EP 0099729 A1 19840201 - Suspended particle detector.
Title (en)
Suspended particle detector.
Title (de)
Detektor für suspendierte Teilchen.
Title (fr)
Détecteur pour des particules suspendues.
Publication
Application
Priority
GB 8220406 A 19820714
Abstract (en)
A suspended particle detector includes a housing (1,2) containing a radiation source (3) which shines radiation across the interior of the housing (1,2), a first radiation sensor (5) arranged to receive radiation scattered from the wall (1) of the housing (1,2) and radiation scattered from particles suspended in the housing (1,2) and to produce a first signal indicative of the total intensity of radiation incident on it. A second sensor (4) is arranged to produce a second signal indicative of the intensity of the radiation source (3). The detector also includes a signal combining circuit arranged to combine the two signals in opposition to produce a composite signal and the detector is constructed so that the composite signal has a first polarity when the density of suspended particles in the housing is less than a predetermined pressure or value and the opposite polarity when the said density is greater than the threshold value. A logic unit is arranged to detect when the polarity of the composite signal reverses and then to produce an alarm signal.
IPC 1-7
IPC 8 full level
G01N 21/53 (2006.01); G08B 17/10 (2006.01); G08B 17/107 (2006.01)
CPC (source: EP)
G08B 17/107 (2013.01); G08B 17/113 (2013.01)
Citation (search report)
- [X] US 3723747 A 19730327 - STEELE D
- [Y] DE 2856259 B1 19791220 - CERBERUS AG
- [A] EP 0015007 A1 19800903 - HEKATRON GMBH [DE]
Designated contracting state (EPC)
AT BE CH DE FR IT LI LU NL SE
DOCDB simple family (publication)
EP 0099729 A1 19840201; DK 139384 A 19840229; DK 139384 D0 19840229; ES 524120 A0 19840616; ES 8405983 A1 19840616; FI 841014 A0 19840313; FI 841014 A 19840313; GB 2123548 A 19840201; GB 2123548 B 19850904; IL 69222 A0 19831130; JP S59501283 A 19840719; NO 840972 L 19840313; WO 8400429 A1 19840202
DOCDB simple family (application)
EP 83304076 A 19830713; DK 139384 A 19840229; ES 524120 A 19830714; FI 841014 A 19840313; GB 8220406 A 19820714; GB 8300171 W 19830713; IL 6922283 A 19830714; JP 50241383 A 19830713; NO 840972 A 19840313