Patent ID: 7438139
Filing Date: 2008-10-21
Classification: B23B,B25D,Y10T

Abstract:
1. A tool assembly, comprising: a housing defining a chamber; a reciprocating work tool arranged in the chamber; a tool retention member having an aperture through which the work tool extends; engaging structure including mutually engaging protrusions on the housing and the tool retention member configured to permit engagement of the tool retention member with the housing by relative rotation of the tool retention member and the housing; retention structure on the work tool configured to prevent removal of the work tool from the housing when the tool retention member is engaged with the housing; one or more locking screws configured to lock the tool retention member and housing against relative rotation; and a prestressing structure located between the protrusions on the housing and a portion of the tool retention member and configured to urge the tool retention member away from the housing.