JPS646888Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a spacer for a laminated precision filter element.

For example, as shown in the cross section of FIG. 1, a laminated precision filter is constructed by welding a pair of materials 1 to a spacer 2 to form a filter unit 3, which is then laminated with a center bolt 4 to form a cover having a liquid outlet 5a. 5, and the cover 5 is fixed to the open end of a case 6 having a stock solution inlet 6a. Since the filter is mainly used for precise handling of chemical solutions, the above-mentioned members forming the filter are made of synthetic resin with excellent chemical resistance, and each joint portion is bonded and sealed by heat welding. A filter element 3 of such a filter is illustrated in FIG.
The spacer 2 includes a cylindrical boss portion 22 with a central through hole 21 and an annular collar portion 23 that projects laterally from the side surface of the boss portion 22, which are integrally formed of synthetic resin. The side opening 24 of 23 and the central through hole 21 communicate with each other through a flow path 25 bored inside the collar. The member 1 is made up of a porous thin film 11 made of fluorine resin and a net cloth 12 made of synthetic resin overlaid on both sides thereof, and has an opening 13 in the center into which the boss portion 22 is inserted. Two pieces of this material 1 form a pair, and the periphery 14 of the opening 13 is welded to the annular upper and lower surfaces 26 and 27 of the collar 23, respectively, and the outer periphery 15 of the pair of materials is welded and sealed into a bag shape. Ru. The conventional filter element as described above accommodates as many layers as possible in the filter case,
In order to increase the effective area of each filter element, the spacer is made as small as possible, and the length of the annular protrusion and the thickness of the side surface of the flange are made as small as possible. Moreover, the material is made to have appropriate elasticity, and is layered with net cloth to prevent the membranes from coming into direct contact with each other and blocking the flow path, making the material quite thick overall. When welding to the upper and lower surfaces of the collar, considerable melting burrs (see FIG. 2, 28) are generated, which may flow out to the sides of the collar and block the side openings of the flow passages. In addition, as mentioned above, this type of filter is made of a chemical-resistant material such as fluorine resin, and has a narrow tolerance range for welding conditions such as heating temperature. There are problems such as overheating the entire part, or failure to weld the flat surfaces evenly, resulting in seal leakage.

An example of such a conventional spacer 2 is shown in FIG.

This invention is intended to eliminate the above-mentioned problems by improving the shapes of the upper and lower surfaces of the spacer brim and providing annular protrusions on the annular plane.

To describe an embodiment, FIGS. 4 and 5 show a spacer 30 of this invention. The spacer 30 is made of a synthetic resin material and has a cylindrical boss portion 32 having a central through hole 31 and a collar portion 33 extending from the side surface thereof. The opening 34 on the side surface of the flange 33 and the central through hole 31 communicate with each other through a flow passage 35 bored in the flange 33 . Above the brim,
One or more annular protrusions 38 are provided on the lower annular planes 36 and 37, respectively.

The material 1 is attached to the spacer 30 of this invention as described above.
When welding to the upper annular plane 36, the annular plane 3
When 6 is heated from the outside with a heat source, the protrusions 3 first
8 is heated from the top and then extends to the annular plane 36, so when the material 1 is crimped, the convex strip 38 is first welded into an annular shape, and the melted burr 39 flows out to the annular plane 36, joining the material 1 and the annular plane 36, It will not flow out to the sides of the brim. The same applies when welding the material 1 to the lower plane 37. Since the spacer 30 of this invention works as described above, melted burrs will not block the side opening of the flow path and impede its function, and since welding is first performed in an annular shape on the convex portion, sealing is ensured. There is a certain effect.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a laminated precision filter, FIG. 2 is a sectional view showing its filter element, FIG. 3 is a perspective view showing a conventional spacer, and FIG. 4 is a perspective view showing a spacer of this invention. FIG. 5 is a sectional view showing the state of welding of the spacer and material of this invention. 1... Material, 30... Spacer, 36, 37...
... Upper and lower annular planes of the brim, 38... Convex stripes.

Claims (1)

[Scope of utility model registration request] It consists of a cylindrical boss having a central through hole and a protruding flange integrally formed on the side surface of the boss, and inside the flange is a flow passage that communicates the opening on the side of the flange with the central through hole. A spacer for a laminated precision filter having a perforated spacer, characterized in that annular protrusions are provided on the upper and lower annular surfaces of the brim portion,
Spacer for laminated precision filter element.