Patent ID: 7900708

Claim:
A downhole anchor assembly for a tubing string, comprising: a mandrel to be coupled to the tubing string, the mandrel comprising a shoulder along a groove on the mandrel; an anchor block comprising a structure received in the groove, to be pushed by the shoulder with rotation of the mandrel for moving the anchor block from a run position out of contact with a well bore to a set position in contact with the well bore to set the downhole anchor assembly in the well bore, the anchor block further comprising extensions; a drag block, coupled to the mandrel, the drag block comprising shoulders forming grooves that receive the extensions of the anchor block to slidably couple the anchor block and the drag block together; and a biasing arrangement to bias the anchor block away from the well bore and the drag block toward the well bore, the drag block extending beyond the anchor block in a direction along the drag block grooves toward the well bore and contacting the well bore when the anchor block is in the run position, the rotation of the mandrel to push the structure for moving the anchor block from the run position to the set position sliding the anchor block relative to the drag block to extend the anchor block beyond the drag block and into contact with the well bore.