Title: Doorknob construction

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Abstract: A method of retaining Mortise Lock knobs and levers wherein a threaded male journal is provided on the knob or lever which co-acts with a female threaded nut whose outer diameter becomes a journal bearing surface permitting rotation of the knob or lever. A shoulder is provided at one end of the female threaded nut which becomes the retainer for the lock rose bushing. The shoulder end of the female threaded nut is perforated at its center line with an internal star-shaped hole which in turn accepts a standard square spindle which also co-acts with a square hole provided in the knob or lever.

The center of the star hole being concentric to the centerline of the bushing, the centerline of the square spindle and the centerline of rotation of the knob or lever. The female threaded nut provides continuous clearance adjustment while the interaction between the star-shaped hole, the square spindle and the square hole in the knob or lever provides secure rotation of the knob or handle within the rose bushing.