A punching machine comprising at least one punching head including a support
body
having a first end delimiting a peripheral shoulder, a second end, and at least
two parallel seats being angularly spaced from one another and extending through
said support body from said first end to said second end; a punching tool holder
slibably mounted in at least one of said seats; a multiplicity of removable resilient
means angularly spaced from one another, each having a first end resting on said
peripheral shoulder and a second end facing away from said peripheral shoulder;
an annular cap member arranged in front and spaced from said peripheral shoulder
and designed to abut against said second end of said resilient means; a rotor member
mounted for rotation on said annular cap member and having an inner face thereof
facing towards said punching tool holder; a sliding member projecting from said
inner face and arranged to slide onto said punching tool holder when said rotor
member rotates; and driving means designed to stepwise drive said rotor member,
whereby locating said sliding member onto a pre-selected punching tool holder.