GB2380464A

GB2380464A - Can opener

Info

Publication number: GB2380464A
Application number: GB0123997A
Authority: GB
Inventors: So Shun
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-10-05
Filing date: 2001-10-05
Publication date: 2003-04-09
Anticipated expiration: 2021-10-05
Also published as: GB0209759D0; GB2380465A; GB0123997D0; GB2380464B; GB2380465B

Abstract

A can opener includes first and second operating elements (1,3), each with respective handle members (2,4), pivotally connected intermediate their ends. Movement of the handles (2,4) relative each other moves a traction wheel (8) mounted on one element(3) and a cutter blade (6) mounted on the other element (1) between an inoperative position and an operative position. A can opener stabiliser (10) mounted on one element (3) has a spring loaded head (14) movable between first and second limits depending on the geometry of the end of the can to be opened. A can opener adjuster (24) is movable between an inactive position and an active position in which a convex portion (26) engages a stop (22) to limit movement of the traction wheel and cutter blade to a second operative position. A measuring device having a notch for location over a rim of the can is provided to determine whether the adjuster (24) should be moved to the active position depending on the thickness of the rim.

Description

CAN OPENER The invention relates to a manually operable can opener that has a rotatable traction wheel and a rotatable cutter blade for engagement with a metal can in order to cut open the can.

BACKGROUND OF THE INVENTION Manually operable can openers have been known for many years and may be broadly categorised into three types: a first type having a cutter blade that cuts directly into the top wall, or end, of a can, a second type having a cutter blade which cuts into the side wall of the can below the rim, and a third type having a cutter blade which cuts partially into the rim of the can.

The second and third types can be collectively referred to as laterally-cutting types, which are used to remove the end of a can at or below the can rim. Applicant's earlier patents GB 2334939 and GB 2341378, and corresponding US patent 6,058, 613, the contents of which are considered included as if explicitly set forth herein, describe a can opener that falls into this laterally-cutting type category.

Such can openers a-re advantageous but still present a number disadvantageous. One disadvantage is stability in holding the can opener in its laterally perpendicular

orientation to the can while turning the handle engaging the traction wheel. Instability and movement can affect the cutting action, resulting in a rough cut edge and/or lose metal cuttings, and comfort for the user.

A second disadvantage is that in known can openers the operative distance between the traction wheel and cutter blade is fixed, whereas the rim thickness on cans varies between can size and manufacture. A can rim can have five or more layers and a rim cutting opener, the third type, need only cut the outer layer for the can end to be removed. On thicker cans the cutter blade will cut more than one layer, which can also result in a rough cut edge and/or lose metal cuttings.

Additionally, because the cutter blade is embedded more deeply while opening thick rim cans it is more difficult to turn the manual operating handle. Can openers of this type are typically designed so that the cutter blade "bites" into the cut as the manual operating handle is turned. This worsens the problem.

It is an object of the present invention to overcome or ameliorate such problems, or at least to provide the public with a useful alternative.

SUMMARY OF THE INVENTION According to a first aspect of the invention there is provided a can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, and a stabiliser disposed on one of said elements so that in the operative position it bears against the end of the can to be opened, and wherein the stabiliser is movable between at least a first position and a second position depending on the end of the can to be opened.

Preferably, the stabiliser is movable to intermediate positions between the first and second positions.

Preferably, the stabiliser is a pin slidably disposed within an aperture in the one element.

Preferably, the pin has a head member at its first end and a foot member at its second end to retain it within the aperture and a biasing spring to hold it in the first position, the pin being movable to the second and intermediate positions against the bias of the spring.

Preferably, the aperture in the one member has a bushing, the pin being slidaoly disposed within the bushing.

According to a second aspect of the invention there is provided a can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, and an adjuster movable between an inactive position and an active position wherein in the active position movement of the handles relative each other moves the traction wheel and cutter blade between the inoperative

position and a second operative position.

Preferably, in the active position the adjuster restricts movement of the handles relative each other.

Preferably, the adjuster includes an elongate member pivotally disposed on one element wherein in the inactive position the longitudinal axis of the elongate member is parallel to the longitudinal axis of the one element and in the active position the longitudinal axis of the elongate member is perpendicular to the longitudinal axis of the one element such that during movement of the handles relative each other the elongate member engages the other element.

Preferably, a stop is disposed on the other element, the elongate member being adapted to engage the stop.

Preferably, the can opener further including a measurer operable in use to indicate whether the adjuster should be set in the inactive or active position.

Preferably, the measurer includes a notcn dimensioned to locate over the rim of a can to be opened with the adjuster in the inactive position, wherein if the notch cannot locate over the rim of the can to be opened the adjuster is moved to the active position.

Preferably, the measurer is located on a member slidably disposed within one handle and movable from a concealed position to an operable position for use.

Preferably, the cutter wheel is adapted and arranged to cut substantially only the outer radial layer of a can rim.

According to a third aspect of the invention there is provided a can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, a stabiliser disposed on one of said elements so that at least in the operating position it bears against the end of the can to be opened, and wherein the stabiliser is movable between at least a first position

and a second position depending on the end of the can to be opened, and an adjuster movable between an inactive position and an active position wherein in the active position movement of the handles relative each other moves the traction wheel and cutter blade between the inoperative position and a second operative position.

Further aspects of the invention will become apparent from the following description which is given by way of example only.

BRIEF DESCRIPTION OF DRAWINGS Embodiments of the invention will now be more particularly described, by. way of example only, with reference to the accompanying drawings, in which: Figure 1 is a first bottom perspective view of one embodiment of a can opener according to the invention, Figure 2 is a second bottom perspective view of the can opener in Figure 1, Figure 3 is a perspective view of a can opener stabiliser according to the invention,

Figure 4 is a first side illustration of the stabiliser, Figure 5 is a second side illustration of the stabiliser, Figure 6 illustrates stabiliser operation on a first can type, Figure 7 illustrates stabiliser operation on a second can type, Figure 8 illustrates stabiliser operation on a third can type, Figure 9 illustrates a desired cutting result from a can opener according to the invention, Figure 10 illustrates an undesirable cutting result, Figure 11 illustrates a first adjuster according to the invention, Figure 12 shows the adjuster of Figure 11 in more detail, Figure 13 illustrates a second adjuster according to the invention,

Figure 14 illustrates a third adjuster according to the invention, and Figure 15 illustrates a can rim measurer according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring firstly to Figures 1 and 2 of the drawings, there shown is a can opener comprising a first operating element 1 extending to a first handle member 2 and a second operating element 3 extending to a second handle member 4. The first and second elements 1 and 3 are pivotally connected together intermediate their ends by a pivot pin 5. Pivotally opposite first handle 2 first element 1 bears a cutter mechanism 6 having a cutter blade 7. Pivotally opposite second handle 4 second element 3 bears a traction wheel 8. The arrangement is such that pivotal movement of handles 2 and 4 relative each other varies the distance between cutter blade 7 and traction wheel 8 from an operative position, shown in Figure l, to an inoperative position, shown in Figure 2.

An operating handle 9 is axially connected to traction wheel 8 and operable to rotate traction wheel 8.

In use the rim of a can to be opened (not shown) is located between the traction wheel 8 and cutter blade 7,

and the handle members 2 and 4 brought together, as in Figure 1, to move the traction wheel 8 and cutter blade 7 to the operative position. Traction wheel 8 engages the inner radial surface of the can rim and the cutter blade 7 engages the outer radial surface of the can rim. The operating handle 9 is rotated, turned, to rotate the traction wheel. This causes the rim to move and the cutter blade 7 to cut through at least the outer radial surface of the can. The operating handle is turned so that the can to be opened rotates through 360 and the entire circumference of the outer radial surface of the rim is cut by the cutter blade. The can end can be removed from the can.

A can opener according to the above description is more fully described in Applicant's United Kingdom patent numbers GB 2334939 and GB 2341378, and corresponding United Stated patent number US 6,058, 613.

The can opener has a stabiliser 10 at the distal end of second element 3. In use stabiliser 10 rests on the end of the can during opening. This stabilises the can opener and results in greater comfort for the user and a cleaner cut.

Figure 3 shows an enlarged view of the stabiliser 10 on element 3. One uniqueness of the present invention is

that the stabiliser 10 is adjustable to suit a variety of can sizes and makes. Figure 4 shows a detailed view of the stabiliser 10 in its first or extended position and Figure 5 shows a detailed view of the stabiliser 10 in its second or compressed position.

The stabiliser 10 comprises an elongate shaft 11 disposed within an aperture 12 in element 3. At the proximal end of shaft 11 is a flange or foot 13 and at the distal end of shaft 11 is a rounded head member 14. Aperture 12 and shaft 11 are dramatically smaller than head 14 and foot 13 so that shaft 11 cannot be withdrawn from aperture 12.

A spring 15 is located about shaft 11 and between head 14 and a guide or bushing 16 in juxtaposition the aperture 12. The spring biases stabiliser 10 in the extended position as shown in Figure 4. In the compressed, or retracted, position shown in Figure 5 head 14 is flat against element 3 and spring 15 is compressed within bushing 16.

Figures 6 to 8 show the benefit of the stabiliser in supporting the can opener on cans having different end configurations.

Figure 6 shows a can where rim 17 does not protrude very far above can end surface 18. This could be termed a

shallow end can. In use the stabiliser is compressed to near its maximum extent.

Figure 7 shows a can where the rim 17 protrudes further above the can end surface 18. The can end is deeper than Figure 6 and the stabiliser is about half compressed.

Figure 8 shows a can where the end surface has a concave shape. This causes a deep can end and the stabiliser is near its maximum extended position. Furthermore, because of the concave shape the end of the can is not flat.

Head 14 has a rounded mushroom shape allowing it to sit on the inclined surface of can end 18.

The Applicant envisages that the stabiliser 10 will have a travel between compressed and extended positions of about 4 mm if it is to suit most common can types.

However, such is not critical to the invention and the travel may vary within practical limits.

By having a stabiliser that is adjustable to can end depth the can opener can be held firmly in the lateralcutting position regardless of can end depth. This results is a cleaner cut and more comfortable operation.

Referring to Figure 9, shown in A is the cutting action

of the can opener. In the operative position, e. g.

Figure 1, traction wheel 8 bears against the inner radial surface 19 of rim 17 and cutter blade 7 bears against outer radial surface 20. B shows a section through rim 17 where it can be seen that there are, for example, five layers of tin. In the preferred embodiment the'can opener only cuts the layer of the outer radial surface 20.

The rim 17 of cans can vary between manufactures and depending on can size. The variation relates mainly to the thickness (width) of the rim between the inner radial surface 19 and the outer radial surface 20. Because the operative position of the traction wheel 8 and cutter blade 7 in known can openers is fixed the opener will cut more than one outer layer in thick rim cans. This is illustrated in Figure 10. This can result in metal cuttings similar to swarf which might contaminate the can contents. The area of problem is indicated by numeral 21 in Figure 10. Furthermore, because the cutter blade 7 is embedded more deeply into a thick can rim 17 it is more difficult to turn the manual operating handle 9.

Another uniqueness of the current invention is an adjuster that varies the operative distance between the traction wheel 8 and cutter blade 7 in the operative position.

Figure 11 and 12 illustrate a preferred embodiment of the adjuster. From Figure 1 it can be seen that handle members 2 and 4 are planer elements bend in substantially a"U"shaped cross-section to provide comfortable gripping members. The inside edge of the handle members, the top part of the"U"profile, is open. Disposed within one of the handle members, say 4, is a stop member 22. The surface of the stop member 22 that is open to the inner part of handle 4 has a, concave portion 23.

Pivotally disposed within the second handle 2 is an elongate member such as arm 24. The proximal end of arm 24 is pivotally engaged to handle 2 at a pivot point 25.

At the distal end of arm 24 is convex portion 26.

Extending perpendicular to arm 24 is a lever 11, which extends to a position clear of the open side of the handle 2.

Referring to Figure 12, in the inactive position E arm 24 is oriented parallel to the longitudinal axis of handle 2 and lever 11 extends perpendicular to handle 2 where it is accessible to a user. In this position the can opener can be moved to the operative position, as shown in Figure 1, to provide a distance between traction wheel 8 and cutter blade 7 of Y.

For tin cans with thicker (wider) rims 17 the adjuster can be moved to the active position F. While the can opener is still in the inoperative position, shown in Figure 2, lever 11 is"flipped"to pivot arm 24 to an active position perpendicular with handle 2. In use, before the can opener can be closed to the full operative position convex end 26 of arm 24 engages concave surface 23 of stop 22. This restricts relative movement of handles 2 and 4 providing a second operative position in which the distance between the traction wheel 8 and cutter blade 7 is X. X is greater than Y. The can opener can now be used on cans with thicker rims while only cutting the outer radial layer.

Figures 13 and 14 illustrate alternative embodiments of the adjuster. In the embodiment in Figure 13. arm 24 is slidably engaged with handle 2. In the active position F lever 11 is slidably moved to allow convex end 26 to engage concave surface 23 when the can opener is closed to the second operative position.

In Figure 14 the alternative embodiment includes an elongate member 27 having longitudinal length greater than lateral width. The member is pivotally disposed on element 3 adjacent element 1. A handle 28 is axially connected to member 27 and operable to rotate member 27 from an active position to an inactive position. A notch

29 is disposed in element 1 adjacent the location of member 27. In the inactive position the member 27 is pivoted to be longitudinal parallel to elements 1 and 3.

This allows the can opener to be closed to the operative position as shown in Figure 1. To activate the adjuster the member 27 is rotated, via handle 28, to be perpendicular to the longitudinal axis of the elements 1 and 3. As the can opener is closed the member 27 engages notch 29 in element 1 restricting the degree of closure so that the can opener is in the second operative position for thicker rimed cans.

One problem for the user is deciding when the adjuster should be activated so as to utilise the second operative position. To solve this problem a measuring gauge is disposed in the handle of one embodiment. This is illustrated in Figure 15. A slidably engaged measuring member 30 is disposed within the distal end of one of the handle members 2 or 4. In the illustrated embodiment it is 4. The measuring member has an extending/retracting level 31 extending through an elongate aperture 32 in the handle 4. Level 31 allows the user to extend the measuring member 30 for use and retract it when not required.

The measuring member 30 has two notches 33 and 34 in it.

One notch, a measurer 33, is dimensioned to fit over a

narrow can rim that can be cut with the can opener in the operative position shown in Figure 1. Thicker can rims, which require the activation of the adjuster to achieve the second operative position, will not fit in the measurer notch 33.

It will be apparent to the skilled addressee that measurer notch 33 is all that needed to test a can rim to determine if the adjuster should be activated. Noncritical to this aspect of the invention is second notch 34 which is wider than notch 33. If the rim of the can cannot fit within second notch 34 then it is too big for the can opener.

In alternative embodiments the sliding member 30 is omitted and the measurer notch 33, and optionally second notch 34, are in the end, or otherwise, of the handle.

This reduces the number of mechanical parts in the can opener.

Embodiments of the invention have been given by way of example only, and various other modifications of and/or alterations to the described embodiments may be made by persons skilled in the art without departing from the scope of the invention as specified in the appended claims.

Claims

CLAIMS 1. A can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, and a stabiliser disposed on one of said elements so that in the operative position it bears against the end of the can to be opened, and wherein the stabiliser is movable between at least a first position and a second position depending on the end of the can to be opened.
2. A can opener as claimed in claim 1 wherein the stabiliser is movable to intermediate positions between the first and second positions.
3. A can opener as claimed iD claims 1 or 2 wherein the stabiliser is a pin slidably disposed within an aperture in the one element.

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4. A can opener as claimed in any preceding claim wherein the pin has a head member at its first end and a foot member at its second end to retain it within the aperture and a biasing spring to hold it in the first position, the pin being movable to the second and intermediate positions against the bias of the spring.
5. A can opener as claimed in any preceding claim wherein the aperture in the one member has a bushing, the pin being slidably disposed within the bushing.
6. A can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted. on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, and an adjuster movable between an inactive position and an active position wherein in the active position

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movement of tne handles relative each other moves the traction wheel and cutter blade between the inoperative position and a second operative position.
7. A can opener as herein described with reference to the accompanying drawings.

7. A can opener as claimed in claim 6 wherein in the active position the adjuster restricts movement of the handles relative each other.

8. A can opener as claimed in claims 6 or 7 wherein the adjuster includes an elongate member pivotally disposed on one element wherein in the inactive position the longitudinal axis of the elongate member is parallel to the longitudinal axis of the one element and in the active position the longitudinal axis of the elongate member is perpendicular to the longitudinal axis of the one element such that during movement of the handles relative each other the elongate member engages the other element.

9. A can opener as claimed in claim 8 wherein a stop is disposed on the other element, the elongate member being adapted to engage the stop.

10. A can opener as claimed in any one of claims 6 to 9 further including a measurer operable in use to indicate whether the adjuster should be set in the inactive or active position.

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11. A can opener as claimed in claim 10 wherein the measurer includes a notch dimensioned to locate over the rim of a can to be opened with the adjuster in the inactive position, wherein if the notch cannot locate over the rim of the can to be opened the adjuster is moved to the active position.

12. A can opener as claimed in claims 10 or 11 wherein the measurer is located on a member slidably disposed within one handle and movably from a concealed position to an operable position for use.

13. A can opener as claimed in any preceding claim wherein the cutter wheel is adapted and arranged to cut substantially only the outer radial layer of a can rim.

14. A can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter

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blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can to be opened, a stabiliser disposed on one of said elements so chat at least in the operating position it bears against the end of the can to be opened, and wherein the stabiliser is movable between at least a first position and a second position depending on the end of the can to be opened, and an adjuster movable between an inactive position and an active position wherein in the active position movement of the handles relative each other moves the traction wheel and cutter blade between the inoperative position and a second operative position.

15. A can opener of the laterally-cutting type as herein described with reference to Figure 1 to
8.

16. A can opener of the laterally-cutting type as herein described with reference to Figure 1, 2 and 9 to 15.

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Amended claims have been filed as follows CLAIMS

1. A can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can, and a stabiliser disposed on one of the said elements so that in the operative position it bears against the end of the can, and wherein the stabiliser is movable between at least a first position and a second position.

2. A can opener as claimed in claim 1 wherein the stabiliser is movable to intermediate positions between the first and second positions.

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3. A can opener as claimed in claims 1 or 2 wherein the stabiliser is a pin slidably disposed within an aperture in the one element.

4. A can opener as claimed in any preceding claim wherein the pin has a head member at its first end and a foot member at its second end to retain it within the aperture and a biasing spring to hold it in the first position, the pin being movable to the second and intermediate positions against the bias of the spring.

5. A can opener as claimed in any preceding claim wherein the aperture in the one member has a bushing, the pin being slidably disposed within the bushing.

6. A can opener of the laterally-cutting type including: first and second operating elements having first and second handle members respectively, said operating elements being pivotally connected intermediate their ends, a traction wheel rotatably mounted on one of said elements and a cutter blade rotatably mounted on the other of said elements, wherein movement of said handles relative each other moves the traction wheel and cutter

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blade between an inoperative position and an operative position in which the traction wheel and cutter blade engage the end of a can. a stabiliser disposed on one of said elements so that at least in the operating position it bears against the end of the can, and wherein the stabiliser is movable between at least a first position and a second position, and an adjuster movable between an inactive position and an active position wherein in the active position movement of the handles relative each other moves the traction wheel and cutter blade between the inoperative position and a second operative position.