Disassembly touch locking method and safety mechanism for underground automatic explosive-proof device
By employing a mutually interlocking design between the protective housing safety pin and the triggering device safety pin, combined with threaded connections and specialized tools, the problems of loosening, accidental triggering, and tampering in traditional downhole automatic explosion-proof devices have been solved, achieving high safety and reliability in downhole operations.
Patent Information
- Application Number
- CN202511930666.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-19
- Publication Date
- 2026-03-17
AI Technical Summary
The safety mechanism of traditional underground automatic explosion-proof devices is prone to loosening, accidental triggering, and tampering, and lacks locking protection during disassembly, posing safety hazards.
The design employs a locking mechanism between the protective housing safety pin and the trigger device safety pin. Through threaded connections and spring washers to prevent loosening, it ensures that at least one safety pin is always locked. Non-standard threads and special tools are used for connection to prevent misoperation and tampering.
It improves the safety and reliability of insurance institutions, prevents accidental triggering and waste of resources, ensures the safety of downhole operations, and reduces the risk of accidents.
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Figure CN121676010A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of explosion-proof safety in underground coal mines, specifically to a method for disassembling and locking an automatic explosion-proof device in underground mines and a safety mechanism. Background Technology
[0002] The underground working environment in coal mines is complex, and gas and coal dust explosions are among the main safety threats. Automatic explosion-proof devices (AEDs) are widely used in coal mines and metal and non-metal mine roadways as a key protective device. Their core function is to receive the shock wave in the early stages of an explosion, convert it into axial motion, trigger the release of high-pressure gas, and instantly spray out extinguishing media (such as dry powder or water mist) to form an explosion barrier, extinguish the explosion flames, and prevent the propagation of shock waves and flames, thereby preventing the disaster from escalating and protecting the safety of personnel and equipment underground.
[0003] Traditional automatic explosion-proof devices for downhole drilling typically include a shock wave receiver, a trigger rod, a safety pin, and a extinguishing agent injection port. In standby mode, the device locks the trigger via a safety mechanism to prevent accidental triggering. When an explosion occurs, the shock wave pushes the trigger rod to release the safety, releasing the extinguishing agent. However, traditional safety mechanisms have significant drawbacks. First, the safety pin is usually locked only by inserting its tip into a sleeve, lacking anti-loosening measures. It is prone to detachment during downhole vibration, impact, or transportation, leading to safety failure and potential accidental triggering of the device in non-explosive situations, wasting extinguishing agents or causing secondary accidents. Second, traditional safety mechanisms fail to achieve "disassembly-touch interlocking," meaning that the locking state of the trigger during disassembly or maintenance depends on the operator's safety awareness and responsibility, introducing uncertainty. For example, if the operator does not insert the safety pin correctly, the device may be accidentally triggered during handling, causing personal injury or equipment damage. Furthermore, traditional safety pins can be easily removed by external tools, posing a risk of tampering and further reducing safety. Summary of the Invention
[0004] In view of this, the purpose of the present invention is to solve the above problems and provide a method for disassembling and locking an automatic explosion-proof device in wells and a safety mechanism.
[0005] To achieve the above objectives, the present invention provides the following technical solution: A safety mechanism for an automatic explosion-proof device for downhole mining includes a protective shell, a protective shell safety pin, a triggering device safety pin, a force transmission rod, and a bushing; the force transmission rod is slidably disposed within the bushing, and the bushing is threadedly connected to the protective shell; The force transmission rod is provided with a first limiting hole that penetrates radially, the bushing is provided with a second limiting hole that penetrates radially, and the protective shell is provided with a third limiting hole that penetrates radially. The first limiting hole, the second limiting hole, and the third limiting hole are coaxial. The second limiting hole has an internal thread Mb at one end near the protective shell safety pin, and both the trigger device safety pin and the protective shell safety pin have external threads mb that match the internal thread Mb; the front ends of the protective shell safety pin and the trigger device safety pin have connecting parts, and can be detachably connected through the connecting parts. The protective shell safety pin and the trigger device safety pin are interlocked. When either the protective shell safety pin or the trigger device safety pin is screwed in, the other safety pin is pushed out through the connecting part, ensuring that one safety pin is always in the locked state. When the trigger device safety pin is screwed in, the trigger device safety pin is screwed from one end of the third limiting hole into the second limiting hole and the first limiting hole. The external thread mb on the trigger device safety pin is connected to the internal thread Mb, and neither end of the trigger device safety pin protrudes from the outer cylindrical surface of the bushing, so that the force transmission rod is fixed and locked to the bushing. When the protective housing safety pin is screwed in, the protective housing safety pin is screwed into the second limiting hole from the other end of the third limiting hole. The external thread mb on the protective housing safety pin is connected to the internal thread Mb, and the protective housing safety pin does not extend into the first limiting hole, so that the protective housing and the bushing are fixedly locked.
[0006] Furthermore, the connection between the protective shell safety pin and the front end of the trigger device safety pin is a connecting thread, where one is an internal thread Mc and the other is a corresponding external thread mc.
[0007] Furthermore, both the protective shell safety pin and the trigger device safety pin are T-shaped, and the second and third limiting holes are stepped holes. The axial position of the protective shell safety pin and the trigger device safety pin is restricted by the large end face of the T-shape cooperating with the stepped end face of the stepped hole. Both the protective housing safety pin and the trigger device safety pin are fitted with spring washers. The spring washers are located between the large end face of the T-shaped part and the stepped end face of the stepped hole, providing a reverse force to prevent the threads from loosening.
[0008] Furthermore, both the protective housing safety pin and the trigger device safety pin have tool connecting parts at their tail ends, and are connected to disassembly and assembly tools through the tool connecting parts.
[0009] Furthermore, the tool connection part at the tail end of the protective shell safety pin and the trigger device safety pin are both internally threaded Ma. Utilizing the unidirectional action of the thread, the two safety pins can only achieve the disassembly and locking function by using disassembly and assembly tools, and neither safety pin can be disassembled individually.
[0010] Furthermore, the internal thread Ma is a standard thread.
[0011] Furthermore, both the internal thread Mb and the external thread mb are standard threads.
[0012] Furthermore, both the internal thread Mc and the external thread mc are non-standard threads.
[0013] A method for disassembling and locking an automatic explosion-proof device in a well, employing the safety mechanism described above, includes the following steps: In the transport state, the trigger device safety pin is screwed from one end of the third limiting hole into the second limiting hole and the first limiting hole, so that the external thread mb on the trigger device safety pin is connected with the internal thread Mb on the second limiting hole, ensuring that the two ends of the trigger device safety pin do not protrude from the outer cylindrical surface of the bushing, and locking the force transmission rod and the bushing. In the installation state, first put the protective shell into the force transmission rod and screw it into the bushing through the thread. Then, screw the protective shell safety pin into the second limit hole from the other end of the third limit hole, so that the external thread mb on the protective shell safety pin is connected with the internal thread Mb on the second limit hole. At the same time, connect the trigger device safety pin through the connecting part and push the trigger device safety pin out to lock the protective shell and unlock the trigger device. During operation, the protective casing remains locked to prevent disassembly; In the disassembled state, screw the trigger device safety pin into the first and second limit holes from one end of the third limit hole, so that the external thread mb on the trigger device safety pin is connected to the internal thread Mb on the second limit hole. At the same time, the protective shell safety pin is connected through the connecting part, and the protective shell safety pin is pushed out, so that the protective shell can only be unlocked after the trigger device is locked.
[0014] Furthermore, the screwing in and unscrewing out operations of the protective shell safety pin and the trigger device safety pin are both performed by connecting the tool connection part at the tail end of the protective shell safety pin and the trigger device safety pin to the disassembly tool.
[0015] Furthermore, during any state switch, ensure that at least one of the protective housing safety pin and the trigger device safety pin locks the second limit hole to prevent accidental unlocking or false triggering.
[0016] The beneficial effects of this invention are as follows: This invention has significant advantages over traditional technologies: 1. High safety and reliability: The safety pin of the triggering device passes completely through the force transmission rod, and combined with the spring pad anti-loosening design, it significantly improves the safety margin of the safety mechanism. Even in environments with strong downhole vibrations, the safety pin can remain stably locked, avoiding resource waste or secondary accidents caused by accidental triggering.
[0017] 2. Interlocking Function: The interlocking design of the protective housing safety pin and the trigger device safety pin ensures that one safety pin is always locked when screwed in, as screwing in one pin pushes the other out. During operation, the protective housing is locked to prevent disassembly; during disassembly, the trigger device must be locked before the protective housing can be unlocked, eliminating the risk of accidental triggering due to operator negligence and ensuring safety during downhole operations.
[0018] 3. Tamper-proof and operational standardization: The safety pin's connecting part uses a non-standard thread Mc / mc, while the tool connecting part uses a standard internal thread Ma, allowing operation only with specialized tools to prevent unauthorized disassembly or tampering. The T-shaped safety pin mates with the stepped hole to restrict axial movement, further enhancing structural stability.
[0019] In summary, this invention effectively solves the problems of safety and interlocking uncertainty in traditional safety mechanisms, improves device reliability, reduces accident risks, and provides a solid guarantee for downhole safety.
[0020] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description
[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a diagram showing the installation status of the protective shell safety pin in this invention.
[0022] Figure 2 This is a diagram showing the installation status of the safety pin of the triggering device in this invention.
[0023] Figure 3 This is a schematic diagram of the bushing structure in this invention.
[0024] Figure 4 This is a schematic diagram of the protective shell in this invention.
[0025] Figure 5 This is a schematic diagram of the protective shell safety pin in this invention.
[0026] Figure 6 This is a schematic diagram of the safety pin of the triggering device in this invention.
[0027] Reference numerals: 1-Protective shell; 2-Spring washer; 3-Protective shell safety pin; 4-Trigger device safety pin; 5-Spring washer; 6-Force transmission rod; 7-Shaft sleeve; 8-Connecting nut. Detailed Implementation
[0028] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0029] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.
[0030] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention 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. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.
[0031] Example 1 like Figures 1-6 As shown, this embodiment provides a method for disassembling and locking an automatic explosion-proof device in underground mines and a safety mechanism, which is suitable for rapid explosion-proof protection against gas or coal dust explosions in underground coal mine roadways. The safety mechanism includes a protective shell 1, a spring pad 2, a protective shell safety pin 3, a triggering device safety pin 4, a spring pad 5, a force transmission rod 6, a bushing 7, and a connecting nut 8.
[0032] The force transmission rod 6 is slidably disposed within the bushing 7, which is connected to the protective shell 1 via an external thread md and an internal thread Md. The force transmission rod 6 has a first radially penetrating limiting hole, the bushing 7 has a second radially penetrating limiting hole, and the protective shell 1 has a third radially penetrating limiting hole. The first, second, and third limiting holes are coaxial. The end of the second limiting hole near the protective shell safety pin 3 has an internal thread Mb, and both the protective shell safety pin 3 and the trigger device safety pin 4 have external threads mb that match the internal thread Mb. The front ends of the protective shell safety pin 3 and the trigger device safety pin 4 have connecting parts, which can be detachably connected via the connecting parts (one with an internal thread Mc and the other with a corresponding external thread mc, preferably a non-standard thread) to achieve mutual locking. Both the protective shell safety pin 3 and the trigger device safety pin 4 are T-shaped, and the second and third limiting holes are stepped holes. The large end face of the T-shape mates with the stepped end face of the stepped hole, restricting the axial position of the safety pin. Spring washers 2 and 5 are respectively fitted onto the protective housing safety pin 3 and the trigger device safety pin 4, located between the large end face of the T-shaped pin and the stepped end face of the stepped hole, providing a counterforce to prevent loosening of the threads. The tail end of the safety pin is provided with a tool connection part (internal thread Ma, preferably a standard thread), which allows only special tools to be connected for operation.
[0033] In the factory and shipping condition: the trigger device safety pin 4 is screwed into the second and first limit holes from one end of the third limit hole, with the external thread mb connected to the internal thread Mb, and neither end protruding from the outer cylindrical surface of the bushing 7, locking the force transmission rod 6 to the bushing 7 to prevent the trigger device from malfunctioning. The protective shell 1 can rotate relative to the bushing 7, facilitating transportation and initial assembly.
[0034] In the downhole installation and operation state: First, fit the protective shell 1 onto the force transmission rod 6 and screw it into the bushing 7 via threads. Connect the two force transmission rods 6 using the connecting nut 8. Then, screw the protective shell safety pin 3 into the second limit hole from the other end of the third limit hole, with the external thread mb connecting to the internal thread Mb, but not extending into the first limit hole. Simultaneously, push the trigger device safety pin 4 out through the connecting part (Mc / mc), thus fixing and locking the protective shell 1 and the bushing 7, and unlocking and unlocking the force transmission rod 6. The protective shell 1 covers the connecting nut 8 to prevent disassembly during operation.
[0035] In the disassembly state: the trigger device safety pin 4 is screwed into the first and second limit holes from one end of the third limit hole. The external thread mb is connected to the internal thread Mb. The two ends do not protrude from the outer cylindrical surface of the bushing 7. At the same time, the protective shell safety pin 3 is pushed out through the connecting part (Mc / mc). The protective shell 1 can only be unlocked after the force transmission rod 6 is locked with the bushing 7, which facilitates safe disassembly.
[0036] The specific usage method of this embodiment is as follows: The device is shipped in transport condition with the trigger device safety pin 4 locked. Before downhole installation, the condition is checked using a special tool via the tool connection section (Ma). First, assemble the force transmission rod 6 and bushing 7, and connect the multiple sections of the force transmission rod 6 using the connecting nut 8. Screw the protective shell 1 into the bushing 7, then screw in the protective shell safety pin 3, simultaneously pushing out the trigger device safety pin 4. After installation, the device enters the operating state, and the protective shell 1 is locked to prevent disassembly. In the event of an explosion, the shock wave drives the force transmission rod 6 to move axially, triggering the explosion-proof mechanism to release the extinguishing medium. During disassembly, the trigger device safety pin 4 must be screwed in to lock the force transmission rod 6 before the protective shell safety pin 3 can be unscrewed to disassemble the protective shell 1 and connecting nut 8.
[0037] Example 2 like Figures 1-6 As shown, this embodiment provides a method for disassembling and locking an automatic explosion-proof device in underground mines and a safety mechanism, which is suitable for metal and non-metal mines or environments with higher vibration intensity. The structure is basically the same as that of Embodiment 1, including a protective shell 1, a spring pad 2, a protective shell safety pin 3, a trigger device safety pin 4, a spring pad 5, a force transmission rod 6, a bushing 7, and a connecting nut 8. The difference lies in the material reinforcement and size adjustment to improve durability.
[0038] The core structure of the safety mechanism is the same as in Example 1. The internal thread Mb and external thread mb of the second limiting hole are reinforced standard threads, while the connecting part Mc / mc is a high-strength non-standard thread. The force transmission rod 6, bushing 7, and protective shell 1 are made of corrosion-resistant high-strength alloy steel (e.g., with added chromium and molybdenum). The outer diameter of bushing 7 is increased to 80mm, and the diameter of force transmission rod 6 is increased to 50mm to withstand higher impacts. Spring pads 2 and 5 are made of high-elasticity stainless steel, increasing the reverse force by 20%. The large end diameter of the T-shaped safety pin is increased to 40mm, and the stepped hole is correspondingly enlarged to ensure more stable axial restraint. The tool connecting part Ma has a deepened standard internal thread for easy operation with heavy-duty special tools.
[0039] The operating logic for the factory and transportation status, installation and operation status, and disassembly status is the same as that in Example 1, but due to the material reinforcement, it is suitable for environments with higher vibration frequencies (such as blasting operation areas in metal mines).
[0040] Specific usage instructions: The device is suitable for mines with wider roadways. Before installation, confirm the transport condition and ensure it is securely locked. During assembly, use connecting nut 8 to connect the reinforced force transmission rod 6 and screw in the enlarged protective shell 1. During operation, the protective shell 1 locks and covers the connecting nut 8. During disassembly, enforce the interlocking sequence to ensure safety.
[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.
Claims
1. A safety mechanism for an automatic flameproof device in a well, c h a r a c t e r i s e d in that It comprises a protective shell, a protective shell safety pin, a trigger device safety pin, a force transmission rod and a shaft sleeve; the force transmission rod is slidably arranged in the shaft sleeve, and the shaft sleeve is threadedly connected to the protective shell; A first limiting hole is formed in the force transmission rod in a radial direction, a second limiting hole is formed in the shaft sleeve in a radial direction, and a third limiting hole is formed in the protective shell in a radial direction; the first limiting hole, the second limiting hole and the third limiting hole are coaxial; An inner thread Mb is formed on one end of the second limiting hole close to the protective shell safety pin, and an outer thread mb matching the inner thread Mb is formed on the trigger device safety pin and the protective shell safety pin; a connecting portion is formed on the front end of the protective shell safety pin and the trigger device safety pin, and the protective shell safety pin and the trigger device safety pin are detachably connected through the connecting portion; The protective shell safety pin and the trigger device safety pin are interlocked, and when any one of the protective shell safety pin and the trigger device safety pin is screwed in, the other one is pushed out through the connecting portion, so that one of the protective shell safety pin and the trigger device safety pin is always in a locked state; When the trigger device safety pin is screwed in, the trigger device safety pin is screwed into the second limiting hole and the first limiting hole from one end of the third limiting hole, the outer thread mb on the trigger device safety pin is connected with the inner thread Mb, and the outer cylindrical surface of the shaft sleeve is not exposed at both ends of the trigger device safety pin, so that the force transmission rod and the shaft sleeve are fixed and locked; When the protective shell safety pin is screwed in, the protective shell safety pin is screwed into the second limiting hole from the other end of the third limiting hole, the outer thread mb on the protective shell safety pin is connected with the inner thread Mb, and the protective shell safety pin does not extend into the first limiting hole, so that the protective shell and the shaft sleeve are fixed and locked.
2. The insurance mechanism of claim 1, wherein, The connecting portion at the front end of the protective shell safety pin and the trigger device safety pin is a connecting thread, and when one of them is an inner thread Mc, the other is an outer thread mc corresponding to the inner thread Mc.
3. The insurance mechanism of claim 2, wherein, The protective shell safety pin and the trigger device safety pin are both T-shaped, and the second limiting hole and the third limiting hole are both stepped holes; the axial position of the protective shell safety pin and the trigger device safety pin is limited by the cooperation between the large end face of the T-shaped structure and the stepped end face of the stepped hole; A spring washer is sleeved on the protective shell safety pin and the trigger device safety pin, and the spring washer is located between the large end face of the T-shaped structure and the stepped end face of the stepped hole, so as to provide a reverse force and prevent the thread from loosening.
4. The insurance mechanism of claim 1, wherein, Tool connecting portions are formed at the tail ends of the protective shell safety pin and the trigger device safety pin, and the tool connecting portions are connected with a dismounting tool.
5. The insurance mechanism of claim 2, wherein, The tool connecting portions at the tail ends of the protective shell safety pin and the trigger device safety pin are both inner threads Ma.
6. The insurance agency of claim 5, wherein, The inner thread Ma is a standard thread.
7. The insurance mechanism of claim 1, wherein, The inner thread Mb and the outer thread mb are both standard threads.
8. The insurance mechanism of claim 2, wherein, The inner thread Mc and the outer thread mc are both non-standard threads.
9. A method for de-energizing lockout of an underground flameproof apparatus, characterized by, The safety mechanism of any one of claims 1-8 comprises the following steps: In the transportation state, the trigger device safety pin is screwed into the second limiting hole and the first limiting hole from one end of the third limiting hole, so that the outer thread mb on the trigger device safety pin is connected with the inner thread Mb on the second limiting hole, and the axial position of the trigger device safety pin is limited by the cooperation between the large end face of the T-shaped structure and the stepped end face of the stepped hole, so as to ensure that the outer cylindrical surface of the shaft sleeve is not exposed at both ends of the trigger device safety pin, and the force transmission rod and the shaft sleeve are locked; In the installation state, the protective shell is sleeved on the force transmission rod and screwed into the shaft sleeve, then the protective shell safety pin is screwed into the second limiting hole from the other end of the third limiting hole, the outer thread mb on the protective shell safety pin is connected with the inner thread Mb on the second limiting hole, the trigger device safety pin is connected through the connecting part, and the trigger device safety pin is pushed out to achieve the locking of the protective shell and the unlocking of the trigger device; In the running state, the protective shell is locked to prevent disassembly; In the disassembly state, the trigger device safety pin is screwed into the first limiting hole and the second limiting hole from one end of the third limiting hole, the outer thread mb on the trigger device safety pin is connected with the inner thread Mb on the second limiting hole, the protective shell safety pin is connected through the connecting part, and the protective shell safety pin is pushed out to achieve the locking of the trigger device and the unlocking of the protective shell.
10. The disengagement locking method according to claim 9, wherein The screwing and unscrewing operations of the protective shell safety pin and the trigger device safety pin are performed through the tool connecting part at the tail end of the protective shell safety pin and the trigger device safety pin and the disassembly tool.
11. The do-not-touch lockout method of claim 9, wherein, In any state switching, at least one of the protective shell safety pin and the trigger device safety pin is locked in the second limiting hole to prevent accidental unlocking or accidental triggering.