Suction apparatus for fabric filter and filtering device for liquid filtration using the same

1. A suction apparatus for a fabric filter, comprising:

a suction plate ( 100 ) having a main suction slit ( 110 ) having a length greater than a width and at least one sub-suction slit ( 130 ) located adjacent to a longitudinal side of the main suction slit in a parallel direction and separated from the main suction slit ( 110 ) by a first partition ( 120 a ), the first partition extending the length of the main suction slit in a parallel direction and spacing a longitudinal side of the at least one sub-suction slit away from the longitudinal side of the main suction slit, a width of the sub-suction slit ( 130 ) being smaller than that of the main suction slit ( 110 ), wherein a second partition is formed by a stepped surface of the suction plate at an opposite longitudinal side of the sub-suction slit, the second partition extending the length of the sub-suction slit in a parallel direction, and wherein the width of the main suction slit is uniform along the longitudinal direction and the width of the sub-suction slit is uniform along the longitudinal direction; and

a suction body ( 200 ) on which the suction plate ( 100 ) is mounted.

2. The suction apparatus according to claim 1 , wherein the suction plate ( 100 , 100 ′, 100 ″) is formed by injection molding.

3. The suction apparatus according to claim 1 , wherein the at least one sub-suction slit comprises two to five sub-suction slits ( 130 ) that are formed so as to be parallel to each other.

4. A filtering device, which carries out filtration during back-washing comprising at least one suction apparatus ( 1000 ) as recited in claim 1 ,

the filtering device comprising:

at least one filter that has a plurality of pile threads (F) on a surface thereof which is in direct contact with liquid to be filtrated and is installed for filtration,

wherein the suction apparatus ( 1000 ) is configured so that the suction plate ( 100 ) which includes at least one sub-suction slit ( 130 ) separated in parallel from a main suction slit ( 110 ) by a partition, a width of the sub-suction slit being smaller than that of the main suction slit, is provided so as to face the surface of the filter, the suction apparatus and filter surface being relatively moveable, so that the pile threads (F) undergo delayed straightening and fluctuation by liquid flowing from outside the sub-suction slit to inside the sub-suction slit ( 130 ) and then are rapidly straightened by liquid moving through the main suction slit ( 110 ), during relative movement of the filter surface with respect to the suction plate.

5. The filtering device according to claim 4 , wherein the filter is a disk-shaped filter or a drum-shaped filter.

6. The filtering device according to claim 4 , wherein the suction apparatus ( 1000 ) is installed on each filter.

7. The filtering device according to claim 4 , wherein the suction apparatus ( 1000 ) is installed so as to be movable between the filters.

8. A suction apparatus for a fabric filter, comprising:

a suction plate ( 100 ″) having a main suction slit ( 110 ), at least one sub-suction slit ( 130 ), a first partition and a second partition, wherein the main suction slit and the sub-suction slit are partitioned with the first partition ( 160 ) made of a metal material, wherein the second partition is formed by a stepped surface of the suction plate and configured so that straightening of pile threads during filtration in a filtering device is delayed by suctioning liquid passing through the sub-section slit while the pile threads pass over the first and second partitions, and wherein a width of the sub-suction slit ( 130 ) being smaller than that of the main suction slit ( 110 ); and

a suction body ( 200 ) on which the suction plate ( 100 ″) is mounted.

9. The suction apparatus according to claim 8 , wherein the partition ( 160 ) has a stretched omega shape, and includes flanges ( 161 ) welded to inner walls of the suction body ( 200 ).

10. A suction apparatus for a fabric filter, comprising:

a suction plate forming a planar member with a predetermined thickness, the suction plate ( 100 ′) having a main suction guide ( 140 ) and at least one sub-suction guide ( 150 ), which are spaced apart from each other by a predetermined distance and protrude from a surface of the suction plate so as to extend in one direction;

a suction body ( 200 ) on which the suction plate ( 100 ′) is mounted; and

wherein the at least one sub-suction guide comprises two to five sub-suction guides ( 150 ) that are formed so as to be parallel to each other.