Electrically Powered Can Opener

Abstract

An electrically powered can opener including a base mounted detachably on the upright front member of the can opener housing, a cutter base carrying rotatably a rotary cutter and having a pivotal shaft, said pivotal shaft being extending through said base and supported by said upright front member for rotation and ready removal, said base and cutter base being unified by said pivotal shaft, a feed wheel holder fitted rotatably withing a loose aperture formed in said base, a driving shaft disposed in said housing for axially separable connection with said feed wheel holder through said front member and a latching member provided in said housing for precluding separation of said base from said housing and for permitting operation from the exterior of said housing.

Description

BACKGROUND OF THE INVENTION

It is conventional practice in opening a can with use of an electrically powered can opener to insert the end rim of the can between a toothed feed wheel extending rotatably in front of the upright front member of the can opener housing and a rotary cutter carried by a cutter base pivotally supported on the housing above the feed wheel and to cut progressively the lid of the can near the inside surface of the end rim. Mainly for the purpose of cleaning the cutter after a can opening operation, the electrically powered can opener of this type is constructed in a manner that the cutter together with the cutter base can be separated from the housing. However, in the course of repeated usages of the can opener, it happens that not only the cutter but also the toothed feed wheel generally affixed to the end extremity of the driving shaft extenting from the interior to the exterior of the housing is necessary to be washed. It is a very troublesome work to wash the toothed feed wheel mounted on the housing, because the cutter is of a very small size in comparison with the housing. It is, of course, possible to construct the toothed feed wheel and the driving shaft as a unitary block readily separable from the housing for convenience for cleaning. With this construction, however, the lubricating oil attached on the driving shaft escapes into washing solution in a reservoir and contaminates the reservoir and the toothed feed wheel. This contamination is undesirable in the light of a device dealing with cans containing food stuffs. The lubricating oil attached on the driving shaft is decreased in every washing work and there is such trouble that lubricating oil must be supplemented.

SUMMARY OF THE INVENTION

An electrically powered can opener according to the present invention includes a base detachably mounted on the upright front member, a cutter base carrying a cutter rotatably and having a pivotal shaft, said pivotal shaft being supported rotatably and separably through an apertured portion of said base and said base and cutter base being unified by said pivotal shaft, and a latching member operable from the exterior of the housing for the purpose of precluding withdrawal of said base. A feed wheel holder carrying a rotary cutter fixedly is supported on said base for fee rotation and is connected for axial separation to the end extremity of a driving shaft extenting beyond the upright front member of the housing from the interior of same. When the pivotal shaft is supported by the upright front member and is latched by the latching member not to be withdrawn, the feed wheel holder is in position to be connected to and rotated by the driving shaft. When the pivotal shaft is made separable by operating the latching member, the cutter base carrying the rotary cutter and the base carrying the feed wheel holder can be withrawn as a unified body from the housing for the purpose of washing. Thus, cleaning work becomes very easy and the contamination of the cutter or the toothed feed wheel with lubricating oil of the driving shaft is eliminated.

IN THE DRAWINGS

FIG. 1 is a front elevational view of an electrically powered can opener;

FIG. 2 is a sectional side elevational view of the electrically powered can opener;

FIG. 3 is a rear view of the electrically powered can opener with the rear member of the housing being taken away;

FIG. 4 is a perspective view in partial cross-section showing the mounting relationship of a cutter base and a base with respect to the housing;

FIG. 5 is a rear view of the cutter base and the base;

FIG. 6 is a section along line 6--6 in FIG. 3;

FIG. 7 is a side elevational view of the base separated from the housing;

FIG. 8 is an exploded perspective view showing the relationship between the housing, the base and the cutter base of the can opener; and

FIGS. 9a-9c are fragmental perspective views showing the connecting relationship between a toothed feed wheel and the driving shaft thereof.

Referring to the drawings, a housing of a can opener is indicated by numeral 10 and is provided with an upright front member 10'. The upright front member 10' is so shaped to have a square depressed portion 11, from the internal surface of which a horizontal bearing boss 12 is protruding towards the interior of the housing. On the left of and above the bearing boss 12, another bearing boss 13 is similarly extending towards the interior of the housing from the internal surface of the depressed portion 11 and under the bearing boss 12, a can guide 14 is extending forwardly of the housing 10 from the upright front member 10'. A cutter base 15 having an integral grip 15' at one end extremity and a pivotal hole 15" at the other end portion is mounted rotatably on the upright front member 10' by a pivotal shaft 16 inserted in the pivotal hole 15" and the bearing boss 13 and to the end portion of the pivotal shaft a nut 17 is in threaded connection with pivotal shaft 16 for unification of the pivotal shaft and the cutter base and for precluding withdrawal of the former. The intermediate portion of the pivotal shaft 16 is provided with a head 18 and between this head and the nut 17, another nut 19 is in connection with pivotal shaft 16 as a spacer. From the lower part of the cutter base 15, a cutter carrying stud 20 is extending in an oblique downward direction and a rotary circular cutter 21 is mounted rotatably on the stud 20, withdrawal of the cutter being prevented by a screw 22 affixed to the end extremity of the stud 20. As a means for holding a cut-off can lid, a magnet 23 is held forwardly of the cutter 21 by an arm 24 extending from the upper portion of the cutter base 15. A base 25, which has such a size that it can be positioned on the front surface of the depressed portion 11, is provided with a pair of perpendicular stopping members 26 at both sides of the base. The end portions of these stopping members are made thin as shown and the lower edges of the same have cuts 26' and 26' respectively. Through the upper portion of the base 25, a loose aperture 27 is bored and the part of the pivotal shaft 16 between head 18 and nut 19 is inserted rotatably within this loose aperture 27. The stopping members 26 are inserted in the interior of the housing through slots 25' formed through the depressed portion 11 of the upright front member 10'. A push out spring 28 is secured on the front surface of the depressed portion 11 whereby the base 25 placed closely before the front surface of the depressed portion 11 is biased forwardly of the housing by the push out spring 28.

Now, a can driving mechanism is described. In another aperture 29 bored through the base 25, a feed wheel holder 31 carrying a toothed feed wheel 30 is inserted for free rotation and the end extremity of the feed wheel holder facing the front surface of the depressed portion 11 is provided with a diametrical jointing groove 32. Along the axis of the feed wheel holder 31, an axial hole 33 is bored for the purpose of faciliating centering between the feed wheel holder and a driving means thereof. The feed wheel holder is made considerably thin as compared with the diameter of the aperture 29 and the base 25 is not subjected to a reaction force of the cutting operation even when the toothed feed wheel 30 is driven. Numeral 34 indicates a circular groove formed on the cylindrical surface of the toothed feed wheel and a C-shaped ring 35 of an external diameter larger than the diameter of the aperture 29 is mounted in said groove in order to preclude withdrawal of the feed wheel holder. With the base 25 and the cutter base both mounted on the upright front member 10', the lowermost edge of the cutter 21 is placed closely in front of the uppermost edge of the toothed feed wheel 30. The driving shaft 36 for the toothed feed wheel 30 is inserted rotatably in the bearing boss 12 and a cylindrical centering member 37 integral and coaxial with the driving shaft 36 is provided at the end extremity of same near the front surface of the depressed portion 11. This centering member takes on such a form that it fits exactly in the axial hole 33 but can slide axially therein. On the necked down portion between the centering member 37 and the driving shaft 36, an integral projection 38 having a form suitable for being fit in the jointing groove 32 is provided. Thus, the centering of the feed wheel holder 31 is maintained as the result of insertion of the centering member 37 in the axial hole 33 and the weight loading the axial hole 33 is born by the centering member 37 but does not exert on the base 25 as the result of the support of the feed wheel holder by the centering member 37. Consequently any provision of lubricating oil is not necessary between the holder 31 and the base 25. The engagement between the projection 38 and the jointing groove 32 permits the transfer of torque from the driving shaft 36 to the feed wheel holder 31. On the other end portion of the driving shaft 36 extending beyond the end extremity of the bearing boss 12, a gear 39 is fastened by means of a nut 40 and a planar spring 41 is secured on the housing 10 for the purpose of urging the end extremity 36' of the driving shaft 36 further extending the gear 39 towards the upright front member 10'. An electric motor 42 is mounted fixedly in the housing 10 and is connected to the gear 39 through a reduction gear assembly 43. Next, as illustrated in FIG. 3 and 6, a guiding member 44 of a L-shaped section is secured on the internal surface of the upright front member 10' under the bearing boss 13 and a pair of guiding apertures 44' and 44' are bored through the horizontal portion of the guiding member 44. A latching member 45 has, at its lower portion, a pair of legs 46 and 46 of a form suitable for being inserted slidably in the guiding aperture and, at its upper portion, an elongate hole 47. The legs 46 and 46 are inserted in the guiding aperture 44' and 44' and positioned near the internal surface of the upright front member 10' by means of a screw 48 screwed into the upright front member 10' whereby the vertical position of the latching member 45 is adjustable within the length of the elongate hole 47. A compression spring 50 placed between a spring mount 49 and the bearing boss 13 biases the latching member 45 upwardly. The latching member 45 is provided with a pair of rectangular openings 51 and 51 where the stopping members 26 and 26 are inserted and the cuts 26' and 26' receive the lower edges of the openings 51 and 51. A push button 52 is attached fixedly on the top of the latching member 45 and extends ordinarily through the top member of the housing 10 upwardly. A start push button 53 is extending upwardly of the top member of the housing at a position where the push button 53 can be depressed by the grip 15' of the cutter base 15 and electrical contacts 55 and 55' connected in the power source circuit of the electric motor 42 are operated by a operation rod 54 connected to the push button 53. The above-mentioned pivotal shaft 16 connected to the cutter base 15 has only to function to provide pivotal support of the cutter base 15 against the base 25 and so, as the case may be, the pivotal shaft 16 can be shortened to present no portion extending in the bearinged boss 13. As a latching member to latch the base 25 and stopping members secured on the base and engageable with this latching member, members indicated by numerals 26 and 45 respectively in FIG. 6 were illustrated but these members have only to provide detachable mounting of the base 45 on the upright front member 10'.

As is clearly seen from FIGS. 4 and 8, the base 25 and the cutter base 15 are connected for free rotation of the latter by means of the pivotal shaft 16, the head 18 and nuts 17 and 19 but the cutter base 15 and the base 25 may be constructed separately in an arbitrary manner such as to omit the head 18. However, as are separately constructed, these can be mounted together on the housing for ready dismounting. Thus, with this construction, it becomes possible to take off only the cutter base leaving the base 25 mounted and to withdraw the cutter base 15 firstly and then base 25 if desired.

Next, the treatment of the above-mentioned construction is discribed. As shown in FIG. 7, when the cutter base 15 and the base 25 unified by the pivotal shaft 16 are mounted on the housing 10, the pivotal shaft 16 is inserted in the bearing boss 13, the stopping members 26 and 26 are inserted in the slots 25' and 25' respectively and then the base 15 is pushed towards the upright front member when the thin end portion of the member 26 begins to enter the opening 51, said end portion lowers the latching member 45 against the spring 50. At the same time, the centering member 37 for the driving shaft 36 begins to enter the axial hole 33 of the feed wheel holder 31. In the course of these operations, the cuts 26' come in registration with the lower edges of the openings 51 and the latching member 45 is returned by a length equal to the depth of the cut 26'. Thus, the base 25 and the cutter base 15 are mounted on the housing 10. When the jointing groove 32 of the feed wheel holder 31 coincides with the projection 38 of the driving shaft 36 by chance, the fit situation as shown in FIG. 9c results. However, the jointing groove 32 does not coincide with the projection 38 but contacts with the same in a crossing position in general as shown in FIG. 9b. The increase in the axial distance due to the misfitting between the jointing groove 32 and the projection 38 is adjusted by the axial displacement of the driving shaft 36 against the planar spring 41, and the driving shaft 36 is biased by the planar spring 41. When, with the cutter base 15 and base 25 thus mounted, the lower portion of the end rim of a can to be opened is made in contact with the toothed feed wheel 30 and the grip 15' of the cutter base 15 is gasped to be lowered, the start push button 53 is depressed by the grip 15' to close the electrical contacts 55 and 55' and the electric motor 42 is started to rotate the driving shaft 36 through the reduction gear assembly 43. The toothed feed wheel is rotated with support by the driving shaft 36 immediately when the projection 38 is fit in the jointing groove 32 and after only the driving shaft 36 rotates to fit the projection 38 in the jointing groove 32 due to the biasing force of the planar spring when the projection 38 is not fit in the jointing groove 32. At this time, as the edge of the rotary cutter 21 is in contact with the can lid closely inside the end rim and the can is rotated by the toothed feed wheel 30, also the rotary cutter 21 is rotated with the stud 20 as the center axis and the driving force of the toothed feed wheel 30 exerting on the rotary cutter 21 through the can lid rotates the cutter base 15, as a torque, in a direction towards the can around the pivotal shaft 16, the piercing position of the rotary cutter 21 into the can lid being maintained automatically. In this situation, the rotary cutter 21 proceeds to open the can. When the can is cut out completely, the above-mentioned torque disappear and the grip 15' is lifted slightly by a restoring spring suitably provided. Then the electrical contacts 55 and 55' are disconnected to stop the electric motor 42. The opened can can be withdrawn from the can opener by further lifting the grip 15'.

Next, when it is desired to withdraw the rotary cutter 21 and the toothed feed wheel 30 from the housing for the purpose of cleaning, the engaging relationship between the latching member 45 and the stopping members 26 is released by depressing the push button 52 to lower the latching member 45 once and then making the cuts 26' out of registration with the lower edge of the opening 51. Because no members prevent the cutter base 15 and the base 25 unified by the pivotal shaft 16 from moving forwardly of the housing 10, the base 25 and the cutter base 15 are pushed forth slightly by the force of the push out spring 28 (the planar spring 41 in the absence of the push out spring 28) urging the base forwardly and keep their slightly pushed out position. Then, the cutter base 15 carrying the rotary cutter and the base 25 carrying the toothed feed wheel are withdrawn from the housing 10, the situation shown in FIG. 7 being attained.

As is understood from the foregoing description description, the toothed feed wheel 30 is separated from the housing 10 very readily and quickly by releasing the engagement between the stopping members 26 and the latching member 45 and cleaning work of the toothed feed wheel becomes very easy. Of course, contamination of the toothed feed wheel 30 with lubricating oil of the driving shaft 36 escaping in washing solution at the time of washing is avoided, because the toothed feed wheel 30 is separated from the driving shaft therefor and the periphery of the aperture 29 can practically dispense with the provision of lubricating oil. Besides, provision of lubricating oil for the driving shaft 36 is not necessary as the lubricating oil on the driving shaft 36 is not washed off.

Although the present invention has been described with preferred embodiments, it should be understood that many modifications and changes are possible without departing from the spirit of the present invention and the accompanying claims.

Claims

What I claim is:

1. In an electrically powered can opener having a housing, a driving shaft rotatably supported in said housing and an electric motor for rotating said driving shaft, a combination therewith of an upright front member of said housing, a cutter base having a grip at one end portion, a rotary cutter rotatably carried by said cutter base, a base closely mounted on said upright front member and provided with two loose apertures, a pivotal shaft affixed to said cutter base, said pivotal shaft extending through one of said loose apertures, said base being disposed on said upright front member, means unifying said cutter base and said base in cooperation with said pivotal shaft, a feed wheel holder extending through and spaced from the other of said loose apertures, a toothed feed wheel carried by said feed wheel holder, stopping member perpendicularly secured on said base, said feed wheel holder being inserted in the other of said loose apertures so that the base may not be subjected to the reaction force of the can cutting operation, said stopping member extending interiorly of said housing through a slot formed through said upright front member, said feed wheel holder and said driving shaft being connected to establish the transmission of rotation from the latter to the former and to make possible mutual separation in the axial direction, means precluding withdrawal of said feed wheel holder from said base, a latching member operable from the exterior of said housing and moveable vertically, said latching member having such a form that at a certain position thereof it cooperates with said stopping members to preclude separation of said base from said upright front member and a spring for biasing said latching member to a position where said latching member engages with said stopping members with the engagement between said latching member and said stopping member being released by depressing said latching member against said spring.

2. The combination as described in claim 1 including an axial hole bored along the axis of said feed wheel holder, a diametrical jointing groove formed on the end extremity surface of said feed wheel holder facing said driving shaft, an integral centering member formed on the end portion of said driving shaft facing said feed wheel holder, a projection formed on the necked down portion between said driving shaft and said centering member, said centering member having a form fit exactly in said axial hole, said projection having a form fit exactly in said diametrical groove, and a spring secured on said housing for biasing said driving shaft towards said upright front member.

3. An electrically powered can opener as described in claim 1 including a spring secured on said upright front member, said spring biasing said base away from said upright front member.

4. The combination as described in claim 1, including electrical contacts connected in the power source circuit of said electrical motor, an operation rod for operating said contacts and a start push button attached to said operation rod, said start push button extending exteriorly of the top of said housing at a position where said start push button can be depressed by said grip of said cutter base.

5. The combination as described in claim 1, including an arm extending from said cutter base forwardly of said rotary cutter and a magnet supported by said arm for the purpose of attracting a cut off can lid.