Composite socket tool

Abstract

 A socket tool is formed primarily from nonmetallic composite material. The socket tool body is compression molded to net shape using high strength, E-glass reinforced (60-65% weight random glass fibers approximately one inch long) vinyl ester sheet molding compound. Since it consists entirely of nonmetallic materials, the socket body demonstrates unique qualities, including being nonconductive, nonsparking, corrosion resistant, lightweight, nonmagnetic and low marring. The outer wall of the socket features a molded serrated finish texture, providing a convenient grip surface. The square drive end of the socket incorporates an insert-molded metal insert in order to bear the high contact stresses from a ratchet drive square. The metal insert is electrically isolated from the exterior walls and hex opening of the socket so as not to compromise the electrical insulating and nonsparking qualities of the tool.

Description

Background of the Invention

1. Field of the Invention

[0001] The present invention relates generally to socket wrench tools and the like and, more particularly, to a composite socket wrench tool which is made almost entirely of glass-reinforced composite material.

2. Description of the Prior Art

[0002] Conventionally, socket wrench tools and like wrenching tools have been made of iron, steel, or some other metal, because of strength and durability requirements. Metal tools are manufactured using machining and/or casting or forging procedures. An important disadvantage of metal tools is their cost, both from manufacturing and material standpoints. Moreover, metal tools are unsuitable for use in many applications, particularly when a shock hazard condition exists. Use of metallic tools on nonmetallic fastening members such as nonmetallic nuts, bolts and the like is also undesirable because such fastening members are often marred or otherwise damaged by the hardness of the tool.

[0003] Insulated socket tools have been proposed which include both metal and plastic, the plastic generally forming the outside of the socket tool. An insulated tool is simply a standard conductive metal tool covered with an insulating layer or coating. This insulating layer can be easily damaged or deteriorated to a point where the insulating properties of the tool are severely compromised and pose a threat to the safety of the user. It would be a significant advancement in the art to be able to provide a socket tool that has inherent or "built-in" insulation properties. Such a tool would be safer for use on or near live electrical circuits and would offer a higher level of protection for the electrical components themselves.

[0004] The method for making composite tools from glass fiber-reinforced molded material is well known. In U.S. Patent No. 5,271,300, there is disclosed a totally nonmetallic hand tool formed entirely of a composite material, which is inexpensive to manufacture and meets the strength requirements for that of a metal tool of comparable size. More specifically, the wrench tool is made of glass fiber-reinforced plastic material which is nonmetallic and therefore nonmagnetic, nonconductive, and nonsparking. The respective wrench box ends are optionally featured with premolded inserts which are compression molded into the composite wrench body during the molding process. It would be advantageous to provide an insulating socket having the strength and dimension of a metal tool of comparable size.

Summary of the Invention

[0005] It is a general object of the invention to provide an insulating socket tool made from a composite material and including a metallic insert formed therein.

[0006] It is another object of the present invention to provide a socket tool which is made from a non-conductive, nonsparking, corrosion resistant material having dimensions and structural strength that approximate that of metallic sockets of like size.

[0007] These and other features of the invention are attained by providing a socket tool including an elongated body and having an exterior surface, and having a driven end opening and a driving end opening respectively defined by associated interior surfaces. Further included is a metal insert disposed in one of the openings and electrically isolated from the other of the openings, and having a cavity therein for mateably receiving a corresponding one of an associated driving element and a driven element.

[0008] The invention consists of certain novel features and a combination of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the details may be made without departing from the spirit, or sacrificing any of the advantages of the present invention.

Brief Description of the Drawings

[0009] For the purpose of facilitating an understanding of the invention, there is illustrated in the accompanying drawings a preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, the invention, its construction and operation, and many of its advantages should be readily understood and appreciated.

FIG. 1 is a side elevation view in partial section of a socket tool constructed in accordance with and embodying the features of the present invention;

FIG. 2 is a left end elevation view of the socket tool of FIG. 1 showing the socket square drive end;

FIG. 3 is a right end elevation view of the socket tool of FIG. 1 showing the socket hex drive end;

FIG. 4 is a view, similar to FIG. 1, of a socket tool in accordance with a second preferred embodiment;

FIG. 5 is a left end elevation view of the socket tool of FIG. 4 showing the socket square drive end; and

FIG. 6 is a right end elevation view of the socket tool of FIG. 4 showing the socket hex drive end.

Detailed Description of the Preferred Embodiments

[0010] Referring to FIGS. 1-3, there is illustrated a composite socket tool 10 constructed in accordance with and embodying the features of the present invention. The socket tool 10 consists of an elongated body 11 and a metal insert 30 insert molded in the body 11. The elongated body 11 includes a driven end portion 12 of circular-cylindrical shape, and a driving end portion 13 also of circular-cylindrical shape but having a cross-sectional diameter slightly greater than that of the driven end portion 12. The outside surface of the driven end portion 12 includes serrations 14 providing a convenient grip surface.

[0011] The driven end portion 12 includes a metal-insert-receiving opening 15 having an interior flat base surface 16 closing the inner end of an inside peripheral surface 17 of circular transverse cross-section (see FIG. 2). The driving end portion 13 includes a fastener-receiving opening 18 having a flat circular base surface 19 and a side wall surface 20. The nut-receiving opening 18 and metal-insert-receiving opening 15 are noncommunicating and separated by a wall 21.

[0012] The side wall surface 20 of opening 18 includes an inner circular-cylindrical portion 23 and an outer fastener receiving portion 24. The portion 24 is cross-sectionally dimensioned to mateably receive a hex-shaped fastening member for imparting a rotational driving force thereto, although other polygonal shapes could be used. The axial length of the fastener receiving portion 24 must be such as to accommodate a variety of different length fastening members, and may be of various axial extents, as desired.

[0013] Opposite ends of the elongated body 11 respectively define a driving end 25 and a driven end 26 which are slightly chamfered at their respective perimeters to reduce scratching and prevent surface damage by the socket tool 10. The fastening-member-receiving portion 24 of opening 18 is also chamfered at its outer end.

[0014] As to the material construction of the socket tool 10, the elongated body 11 is compression molded to shape by conventional composite molding techniques using a high-strength, E-glass reinforced (60-65% weight random fibers approximately one inch long) vinyl ester sheet molding compound. Before the molding process, the metal insert 30 is first positioned in the mold cavity, and the body 11 is molded around the insert 30. The metal insert 30 has an axial cavity 31 defined by a square cross-sectional portion 33 with a generally flat base 32. A portion of the outer surface of the metal insert 30 is knurled to prevent rotation within the opening 17. The portion 33 is appropriately sized to mateably receive the drive stud of a driving tool (not shown). The outer end portion 33 may be chamfered, as at 35.

[0015] The metal insert 30 is electrically isolated from all exterior wall surfaces and from the fastener-receiving opening 18 of the elongated body 11 so as not to compromise the insulating (non-conductive) and nonsparking qualities of the socket tool 10. The composite socket tool 10 has strength and dimensioning similar to those of conventional metal sockets. Since the insert 30 is metallic, it is better suited than an all nonmetallic composite socket tool for bearing the high contact stresses from the drive stud.

[0016] The socket tool 10 of FIGS. 1-3 is intended to replace like metal/steel sockets and insulated or plastic coated standard steel sockets, such as 3/8" and 1/2" square drive sockets.

[0017] Referring now to FIGS. 4-6, there is shown a socket tool 10' constructed in accordance with an alternate embodiment of the present invention, having an elongated body 11' and, more specifically, a driving end portion 13', which is dimensionally different than that of socket tool 10 of FIGS. 1-3, for use with large size hex fastening members. In the illustrative embodiment, a socket tool 10' is a 7/8" hexagon socket tool with a 3/8" square drive metal insert 30. It should be appreciated that like numerals as those used for the socket tool 10 of FIGS. 1-3 are used to refer to like elements. Socket tool 10' is constructed in the same manner as described above in connection with socket tool 10, and molded in the shape generally shown in the drawings (FIGS. 4-6).

[0018] Socket tool 10' features a driving end portion 13', a portion of the outer wall of which is tapered in a radially expanding manner to provide a fastener-receiving opening 18' having a first circular-cylindrical portion 23a and a second circular-cylindrical portion 23b separated by a frustoconical surface portion 23c. The fastener receiving portion, shown by the numeral 24', is similarly shaped cross-sectionally as the portion 24 of socket tool 10 in FIG. 1, but is uniquely sized to mateably receive a hex type fastening member having a large cross-sectional width.

[0019] Testing of a molded 7/8" composite socket tool 10 constructed in accordance with the present invention showed that its average ultimate torque strength exceeds minimum ANSI requirements for comparably-sized steel sockets and offers a 37% weight savings. Also, the molded serrations 14 were found to offer superior gripping ability over steel sockets allowing for easier manual manipulation and finger turning of the socket.

[0020] While particular embodiments and several specific forms of tools of the present invention have been shown and described, it will be appreciated by those skilled in the art that additional changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.

Claims

1. A socket tool comprising a nonmetallic elongated body having an exterior surface and having a driven end opening and a driving end opening respectively defined by associated interior surfaces, and a metal insert disposed in one of said openings and electrically isolated from the other of said openings and having an opening therein for mateably receiving a corresponding one of associated driving and driven elements.

2. The socket tool of claim 1, wherein said elongated body is made from a plastic material.

3. The socket tool of claim 1, wherein said elongated body is made from glass fiber-reinforced composite material.

4. The socket tool of claim 1, wherein said elongated body is made from a compression molded high strength, E-glass reinforced vinyl ester material.

5. The socket tool of claim 1, wherein said elongated body is made from a nonconductive, non-sparking, corrosion resistant material.

6. The socket tool of claim 1, wherein said exterior wall surface includes a serrated surface portion providing a convenient grip surface.

7. The socket tool of claim 1, wherein said metal insert is disposed in said driven end opening.

8. The socket tool of claim 7, wherein said metal insert is insert-molded within said elongated body.

9. The socket tool of claim 8, wherein said driven end opening encases the whole length of said insert-molded metal insert.

10. The socket tool of claim 1, wherein said driven end opening and said driving end opening are separated by a wall portion extending transversely of said body.

11. The socket tool of claim 1, wherein said driving end opening is polygonal in transverse cross-section.

12. The socket tool of claim 1, wherein said insert has an outer surface circular in transverse cross-section with knurls on at least a portion of said outer surface.

Drawing