muschett

Claim 1

IN A POP-UP SPRINKLER, A POP-UP STANDPIPE INCLUDING AN OUTER ERECT TUBULAR SECTION AND AN INNER ERECT TUBULAR SECTION TELESCOPICALLY RECEIVED IN SAID OUTER SECTION, SAID OUTER TUBULAR SECTION HAVING AN INWARDLY DIRECTED FIRST FLANGE AT ITS UPPER END DEFINING AN OPENING, SAID INNER TUBULAR SECTION HAVING A CONTINUOUS OUTWARDLY EXTENDING PISTON SECOND FLANGE AT ITS LOWER END AND AN OUTWARDLY EXTENDING CONTINUOUS BEARING SEALING CENTERING AND STABILIZING THIRD FLANGE SPACED FROM AND ABOVE SAID PISTON SECOND FLANGE, THE RADIAL CLEARANCE BETWEEN THE INNER TUBULAR SECTION AND THE OPENING IN THE FIRST FLANGE AND BETWEEN THE OUTER TUBULAR SECTION AND THE SECOND FLANGE BEING SLIDING CLEARANCES PROVIDING ANNULAR SPACES OF SUFFICIENTLY LARGE RADIAL DIMENSIONS TO PERMIT DURING ERECTION OF THE STANDPIPE A FLUSHING ACTION OF WATER THERETHROUGH AND THE PASSAGE OF FOREIGN MATERIAL THAT MAY FIND ITS WAY INTO THE INTERIOR OF THE STANDPIPE AND THE SPACE BETWEEN THE TWO TUBULAR SECTIONS, THE RADIAL CLEARANCE BETWEEN THE THIRD FLANGE AND THE OUTER TUBULAR SECTION BEING IN EXCESS OF A SLIDING CLEARANCE AND SUPPLYING A WIDER RADIAL SPACE THAN THE FIRST MENTIONED ANNULAR SPACES FOR FLUSHING ACTION AND NON-SCORING PASSAGE OF FOREIGN MATERIAL THERETHROUGH DURING THE ERECTION OF THE STANDPIPE, SAID THIRD FLANGE ENGAGING THE FIRST FLANGE IN THE ERECTED POSITION OF THE STANDPIPE TO CENTER THE INNER TUBULAR SECTION IN ITS ERECTED POSITION, TO FORM A SEAL WITH THE FIRST FLANGE, AND IN CONJUNCTION WITH THE COOPERATION BETWEEN THE SECOND FLANGE AND THE OUTER TUBULAR SECTION TO STABILIZE THE STANDPIPE IN ITS ERECTED POSITION.