Refrigerant dryer service valve

Claim 1

A service valve in combination with a refrigerating system dryer, said dryer having arcuate converging end wall surfaces, the improvement comprising: a generally cylindrical centally bored housing having wrench flats intermediate its ends and a diametrically reduced periphery forming a relatively thin wall having a free end surface at one end portion, said housing being counterbored from its thin wall end to form an annular tapered shoulder intermediate its ends facing toward said thin wall portion, said housing having external threads extending between said wrench flats and said thin wall portion, the other end portion of said housing being diametrically reduced and connected in end abutting relation with one arcuate end wall of said dryer by brazing; a tubular core, having a length slightly greater than the spacing between the free end surface of said housing thin wall portion and said other end of said housing, cooperatively received coaxially by the bore of said housing, said core having a diametrically reduced tapered end portion converging toward the tubular member wall to be pierced, said tapered end portion terminating in a beveled end surface forming a wall piercing tip, said core having an external beveled surface intermediate its ends forming an annular shoulder facing toward the wall piercing tip, said core having a diametrically reduced peripheral portion adjacent its end opposite said line piercing tip forming an annular shoulder adjacent the housing thin wall portion, said core having internal threads at its end portion opposite said wall piercing tip and having a seat formed on its inner Wall surface at the inner limit of the threads; an air valve sealing with the seat in said core; and, a cap engaging the threads on said housing and axially moving said core toward said tubular member wall in a wall piercing action while simultaneously seating and sealing said core within said housing.