| 摘要 |
<p>A thermostat operating switching e.g. of an electric heater, by movements of a pressure diaphragm connected to a temp. probe bulb, opposed by a spring, has a second switch in series opening when pressure indicated by diaphragm falls below a predetermined level, to prevent continued operation of appts. in the event of breakage or leakage of detector. Pref. both switches are opened and closed by contact with pins suitably positioned on a rod pressed on diaphragm by the spring.</p> |
