Dry sprinkler with non-load-transmitting sealing arrangement

摘要

In the representative embodiments of the invention described herein a dry sprinkler for a fire protection system has a pair of coaxial tubes arranged one inside the other and a plug which seals a fluid passageway formed in a cap at the inlet end of the outer tube to prevent fluid in a supply pipe of the fire protection system from flowing into the sprinkler when the plug is in the passageway. The plug is retained in the passageway against fluid pressure in the supply pipe by a retaining mechanism which releases the plug for automatic expulsion from the passageway by the fluid pressure in the supply pipe when the inner tube moves longitudinally from a first position to a second position.