Cutting blade edge construction for mechanically actuated shears
First Claim
1. A cutting apparatus comprising:
- a. a mechanical drive source;
b. mounting means for said drive source; and
c. a pair of planar cutting blades having a predetermined number of coacting cutting edges for cutting material caught therebetween, said blades being mounted on said mounting means for repetitive relative movement and having a drive connection to said drive source whereby the respective coacting edges of said blades move in a repetitive angular relation and repetitively execute cutting actions, said coacting edges being shaped such that during each such cutting action the contacting cutting point between each pair of coacting edges moves at a uniform
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Accused Products
Abstract
Pairs of planar cutting blades with angularly related cutting edges such as are used in grass shears, and the like, and which are mechanically actuated to move relative to each other and to cut by a scissors-like action are formed in a manner such that during each cutting action the contacting cutting point between each pair of coacting edges moves at a uniform speed. The improved blade construction finds application in shears, particularly cordless, i.e., battery, grass shears, by more nearly equalizing incremental power requirements; by reducing the maximum input power requirements; and by increasing time of performance between battery recharging at a given forward advancement speed of the shear.
29 Citations
18 Claims
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1. A cutting apparatus comprising:
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a. a mechanical drive source; b. mounting means for said drive source; and c. a pair of planar cutting blades having a predetermined number of coacting cutting edges for cutting material caught therebetween, said blades being mounted on said mounting means for repetitive relative movement and having a drive connection to said drive source whereby the respective coacting edges of said blades move in a repetitive angular relation and repetitively execute cutting actions, said coacting edges being shaped such that during each such cutting action the contacting cutting point between each pair of coacting edges moves at a uniform - View Dependent Claims (2, 3, 4, 5, 6)
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7. In a portable shear adapted to shearing a width of growing material including grass, shrubbery, and the like, of the type having:
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a. a housing having an electric motor disposed therein; b. a first cutting blade having a plural number of cutting teeth and extending forwardly from said housing; c. a second cutting blade having a plural number of cutting teeth and extending forwardly from said housing, said blades being positioned to mate the respective said teeth for relative movement in a repetitive angular relation for operative shearing action; and d. drive means mounted in said housing and connecting said motor to drive at least one of said blades whereby said first blade teeth are reciprocated relative to said second blade teeth to cause the respective coacting tooth edges to execute repetitive said shearing actions while said relative movement proceeds at a non-uniform speed;
the improvement comprising;e. the coacting cutting edges of said teeth being shaped such that while said relative movement proceeds at said non-uniform relative speed, the contact cutting point between each pair of coacting edges of said teeth moves at a uniform speed during each such shearing action performed - View Dependent Claims (8, 9, 10, 11, 12)
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13. A portable shear comprising;
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a. a housing having a motor disposed therein; b. handle means secured to said housing; and c. a pair of planar blades having a predetermined number of coacting cutting edges for shearing material caught therebetween, said blades being mounted on said housing for repetitive relative movement and having a drive connection to said motor whereby the respective coacting edges of said blades move in a repetitive angular relation and repetitively execute cooperative shearing actions, said coacting edges being shaped such that during each such shearing action the contacting cutting point between each - View Dependent Claims (14, 15, 16, 17, 18)
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Specification