Impact damper

1. Field of the Invention An impact damper as a connecting member between a bumper and a chassis of a motor vehicle for the purpose of damping the shock loading during a collision between this motor vehicle and an obstacle through hydraulic damping forces and gas-spring forces. This impact damper includes an inner tube which can be displaced telescopically inside an outer tube, thereby changing the volume of a pressurized gas space, which interact by means of a separating piston with a first liquid space, which communicates hydraulically via a restriction orifice with a second liquid space, which is bounded by a deformation element. The separating piston is arranged in a floating manner in the inner tube and thereby brings about a static equilibrium by pressure compensation in the liquid spaces and in the gas space. The outer tube furthermore has a drawn-in portion around the deformation element, which brings the outer tube to a reduced diameter, within which is arranged a compensation space that can be filled with gas formed by an end wall at the end of the outer tube. The deformation element has an adjustable control valve, which can be controlled from outside the impact damper by a detection sensor system. The compensation space furthermore communicates with an accumulator, which can likewise activate the pressure in the gas spaces in response to the detection sensor system.