Hole saw adaptor

A hole saw adapter comprising an adapter body with a first end equipped with a spindle for fastening to a drive unit, and a second end receiving a hole saw and a central drill, in which

• the adapter body is extended and equipped with a longitudinally running axial slit,
• the central drill is releasably fastened to an inner axially displaceable holder, said inner axially displaceable holder is displaceable in the longitudinally running axial slit in the adapter body and is connected to an external displacer,
• said external displacer is a ring or a casing being displaceable longitudinally along the axial slit and which surrounds the adapter body, providing forced axial displacement of the axially displaceable holder and the central drill in the longitudinally running axial slit to push out a core remaining in the hole saw after drilling, wherein
• the longitudinally running axial slit is a cross-wise through-running open slit in the adapter body receiving a tool that can be completely pushed through the adapter body, and
• the displacer comprises a partial cover lying externally to the longitudinally running slit providing a support face for said tool giving forced displacement of the displacer along the longitudinally running slit.