JPH0510899Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Field of Industrial Application] The present invention relates to a small filter suitable for use in a narrow space and under conditions that require high efficiency, such as a circulation filter in a small magnetic disk device. It is. [Prior Art] Conventionally, circulation filters for small magnetic disk devices that use material bent into pleats are housed in a small square casing and then glued around the material with a sealant. A crimp-seal type is often used, in which both ends of the sealed or folded material are held and sealed from above and below by comb-like protrusions provided on the casing and retainer. [Problem that the invention aims to solve] After storing the folded material in a square casing, the periphery of the material is adhesively sealed with a sealant. If the adhesive is perfect, high-efficiency material is used. Although it is advantageous in that it can achieve an overefficiency of 99.97% or more, which is the basic performance of HEPA filters, on the other hand,
Since ultra-small filters are required for those used in small magnetic disk devices, the limited excess area is reduced by impregnation with adhesive, and the workability during manufacturing is poor, resulting in high costs. There are other problems. In addition, both ends of the pleats of the material bent into pleats,
The crimp-seal type, which is clamped from above and below by interlocking comb-like protrusions, does not require adhesion with sealant, making assembly easy, and maintains the pleat spacing, making it easy to use as a separator. Although there are many advantages such as no need for sealing and lower manufacturing costs, the shape of the seal part bends along the comb tooth shape, which tends to cause minute gaps, making it impossible to obtain a perfect seal. Even if high efficiency materials are used, overefficiency of 99.97% cannot be achieved, and therefore
There were problems when using it as a HEPA filter. [Means and actions for solving the problems] The purpose of this invention is to take advantage of the many advantages of crimp-seal type filters and improve overefficiency in order to obtain satisfactory performance as a HEPA filter. Then, either one of the upper and lower comb-like protrusions that sandwich the folded material,
By providing a continuous line of protrusion along the comb-tooth shape approximately in the center of the thickness of the protrusion that forms the sealing surface, one side that holds the material forms a line contact.
By being able to adapt to minute changes in contact pressure,
This means that there is no gap and a nearly perfect seal is obtained. An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of the filter 10 showing a folded material 20 sandwiched between the upper casing 11 and the lower casing 24, and FIG. 2 is an exploded perspective view of the arrangement of parts. , FIG. 3 shows a 3-3 cross section in FIG. 2. Downward comb-like protrusions 14 and 15 are provided adjacent to the inner surfaces of both side walls 12 and 13 of the upper casing 11, and protrude further downward from the mating surface with the lower casing 24. In addition, there is a continuous protruding line 1 approximately in the center of the thickness along the comb tooth shape.
6 and 17 are provided respectively. The front wall 18 and the rear wall 19 have shapes suitable for sandwiching the folded ends 22 and 23 of the material 20, and the lower casing 2
It becomes the outer frame when fitting with 4. Upper comb-toothed protrusions 27 and 28 are disposed adjacent to both side walls 25 and 26 of the lower casing 24 so as to interlock with the comb-toothed protrusions 14 and 15, and the upper casing 11 The outer surfaces of the mutually protruding portions are the respective side walls 12, 13, and 2.
It is a contact fit with the inner surfaces of 5 and 26. Also, the front wall 2
9 and the rear wall 30 have comb tooth-like protrusions 27, 28.
Connected to both outer end rows of the material 20 and folded both ends 2 of the material 20
2 and 23, and serves as an inner frame when fitting with the front wall 18 and rear wall 19 of the upper casing 11, and is set so as to sandwich the material 20 and form an interference fit. Comb tooth-shaped projections 27, 2 of the lower casing 24
After the folds 21 of the material 20 are aligned and placed on the upper casing 8, the upper casing 11 is pressed and fitted. At this time, the protruding lines 16 and 17 provided on the comb-tooth-like protrusions 14 and 15 are added to the contact surface where the comb-teeth shapes interlock with each other, so that both ends of the pleats 21 of the material 20 are By pressing firmly, a complete seal can be achieved in no time. [Effect of the invention] As an example showing that the overefficiency of the invention is significantly improved, we compared a conventional type using high-efficiency materials (the shape is the same as the invented type, but without protruding lines) and the invented type. As a result of conducting 5 comparison tests under the same conditions,

[Table] As you can see from the table above, all five filters of this invention have overefficiency, which is the basic performance of HEPA filters.
99.97% or more, and it also has many of the advantages of the crimp seal type mentioned above, making it the most suitable and excellent filter for small magnetic disk devices. Although the present invention has been described with reference to one embodiment,
It goes without saying that the present invention is not limited to this, and that various changes and modifications are possible, such as the shape of the filter and the shape of the protrusions provided on the sealing surface.

[Brief explanation of the drawing]

FIG. 1 shows an assembled cross section of a filter according to an embodiment of the present invention, FIG. 2 shows a perspective view of an exploded arrangement of parts, and FIG. 3 shows a 3-3 cross section in FIG. 2 and an enlarged cross-sectional view of a protrusion. 10... Filter, 11... Upper casing,
14, 15...comb tooth-like projection, 16, 17...
Projection bar, 20...material, 24...lower casing.

Claims (1)

[Scope of utility model registration request] The synthetic resin casing is formed by fitting the upper and lower parts together, and adjacent comb-like protrusions are provided on the inner surface of each side wall, and the upper and lower parts are arranged so as to interlock with each other. In a square filter in which both ends of the pleats of the material are sandwiched, and both ends of the pleats of the material are sandwiched by the fitting parts of the front and rear walls of the upper and lower casings, A crimp-seal type filter characterized by providing a continuous protrusion line along the comb-tooth shape approximately in the center of the thickness of the comb-tooth-like protrusion.