Patent ID: 7267538

Claim:
An adjustable knockout for use in injection molding machines, comprising; a first hollow cylindrical bar having a first end, a second end, and a plurality of holes and notches at uniform intervals for securely fixing the knockout, said first bar's second end having a first internal screw thread, wherein said first bar's second end's first internal screw thread's diameter tapers in width from larger to smaller towards the center of said first bar so as to threadedly secure the knockout to a stationary portion of an injection molding machine of different sizes; an adjustment screw with uniform miming screw thread having a first end and a second end, wherein said adjustment screw's first end is rigidly fixed inside said first hollow cylindrical bar up to a distance that allows said adjustment screw's second end to be substantially aligned a with said first bar's second end's edge; and a second hollow cylindrical bar having a first end and a second end, a second internal screw thread cut along said second bar's first end, and a third uniform internal screw thread extending from the second bar's second end towards the center of said second bar, wherein said second internal screw thread tapers in width from larger to smaller for threadedly securing the knockout to a stationary portion of an injection molding machine of different sizes; wherein the adjustment screw diameter is smaller than the diameter of the second cylindrical bar's second internal screw thread, and said second cylindrical bar's external diameter is smaller than said first cylindrical bar's second end's internal diameter so as to allow said second bar to be threadedly adjusted to said adjustment screw to vary the length of the knockout and then be locked in place; and said second bar having a plurality of marks so as to indicate the length that the knockout is being adjusted to.