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US 8,046,924 B2Granted
Cutting tool with variable mechanical advantage
AssigneeFiskars Brands, Inc.
InventorsAndrew Block, Scott Roelke
Life of this patent
Estimating the term…
Abstract
A hand-operated cutting tool includes first and second cutting members pivotally connected at a first pivot point, a lever having a longitudinal axis and pivotally connected to the first cutting member at a second pivot point, and a translatable curvilinear pivot connection between the lever and the second cutting member.
Claims14
A hand-operated cutting tool comprising:
- a first cutting member including first and second apertures;
- a second cutting member including a third aperture, the second cutting member at least in part overlying the first cutting member with the third aperture in general registry with the first aperture;
- a lever having a longitudinal axis, and including a fourth aperture and an arcuate slot, the arcuate slot having a first end center point and a second end center point, and the longitudinal axis extends through the arcuate slot and a center point of the fourth aperture;
- a first pivot connection between the cutting members at the first and third apertures;
- a second pivot connection between the lever and the first cutting member at the second and fourth apertures;
- a projection disposed on the second cutting member and extending through the arcuate slot for effecting a point of interaction between the lever and the second cutting member;
- wherein a line extending between the center point of the fourth aperture and the first end center point of the arcuate slot defines a first angle with the longitudinal axis;
- wherein a line extending between the center point of the fourth aperture and the second end center point of the arcuate slot defines a second angle with the longitudinal axis;
- and
- wherein the second angle is greater than the first angle.
7 more elements
A handle-operated cutting tool comprising:
- first and second cutting members pivotally connected at a first pivot point;
- a lever having a longitudinal axis and pivotally connected to the first cutting member at a second pivot point;
- a curved slot disposed on the lever, the curved slot defining a first end center point and a second end center point, and the longitudinal axis of the lever extending through the curved slot and the second pivot point;
- a projection disposed on the second cutting member and slidable in the curved slot for effecting a point of interaction between the lever and the second cutting member throughout a cutting stroke;
- wherein a line extending between the second pivot point and the first end center point of the curved slot defines a first angle with the longitudinal axis, and a line extending between the second pivot point and the second end center point of the curved slot defines a second angle with the longitudinal axis;
- and
- wherein the second angle is greater than the first angle.
4 more elements
A hand-operated cutting tool, comprising:
- first and second cutting members pivotally connected at a first pivot point;
- a lever having a longitudinal axis and pivotally connected to the first cutting member at a second pivot point;
- a translatable curvilinear pivot connection between the lever and the second cutting member, the translatable curvilinear pivot connection comprising a curved slot on one of the lever and the second cutting member and a projection disposed on the other of the lever and the second cutting member, and the curved slot defining a first end center point and a second end center point;
- wherein a line extending between the second pivot point and the first end center point defines a first angle with the longitudinal axis, and a line extending between the second end center point and the second pivot point defines a second angle with the longitudinal axis, with the second angle greater than the first angle;
- wherein the projection is disposed proximate the first end center point of the curved slot to provide a maximum mechanical advantage when the cutting members are in a cutting stroke position within a range of approximately 55 to 65 percent travel;
- and
- wherein the projection is disposed proximate the second end center point when the cutting members are in a full open position.
4 more elements
Dependencies are inferred from the claim text.