The present invention relates to fully insulated combination pliers capable of cutting and stripping wires without damaging the wire filaments.

More particularly, the present invention relates to a fully insulated combination Pliers for safety while in use at high voltage electrical power transfer cables, where voltage reached to maximum of 8000 volts (or 8kV).

BACKGROUND AND PRIOR ART OF THE INVENTION
High voltage power transfer cables such as used to transfer over a million volts of electrical power, are generally configured with the high power conductor wires for carrying the electrical power located at the center of the cable, molded within a first layer of insulation. Immediately around the circumference of the exterior of the first layer of insulation, a plurality of neutral conductor wires radially propagating parallel along the length of the cable, the neutral conductor wires being embedded within an outer insulating jacket.

A linesman who is skilled in repairing, and connecting high voltage power cables is repetitively required to prepare a cut cable for conductor connection in compromised locations, such as in a trench or vault. High voltage power cables are stiff, large in circumference, and difficult to bend. The conventional tool for this procedure is a so called “linesman pliers”, which incorporate a solid joint with diagonal cutting blades and crimping surfaces, as well as jaws that are used to grip and hold the stripped wires.

Conventional pliers with only handles insulated can’t be used beyond 2800 Volts or so. Due to high voltage insulated wire 8 kV thick insulating layer, common electrical wire stripper with stripping of its insulation can not be an outer layer, generally employed is to stripping the electric knife, the operation is very troublesome, low efficiency.

Reference may be taken from U.S. Pat. 8418519 which disclose a hand tool comprising handles and jaws, where the jaws are operated by the handles, and where an anti-slip device is arranged on the outer side of the distal end of a tool handle. The tool handle has a hard surface with low friction enabling the users fingers to slide on the surface of the handle when squeezing the handles together, and the anti-slip device is arranged to be supported against a support surface in order for the user to be able to press the tool handles together in a controlled manner using a force (F) in excess of hand force. The primary object of this invention is to provide an improved hand tool in order to be able to use force in excess of hand force to in a controlled manner press together the handles of a hand tool having at least one handle having a hard surface with low friction, however the scope and objective of the present invention is far different from it.

Another reference may be taken from CN Utility Model No. CN2701135 which relates to a high-voltage insulated conductor stripper which is especially suitable for the peeling of the high-voltage insulation series conductor of 8 kV. The utility model comprises a left pliers body and a right pliers body which are hinged by a pin shaft. An idler wheel type radial cutter and a cutter blade type axial direction cutter are arranged on the inner and outer side of the hinging point of the left and right plier body respectively. When the utility model is used, the idler wheel type radical direction cutter radially cuts the conductor insulating layer, and the idler wheel cutter rolls in circumferential direction with the edge of the plier to cut the radial fault of the conductor insulating layer. And then, the cutter blade type axial direction cutter axially cuts the radical direction disconnected insulating layer into two parts. Thus, the stripping mission of the insulated conductor is finished. The utility model has the advantages of simple structure, easy manufacture, convenient use and carrying, strong use function and good peeling quality. Besides, the utility model has the advantages that the cutting manner of the utility model is more labor-saving than other cutting manners, the utility model can not only cut and peel the insulating layer on the end of the conductor, but can also cut and peel the insulating layer in the intermediate section, and the core of conductor is not easy to scratch, however the particular invention focus to simplify the structure of pliers and no way indicate about the insulation on the pliers so that it would be capable to cut and peel high voltage transmission power wires.

In order to reduce the chance of injury, particularly electrical shock, where a tool may make contact with an energized source, tools have historically been insulated upon their handle portion. Reference may be taken from U.S. Pat. No. 1902438 which discloses a tool or the like, coated with electric insulation material having the dielectric characteristic of cellulose acetate, and a label embedded in said material, covered over by the material and visible through the latter, however this kind of tools may work on high voltage electrical equipment but not beyond 2800 volts power, however in the present invention , injection molding die has been developed for single piece injection molding of plier with thick layer (up to 4 mm) of virgin grade cellulose acetate material in order to make capable the pliers to work with high voltage electrical power of up to 8 kV.

None of the prior art tools appear to provide a simple and reliable insulation on pliers to make it fully insulated with capacity to work with high voltage electrical power up to 8 kV.

Though above inventions are for tools for cutting and snipping of wires in the high voltage transmission, however, these are limited by its structure or poor insulation only, there is no single piece injection molding die being presently used as in present invention which makes present pliers fully insulated with capable to work with high voltage electrical power up to 8 kV. The primary object of this invention is to provide an improved hand tools in order to be able to use force in excess of hand force to in a controlled manner press together the handles of a hand tool having a hard surface with low friction. However, the scope and objective of the present invention is far different from it. It is fully insulated combination pliers with comfortable grip with anti-slip etching surface on sleeves for easy and firm handling. It contains one piece thick insulated layer upto 4 mm of virgin quality cellulose acetate material.

OBJECTS OF THE INVENTION
In view of the drawbacks and limitations of the prior art, it is an object of the present invention to provide a fully insulated combination pliers.

Another object of the present invention is to provide fully insulated combination pliers for safety while in use at high voltage electrical power transfer cables up to 8 kV.

Further, another object of the present invention is to provide fully insulated combination pliers with comfortable grip with anti-slip etching surface on sleeves for easy & firm handling.

Yet, another object of the invention is to provide a fully insulated combination plier with one piece thick insulated layer up to 4 mm of virgin quality cellulose acetate material.

SUMMARY OF THE INVENTION
Present invention provides a fully insulated combination pliers and a process of insulating the same. The said pliers are capable for safety while in use at high voltage up to 8 kV electrical power transfer cables, where the said pliers have rigid members fully being insulated comprises a plurality of substantially flat lamination, including at least one inner insulation secured between oppositely-disposed outer insulation; wherein the said insulation is comprised of thick layer of virgin quality cellulose acetate thickness up to 4 mm. The Process entailes injection moulding wherein a single piece combination pliers made of chrome-vanadium steel is placed inside the die cavity and injection moulding process results in covering the whole body and legs of pliers with thick layer of virgin quality cellulose acetate material.
BRIEF DESCRIPTION OF THE DRAWINGS:
The disclosure will provide details in the following description of preferred embodiments with reference to the following drawings, wherein:

FIG. 1 depict a perspective view of plier’s rigid members each having a handle portion, joint cutter, jaws and pliers tip, and the members being joined in a scissors-like arrangement.

FIG. 2 depicts rigid members joined through operation of riveting with alloy steel rivet on orbital riveting machine

FIG.3 is an exploded perspective view of the insulating layers.

The above summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, certain embodiments are shown in the drawings. It should be understood, however, that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings.

DESCRIPTION OF THE INVENTION
In the following description, for the purposes of explanation, various specific details are provided in order to provide understanding of the disclosed invention. It will be apparent, however, that the disclosed embodiments may be practiced without these specific details. Several features described hereafter can each be used independently of one another or with any combination of other features. However, any individual feature may not address any of the problems discussed above or might address only some of the problems discussed above in the background section.

Accordingly, the present invention provides fully insulated combination pliers for safety while in use at high voltage electrical power transfer cables, comprising:
first and second rigid members (1,1’), each having a handle portion (2, 2’), joint cutter (3,3’), jaws (4,4’) and pliers tip (5,5’), the members (1,1’) being joined in a scissors-like arrangement whereby the pliers tip (5,5’) are caused to move toward each other in response to the handle portions (2, 2’), being moved toward each other; wherein first and second rigid members (1,1’), have gripping surface (6,6’), pipe grips (7,7’), and cutter (8,8’), characterized in that the first and second rigid members (1,1’) fully being of insulated comprises a plurality of substantially flat lamination, including at least one inner insulation secured between oppositely-disposed outer insulation; wherein the said insulation is comprises alloy steel as a first layer , injection molding die as a second layer, and cellulose acetate as a third layer, wherein the said pliers can pass through high voltage up to 8KV electrical power transfer cables.

In an embodiment of the present invention, the handle portion (2, 2’) of the rigid member (1,1’), has a comfortable grip (9,9’) for easy handling.

In another embodiment of the present invention, the alloy steel is chrome-vanadium steel.

Further, in an embodiment of the present invention, the injection molding die is preparedfor single piece/injection molding of pliers with thick layer (upto 4 mm) of virgin grade cellulose acetate in order to make the pliers capable to work with high voltage electrical power of upto 8 KV.

In yet another embodiment of the present invention, both the rigid members are connected with the operation of riveting with allow steel rivet on orbital riveting machine.

The present invention also provides a process for insulation of combination pliers, wherein the said process comprises the steps of:
a) alloy steel forging as a first layer of insulation on the said pliers and machining it;
b) inserting the forged alloy steel pliers of step (a) in injection molding die at the temperature 65 degree to 75 degree as a second layer of insulation;
c) injecting cellulose acetate as third layer of insulation by injection molding machine in order to get the fully insulated combination pliers.

In an embodiment of the present invention, the alloy steel is steel containing additional alloying elements other than carbon selected from the group consisting of Ni, Cr, Mo etc.

In another embodiment of the present invention, the alloy steel preferably used is chrome-vanadium steel.

Further, in an embodiment of the present invention, the injection molding die is prepared for single piece/injection molding of pliers with thick layer (upto 4 mm) of virgin grade cellulose acetate in order to make the pliers capable to work with high voltage electrical power of upto 8 KV.

In yet another embodiment of the present invention, the said pliers is capable to pass through high voltage up to 8 kV electrical power transfer cables by using injection molding die as a second layer of insulation
.
In yet another embodiment of the present invention, the insulation thickness is in the range of 2mm to 4mm.

In yet another embodiment of the present invention, the wherein the insulation thickness is preferably up to 4 mm.

The ensuing description provides the device only, and is not intended to limit the scope, applicability, or configuration of the claims. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing the embodiments. It is being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the appended claims.

Reference is now made to Fig-1 which illustrates fully insulated combination pliers. The pliers have first and second rigid members (1,1’), which is fully insulated and each member (1,1’) having a handle portion (2, 2’), joint cutter (3,3’), jaws (4,4’) and pliers tip (5,5’). The rigid members are joined in a scissors-like arrangement through operation of riveting with alloy steel rivet on orbital riveting machine as can be seen in Fig -2 whereby the pliers tip (5,5’) are caused to move toward each other in response to the handle portions (2, 2’). The members (1,1’) also have gripping surface (6,6’), pipe grips (7,7’), and cutter (8,8’). The griping surface (6,6’) is provided for easily handling.

In Fig-3 the exploded perspective view of the insulating layers of fully insulation combination pliers are shown. The insulation is performed by plurality of substantially flat lamination, including at least one inner insulation secured between oppositely-disposed outer insulation. The first layer of insulation on pliers is forged by alloy steel preferably cromium-venedium steel, then it is machined and insert in a injection molding die and cover it as a second layer followed by injecting the cellulose acetate as a third layer. Machining comprises of operation of drilling, Seat Milling, Die Broaching, Straightening, Back Cutter, Teeth Milling, Final Seat Milling, Edge Cutting, Riveting, Final Back Cutting, Lapping side joint Cutting and Reaming etc. Detailed process of machining is shown in Figure-4.

Bu using such insulation of three layers on combination pliers, it can pass through high voltage up to 8 kV electrical power transfer cables. The dielectric strength test was performed with metal part and insulation wrapped with metal/aluminum foil until failure upto 10 LV for 60 seconds. As a result no flash over or no breakdown occurred during the test upto 8100 V. A copy of said test report is shown below:

LIST OF REFERENCE NUMERALS:

Rigid members (1,1’)
Handle portion (2, 2’)
Joint cutter (3,3’)
Jaws (4,4’),
Pliers Tip (5,5’)
Gripping surface (6,6’)
Pipe grips (7,7’)
Cutter (8,8’)
Comfortable grip (9,9’)

ADVANTAGES OF THE PRESENT INVENTION:

1) Present invention provides a fully insulated combination pliers for safety while in use at high voltage electrical power transfer cables up to 8 kV .

2) Present invention provides a reliable fully insulated combination pliers in cost effective way which can be used at high voltage electrical power transfer cables up to 8 kV safely.

Claims:WE CLAIM:
1. A fully insulated combination pliers for safety while in use at high voltage electrical power transfer cables, comprising:
first and second rigid members (1,1’), each having a handle portion (2, 2’), joint cutter (3,3’), jaws (4,4’) and pliers tip (5,5’), the members (1,1’) being joined in a scissors-like arrangement whereby the pliers tip (5,5’) are caused to move toward each other in response to the handle portions (2, 2’), being moved toward each other; wherein first and second rigid members (1,1’), have gripping surface (6,6’), pipe grips (7,7’), and cutter (8,8’), characterized in that the first and second rigid members (1,1’) fully being of insulated comprises a plurality of substantially flat lamination, including at least one inner insulation secured between oppositely-disposed outer insulation; wherein the said insulation is comprises alloy steel as a first layer , injection molding die as a second layer, and cellulose acetate as a third layer, wherein the said pliers can pass through high voltage up to 8 kV electrical power transfer cables.

2. The pliers as claimed in claim 1, wherein the handle portion (2, 2’) of the rigid member (1,1’), has a comfortable grip (9,9’) for easy handling.

3. The pliers as claimed in claim 1, wherein the alloy steel is chrome-vanadium steel.

4. The pliers as claimed in claim 1, wherein both the rigid members are connected to each other with the operation of riveting with alloy steel rivet on orbital riveting machine.

5. A process for insulation of combination pliers, wherein the said process comprises the steps of:
a) alloy steel forging as a first layer of insulation on the said pliers and machining it;

b) inserting the forged alloy steel pliers of step (a) in injection molding die at the temperature 65 degree to 75 degree as a second layer of insulation;

c) injecting cellulose acetate as third layer of insulation by injection molding machine in order to get the fully insulated combination pliers as claimed in claim 1.

6. The process for insulation of combination pliers as claimed in claim 5, wherein the alloy steel is steel containing additional alloying elements other than carbon selected from the group consisting of Ni, Cr, Mo etc.

7. The process for insulation of combination pliers as claimed in claim 5, wherein the alloy steel preferably used is chrome-vanadium steel.

8. The process for insulation of combination pliers as claimed in claim 5, wherein by using injection molding die as a second layer of insulation, the said pliers is capable to pass through high voltage up to 8 kV electrical power transfer cables.

9. The process for insulation of combination pliers as claimed in claim 5, wherein the insulation thickness is in the range of 2mm to 4mm.

10. The process for insulation of combination pliers as claimed in claim 9, wherein the insulation thickness is preferably 4 mm.