Well tool and releasing device therefor

Claim 2

Improved releasing means for well tool gripping members wherein said gripping members are pivotal on well tools between retracted and well bore wall engaging positions, the improvement comprising: a sleeve carried by the well tool and extending through and moveable relative to said gripping member; and, cam means moveably attached to said well tool and slideably located between said gripping member and the well bore wall, said cam means adapted to be engaged by movement of said sleeve and slideably wedged between said gripping member and the well bore wall, said cam means thereby disengaging said gripping member from said wall.

Claim 3

The releasing means of claim 1 wherein said cam means includes: an elongated cam member; means connecting said cam member to said sleeve; and, biasing means engaging said cam member and sleeve resiliently urging said cam member toward said gripping member.

Claim 4

The releasing means of claim 2 wherein the gripping member includes a slot extending along one surface thereof adjacent the well bore wall, wherein said biasing means urges said cam member into said slot.

Claim 5

The releasing means of claim 3 wherein said sleeve includes a lug portion that projects through an opening in the gripping member located at one end of the slot, and wherein said biasing means and pivot means are mounted on said lug portion.

Claim 6

The releasing means of claim 4 wherein said cam member has a thickness greater than the depth of at least a portion of the slot in the gripping member whereby said cam member simultaneously engages both the well bore wall and gripping member to move the gripping member out of engagement with the well bore wall upon movement of said sleeve and cam member relative to the gripping member and relatively toward the engagement between the gripping member and well bore wall.

Claim 7

The releasing means of claim 1 wherein the gripping member has a slot extending along one surface thereof adjacent the well bore wall and wherein said cam means includes: a cam member slidingly located in said slot, said cam member being engageable with said sleeve; biasing means engaging said cam member and the gripping member for urging said cam member relatively away from the well bore wall; and, retaining means for holding said cam member in the slot.

Claim 8

In an improved well tool including a gripping member located for pivotal movement on said tool and having gripping portions engageable with the wall of the well bore when pivoted to hold said tool in a relatively fixed position in the well bore, said tool also including means for causing pivoting of said gripping member toward the wall engaging position, the improvement comprising: a sleeve moveably carried by the well tool and extending through said gripping member and moveable relative to said gripping member; said gripping member having a slot in the exterior thereof extending at least partially through one of said gripping portions; and, cam means moveably attached to said well tool and at least partially disposed in said slot, and slideable therein, said cam means having a portion simultanEously engageable with said gripping member and well bore wall arranged, upon movement of said sleeve and cam means in one direction for forcing said gripping portions out of engagement with the well bore wall.

Claim 9

In an improved well tool including a gripping member located for pivotal movement on said tool and having gripping portions engageable with the wall of the well bore when pivoted to hold said tool in a relatively fixed position in the well bore, said tool also including means for causing pivoting of said gripping member toward the wall engaging position, the improvement comprising: a sleeve moveably carried by the well tool and extending through said gripping member and moveable relative to said gripping member; said gripping member having a slot in the exterior thereof extending at least partially through one of said gripping portions; and, cam means moveably attached to said well tool and at least partially disposed in said slot, and slideable therein, said cam means having a portion simultanEously engageable with said gripping member and well bore wall arranged, upon movement of said sleeve and cam means in one direction for forcing said gripping portions out of engagement with the well bore wall.

Claim 10

The improved well tool of claim 7 wherein said cam means includes: a cam member; means supporting saidcam member on said sleeve; and, biasing means urging said cam member toward the gripping member.

Claim 11

The improved well tool of claim 6 wherein said cam means includes: a cam member slidingly positioned in said slot; biasing means engaging said cam member and gripping member for urging said cam member relatively away from the well bore wall; and, retaining means for holding said cam member in said slot.

Claim 12

The improved well tool of claim 8 and also including a lug portion on said sleeve extending through an opening in the gripping member located at one end of the slot, said lug portion carrying said cam member, pivot means, and biasing means.

Claim 13

An improved tool for use in a well bore comprising: an elongated mandrel; a sleeve encircling said mandrel and slideable thereon; a unitary gripping member encircling said sleeve and pivotal thereon between a retracted position and a wall engaging position; abutment means moveable on said mandrel and engageable with said gripping member to pivot said gripping member into said wall engaging position; and, cam means moveably attached to said tool and actuated by movement of said sleeve for simultaneously engaging said gripping member and well bore wall to pivot said gripping member out of engagement with the well bore wall.

Claim 14

An improved tool for use in a well bore comprising: an elongated mandrel; a sleeve encircling said mandrel and slideable thereon; a unitary gripping member encircling said sleeve and pivotal thereon between a retracted position and a wall engaging position; abutment means moveable on said mandrel and engageable with said gripping member to pivot said gripping member into said wall engaging position; and, cam means moveably attached to said tool and actuated by movement of said sleeve for simultaneously engaging said gripping member and well bore wall to pivot said gripping member out of engagement with the well bore wall.

Claim 15

The improved well tool of claim 11 wherein said cam means includes: a cam member; means supporting said cam member on said sleeve; and, biasing means resiliently urging said cam member toward said gripping member and relatively away from the well bore wall.

Claim 16

The improved well tool of claim 11 wherein said cam means includes: a cam member slidingly located in the slot; biasing means engaging said cam member and gripping member for urging said cam member relatively away from the well bore wall; and, retaining means for holding said cam member in said gripping member.

Claim 17

The improved well tool of claim 11 wherein: said gripping member has a slot formed in one surface that is adjacent the well bore wall and an opening extending therethrough at one end of said slot; and, said sleeve includes a lug portion extending through said opening, said lug portion carrying said cam means.

Claim 18

The improved well tool of claim 14 wherein said cam member projects from said lug portion into said slot and has a thickness greater than the depth of at least a portion of said slot whereby movement of said sleeve moves said cam member along said slot into simultaneous engagement with said gripping member and well bore wall when said gripping member is in the wall engaging position to move said gripping member into the retracted position.