JPH0713785Y2 - Filter element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a filter element using a polymer filter material such as a porous membrane such as a fluororesin.

[Conventional technology]

In recent years, it has been required to supply ultra-clean gas, water, chemicals, etc. in the food field, semiconductor field, etc., and in order to obtain them, all-resin flat-membrane filter media made of fluororesin, polypropylene, or other resin with chemical resistance. A multi-stage type filter element or a pleated filter element using is used. The multistage filter element has a problem in treating a liquid having a high effective viscosity with a small effective filtration area, and a pleat-shaped filter element having a large effective filtration area and capable of treating a large amount of a chemical solution is often used.

As shown in FIG. 5, this pleated filter element has a reinforcing material such as a mesh cloth superposed on both front and back surfaces of a thin film having chemical resistance, and both edges are welded and integrated as a filter material, This is pleated into chrysanthemums to form a filter body 20. Cylindrical perforated cylinders 21 and 22 made of synthetic resin are fitted inside and outside the filter body 20, and end plates 23 and 24 made of synthetic resin are melted and fixed to the upper and lower ends thereof. The filter element 25 is arranged in a casing 28 made of synthetic resin and having inlet / outlet pipes 26, 27.

[Problems to be solved by the device]

By the way, since this filter element is for treating chemicals, adhesives such as vinyl chloride resin and epoxy resin that are usually used cannot be used because they dissolve or shrink, so they are similar to filter media. A melt of a chemically resistant synthetic resin must be used as an adhesive. However, the molten resin has a high viscosity and solidifies relatively quickly, and when the filter body with the inner and outer porous cylinders inserted is welded to the end plate, the molten resin is cooled by the contact of the porous cylinders and the viscosity of the molten resin increases. For example, there is a problem in that the edge of the filter medium is curled up or the molten resin does not sufficiently enter the end portion of the filter medium, resulting in defective bonding. Further, the resin solidifies before the end portion of the filter medium reaches the specified dimension into the molten resin, and the height dimension of the filter element becomes uneven.

[Means for Solving the Problems]

The present invention provides a filter element that solves such problems. A filter element formed by stacking a reinforcing material composed of a mesh of synthetic resin on at least one side of a porous polymer membrane composed of synthetic resin is a filter element. Formed into a ring-shaped filter body by providing step portions formed inside and / or outside of the filter body by cutting at both end portions in a substantially perpendicular direction, and from the step portion A synthetic resin perforated cylinder in which thin and annular thin parts are respectively formed is inserted, and further synthetic resin end plates are arranged at both ends thereof, and the thin part of the perforated cylinder is fused to the end plates. In addition to being fixed, the step portion is located on the surface of the melt-fixed layer.

[Action]

Since the thin portion of the perforated cylinder inserted into the molten resin layer on the end plate has a small volume (heat capacity) in the molten resin layer, the amount of heat taken by the molten resin may at least hinder the insertion of the filter medium and the perforated cylinder. Absent. Then, as the step portion comes into contact with the surface of the molten resin, the penetration resistance increases, and the absorption of heat of the molten resin increases the viscosity to prevent excessive penetration of the perforated cylinder.

〔Example〕

The medicated filter element 1 shown in FIG. 1 comprises a filter body 2, a porous inner cylinder 3, a porous outer cylinder 4, and end plates 5 and 5 '.
The filter material constituting the filter body 2 is made of a synthetic resin having chemical resistance and weather resistance such as fluororesin or polypropylene and has a thickness of
It is a porous polymer film of about 50 to 200 μ, and a reinforcing net cloth made of polypropylene with a thickness of about 0.3 mm is overlapped on both front and back sides, and the left and right edges are welded by means of high frequency, ultrasonic wave, etc. The welded part is formed and the three parts are integrated. The right and left edges of the filter material and the mesh cloth may be left as they are without being welded. The filter medium is pleated by a folding machine (not shown) and formed into a chrysanthemum-shaped ring to form the filter body 2. The porous inner cylinder 3 has a cylindrical shape and is made of fluororesin or polypropylene and has a thickness of about 3 to 5 mm. The upper and lower end portions of the porous inner cylinder 3 are cut at substantially right and left sides to form step portions 7, 7.
The step portions 7 and 7 have a thickness of about 0.5 to 1 mm over the height of 2 to 3 mm, respectively, and form the thin portions 6 and 6. The porous outer cylinder 4 is also made of the same material as the porous inner cylinder 3 and has a cylindrical shape, and has thin portions 8 and step portions 9, 9 having the same height as that of the porous inner cylinder 3 at the both edges.
Then, such a porous inner cylinder 3 and a porous outer cylinder 4 are fitted and inserted into the inside and outside of the annularly formed filter body.

The end plates 5 and 5'are made of a synthetic resin such as fluororesin or polypropylene and have a disk shape with a thickness of about 5 mm. One side thereof is heated to about 200 to 350 ° C by a heating means such as hot air, A resin molten layer 10 is provided which is melted to a depth of about 3 mm. In this case, an end plate shape holding jig (not shown) is arranged outside the end plates 5 and 5 '.

When the end portion of the filter body 2 in which the porous inner and outer cylinders 3 and 4 are fitted, that is, the melted portion is inserted into the resin molten layer 10, the thin portions 6 and 8 of the porous inner and outer cylinders 3 and 4 have a small heat capacity and Melting layer 10
The amount of heat absorbed by the molten resin is small, and therefore the molten resin enters the molten resin layer 10 before the viscosity of the molten resin becomes high. And the step portions 7 and 9
When the resin melt layer 10 reaches the resin melt layer 10, the contact plane area suddenly increases to increase the penetration resistance, and more heat of the resin melt layer 10 is taken away to increase the viscosity of the resin and prevent further penetration. It should be noted that the edge welded portion of the filter body 2 and the porous inner and outer cylinders 3 and 4 are formed into a resin molten layer.
When it is inserted into 10, the molten resin rises, but it wraps around inside the filter body 2 and increases the bonding area.

As another embodiment, as shown in FIGS. 2 and 3, a step portion 13 is provided on the inner or outer peripheral edge of the end of the porous inner cylinder, and a thin portion 12 extending from the step portion 13 is formed on the outer or inner peripheral edge. And a porous outer cylinder in which a step portion 16 is formed on the inner peripheral edge of the end of the porous outer cylinder 14 and a thin portion 15 extending from the step portion 16 is formed.
14 and 14 are inserted into the end plate 5.
Further, FIG. 4 shows a case where only the multi-perforated inner cylinder 17 is provided, and the thin portion 18 is inserted into the end plate 5. The operation of these is the same as that of the first embodiment.

[Effect of device]

As described above, according to the present invention, the perforated cylinder having the step portion and the thin wall portion is inserted into and / or outside the annular filter body, and the thin wall portion of the perforated cylinder is inside the melt-fixed layer of the end plate. In the above, the structure is such that the step portion is located on the surface of the melt-fixed layer while being melt-fixed, and the volume occupied by the part fixed in the molten resin layer of the perforated cylinder, that is, the heat capacity, is reduced. The amount of deprivation is small, the invasion resistance does not occur with the increase in viscosity, and the joining is performed under the condition that the viscosity of the molten resin is low. Furthermore, since a stepped portion cut at a right angle is formed at the end of the perforated cylinder, when this portion reaches the surface of the molten resin, the penetration resistance increases, and the increase in viscosity due to heat absorption of the molten resin increases the filtration penetration. To prevent. Therefore, it is possible to obtain a filter element which is well bonded to the filter body and the perforated cylinder and the end plate and is arranged at a predetermined position, and which is excellent in sealing property and has high dimensional accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a filter element of the present invention, FIGS. 2 to 4 are sectional views of other embodiments of the filter element of the present invention, and FIG. 5 is a conventional filter. FIG. 2 ... Filter body, 3, 11, 17 ... Porous inner cylinder, 4, 14 ... Porous outer cylinder 5, 5 '... End plate, 6, 8, 12, 15, 18 ... Thin-walled part 7, 9 , 13, 16 …… Step difference, 10 …… Resin melt layer

Claims (1)

[Scope of utility model registration request] 1. A filter medium formed by stacking a reinforcing material made of a mesh made of synthetic resin on at least one surface of a porous polymer membrane made of synthetic resin to form a chrysanthemum-shaped filter medium to form an annular filter body. A stepped portion formed inside and / or outside the filter body by being cut at substantially right angles at both end portions, and a thin annular thin portion is formed from the stepped portion. A resin perforated cylinder is fitted and further, synthetic resin end plates are arranged at both ends thereof,
A filter element in which a thin portion of the perforated cylinder is melted and fixed to the end plate and a step portion is located on the surface of the melted and fixed layer.