Adjustable drop sprig for a fire sprinkler system

Claim 1

IN A FIRE SPINKLER SYSTEM OF THE WET SYSTEM TYPE INCLUDING A CONDUIT PIPE FOR CARRYING WATER AND THE LIKE AND WITH SAID PIPE BEING ARRANGED ABOVE THE CEILING PANEL OF A ROOM OF A BUILDING, AN ADJUSTABLE DROP SPRIG COMPRISING AN UPPER PIPE CONNECTED ADJACENT THE UPPER END THEREOF TO SAID FIRST MENTIONED PIPE AND DEPENDING THEREFORM, SAID UPPER PIPE BEING OPEN ADJACENT THE LOWER END THEREOF, A LOWER PIPE SMALLER IN DIAMETER THAN SAID UPPER PIPE AND HAVING ITS UPPER END OPEN AND TELESCOPICALLY RECEIVED IN THE LOWER END OF SAID UPPER PIPE, A VALVED SPRINKLER HEAD CONNECTED TO SAID LOWER PIPE ADJACENT THE LOWER END THEREOF, SAID SPRINKLER HEAD INCLUDING MEANS RESPONSIVE TO HEAT FOR OPENING SAID HEAD FOR PASSAGE OF WATER THERETHROUGH, SAID LOWER PIPE BEING RECTILINEARLY MOVABLE RELATIVE TO SAID UPPER PIPE TO POSITION SAID SPRINKLER HEAD AT A DESIRED POSITION, SAID LOWER PIPE HAVING A SHOULDER ADJACENT THE UPPER END THEREOF, SEALING MEANS FITTED AGAINST SAID SHOULDER AND EXTENDING OUTWARD-