US3913227A

US3913227A - Mild-steel cutter

Info

Publication number: US3913227A
Application number: US515519A
Authority: US
Inventors: William Francis Shurtleff
Original assignee: Individual
Current assignee: Individual
Priority date: 1974-02-26
Filing date: 1974-10-17
Publication date: 1975-10-21
Anticipated expiration: 1992-10-21

Abstract

A new type, hand-operable cutting tool for cutting objects comprising mild steel rods, characterized by a base structure having a base handle and a first cutting jaw rigidly connected therewith; a second cutting jaw that is pivotally mounted adjacent the first cutting jaw via a compound linkage arrangement so as to be reversibly movable toward, along and into engagement with the first cutting jaw in a motion that has a slicing component, as well as shearing component; and a second handle that is pivotally connected with the base handle and has a leverage multiplying means for applying a force of large magnitude and having slicing and shearing components to the second cutting jaw responsive to movement of the handles together. Also illustrated and described are additional structural details of a preferred embodiment.

Description

[ 1 Oct. 21,1975

1 1 MILD-STEEL CUTTER William Francis Shurtleff, White Settlement, Tex,

22 Filed: Oct. 17, 1974 21 Appl. NO.I515,519

Related U.S. Application Data [63] Continuationin-part of Ser. No. 411,180, Feb. 26,

1974, abandoned.

[76] Inventor:

Primary ExaminerAl Lawrence Smith Assistant Examinerl, C. Peters AI10rney,Agem,ur Firm-James C. Fails [57] ABSTRACT A new type, handoperable cutting tool for cutting ob jects comprising mild steel rods, characterized by a base structure having a base handle and a first cutting jaw rigidly connected therewith; a second cutting jaw that is pivotally mounted adjacent the first cutting jaw via a compound linkage arrangement so as to he re versibly movable toward, along and into engagement with the first cutting jaw in a motion that has a slicing component, as well as shearing component; and a second handle that is pivotally connected with the base handle and has a leverage multiplying means for applying a force of large magnitude and having slicing and shearing components to the second cutting jaw responsive to movement of the handles togetherv Also illustrated and described are additional structural de tails of a preferred embodiment,

1 Claim, 3 Drawing Figures MILD-STEEL CUTTER CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 411,180, of the same title, filed Feb. 26, 1974, abandoned as of the filing date accorded this application.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to hand operable cutting tools. More particularly, this invention relates to a cutting tool for cutting objects, such as mild steel rod or the like, with only one hand; thereby leaving the other hand of the worker free to grasp the cut-off portion of the object.

2. Description of the Prior Art A wide variety of cutting tools have been known in the prior art. These constructions have included cutting pliers, bolt cutting devices and the like. Prior art devices have suffered from one or more of the following disadvantages, however. If they were operable to cut an object larger than wire or the like, they could not be operated with only one hand. The reasons were: (1) because adequate power could not be generated without long handles and a large amount of leverage thereby requiring both hands to operate; or (2) the cutters were progressive cutters that required stages of operation, with holding ratchets or the like.

When a workman such as a brick layer has to operate both hands to cut a mild steel rod, such as is employed in the reinforcing used with the tile or bricks, a cut-off portion falls away. Consequently, the worker is slowed down.

Specifically, the prior art devices did not have a compound lever action that enabled cutting mild steel rods or the like with a load effort low enough to be operable with only one hand, even on short handles that are so operable.

SUMMARY OF THE INVENTION Accordingly, it is an object of this invention to provide a light weight cutting tool that requires only one hand operation, yet can be employed to cut objects as difficult to cut as mild steel rods.

Still another object of this invention is to provide a device of the type described by which long rods of metal can be held by one hand while being cut by the other hand, thereby saving the workmans time.

It is a specific object of this invention to provide a cutting jaw that is moved in the cutting operation by a compound lever action that effects both shearing and slicing for much easier cutting operation so as to accomplish the objects delineated hereinbefore.

Additional objects and advantages of the present invention will become apparent from the following description, particularly when taken in conjunction with the accompanying drawings.

In accordance with this invention, there is provided a cutting tool characterized by a base structure that is fixedly connected with a base handle and a first cutting jaw. A second cutting jaw is pivotally mounted adjacent the first cutting jaw via a compound linkage arrangement so as to be reversibly movable toward, along, and into engagement with the first cutting jaw in a motion that has a slicing component, as well as a shearing component; thereby enabling cutting with only one hand elongate metallic objects that heretofore required both hands of a worker. A second handle is pivotally mounted with respect to the base handle and has a leverage multiplying means for applying force of a large magnitude for inducing the slicing and shearing action to the second cutting jaw. The cutting jaws have respective cutting edges that are contiguous each other in the closed position and have high strength thick portions for transmitting large forces for effecting the slicing and shearing cutting.

In the preferred embodiment, the compound linkage arrangement includes a pair of links on each side of the respective cutting jaws and handles for balanced force transmission. Also preferably, the second handle is pivotally mounted so as to apply the leverage multiplying means adjacent the movable end of the second cutting jaw for effecting a large force on the object to be cut.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of the cutting tool of this invention.

FIG. 2 is a side elevational view of the cutting tool of FIG. 1.

FIG. 3 is a side elevational view, with the front plate and link removed to illustrate, somewhat schematically, the slicing and shearing action of the second cutting jaw in being moved contiguous the first cutting aw.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the figures, the cutting tool 11 comprises a base structure 13 having a base handle 15 and a base cutting jaw 17 rigidly and fixedly connected therewith. As illustrated, the base structure 13 also includes a pair of

side members

19 and 21 that are disposed on each side of the first cutting jaw 17 and the base handle 15. As illustrated in FIG. 3, the central portion of the base structure 13 is integral with the base handle 15 and the first cutting jaw 17. The center portion of the base structure 13 and the base handle 15 are preferably formed of a strong material such as a high strength alloy of steel, magnesium or the like.

The base handle 15 may comprise a conventional handgrip handle such as employed with pliers or the like, and extends from the central portion of the base structure 13 rearwardly, or to the right in the illustrated drawings. Ordinarily, it is preferably knurled where it will be gripped by the hand of the workman.

The first cutting jaw 17 has a first cutting edge 23 and a supporting high strength structure 25. The first cutting edge 23 is preferably formed of a hard material that is capable of shearing and slicing into a mild steel rod or the like. Suitable hard materials include relatively economical materials such as hardened steel, silicon carbide, or the like; and expensive materials like diamond, corundum, and the like. The high strength portion 25 has adequate structural strength to afford a reaction force sufficient to resist the force imparted onto the first cutting edge 23 by a mild steel rod or the like that is being cut. A second cutting jaw 27 is pivotally mounted adjacent the first cutting jaw 17. The second jaw 27 has a second cutting edge 29 and a high strength thick portion 31 for transmitting large forces for forcing the second cutting jaw in a shearing and slicing motion through the material to be cut, so as to em place the second cutting edge 29 contiguous the first cutting edge 23 of the first cutting jaw 17. The second cutting edge, similarly as described hereinbefore with respect to the first cutting edge 23, is formed of a hard material for slicing and shearing through the material; such as. mild steel rod; to be cut. The high strength por tion 31 may be formed of structural steel or other high strength alloy.

The second cutting jaw 27 has a recess, or notch, 30 that engages a high strength protrusion 32 on the first cutting jaw 17. Consequently, the second cutting jaw is constrained to a limited slicing and shearing trajectory to place its cutting edge 29 contiguous the cutting edge 23 of the first cutting jaw 17. The motion is compound, however, and requires a compound linkage arrangement.

A compound linkage arrangement 33 connects the second cutting jaw 27 with the base structure 13 such that the second cutting jaw 27 is reversibly movable toward. along and into engagement with the first cutting jaw in a motion that has a slicing component, as well as a shearing component. Because of the compound linkage arrangement and the combined slicing and shearing action, the second cutting jaw cuts through an object with a lower force. The improved result effected is analogous to low force slicing through bread or a tomato, in contrast to high force pure shear mg.

Specifically, the compound linkage arrangement 33 includes a pair of links 35 and 37 having base ends 39 and movable ends 41. The links 35 and 37 are mounted on each side of the base structure. As illustrated they are mounted laterally exteriorly of the

side members

19 and 21. By having the links on each side, balanced forces are transmitted to eliminate binding and facilitate the requisite compound pivotal movement of the second cutting jaw 27. A base shaft 43 comprising a bolt and nut 45 retains the links 35 and 37 and the

side members

19 and 21 connected to the center portion of the base structure 13; but allows pivotal movement of the links 35 and 37 about the base shaft 43.

The compound linkage arrangement 33 also includes a jaw shaft 47 comprising a bolt and nut 49. Bolt with nut 49 penetrates through the non-cutting end 51 of the second cutting jaw 27 and through the movable ends 41 of the links 35 and 37 such that the second cutting jaw 27 can be forced to pivot about the jaw shaft and toward the first cutting jaw 17 for shearing movement and simultaneously pivot about the base shaft 43 for slicing movement. To accommodate the pivotal movement of the links 35 and 37 and jaw shaft 47 about the base shaft 43, each of the

side members

19 and 21 has an arcuate slot 53.

The cutting tool 11 includes a second handle 55 that is pivotally carried by the base structure 13 for movement with respect to the base handle 15. As illustrated, the second handle 55 is mounted for pivotal movement about shaft 57, comprising a bolt and nut 59. The second handle 55 has connected therewith a leverage multiplying means 61 for applying to the second cutting jaw 27 a force having large magnitude and having slicing and shearing components. The force is applied responsive to movement of the second handle 55 relatively toward the base handle 15. As illustrated, the leverage multiplying means comprises a protrusion 63 that frictionally engages the thick portion 31 of the sec ond cutting jaw 27 for applying the large force to the movable end 65 of the second cutting jaw 27.

An adjustment means, including nut 67 and set screw 69 is provided to allow compensation for wear. Specifi cally, the nut 67 is trapped in the

sides

19 and 21, forming part of the base structure, and allows the set screw 69 to be screwed downwardly. This pivots the first cutting jaw 17 upwardly about the base shaft 43, since the bolt 70 can move downwardly in slot 72, FIG. 3. Consequently, the first cutting jaw 17 is disposed more closely adjacent, or contiguous, the second cutting jaw 27 to compensate for wear of the cutting jaws with extended use.

The second handle 55 and the protrusion 63 is preferably formed of a high strength structural alloy such as steel, magnesium or the like. If a soft high strength metal, such as magnesium, is employed for the protrusion 63, it is preferably faced with a hard facing such as Stellite, silicon carbide, or the like.

ln operation, the

handles

15 and 55 are open, as illustrated in solid lines in FIG. 3 and the material, such as a mild steel rod 81 in tile reinforcing, is inserted intermediate the first and second cutting edges 23 and 29 of the first and second cutting

jaws

17 and 27. The second handle 55 is forced downwardly by one hand, the fingers pulling against the base handle 55. As the second handle 55 moves downwardly, the protrusion 63 progresses against the movable end 65, specifically the top of the thick portion 31 in the illustrated figures. The protrusion 63 serves as a leverage multiplying means because of its close proximity to the fulcrum shaft 57 to enable applying a very large force to the second cutting jaw 27 by a nominal force at the rear extremity of the second handle 55. The compound linkage arrangement 33 pivots about the shaft 43, simultaneously allowing second cutting jaw 27 to pivot about the jaw shaft 47. Consequently, the second cutting jaw 27 is forced in the direction of the arrow 71, not in a purely arcuate path illustrated by the dashed lines 73. As illustrated by the arrow 75, the arrow 71 has a slicing component parallel with the longitudinal axis of the first cutting edge 23 for inducing the slicing movement, as well as the shearing movement, depicted by a vertical component of the arrow 71. As a result, the material to be cut is severed more easily and with less force required on the short handles.

Further movement of the second handle 55 toward the base handle 15 continues the application of the force of the necessary magnitude to effect the combination shearing and slicing action on the object to be cut. Because of the combination of the leverage multiplying means, and the combined slicing and cutting action, the object can be cut readily with a single hand, allowing the workman to hold the object in his other hand, thereby saving time of a skilled workman.

The cutting tool 11 is lightweight and may be readily stored in a pocket or a pouch of the workman for subsequent use when another object is to be cut.

The cutting tool 11 has been found to be useful in prolonged service with relatively little wear. When there is wear, however, the bolt 67 may be moved to allow the handles to be moved more closely together to continue to apply the necessary force to the second cutting edge 27.

While the center portion of the base structure 13, the base handle 15 and the first cutting jaw 17 have been illustrated as a unitary structure, the respective portions may be rigidly connected together by two or more rivets. bolts or the like to effect the same results. Moreover, they may be preformed separately and welded together into an integral structure if desired.

From the foregoing, it can be seen that this invention accomplishes the objects delineated hereinbefore. It has been found that the cutting tool 11 can save enough skilled workmens time to pay for itself in only one days working time. Consequently, there is a high demand for the cutting tool 11.

Although this invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of this invention as hereinafter claimed.

What is claimed is:

l. A cutting tool comprising:

a. a base structure;

U a base handle fixedly carried by said base structure;

a first cutting jaw rigidly connected with said base handle and having a first cutting edge and a supporting high strength portion;

. a second cutting jaw having a second cutting edge and a high strength thick portion adapted for transmitting large forces to said cutting edge; said second cutting jaw being pivotally mounted adjacent said first cutting jaw with said second cutting edge movable contiguous said first cutting edge while cutting an object;

. a compound linkage arrangement connecting said second cutting jaw with said base structure so as to be reversibly movable toward, along, and into engagement with said first cutting jaw in a motion that has a slicing component, as well as a shearing component, and thereby enable cutting with only one hand an elongate metallic object and the like that heretofore required both hands of a worker;

f. a second handle pivotally carried by said base structure for movement with respect to said base handle;

g. leverage multiplying means for applying to said second cutting jaw a force of large magnitude and having slicing and shearing components, said applying being responsive to movement of said base and second handles toward each other, said leverage multiplying means being connected to said second handle means and engaging said thick portion of said second cutting jaw for forcing said second cutting jaw towards said first cutting jaw with said large force having said shearing and slicing component;

said compound linkage arrangement comprising a pair of links having base ends and movable ends and mounted on each side of said base structure and pivotally movable about a shaft at their base ends; and a jaw shaft penetrating through a noncutting end of said second cutting jaw and through said movable ends of said pair of links such that said second cutting jaw can be forced to pivot about said jaw shaft, simultaneously pivot about said base shaft for slicing movement and move toward said first cutting jaw for severing of said object; said leverage multiplying means being disposed adjacent the end of said second cutting jaw opposite said non-cutting end thereof; said base structure in cluding a pair of sides, one on each side of said handles and cutting jaws; said pair of links being disposed exteriorly of said sides and an arcuate slot being cut through said sides to allow arcuate and pivotal movement of said jaw shaft about said base shaft for effecting said slicing and shearing movement of said second cutting jaw with respect to said first cutting jaw; such that a worker can cut through elongate metallic objects with one hand while employing the other to save the cut portion of said object, thereby conserving time of said worker.

Claims

1. A cutting tool comprising: a. a base structure; b. a base handle fixedly carried by said base structure; c. a first cutting jaw rigidly connected with said base handle and having a first cutting edge and a supporting high strength portion; d. a second cutting jaw having a second cutting edge and a high strength thick portion adapted for transmitting large forces to said cutting edge; said second cutting jaw being pivotAlly mounted adjacent said first cutting jaw with said second cutting edge movable contiguous said first cutting edge while cutting an object; e. a compound linkage arrangement connecting said second cutting jaw with said base structure so as to be reversibly movable toward, along, and into engagement with said first cutting jaw in a motion that has a slicing component, as well as a shearing component, and thereby enable cutting with only one hand an elongate metallic object and the like that heretofore required both hands of a worker; f. a second handle pivotally carried by said base structure for movement with respect to said base handle; g. leverage multiplying means for applying to said second cutting jaw a force of large magnitude and having slicing and shearing components, said applying being responsive to movement of said base and second handles toward each other, said leverage multiplying means being connected to said second handle means and engaging said thick portion of said second cutting jaw for forcing said second cutting jaw towards said first cutting jaw with said large force having said shearing and slicing component; said compound linkage arrangement comprising a pair of links having base ends and movable ends and mounted on each side of said base structure and pivotally movable about a shaft at their base ends; and a jaw shaft penetrating through a noncutting end of said second cutting jaw and through said movable ends of said pair of links such that said second cutting jaw can be forced to pivot about said jaw shaft, simultaneously pivot about said base shaft for slicing movement and move toward said first cutting jaw for severing of said object; said leverage multiplying means being disposed adjacent the end of said second cutting jaw opposite said non-cutting end thereof; said base structure including a pair of sides, one on each side of said handles and cutting jaws; said pair of links being disposed exteriorly of said sides and an arcuate slot being cut through said sides to allow arcuate and pivotal movement of said jaw shaft about said base shaft for effecting said slicing and shearing movement of said second cutting jaw with respect to said first cutting jaw; such that a worker can cut through elongate metallic objects with one hand while employing the other to save the cut portion of said object, thereby conserving time of said worker.