Filter component

Abstract

There is a need to reduce the amount of overlapping parts of a nonwoven fabric of a filter component to thereby lengthen the life of the filter component. This need is met by the filter component formed of a cylindrical nonwoven fabric having a center axis, and having a plurality of polygon-shaped cross-sections which are a same shape that are formed side-by-side at predetermined intervals along the center axis. Each side of each of the polygons is formed by a mountain fold part on a plane perpendicular to the center axis, and each vertex of one polygon is connected by a mountain fold part to each vertex of another polygon, respectively.

Claims

1. A filter component formed of a cylindrical nonwoven fabric having a center axis, the filter component comprising: polygon-shaped cross-sections, each of which has a polygon shape formed along the center axis, the polygon shape being formed by only mountain fold parts such that vertexes of the polygon shape are positioned on a plane perpendicular to the center axis, wherein in polygon shapes of the polygon-shaped cross-sections, each vertex of one of the polygon shapes is connected by a mountain fold part to each vertex of another of the polygon shapes, respectively, wherein a valley fold part is formed between adjacent mountain fold parts among the mountain fold parts connecting each vertex of the one of the polygon shapes with each vertex of the another of the polygon shapes, and wherein the valley fold part is formed with an inclination angle not perpendicular with respect to the center axis.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a view illustrating the outer appearance of a filter component of the present invention.

(2) FIG. 2 is a view illustrating a cross-section of the filter component of the present invention.

(3) FIG. 3 is a view illustrating the relation between the outer appearance and cross-sections of the filter component of the present invention.

(4) FIG. 4 is a view illustrating the relation between adjacent cross-sections of the filter component of the present invention.

(5) FIG. 5 is a view illustrating a configuration in which the surface area of a filter component is increased by folding a nonwoven fabric in the circumferential direction.

(6) FIG. 6 is a view illustrating a configuration in which the surface area of a filter component is increased by folding a nonwoven fabric in the longitudinal direction.

(7) FIG. 7 is a view illustrating a configuration in which the surface area of the filter component is increased by folding a nonwoven fabric in the longitudinal direction.

DESCRIPTION OF EMBODIMENTS

Embodiment 1

(8) The invention of the present application will now be described with reference to FIG. 1 to FIG. 4. FIG. 1 is a view that illustrates a filter component of the present invention. FIG. 2 is a cross-sectional view as seen from a direction along a center axis CL in FIG. 1. FIG. 3 is a view illustrating the relation between the outer appearance and cross-sections of the filter component of the present invention. FIG. 4 is a view illustrating the relation between adjacent cross-sections of the filter component of the present invention.

(9) A filter component 10 is a member in which a nonwoven fabric is formed in a cylindrical shape around the center axis. In the filter component 10, m n-gon cross-sectional portions are formed side by side at intervals in the direction along the center axis CL. That is, the filter component 10 is a filter component formed of a cylindrical nonwoven fabric having a center axis, and having a plurality of polygon-shaped cross-sections which are a same shape that are formed side by side at predetermined intervals along the center axis. Here, as a representative example of an embodiment, a case of a generalized n-gon will be described using the example of a hexagon for which n=6.

(10) In each of the n-gon polygons (hexagons), each side is formed by a mountain fold part on a plane perpendicular to the center axis CL. In each cross-section of the plurality of polygons (hexagons), among polygons that are adjacent to each other, each vertex of one polygon is connected by a mountain fold part to each vertex of another polygon. That is, in FIG. 1 and FIG. 2, for example, with respect to a hexagon-shaped cross-section formed by a vertex 11, a vertex 12, a vertex 13, a vertex 14, a vertex 15 and a vertex 16 and a hexagon-shaped cross-section (vertex 17, vertex 18, vertex 19, vertex 20 . . . ) that is adjacent thereto, the vertex 11, vertex 12, vertex 13 . . . vertex 16 of one of the hexagons and the vertex 17, vertex 18, vertex 19, vertex 20 . . . of the hexagon that is adjacent thereto are connected by mountain fold parts 10a. Further, among the adjacent mountain fold parts 10a, valley fold parts 10b are formed between mountain fold parts 10a that are adjacent. Further, at one vertex in the hexagon, for example, at the vertex 11, the mountain fold part 10a and the valley fold part 10b are connected, and the valley fold part 10b is connected to a vertex that neighbors a vertex in an adjoining hexagon which the mountain fold part 10a connects. By this means, the mountain fold parts 10a and the valley fold parts 10b are formed at an inclination with respect to the center axis CL.

(11) Thus, in the filter component 10, by adopting a twisting structure in which the mountain fold parts 10a and the valley fold parts 10b are alternately formed, it can be ensured that vertices of overlapping regions of adjacent filters are not aligned when the filter component 10 is folded in the direction of the center axis CL of the filter component 10. That is, when the filter component 10 is folded in the axial direction of the filter component 10, it can be ensured that among an adjacent overlapping region formed by the vertex 11, the vertex 12 and the vertex 18 and an adjacent overlapping region formed by the vertex 11, the vertex 17 and the vertex 18, the vertex 12 and the vertex 17 are completely not aligned with each other. Accordingly, among adjacent overlapping regions of the filter component 10 when the filter component 10 is folded in the direction of the center axis CL, it can be ensured that only portions of a region Y in FIG. 2 that is a region of one part thereof overlap. The same applies with respect to the other vertices also.

(12) In addition, in the filter component 10 of the invention of the present application, since the mountain fold parts 10a and the valley fold parts 10b are positioned diagonally along the center axis CL, adjacent regions Y are positioned in a rotationally symmetric manner around the center axis CL. Therefore, when the filter component 10 is folded in the axial direction of the center axis CL of the filter component 10, regions that are adjacently overlapping in the axial direction of the center axis CL decrease to the amount of regions Z among the region Y. In this respect, the manner in which the overlapping of folded regions is continuous along the center axis CL as illustrated in FIG. 7 according to the conventional technology is significantly different from the present invention. According to the conventional technology, regions X that are adjacently overlapping in the folded regions always have the same area along the center axis CL, and a region in which the peak of the density of the nonwoven fabric concentrates is formed there. However, in the case of the present application, even if the filter component 10 is folded in the axial direction of the center axis CL of the filter component 10, with respect to the regions that are adjacently overlapping in the axial direction of the center axis CL, the adjacently overlapping regions decrease, for example, as the amount decreases from the amount of the region Y to the amount of the regions Z. Thus, by adopting the configuration of the invention of the present application, even when the filter component 10 is folded in the axial direction of the center axis CL of the filter component 10, regions at which the peak of the density of the nonwoven fabric concentrates are decreased and dispersed.

(13) In the filter component 10, the respective vertices of an n-gon of each cross-section are formed as rows (1, 2, . . . p, . . . n) in which the vertices are side by side in a direction parallel to the center axis CL. A vertex positioned in a row to serve as a reference is taken as a first vertex, and in the direction toward the row located next to the reference row until an n-th row, the respective vertices form rows (1, 2, . . . p, . . . n) in which the vertices are arranged side by side in a direction along the center axis CL.

(14) As illustrated in FIG. 3 and FIG. 4, in this case, when an arbitrary row is taken as a q-th row, each vertex of a p-th (arbitrary natural number within a range of 1 to m inclusive) n-gon is denoted as i.sub.p,q (p=value in a range from 1 to m inclusive, q=value in a range from 1 to n inclusive). In FIG. 3 and FIG. 4, for example, at a first cross-section, the vertices are i.sub.1,1, i.sub.1,2, i.sub.1,3, . . . , i.sub.1,q, . . . , i.sub.1,n-1, and i.sub.1,n. In the case of a hexagon, the vertices are i.sub.1,1, i.sub.1,2, i.sub.1,3, i.sub.1,4, i.sub.1,5 and i.sub.1,6. At an arbitrary p-th cross-section, the vertices are i.sub.p,1, i.sub.p,2, i.sub.p,3, . . . i.sub.p,q, . . . i.sub.p,n-1 and i.sub.p,n. In the case of a hexagon, the vertices are i.sub.p,1, i.sub.p,2, i.sub.p,3, i.sub.p,4, i.sub.p,5 and i.sub.p,6. At the m-th cross-section at the other end, the vertices are i.sub.m,1, i.sub.m,2, i.sub.m,3, . . . i.sub.m,q, . . . i.sub.m,n-1, and i.sub.m,n. In the case of a hexagon, the vertices are i.sub.m,1, i.sub.m,2, i.sub.m,3, i.sub.m,4, i.sub.m,5 and i.sub.m,6.

(15) The filter component 10 has a twisting structure between the cross-sections. That is, the mountain fold parts 10a are formed between an arbitrary cross-section and another cross-section adjacent thereto in a manner so that the respective vertices are twisted and shifted around the center axis CL with each other. Further, the valley fold parts 10b are formed between the mountain fold parts 10a. By this means, as described above, the mountain fold parts 10a and the valley fold parts 10b are formed at an inclination with respect to the center axis CL.

(16) The filter component 10 has a twisting structure configured so as to have mountain fold parts that join a vertex i.sub.p,q in a cross-sectional portion of a p-th n-gon and a vertex in i.sub.p-1,q-1 a cross-sectional portion of the p-1-th n-gon. As illustrated in FIG. 4, at arbitrary cross-sections that are adjacent, the filter component 10 has mountain fold parts provided so that i.sub.m,1 is joined with i.sub.m-1,n, i.sub.m,2 is joined with i.sub.m-1,1, i.sub.m,3 is joined with i.sub.m-1,2, an arbitrary vertex i.sub.m,q is joined with i.sub.m-1,q-1, i.sub.m-1,n-1 is joined with i.sub.m-1,n-2, and i.sub.m,n is joined with i.sub.m-1,n-1. In the case of a hexagon, the filter component 10 has mountain fold parts provided so that i.sub.m,1 is joined with i.sub.m-1,n, i.sub.m,2 is joined with i.sub.m-1,1, i.sub.m,3 is joined with i.sub.m-1,2, an arbitrary vertex i.sub.m,4 is joined with i.sub.m-1,3, i.sub.m,5 is joined with i.sub.m-1,4, and i.sub.m,6 is joined with i.sub.m-1,5. At such time, the amount of twisting of the twisting structure can be arbitrarily decided. The correspondence of the mountain fold parts may be the reverse of that described above.

(17) By adopting this configuration, even if the filter component is folded, the amount of overlapping parts is reduced, and thus the life of the filter component can be lengthened.

REFERENCE SIGNS LIST

(18) 10 filter component 10a mountain fold part 10b valley fold part 50 conventional filter component