Hole saw

A hole saw including in combination a shank having a drive collar at the front end of a drive shaft, a hole saw body having a base perpendicular to the axis thereof, and mounting means for removably attaching the base of the hole saw body to the drive collar of the shank, said hole saw comprising:

• a. said drive collar of the shank being formed substantially integrally with the drive shaft;
• b. a cylindrical boss projecting from the front side of said drive collar and having a diameter smaller than said drive collar and coaxial with the shank, said drive collar having a bolt receiving through-hole bored therein at a position radially spaced from said boss which is parallel to the axis of the shank;
• c. a bolt received in said bolt receiving through-hole, said bolt having a length such that a threaded portion of the bolt projects beyond the front side of the drive collar when the bolt is inserted into the bolt receiving through-hole until its head engages the rear side of the drive collar;
• d. the base of said hole saw body having a center hole bored centrally therein for receiving the boss projecting from the front side of said drive collar, said base further having at least one threaded hole bored therein at a position radially spaced from said center hole for receiving the threaded portion of the bolt extending through said bolt receiving through-hole;
• e. whereby, when said center hole in the base of the hole saw body is engaged by said boss projecting from the front side of the drive collar and when the threaded portion of the bolt received in the bolt receiving through-hole of the drive collar is brought in thread engagement with said threaded hole in the base of the hole saw body, said base of the hole saw body goes in close contact with the front side of the drive collar so that the hole saw body can be firmly retained in position by the drive collar.