Cable signal interference suppressor

• US 5,334,955 A
• Filed: 03/01/1993
• Issued: 08/02/1994
• Est. Priority Date: 03/01/1993
• Status: Expired due to Fees

• Current Assignee: Edward F. Strnad
• Original Assignee: Edward F. Strnad
• Inventors: Strnad, Edward F.
• Primary Examiner(s): GENSLER, PAUL L
• Application Number:
  US08/024,450
• Time in Patent Office: 519 Days
• Field of Search: 333/12, 333/181, 333/185, 336/92, 336/175, 336/176
• US Class Current: 333/12
• CPC Class Codes: H03H 1/0007 of radio frequency interference filters
• CPC Class Codes: H03H 2001/0028 RFI filters with housing divided in two bodies

Abstract

A signal filter is disclosed herein for the filtering of electromagnetic interference carried by an electrical conductor having a housing enclosing a core of soft ferrite composition with a weak magnetic field impressed upon it adapted to be placed about the electrical conductor having a directional signal flow within the electromagnetic generation pattern of the conductor to absorb signal interference emission accompanying a transmitted signal. The housing has an indicator identifying magnetic flux directional polarity of the core. The housing may include a retaining strap or securement prongs that engage with the cable to maintain the filter in place.

Claims

1. In a polarized cable signal interference filter of electromagnetic interference emitted from a polarized electrical cable having a directional signal flow, the combination comprising:

a housing;

a core of weakly (less than 50 milligauss) magnetized ferrite composition enclosed by said housing;

retaining means carried on said housing for securement with said cable;

said housing critically disposed on said cable to place said core in effective relationship to absorb extraneous and undesired electromagnetic waves present on said cable;

said housing is of two portion construction having a hinge means movably connecting said portions together;

each housing portion has a semicircular recess occupied by said weakly magnetized ferrite composition when said portions are open and said semicircular portion recesses define an open-ended central circular bore when said portions are closed together;

means carried on said housing for removably retaining and restraining said cable on said housing;

snap-lock fastener means cooperatively carried on said housing portions for detachably connecting said housing portions together in an operative position about said cable;

said snap-lock fastener means includes a latch disposed on one housing portion and a detent disposed on the other housing portion;

said retaining and restraining means includes prong means carried on opposite ends of said housing engageable with the exterior of said cable in an interference relationship to retain said cable in its position on said housing;

said core of weakly magnetized ferrite composition comprising a pair of semicircular ferrite cores wherein each of said housing portions enclose one semicircular ferrite core whereby a conformal recess is defined on each housing portion constituting said open-ended circular bore receiving said cable when said housing portions are together in said operative position about said cable;

orientation indicia carried on said housing identifying magnetic flux directional polarity (i.e., North-to-South) of said magnetized ferrite core;

orientation with the directional signal flow in said cable providing noise suppression filtering of the electrical signal flow carried by said cable in coordination with said orientation indicia.

2. The invention as defined in claim 1 wherein:

said orientation indicia is a directional or polarity marker on the exterior of said housing pointed at a selected end of said housing augmenting said filter'"'"'s ability to absorb electromagnetic field forces.

3. An improved interference filter comprising:

an electrical cable having an assumed directional signal flow;

a filter detachably carried on said electrical cable having a core of weakly pre-magnetized ferrite material of given polarity enclosed in a housing having an exterior surface;

a visual marking carried on said housing exterior for properly orienting the magnetic polarity of said ferrite material; and

said cable and filter are in harmonizing polarity orientation so that said filter absorbs signal interference accompanying said cable signal flow.