| 摘要 |
A condition responsive apparatus is provided including a pressure gauge having a Bourdon tube expandable in response to an external pressure. In the preferred embodiment, an optical coupler, including a solid state light source and a detector, is mounted in proximity to a vane attached to the Bourdon tube. As the Bourdon tube flexes with increased pressure, the vane passes between the light source and the detector, thus blocking the radiation from the light source. The detector includes a Darlington amplifier which forms part of a voltage divider network for connecting an output signal from the Darlington amplifier to a pulse generating circuit. In operation, when the vane connected to the Bourdon tube passes between the light source and the detector, the pulse generating circuit responds to an increased voltage across the output of the voltage divider and is thus triggered to turn on a control transistor. The control transistor serves to turn on a power transistor for controlling an alarm or other control element.
|
