DE8912509U1 - Improved high frequency isolation device for a high frequency signal distributor - Google Patents

Description

SIGNAL CATV SYSTEM INC., No. 34, Fu Hsing Rd., Kee Lung City, Taiwan, R.O.C.

Improved high frequency isolation device for a high frequency signal distributor

The present invention relates to a high frequency isolation device for a high frequency signal distributor.

To prevent the leakage of radiation, the isolation device consists of a metallic housing that tightly encloses a high frequency signal distributor. To enable the high frequency signal distributor to be installed in the housing, the housing is divided into two separate parts, namely a cover and a housing body. Since the connection between the cover and the housing body

1338

Office Bremen / Bremen Office:

Hollerallee 32, D-2800 Bremen 1

P.O.Box 10 7127

• Telephone: (0421) '349071

Telex: 244 958 bopatd

Fax: (0421) 34 69 68 CCITTH + III

Cables: Diagram Bremen

Deutsche Bank, Bremen
(Bank code 290 700 50) 111 2002

Bremer Bank, Bremen · · · (Bank code 290*800 It)J UK) 1*44 90p!

Office Munich/Munich Office (now

Widenmayerstrasse 4, D-8000 Munich 22

P.O. Box 22 01 37

Telephone: (089)* 22 33 11

Telex: 524 282 forbod

Fax: (089) 2215 69 CCITTII+ 111

obank, Munich
ftOrf 20001)6400 194333

PSchA Hamburg

(Bank code 200 10020) 126083-202

BOEHMERT & BOEHMERT - 2 -

represents the only exit for the high frequency signals to escape, the insulating effect depends largely on the tight engagement of the joint between the cover and the housing body. Referring to Fig. 3, a conventional radio wave insulating device comprises a cover 2 and a housing body 3 made of aluminum, in order to ensure a tight engagement between the cover 2 and the housing body 3, the thickness of the walls of the housing body 3 becomes thinner near its edge, thereby defining a peripheral ledge 31 on which a plurality of triangular teeth 32 are provided. The width (W) and length (L) of the interior of the housing body at the level of the ledge are correspondingly slightly smaller than the width (W') and length (L') of the cover 2. Therefore, when the cover 2 is pressed into engagement with the housing body 3, the tip of each tooth is slightly deformed and a compressive force is generated by the deformed tooth which presses against the side of the cover 2 adjacent to each tooth (shown by arrows), thereby holding the cover 2 firmly in place.

This conventional insulating device suffers from two drawbacks. First, the housing body 3 may bulge outward under the action of the teeth arranged perpendicularly on its four sides, causing leaks between the cover 2 and the housing body 3 and deteriorating the insulating effect of the device. Second, once the housing body 3 is removed from the cover 2 (e.g., to repair or replace the high frequency signal distributor therein), it can no longer be used because the tips of the teeth have become blunt and can no longer exert a force on the cover 2 to hold the latter in place when it is reused.

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BOEHMERT & BOEHMERT

The invention is therefore based on the object of providing an improved insulating device which avoids the aforementioned disadvantages.

According to the invention, the ledge is provided with a plurality of projections and the cover is provided with a plurality of corresponding notches. Each projection must slightly exceed its ^associated notch so that a holding force is generated due to the deformation of the projection in the notch. Since the force acts parallel and not perpendicular to the cover side, the housing body does not bulge, thus ensuring good insulation .

Further advantages and features of the invention will become apparent from the following description of an embodiment of the present invention, which is explained in more detail with reference to the accompanying drawings.

Fig. 1 is an exploded view of a high frequency isolation device according to the invention;

Fig. 2 is a plan view of the device of Fig. 1, illustrating the force due to the deformation of the projections in the notches;

Fig. 3 is an exploded view of a conventional insulating device; and

Fig. 4 is a plan view of the conventional isolating device of Fig. 3, illustrating the force due to the deformation of the teeth.

Referring to Fig. 1, an insulating device according to the invention comprises a cover 2a and a housing body

BOEHMERT & BÖHMERT

3a. The thickness of the side walls of the housing body 3a becomes thinner near its edge, thereby defining a ledge 31a. This corresponds to the prior art as shown in Fig. 3. As mentioned above, the characteristic feature of this invention is that a plurality of projections 32a are provided on the ledge 31a and a plurality of corresponding notches 22a on the four sides of the cover 2a. The dimensions of the cover 2a of the housing body 3a, the notches 22a and the projections 32a must be such that when the cover 2a is inserted in place in the housing body 3a, no force perpendicular to the sides but forces parallel to the sides of the cover 2a are generated. A projection 32a must slightly exceed its associated notch 22a in size so that it can be slightly deformed in the notch 22a.

Referring to Fig. 2, arrows indicate the forces resulting from the deformation of the projections 32a in their associated notches. Since the forces are all parallel to the sides of the cover 2a, they merely reinforce the engagement of the cover 2a and the housing body 3a and do not cause the housing body 3a to bulge.

Preferably, the projections 32a do not extend to the edge of the cornice to ensure better insulation.

BOEHMERT & BOEHMERT

S3040

List of reference symbols

2 cover 2 2a cover 2a 3 Housing body 3 3a Housing body 3a 22a Notches 22a 31 Sims 31 31a Sims 31a 32 Teeth 32 32a Projections 32a

tilt ti

Claims (1)

SIGNAL CATV SYSTEM INC., No. 34, Fu Hsing Rd., Kee Lung City, Taiwan, ROC Improved high frequency isolation device for a high frequency signal distributor Claim A high frequency insulation device for a high frequency signal distributor in the form of a metallic housing with a cover and a housing body, the thickness of the side walls of the housing body decreasing near the edge thereof and thereby defining a ledge, characterized in that a plurality of projections (32a) are formed on said ledge (31a) and the cover (2a) has a plurality of notches (22a) corresponding to the projections (32a), Office Bremen / Bremen Office: Office Munich/Munich Office murPatentanwalt·:): Hollerallee 32, D-2800 Bremen 1 Widenmayerstraße 4, D-8000 Munich 22 P.O.Box 10 7127 P.O.Box 22 0137 • Telephone: (0421) *34 9071 Telephone: (089)*2233 11 Telex: 244 958 bopat d Telex: 524 282 forbo d Fax: (0421)346968CCITTII + IH Fax: (089)2215 69 CCITTII+ III Cables: Diagram Bremen Cables: Telepatent Munich Deutsche Bank, Bremen Bremer Bank, Bremen · ·· ···■ Hygobin^k, Munich PSchA Hamburg (Bank code 290 700 50) 1&Pgr; 2002 (bank code 290|8O0 &Lgr;),&Agr;» IjH 900· · · · _t JBL^qt^OO 01) 6 400 194 333 (bank code 200100 20) 1260 83-202 BOEHMERT & BOEHMERT
- 2 - wherein the cover (2a), the housing body (3a), the projections (32a) and the notches (22a) are designed such that ■ when the cover (2a) is inserted in place in the housing body (3a), each projection (32a) is slightly deformed in the corresponding notch (22a), thereby generating a force which acts parallel to the side of the cover (2a) on which the notch (22a) is arranged. I