Drill adapter for drill having central and lateral cutting inserts

A metal drill adapter having a central axis and comprising a cutting insert retaining portion connected to a drive stem, wherein the drive stem comprises a cylindrical outer surface in which are formed:

• a pair of elongated drive slots that extend along the central axis and communicate with a bottom surface of the drive stem;
• and
• a bearing surface between the pair of elongated drive slots;
• wherein the cutting insert retaining portion comprises identical first and second resilient clamping members which are rotationally 180° apart, the first and second resilient clamping members being separated by a slit which communicates with an internal through bore extending across a diameter of the cutting insert retaining portion.

A metal drill adapter in combination with a first cutting insert, wherein:

• (a) the drill adapter has a central axis and comprises a cutting insert retaining portion connected to a drive stem, wherein the cutting insert retaining portion comprises identical first and second resilient clamping members which are rotationally 180° apart, the first and second resilient clamping members being separated by a slit which communicates with an internal through bore extending across a diameter of the cutting insert retaining portion;
• (b) the first cutting insert is retained in the drill adapter's cutting insert retaining portion;
• and
• (c) the first cutting insert has at least one cutting edge provided with an associated rake surface and the drill adapter has a curved circumferential sidewall, the associated rake surface merging with the curved circumferential sidewall.

A metal drill assembly comprising:

• a drill shaft having a longitudinal axis and a cutting portion provided with an end bore that is coaxial with said longitudinal axis, the end bore having an inner wall provided with a plurality of elongated convex guides that extend along the longitudinal axis;
• and
• a drill adapter having a central axis and comprising a cutting insert retaining portion connected to a drive stem, wherein the drive stem comprises a cylindrical outer surface in which are formed:
• a pair of elongated drive slots that extend along the central axis and communicate with a bottom surface of the drive stem;
• and
• a bearing surface between the pair of elongated drive slots;
• wherein:
• the drive stem is positioned in the end bore with the elongated convex guides received into the elongated drive slots.

A metal drill assembly comprising:

• a drill shaft having a longitudinal axis and a cutting portion provided with an end bore that is coaxial with said longitudinal axis;
• a drill adapter having a central axis and comprising a cutting insert retaining portion connected to a drive stem, wherein:
• the drive stem is positioned in the end bore and secured therein;
• and
• the cutting insert retaining portion comprises identical first and second resilient clamping members which are rotationally 180° apart, the first and second resilient clamping members being separated by a slit which communicates with an internal through bore extending across a diameter of the cutting insert retaining portion.

A metal drill comprising:

• a drill shaft having a longitudinal axis and a cutting portion provided with an end bore that is coaxial with said longitudinal axis, the end bore having an inner wall provided with a plurality of elongated convex guides that extend along the longitudinal axis;
• a drill adapter having a central axis and comprising a cutting insert retaining portion connected to a drive stem, wherein the drive stem comprises a cylindrical outer surface in which are formed:
• a pair of elongated drive slots that extend along the central axis and communicate with a bottom surface of the drive stem;
• and
• a bearing surface between the pair of elongated drive slots;
• and
• a first cutting insert retained in said cutting insert retaining portion, wherein:
• the drive stem is positioned in the end bore with the elongated convex guides received into the elongated drive slots.

A metal drill comprising:

• a drill shaft having a longitudinal axis and a cutting portion provided with an end bore that is coaxial with said longitudinal axis;
• a drill adapter having a central axis and comprising a cutting insert retaining portion connected to a drive stem;
• and
• a first cutting insert retained in said cutting insert retaining portion;
• wherein:
• the drive stem is positioned in the end bore and secured therein;
• and
• the cutting insert retaining portion comprises identical first and second resilient clamping members which are rotationally 180° apart, the first and second resilient clamping members being separated by a narrow slit which communicates with an internal through bore extending across a diameter of the cutting insert retaining portion.

A metal drill having a longitudinal axis and comprising:

• a drill shaft having a cutting portion provided with an end bore that is coaxial with said longitudinal axis, the drill shaft further having first and second lateral cutting insert pockets formed on either side of the end bore;
• a drill adapter having a cutting insert retaining portion and a drive stem, said drive stem being removably retained in the end bore;
• a cutting insert of a first type screwlessly retained in the cutting insert retaining portion;
• and
• first and second indexable cutting inserts of a second type secured to respective first and second lateral cutting insert pockets and positioned on either side of said cutting insert of a first type.