Child proximity detector

• US 5,646,593 A
• Filed: 04/26/1995
• Issued: 07/08/1997
• Est. Priority Date: 02/02/1995
• Status: Expired due to Fees

• Current Assignee: Hewlett Electronics
• Original Assignee: Hewlett Electronics
• Inventors: Hewlett, William E., Hughes, Michael, Clarke, Ian
• Primary Examiner(s): Mullen, Thomas
• Assistant Examiner(s): Lee, Benjamin C.
• Application Number:
  US08/429,142
• Time in Patent Office: 804 Days
• Field of Search: 340/573, 340/539, 340/505, 340/572, 340/531, 340/534, 340/571, 340/568, 340/540, 340/825.36
• US Class Current: 340/573.1
• CPC Class Codes: G08B 21/0222 Message structure or message content, e.g. message protocol
• CPC Class Codes: G08B 21/023 Power management, e.g. system sleep and wake up provisions
• CPC Class Codes: G08B 21/0286 Tampering or removal detection of the child unit from child or article

Abstract

A child proximity detection unit includes two transceivers which communicate messages with one another. Only a properly authorized parent can attend a message to the child unit. However, a properly authorized parent can authorize another parent to adopt a child unit.

Claims

1. A proximity detector comprising:

a first transceiver unit, configured to have a parent identification number; and

a second transceiver unit configured to have a child identification number;

said first transceiver unit including a message producing structure which produces a polling message which includes identification numbers therein to the second transceiver unit, and which monitors responses from said second transceiver unit to determine if said second transducer unit is further than a predetermined distance therefrom to produce an alarm;

said second transceiver unit including a processor which investigates said polling message to determine if said polling message includes a parent identification number and a child identification number which each match a predetermined criteria, and transmitting a response only if so, and wherein said second transceiver unit also includes an element for detecting that said first transceiver unit is more than a second predetermined distance therefrom, and producing an alarm based on said detecting.