JPH0536492Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a super-element of a laminated filter.

[Conventional technology]

Multilayer filters are used for purifying chemical solutions in semiconductor manufacturing processes. For example, JP-A-60-
22904, an example of which is shown in the second
As shown in the figure. The laminated filter 10 shown in FIG.
7 are stacked and the center bolt 18 connects the inlet hole 19.
It is fixed to the outlet hole 19b of the casing 19 provided with the outlet hole 19b, and is made entirely of chemical-resistant synthetic resin.

As shown in FIG. 3, the spacer 13 of the over-element 17 has a boss portion 11 having a central through hole 11a.
A horizontal plate 12 is provided on the side of the plate 11, and a lateral hole 12a is provided inside the plate 12, which is connected to the central through hole 11a. The plate 14 is made of two mesh bodies 15 sandwiching a thin porous membrane 16 between them. The periphery of the central hole 14a is made of the horizontal plate 12.
The material 14 is heat welded to the upper or lower surface of the material 2 to form a welded portion 15a. The outer peripheral edge of the material 14 is airtightly welded to the material welded to the upper surface and the material welded to the lower surface to form a bag shape.
At a, the knitting yarn of the net body 15 has melted and become a film (film-formed).

The over-element 17 is stacked and the material 14 is bent and housed in the casing 19.

[Problem that the invention attempts to solve]

The boundary between the filmed part of the net body 15 of the material 14 and the part where the original knitting yarn remains is easy to bend, so the material 14 is bent and the casing 1
9 or when the liquid pressure of the stock solution is
4, this boundary part receives concentrated stress. Furthermore, when the material 14 is bent, concentrated stress is generated in the portion where it hits the outer peripheral edge of the horizontal piece 12 and is bent; however, due to the shape of the horizontal piece 12, this portion
Since it is close to the aforementioned boundary portion, the concentrated stress due to both of the aforementioned reasons acts on almost the same location.
Therefore, the portion where the boundary of the film portion of the material 14 overlaps the outer peripheral edge corner of the horizontal piece 12 becomes the weakest point of the material and causes breakage.

Therefore, a wider area of the net 15 than the part to be thermally welded is made into a film in advance, and the boundary between the film part and the knitting yarn part of the net 15 is shifted outward from the corner of the horizontal piece 12, and the above-mentioned material is made into a film. It is possible to avoid duplication of reasons that cause weaknesses in 14. However, in this way, the filmed part can be
If the diameter is larger than 2, when the pressure of the stock solution is applied from the outside to the upper and lower two materials 14, the filmed part will be compressed and the liquid passage between the two materials will be blocked or pinched. . This is because the filmed portion loses some of the elasticity of the material maintained by the net and becomes completely flexible. This clogging phenomenon is remarkable in the case of high viscosity liquids such as sulfuric acid.

This invention is intended to solve these problems.

[Means for solving problems]

A synthetic resin spacer consisting of a boss and a horizontal piece annularly provided on the side of the boss has a synthetic resin material with a mesh layered on both or one side of the porous membrane on the upper and lower surfaces of the horizontal piece. At the same time as welding the periphery of the center hole, a filtered part was formed on the welded part of the material and its outer periphery in an area wider than the outer diameter of the horizontal piece, and a porous interlayer was inserted between the two materials. This is a multilayer filter element. It should be noted that since the intermediate material prevents the film portion of the material from coming into close contact with each other, it does not need to extend to near the outer periphery of the material.

[Effect]

A plurality of over-elements of this invention are stacked, one end of the communicating central through-hole is closed, each member is bent and housed in the casing, and the other end of the central through-hole is connected to the outlet hole of the casing. Form a mold film.

The welded part of the cross-element with the horizontal piece of material and its outer peripheral part are both made of film, and the boundary between the film part of the net and the knitted thread-like part is further outward than the outer peripheral edge of the horizontal piece. be. Therefore, the boundary of the film-formed part of the material and the part where the material touches the corner of the horizontal piece are misaligned, and the concentrated stress when the material is warped overlaps and is dispersed instead of being applied to one place. be done.

Further, even if the filmed portion extends outward from the outer peripheral edge of the horizontal piece, the inserted intermediate material prevents the passage between the two materials from being blocked.

〔Example〕

FIG. 1 shows an embodiment of this invention. The over-element 1 of the present invention includes a spacer 13, a material 4, and an intermediate material 7.
It is made entirely of chemical-resistant synthetic wood material. The spacer 13 has a boss portion 11 having a central through hole 11a.
and a central through hole 1 provided in an annular shape on its side.
Horizontal piece 12 equipped with a horizontal hole 12a communicating with 1a
It becomes.

The material 4 is made by stacking two nets 5 with a thin porous membrane 6 sandwiched between them, with a central hole 4a.
The peripheral edges of the horizontal piece 12 are thermally welded to the upper and lower surfaces of the horizontal piece 12 to form a film shape. The net body 5 is formed with a film portion 5a that extends outward from the welded portion and has a larger diameter than the outer peripheral edge of the horizontal piece 12. Before forming the material 4 by overlapping the net 5 of the film portion 5a with the membrane 6, an annular heating plate is pressed against only the net 5 to melt the knitting yarns of the net 5. This net body 5 is overlapped with a membrane 6 made of a porous tetrafluoroethylene membrane to form a material 4 with a central hole 4a.
The peripheral edges of the spacer 13 are thermally welded to the upper and lower surfaces of the horizontal piece 12 of the spacer 13. A ring-shaped nonwoven fabric made of synthetic resin fibers is inserted as a porous interlayer 7 between two members 4 welded to the upper and lower surfaces of the horizontal piece 12. The intermediate material may also be a flexible net-like board. The material 4 is welded to the upper surface and lower surface of the horizontal piece, and the outer peripheral edge is welded airtight to form a bag. Material 4
may be circular or polygonal such as a square. The over-element 1 thus formed is stacked in a similar manner to the conventional one, and the center bolt 18 is inserted therethrough and attached to the outlet hole 19b of the casing 19. At this time, each member 4 is bent and the casing 1
It is accommodated within 9. The outer peripheral edge of the horizontal piece of the material 4 is particularly strongly bent and is also strongly subjected to the pressure of the inflowing raw solution, but the ends of the thread-like portions of the net 5 are not in this position, so the concentrated stress due to both of the above reasons does not overlap. do not have. Furthermore, since the interlayer is inserted, the internal passage between the members will not be blocked.

In addition, the material 4 may be arranged so that the mesh members 5 are stacked only on one side of the membrane 6 so that the membranes are not directly adjacent to each other when stacked. Furthermore, when stacking over-elements, the end faces of the boss portions may be fixed and the center bolt may be omitted.

〔effect〕

In this idea, the welded part of the over-element with the horizontal piece of material and its outer periphery are made into a film, and the boundary with the thread-like part is made not to coincide with the part that corresponds to the outer periphery of the horizontal piece, so that the material does not warp. The concentrated stress is dispersed when the stress is applied, resulting in an over-element that is less prone to breakage. Furthermore, since the film portion does not block the passage due to the interlayer material, a laminated filter with stable performance and long life can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the over-element of this invention. FIG. 2 is a diagram of a laminated filter, and FIG. 3 is a diagram of a conventional filter element. 4... Material, 5... Net body, 5a... Filmed portion, 6... Permeable membrane, 7... Intermediate material, 10... Laminated filter, 11... Boss portion, 12... Horizontal piece,
13...Spacer.

Claims (1)

[Scope of utility model registration request] On the upper and lower surfaces of the horizontal piece of the synthetic resin spacer, which is composed of a boss portion having a central through hole, and a horizontal piece provided annularly on the side surface of the boss portion and having a horizontal through hole inside that communicates with the central through hole, The periphery of the central hole of a material made of a synthetic resin material with a mesh layered on both sides or one side of a porous membrane is welded, and the outer periphery of the two materials is hermetically welded. A laminated filter characterized in that, in the element, a film portion having a diameter larger than the outer diameter of the horizontal piece is formed around the center hole of the mesh body, and a porous intermediate material is inserted between the two materials. excess element.