JP3950766B2 - Filter cartridge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a filter cartridge suitable disposable type for filtering liquid. More specifically, the present invention relates to an amine-based organic stripping solution used for a substrate for manufacturing electronic components such as a semiconductor wafer or a glass substrate for manufacturing a liquid crystal device, and a pigment dispersion photo used for a glass substrate for manufacturing a liquid crystal device. resist, slurry used in chemical mechanical polishing apparatus, such as a liquid used in general industrial, or filtration of the chemical containing a large amount of foaming or vaporizable material, the filter cartridge for performing manufacturing or the like of the pure water Related.
[0002]
[Prior art]
FIG. 5 illustrates a general filter cartridge. A conventional filter cartridge accommodates a filter element 1 having a filtering action in an airtight housing 13 having a manifold (collecting portion) having various outlets. More specifically, the filter cartridge is a cylindrical filter in which a sheet-like filter membrane is folded into a pleated shape with a fixed width many times together with a net-like support, and the ends are joined together to form an endless shape. The material 3, the resin-made inner cylinder 5 having a large number of openings 27 and the outer cylinder 7 having a large number of openings 25 that support the inner and outer peripheral surfaces of the cylindrical filter material 3, and the cylindrical filter material 3 A filter element 1 comprising resin caps 9 and 11 for fusing and sealing the upper and lower ends together with the upper and lower ends of the inner and outer cylinders is accommodated. The filter element may be removably housed in a separate hermetic housing 13 (exchangeable type) or may be integrally joined to the housing at a weld 19 as shown (disposable type). The present invention relates to the latter type of filter cartridge.
[0003]
The housing 13 includes a lid portion 15 and a housing portion 17. The lid 15 may include a primary side gas vent port 35 and a secondary side gas vent port 39 according to the characteristics of the liquid to be filtered. The filter element 1 is inserted into the inside from the upper opening of the housing portion 17 and is covered with the lid portion 15 while being held on the positioning support member 51 . Mating surface 19 of the full I Luther element 1 and is housing portion 17 and the lid portion 15 disposable type may be coupled by welding.
[0004]
The cap 9 at the top of the filter element 1 is provided with an annular wall 41 protruding upward that fits into the cylindrical support wall 45 of the lid portion 15 of the housing 13 and is hermetically held by an O-ring 43. . At the upper end of the lid 15, air bubbles generated when the vaporizable substance dissolved in the liquid is vaporized according to the type and characteristics of the liquid to be filtered are prevented from decreasing the filtration area of the filter material 3. The primary side gas vent port 35 and the secondary side gas vent port 39 may be provided.
[0005]
An inlet 21 for the liquid to be processed is formed at the lower end of the housing. The liquid to be treated flows from the inlet 21, is distributed in an annular primary passage 23 formed between the outer peripheral surface of the filter element 1 and the inner wall of the housing 13, passes through the opening 25 of the outer cylinder 7, and is cylindrical. After being filtered by the filter material 3, it flows into the central secondary passage 29 through the opening 27 of the inner cylinder 5, and flows out as a purified liquid from the secondary outlet 33 at the lower end of the housing. Yes. The solid in the raw material liquid is held on the surface of the filter material 3.
[0006]
As will be apparent to those skilled in the art, various configurations for the filter cartridge are possible, for example, the secondary vent port 39 is configured at the location of the secondary outlet 33 and the secondary outlet is It may be arranged at the location of the secondary vent port. Further, in order to facilitate removal of the liquid to be treated and cleaning of the filter cartridge when the filter element 1 is replaced, a primary side drain port 35 ′ and a secondary side drain port 39 ′ may be provided. Further, in such a configuration, the filter cartridge may be used upside down. In this case, the drain ports 35 ′ and 39 ′ are used as gas vent ports, and the gas vent ports 35 and 39 are used as drain ports. May be.
[0007]
[Problems to be solved by the invention]
Although depending on the pressure of the inflowing liquid and the characteristics of the filter material to be used, a relatively strong pressure toward the center is applied to the filter material 3 of the filter cartridge during use. Therefore, the cylindrical members 5 and 7, particularly the downstream cylindrical member (in the case of FIG. 5, the inner cylinder 5), need to be formed in a relatively rigid structure in order to hold the filter material in place. There is.
[0008]
However, when the downstream cylindrical member 5 is formed in a highly rigid structure, the filter element 1 thermally expands, particularly when used for filtration of a high-temperature liquid, and the upper and lower ends of the cylindrical member and the resin cap 9 , 11 has a drawback in that stress is generated in the fusion sealed portion and the filter element 1 is deformed, and in an extreme case, stress cracking occurs in the cylindrical portion and the fusion sealed portion.
[0009]
That is, for example, when the liquid to be filtered has 100 to 180 ° C., the filter material 3 and the cylindrical members 5 and 7 are heated to the same temperature as the liquid by heat conduction. However, since the housing 13 itself is in contact with the surrounding environment, the temperature rise is smaller than that of the cylindrical member. As a result, a thermal stress is generated between the filter element 1 and the housing 13.
[0010]
The filter material itself is usually made of a thin membrane and the upstream cylinder (in the case of FIG. 5, the outer cylinder 7) also does not need to support the filtration pressure, so it has a relatively flexible structure, or Since it can be formed into a thin wall, no particular problem arises even when thermal stress is applied. However, as described above, the downstream cylinder (inner cylinder 5 in the case of FIG. 5) is manufactured with a highly rigid structure in order to support the pressure during filtration, and therefore a relatively large thermal stress is applied. In particular, local stress concentrates on the fusion-sealed portion between the inner cylinder 5 and the resin caps 9 and 11, causing deformation of the member and, in an extreme case, cracking, thereby impairing the function as a filter element. Sometimes.
[0011]
As one method for dealing with the thermal stress caused by such a temperature difference between the filter element 1 and the housing 13, in the prior art, one end (the upper end in FIG. 1) of the filter element 1 is completely fixed. Instead, a method is known in which the O-ring 43 is used so as to be slidable in the lid portion 15 while maintaining a sealed state. However, this configuration usually has drawbacks relating to durability, chemical resistance, reliability of the sealed state, etc. associated with the use of an O-ring formed from an elastic body such as rubber. As can be seen from FIG. 5, the O-ring 43 is rubbed against the inner wall of the support wall 45 each time the temperature of the liquid to be filtered changes and the filter element 1 expands and contracts. I will wake you up. In addition, there is a problem that around the O-ring 43, elastic debris generated due to deterioration of the O-ring itself, dust or the like present in the liquid to be filtered easily accumulate.
[0012]
Accordingly, an object of the present invention is to provide an improved filter element that can prevent deformation and cracking of the filter element when it is fused and fixed to a housing without using an O-ring that involves problems relating to durability and reliability, and the It is to provide a filter cartridge using. In other words, the object of the present invention is to provide an improved and highly reliable filter element that does not deform or crack even when a high-temperature liquid is filtered, and that eliminates the use of a deteriorating elastic material as much as possible. Is to provide.
[0013]
[Means for Solving the Problems]
In one aspect of the present invention , the present invention provides a filter cartridge in which a filter element is accommodated in an airtight housing. The filter element supports a cylindrical filter material, an inner surface of the filter material, and a plurality of openings. Yes to and resin inner cylinder forming the inner filtrate passages, to support the outer surface of the filter material, for hot or cold liquid to be treated than the outside air between the number of and the housing have a opening resin of the outer cylinder for forming a passageway, a first resin disc-like cap which is hermetically fused to one end of the outer cylinder and the inner cylinder and the cylindrical filter material, and the cylindrical filter material and before composed of a second resin disc-like cap which is hermetically fused to the other end of Kigai side cylindrical, the cap portion at hotel is secured by the housing and the welding portion The inner cylinder has been made form rigidity rather higher than the outer cylinder to provide a filter cartridge, characterized in that said inner cylinder is not hermetically fused to the second circular plate-like cap portion.
[0014]
In a preferred embodiment, the non-hermetic portion is achieved by having a length that prevents the inner cylinder from reaching the second disc-shaped cap. In a preferred embodiment, the distance between the end of the inner cylinder on the pressure support side that is not hermetically sealed and the second disk-shaped cap is determined so that the heat conduction from the liquid during use of the filter element The amount of increase in the axial length of the cylinder on the pressure support side (or the amount of expansion) caused by the temperature rise of the inner cylinder on the pressure support side due to the above is set to an extent equal to
[0015]
In another aspect of the present invention, the present invention provides a filter cartridge in which a filter element is housed in an airtight housing. The filter element supports a cylindrical filter material, an inner surface of the filter material, and has a plurality of openings. have a and forms an internal filtrate passages resin inner cylinder and supporting the outer surface of the filter material, the hot or cold liquid to be treated than the outside air between the number of and the housing have a opening passages resin outer cylinder forming a for, before Symbol cylindrical filter material and said inner cylinder and said first resin disc-like cap portion is hermetically fused respectively to upper and lower ends of the outer cylindrical second consists of a resin disc-like cap portion, the two cap portions are fixed in the housing and the welding portion, said inner cylinder is the outer cylinder the pressure bearing side Remote rigidity has been made high rather form, the inner cylinder is formed from a first cylindrical member and the second cylindrical member, away side end from the cap portion of the first cylindrical member and the second circular cylinder member parts provides a filter cartridge that is configured to be movable relative.
[0016]
In a preferred embodiment, the relatively movable ends of the first and second cylindrical members are configured to be nested. In another embodiment, the relatively movable end is constructed in a tenoned manner. In a preferred embodiment, the relative movable distance between the first and second cylindrical members is caused by a temperature increase of the cylinder on the pressure support side due to heat conduction from the liquid during use of the filter element. It is about the same as the increase amount (or expansion amount) of the axial length of the cylinder on the pressure support side.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a cross-section of a filter cartridge containing a filter element 1 according to one aspect of the present invention in a housing 13 . In FIG. 1, members or components similar to those in FIG. 5 are denoted by the same numbers. The illustrated filter cartridge accommodates a filter element 1 according to one aspect of the present invention having a filtering action in an airtight housing 13 having a manifold (collecting portion) having various inlets and outlets. More specifically, the filter element 1 includes a cylindrical filter material 3, a resin-made inner cylinder 5 and outer cylinder 7 having a large number of openings, and resin caps 9 and 11. The filter element is a disposable type which is integrally connected to the housing with welds 19 as shown FIG.
[0018]
As shown in FIG. 1, the inner cylinder 5 of the filter element 1 of the present invention is configured to be slightly shorter than the outer cylinder 7, and between the upper end portion 62 of the inner cylinder 5 and the resin cap portion 9. A gap 70 is provided. The lower end portion 64 of the inner cylinder 5 and both end portions of the outer cylinder are fixed to the resin cap portions 9 and 11 in a sealed state by fusion or the like, similarly to the filter element of the prior art. When it is necessary to accurately position the inner cylinder 5 or when it is necessary to increase the resistance against the pressure of the inner cylinder, the annular guide portion 72 may be provided as an auxiliary member. It will be apparent to those skilled in the art that the gap 70 may be provided between the lower end portion 64 of the inner cylinder 5 and the resin cap portion 11. Also, unlike the prior art (FIG. 5), the filter element 1 is completely fixed to the housing 13 by welding or the like at both upper and lower ends, and as a whole, has higher rigidity than the prior art. Yes.
[0019]
Here, the actual operation of the filter element will be described. For simplicity of explanation, in the following explanation, it is assumed that the expansion coefficients of all members used in the filter cartridge are all the same. It will be apparent to those skilled in the art that the substantial content of the following description does not change when the expansion coefficients are different.
[0020]
When a liquid to be processed having a high temperature (for example, 100 to 180 ° C. ) flows from the inlet 21, the filter element 1 is immersed in the high-temperature liquid and tends to expand due to heat conduction from the liquid. At this time, the temperature of the housing 13 itself also rises due to the high-temperature liquid, but since the outside of the housing 13 is exposed to the surrounding environment (or the atmosphere), the temperature rise is smaller than that of the filter element. As a result, thermal stress is generated in the filter material 3 and the outer cylinder 7 due to a temperature difference with the housing 13, but the filter material 3 and the outer cylinder 7 are formed with a relatively flexible or elastic structure. Therefore, the generated thermal stress can be absorbed.
[0021]
On the other hand, the inner cylinder 5 is formed in a relatively rigid structure in order to hold the filter material 3 to which a relatively strong pressure is applied in the center direction at a predetermined position. However, as shown in FIG. 1, there is a gap 70 between the inner cylinder 5 and the resin cap 9, and the inner cylinder 5 is in the direction of the arrow 80 by a distance equal to the gap 70. Since it can expand, no thermal stress is generated.
[0022]
As will be apparent from the above description, the gap 70 is preferably a distance (more than the same amount as the increase (or expansion) of the inner cylinder 5 caused by heat conduction from the liquid to be filtered. Exactly, it is desirable that the distance is an interval obtained by subtracting the expansion amount of the housing 13 from the expansion amount of the inner cylinder 5. However, considering that the inner cylinder 5 and the housing 13 have a certain degree of elasticity, even if the gap 70 is actually smaller than the increase caused by thermal expansion, it is possible to prevent deformation and cracking of the filter element 1. It will be apparent to those skilled in the art that a sufficient effect can be achieved. Further, if there is no structural or strength problem, the gap 70 may be larger than the increase actually caused by thermal expansion.
[0023]
FIG. 2 illustrates a filter cartridge containing a filter element 1 according to another aspect of the present invention. Also in this embodiment , the filter element 1 is welded at both the upper and lower ends, and is completely fixed to the housing 13 by welding or the like, and as a whole, has higher rigidity than the prior art. The inner cylinder 5 of the filter element 1 includes an upper cylindrical member (first cylindrical member) 82 and a lower cylindrical member (second cylindrical member) 84. As shown in the drawing, the end portions 86 and 88 far from the fusion-sealed portions of the first and second cylindrical members 82 and 84 are configured to be nested, and are configured to be movable relative to each other in the axial direction. Has been. Here, for example, when the coupling portion of the first and second cylindrical members 82 and 84 is arranged at the center, the axial length of the first and second cylindrical members 82 and 84 is the inner cylinder of the embodiment of FIG. The amount of expansion is about half of that of the inner cylinder of FIG. However, as indicated by arrow 90 in FIG. 2, the first and second cylindrical members 82, 84 both expand toward the center, so the relative distance traveled by the ends 86, 88 is that of FIG. The amount of increase in the inner cylinder 5 is about the same. Accordingly, the relatively movable distance between the end portions 86 and 88 is also the same distance as the increase in the inner cylinder 5 caused by heat conduction from the liquid to be filtered (more precisely, the expansion amount of the inner cylinder 5). It is desirable that the distance is an interval obtained by subtracting the expansion amount of the housing 13 from the distance. However, as described above with the embodiment of FIG. 1, it should be understood that they work well even if the travel distance does not match the increase.
[0024]
FIG. 3 shows, as another embodiment of the present invention, a joint portion between the first cylindrical member 82 and the second cylindrical member 84, which has a dovetail shape. FIG. 4 is an exploded perspective view of another embodiment of the inner cylinder of the present invention. As shown, the embodiment of FIG. 4 utilizes a nested structure in which the end 88 of the second cylindrical member 84 enters the inside of the end of the first cylindrical member 82 and when they are joined together. In order to prevent the cylindrical members from rotating with respect to each other, a mortise-like structure (that is, a protrusion and a recess) is provided. As will be apparent to those skilled in the art, the connecting portion of the first and second cylindrical members 82, 84 has the structurally required strength and is relatively relative when the cylindrical members are thermally expanded. Any configuration is possible as long as it is movable.
[0025]
Although the invention has been described with the illustrated embodiments, it should be understood that various modifications can be made to the invention. For example, in the embodiments, the support side cylinder has been described as an inner cylinder, but for example in filter cartridges where the liquid inlet is in the center and the outlet is located on the outside, the outer cylinder is on the support side. It will be a cylinder. In addition, although the coupling portions 86 and 88 of the first and second cylindrical members are illustrated in a state of being disposed in the center with respect to the axial direction, it may not be disposed in the center, It should be understood that may be arranged in multiple pieces. Furthermore, although the embodiments of the present invention have been described for the filtration of hot liquids, the filter elements of the present invention can be made cooler than the ambient temperature by adjusting the gap 70 and the spacing of the couplings 86,88. It will be apparent to those skilled in the art that it can be applied to liquid filtration.
[0026]
【The invention's effect】
An improved filter element according to the present invention that does not cause deformation or cracking of the filter element even when high-temperature or low-temperature liquid is filtered without using an O-ring that is less durable or reliable than other components. Can be provided. In addition, since the inner cylinder of the filter element of the present invention can be configured to expand or contract by an interval corresponding to thermal expansion, the material is selected without considering the thermal expansion coefficient or the like when manufacturing the inner cylinder. Make it possible. In addition, unlike conventional filter elements, the filter element can be manufactured with little consideration of strength against thermal stress, and the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a filter cartridge containing a filter element according to one aspect of the present invention.
FIG. 2 is a cross-sectional view of a filter cartridge containing a filter element according to another aspect of the present invention.
FIG. 3 is an enlarged plan view of first and second cylindrical members for illustrating a coupling portion according to another embodiment of the present invention.
FIG. 4 is an exploded perspective view of another embodiment of an inner cylinder according to the present invention.
FIG. 5 is a cross-sectional view of a filter cartridge containing a conventional filter element.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Filter element 3 Filter material 5 Inner cylinder 7 Outer cylinder 9, 11 Resin cap part 13 Housing 15 Lid part 17 Housing part 19 Welding location 21 Inlet 23 of liquid to be processed Primary side channel | path 25, 27 Opening of cylindrical member 29 Secondary Side passage 33 Secondary side outlet 35 Primary side gas vent port 35 'Primary side drain port 39 Secondary side gas vent port 39' Secondary side drain port 41 Annular wall 43 O-ring 45 Cylindrical support wall 51 Support member 62 Upper end of inner cylinder Portion 64 Lower end portion 70 of inner cylinder 72 Gap 72 Guide portion 82 First cylindrical member 84 Second cylindrical member 86 End portion 88 of first cylindrical member End portion 92 of second cylindrical member Welded portion

Claims (6)

In the filter cartridge formed by accommodating a filter element in the air-tight housing, said filter element includes a cylindrical filter material, to support the inner surface of the filter material, have a large number of openings and made of a resin for forming the inner filtrate passage inner cylinder, to support the outer surface of the filter material, the resin of the outer cylinder forming a path for hot or cold liquid to be treated than the outside air between the closed and and the housing a large number of openings, the The first and second resin disk-like cap parts, which are hermetically fused to the upper end and lower end parts of the cylindrical filter material, the inner cylinder and the outer cylinder, respectively, and both the cap parts. is fixed in the housing and the welding portion are rigid formed higher than the inner cylinder the outer cylinder the pressure bearing side, said inner cylindrical It is formed from the first cylindrical member and the second cylindrical member, a filter cartridge end remote from the cap portion of the first cylindrical member and the second cylindrical member is configured to be relatively moved. 2. The filter cartridge according to claim 1, wherein end portions of the first cylindrical member and the second cylindrical member that are movable relative to each other are configured to be nested or dovetailed. The distance by which the first cylindrical member and the second cylindrical member can move relative to each other is in accordance with an increase in the length of the cylinder on the pressure support side caused by a temperature rise of the cylinder on the pressure support side during use. Item 1. The filter cartridge according to item 1. In the filter cartridge formed by accommodating a filter element in the air-tight housing, said filter element includes a cylindrical filter material, made of resin and form a internal filtrate passages have a support and a number of openings to the inner surface of the filter material inner cylinder, to support the outer surface of the filter material, the resin of the outer cylinder forming a path for hot or cold liquid to be treated than the outside air between the closed and and the housing a large number of openings, the the first resin disc-like cap which is hermetically fused to the cylindrical filter material and the inner cylindrical end portion of the outer cylinder, and hermetically welded to the other end of the cylindrical filter material and before Kisotogawa cylindrical composed of a second resin disc-like cap portion which is, the cap portion is fixed in the housing and the welding portion, the rigidity inner cylinder from the outer cylinder Are formed high, filter cartridge, characterized in that said inner cylinder is not hermetically fused to the second disk-like cap portion. 5. The filter cartridge according to claim 4, wherein the inner cylinder has a length that does not reach the second disk-shaped cap portion and is not hermetically fused to the second disk-shaped cap portion. Between the end portion of the inner cylinder and the second disc-shaped cap portion, there is a length interval according to the increase in the axial length of the inner cylinder caused by the temperature rise of the inner cylinder in use. The filter cartridge of claim 4, wherein the filter cartridge is open.

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