Ergonomic can opener

Information

  • Patent Grant
  • 6510613
  • Patent Number
    6,510,613
  • Date Filed
    Thursday, July 20, 2000
    24 years ago
  • Date Issued
    Tuesday, January 28, 2003
    21 years ago
Abstract
An ergonomic, electric can opener sits squarely on a kitchen counter and has working features such that the user need not turn the opener to see where to place the can. The housing and working features of the can opener are situated at about a 45 degree angle to the front of the kitchen counter, and a person using the can opener can easily see both an operating lever and a place to insert the can for opening. The can opener is advantageous to persons with arthritic conditions, requiring no orientation in a preferred direction by a user, a minimum of force to operate, and automatic stopping.
Description




BACKGROUND OF THE INVENTION




The conveniences of daily life extend to the kitchen and to the many types of foods available year-round through modern preservation and canning techniques. While a great variety of foodstuffs is available in glass and plastic containers having screw-off lids, even more are available in “canned” form, that is, in a steel can, protected by a very thin coating of tin, and hermetically sealed from the outside environment. These cans are opened by a conventional can opener, which may be a hand-crank, a simple, hand-operated instrument, or an electric can-opener, using an internal electric motor to rotate the can against a cutting surface and thus to open the can. Such electric can openers are commonplace, and are distinguished by their reliability, ease of use, and overall convenience.




However, there is still room for improvement in these appliances, in that some persons, such as those with limited use of their hands, may find such appliances as presently constituted difficult to use. In particular, persons with arthritic conditions may find difficult the process of using a conventional electric can opener. Approaching a typical can opener from the front, the user may not be able to see the point of insertion, a serrated wheel to rotate a can, because it is hidden by a magnet assembly used to retain the severed can lid. To use an electric can opener, most right-handed persons will grasp a can in their left hand and the can opener in the right hand. The right hand is then used to orient and stabilize the can opener, typically by manipulating the opener so the user can see the wheel and more easily access the opener.




The can is then inserted under the serrated rotating wheel, which is operably connected to an electric motor for rotating the can. Once the can is inserted, the control lever is depressed, activating the electric motor to rotate the can against a cutting surface until the lid of the can is severed. It would be a great convenience to persons having limited use of their hands if they could more easily see the wheel and its relationship to the cutting surface, and thus would not need to grasp and rotate the can opener prior to use. Of course, there exist can openers which may be fixed in place, such as large, institutional openers, permanently oriented, but these can openers, being bolted into place, require the user to sacrifice the flexibility that portable appliances offer in a household kitchen. What is needed is an electric can opener that allows the user to see the rotating wheel without turning the can opener, where the can opener is sufficiently stable without being bolted to the counter-top, and also does not take up a great deal of counter space in the kitchen.




BRIEF SUMMARY OF THE INVENTION




This invention solves these problems by means of a new, ergonomic electric can opener. Recognizing that the person opening the can needs to see the rotating wheel without having to turn the can opener is the key to solving the problem. An electric can opener whose base is oriented “square” with a typical countertop, but whose housing is then rotated by about 30 to 90 degrees clockwise to that base, solves the problem.




Conventional can openers are typically square or rectangular in construction, having a front and back, and left and right sides. The base area is usually greater than the cross-sectional area of the housing to provide a stable platform for the can opener. Such a can opener will typically be placed on a kitchen counter-top in a manner that is “square with the world,” i.e., with the back of the can opener facing a back wall of the counter-top, and the front of the can opener toward the front of the counter. An operating lever of such a can opener will then be oriented toward the right side of the can opener, while the cutter and the rotating wheel (the point of insertion of the can) are on the front side.




In the improved can opener of the invention, the user need not grasp the can opener and rotate it. Instead, the housing of the can opener is molded and positioned at an angle to the suggested orientation of the molded base. Thus, when the user approaches the countertop and the can opener upon it, the user can see the serrated rotating wheel, and the point of insertion of the can into the can opener. The serrated wheel is on a surface on the user's left, while the operating lever is on a surface to the user's right. Instead of having to grasp and turn the can opener, the user lifts the operating lever, positions the can into its point of insertion, and depresses the operating lever to begin the process of opening the can. At the same time, a base of the can opener has features that are “square with the world” for easy orientation by the user with an external feature, such as a front edge of the countertop or the tabletop.




One embodiment of the invention is an ergonomic, electric can opener comprising a base and a housing mounted on top of the base. The base may be square or rectangular, with its front and back sides parallel to each other and positioned parallel to a countertop upon which the can opener is placed. In this orientation, the left and right sides of the base are perpendicular to the front and back sides, and are also perpendicular to the front edge of the countertop. The housing may be square or rectangular, and is mounted on top of the base, but is rotated through a vertical axis about 45 degrees from the base. That is, the entire top, along with the operable features of the can opener, is rotated about 45 degrees clockwise from its conventional position. The can opener further comprises a feed wheel operably connected to a motor and a switch for operating the motor, and an operating lever. The feed wheel and the operating lever, along with a cutting surface mounted on the housing, constitute the operable features of the invention.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a first embodiment of the invention.





FIG. 2

is a top view of the first embodiment of the invention.





FIG. 3

is a front view of the first embodiment of the invention.





FIG. 4

is a back view of the first embodiment of the invention.





FIG. 5

is a side view of the internals of an embodiment of the invention.





FIGS. 6



a


through


6




d


are side views of the internal parts of an embodiment of the invention.





FIG. 7

is a perspective view of a second embodiment of the invention.





FIG. 8

is a rear view of the second embodiment of the invention.





FIG. 9

is a top view of the second embodiment of the invention.





FIG. 10

is a cross-sectional view of a magnet assembly of the present invention.





FIG. 11

is a cross-sectional view of a blade sharpener.











DETAILED DESCRIPTION OF THE INVENTION





FIG. 1

is a perspective view of an embodiment of the present invention, an ergonomic electric can opener


10


. The can opener has a base portion


12


and a housing portion


13


. Housing portion


13


has a left front


14


and a right front


16


, in which the left front and right front are oriented at about 45 degrees from a front side


12




a


of base


12


. A scallop


15


may be part of the design for the can opener, for instance to make the can opener easier to grasp when it is moved for cleaning and the like. The can opener is depicted as it is meant for use on a counter-top, such as a kitchen counter-top (not shown), with a front edge


12




a


of the base


12


oriented generally parallel to the front edge of the counter-top, and facing straight at a user. Shown also in

FIG. 1

is an operating lever


22


, a can guide boss


24


and a serrated wheel


26


that rotates a can while it is being opened by cutting edge


30


, the cutting edge assembled as part of a cam


32


. Guide pin


28


helps orient a can into position for opening. Magnet holder assembly


34


holds a lid after it is severed from a can. A user approaching the can opener from the front does not need to rotate the can opener to see at least a portion of the top of serrated rotating wheel


26


, the point of insertion of a can into the can opener.





FIG. 2

is a top view of the ergonomic electric can opener of

FIG. 1

, depicting the base


12


of the can opener, and showing how the front base is aligned parallel with a kitchen counter-top edge


100


. It can also be seen from this figure that the can opener has a base having five sides,


12




a


,


12




b


,


12




c


,


12




d


and


12




e


, and a housing


13


with four sides,


14


,


16


,


18


and


20


. The four sides of the housing


13


are angled at about a 45-degree angle to sides


12




b


,


12




e


of base


12


. This 45-degree angle will be along a vertical axis passing through the height of the can opener, that is, an axis into the paper in FIG.


2


. Line


110


, bisecting the can opener, is perpendicular to the counter-top edge


100


. A user approaching the can opener from the front along line


110


will be able to see the operating lever


22


and top of the feed wheel (as shown in

FIG. 1

) without having to touch or orient the can opener. Power for a motor is supplied through electric cord


46


.





FIG. 2

also shows that the left front


14


and right front


16


are oriented at angles to the countertop in front In particular, a line


120


through the magnet holder


34


will form an angle of about 45 degrees with line


110


. Another line


130


that runs through the operating lever


22


will be at about 45 degrees to line


110


. Also shown in

FIG. 2

are a left rear side


18


and a right rear side


20


, left rear side


18


parallel to right front side


16


and right rear side


20


being parallel to left front side


14


. As is clear from

FIG. 2

, the lines of operation of the operating lever and the point of can insertion, along the magnet holder, are at right angles to each other and to the orientation of the left and right front sides


14


,


16


. While this is not essential for operation, a can opener is made easier to manufacture and assemble if this configuration is maintained. Thus, in one aspect of the invention, the operable features are maintained at right angles to each other and to the sides of the housing. In another aspect, lines drawn through the serrated wheel and the operating lever will be oriented about 45 degrees from the front of the counter-top, and also from the left and right sides of the base of the can opener.




The construction of the can opener in various embodiments may best be understood by reference to the orientation of the operating features. Since the point of the ergonomic can opener is to ease handling and to minimize the manipulation of the opener by a user, the can opener should be placed so that the operating features, that is, the operating lever and the serrated wheel, are oriented as in FIG.


2


. The can opener is oriented on a tabletop or counter top with the serrated wheel and the operating lever at angles of about 45 degrees to a front edge of the tabletop or counter top. With these features so oriented, a user need not grasp and rotate the can opener to insert a can and operate it. At the same time, the can opener has other visual cues so that the user can comfortably orient the can opener by sides parallel or perpendicular to the tabletop or counter top.




Visual cues are features of the environment used by the operator to orient himself or herself with respect to the can opener. The easiest and most obvious visual cue is a front of a countertop. If the front is not linear, then a back wall will serve for this orientation. Other features of a food-service area that may be used for such orientation could include, but are not limited to, an appliance surface, such as a side of a refrigerator; a back wall, such as a back wall of a kitchen; a sink side or edge; or any other similar surface that is parallel or perpendicular to a line of sight of a user. Thus, an orienting feature may be a sidewall, a front wall, a back wall, an edge, and so on. This is the reason for having a base and a housing mounted upon the base: the base cues the user to orient the can opener “square” with the orienting feature, such as a counter top or table-top, while the housing orients the operating features for ease of use.




The intended frontal orientation of such a can opener may not always be apparent, and the preferred embodiment of the invention builds in visual cues to a user as to the proper orientation of the can opener. Visual cues to the user as to the “proper” orientation of the can opener are important. These visual cues may be perceived from other structure, especially the sides of the base being parallel or perpendicular to a counter top or tabletop on which the can opener is placed. Thus, in

FIG. 2

, with the can opener and its operating features in the 45-degree orientation, sides


12




b


and


12




e


are perpendicular to the front edge


100


of the counter top or tabletop. A user is able to place the can opener in its preferred orientation by means of this preferred structure. In another embodiment, shown in

FIG. 9

, a three-sided housing is mounted upon a four-sided base. A user can visually align front edge


12




a


parallel to a front edge


100


of a countertop, while maintaining a 45-degree angle for the operating features. Another, secondary visual cue to a user is that the power cord should be at the rear of the can opener, as shown in

FIGS. 2

,


4


,


5


and


9


. A better method, however, is to realize that the advantage of the can opener is that a user should see both the serrated wheel and the operating lever without moving the opener. Thus, the preferred situation of the can opener is for lines through the operating features to be oriented about 45 degrees to the front edge of a countertop, as shown in

FIGS. 2 and 9

. As discussed below, the angle need not be only 45 degrees.





FIG. 3

is a view from the left front side


14


of the can opener


10


of the present invention. As can be seen from the figure, the sides


14


,


16


and


18


are at an angle with the base


12


, and base sides,


12




b


of the can opener. Scallop


15


is easily seen, as is operating handle


22


protruding from the right front surface


16


of the can opener. From the left front side


14


of the can opener, visible are a can guide boss


24


, serrated rotating wheel


26


, can guide pin


28


, cutting surface


30


, cam surface


32


, and magnetic holder assembly


34


.

FIG. 4

is a similar view from the rear, depicting the rear


20


of housing


13


and base


12


, with electrical cord


46


. Visible also is operating lever


22


, and in this embodiment, a gap


40


in the housing to accommodate a blade sharpener as an added feature of the can opener.





FIG. 5

is a side view of the internals of a can opener


10


of the present invention. The can opener has a base portion


12


and a housing portion


13


containing the working parts of the can opener. A motor


42


is typically connected through connector


44


and electrical cord


46


. The motor is connected to the serrated rotating wheel (not shown in this figure) through gear train


48


, typically several spur gears in a gear reduction train such that a higher-speed motor can turn the serrated feed wheel at a slower speed, and with more torque for opening cans. Depressing operating lever


22


activates the opener, by causing switch contacts


76


to close and supply power to the serrated rotating wheel. Depressing lever


22


also activates linkage


54


to set up an opposing spring cutter control


56


that automatically shuts off the motor when the lid has been severed from the can.




In order to use the invention, as depicted in

FIG. 1

, the ergonomic can opener is placed on a kitchen counter-top, with the front


12




a


of the base


12


oriented toward the front of the counter-top, that is, in the direction of the person who will use the can opener. Since front


12




a


is curved, we cannot say the front of the can opener is parallel to a countertop, but as seen in

FIG. 2

, sides


12




b


and


12




c


are perpendicular to countertop


100


. This is one way an owner may distinguish a preferred frontal orientation of the can opener. A can to be opened is placed adjacent the can guide


24


while the user lifts the operating lever


22


to move the magnet assembly


34


out of the way of the can. The can is placed such that its lip is atop the serrated rotating wheel


26


, and the operating lever


22


is then depressed, bringing a cutting surface


30


into contact with the top of the can. The serrated wheel bites into the lip of the can, and the lever activates the motor, which causes rotation of the can. While this occurs, the cutting surface separates the lid from the body of the can. When the operating lever is depressed, it causes the magnet assembly


34


to contact the lid of the can, and a magnet in the magnet assembly attaches itself to the lid. When the lid is severed from the can, a spring, which opposes the motion of the operating lever, causes a switch in the motor circuit to open, thus stopping the motor and the rotating wheel. The magnet holds onto the lid of the can and prevents it from sinking into the contents of the can. The can is then removed from the can opener and the opening operation is completed.




The embodiment shown in

FIGS. 1-5

is not the only way to practice the invention. While an angle of 45 degrees counter-clockwise is useful, any angle that allows a user to see the serrated rotating wheel is covered by the invention. It will also be recognized that angles from about 30 degrees to a full 90 degrees will provide the benefits of the invention. As applied to

FIG. 2

, this would be angle A, between base side


12




e


and housing side


16


. That is, angle A, zero degrees in a conventional can opener, may be anywhere between about 30 and 90 degrees in a can opener made according to this invention. Angle B, 90 degrees in a conventional can opener, is 90 degrees minus angle A. Angle A and Angle B are complementary in this construction, that is, angle A+angle B equal 90 degrees. Thus, in a can opener according to this invention, angle B may be between sixty and zero degrees. In a preferred embodiment of the invention, the right-angle orientation of the operating lever with respect to the rotating wheel-magnet assembly axis does not change. They remain at about right angles to each other for ease of manufacture, assembly, and operation. Angle A is the angle referenced in the claims.




A more detailed view of the internals of the can opener is illustrated in

FIGS. 6



a


through


6




d


. In

FIG. 6



a


, the operating mechanism is seen at rest. It includes the operating lever


22


and a linkage system


54


, which transmits a force through a lever


73


and a lever extension


74


to close switch contacts


76


to operate a motor. Lever


73


has a pin or rivet


66


that interfaces with arm


64


. Also included as part of the linkage are the arm


64


having a slot


68


with a front edge


69


and a rear edge


70


. The arm is operably connected to spring cutter control


56


. Spring cutter control


56


includes a biasing arm


58


and a spring arm


60


, as well as a control boss


62


. Operably connected to the operating lever is cutter


30


as part of a cam


32


for bringing a can (not shown) into contact with rotating wheel


26


.





FIG. 6



b


illustrates the operation of the can opener when a can


92


is placed into the can opener and operating lever


22


is depressed in the direction of arrow A. Lever extension


74


causes switch contacts


76


to close, starting a motor (not shown) and causing rotating wheel


26


to rotate, turning the can. When lever


73


moves clockwise, arm


64


moves to the right with its rear edge


70


in contact with rivet


66


. This causes rotation of the cam


32


and the cutter


30


in the direction of arrow B, causing cutter


30


to pierce the can


92


and begin removal of the lid of the can. Also rotating in the direction of arrow B is the spring cutter control


56


, with its biasing arm


58


and spring arm


60


, bringing them closer to control boss


62


. These levers are an Easy Touch® feature marketed by the assignee of the present invention, and are disclosed in U.S. Pat. No. 5,313,708, incorporated herein by reference. These levers allow a user to operate the can opener by applying about 1 pound of force to the operating lever


22


, a minimal force that enables persons afflicted with arthritis to more easily use the can opener of the present invention. The removal of the lid continues in

FIG. 6



c


. The arms


58


,


60


of the cutter control


56


are now in contact with the control boss


62


, setting up a force along arrow C opposing the previous motion, through the spring force of spring arm


60


on control boss


62


. This causes arm


64


to shift in the direction of arrow C, aligning rivet


66


in the front edge


69


of slot


68


. Cam


32


continues its motion in the direction of arrow B, with cutter


30


continuing to open can


92


by the rotation of wheel


26


in the direction of arrow D.




When the can is opened, as in

FIG. 6



d


, there is no longer a force exerted by the rotating wheel to keep the can in place between the cutter


30


and the rotating wheel


26


. With the relaxation of that force, the spring force set up by the spring arm


60


acting on boss


62


causes the cutter and the cam to rotate in the direction of arrow E. With the slot


68


and its front edge


69


aligned with rivet


66


, as in

FIG. 6



c


, this causes lever


73


to also rotate in the direction of arrow F. This causes lever extension


74


to move away from switch contacts


76


, opening the switch and stopping the motor. Thus, in this embodiment of the invention, the opening of the can causes the motor to automatically stop.




While a four-sided appliance is certainly useful, the benefits of the ergonomic can opener may be implemented in other configurations as well.

FIG. 7

depicts an embodiment in which the base


12


of the ergonomic can opener


10


includes four sides and a larger base for stability, but the upper operable part of the can opener, including housing


13


, has only three sides, an angled front side


14


, right side


16


and rear side


20


. Front side


14


is angled at about 45 degrees to the base. Because of this configuration, with the housing rotated clockwise from the base, a user approaching from the front can see the top portion of the serrated rotating wheel and need not grasp and rotate the can opener to comfortably operate it. The user will preferably insert a can at the approximately 45-degree angle using a left hand. The operating lever, at about a 90 degree angle to the axis of approach of the can, is located on a line at about the junction of the front


14


and right side


16


of the housing of the ergonomic electric can opener. Thus, this embodiment preserves the right-angle orientation of the can opener's working parts. At the same time, the user need not grasp and orient the can opener to use it, and the wide base insures the greater stability sought in the can opener.

FIG. 8

provides a rear view of this embodiment of the invention. Base


12


supports housing


13


, with “right” side


16


and “rear” side


20


visible. Also shown is operating lever


22


, and an opening


40


molded into the housing


13


to provide access to sharpening steels or ceramics should the can opener be equipped with an optional sharpening device for such use.





FIG. 9

provides a top view of this embodiment, in which base


12


is seen to be square or rectangular, having four sides,


12




a


,


12




b


,


12




c


, and


12




d


, while there are only three sides to the housing


13


, that is, the front


14


, right


16


and rear


20


sides. The front of the can opener is cued by the base and its front side


12




a


, parallel to countertop edge


100


, while the user is visually cued to the rear side


12




c


of the can opener via electrical cord


46


. A user approaching the properly-oriented can opener from the front along line


110


will be able to see the operating lever


22


and top of the feed wheel (as shown in

FIG. 7

) without having to touch or orient the can opener. A user approaching from the front along axis


110


will insert the can along axis


120


while using operating lever


22


along axis


130


. It will be appreciated that the angles between axes


110


-


120


and


110


-


130


are about 45 degrees, while there is a right angle between axes


120


-


130


It is not essential that the 45 degrees illustrated be strictly maintained to practice the invention. Angle A in a conventional can opener is zero degrees, while angle A between 30 and 90 degrees is sufficient to encompass this invention. Angle B is complementary to angle A, that is, angle B+angle A will equal 90 degrees. Thus, while angle B is ninety degrees in a conventional can opener, angle B will be between zero and 60 degrees in this invention. Angle A is the angle referenced in the claims.




In another aspect of the invention, shown in

FIG. 10

, the lid of the can is retained by the magnet assembly


34


, preventing the severed lid from falling into the can


92


.

FIG. 10

depicts the magnet assembly


34


, connected to housing


13


through an L-shaped arm


35




a


. The assembly also includes a magnet


35




b


and a spring


35




c


secured by a fastener


35




d


. The magnet assembly is moved by the action of the cam


32


, moving in concert with the cam and the operating lever (not shown in this figure). In another embodiment of the invention, a sharpener for household objects, such as knives or scissors, may also be included.

FIG. 11

depicts one such sharpener, a ceramic sharpener


41


, held in place by mounting device


43


inside housing


13


. Access to the sharpener is through longitudinal opening


40


, also depicted in FIG.


8


. Shown are two surfaces


41




a


,


41




b


of the sharpener.




The can openers of the present invention may be manufactured from any suitable materials, including thermoset materials, metals, or thermoplastic materials. Molding allows the automatic and accurate placement of internal bosses and features useful in assembling the internal parts of the can opener. In a preferred aspect of the invention, the bases and the housings are molded from thermoplastic materials, in order to provide lightweight materials at low cost. It is also preferred to mold such can openers in several parts for ease of assembling both the external parts and the internal parts. While the base is advantageously molded in a single piece, the housing is better molded in two sections, so that the internal parts may be assembled inside and then the can opener closed by assembling the housing to the base with the internal parts assembled inside. Any suitable plastics may be used, including nylons, polyesters, ABS, HDPE, Lexan, and polycarbonates. In a highly preferred mode, can openers made from ABS are injection molded quickly and easily at low cost. A variety of colors are also available in these materials, allowing for more manufacturing and consumer preference options.




While this invention has been shown and described in connection with the preferred embodiments, it is apparent that certain changes and modifications, in addition to those mentioned above may be made from the basic features of this invention. For example, angles other than 45 degrees may be used to angle the sides of the can opener from the base without departing from the invention. Any angle that allows a user to see the serrated rotating wheel without moving or re-positioning the can opener will work. The invention thus far has been largely directed to use by a right-handed person, with the features of the can opener being a serrated wheel on the left and an operating lever on the right. The invention will work as well with an operating lever on the left side and a serrated feed wheel on the right. While this invention incorporates other improvements, such as a minimum of force to close the internal operating switch and begin opening a can, it is not necessary to include such refinements, and a can opener without an Easy Touch® feature will work as well for the intended purpose of allowing an easier line of sight. Nor is it necessary to cause the can opener rotating wheel to stop automatically, although this feature certainly is convenient to users. Accordingly, it is the intention of the applicants to protect all variations and modifications within the valid scope of the present invention. It is intended that the invention be defined by the following claims, including all equivalents.



Claims
  • 1. An electric ergonomic can opener, comprising:a housing; a motor mounted within the housing; a switch mounted within the housing and connecting a source of electric power to the motor; a feed wheel mounted on a shaft and operably connected to the motor, for rotating a can; an operating lever substantially perpendicular to the feed wheel shaft, mounted on the housing and operating the switch; and a cutter mounted on the housing and operably connected to the operating lever, wherein the feed wheel shaft and the operating lever are each oriented substantially at an angle of about 45 degrees to a front of the can opener.
  • 2. The can opener of claim 1, further comprising a base, wherein the housing is mounted on the base at an angle of about 45 degrees to the base, and the feed wheel shaft and the operating lever are each oriented substantially at an angle of about 45 degrees to the base.
  • 3. The can opener of claim 1, further comprising a base, wherein the housing is mounted on the base at an angle from 30 to 90 degrees from the base, and at least one side of the base is parallel or perpendicular to the front edge of the countertop.
  • 4. The can opener of claim 1, wherein the operating lever and the top of the feed wheel are visible to a user from the front of the can opener, without having to move the can opener.
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