Fluid brake device and variable valve timing apparatus

摘要

A fluid brake device has a case defining a fluid chamber. Magneto-rheological fluid is contained in the fluid chamber. A brake member is rotatably supported on the case and receives a braking torque according to the viscosity of the magneto-rheological fluid. The device has a movable member driven by a thermo-sensitive wax so that a volume of the fluid chamber is increased as the temperature in the fluid chamber is increased. The movable member is driven to maintain a pressure in the fluid chamber within an allowable range when the temperature in the fluid chamber is changed.