Quick disconnect pressure cap

Abstract

A closure for the end of a male quick disconnect fluid coupling has an innal plug that displaces the plug normally provided in the male quick disconnect coupling, and the closure also has an outer plug wall with balls that can be radially cammed inwardly by a rotatable sleeve on the closure.

What is claimed is: 
     
       1. The combination comprising a male fluid coupling portion, said fluid coupling portion having an annular shaped end portion that includes an external surface of revolution defining an outwardly facing annular groove, said annular fluid coupling end portion including an internal surface of revolution that includes an inwardly facing annular groove, an O-ring seal provided in said inwardly facing groove, a ball retaining plug having an inner portion and an outer annular wall cooperating with said inner portion thereof to define an annular slot for receiving the annular shaped male coupling end portion, at least three ball elements provided in radially extending openings in said outer wall of said plug, a ball biasing sleeve threadably received on said plug for axial movement thereon, said sleeve having an annular camming surface for biasing said balls radially inwardly of said openings as said sleeve is threaded in one axial direction, said plug inner portion having an external cylindrical surface of such a diameter that the O-ring seals against it as said sleeve is so threaded on said plug. 
     
     
       2. A pressure cap adapted for use with a male fluid coupling portion wherein the male coupling is of annular shape and has an external surface of revolution that includes an outwardly facing annular groove spaced from the end of the male coupling, and an internal surface of revolution that includes an inwardly facing annular groove fitted with an O-ring seal, the improvement comprising a closure for this male coupling portion which closure includes: a plug having an inner portion adapted to be received inside the male coupling portion, said plug having an outer annular wall cooperating with said inner portion to define an annular slot for receiving the annular shaped coupling end portion;   ball elements provided for limited radial movement in openings defined by said outer wall of said plug; and   a sleeve threadably received on said plug for axial movement thereon, said sleeve having an annular camming surface or biasing said balls radially inwardly of said openings in said outer wall of said plug as said sleeve is threaded in one axial direction, said plug inner portion having an external cylindrical surface of such a diameter that the O-ring seals against it as said sleeve is so threaded on said plug.   
     
     
       3. The combination according to claim 2 wherein said openings in said plug outer wall are tapered so that the inner radial ends of said openings are slightly smaller than the ball diameter, and so that the outer ends of said openings are somewhat greater than said ball diameter. 
     
     
       4. The combination according to claim 3 wherein said sleeve includes a generally tubular portion, one end of which defines said camming surface, and a generally first cylindrical knurled portion at the opposite end of said tubular portion, which first knurled portion having a female thread under the first knurled portion, said plug including a longitudinal portion opposite said plug inner portion having a male thread to engage said female thread underneath the first knurled portion of said tubular portion. 
     
     
       5. The combination according to claim 4 wherein said ball retaining plug also defines a second knurled surface so that axial movement of said plug can be achieved by gripping the first and second knurled portions and rotating one with respect to the other.