Anchoring mechanism for a well tool

Claim 2

An anchor assembly for use in anchoring a well tool in a well bore, comprising: a slip member having a head portion joined by a wall section to a dog portion; housing means having a recess for receiving said wall section and said dog portion and including means for coupling said slip member against longitudinal relative movement, said slip member being free to move laterally inwardly and outwardly within limits and to tilt in either direction within said recess; and spring means engaged between said wall section and a surrounding portion of said housing means for continuously urging said slip member laterally inwardly, said spring means being capable of deflection to a substantially flat condition upon outward movement of said slip member.

Claim 3

The anchor assembly of claim 1 wherein said spring means is in the form of a conical coil.

Claim 4

The anchor assembly of claim 2 wherein said wall section is formed to the rear of said head portion and said dog portion so as to define a pocket for receiving the large end of said conical coil.

Claim 5

The anchor assembly of claim 3 wherein said surrounding portion is provided by a band that is fixed to said housing member, said band having a lesser vertical dimension than said recess to provide an opening to the side of said housing member, said dog portion being loosely received in said opening.

Claim 6

An anchor assembly for use in anchoring a well tool in a well bore, comprising: annular member having a recess in one end; a slip element having a head portion with outer toothed surfaces and joined by a wall section to a dog portion, said wall section and dog portion being coupled within said recess and adapted for tilting as well as lateral inward and outward movement; and spring means engaging between said wall section and a surrounding portion of said annular member for continuously urging said slip element to move laterally inwardly, said spring means being constructed and arranged to assume upon deflection a substantially flat condition, said head portion when engaged by an expander tilting first about said dog portion until a slip tooth engages a well casing wall and then said dog portion tilting about said head portion until all of said toothed surfaces are engaging the casing wall, said spring means deflecting to a substantially flat condition upon complete outward movement of said slip element.

Claim 7

An anchor assembly for use in anchoring a well tool in a well bore, comprising: annular member having a recess in one end; a slip element having a head portion with outer toothed surfaces and joined by a wall section to a dog portion, said wall section and dog portion being coupled within said recess and adapted for tilting as well as lateral inward and outward movement; and spring means engaging between said wall section and a surrounding portion of said annular member for continuously urging said slip element to move laterally inwardly, said spring means being constructed and arranged to assume upon deflection a substantially flat condition, said head portion when engaged by an expander tilting first about said dog portion until a slip tooth engages a well casing wall and then said dog portion tilting about said head portion until all of said toothed surfaces are engaging the casing wall, said spring means deflecting to a substantially flat condition upon complete outward movement of said slip element.

Claim 8

The anchor assembly of claim 5 wherein said spring means is a conical coil compression spring having the coil formed on a helix of diminishing diameter so as to provide a spiral coil when completely flat.

Claim 9

The anchor assembly of claim 6 wherein said wall section is formed rearwardly of the outer surfaces of said head portion and said dog portion to provide a pocket that receives the large end of said spring.

Claim 10

The anchor assembly of claim 7 wherein said annular member includes a coupling band overlying said wall section and having a lesser vertical dimension than said recess so that said recess opens to the side of said annular member, said dog portion being loosely received in said opening.

Claim 11

An anchor assembly for use in anchoring a well tool in a weLl bore, comprising: a housing member having a plurality of circumferentially spaced recesses opening at one end thereof; a plurality of circumferentially spaced slip elements, each slip element adapted to be coupled in a respective one of said recesses, each slip element having a head portion with inner inclined surfaces and outer toothed surfaces and joined by a rearwardly disposed intermediate wall section to an outwardly projecting dog portion, the wall section and dog portion being coupled within a respective recess and adapted for lateral inward and outward movement therein, each recess opening to the side of said housing member at a location spaced from the end surface thereof, the dog portion of each slip element being loosely fitted within a respective opening; means between said openings and said end surface overlying the wall section of each slip element; and a conical coil spring received in each recess and bearing between the wall section of each slip element and said overlying means so as to continuously urge a respective slip element laterally inwardly, each coil spring being arranged and adapted to assume a substantially flat condition upon outward shifting of the slip elements by an associated expander.

Claim 12

An anchor assembly for use in anchoring a well tool in a weLl bore, comprising: a housing member having a plurality of circumferentially spaced recesses opening at one end thereof; a plurality of circumferentially spaced slip elements, each slip element adapted to be coupled in a respective one of said recesses, each slip element having a head portion with inner inclined surfaces and outer toothed surfaces and joined by a rearwardly disposed intermediate wall section to an outwardly projecting dog portion, the wall section and dog portion being coupled within a respective recess and adapted for lateral inward and outward movement therein, each recess opening to the side of said housing member at a location spaced from the end surface thereof, the dog portion of each slip element being loosely fitted within a respective opening; means between said openings and said end surface overlying the wall section of each slip element; and a conical coil spring received in each recess and bearing between the wall section of each slip element and said overlying means so as to continuously urge a respective slip element laterally inwardly, each coil spring being arranged and adapted to assume a substantially flat condition upon outward shifting of the slip elements by an associated expander.