| 摘要 |
When a filter functions normally, the mechanical resistance of a diaphragm 37g, Fig. 1, (not shown), opposes its deformation, but when the pressure difference between duct 5g (joining the filter inlet to the region below the diaphragm) and duct 6g (joining the filter outlet to the region above the diaphragm) exceeds a given value the diaphragm deforms until it touches a terminal 58 above it. Such touching closes a warning circuit through diaphragm and terminal. In Fig. 2 (not shown) the terminal is replaced by a bimetallic strip so that excess pressure difference due only to high viscosity caused by low temperature of the liquid, e.g. oil, being filtered will not operate the device. |
