US2879589A

US2879589A - Can opener

Info

Publication number: US2879589A
Application number: US702423A
Authority: US
Inventors: Ulke William
Original assignee: John Oster Manufacturing Co
Current assignee: John Oster Manufacturing Co
Priority date: 1957-12-12
Filing date: 1957-12-12
Publication date: 1959-03-31
Anticipated expiration: 1976-03-31

Description

W. U L K E CAN OPENER March 31, y1959 Filed Deo. Al2, 1957 W. U| KE CAN OPENER Mafh 31, 17959 4 Sheets-shes;C 2

LV1/[1:7122 Mk@ s Filed Dec. l2. 1957 w. ULKE CAN OPENER March 31, 1959 4 sheets-sheet 3 Filed Dec. 12, 1957 March 31,1959 w. ULKE l 2,879,589

' CAN OPENER 4 shams-s119629 4 Filed Dec. l2, 1957 United States Patent O 'CAN OPENER William Ulke, Milwaukee, Wis., assignor to John Oster Manufacturing Co., Milwaukee, Wis., a corporation of Wisconsin Application December 12, 1957, serian-v0. 702,423

15 claims. (Cl. 311-4) This invention relates generally to improvements in i ce Figure 2 is a View of the front end of the opener, taken on the plane of the line 2 2 in Figure l, the can being removed butlthe opener being shown in its operative cutting condition; v

y Figure 3 is la view similar to Figure 2, but with the opener in its inoperative can receiving condition;

Figure 4 is an exploded perspective view of the c'a'n opener; 4 v Figure 5 is a side elevational view of the can opener shown detached from its supporting pedestaland power unit, but with a can in position being cut, parts of said view 4being broken away and in section;

Figure 6 is a sectional view taken along the line 66 in Figure 5 and looking upward towards the underside of the opener; Figure 7 is a fragmentary detail view showing a portion of the cutting wheel and feed wheel with a can in position therebetween, the can being shown in section and the entire View being drawn to a greatly enlarged scale to more clearly illustrate the manner in which the cutting lwheel forms the cut in the end wall of the can and coacts n with the feed wheel to assure free removal of the severed this type very diiiicult. This is especially true where the opener is to be driven by an electric motor since any jamming of the can may result in damage to the opener or loss of contents of the can to be opened. The problem is further complicated by the fact that to :be fully satisfactory, the opener must perform so that the severed end wall may be easily removed.

The meandering cutmade by most can openers produces metal slivers and burrs which make careful handling of the opened can a necessity. This objection can be overcome, or at least materially lessened, through accurate positioning and firm holding of the can during'lthe opening thereof, coupled with uniforml delivery of power to the opener; but the means heretofore employed in an attempt to gain this result, and which often involved ythe use of springs and guides to position the can, were effective for only a very limited yrange of can sizes and shapes. l l

It is, therefore, the purpose and object of this invention to provide a can opener of the type described which overcomes the deficiencies of prior openers, and which is truly universal so as to perform we1l','regardless of the size or shape of the can or the thickness of the metal of which it is made. j

The invention achieves this objective through a new shape for the cutting wheel and a novel coaction between the cutting wheel and the feed wheel, which not only holds the can in the correct position for opening but also assures free removal of the severed end wall and a smooth edge for the opened end of the can.

With the above and otherv objects in yiew which will appear as the description proceeds, this inventionresides in the novel construction, combination and arrangement of parts substantially as hereinafter described andmore particularly deined by the appended claims, it being understood that such changes in the precise embodiment ,of

the hereindisclosed invention may be made as comewithin the scope of the claims. t

- The accompanying drawings illustrate one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which: V *i j Figure l is a side view, with parts broken away and in section, of a can opener embodying this invention, and illustrating the same mounted una` combination supporting pedestal and power unit;

can top and a smooth edge for the opened can; and

Y Figure 8 is a top plan view of a can which has had an end wall severed therefrom with a can opener constructed in accordance with this invention, but with the severed end wall still in position to illustrate the unusual 'clearance between the edge of the end wall and the side wall which this invention provides.

Referring to the drawings, in which like numerals designate like parts throughout the several views, the numeral 1 designates a support or pedestal upon which the can opener of this invention, designated generally by the numeral 2, is detachably mounted. The support or pedestal containsan electric motor 3 and a speed reduction unit 4 having an output shaft 5 which projects into a socket 6 opening to the front wall of the support or pedestal. The body or housing 7 of the can opener has a boss 8 thereon which fits into the Vsocket and is held therein with the opener properly oriented, by a thumb screw (not shown) threaded through a portion of the support or pedestal'to bear against the boss 8.

` The body or housing 7 of the opener has a shaft 9 journalled in

bearings

10 and 11 coaxial with its boss 8, to be'drivingly connected to the output shaft 5 by means of a ,tongue and groove coupling 12, upon proper attachment of the can opener to the support. The shaft 9 is held against outward axial displacement by a shoulder 13 onits inner end which bears against the adjacent end of'bearing 11 through a suitable thrust washer.

The outer end of the shaft 9 projects beyond the front face of the body or housing 7 and has an eccentricV 14 journalled thereon to be eccentrically rotated about the shaft by a handle 15 which has its hub portion keyed to the eccentric, preferably by having a non-circular boss on the rear of the eccentric received in a correspondingly shaped hole in the handle hub. Movement of the handle about the shaft thus rotates the eccentric about the shaft axis, and since the maximum throw of the eccentric is desired, its rotation is limited to 180. For this purpose,

I the hub portion of the handle has an arcuate slot 16 to strained to rectilinear up and down motion by having parallel at surfaces 18 on its upper end portion slidably engaged with inwardly facing hat vertically disposed shoulders 19 on the housing or body, and by the reception of the outer end portion of the pin 17 in a slot'2`0 whichY j i extends straight down from an oval shaped hole 21 in the medial portion of the face plate. The hole 21 has the eccentric 14 received therein and has its greatest dimension transverse to the permitted motion of the face plate to accommodate the swing of the eccentric as it rotates in its orbit, but in the direction of motion to be produced, i.e. vertical, the eccentric fits the hole 21 quite snugly. In fact, to assure maintenance of this close it, the bottom edge of the hole 21, which receives the greatest wear during use, is formed by an insert 22 of hardened steel. Thus, as the handle is swung from one position to another, the resulting 180 rotation of the eccentric raises and lowers the face plate.

The eccentric 14, the handle, and the face plate are held in proper assembled relationship by the securance of a feed wheel 23 to the outer end of the shaft 9. The lfeed wheel is preferably threaded onto the shaft 9 to .facilitate assembly and has its hub drawn tight against a shoulder on the front end of the shaft. A rearwardly facing shoulder on the hub of the feed wheel holds a 4locating spring 24 in place overlying the coplanar front `surfaces of the face plate 18 and the eccentric 14, and coacts with the non-circular boss on the eccentric to hold the face plate on the eccentric. A washer 25 confined between the shoulder on the feed wheel and the locating spring stiffens the latter and covers the ends of a vertically elongated hole 24 in the spring through which the reduced rear end portion of the hub on the eccentric s received, the vertically elongated shape of the hole 24 being necessary to permit the spring -to move up and .down with the face plate.

Since the hub of the feed wheel is drawn tight against a shoulder on the shaft 9, the provision of a thrust washer 26, which may be a `spring washer, between the eccentric l,and the front end of the bearing 10 holds the shaft 9 `=against undue end play.

The face plate `is preferably a stamping and has a pair of .forwardly projecting arms 27 on its upper end. These arms provide the parallel surfaces 18' which slidably engage the shoulders 1.9 to guide the up and down motion of the face plate, and at their extremities the arms are bent inward to provide horizontal at unyielding holddown abutments 28. The abutments 28 engage the top of the rim of a can in position to be opened and press kthe underside of the rim against the edge of the feed wheel, when the handle is swung around to draw. the face `plate down. The edge of the feed wheel, being serrated as shown, bites into the rim of theV can and advances the same through the cutting zone as the feed wheel turns.

Between its arms27 the face plate has a forward em- .bosture 29 with an inclined flat lower wall 29', and projecting perpendicularly from this inclined wall in fixed relation thereto is a `stub shaft 30 upon which the cutting wheel k31 of the opener is freely rotatably mounted. The Ystub As halft 30 has .a .forwardly facing shoulder 30' on its anchored end to provide a thrust bearing for the wheel, and at its outer free end portion the stub shaft has a pair of fiat bottomed grooves 32 in the opposite sides thereof.

A bifurcated combination wheel retaining member and magnet vholder 33 is tightly though `removably engaged in the grooves 32 to detachably secure the cutting wheel. in position and also support a magnet 34 by which the severed end wall of the can is held from dropping into the can upon completion of the opening operation. To allow the magnet to position itself properly with respect tothe top of the can, the connection between the magnet and its holder comprises a headed pin 35 projecting up from a `cage in which the magnet per se is fixed and passing loosely `through a hole in the holder. This prov ides a substantial amount of freedom for the magnet and permits `the magnet to yseat itself Yupon the can` top as .the @amis placed .in pgsitionrreparatery to .being Qpenede The locating spring 24, as already described, overlies the front of the face plate and partakes of all motion imparted to the face plate. It is secured against edgewise displacement with respect to the face plate by having its upper portion 36 disposed at an angle to overlie the inclined flat lower wall 29' and provided with an aperture 36' to closely receive the adjacent anchored end of the stub shaft 30.

The locating function of the spring 24 is performed by a pair of resilient arms 37 projecting forwardly from the opposite side edges of its upper inclined portion 36. As best Vseen in Figures 2 and 6, these arms 37 embrace or straddle the cutting wheel, and have their outer edges curled to provide smooth bearing surfaces 37 so located and disposed as to bear obliquely against the edge of a can in position to be opened and to press yieldingly thereagainst. In so doing, the spring arms 37 aid in properly positioning the can and steadying it during the opening operation.

The resilience of the locating spring 24 and especially its arms 37 assures proper centering of the can on the feed wheel, regardless of the size or shape of the can, it being understood that the axes of the cutting wheel and the feed wheel lie in a common vertical plane, and

that the positioning spring is symmetrically bisected by this plane.

Additional support and guidance for the can is provided by afoot 38 which projects forwardly from the bottomlof the face plate to engage the adjacent side of .the canand hold lthe same at a slight angle to the front face ofthe feed wheel, as best seen in Figure 5.

Operation In using the opener of this invention, its handle is first moved to the position shown in Figure 3, if it is not a1- ready in that position. `In this position of the handle, the `face plate and, of course, all the structure carried thereby including the cutting wheel, is in its elevated or raised position. This permits the can to be placed in position with the underside of its rim (at the top of the can) seated upon the top of the feed wheel, and the side of the can bearing against the foot 38. The handle is then moved to the position shown in Figure 2. This movement of the handle lowers the face plate, causing the cutting wheel to pierce the top or uppermost end wall of the can and forcing the hold-down abutments 28 against the top of the rim of the can, whereupon the serrated edge of the feed wheel bites into the rim. This lowering of the face plate also brings the magnet support to a position at which engagement between the magnet and the top or upper end wall of the can is permitted.

As shown in Figures 1, 5 and 7, the cutting wheel has a conical rear Aface 40 which is substantially parallel to the zfront face of the feed wheel where the common vertical plane containing the axes of the two wheels intersects this conical rear face, and in the lowered position of `the cutting wheel its conical rear face overlies the front face of the feed wheel. This condition, of course, results from the fact that the axis of the cutting wheel is disposed at a predetermined downward angle with respect to the horizontal, and from the specific location o f the cutting wheel with respect to the feed wheel. The normal clearance between the conical rear face 40 of the cutting wheel and the front of the feed wheel when the cutting wheel is lowered is slightly less than twice the thickness of the lightest gage metal used in the making of cans. Accordingly, as best shown in Figure 7, when the cutting wheel is brought down into its cutting position to pierce the top of the can, the rim of the can is clamped between the conical rear face of the cutting wheel and the front face of the feed wheel, the conical rear face 40 of ,thecutting wheel engaging the inside flange 41 of the rimand the front of the feed wheel engaging ltheportion 4 2 pftheside of the `can directly beneath the rim.

This clamping coaction between fthe two wheels, of

itself, holds the canin proper position for the cutting operation and, for most can shapes, would be suicient for this purpose. However, to steady the can and to assure a smooth cut, the locating spring 24 acts obliquely downwardly and laterally against the rim of the can at equispaced distances out from the common plane containing the axes of the cutting wheel and the feed wheel, the resilience of the locating spring accommodating the variations in size and shape of the cans. f Since the normal clearance between the back of the cutting Wheel and the front of the feed wheel is less than the combined thickness of the two layers of metal interposed therebetween, it is evident that the mounting of at least one of the wheels must be resiliently yieldable. The feed wheel, being solidly supported against rearward displacement with respect to the face plate by having its hub bearing thereon through the washer 25 and the locating spring 24, cannot yield. Hence, it is the mounting for the cutting wheel which must yield slightly as the rim of the can is clamped between the two wheels. This requirement is conveniently satisfied by the inherent resiliency of the stamped metal face plate which allows it to flex under a force tending to spread the wheels apart. By this simple expedient, therefore, the opener is adapted to handle cans made with different metal thicknesses.

Heretofore, in can openers of this type where rotary cutting wheels were employed, the cut formed thereby was made directly adjacent to the rim, as shown for instance in Patent No. 2,244,846. With the cut thus located, it is difficult` to lift lthe severed top from the opened can, since the diameter of the severed top invariably is so close to that of the open end of the can that the top cannot be lifted directly oif the can. To overcome this difliculty, the present invention locates the cutting zone at a substantial distance radially in from the inside 41 of the rim. This is done by bevelling the extreme outer edge portion 43 of the conical rear face 40 to dispose the same at an angle somewhat steeper than that of the conical rear face 40 and, preferably, the front face of the cutting wheel is likewise bevelled, as at 44, so as to give the cutting wheel a V-shaped marginal portion defining a sharp cutting edge 45.

By this specific shape of the cutting wheel, the cutting zone or, more specifically, the circular line of the cut, is spaced a substantial distance inwardly of the inner surface 41 of the rim and the inside surface of the side wall of the can. But locating the cut radially inwardly in this way introduces another problem. Since the cut is made some distance awayl from the side wall of the can, the pressure exerted on the top of the can by the cutting wheel stretches the material considerably more than it would if Vthe cut were directly adjacent to the side wall. In other words, the ratio of shear to stretch is less favorable to the attainment of good clearance between the severed can top and the open end of the can. To overcome this disadvantage and assure the desired results, the parts are so constructed and related that the conical rear face 40 of the cutting wheel overlies the inner surface of the side wall of the can well below the plane of its top wall and thus the unsevered marginal edge portion of the end wall is flattened against the side Wall, as shown at 46 in Figure 7. As a result, the open end of the can is substantially larger than the severed top or lid, and, since the clearance is uniform all the way around, as shown in Figure 8, no difficulty is experienced in lifting the severed top from the opened can.

Also, by virtue of this flattening or ironing action produced by the conical rear wall of the wheel, the opened can has .an exceptionally smooth edge entirely free from bui'rs or sharp slivers.

, Obviously, of course, after the cut is completed, the magnet retains the severed top or lid as the handle is swung back to its Figure 2 position, to raise the cutting wheel Vand free the can for removal.

From the foregoing description, taken in connection with the accompanying drawings, it will be readily apparent to those skilled in this art that the can opener of this invention is an important and significant improvement over all prior can openers.

What is claimed as my invention is:

1. A can opener having a feed wheel which rotates on a substantially horizontal axis and has its periphery formed to have driving engagement with the underside of the rim at the top of a can to be opened, a cutting wheel to pierce and sever the top of the can from the rest thereof, and means mounting the feed wheel and the cutting wheel for relative vertical motion to and from an operative positional relationship, that: the feed wheel has a front face, the upper portion of which supportingly engages the side of the can directly below its rim; the cutting wheel rotates on an axis inclined to the horizontal and lying in a vertical plane containing the axis of the feed wheel, the cutting wheel has a conical rear face radially inwardly of its cutting edge and substantially tangent toa vertical plane which is normal to said first designated vertical plane and is spaced from the can supporting face portion of the feed wheel a distance less than twice the wall thickness of the can, the cutting wheel has a substantially ilat front face normal to the axis about which the cutting wheel rotates and hence inclined to said Vertical plane to which its rear face is tangent, said front and rear faces of the cutting Wheel being beveled to define the actual cutting edge of the Wheel and to locate said cutting edge farther from the can supporting face portion of the feed wheel than its rear conical face so that the cut formed in the can top by the cutting wheel is spaced a distance in from the rim of the can, and said cutting wheel being so disposed with respect to the feed wheel that when said wheels are in their operative positional relationship the lower peripheral portion of the cutting wheel extends down substantially below a horizontal reference plane tangent to the top of the feed wheel which reference plane substantially coincides with the top of a can in position to be opened so that said portion of the cutting wheel. protrudes through and extends a distance below the top of the can with the conical rear surface of the wheel pressing against the unsevered marginal edge portion of the can top for substantially its full width, to thus iron the same tightly against the side of the can while the inclined front face of the cutting Wheel and its beveled edge coact to curl down the inner edge of the cut being formed by the wheel during the opening of the can.

2. In a can opener: a cutting wheel to pierce and sever the top of a can, said cutting wheel comprising a hub with a flange at one end, said flange having a front face substantially normal to the axis of the wheel and a substantially conical rear face, and the contiguous portions of said front and rear faces being uniformly and substantially identically beveled to define the cutting edge of the wheel, the bevel on the substantially conical rear face locating the cutting edge forwardly of said substantially conical rear face and the bevel on the front face providing an inclined approach from the cutting edge to said front face.

3. In a can opener of the type having a feed wheel for engaging and driving the rim of a can and a cutting wheel for piercing and severing the end wall of a can adjacent to the rim driven by the feed Wheel: means for positioning a can in driving engagement with said feed wheel and in cutting engagement with said cutting wheel; a peripheral cutting edge on said cutting wheel disposed to pierce and sever the end wall of the can; a substantially conical face on said cutting wheel inwardly of its cutting edge to engage the inside of the rim of the can and thereby clamp the rim of the can against the feed wheel, said substantially conical face overlying enough of the feed wheel to atten the peripheral, unsevered portion of the end wall against the side wall'of characterized by the fact` the can and provide clearance to facilitate removal of the severed portion ofthe end wall from the remainder of the can; and a second steeper angled conical Lface on the Acuttingwheel circumscribing the first substantially conical face and joining the same, said second conical face terminating in thecutting edge of the Wheel so that the cutting zone of the opener is spaced radially in from the surfaceof the can engaged by the rst substantially conical face.

v 4. In a can opener: a cutting wheel having a substanltially V-shaped cutting edge defined by front and rear conical faces, the rear conical face joining with a second rear substantially conical face which is atter than said first designated rear conical face; means to support a can to be opened; and means freely rotatably mounting the cutting wheel for rotation about an axis so inclined with respect to the can positioning means that the flatter substantially conical rear face of the cutting wheel engages the inside of the rim of the can to be opened and thereby disposes the cutting edge of the wheel at a distance in from said rim.

5. In a can opener of the character described: a feed wheel having a serrated edge to engage the underside of the rim of a can, said feed wheel having a substantially at front face to engage the side of the can; a cutting wheel having a substantially V-shaped peripheral portion defining a sharp cutting edge; a hub on the rear of the cutting wheel substantially smaller in diameter than the cutting edge; a substantially conical rear face for the wheel joining the hub with its cutting edge, said substantially conical rear face being substantially flatter than the adjacent conical rear face of the cutting edge; means rotatably mounting the cutting wheel for rotation about an axis lying in a common plane with the axis of rotation of the feed wheel and inclined with respect to the feed wheel axis an amount such that where said common plane intersects the conical rear face of the cutting wheel said conical rear face is substantially tangent to the front face of the feed wheel, said faces of the two wheels opposing one another and being spaced apart a distance to clamp the rim of a can therebetween, said disposition of the wheels locating the cutting zone a substantial distance away from the rim of the can.

6. The can opener of claim 5, further characterized by the fact that the conical rear face of the cutting wheel overlies the front of the feed wheel an amount greater than the depth of the rim of a can to be cut so that the unsevered marginal portion of the end wall of the can is rolled at against the inside surface of the can during the opening operation.

7. A can opener comprising: a body having a front face which is disposed vertically in the normal use of the opener; a drive shaft journalled in the body with its outer end portion projecting perpendicularly from the front face thereof; a feed Wheel having a serrated edge iixed to the projecting outer end portion of the shaft; a face plate overlying the front face of the body; cooperating means on the body and the face plate constraining the face plate to translatory motion transverse to the shaft, said permitted motion of the face plate being up and down when the body is in the position it occupies in the normal use of the opener; an eccentric journalled on the shaft between the feed wheel and the front face of the body; the face plate having a hole in which the eccentric is received, said hole being elongated in the direction transverse to the permitted motion of the face plate to accommodate the swing of the eccentric but fitting the eccentric closely in the direction of face plate motion so that rotation of the eccentric imparts translatory motion to the face plate; a handle having a hub portion connected to the eccentric-and lying between the face plate and the front face of the body for imparting rotation to the eccentric; a stub shaft fixed to the face plate with its axis lying in a plane containing the axis of the feed wheel and drive Shaft .and Parallel t0 the Permitted @011011 0f the face plate, said stub kshaft being above the `feed wheel inthe normal position of the body but being inclined downwardly; .and cutting wheel freely rotatably journalledion saidustub shaft, said cutting wheel having ja conical rear face to yoverlie the front face of the feed wheelI when the handle is lactuated to move Vthe Iface plate toits lowermost position whereby the rim of a can to be opened may be clamped between the conical rear face of the lcutting wheel and the front face of the -feed wheel while the serrated edge of the feed wheel engages the underside of said rim and the cutting wheel pierces the top of the can.

8. The can opener of claim 7, further characterized by the fact that the cutting edge of the cutting wheel is spaced farther away from ythe front face of the feed wheel than said conical rear face of the cutting wheel to thereby locate the cutting zone at a predetermined distance inwardly of the rim of the can.

9. The can opener of claim 7 further characterized by the fact that the face plate has a degree of resilience to yield slightly under a force tending to increase the dis.- tance between the rear conical face of the cutting wheel and the front face of the feed wheel to thereby accommodate cans formed of different gage material.

l0. The can opener of claim 7 further characterized by the fact that the outer end portion of the stub shaft has a pair of grooves in its opposite sides just forwardly of the front face of the cutting wheel, and by the provision of a bifurcated retaining member detachably engaged in said grooves to removably hold the cutting wheel in place, said retaining member having a portion thereof extending forwardly to provide a magnet support overlying the top,

of a can in position to be opened.

ll. The can opener of claim 7 further characterized by the provision of a pair of spaced downwardly facing abutments on said face plate lying in a common plane parallel to the axis of the shaft and intersecting the axis of the cutting wheel with one abutment at each side of the cutting wheel to engage the top edge of a can in position and thereby press the underside of its rim against the serrated edge of the feed wheel.

l2. The can opener of claim ll further characterized by the provision of a pair of resilient locating fingers projecting forwardly from the face plate, one at each side of the cutting wheel and between said pair of abutments, said locating fingers having inclined edges lying in a plane substantially parallel to the plane of the cutting edge of the wheel to resiliently engage and press obliquelyagainst the top edge of the can.

13. The can opener of claim 12 further characterized by the provision of a forwardly projecting foot on the face plate spaced a substantial distance beneath the feed wheel to engage the side of a can and hold the same tilted VVslightly away from the front face of the wheel.

V14. A can opener having a feed wheel -which rotates on a substantially horizontal axis and has its periphery formed to have driving engagement with the underside of the rim at the top of a can to tbe opened, a cutting element to pierce and sever the top of the can from the rest thereof, and means mounting the feed wheel and cutting element for relative vertical motion to and from an operative positional relationship, characterized by the fact that: the feed wheel has a front face the upper portion of which supportingly engages the side of the can directly below its rim; and the cutting element has a downwardly facing cutting edge disposed at a negative angle to the direction of relative motion between the cutting element and the can top portion upon which the cutting edge acts during the can opening operation, said cutting edge `crossing a horizontal reference plane tangent to the top of the feed wheel when the cutting element and the feed wheel are in their operative positional relationship, and which horizontal reference plane substantially coinc ides-with Athe'top of .a canin position to be opened-so that the working portion of the cutting .element Aprotrudes through and a distance below the can top, the working portion of the cutting element being intersected by a first vertical reference plane which contains the axis of the feed wheel, and on said plane 4being V-shaped in cross section with upwardly diverging front and rear surfaces, its rear surface being convex and tangent to a second vertical reference plane normal to said trst verti-cal reference plane and spaced from the can supporting face portion of the feed wheel a distance less than twice the wall thickness of the can, its front surface being sub stantially flat and by virtue of the divergence of the front and rear surfaces being inclined and where it crosses horizontal reference plane being spaced a substantial distance from the can supporting face portion of the feed wheel, the contiguous edge portions of the front and rear surfaces being uniformly beveled to form the cutting edge, the bevel on the rear surface spacing the cutting edge farther from the can supporting face portion of the feed wheel than said convex rear surface so that the cut formed in the can top is spaced from the side wall of the can and leaves an unsevered marginal edge portion, the bevel on the front surface, by virtue of its uniform width disposing the cutting edge in a plane parallel with and rearwardly of said substantially at inclined front surface of the cutting element and forming an abmpt approach to said front surface to more effectively roll down the inner edge of the cut as it is being formed in the can top to assure the severed can top being substantially smaller than the mouth of the opened can, and the width of the bevel on the rear surface being such that where said first vertical reference plane intersects the cutting edge the heel of said bevel lies below said horizontal reference plane far enough to assure the convex rear surface of the cutting element acting upon the entire width of the unsevered marginal edge portion of the can top to iron it down against the side wall of the can.

15. In a can opener: a rotatably mounted feed wheel; means for driving the feed wheel; a cutting wheel having a substantially V-shaped cutting edge defined by front and rear conical faces, the rear conical face joining with a second rear conical face which is atter than said first designated rear conical face; means for positioning a can to be opened in driving engagement with the yfeed wheel and in cutting engagement with the cutting wheel; means freely rotatably mounting the cutting wheel for rotation about an axis so inclined with respect to the can positioning means that the flatter conical rear face of the cutting wheel engages the inside of the rim of the can to be opened and thereby disposes the cutting edge of the wheel at a distance fromv said rim; the axes of the two wheels lying in a common plane; and the means for positioning a can in driving engagement with the feed wheel and in cutting engagement with the cutting wheel, including spring arms embracing the feed wheel symmetrically of said common plane, the extremities of said spring arms providing bearing surfaces dis posed at an angle to exert lboth a lateral and a downward force against the upper edge of the can.

References Cited in the tile of this patent UNITED STATES PATENTS 1,071,974 Walther Sept. 2, 1913 1,553,599 La May Apr. 14, 1925 1,989,807 Jeppsson Feb. 5, 1935 2,012,955 Cabot Sept. 3, 1935 2,204,368 Kublin June 11, 1940 2,244,846 Moeller June 10, 1941 2,437,234 Webb May 2, 1948 2,441,322 Jager May 11, 1948 2,532,898 Drugman Dec. 5, 1950 2,568,962 Lindahl Sept. 25, 1951 2,573,031 La Forto Oct. 30, 1951 2,573,427 Frolich Oct. 30, 1951 2,579,189 Jenson Dec. 18, 1951 2,601,303 Landry June 24, 1952 2,602,991 Landry July l5, 1952 2,615,241 Lawrence Oct. 28, 1952 2,624,110 Acker Jan. 6, 1953 2,736,091 Moore et al Feb. 28, 1956 2,789,345 Klassen Apr. 23, 1957 2,825,963 Stykes Mar. 11, 1958 UNITED STATES PATENT OEEICE CERTIFICATE OE CORRECTION Patent Nm, 2,879,589 March 31, 1959 William Ulke' n the printed :Specificationv It is hereby certified that error appears n and that the said Letters of the above numbered patent requiring oorrectio Patent should read as corrected below.

Column 9, line 13, after "crosses" insert w said me.,

Signed and Sealed this 14th day of July l959 ROBERT C. WATSON Commissioner of Patents