JPH021606B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to the cutting of sheet material or similar material in a straight line or right or left direction, including cutting into opposing circles with a minimum radius of approximately 5.08 cm to 6.35 cm. Improved manual offset scissors used for cutting.

(Prior Art) When cutting sheet metal or similar materials with conventional scissors, one or both edges of the cut sheet material may interfere with the body of the scissors, causing the scissors to cut into the sheet material. It becomes difficult to move forward,
This will distort the cut edge. This interference is greatest when cutting irregular shapes, especially sharp curves and especially small circles. Conventional scissors are therefore often presented in a plane-symmetrical shape that is specifically adapted to making cuts that curve to the left or to the right. Also, when conventional scissors are used to cut thick, stiff materials, the sheet material tends to slip off the blade when the blade is closed, reducing cutting efficiency. Additionally, conventional scissors require long handles and require the operator to use significant force to cut multiple sheets of material.

One attempt to reduce interference of the cut sheet material with the scissor body is to have the cut sheet material pass through one side of the handle, as shown in U.S. Pat. The cutting surface is offset from the handle of the scissors. It is also implemented in that patent to extend the cutting blade laterally approximately at right angles to the point of action of the handle. This shape makes it easier for the scissors to advance through the sheet material by reducing the vertical extent to which the cut sheet material passes above and below the lower blade, allowing the sheet material to move away from the cutting surface. It reduces the tendency to slip. More recently, linkage devices, such as those shown in U.S. Pat. No. 3,587,173, have been proposed to reduce the force required from the operator to cut strong sheet materials.

As with traditional scissors, most available offset scissors are generally only usable for cutting curves, either to the left or to the right, unless they are cutting curves in the opposite direction. If this is not possible, other offset scissors with a bisymmetrical shape will be required. Additionally, the laterally extending blades of commercially available offset scissors must be carefully ground and adjusted during the manufacturing process, and cannot be conveniently resharpened if the blades become dull or damaged. If the blade is used incorrectly by cutting wire or the like, the scissors will not be able to cut the sheet material. Therefore, there is a need for improved offset scissors, including scissor-type or shear-type wire cutters, that can be easily resharpened if the blades become dull or damaged. Additionally, there is a need for an improved handle and toggle device or configuration that makes offset scissors more powerful and easier to use when cutting corrugated sheet materials.

In the inventor's related United States patent application:
A pinch-type cutter is used in which part of the upper blade acts as a pincushion and part of the lower blade acts as a chisel for wire cutting. For such devices, there is a "relief" formed at the base of the cutter blade due to the manufacturing process of the cutter blade, so that the wire to be cut can be clearly cut at the position of the cutter blade, That is, it needs to be located substantially in the center. For example, if a small diameter piece of gold is placed at the base of a katsuta, it will essentially be located in the ``relief'' part of the katsura, and will not touch the blade of the katsura, and the wire will be placed at the ``relief'' part of the katsuta. This will prevent it from being cut. This "relief" is formed as a result of the various grinding operations or passes required to grind both sides of the chisel. Also, in forming the chisels of the above-referenced patent applications, the grinding passes generally produce wide V-shaped chisels with an angle between the two sides of the chisel of about 70 degrees. Although such an angled chisel shape is preferred for most applications, it makes the manufacturing process more difficult and adds significant manufacturing costs. Also, because the chisel has a wide cutting angle, it requires a lot of pressure and force to cut the wire, and small diameter wire, or even larger diameter wire, easily cuts into the "runout" area at the base of the chisel. I get stuck and can't move. When this happens, the wire becomes difficult to cut, and to ensure a reliable cut, it is necessary to carefully cut the wire so that the blade of the cutter does not get stuck in the "escape" area. The wire must be re-centered by hand so that the chisel can be cut or pinched across the entire width of the wire.

Another drawback of our related patent application is that although the lower blade member is not offset, it does not have adequate clearance to make opposing circular cuts of very small radius.
This drawback requires the manufacture and provision of both left-handed and right-handed cutters. This is because no offset scissors are considered to be true all-purpose scissors capable of cutting in either direction, i.e., straight, to the right, and to the left. In most applications, an arc of at least approximately 5.08 to 6.35 centimeters in diameter;
Cutting curves or circles can meet tooling needs in most fields.

(Problem to be Solved by the Invention) It is therefore an object of the present invention to cut sheet material into circles of only a very small radius, without the cut material being hindered by interference with the body of the scissors. It can be cut into left and right curves. An object of the present invention is to provide improved all-purpose offset scissors.

Another object of the present invention is that even if the cut surface becomes dull or damaged, it can be easily and economically resharpened, and the chisel of a wire cutter can be resharpened once together with the boss of the blade member. The object of the present invention is to provide a powerful and improved all-purpose offset scissor that can be achieved only by a grinding pass.

Still another object of the present invention is to have a scissoring or shearing means for cutting wire, etc., thereby eliminating the need for a second tool and eliminating the need for improper cutting of the sheet material of the offset blade member. The object of the present invention is to provide an improved all-purpose offset scissor that can reduce usage.

Still another object of the present invention is to provide a toggle arrangement that provides greater force to the central toggle axis of a dual/triple pivot point toggle linkage in which the toggle axis points are generally straight when the offset scissors are in the closed position.
An object of the present invention is to provide improved universal offset scissors with substantially greater force.

Yet another object of the invention is to provide a universal offset with a handle having a significantly greater force toggle ring device, which allows the scissors to be more easily grasped when in the open position and more easily brought to the closed position. The purpose is to provide scissors.

Still another object of the present invention is to have a scissor or shear type cutter, in which, regardless of the type of cutter used, the knuckle of the scissor cutter is on the upper blade member and the chisel is on the lower part. To provide a universal offset scissor on a blade member.

Still another object of the present invention is to provide a universal offset scissor having a chisel that can be sharpened in one grinding pass along with the boss of the blade member and capable of cutting across the entire width of the pinion. be.

SUMMARY OF THE INVENTION The present invention is an improvement in manual universal scissors with full-width wire cutting means for cutting sheet material and wire or other rod-like materials.

According to a first feature of the invention, the first and second
The blade member has a pivot mounting boss whereby the pivot means pivotally couples the blade member to rotate about an axis perpendicular to the pivot mounting boss. Each blade member has first and second cutting surfaces, the first and second cutting surfaces being offset relative to the plane of each pivot mounting boss. Rotation of the blade member about the pivot means moves the first and second cutting surfaces between the open and closed positions to cut the sheet material therebetween. The pivot mounting bosses and cutting surfaces are adapted to allow material to be removed, thereby allowing the cutting surfaces to be resharpened while maintaining the offset between each pivot mounting boss and the cutting surface. At the same time as the chisel of the wire cutter is being resharpened, the pivot mounting boss is also ground to the desired size. The offset of the cutting surface relative to the pivot mounting boss is a minimum of approximately 0.635 cm to 0.953 cm to allow previously cut material to pass through the blade member without interference and to cut even very small diameter opposing circular cuts. .

According to another feature of the invention, the first and second blade members are rotatably coupled via the handle portion. One of the handle portions is provided with a recess substantially in the plane of the sheet material to be cut. Each blade member has first and second cutting surfaces, and the first and second cutting surfaces are formed with an offset extending relative to the handle portion to cut the sheet material therebetween. Rotate between open and closed positions to The cut edge of the cut sheet material is received within the recess to permit cutting of the sheet material along leftward and rightward curves. As a result, the offset scissors of the present invention are "all-purpose" and eliminate the need for separate right-handed and left-handed scissors when irregular cuts are required.

According to another feature of the invention, the handle is pivotable in order to provide particularly favorable toggle leverage throughout the cutting stroke, whereby the center of the force is generated in order to achieve a strong locking of the tool. The toggle point of is achieved by making the movement of the toggle position over the center substantially linear;
The pivot bolt articulates the blade member relative to the handle.

Other features of the invention include improved integral cutting means suitable for cutting wire and integral locking means for maintaining the cutting blade in a closed position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, one embodiment of offset scissors according to the present invention is designated at 10 in FIGS. 1-3. Cutting shears 10 have upper and lower blade members designated 12 and 14, respectively. Upper and lower blade members 12 and 1
4 is rotatable about the main pivot bolt 16 by means of upper and lower handles designated 18 and 20, respectively. The blade member 12 is inserted between the open position shown in FIG. 1 and the closed position shown in FIG.
and 14, the sheet-like material to be cut 22 or the wire-like material to be cut 2 placed between the blade members 12 and 14 as shown in FIG.
4 cuts are made.

The handles 18 and 20 are rotatable about a handle pivot bolt 26 located intermediate between the ends of the handles 18 and 20. The rear portions 28 and 30 of each handle 18 and 20 are covered by upper and lower grips 32 and 34, respectively. Preferably, grips 32 and 34
are formed by dipping or molding to have outwardly projecting ear portions 36 and 38, respectively, to prevent the operator's hands from slipping forward during use of the cutting shears 10. Preferred materials for grips 32 and 34 are manufactured by Sinclair, St. Louis, Missouri.
Heat soak plastisols such as those available from Sinclair Rush.

Handles 18 and 20 extend forwardly and away from each other from handle pivot bolt 26 to connect blade members 12 and 14 with pivot bolts 40 and 42.
It is designed to be rotatably mounted. 1st
In the open position shown in the figure, preferably the pivot bolt 2
An acute angle is formed between an imaginary line connecting pivot bolts 26 and 42 and an imaginary line connecting pivot bolts 26 and 42.
Preferably, handles 18 and 20 have a U-shaped cross section defined by laterally spaced sides 44 and 46 joined by a web portion 48, as shown in FIG. Handle pivot bolt 26
An omega spring 50, held in place by the handles 18 and 20, engages the web portions 48 of the handles 18 and 20 to bias the cutting shears 10 to the open position. Other biasing means can also be used as long as they have similar effects. Sleeve 51 is disposed between handle pivot screw 26 and omega spring 50 to center and space omega spring 50 relative to handle pivot screw 26. Although the sleeve 51 is not essential to the operation of the cutting shears 10, the inventors have found that the sleeve 51 substantially extends the cycle life of the omega spring 50. .

In the open position, the upper blade member 12 extends from the main pivot bolt 16 to the pivot bolt 40 as shown in FIG.
Extending upwardly and rearwardly over the upper pivotable mount. The lower blade member 14 is connected to the main pivot bolt 16
and extends rearwardly from the pivot bolt 42 to a pivotable mount on the pivot bolt 42. When handles 18 and 20 are closed, pivot bolts 40 and 42 rotate about handle pivot bolt 26, thereby spreading rear portions 54 and 56 of blade members 12 and 14. As shown in FIG. 3, the rear portions 54 and 56 have sufficient thickness so that the sides 44 and 46 of the handles 18 and 20 can be closely received, thereby allowing the upper and lower cutting blades 12 and 14 in alignment. Adjustment of the play between sides 44 and 46 and rear portions 54 and 56 is provided by adjustment nuts 58 on pivot bolts 40 and 42.

The main pivot bolt 16 is connected to the handle 62 of the upper blade member 12.
The handle 6 of the lower blade member 14 is screwed into the inner hole 60.
6 into the hole 64. Locking nut 6
8 is locked to the handle 62 and the main pivot bolt 1
Maintain the adjusted length of 6. Cutting surfaces 70 and 72 of cutting blades 12 and 14 lie in substantially parallel but laterally offset planes with adjacent handles 62 and 66 of each blade member, as shown in FIG. The offset is the sheet-like material to be cut 2.
The cut portion 2 can be passed through the side surface of the handle 66.

The present inventor has discovered that the cutting surfaces 70 and 72 are curved in side view so as to present a convex cutting surface to the object to be cut, as shown in FIGS. 4 and 7. It has been found that cutting of the object 22 to be cut is improved. In the preferred embodiment shown, the upper cut surface 70 is defined by a radius of 8 inches and the lower cut surface 72 is also defined by a radius of 8 inches. However, the illustrated shape is merely exemplary, as various other curved shapes can be used to achieve similar effects. As seen in FIGS. 4-8, the front portions 84 and 8 of each blade member 12 and 14
6 extends laterally generally perpendicular to the handles 62 and 66. Due to this shape, the workpiece 2 of sheet-like material placed on a flat surface such as a table, for example.
2 is facilitated and the cutting surface of the object to be cut is minimized from being spread out as it passes above and below the lower blade member 14.

Preferably, blade members 12 and 14 have surfaces 78 and 80 so that upper and lower cutting surfaces 70 and 72 have a uniform width in side view while accomplishing resharpening of the blade members as described below.
It is ground in a concave manner. Lower cut surface 7
A relief 82 is provided at the rear of 2 to facilitate sharpening of the cutting surface 72 and to ensure smooth sliding engagement of the cutting blades 70 and 72 during cutting.
The front portions 84 and 86 of the blade members 12 and 14 are inwardly curved to form convex surfaces as shown in FIGS. 6 and 9. This shape of the front portions 84 and 86 provides sufficient strength to the cutting blades 70 and 72 while allowing the shears 10 to be maneuvered for cutting where space is at a premium.

Cutting of the wire to be cut 24 is effected by engagement of a pinion 88 formed on the upper blade member 12 with a chisel or wedge portion 90 formed on the lower blade member 14. Kanatoko part 88 and wedge part 9
The position of 0 depends on the position of the cutting scissors 10.
is such as to form a stop that limits rotation of the blade member when in the closed position as shown in FIG. The wedge portion 90 has the cutting scissors 10 first.
A wire placed on the lance 88 when moving from the open position shown in the figure to the closed position shown in FIG.
Acts as a chisel for cutting rods, small bar materials, etc. Other opposed cutting blades, such as "diagonal" cutters, may be used in place of the latches 88 and wedges 90 to similar effect.

It is an important feature of the invention that cutting surfaces 70 and 72 can be reground to refurbish worn or damaged cutting surfaces. Referring to FIG. 3, polishing either the upper cutting surface 70 or the lower cutting surface 72 results in cutting surfaces 70 and 7.
It is generally expected that there will be a lateral space between the two, making it impossible to cut the sheet-like material to be cut 22. The offset of cut surface 70 relative to handle 62 is increased by such grinding. Therefore, once commercially available offset scissors become dull or damaged, they cannot be conveniently resharpened.

The re-grinding of the cutting scissors 10 of the present invention is performed by
and 66 by pivot mounting bosses 92 and 94, respectively.
The pivot mounting bosses 92 and 94 are attached to the main pivot bolt 1
6 protrudes above the surfaces of the handles 62 and 66 at right angles to 6. It is a flat protrusion. The pivot mounting boss 92 does not need to have any special shape, but for example, as shown in FIG. It may have the following. Similarly, the pivot mounting boss 94 has, for example, a semicircular front portion 1 concentric with the main pivot bolt 16, as shown in FIG.
00 and a rectangular rear portion 102. Pivot mounting bosses 92 and 94 provide an improved bearing surface between blade members 12 and 14 while maintaining alignment of cutting surfaces 70 and 72.

In cutting shears 10, the offset of cutting surfaces 70 and 72 is determined by the position of pivot mounting bosses 92 and 94. As a result, cutting scissors 10
The regrinding is accomplished by grinding both the cut surfaces 70 and 72 and each pivot mounting boss 92 and 94. It will be appreciated that if equal thicknesses of material are ground from the upper cut surface 70 and the pivot mounting boss 92, no change will occur in the offset of the upper cut surface 70. Similarly, if equal thicknesses of material are ground from the lower cut surface 72 and the pivot mounting boss 94, no change will occur in the offset of the lower cut surface. In this manner, either or both of the blade members 12 and 14 can be sharpened, if desired, without creating a lateral space between the cutting surfaces 70 and 72.

Regrinding of each blade member is even simpler since there is no need to regrind the curved surfaces. Upper and lower cut surfaces 70 and 72 are ground in planes substantially parallel to each boss 92 and 94. Pivot mounting bosses 92 and 94 are first ground to provide reference surfaces for grinding of cutting surfaces 70 and 72. Recessed portions 78 and 8 of each blade member 12 and 14
0 ensures that no other surfaces need to be ground during regrinding. The height of the pivot mounting bosses 92 and 94 that protrude from the adjacent handles 62 and 64 is
It is known that sufficient grinding ability can be obtained if the diameter is 1/32 of 2.54 cm. The articulated engagement of blade members 12 and 14 with handles 18 and 20 causes cutting surfaces 70 and 72 to
6, 40 and 42 can be placed in the grinding fixture by simply removing the pivot bolt 16 while remaining fixed in place.

The inventor has discovered that if the upper and lower cut surfaces 70 and 72 are not exactly parallel to the pivot mounting bosses 92 and 94, but are angled slightly so that they gradually interfere with the closing of the blade member, the sheet-like material It was found that the cutting of the cut object was improved. Although similar effects can be achieved with different amounts of interference, it is preferred that there be an angle of about 15 minutes on each of the cutting surfaces 70 and 72 for a total interference of approximately 1/2 degree. This interference ensures that the blades are tightly aligned during the latter half of the cutting process and that the shearing action is achieved. Desired angles and offsets can be conveniently and economically formed when the blade members 12 and 14 are initially ground or later reground for resharpening.

Grinding of the pivot mounting bosses 92 and 94 is performed by grinding the adjacent handle portions 62 and 6 of the upper and lower blade members 12 and 14.
This is merely illustrative of the inventive concept of removing material from 6 and resharpening the cut surfaces 70 and 72.

Milling or other cutting means may also be used in place of grinding if such cutting means are not hampered by the hardness of the blade members 12 and 14.

Another feature is a locking means that can be manually locked to prevent the cutting shears 10 from opening from the closed position shown in FIG. The pivot bolt 40 has a shoulder portion formed between the handle portion and the head portion. The locking strap 104 is attached to the upper and lower handles 18 and 2.
It is pivotally mounted on pivot bolts 42 on the outside of laterally spaced sides 44 and 46 of 0. The free end of the locking strap 104 is notched in the side to form a hook surface 106. The locking strap 104 is
1, which is capable of operating the cutting shears 10.
From this position, the scissors 10 are manually moved between the pivot bolt 40 and the handle pivot 26 to a second position shown in FIG. 2 which locks the cutting shears 10 in the closed position. In the second position, the hook surface 106 of the free end of the locking strap 104 is rotated into engagement with the shoulder of the pivot bolt 40 such that the locking strap 104 is held in compression by the omega spring 50. The locking strap 104 can conveniently be released or engaged by the operator's thumb, allowing one-handed operation.

Another important feature of the cutting shears 10 is that the handle 66 of the lower cutting member 14 is aligned with the path of the cut sheet material 22 passing over the front portion 86 of the lower cutting member 14. A triangular notch or recess 110 is provided in the. Recess 11
0 allows the cutting shears 10 to perform right-handed as well as left-handed cuts. The shape of the cutting shears 10 shown in the preferred embodiment is particularly suited for straight and left-curving cuts. However, due to the recess 110,
Right-turning cuts with diameters greater than 10.16 cm are also possible, thereby eliminating the need for separate cutting shears specifically adapted for right-turning cuts. Similar cutting shears could be provided with a plane symmetrical construction particularly suited for straight and right-handed cuts, but also capable of making left-handed cuts of 4 inches in diameter.

Yet another important feature of the cutting shears 10 is that the handles 18 and 20 are particularly convenient and allow the application of force through the full range of travel of the cutting blades 12 and 14. .
Unlike conventional offset shears, handle pivot bolt 26 is relatively close to grips 32 and 34. As a result, when the cutting shears 10 are in the open position shown in FIG. 1, the angle formed between the handles 32 and 34 is greater than that of conventional scissors. In the open position, the grips 32 and 3
The front part of 4 has an ear part 36 to maximize leverage.
and 38 the operator's hand is placed on the handle 18
and 20 minutes apart. The lower handle 20 is configured such that the open position of the lower grip 34 does not interfere with the workbench on which the sheet material 22 to be cut is placed for cutting. As the upper and lower blade members 12 and 14 move toward the closed position shown in FIG.
The more rearward portions of 2 and 34 ideally separate progressively to provide maximum leverage. Additionally, blade members 12 and 14 and handles 18 and 20 constitute a four-bar linkage. This linkage provides amplification in transmitting manually applied forces to the cutting surfaces 70 and 72, reducing operator effort and fatigue.

A variety of materials can be used to form the cutting member and handle depending on the sheet material to be cut. In the preferred embodiment shown, the cutting blade is forged from alloy tool steel and ground to the shape shown.
Such a structure provides sufficient strength to allow the steel sheet to be cut by the cutting blade. However, other materials and cheaper forming methods may be used, especially when cutting less strong sheet materials. Handles 18 and 20 can be conveniently and economically formed from mild steel by various stamping operations. The locking strap 104 can also be conveniently and economically formed from sheet steel.

Referring to FIGS. 10-19, an improved universal offset scissor having an improved wire cutter is shown at 10'. Cutting shears 10' have upper and lower blade members designated 12' and 14', respectively. The upper and lower blade members 12' and 14' are each designated by the reference numeral 1.
Upper and lower handles, indicated at 8' and 20', allow rotation about the main pivot bolt 16'. The opening position shown in Figure 10 and the first
By moving the blade members 12' and 14' between the closed position shown in FIG. ' or a wire-shaped object to be cut 24' is cut.

Handles 18' and 20' are rotatable about a handle pivot bolt 26' located intermediate between the ends of handles 18' and 20'. The rear portions 28' and 30' of each handle 18' and 20' have upper and lower grips 3, respectively.
2' and 34'. Preferably,
Handles 32' and 34' are dipped or molded to have outwardly projecting ear portions 36' and 38', respectively, to prevent the operator's hands from slipping forward during use of cutting shears 10'. It is formed.

Handles 18' and 20' extend forwardly and away from each other from handle pivot bolt 26' to pivotally mount blade members 12' and 14' with pivot bolts 40' and 42'. There is. In the open position shown in FIG. 10, an acute angle is preferably formed between the imaginary line connecting pivot bolts 26' and 40' and the imaginary line connecting pivot bolts 26' and 42'. Such an acute angle is on the order of about 70 degrees in both embodiments of the invention. However, in the closed position, the angle between the two imaginary lines of equal length is preferably increased from about 114 degrees to 119 degrees, resulting in a shallower toggle linkage and offset scissors in the closed position. A stronger grip results as the time toggle axis points approach a straight line. Furthermore, by bringing the pivot bolts 40' and 42' closer together and closer to a straight line than in both embodiments, the handle pivot bolt 26' is located at the point of maximum force on the toggle mechanism. This will allow you to unleash your maximum potential. Thus, in this embodiment, the handle pivot bolt 26', the pivot bolts 40' and 4
2' is approximately 0.635 cm, which is shorter than the embodiment shown in FIGS. Therefore, it is possible to provide improved offset scissors having the following characteristics. In addition, in this embodiment, the line connecting the pivot bolts 40' and 42' of the toggle mechanism crosses the center of the triangle in the open position, and the two acute angles with the pivot bolts 40' and 42' as vertices are equal. , each acute angle is a pivot bolt 4
An angle of about 30 degrees to about 33 degrees is formed with yet another imaginary line connecting 0' and 42'. Preferably,
The handles 18' and 20' have a U-shape formed by laterally spaced sides 44' and 46' joined by a web portion 48', as shown in FIG.
It has a letter-shaped cross section. Omega spring 50', held in place by handle pivot bolt 26', engages web portions 48' of handles 18' and 20' to bias cutting shears 10' to the open position.
Other biasing means can also be used as long as they have similar effects. Although the sleeve 51' is not essential to the operation of the cutting shears 10', the inventor has found that the sleeve 51' substantially extends the cycle life of the omega spring 50'. ing.

In the open position, the upper blade member 12'
As shown, it extends upwardly and rearwardly from the main pivot bolt 16' to a pivotable mounting on the pivot bolt 40'. Lower blade member 14' extends rearwardly from main pivot bolt 16' to a pivotable mounting on pivot bolt 42'. When handles 18' and 20' are closed, pivot bolts 40' and 4
2' rotates about handle pivot bolt 26', thereby spreading rear portions 54' and 56' of blade members 12' and 14'. As shown in FIG. 12, the rear portions 54' and 56'
It is thick enough to be sealingly received by sides 44' and 46' of 8' and 20', thereby holding upper and lower cutting blades 12' and 14' in alignment. Adjustment of the play between sides 44' and 46' and rear portions 54' and 56' is provided by adjustment nuts 58' on pivot bolts 40' and 42'.

The main pivot bolt 16' is attached to the handle 6 of the upper blade member 12'.
2' and a sliding fit into a hole 64' in the handle 66' of the lower blade member 14'. Lock nut 68' is locked against handle 62' to maintain the adjusted length of main pivot bolt 16'. Cutting surfaces 70' and 7 of cutting blades 12' and 14'
2' lies in a substantially parallel but laterally offset plane with the adjacent handles 62 and 66' of each blade member, as shown in FIG. The offset allows the cut portion of the sheet-like material to be cut 22' to pass through the side of the handle 66', but more importantly, the
It is possible to cut opposing circles of 6.35 cm. This configuration allows sheet metal to be cut with a single tool such as an extended offset blade capable of cutting straight lines as well as sharp curves in either left or right directions.

In this embodiment, the cutting surfaces 70' and 72' are similarly curved at the sides with the same radius, as shown in FIGS. 13 and 16, so as to present a convex cutting surface with respect to the workpiece. has been done. Also, the first
As with the embodiment shown in FIGS. 9-9, the front portions 84' and 86' of each blade member 12' and 14' extend laterally generally perpendicular to the handles 62' and 66'.

Preferably, the blade members 12' and 14' are aligned along surfaces 78' and 80', respectively, so that the upper and lower cutting surfaces 70' and 72' have uniform widths on the sides while resharpening the blade members, as described below. It is ground into a concave shape. At the rear of the lower cutting surface 72',
Relief 82' is provided to facilitate grinding of cutting surface 72' and to ensure smooth sliding engagement of cutting blades 70' and 72' during cutting. Blade member 1
The front parts 84' and 86' of 2' and 14' are the 15th
It curves inward to form a convex surface as shown in FIG. This shape of the front portions 84' and 86' provides sufficient strength to the cutting blades 70' and 72' while still allowing the cutting shears to be attached to the cutting shears for cutting where space is at a premium. 10' can be operated.

The wire to be cut 24' is cut by the upper blade member 1.
This is accomplished by engagement of a ferrule 88' formed on the lower blade member 14' with a wedge 90' formed on the lower blade member 14'. Kanato part 88' especially rust part 9
The position 0' means that the cutting scissors 1
0' is such as to form a stop that limits rotation of the blade member when in the closed position as shown in FIG. The wedge portion 90 is the cutting scissors 1
When 0' moves from the open position shown in FIG. 10 to the closed position shown in FIG. 11, it acts as a chisel for cutting wire, rod, small bar material, etc. placed on the lug 88'. The opposing cutting blades cut the wire using scissor cutting. The scissor cut may also be any other cutting means, such as a shear cut, which preferably does not require a separate stop. For shear cutting surfaces in the form of scissor-like cutting blades between portions of opposing blade members, the scissors of the present invention also include a pair of abutments between the handle and blades to limit rotation of the blade members. Members 89 and 91 (stops) are required (first
(best shown in phantom lines in Figures 0 and 11). Such stops are 19a and 1
They are also necessary in the embodiment shown in FIG. 9b.
In these embodiments, the shear type wire cutter has been replaced with a scissor type wire cutter. 19th
When using the shear type cutter shown in Figure a, the corner portion 88' is only ground to pass the cutting blade or chisel 90', and the chisel 90' passes the opposing shear blade 93'. The movement (shown in phantom) cuts the wire (also shown in phantom). In Figure 19b, the sharp cutting edge of shear blade or chisel 90' is disposed at an opposite angle to that of chisel 90' shown in Figure 19a, so that the opposing shear blade 93' offset to the outside.

For either scissor-type cutters or shear-type cutters, no relief is required at the base of the cutter blade, since the chisel or knife blades are all sharpened by grinding over the entire surface of the cutter member. In the improved scissors of the present invention, the cutter is formed by grinding an angled or diagonal blade from a straight edge, so that a single grinding pulse is required to form the cutter in either type. Only . Thus, such knife blades or shear blades may have substantially smaller angles and therefore can be significantly sharper than conventional blunt V-shaped angled scissors.
For example, while an angle of about 70 degrees is provided for the chisel in FIGS.
Angles of 40 degrees to about 60 degrees are satisfactory.
Compared to previous scissors and cutters, the small angle cutter of the present invention appears to produce significantly less friction when cutting. In such cases, the blade member is essentially made of stronger steel to maintain a sharp cutting edge. Preferably, an angle of about 50 degrees has been found to be suitable for those practicing the invention. At the 70 degree obtuse angle of the V-shaped pinch cutters in Figures 1 to 9,
It should be appreciated that a wider wedge-shaped chisel would have significantly more frictional resistance and therefore would require more force to pinch or cut the wire.

With the full-width cutter of the present invention, there is no relief at all at the base of the cutter, so even extremely small wire can be easily cut. In this way, whether the scissor type or the shear type, small wires can be cut easily without the risk of them getting caught in the recesses in the base of the katatsu or kanatoko and being cut uncut or only incompletely. The wire can be placed anywhere along the cutting blade or ferrule.

In situations such as the above, the wire may be re-cut at a different point from where it has already been cut, or to complete an incomplete cut at the same point, or to re-engage the wire. does not require the aid of any special process for precise alignment; all you need to do is carefully place the wire in the center of the stub.

It is an important feature of the present invention that cutting surfaces 70' and 72' can be reground to refurbish worn or damaged cutting surfaces. Referring to FIG. 12, grinding either the upper cut surface 70' or the lower cut surface 72' creates a lateral space between the cut surfaces 70' and 72' to cut the sheet of material to be traversed 22'. It is generally expected that this will not be possible. Cut surface 7 for handle 62'
The 0' deviation increases with such grinding.
Therefore, once commercially available offset scissors become dull or damaged, they cannot be conveniently resharpened.

The re-grinding of the cutting scissors 10' of the present invention is performed by
This is facilitated by pivot mounting bosses 92' and 94' on adjacent surfaces of 2' and 66', respectively. Pivot mounting bosses 92' and 94' are flat projections that project above the surfaces of handles 62' and 66' perpendicular to main pivot bolt 16'. The pivot mounting boss 92' in the preferred embodiment has a semicircular forward section 96' concentric with the main pivot bolt 16' and a generally slender rectangular upper section 97, as shown in FIG. It can be something. The pivot mounting boss 94' has a semicircular front portion 10 concentric with the main pivot bolt 16', as shown in FIG.
0' and a generally upwardly extending portion 101.

Pivot mounting bosses 92 and 94 provide an improved bearing surface between blade members 12' and 14' while maintaining alignment of cutting surfaces 70' and 72'. The upper portions 97 and 101 respectively reinforce the strength of the chisel itself as well as of the lug portion 88'.

In cutting shears 10', the offset of cutting surfaces 70' and 72' is determined by the location of pivot mounting bosses 92' and 94'. As a result, regrinding of the cutting shears 10' requires cutting surfaces 70' and 7
2' and each pivot mounting boss 92' and 94' (and their upper portions 97 and 101). It will be appreciated that if equal thicknesses of material are ground from the upper cut surface 70' and the pivot mounting boss 92', no change will occur in the offset of the upper cut surface 70'. Similarly, if equal thicknesses of material are ground from the lower cut surface 72' and the pivot mounting boss 94', no change will occur in the offset of the lower cut surface. In this way, if necessary, without creating a lateral space between the cutting surfaces 70' and 72',
Either or both of the blade members 12' and 14' can be sharpened.

Since there is no need to re-grind the curved surfaces, re-grinding each blade member is very easy. Upper and lower cut surfaces 7
0' and 72' are ground in a plane substantially parallel to each boss 92' and 94'. Cut surface 7
Pivot mounting bosses 92' and 94' are ground first to provide reference surfaces for grinding 0' and 72'. The recessed grinding portions 78' and 80' of each blade member 12' and 14' eliminate the need to grind other surfaces during regrinding. It has been found that sufficient grinding capacity is provided if the height of the pivot mounting bosses 92' and 94' projecting from adjacent handles 62' and 64' is 1/32 of an inch. The articulation of the blade members 12' and 14' to the handles 18' and 20' allows the cutting surfaces 70' and 72' to be removed from the main pivot bolt 16 while the pivot bolts 26', 40' and 42' are fixed in place. It can be placed on the grinding fixture by simply removing the '.

As mentioned above, the upper and lower cut surfaces 70' and 7
2' is not exactly parallel to the pivot mounting bosses 92' and 94', but is slightly angled so as to gradually interfere with the closing of the blade member, improving the cutting of the sheet material to be cut. . Although similar effects can be achieved with various amounts of interference, it is preferred that each of the cut surfaces 70' and 72' have an angle of approximately 15 minutes to provide a total interference of approximately 1/2 degree. This interference ensures that the blades are tightly aligned during the latter part of the cutting process and that the shearing action is performed reliably. When the blade members 12' and 14' are initially ground or later reground for resharpening,
Desired angles and offsets can be formed conveniently and economically.

A suitable locking means for manually locking the cutting shears 10' from opening from the closed position is a first locking means.
This is shown in Figure 1. The pivot bolt 40' has a shoulder portion formed between the handle portion and the head portion.
Locking straps 104' are attached to laterally spaced sides 44' and 4 of upper and lower handles 18' and 20'.
It is pivotably mounted on the pivot bolt 42' on the outside of 6'. Locking strap 104'
The free end of has a notch formed in the side to form a hook surface 106'. The locking strap 104' moves from a first position shown in FIG. 10, in which the cutting shears 10' are operable, to a second position, shown in FIG. 11, in which the cutting shears 10' are locked in the closed position.
It is manually moved between the pivot bolt 40' and the handle pivot 26'. In the second position, the locking strap 1
The hook surface 106' at the free end of 04' is rotated so that the pivot bolt 40' is held in compression by the omega spring 50'.
engages with the shoulder of the The locking strap 104' is
Conveniently, it can be released or engaged by the operator's thumb, allowing one-handed operation.

The cutting surfaces 70' and 72' of the blade members 12' and 14' are significantly offset from the pivot mounting boss to provide a versatile offset scissor capable of cutting opposing small circles of approximately 5.08 cm to 6.35 cm diameter. However, the front part 8 of the lower blade member 14
Lower blade member 14' is aligned with the path of cut sheet material 22' passing over 6'.
A triangular notch or recess 11 in the handle 66' of the
0' is provided. The recess 110' allows the cutting shears 10' to make right-handed as well as left-handed cuts. Both the shapes of the cutting shears are particularly suitable for straight and left-curving cuts. however,
The improved version shown in FIGS. 10 to 19 allows cuts to be made equally well in cuts that curve to the right. That is, when there is a small circle or a sharp curve in the opposite direction from the standard direction of the tool. Thus, the embodiment of FIGS. 10-19 is also capable of making right-turning cuts approximately 2.0 inches to 2.5 inches in diameter. There is thus no need for separate cutting shears specifically adapted for right-turning cutting.

Still other important features of the cutting shears 10' are:
Handles 18' and 20' are particularly convenient in that they allow force to be applied through the full range of travel of cutting blades 12' and 14'. Unlike conventional offset shears, handle pivot bolt 26' is relatively close to handles 32' and 34'. Also, compared to FIGS. 1-9, handle pivot bolt 26' is approximately 0.635 cm closer to pivot bolts 40' and 42'. As a result, when the cutting shears 10' are in the open position shown in FIG. Therefore, the angle is larger than that of conventional scissors. Also, the angle with the pivot bolt 26' at the apex is larger than that in FIGS. 1 to 9. Because of the placement of pivot bolts 40' and 42' in close proximity to pivot bolt 26', the angle between the virtual toggle links between pivot bolt 26' and each of pivot bolts 40' and 42' is closed. Preferably from about 115 degrees to about 120 degrees, more preferably about 117 degrees for the scissors in position. With this configuration, 3
A stronger scissor is achieved because the center point of the member toggle linkage is closer to dead center (maximum force) where the three pivot points form a straight line.

In the open position, the front portions of handles 32 and 34
To maximize leverage, ear portions 36' and 3
The operator's hand placed at 8' is spaced apart such that the thumb and little finger rest on the handles 18' and 20'.
The lower handle 20' is configured such that the open position of the lower grip 34' does not interfere with the workbench on which the sheet material 22' is placed for cutting. As the upper and lower blade members 12' and 14' move towards the closed position shown in FIG. do.

Of course, various modifications and improvements to the preferred embodiment described above will occur to those skilled in the art. For example, rivets or other pivoting means could be used in place of the four bolts without affecting the operation of the cutting shears. It is therefore intended that the above detailed description be regarded as illustrative rather than restrictive, and it is the following claims, including equivalents, that define the scope of the invention.

[Brief explanation of drawings]

1 is a partially cut-away side view of the offset scissors of the present invention in an open position; FIG. 2 is a partially cut-away side view of the offset scissors of FIG. 1 in a closed or cutting position; FIG. 4 is a side view of the upper cutting blade of the offset scissors shown in FIGS. 1 to 3; Figure 5 is a cross-sectional view of the upper cutting blade of the offset scissors shown in Figures 1 to 3, taken along line 5--5 in Figure 4, and Figure 6 is a cross-sectional view of the upper cutting blade of the offset scissors shown in Figures 1 to 3. FIG. 7 is a side view of the lower cutting blade of the offset scissors shown in FIGS. 1 to 3; FIG. 8 is a cross-sectional view taken along line 6--6 in FIG. A sectional view of the lower cutting blade of the offset scissors shown in FIGS. 1 to 3 taken along line 8-8; FIG. 10 is a partially cut-away side view of a more preferred embodiment of the offset scissors of the present invention in an open position; FIG. 11 is a cross-sectional view of the offset scissors of FIG. 12 is a cross-sectional view of the offset scissors of FIGS. 10 and 11 taken along line 12--12 of FIG. 11; FIG. 13 is a cross-sectional view of the offset scissors of FIGS.
The figure is a side view of the upper cutting blade of the offset scissors shown in Figures 10 to 12, and Figure 14 is a side view of the upper cutting blade of the offset scissors shown in Figures 10 to 12, taken along line 14-14 in Figure 13. 15 is a cross-sectional view of the upper cutting blade of the offset scissors shown in FIGS. 10-12, taken along line 15--15 in FIG.
17 is a side view of the lower cutting blade of the offset scissors shown in FIGS. 10 to 12, and FIG.
Sectional view taken along line 17-17 in Figure 18
18-18 in FIG. 16 of the lower cutting blade of the offset scissors shown in FIGS. 10 to 12.
19a and 19b are partial top views of opposing shear blades of a typical shear cutter that can be used in place of a scissor cutter if desired. 10,10'...cutting scissors, 12,12'...
Upper blade member, 14, 14'...Lower blade member, 16,
16'... Main pivot bolt, 18, 18'... Upper handle, 20, 20'... Lower handle, 22,
22'... Sheet-shaped object to be cut, 24, 24'... Wire, 26, 26'... Handle pivot bolt, 40,
40', 42, 42'... Pivot bolt, 70, 7
0', 72, 72'...cut surface, 88, 88'...
Kanatoko, 90,90'...tagane, 92,9
2', 94, 94'... Pivot mounting boss.

Claims (1)

[Scope of Claims] 1. Flat first and second pivot mounting bosses;
and upper and lower blade members respectively having first and second cut surfaces offset with respect to the surface of the second pivot mounting boss, and a pivot means for rotatably coupling the upper and lower blade members, opposing handle means for pivoting the upper and lower blade members about the pivot means such that the first and second cutting surfaces move between an open position and a closed position for cutting the sheet material therebetween; , the first
and pivot means for rotating about an axis perpendicular to the second pivot mounting boss. The first part forms the diagonal chisel blade of the katsuta.
including an upwardly extending portion of the pivot mounting boss, and further including an upwardly extending portion on the lower blade member acting as a wire cutting surface opposite the chisel blade, for resharpening the offset scissors. In order to make it easier, the first and second pivot mounting bosses are made to protrude in opposite directions until the blade member comes into contact with them, and the facing surfaces are formed flat, and the pivot mounting bosses are used as a reference surface to attach the pivot shaft. Material is removed from both the pivot mounting boss and the cutting surface as well as the chisel blade to achieve resharpening of the cutting surface while maintaining the offset between the mounting boss and the cutting surface; The entire surface of the facing surface of the wire cutter is a chisel blade with no relief, and the relief prevents the wire from getting caught and unable to move during cutting, and the offset scissors have a minimum diameter of 5.08 mm. All-purpose offset scissors that can make small opposing circular cuts from 1/2 inch to 6.35 centimeters. 2 The upwardly extending portion of the first pivot mounting boss is a ferrule, the wire cutter is a scissor-type cutter, and the ferrule and chisel are simultaneously attached to the upper and lower blade members. Universal offset scissors according to claim 1, which act as a stop for movement of the first and second cutting surfaces. 3. The universal offset scissors of claim 2, wherein said chisel is a knife-like blade angled at about 40 degrees to about 60 degrees. 4. Universal offset scissors according to claim 3, wherein the chisel is a knife-like blade angled at about 50 degrees. 5 said opposed handle means having a pivot joint therebetween and rotatable coupling to said upper and lower blade members, so that a three-point toggle linkage is formed between said opposed handle means and said blade members; and the angle formed by each of the pivot joints and the rotatable couplings when the blade member is in the closed position is about 115 degrees to about 120 degrees, and the angle between the rotatable couplings and the pivot joints is about 115 degrees to about 120 degrees; 5. The universal offset scissors according to claim 4, wherein a large force is generated in the offset scissors as the angle approaches the dead center where the force is maximum. 6. The universal offset scissors of claim 5, wherein the pivot joint angle is about 117 degrees. 7. A claim in which the chisel of the upwardly extending portion of the first pivot mounting boss forms an opposing shearing blade so as to pass past the opposing shearing blade, whereby the wire cutter is a shear type cutter. range 1
All-purpose offset scissors listed in section. 8. According to claim 7, a pair of abutment means are provided on said opposed handle means for providing a stop to movement of said first and second blade sections of said upper and lower blade members. All-purpose offset scissors listed. 9. The universal offset scissors of claim 8, wherein said shearing blades are knife-like blades angled from about 40 degrees to about 60 degrees. 10. The universal offset scissors of claim 9, wherein the shear blades are knife-like blades angled at about 50 degrees. 11 said opposed handle means having a pivot joint therebetween and rotatable coupling to said upper and lower blade members, so that a three-point toggle linkage is formed between said opposed handle means and said blade members; and the pivot joint angle formed by each of the pivot joints and the rotatable connections when the blade member is in the closed position is about 115 degrees to about 120 degrees, and the angle between the rotatable connections is about 115 degrees to about 120 degrees; 5. A universal offset scissor as claimed in claim 4, in which said pivot joint approaching dead center creates a large force on the offset scissors. 12. The universal offset scissors of claim 11, wherein the angle of the pivot joint is about 117 degrees.