Free fall stroker apparatus and method

A free fall stroker apparatus for raising and dropping a drop hammer attached to a cable, comprising:

• (a) a cable engaging means movable in at least three different directions, said cable engaging means engaging and raising the cable during motion in a first of said directions and releasing and dropping, wherein said first and second directions are non-reciprocal;
• (b) a track;
• (c) a track engaging means adapted to be movable within said track, said track engaging means being attached to said cable engaging means;
• and
• (d) means for propelling said track engaging means within said track to move said cable engaging means in said at least three directions.

A free fall stroker apparatus for raising and dropping a drop hammer attached to a cable, comprising:

• (a) a cable engaging sheave movable in a plurality of directions, said sheave engaging and raising said cable during motion in one direction and releasing and dropping said cable during motion in a second direction;
• (b) a track shaped as a parallelogram with a first leg extending in said first direction, a second leg extending in said second direction, a third leg parallel to said first leg and a fourth leg parallel to said second leg;
• (c) a track engaging means adapted to be movable within said track, said track engaging means being attached to said cable engaging means;
• (d) a hydraulic stroking cylinder with a telescoping arm for propelling said track engaging means within said track to move said cable engaging means in said plurality of directions;
• (e) a housing means for enclosing said free fall stroker, said cable extending through said housing from one side to the bottom thereof;
• (f) a pair of guide pulleys mounted within said housing for guiding said cable from the side to the bottom of said housing;
• (g) said track being positioned to align said sheave between said guide pulleys during said movement in said first direction and to remove said sheave from alignment between said guide pulleys during said movement in said second direction;
• wherein
• (h) said hydraulic cylinder is pivotally connected to said housing such that retracting said telescoping arm pulls said track engaging means in said first and second track legs in said first and second directions, respectively, and extending said telescoping arm pushes said track engaging means in said third and fourth legs in directions opposite to said first and second directions, respectively.

A method of raising and dropping a drop hammer attached to a cable, said method comprising the steps of:

• (a) running the cable between a pair of guide means;
• (b) moving a cable engaging means in one direction between the guide means to engage the cable and raise the hammer;
• and
• (c) moving the cable engaging means in a second direction which is non-reciprocal to said first direction to release the cable and thereby drop the hammer.

A free fall stroker apparatus for raising and dropping a cable, comprising:

• (a) a cable engaging means movable in a plurality of directions, said cable engaging means engaging and raising the cable during motion in a first direction and releasing and dropping said cable during motion in a second direction;
• (a) a track shaped as a parallelogram with a first leg extending in said first direction, a second leg extending in said second direction, a third leg parallel to said first leg and a fourth leg parallel to said second leg;
• (b) a track engaging means adapted to be movable within said track, said track engaging means being attached to said cable engaging means;
• and
• (c) means for propelling said track engaging means within said track to move said cable engaging means in said plurality of directions.

A free fall stroker apparatus for raising and dropping a drop hammer attached to a cable, comprising:

• (a) a cable engaging means movable in a plurality of directions, said cable engaging means engaging and raising the cable during motion in a first direction and releasing and dropping said cable during motion in a second direction;
• (b) a track shaped as a parallelogram with a first leg extending in said first direction, a second leg extending in said second direction, a third leg parallel to said first leg and a fourth leg parallel to said second leg;
• (c) a track engaging means adapted to be movable within said track, said track engaging means being attached to said cable engaging means;
• and
• (d) means for propelling said track engaging means within said track to move said cable engaging means in said plurality of directions.

A method of raising and dropping a drop hammer attached to a cable, said method comprising the steps of:

• (a) running the cable between a pair of guide means;
• (b) moving a cable engaging means via a parallelogram shaped track along a first track leg extending in a first direction between the guide means to engage the cable and raise the hammer;
• (c) moving the cable engaging means along a second track leg in a second direction to release the cable and thereby drop the hammer;
• and
• (d) moving said cable engaging means along a third leg in a direction opposite to said first direction, and then along a fourth leg in a fourth direction opposite to said second direction to a point of origin.