Abstract: A camshaft adjuster mounted between a taut strand and a slack strand of a chain connecting an intake camshaft to an exhaust camshaft has two tensioning shoes which are urged by a spring away from each other and against the inner sides of the chain strands. One tensioning shoe is mounted on a reciprocable piston within which a plunger carrying the other tensioning shoe is slidable against the force of the spring. The piston is moved against the taut strand by pressurization of a pressure chamber through a nonreturn valve and the plunger is moved with the piston so that the taut and slack strands are moved together and compression of the tensioning spring is thereby maintained relatively constant. A damping chamber may be provided with throttling bores in the piston and/or plunger to control the damping effect.