Device with adjustable rigidity for absorbing impact energy and method for adjusting such a device

The device has the housing (105) with a disengagable die (130) to receive and deform a deformation element (120) based on the movement of the deformation element in feed direction (155) by impact energy. A support unit (135) is arranged to support the die in first position for moving in direction transverse to feed direction by radial force of deformation element and to support in a second position for disengaging. A pressure chamber is arranged in the housing at the upstream of support unit to adjust the pressure wave generated by pressure generating device. An independent claim is included for method for adjusting rigidity of the device for receiving impact energy.