261results about How to "Avoid accidental opening" patented technology

An embodiment of the invention provides a shifting register unit and a driving method thereof, a grid driving circuit and a display apparatus and relates to the display technology field. A problem that a signal input terminal is in a floating state in a touch control phase for a long time so that a pull-up node potential can not be pulled up to a high level quasi bit can be solved. The shifting register unit comprises a voltage stabilization module, a pull-up control module, a pull-up module, a pull-down control module, a pull-down module and a reset module, wherein the voltage stabilization module outputs a signal of a first control signal terminal to the pull-up control module or pulls down a potential of a signal input terminal to the first control signal terminal; the pull-up control module outputs a signal of a third control signal terminal to a pull-up node; the pull-up module outputs a signal of a first clock signal terminal to a signal output terminal; the pull-down control module outputs a signal of a second clock signal terminal to a pull-down node or pulls down a potential of the pull-down node to a first voltage terminal; the pull-down module pulls down the potentials of the pull-up node and the signal output terminal to a first voltage terminal; and the reset module outputs a signal of a fourth control signal terminal to the pull-up node.

The invention provides an automatic passive fire protection spraying valve, which belongs to the field of automatic fire protection control equipment and is characterized in that a valve body is internally provided with a cylindrical water outlet. A membrane type piston is arranged on the upper end of the water outlet. A return spring is arranged in the middle upper part of an internal sleeve. The upper part of the resetting spring is supported against the inner upper part of a valve cover. The external top part of an external sleeve of a valve core is provided with a compression bar which iscovered by a pressure spring. The compression bar passes through a round hole at the top of the internal sleeve and is connected with an adjusting nut on a hot gathering cover. Due to the delayed action of the pressure spring, a defect that a valve is immediately closed when a memory alloy contracts is avoided and the spraying time is delayed.

The invention discloses a self-aligned silicon carbide metal-oxide-semiconductor field-effect-transistor (MOSFET) device with an optimized P<+> region and a fabrication method of the self-aligned silicon carbide MOSFET device. The self-aligned silicon carbide MOSFET device is formed by connecting a plurality of same cells in parallel, and the cells of the silicon carbide MOSFET device are uniformly arranged. Each cell of the silicon carbide MOSFET device comprises two sources, a grid, a grid oxide layer, two N<+> source regions, two P<+> contact regions, two P pits, an N<-> drift layer, a buffer layer, an N<+> substrate, a drain and an isolation dielectric layer. By optimizing the P<+> region, favorable source ohmic contact is formed, the on resistance is reduced, meanwhile, the source and the P pits are in short connection, parasitic negative-positive-negative (PNP) and a parasitic transistor effect of PiN are prevented, the conduction property and the breakdown property of the device can be compatible, and the device can be used in a high-voltage and high-frequency silicon carbide MOSFET device. A self-aligned fabrication method is adopted by the invention, the process is simplified, the channel size is accurately controlled, and a transverse or longitudinal power MOSFET can be fabricated.

Disclosed is a horizontal well external staged fracturing sand control string and method. A filling service string is tripped in an external staged fracturing and filling sand-control drain string. The external fracturing and filling sand-control drain string comprises a cementing external packer and a filling tool assembly connected in succession. The filling service string comprises a liquid-packing seal, a filling pipe, a filling converter, a flexible pressure tester, a rotary positioning tool, sliding sleeve opening and closing tools, and a packing sealing assembly; the filling pipe, the filling converter, the flexible pressure tester, the rotary positioning tool, the sliding sleeve opening and closing tools and the packing sealing assembly are mounted and connected onto the lower portion of the liquid-packing seal in succession; the lower end of the filling pipe and the lower end of a packing pipe are parallelly connected with the filling converter, and a liquid annulus is arranged between the filling pipe and the packing pipe. The filling tool assembly comprises an upper seal cylinder, a filling pipe external packer, and a filling sliding sleeve; the filling pipe external packer and the filling sliding sleeve are mounted and connected onto the upper seal cylinder in succession. According to the method, an open hole segment is packaged into two to ten parts; the method includes: A, tripping the filling service string in the external staged fracturing sand-control drain string; B, during filling of an upper layer, fitting a bottom packing sealing assembly and the seal cylinder to prevent filling liquid from entering a lower layer; C, repeating the step B to sequentially complete fractured gravel filling sand control for all layers.

The invention discloses an elevator landing door device. The elevator landing door device comprises a landing door device body, a door hanging plate, a door guide rail, a landing door, two fixed hooks, two flexible hooks, two unlocking units and a manual operating part; the first fixed hook and the second fixed hook are fixed on the landing door device body; the second fixed hook is arranged above the first fixed hook; the first flexible hook is arranged on the door hanging plate through a first fixed shaft and can rotate around the first fixed shaft; the first flexible hook is driven by the first unlocking unit to rotate to enable the first flexible hook to be separated from the first fixed hook; the second flexible hook is arranged on the door hanging plate through a second fixed shaft and can rotate around the second fixed shaft; the second flexible hook is driven by the second unlocking unit to rotate to enable the second flexible hook to be separated from the second fixed hook; the first flexible hook rotates in the opposite direction when the second flexible hook rotates; one end of the manual operating part is connected with the second unlocking unit; the other end of the manual operating part is located at the position of the landing door. According to the elevator landing door device, the risk of the accidental opening of the landing door due to the fact that one of locking mechanisms fails can be avoided due to the two locking mechanisms and the shaft falling is prevented through secondary unlocking.

The invention provides a dual-mode synchronous rectification control circuit for a DCM and a CCM, belonging to the technical field of power management. The structure of the circuit is simple, the rectification conduction loss can be effectively reduced, and high efficiency of synchronous rectification is realized. Minimum dead time control is realized by a second negative level detector. A turn-off time shielding module prevents the wrong turn-on of a synchronous rectifier tube M2, and a turn-on time shielding module prevents the wrong turn-off of the synchronous rectifier tube M2. Drain electrodes of LDMOS and DEMOS high voltage devices are used by a first sampling end to bear high voltage, the clamping of a drain end VD of the synchronous rectifier tube M2 by a Zener is avoided, and the current leakage to the ground by the drain end VD of the synchronous rectifier tube M2 is prevented. The high efficiency of synchronous rectification is realized by the above measures together. In addition, a synchronous control module is introduced, and the synchronous rectification in a current continuous mode CCM is realized.

The invention discloses a control system of a solid-liquid dynamic sounding rocket. The control system is composed of a ground test launching control part and a rocket-borne control part. The control system is mainly used for realizing the following three tasks: converting ground power supply of a rocket-borne device to rocket-borne power supply, completing test preparation before launching the solid-liquid dynamic sounding rocket to realize the functions of launching control, security control, and the like, and carrying out variable thrust control on the solid-liquid dynamic sounding rocket and monitoring, collecting and recording the states. The invention provides a solid-liquid dynamic aircraft control system. By utilizing the solid-liquid dynamic aircraft control system, the functions of monitoring, ignition testing, emergency danger eliminating, and the like to the important rocket-borne device can be realized before the rocket is launched, the rocket-borne control part can realize thrust adjustment control according to control requirements after the rocket is started, and liquid propellant main road and side road channel valves are controlled according to the control requirements to clear residual propellant in a channel after the flight mission is finished. Meanwhile, real-time data acquisition and recording on parameters for reflecting working conditions of a solid-liquid rocket engine are carried out by the rocket-borne control part in the entire flight process.

The invention discloses a synchronized rectifier tube control circuit, comprising: a voltage slope detection circuit, a transformer and synchronized rectifier output stage circuit, a logic circuit and a driving circuit wherein the voltage slope detection circuit, the logic circuit, the driving circuit and the transformer and synchronized rectifier output stage circuit are connected in sequence. According to the invention, through the arrangement of the voltage slope detection circuit to detect the slope for the voltage variation of the synchronized rectifier tube's drain electrode, it is possible to accurately tell the cause of the voltage variation at the drain electrode by the closing of the main power tube at the primary side from the cause of the resonance oscillation by the closing of the synchronized rectifier tube so as to avoid the wrong start of the synchronized rectifier tube due to oscillation and to further realize the right start of the synchronized rectifier tube.

The invention discloses a ground emitting control device of a solid-liquid powered aircraft; the ground emitting control device consists of a front end device and a rear end device. The front end device is a ground control box, wherein the output port of the front end device is connected with the solid-liquid powered aircraft; the rear end device comprises a host computer and a remote control box, and the remote control on the solid-powered liquid-powered aircraft is realized. The ground emitting control device of the solid-liquid powered aircraft mainly finishes two functions; the first function is the igniting emitting function which relates to pressure increase of storage boxes, ignition of igniter and opening of liquid-path electromagnetic valve, and the other function is emitting safety ensuring function which relates to high-pressure gas release of high-pressure bottles, pressure release of storage boxes and oxidant discharge of storage boxes. The ground emitting control device solves problems of complicated system, poor portability and high cost of traditional ground emitting control devices, the precise control of igniting emitting timing sequence aiming at the characteristics of solid-powered liquid-powered aircraft is realized, and the programming can be carried out in an on-line manner so as to modify igniting emitting timing sequence simply and conveniently.

The invention provides a method and system for controlling the switching-on threshold value and the switching-off threshold value of a brake vacuum pump. The method comprises an information acquiring step and a threshold value setting step. According to the information acquiring step, at least the current vehicle speed information and brake information are acquired. According to the threshold setting step, the switching-on threshold value and the switching-off threshold value of the vacuum pump are set respectively at least according to the speed of a vehicle and the magnitude of brake signals through the current vehicle speed information and the brake information, and the working time of the vacuum pump is reduced under the premise that the braking safety is guaranteed. According to the method and system, the switching-on threshold value and the switching-off threshold value of the vacuum pump can be set according to the current vehicle speed information and the brake information, so that the various working conditions of the vehicle in the traveling process are fully considered; under the premise that the brake safety is absolutely guaranteed, the working time of the vacuum pump can be reduced to the greatest extent, the probability of breakdowns due to long-time working of the vacuum pump is lowered, and the service life of the vacuum pump is effectively prolonged.

Provided is a valve opening-closing device used for a compound type medium-sized bulk container and a container. The container comprises a base seat and side boards, and a valve is arranged on the bottom of the container. The valve opening-closing device used for the compound type medium-sized bulk container and the container are characterized in that the opening-closing device comprises a handle, a transmission device, a valve opening-closing mechanism and a clutch device, the handle is arranged on the side boards of the container and connected with the transmission device, the transmission device is used to transmit motion acting on the handle to the valve opening-closing mechanism to achieve opening and closing of a valve, and the clutch device is used to enable engagement and disengagement of the transmission device and the valve opening-closing mechanism to be achieved or engagement and disengagement of the valve opening-closing mechanism and the valve to be achieved. In the valve opening-closing device, the operating handle is arranged on an appropriate position of a side surface of the container, and therefore operation such as bending down or squatting on the ground in the process of opening and closing the valve is avoided. The valve opening-closing device used for the compound type medium-sized bulk container and the container are convenient to use, and can prevent opening the valve by accident.

The invention relates to an angular polishing machine with a secondary action opening mechanism and belongs to the technical field of hand-held electric tool. The angular polishing machine comprises a shell, a motor, a transmission mechanism, a working head and a switch mechanism. The angular polishing machine is characterized in that the angular polishing machine is also provided with an error prevention opening mechanism; a button base is arranged on a shell of the error prevention opening mechanism; the inside of the button base is provided with a button switch which consists of a button, a button lever, a second offsetting spring and a limiting convex block on the button lever; a pull rod is provided with a groove moving along the button lever and a limiting hole correspondingly matched with the limiting convex block; when the button switch is in a closed state, the limiting convex block is in the limiting hole and limits the pulling of the pull rod; and when the button is pressed, the limiting convex block runs through the limiting hole so that the switch mechanism can act. In order to open the angular polishing machine, two obvious actions are needed to reliably avoid causing wrong opening by misoperation and improve the safety performance of the angular polishing machine, thus the angular polishing machine can meet the EN60745-2-3 European normal stipulation.

The invention discloses an automatic closed forging forming die, and belongs to the technical field of metal press machining. The die comprises a rigid die base, a floating female die, and automatic die locking devices symmetrically arranged on the two sides of a lower female die base. The two sides of the upper end face of an upper female die base are symmetrically provided with clamping grooves. Each automatic die locking device comprises a swinging lock rod and a power mechanism driving the swinging lock rod to swing. Lock heads clamped to the clamping grooves in a matched mode are arranged on the tops of the swinging lock rods. During combination of an upper female die and a lower female die, the power mechanisms drive the swinging lock rods to swing in the direction close to the upper female die till the lock heads make contact with the clamping grooves to be clamped; During opening of the upper female die and the lower female die, the power mechanisms drive the swinging lock rods to swing in the direction away from the upper female die till the lock heads get away from the clamping grooves to be reset. The die clamping pressure can be increased, and automatic control over locking and unlocking of the upper and lower female dies of a die locking device is achieved.

A lawn mower having a lateral-side discharge outlet in a body housing for discharging mowed lawn has been configured such that a discharge outlet door for closing the lateral-side discharge outlet is held at a closed position only by a spring force, and therefore, there has been a risk of causing fluttering due to a blowing pressure and vibrations generated by the rotation of a mowing blade. An object of the present invention is to avoid fluttering of the discharge outlet door.In order to avoid fluttering, a lock device (20) is disposed at a discharge outlet door (16) for locking it at a closed position. The lock device (20) is unlocked by an unlock operation by the user, so that accidental opening can be prevented. By setting a spring to be weak, the discharge outlet door (16) can be easily opened.

An object of the invention is to measure out precisely the liquid to be poured out and applied, to safely achieve the firm assembly of components and to obtain effective function of displays. An applying stopper (1), which changeovers communication of a measuring chamber (A) formed by rotational operation between a bottle unit (8) and a pouring out mouth (55), is attached to a bottle unit (8). The measuring chamber (A) is structured by parts that cannot be deformed. Inseparable assembling of an attaching unit (2) and a switching unit (4) of the applying stopper (1) is achieved by bending displacement of engagement coupling function parts. An assembling position of the applying stopper (1) with respect to the bottle unit (8) in the circumferential direction is aligned.

The invention relates to the technical field of cups, in particular to a cup with a cover capable of being opened and closed with a single hand. The cup with the cover capable of being opened and closed with the single hand comprises a cup body assembly and a cup cover assembly, wherein the cup cover assembly comprises a cup cover and an inner cover fixedly arranged in the cup cover, the inner cover stretches into the cup body assembly and is in sealing contact with the inner wall of the cup body assembly, a convex rib is arranged on the outer wall of the open end of the cup body assembly, an opening is formed at a position corresponding to the convex rib on the cup cover, lock catches are rotatably fixed on the two sides of the cup cover through rotating shafts, the rotating shafts are located at the middle portions of the lock catches, claws are arranged at the bottom portions of the lock catches, and the claws can penetrate through the opening of the cup cover and are in clamping connection with the lower end surface of the convex rib. By connecting the cup cover assembly and the cup body assembly by using the rotatable lock catches, the opening of the cup cover can be realized by pressing the tops of the lock catches with the single hand only, and the use is facilitated. By arranging safety lock components in the cup cover assembly, the lock catches can be prevented from being mistakenly unlocked.

The invention relates to an electric tool management system. The system comprises a cabinet body and a cabinet door, an electronic lock is arranged on the cabinet body, a placement rack is arranged in the cabinet body, a master control chip is arranged on the cabinet body and provided with a fingerprint collector and an infrared scanner, a weight sensor is disposed in the placement rack, and the master control chip is connected with a PC. The system has the advantages that an identity card or an employee card is scanned through the infrared scanner to collect information of a tool borrowing person, information processing is achieved through the master control chip, the information is sent into the PC to be stored by an administrator; the administrator can read tool borrowing time, the varieties and the number of borrowed tools and the information of the tool borrowing person at first time, quickly read the varieties and the number of tools left in the cabinet body and quickly inform subsequent operators of the varieties of the tools in the cabinet body, intelligent management is achieved, and the frequency of opening and checking the cabinet body is reduced.

The invention provides an intelligent automobile safety air bag system and a control method and relates to the field of automobile safety. The system is characterized by comprising a sensor system, a processor system, a mobile control terminal and an air bag device; the sensor system comprises a horizontal acceleration sensor, a vertical acceleration sensor, a horizontal speed sensor, a vertical speed sensor and a pressure sensor; the processor system comprises a discriminator, a central processing unit and a self-checking unit; and the air bag device comprises a first safety air bag, a second safety air bag, a third safety air bag, a first gas generator, a second gas generator and a third gas generator. The system has the beneficial effects of being safe, reliable, accurate, individual and the like.

The invention discloses a fluff filtering apparatus used for fluff water and capable of reducing the cleaning frequency and efficiently utilizing the water resource. The apparatus comprises a casing, a fixed support is arranged at the top of the casing, a door is arranged on the casing, a cylindrical filter cylinder is arranged in the casing, the periphery of the filter cylinder is a filter screen, and one end of the filter cylinder is connected with a water inlet tube; a temporary storage bin is arranged in the casing below the filter cylinder, a left separation compartment and a right compartment which are mutually independent are arranged in the temporary storage bin, the left separator of the left compartment and the right separator of the right compartment are respectively provided with compartment hole, and the bottoms of the left and right compartments are respectively provided with a water outlet tube; and a cylinder is arranged outside the casing, the piston rod of the cylinder stretches into the temporary storage bin for connecting with a sealing plate, and the sealing plate can alternatively cap the compartment holes on the right separator and the left separator through the stretching or contracting of the piston rod of the cylinder in order to connect the temporary storage bin with the left compartment or the right compartment.

The invention discloses an air sac device for protecting feet of a car passenger. The air sac device comprises an air sac, a sensor, an air generator and an air sac ECU (electronic control unit), wherein the air sac is arranged on a car floor of a transition area between a car front wall plate and the floor and at the position of feet of the car passenger. During collision of cars, the air sac ECU can control the air generator to inflate the air sac according to car state information detected by the sensor, so that the air sac can be inflated to protect the feet of the passenger.

A contact plate for growing cell cultures, bacteria cultures, and the like, comprising a base and a cover. The base has a bottom wall for holding the culture medium and the like, and a circumferential sidewall extending upwardly from the bottom wall and attached thereto. The base further incorporates a flange extending outwardly from the outer periphery of the sidewall. The cover has a top wall, which has a larger diameter than the base sidewall, and a circumferential sidewall extending downwardly from the top wall and attached thereto. The contact plate has a locking means for securely holding the cover to the base of the contact plate in the locked position, wherein the locking means comprises an inter-engaging rib and groove arrangement.

The invention relates to the field of electronic and electrical appliances, and provides an indoor light control device and method for a vehicle. The indoor light control device comprises a vehicle speed acquisition module, an indoor light state acquisition module, an image acquisition module, a positioning module and a control module. The vehicle speed acquisition module is used for obtaining vehicle speed information. The indoor light state acquisition module is used for obtaining the indoor light state information. The image acquisition module is used for obtaining image information. The positioning module is used for obtaining peripheral traffic information of the vehicle. The control module is used for controlling the turning on or off of the indoor light according to the vehicle speed information, the indoor light state information, the image information and the peripheral traffic information. The indoor light control device can judge whether the vehicle indoor light needs to beturned on or off according to the vehicle speed, and can automatically control the turning on and off of the vehicle interior light, thus avoiding frequent manual switching by the driver and improvingdriving experience.

The invention provides an intelligent induction energy-saving lamp and particularly relates to the technical field of lamp lighting. The intelligent induction energy-saving lamp comprises an infrared thermal imaging module, an infrared logic analysis module, light sensors, a light logic analysis module, a time module, a controller, a variable resistor, an energy-saving lamp body and a shell. The intelligent induction energy-saving lamp provided by the invention has the characteristics that the infrared induction is sensitive and dead angles are avoided; the emergence of a human body or an animal can be correctly judged, thereby effectively reducing the number of times that the intelligent induction energy-saving lamp is mistakenly turned on; the brightness of the LED energy-saving lamp body can be changed according to the environment, thereby meeting the various requirements of people for light; the energy-saving lamp body can be automatically turned on within a specific period of time, thereby meeting the various requirements of people for light; and meanwhile, the energy-saving lamp body can be conveniently detached and replaced.

The invention provides an air conditioner with an ultraviolet sterilization function. The air conditioner with the ultraviolet sterilization function comprises an air conditioner shell, an air conditioner panel, an evaporator, a filter screen, a fan system and an air outlet, wherein one end of the air outlet communicates with the fan system, and the other end of the air outlet communicates with the outside; an ultraviolet sterilization device is arranged between the air conditioner panel and the evaporator, and the ultraviolet sterilization device is arranged inside the filter screen through afixing mechanism; a power-off protection system used for triggering a power-off protection function of the ultraviolet sterilization device is arranged inside the air conditioner shell, the power-offprotection system involves a brightness sensing device arranged on the inner side of the air conditioner panel and a main controller, the brightness sensing device is used for sensing the environmentbrightness, and the main controller judges whether the power-off protection function of the ultraviolet sterilization device is opened or not according to the brightness change. When the air conditioner panel of the air conditioner is not closed or the panel is opened in the operation process, the ultraviolet sterilization device can be automatically powered off, and leakage of ultraviolet rays generated by an ultraviolet sterilization lamp is avoided.

The invention discloses a vehicle water-falling detection system based on multi-source information. The vehicle water-falling detection system comprises an ultrasonic water depth detector, humidity sensors, pressure sensors, a speed sensor, an image recognition module and a main control chip. A detection method comprises the steps that the water depth is first detected by using the ultrasonic water depth detector, and when the water depth is less than 0.3m or more than 0.4m, information is sent to the main control chip through the output end of the ultrasonic water depth detector, and the maincontrol chip judges a water falling state of a vehicle, thereby determining whether to open airbags or not; when the water depth reaches 0.3-0.4m, the main control chip judges the water falling stateof the vehicle through the detection information of humidity and pressure; and if the pressure is less than 5KPa at this time, the humidity and speed need to be subjected to data analysis to determine the water falling state of the vehicle. The detection method can accurately judge the water falling depth of the vehicle, and can avoid the occurrence of false opening of the airbags of the vehicle.The vehicle water-falling detection system and detection method based on the multi-source information can better detect the wading condition of the vehicle, thereby judging whether the vehicle fallsinto water or not; and the system is simple and effective.

The invention discloses a novel GaN heterojunction field effect transistor. According to the invention, a P-type GaN buried layer is introduced into a local area of a GaN channel layer of a field effect transistor. The P-type GaN buried layer can improve the heterojunction energy band of the area so as to reduce local channel 2-DEG concentration and a pn junction field board is introduced into theGaN channel layer along the current direction so as to modulate channel electric field. According to the invention, P-type GaN buried layer and groove technology are combined together, so that a threshold value voltage regulation scheme becomes more flexible and threshold value voltage regulation of a larger range can be realized. At the same time, by the electric field modulation effect of the P-type GaN buried layer in the GaN channel layer, the maximal peak value electric field in a device can be reduced effectively and electric field distribution uniformity can be improved. Besides, the P-type GaN buried layer introduces a barrier in a GaN Buffer, so that source and drain electrode punchthrough of the device caused by Buffer electric leakage can be inhibited effectively. Therefore, compared with a traditional groove gating GaN heterojunction field effect transistor, the new structure enlarges the threshold value voltage regulation range effectively and improves the voltage resistance of the device substantially.

The invention provides an elevator control method based on mobile terminal authentication and position induction. The method comprises a position state obtaining step for obtaining the position state of a mobile terminal, the motion state obtaining step for obtaining the motion state of the mobile terminal, a behavior mode affirming step for affirming the behavior mode of the mobile terminal according to the motion state and the position state, and an equipment instruction generating step generating an equipment control instruction according to the behavior mode, wherein the equipment control instruction comprises an elevator control instruction. In addition, the invention provides an elevator control system based on mobile terminal authentication and position induction. By means of the method and the system, the behavior mode of a user can be accurately recognized, whether elevator taking is the purpose or not is judged, and mistaken opening is prevented.

The invention discloses an anti-vibration butterfly valve, and relates to the technical field of valve equipment. The anti-vibration butterfly valve comprises a valve body, a water inlet pipe, a drainage pipe, a butterfly plate component, a frame body, a rack, a clamping part and a limiting mechanism. The anti-vibration butterfly valve has the beneficial technical effects that the situation that the valve is opened or closed by mistake due to the fact that the valve body is vibrated because of being impacted can be avoided, when the anti-vibration butterfly valve is in an opened state, and aclamping block on the clamping part can keep the anti-vibration butterfly valve in the opened state; when the anti-vibration butterfly valve is in a closed state, the anti-vibration butterfly valve can be kept in the closed state by adjusting the direction of the clamping block on the clamping part, the left end of the valve body is fixedly connected with and communicates with the water inlet pipe, the right end of the valve body is fixedly connected with and communicates with the drainage pipe, the butterfly plate component is arranged in the middle of the valve body, the frame body is fixedly connected to the upper end of the valve body, the rack is arranged on the frame body, and the butterfly plate component is in transmission connection with the rack. The clamping part is fixedly connected to the frame body, the clamping part is clamped on the rack, the limiting mechanism is connected on the clamping part in a sliding fit manner, and the limiting mechanism is connected with the clamping part.