AU2010202744A1 - Sharpening Tool - Google Patents

Description

r-uuiu i i otuu i Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Dreamweaver Studios Pty Ltd Actual Inventors Antonia Bandera and Joanne Watts Address for service is: WRAYS Ground Floor, 56 Ord Street West Perth WA 6005 Attorney code: WR Invention Title: Sharpening Tool The following statement is a full description of this invention, including the best method of performing it known to me: 1 Sharpening Tool Field of the Invention The present invention generally relates to a sharpening tool for providing /maintaining a sharp edge on a cutting instrument such as a knife. 5 Background Art The use of a sharpening tool such as a stone or sharpening rod to sharpen the cutting edge of a knife is well known. In the food preparation industry and other similar industries it is essential for a worker to have sharp knives and to be able to maintain the sharpness of those 10 knives. In order to maintain the sharpness a sharpening tool which is conventionally known as a "sharpening steel" is used. Currently sharpening tools are generally problematic when it comes to ensuring the cutting edge is sharpened at the correct angle. In sharpening a blade utilising a sharpening steel the nature of the movement of the blade over the sharpening 15 steel and the angle of the blade relative to the sharpening steel is critical to ensure proper sharpening of the blade. This is particularly difficult as it is up to the skill of the operator to maintain the angle of the knife relative to the sharpening tool during the sharpening process. Whilst the task of sharpening the blade utilising a sharpening steel appears to be 20 relatively straightforward there are several misunderstandings in relation to the use of the sharpening steel which results in the improper use of the sharpening steel to sharpen the knife. For instance failure to maintain a consistent angle results in a non-uniform cutting edge and will often further blunt the cutting edge as opposed to sharpening. 25 Another problem is that most sharpening tools grind material away from the knife edge in order to provide a new cutting edge. Eventually continuous sharpening wears away the knife until such a point it must be discarded. This is particularly 2 the case with butchers and chefs who constantly maintain a sharp edge on their knives. Furthermore, the sharpening process presents a safety hazard as often the user holds the sharpening tool and knife in a manner whereby fingers may extend 5 outwardly from the sharpening tool such that they fall within the path of the knife as it is sharpened. The preceding discussion of the background to the invention is intended only to facilitate an understanding of the present invention. It should be appreciated that the discussion is not an acknowledgment or admission that any of the material 10 referred to was part of the common general knowledge as at the priority date of the application. SUMMARY OF INVENTION It is an object of this invention to provide to ameliorate, mitigate or overcome, at least one disadvantage of the prior art, or which will at least provide the public 15 with a practical choice. The present invention provides a sharpening tool comprising a handle, a rod and a guide located at an interim position between the handle and an end of the rod, the guide providing a guide face, the guide face being at an angle relative to the rod whereby the angle is such that a knife positioned first on the guide is 20 presented to the rod at the optimum angle for sharpening. The guide face may be treated so as to provide traction when a knife blade engages the guide face. The guide face may be rough to the touch. The guide face may be knurled whereby a plurality of spaced coaxial rings is engraved on the guide face. If the guide face was a smooth surface the operator would find it 25 difficult to maintain the angle between the knife and the rod. The rings may be two microns in radial height. The guide may be spaced a distance from the handle to allow for wider knife blades to be correctly positioned. 3 The rod may be adapted such that the grinding effect upon the cutting edge is minimal. The rod may be adapted such that the cutting edge (as may be viewed under a microscope) is realigned with the plane of the blade during the sharpening process. The rod may be adapted such that during the sharpening 5 process the microscopic serrated teeth of the cutting edge are realigned with the plane of the blade. The rod may be etched. The rod may have a plurality of lines incorporated in or on the surface, the lines being parallel with the longitudinal axis of the rod. 10 The rod may be etched and have a plurality of lines incorporated in or on the surface. By having the rod etched and/or lined the operator is able to obtain more consistent traction of the blade on the rod. The treatment of the rod in this manner also helps to realign the serrated teeth as opposed to grinding them from 15 the knife. An end of the handle remote from the guide may have a projection extending therefrom, whereby the projection prevents an operator positioning the end of the handle in his/her palm. The operator is therefore forced to wrap his/her hand around the handle such that the fingers are wrapped therearound and are 20 protected during the sharpening process. The handle end may have a hook secured thereto so the tool may be hung on a hook. The sharpening tool may also comprise a guard located between the handle and the guide whereby the guard is adapted to protect the operators hand from the 25 cutting edge when sharpening. The guard may extend radially from the longitudinal axis of the tool such that it extends further than both the handle and guide. 4 The sharpening tool may be adapted for easy cleaning as well as minimising areas where contaminants are able to build up. In another aspect of the invention the guide is located at a distal end of the rod remote from the handle. With this arrangement those operators who move the 5 knife in an upward direction can still gain the benefits of the present invention The present invention further provides a sharpening tool comprising an elongate element of circular cross section and having a surface to facilitate the sharpening of a blade with the joint axial and transverse movement of the blade over the surface of the elongate element, a handle fixed to one end of the elongate 10 element, at least one end of the elongate element having a guide of conical configuration permanently fixed to the elongate element, the conical surface of the guide being at an angle relative to the longitudinal axis of the surface of the elongate element which corresponds to the desired sharpening angle of the blade relative to the surface of the elongate element. 15 The guide may be formed integrally on the elongate element and is formed of the same material as the elongate element. In one aspect of the invention the guide is provided at the opposite end of the elongate element to the handle. In one aspect of the invention the guide is formed integral with the elongate 20 element. In another aspect of the invention the guide is formed as a separate element to the elongate element and then bonded to the elongate element. The guide may formed of a plastics material. The guide may be formed as part of the handle. 5 Brief Description of the Drawings The present invention will be farther explained with reference to several specific embodiments of the invention as shown in the attached drawings. The drawings shown are not necessarily to scale, with emphasis instead generally being placed 5 upon illustrating the principles of the present invention. Figure 1 is a perspective view of a sharpening tool according to a first embodiment; Figure 2 is a side view of the sharpening tool shown in figure 1; Figure 3 are various sectional views of the sharpening tool shown in figure 10 2; Figure 4 is a perspective view of a sharpening tool according to a second embodiment; Figure 5 is a side view of the sharpening tool shown in figure 4; Figure 6 is a left hand end view of the sharpening tool shown in figure 4; 15 Figure 7 is a right hand end view of the sharpening tool shown in figure 4; Figure 8 is a side elevation of a sharpening tool according to a third embodiment; Figure 9 is a schematic illustration of the sharpening action for a blade utilising the sharpening tool according to the third embodiment; and 20 Figure 10 is an isometric view of a sharpening tool according to a fourth embodiment.. 6 Best Mode(s) for Carrying out the Invention Sharpening tools for sharpening the cuffing edge of a cutting instrument such as a knife are well known. However, the present invention provides a sharpening tool which addresses known problems of the prior art by combining numerous unique 5 features into the one tool. The embodiments of the invention as shown in the attached figures 1 to 7 comprise a sharpening tool 11. The sharpening tool 11 comprises a handle 13 which may be gripped by an operator, a rod 15 and a guide 17 located between the rod and the handle. 10 An end 14 of the handle has a ring 23 secured thereto to assist with storing the tool. The ring 23 also has the effect of preventing operators from using the palm of their handle to support the tool, but rather encourages them to wrap their palm and fingers around the handle thus ensuring fingers are away from the cutting edge during the sharpening process. 15 The sharpening tool 11 also comprises a guard 21 located between the guide and the handle. This serves to further protect the operator's hand. The guard 21 extends radially outwardly further than the handle or guide. The guide has a guide face 19 which is angled relative to the rod so as to provide an optimum angle for the cutting edge of the knife. 20 The guide face 19 is knurled (not shown) such that the knife is less likely to slip when being positioned on the guide face and during the initial stages of the sharpening process. The knurled effect is created by engraving a series of coaxial rings on the guide face. Obviously the guide face 19 may be etched or otherwise engraved to provide a similar effect. Such treatments are considered to 25 be within the scope of this application. The rod 15 is etched and lined (not shown) whereby lines extend along the length of the rod in the longitudinal direction. These features assist in realigning the microscopic teeth of the cutting edge during the sharpening process as well as 7 maintaining a degree of traction between the rod and the knife during the sharpening process. In the second embodiment as shown in figures 4 to 7 like features to those in the first embodiment are referred to by like numerals. The second embodiment of the 5 invention differs from the first embodiment in that the guide 17 is spaced a distance from the guard 23. This is to allow the tool to be used to sharpen wide blades. As the guard 23 is offset from the guide 17, the operator is still able to obtain the correct angle of the knife without the knife blade interfering with the guard. 10 Referring to figures 8 and 9, the sharpening tool 11 according to a third embodiment comprises a handle 111 and a sharpening steel 113 which is elongate in configuration, of circular cross section throughout its length and extends axially from the handle. The sharpening steel 113 is formed of a material and/or the surface is treated to provide a surface which will facilitate the 15 sharpening of a blade when a blade is caused to pass over the surface. The handle is associated with a guard 115 which is located at the inner end of the handle 111 adjacent the sharpening steel. In addition the sharpening tool according to the embodiment comprises a guide element 119 which is received over the elongate element which is located on the elongate element adjacent the 20 guide 115. The guide 119 is formed integrally with the sharpening steel 113 and is thus formed of the same material as the sharpening steel. The guide is of a frusto conical configuration and the conical surface of the guide 119 is set at an angle which effectively realigns the edge of the knife to maintain sharpness when it is 25 caused to pass over the surface of the elongate element 113. In use (and as shown at Figure 9) at the commencement of the sharpening step the blade is located on the guide 119 such that it overlies the conical face of the guide and is thus set at the desired angle to the elongate element to effect proper sharpening. The blade is then caused to move over the blade both longitudinally 8 and transversely to effect the desired sharpening of the blade. This process is repeated for each stroke of the blade as required. The embodiment provides a means whereby the user is able to adopt the correct angle of the blade relative to the elongate element prior to each stroke and as a 5 result is more likely able to maintain the correct angle throughout the stroke. A fourth embodiment of the invention is shown at Figure 10 and differs from the third embodiment in that in the fourth embodiment the guide 119 is located at the end of the sharpening steel 113 which is remote to the handle 111. The guide of the fourth embodiment is formed as an integral part of the sharpening steel. This 10 embodiment serves to provide for those persons who have the practice of sharpening their knives by movement of the blade towards the handle. According to an alternative embodiment of the invention the guide 119 is formed as a separate element which is received over the sharpening steel and which is permanently bonded to sharpening steel. According to a form of the embodiment 15 the guide is formed of a plastics material. Whilst in preferred embodiments it is formed from steel. According to an alternative embodiment the guide is formed as an integral part of the handle Construction of the sharpening tool ensures the tool is easy to clean as well as 20 ensuring food stuff does not build up on the tool. Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention. Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to 25 imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. 9

Claims (20)

1. A sharpening tool comprising a handle, a rod and a guide located at an interim position between the handle and an end of the rod, the guide providing a guide face, the guide face being at an angle relative to the rod 5 whereby the angle is such that a knife positioned first on the guide is presented to the rod at the optimum angle for sharpening.

2. The sharpening tool according to claim 1 wherein the guide face is treated so as to provide traction when a knife blade engages the guide face.

3. The sharpening tool according to claim 2 wherein the guide face is knurled 10 whereby a plurality of spaced coaxial rings is engraved on the guide face.

4. The sharpening tool according to claim 3 wherein the rings are four to two microns in radial height.

5. The sharpening tool according to any one of claims 1 to 4 wherein the guide is spaced a distance from the handle to allow for wider knife blades to be 15 correctly positioned.

6. The sharpening tool according to any one of claims 1 to 5 wherein the rod is adapted such that the grinding effect upon the cutting edge is minimal.

7. The sharpening tool according to claim 6 wherein the rod is etched.

8. The sharpening tool according to claim 6 or 7 wherein the rod has a plurality 20 of lines incorporated in or on the surface, the lines being parallel with the longitudinal axis of the rod.

9. The sharpening tool according to claim 6 wherein the rod is etched and has a plurality of lines incorporated in or on the surface.

10.The sharpening tool according to any one of the preceding claims wherein an 25 end of the handle remote from the guide has a projection extending therefrom, 10 whereby the projection prevents an operator positioning the end of the handle in his/her palm.

11.The sharpening tool according to any one of the preceding claims wherein the handle end has a ring secured thereto so the tool may be hung on a hook. 5

12.The sharpening tool according to any one of the preceding claims also comprising a guard located between the handle and the guide whereby the guard is adapted to protect the operators hand from the cutting edge when sharpening.

13. The sharpening tool according to claim 12 wherein the guard extends radially 10 from the longitudinal axis of the tool such that it extends further than both the handle and guide.

14. The sharpening tool according to any one of the preceding claims wherein the guide is located at a distal end of the rod remote from the handle.

15.A sharpening tool comprising an elongate element of circular cross section 15 and having a surface to facilitate the sharpening of a blade with the joint axial and transverse movement of the blade over the surface of the elongate element, a handle fixed to one end of the elongate element, at least one end of the elongate element having a guide of conical configuration permanently fixed to the elongate element, the conical surface of the guide being at an 20 angle relative to the longitudinal axis of the surface of the elongate element which corresponds to the desired sharpening angle of the blade relative to the surface of the elongate element.

16.The sharpening tool according to claim 15 wherein the guide is formed integrally on the elongate element and is formed of the same material as the 25 elongate element.

17. The sharpening tool according to claim 15 or 16 wherein the guide is provided at the opposite end of the elongate element to the handle. 11

18.The sharpening tool according to claim 15 wherein the guide is formed as a separate element to the elongate element and then bonded to the elongate element.

19.The sharpening tool according to any one of the preceding claims wherein the 5 guide is formed as part of the handle.

20.A sharpening tool as substantially herein described with reference to the drawings. 12