US4899135A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Child monitoring device
Assignee: Individual
•
Filing: 1988-12-05
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Granted: 1990-02-06
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Expires: 2008-12-05
Abstract
Abstract An ultra-sonic or radio-frequency monitoring system comprising a transmitting unit carried by the child and a receiving unit carried by the child's guardian that will alert the guardian when the child strays beyond a predescribed distance, is abducted or falls into water.
Inventors
- 👤 Mehdi Ghahariiran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:38
CPC Classifications
G; G08; G08B; G08B21/00; G08B21/02; G08B21/0202; G08B21/0227; G08B21/18; G08B21/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
180 words
A range sensitive system employing two or more ultra sonic transceivers to monitor the activities of a child, children or individuals, carrying transceivers monitored by a base transceiver carried by a guardian wherein the improvement comprises: a, the transceivers operating in ultra sonic frequency spectrum; p1 b, the child's transceiver transmitting a constant signal which is received by the guardian's transceiver which converts the signal into an audio tone; c, the guardian's transceiver having a threshold receiving circuit adjustable to correlate a prescribed distance from the transceiver carried by the child; d, the loss of a signal from the child's transceiver energizing an audio generator in the guardian's tranceiver; e, a signal from the guardian's transceiver energizing an audio tone transmitter in the child's transceiver; f, the child's transceiver carried in a holster having means to open the transmission circuit if the transceiver is removed from the holster; and, g, the child's transceiver in the holster being attached to the child by a support belt having means to open the transmission circuit if the belt is removed from the child.
Claim 2
Dependent Claim
180 words
A range sensitive system employing two or more ultra sonic transceivers to monitor the activities of a child, children or individuals, carrying transceivers monitored by a base transceiver carried by a guardian wherein the improvement comprises: a, the transceivers operating in ultra sonic frequency spectrum; p1 b, the child's transceiver transmitting a constant signal which is received by the guardian's transceiver which converts the signal into an audio tone; c, the guardian's transceiver having a threshold receiving circuit adjustable to correlate a prescribed distance from the transceiver carried by the child; d, the loss of a signal from the child's transceiver energizing an audio generator in the guardian's tranceiver; e, a signal from the guardian's transceiver energizing an audio tone transmitter in the child's transceiver; f, the child's transceiver carried in a holster having means to open the transmission circuit if the transceiver is removed from the holster; and, g, the child's transceiver in the holster being attached to the child by a support belt having means to open the transmission circuit if the belt is removed from the child.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |