US3470613A - Hedge shears - Google Patents

Description

1 Get. 7, 1969 D. H. KEISER JR 3,

HEDGE SHEARS Filed April 6, 1967 IN VENTOR.

DAVID HOWARD KEISERJF .his ATTORNEY United States Patent 3,470,613 HEDGE SHEARS David Howard Keiser, Jr., 53 Park Road, Wyomissing Hills, Pa. 19610 Filed Apr. 6, 1967, Ser. No. 628,884 Int. Cl. B26b 13/00 US. Cl. 30-268 3 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a pair of garden shears having blades which cant slightly in response to resistance to shearing to elfect greater efliciency in cutting during the shearing operation.

This invention relates to a pair of shears for cutting grass, twigs and the like. More particularly, this invention relates to a type of shears having one blade which is canted and moves sidewise with respect to the other so as to elfect greater contact pressure and cutting action during the shearing operation. This invention is an improvement over my prior Patent No. 2,661,534.

An object of my invention is to provide a device having an improved mounting means for one of the blades thereof to effect a positive, combined canting and shearing movement during its operation relative to the other blade.

Another object of my invention is to provide a device which will produce a maximum shearing action with the exertion of a minimum of effort by the operator.

Other objects and advantages will become more apparent from a study of the following description taken with the accompanying drawings wherein:

FIG. 1 is a top or plan view of a pair of grass shears embodying the present invention;

FIG. 2 is a side view thereof, partly in cross section; and

FIG. 3 is an enlarged, fragmentary perspective View.

Referring more particularly to FIG. 1 of the drawing, a pair of shears, generally denoted by numeral 1, is comprised of an integral blade and handle unit 2 pivotally mounted on a stud element 3 located intermediate the ends of the unit and secured by a nut 16 and a cotter pin 17 located beneath shear 1. The blade portion of unit 2 is normally made of forged metal while the handle section may be of wood or other suitable material.

A second handle element is pivoted on stud 3, and is loosely connected to a second blade 4 by connecting elements 5, 6, 8, 9 and 14. Sufiicient clearance is provided in the bearings of the handle 10 and blade 4 to permit these members to slightly cant on the pivot stud 3. Normally, however the blade 4 and handle 10 are yieldingly held against the inner end of the stationary blade 2 by means of a spring 9 and a nut 16 which is threaded to the stud 3. This yielding pressure is not great enough to firmly hold the blades 2 and 4 in a predetermined set position relative to each other but is calculated to yield Whenever the handle 10 is moved to operate the blade 4 through connecting elements 5, 6, 8, 9 and 14.

These connecting elements are comprised of a pair of lugs 14 which mount a pivotal shaft 8. Rocker arm 6 is attached at one end to blade 4 and at its other end, by spring means 9, to the second handle 10. Rocker arm 6 is pivoted about shaft 8 so as to efiiect a double motion of the second blade, namely a slight tilting away ice from the stationary blade when no resistance is present between the blades, and a slight canting toward the stationary blade during the shearing operation.

A camming pin 5 is mounted on rocker arm 6. A threaded stop element 11, mounted in a threaded hole in a flanged portion of second handle 10, is adjustably positioned manually by turning knurled head 12 so as to contact the rounded head of camming pin 5.

Stop element 11 is always in contact with camming pin 5. When shear blade meets resistance during the cutting movement, the pressure on camming pin 5 and stop element 11 increases proportionally and substantially causing camming pin 5 to slip or move upward in relation to stop element 11 causing the blades of same shear to tighter contact of blades. Stop element 11 is mounted off center in relation to camming pin 5 to effect this slipping movement; immediately after the cut is finished, the contact points 5 and 11 resume their normal position in relation to each other. This is altogether different from ordinary stop action where both faces would be flat and no movement would be possible, up or down.

During the shearing operation, as second blade 4 cants slightly in response to the resistance of the article being sheared, rocker arm 6 and camming pin 5 will rotate slightly, causing the end of stop element 11 to move radially outwardly of pin 5 and, by frictional force resulting from said contact, to resist the return of the blade to its normal loose position until the resistance to the shearing has been eliminated, that is, until the object to be sheared has been cut.

Thus it can be seen that I have invented an improved and highly efiicient shearing device which produces a maximum shearing pressure and cutting action with little effort through the action of a series of connecting elements which effect and sustain canting action of one of the blades during the shearing operation.

While I have illustrated and described a single embodiment of my invention, it will be understood that this is by way of illustration, and that various changes and modifications may be made within the contemplation of my invention and within the scope of the following claims.

I claim:

1. Hedge shears comprising an integral handle and blade unit, a pivot stud intermediate the ends of said unit, a second handle having an extension pivoted on said pivot stud, a pair of upstanding, integral bearings on the end portion of said extension, a rocker arm pivotally mounted on said bearings, a second blade, one end of said rocker arm being rigidly secured to the rear edge of said second blade, a spring interposed between the other end of said rocker arm and said extension for yieldably resisting lifting movement of said second blade from said first mentioned blade about said bearing pivotal mounting, a camming element on the side of said other end of the rocker arm, and a stop element mounted on said extension and being in contact with said camming element.

2. Shears as recited in claim 1 wherein said stop element is in the form of an upstanding integral projection from said extension having a threaded hole extending parallel to said blades through which a bolt extends in threaded relationship with its end engaging said camming element to provide an adjustable stop.

3. Shears as recited in claim 1 wherein said camming element is in the form of a rounded bolt head which 3 moves substantially radially in relation to said stop e1ement to increase the frictional resistance therebetween as cutting resistance increases.

References Cited UNITED STATES PATENTS 1,005,606 10/1911 Craig 30266 2,840,906 7/1958 Kciser 30-268 2,958,944 11/ 1960 Wertepny 30-248 3,323,210 6/ 1967 Dorney 30248 3,325,896 6/1967 DAngelo 30-248 5 ROBERT C. RIORDON, Primary Examiner J. C. PETERS, Assistant Examiner

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