Laboratory glassware taper connector system with retainer and backup seal

Claim 1

In a laboratory glassware taper connector system including first and second parts to be connected having respectively tapered male and female end portions in mating engagement to form a joint, said first part having an annular shoulder at the large end of the taper thereon, the improvement comprising a male screw thread formed on the end portion of said second part, an O-ring encircling said first part in engagement with said shoulder, and a cap having a female screw thread in the rim thereof adapted to mate with said male screw thread, said cap having a central hole in the top thereof leaving an annular flange extending inwardly from the top of said rim and engaging said O-ring, the diameter of said hole being approximately equal to but not less than the outside diameter of said shoulder, the arrangement being such that when said cap is screwed tightly upon said male thread the O-ring is compressed and presses against said shoulder to urge and maintain said male taper into tight engagement with said female taper of said connector system.