wherein the key telephone sets are star-connected to a central unit by a limited number of lines

Industry

CPC
H04M9/007

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Parent Industries

HELECTRICITY H04Electric communication H04MTELEPHONIC COMMUNICATION H04M9/00Interconnection arrangements not involving centralised switching

Current Industry

H04M9/007wherein the key telephone sets are star-connected to a central unit by a limited number of lines

Industries

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Patents Grantslast 30 patents

Information Patent Grant
Interface device for intercom access control systems
- Patent number 12,206,826
- Issue date Jan 21, 2025
- Amazon Technologies, Inc.
- Aaron Lung
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Intercom network and terminal therefor
- Patent number 10,904,683
- Issue date Jan 26, 2021
- RIEDEL COMMUNICATIONS INTERNATIONAL GMBH
- Thomas Riedel
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Speech station for intercom network
- Patent number 10,284,698
- Issue date May 7, 2019
- RIEDEL COMMUNICATIONS INTERNAIONAL GMBH
- Hubert Sieben
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Trunk circuit with loop length gain equalization
- Patent number 4,887,293
- Issue date Dec 12, 1989
- Mitel Corporation
- Gerald Molnar
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,782,514
- Issue date Nov 1, 1988
- Iwatsu Electric Co., Ltd.
- Hironobu Oshikata
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,763,354
- Issue date Aug 9, 1988
- Iwatsu Electric Co., Ltd.
- Hiroshi Fukushima
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,759,055
- Issue date Jul 19, 1988
- Tamura Electric Works, Ltd.
- Senji Okumura
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Telephone system
- Patent number 4,727,578
- Issue date Feb 23, 1988
- Trillium Telephone Systems Inc.
- Gerald Molnar
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Apparatus for locating programs resident on a cartridge of a cartri...
- Patent number 4,703,416
- Issue date Oct 27, 1987
- American Telephone and Telegraph Company
- Joseph A. Crupi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Communication system having voice and data capability
- Patent number 4,685,123
- Issue date Aug 4, 1987
- American Telephone and Telegraph Company
- Richard Y. Hsia
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Extension ringing arrangement key telephone system
- Patent number 4,660,219
- Issue date Apr 21, 1987
- Nitsuko Limited
- Kinzi Tanaka
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Two wire voice and data subscriber loop
- Patent number 4,608,686
- Issue date Aug 26, 1986
- Mitel Corporation
- John A. Barsellotti
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Apparatus for enhancing the use of electromechanical key telephone...
- Patent number 4,607,144
- Issue date Aug 19, 1986
- Telecomputer Corporation, Ltd.
- Amiram Carmon
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Terminal interface connecting terminal unit having central office l...
- Patent number 4,564,724
- Issue date Jan 14, 1986
- Kabushiki Kaisha Toshiba
- Yasunobu Nakayama
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Programmable cartridge telephone communication system
- Patent number 4,506,346
- Issue date Mar 19, 1985
- AT&T Bell Laboratories
- Joseph M. Bennett
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system and method of setting operating data in the ke...
- Patent number 4,491,693
- Issue date Jan 1, 1985
- Tokyo Shibaura Denki Kabushiki
- Yoshikazu Sano
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,412,102
- Issue date Oct 25, 1983
- Nippon Telegraph & Telephone
- Seiki Ogawa
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Electronic key telephone set circuit for permitting dialing during...
- Patent number 4,392,024
- Issue date Jul 5, 1983
- Nitsuko Limited
- Tsuyoshi Shinoi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system with multiple processor control
- Patent number 4,383,137
- Issue date May 10, 1983
- Tamura Electric Works, Ltd.
- Chuta Aikawa
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,347,409
- Issue date Aug 31, 1982
- Nippon Telegraph & Telephone Public Corporation
- Seiki Ogawa
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Electronic key telephone systems
- Patent number 4,338,495
- Issue date Jul 6, 1982
- TIE/Communications, Inc.
- Alan Bloch
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Telephone system
- Patent number 4,327,256
- Issue date Apr 27, 1982
- The General Electric Company Limited
- Stephen J. Crooks
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Multiple line telephone instrument
- Patent number 4,315,110
- Issue date Feb 9, 1982
- International Telephone & Telegraph Corporation
- James M. Davis
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Electronic key telephone system with bi-directional serial data str...
- Patent number 4,292,474
- Issue date Sep 29, 1981
- OKI Electronics of America, Inc.
- Wilfred L. Morrell
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Speech channel switching networks suitable for use in combination w...
- Patent number 4,292,476
- Issue date Sep 29, 1981
- Nippon Telegraph & Telephone Public Corporation
- Kazuyuki Yamamoto
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Communication system tracking arrangement
- Patent number 4,291,199
- Issue date Sep 22, 1981
- Bell Telephone Laboratories, Incorporated
- Wayne Densmore
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone systems
- Patent number 4,280,022
- Issue date Jul 21, 1981
- Iwasaki Tsushinki Kabushiki Kaisha
- Koichi Sekiguchi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Office line connection circuit during service interruptions in key...
- Patent number 4,260,857
- Issue date Apr 7, 1981
- Nippon Tsushin Kogyo KK
- Tsuyoshi Shinoi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Electronic key telephone system
- Patent number 4,236,049
- Issue date Nov 25, 1980
- Nippon Electric Co., Ltd.
- Ryoichi Tanihata
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Key telephone system
- Patent number 4,234,765
- Issue date Nov 18, 1980
- Iwasaki Tsushinki Kabushiki Kaisha
- Kouichi Sekiguchi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE

Patents Applicationslast 30 patents

Information Patent Application
Interface Device for Intercom Access Control Systems
- Publication number 20240098187
- Publication date Mar 21, 2024
- AMAZON TECHNOLOGIES, INC.
- Aaron Lung
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Application
SPEECH STATION FOR INTERCOM NETWORK
- Publication number 20190166239
- Publication date May 30, 2019
- Hubert SIEBEN
- H04 - ELECTRIC COMMUNICATION TECHNIQUE

wherein the key telephone sets are star-connected to a central unit by a limited number of lines

Industry

Parent Industries

Current Industry

Patents Grantslast 30 patents

Interface device for intercom access control systems

Intercom network and terminal therefor

Speech station for intercom network

Trunk circuit with loop length gain equalization

Key telephone system

Key telephone system

Key telephone system

Telephone system

Apparatus for locating programs resident on a cartridge of a cartri...

Communication system having voice and data capability

Extension ringing arrangement key telephone system

Two wire voice and data subscriber loop

Apparatus for enhancing the use of electromechanical key telephone...

Terminal interface connecting terminal unit having central office l...

Programmable cartridge telephone communication system

Key telephone system and method of setting operating data in the ke...

Key telephone system

Electronic key telephone set circuit for permitting dialing during...

Key telephone system with multiple processor control

Key telephone system

Electronic key telephone systems

Telephone system

Multiple line telephone instrument

Electronic key telephone system with bi-directional serial data str...

Speech channel switching networks suitable for use in combination w...

Communication system tracking arrangement

Key telephone systems

Office line connection circuit during service interruptions in key...

Electronic key telephone system

Key telephone system

Patents Applicationslast 30 patents

Interface Device for Intercom Access Control Systems

SPEECH STATION FOR INTERCOM NETWORK