Variable force tool
AssigneeFiskars Consumer Oy Ab
InventorErkki Olavi Linden
Life of this patent
Estimating the term…
Abstract
A variable force lopping tool is provided with a gear mechanism configured so that maximum leverage is obtained at a point in the cutting stroke corresponding to the maximum resistance by the workpiece being cut. The mechanism comprises a pair of mating gears formed on first and second elongated members and cooperating with a plate having a forwardly extending jaw or blade. The plate is pivotally connected to the first member. The second member is pivotally connected to a rearwardly extending tang of the plate.
Claims20
A variable force lopper, comprising:
- a metal plate having a first pivot point, a forwardly extending blade and a rearwardly extending tang provided with a second pivot point spaced apart from the first pivot point by a predetermined distance;
- a first elongated member pivotally connected to the plate at the first pivot point, the first member having a forwardly extending jaw configured to cooperate with the blade to sever a workpiece received in a bight formed by the jaw, a rearwardly extending arm, and a first gear segment intermediate the jaw and the arm;
- and
- a second elongated member having a rearwardly extending portion and an opposed second gear segment, the second member being pivotally connected to the plate at the second pivot point so that the first and second gear segments are intermeshing in first and second regions, respectively;
- wherein the second gear segment is configured such that a second distance separating the second pivot point from the second region is smallest at a predetermined point of blade travel across the bight.
A variable force lopper, comprising:
- a metal plate having a first pivot point, a forwardly extending blade and a rearwardly extending tang provided with a second pivot point spaced apart from the first pivot point;
- a first elongated member pivotally connected to the plate at the first pivot point, the first member having a forwardly extending jaw configured to cooperate with the blade to sever a workpiece received in a bight formed by the jaw, a rearwardly extending arm, and a first gear segment intermediate the jaw and the arm;
- a second elongated member having a rearwardly extending portion and an opposed second gear segment, the second member being pivotally connected to the plate at the second pivot point so that the first and second gear segments are intermeshing in first and second regions, respectively;
- and
- means for imparting a variable cutting force to the workpiece as the blade travels across the bight.
A variable force pivoted tool, comprising:
- a first elongated member having a forwardly extending first jaw merging into a first gear segment, a first handle mounted onto an arm extending rearwardly from the first gear segment, and a first aperture formed in a region of the first gear segment;
- a metal plate having a forwardly extending cooperating jaw, a rearwardly extending tang and a second aperture intermediate the cooperating jaw and the tang, the tang being provided with a third aperture spaced apart from the second aperture by a predetermined distance, the metal plate being pivotally connected to the first member at a first pivot point comprising the first and second apertures;
- and
- a second elongated member having a second gear segment and a second handle mounted onto a portion extending rearwardly from the second gear segment, the second gear segment having a fourth aperture, the second member being pivotally connected to the plate at a second pivot point comprising the third and fourth apertures;
- the first and second gear segments intermeshing in first and second regions, respectively, and being configured so that a first distance separating the first pivot point from the first region and a second distance separating the second region from the second pivot point vary in equal but opposite amounts as the first and second handles are pivoted about the first and second pivot points, respectively.
Dependencies are inferred from the claim text.