Graco Inc.

Calvin S Hulburt

Thomas J Schaefer

The reciprocating pump shaft is joined to a reciprocating motor shaft by the coupling of this invention. The pump shaft is provided with a knob-like end having a chamfered angle between the knob and a reduced diameter section adjacent the knob. A two piece annular collar that's about the chamfered shoulder and the reduced diameter section and the collar is provided with a chamfered shoulder having a slight angular mis-match with the shaft shoulder. A nut draws the pump shaft upwardly against the end of the motor shaft and is tightened to the point where the pre-load between the two shafts is greater than the alternating load imposed by the motor.

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Minneapolis, MN, United States of America

Calvin S Hulburt