System for the rapid change of clamping jaws on a machine tool

A quick clamping jaw change system for a machine tool, comprising:

• a blocking element having a first abutment face, and a first bearing face forming a first acute angle relative to a first reference plane disposed perpendicular to said first abutment face,
• a jaw mountable to said blocking element, said jaw comprising a second abutment face adapted to abut against said first abutment face, and a second bearing face adapted to bear against said first bearing face, said second bearing face angled correspondingly to said first bearing face, said jaw being movable in directions toward and away from said first abutment face and parallel to said first abutment face during insertion and removal of said jaw relative to the blocking element, said jaw including a reaction face forming a second acute angle relative to a second reference plane disposed parallel to said first reference plane, said second angle opening in the same direction as said first angle,
• a pusher mounted on said blocking element and including a pushing face angled correspondingly to said reaction face, said pusher being movable in a first direction relative to said blocking element toward said jaw such that said pushing face engages said reaction face and urges said second bearing face against said first bearing face to displace said jaw against said first abutment face,
• resisting means for resisting displacement of said pusher in a second direction opposite said first direction,
• said first angle being greater than said second angle so that said jaw can be moved away from said first abutment face only after said pusher has been disposed in said second direction.