixed to the inner side wall of the valve plate. The valve plate and the ceramic slide plate are sequentially provided with a first exhaust port, a first air outlet, an air inlet, a second air outlet and a second exhaust port from left to right. A slider that slides with the ceramic slide plate is arranged in the middle of the valve stem. The slider is in contact with the ceramic slide plate. The side surface where the plates are fitted is provided with a first groove and a second groove for switching the gas circuit; a small piston assembly is provided at the left end of the valve stem, and a large piston is provided at the right end of the valve stem, the pressure area of the small piston assembly is smaller than the pressure area of the large piston, a left chamber is formed between the small piston assembly and the left end cover, a right chamber is formed between the large piston and the right end cover, the valve cavity is connected with the left chamber through a first gas channel and with the right chamber through a second gas channel, respectively, and a pilot assembly for controlling the conduction or cutoff of the second gas channel is also provided on the valve body.

According to the above patent, the above patent sets a slider that slides with the ceramic slide in the middle of the valve stem, and sets a first groove and a second groove on the surface of the slider that fits with the ceramic slide. When the valve stem moves axially under the action of the pressure difference, the slider also moves with the valve stem relative to the ceramic slide, and under the cooperation of the first groove and the second groove, the switching of the air path is realized. However, compared with the flat ring used in the prior art, the above patent is not prone to wear and avoids the occurrence of air leakage. However, although wear and air leakage are reduced, due to the sliding cooperation between the slider and the ceramic slide, and the simple movement and switching mechanism of the first and second grooves, the coaxiality between the slider and the ceramic slide may be difficult to ensure under high pressure difference or frequent operation, thereby causing displacement deviation, affecting the sealing performance and the accuracy of air path switching. Therefore, there is a need for a valve stem sliding structure that can ensure that the sealing is not affected.

Summary of the invention

In view of the problems existing in the prior art, an explosion-proof two-position five-way electromagnetic reversing valve is provided. The present invention seals the valve stem and the valve cavity together in a sliding state through a coaxial sealing assembly, thereby ensuring the sealed transmission of gas in a specific channel inside the valve body and avoiding leakage, and enables the flat ring that cooperates with the sealing ring to be accurately docked together, thereby avoiding sealing failure caused by movement deviation.

In order to solve the problems of the prior art, the present invention provides an explosion-proof two-position five-way electromagnetic reversing valve, including a valve body and a valve stem that is arranged in a valve cavity of the valve body and can move therein, the valve body having an air inlet, a first air outlet, a second air outlet, a first exhaust port and a second exhaust port connected to the interior thereof, the valve body also having an air flow passage that can be connected to the air inlet and extend to both ends of the valve body, and an air guide structure that is respectively arranged at both ends of the valve body and can cooperate with the corresponding air flow passage to push the valve stem to move, a plurality of flat rings are arranged on the valve stem, a plurality of nodes corresponding to the plurality of flat rings are arranged in the valve body, a sealing ring that can contact the corresponding flat ring is provided at each of the nodes, and a coaxial sealing assembly that is slidably connected to the valve cavity of the valve body is provided at both ends of the valve stem, the coaxial sealing assembly is used to keep the contact between the flat ring and the sealing ring precisely aligned and in close contact.

Preferably, the surfaces that can contact each other between the sealing ring and the corresponding flat ring are all inclined fitting surfaces. When the sealing ring and the corresponding flat ring are in contact, the fitting surfaces of the two fit each other so that the passage there is sealed.

Preferably, the coaxial sealing assembly includes a sliding sleeve fixedly mounted on the valve stem and slidably inserted into the valve cavity of the valve body, wherein the sliding sleeve is used to maintain the coaxiality of the valve stem during movement in the valve cavity.

Preferably, the coaxial sealing assembly further comprises a connecting piece arranged between the sliding sleeve and the valve body to ensure that the two are in a sealed state.

Preferably, the connecting member is a flexible structure that can follow the movement of the valve stem and always maintain a sealed state with the valve body.

Preferably, the connecting member is specifically a bag sleeve mounted on the valve stem, one end of the bag sleeve is fixedly connected to the sliding sleeve, and the other end of the bag sleeve is fixedly connected to the valve body. When the valve stem moves, the bag sleeve deforms following the movement of the valve stem, so that the end of the valve stem and the valve body are always in a sealed state.

Preferably, a sliding gap is left between the sliding sleeve and the valve cavity of the valve body, a ball is arranged between the sliding sleeve and the valve body, the ball is in rolling contact with the valve body, and a groove is provided on the outer surface of the sliding sleeve for the ball to be embedded in and rotate in.

Preferably, the outer end of the sleeve has an extension edge extending outward perpendicular to the direction of its circumference, and both ends of the valve body have extension ends that can contact the extension edge of the corresponding sleeve. When the extension edge of the sleeve contacts the extension end, the passage between the air inlet and the first air outlet or the second air outlet is in an open state, and the first exhaust port or the second exhaust port is in a closed state.

Preferably, the gas guide structure has a gas guide end cover fixed at the end of the valve body, and a coil assembly capable of controlling the flow of gas. The end of the valve stem is provided with a piston slidably arranged in the gas guide end cover. The gas guide end cover has a gas guide hole capable of applying compressed gas to the piston, and a control gas hole connected to the flow air channel. When the coil assembly connects the control gas hole with the gas guide hole, the compressed gas enters the gas guide end cover from the flow air channel, the control gas hole and the gas guide hole in turn, so that the piston is pressed and pushed.

Preferably, the coil assembly includes a moving iron core and a stationary iron core, a compression spring is provided between the moving iron core and the stationary iron core, and a boss is provided in the area of the air guide end cover surrounding the control air hole. When the coil assembly is not energized, the compression spring is in a state of not being acted upon by external force. At this time, the moving iron core contacts the boss, so that the control air hole is closed.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention seals both ends of the valve stem with the valve cavity in a sliding state through a coaxial sealing assembly. Even when the valve stem moves repeatedly, it can maintain close contact with the valve cavity wall to prevent gaps caused by vibration or pressure fluctuations, thereby ensuring the sealed transmission of gas in a specific channel inside the valve body and avoiding leakage. It also enables the flat ring that cooperates with the sealing ring to be accurately docked together, avoiding sealing failure due to movement deviation, avoiding wear of the flat ring, and reducing the need for frequent maintenance or replacement due to sealing failure.

2. The present invention increases the sealing contact area and improves the tightness of the seal through the inclined fitting surface between the flat ring and the sealing ring, effectively preventing gas leakage. Compared with the traditional method of abutting the flat ring with the node, the present invention greatly reduces the wear rate of the flat ring, extends the service life of the flat ring, and reduces maintenance costs and replacement frequency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the three-dimensional structure of a flameproof two-position five-way electromagnetic reversing valve.

FIG. 2 is a plan cross-sectional view of a flameproof two-position five-way electromagnetic reversing valve.

FIG. 3 is a cross-sectional view of the three-dimensional structure of a flameproof two-position five-way electromagnetic reversing valve.

Fig. 4 is a cross-sectional view taken along the line A-A in Fig. 2 .

Fig. 5 is a cross-sectional view taken along the line B-B in Fig. 4 .

FIG. 6 is a schematic diagram of a state in which the air inlet and the first air outlet of the explosion-proof two-position five-way electromagnetic reversing valve are connected.

FIG. 7 is a schematic diagram of a state in which the air inlet and the second air outlet of the explosion-proof two-position five-way electromagnetic reversing valve are connected.

FIG. 8 is an enlarged schematic diagram of point C in FIG. 2 .

FIG. 9 is an enlarged schematic diagram of point D in FIG. 2 .

FIG. 10 is an enlarged schematic diagram of point E in FIG. 2 .

FIG. 11 is a plan view of the gas guide structure of the flameproof two-position five-way electromagnetic reversing valve.

The numbers in the figure are: 1. valve body; 11. air inlet; 12. first air outlet; 13. second air outlet; 14. first exhaust port; 15. second exhaust port; 16. air flow duct; 2. valve stem; 21. flat ring; 211. node; 22. sealing ring; 3. air guide end cover; 31. piston; 311. air guide hole; 312. control air hole; 3121. boss; 32. moving iron core; 33. stationary iron core; 34. compression spring; 4. coaxial sealing assembly; 41. sleeve; 411. ball; 412. extension edge; 413. extension end; 42. bag sleeve.

DETAILED DESCRIPTION

In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

Referring to FIGS. 1 to 7 , the flameproof two-position five-way electromagnetic reversing valve comprises a valve body 1 and a valve stem 2 which is arranged in a valve cavity of the valve body 1 and can move therein. The valve body 1 has an air inlet 11, a first air outlet 12, a second air outlet 13, a first exhaust port 14 and a second exhaust port 15 which are connected to the interior thereof. The valve body 1 also has an air flow passage 16 which can be connected to the air inlet 11 and extend to both ends of the valve body 1, and two air flow passages 16 which are arranged at both ends of the valve body 1 and can cooperate with the corresponding air flow passages 16. An air-guiding structure for pushing the valve stem 2 to move, wherein a plurality of flat rings 21 are arranged on the valve stem 2, and a plurality of nodes 211 corresponding to the plurality of flat rings 21 are arranged in the valve body 1, and each of the nodes 211 is provided with a sealing ring 22 capable of contacting the corresponding flat ring 21, and both ends of the valve stem 2 are also provided with a coaxial sealing assembly 4 slidably connected to the valve cavity of the valve body 1, and the coaxial sealing assembly 4 is used to keep the contact of the flat ring 21 and the sealing ring 22 precisely aligned and in close contact.

When the valve body 1 is installed, the air inlet 11 is connected to the working air source. In the initial state, the air inlet 11 is connected to the first air outlet 12, the second air outlet 13 is connected to the second exhaust port 15, and the first exhaust port 14 is in a closed state. When the air guide structure is in action, the passage between the air flow channel 16 and the air guide structure is connected, and part of the compressed gas in the air inlet 11 enters the air guide structure through the air flow channel 16. The air guide structure acts on the valve stem 2 with the compressed gas, so that the valve stem 2 moves under the action of air pressure. At this time, the air inlet 11 is connected to the second air outlet 13, the first exhaust port 14 is connected to the first air outlet 12, and the second exhaust port 15 is in a closed state, thereby realizing the air path reversing operation, that is, during the movement of the valve stem 2, the flat ring 21 thereon contacts and tightly seals with the sealing ring 22 on the node 211 inside the valve body 1. The movement of the valve stem 2 changes the connection relationship between the air ports, resulting in a new connection between the air inlet 11 and the second air outlet 13. The gas circuit is connected, and at the same time, the first exhaust port 14 is opened with the first gas outlet 12 to allow gas to be discharged, and the second exhaust port 15 is closed, thereby realizing the reversing operation of the gas circuit. During the movement of the valve stem 2, the coaxial sealing components 4 at both ends ensure a good sliding seal between the valve stem 2 and the valve cavity of the valve body 1, ensuring that the gas will not leak from the gap between the valve stem 2 and the valve body 1, thereby enhancing the overall air tightness, ensuring the precise contact between the flat ring 21 and the sealing ring 22, and avoiding the flat ring 21 deviating from the position of the sealing ring 22 and causing poor sealing. Even in the case of repeated movement of the valve stem 2, it can maintain close contact with the valve cavity wall to prevent gaps caused by vibration or pressure fluctuations, thereby ensuring the sealed transmission of gas in a specific channel inside the valve body 1 and avoiding leakage. After the gas circuit is switched into place, the gas guide structure stops supplying gas, and the valve stem 2 remains in the new position due to the maintenance of the air pressure, maintaining the reversing state of the gas circuit until the next operation instruction arrives.

6-9 , the surfaces that can contact each other between the sealing ring 22 and the corresponding flat ring 21 are all inclined fitting surfaces. When the sealing ring 22 and the corresponding flat ring 21 are in contact, the fitting surfaces of the two fit each other so that the passage there is sealed.

When the gas guide structure is activated, the valve stem 2 begins to move under the action of air pressure, driving the flat ring 21 connected thereto to move in the direction of the corresponding sealing ring 22. As the valve stem 2 moves, the inclined fitting surface on the flat ring 21 gradually approaches and finally fits with the inclined fitting surface of the sealing ring 22 at the corresponding position inside the valve body 1, ensuring that they can lock with each other with a large contact area and a tight fit at the moment of contact to form a reliable sealing interface. When the sealing ring 22 and the fitting surface of the flat ring 21 are completely fitted, the passage between them is effectively sealed, and the gas path is switched to a predetermined open or closed state, thereby achieving precise control of the airflow direction and preventing gas leakage.

2 , 3 and 10 , the coaxial sealing assembly 4 includes a sleeve 41 fixedly mounted on the valve stem 2 and slidably inserted into the valve cavity of the valve body 1 , and the sleeve 41 is used to maintain the coaxiality of the valve stem 2 during movement in the valve cavity.

During the installation process, the valve stem 2 is inserted into the valve cavity of the valve body 1 together with the sliding sleeve 41. The inner diameter of the sliding sleeve 41 is closely matched with the outer diameter of the valve stem 2. At the same time, the sliding sleeve 41 slides in the valve cavity, so that the valve stem 2 is coaxial with the valve cavity to allow the valve stem 2 to move smoothly without affecting the air tightness. When the valve stem 2 moves axially under the action of air pressure, the sliding sleeve 41 slides with the valve stem 2 to ensure that the moving path of the valve stem 2 is consistent with the central axis of the valve body 1, that is, the coaxiality is maintained, so that the contact between the flat ring 21 and the sealing ring 22 remains coaxial, thereby improving the sealing effect.

2 , 3 and 10 , the coaxial sealing assembly 4 further includes a connecting piece disposed between the sliding sleeve 41 and the valve body 1 to ensure that the two are in a sealed state.

As the sleeve 41 slides along the valve cavity driven by the valve stem 2, the connector seals the sleeve 41 and the valve body 1, forming a reliable sealing interface and effectively preventing gas from leaking from the tiny gap between the sleeve 41 and the valve body 1.

2 , 3 and 10 , the connecting member is a flexible structure that can follow the movement of the valve stem 2 and always maintain a sealed state with the valve body 1 .

When the valve stem 2 moves axially, the flexible connector moves with the valve stem 2. No matter what position the valve stem 2 is in, the connector can conform to the internal contour of the valve body 1 through its own deformation to form a continuous and tight sealing interface, ensuring that even during the dynamic process of the movement of the valve stem 2, air tightness can be maintained to prevent gas leakage.

Referring to Figures 2, 3 and 10, the connecting piece is specifically a bag sleeve 42 mounted on the valve stem 2, one end of the bag sleeve 42 is fixedly connected to the sliding sleeve 41, and the other end of the bag sleeve 42 is fixedly connected to the valve body 1. When the valve stem 2 moves, the bag sleeve 42 deforms following the movement of the valve stem 2, so that the end of the valve stem 2 and the valve body 1 are always in a sealed state.

When the valve stem 2 moves axially along the valve body 1, the bag sleeve 42 moves accordingly and undergoes necessary deformation, which can adapt to the length change of the valve stem 2 during the movement while maintaining a close fit with the contact part of the valve body 1. Due to the deformation ability of the bag sleeve 42, even if the valve stem 2 is in motion, the two ends of the bag sleeve 42 can ensure a reliable seal between the end of the valve stem 2 and the valve body 1, effectively preventing gas leakage. Compared with hard contact, the direct friction between the valve stem 2 and the valve body 1 is reduced, thereby reducing wear.

As shown in Figures 2, 3 and 10, a sliding gap is left between the sleeve 41 and the valve cavity of the valve body 1, a ball 411 is provided between the sleeve 41 and the valve body 1, and the ball 411 is in rolling contact with the valve body 1. The outer surface of the sleeve 41 is provided with a groove for the ball 411 to be embedded in and rotate in.

When the sleeve 41 moves along the valve cavity, the ball 411 rolls along the inner wall of the valve body 1, avoiding friction between the valve stem 2 and the valve body 1. While maintaining the sliding gap, the existence of the ball 411 also provides support for the movement of the sleeve 41, thereby ensuring the coaxiality between the valve stem 2 and the valve body 1 and improving the stability of the valve stem 2 during movement.

Referring to Figures 2, 3 and 10, the outer end of the sleeve 41 has an extension edge 412 extending outward perpendicular to the circumference thereof, and both ends of the valve body 1 have extension ends 413 that can contact the extension edge 412 of the corresponding sleeve 41. When the extension edge 412 of the sleeve 41 contacts the extension end 413, the passage between the air inlet 11 and the first air outlet 12 or the second air outlet 13 is in an open state, and at the same time the first exhaust port 14 or the second exhaust port 15 is in a closed state.

When the valve stem 2 drives the sleeve 41 to move to a specific position along the valve cavity, the extended edge 412 of the sleeve 41 will contact the extended end 413 of the valve body 1. At this time, the air inlet 11 and the first air outlet 12 or the second air outlet 13 will be connected, and the first exhaust port 14 or the second exhaust port 15 will be closed due to the sealing effect, so as to flexibly control the opening and closing of the air path and ensure the accurate switching of the airflow direction.

Referring to Figures 2, 3 and 11, the gas guide structure has a gas guide end cover 3 fixed at the end of the valve body 1, and a coil assembly capable of controlling the flow of gas. The end of the valve stem 2 is provided with a piston 31 slidably arranged in the gas guide end cover 3. The gas guide end cover 3 has a gas guide hole 311 capable of applying compressed gas to the piston 31, and a control gas hole 312 connected to the flow air channel 16. When the coil assembly connects the control gas hole 312 with the gas guide hole 311, the compressed gas enters the gas guide end cover 3 from the flow air channel 16, the control gas hole 312 and the gas guide hole 311 in sequence, so that the piston 31 is pressed and pushed.

When the coil assembly receives an electrical signal and is energized, the structure inside the coil assembly changes under the action of electromagnetic force, causing the passage between the control air hole 312 and the air guide hole 311 to be opened. As the control air hole 312 is opened, part of the compressed gas flows in from the flow channel 16, passes through the control air hole 312, and then passes through the air guide hole 311, directly acting on the piston 31. The gas pressure pushes the piston 31 to move along the inside of the air guide end cover 3, thereby driving the valve stem 2 to move. As the valve stem 2 moves, the air path configuration inside the valve body 1 changes, thereby realizing the switching of the air path. When the electromagnetic drive instruction ends, the coil assembly is powered off, the passage between the control air hole 312 and the air guide hole 311 is closed, and the coil assembly at the other end of the valve body 1 is energized, so that the compressed gas enters the corresponding air guide end cover 3, impacting the piston 31 there, causing the air path to switch again, completing a complete air path switching cycle.

Referring to Figures 2, 3 and 11, the coil assembly includes a moving iron core 32 and a stationary iron core 33, a compression spring 34 is provided between the moving iron core 32 and the stationary iron core 33, and a boss 3121 is provided in the area of the air guide end cover 3 surrounding the control air hole 312. When the coil assembly is not energized, the compression spring 34 is in a state of not being acted upon by external force. At this time, the moving iron core 32 is in contact with the boss 3121, so that the control air hole 312 is closed.

The specific working process of the coil assembly is as follows: when the moving iron core 32 and the static iron core 33 are not energized, the compression spring 34 is in a state of not being acted upon by external force. At this time, the moving iron core 32 contacts the boss 3121 on the air guide end cover 3, ensuring that the control air hole 312 is closed, preventing the airflow from the flow channel 16 through the control air hole 312 and along the air guide hole 311 into the interior of the air guide end cover 3, and the air path maintains the initial state, that is, maintaining the current air path configuration unchanged, such as the connection state between the air inlet 11 and the first air outlet 12 or the second air outlet 13. When the moving iron core 32 and the static iron core 33 are energized, the moving iron core 32 moves away from the convex strip, and the compression spring 34 is compressed. At this time, the control air hole 312 is opened, allowing the gas in the flow channel 16 to act on the piston 31 through the control air hole 312 and the air guide hole 311 in turn, thereby moving the valve stem 2 to achieve air path switching.

The present invention seals the valve stem 2 and the valve cavity together in a sliding state through the coaxial sealing assembly 4, and even when the valve stem 2 moves repeatedly, it can maintain close contact with the valve cavity wall to prevent gaps caused by vibration or pressure fluctuations, thereby ensuring the sealed transmission of gas in a specific channel inside the valve body 1 and avoiding leakage, and enabling the flat ring 21 that cooperates with the sealing ring 22 to be accurately docked together, avoiding sealing failure due to movement deviation, avoiding wear of the flat ring 21, and reducing the need for frequent maintenance or replacement due to sealing failure.

The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims (10)

1. An explosion-proof two-position five-way electromagnetic reversing valve, comprising a valve body (1) and a valve stem (2) arranged in a valve cavity of the valve body (1) and capable of moving, the valve body (1) having an air inlet (11), a first air outlet (12), a second air outlet (13), a first exhaust port (14) and a second exhaust port (15) communicating with the interior thereof, the valve body (1) also having an air flow passage (16) capable of communicating with the air inlet (11) and extending to two ends of the valve body (1), and air guide structures respectively arranged at two ends of the valve body (1) and capable of cooperating with the corresponding air flow passage (16) to push the valve stem (2) to move; The valve stem (2) is characterized in that a plurality of flat rings (21) are provided on the valve stem (2), a plurality of nodes (211) corresponding to the plurality of flat rings (21) are provided in the valve body (1), each of the nodes (211) is provided with a sealing ring (22) capable of contacting the corresponding flat ring (21), and both ends of the valve stem (2) are also provided with a coaxial sealing assembly (4) slidably connected to the valve cavity of the valve body (1), and the coaxial sealing assembly (4) is used to maintain the contact between the flat ring (21) and the sealing ring (22) in precise alignment and tight contact. 2. The flameproof two-position five-way electromagnetic reversing valve according to claim 1 is characterized in that the surfaces that can contact each other between the sealing ring (22) and the corresponding flat ring (21) are all inclined fitting surfaces, and when the sealing ring (22) and the corresponding flat ring (21) are in contact, the fitting surfaces of the two fit each other, so that the passage at that location is sealed. 3. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 1 is characterized in that the coaxial sealing assembly (4) includes a sliding sleeve (41) fixedly mounted on the valve stem (2) and slidably inserted into the valve cavity of the valve body (1), and the sliding sleeve (41) is used to maintain the coaxiality of the valve stem (2) during its movement in the valve cavity. 4. The flameproof two-position five-way electromagnetic reversing valve according to claim 3 is characterized in that the coaxial sealing assembly (4) further comprises a connecting piece arranged between the sliding sleeve (41) and the valve body (1) to ensure that the two are in a sealed state. 5. The flameproof two-position five-way electromagnetic directional valve according to claim 4, characterized in that the connecting piece is a flexible structure that can follow the movement of the valve stem (2) and always maintain a sealed state with the valve body (1). 6. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 5 is characterized in that the connecting piece is specifically a bag sleeve (42) sleeved on the valve stem (2), one end of the bag sleeve (42) is fixedly connected to the sliding sleeve (41), and the other end of the bag sleeve (42) is fixedly connected to the valve body (1), when the valve stem (2) moves, the bag sleeve (42) deforms following the movement of the valve stem (2), so that the end of the valve stem (2) and the valve body (1) are always in a sealed state. 7. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 3 is characterized in that a sliding gap is left between the sliding sleeve (41) and the valve cavity of the valve body (1), a ball (411) is provided between the sliding sleeve (41) and the valve body (1), the ball (411) and the valve body (1) are in rolling contact, and the outer surface of the sliding sleeve (41) is provided with a groove in which the ball (411) is embedded and can rotate. 8. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 7 is characterized in that the outer end of the sleeve (41) has an extension edge (412) extending outward perpendicular to the circumferential direction of the sleeve, and both ends of the valve body (1) have extension ends (413) that can contact the extension edge (412) of the corresponding sleeve (41), and when the extension edge (412) of the sleeve (41) contacts the extension end (413), the passage between the air inlet (11) and the first air outlet (12) or the second air outlet (13) is in an open state, and at the same time, the first exhaust port (14) or the second exhaust port (15) is in a closed state. 9. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 1 is characterized in that the air guide structure has an air guide end cover (3) fixed to the end of the valve body (1), and a coil assembly capable of controlling the flow of gas, the end of the valve stem (2) is provided with a piston (31) slidably arranged in the air guide end cover (3), the air guide end cover (3) has an air guide hole (311) capable of causing compressed gas to act on the piston (31), and has a control air hole (312) connected to the flow air channel (16), when the coil assembly connects the control air hole (312) with the air guide hole (311), the compressed gas enters the air guide end cover (3) from the flow air channel (16), the control air hole (312) and the air guide hole (311) in sequence, so that the piston (311) is pressed and pushed. 10. The explosion-proof two-position five-way electromagnetic reversing valve according to claim 9 is characterized in that the coil assembly includes a moving iron core (32) and a stationary iron core (33), a compression spring (34) is provided between the moving iron core (32) and the stationary iron core (33), and a boss (3121) is provided in the area of the air guide end cover (3) surrounding the control air hole (312). When the coil assembly is not energized, the compression spring (34) is in a state of not being acted upon by external force, and at this time, the moving iron core (32) is in contact with the boss (3121), so that the control air hole (312) is closed.