US4720855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone apparatus
Assignee: Sony Corp
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Filing: 1986-02-20
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Granted: 1988-01-19
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Expires: 2006-02-20
Abstract
Abstract In a telephone apparatus used for a telephone system such that the telephone set is connected to a remote destination telephone set through telephone circuits after an ID number of a subscriber has been transmitted to the telephone company, the handset comprises a key entry section including plural dial keys, a memory section for storing the ID number and destination telephone numbers, a display section for displaying a destination telephone number corresponding to an operated dial key, and a control section for enabling a display of the ID number when the ID number is written but disabling a display of the ID number when read. Since the ID number is not displayed while being read to transmit it to the telephone company, the ID number of the subscriber is kept secret from others.
Inventors
- 👤 Kanji Ohnishi
- 👤 Hiroshi Yasuda
- 👤 Norio Numata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:44
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/66; H04M1/667; H04M1/67; H04M1/673; H04M1/26; H04M1/27; H04M1/274; H04M1/2745; H04M1/56; H04M1/27467; H04M1/72; H04M1/724
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
152 words
A telephone apparatus used for a telephone system in which the telephone apparatus is connected to a remote destination telephone through telephone circuits after an identification number for a subscriber has been transmitted to a telephone company, which comprises: (a) key entry means including plural dial keys; (b) memory means for storing the identification number and a plurality of remote destination telephone numbers both entered through the dial keys; (c) display means for displaying a remote destination telephone number corresponding to an operated dial key; and (d) control means for enabling a display of the identification number to be displayed on said displaying means when the identification number is written at a designated address of said memory means but disabling a display of the identification number on said displaying means when the identification number is read from the designated address of said memory means to transmit the number to the telephone company.
Claim 2
Dependent Claim
152 words
A telephone apparatus used for a telephone system in which the telephone apparatus is connected to a remote destination telephone through telephone circuits after an identification number for a subscriber has been transmitted to a telephone company, which comprises: (a) key entry means including plural dial keys; (b) memory means for storing the identification number and a plurality of remote destination telephone numbers both entered through the dial keys; (c) display means for displaying a remote destination telephone number corresponding to an operated dial key; and (d) control means for enabling a display of the identification number to be displayed on said displaying means when the identification number is written at a designated address of said memory means but disabling a display of the identification number on said displaying means when the identification number is read from the designated address of said memory means to transmit the number to the telephone company.
Claim 3
Dependent Claim
53 words
The telephone apparatus as set forth in claim 1, wherein the identification number is converted into a dual tone multi-frequency (DTMF) signal before being transmitted to the telephone company and further the converted signal representative of the identification number is muted without reproducing the converted signal through a speaker of the telephone apparatus.
Claim 4
Dependent Claim
55 words
The telephone apparatus as set forth in claim 1, wherein the identification number is converted into a dual tone multi-frequency (DTMF) signal before being transmitted to the telephone company and further a sound different from that corresponding to the dial keys of the key entry means is produced through a speaker of the telephone apparatus.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-18 | 1991-07-20 | 1992-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-18 | 1995-07-20 | 1996-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-18 | 1999-07-20 | 2000-01-19 | $7700.00 | Window Closed / Lapsed |