Tool holder clamp assembly for cutting inserts and its pressing plate

A pressing plate suitable for positioning between a clamp and an upper surface of a cutting insert to facilitate clamping the cutting insert in a tool holder pocket, the pressing plate comprising:

• upper and lower surfaces;
• a front nose portion;
• a rear end portion comprising two spaced apart rear lobes;
• and
• a keyhole shaped groove extending between the upper and lower surfaces, the keyhole shaped groove having an enlarged inner cavity connected to a narrow neck which forms an opening in the rear end portion and separates the two rear lobes;
• wherein:
• a reinforcing protrusion is formed on the upper surface around the enlarged inner cavity, the reinforcing protrusion subtending a circumferential angle of at least 240° of the enlarged inner cavity relative to a center thereof.

A pressing plate suitable for positioning between a clamp and an upper surface of a cutting insert to facilitate clamping the cutting insert in a tool holder pocket, the pressing plate comprising:

• upper and lower surfaces;
• a front nose portion;
• a rear end portion comprising two spaced apart rear lobes;
• and
• a keyhole shaped groove extending between the upper and lower surfaces, the keyhole shaped groove having an enlarged inner cavity connected to a narrow neck which forms an opening in the rear end portion and separates the two rear lobes;
• wherein a pin receiving depression is formed near the rear end on the lower surface, the pin receiving depression extending on both sides of the narrow neck.

A pressing plate suitable for positioning between a clamp and an upper surface of a cutting insert to facilitate clamping the cutting insert in a tool holder pocket, the pressing plate comprising:

• upper and lower surfaces;
• a front nose portion;
• a rear end portion comprising two spaced apart rear lobes;
• and
• a keyhole shaped groove extending between the upper and lower surfaces, the keyhole shaped groove having an enlarged inner cavity connected to a narrow neck which forms an opening in the rear end portion and separates the two rear lobes;
• wherein:
• a reinforcing protrusion is formed on the upper surface around the enlarged inner cavity, the reinforcing protrusion subtending a circumferential angle of at least 240° of the enlarged inner cavity relative to a center thereof;
• the front nose portion has a curved surface slanted downwardly from the upper surface to the lower surface and the rear end portion comprises a vertical flat surface;
• and
• a pin receiving depression is formed near the rear end on the lower surface, the pin receiving depression extending on both sides of the narrow neck.