A kind of decompression type backflow preventer
Technical field
The present invention relates to valve, particularly a kind of decompression type backflow preventer.
Background technique
In the water supply line; The various safety check that use at present can not strictly limit ducted press water one-way flow; So causing pipeline branch pipe, water system and other system joint etc. that adverse current takes place easily pollutes; Especially city water-supply pipe network, Drinking Water water tank, domestic water pipeline pollute and will bring serious harm to resident healthy in case adverse current takes place, be used on suction booster, the fire pump adapter, production such as chemical device and social security aspect will become potential safety hazard.
The backflow preventer that occurs at present; As China national Department of Intellectual Property on March 24th, 2010 a disclosed name be called a kind of application for a patent for invention of pressure release type backflow preventer; Publication number is CN101676590A; A kind of pressure release type backflow preventer is disclosed in this application for a patent for invention specification; Comprise that water intake ball valve, one-level safety check, secondary safety check and the water outlet ball valve that connects successively, the sluicing reduction valve of bypass are installed between one-level safety check and the secondary safety check; The sluicing reduction valve is divided into the valve gap of sluicing reduction valve and the valve body of sluicing reduction valve, but the piston body that it is characterized in that move left and right be arranged in the inner chamber of sluicing reduction valve and be divided into left chamber and right chamber, left chamber is communicated with total water inlet through the passage on the valve gap of sluicing reduction valve; Right chamber is communicated with through the water intake and the discharge opening of annular seating with the sluicing reduction valve; Be distributed with O-ring seal and inner chamber wall on the piston body circumferential surface and realize slipper seal, the piston body right flank is furnished with sealing gasket and annular seating fitted seal, and is supported with spring between piston body and the annular seating.Owing to its inner safety check, relief valve partly are independent design, need be during installation through a plurality of unit constructions connections, spatial structure is complicated, and therefore installation, dismounting and enforcement maintenance and maintenance are all not too convenient, and cost is higher relatively.
Summary of the invention
Problem to be solved by this invention just provide a kind of simple and reasonable, design decompression type backflow preventer cleverly; Can either guarantee the safe in utilization and life-span; Simultaneously can reduce casting and difficulty of processing and product price greatly again, and installing space little, install and change simple and convenient and keep in repair easily and maintain.
In order to solve the problems of the technologies described above; The present invention adopts following technological scheme: a kind of decompression type backflow preventer; Comprise valve body, be located at the secondary safety check in the valve body; It is characterized in that: be positioned at the diaphragm device that secondary safety check top also is provided with band one-level safety check in the said valve body; Said one-level safety check lower end and secondary safety check upper end are connected, and are provided with the water intake of connecting with one-level safety check upper end on valve body top, are provided with the water outlet of connecting with the secondary safety check in valve body lower portion; The sidepiece of said valve body is provided with overflow hole, and said diaphragm device is positioned at the break-make that is implemented in slide down in-migration change overflow hole in the valve body in the valve body and through the pressure difference of diaphragm device upper and lower end.
Further; Said diaphragm device comprises location one-level safety check and changes the position structure I of overflow hole break-make and be located between position structure I and valve body, to support position structure I and position structure I is moved up and down in valve body realizes overflow hole break-make and the elastic sealing device that makes one-level safety check proper functioning; Said valve body comprises the upper valve body and following valve body of mutual sealed butt joint; Said water intake is located at the upper valve body top; Said water outlet is located at down the valve body bottom, and said overflow hole is located at down the valve body sidepiece, and said secondary safety check is fixed on down in the valve body.
Further, be provided with annular protrusion upwards in the said valve body down, said position structure I comprises the cutting ferrule that is pressed on the annular protrusion; And be located in the cutting ferrule elastic base I with some through holes; The position that on the bottom end of cutting ferrule, contacts with annular protrusion is provided with seal ring, and said one-level safety check is positioned on the elastic base I, and said elastic sealing device comprises support spring and annular diaphragm; The upper end of support spring is against on the bottom end of cutting ferrule; The lower end of support spring is positioned at down in the valve body, and the interior edge of annular diaphragm is fixed on the cutting ferrule, and the outer of annular diaphragm is positioned at down on the valve body upper-end surface and is pressed on down on the valve body fixing by upper valve body.
Further; Said one-level safety check comprise the flap I that is located on the elastic base I and be located at flap I and elastic base I between pressure spring I; And be located at flap I top and cooperate the flap seat I that forms sealing pair with flap I; Flap seat I is fixed on the cutting ferrule, and flap I is withstanding under the effect of pressure spring I on the flap seat I.
Further, be provided with the flow channel that the upper surface with annular diaphragm is communicated with water intake between said cutting ferrule and the upper valve body.
Further, the lower end of said cutting ferrule is provided with the funnel shaped rectifier that the current through the one-level safety check are converged again.
Further; The elastic base II with some through holes is fixed on down in the valve body said secondary safety check in the valve body through being located at down; Said secondary safety check comprise the flap II that is located on the elastic base II and be located at flap II and elastic base II between pressure spring II; And cooperate the flap seat II that forms sealing pair with flap II above being located at flap II, and flap seat II is fixed on down in the valve body, and flap II is withstanding under the effect of pressure spring II on the flap seat II.
Further, said flap I and said flap II coaxial line.Be convenient to produce, install balanced hydraulic pressure during use.
Further, said water intake is provided with inlet connector tube, and inlet connector tube is fixed on the upper valve body through acorn nut I, and said water outlet is provided with outlet pipe connection, and outlet pipe connection is fixed on down on the valve body through acorn nut II.
Further, said elastic sealing device is the elastic ring barrier film, and the interior edge of elastic ring barrier film is fixed on the cutting ferrule, and the outer of elastic ring barrier film is positioned at down on the valve body upper-end surface and is pressed on down on the valve body fixing by upper valve body.
After adopting technique scheme, the present invention has following advantage: one-level safety check and relief valve are combined to form diaphragm device, designs simplification; The active force and the reaction force that make full use of annular diaphragm make the ingenious realization of relief function, and it is compact simple that therefore its structure also becomes, and build diminishes significantly; Pipe joint and valve body are divided into two component connect with acorn nut then, can be convenient to like this change Placement into internal and external threads, flange and cutting ferrule etc., thereby have more usability according to customer requirement; Flap seat and flap etc. adopt corrosion protection, nonhazardous plastics and spring seat and Steel Cable Baffle Ring etc. to adopt stainless steel material, are convenient to processing and batch, and are in light weight, easy mounting, maintenance and maintenance etc.
Description of drawings
Below in conjunction with accompanying drawing the present invention is described further:
Fig. 1 is the structural representation of an embodiment of the present invention;
Fig. 2 is for adopting the structural representation of elastic ring barrier film.
Embodiment
The structural representation of an embodiment of the present invention as shown in Figure 1; A kind of decompression type backflow preventer; Comprise valve body 1, be located at the secondary safety check in the valve body, be positioned at the diaphragm device that secondary safety check top also is provided with band one-level safety check in the said valve body, said one-level safety check lower end and secondary safety check upper end are connected; Be provided with the water intake of connecting with one-level safety check upper end 110 on valve body top; Be provided with the water outlet of connecting with the secondary safety check 120 in valve body lower portion, the sidepiece of said valve body is provided with overflow hole 13, and said diaphragm device is positioned at the break-make that is implemented in slide down in-migration change overflow hole in the valve body in the valve body and through the pressure difference of diaphragm device upper and lower end.
In the present embodiment; Said valve body comprises the upper valve body 11 and following valve body 12 of mutual sealed butt joint; Said water intake is located at the upper valve body top; Said water outlet is located at down the valve body bottom; Said overflow hole is located at down the valve body sidepiece, and said diaphragm device comprises location one-level safety check and changes the position structure I of overflow hole break-make and be located between position structure I and valve body, to support position structure I and position structure I is moved up and down in valve body realizes overflow hole break-make and the elastic sealing device that makes one-level safety check proper functioning.Be provided with annular protrusion 121 upwards in the said valve body down; Said position structure I comprises the cutting ferrule 4 that is pressed on the annular protrusion; And be located in the cutting ferrule with the elastic base I43 of some through holes, the position that on the bottom end of cutting ferrule, contacts with annular protrusion is provided with seal ring 44; Said elastic sealing device comprises support spring 6 and annular diaphragm 14, and the upper end of support spring is against on the bottom end of cutting ferrule, and the lower end of support spring is positioned at down in the valve body; The interior edge of annular diaphragm is fixed on the cutting ferrule, and the outer of annular diaphragm is positioned at down on the valve body upper-end surface and is pressed on down on the valve body fixing by upper valve body.Between cutting ferrule and upper valve body, be provided with the flow channel 15 that the upper surface with annular diaphragm is communicated with water intake; Be provided with the funnel shaped rectifier 5 that the current through the one-level safety check are converged again in the lower end of cutting ferrule.
Said one-level safety check comprise the flap I21 that is located on the elastic base I and be located at flap I and elastic base I between pressure spring I22; And be located at flap I top and cooperate the flap seat I23 that forms sealing pair with flap I; Flap seat I is fixed on the cutting ferrule, and flap I is withstanding under the effect of pressure spring I on the flap seat I.The elastic base II7 with some through holes is fixed on down in the valve body said secondary safety check in the valve body through being located at down; Said secondary safety check comprise the flap II31 that is located on the elastic base II and be located at flap II and elastic base II between pressure spring II32; And be located at flap II top and cooperate the flap seat II33 that forms sealing pair with flap II; Flap seat II is fixed on down in the valve body, and flap II is withstanding under the effect of pressure spring II on the flap seat II.Said flap I and said flap II coaxial line.
In the foregoing description, on said water intake, be provided with inlet connector tube 8, inlet connector tube is fixed on the upper valve body through acorn nut I81, and said water outlet is provided with outlet pipe connection 9, and outlet pipe connection is fixed on down on the valve body through acorn nut II91; In inlet connector tube, be provided with filter 82, filter be shaped as Rotary-table or cone.In addition; Said cutting ferrule comprises following cutting ferrule 41 and is installed on down the last cutting ferrule 42 in the cutting ferrule; The bottom end of following cutting ferrule is provided with the circular groove 411 that seal ring is installed; The interior edge of said annular diaphragm is positioned at down on the cutting ferrule upper-end surface and is pressed on down on the cutting ferrule by last cutting ferrule fixing, and the upper end of said support spring is against play on the bottom end of cutting ferrule, and rectifier and elastic base I are interlockingly connected through last cutting ferrule and following cutting ferrule equally and compress fastening.Flap seat II is set as integrative-structure with following valve body.
Working principle of the present invention is following:
1, just often action: when press water gets into the upper valve body valve pocket from water intake, with one-level safety check and the whole pushing downwards of position structure I, following cutting ferrule is pressed on the annular protrusion and through seal ring and guarantees to seal; Make overflow hole be in closed condition; Thereby the intermediate cavity between one-level safety check and the secondary safety check forms airtight cavity, when the one-level safety check is opened, and the press water loss that is under pressure when getting into intermediate cavity; Then the secondary safety check is opened; Press water gets in the following valve body valve pocket, the loss that is under pressure once more, and press water flows out from water outlet through whole valve body.Press water is to the effect of annular diaphragm in the upper valve body valve pocket owing to receive, and overflow hole remains closed condition, and overflow does not take place; From the refluence of valve body valve pocket generation down, just be prevented at the secondary safety check.When first safety check takes place unusual; Block like rubbish, when can't accept the pressure loss, the annular diaphragm of the water effect that is under pressure detects the pressure of supply water of press water and the pressure difference of intermediate cavity; One-level safety check and position structure I integral body are moved up; Open relief valve, release pressure, poor up to reaching normal pressure.
When 2, taking place to flow backwards: if second safety check has taken place unusually; When blocking like rubbish, the water of water outlet the pressure of intermediate cavity is risen adverse current or one-level, secondary safety check have all taken place unusually, when blocking like rubbish; Get into from water intake that the water of upper valve body valve pocket is normal to be flowed into and get into down from the water outlet adverse current that the reverse intermediate cavity that flows to of water of valve body valve pocket rises its pressure; The annular diaphragm of water effect of being under pressure detects the pressure of supply water of press water and the pressure difference of intermediate cavity, and one-level safety check and position structure I integral body are moved up, and overflow hole is opened; Discharge the water of adverse current, can not cause the water adverse current situation of upper valve body valve pocket.
When 3, backsiphonage phenomenon took place: even negative pressure appearance takes place in the distribution pipe, the one-level safety check can prevent adverse current.If when the one-level safety check had abnormal conditions, rubbish was blocked, annular diaphragm detect press water pressure of supply water and intermediate cavity pressure difference or detect the information that this pressure difference diminishes, one-level safety check and position structure I integral body are moved up, overflow hole is opened.Final for understanding the negative pressure appearance of disappear water intake and the generation of distribution pipe side, from the overflow hole suck air.
Also having a kind of situation in addition is exactly the upper end that elastic device is located at cutting ferrule; Cutting ferrule is pushed away downwards; Just realize overflow in the time of can between the pressure of the pressure of supply water of water intake and intermediate cavity, having big pressure reduction like this, practical with respect to the situation that the one-level safety check is accurate.
Said in addition elastic sealing device also has a kind of structural type; Employing elastic ring barrier film 6 ' as shown in Figure 2; The interior edge of elastic ring barrier film is fixed on the cutting ferrule, and the outer of elastic ring barrier film is positioned at down on the valve body upper-end surface and is pressed on down on the valve body fixing by upper valve body.Save support spring like this, but the requirement of elastic ring barrier film is improved, possess sealing and spring function simultaneously.
Except that above-mentioned preferred embodiment, the present invention also has other mode of execution, and those skilled in the art can make various changes and distortion according to the present invention, only otherwise break away from spirit of the present invention, all should belong to the defined scope of accompanying claims of the present invention.