AU2007100421A4

AU2007100421A4 - Pipe Cutting Attachment

Info

Publication number: AU2007100421A4
Application number: AU2007100421A
Authority: AU
Inventors: Evan Graham
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-05-23
Filing date: 2007-05-23
Publication date: 2007-06-21
Anticipated expiration: 2015-05-23

Description

AUSTRALIA

Patents Act 1990 INNOVATION PATENT

SPECIFICATION

200710 Filed 2 3 rd May 2007 Invention Title Pipe Cutting Attachment Applicant: Evan Graham Innovator: Evan Graham The innovation is described in the following statement: PIPE CUTTING ATTACHMENT This innovation relates to an attachment to a power tool for use by plumbers in doing maintenance and renovations.

Background to the innovation In making plumbing repairs, PVC pipes embedded in concrete often need to be replaced. The present practice is to remove the concrete cover to expose the buried pipe and then cut the old pipe and fit an elbow or new pipe to the cut end.

This is a time consuming process.

There has been some attempts to address this problem usually by providing a means to internally cut the existing pipe below the level of the concrete.

USA 3911574 discloses an internal pipe cutter with radially extendable saw blades which move outwardly by centrifugal force. A depth guide is a part of the fitting.

USA patent 4576070 discloses an internal cutting attachment for a power drill having a radial disc blade attached to a shaft and includes a guidance component.

USA 4932125 discloses a cutting attachment with a height guide slidable on the blade shaft.

USA patent 5815926 discloses a power tool attachment comprising a disc blade a shaft and a guide collar.

None of these systems are commercially available in Australia and this may be because of the cost, difficulty of use and storage space required by these proposals.

It is an object of this innovation to provide an internal pipe cutter that is inexpensive, easy to use and easy to store and transport.

Brief description of the innovation To this end the present innovation provides an internal pipe cutter consisting of a two piece power drill attachment which consists of a cutting disc with a central attachment hole and a shaft at one end adapted to be secured to the disc and the other end shaped to fit a drill chuck. The shaft is chosen to be long enough to allow the pipe to be cut a sufficient distance below the concrete surface so that the new pipe section may be supported. A length of at least 60 mm from the chuck to the disc is required.

Instead of breaking concrete to expose a pipe the pipe can be cut internally below the surface of the concrete so that an elbow or new pipe can be inserted and joined to the old pipe.

For maintenance and renovation work the attachment of this invention can easily be carried in a tool box and fitted to a power drill when needed. The length of the shaft is chosen so that the end of the cut pipe is below the concrete or floor surface and the new pipe or elbow can be inserted to be joined to the old pipe.

The cutting blade is a disc that can easily be replaced when worn.

Detailed description of the innovation A preferred embodiment of the innovation is illustrated in the drawings in which Figure 1 is a perspective view of the cutting attachment from above and below; Figure 2 is an exploded view of the attachment of figure 1; Figure 3 is a sectional view of the shaft; Figure 4 is a plan view of the blade.

The attachment 10 consists of a shaft 12 having one end 14 for insertion in the chuck of a power drill and the other end 16 has a screw threaded hole 17 extending axially into the shaft 12. A cutting blade 20 is secured to the end 16 of the shaft 12 by a bolt 23 and its associated washer 24. The bolt 23 is screwed into the hole 17 in shaft 12.

The distance from the power tool chuck to the blade is about 70mm which is sufficient to provide a cut of sufficient depth to ensure an effective joint can be formed.

Those skilled in the art will realize that this innovation provides a convenient, simple to use and cost effective tool. Those skilled in the art will realize that this innovation may be implemented in embodiments other than that described herein, without departing from the core teachings of this innovation.

Claims

1. A two piece power drill attachment for cutting PVC pipes internally which consists of a cutting disc with a central attachment hole and a shaft at one end adapted to be secured to the cutting disc and at the other end shaped to fit a drill chuck wherein the length of the shaft is at least

2. An attachment as claimed in claim 1 in which the disc is replacable.