发明名称 |
Coating responsive material condition monitoring system |
摘要 |
A multiple set point material condition monitoring system is responsive both to the level of material with respect to a sensor and the extent of material coating which has accumulated on the sensor. The system provides an output when a predetermined coating thickness has been exceeded, so that the sensor may be cleaned before the coating can accumulate to the extent where a false level output is generated. The systems include three electrode guarded sensors, a bridge comparing the sensor output with a reference, and a bridge reference which is automatically and repeatedly caused to assume a sequence of values corresponding to material condition set points, one of which causes an output when a predetermined coating thickness has occurred and another of which generates a level output. In one embodiment, separate outputs are provided corresponding to each set point. In another embodiment, a single tri-state output is responsive to both set points.
|
申请公布号 |
US5539670(A) |
申请公布日期 |
1996.07.23 |
申请号 |
US19940208928 |
申请日期 |
1994.03.10 |
申请人 |
DREXELBROOK CONTROLS, INC. |
发明人 |
MALTBY, FREDERICK L.;KRAMER, L. JONATHAN;PETERSEN, STEVEN R. |
分类号 |
G01B7/06;G01F23/00;G01F23/26;(IPC1-7):G01F23/26 |
主分类号 |
G01B7/06 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|