Inflatable packer assembly with control valve

A control valve assembly for a downhole tool, said downhole tool being constructed for connection to a tubular member to be lowered into a well hole;

• comprising:
• a mandrel;
• a valve body, connected to said mandrel, said valve body including:
• an inlet means for communicating with an interior of said tubular member;
• an outlet means, for directing fluid to a component of said downhole tool which is to be actuated by said fluid;
• a first bore means, disposed in said valve body, for communicating said inlet with an annular space between said tubular member and said well hole;
• a second bore means, disposed in said valve body, for communicating with said annular space;
• a first port means, connecting said first and second bore means;
• and
• a second port means, connecting said second bore means and said outlet;
• a first piston disposed in said first bore means, said first piston having first and second ends arranged for fluid communication with said inlet and said annular space, respectively, said first piston being movable between a first position blocking said first port means and a second position allowing fluid communication between said inlet and said first port means;
• means for holding said first piston in said first position until a fluid pressure differential between said interior of said tubular member and said annular space reaches a first predetermined level, and for releasing said first piston so that it may be moved to said second position by said pressure differential when said differential reaches said first level;
• a second piston disposed in said second bore means, said second piston having first and second ends arranged for fluid communication with said first port means and said annular space, respectively, said second piston being movable between a first position allowing fluid communication between said first and second port means and a second position blocking said second port means;
• and
• means for holding said second piston in its said first position until said fluid pressure differential reaches a second predetermined level, said second level being higher than said first level, and for releasing said second piston so that it may be moved to its second position by said pressure differential when said differential reaches said second level.