US3031751A - Automatic electrically operated can opener - Google Patents

Description

May 1, 1962 F. J. HART AUTOMATIC ELECTRICALLY OPERATED CAN OPENER Filed oct. 14, 1960 5 Sheets-Sheet 1 INVENTOR. FRA/VA J A64/F7' May 1, 1962 F. J. HART AUTOMATIC ELECTRICALLY OPERATED CAN OPENER Filed oct. 14, 1960 3 Sheets-Sheet 2 INVENTOR. ffii/VA JI A4437' BY y May l, 1962 F. J. HART AUTOMATIC ELEcTRcALLY OPERATED CAN OPENER Filed Oct. 14, 1960 5 Sheets-Sheet 3 United States Patent 3,031,751 AUTOMATIC ELECTRICALLY OPERATED CAN OPENER Frank I. Hart, Fairlawn, NJ., assignor to Jay Kay Metal Specialties Corp., Long Island City, N.Y., a corporation of New York Filed Oct. 14, 196), Ser. No. 62,771 11 Claims. (Cl. 30-4) This invention relates to can openers and, more particularly, to electric motor operated can openers.

It is an object of the present invention to provide an electric can opener having various operating features which provide for safe, convenient, and completely automatic operation.

A further object of the present invention is to provide a completely self-contained electrically operated can opener having an exterior housing of attractive design, including a control lever member which is selectively movable into an enclosing position with the operating parts of the can opener to provide an attractive storage position when the can opener is not in use.

Still a further object of the present invention is to provide an automatic can opener of the type described having a yieldable clutch means in the transmission mechanism between the motor and cutting parts which will prevent damage to the operating mechanism in the event that the cutter becomes jammed or otherwise engages an obstruction during energization of the motor.

Still a further object of the present invention is to provide an automatic can opener having a control lever member which also functions as a shield to prevent accidental cutting of ngers during operation of the can opener, and which control lever includes a magnet for lifting the severed end wall of the can to an elevated position upon completion of the opening operation.

An `additional object of the present invention is to provide a control system for an automatic electric can opener of the aforementioned type in which the control lever is automatically movable toward an initial position upon the completion of the cutting operation, so as to deenergize the motor and terminate the cutting operation.

A further object of the present invention is to provide a can opener of the aforementioned type which will readily accommodate cans having walls of dilierent thicknesses, and cans of different sizes and shapes.

All of the foregoing and still further objects and advantages of this invention will become apparent from a study of the following specication, taken in connection with the accompanying drawing, wherein:

FIG. 1 is a perspective view of a can opener made in accordance with the present invention in actual use.

FIG. Z is an enlarged longitudinal cross-sectional view of the can opener shown in FIG. l.

FIG. 3 is a transverse cross-sectional View taken along line 3 3 of FIG. 2.

FIG. 4 is a fragmentary longitudinal cross-sectional View, similar to FIG. 2, showing the parts in an initial position.

FIG. 5 is a transverse cross-sectional View of the parts shown in FIG. 4.

FIG. 6 is a fragmentary rear elevational view of the transmission mechanism of the present invention.

FIG. 7 is an enlarged fragmentaiy front plan view of the cutter blade and drive wheel forming the operating parts of the present invention.

FIG. 8 is a view similar to FIG. 7, showing the drive wheel in an initial retracted position prior to the insertion of the can rim between the drive wheel and cutter blade.

Referring now to the drawing, an automatic electric can opener 10 made in accordance with the present indljl lCC

vention is shown to include a base 12 which can be conveniently constructed of molded plastic material, which base is provided with a pair of rearwardly disposed vertical columns 13, and about which a metallic sheath 15 is formed. A bracket 16 secures the base 12 to the motor which forms a lower extension of a main frame including a face plate `and rear mounting plate, as will be hereinafter more fully described. A plurality of machine screws 18 also secure a cutter `block 19 to an indent in the face side of the sheath 15 and to the face plate 36 forming a part of the main frmne disposed inwardly of the sheath. Additional screws 20 secure the base columns 13 to the rear extremities of the sheath 15, and to a back closure plate 21 which encloses the rear portion of the assembly and serves as a mounting plate for suspending the unit upon a wall, should such be desired.

It will now be recognized that the main o1' supporting structure of the can opener is enclosed on the front and sides by the sheath 15 which, in turn, is connected by the screws 2t) to the rear side of the frame, which screws 20 also connect the rigid mounting plate to the back side of the assembly. The skeletal framework including the plastic base 12, columns 13, and the like, is simply carried by the sheath and supporting structure, and is primarily for decorative purposes. This prevents mechanical stresses and strains set up by the operating mechanism from being transmitted to the molded plastic parts, thus preventing fracture, distortion, or other adverse effects.

A cross shaft 23 extending between the side plates 25 of the main frame which are integral with the face plate 36, are slidably received within slotted guideways Z4 in the top 26 of the molded plastic base 12. It will thus be recognized that by means of a combination plastic base and metallic sheath, a substantially rigid support and housing is provided for the operating parts that are normally completely enclosed therewithin and completely hidden from view.

A drive shaft 30 is rotatably carried upon the sides of a channel-shaped mounting lever 33 that is pivotally secured at its opposite lower end upon a horizontal pulley shaft 35 rotatably carried by the face plate 36 and rear mounting plate 37 of the main frame. The pulley shaft 35 also supports an enlarged pulley 39 and a drive pinion 4Q. A flexible belt 42 drivingly connects the pulley 39 on the pulley shaft 35 with a smaller pulley 43 secured upon the shaft 45 of the electric motor 46. The pinion 40 is in driving engagement with a reduction spur gear 43 rotatably supported upon one end of the drive shaft Si). A torsion spring 49, having one end connected to the drive shaft 30, has an opposite end extending along one side of the spur gear 48 in driving abutment with an outwardly projecting drive tab or stop 51. Thus, in response to energization of the motor 46,

motion is transmitted from the drive shaft 45 to the pulley 43, and thence to the drive pulley 39 through the belt 42. The pinion 4d secured upon the pinion shaft 35 along with the drive pulley 39 transmits power to the spur gear 48 which is rotatably mounted upon the drive shaft 3i?. However, the rotation of the spur gear 48 with the tab 51 in abutment with the terminal of the torsion spring 49, is operative to transmit rotational movement tothe shaft 30.

In the event that the drive shaft 30 becomes jammed for any reason whatsoever, continued limited rotation of the spur gear 43 and tab 51 against the torsion spring 49 may be yieldably resisted by the torsion spring 49, thus partly stressing the torsion spring before the motor is forced to a standstill while still energized. By loading the spring in this manner, it will, upon deenergization of the motor, allow for backward rotation of the entire mechanism, thus enabling the parts to `free themselves.

Also, the spring will absorb any major shocks to the drive mechanism such as caused by hitting a large obstruction on the cam rim, or the like. Another advantage of the spring is to allow the motor to gain speed and momentum upon energization thereof, before engaging the major cutting load, thus allowing for the use of a smaller motor and operating parts.

A drive Wheel 53 is secured to the outermost end of the drive shaft 3d and has a plurality of drive teeth in the vicinity of the cutting blade 54 carried upon the cutter block 19. This blade is detachably mounted upon the cutter block -by means of a screw 55, thus facilitating the replacement or sharpening thereof Whenever required.

It will be noted that an arcuate slot 57 extends through the front face of the sheath and face plate 36 of the main frame, thus accommodating limited arcuate movement of the drive shaft 36 and cutter wheel 53 relative to the cutter blade 54. This slot 57 is normally maintained in a completely closed condition by means of a shield 58 having an arcuate slot 59 extending transversely of the exposed arcuate slot 57. This shield is pivotally supported within the interior of the main frame upon a pivot pin 6i). Thus, as is clearly shown in FGS. 7 and 8, during movement of the driving wheel l53 from the initial position shown in FIG. 8 to the driving position shown in FIG. 7, or vice versa, the slot 57 is completely covered at all times by the shield plate 58.

An L-shaped control lever '65 having a pair of depending legs 66, is rotatably supported upon the crossshaft 23 of the main frame. This control lever 65 is further provided with a depending tail piece 68 having an inclined cam surface 69 which is movable wi-th respect to an edge 71 of the mounting lever 33. Thus, ythe L-shaped control lever 65 is supported for rotation about a transverse axis extending substantially normal to the pivot axis of the mounting lever 33, whereby npward pivotal movement of the L-shaped control lever 65 from a lowered to a raised position is operative to effect arcuate movement of the drive shaft from the engaged position shown in FIG. 7 to the disengaged initial position shown in FIG. 8, against the action of a torsion coil spring 62 mounted upon the pinion shaft and acting between the main frame face plate 36 and the mounting lever 33. Thus, in response to downward movement of the L-shaped control lever 65 from the initial position shown in FIG. 4, to the operating position shown in FIG. 2, the spring 62 is free to rotate the mounting lever 33 to enable the drive wheel 53 to move into'proximity with the cutter blade 54, as shown in FIG. 7, from the disengaged position shown in FIG. 8.

The uppermost extremity of the cam surface 69 of the control lever tail piece 68 is provided with an indent 73 which receives the edge 71 of the mounting lever 33 in the uppermost elevated position of the control lever 65 thus tending to serve as a detent for releasably securing the control lever in the elevated position and for securing the mounting lever 33 in the rotated position against the action of the torsion spring 62. This facilitates the loading of the can to be opened, without requiring the use of one hand to secure the control lever in the elevated position.

A dielectric plate 76 secured upon one of the legs 66 of the control lever 65 has a dwell surface 77 which engages with a projection 78 upon a movable contact arm 80 of a pair of switch contacts 81 that control energization of the motor 46. The shape of the plate 76 is such that the dwell surface 77 will engage the projection 73 only in an intermediate operating position of the control lever 65. An over-center torsion spring 83 acting between the main frame and the control lever 75 acts upon the control lever 65 in its centered operating position shown in FIG. 2 to primarily urge the control lever toward an elevated position therefrom, and to secondarily act upon the control lever to urge it toward a downwardly rotated position therefrom. Thus, with no can present upon the operating structure, and with the control lever 65 in a centered operating position, a slight downward pressure upon the control lever will enable the over-center spring S3 to urge the control lever toward a downwardly extending position over the operating parts of the mechanism, including the cutter block, blade, and drive wheel. A cover plate 88 is mounted upon the control lever 65, to thus provide an attractive and effective enclosure for the operating parts of the mechanism when the device is not in use.

The outermost end of the control lever 65 also supports a permanent magnet upon a short length of chain 86. The magnet 85 engages with the end wall of a can to be opened upon loading of the device, thus restraining the L-shaped control lever in its centered operating position and against primary movement thereof toward an elevated position by the over-center spring 83. However, as soon as the end wall of the can has been severed during the opening operation, the strength of the over-center spring 83 is suticient to lift the magnet 85 and its supported can end wall relative to the can just opened, to a slightly elevated position, thus moving the dwell surface 77 of t-he plate 76 out of engagement with the projection 78 of the movable contact arm 80, to deenergize the motor 46 and complete the opening operation.

An L-shaped spring plate secured to the cutter block 19, serves as a yieldable clamp means for accommodating cans having different rim thicknesses and diierent shapes. This spring plate 9i) is yieldable to accommodate the insertion of cans with different rim widths into the can opener, without jamming of the machine parts. It will be also noted that the face wall of the unit 10 is inclined downwardly and inwardly with respect to the base 12, thus maintaining the bottom of the can being opened in spaced relationship with the exterior surface finish of the enclosure sheath 15. Also, this allows for the provision of a guide block 91 which will maintain the can in a vertical position at all times, to maintain the end wall being severed at the proper cutting angle relative to the cutter blade 54.

In actual use, the control lever 65 and supported cover plate 88 is normally maintained in the downwardly extended position in closing engagement with the operating parts of the machine so as to provide a neat and attractive appearance. When it is desired to use the can opener, the L-shaped control lever 65 is manually rotated to its uppermost position as shown in FIG. 4, in which position such is held by the engagement of the edge 71 of the mounting lever 33 within the indent 73 of the control lever tail piece. In this position of the control lever 65, the drive wheel 53 is also arcuately removed from the cutter yblade 54, thus facilitating the insertion of the rim 93 of the can 94 into the lspace between the cutter blade 54 and the drive wheel 53. In this position of the control lever 65, the dwell surface 77 is also removed from the projection "I8 of the switch contact arm 86, thus preventing energization of the motor 46. As. soon as the can has been positioned, the lever 65 is moved downwardly toward the end wall of the can to lbe severed, so that the magnet S5 contacts the end wall of the can and retains the lever 65 in its centered operating position shown in FIG. 2, in which position, the dwell surface 77 engages the projection 73 of the movable contact 80, to energize the motor 46. Energization of the motor 46 supplies driving power to the drive wheel 53 through the aforementioned gear train and clutch mechanism, thus causing the hardened teeth of the drive wheel to elevate and rotate the can with respect to the blade 54, so that the can is pierced and the cutting action started and continued by the operation of the motor 46. The motor 46 remains energized so long as the parts remain in the operating position shown in FIG. 2. However, as soon as the end wall of the can has been completely severed, the magnet 3S will elevate it in response to the action of the over-center spring 83, thus causing the dwell surface 77 to move out of engagement with the projection '78, to deenergize the motor 46. The lever 65 is then manually elevated to the fully raised position shown in FlG. 4, to disengage the drive wheel 53 from the bead 93 of the can 94 to provide for the removal ot the can. The cover plate and control lever 65 may then be returned to the completely at-rest position, enclosing the operating parts from view and providing the initial storage position.

In the event that the cutter wheel becomes jammed with a can being opened during the operation of the device, driving motion of the motor will continue to be transmitted to the spur gear 4S. However, since the drive shaft 36 is locked against rotation by the jamming action of the cutter wheel with the can being opened, the torsion spring 49 will yield suiliciently to prevent damage to the parts.

Horizontal variations in metal thickness and seam thickness of the rim for diierent sizes and types of cans are compensated for by a spring type washer 95 mounted upon the drive shaft 30 and acting upon the drive wheel 53 and bushing 96 which accommodate the arcuate movement of the shaft within the slot 57. Thus, through the cooperating action of the L-shaped spring plate 96 and spring washer 9S, a can opener is provided with a limited amount of power, but which is capable of handling the various shapes and sizes of cans without jamming or overloading. These features also overcome dierences encountered in the size and shape of the can rim in the event that the can rim has been damaged or distorted during handling. ln the event of jamming for any reason whatsoever, in a manner hereinbefore described, the torsion spring 49 will tend to reverse the driving mechanism in response to deenergization of the motor 46, thus automatically helping to release the can from its jammed position. Also, while the initial yielding of the spring 49 will absorb the extraordinary initial loading of the mechanism which would otherwise result, it may also disengage the driving tab 5l in the event that the motor remains energized during the initial jamming of the parts and the gear 48 has rotated sufficiently to cause the release of the terminal of the spring 49 from the driving tab Si.

While this invention has been described with particular reference to the construction shown in the drawing, it is to be understood that such is not to be construed as imparting limitations upon the invention, which is best defined by the claims appended hereto.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

l. A motor operated can opener comprising, in combination, a main frame, a cutter block having a piercing cutting blade mounted upon said main frame, a can rim engaging drive wheel supported upon said main frame for arcuate movement relative to said cutter blade between a retracted and an engaged position, engaging spring means yieldably urging said drive wheel toward said engaged position with said cutter blade to etfect driving contact with the rim of a can to pierce an end wall of the can and to eiiect rotation of the can relative to said cutter blade, an electric motor carried by said main trame having means for connection to a source of electrical energy, a pressure responsive switch in circuit with said motor and source controlling energization with said motor, transmission means drivingly connecting said drive wheel to said motor, and manually operated control lever means carried by said frame in an initial position having portions restraining said drive wheel in a retracted position away from said cutter blade against the action of said spring means, and said control lever means having a portion movable relative to said switch upon release of said drive wheel for movement toward said blade to energize said motor.

2. A motor operated can opener as set forth in claim l, wherein said control lever means comprises an L-shaped member pivotally carried upon said main frame, one end of said member being arcuately movable relative to said blade and drive wheel.

3. A motor operated .can opener as set forth in claim 2, further comprising a closure carried by said lever member movable into an enclosing position with said blade and drive wheel in response to movement of said lever to a storage position.

4. A motor operated can opener as set forth in claim 1, comprising a magnet carried by said opposite end of said lever member, said magnet being attracted to a can upon movement of said drive wheel toward said blade, overcenter spring means acting between said main frame and said lever member ryieldably urging said lever member in opposite directions from a central position primarily toward said initial position and secondarily toward said storage position, ysaid lever member in said central position actuating said switch to energize said motor, and magnetic attraction between said magnet and a can Wall maintaining said lever member in said central position, whereby upon severance of the can wall from a can being opened, said control lever member is movable toward said initial position with a can iwall to deenergize said motor.

5. A motor operated can opener as set forth in claim l, further comprising overload clutch means acting between said drive shaft and said gear means accommodating continued rotation of said drive shaft in response to jamming of said drive wheel.

6. A motor operated can opener as set .forth in claim 5, wherein said one end of said control member is pivotally -supported upon said main frame for pivotal movement about an axis extending transversely of the axis of rotation of said mounting lever, and cam means acting between said control lever and said mounting lever for controlling the arcuate movement of said drive shaft relative to said blade in response to mov-ement of said control lever member.

7. A motor operated can opener as set forth in claim 6, wherein said cam means comprises one edge of said mounting lever, and a projection carried by said control lever having an arcuate slide surface slidably engaged with said one edge of said mounting lever.

8. A motor operated can opener as set forth in claim 7, further comprising an indent at one extremity of said arcuate slide surface of Said projection .receiving said edge of said mounting lever in said initial position of said control lever member releasably securing said control lever member and said mounting lever in said initial position with said drive shaft spaced from said blade against the action of said respective over-center and engaging spring means.

9. A motor operated can opener as set forth in claim 8, further comprising yieldable clamp means mounting the can being opened in supported engagement with said blade and said drive wheel in said engaged position with said drive wheel, said clamp means comprising a yieldable spring element extending from said cutter blade toward said drive wheel, and said clamp means yieldably accommodating can wall thicknesses of different dimensions.

l0. A motor operated can opener as set forth in claim 9, further comprising a spring washer slidably mounted upon said drive shaft between said drive wheel and said mounting lever, said spring washer yieldably accommodating limited longitudinal movement of said drive shaft relative to said blade. to accommodate cans having walls of different thicknesses.

ll. In an electric can opener having a main frame for supporting a motor and operating parts thereupon, a

8 substantially rigid sheath enclosing the sides and front References Cied in the le of this patent of Asaid main frame, a skeletal framework carried by Said r sheath, a mounting plate enclosing the rear side of said UNITED STATS PAFENTS main frame, and fasteners detachably securing said mount- 2,896,319 Finette July 28, 1957 ing plate directly to said main frame and sheath, whereby 5 2,952,073 Congdon Sept. 13, 1960 stresses set up by the operating parts of the can opener 2,968,094 Sachs Jam 177 1951 ,are insulated from ysaid skeletal framework.

Images