A low-resistance one-way flap type explosion-proof valve and control method thereof

Abstract

The present invention discloses a low-resistance one-way flap type explosion-proof valve and a control method thereof, wherein the low-resistance one-way flap type explosion-proof valve comprises a valve body, a valve disc, a lever and a counterweight hammer; the two ends of the valve body are respectively provided with an air inlet and an air outlet, the valve disc is hinged in the valve body through a rotating shaft, the middle part of the lever is fixedly connected to one end of the rotating shaft and the lever is located outside the valve body; the counterweight hammer is connected to the upper end of the lever, and the lever is driven to swing by the counterweight hammer, so that the valve disc is closed between the air inlet and the air outlet; it also includes an instant start mechanism, which comprises an explosion-proof telescopic tube, a gas generator and a driving arm; the driving arm is fixed to the other end of the rotating shaft and the driving arm is located outside the valve body, the outer surface of the valve body is provided with a fixed baffle, the two ends of the explosion-proof telescopic tube are respectively sealed and connected to the driving arm and the baffle, and the gas generator is installed in the explosion-proof telescopic tube. The present invention overcomes the problem that the valve disc position is too high, resulting in a delay in closing the valve disc or failure to reset.

Description

Technical Field

[0001] The invention belongs to the technical field of explosion-proof valves, and in particular relates to a low-resistance one-way flap type explosion-proof valve and a control method thereof. Background Art

[0002] The one-way explosion-proof valve is a commonly used valve device that can block the flame and pressure wave generated by the explosion from propagating in the pipeline. The one-way explosion-proof valve mainly includes valve body, valve disc, bearing, counterweight hammer and other components. Among them, the valve disc is the key component to realize the blocking function. The valve disc is linked with the counterweight hammer through a lever. In the case of positive ventilation, the positive wind pressure pushes the valve disc open and causes the lever to drive the counterweight hammer to swing a certain angle, presenting a positive conduction state. If an explosion occurs, when the impact force of the explosion moves in the opposite direction along the pipeline to the valve disc, it pushes the valve disc in the opposite direction to close, and the reverse closing process will still be reset by the lever driving the counterweight hammer to swing in the opposite direction. In addition, under normal circumstances, the fan stops supplying air to the air duct, and the gravity of the counterweight hammer drives the valve disc to close in the opposite direction, and the one-way explosion-proof valve is in a normally closed state.

[0003] A qualified one-way explosion-proof valve can respond in time, that is, the valve disc closes in time to block the flame. After an explosion, the shock wave propagates faster than the flame, and the power that drives the valve disc to swing in the opposite direction is actually the shock wave or reverse airflow, not the flame. There is a time difference between the shock wave and the flame, and the one-way explosion-proof valve uses this time difference to effectively block the flame from entering the pipeline source or workshop by closing before the flame reaches the valve disc. On the contrary, if the valve disc is not closed or part of the flame passes through the one-way explosion-proof valve, the one-way explosion-proof valve is unqualified.

[0004] The factors that affect the response time of the one-way explosion-proof valve are as follows:

[0005] Factor 1: In the open state, the position of the valve disc is too high or too high. When the shock wave or reverse airflow reaches the valve disc, the pressure on the valve disc is slightly greater than the pressure on the bottom of the valve disc. In this case, the valve disc can be closed, but there is a delay in closing, causing part of the flame to pass through the one-way explosion-proof valve. The pressure on the valve disc is less than or equal to the pressure on the bottom of the valve disc. In this case, the valve disc cannot be closed, or the closing is seriously delayed, causing the flame to pass directly through the one-way explosion-proof valve.

[0006] For factor one, the existing method is to add a limit rod in the valve body, and the length of the limit rod is inversely proportional to the maximum angle of the valve disc opening. Generally, manufacturers will provide reference values ​​or calculation methods for the length of the limit rod, or determine the optimal limit rod length based on actual testing and debugging. In order to shorten the response time and improve the safety factor, the actual length of the limit rod is longer than the theoretical length. However, the longer the limit rod, the greater the wind resistance formed by the valve disc in the valve body, that is, the greater the resistance caused by the one-way explosion-proof valve in the pipeline. Therefore, the response speed (safety factor) of the existing one-way explosion-proof valve is inversely proportional to the ventilation performance, and the two cannot be achieved at the same time. Especially in flammable and explosive industries such as coal mines and dust, the response time is required to be no more than 30 milliseconds, and low wind resistance is required to reduce the load of the forward fan.

[0007] Factor 2: When the valve disc moves from the open state to the closed state, the shock wave or reverse airflow pushes the valve disc to close. The lever needs to drive the counterweight hammer to swing at the same time. The counterweight hammer has a large mass and a large inertia. The initial torque required for the valve disc to overcome the inertia of the counterweight hammer is large. The front edge of the shock wave is not enough to push the valve disc to close completely, thereby extending the response time of the one-way explosion-proof valve.

[0008] There is currently no effective response to factor 2. Manufacturers can only adjust the position of the counterweight on the lever to reduce the resistance torque according to the actual usage of each industry. However, after the position of the counterweight on the lever changes, when there is no wind in the pipeline, the dynamic torque of the valve disc relying on the gravity of the counterweight to reset is reduced, resulting in the valve disc being unable to reset or delayed in reset. Therefore, this method is prone to reset failure.

[0009] In addition, the existing one-way explosion-proof valve counterweight hammer and the corresponding lever are connected by threads. After the one-way explosion-proof valve is installed, the position of the counterweight hammer on the lever needs to be manually adjusted according to the positive wind pressure, so that the wind pressure in the pipeline can push the valve disc to open, and at the same time, the valve disc maintains a certain reset force under the gravity of the counterweight hammer. The method of adjusting the counterweight hammer is: the force of the positive wind pressure pushing the valve disc needs to be greater than the reset force of the valve disc. The smaller the difference between the two forces, the easier it is for the valve disc to open. However, if the force of opening the valve disc is too small, the following two problems will occur:

[0010] 1. The valve disc is too flexible. When the air is supplied at low pressure in the pipeline, the valve disc swings forward and backward in the valve body, the air supply is unstable, and the air outlet has strong and weak winds.

[0011] 2. To solve the above problem 1, we can only readjust the position of the counterweight to increase the force required to open the valve disc. However, when air is supplied at low pressure, the valve disc cannot be fully opened and the wind resistance is large.

[0012] Therefore, the existing one-way explosion-proof valve is fully adapted to the low-pressure pipeline and has the above technical difficulties, while the manual counterweight hammer needs to be operated by professional technicians, and the above problems still exist after adjustment. In general, the pipeline maintains a constant air supply. If the wind pressure changes, the position of the counterweight hammer should be manually adjusted again. Especially after the wind pressure decreases, if the position of the counterweight hammer is not adjusted, the valve disc cannot be opened or the opening angle is small, and the wind resistance is too large. However, the counterweight hammer needs to be adjusted on-site by professional technicians, and frequent adjustments have high labor costs. Summary of the invention

[0013] In view of the deficiencies in the prior art, the present invention aims to provide a low-resistance one-way flap type explosion-proof valve, comprising a valve body, a valve disc, a lever and a counterweight hammer; the two ends of the valve body are respectively provided with an air inlet and an air outlet, the valve disc is hinged in the valve body through a rotating shaft, the middle part of the lever is fixedly connected to one end of the rotating shaft and the lever is located outside the valve body; the counterweight hammer is connected to the upper end of the lever, and the lever is driven to swing by the counterweight hammer, thereby closing the valve disc between the air inlet and the air outlet; it also includes an instant start mechanism, the instant start mechanism includes an explosion-proof telescopic tube, a gas generator and a driving arm; the driving arm is fixed to the other end of the rotating shaft and the driving arm is located outside the valve body, and the outer surface of the valve body is provided with The valve body is fixed with a baffle, and both ends of the explosion-proof telescopic tube are sealed and connected to the driving arm and the baffle respectively, and the gas generator is installed in the explosion-proof telescopic tube, and the driving arm is pushed to swing by the gas generated by the triggering gas generator, so that the rotating shaft drives the valve disc to reset; it also includes an angle monitoring mechanism, and the angle monitoring mechanism includes an angle displacement sensor, a coupling and a bracket; the angle displacement sensor is installed on the outside of the valve body through the bracket, and the input shaft of the angle displacement sensor is opposite to one end of the rotating shaft, and the input shaft and the rotating shaft are coaxially connected through the coupling; it also includes a controller, the input end of the controller is electrically connected to the angle displacement sensor, and the output end of the controller is electrically connected to the gas generator.

[0014] The beneficial effects of the low-resistance one-way flap type explosion-proof valve of the present invention are:

[0015] If an explosion occurs at the lower source of the air supply pipe, material pipe or other pipelines connected to the valve body, the shock wave will cause the valve disc to swing, whether it swings up or down, which can be monitored by the angle displacement sensor. After receiving the electrical signal of the angle change, the controller immediately sends a start electrical signal to the instantaneous start mechanism. The gas generator can quickly inflate the explosion-proof telescopic tube and push the drive arm in 10-15 milliseconds. The drive arm is linked with the shaft and the valve disc, and the valve disc is instantly reset and closed. Compared with the existing valve disc, the instantaneous start mechanism has the following advantages:

[0016] 1. It overcomes the problem that the valve disc position is too high, which causes the valve disc to close late or cannot be reset.

[0017] 2. The response time of the instantaneous start mechanism is shorter than that of the existing flap-type explosion-proof valve, and is not limited by the valve disc opening angle, which shortens the valve disc response time, improves safety performance, and overcomes the problem that the safety factor is inversely proportional to the ventilation performance.

[0018] 3. The gas generated by the gas generator can instantly inflate the explosion-proof telescopic tube, keep the fixed baffle stationary, and use the reaction force to push the driving arm. Since the thrust generated by the inflation of the explosion-proof telescopic tube is very large, the inertia of the counterweight hammer has a very small effect on the rotation of the rotating shaft and can be ignored. This overcomes the problem of delayed valve flap closing caused by the inertia of the counterweight hammer, as well as the problem that the position of the counterweight hammer, the valve flap reset force and the valve flap response time are difficult to adjust.

[0019] Preferably, it also includes a screw linear motor; the lower end of the threaded rod of the screw linear motor is fixed to the middle of the lever, and the threaded rod is parallel to the upper part of the lever; the counterweight is slidably connected to the upper part of the lever, the first stepper motor of the screw linear motor is fixedly connected to the counterweight, and the counterweight is provided with a through hole corresponding to the screw, and the first stepper motor is rotated forward and reversely, so that the first stepper motor drives the counterweight to rise and fall along the upper part of the lever; the first stepper motor is electrically connected to the output end of the controller. The upper part of the lever is provided with an axially extending limit convex strip, and the counterweight is provided with a slide groove adapted to the limit convex strip, and the limit convex strip is adapted to the slide groove, so as to prevent the counterweight from rotating. The first stepper motor can be controlled to rotate forward by the controller, and due to the limitation of the limit convex strip and the slide groove, the first stepper motor and the counterweight can only rise synchronously and cannot rotate. On the contrary, the first stepper motor and the counterweight can only descend synchronously and cannot rotate. Compared with the existing manual adjustment method of the counterweight hammer, the controller adopts a PLC control machine, which can design the corresponding automatic adjustment program according to the wind pressure, and adjust the valve disc opening angle and the valve disc reset force accordingly according to the angle change feedback from the angle monitoring mechanism. It has a high degree of automation, is suitable for frequent adjustments, and has low labor costs.

[0020] Preferably, it also includes a locking mechanism, which includes a U-shaped card and a spring pin; the U-shaped card is fixed to the outside of the valve body, and the opening of the U-shaped card faces the direction of the lower part of the lever; the spring pin is installed on the U-shaped card, and the oblique tongue of the spring pin extends to the opening of the U-shaped card, and is reset through the valve disc, so that the lower part of the lever pushes open the oblique tongue and swings to the opening of the U-shaped card to be reset and locked by the spring pin. A large torque is generated at the moment of explosion of the instantaneous start mechanism, and the lower part of the lever quickly swings to the opening of the U-shaped card under the action of the torque, and the spring pin is reset and locked, which can avoid rebound caused by collision between the lever and the U-shaped card, that is, avoid the valve disc from opening again due to the reaction force of the collision.

[0021] Preferably, it also includes an angle control mechanism, which includes a second stepper motor, a first gear and a second gear; the first gear is coaxially fixed to one end of the rotating shaft, and the second gear is coaxially fixed to the output shaft of the second motor; the second stepper motor is connected to the outside of the valve body, and the first gear is meshed with the second gear; the second stepper motor is electrically connected to the output end of the controller. The output shaft of the second stepper motor can generate torsional resistance when powered, or generate torsional resistance by relying on the rotor magnetic resistance when not powered. The torsional resistance here can make the valve flap swing to a specified angle and then hover, making up for the problem that the valve flap is not opened at an adequate angle due to low wind pressure and the large wind resistance of the valve body.

[0022] Preferably, the angle control mechanism further includes a telescopic motor and a slide rail assembly; the base of the slide rail assembly is fixed to the outside of the valve body, and the slider of the slide rail assembly is fixedly connected to the cylinder of the telescopic motor; the cylinder of the telescopic motor is coaxial and fixedly connected to the housing of the second stepper motor, and the telescopic rod of the telescopic motor is fixedly connected to the limit plate outside the valve body, and the second stepper motor is driven by the telescopic motor to move along the sliding direction of the slide rail assembly, thereby causing the first gear and the second gear to mesh or separate. If the wind pressure is large enough, the valve flap can be pushed to open to the maximum angle. In this case, the telescopic motor retracts and the first gear and the second gear separate. If the wind pressure is insufficient, the valve flap is not opened enough and the wind resistance of the valve flap is large. In this case, the telescopic motor extends, the first gear and the second gear mesh, and the second stepper motor drives the valve flap to rotate to a suitable opening. The telescopic motor of the angle control mechanism intervenes or does not intervene in the control of the valve flap according to these two situations.

[0023] Preferably, the first gear includes a plurality of arc gears, all of which are spliced ​​in sequence along the circumferential direction to form a circular first gear, and each two adjacent arc gears are spliced ​​and connected by at most two pins. Since the second stepper motor intervenes in the valve flap angle control, if a pipeline source explosion occurs, the rotational resistance of the second stepper motor will affect the response time of the valve flap closing. Therefore, a detachable first gear structure is adopted, and the large torque produced by the instantaneous start mechanism is used to instantly destroy the transmission relationship between the rotating shaft, the first gear, the second gear and the second stepper motor, thereby avoiding the influence of the rotational resistance of the second stepper motor on the valve flap reset.

[0024] Preferably, the air inlet and the air outlet are respectively provided with flanges for connection.

[0025] The present invention also provides a control method for a low-resistance one-way flap type explosion-proof valve, which is applied to the above-mentioned low-resistance one-way flap type explosion-proof valve, and a limit rod for controlling the maximum opening angle of the valve disc is arranged inside the valve body, and the steps are as follows:

[0026] S1. The blower starts, forming a positive constant wind pressure in the pipe. The positive wind pressure pushes the valve disc to the maximum angle. At the same time, the shaft drives the drive arm and the angle displacement sensor to rotate. The drive arm swings and compresses the explosion-proof telescopic tube.

[0027] S2. Two minutes after the valve disc is opened, the angle displacement sensor captures angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An. A1, A2, A3...An are fed back to the controller.

[0028] S3. The controller takes A1 as the reference value and compares the deviation between A1 and A2;

[0029] S4. If the deviation exceeds 2%, the controller determines that the shock wave or reverse airflow from the source below the valve disc pushes the valve disc to swing, and the controller triggers the gas generator. Within 10-15 milliseconds, the gas in the explosion-proof telescopic tube pushes the drive arm to swing in the opposite direction, and the lower part of the lever swings to the opening of the U-shaped card. The oblique tongue is pushed open and reset, the lever is locked, and the valve disc is closed;

[0030] S5. If the deviation does not exceed 2%, the controller continues to compare the deviation between A1 and A2, the deviation between A1 and A3, and the deviation between A1 and An until the deviation exceeds 2%, or the deviation never exceeds 2%, and the controller does not trigger the gas generator;

[0031] The controller comparison in S6.S5 is completed, the blower stops, and the valve disc is reset under the gravity of the counterweight hammer.

[0032] The beneficial effect of the control method of a low-resistance one-way flap type explosion-proof valve provided by the present invention is that: when the positive wind pressure in the pipeline is sufficient to open the valve disc to the maximum angle, a limit rod is set to limit the maximum opening angle, but the maximum opening angle here is 10-20% larger than the maximum opening angle of the existing isolation valve, which makes up for the problem of limited maximum opening of the valve disc and large wind resistance due to safety factor limitation of the existing isolation valve.

[0033] The present invention also provides another control method for a low-resistance one-way flap type explosion-proof valve, which is applied to the above-mentioned low-resistance one-way flap type explosion-proof valve, and the steps are as follows:

[0034] S1. The controller sets the maximum opening angle of the valve disc;

[0035] S2. The controller causes the telescopic motor to drive the second stepping motor to move along the base, so that the first gear and the second gear are separated;

[0036] S3. The blower starts, forming a positive constant wind pressure in the pipe. The positive wind pressure pushes the valve disc to open, but the valve disc has not reached the maximum angle. At the same time, the shaft drives the drive arm and the angle displacement sensor to rotate, and the drive arm swings and compresses the explosion-proof telescopic tube;

[0037] S4. The controller causes the first stepper motor to drive the counterweight hammer to descend, so that the valve flap opening angle increases, but the valve flap does not reach the maximum angle, thereby reducing the wind resistance of the valve body;

[0038] S5. One minute after the valve disc is opened, the angle displacement sensor captures the angle data and feeds it back to the controller;

[0039] S6. The controller causes the telescopic motor to drive the second stepping motor to reset, and the first gear and the second gear are meshed;

[0040] S7. The controller operates the second stepper motor, drives the first gear to rotate through the second gear, and the rotating shaft drives the valve disc to swing until the valve disc reaches the maximum opening angle, and the second stepper motor stops rotating. The resistance of the output shaft of the second stepper motor maintains the current angle of the valve disc, thereby further reducing the wind resistance of the valve body;

[0041] S8. Three minutes after the valve disc is opened, the angle displacement sensor captures angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An, and A1, A2, A3...An are fed back to the controller;

[0042] S9. The controller takes A1 as a reference value and compares the deviation between A1 and A2;

[0043] S10. If the deviation exceeds 2%, the controller determines that the shock wave or reverse airflow from the source below the valve disc pushes the valve disc to swing, and the controller triggers the gas generator. Within 10-15 milliseconds, the gas in the explosion-proof telescopic tube pushes the drive arm to swing in the opposite direction, the latch of the first gear breaks and disintegrates, the lower part of the lever swings to the opening of the U-shaped card, the oblique tongue is pushed open and reset, the lever is locked, and the valve disc is closed;

[0044] S11. If the deviation does not exceed 2%, the controller continues to compare the deviation between A1 and A2, the deviation between A1 and A3, ... the deviation between A1 and An, until the deviation exceeds 2%, or the deviation never exceeds 2%, the controller does not trigger the gas generator;

[0045] The controller comparison in S12.S11 is completed, the blower stops, and the controller causes the first stepper motor to drive the counterweight hammer to reset, and the valve disc resets under the gravity of the counterweight hammer.

[0046] Another control method of a low-resistance one-way flap type explosion-proof valve provided by the present invention has the beneficial effect that: when the positive wind pressure in the pipeline is insufficient to open the valve disc to the maximum angle, the second stepper motor drives the valve disc to swing to the maximum angle, which makes up for the problem of insufficient valve disc opening angle and excessive wind resistance under low wind pressure. In addition, the rotational resistance of the second stepper motor is used to overcome the problem of the valve disc swinging forward and backward in the valve body, unstable air supply, and strong and weak wind at the air outlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 The structure of the low-resistance one-way flap type explosion-proof valve in the first embodiment is shown in FIG. Figure 1 ;

[0049] Figure 2 The structure of the low-resistance one-way flap type explosion-proof valve in the first embodiment is shown in FIG. Figure 2 ;

[0050] Figure 3 This is a schematic diagram of the internal structure of the low-resistance one-way flap type explosion-proof valve in Example 1;

[0051] Figure 4 The structure of the low-resistance one-way flap type explosion-proof valve in the second embodiment is shown in FIG. Figure 1 ;

[0052] Figure 5 The structure of the low-resistance one-way flap type explosion-proof valve in the second embodiment is shown in FIG. Figure 2 ;

[0053] Figure 6 This is a schematic diagram of the internal structure of the low-resistance one-way flap type explosion-proof valve in the second embodiment;

[0054] Figure 7 The structure of the first gear in the second embodiment is shown in FIG. Figure 1 ;

[0055] Figure 8 The structure of the first gear in the second embodiment is shown in FIG. Figure 2 .

[0056] 1. Valve body; 2. Valve disc; 3. Lever; 4. Counterweight; 5. Air inlet; 6. Air outlet; 7. Flange; 8. Rotating shaft; 9. Extension tube; 10. Reinforcement rib; 11. Bushing; 12. U-shaped card; 13. Spring pin; 14. Oblique tongue; 15. Threaded rod; 16. First stepper motor; 17. Through hole; 18. Limiting convex strip; 19. Slide groove; 20. Explosion-proof telescopic tube; 21. Gas generator; 22. Driving arm; 23. Fixed baffle; 24. Angle displacement sensor; 25. Coupling; 26. Bracket; 27. Latch; 28. Limiting rod; 29. ​​Second stepper motor; 30. First gear; 31. Second gear; 32. Telescopic motor; 33. Slide rail assembly; 34. Base; 35. Sliding block; 36. Limiting plate; 37. Arc gear. DETAILED DESCRIPTION

[0057] In view of the deficiencies in the prior art, the inventor of this case has proposed the technical solution of the present invention after long-term research and extensive practice. The following will further explain the technical solution, its implementation process and principle, etc. in conjunction with the drawings in the embodiments of this application and specific implementation cases.

[0058] It should be noted that the embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, the present invention covers any substitution, modification, equivalent method and scheme made on the spirit, principle and scope of the present invention defined by the claims. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] In the description of the present application, "first", "second", "third" and similar words do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, "one" or "an" and other similar words do not indicate a quantity limitation, but indicate the existence of at least one. "Include" or "comprise" and other similar words mean that the elements or objects appearing before "include" or "comprises" include the elements or objects listed after "include" or "comprises" and their equivalents, and do not exclude other elements or objects. "Connect" or "connected" and other similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0060] In the description of the present application, the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, when positional terms such as both sides, outside, up and down are used, it should be understood that they are only used to facilitate understanding and description, considering that the structure may be facing other positions. Example

[0061] Embodiment 1 provides a low-resistance one-way flap type explosion-proof valve, comprising a valve body 1, a valve disc 2, a lever 3 and a counterweight 4; the two ends of the valve body 1 are respectively provided with an air inlet 5 and an air outlet 6. In order to meet the pipeline installation requirements, the air inlet 5 and the air outlet 6 are respectively provided with flanges 7 for connection, and the specific model of the flange 7 is selected according to the pipeline model. The valve disc 2 is hinged in the valve body 1 through a rotating shaft 8. Specifically, the air inlet 5 of the valve body 1 extends inward along the axial direction of the valve body 1 and forms an extension tube 9. The end face of the extension tube 9 facing inward is an upward inclined section, and the valve disc 2 is covered on the section to form a seal. In order to improve the sealing performance, a sealing ring is usually added to the section, or a sealing gasket is added to the side of the valve disc 2 opposite to the section. A reinforcing rib 10 is provided in the middle of the valve disc 2, and the reinforcing rib 10 is fixedly connected to the rotating shaft 8. The valve disc 2 is driven by the rotating shaft 8 to cover the incision to seal the valve body 1, or to separate from the incision to open the valve body 1.

[0062] The middle part of the lever 3 in this embodiment is fixedly connected to one end of the rotating shaft 8 through a sleeve 11, and the lever 3 is located outside the valve body 1. The sleeve 11 is provided with a top screw for tightening the rotating shaft 8. The lower part of the lever 3 is provided with an adaptive locking mechanism. The locking mechanism includes a U-shaped card 12 and a spring pin 13; the U-shaped card 12 is fixed to the outside of the valve body 1, and the opening of the U-shaped card 12 faces the direction where the lower part of the lever 3 is located; the spring pin 13 is installed on the U-shaped card 12, and the oblique tongue 14 of the spring pin 13 extends to the opening of the U-shaped card 12, and is reset through the valve disc 2, so that the lower part of the lever 3 pushes open the oblique tongue 14 and swings to the opening of the U-shaped card 12 to be reset and locked by the spring pin 13.

[0063] Although the counterweight 4 in this embodiment is connected to the upper end of the lever 3, the counterweight 4 drives the lever 3 to swing, thereby closing the valve flap 2 between the air inlet 5 and the air outlet 6. However, the connection method between the counterweight 4 and the lever 3 is different from the existing threaded connection method, but adopts a sliding connection, specifically, a sliding connection is formed by a screw linear motor. The lower end of the threaded rod 15 of the screw linear motor here is fixed to the middle of the lever 3, and the threaded rod 15 is parallel to the upper part of the lever 3; the counterweight 4 is slidably connected to the upper part of the lever 3, the first stepper motor 16 of the screw linear motor is fixedly connected to the counterweight 4, and the counterweight 4 is provided with a through hole 17 corresponding to the screw, and the first stepper motor 16 is rotated forward and reversely, thereby driving the counterweight 4 to rise and fall along the upper part of the lever 3; the first stepper motor 16 is electrically connected to the output end of the controller. The upper part of the lever 3 is provided with an axially extending limit convex strip 18, and the counterweight hammer 4 is provided with a slide groove 19 adapted to the limit convex strip 18. The limit convex strip 18 is adapted to the slide groove 19, thereby preventing the counterweight hammer 4 from rotating. The first stepper motor 16 can be controlled to rotate forward by the controller. Due to the restrictions of the limit convex strip 18 and the slide groove 19, the first stepper motor 16 and the counterweight hammer 4 can only rise synchronously and cannot rotate. On the contrary, the first stepper motor 16 and the counterweight hammer 4 can only descend synchronously and cannot rotate. Compared with the existing manual adjustment method of the counterweight hammer 4, the controller adopts a PLC control machine, which can design a corresponding automatic adjustment program according to the wind pressure, and adjust the opening angle of the valve flap 2 and the reset force of the valve flap 2 according to the angle change fed back by the angle monitoring mechanism. It has a high degree of automation and can be applied to frequent adjustments, with low labor costs.

[0064] In order to improve the response speed of the valve flap 2, the instantaneous start mechanism is used in this embodiment to quickly respond to the shock wave or reverse airflow generated by the explosion. The specific structure of the instantaneous start mechanism includes an explosion-proof telescopic tube 20, a gas generator 21 and a driving arm 22; the driving arm 22 is fixed to the other end of the rotating shaft 8 by another shaft sleeve 11 and the driving arm 22 is located outside the valve body 1, and a fixed baffle 23 is provided on the outer surface of the valve body 1. The two ends of the explosion-proof telescopic tube 20 are respectively sealed and connected to the driving arm 22 and the baffle, and the gas generator 21 is installed in the explosion-proof telescopic tube 20. The gas generated by the triggering gas generator 21 drives the driving arm 22 to swing, thereby causing the rotating shaft 8 to drive the valve flap 2 to reset. It also includes an angle monitoring mechanism, which includes an angle displacement sensor 24, a coupling 25 and a bracket 26; the angle displacement sensor 24 is installed on the outside of the valve body 1 through the bracket 26, and the input shaft of the angle displacement sensor 24 is directly opposite to one end of the rotating shaft 8, and the input shaft and the rotating shaft 8 are coaxially connected through the coupling 25; it also includes a controller, the input end of the controller is electrically connected to the angle displacement sensor 24, and the output end of the controller is electrically connected to the gas generator 21.

[0065] In view of the response speed of the valve disc 2, the present embodiment also provides a control method for a low-resistance one-way flap type explosion-proof valve, which is applied to the above-mentioned low-resistance one-way flap type explosion-proof valve. The valve body 1 in the present embodiment is the same as the existing valve body 1 in that a limit rod 28 for controlling the maximum opening angle of the valve disc 2 is arranged inside the valve body 1. However, the difference is that the limit rod 28 in the present embodiment is 10-20% shorter than the existing limit rod 28, so the maximum opening angle of the valve disc 2 is larger than the existing valve disc 2. At the same time, in order to meet the safety factor requirements, that is, the response speed must meet the industry requirements, especially the explosion-proof valve response speed specified by the flammable and explosive industry. This embodiment meets this through the following control method:

[0066] Under normal circumstances, when the blower is started, the material or air forms a positive constant wind pressure in the pipeline, and the positive wind pressure pushes the valve flap 2 to the maximum angle, that is, the valve flap 2 swings upward and touches the limit rod 28. At the same time, the shaft 8 drives the driving arm 22 and the angle displacement sensor 24 to rotate, and the driving arm 22 swings and compresses the explosion-proof telescopic tube 20.

[0067] Two minutes after the valve flap 2 is opened, the wind pressure in the pipeline is stable and does not change, that is, under a sufficiently large positive wind pressure, the valve flap 2 is always supported by the limit rod 28 and does not shake. The angle displacement sensor 24 captures angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An, and A1, A2, A3...An are fed back to the controller. As long as the blower is in operation, the angle displacement sensor 24 keeps collecting angle data and provides real-time feedback on whether the valve flap 2 is swinging.

[0068] Then, the controller takes A1 as a reference value, and compares the deviations between A1 and A2, A1 and A3, A1 and A4, ... A1 and An.

[0069] If the deviation of a comparison exceeds 2% at a certain time, the controller determines that the shock wave or reverse airflow from the source below the valve flap 2 pushes the valve flap 2 to swing. Under normal air supply conditions, the wind pressure in the pipeline is constant and the valve flap 2 will not swing. Once it swings, it means that the air pressure in the source pipeline has changed, or the shock wave has moved up along the pipeline. At this time, the controller triggers the gas generator 21, and within 10-15 milliseconds, the gas in the explosion-proof telescopic tube 20 pushes the drive arm 22 to swing in the opposite direction, and the lower part of the lever 3 swings to the opening of the U-shaped card 12. The inclined tongue 14 is pushed open and reset, the lever 3 is locked, and the valve flap 2 is closed. On the contrary, if the deviation does not exceed 2%, the controller does not trigger the gas generator 21 until the blower stops, the angle displacement sensor 24 is no longer monitored, and the valve flap 2 is reset under the gravity of the counterweight hammer 4.

[0070] It can be seen from the above method that when the positive wind pressure in the pipeline is sufficient to open the valve flap 2 to the maximum angle, the real-time monitoring of the valve flap 2 by the angle displacement sensor 24 does not affect the swing of the valve flap 2. The purpose of the maximum opening angle of the valve flap 2 being larger than that of the existing valve flap 2 is to reduce wind resistance and improve ventilation effect. The gas generated by the gas generator 21 can instantly inflate the explosion-proof telescopic tube 20, the fixed baffle 23 remains stationary, and then the reaction force is used to push the driving arm 22. Since the thrust generated by the inflation of the explosion-proof telescopic tube 20 is very large, the inertia of the counterweight hammer 4 has little effect on the rotation of the rotating shaft 8 and can be ignored, thus overcoming the problem of delayed closing of the valve flap 2 due to the inertia of the counterweight hammer 4, and the problem of difficulty in adjusting the position of the counterweight hammer 4, the reset force of the valve flap 2 and the corresponding time of the valve flap 2. At the same time, it also overcomes the problem of delayed closing of the valve flap 2 or failure to reset due to the high or too high position of the valve flap 2. Example

[0071] Embodiment 2 provides another low-resistance one-way flap type explosion-proof valve. The low-resistance one-way flap type explosion-proof valve of Embodiment 2 has the same structure as the low-resistance one-way flap type explosion-proof valve of Embodiment 1, except for the following two points:

[0072] First point: there is no limit rod 28 in the valve body 1 .

[0073] Second point: An angle control mechanism is added. The specific structure of the angle control mechanism is as follows:

[0074] The angle control mechanism includes a second stepper motor 29, a first gear 30 and a second gear 31; the first gear 30 is coaxially fixed to one end of the rotating shaft 8, and the second gear 31 is coaxially fixed to the output shaft of the second motor; the second stepper motor 29 is connected to the outside of the valve body 1, and the first gear 30 is meshed with the second gear 31; the second stepper motor 29 is electrically connected to the output end of the controller. The output shaft of the second stepper motor 29 can generate torsional resistance when powered, or generate torsional resistance by relying on the rotor magnetic resistance when not powered. The torsional resistance here can make the valve flap 2 swing to a specified angle and then hover, making up for the problem that the valve flap 2 is not opened at an angle due to low wind pressure and the valve body 1 has a large wind resistance. The angle control mechanism also includes a telescopic motor 32 and a slide rail assembly 33; the base 34 of the slide rail assembly 33 is fixed to the outside of the valve body 1, and the slider 35 of the slide rail assembly 33 is fixedly connected to the cylinder of the telescopic motor 32; the cylinder of the telescopic motor 32 is coaxial and fixedly connected to the housing of the second stepper motor 29, and the telescopic rod of the telescopic motor 32 is fixedly connected to the limit plate 36 outside the valve body 1. The telescopic motor 32 drives the second stepper motor 29 to move along the sliding direction of the slide rail assembly 33, thereby engaging or disengaging the first gear 30 and the second gear 31. The wind pressure is large enough to push the valve flap 2 to open to the maximum angle. In this case, the telescopic motor 32 retracts and the first gear 30 and the second gear 31 are separated. The wind pressure is insufficient, the valve flap 2 is not opened enough, and the wind resistance of the valve flap 2 is large. In this case, the telescopic motor 32 extends, the first gear 30 and the second gear 31 engage, and the second stepper motor 29 drives the valve flap 2 to rotate to a suitable opening. The telescopic motor 32 of the angle control mechanism intervenes or does not intervene in the control of the valve flap 2 according to these two situations.

[0075] Compared with the low-resistance one-way flap type explosion-proof valve in Example 1, the low-resistance one-way flap type explosion-proof valve in this embodiment is mainly suitable for use scenarios with lower forward wind pressure in the pipeline. At the same time, it is necessary to overcome the problems of small opening of the valve flap 2, large wind resistance, and discontinuous and uneven air outlet caused by the back and forth swinging of the valve flap 2.

[0076] This embodiment adopts the following control method to solve the above problems:

[0077] First, the controller causes the telescopic motor 32 to drive the second stepper motor 29 to move along the base 34, so that the first gear 30 and the second gear 31 are separated. The blower is started, and a positive constant wind pressure is formed in the pipeline. The positive wind pressure pushes the valve flap 2 to open, but the valve flap 2 does not reach the maximum angle. At the same time, the shaft 8 drives the driving arm 22 and the angle displacement sensor 24 to rotate, and the driving arm 22 swings and compresses the explosion-proof telescopic tube 20;

[0078] Then, for the positive low wind pressure, the controller causes the first stepper motor 16 to drive the counterweight 4 to descend, reducing the resistance arm of the counterweight 4, so that the opening angle of the valve flap 2 increases. However, the valve flap 2 cannot reach the maximum angle by adjusting the position of the counterweight 4 alone, or the valve flap 2 is too sensitive and swings back and forth by adjusting the position of the counterweight 4 alone. In both cases, after the valve flap 2 is opened for one minute, the angle displacement sensor 24 captures the angle data once and feeds it back to the controller.

[0079] Then, the controller enables the telescopic motor 32 to drive the second stepper motor 29 to reset, and the first gear 30 and the second gear 31 are meshed. The controller enables the second stepper motor 29 to work, and drives the first gear 30 to rotate through the second gear 31, and the shaft 8 drives the valve flap 2 to swing until the valve flap 2 reaches the maximum opening angle, and the second stepper motor 29 stops, and the resistance of the output shaft of the second stepper motor 29 maintains the current angle of the valve flap 2, thereby further reducing the wind resistance of the valve body 1. Three minutes after the valve flap 2 is opened, the angle displacement sensor 24 captures the angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An, and A1, A2, A3...An are fed back to the controller;

[0080] Finally, the controller uses A1 as the reference value and compares the deviation between A1 and A2.

[0081] If the deviation exceeds 2%, the controller determines that the shock wave or reverse airflow from the source under the valve flap 2 pushes the valve flap 2 to swing, and the controller triggers the gas generator 21. Within 10-15 milliseconds, the gas in the explosion-proof telescopic tube 20 pushes the driving arm 22 to swing in the opposite direction, the latch 27 of the first gear 30 breaks and disintegrates, the lower part of the lever 3 swings to the opening of the U-shaped card 12, the inclined tongue 14 is pushed open and reset, the lever 3 is locked, and the valve flap 2 is closed. In order to make the first gear 30 disintegrate under a large torque and be able to be spliced ​​and reused, the first gear 30 in this embodiment includes a plurality of arc gears 37, all of which are spliced ​​in sequence along the circumference to form a circular first gear 30, and each adjacent two arc gears 37 are spliced ​​and connected by at most two latches 27. The latch 27 here is made of fragile wood material, plastic material or glass material. Driven by the torque of the second stepping motor 29, the latch 27 itself has a certain strength, and the first gear 30 does not disintegrate. However, if the torque suddenly increases several times or dozens of times, the latch 27 is damaged, and the first gear 30 disintegrates. Since the second stepper motor 29 intervenes in the angle control of the valve flap 2, if an explosion occurs in the pipeline, the rotation resistance of the second stepper motor 29 will affect the response time of the valve flap 2 closing. Therefore, a detachable first gear 30 structure is adopted, and the large torque produced by the instantaneous start mechanism is used to instantly destroy the transmission relationship between the rotating shaft 8, the first gear 30, the second gear 31 and the second stepper motor 29, thereby avoiding the influence of the rotation resistance of the second stepper motor 29 on the reset of the valve flap 2.

[0082] If the deviation does not exceed 2%, the controller continues to compare the deviation between A1 and A2, the deviation between A1 and A3, and the deviation between A1 and An, until the deviation exceeds 2%, or the deviation never exceeds 2%, and the controller does not trigger the gas generator 21. After the comparison is finished, the blower stops, and the controller causes the first stepper motor 16 to drive the counterweight 4 to reset, and the valve flap 2 is reset under the gravity of the counterweight 4.

[0083] In this embodiment, when the positive wind pressure in the pipeline is insufficient to open the valve flap 2 to the maximum angle, the second stepper motor 29 drives the valve flap 2 to swing to the maximum angle, which makes up for the problem of insufficient opening angle of the valve flap 2 and excessive wind resistance under low wind pressure. In addition, the rotation resistance of the second stepper motor 29 is used to overcome the problem of the valve flap 2 swinging forward and backward in the valve body 1, the air supply is not stable, and the air outlet 6 has strong and weak wind.

[0084] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly. It cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, some simple deductions or substitutions can be made without departing from the concept of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A low-resistance one-way flap type explosion-proof valve, comprising a valve body, a valve disc, a lever and a counterweight hammer; the two ends of the valve body are respectively provided with an air inlet and an air outlet, the valve disc is hinged in the valve body through a rotating shaft, the middle part of the lever is fixedly connected to one end of the rotating shaft and the lever is located outside the valve body; the counterweight hammer is connected to the upper end of the lever, and the lever is driven to swing by the counterweight hammer, so that the valve disc is closed between the air inlet and the air outlet; Features: It also includes an instant-start mechanism, which includes an explosion-proof telescopic tube, a gas generator and a driving arm; the driving arm is fixed to the other end of the rotating shaft and is located outside the valve body, and a fixed baffle is provided on the outer surface of the valve body. The two ends of the explosion-proof telescopic tube are respectively sealed and connected to the driving arm and the baffle, and the gas generator is installed in the explosion-proof telescopic tube. The driving arm is pushed to swing by the gas generated by the triggering gas generator, so that the rotating shaft drives the valve disc to reset; It also includes an angle monitoring mechanism, which includes an angle displacement sensor, a coupling and a bracket; the angle displacement sensor is installed on the outside of the valve body through the bracket, and the input shaft of the angle displacement sensor is directly opposite to one end of the rotating shaft, and the input shaft and the rotating shaft are coaxially connected through the coupling; Also includes a controller, the input end of the controller is electrically connected to the angle displacement sensor, and the output end of the controller is electrically connected to the gas generator; It also includes a screw linear motor; the lower end of the threaded rod of the screw linear motor is fixed to the middle of the lever, and the threaded rod is parallel to the upper part of the lever; the counterweight is slidably connected to the upper part of the lever, the first stepper motor of the screw linear motor is fixedly connected to the counterweight, and the counterweight is provided with a through hole corresponding to the screw, and the first stepper motor is rotated forward and reversely, so that the first stepper motor drives the counterweight to rise and fall along the upper part of the lever; the first stepper motor is electrically connected to the output end of the controller; It also includes a locking mechanism, which includes a U-shaped card and a spring pin; the U-shaped card is fixed to the outside of the valve body, and the opening of the U-shaped card faces the direction where the lower part of the lever is located; the spring pin is installed on the U-shaped card, and the oblique tongue of the spring pin extends to the opening of the U-shaped card, and is reset through the valve disc, so that the lower part of the lever pushes the oblique tongue open and swings to the opening of the U-shaped card to be reset and locked by the spring pin; It also includes an angle control mechanism, which includes a second stepper motor, a first gear and a second gear; the first gear is coaxially fixed to one end of the rotating shaft, and the second gear is coaxially fixed to the output shaft of the second motor; the second stepper motor is connected to the outside of the valve body, and the first gear is meshed with the second gear; the second stepper motor is electrically connected to the output end of the controller; The angle control mechanism also includes a telescopic motor and a slide rail assembly; the base of the slide rail assembly is fixed to the outside of the valve body, and the slider of the slide rail assembly is fixedly connected to the cylinder of the telescopic motor; the cylinder of the telescopic motor is coaxial and fixedly connected to the housing of the second stepper motor, and the telescopic rod of the telescopic motor is fixedly connected to the limit plate outside the valve body. The second stepper motor is driven by the telescopic motor to move along the sliding direction of the slide rail assembly, thereby engaging or disengaging the first gear and the second gear.

2. A low-resistance one-way flap type explosion-proof valve according to claim 1, characterized in that: The upper part of the lever is provided with an axially extending limiting convex strip, and the counterweight hammer is provided with a sliding groove adapted to the limiting convex strip. The limiting convex strip is adapted to the sliding groove, thereby preventing the counterweight hammer from rotating.

3. The low-resistance one-way flap type explosion-proof valve according to claim 1, characterized in that: The first gear includes a plurality of arc gears, all of which are spliced ​​in sequence along the circumferential direction to form a circular first gear, and every two adjacent arc gears are spliced ​​and connected by at most two pins.

4. The low-resistance one-way flap type explosion-proof valve according to claim 1, characterized in that: The air inlet and the air outlet are respectively provided with flanges for connection.

5. A control method for a low-resistance one-way flap type explosion-proof valve, characterized in that: The low-resistance one-way flap type explosion-proof valve according to claim 1 is applied to a limit rod for controlling the maximum opening angle of the valve disc inside the valve body, and the steps are as follows: S1. The blower starts, forming a positive constant wind pressure in the pipe. The positive wind pressure pushes the valve disc to the maximum angle. At the same time, the shaft drives the drive arm and the angle displacement sensor to rotate. The drive arm swings and compresses the explosion-proof telescopic tube. S2. Two minutes after the valve disc is opened, the angle displacement sensor captures angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An. A1, A2, A3...An are fed back to the controller. S3. The controller takes A1 as the reference value and compares the deviation between A1 and A2; S4. If the deviation exceeds 2%, the controller determines that the shock wave or reverse airflow from the source below the valve disc pushes the valve disc to swing, and the controller triggers the gas generator. Within 10-15 milliseconds, the gas in the explosion-proof telescopic tube pushes the drive arm to swing in the opposite direction, and the lower part of the lever swings to the opening of the U-shaped card. The oblique tongue is pushed open and reset, the lever is locked, and the valve disc is closed; S5. If the deviation does not exceed 2%, the controller continues to compare the deviation between A1 and A2, the deviation between A1 and A3, and the deviation between A1 and An until the deviation exceeds 2%, or the deviation never exceeds 2%, and the controller does not trigger the gas generator; The controller comparison in S6.S5 is completed, the blower stops, and the valve disc is reset under the gravity of the counterweight hammer.

6. A control method for a low-resistance one-way flap type explosion-proof valve, characterized in that: The low-resistance one-way flap type explosion-proof valve according to claim 3 is applied in the following steps: S1. The controller sets the maximum opening angle of the valve disc; S2. The controller causes the telescopic motor to drive the second stepping motor to move along the base, so that the first gear and the second gear are separated; S3. The blower starts, forming a positive constant wind pressure in the pipe. The positive wind pressure pushes the valve disc to open, but the valve disc has not reached the maximum angle. At the same time, the shaft drives the drive arm and the angle displacement sensor to rotate, and the drive arm swings and compresses the explosion-proof telescopic tube; S4. The controller causes the first stepper motor to drive the counterweight hammer to descend, so that the valve flap opening angle increases, but the valve flap does not reach the maximum angle, thereby reducing the wind resistance of the valve body; S5. One minute after the valve disc is opened, the angle displacement sensor captures the angle data and feeds it back to the controller; S6. The controller causes the telescopic motor to drive the second stepping motor to reset, and the first gear and the second gear are meshed; S7. The controller operates the second stepper motor, drives the first gear to rotate through the second gear, and the rotating shaft drives the valve disc to swing until the valve disc reaches the maximum opening angle, and the second stepper motor stops rotating. The resistance of the output shaft of the second stepper motor maintains the current angle of the valve disc, thereby further reducing the wind resistance of the valve body; S8. Three minutes after the valve disc is opened, the angle displacement sensor captures angle data in real time. The first captured angle data is A1, and the subsequent captured angle data are A2, A3...An, and A1, A2, A3...An are fed back to the controller; S9. The controller takes A1 as a reference value and compares the deviation between A1 and A2; S10. If the deviation exceeds 2%, the controller determines that the shock wave or reverse airflow from the source below the valve disc pushes the valve disc to swing, and the controller triggers the gas generator. Within 10-15 milliseconds, the gas in the explosion-proof telescopic tube pushes the drive arm to swing in the opposite direction, the latch of the first gear breaks and disintegrates, the lower part of the lever swings to the opening of the U-shaped card, the oblique tongue is pushed open and reset, the lever is locked, and the valve disc is closed; S11. If the deviation does not exceed 2%, the controller continues to compare the deviation between A1 and A2, the deviation between A1 and A3, ... the deviation between A1 and An, until the deviation exceeds 2%, or the deviation never exceeds 2%, the controller does not trigger the gas generator; The controller comparison in S12.S11 is completed, the blower stops, and the controller causes the first stepper motor to drive the counterweight hammer to reset, and the valve disc is reset under the gravity of the counterweight hammer.

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