WO2005042213A1

WO2005042213A1 - Tool

Info

Publication number: WO2005042213A1
Application number: PCT/AU2004/001501
Authority: WO
Inventors: Michael Peter Wildon
Original assignee: Michael Peter Wildon
Priority date: 2003-10-31
Filing date: 2004-10-29
Publication date: 2005-05-12

Abstract

A hand tool (10) for performing a working operation (such as sawing) on a work-piece. The tool (10) comprises a first portion (11), a second portion (12) detachably connected to the first portion, and a tool element (31) mounted on the second portion. The second portion (12) provides a holder for the tool element (31) and is intended for exchange or replacement with the tool element. The tool element (31) is adapted to be driven by a drive motor (21), typically an electric motor which may be operable by battery. The motor (21) is accommodated within the first portion (11), and a coupling mechanism is provided between the first portion (11) and the second portion (12) for the drivingly connecting the motor (21) to the tool element (31). Typically, the tool element (31) comprises an endless band (33) adapted to move around an endless path. The second portion (12) comprises a pair of spaced apart limbs (25) with a run (37) of the endless band (33) extending between the limbs (25) adjacent the free ends thereof, whereby the run (37) of the band can be presented to a work-piece for performing an operation thereon.

Description

"Tool"

Field of the Invention

This invention relates to a tool for performing operations on a work-piece.

The tool has been devised particularly, although not solely, as a hand-held tool for performing sawing operations.

Background Art

Where intricate shapes are required to be cut from, or into, a work-piece, it is generally necessary to use a band saw or a jigsaw. Band saws have the benefit of providing support for the cutting blade on opposed sides of a work-piece. However, band saws are of a construction which is not readily portable. Accordingly, in circumstances where there is a need for a portable power tool the choice is usually restricted to a jigsaw.

Another limitation with bandsaws is that blade replacement can be cumbersome, which is not conducive to a target market where simplicity is a prime consideration.

It is against this background that at least one embodiment of the present invention has been developed.

Disclosure of the Invention

According to a first aspect of the present invention there is provided a tool comprising a first portion, a second portion detachably connected to the first portion, and a tool element mounted on the second portion.

Typically, the second portion provides a holder for the tool element and is intended for exchange or replacement with the tool element. Preferably, the first and second portions are each configured to facilitate gripping thereof by a user.

In particular, the first portion may be configured as a handle incorporating any controls for the tool. Such controls may comprise a release mechanism for detaching the first portion and the second portion, and any control switches for the tool.

Preferably, the tool is a power tool in which case the tool element is adapted to be driven by a drive motor, typically an electric motor which may be operable by battery. Conveniently, the motor is accommodated within the first portion, and a coupling mechanism is provided between the first portion and the second portion for the drivingly connecting the motor to the tool element.

In one arrangement, the tool element may comprise an endless band adapted to move around an endless path.

Where the tool element is configured as an endless band, it may be supported to pass around guide means provided on the second portion. The guide means may be of any appropriate form such as guide rollers.

The endless band may be drivingly engaged with a drive element (such as a drive pulley) drivingly connected to the drive motor.

The second portion may comprise a pair of spaced apart limbs with a run of the endless band extending between the limbs adjacent the free ends thereof, whereby the run of the band can be presented to a work-piece for performing an operation thereon.

In one arrangement, the first portion may define a space into which the second portion is removably received.

The tool element may comprise a cutting tool, such as a sawing element. Where the tool performs an operation other than cutting (for example, filing or polishing), the tool element for performing such an operation may also be configured as an endless band.

In another arrangement, the tool element may comprise a blade adapted to be heated for performing a heat cutting operation. This is particularly appropriate for cutting heat sensitive materials such as foam and polystyrene.

According to a second aspect of the invention there is provided a tool element and holder therefor for use with a tool according to the first aspect of the invention.

According to a third aspect of the invention there is provided a part for a tool, the part comprising the second portion of the tool according to the first aspect of the invention.

According to a fourth aspect of the invention providing a combination of a tool element and a holder therefor, the tool element comprising an endless band movable around an endless path, and the holder comprising a body defining a work-piece receiving space and a drive element in driving engagement with the endless band for moving the endless band around the endless path, the endless path having a portion thereof extending across said space.

According to a fifth aspect of the invention there is provided a hand tool comprising a body having a work-piece receiving space, and a tool element, the tool element comprising an endless band movable around an endless path and drive means for moving the endless band around the endless path, the endless path having a portion thereof extending across said space.

Preferably, the work-piece receiving space opens onto the periphery of the body.

Preferably, the body comprises a pair of spaced apart projecting limbs between which the work-piece receiving space is defined, the portion of the endless path extending across said space being located adjacent the free ends of the limbs. ln one arrangement, the body may be of unitary construction with the endless band supported therein.

In another arrangement, the body may comprise first and second body portions detachably connected together, with the endless band being mounted on the second body portion.

Brief Description of the Drawings

The invention will be better understood by reference to the following description of several specific embodiments thereof as shown in the accompanying drawings in which: Figure 1 is a schematic plan view of a tool according to a first embodiment;

Figure 2 is a side view of the tool;

Figure 3 is a similar view to Figure 2 with the exception that is shown as two parts detached;

Figure 4 is a schematic side view of the tool illustrating a saw blade used in the tool and a mechanism for driving the saw blade;

Figure 5 is a fragmentary plan view of a saw blade for use with the tools according to the first embodiment;

Figure 6 is an end view of the saw blade;

Figure 7 is a fragmentary perspective view of the saw blade on an enlarged scale;

Figure 8 is a schematic side view of a tool according to a second embodiment;

Figure 9 is a schematic side view of a first part of the tool of Figure 8; and Figure 10 is a schematic side view of a second part of the tool according to the second embodiment.

Best Mode(s) for Carrying Out the Invention

Referring to Figures 1 to 7 of the drawings, there is shown a tool 10 according to the first embodiment for performing sawing operations on a work-piece (not shown).

The tool 10 has a tool body comprising a first body portion 11 and a second body portion 12. The two body portions 11 , 12 are adapted to be detachably connected together. In this regard, the second body portion 12 has a section 13 at one end thereof defining a spigot 14 adapted to be received in a complementary socket 14 formed in an adjacent end section 15 of the first body portion 11.

The first body portion 11 includes a locking mechanism operable by way of an element 17, such as a button, for releasably securing the two body portions 11 , 12 together when the spigot 14 on the second body portion 12 is received in the socket of the first body portion 11.

The first body portion 11 is configured to define a hand grip portion 18, and the second body portion 12 as configured to define a further hand grip portion 19.

The first body portion 11 includes a drive motor 21 and a drive cog 23 drivingly connected to the drive motor. The drive motor 21 is powered by a power source, such as a battery (not shown) accommodated within the first body portion 11 , or alternatively from a mains supply. A switch 22 is provided for controlling operation of the drive motor 21.

The second body portion 12 includes a pair of spaced apart limbs 25 extending from the end section 13 and defining a work-piece receiving space 27 therebetween. The space 27 opens onto the periphery of the tool 10 adjacent the free ends of the limbs 25, as shown in the drawings. The tool 10 further includes a tool element 31 for performing a sawing operation on a work-piece. The tool element 31 is accommodated in a housing 32 formed by the second body portion 12. In this way, the second body portion 12 provides a holder for the saw blade 31. In this embodiment, the tool element 31 comprises a saw blade configured as an endless band 33.

The endless band 33 providing the saw blade passes around guide means 35 in the form of guide rollers 36 mounted on the second body portion 12. The guide rollers 36 include two end rollers 36a, one mounted on each limb 25 adjacent the free end thereof. With this arrangement, the endless band 33 travels around an endless path which traverses the space 27 adjacent the free ends of the limbs 25 such that there is a run 37 of the endless band which extends across the space 27.

A further run 39 of the endless band 33 passes over a drive pulley 41 in frictional engagement therewith. The drive pulley 41 is drivingly coupled to a driven gear 43 which meshes in driving engagement with the drive cog 23 when the first and second body portions 11 , 12 are connected together, as shown in Figure 4 of the drawings. With this arrangement, drive from the motor 21 is transferred through meshing gears 23, 43 to the drive pulley 41 which then drives the endless band 33 around its endless path. The drive pulley 41 and the meshing gears 23, 43 thus co-operate to provide a coupling mechanism for drivingly connecting the motor 21 to the tool element 31.

The endless band 33 can be of any appropriate form. In this embodiment, the endless band comprises a multitude of intertwined strands 45, as best seen in Figures 5, 6 and 7. The strands 45 may be of any appropriate material such as wire. The strands 45 have protrusions 47 thereon which form teeth on the intertwined structure. Such a blade construction allows a sawing operation to be performed from any direction relative to the blade.

The housing 32 may be disposable in a sense that it is replaced each time a replacement saw blade 31 is required. In other words, the saw blade 31 is supplied fitted into the housing 32 defining by the second body portion 12 which is simply then connected to the first body portion 11 , as described previously. As the two body portions 11 , 12 are fitted together, the gears 23, 43 move into meshing engagement. No further action is required on the part of the user in order to fit the replacement blade 31 to the tool 10 and prepare it for operation. This arrangement also facilitates easy exchange of saw blades 31. In this regard, it may be there are various types of saw blades 31 available for different cutting techniques and materials. Each saw blade 31 would be accommodated in its own housing 32 which can be fitted onto, and removed from, the tool 10 as necessary.

Because of the elongate nature of the two limbs 25, the space 27 defined therebetween is elongated so as to provide a clearance into which a work-piece can extend during a cutting operation.

The tool 10 according to the first embodiment can be used for any appropriate cutting operation. One particular application of the tool 10 is in the surgical arena as a sternal saw for open heart surgery.

Referring now to Figures 8, 9 and 10, the tool 10 according to the second embodiment is similar in many respects to the tool according to the first embodiment except for the manner in which the first and second body portions 11 , 12 are detachably connected together. In this embodiment, the first body portion 11 includes a section 51 defining a slot 53 into which the second body portion 12 is slidably received and retained. The section 51 includes two spaced apart rails 55 between which the second body portion 12 is engaged, as shown in Figure 8 of the drawings. When the second body portion 12 is fully engaged within the first body portion, the gears 23, 43 are in meshing engagement such that drive applied by the motor 21 is transmitted through the intermeshing gears to the drive pulley 41 which in turn drives the tool element 31 around its endless path. As was the case with the first embodiment, in this embodiment the second body portion 12 may be adapted for a single use only such that it is disposed of at the time the saw blade 31 requires replacement. Similarly, it can be exchanged as required.

In this embodiment, both grip portions 18, 19 are provided on the first body portion 11. From the foregoing it is evident that the present invention provides a simple yet highly effective tool which allows ready replacement of tool elements as required.

The two embodiments described both relate to tools for performing sawing operations. It should be understood that the invention may also be applied to tools for performing working operations other than sawing, including filing and buffing. In such cases all that would be required is to provide the endless band 33 in an appropriate form for the required purpose.

It should also be understood that the invention need not necessarily be limited to an arrangement where the tool element is in the form of an endless band. By way of example, where a tool is required for performing a heat cutting operation on materials such as polystyrene and foam, the tool element may comprise an electrically conductive cutter element (such as a wire) spanning the space between the free^'ends of the limbs 25 on the second body portion 12. The cutter element would then be electrically connected to an electrical supply carried in the first body portion 11 , such that when an electrical circuit incorporating the cutter element was closed, the cutter element would be heated through electrical resistance in order to perform a cutting operation.

Further, it should also be understood that the tool according to the invention may be adapted to receive accessories to broaden the utility and functionality of the tool. By way of example, the tool may have an accessory such as a vacuum cleaner head which can be connected to the first body portion 11 for performing vacuum cleaning functions.

Improvements and modifications may be incorporated without departing from the scope of the invention.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims

The Claims Defining the Invention are as Follows

1. A tool comprising a first portion, a second portion detachably connected to the first portion, and a tool element mounted on the second portion.

2. A tool according to claim 1 wherein the second portion provides a holder for the tool element.

3. A tool according to claim 1 or 2 wherein the first and second portions are each configured to facilitate gripping thereof by a user.

4. A tool according to claim 3 wherein the first portion is configured as a handle.

5. A tool according to claim 4 wherein the handle incorporates controls for the tool including a release mechanism for detaching the first portion and the second portion.

6. A tool according to any one of the preceding claims wherein the tool element is adapted to be driven by a drive motor, typically an electric motor.

7. A tool according to claim 6 wherein the drive motor is accommodated within the first portion, and a coupling mechanism is provided between the first portion and the second portion for the drivingly connecting the drive motor to the tool element.

8. A tool according to any one of the preceding claims wherein the tool element comprises an endless band adapted to move around an endless path.

9. A tool according to claim 8 further comprising guide means for supporting the endless band for movement around the endless path.

10. A tool according to claim 9 wherein the guide means comprises guide rollers.

11. A tool according to claim 8, 9 or 10 further comprising a drive element (such as a drive pulley) drivingly connected to the drive motor, the drive element being adapted for driving engagement with the endless band.

12. A tool according to any one of claims 8 to 11 wherein the second portion comprises a pair of spaced apart limbs with a run of the endless band extending between the limbs adjacent the free ends thereof, whereby the run of the band can be presented to a work-piece for performing an operation thereon.

13. A tool according to any one of the preceding claims wherein the tool element comprises a cutting tool.

14. A part for a tool according to any one of the preceding claims, the part comprising the second portion of the tool.

15. A tool element and a holder therefor for use with a tool according to any one of claims 2 to 13.

16. A combination of a tool element and a holder therefor, the tool element comprising an endless band movable around an endless path, and the holder comprising a body defining a work-piece receiving space and a drive element in driving engagement with the endless band for moving the endless band around the endless path, the endless path having a portion thereof extending across said space.

17. A combination according to claim 16 wherein the work-piece receiving space opens onto the periphery of the body.

18. A combination according to claim 16 or 17 wherein the body comprises a pair of spaced apart projecting limbs between which the work-piece receiving space is defined, the portion of the endless path extending across said space being located adjacent the free ends of the limbs.

19. A combination according to claim 16, 17 or 18 further comprising guide means for supporting the endless band for movement around the endless path.

20. A combination according to claim 19 wherein the guide means comprises guide rollers.

21. A hand tool comprising a body having a work-piece receiving space, and a tool element, the tool element comprising an endless band movable around an endless path and drive means for moving the endless band around the endless path, the endless path having a portion thereof extending across said space.

22. A hand tool according to claim 21 wherein the work-piece receiving space opens onto the periphery of the body.

23. A hand tool according to claim 21 or 22 wherein the body comprises a pair of spaced apart projecting limbs between which the work-piece receiving space is defined, the portion of the endless path extending across said space being located adjacent the free ends of the limbs.

24. A tool substantially as herein described with reference to the accompanying drawings.

25. A combination of a tool element and a holder therefor as herein described with reference to the accompanying drawings.