2714results about "Equalizing valves" patented technology

The invention relates to the technical field of balance valves, and discloses a load compensation balance valve which comprises a balance valve body and an adjusting nut, a locking cap is in threaded connection with the outer arc surface of the adjusting nut, the right side of the locking cap is in contact with a main valve element spring, and the end, away from the locking cap, of the main valve element spring is in contact with a tip cone. The function of a one-way valve of one balance valve element assembly is canceled, so that oil inlet from a V port to a C port depends on the pressure of a control oil port and generates driving pressure through a throttling network composed of a specific throttling hole, the one-way valve and a bypass throttling hole, and the other balance valve element assembly obtains the driving pressure equal to the pressure of the control oil port through an independent throttling hole. A pressure difference is formed to realize sequential opening of the two assemblies; the linkage logic inhibits the jitter of the multiple feedback system under the negative load, stabilizes the falling speed of the arm support, and avoids the risk of overturning of the whole machine caused by the dynamic load.

The invention discloses high-pressure fuel gas pressure regulating equipment in the technical field of fuel gas pressure regulating equipment, which comprises a valve body, and a valve rod, a reset spring and a gas inlet box which are arranged on the valve body, a valve seat and a diaphragm are arranged on the valve rod, the gas inlet box is communicated with a gas outlet of the valve body through a guide pipe, and a detection assembly is arranged in the gas inlet box; the detection assembly comprises an air pressure detection piece and a displacement detection piece, and a warning indicator is arranged on the air inlet box and used for giving an alarm when the air pressure detection piece detects that the air pressure below an inner cavity of the air inlet box is lower than a threshold value and the displacement detection piece does not detect that the valve rod moves. The high-pressure gas pressure regulating equipment is detected through the detection assembly, when the air pressure detection piece detects that the air pressure below the inner cavity of the gas inlet box is lower than a threshold value and the displacement detection piece does not detect that the valve rod moves, the warning indicator gives an alarm to remind a user, so that problems can be found in time, further deterioration of the faults is avoided, and the service life of the user is prolonged. And the probability of potential safety hazards is reduced.

The utility model discloses a one-way valve with a pressure relief protection function, and particularly relates to the technical field of one-way valves, which comprises a valve body, a discharge pipe is arranged at one end of the valve body in a penetrating manner, an outer valve sleeve is arranged on one side of the valve body in a penetrating manner, a pressure relief mechanism is arranged in the outer valve sleeve, and the pressure relief mechanism comprises a pressure relief valve seat arranged in the outer valve sleeve. A guide groove is formed in the outer valve sleeve, a guide ring is slidably arranged in the guide groove, a pressure relief valve element is fixedly arranged in the guide ring, a pressure relief spring is fixedly arranged at the top of the pressure relief valve element, an adjusting disc is slidably arranged on the inner wall of the valve body, and a threaded rod is rotatably arranged on one side of the adjusting disc. When the fluid pressure abnormally rises, the pressure relief channel can be automatically opened, the one-way valve and a conveying system are effectively protected, the position of the pressure relief valve element can be conveniently and manually adjusted, pressure relief parameters are flexibly controlled, and the requirements of different working conditions are met.

The pressure release valve comprises a shell and a fixing sleeve arranged on the shell, an installation cavity is formed in the shell, an electromagnetic coil assembly is arranged in the installation cavity, the magnetic isolation sleeve is inserted in the installation cavity, the magnetic isolation sleeve is connected between the shell and the fixing sleeve in an abutting mode and isolates the installation cavity, and the electromagnetic coil assembly is arranged in the magnetic isolation sleeve. A movable valve element is arranged on the magnetism isolating sleeve in a sliding mode, and the end of the movable valve element is connected with a sealing piece.

A breakaway valve for a cryogenic fluid tank includes a tank-side valve and a nozzle-side valve. The tank-side valve is connected to and forms a first vacuum-insulation layer with a first jacketed hose. The first jacket support includes first bellows configured to reduce heat transfer with the first vacuum-insulation layer and one or more first bellow supports that include first teeth inserted between and engaging the first bellows to provide structural support to the first bellows. The nozzle-side valve is connected to and forms a second vacuum-insulation layer with a second jacketed hose. The second jacket support includes second bellows configured to reduce heat transfer with the second vacuum-insulation layer and one or more second bellow supports that include second teeth inserted between and engaging the second bellows to provide structural support to the second bellows.

The invention discloses a single-action pressure reduction diaphragm type pressure flow amplifier in the field of industrial flow control. The single-action pressure reduction diaphragm type pressure flow amplifier comprises a machine body, a valve core, a flexible diaphragm, an exhaust assembly, a large pressure reduction device and a small pressure reduction device. An adjusting cavity, an air inlet cavity, an air outlet cavity, an air inlet channel and an air outlet channel are formed in the machine body, the air inlet channel is communicated with the air inlet cavity, the air outlet cavity is communicated with the air outlet channel, the valve core is arranged between the air inlet cavity and the air outlet cavity, the valve core is pushed through the flexible diaphragm and the exhaust assembly, and the compressed air flow and pressure intensity between the air inlet cavity and the air outlet cavity can be adjusted; when the pressure intensity of the adjusted air is relatively low, the small pressure reducing device is used for reducing pressure; and when the pressure intensity is high, the large pressure reducing device is used for reducing pressure. The diaphragm structure design is adopted, the flow and the pressure intensity of compressed air are adjusted through reciprocating motion of the flexible diaphragm, the pressure intensity of the adjusted air is reduced through the two pressure reducing devices, and the diaphragm structure can be better suitable for application scenes where the pressure intensity of the adjusted air is high.

The valve device comprises a driving assembly, a valve seat assembly, a diaphragm and a valve element assembly, the valve seat assembly is fixedly connected with the driving assembly, the valve seat assembly is provided with a valve port, the driving assembly is in transmission connection with the valve element assembly, the valve element assembly can axially move to open or close the valve port, and the diaphragm is arranged in the valve element assembly in the axial direction of the valve device. At least part of the diaphragm is arranged between the driving assembly and the valve seat assembly; the valve device is provided with a liquid inlet cavity and a balance cavity, the valve element assembly is provided with a balance channel, the balance channel is communicated with the balance cavity and the liquid inlet cavity, the wall part limiting the mounting hole and the valve element assembly are arranged in a sealed mode, and the diaphragm limits part of the wall part of the balance cavity. Part of the working fluid can enter the balance cavity through the balance channel, and the driving force of the valve device can be reduced.

The utility model relates to the technical field of drain valves, and discloses a drain valve based on gravity control, the drain valve comprises a valve body, the interior of the valve body is provided with a cavity, the valve body comprises an inner side surface and an outer side surface opposite to the inner side surface, and the inner side surface is provided with a liquid inlet; a liquid outlet is formed in the outer side surface, and the liquid outlet can be communicated with the liquid inlet through the cavity; the gravity ball is arranged in the cavity of the valve body; the sealing element is arranged between the gravity ball and the liquid inlet and is used for sealing the liquid inlet; the inclined plane structure is arranged on the other side, opposite to the sealing piece, in the valve body, the side, facing the gravity ball, of the inclined plane structure is provided with an upward inclined plane, and the shortest distance between the inclined plane and the sealing piece is smaller than the diameter of the gravity ball. According to the embodiment of the invention, the manufacturing and maintenance cost of the drain valve can be reduced, and the drain effect of the drain valve can be improved.

The present application relates to pipeline system damping and noise reduction technical field, provide a kind of active noise cancellation pressure relief valve, comprising: valve body, with the liquid inlet cavity and pressure relief cavity being communicated are formed;Bypass pipe, with liquid inlet cavity is communicated;Piezoelectric actuator and pressure relief component, pressure relief component includes adjusting piece, pressure relief elastic piece and pressure relief valve core, pressure relief valve core and pressure relief elastic piece are set in pressure relief cavity, adjusting piece is movably arranged on valve body, piezoelectric actuator is arranged on adjusting piece, pressure relief elastic piece is pressed between piezoelectric actuator and pressure relief valve core;Piezoelectric actuator is configured to drive pressure relief elastic piece, to eliminate the transient noise caused by pulsating pressure when pressure relief valve core moves.The active noise cancellation pressure relief valve provided by the present application introduces active noise cancellation technology into the active noise cancellation pressure relief valve pulsating noise control by arranging piezoelectric actuator, can be adjusted by pressure relief elastic piece The force exerted on the pressure relief valve core can eliminate the transient noise caused by pulsating pressure when the pressure relief valve core moves.

The invention provides a three-position seven-way valve, a chromatographic analysis system and a working method of the chromatographic analysis system, and relates to the technical field of liquid chromatography. The three-position seven-way valve comprises a rotor, a valve head and a valve body, the valve head is provided with a pressure relief opening and six functional ports, the rotor is provided with a first flow guide groove, a second flow guide groove, a third flow guide groove and a pressure relief groove, and communication of different flow paths is achieved through rotation of the rotor. During mode switching, high-pressure fluid in the quantitative loop is actively guided to the pressure relief opening through the pressure relief groove to release pressure, uncontrolled expansion towards a sample injection needle or a pump end is avoided, backflushing interference is effectively reduced, reverse pushing or disturbance of a sample is prevented, and the accuracy and repeatability of the sample suction volume in the sample loading stage are guaranteed. The integrated pressure relief design does not need an external device, a flow path is simplified, and the integration level and reliability of the system are improved. The device is suitable for high-precision suction type sample injection, and the sample injection stability and the chromatographic analysis reproducibility are remarkably improved.

The invention provides an integrated pressure protection double-layer corrugated pipe vibration reduction pipe, and belongs to the field of vibration absorbers. An interlayer cavity is formed in the pipe wall of the vibration reduction pipe; gap grooves are formed in the middles of the outer end faces of the flange plates, so that steps are formed on the outer end faces of the flange plates around the edge portions of the gap grooves, and inlet holes and outlet holes are formed in the gap grooves of the two flange plates respectively. The safety valve and the one-way valve are arranged in the interlayer cavity and connected to the inlet hole and the outlet hole, the safety valve allows or limits the medium to enter the interlayer cavity through the inlet hole according to whether the external pressure exceeds the preset pressure, and the one-way valve limits the medium to flow out of the interlayer cavity only through the outlet hole. The safety valve is arranged, so that a medium in the inner layer of the pipeline enters the interlayer cavity, the pressure value in the inner layer of the pipeline is reduced, the pressure of the medium is prevented from exceeding the yield limit of an inner-layer corrugated pipe material, and the medium entering the interlayer cavity can flow back to a low-pressure area through the one-way valve; and the safety and the reliability of the double-layer corrugated pipe vibration reduction pipeline are improved.

An air turbine and a power generation device, the air turbine comprising a chamber, a valve and a rotor. The chamber comprises a first opening communicating with the atmosphere; the air pressure in the chamber is adjustable, and the difference between the air pressure in the chamber and the atmospheric pressure comprises a first air pressure difference and a second air pressure difference; the valve is connected with the chamber and is configured to open under the action of the first air pressure difference to form a first air flow by the chamber communicating with the atmosphere through the valve and the first opening respectively, and to close under the action of the second air pressure difference to form a second air flow by the chamber communicating with the atmosphere through the first opening, the directions of the first air pressure difference and the second air pressure difference being opposite; the rotor is configured to rotate under the drive of the second air flow. The air turbine can be used for power generation to convert the kinetic energy of the rotor into electrical energy, for example, the first air pressure difference and the second air pressure difference are obtained by utilizing the fluctuation of waves, and ultimately the wave energy is converted into electrical energy.

The invention discloses a pipeline gas safety valve control method and system, and relates to the technical field of gas safety control, and the method comprises the following steps: obtaining the operation data of a gas pipeline, constructing a gas pipeline operation state portrait, extracting evolution characteristics, and generating an operation state characteristic vector; according to the running state feature vector, grading the running state, dynamically correcting a division threshold value according to historical running data, and outputting a corresponding safety valve control decision instruction; the safety valve is driven to execute opening and closing actions according to the safety valve control decision instruction, the consistency between the actual action state of the valve and the control instruction is verified, and valve execution result data is generated; writing back and updating the operation state feature construction process according to the valve execution result data; through the running state portrait and closed-loop feedback control, the problems that in traditional pipeline gas safety valve control, the control decision adaptability is not high, and the execution result lacks feedback are solved.

The invention provides a valve device. The valve device comprises a main valve component, a bypass valve component and a communicating pipe. When the medium pressure difference of the inflow runner part and the outflow runner part of the main valve part reaches the preset value, the first valve port part of the bypass valve part can be opened for pressure relief, the bypass valve part and the main valve part are integrated, and the problem that the pressure relief function is lost due to reverse installation of the bypass valve part does not exist. The bypass valve component is provided with the pressure gauge connector part, the bypass valve component has a bypass function and a cut-off function, a channel between the pressure gauge connector part and the main valve component can be cut off, and the safety problem when the pressure gauge is connected is solved.

A break check valve can include one or more rotating members configured to rotate to alter the break check valve from an open position to a closed position upon dislocation of a pipe system fitting, the break check valve being altered from an open position to a closed position when acted upon by fluid within a piping system.

The invention belongs to the technical field of pipeline valves, and particularly relates to a resistance-free prevention valve. Comprising a discharge valve, a main valve and two check valves, and the two check valves are fixedly installed in an inner cavity of the main valve and divide the inner cavity of the main valve into an inlet cavity, a middle cavity and an outlet cavity. When the pressure difference between the inlet cavity and the middle cavity is larger than a set value, the discharge valve is closed, and when the pressure difference between the inlet cavity and the middle cavity is continuously smaller than the set value, the pressure difference discharge valve is opened, discharge and pressure reduction are conducted through the discharge channel, and the discharge valve is closed until the pressure difference between the inlet cavity and the middle cavity recovers to the set value; the anti-misoperation device is arranged in the discharge valve, so that misoperation discharge of the discharge valve caused by water pressure fluctuation in a pipeline can be effectively prevented, and water pressure loss is avoided; valve membrane abrasion is reduced, and the service life of the discharge valve is prolonged; and the pressure difference during drainage can be adjusted according to working conditions and requirements.

The disclosure relates to a closing aid for a luggage compartment (2) located at the front of a vehicle (1). The compartment can be sealed—at least partly or almost completely—from the outside air. The closing aid includes a valve system (10) that activates if there's a sudden increase in pressure inside the closed luggage compartment. When activated, the valve allows pressure to be released from the sealed compartment to the outside air.

A hydrogen pressure reducer for a hydrogen supply system of a hydrogen fuel automobile relates to the technical field of hydrogen pressure reducers and comprises a valve body, a diaphragm type pressure reducing mechanism, a pilot-operated electromagnetic valve, a gas inlet and a gas outlet. The interior of the valve body is divided into a high-pressure cavity and a low-pressure cavity through the valve The diaphragm type pressure reducing mechanism is composed of a valve element assembly, a diaphragm assembly and a pressure adjusting assembly which cooperate to enable the output pressure of the air outlet to be kept stable, and assembly errors are eliminated. The valve element assembly is provided with a necking part to adjust the opening degree of a throttling hole, and accurate control is achieved. The base provides guiding constraint, and reliable sealing is ensured. The diaphragm assembly adopts a supporting disc, a diaphragm, a pressing disc and a locking nut fixing structure, so that the diaphragm is prevented from deforming, and the service life is prolonged. The pressure adjusting assembly comprises an upper cover, a pressure adjusting spring, a pressure adjusting spring seat and a pressure adjusting stud, and the pressure adjusting accuracy and stability are guaranteed. The overall reliability, sensitivity and safety of the hydrogen pressure reducer are improved.

The invention belongs to the technical field of automobile shock absorber electromagnetic valves, and particularly relates to a hydraulic shock absorber electromagnetic valve for vehicle testing. A backflow channel communicated with an overflow cavity and a pressurizing cavity is arranged on a partition plate, a one-way valve leading to the pressurizing cavity is arranged on the backflow channel, so that oil flowing into the overflow cavity flows back into the pressurizing cavity to react on a pressurizing seat, and the oil in a main liquid cavity needs to have higher pressure when the pressurizing seat is pushed away from a main valve body; and the oil liquid pressure difference between the liquid inlet and the liquid outlet is further increased, the damping force of the oil liquid in the electromagnetic valve is increased, and the vibration reduction performance of the vibration damper is improved. Compared with an electromagnetic valve of a shock absorber in the prior art, when the power-on amount of the electromagnetic coil is certain, the electromagnetic valve provides larger damping force for the vehicle shock absorber; on the contrary, when the damping force needed by the vehicle shock absorber is fixed, the electromagnetic valve consumes less electric energy, the number of times of vehicle charging in the vehicle driving evaluation test process is reduced, the vehicle research and development test efficiency is improved, and electric energy is saved.

The invention belongs to the technical field of engineering elements, and particularly relates to a valve, in particular to a combination valve and a using method thereof. The combination valve comprises a valve body, an air chamber, a fluid chamber and a valve core, the piston is arranged in the air chamber in a lifting manner; the valve element is arranged at the bottom of the piston and used for opening and closing a flow channel in the valve body; the air inlet pipe is arranged on one side of the valve body and communicates with the air chamber cavity through an air channel; the adjusting assembly is arranged in the air inlet pipe in a sliding manner; when the air inlet pipe conveys compressed air into the air chamber cavity, the compressed air pushes the adjusting assembly to move in the direction of the piston so as to open the air channel. After the valve element closes the flow channel, the air cavity in the outer wall of the adjusting assembly communicates with the air chamber cavity through the air channel; if the air pressure in the air inlet pipe fluctuates, the adjusting assembly slides left and right in the air inlet pipe, and the air cavity is always communicated with the air chamber cavity so that the pressure in the air chamber cavity can be constant.

The utility model discloses a one-way valve applied to an automobile suspension system, and belongs to the technical field of automobile parts, the one-way valve comprises a valve body, a valve core, an elastic piece and a ball body, the valve body is of a circular tube structure, two ends of the valve body are respectively a lead-in port and a lead-out port, the valve core is installed in the valve body, and the elastic piece is installed in the valve body. At least three supporting feet are arranged on the outer surface of the valve element and abut against the inner wall face of the valve body, a fluid channel for fluid to pass through is reserved between the outer surface of the valve element and the inner wall face of the valve body, and a ball is installed at the end, close to the valve body guide-in opening, of the valve body through an elastic piece. And the ball body moves to one side of the guide-in opening under the action of the elastic piece to block the guide-in opening. The structural design of the one-way valve is optimized, the fluid flow which can pass through is effectively improved, and the one-way valve is simple and reliable in structure.

The invention discloses a high-pressure straight-through plunger type throttle valve, and particularly relates to the technical field of throttle valves, the high-pressure straight-through plunger type throttle valve comprises a valve body, a plunger rod, a limiting fixer and a through-flow seat, a straight-through flow channel is arranged in the valve body, a plunger rod mounting hole is further formed in the valve body, the plunger rod is rotatably mounted in the plunger rod mounting hole, and the plunger rod is rotatably mounted in the through-flow seat. A limiting fixator is detachably installed at the position, corresponding to the top end of the plunger rod, of the valve body, a channel hole is formed in the bottom end of the plunger rod, the through-flow base is detachably installed in the channel hole, and through opening sealing rings are arranged at the positions, corresponding to the inlet end and the outlet end of the through-flow base, of the outer surface of the plunger rod. The valve body is of a channel straight-through type structure, the energy consumption loss of equipment is reduced, the direction of a medium flow channel does not need to be changed, the occupied well site space is small, the layout problem is solved, meanwhile, additional equipment brought by an angle type fixed throttling valve is reduced, cost is reduced, and disassembly and assembly are more convenient.

The invention relates to the technical field of gas cylinder valves, and discloses a pulse type oxygen valve regulation and control device which comprises a shell, the shell is provided with at least one sunken gas inlet bin which is annularly distributed at equal angles, a rotating bin is arranged in the center of the shell, a sliding sleeve is arranged on the side face of the gas inlet bin, and the rotating bin is provided with a rotating shaft. The center of the rotating bin is rotationally connected with a rotating discharging pipe, the side wall of the rotating discharging pipe communicates with a side inlet pressure pipe, the side inlet pressure pipe is slidably connected to the interior of the sliding sleeve, and an air inlet groove is formed in the inner side wall of the sliding sleeve; the elastic coefficient of the torsion spring of the discharge pipe can be increased, under the effect of the lever principle, the acting force of gas driving the rotary discharge pipe to rotate is reduced, when the rotary discharge pipe has elastic fatigue, only the torsion spring needs to be slightly twisted, and the problem of partial elasticity loss caused by the elastic fatigue can be counteracted; the problem that the stable pressure stability is reduced due to elastic fatigue caused by long-term spring application is solved.

Disclosed is a rupture disc assembly for use in making a temporary seal in a vessel such as a casing string. The rupture disc assembly may include a rupture disc having a side surface that has a shallow angle taper inward towards a bottom surface of the rupture disc, and a mounting apparatus to support the rupture disc so that the rupture disc forms the temporary seal. When a disc working pressure is applied to a top surface of the rupture disc, engagement / force transmission between the rupture disc and the mounting apparatus produces enough radial compression in the rupture disc due to the shallow angle taper to significantly mitigate or cancel tensile stresses thereby avoiding the rupture disc from breaking. The rupture disc may be configured to break when the rupture disc is subjected to a disc working pressure that is greater than the disc rupture pressure, thereby removing the temporary seal. An axial abutment surface feature may be provided which is configured and operable to limit downward axial movement of the rupture disc relative to said disc support mechanism and thus be operable to restrict the amount of compression said tapered wall surface of said disc support mechanism can exert on said at least a portion of said rupture disc when the top surface of the rupture disc is subjected to said hydraulic pressure within the well.

A pulsation dampener includes: a centerbody assembly having: a chamber including a first opening bounded by a wall defining a first surface; an outlet port communicating with the chamber; an inlet port communicating with the chamber; a flexible first diaphragm, wherein a perimeter of the first diaphragm is bonded to the first surface forming a seal that blocks the passage of fluid; a first cap disposed adjacent the first diaphragm, defining a first cavity between the first cap and the first diaphragm; an inlet orifice formed in the first cap communicating with the first cavity; an exhaust orifice formed in the first cap communicating with the first cavity; and a valve seat disposed in the first cavity in fluid communication with the exhaust orifice. The first diaphragm is moveable between an open position spaced away from the valve seat, and a closed position sealed against the valve seat.

Disclosed is a valve apparatus having a first pressure compensation valve, a first, gas-tight, cap-like membrane device, and a gas-permeable, moisture-permeable, and yet water-impermeable second membrane device. The first pressure compensation valve, in particular a back-pressure valve, having a first valve housing, which limits a pressure compensation opening and comprising a housing side and a covering side, comprising or consisting of a first, gas-tight, cap-like membrane device covering a first pressure compensation opening and releasing the first pressure compensation opening from a predetermined negative pressure prevailing on the housing side in order to enable a pressure compensation between a housing device and an environment, and a gas-permeable, moisture-permeable, and yet water-impermeable second membrane device arranged on the covering side and in series to the first membrane device, covering a second pressure compensation opening and preventing water entry into the valve housing and thus into a housing device.

The utility model relates to the technical field of valves, in particular to a water flow regulating valve which comprises a valve body, an inner cavity is formed in the valve body, a water outlet pipe communicated with the inner cavity of the valve body is arranged on the valve body, and a first through hole and a second through hole are formed in the top surface and the bottom surface of the valve body respectively in a penetrating mode. The first through hole and the second through hole are coaxially formed, a water inlet pipe is coaxially fixed at the second through hole, the inner end of the water inlet pipe is sealed, a plurality of water outlet holes are formed in the water inlet pipe in the inner cavity in a penetrating mode in the circumferential direction, a movable pipe is coaxially fixed in the first through hole, and the inner end of the movable pipe extends into the inner cavity and is arranged on the water inlet pipe in a sleeving mode; the movable pipe is in transmission connection with a driving mechanism. By controlling the up-and-down moving distance of the movable pipe, the number of the water outlet holes in the water inlet pipe shielded by the movable pipe can be controlled, so that the water outlet amount of the water inlet pipe through the water outlet holes is controlled, the water outlet flow of the water outlet pipe is adjusted, and more accurate flow control is achieved.

The invention relates to a steam pressure cooker with a combination valve and a floating check valve, the steam pressure cooker comprises a cooker body, a cooker cover, a steam inlet valve, a steam release valve, the combination valve and the floating check valve, the steam inlet valve and the steam release valve are both arranged on the barrel wall of the cooker body and are communicated with the interior of the cooker body, a steaming box is suspended in the cooker body, and a cooker cover locking ring capable of locking the cooker cover and the cooker body is arranged on the outer side of the cooker cover. A first through hole and a sixth through hole are formed in the cooker cover, the combination valve is arranged in the first through hole, the top and the bottom of the combination valve extend out of the first through hole, and the floating check valve is arranged in the sixth through hole. The steam cooker has the function of heating or cooking through steam, and has the advantages of being good in heat preservation effect, convenient to operate and high in safety and having the self-locking function.

A pressure maintaining valve with a flow guide groove in a valve element seat comprises a valve body, a valve cover, the annular valve element seat made of rubber materials, a shaft core part, an elastic assembly, a pressure adjusting spring and an adjusting cap, the annular valve element seat is arranged in a seat cavity, an inverted-cone-shaped core part is matched with the end of the annular valve element seat, a core rod part penetrates through the annular valve element seat, and the valve element seat is provided with a flow guide groove. The head penetrates through the elastic assembly, the baffle disc is attached to the elastic assembly, and the head and the elastic assembly are fixed; the edge of the elastic assembly is embedded into a counter bore of the movable cavity, the valve deck is buckled with the movable cavity and fixes the elastic assembly, and the pressure adjusting spring is arranged in the inner threaded sleeve and abuts against the elastic assembly. And the adjusting cap is screwed with the internal thread sleeve and is matched with the pressure adjusting spring. The inverted-cone-shaped core part is matched with the air inlet end of the circular-ring-shaped valve element seat, the pressure of the air inlet cavity and the pressure of the air outlet cavity are changed, and the inverted-cone-shaped core part can adjust the size of the air inlet end of the axial air groove. The device adapts to different pressures and keeps constant output.

The invention belongs to the technical field of cut-off valves, and particularly relates to an earthquake cut-off valve which comprises a valve body, a valve core, a valve core, a valve core, a valve core and a valve core. The valve clack is arranged in the valve body, is perpendicular to the cut-off opening and can block or open the cut-off opening; the valve cover is arranged at the upper end of the valve body, and a through rod hole is formed in the valve cover; the clack driving mechanism is arranged on the valve cover and can change the position of the valve clack, so that the open-close opening is blocked or opened; wherein the clack driving mechanism comprises a valve rod, a valve rod, a piston rod, a piston rod, a piston rod, a piston rod and a piston rod, the flap driving assembly is matched with the valve rod; the clack driving assembly enables the valve rod to drive the valve clack to be located above the on-off opening in the normal state, so that the on-off opening is opened, and the flowing channel is communicated. When the clack driving assembly vibrates violently, the valve rod drives the valve clack to block the on-off opening so that the flowing channel can be disconnected.