JPH0337703Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a laminated type precision filter mainly used as a filter for treating various chemical solutions, pure water, or gas bodies.

(Prior art) Filters for treating chemical liquids and gases used in the production of various pharmaceuticals and electronic components, as well as pure water used in the food industry, have chemical resistance and heat resistance, and have filtration accuracy on the submicron order. Recently, filters such as those shown in FIG. 4 (a) and (b) have been used to meet this demand.

That is, the whole desk is made of a synthetic resin with high chemical and heat resistance such as tetrafluoroethylene, polypropylene, or nylon, and as shown in Figure 1, a circular desk 1 has a slightly higher annular shape on the upper and lower surfaces. A plurality of rows of chevron-shaped protrusions 2a meandering from the boss portion 1a toward the outer peripheral portion 1b are separated by radial grooves 2b, and the meandering protrusions 2a on the upper surface and the protrusions 2a on the lower surface are shifted in position in the circumferential direction. and each radial groove 2b
communicates with the inside of the central boss portion 1a, and porous annular thin film filter media 3 are disposed above and below this circular desk 1, and its outer periphery is connected to the outer periphery 1 of the circular desk 1.
b is welded to form a desk element, a required number of desk elements are stacked, an annular upper end plate 4a is provided at the upper end, a middle plate-shaped lower end plate 4b is provided at the lower end, and the uppermost desk element is laminated. The inner peripheral edge of the thin film filter medium 3 on the upper surface of the desk element is welded to the lower surface of the center of the upper end plate 4a, while the inner peripheral edge of the thin film filter medium 3 on the lower surface of the lowermost desk element is welded to the upper surface of the center part of the lower end plate 4b. However, in other parts, the inner peripheral edge of the thin film filter medium 3 on the lower surface of the upper element and the inner peripheral edge of the thin film filter medium 3 on the upper surface of the lower element are welded to each other to connect the whole in a bellows shape, and then the upper end The upper surface of the central part of the plate 4a is welded to the lower end of the central outlet pipe 6a of the cover 6, and in this state the laminated element is housed in the pot-shaped container 5, and the lower end plate 4b
is received by the radiation rib 7 on the bottom wall, and when in use, the inlet pipe 5a at the lower end of the container
The processing fluid is introduced into the container 5, purified by passing through the thin film filter medium 3 of the desk element from the outer periphery, and sent to a required location from the outlet pipe 6a.

(Problem to be solved by the invention) By the way, in the bellows-type laminated filter as described above, positive pressure (from the outside to the inside) is applied to the thin film filter medium of each desk element when it is used in a fluid circuit and when it is stopped. If the desk elements are subject to alternating pressure (inward pressure) or counter pressure (pressure from the inside to the outside), and the gap between the desk elements is large, the thin membrane filter material may swell and the welded part may peel off, so the number of layers is large. However, on the other hand, if there are too many layers, the variations in the thickness of each desk element will be compounded and it will become impossible to accommodate them in the container, and conversely, if you try to avoid this, the gaps between the elements will become large. This will cause the problems mentioned above.

Therefore, this invention provides a precision filter that can maintain appropriate gaps between desk elements even if there are variations in the thickness of each desk element.

(Means for Solving the Problems) Based on the above object, this invention provides a circular desk which has an annular boss in the center and has fluid flow channels, such as radial grooves, on the upper and lower surfaces communicating with the inside of the boss. Thin film filter media are arranged above and below the desk, and the outer peripheral edges of the filter media are welded to the outer peripheral part of the desk, and the required number of desk elements are stacked, and an annular upper end plate is placed on the upper end of the desk element, and a disc-shaped lower end plate is placed on the lower end of the desk element. End plates are arranged, and the inner periphery of the uppermost thin film filter material is welded to the upper end plate, the inner periphery of the lowermost thin film filter material is welded to the lower end plate, and the inner periphery of the upper and lower thin film filter media is welded to the lower end plate at intermediate stages. The filter is welded together and housed in a container, and is characterized in that a spacer of a required thickness is provided between the rib on the bottom wall of the container and the lower end plate of the laminated element.

(Example) Figure 1 shows an example of this invention, which is entirely made of synthetic resin with chemical and heat resistance such as tetrafluoroethylene and polypropylene.
On the upper and lower surfaces of the circular desk 1, a plurality of rows of chevron-shaped protrusions 2a are formed, which are separated by radial grooves 2b and meander from an annular boss portion 1a with a center height slightly higher than the others toward an outer peripheral portion 1b. Meandering protrusion 2a
and a meandering protrusion on the lower surface are shifted in position in the circumferential direction, each radial groove 2b communicates with the inside of the boss portion 1a, and a porous annular thin film filter material 3 is provided above and below the circular desk 1. is arranged, and its outer periphery is welded to the outer periphery of the circular desk 1 to form a single desk element, and the required number of desk elements are laminated, with an annular upper end plate 4a at the upper end and an annular upper end plate 4a at the lower end. A disk-shaped lower end plate 4b is disposed, and the inner peripheral edge of the thin film filter material 3 on the upper surface of the uppermost desk element is welded to the central lower surface of the upper end plate 4a, while the thin film filter material on the lower surface of the lowermost desk element 3 is welded to the upper surface of the central part of the lower end plate 4b, and at the middle stage, the inner peripheral edge of the thin film filter medium 3 on the lower surface of the upper desk and the inner peripheral edge of the thin film filter medium 3 on the upper surface of the lower desk are welded to each other, so that the whole becomes a bellows. The upper surface of the central part of the upper end plate 4a is welded to the lower end of the central outlet pipe 6a of the cover 6 before this laminated element is housed in the pot-shaped container 5. The configuration of the points is the same as the conventional one.
By the way, in this invention, a spacer 10 consisting of a flange portion 10a having a required wall thickness and a support tube portion 10b is provided at the bottom of the container 5, and the support tube portion 10b is provided on the bottom wall of the container 5 as shown in FIG. The bellows-shaped laminated element is fitted inside a plurality of radial ribs 7 and is disposed such that the flange portion 10a is placed on each rib, and the bellows-shaped laminated element is brought into contact with the lower end plate 4b of the flange portion 10a. is housed in a container 5, a cover 6 is applied to the open end of the container 5, and the periphery of the cover 6 is welded to the container 5.

In this case, if the laminated elements cannot be accommodated in the container 5 due to the accumulation of variations in the wall thickness of each desk element, one or two of the desk elements may be removed and a flange wall that can maintain an appropriate gap between each element may be used. A thick spacer 10 is selected and provided on the rib 7, and also when the height of the entire stacked element is low and if it were housed in the container 5 as it is, the gap between each desk element would be large. A spacer 10 with a flange thickness that does not widen the gap is selected and placed on the rib 7.

Therefore, during use, the processing fluid enters the container 5 from the inlet pipe 5a and pressure acts on each thin membrane filter medium 3 from the outside to the inside, or when the apparatus is stopped, the thin membrane filter medium 3 of each desk element is exposed to the outlet pipe 6.
Even if fluid pressure acts from the inside through a,
Since the gaps between each desk element are maintained appropriately, the thin membrane filter medium 3 will not swell abnormally.
No excessive tensile force is applied to the welded part. Note that the spacer 10 for adjusting the height is not formed as a separate member, but is formed integrally as an annular protrusion of the required thickness (height) on the lower surface of the lower end plate 4b of the laminated element as shown in FIG. You can.

(Effects of the invention) As described above, in this invention, thin film filter media are arranged on the top and bottom of a circular desk with an annular boss in the center and fluid flow channels on the top and bottom surfaces, and the outer periphery of the filter is placed on the outer periphery of the desk. The required number of welded elements are laminated, and a spacer of the required thickness is placed between the lower end plate and the rib on the bottom wall of the container to create a filter that uses a bellows-type laminated element that welds the inner edges of the upper and lower thin film filter media to each other. Because the desk elements are interposed between each other, the gaps between each desk element can be maintained appropriately, and the thin film filter media between the desks can be supported in a close state, preventing positive pressure or reverse pressure from being applied to the filter media when in use or when stopped. Even if it was Katata,
The thin membrane filter medium will not swell abnormally and be damaged, and the welded portion will not peel off.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of this invention. FIG. 2 is a perspective view of the spacer portion. FIG. 3 is a sectional view of the bottom of a modified example of the container. Figure 4A is a cross-sectional view of the conventional product. Figure B is a perspective view of a portion of the circular desk. In the figure, 1...Circular desk, 1a...Boss part, 1
b...Outer peripheral part, 2a...Chevron protrusion, 2b...Radial groove, 3...Thin membrane filter medium, 4a...Upper end plate, 4b
... lower end plate, 5 ... container, 6 ... cover.

Claims (1)

[Scope of utility model registration request] A circular desk 1 having an annular boss portion 1a in the center and having fluid flow paths communicating with the inside of the boss portion on the upper and lower surfaces.
Thin film filter media 3 are disposed above and below the desk 1, and the outer peripheral edge thereof is welded to the outer peripheral part of the desk 1. A required number of desk elements are stacked, and an annular upper end plate 4a is attached to the upper end of the desk element.
A disk-shaped lower end plate 4b is arranged at the lower end, and the inner peripheral edge of the thin film filter medium 3 in the uppermost stage is connected to the upper end plate 4a, and the inner peripheral edge of the thin film filter medium 3 in the lowermost stage is connected to the lower end plate 4b. In the case where the inner peripheral edges of the upper and lower thin film filter media 3 are welded to each other at the step part in the middle and housed in the container 5, the rib 7 on the bottom wall of the container 5 and the lower end plate 4b of the laminated element are A laminated precision filter comprising a spacer 10 of a required thickness between the two.