Patent US4057794A successfully refreshed from Google Patents.
US4057794A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Calling aids
Assignee: National Research Development Corp UK
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Filing: 1975-04-02
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Granted: 1977-11-08
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Expires: 1995-04-02
Abstract
Abstract A pocket-size portable transmitter in an emergency call transmission system for geriatric persons has an actuator including a simple switch part such as a push button and a simple cover part movable between a normal closed position covering the switch to prevent accidental actuation and an open position exposing the switch for actuation. In a preferred system a plurality of transmitters are inductively coupled with respective receivers distributed to determine separate areas for use of the transmitters, the transmitters producing multi-element code sequence signals to avoid false alarms from outside interference, and the receivers having wired connections to a central alarm indicator assembly.
Inventors
- 👤 Karl Grossfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:57
CPC Classifications
G; G08; G08B; G08B25/00; G08B25/01; G08B25/016; G08B21/00; G08B21/02; G08B21/04; G08B25/001; G08B25/002
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
165 words
An emergency-call transmission system, comprising: a. a plurality of similar indirectly-coupled transmission sub-systems which each include a portable transmitter to be carried by an individual person at risk, and a stationary sited receiver, each said transmitter having a housing and an actuator mechanism which includes a switch part and a cover part integrally associated with said housing, said cover part being movable between a first position in which it covers the switch part and renders the same non-actuable and another position in which it exposes the switch part for actuation, each said transmitter including a transmission signal generator of multi-element code sequence form, each said receiver including a detector for said code sequence of the respective sub-system transmitter, and each said receiver being separately located to define an individual zone of effectiveness for said respective transmitter; and b. a stationary sited monitor unit including a plurality of first call indicators respectively directly connected to said receivers and operable therewith in response to said respective transmitters.
Claim 2
Dependent Claim
165 words
An emergency-call transmission system, comprising: a. a plurality of similar indirectly-coupled transmission sub-systems which each include a portable transmitter to be carried by an individual person at risk, and a stationary sited receiver, each said transmitter having a housing and an actuator mechanism which includes a switch part and a cover part integrally associated with said housing, said cover part being movable between a first position in which it covers the switch part and renders the same non-actuable and another position in which it exposes the switch part for actuation, each said transmitter including a transmission signal generator of multi-element code sequence form, each said receiver including a detector for said code sequence of the respective sub-system transmitter, and each said receiver being separately located to define an individual zone of effectiveness for said respective transmitter; and b. a stationary sited monitor unit including a plurality of first call indicators respectively directly connected to said receivers and operable therewith in response to said respective transmitters.
Claim 3
Dependent Claim
53 words
A system according to claim 1 wherein said first indicators are of visual form, said monitor unit further comprises a common audible alarm directly operably connected with each said receiver, and said system further comprises a plurality of second call indicators located adjacent and directly operably connected with respective ones of said receivers.
Claim 4
Dependent Claim
22 words
A system according to claim 1 wherein said switch part is of push button type and said cover is of snap-connection type.
Claim 5
Dependent Claim
31 words
A system according to claim 3 wherein said cover part includes an annular wall surrounding said push button, and a lid hinged to and adapted for snap-fit engagement with said wall.
Claim 6
Dependent Claim
46 words
A system according to claim 1, wherein each said transmitter includes an external casing having a clip connected thereto for supporting said casing on an article of clothing, and an elongate flexible member connected to said casing to form a loop for carriage of said casing.
Claim 7
Dependent Claim
15 words
A system according to claim 1 wherein said generator is of multi-tone code sequence form.
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) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |