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US4899135A Expired / Lapsed US ⏱️ 0.0 years remaining

Child monitoring device

Assignee: Individual
•
Filing: 1988-12-05
•
Granted: 1990-02-06
•
Expires: 2008-12-05
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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.

References Cited (Backward Citations)

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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

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