Can lid lifter for can opener

Information

  • Patent Grant
  • 6671970
  • Patent Number
    6,671,970
  • Date Filed
    Tuesday, January 29, 2002
    23 years ago
  • Date Issued
    Tuesday, January 6, 2004
    21 years ago
Abstract
This invention relates to a novel can lid lifter for a hand operated can opener. More particularly, the invention is directed to a novel can lid lifter for a hand operated can opener that cuts the outer seam wall of a can, rather than the top interior lid of the can, in order to remove the lid. A can opener comprising: (a) a handle; (b) a clamping lever; (c) a hand crank; (d) a wheel cutting blade; (e) a traction wheel which rotates when the hand crank is rotated; (f) a can lid top contact member mounted on an exterior of the can opener; (g) a can lid lifting pin associated with the can lid top contact member for releasably catching the edge of a cut can lid.
Description




FIELD OF THE INVENTION




This invention relates to a novel can lid lifter for a hand operated can opener. More particularly, the invention is directed to a novel can lid lifter for a hand operated can opener that cuts the outer seam wall of a can, rather than the top interior lid of the can, in order to remove the lid.




BACKGROUND OF THE INVENTION




Can openers are well known. In general, they comprise a traction wheel and a cutting wheel. The traction wheel when rotated acts as a reaction surface against the can and drives the can opener around the lip of the can while the sharpened cutting wheel simultaneously cuts through the can. The most common commercially available type of can opener is one that cuts the top interior lid of the can to gain access to the can contents. A main problem with this type of can opening is that the cutting blade cuts down through the lid from the top circumference thereof and tends to come into contact with the contents of the can. This is a problem if the cutting blade is dirty from previous use or has harmful bacteria on the cutting blades. A further problem is that if the cutting blade is not particularly sharp, it will not cut the lid edge cleanly and will tend to form small metal shavings that fall into and contaminate the contents of the can. The metal shavings can be harmful if ingested. Yet a further problem is that if the entire circumference of the can lid is cut, the top lid is no larger and often falls into the can contents and can be difficult and messy to remove from the interior of the can. The exterior of the can which can be dirty is exposed to the can contents, which are ultimately consumed.




To overcome these problems, can openers have been developed that cut the outside seam of the can so that the lid and part of the circumferential seam are cut and removed from the can. In this way, the cutting blade does not contact the contents of the can, there are no metal shavings that fall into the interior of the can, and the can lid does not drop into the interior of the can. Examples of this design of can opener include U.S. Pat. No. 3,719,991 to French; U.S. Reissued Pat. No. 27,504 to Smith; U.S. Pat. No. 1,935,680 to Von Wolforsdorf; U.S. Pat. No. 4,782,594 to Porucznik et al. and U.S. Pat. No. 3,510,941 to Fyfe. All of these patents disclose a can including a pin sliding in an arcuate slot for engaging and locking the can opener on the can to be opened. While these arrangements work adequately, over time and use there is a tendency for the moving parts to wear with the result that the engaging and locking function of the opener is impaired thereby leading to difficulty in cutting the can and keeping the opener in position on the can.




My U.S. Pat. No. 5,121,546, granted Jun. 16, 1992, discloses an effective solution of the above problem. In the can opener design disclosed in that patent, there are thrust surfaces and a separating means that can be introduced between the thrust surfaces. The separating means, typically a ball bearing, is introduced between the thrust surfaces and moves a movable thrust surface away from a fixed thrust surface to separate a movable wheel, usually the traction wheel, and a cutting wheel. By this method, the can opener is brought to the cutting position. The wheel can then be rotated to cut the can. While the can opener disclosed in my U.S. Pat. No. 5,121,546 has proved to be extremely effective, experiments with groups of people have shown that a certain amount of manual dexterity is required in order to effectively operate the can opener. This can be a disadvantage because many persons endeavouring to open cans, such as the elderly or handicapped, do not have a great deal of manual dexterity.




My subsequent U.S. Pat. No. 5,367,776, granted Nov. 29, 1994, discloses a can opener which requires less manual dexterity in order to be operated. The can opener comprises a housing having a handle. The cutting wheel has a cutting edge for severing a can wall, the cutting wheel defining a cutting wheel axis. The opener also has a traction wheel with a gripping surface which engages the can, the traction wheel defining a traction wheel axis. The opener includes a hand crank for rotatably mounting the traction wheel and the cutting wheel in the housing such that their axes are substantially perpendicular and the wheels are positioned adjacent and spaced apart from each other to define a gap to accept the seam of the can to be opened. One of the wheels is movable towards the other in order to engage and lock the can between the cutting wheel and the traction wheel so that the cutting wheel acts to sever the can wall. The traction wheel acts to move the can past the cutting wheel. The first thrust surface is associated with the housing and the spaced, adjacent, second thrust surface is associated with the moveable wheel. The first and second thrust surfaces comprise cooperable cam surfaces which are rotatable relative to each other to reciprocate the first and the second thrust surfaces relative to each other between a first position, where the gap is relatively wide, and a second position where the gap is narrow and the can is engaged and locked between the cutting wheel and the traction wheel. A hand crank is associated with one of the wheels to permit rotation thereof.




My third U.S. Pat. No. 6,101,727, granted Aug. 15, 2000, protects a dual-handle pump-action type can opener that can be operated by either hand and which cuts the exterior wall of the seam of a can, rather than the top lip of the can. The dual-handle pump-action can opener includes: (a) a housing having a first handle; (b) a cutting wheel associated with the housing and the first handle and having a cutting edge for severing the exterior wall of the can seam; (c) a traction wheel associated with the housing and the first handle and having a gripping surface for engaging the interior wall of the can seam; and (d) a second handle which is movable towards and away from the first handle. When the second handle is initially moved towards the first handle after the can opener is installed on the seam of the can, it causes the traction wheel to contact the interior wall of the can seam and the cutting wheel to contact the exterior wall of the can seam. On subsequent reciprocal movement of the second handle towards and away from the first handle through a series of levers and gears, the traction wheel is caused to rotate in incremental steps to advance the traction wheel along the interior wall of the can seam, thereby causing the cutting wheel also to rotate and cut the exterior wall of the can seam.




A problem with these can openers is that although they are very efficient in cutting the seam of the can lid, it is nonetheless often difficult to remove the cut can lid from the can. This is because the can has food grade sealing compound between the intersections of the lid and can body which together form the seam. This sealing compound is sticky and deters removal of the lid and part of the seam after it is cut from the can.




SUMMARY OF THE INVENTION




The invention is directed to a can opener comprising: (a) a handle; (b) a clamping lever associated with the handle; (c) a hand crank associated with the clamping lever and handle; (d) a wheel cutting blade mounted on the can opener; (e) a traction wheel which rotates when the hand crank is rotated; (f) a can lid top contact member mounted on an exterior of the can opener for contacting the cut lid of a can; and (g) a can lid lifting pin associated with the can lid top contact member for releasably catching the edge of a cut can lid.




The can lid lifting pin can have a ridge thereon which can assist in catching the edge of the can lid. The lid lifting pin can be cylindrical and can have a protrusion at the distal end thereof of a diameter greater than the diameter of the cylinder. The protrusion can be in the shape of a hemisphere.




The can opener can include a “J-shaped” can abutment member associated with the wheel cutting blade and the traction wheel for assisting an operator in contacting the can opener with a can at an optimum can lid seam cutting angle. The “J-shaped” can abutment member when mounted on a can, can contact the seam of the can at an end proximate to the can opener, and at a distal end, can contact the top interior of the can lid.




The can opener can include a contact face on the wheel cutting blade which rotatably bears on the exterior underside of a seam of a can. The can wall contact face can cooperate with the “J” shaped can abutment to movably secure the can opener to the can during the can seam shearing operation.




The invention is also directed to a can opener comprising: (a) a handle; (b) a clamping lever associated with the handle; (c) a hand crank associated with the clamping lever and handle; (d) a wheel cutting blade mounted on the can opener; (e) a traction wheel which rotates when the hand crank is rotated; and (f) a “J-shaped” can abutment member associated with the wheel cutting blade and the traction wheel for assisting an operator in contacting the can opener with a can at an optimum can lid seam cutting angle.




The invention also pertains to a can lifter for use in association with a can seam cutting can opener which comprises: (a) a can lid top contact member; and (b) a can lid lifting pin associated with the can lid top contact member, the can lid lifting pin cooperating with the can lid top contact member to grip a can lid and can seam of a cut can lid.











BRIEF DESCRIPTION OF THE DRAWINGS




In drawings which illustrate specific embodiments of the invention, but which should not be construed as restricting the spirit or scope of the invention in any way:





FIG. 1

illustrates a front elevation view of the hand operated can opener with the can lifter lifting the cut lid of a can.





FIG. 2

illustrates an isometric view of the hand operated can opener equipped with the can lid lifter.





FIG. 3

illustrates a detail side elevation partial section view of the hand operated can opener shearing a cut in the top outer seam of a can.





FIG. 4

illustrates a detailed isometric partial section view of the cutting blade and traction wheel of the can opener cutting the top seam of a can.





FIG. 5

illustrates a detailed cut-away partial section view of the can lid lifter lifting a cut lid and seam from the top of a can.





FIGS. 6

to


11


illustrate bottom views of alternative designs of a can lifting pin.





FIG. 12

illustrates a top view of the can opener contacting the top seam of a can with a traction wheel, cutting wheel and J-shaped can abutment.





FIG. 13

illustrates a detailed side partial cut-away view of the can opener engaging the top seam of a can, with the J-shaped can abutment contacting the top of the can and the cutting wheel disposed at an angle to shear a cut in the top seam of the can.





FIG. 14

illustrates an end partial cut-away view of the can opener with traction wheel and J-shaped can abutment contacting the top seam and top lid of a can.





FIG. 15

illustrates a bottom isometric view of an alternative embodiment of the invention wherein the can lifter pin is a bottle cap opening hook.





FIG. 16

is an elevation view of the bottle cap opening hook.











DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION




Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.




The can opener according to the present invention utilizes some of the seam cutting components which were disclosed and illustrated in my prior U.S. Pat. No. 5,367,776, granted Nov. 29, 1994 and U.S. Pat. No. 6,101,727, granted Apr. 15, 2000. The specifications of these two patents are incorporated herein by reference. However, the invention that is disclosed and claimed herein has a number of additional features which provide advantages over the can openers that are disclosed in my prior U.S. Pat. Nos. 5,367,776 and 6,101,727.




The can opener according to the subject invention includes a can engaging clamp lever, a single finger twist handle (hand crank) and a main handle. The can opener according to the invention automatically engages the seam of the can by placing the J-shaped can abutment on the top edge of the can and depressing the can engaging clamp lever. The can opener according to the subject invention cuts the upper seam of the can on the exterior side, similar to the manner in which my prior can opener designs cut the exterior side seam of the can. However, with the present invention, the J-shaped can abutment contacts the top of the can lid and the top seam of the can on one side of the can, to align the cutting wheel, and the traction wheel and cutting wheel then proceed around the circumference of the can seam, and shear it, by having the operator turn the hand crank. The can opener according to the subject invention is disengaged from the can seam after the lid and part of the top seam of the can have been sheared by lifting the clamping lever at the top of the can opener. The can opener according to the invention, by including a J-shaped downwardly curved can abutment member, which at its distal end descends below the elevation of the can seam, and contacts the top of the can lid, assists in properly aligning the can opener on the can so that an accurate and clean shear of the can seam can be made reliably and consistently. The J-shaped can abutment member also assists in holding the can and seam in engagement with the cutting wheel and traction wheel of the can opener while it is being operated.





FIG. 1

illustrates a front elevation section view of the hand operated can opener with the can lid lifter lifting the cut lid of a can. As seen in

FIG. 1

, the can opener


2


is constructed with an ergonomically designed main handle


4


, which has grip enhancing rubber ridges


5


embedded therein. The can opener


2


includes a clamping lever


6


, a hand crank


8


, a wheel-type cutting blade


10


, a can wall contact face


17


and a semicircular can lid abutment


22


with a distal end


23


. As illustrated in

FIG. 1

, the can opener


2


according to the invention also has a lid top contact


16


and a lid lifting pin


18


located immediately below the cutting blade


10


. The lid top contact


16


contacts the top interior of the can lid


14


, adjacent the seam


13


, while the lid lifting pin


18


, which has an inverted mushroom-type protuberance, catches the underside edge of the seam


13


. The lid top contact


16


cooperates together with the lifting pin


18


to enable the operator to overcome the resistance of the sealing compound in the seam and lift the lid


14


from the can


12


. When food containing metal cans are constructed, the interiors of the can and the interiors of the lids at the top and bottom of the can are typically coated with a food grade lacquer to prevent contact of the food with the metal. In addition, a sealing compound is applied on the seams of the top and bottom lids of the can, before the top and bottom lids are stamped and affixed to the cylindrical wall of the can. This sealing compound is sticky and inhibits removal of the can lid


14


after it has been sheared from the can


12


at the top seam. The combination of the top lid contact


16


and lid lifting pin


18


enables the operator to readily catch an under edge of the top lid and assist the operator in overcoming the resistance of the sealing compound and lift the lid


14


away from the can


12


.





FIG. 2

illustrates an isometric view of the hand operated can opener equipped with the can lid lifter.

FIG. 2

is helpful in illustrating two main features of the can opener


2


, according to the invention. It illustrates how the lid top contact


16


and the lid lifting pin


18


are built as part of a can wall contact face


17


secured to the bottom of the can opener


2


immediately below the wheel cutting blade


10


.





FIG. 2

also illustrates the construction of the J-shaped can abutment


22


, with its distal end


23


, which is used to enable the operator to readily contact the top seam and top lid of the can to be cut, and properly align the traction wheel


20


and cutting wheel


10


with the seam of the can


12


.

FIG. 2

also illustrates the ergonomic design of the main handle


4


and the rubber grip ridges


5


.





FIG. 3

illustrates a detail side elevation partial section view of the hand operated can opener shearing a cut in the top outer seam of a can.

FIG. 3

is of value in illustrating how the J-shaped can abutment


22


is disposed at a critical angle and at one inner side contacts the top of the seam


13


of the can


12


, while at its opposite free end


23


, contacts the top surface of the lid


14


. In this way, when the clamping lever


6


is depressed, the traction wheel


20


and cutting blade


10


are automatically engaged at the optimum shearing angle. The can wall contact face


17


also assists in movably securing the can opener


2


in position on the can


12


. Once the traction wheel


20


and the cutting wheel


10


are in position on the can at the angle shown in

FIG. 3

, the hand crank


8


(not shown) is turned by the operator and the rotating cutting blade


10


and traction wheel


20


move around the circumference of the lid and the blade


10


shears a cut


15


in the exterior wall of the seam


13


of the can lid


14


.





FIG. 4

illustrates a detailed isometric partial section view of the cutting blade and traction wheel of the can opener cutting the top seam of a can.

FIG. 4

illustrates how the cutting wheel


10


, when it is rotated about vertical pin


24


, in combination with the turning traction wheel


20


, shears a cut


15


in the outer metal layer of the seam


13


, where the wall of the can


12


and the edge of the lid


14


are connected together in a coiled manner.

FIG. 4

also illustrates the underseam contact edge


11


on the cutting wheel. This underseam contact edge


11


rotatably contacts the underside


9


of the can seam


13


, and in cooperation with the rotating can wall contact face


19


slidably secures the cutting wheel


10


to the can


12


and seam


13


and ensures that the can


12


does not slip downwardly. The sealing compound, which is present between the folded contacting layers of the can wall


12


and lid


14


is not shown. However, it will be understood that the sealing compound is present between the connecting layers and this sealing compound deters the operator from separating the cut can lid


14


from the can wall


12


.





FIG. 5

illustrates a detailed cut away partial section view of the can lid lifter lifting a cut lid and seam from the top of a can. As seen in

FIG. 5

, the manner in which the lid top contact


16


fits snugly against the interior side of the can seam


13


, and the “inverted mushroom” end of the lid lifting pin


18


contacts and catches the underside of the exterior of the seam


13


, are illustrated in detail. Once the lid top contact


16


and lid lifting pin


18


are secured to the seam


13


of the lid


14


, leverage is provided and it is easy for the operator to lift the lid


14


from the can


12


. The edge of the lid top contact


16


that is proximate to the seam


13


is curved so that it more closely conforms with the interior curve of the seam


13


.

FIG. 5

also illustrates how the lid lifting pin


18


is conveniently machined into the bottom end of the cutting wheel shaft


24


, upon which the cutting wheel blade


10


is also mounted at the upper end (see also FIG.


4


).





FIGS. 6 through 11

illustrate bottom views of alternative designs of a can lifting pin.

FIG. 6

illustrates the most common design of the lid lifting pin


18


, which as shown in

FIG. 5

previously, is machined into the bottom end of the cutting wheel shaft


24


. The curved edge can seam conforming pattern of the lid top contact


16


is also illustrated. This curve in congruent with the interior edge of the curved seam


13


of a typical food can.

FIG. 6

also illustrates the can contact face


17


, which abuts the wall of the can


12


and assists in securing the can opener


2


, with its cutting wheel


10


and traction wheel


20


in position against the can seam


13


(not shown) for optimum shearing action of the lid


14


from the can


12


.

FIGS. 7 through 11

show alternative designs of lid lifting pins, including hexagonal


26


as seen in

FIG. 7

, semi-circular


28


as seen in

FIG. 8

, square


30


as seen in

FIG. 9

, oval


32


as seen in FIG.


10


and triangular


34


as seen in FIG.


11


.





FIG. 12

illustrates a top view of the hand operated can opener contacting the top seam of a can with a traction wheel, cutting wheel and J-shaped can abutment.

FIG. 12

is of assistance in illustrating the unique design of the J-shaped can abutment


22


, and how at its upper end


25


(as seen in

FIG. 12

) it contacts the top of seam


13


of the can, while at its lower distal end


23


, it contacts the top surface of the can lid


14


. The J-shape is advantageous because it is easy for the operator to use and quickly aligns the traction wheel


20


and cutting wheel


10


with the can


12


at the optimum can lid shearing angle (see FIG.


3


).





FIG. 13

illustrates a detailed side partial cut-away view of the hand operated can opener engaging the top seam of a can, with the cutting wheel disposed at an optimum angle to shear a cut in the top seam of the can.

FIG. 13

is helpful in that it discloses the manner in which the J-shaped can abutment


22


at the interior end


25


contacts the top edge of can seam


13


, while at its lower distal end


23


, contacts the top surface of lid


14


, thereby ensuring that the cutting wheel


10


and traction wheel


20


are oriented in optimum angle position for maximum and efficient shearing action of the lid


14


from the can


12


. In use, the cutting wheel


10


, by turning at an angle, shears the can seam


13


rather than cutting it. This action is more efficient and long lasting than a cutting blade which is level with the can lid


14


. The lid top contact


16


, can contact face


17


(which bears against the can wall


12


and prevents the cutting wheel


10


and traction wheel


20


from twisting to the side) and lid lifting pin


18


are also shown in dotted lines.





FIG. 14

illustrates an end partial cut-away view of the can opener with traction wheel and J-shaped can abutment contacting the top seam and top lid of a can. The important thing to note in

FIG. 14

is that through a combination of the J-shaped can abutment


22


, which simultaneously contacts the top of seam


13


and at its distal end


23


the top of lid


14


, the underseam contact edge


11


of wheel cutting blade


10


, which bears against the underside of the can seam


13


, and the right angle orientation of can contact face


17


and lid top contact


16


, which together bear against can wall


12


, the traction wheel


20


and cutting wheel


10


(not shown) are assured of being properly oriented and staying in position for maximum and efficient shearing action. The can


12


does not wiggle free or drop in elevation and is always maintained in right angle orientation with the top edge of the can


12


and lid


14


at the seam


13


, to thereby ensure maximum and efficient shearing action of the cutting wheel


10


on the seam


13


, as the opener


2


advances around the circumference of the seam


13


, by the operator turning hand crank


8


(not shown).





FIG. 15

illustrates a bottom isometric view of an alternative embodiment of the invention wherein the can lifter pin


24


is a bottle cap opening hook


36


.

FIG. 16

is an elevation view of the bottle cap opening hook


36


.




As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.



Claims
  • 1. A can opener comprising:(a) a handle; (b) a clamping lever associated with the handle; (c) a hand crank associated with the clamping lever and handle; (d) a wheel cutting blade mounted on the can opener; (e) a traction wheel which rotates when the hand crank is rotated; (f) a can lid top contact member mounted on an exterior of the can opener for contacting the cut lid of a can; and (g) a can lid lifting pin associated with the can lid top contact member for releasably catching an edge of a cut can lid, wherein the lid lifting pin is cylindrical and has a protrusion at the distal end thereof of a diameter greater than the diameter of the cylindrical lid lifting pin.
  • 2. A can opener as claimed in claim 3 wherein the protrusion is in the shape of a hemisphere.
  • 3. A can lifter for use in association with a can seam cutting can opener which comprises:(a) a can lid top contact member; and (b) a can lid lifting pin associated with the can lid top contact member, the can lid lifting pin cooperating with the can lid top contact member to grip a can lid and can seam of a cut can lid, wherein the lid lifting pin is cylindrical and has a protrusion at the distal end thereof of a diameter greater than the diameter of the cylindrical lid lifting pin.
  • 4. A can lifter as claimed in claim 15 wherein the protrusion is in the shape of a hemisphere.
  • 5. A can lifter as claimed in claim 15 wherein the protrusion is a hook for opening bottle caps.
US Referenced Citations (17)
Number Name Date Kind
1935680 Von Wolforsdorf Nov 1933 A
2556766 Mathieu Jun 1951 A
2715265 Hult Aug 1955 A
2861337 Behlau Nov 1958 A
3510941 Fyfe May 1970 A
RE27504 Smith Oct 1972 E
3719991 French Mar 1973 A
4726119 Lee Feb 1988 A
4734986 Peters Apr 1988 A
4782594 Porucznik et al. Nov 1988 A
5121546 Chong Jun 1992 A
5367776 Chong Nov 1994 A
5946811 Chang Sep 1999 A
6094828 Chong Aug 2000 A
6101727 Chong Aug 2000 A
6158130 Chong Dec 2000 A
6182368 So Feb 2001 B1
Foreign Referenced Citations (1)
Number Date Country
1318 Jan 1912 GB