Patent ID: 6681492
Filing Date: 2004-01-27
Classification: A01G

Abstract:
A tree pruner comprising:first handle; a second handle comprised of, at a top end, a push edge and a second confining slot; a fixed jaw plate comprised of two pieces identical in shape and thickness and arranged at an interval on a top end of said first handle whereby said fixed jaw plate has a top jaw portion which is comprised of a serrated edge; a movable jaw plate fastened pivotally to said fixed jaw plate by a first pivot such that a cutting edge of said movable jaw plate is corresponding in location to said serrated edge of said fixed jaw plate, said movable jaw plate being provided at an arcuate bottom end with a tooth edge, said movable jaw plate further comprising a recovery spring which is fastened between said movable jaw plate and said fixed jaw plate; a gear mounted rotatably on a second pivot which is pivoted to the top end of said second handle whereby said gear is engaged with said toothed edge of said movable jaw plate; a check plate fastened pivotally to said fixed jaw plate by a third pivot and provided at a movable end with a projection which is slidably received in a first confining slot of said fixed jaw plate for confining the swiveling of said check plate such that said projection is pushed by said push edge of the top end of said second handle so as to cause said check plate to swivel, said check plate further comprising a counterclockwise stop edge, a clockwise guide edge, and a torsion spring urging at one end thereof said check plate to enable the movable end of said check plate to engage said gear, thereby enabling said gear to turn clockwise to pass said clockwise guide edge and causing said gear to be arrested by said counterclockwise stop edge and a push plate pivoted with said second handle by a fourth pivot and provided at a movable end thereof with a pillar which is slidably received in said second confining slot of the top end of said second handle so as to confine the swiveling of said push plate, said push plate further comprising a torsion spring, fastened thereto such that one end of said torsion spring urges said push plate to enable the movable end of the push plate to engage said gear; wherein said second handle being swivelled away from said first handle so as to cause said movable jaw plate to move away from said fixed jaw plate, thereby resulting in an open space to accommodate a tree twig between said movable jaw plate and said fixed jaw plate whereby said push edge of the top end of said second handle pushes said projection of said check plate to cause said check plate to swivel to disengage said gear, with said movable end of said push plate moving along an arcuate-guide edge of a bottom end of said fixed jaw plate to become disengaged with said gear, thereby causing said movable jaw plate to be forced by said recovery spring of said movable jaw plate to move away from said fixed jaw plate; wherein a first incision is made into the tree twig by the cutting edge of said movable jaw plate in conjunction with said serrated edge of top jaw portion of said fixed jaw plate at the time when said second handle is swivelled toward said first handle so as to cause said check plate and said push plate to engage said gear such that said gear is pushed by said push plate to turn clockwise on said second pivot, and that said gear in motion actuates said movable, jaw plate to turn counterclockwise on said first pivot to swivel toward said fixed jaw plate; and wherein said second handle being swivelled again in the direction away from said first handle in the event that the first incision fails to sever the tree twig, with said movable jaw plate remaining stationary by virtue of the fact that said gear is not pushed by said push plate to turn, and that said gear is arrested by said counterclockwise stop edge of said check plate.