TRIGGER MECHANISM

摘要

A trigger mechanism for a ball activated device comprises a seat sleeve with seat defining members forming a fluid seal between the ball and the seat in an initial state and allowing the ball to pass through the seat in a final state. An alternating member can move radially in an aperture through an inner sleeve and abuts an outer surface on the seat sleeve in the initial state, is received in a recess on the seat sleeve in an intermediate state, and is received in a groove in the outer sleeve in the final state. A protective sleeve may extend axially from the seat sleeve over a seat receiving area. The mechanism is suitable for cementing and fracturing as particles cannot penetrate to its moving parts.

主权项

1. A trigger mechanism for a ball activated device, the trigger mechanism comprising:
an inner sleeve axially slidably disposed within an outer sleeve from an initial state wherein the ball activated device is inactive to a final state wherein the ball activated device is activated; a seat sleeve axially slidably disposed within the inner sleeve, the seat sleeve comprising radially moveable seat defining members configured to form a fluid tight seal with a ball in the initial state and allowing the ball to pass in the final state;
wherein the trigger mechanism is characterized in that an alternating member is disposed radially moveably in a radial aperture through a wall of the inner sleeve; wherein the alternating member abuts an upstream side of a first axial stopper on an inner surface of the outer sleeve and a radially exterior surface on the seat sleeve in the initial state, is received in a recess on the seat sleeve in an intermediate state, and is received in a groove in the inner surface in the final state.