US3689997A

US3689997A - Electric can opener with removable hand lever and frame engaging pin assembly

Info

Publication number: US3689997A
Application number: US47937A
Authority: US
Inventors: Robert E Mclean
Original assignee: Rival Manufacturing Co
Current assignee: Rival Manufacturing Co
Priority date: 1970-06-22
Filing date: 1970-06-22
Publication date: 1972-09-12
Anticipated expiration: 1989-09-12
Also published as: CA941596A

Abstract

An electrically powered can opener has suitable components for initiating power-pierce and automatic shutoff. At the same time, the selective removal of the can opener cutter mounting plate which carries the cutter element thereon is provided for. The can opener frame is apertured to movably receive a hand lever assembly which includes the cutter mounting plate, the hand lever and an interposed plate and spring combination to assist in the operative movement of the cutter mounting plate. A spring biased lever is pivoted to a portion of the can opener frame and operates in accordance with the manual movement of the cutting element against the end of the can to initiate power-pierce and to maintain the can opener motor on until the end of the can has been sheared therefrom. At this time, the lever pivotally moves to automatically shut off the power to the can opener motor. A spring biased push button operated latch engages a pin member extending from the hand lever assembly. It permits the removal of same (along with the cutting element carried on the cutter mounting plate) by manipulation of the push button latch structure.

Description

Unite States Patent McLean 1 Sept. 12, 1972 [541 ELECTRIC CAN OPENER WITH REMOVABLE HAND LEVER AND FRAME ENGAGING PIN ASSEMBLY [72] Inventor: Robert E. McLean, Raytown, Mo.

[73] Assignee: Rival Manufacturing Company,

Kansas City, Mo.

[22] Filed: June 22, 1970 [21] Appl. No.: 47,937

52 US. Cl. ..30/4 R 51 rm. c1. ..B76b 7/38 581 Field of Search ..30/4, 8.5, 9

[56] References Cited UNITED STATES PATENTS 3,487,542 1/1970 l-lamwi ..30/4 3,496,635 2/1970 McLean ..30/4

Primary Examiner-Andrew R. Juhasz Assistant ExaminerGary L. Smith Attorney-Scofield, Kokjer, Scofield and Lowe [57 ABSTRACT An electrically powered can opener has suitable components for initiating power-pierce and automatic shutoff. At the same time, the selective removal of the can opener cutter mounting plate which carries the cutter element thereon is provided for. The can opener frame is apeitured to movably receive a hand lever assembly which includes the cutter mounting plate, the hand lever and an interposed plate and spring combination to assist in the operative movement of the cutter mounting plate. A spring biased lever is pivoted to a portion of the can opener frame and operates in accordance with the manual move ment of the cutting element against the end of the can to initiate power-pierce and to maintain the can opener motor on until the end of the can has been sheared therefrom. At this time, the lever pivotally moves to automatically shut off the power to the can opener motor.

A spring biased push button operated latch engages a pin member extending from the hand lever assembly. It permits the removal of same (along with the cutting element carried on the cutter mounting plate) by manipulation of the push button latch structure.

11 Claims, 13 Drawing Figures U I HIT ll P'ATENTEDSEP 12 m2 SHEET 1 (IF 4 7 INVENTOR. Raherf E. McLean BY '4 W PATENTEDSE Zlfl v 3.689.997

" suwanm INVENTOR.

@obem E. McLean PATENIEDSEP 12 m2 SHEET l 0F 4 INVENTOR. Poem E. McLean WWA ELECTRIC CAN OPENER WITH REMOVABLE HAND LEVER AND FRAME ENGAGING PIN ASSEMBLY BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION The basic power-pierce structure and operation common to several prior art can openers has been disclosed in US. Pat. No. 3,078,568 which issued Feb. 26, 1963. Also, the concept of removably attaching a hand lever assembly to the frame of the can opener was discussed in the US. Pat. No. 3,496,635 which issued Feb. 24, 1970 and owned by the same assignee as the subject invention.

My invention relates generally to can openers and refers more particularly to improvements in the construction of electrically operated can openers which may include the power-pierce concept, automatic shutoff, andan easily removable cutter mounting plate which carries the cutting element thereon.

The can opener is comprised of a main frame which is suitably apertured to movably receive a lever assembly. The lever assembly includes the cutter mounting plate, a hand lever, and an interposed plate and spring combination which minimizes the resistance to relative movement between the hand lever and cutter mounting plate. A spring biased power-pierce and automatic shutoff lever is attached to the rear surface of the can opener frame and cooperates with a projection extending from the cutter mounting plate to facilitate in the accomplishment of the aforesaid functions. Similarly, a spring biased pivotal link which is attached to the forward surface of the can opener frame has a movable can guide extending therefrom through a suitable opening in the cutter mounting plate. This can guide moves through an inclined plane in conjunction with the movement of the cutter mounting plate for proper alignment prior to, during and after the severing of the end from the can.

A tapered end stud or pin member extends rearwardly from the hand lever through another alignable opening in the can opener frame for engagement with a push button operated spring biased latch member. This latch releasably engages the abovementioned tapered end stud and either pivotally retains the lever assembly for operative movement on the forward surface of the can opener frame or permits the separation thereof, depending upon the manipulation of the associated push button to move the latch relative to the tapered end stud.

An object of my invention is to provide a power operated can opener having a unique combination of structural and functional features to assure the reliable, efficient operation of same and which can be economically produced. It is an important feature of this object that the can opener will includevpower-pierce, automatic shutoff and removable cutter mounting plate which carries the cutting element thereon.

Another object of my invention is to provide a power operated can opener in which the cutter mounting plate, which carries the cutter element thereon, is fastened to the can opener frame by a single stud or pin member and latch. This object permits the easy removal and reattachment of the cutting element relative to the can opener and minimizes the alignment and associated manual dexterity sometimes required to remove and/or reassemble the can opener component carrying the cutter element thereon.

A further object of my invention is to provide a power operated can opener having a unique structure and operation so as to insure the sensitivity and response to the automatic shut-off condition which occurs when the end has been severed from the can. It is a feature of this object that the subject can opener is constructed to assure that the switch controlling the motive power to the can opener feed wheel remains on when intended and is off at the appropriate time, thereby contributing to the reliability, performance, and users safety of the subject can opener.

A still further object of my invention is to provide in a can opener of the character described, a spring-urged detent means to facilitate and yieldably maintain the hand lever in the optimum rotative position on the can opener frame Since the hand lever is pivotally attached to a cutter mounting plate, reinstallation of the combined cutter mounting plate and hand lever (or the removal thereof) on the can opener frame is facilitated by the above-mentioned spring-urged detent means.

A further object of my invention is to provide, in the can opener of the character described, a uniquely constructed movable can guide which efficiently performs its required function as the can is moved by the can feed wheel but which also is automatically displaceable from its normal operating position to an out-of-theway position when the hand lever is swung upwardly to separate the cutting element from the can feed wheel. Accordingly, either the insertion of the can in the can opener or the removal of an opened can from same is facilitated. Further, the movable can guide will automatically be in its normal operating position whenever the can is engaged in the can opener and/or the cutter mounting plate is being removed from the can opener frame or reinstalled thereon.

Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.

DETAILED DESCRIPTION OF THE INVENTION In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are employed to indicate like parts in the various views:

FIG. 1 is a front elevational view of the upper portion of the can opener embodying the invention;

FIG. 2 is a front elevational view of the upper portion of the frame of the can opener shown in FIG. I with the lever assembly removed therefrom and with a portion of the spring biased link broken away to more clearly show certain cooperating openings in the frame;

FIG. 3 is a rear elevational view of the can opener, the box-like casing having been removed therefrom to expose the interior mechanism;

FIG. 4 is a side elevational view taken from the lefthand side of FIG. 1 with the lower portion of FIG. 1 having been eliminated;

FIG. 5 is a side elevational view taken from the righthand side of FIG. 1 and showing substantially the same portion of FIG. I as that shown in FIG. 4;

FIG. 6 is another front elevational view of the upper portion of the can opener with the hand lever and cutter mounting plate being shown in the positions which they assume to permit the insertion of the can in the can opener and with the broken lines showing the positions of the hand lever and the cutter mounting plate as they are moved into a can piercing position, the broken lines immediately below the cutter wheel represents the upper surface of a can lid;

FIG. 7 is a rear elevational view of the can opener, parts being substantially similar to that shown in FIG. 6;

FIG. 8 is a front elevational view of the upper portion of the can opener with the solid line position of the hand lever and the movable can guide representing the location of same prior to further movement of the hand lever in downward direction and with the broken line position of the hand lever and movable can guide showing the position of same when the spring bias on the link associated with the movable can guide moves same over to its normally operating can flange contacting position;

FIG. 9 is a fragmentary rear elevational view of the combined hand lever, cutter mounting plate, and combination interposed plate and U-shaped spring, with a portion of the hand lever broken away to show the spring and interposed plate in elevation and with portions of same shown in broken lines to more clearly define their contour and shape;

FIG. 10 is a side elevational view taken from the lefthand end of the hand lever assembly shown in FIG. 9;

FIG. 11 is a front elevational view of the frame portion attached immediately to the rear of the front can opener frame; and

FIG. 12 is a sectional view taken generally along the line 1212 of FIG. 3 in the direction of the arrows showing the cutter mounting plate, the associated can opener frames and the switch control rod actuating lever, rod and associated spring; and

FIG. 13 is a sectional view taken generally along the line 1313 of FIG. 9 and showing the can guide structure 30 that pivotally connects the hand lever and the cutter mounting plate.

Turning now more particularly to the drawings, reference numeral generally designates a portion of the frame of the can opener. It should be pointed out that this frame may have several integrally attached frames that cooperate with the can opener mechanisms or it may be a unitary structure'properly molded to accommodate same. As disclosed in my above-mentioned patents, a can feed wheel 21 is threaded onto the can feed wheel drive shaft 22, with drive shaft 22 being journalled in a fixed boss on the forward portion of frame 20 for rotation through suitable reduction gearing (see FIG. 3) by a conventional shaded pole electric motor M. Of course, the frame may be supported from an open front box-like casing so that the above-mentioned frame structure forms at least a portion of the forward wall of the casing.

I have found that frame 20 may be conveniently constructed of a zinc die casting and is provided with four small bosses 23 (FIG. 2) that extend slightly forwardly of the generally vertical surface of the upper left portion of frame 20 in order to provide a seat for the pivoted end of a later described can piercing hand lever 24. A conventional can guard 25 is bolted or otherwise fixedly attached onto the forward surface of frame 20 below feed wheel 21 and operates to maintain the side wall of an engaged can at the desired angle relative to the face of the can feed wheel.

The frame of the can opener (frame portion 20) is apertured near the center of the area confined within the four bosses 23 (see bearing opening 26 in FIG. 2). This opening 26 is suitably sized to receive and rotatively support pin member (or stud) 27 therein. The can piercing hand lever 24 (which forms a part of a lever assembly which will be discussed, infra) is pivotally attached to frame 20. This pivotal relationship is accomplished, in part, by the pin member 27 which extends through a suitable hole (not shown) in hand lever 24 and is hot-headed or otherwise fixedly secured therewithin. The pin member is a hardened part with a tapered rearward end and an annular groove 28 spaced a preselected distance from the rear surface of hand lever 24 (see FIG. 10). As will be described, a retaining latch will be engaged within groove 28 to maintain the can piercing lever 24 firmly seated against bosses 23 when assembled on the can opener frame.

As mentioned above, the hand lever 24 is part of a lever assembly which includes the cutter mounting plate 29 (see FIGS. 1, 9, 10 and 12). Cutter mounting plate 29 is pivoted to the can piercing lever 24 by can guide 30. The flange portion 31 of can guide 30 seats against the forward surface of cutter mounting plate 29 while the reduced diameter tenon portion (see FIG. 13) extends through an aperture in plate 29, through an aligned aperture in an interposed plate (same being interposed between cutter mounting plate 29 and can piercing lever 24), and through the flanged sleeve 33 where the same is finally hotheaded therein to secure all parts in assembly. The reduced diameter portion (not shown) of sleeve 33 extends through a suitable aperture in the can piercing lever 24 to freely pivot the latter with respect to cutter mounting plate 29.

With plate 34 being interposed between cutter mounting plate 29 and can piercing lever 24, the interposed plate is preferably secured to cutter mounting plate 29 by projection welding. The above assembly includes the cutter wheel 35 being journalled on the conventional stud or arbor that is anchored in a suitable boss on plate 29. For convenient construction, cutter wheel 35 may have a limited wobble movement and approximate the cutter wheel shown in FIG. 7 of U. S. Pat. No. 3,314,144, issued Apr. 18, 1967.

The stud heads 36 (see FIG. 4) are interposed between cutter mounting plate 29 and can piercing lever 24 with the tenon portion of the studs extending through holes (not shown) in plate 29 and then hotheaded. The thickness dimension of the heads 36 is substantially the same as the thickness of the interposedplate 34 and provides yet another surface for the forward surface of can piercing lever 24 to move against during the normal operation of same. As a corollary, heads 36 also operate to preclude binding or misalignment and will not contribute significantly to the frictional resistance of the relative movement between the two elements. Finally, free can piercing lever movement is further insured by providing frame 20 with the arcuate recess 37 in frame 20 so that same will freely receive the flanged sleeve 33 of the hotheaded portion of can guide 30 (see FIGS. 2 and 10).

As clearly shown in FIG. 12, the tenon portion 38a of tapered end pin 38 is hotheaded in a suitable opening in cutter mounting plate 29 and extends substantially rearwardly toward and through a rectangular opening 39 in frame 20 (see FIGS. 8, 9, and 12). A substantial portion of rectangular opening 39 (FIG. 2) is surrounded by a forwardly extending boss 40. The upper horizontal surface of boss 40 is positioned to be engaged by a portion of the can piercing lever 24 to limit the downward swinging movement of same to a substantially horizontal position. The boss 40 extends forwardly in close proximity of the cutter mounting plate 29.

The vertical dimension of the rectangular opening 39 in frame is sufficiently greater than the diameter of the tapered end pin 38 to thereby permit the cutter mounting plate 29 to rotate on its pivot (can guide 30 and selected portions thereof) approximately 3 counterclockwise when viewed from the front of the can opener from its normal horizontal rest position.

A substantially U-shaped spring 41 (FIGS. 1 and 9) is freely interposed between cutter mounting plate 29 and can piercing lever 24. One end of spring 41 is provided with a loop 42 while the other end of the spring has an in-turned terminal portion 43 located at the other end thereof. The in-turned terminal end portion 43 extends rearwardly through an opening 44 in lever 24 while the looped portion 42 freely surrounds the tapered head 45 of rivet 46. The tenon portion of rivet 46 extends rearwardly through the suitable opening in can piercing lever 24 and is swaged into a counterbore so as to not extend rearwardly beyond the vertical plane that would be flush with the rear surface of lever 24. The head 45 is tapered to prevent the looped end 42 of spring 41 from accidentally becoming dislodged during the assembly of their respective parts.

The bias of spring 41 reacts to urge the two ends 42 and 43 away from each other. Except when the can piercing lever 24 is swung to any position in which the looped end portion 42 cannot engage plate 34, looped end 42 will normally engage either the

radial edge portions

47 or 48 of plate 34 under a predetermined force. Accordingly, the force of spring 41 yieldably maintains can piercing lever 24 rotatively mounted with respect to cutter mounting plate 29, regardless of any position to which it is moved, whenever the looped end 42 is in engagement with plate 34.

The clockwise rotation of can piercing lever 24 (when viewed from the front thereof) is positively limited by the engagement of the upwardly inclined edge of same with tapered end pin 38, which extends from cutter mounting plate 29, whenever the can piercing lever and cutter mounting plate are removed from the remainder of the can opener. counterclockwise rotation of lever 24 is positively limited (whether or not assembled in the remainder of the can opener frame) by engagement of the hotheaded portion of pin member 27 with the radial edge portion 49 of plate 34.

Frame 20 is further provided with a vertical recess 50 (see FIG. 2) which is appropriately sized and contoured to receive link 51 therein. This pivotally mounted link supports a movable can guide 52 on the lower end portion thereof with same including a head 53 (FIG. 3) at its rearward end portion which extends through a suitable aperture in the can opener frame. The can guide 52 is threaded substantially forwardly of link 51 and permits nut 54 to be tightly received thereon against the forward surface of the link. In actual practice, a sleeve (not shown) will be telescoped over an intermediate diameter portion of can guide 52 with the larger diameter portion of the sleeve seating against head 53. The larger diameter portion 55 of the sleeve seats against the rear surface of the can opener frame in order for the forward surface of head 55 to provide large surface contact with the rear of frame 20 adjacent the aperture through which can guide 52 extends. The intermediate diameter portion of can guide 52 also extends through the above-mentioned opening in link 51 with the nut 54 being tightened on the threaded portion to secure all parts as a unit; Can guide 52 is sufficiently long as is the sleeve having head 55 to permit free movement of link 51 relative to frame 20 and to also maintain the can guide in good perpendicular alignment with the frame at all times. When assembled, the can rim or flange contacting portion of can guide 52 extends forwardly through a suitable opening 57 in cutter mounting plate 29.

A shoulder stud 58 (FIG. 2) is anchored in link 51 slightly above the central portion thereof and extends rearwardly through the lower end 59 of opening 60 in frame 20. The corresponding dimensions of the opening 59 and the diameter of stud 58 is sufficient to permit the link 51 to pivot with respect to frame 20 on stud 58.

Another shoulder stud 61 is anchored in the upper portion of link 51 slightly to the right of shoulder stud 58 and extends rearwardly and freely through the opening 60 in frame 20. The rearward end portion of stud 61 has an annular groove (not shown) that permits one end of tension coil spring 61a (FIG. 3) to be hooked therein while the opposite end of spring 61a is hooked over the boss 61b which extends rearwardly from frame 20 a substantial distance below shoulder stud 61. It will be observed that the force of spring 61a will continually urge can guide 52 downwardly and that this force, in cooperation with the fixed can guide 30, will force the rim or flange of an engaged can downwardly on the teeth of feed wheel 21 thus effecting the required penetration of the teeth into the lower edge of the rim or flange of the can for efficient feeding of the can with respect to cutter wheel 35.

From the above-described structure, it will be clear that shoulder stud 58 pivots the movable can guide assembly relativeto frame 20. The seating of the stud 58 downwardly in the opening 59 of frame 20 limits the downward movement of the can guide 52. Upward movement of the can guide is limited by engagement of the small diameter portion of the sleeve having head 55 with the top of the opening 56 in frame 20, however, can guide 52 is never moved upwardly to such a frame contacting position in the operation of the can opener. Swinging of the can guide 52 is accordingly limited by engagement of the sleeve having head 55 with either the right or the left sides of opening 56 in frame 20.

The rear side of frame 20 is suitably embossed to permit the mounting of a spring biased vertical latch similar to that disclosed in US. Pat. No. 3,496,635, issued Feb. 24, 1970. The latch L seats on the rear vertical surface of the upper boss 62 and the lower boss 63 (as shown in FIG. 4). The boss 64 (see FIG. 3) extends rearwardly from the can opener frame and is engaged by the left edge of latch L and reacts to maintain said latch L in a suitable position for re-engagement with the annular groove 28 in pin member 27 at any time Finally, the latch L has the push button B extending upwardly therefrom so that at least a portion of the push button will be located exteriorly of the can opener casing and/or frame.

Turning now initially to FIGS. 3 and 7, it may be clearly seen therein that a switch control actuating lever 66 is pivoted to the rear side of frame by the shoulder screw 66a, thereby permitting a limited swinging movement of same. A rearwardly extending boss 67 extends through opening 68 in lever 66 and limits the counterclockwise swinging of same (when viewed from the rear) to a substantially horizontal position. Coil spring 69a has it upper end hooked into opening 69 while the other end of same is hooked in the notch of boss 69b which extends rearwardly from frame 20. Accordingly, the spring 69a biases lever 66 in the abovementioned counterclockwise direction so that the normal rest position for the lever is with the upper horizontal edge of opening 68 contacting the upper surface of rearwardly extending stud 67.

As mentioned above, stud or tapered end pin 38, which is fixedly attached to cutter mounting plate 29, extends rearwardly through the opening 39 in frame 20 but also through a similar shaped opening 70 in lever 66. When all of the above-mentioned parts are in the rest position, the stud or tapered end pin 38 seats downwardly in opening 39 of frame 20, however there will be a few thousandths of an inch clearance between the circumference of pin 38 and the upper side of opening 70 in lever 66 in order to facilitate the removal and reinstallation of the combination cutter mounting plate and can piercing lever.

The upper end of a switch control rod 72 is pivoted in the hole 72a in lever 66 while the lower end thereof slidably extends through a suitable bracket 73 secured to frame 20 (FIG. 1) for engagement with the plunger (contact arm) P of switch S which is always spring biased towards the uppermost position. It is contemplated that switch S will be of the normally closed type with the contact points being in engagement with each other and the switch in the on condition unless the contact arm or plunger P is depressed by an external force. The length of switch control rod 72 is such that when the free end of lever 66 seats downwardly on boss 67, the switch will be in the off condition. When the free end of lever 66 is swung upwardly by stud 38 a predetermined distance (well before the stud or pin 38 engages the top side of opening 39 of frame 20), the switch S will be in the on condition with suitable overtravel in both directions. Of course, the tension of spring 69a must be adequate to not only overcome the relatively small force of the spring internal of switch S that urges the button or plunger P upwardly but must also be adequate to rotate cutter mounting plate 29, when the can is engaged in the can opener and the end has been completely sheared therefrom, to effect the automatic shutoff of motor M.

OPERATION The manner of operation of the latch L with respect to 27 is substantially similar to that described in US. Pat. No. 3,496,635. The advantages associated with the single stud and latch are recited in detail therein and, as it refers to the latch engagement of a rotating stud or pin member, it does not substantially differ in content and/or operation. It is significant to note, however, that with the latch described in the instant specification and the US. Pat. No. 3,496,635, supra, the wedging action of the rise cams on latch L will draw the stud or pin member 27, which is anchored in the can piercing lever 24, rearwardly. Inasmuch as pin member 27 is approximately centered within the area bound by the four above-described bosses 23 on frame 20, can piercing lever 24 will always be drawn snugly against the forward vertical surfaces of the bosses, thereby providing good alignment. With pin member 27 positioned within opening 26 in frame 20, the lever assembly including can piercing lever 24 and cutter mounting plate 29 remains in contact with the above-mentioned bosses 23 when the lever is, swung to any of the possible operating positions.

Since the cutter mounting plate 29 is pivoted to can piercing lever 24 by the fixed can guide 30, good alignment between cutter mounting plate 29 and the lever 24 is provided by snugly (but freely) interposing plate 34 and the heads 36 of their associated studs 36a therebetween. The heads 36 and plate 34 remain in engagement with the outer surface of can piercing lever 24 when same is swung to any possible operating position.

The vertical boss 40 can either be adjacent or slightly rearwardly of the right-hand edge of cutter mounting plate 29 when viewed from the front. As shown, engagement of the vertical right-hand edge portion of can piercing lever 24 with the upper surface of boss 40 of frame 20 limits the downward swinging of lever 24 to approximately a horizontal position. Upward swinging of can piercing lever 24 is limited by the engagement of the hotheaded portion of stud or pin member 27 with the heel'or radial edge surface 49 of plate 34.

The clockwise swinging of the cutter mounting plate 29 (as seen in the front view) is limited by the engagement of the tapered end pin 38 with the bottom of the rectangular opening 39 in frame 20 (through which it extends), and counterclockwise swinging of plate 29 is limited by the engagement of pin 38 with the top of opening 39.

The movable can guide 52 is entirely free of cutter mounting plate 29 at all times, except when the can piercing lever 24 is being swung. (This facilitates the efficient functioning of the automatic shutoff feature of the invention.) It is also necessary to displace can guide 52 from its normal operating position whenever can piercing lever 24 is swung upwardly, thereby moving cutter mounting plate 29 substantially to the right (FIG. 6).

When the movable can guide 52 is in its extreme left position (operating position), the shoulder stud 58 anchored in link 51 will be directly above it. (It should be noted that movable can guide 52 will be substantially upwardly, against predetermined tension of its spring 61a, by its engagement with the top of the rim or flange of a can engaged in the can opener.) However, stud 61 (also anchored in link 51 and having the upper end of spring 61a attached thereto) is substantially out of line with can guide 52 and stud 58. Accordingly, the force of the tension spring 61a will not only urge the movable can guide 52 downwardly but will also urge it to the left. This spring bias and coincident can guide urging is supplemented by friction between the top of the rim or flange of the engaged can with the movable can guide 52 thereby insuring that the can guide is always free of the perimeter of the opening 57 in cutter mounting plate 29 (through which it extends) during the operation of the can opener.

As previously stated, the can guides 30 and 52 cooperate to urge the rim or flange of the engaged can downwardly on the teeth of the can feed wheel 21 and the can guard 25 maintains the side wall of the engaged can at the desired angle relative to the face of the can feed wheel 21. The axis of can guide 30 is somewhat to the right and below the axis of pin member 27 (front view). During the operation of the can opener, can piercing lever 24 will remain in the horizontal position even though can guide 30 is positioned somewhat to the right of the stud or pin member 27. Such positioning of these parts minimizes the amount of rotation required for can piercing lever 24, in contrast to rotation requirements if the axis of can guide 30 were directly beneath stud or pin member 27. In a similar manner, the amount of lateral movement of cutter mounting plate 29 is decreased.

With the free end of the motor controlling switch actuating lever '66 normally being urged to seat downwardly with the upper horizontal edge of opening 68 contacting rearwardly extending frame boss 67 due to the force of tension spring 69a, it is significant to note that the force of the spring 69a is not sufficient to prevent the right end of cutter mounting plate 29 (front view) from moving upwardly as intended. Further upward movement of cutter mounting plate 29 is prevented by engagement of the tapered end pin 38 with the upper horizontal edge of opening 39 in frame in the following conditions: (I) when can piercing lever 24 is swung downwardly and cutter wheel 35 seats on the end of the engaged'can; or (2) while the end of the can is being sheared by the cutter wheel. The force of spring 69a, however, must be adequate to move tapered end pin 38 downwardly until it nearly seats on the lower horizontal edge of opening 39 in frame 20 when the end has been completely sheared from the engaged can by cutter wheel 35. This required spring force will also maintain pin 38 nearly seated on the lower edge of opening 39 whenever a can is not engaged in the can opener. As previously stated, whenever force of spring 69a can move or maintain the free end of lever 66 so that the upper edge of opening 68 thereof seats downwardly on boss 67, the switch S and motor M will be in the off condition.

As pointed out in my US. Pat. No. 3,314,144, issued Apr. 18, 1967, the providing of a reliable shutoff means depends on attainment of good differential between the following conditions:.(l) Force required to rotate the cutter mounting plate 29 clockwise (as viewed from the front of the can opener) between its two extreme positions while the end of an engaged can is being sheared by the cutter wheel 35 (during which time resistance of the end of the can to shear by the cutter wheel exists), and (2) force required to so rotate the said cutter mounting plate 29 clockwise (as viewed from the front of the can opener) between such two extreme positions after the end of an engaged can has been completely sheared from the can (when the resistance of the end of the can to shear by the cutter wheel 35 has ceased to exist). It, therefore, may be seen that minimizing the friction between the affected parts is of the utmost importance in order to create a maximum differential between the two conditions. The greater the differential between the two limiting. conditions, the greater the tolerance that can be given to tension spring 69a for effecting the automatic shutoff and the greater the assurance that the switch of the can opener will always be on when intended and will always be turned and remain off at the appropriate time. Inasmuch as cutter mounting plate 29 has only pivotal movement (same being pivoted by can guide 30 to can piercing lever 24) and with the friction between the two parts (mounting plate 29 and lever 24) having been minimized, an exceptionally good differential has been achieved for positive control over the switch S and motor M.

To prepare the can opener to receive the can, the can piercing lever 24 is first swung counterclockwise to its extreme position represented in solid lines in FIG. 6. This lever movement moves the cutter wheel 35 from its overlapping condition with respect to feed wheel 21 to a separated condition in which the cutter wheel 35 will be upwardly and to the right with respect to the above-mentioned overlapping condition. Can guide 30 will also be swung upwardly and to the right. The engagement of movable can guide 52 with the left-hand contoured edge portion of opening 57 (located in cutter mounting plate 29) results in automatically swinging can guide 52 upwardly and to the right on the pivot shoulder stud 58 as the cutter mounting plate 29 is correspondingly moved.

The can (the end or lid of same being shown only by the broken lines in FIG. 6 and represented by the capital letter C) may now be inserted in the can opener in the usual manner so that the flange or rim of the can will be over the toothed portion of feed wheel 21, with the end or lid of the can bearing upwardly against the cutting edge periphery of cutter wheel 35. After the can is so engaged, the can piercing lever 24 is swung clockwise (FIG. 1) to its extreme position, which is the full down position shown in solid line in FIG. 1. As will subsequently be made clear, it is not necessary for the user to continue holding can piercing lever 24 in such a position. Instead, he can remove his hand from the lever and turn to other affairs until such time as he elects to remove the can from the device. The motor of the can opener will be automatically shutoff after the lid has been completely sheared from the can; however, the can opener will continue to retain the can in the engaged condition until such time as the can piercing lever 24 is manually swung back to the starting position.

It will be seen that during the downward swinging of can piercing lever 24 several reactions occurred with respect to the described components of the can opener. For instance, cutter wheel 35 fulcrumed on the end of the can as the under edge of the rim or flange of the can firmly seated on the teeth of feed wheel 21. Additional downward swinging of lever 24 caused cutter mounting plate 29 to rotate counterclockwise on its pivot (can guide 30,), thereby moving tapered end pin 38, against the force of tension spring 69a, upwardly to an upward seating position in opening 39 of frame 20. Simultaneously, switch S changed from its off condition to its on condition, thusly starting motor M and feeding of the can with respect to cutter wheel 35.

Immediately after motor M has been turned on, the cutter wheel has not yet pierced-the end of the can. Additional downward swinging of lever 24 causes cutter wheel 35 to pierce the end of the can as same is being simultaneously fed by the movement of feed wheel 21, thereby accomplishing the power-pierce feature. Such additional movement or downward swinging of lever 24 also moved movable can guide 52 to a location near its leftmost position (front view). Can guide 52 was actually moved the slight additional distance to its leftmost position by the action of spring 61a and the friction between can guide 52 and the rim or flangeof the can. Furthermore, can guide 52 was moved substantially upwardly, against the tension of spring 61a, to a properly aligned position with respect to fixed can guide 30 for providing the required downward force on the upper edge of the rim or flange of the can to effect the efficient feeding of same.

When the end has been completely sheared from the can, the force of spring 69a, operative on pin 38, will move same from its uppermost position in opening 39 to its lowermost position, thereby simultaneously changing switch S from its on condition to its off condition. It should be noted that even though motor M has been turned off, the can opener continues to hold the can. At such time as the user elects, the opened can may be removed from the can opener by holding same and swinging can piercing lever 24 upwardly to its extreme position. Although it is not necessary, the user will normally swing lever 24 downwardly to its extreme horizontal position for rest or storage purposes.

To remove cutter mounting. plate 29 (and can piercing lever 24 which is permanently attached thereto) for cleaning of the cutter wheel, etc., it is necessary only to fully depress the latch push button Band then grasp the cutter mounting plate (preferably at its two vertical edges) and pull the plate forwardly. Can piercing lever 24 should, however, be in approximately the horizontal position before removal of the cutter mounting plate.

The force of tension spring 61a is designed to assure that movable can guide 52 is in its leftmost position (front view) whenever can piercing lever 24 is approximately in the above-mentioned horizontal position. In this position, there is ample clearance between movable can guide 52 and the contoured opening 57 of cutter mounting plate 29. As previously explained, swinging of can piercing lever 24 relative to cutter mounting plate 29 is limited by the engagement of the headed portion of pin member 27 with the heel or radial edge surface 49 of plate 34 when moved counterclockwise and, when removed from the remainder of the can opener, by engagement of lever 24 with tapered end pin 38 when swung clockwise. Of course, the user may swing lever 24 to any possible position relative to the plate 29 when the assembly is removed from the remainder of the can opener.

To facilitate reinstallation of the permanently assembled lever 24 and plate 29 combination on the can opener frame, a spring urged detent means has been provided to easily locate and yieldably maintain lever 24 in a preferred rotative position relative to plate 29 prior to reinstallation. Such spring urged detent includes the U-shape spring 41, the tapered head 45 of rivet 46 and the radial surfaces 47 and 48 of plate 34.

The above-mentioned spring 41 and associated structure includes a rearwardly turned end 43 which extends into an opening 44 in can piercing lever 24 while the looped end 42 of the spring is telescoped over the tapered head 45 of rivet-46 which is anchored in a suitable hole in lever 24. The bias of spring 41 exerts a predetermined frictional pressure against either of the radial surfaces 47 or 48 of plate 34 depending upon which surface the looped end 42 engages. Whenever lever 24 is approximately in the horizontal position, or anywhere between the horizontal position and the extreme clockwise position to which it can be swung when cutter mounting plate 29 is removed from the remainder of the can opener, the looped end 42 will be in engagement with the radial surface 48 of plate 34. As will be noted, although the looped end 42 of spring 41 is moved by the tapered head 45 of rivet 46, the diameter of the tapered head is sufficiently less than the inside diameter of the loop in looped end 42 so as to always permit same to seaton either of the radial surfaces 47 or 48 when in extended radial alignment therewith.

As shown in FIGS. 1 and 9, there is a step between the

radial surfaces

47 and 48. Prior to reinstalling the lever assembly on frame 20, it is preferred that the looped end 42 be positioned approximately in the abovementioned step to facilitate the rotative reinstallation of same. This can be easily accomplished by swinging the can piercing lever 24 counterclockwise (front view) from its extreme clockwise position until looped end 42 seats in the step or notch, or by swinging the can piercing lever 24 clockwise from the position in which the looped end 42is not in engagement with either

radial surfaces

47 or 48 until it arrives at the step or notch mentioned above.

The tapered end of pin member 27 (which extends from the hand lever assembly) facilitates the inserting of same in the opening 26 of frame 20. A substantial portion of stud 27 will be engaged in opening 26 before the tapered end of pin 38 arrives at frame 20 to be inserted through rectangular opening 39 of frame 20. When installing (or reinstalling) the lever assembly, opening 57 in cutter mounting plate 29 will clear the movable can guide 52. It will be observed that in the operation of the opening of the can (after the end of the can has been pierced by cutter wheel 35) the looped end 42 of spring 41 will always be in engagement with the radial surface 48 of plate 34 as cutter mounting plate 29 swings to any possible position on its pivot (can guide 30). Accordingly, the detent means incurs only minimal resistance to the swinging of cutter mounting plate 29 on its pivot as automatic shutoff is being accomplished by the tension of spring 69a and this resistance is the result of the friction between the looped spring end 42 and the radial surface 48 of plate 34.

resistance to pivot, any propensity for the can opener to tilt as the can piercing lever 24 is swung upwardly to its extreme position is precluded. However, whenever the lever assembly (lever 24 and plate 29) is removed from the remainder of the can opener and the user endeavors to position the looped spring end 42 at the step or notch between the

radial surfaces

47 and 48 of plate 34, this notched position can be perceptively felt by the user. Notwithstanding that some additional force is required (during the clockwise swinging of lever 24) to cause the looped spring end 42 to rise to the edge surface 47, and to rise from the edge surface 47 to the edge surface 48, such resistance is hardly discernible inasmuch as it occurs simultaneously with the can piercing phase of the can opening cycle. Any resistance encountered in swinging lever 24 clockwise results in very little tendency to tilt the complete can opener due to the more positive control and the mounting structure associated therewith.

In prior art patents utilizing the power-pierce concept, such as in U. S. Pat. No. 3,078,568, the continuance of affected parts remaining in the can shearing condition (and concurrent continuance of the switch in the on condition), after the end of the can has been pierced by the cutter wheel, is dependent on the total lateral force overcoming the total vertical force. Movement of affected parts from the can shearing condition to the automatic shutoff condition (and concurrent change of the switch controlled motor from the on condition to the off condition) is dependent on the total vertical force overcoming the total lateral force.

In the subject invention, no portion of cutter wheel 35 engages the top surface of the rim or flange of an engaged can. Continuance of affected parts remaining in the can shearing condition (and concurrent continuance of the switch in the on condition) isdependent only on the resistance of the end of the can always being adequate to prevent the force of tension spring 69a from swinging the free end of cutter mounting plate 29 downwardly while the end is being sheared from the engaged can. Since the friction between cutter mounting plate 29 and can piercing lever 24 has been minimized (including restriction of movement of cutter mounting plate 29 to solely pivot during accomplishment of the automatic shutofi), a relatively small (in force) tension spring 69a may be used to swing cutter mounting plate 29 from its shearing position to its automatic shutoff position after the end has been completely sheared from the engaged can. In contrast to small (in force) tension springs, it is to be observed that certain prior art automatic shutoff can openers require similar functioning springs of much greater force, to not only accomplish the automatic shutoff but to adequately force the rim or flange of an engaged can (through the grooved diameter portion of cutter wheel) 6 downwardly on the teeth of the can feed wheel for proper traction and to prevent the can shearing periphery of the cutter wheel from riding upwardly on the end of the engaged can instead of shearing the end of the can as intended.

From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove-set forth together with other advantages which are obvious and which are inherent to the structure.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, 1 claim:

1. [n a power operated can opener, the combination therewith of,

an upright frame,

a can feedwheel rotatable about a substantially fixed axis and supported on said frame,

' a motor drivingly connected with said feed wheel,

a switch means connected with said motor and having a motor energized condition and a motor deenergized condition,

a cutter member,

a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spaced from said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said can feed wheel,

an operating lever, one of said operating lever and said frame having a bearing opening therein, the other of said lever and said frame having a pin member extending therefrom and cooperatingly positionable within said bearing opening to pivotally mount said lever on said frame,

means interconnecting said lever with said carrier member whereby the selective pivotal movement of said lever relative to said frame effects movement of said carrier member between said first and second positions,

switch control means for automatically controlling said switch to energize said motor to effect can end cutting when said cutting member is advanced from said first position to said second position, said motor being energized and said can feed wheel being rotated thereby before said carrier member reaches said second position,

resilient means connected with said switch control means to automatically effect the de-energization of said motor when the cutting of the end of the can has been completed, and

a manually operable latch, said latch releasably engaging said pin member to hold said lever adjacent said frame and to permit said lever and said carrier member to be removed from the respective operating positions of same adjacent said frame.

2. The combination as in claim 1 including means for yieldably maintaining said operating lever at a preselected rotative position relative to said carrier member.

3. The combination as in claim 1 including a movable can guide supported from said frame, and means associated with said carrier member for moving said can guide away from said feed wheel when said carrier member is in said first position and moving said can guide toward said feed wheel when said carrier member is moved from said first position toward said second position.

4. In a power operated can opener, the combination therewith of,

an upright frame,

a can feed wheel rotatable about a substantially fixed axis and supported on said frame,

a motor drivingly connected with said feed wheel,

a cutter member,

a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spacedfrom said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said can feed wheel,

an operating lever, one of said lever and said frame having a bearing opening therein, the other of said lever and said frame having a pin member extending therefrom and cooperatingly positionable within said bearing opening to pivotally mount said lever on said frame,

means interconnecting said lever with said carrier member whereby the selective pivotal movement of said lever relative to said frame effects movement of said carrier member between said first position and said second position,

switch control means for automatically controlling said switch means to energize said motor to effect power pierce and can end cutting as said cutter member is advanced from said first position towards said second position to contact, pierce and cut the end from the can, and

5. The combination as in claim 4 including means for yieldably maintaining said operating lever at a preselected rotative position relative to said carrier member.

6. The combination as in claim 4 including a movable can guide supported from said frame, and means associated with said carrier member for moving said can guide away from said feed wheel when said carrier member is in said first position and moving said can guide toward said feed wheel when said carrier member is moved from said first position toward said second position.

7. In a power operated can opener, the combination therewith of,

an upright frame,

a can feed wheel rotatable about a substantially fixed axis and supported on said frame, a motor drivingly connected with said feed wheel,

a cutter member,

a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spaced from said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said feed wheel,

switch control means for automatically controlling said switch means to energize said motor to effect power pierce and can end cutting as said cutter member is advanced from said first position towards said second position to contact, pierce, and cut the end from the can,

resilient means connected with said switch control means to automatically effect the de-energization of said motor when the cutting of the end of the can has been completed, and I a manually operable latch, said latch releasably engaging said pin member to hold said lever adjacent said frame and to permit said lever and said carrier member to be removed from the respective operating positions of same adjacent said frame.

8. The combination as in claim 7 including means for yieldably maintaining said operating lever at a preselected rotative position relative to said carrier member.

9. The combination as in claim 8 wherein said maintaining means includes a plate interposed between said lever and said carrier member, a spring, said spring having one end portion thereof connected with said lever, another end portion of said spring yieldably contacting a portion of said interposed plate when said lever is in a preselected rotative position relative to said carrier member thereby permitting said lever to be temporarily maintained at selected rotative positions relative to said carrier member.

10. The combination as in claim 9 wherein said interposed plate has a notch defined therein, said lever being rotatable with respect to said carrier member to locate said spring in a position having a portion thereof received within said notch, said lever position corresponding to said spring and notch received condition facilitating the relocation of said hand lever and carrier member in their respective operating positions adjacent said frame.

11. The combination as in claim 7 including a movable can guide supported from said frame, and means associated with said carrier member for moving said can guide away from said feed wheel when said carrier member is in said first position and moving said can position.

Claims

1. In a power operated can opener, the combination therewith of, an upright frame, a can feed wheel rotatable about a substantially fixed axis and supported on said frame, a motor drivingly connected with said feed wheel, a switch means connected with said motor and having a motor energized condition and a motor de-energized condition, a cutter member, a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spaced from said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said can feed wheel, an operating lever, one of said operating lever and said frame having a bearing opening therein, the other of said lever and said frame having a pin member extending therefrom and cooperatingly positionable within said bearing opening to pivotally mount said lever on said frame, means interconnecting said lever with said carrier member whereby the selective pivotal movement of said lever relative to said frame effects movement of said carrier member between said first and second positions, switch control means for automatically controlling said switch to energize said motor to effect can end cutting when said cutting member is advanced from said first position to said second position, said motor being energized and said can feed wheel being rotated thereby before said carrIer member reaches said second position, resilient means connected with said switch control means to automatically effect the de-energization of said motor when the cutting of the end of the can has been completed, and a manually operable latch, said latch releasably engaging said pin member to hold said lever adjacent said frame and to permit said lever and said carrier member to be removed from the respective operating positions of same adjacent said frame.

4. In a power operated can opener, the combination therewith of, an upright frame, a can feed wheel rotatable about a substantially fixed axis and supported on said frame, a motor drivingly connected with said feed wheel, a switch means connected with said motor and having a motor energized condition and a motor de-energized condition, a cutter member, a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spaced from said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said can feed wheel, an operating lever, one of said lever and said frame having a bearing opening therein, the other of said lever and said frame having a pin member extending therefrom and cooperatingly positionable within said bearing opening to pivotally mount said lever on said frame, means interconnecting said lever with said carrier member whereby the selective pivotal movement of said lever relative to said frame effects movement of said carrier member between said first position and said second position, switch control means for automatically controlling said switch means to energize said motor to effect power pierce and can end cutting as said cutter member is advanced from said first position towards said second position to contact, pierce and cut the end from the can, and a manually operable latch, said latch releasably engaging said pin member to hold said lever adjacent said frame and to permit said lever and said carrier member to be removed from the respective operating positions of same adjacent said frame.

7. In a power operated can opener, the combination therewith of, an upright frame, a can feed wheel rotatable about a substantially fixed axis and supported on said frame, a motor drivingly connected with said feed wheel, a switch means connected with said motor and having a motor energized condition and a motor de-energized condition, a cutter member, a carrier member for said cutter member, said carrier member supported for movement between the first position in which said cutter member is sufficiently spaced from said feed wheel to permit insertion and removal of a can rim therebetween, and a second position in which said cutter member is in a cutting relationship with said feed wheel, an operating lever, one of said lever and said frame having a bearing opening therein, the other of said lever and said frame having a pin member extending therefrom and cooperatingly positionable within said bearing opening to pivotally mount said lever on said frame, means interconnecting said lever with said carrier member whereby the selective pivotal movement of said lever relative to said frame effects movement of said carrier member between said first position and said second position, switch control means for automatically controlling said switch means to energize said motor to effect power pierce and can end cutting as said cutter member is advanced from said first position towards said second position to contact, pierce, and cut the end from the can, resilient means connected with said switch control means to automatically effect the de-energization of said motor when the cutting of the end of the can has been completed, and a manually operable latch, said latch releasably engaging said pin member to hold said lever adjacent said frame and to permit said lever and said carrier member to be removed from the respective operating positions of same adjacent said frame.

11. The combination as in claim 7 including a movable can guide supported from said frame, and means associated with said carrier member for moving said can guide away from said feed wheel when said carrier member is in said first position and moving said can guide toward said feed wheel when said carrier member is moved from said first position toward said second position.