GB2608099A

GB2608099A - A sheath for sharpening and retaining a knife

Info

Publication number: GB2608099A
Application number: GB2106448.0A
Authority: GB
Inventors: Carr Peter; Masson Paul
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-05-06
Filing date: 2021-05-06
Publication date: 2022-12-28

Abstract

A knife sheath 2 contains sharpening elements that can be manually raised to contact the blade of a knife as it is introduced and/or removed from the sheath. The sharpening elements are connected to a flexible strip 4, such as a leaf spring, on the exterior underside of the sheath which may lie in a slot in the sheath. The sharpening elements are raised into position against pressure from the flexible strip and may be contained within a housing 3 having a slot (11 fig.3). A pin 12 may restrict the extent of movement of the housing. The sheath also has a manually releasable pivoting locking device 6 that can be activated to retain the blade of the knife within the sheath.

Description

A SHEATH FOR SHARPENING AND RETAINING A KNIFE

The present invention relates to improvements in or relating to the sharpening of knives and in particular relates to sheaths for knives that can be used for sharpening knives as they are introduced and/or withdrawn from the sheath and furthermore enables the knife to be locked within the sheath for safety and storage.

Sheaths for knives provided with sharpening elements that can be used to sharpen a knife as it introduced and/or withdrawn from the sheath are well known particularly for knives that are used in the food industry such as cooks knives, carving knives, pairing knives and bread knives. It is also known to provide sheaths that sharpen knives and can also be locked once a knife in inserted therein for safety purposes in order to avoid inadvertent removal of the knife from the sheath particularly during storage and handling.

United States Patent 6,224,475 describes one such system in which knife sharpening elements are provided at the lower side of the knife entry position of a sheath and the sharpening elements can be raised into the entry position to be in contact with the blade of the knife as it is inserted into or withdrawn from the sheath in order to sharpen the knife. The sharpening elements are raised manually by pressing a trigger against the elements; the trigger being pivoted about the remote end of the sheath.

The sheath of US 6,224,475 is also provided with a locking device for frictionally locking the knife within the sheath. The locking device comprises elements at the entrance to the sheath which frictionally grip the handle of the knife to lock it at the entrance to the sheath.

The mechanisms involving manually bringing the sharpening elements into contact with the blade while simultaneously ensuring that the knife blade and handle are appropriately positioned to ensure the frictional locking of the blade into the sheath after full insertion into the sheath are both complicated and raise safety concerns.

United States Patent 6,117,002 describes a knife sharpening sheath in which the knife can also be retained within the sheath. The sheath requires means to press the knife blade downwards into the sharpening means and furthermore requires that the sharpening means itself can be pivoted into and out of its sharpening position. Once again the system is cumbersome and is difficult to operate manually and again raises safety concerns.

The present invention addresses these issues and provides a simpler and safer knife sharpening sheath.

The present invention therefore provides a sheath for storing a knife that can also be used to sharpen the knife the sheath comprising a near end providing an opening for insertion and withdrawal of the knife the opening being provided with blade sharpening elements at its lower edge which can be raised to contact and sharpen the blade as it is inserted and/or withdrawn from the sheath wherein the sharpening elements are mounted on means that can manually raise the elements into their contact and sharpening position and wherein the sheath is provided with a manually operable releasable locking device which can be activated to retain the knife blade within the sheath once it is inserted therein and can be released to allow withdrawal of the knife from the sheath.

The sharpening elements employed in the sheath of the present invention comprise two elements which can be raised to a position where they are in contact with either side of the cutting face of the blade of the knife as it is inserted and/or withdrawn from the sheath, the elements can be returned to their lower inactive position when the knife is fully within the sheath or is removed therefrom for use. The elements may be of traditional sharpening material such as hard metals tungsten being a preferred material alternatively the elements may be ceramic. The means that can manually raise the sharpening elements is preferably a flexible strip that preferably extends at least part way along the underside exterior of the sheath away from the knife entry position. In a preferred embodiment a slot is provided in the underside of the sheath into which the strip can be pressed. The strip is connected to the sharpening elements at or close to the knife entry position so that it can readily be pressed against the underside of the sheath and preferably into the slot formed in the underside in order to raise the sharpening elements into their sharpening position at both sides of the blade of the knife. In this way the elements can be readily raised by an operator who is holding the sheath for insertion or removal of the knife from the sheath by simply pressing the strip against the underside of the sheath. In a preferred embodiment the means that raises the sharpening elements comprises a leaf spring attachable to the sheath at a position close to the open end of the sheath and attached at one end to the sharpening elements and extending at least part way along the underside exterior of the sheath from the open end thereof. In another embodiment the blade of the knife can be simultaneously pushed downwards into the sharpening elements by applying downward pressure on the knife.

It is preferred that the releasable locking device is mounted on the exterior of the sheath and close to the open entry end of the sheath. It is further preferred that it is shaped so that it can be pivotally moved to engage with the handle of the knife once the knife is fully inserted into the sheath thereby locking the knife within the sheath. The underside of the handle of the knife can be shaped to provide a recess for receipt of the locking mechanism. In this way the locking mechanism and the sharpening unit can be mounted close to each other rendering both the sharpening and the locking readily achievable manually and enabling the insertion or withdrawal of the knife from the sheath by an operator.

It will be appreciated that the invention is applicable to a wide range of knives of differing shapes and sizes and the sheath, sharpening elements and their mounting and the releasable locking device will be shaped to suit the design of the particular knife. The sheath of the knife is preferably made from a strong plastic material such as polypropylene or acrylonitrile butadiene copolymers and the mounting means carrying the sharpening element can be of a strong flexible material, a polyacetal being preferred. The invention is particularly useful with knives used in the food industry such as carvers, cooks knives, bread knives, paring knives, santoku knives and utility knives.

The present invention is illustrated by reference to the accompanying Figures in which Figure 1 shows a knife placed within a sheath according to the present invention with the releasable locking means in the open position.

Figure 2 is an expanded version of the entrance end of the sheath showing how the locking means can be moved from the open position to a locked position.

Figure 3 is a side view of the sharpening element container together with a flexible strip for raising the sharpening elements as is used with the sheath of Figure 1.

According to Figure 1 the knife comprises a handle (1) and a blade which cannot be seen because it is located within a sheath (2). A sharpening element container (3) is mounted at the open end of the sheath and is integrally formed with a flexible strip (4) extending along the underside (5) of sheath (2). The strip (4) and its integral sharpening unit can be manually pushed upwards as the knife is inserted or withdrawn from the sheath to bring the sharpening elements within the sheath (not shown in Figure 1) into contact with the blade to perform sharpening as the blade of the knife is inserted or withdrawn from the sheath.

A releasable locking means (6) is also provided at the open end of the sheath. In Figure 1 it is shown in the open position (7) allowing the blade to be inserted or withdrawn from the sheath.

The handle of the knife shown in Figure 1 has a recessed section (8) and Figure 2 which is an expanded view of the assembly at the open end of the sheath shown in Figure 1 shows how the releasable locking device can be moved from the open position (7) of Figure 1 into the locking position (9) shown in Figure 2. In the locking position the locking means bears against the recessed section (8) of the handle to lock the knife in the sheath until the locking means is returned to open position (7) to allow removal of the knife from the sheath.

Figure 3 is a side view of the sharpening element holder employed in Figure 1 which comprises a holder for the sharpening elements (not shown) (10) provided with an orifice (11) which can fit over a pin (12) provided in the external surface of the sheath of Figure 1 (see Figure 1) in a manner that allows the holder to be moved up and down on the pin. The element of Figure 3 also includes the flexible strip (4) of Figure 1 whereby upward force applied to the strip will move the holder (10) containing the sharpening elements (not shown) upwards on the pin to bring the sharpening elements into contact with the blade of the knife, when the force is removed the strip and the sharpening elements will return to their inactive position. It will be appreciated that Figure 3 is a view from just one side of the sharpening element holder and a similar view would be seen from the other side.

Claims

CLAIMS 3. 4 5 6.A sheath for a knife that can also be used to sharpen the knife the sheath comprising a near end providing an opening for insertion and withdrawal of the knife the opening being provided with blade sharpening elements at its lower edge which can be raised to contact and sharpen the blade as it is inserted and/or withdrawn from the sheath wherein the sharpening elements are mounted on means that can manually raise the elements into their contact and sharpening position and wherein the sheath is provided with a manually operable releasable locking device which can be activated to retain the knife blade within the sheath once it is inserted therein and can be released to allow withdrawal of the knife from the sheath.
A sheath according to Claim 1 comprising two sharpening elements which can be raised to a position where they are in contact with either side of the cutting face of the blade of the knife as it is inserted and/or withdrawn from the sheath.
A sheath according to Claim 2 wherein the elements are of hard metal such as tungsten or are ceramic.
A sheath according to any of the preceding claims wherein the means that can manually raise the sharpening elements is a flexible strip that extends at least part way along the exterior underside of the sheath away from the knife entry position of the sheath.
A sheath according to Claim 4 wherein the strip is connected to the sharpening elements at or close to the knife entry position so that it can be pressed against the underside of the sheath in order to raise the sharpening elements into their sharpening position at both sides of the blade of the knife.
A sheath according to Claim 4 or Claim 5 provided with a slot at its underside into which the strip can be pressed.
A sheath according to any of the preceding claims wherein the means that raises the sharpening elements comprises a leaf spring attached to the sheath at a position close to the open end of the sheath and attached to the sharpening elements at one end of the leaf spring.
8 A sheath according to any of the preceding claims wherein the releasable locking device is mounted on the exterior of the sheath and is shaped so that it can be pivotally moved to engage with the handle of the knife once the knife is fully inserted into the sheath thereby locking the knife within the sheath.
9. A kit comprising a sheath according to any of the preceding claims and a knife shaped to be inserted and withdrawn from the sheath.
10. A kit according to Claim 9 wherein the knife is selected from a cooks knife, a carving knife, a paring knife, a bread knife santoku knives and a utility knife.