US3006070A

US3006070A - Can opener

Info

Publication number: US3006070A
Application number: US855796A
Authority: US
Inventors: Nordquist Ronald Erik Johan
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1959-11-27
Filing date: 1959-11-27
Publication date: 1961-10-31
Anticipated expiration: 1978-10-31

Description

Oct. 31, 1961 R. E. J. NORDQUIST 3,

CAN OPENER Filed Nov. 27, 1959 2 Sheets-Sheet 1 Oct. 31, 1961 R. E. J. NORDQUIST 0 CAN OPENER Filed Nov. 27, 1959 2 Sheets-Sheet 2 2& 12

IN VEN TOR.

3,006,070 CAN OPENER Ronald Erik Johan Nordquist, Summit, NIL, assignor to American Can Company, New York, N. Y., a corporation of New Jersey Filed Nov. 27, 1959, Ser. No. 855,796 7 Claims. (Ci. 30-4) The present invention relates to power driven can openers and has particular reference to such a can opener wherein the opening cut is made in the outside layer of the top double seam in order to provide a reclosure for the opened can.

Recent years have witnessed the development of small motorized can openers suitable for use in the home in order to relieve the housewife of physical labor which is frequently necessary when a hand type can opener is used, and to provide a faster, cleaner opening operation. However, substantially all of these commercially marketed home-type can openers are provided with cutting means which cut the can top adjacent the 'base of the inside wall of the top double seam, so that the severed portion of the can end comprises a flat disc which is entirely unsuited for use as a reclosure.

The instant invention provides an improved motorized can opener wherein the can opening cut is made in the outer layer of the top double seam so that the portion of the can end which is thus severed from the can is provided with an inverted peripheral channel which permits its replacement on the can and thus adapts it for use as a friction type reclosure.

In the conventional can opener wherein the opening cut is made through an unsupported single thickness of can end stock, the cooperating parts of the can opener are so dimensioned that the cutting knife initially completely pierces the can end stock and projects substantially beyond it into the can body to insure that complete severance of the can end is effected in a single rotation of the can body relative to the cutting knife. However, when the can opening cut is made in the outer surface of the double seam, as is done by the can opener of the instant invention, a quite different situation is encountered in that the multi-layered end seam presents a solid backingup surface immediately inwardly of the outer seam layer which is to be cut. As a result, it is undesirable, when initially piercing the seam with the cutter blade, to force the blade inwardly into the seam beyond its outer layer, since to do so would mean that the cutting blade would have to pierce more than one layer of the seam and the first complete 360 cut would have to be made through more than one layer of material. Since many of the present day cans are made from hard tough steel, the pressures necessary to cut through more than one layer of such stock impose a substantial strain on the operating parts of the opener and require a much greater driving force than is necessary to cut through a single layer of stock, with the result that the operating life of the opener would be substantially decreased and the probability of slippage between the can and the driving element of the can opener greatly increased.

On the other hand, it is almost an impossibility to insure that the opening blade will cut through to a depth of exactly one layer of the end seam, and not beyond, since such a cutting depth would have to be controlled to within a few thousandths of an inch, and such control could not be consistently maintained in a light, comparatively inexpensive appliance. In addition, variations in can stock thickness and temper preclude completely uniform depth of penetration in all cans.

The present invention solves this problem by providing a novel can opener designed to effect the opening oper- 3,006,070 Patented Oct. 31, 1961 ice ation in more than one rotation of the can so that the initial depth of penetration is not critical. To attain this result, a strong compression spring is interposed between the cutting wheel and the element which applies the piercing and cutting pressure to it. This compression spring is preferably made adjustable so that the pressure exerted against the cutting wheel is suflicient to cause it to initially pierce to a depth which is slightly less than or approximately equal to the thickness of the seam layer to be cut through. Since the compression of the spring results in the application of a constant pressure against the cutting wheel during the entire cutting operation, the cutting wheel is forced more deeply into the can end seam on each successive rotation of the can, with the result that the depth of the cut is gradually increased. The cutting operation is continued until the depth of cut is clearly greater than the thickness of the stock of the can end, at which time the cutting operation is terminated by the operator. The length, and thus the compression of the spring are adjustable, and preferably are so adjusted that complete severance is positively obtained in two or three rotations of the can. As a result, complete severance of the end is obtained without imposing too great a strain on the can opening mechanism.

An object of the invention therefore is the provision of a motor driven can opener which cuts into the outer layer of a can body end seam in order that the severed can end contain a channelled marginal portion and is thus adaptable for use as a reclosure for the can body.

Another object of the invention is to provide such a can opener wherein the cutting operation is gradually effected during more than one rotation of the can body to insure complete severance of the can end.

Still another object of the invention is the provision of such a can opener wherein the cutter wheel is pressed against the can end seam under constant spring pressure so that the initial depth of the cut may be comparatively shallow, but is gradually increased during successive rotations of the can body until the outer seam layer is completely out through.

Yet anohter object of the invention is the provision in such a can opener of means for adjusting said spring pressure so that complete severance of the end can be effected in a reasonable number of can rotations.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURE 1 is a plan view of a can opener made according to the principles of the instant invention;

FIG. 2 is a side elevation of the can opener of FIG. 1, the view showing the operating parts of the opener in non-cutting position;

FIG. 3 is a rear elevation of the upper portion of the can opener, as viewed from the right in FIGURE 2 parts being broken away;

FIG. 4 is a view taken substantially along the line 4-4- in FIG. 2;

FIG. 5 is a side elevation of the upper portion of the can opener, the view being similar to that of FIG. 2 but showing the operating parts of the opener in cutting position;

FIG. 6 is an enlarged elevational detail showing the can driving wheel and the can cutting wheel as positioned at the beginning of the can opening operation;

FIG. 7 is a detail similar to FIGURE 6, but showing the same elements as positioned at the completion of the can opening operation; and

FIG. 8 is a fragmentary view of an opened can showing the severed portion of the can end as detached from the can body after the opening operation has been completed.

As a preferred and exemplary embodiment of the instant invention the drawings illustrate a can opener formed with a suitable frame which comprises a base and a supporting column 12 which is provided with a vertical guide bar 14 to maintain a can C, formed with the usual upper end E and end seam S, in vertical position during the opening operation. Attached to the upper end of the column 12 is a motor housing 16 which contains a suitable small electric motor (not shown) which provides the power for driving the can opener. The motor is provided with the usual power cord 18- and onoff switch 20, and is mounted in a horizontally inclined position as best seen in FIG. 2, with the forward end of its drive shaft 22 projecting forwardly of the motor housing 16 and being enclosed by a housing 23. The housing 23 is formed integral with the housing 16 and contains a front bearing for the drive shaft 22, which shaft is provided with a worm 24- which meshes with and rotates a matching worm gear 26 keyed to a second shaft 28 which is oifset from and mounted at right angles to the motor drive shaft 22.

The shaft 28 is disposed in a housing 30 which is integral with the

housings

16 and 23, and is formed with an enlarged head 31 which is provided with a removable sealing disc 32 which comprises an upper bearing for the shaft 28 (see FIG. 1). The lower part of the shaft 28 is journalled in the lower part of the housing 30 and carries at its lower end a tapered drive wheel 36 which is provided with suitable driving teeth or knurls 38 which engage against the innermost layer of the top end seam S of the can C.

A circular cutting wheel 40, formed with a cutting edge 42 and a bottom guide ring 43, is pivotally mounted in Opposition to the drive wheel 36 so that it can be moved toward and away from the end seam S when the can C is positioned in the opener for the opening operation. The cutting wheel 40 is rotatably mounted on a shaft 44 which is secured in and depends from an arm 46 of a rocker unit '48.

The rocket unit 48 is formed with a pair of laterally spaced bearings 50, 52 which are pivotally mounted on a pivot pin 54 which is secured in a bearing 56 formed integral with the vertical housing 30 (see FIG. 4), and is further provided with a second arm 58 which extends forwardly of the pin 54 and is normally urged downwardly by a spring 60, which is interposed between the housing head 31 and the arm 58, to hold the cutter wheel 40 away from the drive wheel 36 in spaced, not-cutting position (see FIG. 2).

The cutting wheel 40 is moved toward the drive wheel 36 and into operative cutting position by an edge cam 62 mounted at one end of a lever 64 which is pivotally mounted on a pin 66 secured in a supporting boss 68 formed integral with the motor housing 16. The other end of the lever 64 is formed into a shaped handle 70 which can be conveniently grasped by the operator of the opener.

The edge cam 62 engages against a cam follower roll 72 which is carried at the forked outer end of an arm 74 which is pivotally mounted on the pivot pin 54- which also carries the rocker unit 48 (see FIG. 4). As best seen in FIGS. 2 and 5, the cam 62 is formed at its low spot (radially nearest to the pin 66) with an arcuate looking node 76 in which the cam roll 72 seats when the lever 64 is in its substantially vertical, non-operative position (as seen in FIG. 2) to lock the lever 64 against inadvertent movement. When a can C is positioned for opening with its end seam S interposed between the drive wheel 36 and the cutter wheel 40 and resting on the guide ring 43, the handle 70 is pulled forward by the operator. This rocks the cam '62 relative to the cam roll 72, thus causing the roll 72 to ride out of the node 76 and along the 4 rising portion 77 of the cam 62, with the result that the roll 72 is thereby forced downwardly until such time as it enters a second locking node 78 of the cam 62, which node is located at the opposite end of the cam 62, there by locking the handle in its fully down, or operative, position, as shown in FIG. 5.

The pressure which the cam 62 thus exerts against the cam roll 72 is transmitted to the rocker member 48 through a heavy adjustable compression spring 79 which is mounted in a barrel-type seat 80 formed at the outer end of arm 46 of the rocker unit 48 beyond the cutter wheel shaft 44. The upper end of the spring 79 engages against a rounded nose 81 formed in the arm 74 immediately below the cam roll 72, while the lower end of the spring 79 engages against a disc 82 (see FIG. 2) which is positioned at the bottom of the spring seat 80 and is secured to a threaded stem 8-4 which extends through the bottom of the spring seat 80 and threadedly engages with in a nut 88 which is affixed to the bottom thereof. The lower end of the stem 84 is slotted so that it can be rotated by means of a screw driver or coin, and thus is movable upwardly and downwardly within the seat 80 to permit adjustment of the compression of the spring 79.

When the handle 70 is in raised position, the spring 79 is under little or no compression. However, as a result of the downward movement of the handle 70, the pressure of the cam 62 is exerted against the spring 79 as a compressive force. Since the spring 79 is much heavier than is the spring 69, the resistance of the latter is easily overcome, and the cutter wheel 40 is rocked forwardly towards the drive wheel 36 and thus engages and pierces the can end seam S. A great deal of prssure is required to actually penetrate the seam S, and it is necessary that the spring 79 be put under substantial compression by the movement of the cam 62 before its resistance to further compression is sufliciently great to cause penetration of the can seam S by the cutter wheel 40.

The actual degree of spring pressure thus obtained is controlled by the depth of the spring seat 80, and this in turn is controlled by the adjustment stem 84 rotation of which in one direction or the other will result in greater or lesser compression of the spring, as the case may be. Such adjustment necessary to effect the desired enetration of the cutter wheel, which preferably is just less than or substantially equal to the full thickness of the outer layer of the seam S, when once made will, of course, suffice for most cans, and need usually be repeated only to compensate for changes in the spring 79 or in the other parts of the opener due to Wear and aging.

As soon as the initial penetration of the outer seam layer has been obtained, the motor of the opener is energized, thereby rotating the drive wheel 36 and causing the can 'C to rotate relative to the opener. As a result, a cut substantially equal in depth to the initial depth of penetration is progressively made in the outer layer of the end seam S. Since the spring 79 is maintained under compression during the cutting operation, it exerts a constant pressure against the cutter wheel which tends to force it towards a drive wheel 36. As a result, each time the can C is rotated relative to the opener the out made in the end seam S is deepened, thereby insuring complete severance of the outer layer of the end seam S.

In most cases, if the initial piercing depth is almost equal to the full thickness of the outer layer of the seam S, two or three full rotations of the can will sufiice to insure complete severance of the end therefrom. An adjustable stop pin 96 mounted in the arm 58, is engageable against a stop lug 92 formed in the housing head 31 to limit the depth of cut.

When complete severance has been obtained, the drive motor is deenergized and the handle 70 is raised to its vertical, non-operating position to release the pressure on the cutting wheel 40 and to permit the spring 60 to disengage the cutter wheel from the can, thereby releasing the can.

Upon removal of the can from the opener, the severed portion of the can end E can be lifted upwardly and detached from the can. As seen in FIG. 8, this detached portion of the can end E contains a vertical wall W and an inverted marginal channel portion P and is quite satisfactory for use as a reclosure to protect the unused portion of the can contents.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinabove described being merely a preferred embodiment thereof.

I claim:

1. A can opener adapted to cut through the outer layer of a can end seam, comprising cutter means engageable against said outer seam layer, spring means for exerting a predetermined pressure against said cutter means when said cutter means are in engagement with said outer seam layer to force said cutter means into said outer seam layer to a depth initially less than the thickness of said outer layer, means for repeatedly rotating said can on its axis to effect a gradually deepening cut in said outer seam layer, and stop means disposed in opposition to said spring means to terminate application of said pressure against said cutter means when said cutter means have cut into said seam to a depth substantially equal to the depth of said outer layer 2. A can opener adapted to cut through the outer layer of a can end seam, comprising in combination cutter means engageable against the outer layer of said seam, cam means for forcing said cutter means at least partly into said outer layer to initiate the formation of a cut in said outer seam layer, driving means for repeatedly rotating said can on its axis to cause said cut to be extended around said can end seam, and spring means interposed between said cam means and said cutting means to maintain said cutting means under constant pressure toward said can end seam during the formation of said out to efiect a gradual deepening of said out until such time as said cut extends completely through said outer seam layer.

3. A can opener adapted to cut through the outer layer of a can end seam, comprising in combination a cutter wheel engageable against said outer seam layer, pressure means for moving said cutter wheel into contact with said outer seam layer, spring means interposed between said pressure means and said cutter wheel, said spring means being under no substantial compression until said cutter wheel contacts said outer seam layer and thereafter being compressed by said pressure means to exert a constant spring pressure against said cutter wheel sufficient to force said cutter wheel at least partly into said outer seam layer, and driving means for repeatedly rotating said can end seam relative to saidcutter wheel to produce a gradually deepening cut in said outer seam layer until said layer is completely cut through.

4. A can opener adapted to cut through the outer layer of a can end seam, comprising in combination a pivotally mounted rocker unit, a cutter wheel mounted on said rocker unit, a compression spring mounted in said rocker unit, cam means engageable against said spring for rocking said cutter wheel into engagement with said outer seam layer and for compressing said spring to press said cutter wheel against said layer under constant spring pressure, a drive wheel engageable against the inner layer of said end seam, and means for rotating said drive wheel to rotate said can relative to said cutter wheel to efiect a gradually deepening cut in said outer seam layer until said outer seam layer is completely out through.

5. The opener of claim 4 wherein stop means are provided to limit movement of said rocker unit for stopping the inward cutting action of said cutter wheel at a depth substantially equal to the thickness of the first layer of said end seam.

6. The opener of claim 4, wherein said cam means comprises a cam carried at one end of a pivoted arm, and wherein a second pivoted arm is interposed between said earn and said spring, said second arm carrying at its free end a cam roll which is engageable against said cam.

7. The opener of claim 6 wherein said cam is formed with a locking node to lock said cam against inadvertent movement when said cam is in inoperative position, and a second locking node to lock said cam when it is in operative position.

References Qited in the tile of this patent UNITED STATES PATENTS