Oil filters for jet-engines or high power Diesel engines have to be monitored for clogging. Clogged filters can cause severe malfunction of an engine through excessive wear and even complete damage of the engine. The condition of the filter is typically monitored by measuring a pressure differential between the inlet and the outlet port of the oil filter. A difference in oil pressure between these two ports indicates restricted flow of the oil through the filter. In this case the engine has to be serviced and the filter replaced. However, a pressure differential can also be caused by increased oil viscosity at low temperatures. The sensor will indicate the clogged condition with the filter being perfectly intact. These 'false alarms' result in unnecessary maintenance labor and waste of filters. To avoid these situations, a sensor-actuator has been developed, which compensates for increased oil viscosity at low temperatures through the use of a Ni-Ti shape memory spring.
Magnetically biased shape memory actuator for clogging indicators
Vormagnetisierter, formspeichernder Schalter zur Anzeige verstopfter Filter
1992
4 Seiten, 5 Bilder, 1 Tabelle, 2 Quellen
Aufsatz (Konferenz)
Englisch