JPH11347329A - Filter element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the capability of catching foreign matter by increasing the number of filtration faces while satisfactorily preventing adhesion between neighboring filtration faces formed by folding a filter into bellows. SOLUTION: A filter material 2 is folded to form large filtration faces 5 with the longest length in the radius direction, middle filtration faces 6 with the second longest length, and small filtration faces 7 with the shortest length and both ends of the filter material 2 are joined to give a cylindrical body 8. The intervals of the neighboring large filtration faces 5 become wider in the outer circumferential side than in the inner circumferential side and the middle filtration faces 6 and the small filtration faces 7 are installed in the outer circumferential sides of the intervals of the neighboring large filtration faces 5. Consequently, the filtration surface area is widened. Moreover, the small filtration faces 7 with the shortest length in the radius direction tend to expand in the opening direction due to the stiffness and the pressure in the opening direction is absorbed by deformation of the middle filtration faces 6 with the second strongest stiffness. As a result, close adhesion of all of the large, the middle, and the small filtration faces 5, 6, 7 can be prevented and the filter material can efficiently catch foreign substances contained in a fluid for a long duration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a filter element.

[0002]

2. Description of the Related Art Conventionally, as a filter element incorporated in a filtering device, there is a filter element 50 as shown in FIG. The filter element 50 is formed in a cylindrical shape by joining both ends of a band-shaped filter medium 53 in which a number of folds 51 and 52 are bent in a bellows shape, and a donut-shaped end plate (not shown) is provided at both ends. A tube (not shown) formed by a steel plate having a plurality of holes and being fixed to the inner peripheral surface is fitted. In order to increase the filtration area with the same size, a large number of folds 51 and 52 are formed and folds 5 and 52 are formed.
The number of filtration surfaces 54 between 1, 52 is increased as much as possible,
Thereby, the effect of capturing foreign matter contained in the fluid is improved. In this case, the interval between the inner folds 52 is narrower than the interval between the outer folds 51, so that there is a limit to increasing the number of filter surfaces 54.

For this reason, as described in Japanese Utility Model Publication No. 2-9851 and Japanese Utility Model Publication No. 2-15548,
Various filter elements have been proposed in which the method of folding is improved so that the density of the filter medium does not significantly change between the inner peripheral side and the outer peripheral side of the cylindrical space.

The example shown in FIG. 4 is also proposed from a similar viewpoint. That is, the filter element 55 shown in FIG. 4 focuses on the fact that the interval between the outer folds 51 is wider than the interval between the inner folds 52, Are alternately arranged to fill the space on the outer peripheral side with the short filtration surface 56 and increase the overall filtration area. Such a method of folding the filter element 55 is a method of arranging a large number of M characters radially, and is referred to as an M-fold.

[0005]

However, since the stiffness of the filtering surfaces 54 and 56 is necessarily stronger when the length in the radial direction is shorter, the shorter filtering surface 56 is used as the longer filtering surface. Press 54. As a result, the adjacent longer filtration surfaces 54 come into close contact with each other, and the fluid to be filtered cannot pass therethrough. That is, the entire surface of the filter medium 53 cannot be effectively used, and the filtration area may be reduced.

[0006]

According to the first aspect of the present invention,
A filter element having a large number of filtration surfaces formed by bending a sheet-shaped filter medium into a bellows shape with a large number of folds, and holding both ends of a cylindrical body formed by joining both ends of the filter medium with an end plate, The filtering surface has a large filtering surface bent on a circumference having a radius substantially equal to the inner diameter of the cylindrical body and a circumference having a radius substantially equal to the outer diameter of the cylindrical body. A medium filtration surface bent on a circumference having a radius larger than the circumference and a circumference having a radius substantially equal to the outer diameter of the cylindrical body, and on a circumference having a radius larger than the inner circumference of the medium filtration surface; The small filtration surface is provided separately from a small filtration surface bent on a circumference having a radius substantially equal to the outer diameter of the cylindrical body, and the medium filtration surface and the small filtration surface are located at predetermined positions in a state where they are continuous with each other. And between the large filtering surfaces adjacent to each other.

Therefore, the interval between adjacent large filtration surfaces is wider on the outer peripheral side than on the inner peripheral side, but the medium filtration surface and the small filtration surface are arranged on the outer peripheral side of the space between the adjacent large filtration surfaces. Therefore, the filtration area can be increased. Also,
The small filtration surface with the shortest radial length shows the effect of trying to spread in the direction of the legs with the strength of the waist, but the pressure in the direction of the legs is absorbed by the deformation of the second strongest medium filtration surface In addition, the medium filtration surface is stiffer than the large filtration surface, so that it is not crushed. Thereby, all the large, medium, and small filtration surfaces do not adhere to each other.

According to a second aspect of the present invention, in the first aspect of the present invention, the medium filtration surface and the small filtration surface are disposed one by one between the adjacent large filtration surfaces and disposed at the shortest distance. A plurality of large filtration surfaces are continuously arranged between the medium filtration surfaces and between the small filtration surfaces.

Therefore, it is possible to increase the ratio of the number of the large filtration surfaces to the total filtration surface, and it is possible to further increase the filtration area.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the filter element 1 includes a sheet-shaped
4 has a large number of filtration surfaces 5, 6, 7 formed by bending in a bellows shape, and the both ends of a cylindrical body 8 formed by joining both ends of the filter medium 2 are clamped by end plates (not shown). This is the configuration.

In the present embodiment, the filtering surface is provided as a large filtering surface 5, a medium filtering surface 6, and a small filtering surface 7. The large filtration surface 5 is bent on the circumference of a radius R1 substantially equal to the inner diameter of the cylindrical body 8 and on the circumference of a radius R4 substantially equal to the outer diameter of the cylindrical body 8, and thus has a radial length. Longest. The medium filtration surface 6 has a radius R2 larger than the radius R1 and a radius R2.
4 on the circumference. The small filtration surface 7 has a radius R
Since it is bent on the circumference of radius R3 larger than 2 and on the circumference of radius R4, the length in the radial direction is the shortest.

The filter surfaces 5, 6, 7 having different lengths are
When viewed in a unit having a shape that opens in a V-shape toward the outer periphery, the filter element 1 according to the present embodiment includes two continuous large filtering surfaces 5, one medium filtering surface 6, and one small filtering surface. 7 is formed as one continuous pattern P, and this pattern P is arranged on the circumference of a plurality of patterns.

One pattern P is shown in FIG. FIG.
Is shown in a state where the filtering surfaces 5, 6, 7 are arranged in a direction orthogonal to the radius of the cylindrical body 8, so that the filtering surfaces 5, 6, 7 are arranged along an arc as shown in FIG. Although the state is different from the state shown above, the interval between the fold 3 that becomes the valley of the large filtration surface 5 and the fold 4 that becomes the peak is determined to be the largest W1, and the fold 3 that becomes the valley of the middle filtration surface 6 and the fold 4 that becomes the peak Is set to W2 smaller than W1, and the interval between the fold 3 serving as a valley and the fold 4 serving as a peak of the small filtration surface 7 is the smallest W3.
Stipulated.

Such a filter element 1 is incorporated in a filtering device (not shown),
By passing the fluid from the outside (or inside) to the inside (or outside), foreign matter contained in the fluid is captured.

In this case, the interval between the adjacent large filtration surfaces 5 between the patterns P is wider on the outer peripheral side than on the inner peripheral side. Since the filter surface 7 is provided, the filter area can be increased. Further, the small filtering surface 7 having the shortest radial length has an effect of trying to spread in the leg opening direction with the strength of the waist, but the pressure in the opening direction is the second strongest medium filtering surface 6. And the medium filtration surface 6 is stronger than the large filtration surface 5 and is not crushed. Thereby, all the large, medium, and small filtration surfaces 5, 6, 7 do not adhere to each other. Therefore, foreign substances contained in the fluid can be effectively captured.

The medium filtration surfaces 6 and the small filtration surfaces 7 are disposed one by one between the large filtration surfaces 5 adjacent to each other between the patterns P, and are formed between the medium filtration surfaces 6 disposed at the shortest distance. A plurality of (two in the present embodiment) large filtration surfaces 5 are continuously arranged between the spaces and between the small filtration surfaces 7. In other words, two large filtration surfaces 5 and one medium filtration surface 6 and one small filtration surface 7 respectively.
Thus, since one pattern P is formed, the ratio of the number of large filtering surfaces 5 to the total number of filtering surfaces 5, 6, 7 can be increased. Thereby, the filtration area can be further increased.

In the present embodiment, the ratio of the large filtration surface 5, the medium filtration surface 6, and the small filtration surface 7 is 2: 1: 1.
By increasing the ratio of the large filtration surface 5 to 3: 1: 1 or 4: 1: 1, the filtration area can be further increased. Of course, the middle filtration surface 6 may be provided on both sides of the small filtration surface 7.

[0018]

According to the first aspect of the present invention, there is provided a cylinder having a large number of filtration surfaces formed by bending a sheet-like filter material into a bellows shape with a large number of folds, and joining both ends of the filter material. In a filter element having both ends of a body sandwiched by end plates, the filtering surface is bent on a circumference having a radius substantially equal to the inner diameter of the cylindrical body and a circumference having a radius substantially equal to the outer diameter of the cylindrical body. A large filtration surface, a medium filtration surface bent on a circumference having a radius larger than the inner circumference of the large filtration surface, and a circumference having a radius substantially equal to the outer diameter of the cylindrical body; A small filtration surface which is bent on a circumference having a radius larger than the inner circumference of the surface and a circumference having a radius substantially equal to the outer diameter of the cylindrical body, and the medium filtration surface and the small filtration surface are provided separately. The surface is the large filtration surface adjacent at a predetermined position in a continuous state with each other , So that the interval between adjacent large filtration surfaces is wider on the outer periphery than the inner periphery, but the medium filtration surface and the small filtration surface are arranged on the outer periphery of the adjacent large filtration surface. Therefore, the filtration area can be increased. In addition, the small filtration surface with the shortest radial length shows the effect of trying to spread in the leg opening direction with the strength of the waist, but the pressure in the opening direction is the second strongest deformation of the medium filtration surface. And the medium filtration surface is stiffer than the large filtration surface, so that it is not crushed. Thereby, all the large, medium, and small filtration surfaces do not adhere to each other, and foreign substances contained in the fluid can be effectively captured for a long period of time. Furthermore, since the filtration area with respect to the volume can be increased, a compact filter element can be provided if a filtration area equivalent to the conventional one is required.

According to a second aspect of the present invention, in the first aspect of the present invention, the medium filtration surface and the small filtration surface are disposed one by one between the adjacent large filtration surfaces and disposed at the shortest distance. Since a plurality of large filtration surfaces are continuously arranged between the medium filtration surfaces and between the small filtration surfaces, the ratio of the number of the large filtration surfaces to the total filtration surfaces can be increased, Thereby, the filtration area can be further increased.

[Brief description of the drawings]

FIG. 1 is a plan view showing a bent state of a filter medium of a filter element according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an arrangement pattern of a large filtration surface, a medium filtration surface, and a small filtration surface.

FIG. 3 is a plan view showing a bent state of a filter medium of a filter element in a first conventional example.

FIG. 4 is a plan view showing a bent state of a filter medium of a filter element in a second conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filter element 2 Filter medium 3, 4 fold 5 Large filtration surface 6 Medium filtration surface 7 Small filtration surface 8 Cylindrical body

Claims (2)

[Claims] 1. A filter having a plurality of filter surfaces formed by bending a sheet-like filter material into a bellows shape with a number of folds, and holding both ends of a cylindrical body formed by joining both ends of the filter material with an end plate. In the filter element, the filtering surface is a large filtering surface bent on a circumference having a radius substantially equal to the inner diameter of the cylindrical body and a circumference having a radius substantially equal to the outer diameter of the cylindrical body. A medium filtration surface bent on a circumference having a radius larger than the inner circumference of the large filtration surface and a circumference having a radius substantially equal to the outer diameter of the cylindrical body, and a radius larger than the inner circumference of the medium filtration surface And a small filtration surface bent on the circumference having a radius substantially equal to the outer diameter of the cylindrical body, and the medium filtration surface and the small filtration surface are connected to each other. Being disposed between the large filtration surfaces adjacent to each other at a predetermined position in the state Filter elements and features. 2. The medium filtration surface and the small filtration surface are disposed one by one between the adjacent large filtration surfaces, and between the medium filtration surfaces and the small filtration surfaces disposed at the shortest distance. The filter element according to claim 1, wherein a plurality of large filtration surfaces are continuously arranged.