JP2000246020A - Filter unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter unit not marring deep filtering effect, having large filtering capacity, capable of filtering contaminant particles with various particle sizes highly accurately and reduced in pressure loss. SOLUTION: A filter unit is equipped with a filter container 2 having an inflow port 3 of a fluid to be treated and a discharge port 4 of a filtered fluid, the filter material 5, which has a porous elastomer freely stretchable in the direction vertical to the passing direction of the fluid to be treated, housed in the filter container 2, the support member 7 provided to the filter material 5 and the means 8 for driving the support member 7 and expanding and contracting the filter material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter unit for removing contaminant particles in a fluid, and more particularly to a filter unit having a large filtration capacity and high accuracy without impairing the effect of deep filtration.

[0002]

2. Description of the Related Art In recent years, with the diversification of lifestyles, a bathing apparatus that purifies and uses bath water while circulating it has attracted attention. However, bath water contains a wide range of contaminant particles ranging from relatively large stains such as hair and skin fragments to microscopic stains such as bacteria and sebum. It is necessary to select a small pore size filter medium according to the minimum diameter of the particle size distribution of the particles.Since the filter medium is clogged in a short period of time and the pressure loss increases, it is necessary to frequently wash or replace the filter medium. Since long-term use is extremely difficult, a complicated and expensive purification device for decomposing and purifying by using microorganisms is generally used, and a low-cost filtration device with a simple structure has been desired.

[0003] Therefore, various filter units have been studied in which a filter medium is unitized, contaminant particles in a fluid are physically removed, and the contaminant particles are removed by washing.

For example, Japanese Patent Application Laid-Open No. 63-258609 (hereinafter referred to as “A”) discloses a method in which a porous elastic filter material is used as a filter material, which is filtered in an uncompressed state and extruded in a compressed state. A method of cleaning is disclosed.

Japanese Patent Application Laid-Open No. 9-14763 (hereinafter referred to as “B”) discloses that “in the case of filtration in a compressed state, a filter medium having an apparent small pore diameter by compressing in the same direction as the flow of fluid. A filter unit that captures contaminant particles, releases contaminant particles captured in an uncompressed state, and performs washing and regeneration ”is disclosed.

Japanese Unexamined Patent Publication No. Hei 9-506821 (hereinafter referred to as Japanese Patent Application Publication No. Hei 9-506821) discloses, as a filter medium to be filtered in the same compressed state as that of the above Japanese Patent Application Publication No. Hei 9-506821, "a laminate of a plurality of filter elements having different porosity. Is disclosed.

[0007]

However, the above-described conventional filter unit has the following problems.

[0008] The filter unit described in JP-A No. 1 has the following advantages: 1) a large amount of contaminant particles can be trapped by deep-layer filtration, and a large filtration capacity can be expected; however, the average pore size of the filter medium depends on the flow direction of the fluid. And the relatively large particles among the contaminated particles having a size within the pore size distribution range reach the deep part of the filter medium, so that it is difficult to remove the particles by washing, and the filtration performance cannot be sufficiently recovered. Had.

2) If the contaminant particles to be removed have a wide particle size distribution, it is necessary to select the pore size of the filter medium according to the minimum size of the contaminant particles. Therefore, it is necessary to use a filter medium having a small pore size throughout the layer. Therefore, there is a problem that resistance when the fluid passes through the filter medium at the time of filtration increases.

[0010] The filter units described in B and C have the following features: 3) Since the pores in the filter medium are uniformly reduced in size by compression, the filter capacity is increased by large contaminant particles trapped near the surface layer of the filter medium. However, there is a problem in that

4) Since the compression member for compressing the filter medium is formed by a perforated disk, the area of the filter medium with which the fluid to be treated comes into contact is reduced, which is not suitable for filtering a large amount of fluid to be treated. Had.

5) Since the filter is compressed while being filtered in the passage direction of the fluid to be treated, the thickness of the filter medium through which the fluid to be treated passes becomes thin, and the effect of deep filtration is reduced.

[0013] Further, the filter unit described in Japanese Patent Application Laid-Open Publication No. C-3] has the following characteristics. 6) In each filter element, filtration is performed on the surface layer in the same manner as described above. However, there is a problem that many layers of filter elements having different pore diameters must be laminated.

7) When compressing a stack of filter elements each having a different porosity, there is a problem in that the most flexible filter element is compressed the most because the mechanical elasticity of each filter element is different. Was.

8) When the compression ratio at the time of lamination is not enough compression to compress all of the unit filter media of each layer, only the filter element of the first layer having a contact surface with the compression means or the compression member is provided. , The compression force is not transmitted to the deep portion after the second layer, and the size of the pore diameters in the filter elements of the first layer and the second and subsequent layers are reversed.

The present invention solves the above-mentioned conventional problems, and can contaminate particles having a large filtration capacity and various particle sizes with high precision without impairing the effect of deep filtration. An object of the present invention is to provide a filter unit with low loss.

[0017]

In order to solve the above-mentioned problems, a filter unit according to the present invention is provided with a filtration container provided with an inlet for a fluid to be treated and a discharge outlet for a filtration fluid, and is housed inside the filtration container. A filter medium having a porous elastic body that can expand and contract in the direction perpendicular to the passage direction of the fluid to be processed, a support member disposed on the filter medium, and an expansion and contraction unit that drives the support member and expands and contracts the filter medium, Is provided.

Thus, when the porous elastic filter medium is compressed, the compressive force is transmitted to the entire filter medium, and the filter medium does not become thin in the passage direction of the fluid to be treated, so that the deep filtration effect of the filter medium is not impaired. In addition, the pore size can be uniformly reduced over the entire filter medium.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A filter unit according to a first aspect of the present invention is a filter container having an inlet for a fluid to be treated and an outlet for a filtered fluid; A filter medium having a porous elastic body capable of expanding and contracting in the direction perpendicular to the direction in which the filter medium passes, a support member disposed on the filter medium, and an expansion and contraction unit that drives the support member and expands and contracts the filter medium. It has a configuration.

With this configuration, the filter medium can be compressed by the expansion and contraction means during filtration to make the pore diameter in the filter medium fine, and the pore diameter can be enlarged during non-filtration, so that a filter unit with high washing efficiency can be obtained. In addition, since the filter medium can expand and contract in the direction perpendicular to the direction of passage of the fluid to be treated, the filter medium does not become thin in the direction of passage of the fluid to be treated even during compression. Can be filtered.

By compressing the filter medium at the time of filtration and elongating the filter medium at the time of non-filtration, the washing effect is increased, the deterioration of the filter medium due to mechanical fatigue can be prevented, and unnecessary performance deterioration can be prevented.

Here, as the filter medium, a porous elastic body having continuous holes such as a mesh, a sponge, a felt, and a wound filter is used.

The filter medium is formed in a block shape, a hollow cylindrical shape or the like.

As the support member of the expansion / contraction means, a plate-shaped member fixed to the filter medium by bonding or the like, a cap-shaped member covered with the filter medium, or the like is used.

As a means for driving the support member, a cylinder, a spring, a motor, or the like using a fluid pressure such as air pressure or hydraulic pressure is used. In addition, a magnet is buried in the support member and an electromagnetic wave is provided outside the filtration container. It is also possible to expand and contract the filter medium in a non-contact manner by a coil. Further, it is also possible to drive with a temperature difference using a shape memory alloy spring.

The compression of the filter medium requires sufficient compression in order for stress to be distributed throughout the inside of the filter medium. However, in order to capture a large amount of contaminant particles in the filter medium, the compression of the contaminant particles inside the filter medium is required. It is preferable that the pores do not disappear, and the compression ratio (%)
= [(Filter material volume at non-compression-filter media volume at compression) / filter material volume at non-compression] x 100
It is preferably at most 5%, more preferably at least 30% and at most 70%.

Here, depending on the size, shape, material, etc. of the filter medium, if the compressibility is smaller than 30%, it becomes difficult not only to sufficiently reduce the pore diameter in the filter medium but also, depending on the material, the supporting member. And a tendency to be in a non-compressed state at the central portion which is furthest from the fixing member, and the compression ratio is 70%.
%, The pore diameter is too small, the resistance at the time of filtration becomes too large, and in the case of a hydrophobic material, water does not easily enter the pores and the compression tends to increase. When the compression ratio is smaller than 10% or larger than 95%, the above tendency is remarkable, and therefore, it is not preferable.

According to a second aspect of the present invention, there is provided a filter unit according to the first aspect, wherein the filter medium is formed by stacking and / or separating a plurality of unit filter media each having a different porosity in the passage direction of the fluid to be treated. It has a configuration that is arranged in the same manner.

With this configuration, by combining unit filter media having substantially the same pore size in each unit filter media and having different pore sizes for each unit filter media, the pore size can be changed in multiple stages along the passage direction of the fluid to be treated. Thus, the pore size distribution of the filter medium can be appropriately configured according to the particle size distribution of the contaminant particles in the fluid to be treated.

According to a third aspect of the present invention, there is provided a filter unit according to the first or second aspect, wherein the filter medium has a concave portion formed on the surface on the inflow side of the fluid to be treated. .

With this structure, in addition to the effect obtained in claim 1 or 2, in addition to the effect obtained in claim 1, on the inflow side surface of the fluid to be treated having the concave portion when the porous elastic filter medium is compressed, the concave portion is generated on the filter medium only by reducing its width. Since the applied stress is small and the stress increases on the outflow side of the fluid to be treated in which the concave portion is not formed, the communication hole of the filter medium can be miniaturized from the inflow side to the outflow side.

Here, the shape of the concave portion is formed in a groove shape, a hole shape or the like. Further, the wall surface in the concave portion is formed in a slanted shape, a curved shape, a vertical shape, a step shape, or the like with respect to the surface of the filter medium.

For example, when the wall surface inside the concave portion is formed in a slope, the hole diameter can be reduced at a predetermined reduction rate.
When the particle size distribution of the contaminant particles is relatively wide, a gradient of the pore size that matches the particle size distribution can be provided.

When the wall surface is formed in a curved shape, the pore diameter can be reduced while changing the reduction ratio, so that the processing target fluid containing contaminant particles having a particle size distribution centered on a specific particle size can be treated. In particular, it can be suitably used.

When the wall surface is formed in a vertical plane, a large amount of relatively large-diameter contaminant particles can be filtered.

When the wall surface is formed stepwise, the pore diameter can be changed stepwise, so that it can be suitably used when removing several types of contaminant particles having a relatively narrow pore diameter distribution.

According to a fourth aspect of the present invention, there is provided the filter unit according to any one of the first to third aspects, wherein the support member on the outflow side of the fluid to be treated locally compresses the filter medium. Is formed.

With this configuration, in addition to the effects obtained in the first to third aspects, a large compressive force can be applied to the filter medium at the portion where the projection of the support member contacts, regardless of the material and shape of the filter medium. The diameter of the pores in the filter medium can be reduced along the passage direction of the fluid to be treated.

Here, the shape of the convex portion can be formed in a trapezoidal shape, a step shape, a slope shape, a curved shape, or the like.

For example, when formed in a trapezoidal or stepped shape,
Since the pore diameter can be changed stepwise, the width of the particle size distribution for each type of contaminating particles is relatively narrow, but the present invention can be suitably used when various types of contaminating particles are used.

When the wall surface is formed in a slanted shape, the pore diameter in the filter medium can be changed at a predetermined reduction ratio. When the particle size distribution of the contaminant particles is relatively wide, a gradient of the pore size that matches the particle size distribution can be provided.

When the wall surface is formed in a curved shape, the pore diameter can be reduced while changing the reduction ratio, so that the processing target fluid containing contaminant particles having a particle size distribution centered on a specific particle size can be treated. In particular, it can be suitably used.

According to a fifth aspect of the present invention, there is provided a filter unit according to any one of the first to fourth aspects, wherein the porous elastic body contains an organic polymer.

With this configuration, in addition to the effects obtained in claims 1 to 4, the organic polymer can easily obtain the elasticity required for compression, and the pore diameter can be easily controlled, so that the contaminated particles to be removed are removed. The filter unit can be optimized for the particle size of the above.

Here, as organic polymers, synthetic polymers such as polyolefins such as polyethylene, polypropylene and polystyrene, polyurethanes, natural rubbers, rubbers such as butadiene and silicone, polytetrafluoroethylene, polyvinyl alcohol, polyamino acids and polylactic acid are used. Molecules or derivatives thereof, polysaccharides such as cellulose and mannose, natural polymers such as polypeptides and derivatives thereof are used. These materials are used alone or in combination.

The above material is more preferably a foam, and more preferably a foam having 10 to 90 holes per inch.

Here, as the number of pores becomes smaller than 10, the cells do not become fine-diameter open cells, so that there is a tendency that contaminant particles having a fine particle diameter cannot be trapped. This is not preferable because the resistance increases significantly.

According to a sixth aspect of the present invention, there is provided a filter unit according to any one of the first to fifth aspects, wherein the filter medium is formed in a hollow cylindrical shape, and is covered from the outer peripheral side to the inner peripheral side of the filter medium. It has a configuration through which the processing fluid passes.

With this configuration, the surface area on the outer peripheral side is large, and the filtering capacity per unit volume of the filter medium is increased.
A large amount of the fluid to be treated can be processed, and the entire filter unit can be relatively reduced in size.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(Embodiment 1) FIG. 1 (a) is a cross-sectional view showing a state of a filter unit in Embodiment 1 of the present invention at the time of non-filtration, and FIG. 1 (b) shows a state at the time of filtration. FIG.

1 (a) and 1 (b), reference numeral 1 denotes a filter unit, 2 denotes a substantially cylindrical filtration container, 3 denotes an inlet for a fluid to be treated disposed on the side of the filtration container 2, and 4 denotes a filter. An outlet for the filtered fluid, which is disposed substantially at the center of the bottom surface of the container 2,
5 is a substantially cylindrical filter medium formed of a porous elastic body having continuous holes having 10 to 90 holes per inch, and 5a is a groove having a substantially equilateral triangular cross section in the circumferential direction of the outer peripheral surface of the filter medium 5. A fixing member for fixing the bottom surface of the substantially cylindrical filter medium 5 to the inside of the filtration container 2; a support member 7 adhered to the upper surface of the filter medium 5 to expand and contract the filter medium 5; Is extended and retracted to expand and contract the filter medium 5.
And a rod section for connecting the expansion and contraction means 8.

The operation of the filter unit according to the first embodiment configured as described above will be described below.

As shown in FIG. 1A, when the fluid to be treated is not filtered, the rod portion 8a is contracted, and the filter medium 5 is extended.

At the time of filtration, as shown in FIG.
The rod portion 8a extends from the expansion and contraction means 8, and the filter medium 5 is compressed. The fluid to be treated introduced from the inlet 3 flows from the outer peripheral surface side to the inner peripheral surface side of the substantially cylindrical filter medium 5, and the filter medium 5
It is filtered out and discharged from the outlet 4. The bottom of the filter medium 5 is fixed to the bottom of the filter container 2 by a fixing member 6, and the filtered fluid that has passed through the filter medium 5 and the fluid that has not passed through do not mix in the filter container 2.

Here, as the filter medium 5 is compressed, the width of the recess 5a on the outer peripheral surface of the filter medium 5 becomes narrower.
Since the compressive force from the supporting member 7 does not propagate to the filter medium 5 around the point a, the stress of the filter medium 5 is low and the compressibility of the pore diameter is low. The compressive force is large and the stress is large in the deep part on the filtered water discharge side near the center axis of the filter medium 5, and the stress increases from the surface to the deep part. As a result, continuous pores are formed from the surface of the filter medium 5 to the deep layer. Is reduced in size.

In the present embodiment, the filter medium 5 is formed in a substantially cylindrical shape, and the fluid to be treated flows in from the outer peripheral surface of the filter medium 5, and the filtered fluid that has been purified while passing through the inside of the filter medium 5 is used as the filter medium 5. Although the filter medium 5 is configured to flow out from the inner peripheral surface into the internal space, the filter medium 5 may be formed in a hollow polygonal cylindrical shape or the like. The substantially cylindrical filter medium 5 and the space inside the filter medium 5 are arranged coaxially with the center axis of the filtration container 2 and coaxially with the filtration fluid discharge port 4, but are not particularly limited.

The gap between the filter medium 5 and the filter container 2, the filtration fluid passage inside the filter medium 5, the resistance received when passing through the outlet 4 and the inlet 3, and the resistance received when the filtered fluid passes through the outlet 4. However, it is preferable to reduce the resistance of the fluid to be treated when compressing and filtering the filter medium 5.

The support member 7 is formed in the same shape as the upper surface of the filter medium 5, but there is no particular limitation on the shape. The movable member of the support member 7 is large enough to move in the filter vessel 2. The surface of the fluid to be treated, which has a surface area equal to or larger than that of the discharge port 4 or the inlet 3, so as to sufficiently cover the surface to be compressed and not to obstruct the flow of the fluid to be treated in the filtration vessel 2. The position is not limited to the arrangement where the filter medium 5 is compressed from above.

As the driving means constituting the expansion / contraction means 8, a spring or the like may be used, or a cylinder using a fluid pressure such as air or oil may be used.

The filtering container 2 may be divided into a lid and a housing, and the expansion / contraction means 8 may be integrated with either one.
The filter medium 5 may be provided in the filtration container 2 and can be compressed and fixed with the lid closed. Filter media 5
A non-contact type in which a magnet is buried in the contact portion and an electromagnetic coil is disposed outside the filtration container 2 may be used, and an electric mechanism such as a motor may be used.

Further, a stopper for limiting the moving width of the support member 7 may be provided on the inner surface of the filtration container 2 or the inner space of the filter medium 5, or the expansion / contraction means 8, the rod portion 8a, etc., so that the expansion / contraction rate of the filter medium 5 is constant. Thereby, the filtering performance of the filter medium 5 can be constantly maintained.

(Embodiment 2) FIG. 2 (a) is a cross-sectional view showing a non-filtration state of a filter unit in Embodiment 2 of the present invention, and FIG. 2 (b) is a cross-sectional view at the time of filtration. is there.

2 (a) and 2 (b), reference numeral 1 'denotes a filter unit according to the second embodiment, 5' denotes a substantially cylindrical filter medium, and 6 'denotes a bottom surface of the substantially cylindrical filter medium 5'. A fixing member 7 'is provided on the lower surface of the filter medium 5' to support the filter medium 5 '. The fixing members 9 and 10 are in contact with the fixing member 6' and the filter medium 5 'of the support member 7', respectively. It is a substantially circular trapezoidal convex portion formed in the portion.

2 is a filtration container, 3 is an inlet for the fluid to be treated,
Reference numeral 4 denotes a discharge port for the filtered fluid, 8 denotes expansion / contraction means, and 8a denotes a rod portion, which are the same as those in the first embodiment.

The second embodiment is different from the first embodiment in that the filter medium 5 ′ is a cylindrical foam and has no concave portion on the surface, and a fixing member for fixing the filter medium 5 ′ to the filtration container 2. 6. The point is that protrusions 9 and 10 are formed on the support member 7 'that expands and contracts the filter medium 5'.

In the present embodiment, the projections 9 and 10 are formed in a trapezoidal shape. However, depending on the type, amount, particle size distribution, etc. of the contaminant particles contained in the fluid to be processed, the projections 9 and 10 may be stepped or sloped. , May be formed in a swollen shape or the like.

The operation of the filter unit according to the second embodiment configured as described above will be described below.

When the filter medium 5 'is compressed by the support member 7' as shown in FIG. 2B, the outer peripheral side of the filter medium 5 'has a low compression ratio,
On the inner peripheral side, the compression ratio is increased by the convex portions 9 and 10 formed on the fixing member 6 ′ and the support member 7 ′, so that the stress in the filter medium 5 ′ increases along the passage direction of the fluid to be treated, and The pore size is reduced.

By appropriately selecting the projections 9 and 10,
The distribution of locally generated stress can be changed, and the pore size distribution and the compressibility distribution can be freely designed.

Since the thickness of the filter medium 5 ′ in the passage direction of the fluid to be treated does not decrease, the filtration can be performed without impairing the effect of the deep filtration.

[0072]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of the present invention will be described below.

(Example 1) Bath water was filtered using the filter unit 1 described in the first embodiment.

A tube was provided in the bathtub, bath water was introduced into the inlet 3 of the filter unit 1 via a water flow pump, and the bath water was circulated from the outlet 4 through the tube into the bathtub.

While driving the water flow pump and filtering the bath water, four adults were asked to remove dirt in the bathtub while taking a bath.
As a result of observing the change in the turbidity of the bath water in the bath tub, the increase in the turbidity of the bath water was suppressed to less than about 10% as compared with the case where no filtration was performed. Also, the pressure loss rise of the filter medium 5 'is 1% or less,
Filtration with high filtration accuracy, large filtration capacity, and low pressure loss was possible.

(Example 2) When the bath water was filtered using the filter unit 1 shown in Embodiment 1, 70% of the turbidity contained in the bath water before the filtration was performed.
Was removed. Further, the increase in pressure loss was 1% or less of the initial pressure loss, and high-precision filtration with low pressure loss was possible.

[0077]

As described above, according to the filter unit of the first aspect of the present invention, a filtration container provided with an inlet for the fluid to be treated and a discharge outlet for the filtration fluid, and the filter container is housed inside the filtration container. A filter medium having a porous elastic body that can expand and contract in the direction perpendicular to the passage direction of the fluid to be treated, a support member disposed on the filter medium, and an expansion and contraction unit that drives the support member and expands and contracts the filter medium. , So that when the filter medium is compressed, it is possible to uniformly apply a compressive force to the entire filter medium, without impairing the effect of deep filtration of the filter medium,
There is an effect that the pore size of the filter medium can be finely changed, and a highly accurate filter unit can be obtained.

According to the filter unit of the second aspect, in the first aspect, the filter medium is obtained by laminating and / or separating a plurality of unit filter media each having a different porosity in the passage direction of the fluid to be treated. Since it is arranged, the pore size can be changed in multiple steps along the passage direction of the fluid to be treated, and the pore size distribution of the filter medium is appropriately configured according to the particle size distribution of the contaminant particles in the fluid to be treated. This has the advantageous effect that it can be performed.

According to the filter unit of the third aspect, in the first or second aspect, the filter medium has a concave portion formed on the surface on the inflow side of the fluid to be treated.
When the porous elastic filter medium is compressed, the width of the concave portion on the surface on the inflow side of the fluid to be treated becomes smaller, but no stress occurs in portions other than the concave portion, and stress is applied to the outflow side of the fluid to be treated where no concave portion is formed. Since it increases, the communication holes of the filter medium are made finer from the inflow side to the outflow side, and even if the particle diameter of the dirt contained in the fluid to be treated has a wide range, the pore diameter in the filter medium is made fine according to the size. And a high-precision filter unit having a large filtration capacity can be obtained.

According to the filter unit of the fourth aspect, in any one of the first to third aspects, the convex member for locally compressing the filter medium is provided on the support member on the outflow side of the fluid to be treated. Since it has a configuration in which it is formed, in addition to the effects obtained in claims 1 to 3, a large compressive force is applied to a portion of the filter medium where the convex portion of the expansion / contraction means contacts regardless of the material or shape of the filter medium. Since it can be provided, the advantageous effect that the pore diameter in the filter medium can be reduced can be obtained.

According to the filter unit of the fifth aspect, in any one of the first to fourth aspects, since the porous elastic body contains an organic polymer, the elasticity required for compression is low. In addition, since the pore size can be easily controlled, the advantageous effect that a filter unit optimal for the particle size of the contaminated particles to be removed can be obtained.

According to a sixth aspect of the present invention, in the filter unit according to any one of the first to fifth aspects, the filter medium is formed in a hollow cylindrical shape, and the filter medium is processed from the outer peripheral side to the inner peripheral side of the filter medium. Since the fluid passes through, the surface area on the outer peripheral side is large, and the filtering capacity per unit volume of the filter medium increases,
An advantageous effect that a large amount of the fluid to be processed can be processed and the entire filter unit can be relatively reduced in size can be obtained.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing a state of a filter unit according to Embodiment 1 of the present invention at the time of non-filtration; FIG.

FIG. 2A is a cross-sectional view illustrating a state of a filter unit according to a second embodiment of the present invention at the time of non-filtration; FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'Filter unit 2 Filtration container 3 Inlet 4 Outlet 5, 5' Filter material 5a Depression 6, 6 'Fixing member 7, 7' Supporting member 8 Telescopic means 8a Rod part 9, 10 Convex part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shigeru Narakino 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 4D019 AA03 BA12 BA13 BB02 BB03 BB07 BD02 BD03 CA03 CB01 CB02

Claims (6)

[Claims] 1. A filtration container provided with an inlet for a fluid to be treated and a discharge outlet for a filtration fluid, and a porous elastic body housed inside the filtration container and capable of expanding and contracting in a direction perpendicular to the passage direction of the fluid to be treated. A filter unit comprising: a filter medium having: a filter member; a support member disposed on the filter medium; and an expansion / contraction device that drives the support member and expands / contracts the filter medium. 2. The filter medium according to claim 1, wherein a plurality of unit filter media each having a different porosity are stacked and / or separated in the direction in which the fluid to be treated passes. Filter unit. 3. The filter medium according to claim 1, wherein the filter medium has a concave portion formed on the surface on the inflow side of the fluid to be treated.
Or the filter unit of 2. 4. The method according to claim 1, wherein a convex portion for locally compressing the filter medium is formed on the support member on the outflow side of the fluid to be treated. Filter unit. 5. The filter unit according to claim 1, wherein the porous elastic body contains an organic polymer. 6. The filter according to claim 1, wherein the filter medium is formed in a hollow cylindrical shape, and the fluid to be processed passes from an outer peripheral side to an inner peripheral side of the filter medium. Filter unit.