Packer locking apparatus including a time delay apparatus for locking a packer against premature setting when entering a liner in a wellbore

A method of setting a packer in a liner of a wellbore, comprising the steps of:

• locking said packer in an unset condition prior to lowering said packer into said liner of said wellbore, the locking step includes the steps of biasing a lock block in a first direction and preventing a lock housing from moving, preventing a packer setting mandrel from moving when the lock housing is prevented from moving, and locking said packer in said unset condition when the packer setting mandrel is prevented from moving;
• releasing the lock on said packer and allowing said packer to change from said unset condition to a fully set condition when said packer is lowered into said liner of said wellbore;
• lapsing a period of time after the lock on said packer is released;
• and
• changing said packer from said unset condition to said fully set condition when said period of time has elapsed.

An apparatus for setting a packer in a liner of a wellbore after said packer is lowered into said liner, comprising:

• lock means for locking said packer in an unset condition prior to lowering said packer into said liner in said wellbore, said lock means releasing said lock on said packer when said packer is lowered into said liner in said wellbore, said lock means including lock block means biased initially in a first direction for biasing in a second direction opposite to said first direction when said packer is lowered into said liner of said wellbore, said lock on said packer being released when said lock block means is biased in said second direction;
• time delay means responsive to the release of said lock on said packer by said lock means for lapsing a period of time following the release of said lock on said packer and during the lowering of said packer into said liner;
• and
• condition changing means responsive to the lapsing of said period of time by said time delay means for changing said packer from said unset condition to a set condition when said period of time has elapsed.