Electrical signal filter and method for manufacture of electrical signal ...

United States Patent im

Yoshie et al.

US005150087A

[11] Patent Number: [45] Date of Patent:

5,150,087 Sep. 22, 1992

[54] ELECTRICAL SIGNAL FILTER AND METHOD FOR MANUFACTURE OF ELECTRICAL SIGNAL FILTER INTERNAL CIRCUIT BOARD

[75] Inventors: Hiroto Yoshie, Sagamihara;

Hironobu Sato, Isehara, both of
Japan

[73] Assignees: Mitsumi Electric Co., Ltd., Japan;

Regal Technologies Ltd., Englewood,
Colo.

[21] Appl. No.: 619,942

[22] Filed: Not. 29, 1990

[30] Foreign Application Priority Data

Nov. 30, 1989 [JP] Japan 1-138713[U]

May 31, 1990 [JP] Japan 2-57817[U]

Oct. 27, 1990 [JP] Japan 1-126324[U]

Oct. 31, 1990 [JP] Japan 2-114604[U]

Oct. 31, 1990 [JP] Japan 2-114605[U]

Oct. 31, 1990 [JP] Japan 1-114606[U]

Oct. 31, 1990 [JP] Japan 2-114607[U]

Oct. 31, 1990 [JP] Japan 2-294877JU]

[51] Int.C1.5 H03H7/00

[52] U.S. CI 333/185; 333/167;

333/12

[58] Field of Search 333/185, 12, 167, 175,

333/176, 168, 177, 178, 179, 180, 181, 182, 183,

169, 170, 24 R

[56] References Cited

U.S. PATENT DOCUMENTS

4,451,803 5/1984 Holdsworth et al 333/12

4,701,726 10/1987 Holdsworth 333/185

4,845,447 7/1989 Holdsworth 333/167

Primary Examiner—Eugene R. Laroche

Assistant Examiner—Ali Neyzari

Attorney, Agent, or Firm—Andrus, Sceales, Starke &

Sawall

[57] ABSTRACT

An electrical signal filter in which circuit provided with filter circuits are inserted into a cylinder-shaped shield case, has a first cavity portion having an inner case. The side of one end of the inner case has the circuit boards inserted, and the side of the other end thereof is provided with one of an input side connector and an output side connector. The electrical signal filter also has a second cavity portion having a second shield case having an outer case. The side of one end of the second shield case is provided with one of an output side connector and an input side connector.

14 Claims, 17 Drawing Sheets