초록 ▼

An outer tubular body member has a plurality of circumferentially spaced outwardly bowed spring fingers on its inner surface projecting downwardly to near the lower end of the body member and normally spaced apart. An inner tubular member is longitudinally movable in the body member and has a ring p

An outer tubular body member has a plurality of circumferentially spaced outwardly bowed spring fingers on its inner surface projecting downwardly to near the lower end of the body member and normally spaced apart. An inner tubular member is longitudinally movable in the body member and has a ring portion at its lower end surrounding the upper portions of the spring fingers and movable downwardly to cam the fingers inwardly to grasp a loose article in the well. Latching tongues on the spring fingers engage the ring when the fingers are cammed inwardly. In one form the body member is attachable to a drill string and the upper end of the inner member functions as a piston to be pushed downwardly by drilling mud from the drill string. In another form the inner member can be attached to the drill string and held in an upper position relative to the body member by shear pins which are severable by the weight of the drill string.

대표청구항 ▼

A retriever for loose articles in wells, comprising: a generally tubular body member adapted to be lowered into a well; a plurality of circumferentially spaced downwardly extending resilient fingers fixed at their upper ends to a lower portion of said body member, said resilient fingers being normal

A retriever for loose articles in wells, comprising: a generally tubular body member adapted to be lowered into a well; a plurality of circumferentially spaced downwardly extending resilient fingers fixed at their upper ends to a lower portion of said body member, said resilient fingers being normally spaced apart to receive a loose article therebetween and each having an inturned lower end defining a hook portion, said fingers being configured to define downwardly and outwardly sloping cam surfaces along at least the upper portions thereof; a ring member surrounding the upper portions of said fingers and being movable downwardly along said cam surfaces to thereby flex said fingers inwardly to move said hook portions toward each other and thereby grasp a loose article in said well; actuator means for moving said ring member downwardly relative to said tubular body member; and interengageable latching means on said ring and on said fingers adjacent the lower ends of said cam surfaces to latch said ring against upward movement relative to said fingers after said ring has been moved downwardly over said cam surfaces and thereby prevent release of a loose article held by said hook portions and comprising protuberances on said fingErs, each having a downwardly facing surface engageable with an upwardly facing surface of said ring member.