AU2008100681A4 - Insert tool for wire thread inserts - Google Patents

Description

P01l Secton 29 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT 00

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oo 0 Application Number: Lodged: Invention Title: Insert tool for wire thread inserts The following statement is a full description of this invention, Including the best method of performing it known to us: 00 INSERT TOOL FOR WIRE THREAD INSERTS c FIELD OF THE INVENTION The present invention is generally directed to wire thread inserts used in Sthe repair of pre-existing threaded bores having a damaged thread, or to form a new thread for a bore within a substrate, and is in particular directed to an insert tool for installing such wire thread inserts.

00oo 1-1 BACKGROUND OF THE INVENTION Wire thread inserts are conventionally provided by a wire formed into a 00oO closed coil configuration, with the coiled insert having an inner and outer surface.

0 10 The cross-section of the wire is typically diamond shaped and is coiled such that one portion of the coiled wire forms an inner helical thread for the inner surface of the insert, while the other portion of the coiled wire forms a second helical thread for the outer surface of the insert which is adapted to engage a helical thread provided in a bore within a substrate.

These wire thread inserts are typically used to repair threaded bores where the thread has been damaged or stripped. They can also be used to provide a new thread for a bore.

The normal procedure for repairing an existing threaded bore and for installing such a wire thread insert is as follows: a) passing a drill bit through the bore to clean out and remove the remaining sections of the origin helical thread; b) using a tap to provide a new helical thread within the drilled bore, this helical thread having a diameter greater than the original helical thread of the bore; c) inserting the wire thread insert by means of an insert tool which engages a tang or notch on the inner surface provided at the end of the insert and twists and temporarily narrows the diameter of the insert thereby allowing the insert to enter and engage the female helical thread in that bore; d) releasing the insert such that it springs outwardly again to more tightly engaging the threaded bore; and e) finally breaking or twisting off the tang when and if provided at the end of the wire thread insert.

00 O A torsional force may be applied to the wire thread insert to thereby initially N twist and compress that insert such that it can be readily wound into the helical thread. Once the torsional force is removed from the thread insert, that insert expands outwardly to secure the engage the female helical thread provided within the threaded bore. Alternatively, the insert tool can compress the insert prior to and during installation of the insert. This ensures that the thread insert remains 00

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N securely in place when a bolt is subsequently inserted and engages the new

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Ofemale helical thread provided by the inside surface of that thread insert. A 00 similar procedure is followed where the insert is being used to provide a new C 10 helical thread within a bore.

The applicant typically sells a thread repair kit incorporating a number of wire thread inserts together with a tap, an insert tool, and a tang removal tool. As noted above, the tap is sized to cut the appropriate thread for the wire thread insert. A (tap) wrench needs to be provided by the end-user of the thread repair kit, as this wrench is not included within the kit. The installation tool is typically formed from a metal cylindrical rod having a diameter which is narrower than the internal diameter of the wire thread insert. At one end of the rod is machined a slot for engaging the tang of the wire thread insert. An adjustable metal collar is also secured on the metal rod adjacent to the slot to provide a stop for the wire thread insert when located on the end of the tool and prevent that insert from sliding up the rod of the tool. The other end of the metal rod is formed into a "7" shape to provide a handle to enable turning of the insert tool about its elongate access. The handle end of the insert tool is typically coated with a plastic skin to make it easier to grasp and rotate the insert tool.

The tang removal tool is typically a straight piece of metal rod coated with plastic along most of its length with an exposed lower end. The exposed lower end can be inserted through the internal diameter of the wire thread insert when installed and is used to break off the tang at the end of the installed wire thread insert.

A disadvantage associated with such thread repair kits is that it is necessary for the user to provide a tap wrench to turn the tap. However, particularly in the DIY market, a person buying such a kit may not have all the necessary tools to complete the job. It is also not economically viable to provide 00 a tap wrench within each wire repair kit. Furthermore, because the handle end of the insert tool is essentially formed from a deformed end of the metal rod, it can be uncomfortable to use because the handle is relatively narrow in diameter, even with the plastic coating on the rod. Also, the manufacture of the insert tool requires a number of different manufacturing processes, and it would be preferable to be able to use more cost effective manufacturing processes using, oo 00 N for example, plastic injection moulding. The use of such manufacturing O processes can lead to a significant reduction in manufacturing costs.

00 SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a tool for wire thread inserts that is multi-purpose and provides design benefits that over comes the traditional disadvantages and in addition improves the level of achievable workmanship by the "DIY" installer. The tool has been developed as a "one stop" solution, which doesn't require other hand tools to complete the installation.

With this in mind, the present invention provides an insert tool for a wire thread insert including a handle portion having an opening for accommodating a drive end of a tap, and a rod extending from an end of the handle portion, the peripheral end of the rod being provided with a slot for engaging a wire thread insert.

The tap typically has a cutting end for cutting the thread, and an opposing drive end which is accommodated within a tap wrench or other tool for enabling the tap to be rotated within a bore. The drive end may typically have a squared off cross-section to facilitate accommodation within said tap wrench.

In the insert tool according to the present invention, the opening provided within the handle portion may also be shaped to accommodate the tap drive end.

The opening may be a cavity provided in the handle portion or may be a passage extending completely through the handle portion. The opening may be located at or adjacent the end of the handle portion from which the rod extends. The insert tool may therefore also act as a tap wrench with the handle portion and the rod acting respectively as the lever arms of the tap wrench.

The handle portion may include a main body within which is located the opening and from which the rod extends, and may further include a handle extension extending from the main body in a generally opposing direction from 00 O the rod to facilitate the rotation of the insert tool. The handle extension may also N be in the form of a "seven" as with the currently used tools, but may have a significantly wider diameter than the known tools. This facilitates comfortable operation of the insert tool. The handle portion may preferably also be formed using a polymer moulding process. For example, the handle could be formed from cellulose acetate butyrate (cab), a plastic which is commonly used for oo 00 N applications such as screwdriver handles. The use of other forms of plastic or 0 Sother materials are however also envisaged.

00oo The shaft may be integrally moulded into the handle portion during the 0 10 plastic injection moulding process thereby facilitating the production of this insert tool.

A collar may also be provided on the shaft adjacent the slot to provide a stop for the wire thread insert. The collar may be formed in two sections, with the first section being an internal sleeve having an external threaded surface, and the second section being an outer locking nut having a generally frustoconical inner threaded bore. The inner sleeve has an internal passage such that sleeve can be slid once and accommodated on the rod. The second section may be threaded onto the inner sleeve to thereby act as a locking nut which urges the inner sleeve onto the rod and securely engages the collar onto the rod.

The use of a conventional collar incorporating a collar ring, and a tightening screw extending radially through the collar is however also envisaged.

The insert tool according to the present invention eliminates the need to have separate tools including a tap wrench to drive the tap. Furthermore, the insert tool can be manufactured using more cost effective production processes such as polymer moulding. The insert tool is also more ergonomic to use, in part because of the thicker body associated with the handle portion of the insert tool and developed to improve the ease of use for the un-trained installers.

BRIEF DESCRIPTION OF THE DRAWINGS It will be convention to further describe the invention with respect to the accompanying drawings which illustrate a preferred embodiment of the insert tool according to the present invention. Other embodiments of the invention are possible, and consequently, the particularity of the accompanying drawings is not 00 O to be understood as superseding the generality of the preceding description of the Sinvention.

In the drawings: Cc Figure 1 is a side view of an insert tool according to the present invention; and Figure 2 is a side cross-sectional view of the insert tool of Figure 1 taken o00 11along line C-C.

0The insert tool according to the present invention includes a handle portion 00oo 1 from which extends a rod 5. At the end of the rod 5 is provided a slot 7 for 0 10 engaging a wire thread insert.

The handle portion 1 includes a main body 9 within which is located an opening 3. This opening 3 has a generally square cross-section and is sized to accommodate the drive end of a tap (not shown). A rod 5 extends from the main body 9, a slot 7 being provided at the peripheral end of the rod 5 for engaging the tang of a wire thread insert (not shown). A handle extension 11 extends from the main body 9 in a generally opposing direction to the rod 5. The handle extension 11 is configured in a "seven" shape in a similar manner to existing insert tools.

The diameter of the handle extension 11 is however significantly larger than the diameter of a corresponding known insert tool.

A collar 13 is located on the rod 5 adjacent to the slot 7. The collar 13 includes a first section 15 in the form of a inner sleeve having an external threaded surface 17 and an internal passage 18. The internal passage 18 is dimensioned to allow the collar 13 to slide over the rod 5. The collar 13 further includes an outer locking nut 19 having an internally threaded surface 21 which is adapted to engage the external threaded surface 17 of the inner sleeve 15. The inner threaded surface 21 of the locking nut is generally frustoconical in shape.

As the locking nut 19 is threaded onto the external threaded surface 17, the inner sleeve 15 is urged against the rod 5 to thereby secure in position the collar 13 on that rod.

The insert tool according to the present invention is also adapted to be used as a tap wrench with the rod 5 and handle extension 11 acting as the lever arms of the tap wrench while the drive end of the tap is located within the opening 3. This eliminates the need for a separate tap wrench to be provided.

6 00 Furthermore, the insert tool according to the present invention can be c manufactured using cost-effective manufacturing processes such as plastic injection moulding. This leads to significant savings in manufacturing costs.

SThe insert tool according to the present invention can effectively replace three tools and may be ergonomically designed to improve the ease of operation and successful operation for a "DIY" user.

00oo IDModifications and variations as would be deemed obvious to the person skilled in the art are included within the ambit of the present invention as claimed 00oo in the appended claims.

Claims (2)

1. 2. An insert tool according to claim 1, wherein the handle portion includes a main body within which is located the opening and from which the rod extends, 00 Sand further includes a handle extension extending from the main body in a Sgenerally opposing direction from the rod.
2. 3. An insert tool according to claim 1 or 2 further including a collar located on the rod adjacent the slot, the collar including a first section including and inner sleeve having an external threaded surface, and a second section including a lock nut with a generally frustoconical internal threaded bore for engaging the external threaded surface of the inner sleeve to thereby urge the inner sleeve onto the rod. ALCOA FASTENING SYSTEMS AUSTRALIA PTY LTD WATERMARK PATENT TRADE MARK ATTORNEYS