US2636260A - Can opener - Google Patents

Description

April 8, 1953 D. FARANDATOS 2,636,260

CAN OPENER Filed April 18,1952 5 Sheets-Sheet l D. FARANDATOS 2,636,260

April 28, 1953 CAN OPENER Filed April 18, 1952 5 Sheets-Sheet 2 IN V E VTOR. 05w f2; BAX/0A ms ATTMMFV April 28, 1953 D. FARANDATOS CAN OPENER 5 Sheets-Sheet 3 Filed April 18, 1952 IN VEN TOR. fii/v/a flw/J/vavos April 28, 1953 D. FARANDATOS CAN OPENER 5 Sheets-Sheet 4 Filed April 18, 1952 I N V EN TOR. Df/V/J' fizm/vmms 4 TU/PIVEV April 1953 D. FARANDATOS 2,636,260

CAN OPENER Filed April 18, 1952 5 Sheets-Sheet 5 INVENTOR. DEN/6 fim/vmms Patented Apr. 28, 1953 UNITED STATES PATENT OFFICE Claims.

This invention relates to a can opener and to a method of opening cans.

It has been recognized by the medical profession, by publication in various medical journals, that some stomach and intestinal disorders arise by reason of fine particles of metal cut or torn from the bodies of cans and falling into the food during opening of the can by can openers. These particles of metal are so small as not to be observable in most cases but they are sufiicient to set up material irritation in the lining of the digestive tract and to serve as focal points for the attack of diseases. It is an object of this invention to prevent such particles of metal from entering into the food, and to remove them.

Wherever meals are served en masse, as in restaurants and army camps, hospitals and the like, the quantity of canned foods consumed is great. The problem of handling such foods in a sanitary way is diflicult because the can openers at present employed generally make little provision for sanitation during the opening. For example, the can top drops into the open end of the can after it has been excised, and has to be fished out with the fingers; the tops of the cans are usually dusty and dirty and the submergence of the top after cutting mingles the dust and the dirt with the contents of the can. It is an object of this invention to handle the excised parts of cans, such as tops, so that they will not enter into the food in the can and need not be touched by the fingers of the operator; in restaurants and the like where many cans are to be opened at once, it is customary to open dozens, and even hundreds of cans in sequence without cleaning the can opener. This results in contamination of the later cans by the contents of the earlier opened cans. After the opening has been completed, the can opener is, frequently, not washed, which is conducive to disease. It is frequently not the fault of the operator that this uncleanliness occurs, because the design of the can opener does not facilitate easy washing.

It is an object of this invention to provide a can opener with a readily removable blade which can be removed after each opening and cleaned before the next can is opened. With this can opener, the cleansing operation may be carried out rapidly and does notmaterially increase the time required for opening a can.

' Even though a can opener is provided, as is this one, with a readily removable knife, it is necessary to furnish the operator a reminder to clean the blade. It is an object of this invention' to provide a can opener with mechanism which renders it inoperative, which requires an act on the part of the operator to restore it to working condition, and which reminds the operator to clean the blade.

Can openers have heretofore been produced with magnetized blades but such blades have had a tendency to accumulate the fine particles of metal which are torn from the cans as the cans are opened. As the blades have been used, the metal particles from previous openings are admitted to the contents of the can being opened. It is an object of this invention to provide means whereby the particles of metal held on a magnetized knife may be expelled from the knife, after each operation, and regardless of whether the operator cleans the blade or not. This can opener is provided with an automatic, self-cleaning feature.

Another object of the invention is to expel particles of metal, magnetically caught on a knife blade, from the blade by reversing the polarity of the blade.

A preferred form of the invention is illustrated in the accompanying drawings, wherein v Fig. 1 is a perspective view of the new can opener;

Fig. 2 is a schematic diagram of the new can opener illustrating the principles thereof;

Fig. 3 is a vertical sectional view through the novel can opener showing the parts thereof; this figure is a section on the line 3-3, Fig. l.

Fig. 4 is a horizontal plan view of the base or support of the can opener with the standards shown in section;

Fig. 5 is a detail of the can support tilting mechanism taken from above;

Fig. 6 is a vertical sectional view on the line 66 of Fi 5.

Referring now to the numerals of the drawing, the can opener is provided with a base i which may be attached by screws 5 to any sup port such as the top of a table. This base is provided with vertically arranged sleeves 2 which receive standards 3 which are slidable therein and which carry a head 4. As the standards 3 are slidable in the sleeve 2, the head can be brought down to the base, or elevated atthe will of the operator. In operating the can opener, a can is placed on the base I, the head 4 having been first lifted to a sufficient height to admit the can, the edge of the can is brought against the flanges 6 of rotors l and excision of the can top is begun by driving the knife 6 into the can top by lowering the head 4. 1

The novel principles of the new invention, or.

most of them, are set forth in Fig. 2. Reference will now be had to that figure before proceeding with a detailed description of the structure of the can opener. In this figure, the base i is diagrammatically indicated by a broken line which circumscribes certain parts and the head 5 is indicated by another broken line which circumscribes other parts.

Referring now to Figs. 1 and 3, the can opener has a main frame 9 which is mounted on a horizontal pivot I0 and this frame includes a knife-holder or support H in which the knife 8 is slidably received and held by locking means including a spring-pressed bolt it. By pulling the bolt G2 to the left, in Fig. 3, the knife can be released and instantly removed by simply lifting it out of the holder ii. The bolt is provided with a cam face 13 which allows the operator to insert the knife by a simple downward motion thereof, the bolt being thrust aside by the cam i3 until it is driven by a spring into apertures in the knife and knife holder as shown in Fig. 3.

Another frame member i t is fixed to the standard 3, and not tiltably as is the main frame, and this frame i l furnishes upper and lower bearings 15, it for the rotary shaft ii, which bears at its upper end the pivoted lever V and at its lower end the can-turning gear it. Holder ii and yoke 21 are both fixed to the main frame a. A spring 28 bears against yoke .25 and forces the blade of the knife 8, which is attached to the holder ii, toward the gear it so that the rim of the can is forced against the gear and may be compelled to turn past the knife by rotating the handle it in a horizontal plane. The yoke 2| is attached to and forms a part of main frame 9. A sleeve 22 slidable on the shaft if is moved by a cam 23 when the handle it is raised to elevated position as in Fig. 3 to depress the yoke 2i against the spring 2:: and to move the blade is outward away from the gear i9 so that the rim of a can from which the top has been excised may be freed. Thus far the can-turning and can-cutting means are substantially like the structure which has been heretofore described and claimed in my prior application Serial No. 210,556, filed February 12, 1951. The following are the novel features of my invention:

Means is provided to lock the shaft ll so that it may not be turned except when the knife 3 is magnetized. The upper end of the shaft carries a splined sleeve 2 1, which is keyed thereon, and a locking pin 25, which is attached to a crank 26 and is biased into engagement with the splines by a spring 2?. Spring 2? is shown as a simple coil spring in Fig. 2, and in Fig. 3 is shown as a fiat coil spring applied to the crank 26 at its fulcrum.

The end of the crank 26 is connected to the armature 28 of a solenoid 2! When the sole noid is energized, the armature is drawn down wardly and the pin 25 is withdrawn from the spline 24, freeing the shaft I! so that it can turn the can past the knife 8 and excise the top.

The main frame I l is composed of a magnetizable material such as soft iron, which is readily magnetizable and demagnetiza-ble, and this frame carries a bracket 30 which supports the outer ends of two electromagnets 36, 32. These electromagnets are so wound that their adjacent poles are of opposite polarity; thus, magnet 31 may be conceived as. having anorth pole at its right hand end and magnet 32 as having a south pole at its right hand end.

The adjacent right hand poles of the magnet 31, 32 are connected to the main frame 9 so that they transmit their magnetism through that frame and the holder ii to knife 8. As the magnets are not simultaneously energized, the polarity of the knife 8 will correspond with that of the pole of magnet El, 52 which is energized. Thus, if magnet 3! is energized and if magnet 3! has at its right hand end a north pole, the knife 8 will also have magnetism of north polarity. Conversely, if the magnet 32 is energized, the knife blade 2 will have south polarity. ihe bracket ti! is of copper or some other nonmagnetic material. A bracket 33 of magnetizable material extends from the pole of magnet 55!, or even from the pole of both magnets, into a position Where it is capable of attracting the top of a can which is being opened. In this position, it cooperates with a pole i l to hold the top of the can and to prevent it from falling intov the food. Copper bands to wound around the ends of poles 33 and 34 constitute them shaded poles.

The electrical system for operating these various parts is constructed as follows:

A plug 3% is provided at the end of a lead-in cord 3'1, one Wire of which 38 leads to microswitch 38 which is shown in dotted lines from above in Fig. l and in elevation in Fig. 3. A switch operating pin ii) attached to the head opens the switch 33, when the head is lowered into proximity to the base 1, cutting off all cur* rent to the solenoid and the magnets, so that the spring 2'! thrusts the pin 25 into the spline 2t and prevents the opener from being used. The pin iii enters an opening Aid in the base and engages the switch This apparatus also works to inactivate the apparatus when the plug 36 is not connected to a source of electric power. Before the apparatus can be used, the plug 36 must be inserted in a socket and the switch 39 must be closed. The operator, having been unable to use the instrument, recalls that the instrument must be plugged in, thus making it possible to energize the magnet and to magnetize the knife 8, and at the same time he recalls that the knife should be washed, so, before proceeding further he pulls out the lever 12, removes the knife, cleans it, and puts it back in position. He now raises the head by means of handle i8, closing the switch and allowing current to flow through line switch 33, line M to switch &2 which is of two-way type. In

the position shown in 2, the current flows through the upper blade of the switch and line 43,, line l to solenoid 2-9, and from solenoid 29 through line $5 to return line 3i. The activated solenoid withdraws the pin 25 from the splines 24 so that the shaft if can be turned to rotate a can. At the same time current flows from line 44 to line 56, light t! and through line it to line 45 and return. At the. same time the current continues along line 5-3 to electromagnet 32 and from thence to return line 3?, the knife blade 8 thus being polarized with one polarity. The resistances of the line to the light and the line to the solenoid can be balanced by insert.- ing resistances in, the lines, if desired.

A can is now placed upon the base i' from which projects a switch lever 39, the end of which is engaged with the switch 32;. When the can is placed on the rollers, 7, it depresses the switch lever 49 and shifts the flow of current from line 43 to. lineSD, which con-tinuestovenergize solenoid 29, light 41, but now deenergizes magnet 32 and energizes magnet 3|. The mag,- netised knife 8 is plunged into .the can by a downward stroke of the head, the handle 18 is laid in horizontal position so that the spring 20 causes the blade 8 to press the rim of the can against the gear I9. Rotation of the handle [8 causes the gear 29 to rotate and to turn the can against the edge of knife 8. As the top is removed, the poles 34, 35 attract and hold it, the blade 8 attracts and holds any fine particles which are dislodged from the can, and both the top and the particles remain attached to the head, while the head is lifted until the knife is freed, and then the can may be removed from base I. As it is removed, the switch 49, which extends upwardly at an angle to the base, gradually rises, first disconnecting line 50 before making contact with line 43, thus demagnetizing the poles 34, 35 and allowing the can cover to fall onto the base I. Some of the larger particles may fall from the blade 8 at this time, but the blade is, of necessity, of hard steel and does not lose its magnetism as quickly as poles 34, 35 which are of softer steel. Consequently, some or all of the particles may remain attached to the blade 8 by reason of the residual magnetism thereof. When the lever 49 reaches its fully raised position, contact is made with the line 43 and the magnet 32 is energized, and this acts to reverse the polarity of the blade 8 and to discharge the particles attached thereto.

After the can cover has fallen from the holding magnet onto the base I, it must be removed and this is accomplished by the mechanism shown particularly in Figs. 5 and 6. The upper face of the base I is composed of a plate 5|, which is attached at one side to a U-shaped bracket 52, the central section of which is welded, brazed or otherwise affixed to the plate. The arms of the U-shaped bracket 52 are also U-shaped and are pivoted at their ends to pins 53 which are attached to the base I. A pin 54 is attached to a crank 55 which is pivoted at 56 to the base. The crank 55 is connected at its other end to a draw-bar 51 by means of a pin and slot-connection 58. The draw-bar is connected to a second pin 59 attached to the arm of the bracket 52 at a position off-set from center 53. The lower end of the draw-bar 51 is attached to the frame by a pivot 60 so that the motion of lever 55 against the pin 58 throws the draw-bar toward the right as seen in Fi 6, and elevates the plate 5| by means of bracket 52 around pin 53 as a center. Thus, it is possible to tilt the plate 5! so that the can top will slide OE and into a receptacle provided at the side of the apparatus.

The plate itself is provided with a plurality of raised ridges 6| which reduce the friction of the can as it turns.

An advantage of the invention is that the objects of the invention hereinbefore stated have been accomplished. Another advantage of the invention is that there has been provided a can opener having a removable knife which is partially self-cleaning. Another advantage of the invention is in the provision of an electromagnetic can opener which cannot be operated until it has been magnetically activated. Another advantage of the invention is in the provision of the magnetic can opener which handles the tops of cans without contact with human hands. A particular advantage of the invention is in the self-locking feature. Another particular ad- 6 vantage of the invention is the provision for reversing the polarity of the magnetized knife. Other advantages of the invention and of its construction will be apparent from the description which has preceded and by the claims which follow.

As many apparently widely different embodiments of the present invention may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments.

What is claimed is:

1. A can opener comprising magnetizable cutting means, means associated therewith to magnetize the said cutting means with selected polarity, and means associated therewith to reverse the polarity thereof.

2. A can opener having a cutting means, rotatable means associated therewith to turn a can past the cutting means, magnetizing means associated with the cutting means to magnetize the cutting means, locking means associated with said rotatable means to fix it against turning, magnet means associated with said locking means, and means operable simultaneously to cause said magnetizing means to magnetize said cutting means and said magnet means to unlock said locking means to release said rotatable means.

3. A can opener having a magnetizable cutting blade, an electromagnet magnetically connected to said blade, a can rotor associated with said blade, rotary locking means engaged with said rotor, a solenoid operatively associated with said locking means, and means to simultaneously energize said electromagnetic means and said solenoid to magnetize the blade and to disengage said locking means.

4. A can opener comprising a knife, can rotating means associated therewith including a shaft, a splined sleeve fixed'to the shaft, and means to rotate the shaft, a support having a can rest, means to tilt the can rest, first and second connected switches associated with said support, first switch operating means associated with said support and operable to throw said first switch, second switch operating means associated with the shaft and operable to throw said second switch, means to connect said switches to a source of current, a first electromagnet electrically connected to said first switch and magnetically connected to said knife, a second electromagnet electrically connected to said first switch and magnetically connected with reverse polarity to said knife, said first switch operating means being operable by a can to energize the said first magnet during cutting of the can by the knife and to energize the second said magnet v after removal of the can, a pin biased into locking relation with said splines to prevent rotation thereof, solenoid means operatively associated with said pin to remove it from said splines and connected with said second switch, and a signal light connected with said second switch, said first switch being of two-way type and said second switch being of off-on type.

5. A can opener comprising a knife, can rotating means associated therewith, a first electromagnet magnetically associated with said knife, a second electromagnet magnetically associated with said knife with reverse polarity, first switch means operating to energize said knife with said first electromagnet during the opening of a can, and second switch means operating to deenergize said first electromagnet and aesaaeo to energize said knife. with reverse polarity by said. second eleotromaenet upon removal of an open can.v

6.. A. can opener comprising a I nife, can rotating: means associated therewith including a shaft, a splined sleeve fixed to the shaft, a retractable holt. engaged with the splined sleeve, a solenoid associated with said. bolt, means to lift and rotate the shaft, and means. to energize the solenoid and. retract the. bolt when the. shaft is lifted, and can operated means to magnetiz'e the. knife.

7. A. can opener comprising a knife, can rotating means associated. therewith, locking means. associated with the can rotating means, magnetizing, means associated with the knife, and lock-releasing means. associated with the magnetizing means to release the can rotating means prior to the operation of opening a can.

8. A can. opener comprising, can. opening means incliiding cutting means, means to mag netize the cutting means, means associated with the magnetizing means to render the can opener inoperative, and means to energize the magneti'zing means and to make the can opener operative, simultaneously.

9. A can opener having a blade above a base, a. carisupporting means mounted onthe base beneath the blade, and means to tilt the can supporting means todisplace any object supported thereon.

10, A can opener comprising magnetic cantop holding means, a tiltable platform beneath the said holding means, means associated with the said holding means to drop can tops held by the said top holding means uponthe tiltabl'e platform, and means associated with the base to tilt the base 176- remove can tops dropped thereon by the top holding means.

DENIS FA'R'ANDATOS.

No references cited.

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