Control device for a pivoting valve flap for a heating and/or air conditioning installation in a motor vehicle

A flap valve comprising a valve flap mounted for pivoting movement between an open position and a closed position thereof, and a control device coupled to the flap for actuating the flap in displacement the open and closed positions, the control device comprising:

• a driving lever having a first end defining a pivot axis and a second end;
• a driven lever having a first end fixed to the valve flap and a second end;
• a link coupling the second end of the driving lever to the second end of the driven lever;
• and actuating means for rotating the driving lever through a course of angular displacement between an open position of the driving lever and a closed position of the driving lever, the valve flap being so oriented that the valve is open and closed when the driving lever is in the open and closed positions, respectively, of the driving lever, wherein the geometry of the control device is such that, when the driving lever is rotated from its open position towards its closed position, the valve flap reaches the closed position of the valve when the driving lever reaches an intermediate position just short of the closed position of the driving lever, whereby to define, between said intermediate and closed positions of the driving lever, a course of dead travel of the driving lever during which the valve is in its closed position, the link being adapted to bend under compression and being subjected to compression over the course of dead travel.