| 摘要 |
<p>The fire extinguisher is portable and contains a foam liquid, expelled by a propulsive medium under pressure in a bottle. The body of the extinguisher is made from metal and coated internally with a lining of synthetic resin to avoid any corrosive effect by the foam. Equally, th ehead of the extinguisher is also made from synthetic resin. This holds the pressure bottle, a diaphragm being punctured by a pointed rod pushed down externally after removing a pin. An excess pressure safety valve is fitted in the discharge, a plunger being forced upwards to puncture another diaphragm and open the outlet.</p> |
