Backwash filter
Technical field
The present invention relates to the filter that liquid filtering is used, especially a kind of filter with backwashing function.
Background technology
Protection water resource and using water wisely are lived closely bound uply with people, and the utilization again of water resource is particularly important.Water for industrial use, air-conditioning cooling circulating water, carwash circulating water, boiler feed water, bathing pool, swimming pool water, chemical pharmaceutical water, well water, river or the like, all need to carry out the filtration treatment of water, it is the only way which must be passed that water resource is utilized again, because the method that tradition is filtered with chemical substance seldom adopts, mostly adopt physical cleaning method filter, remove the middle impurity that anhydrates by the mechanical filter principle.Mechanical filter is the most frequently used equipment, traditional mechanical filter, medium is finished filtration through filter opening to the filter screen outside from the filter screen inner chamber, and in this process, foreign material are deposited on filter screen bottom or invest on the filter screen inwall, the foreign material that are slightly larger than filter opening then are embedded in the filter opening, when opening bleeder valve (or lower cover), medium can be deposited on the foreign material of filter screen bottom by venting, but can not wash away the foreign material that adhere to or embed, because this moment, medium was still from inside to outside the direction of exerting pressure of filter screen, continue to compress.Gradually along with the increase of adhering on the filter screen with insert, the circulation area of filter screen can reduce, and the flow resistance of filter increases, and until obstruction, produces secondary pollution simultaneously, causes changing filter screen and the increase expense.For addressing this problem, the most original method is to take out filter core manually to clean, workload is big, cleaning quality do not guarantee, and is too much for avoiding wash number, employing also arranged than the large mesh filter screen, but filtering accuracy is low, also have and adopt two filters that are used alternatingly that switch in parallel,, easily cause equipment breakdown because the filter screen flow area changes before and after switching." a kind of filter that uses the self-cleaning filter core " of Chinese patent 90201648.2, it realizes the medium backwash by backwashing pump, this scheme need increase the equipment backwashing pump.The utilization of " automatic backwashing filter " of Chinese patent 02149389.8 is filtered valve plate and firm and hard existing the filtration and backwashing function of backwash valve, filtering valve plate and backwash valve plate closes on demand or opens, flushing process need dispose power, water (flow) direction is constant when filtering and washing, probably the foreign material that embed filter opening are difficult for being pulled away, so its backwash effect remains be facts have proved.
Summary of the invention
The present invention is directed to the defective of prior art, propose a kind ofly to utilize pressure medium in the filter to change the MEDIA FLOW path to realize filtering conversion with washing capacity, backwash filter with superior flushing performance.
According to design of the present invention, its embodiment is:
A kind of backwash filter, it comprises housing and the loam cake with medium import, outlet and sewage draining exit, and housing bottom is provided with the ball valve that connects sewage draining exit, is provided with the filter screen of band filter opening in the housing, it is characterized in that described housing internal upper part is provided with spacer ring; Be covered with the lower port that stretches into the housing inner chamber on described; Described filter screen radial location is installed in the housing and can moves up and down along housing, be provided with spring in filter screen and the housing at the end, filter screen is provided with the shoulder that changes medium runner, this shoulder realizes filtering by the switching that contacts with loam cake lower port or housing spacer ring respectively and the function of flushing is changed, and also is provided with the dielectric fluid pressure energy in the filter screen and converts the impeller that liquid flowing energy drives gyration to.
Described filter screen radial location is installed on the uniform upwardly extending guide wall of 4 couple in the end in the housing, and moves up and down along guide wall.
Compared with prior art, the unique simple mechanism design of the present invention is operated by easy keying and is changed the media flow path, make that medium flows to inner chamber from the filter screen outer wall when filtering, and when flushing MEDIA FLOW oppositely rush at filter screen from the filter screen inner chamber, can make the impurity that is attached to screen wall and the embeds filter opening discharge that comes off effectively, the impeller of rotation can convert the hydraulic pressure of medium to the kinetic energy of liquid stream, rotate the directive filter screen with the speed that is several times as much as the pipeline flow velocity for 360 ° from the impeller nozzle, produce enough big flushing ability, guarantee in time several seconds, to remove the foreign material on the filter screen, flushing process need not to dispose power, be specially adapted to family expenses and commercial water filter, can adopt thinner, the more filter screen of number to obtain purer filter medium, is removed the expense of changing filter screen from.
Description of drawings
Fig. 1 filters the status architecture schematic diagram for the present invention.
Fig. 2 is the A-A cutaway view of Fig. 1.
Fig. 3 is a backwash status architecture schematic diagram of the present invention.
Fig. 4 is the B-B cutaway view of Fig. 3.
The specific embodiment
Embodiments of the present invention is further illustrated in conjunction with above-mentioned accompanying drawing more below.
Referring to Fig. 1-4, backwash filter has the housing 3 of a drum shape, and the sewage draining exit of housing bottom connects able to turn on or off ball valve 7, and the interior end is evenly equipped with 4 pairs of upwardly extending guide wall 11, and internal upper part is provided with spacer ring 9, and the top is opening-like.Loam cake 1 is fixed in case top, the two ends of loam cake be respectively medium import A and the outlet B, its import A communicate with housing formation runner 10, on be covered with the lower port 2 that stretches into the housing inner chamber.Be provided with filter screen 8 in the housing, be radially positioned in and move up and down in the housing guide wall and can not rotate, the filter screen bottom sealing, and be provided with spring 6 in the housing, periphery has a lot of filter openings at the end, and the top through hole communicates with upper cover outlet B, filter screen is provided with shoulder 4, can contact with housing spacer ring 9 with loam cake lower port 2 respectively, switch and change the filter media flow direction, realize filtering and the washing capacity conversion.Filter screen adopts double filter screen, and upper filter screen and lower filter screen weld one up and down.Be provided with impeller 5 moving up and down in the filter screen, this impeller nozzle and filter screen radial shape are at an angle, this angle makes impeller the dielectric fluid pressure energy be converted to the liquid flowing energy of flushing filter screen, in the flushing filter screen, make impeller obtain gyration power, the impeller nozzle is rotated the directive filter screen with regard to 360 °, promptly washes all opening of sieves with enough big flushing ability.
Dynamic structure of the present invention and operation principle thereof are described below:
Duty is filtered for filter in Fig. 1~2, this moment, ball valve was in closed condition, the former spring that is in compressive state is pushed filter screen to top along guide wall because of elastic force, its shoulder contacts with the lower port of loam cake, close the medium that enters from import A and entered loam cake, and enter filter screen inner chamber from the lower filter screen outside through filter opening through the spacer ring through hole along the direction of arrow from runner, space through between impeller and filter screen is down to wheel bottom then, because the effect of MEDIA FLOW, this moment, impeller lifted, in above pushing to, medium upwards through impeller inner chamber (this moment, impeller did not change) from the top through hole by outlet B outflow filter, finish filtering function.
Fig. 3~4 are filter backwash duty, this moment, ball valve was in opening, because the flow resistance of ball valve is less than the flow resistance (no matter export B this moment is opened or close) of outlet B, filter screen overcomes spring under the effect of medium differential pressure thrust moves down along guide wall, make its shoulder break away from the loam cake lower port, and contact, thereby changed the medium runner that enters from import A with the housing spacer ring, impeller moves down under the effect of pressure medium simultaneously, and contacts the formation movable sealing with the end in the filter screen.MEDIA FLOW enters from import A and enters impeller inner chamber (also flow out through outlet B simultaneously filtered medium is provided) along arrow from upper filter screen.Because impeller nozzle and filter screen radial shape are at an angle, its recoil effect makes impeller rotate with a fixed angular speed, produces at a high speed radially MEDIA FLOW simultaneously, with 360 ° of endless form from filter screen inner chamber back flush filter screen, impurity is come off from filter screen, finish washing capacity.In the short time of flushing process, as close outlet B, effect can be better.
The present invention can operate automatically in annexes such as ball valve place configuration driven device realization timing or level pressure difference.