Electrically controlled release device

A device for releasably connecting a wireline to a downhole tool, the device comprising:

• a housing;
• a latch mounted at one end of the housing, the latch having a central opening and a plurality of projecting members extending into the housing;
• an actuator having a first end disposed in the central opening;
• and
• a shape memory alloy member positioned in parallel with the load path of the actuator and functionally connected to the actuator in a manner such that the actuator is held in a first position prior to activation of the shape memory alloy member and the actuator is moveable to a second position after the shape memory alloy member is activated;
• wherein the projecting members have inner surfaces for engagement of an outer surface of the actuator, the inner surfaces of the projecting members and the outer surface of the actuator being parallel to one another and the longitudinal axis of the actuator;
• and
• wherein the latch is held in connection with the housing by an interference fit between the projecting members and the housing when the actuator is in the first position, and wherein the latch is disengaged from the housing when the actuator is in the second position.

A device for releasably connecting a conveyance to a downhole tool, the device comprising:

• a housing;
• a latch mounted at one end of the housing, the latch having a central opening and a plurality of projecting members extending into the housing;
• an actuator having a first end disposed in the central opening;
• and
• a releasable connector functionally connected to the actuator in a manner such that the actuator is held in a first position prior to activation of the releasable connector and the actuator is moveable to a second position after the releasable connector is activated;
• wherein the projecting members have inner surfaces for engagement of an outer surface of the actuator, the inner surfaces of the projecting members and the outer surface of the actuator being parallel to one another and the longitudinal axis of the actuator;
• and
• wherein the latch is held in connection with the housing by an interference fit between the projecting members and the housing when the actuator is in the first position, and wherein the latch is disengaged from the housing when the actuator is in the second position.