US3585717A - Combination can opening and knife sharpening appliance - Google Patents

Abstract

A COMBINATION CAN OPENING AND KNIFE SHARPENING APPLIANCE UTILIZING AN INTEGRAL PLASTIC FRAME MEMBER FOR SUPPORTING AN ELECTRIC MOTOR AS WELL AS THE CAN OPENING AND KNIFE SHARPENING MECHANISM. A COVER MEMBER COOPERATING WITH THE PLASTIC SUPPORTING FRAME TO FORM A HOUSING ENCLOSURE WITH A THRUST BEARING FOR THE SHAFT WHICH SUPPORTS THE KNIFE SHARPENING ABRASIVE WHEEL.

Description

COMBINATION CAN OPENING AND KNIFE SHARPENING APPLIANCE Filed April 8, 1968 June 22, 1971 5, B|ELAK ETAL 2 Sheets-Sheet I.

Z/we. 1 1.10115 l 3 d W1 aw June 22, 1971 5 BlELAK EFAL 3585.117

COMBINATION CAN SEEKING ARE) KNIFE SHARI'ENING APPLIANCE Filed April 8, 1968 2 Sheets-Sheet 2 United States Patent i 3,585,717 COMBINATION CAN OPENING AND KNIFE SHARPENING APPLIANCE Sigmund H. Bielak, Downers Grove, and Stanton A.

Johnson, Homewood, Ill., assignors to Sunbeam Corporation, Chicago, Ill.

Filed Apr. 8, 1968, Ser. No. 719,635 Int. Cl. B67b 7/38 US. Cl. 30-4 8 Claims ABSTRACT OF THE DISCLOSURE A combination an opening and knife sharpening appliance utilizing an integral plastic frame member for supporting an electric motor as well as the can opening and knife sharpening mechanism. A cover member cooperating with the plastic supporting frame to form a housing enclosure with a thrust bearing for the shaft which supports the knife sharpening abrasive wheel.

BACKGROUND OF THE INVENTION As the electric can opener has developed into one of the more popular household appliances, there has been an attempt by manufacturers to reduce the costs of such appliances to a minimum and at the same time increase their versatility. As illustrative of this trend toward increasing the versatility of the appliance, it is noted that the large percentage of the can openers now sold also include means for sharpening knives. Although initial attempts at integrating the knife sharpener mechanism with a conventional can opener were crude and somewhat makeshift, the present day combination appliances are effective from a functional standpoint and are attractively styled. In most instances, however, the knife sharpening mechanism has complicated the structure considerably and added much to the cost of the appliance. One example of such a combination appliance for opening cans and sharpening knives is shown in Bodle Pat. No. 2,897,637.

An approach to lowering the cost of the can opener itself is disclosed in Chambers et al. Pat. No. 3,360,853 which is assigned to the same assignee as the instant invention. In the Chambers et al. patent there is shown a can opener having the electric motor therefor, the reduction gearing, the can rotating means and the can cutting means all supported on a frame member made of injection molded plastic. This integral frame member also serves as part of the housing for the appliance thereby substantially reducing the cost as compared to can openers having mechanism supporting frames in addition -to housing members. The use of the injection molded frame member also provides the advantage of eliminating the need for electrical insulation in some areas and making it easy to provide a double insulated appliance. In view of the cost advantages flowing from the use of the construction disclosed and claimed in Chambers et al. patent, it would be desirable to utilize a similar approach in a combination can opener and knife sharpener.

SUMMARY OF THE INVENTION Accordingly, the invention is directed to a combination can opener and knife sharpener in which an injection molded plastic frame member is utilized to support the elements of the electric motor, the reduction gearing for the can opener, the can rotating and can cutting portions of the can opener and the shaft which supports the knife sharpening abrasive wheel. The housing member which cooperates with the supporting frame to form a housing enclosure for the entire mechanism includes slots for orienting the knife blades with respect to the abrasive 3,585,717 Patented June 22., 1971 wheel as well as thrust bearing means adapted to engage the end of the knife sharpening wheel supporting shaft.

It is an object of the present invention to provide an improved combination can opener and knife sharpening appliance.

It is a further object of the present invention to provide a combination can opener knife sharpener having a low cost design in which all of the functional elements of the appliance are mounted in a single injection molded frame member.

It is another object of the present invention to provide a low cost can opener knife sharpener having a vertically extending frame member which supports all of 'the elements of the appliance and having a cover which cooperates with the frame member to form a housing enclosure for the elements of the appliance and includes a thrust bearing for the knife sharpener shaft.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the invention, reference should be made to the following detailed description when taken in conjunction with the drawings, in which:

FIG. 1 is a perspective view of a combination can opening and knife sharpening appliance embodying our invention;

FIG. 2 is an enlarged fragmentary sectional view taken substantially on line 22 of FIG. 1;

FIG. 3 is a vertical sectional view taken substantially along line 3-3 of FIG. 1;

FIG. 4 is a fragmentary sectional view taken along line 44 of FIG. 3; and

FIG. 5 is a fragmentary view taken substantially along line 55 of FIG. 3.

Referring to FIG. 1 of the drawings, there is shown a combination can opening and knife sharpening appliance referred to generally by reference numeral 11. The appliance 11 is made up of a front housing member 12 and a rear housing member 13. The front housing 12 serves as a supporting frame member and carries all of the functional elements of the can opener in accordance with the teachings of the aforementioned Chambers et al. Pat. No. 3,360,853 as will be explained more completely below. Member 12 includes a base portion 14 and an upright portion 15 which carries at its upper end the can opening mechanism 16 including a can rotating wheel 17 and a can cutting wheel 18.

As is conventional in can openers of this type, the can cutting wheel 18 is mounted for movement relative to the can rotating wheel 17 so that the wheels may be moved apart from the position shown in FIG. 3 in order to insert the end seam of a can therebetween. When the wheels 17 and 18 are returned to the position shown in FIG. 3, the cutting wheel 18 will puncture the cover of the can. To accomplish this relative movement of the wheels 17 and 18, the can cutting wheel 18 is supported on-a hub 19 which is journaled in the supporting frame 12 for rotation about a horizontal axis. The can cutting wheel 18 is mounted eccentrically with respect to the axis of rotation of the hub 19 so that upon rotation of the hub 19, the cutting wheel 18 is moved upwardly from the position shown in FIG. 3.

Connected to the hub 19 within the housing formed by members 12 and 13 is a radially extending lever 20 which extends outwardly through a slot 21 to a position outside of the housing. The outer end of the lever 20 is formed with a handle 22 which is intended for manual actuation to move the cutter 18 from its raised or can receiving position to its lower position, shown in FIG. 3, in which the cutting wheel 18 punctures the lid of the can.

Also supported on the upper end of the supporting frame 12 is a lid retaining magnet assembly 23 which includes a permanent magnet 24. The magnet 24 is loosely supported by a carrier which is pivotally connected at its inner end to the supporting frame 12. On the underside of the carrier 25, there is a camming arm 26 which is engaged by the cutter wheel 18 to pivot the carrier 25 upwardly when the cutting wheel 18 is moved to the can loading or raised position. In this manner, the magnet 24 is positioned to engage and grip the cover of a can as it is severed; and when the cutting wheel 18 is raised on completion of the can cutting operation, the lid is raised upwardly along with the carrier 25 and the magnet 24.

- The can rotating wheel 17 is adapted to be driven by an electric motor 27 in order to rotate the can during the cutting operation. Thus, with the cutting wheel 18 in piercing engagement with the lid of the can, the can rotating wheel 17 which has a serrated or toothed periphery causes the can to turn about its axis thereby forming a continuous circular cut in the cover adjacent the end seam of the can.

It is desirable to rotate the can at a relatively slow speed and it is also desirable to permit the use of as small a motor as possible. Accordingly, it is conventional to include reduction gearing 28 to drivingly interconnect motor armature shaft 31 with a can rotating wheel supporting shaft 32. The shaft 32 is journaled directly in the injection molded plastic frame 12 by means of an elongated boss 33. Immediately adjacent the outer end of boss 33 is a spur gear 34 which is secured to the end of shaft 32.

The armature shaft 31 is formed at its outer end with a worm 35 which engages worm gear 36 as is best shown in FIGS. 2 and 5. The worm gear 36 is formed integrally with a small spur gear 37 with the assembly being supported on a shaft 38 which is press fitted into the supporting frame 12. The smaller gear 37 is in driving relation with the gear 34 carried by the end of the can rotating wheel shaft 32. Thus, upon rotation of the armature shaft 31, the can rotating or feed Wheel shaft 32 is rotated at a slower speed by virtue of the connection through the reduction gearing 28 including the gears 36, 37, and 34.

The electric motor 27 includes an armature 40' and a commutator 41 which are carried by the armature shaft 31. The armature shaft 31 is journaled for rotation in a pair of spaced bearings 42 which are supported directly on projections extending outwardly from the supporting frame 12. In addition, the motor includes a field 43 which is attached to the supporting frame 12 and a pair of brush assemblies 44 which are similarly secured to the supporting frame 12. At the lower end of the armature shaft there is provided a fan 45 which draws motor cooling air up through openings 46 and 47 in the housing members 12 and 13 and circulates the air upwardly across the motor 27.

For the purpose of sharpening knives and scissors, the appliance 11 is provided with an abrasive wheel 50* which is mounted within housing enclosure 51 formed by the housing members 12 and 13. The enclosure 51 is divided into a can opener compartment 52 and a knife sharpener compartment 53 by means of a fiber dividing wall 54. The dividing wall 54 is somewhat channel shaped as is evident from FIG. 4 and is retained in position by opposed projections on the housing members 12 and 13. The fiber partition or wall 54 is formed with an opening 55 through which a shaft 56 extends. The shaft 56 is a hollow tubular member and is journaled for rotation on a stub shaft '57 which is press fitted into the supporting frame 12 as is best shown in FIG. 3. The motor cooling air drawn in through openings 46 and 47 is circulated across the motor 27 and discharged through the opening 55 as well as slot 21 for the lever 20. The outward flow of air through opening 55 prevents debris from the knife sharpening operation from entering the can opener mechanism and the motor.

The shaft 56 is formed with an axially extending passageway 56a which is provided with a slight taper so that the mouth of the passageway is slightly larger than the inner end. Received in the mouth of the passageway 56a for a sleeve bearing 58 which supports the inner end of the shaft 56 for rotation on the stub shaft 57. The shaft 57 is dimensioned so that it is in bearing engagement with only the inner end of the passageway 56a as well as the sleeve bearing 58 at the outer end of the passageway 56a. An arrangement is thus provided in which the tubular shaft 56 is mounted so that it has a bearing support at either end thereof.

On the shaft 56 there is secured a sleeve 59 on which the abrasive wheel 50 is received. A friction type sheet metal retainer '60 received on the outer end of sleeve 59 retains the abrasive wheel 50 against axial displacement with respect to the shaft 56. Adjacent the opening 55, the shaft 56 is formed with an annular Wall 56b and a plurality of radially extending fins 56c which tend to prevent powder and abrasive material from the knife sharpening operation from entering into the can opening compartment '52 through the opening 55. The driving connection between the shaft 5'6 and the abrasive wheel 50 is accomplished by means of a helical spring 62 which surrounds the shaft 56 and sleeve 59 and has outer ends in engagement with a pair of washers 63. The spring 62 urges the washers into engagement with the radial fins 56c on the shaft 56 and against the abrasive wheel 50 thereby drivingly coupling the abrasive wheel to the shaft 56 since the abrasive wheel 50 is in turn urged into engagement with the retainer 60. In the event that too heavy a load is applied to the abrasive wheel 50, the coupling slips thereby preventing any overloading or stalling of the motor 27. In addition, it assures that a knife blade will not be ground excessively through too heavy pressure being applied between the knife blade and the abrasive wheel 50.

The rear housing member 13 is formed with a pair of knife receiving slots 65 which are suitably positioned and angled so as to guide a knife blade into proper engagement with opposite faces of the abrasive wheel 50. In addition, the housing member 13 is also formed with a scissors slot 66 which permits a scissors blade to be engaged with the outer sloped radius 67 of the abrasive wheel 50.

Since the application of the knife blade to the inner face of the abrasive wheel 50 causes the shaft 56 to be displaced outwardly, it is necessary that a thrust bearing be provided to prevent outward axial displacement of the shaft 56. In accordance with this object, the outer end of the shaft 56 is formed with a reduced diameter portion 70 which is received within a recess 71 formed in the housing member 13. Within the recess 71 there is received a thrust bearing 72. It should be noted that there is a clearance between the outer diameter of the end portion 70 and the recess 71. Thus, the rear housing member 13 serves no purpose as far as journaling the end of the shaft 56. The stub shaft 57 is of sufficient length and extent to properly journal the shaft 56 as explained above. Accordingly, there is no problem of alignment as far as the positioning of the thrust bearing 72 is concerned. Since the rear housing member 13 is made of a fairly light, flexible plastic material, it would be unsuitable as a support for a journal bearing since it would be almost impossible to maintain tolerances so as to assure good axial alignment between such a bearing and the axis of the supporting shaft 57. By making the shaft 57 long enough, it is necessary only to rely on the housing member 13 as a support for the thrust bearing 72.

The inner end of the abrasive wheel supporting shaft 56 is provided with an integrally molded gear 75 which is in driving engagement with a gear assembly 76. The gear assembly 7 6 which drivingly connects the shaft 56 with the armature shaft 31 is supported for rotation by a stub shaft 77 which is press fitted into the supporting frame 12. The gear assembly 76 includes a spur gear 78 which is driven directly by the worm 35 on the end of the armature shaft 31. In addition, the gear assembly 76 also includes a gear 79 which is in driving engagement with the gear 75 formed on the shaft 56. From an inspection of FIGS. 2 and 5, it may be readily seen that the gears 78 and 36 which are driven by the worm 35 engage opposite sides of the armature shaft 31, thereby tending to balance out the loads which might be placed on the shaft 31 normal to the axis of the shaft. In addition, there is provided a simple and effective means for driving the can opener feed wheel shaft at one optimum speed and the knife sharpening abrasive wheel shaft at a different optimum speed.

By arranging the motor 27 and all the gearing which driving interconnects the armature shaft 31 and the output shafts 32 and 56 on the same supporting frame 12, the problems of assembly and manufacturing tolerances are reduced to a minimum. The gearing is all assembled to and supported by stub shafts which are accurately positioned in the supporting frame 12. Because of the structural requirements of the supporting frame 12, it is made L of phenolic plastic material which is heat and fire resistant. In the interests of maintaining the lowest possible cost, however, the rear housing member 13 may be made of a less expensive plastic material which characteristically would not have the flame retardant qualities required to meet existing safety standards for a housing member enclosing an electric motor. These safety standards require that the motor enclosing portions of an appliance housing be made of materials which will not be destroyed if there is an electrical short in the motor. Through the use of a fire retardant material for the fiber partition 54, however, these safety standards are met without applying the usual fire retardant paint coatings to the interior of the plastic housing 13. It should be noted from FIG. 4 that the fiber partition 54 is somewhat channel shaped so that it cooperates with the supporting frame to form a secondary fire resistant enclosure for the motor 27.

While there has been illustrated and described a single embodiment of the present invention, it will be apparent to those skilled in the art that numerous changes and modifications will occur, and it is contemplated by the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the present invention.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A combination appliance for opening cans and sharpening knives comprising a supporting frame having a base portion and an upright portion, a can opening mechanism including cutting and can rotating means carried by the upper end of said upright portion, an electric motor supported on the lower end of said upright portion, a first gear reduction means drivingly interconnecting said motor and said can rotating means, a stub shaft extending from said upright portion intermediate said motor and said can opening mechanism, an elongated hollow shaft received on said stub shaft and supporting an abrasive wheel adjacent one end thereof, said hollow shaft being formed with a spur gear on the other end thereof adjacent said frame, a second gear reduction means carried by said frame for drivingly interconnecting said motor and said spur gear, a housing member secured to said frame and together with said frame forming an enclosure for said motor and said first and second gear reduction means, said housing member being formed with a clearance recess to receive one end of said hollow shaft,

. and a thrust bearing in said recess supported by said housing to restrain said hollow shaft against axial displacement outwardly from said frame.

2. The combination of claim 1 wherein said motor has a vertically extending armature shaft with a worm at the upper end thereof, said first and second gear reduction means engaging said worm on opposite sides thereof.

3. The combination appliance of claim 1 wherein said enclosure is divided by a partition of fire retardant material into a can opener compartment and a knife sharpener compartment, said frame being formed of a phenolic plastic material and said housing member being formed of a non-flame retardant plastic material, said motor being enclosed in said can opener compartment, said hollow shaft extending through an opening in said partition to support said abrasive wheel in said knife sharpener compartment.

4. The combination appliance of claim 3 wherein said motor is provided with a cooling fan which draws air in through the bottom of said can opener compartment and exhausts at least a part of said air through said opening in said partition into said 'knife sharpener compartment to prevent debris from knife sharpening from entering said can opener compartment.

5. The combination appliance of claim 3 wherein said tubular shaft is formed with an annular ring obstructing said opening in said partition and radial fins to prevent entrance of the debris from knife sharpening into said can opener compartment.

6. A combination can opener and knife sharpener comprising an upstanding supporting frame made of injection molded plastic, a motor secured to said frame, a can opening mechanism including reduction gearing driven by said motor and supported on said frame, said reduction gearing including gears mounted on shafts carried by said frame, an abrasive wheel for sharpening knives mounted on an elongated tubular shaft driven by said motor, a stub shaft extending from said frame and journaling said tubular shaft, said tubular shaft having a tapered passageway therein to receive said stub shaft, said stub shaft engaging said tubular shaft at the inner end of said passageway and bushing means at the mouth of said passageway journaling the inner end of said tubular shaft with respect to said stub shaft, and gearing carried by said frame to drivingly interconnect said motor with the inner end of said tubular shaft.

7. The combination can opener and knife sharpener of claim 6 having a cup-shaped housing member cooperating with said frame to form an enclosure for said motor, said reduction gearing and said abrasive wheel, said housing member being made of a material which is deformable by heat at relatively low temperatures while said frame is made of a heat resistant material which is resistant at temperatures as high as might be encountered under conditions of an electrical short circuit in said motor, a channel shaped partition separating said enclosure into a can opener compartment and a knife sharpener compartment, said partition being made of heat insulating fire retardant material and forming a barrier between said motor and said cup-shaped housing member.

8. The combination can opener and knife sharpener of claim 6 having a cup-shaped housing member cooperating with said frame to form an enclosure for said motor, guide slots formed in said housing member adjacent said abrasive wheel to position a knife blade with respect to either of the opposite faces of said wheel, and a thrust bearing carried by said housing member to prevent axial displacement of said tubular shaft.

References Cited UNITED STATES PATENTS 2,570,564 10/1951 Kublin 51--128 2,673,477 3/1954 Davis 51-128 2,897,637 8/1959 Bodle 51-128 3,358,365 12/1967 Carlson 30-4 OTHELL M. SIMPSON, Primary Examiner

Images