Global Patent Index - EP 0489467 A1

EP 0489467 A1 19920610 - System for detecting the presence in a rack of a portable unit suitable for transmitting or receiving a signal having an assigned identification number.

Title (en)

System for detecting the presence in a rack of a portable unit suitable for transmitting or receiving a signal having an assigned identification number.

Title (de)

Anwesenheitsnachweissystem in einem Regal einer tragbaren Einheit mit Fähigkeit zum Senden oder Empfangen eines eine Ausweiszahl enthaltenden Signals.

Title (fr)

Système de détection de la présence dans une étagère d'une unité portable apte à transmettre ou à recevoir un signal comprenant un numéro d'identification assigné.

Publication

EP 0489467 A1 19920610 (EN)

Application

EP 91203127 A 19911128

Priority

NL 9002677 A 19901205

Abstract (en)

In a system for detecting the presence in a rack of a portable unit suitable for transmitting or receiving a signal having an assigned identification number said portable unit comprises a detection means which detects the placing of the portable unit in, or its removal from, a compartment. If said detection means detects placing of the portable unit in a compartment the portable unit transmits a presence report signal which is received by a receiving means of a detection device of the rack in reponse to which a control circuit of the detection device stores a presence datum in a location of a memory indicating the presence of the portable unit in the rack. Removal of the presence datum out of the memory can be caused in several ways. According to one solution the portable unit detects said removal and transmits an absence report signal ARS in response to which the control circuit of the detection device removes said present datum from the memory. According to a second solution the portable unit, if placed in a compartment, transmits continuously or intermittently a hold signal HS. If the detection device of the rack does not receive the holdsignal HS during a predetermined period of time it removes the present datum. According to a third solution the compartment has a detection means, e.g. a switch, which can detect the removal of the portable unit from the compartment. If the detection means detects such removal the controle device of the rack removes the present datum out of the memory. According to a fourth solution the detection device of the rack scans each compartment in which the presence of a portable unit has been detected by transmitting a scanning signal to each of these portable units. If the detection device does not receive a response signal from a scanned portable unit within a predetermined period of time it removes the presence datum for this portable unit out of the memory. For both the first and second of said solutions the initiative for storing or removal a present datum in the memory lies with the portable unit. With both of said third and fourth solutions the initiative for storing a presence datum lies with the portable unit and the initiative for removing the presence datum out of the memory lies with the detection device of the rack. <IMAGE>

IPC 1-7

G08B 3/10; G08B 5/22; G08B 26/00

IPC 8 full level

G08B 3/10 (2006.01); G08B 26/00 (2006.01)

CPC (source: EP)

G08B 3/1075 (2013.01); G08B 26/003 (2013.01)

Citation (search report)

Designated contracting state (EPC)

DE FR GB NL SE

DOCDB simple family (publication)

EP 0489467 A1 19920610; EP 0489467 B1 19950726; DE 69111579 D1 19950831; DE 69111579 T2 19960125; NL 9002677 A 19920701

DOCDB simple family (application)

EP 91203127 A 19911128; DE 69111579 T 19911128; NL 9002677 A 19901205