Patent ID: 6196309
Filing Date: 2001-03-06
Classification: E21B

Abstract:
A device for retrieving an object from a well bore comprising:a tubular housing having an outer portion and inner portion;a skirt attached to said tubular housing, said skirt having an inner bore and wherein said skirt contains a first window and a second window, said first window having a first shoulder thereon and said second window having a second shoulder thereon;a core being disposed within said inner bore of said skirt, said core being connected to said skirt with a shear pin and wherein said core has a first end and a second end, and wherein said second end contains an angled shoulder;a dog member disposed about said core, said dog member having a first end that cooperates with said first shoulder of said first window and a second end that cooperates with said second shoulder of said second window wherein said dog member contains an angled leg that is configured to cooperate with said angled shoulder of said core;a core nut attached to said first end of said core, said core nut cooperating with said inner portion of said tubular housing to form a first spring chamber;a first spring disposed within said first spring chamber, said first spring biasing a first end of said core nut in an upward direction so that as said shear pin is sheared, said core is slidably received within said inner portion of said tubular housing.