GB2470119A

GB2470119A - Knife blade

Info

Publication number: GB2470119A
Application number: GB1007503A
Authority: GB
Inventors: Stuart Carney
Original assignee: POINTLESS KNIVES Ltd
Current assignee: POINTLESS KNIVES Ltd
Priority date: 2009-05-05
Filing date: 2010-05-05
Publication date: 2010-11-10
Also published as: GB201007503D0; GB0907700D0

Abstract

A blade 2 comprises an edge 4, an end 5 and a spine 6 wherein, when the spine is viewed such that it eclipses the edge, the spine exhibits a profile that, at least in part, increases in width in the direction of the blade end 5. A section of the profile is preferably triangular or diamond shaped, and the distance between the edge and the spine may, at least in part, increase in the direction of the blade end. When the spine and the edge are viewed at 90 degrees from their mutual plane, the spine preferably exhibits a portion of concave curvature and a portion of convex curvature, and the blade edge is preferably flat.Also disclosed are the following:A blade comprising an edge, an end and a spine wherein the distance between the edge and the spine at least in part increases in the direction of the blade end;A blade comprising an edge, an end and a spine, wherein, when viewed at 90 degrees from a plane containing the spine and the edge, the end is substantially flat.

Description

Knife and knife blade The present invention aims to provide a knife and knife blade having a reduced capacity to stab or pierce.

Prior art knives generally comprise a handle and a blade, wherein the blade comprises a blade edge, a blade point (or blade end) and a blade spine. The blade edge is the cutting surface of the knife and generally extends from the blade point (or blade end) to close to the handle. The blade point (or blade end) is the part of the knife most distant from the handle and is generally used for piercing. The blade spine is the upper, thicker S...

*: part of the blade.

S..... * S

: ** 10 Presently the UK and other countries are experiencing a high level of knife-S...

:. related crime such as stabbings, many of which are grievous or fatal. Many of the knives *: used in such crimes are obtained from the domestic environment, for example household kitchen knives and cutlery, although use of commercial kitchen knives has also been known. Such knives are readily available and can cause massive injury due to their sharp points and long blades. There is therefore a need for improvements to domestic and kitchen knives to reduce their ability to cause grievous or fatal stab wounds.

According to a first aspect of the invention, there is provided a blade comprising a blade edge, a blade end and a blade spine, wherein when the blade spine is viewed such that the blade spine eclipses the blade edge, the blade spine exhibits a profile which at least in part increases in width in the direction of the blade end.

According to a second aspect of the invention, there is provided a blade comprising a blade edge, a blade end and a blade spine, wherein the distance between the blade edge and the blade spine at least in part increases in the direction of the blade end.

According to a third aspect of the invention, there is provided a blade comprising a blade edge, a blade end and a blade spine, wherein when the blade spine and the blade edge are viewed at 90 degrees from their mutual plane, the blade spine exhibits at least a portion of concave curvature.

According to a fourth aspect of the invention, there is provided a blade comprising a blade edge, a blade end and a blade spine, wherein when viewed at 90 * ***** * 10 degrees from a plane containing both the blade spine and the blade edge, the blade end is substantially flat.

*: * According to a fifth aspect of the invention, there is provided a blade comprising * any combination of the features described in the first to fourth embodiments. *

According to a sixth aspect of the invention, there is provided a knife comprising the blade of any preceding embodiment.

According to a seventh aspect of the invention, there is provided the use of a knife or blade according to any preceding embodiment to cut food.

Knives and knife blades according to the present invention reduce the risk of stabbing injuries. This is because when the blade end is pushed against a person's skin, the skin is not pierced but is instead at most only bruised. Without wishing to be bound by theory, it is believed that this prevention of skin piercing (and consequent stabbing) is due to an increase in the surface area of the blade end and/or blade spine, such that the blade end cannot pierce the skin without the exertion of a greater force than is achievable by human hands alone. This effect is seen in a wide variety of knife types, although it may be the case that decreases in knife blade size require a comparative increase in surface area of theblade end and/or the blade spine to maintain effective stab prevention.

It is to be noted that knives and blades according to the present invention do not have reduced cutting ability since the blade edge is unaffected.

When considering in detail the first aspect of the present invention, the blade * : *: 10 spine preferably exhibits a maximum width. This maximum width can be achieved by virtue of a section of the profile being substantially triangular or diamond-shaped. It is **** * preferable that the maximum width occurs within 5 cm of the blade end, more preferably * within 3cm, most preferably within 1cm or at the blade end itself. The maximum width * can decrease before the blade end is reached. Preferably the increase in width of the blade spine begins at a distance from the end of approximately 20% of the total blade length.

When considering the third aspect, the blade spine preferably also exhibits at least a portion of convex curvature. Preferably the curvature of the blade spine, when starting adjacent to the blade end and moving in a direction away from the blade end, is convex, followed by concave, followed by flat. Preferably the blade edge exhibits at least a portion of convex curvature.

Preferably the blade is flat ground from the blade edge to the blade spine, such that the cross section of the blade is substantially triangular. Preferably the cross section at the blade end is an isosceles triangle, with only 2 sides equal in length. Preferably the two long sides of the isosceles triangle are at least 5 times the length of the shortest side, more preferably at least 10 times, most preferably at least 15 times.

When considering the fourth aspect, preferably the blade end does not comprise a point.

When considering the sixth aspect, preferably the knife or blade is suitable for S..

kitchen use or suitable for cutlery use. Preferably the knife or blade is unsuitable for * 10 stabbing and/or piercing. * S. * S S **5*

When considering the seventh aspect, it is preferable that the knife or blade is *: used to facilitate the preparation or eating of food. Suitable food includes raw or cooked items such as fish, meat, vegetables, fruit, nuts, seeds, etc. The invention will now be illustrated by reference to the following figures: Figure 1 is a side view of a knife according to the present invention.

Figure 2 is a top view of a knife according to the present invention.

Figure 3 is an end-on view of the blade as shown in Figures 1 and 2.

As can be seen from Figure 1, a knife 1 has a handle 2 and a blade 3. The blade 3 has a blade edge 4, a blade end 5 and a blade spine 6. When the blade spine 6 and the blade edge 4 are viewed at 90 degrees from their mutual plane (as shown in the figure), the blade edge 4 is convex. When viewed in the same manner, the blade spine 6 is convex where it meets the blade end S and changes to concave as the distance from the blade end 5 increases. Thereafter there is no curvature, i.e. the curvature of the blade spine 6 is flat as the handle 2 is approached. In the case of the knife 1 shown, this arrangement gives rise to the distance between the blade edge 4 and the blade spine 6 increasing in the direction of the blade end 5 for part of the blade length, since the distance between the blade edge 4 and the blade spine 6 at B-B is greater than that at A-A. The blade end 5 is flat and does not comprise a point. * *

Figure 2 shows the same knife 1 as viewed from the top. The blade spine 6 : * eclipses the blade edge (not shown), and exhibits a profile which increases in width ***.

towards the blade end. This profile is substantially triangular in the vicinity of the blade end 5. Specifically, the blade spine 6 exhibits a maximum width slightly before the blade * * end 5 is reached. This maximum width then decreases slightly as the corners are rounded to flow into the blade end 5.

Figure 3 shows the blade 3 as viewed from the blade end 5. The blade 3 is flat ground from the blade edge 4 to the blade spine 6, resulting in a blade 3 having a cross section at the blade end that is an isosceles triangle.

Claims

Claims 1. A blade comprising a blade edge, a blade end and a blade spine, wherein when the blade spine is viewed such that the blade spine eclipses the blade edge, the blade spine exhibits a profile which at least in part increases in width in the direction of the blade end.
2. A blade according to claim 1, wherein the blade spine exhibits a maximum width.
3. A blade according to either of claims 1 or 2, wherein a section of the * . * : * profile is substantially triangular or diamond shaped.: *" 10
4. A blade according to any preceding claim, wherein the distance between S...the blade edge and the blade spine at least in part increases in the direction of the blade *:*. end.

S *SS
5. A blade according to any preceding claim, wherein when the blade spine and the blade edge are viewed at 90 degrees from their mutual plane, the blade spine exhibits at least a portion of concave curvature.
6. A blade according to any preceding claim, wherein when viewed at 90 degrees from a plane containing both the blade spine and blade edge, the blade edge is substantially flat.
7. A blade comprising a blade edge, a blade end and a blade spine, wherein the distance between the blade edge and the blade spine at least in part increases in the direction of the blade end.
8. A blade comprising a blade edge, a blade end and a blade spine, wherein when the blade spine and the blade edge are viewed at 90 degrees from their mutual plane, the blade spine exhibits at least a portion of concave curvature.
9. A blade according to either of claims 5 or 8, wherein the blade spine also exhibits at least a portion of convex curvature. *... * *
10. A blade comprising a blade edge, a blade end and a blade spine, wherein : 10 when viewed at 90 degrees from a plane containing both the blade spine and the blade S..edge, the blade end is substantially flat.

* :1..
ii. A blade according to either of claims 6 or 10, wherein the blade end does * not comprise a point.
12. A knife comprising the blade of any preceding claim.
13. Use of a knife or blade according to any preceding claim to cut food.
14. Use according to claim 12, wherein the knife is used for domestic kitchen or cutlery food cutting.