Mechanical grapple for grabbing and holding sacks and bags

A device mountable on a transport mechanism for contacting, grasping and holding an object having a deformable surface, comprising:

• a mounting bracket mountable to said transport mechanism;
• a first and a second holding brackets, movable relative to each other and held by said mounting bracket wherein said first holding bracket is fixedly attached to said mounting bracket and said second holding bracket is pivotably attached to said mounting bracket and moves relative to said first holding bracket;
• a first roller, rotatable about a first roller axis and rotatably supported on said first holding bracket, said first roller further including a dragging surface for engaging and drawing said deformable surface when contacting said deformable surface of said object;
• a second roller, rotatable about a second roller axis and rotatably supported on said second holding bracket, said second roller further including a dragging surface for engaging and drawing said deformable surface when contacting said deformable surface of said object;
• and
• a drive means for rotating at least one of the said rollers;
• wherein when said first roller turns along a first direction, and said roller surface of said first roller is placed into contact with said deformable surface of said object, said first roller surface draws said deformable surface of said object into an inter-roller region between said first and second rollers, thereby grasping said object.

A method of manipulating an object;

• mounting a grapple device to a transport mechanism, wherein said grapple device comprises (i) a supporting bracket assembly (ii) a first roller, having a roller axis, said roller rotatably mounted on said supporting bracket assembly, and said first roller being rotatable about its axis, wherein said first roller further comprises a gripping surface for engaging the graspable portion of the object, (iii) a second roller, having a roller axis, and said second roller being rotatable about its axis, wherein said second roller further comprises a gripping surface for engaging the graspable portion of said object, (iv) a biasing means to bias said rollers toward each other with sufficient force to facilitate holding said graspable portion of said object in place between said rollers, (v) a driving means for rotating said rollers, and (vi) a holding means selectively operable to releaseably engage at least one of said rollers, and prevent rotation of said roller when engaged;
• positioning said grapple device close to said object;
• activating a grabbing operation of said grapple device, wherein said driving means rotates said first roller in a first direction, such that said first roller and said second roller rotate in opposite directions inwardly, and when said roller surface of said first roller contacts said object, a graspable portion of said object is drawn between said first and the second rollers, thereby grasping said object;
• stopping the rotation of said rollers by said holding means when a sufficient portion of said object is grabbed between said rollers, thereby holding said object;
• maneuvering said grapple device and object, via said transport mechanism, to a desired location;
• and
• releasing said object from said grapple wherein said driving means rotates said first roller in a second direction, said first roller and said second roller turn outwardly in opposing rotations.