Clamping apparatus for positioning and fixing work pieces

A clamping apparatus for positioning work pieces to be machined on a work table of a machine tool, comprising at least one clamping rail member adapted to be attached to said work table of said machine tool, and at least one work piece holder adapted to be clamped to said clamping rail member in a precise position, characterized in that:

• each of said at least one clamping rail member is provided with an elongate protruding portion, said protruding portion delimiting between a bottom side of said protruding portion and the surface of said work table an elongate recess and including a clamping element extending into said elongate recess wherein said protruding portion further includes a plurality of apertures substantially perpendicular to said bottom side with said clamping element being placed into any of the said plurality of apertures;
• and
• each of said at least one work piece holder includes at least one protruding clamping portion configured to insert into said elongate recess and to be clampingly fixed by said clamping element;
• wherein said clamping element is configured to press upon a corresponding protruding clamping portion of said at least one work piece holder towards the work table;
• at least one clamping rail member is provided with a flat bottom surface adapted to rest on said work table of said machine tool and defining a Z-direction reference, and said elongate protruding portion of said clamping rail member includes a front surface running perpendicular to said flat bottom surface;
• at least one of said at least one work piece holder is provided with a reference surface located on a side of said holder on which said clamping portion is provided with said protruding portion extending from a portion of said side surface, said reference surface being adapted to rest against said front surface of said at least one clamping rail member;
• and
• said clamping portion of said at least one work piece holder is provided with an inclined clamping surface located at a top side thereof, said clamping element provided on said elongate protruding portion of said at least one clamping rail member engaging said inclined clamping surface such that said work piece holder is pulled towards said clamping rail member to rest with said reference surface against the front surface of the clamping rail member upon clamping said work piece holder in said clamping rail member.